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  • Articles  (82,223)
  • American Association for the Advancement of Science  (71,603)
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  • 1
    Publication Date: 2019-04-18
    Description: Entanglement is a key feature of many-body quantum systems. Measuring the entropy of different partitions of a quantum system provides a way to probe its entanglement structure. Here, we present and experimentally demonstrate a protocol for measuring the second-order Rényi entropy based on statistical correlations between randomized measurements. Our experiments, carried out with a trapped-ion quantum simulator with partition sizes of up to 10 qubits, prove the overall coherent character of the system dynamics and reveal the growth of entanglement between its parts, in both the absence and presence of disorder. Our protocol represents a universal tool for probing and characterizing engineered quantum systems in the laboratory, which is applicable to arbitrary quantum states of up to several tens of qubits.
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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  • 2
    Publication Date: 2019-10-19
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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  • 3
    Publication Date: 2019-04-03
    Description: Study of spatiotemporal dynamics of temperature is vital to assess changes in climate, especially in the Himalayan region where livelihoods of billions of people living downstream depends on water coming from the melting of snow and glacier. To this end, temperature trend analysis is carried out in Narayani river basin, a major river basin of Nepal characterized by three climatic regions: tropical, subtropical and alpine. Temperature data from six stations located within the basin are analyzed. The elevation of these stations ranges from 460 to 3800 m asl. and the time period of available temperature data ranges from 1960–2015. Multiple regression and empirical mode decomposition (EMD) methods are applied to fill in the missing data. Annual as well as seasonal trends are analyzed and Mann-Kendall test is employed for testing the statistical significance of detected trend. Results indicate significant cooling trends before 1970s, and warming trends after 1970s in the majority of the stations. The warming trends range from 0.028 ∘ C per year to 0.035 ∘ C per year with a mean increasing trend of 0.03 ∘ C per year after 1971. Seasonal trends show highest warming trends in monsoon season followed by winter, pre-monsoon, and post-monsoon season. However, difference in warming rates between different seasons isn’t sufficiently large. An average temperature lapse rate of −0.006 ∘ C per m with the steepest value (−0.0064 ∘ C per m) in pre-monsoon season and least negative (−0.0052 ∘ C per m) in winter season is observed for this basin. A comparative analysis of the gap-filled data with freely available global climate data sets shows reasonable correlation thus confirming the suitability of the gap filling methods.
    Electronic ISSN: 2413-4155
    Topics: Natural Sciences in General
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  • 4
    Publication Date: 2019-04-15
    Description: A portable Fourier Transform Spectrometer (B3M-IR) is built and used to measure atmospheric trace gases in the city of Beijing during Olympic Games in 2008. A short description of the instrument is first provided in this paper. A detailed spectral analysis is then presented. The total columns of ozone (O3), carbon monoxide (CO), methane (CH4) and nitrous oxide (N2O) are retrieved from the ground-based solar absorption spectra recorded by the B3M-IR during the Olympic Games. Lacking validation data, only the retrieved total column of O3 is compared with that retrieved by MAX-DOAS, which is deployed at the same station. The mean difference between the two methods of measurement is 6.5%, demonstrating the performance and reliability of B3M-IR.
    Electronic ISSN: 2413-4155
    Topics: Natural Sciences in General
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  • 5
    Publication Date: 2019-11-01
    Description: As there is lack of understanding about the effect of transitioning between different flooring materials on the gait of older adults, this study investigated the effect of transitioning between a carpeted floor and a vinyl floor on the gait characteristics of older adults. Fourteen older (65 years old and over) and 14 younger (18 to 35 years old) adults walked on different transitional floors by measuring various gait parameters. While the older participants had greater toe clearance than their younger counterparts, the older participants had smaller toe clearance on a carpeted floor than on a vinyl floor, which would increase the probability of a trip-induced fall. Further, the study found the slower transitional acceleration of the whole body COM and the increased friction demand, especially during the toe-off phase, rather than heel contact phase, which will lead to a slip-induced fall on a vinyl floor shortly after transitioning from a carpeted floor to a vinyl floor. Although the increased likelihood of a slip or trip accident was found throughout the changes in gait parameters, the older participants did not perceive of slipping and tripping much. Therefore, older adults are recommended to be made aware of the danger of slipping and tripping while transitioning between different flooring materials.
    Electronic ISSN: 2413-4155
    Topics: Natural Sciences in General
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  • 6
    Publication Date: 2019-03-20
    Description: One of the important features of polymethine (cyanine) dyes is isomerization about one of C–C bonds of the polymethine chain. In this review, spectral properties of the isomers, photoisomer-ization and thermal back isomerization of carbocyanine dyes, mostly meso-substituted carbocy-anine dyes, are considered. meso-Alkyl-substituted thiacarbocyanine dyes are present in polar solvents mainly as cis isomers and, hence, exhibit no photoisomerization, whereas in nonpolar solvents, in which the dyes are in the trans form, photoisomerization takes place. In contrast, the meso-substituted dyes 3,3′-dimethyl-9-phenylthiacarbocyanine and 3,3′-diethyl-9-(2-hydroxy-4-methoxyphenyl)thiacarbocyanine occur as trans isomers and exhibit photoisomerization in both polar and nonpolar solvents. The behavior of these dyes may be ex-plained by the fact that the phenyl ring of the substituent in their molecules can be twisted at some angle, removing the substituent from the plane of the molecule and reducing its steric ef-fect on the conformation of the trans isomer. In some cases, photoisomerization of cis isomers of meso-substituted carbocyanine dyes is also observed (for some meso-alkyl-substituted dyes com-plexed with DNA and chondroitin-4-sulfate; for 3,3′-diethyl-9-methoxythiacarbocyanine in moderate polarity solvents). The cycle photoisomerization–thermal back isomerization of cya-nine dyes can be used in various systems of information storage and deserves further investiga-tion using modern research methods.
    Electronic ISSN: 2413-4155
    Topics: Natural Sciences in General
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  • 7
    Publication Date: 2019-07-01
    Description: Nucleolin is an RNA binding protein that is involved in many post-transcriptional regulation steps of messenger RNAs in addition to its nucleolar role in ribosomal RNA transcription and assembly in pre-ribosomes. Acetylated nucleolin was found to be associated with nuclear speckles and to co-localize with the splicing factor SC35. Previous nuclear pull down of nucleolin identified several splicing components and factors involved in RNA polymerase II transcription associated with nucleolin. In this report, we show that these splicing components are specifics of the pre-catalytic A and B spliceosomes, while proteins recruited in the Bact, C and P complexes are absent from the nucleolin interacting proteins. Furthermore, we show that acetylated nucleolin co-localized with P-SF3B1, a marker of co-transcriptional active spliceosomes. P-SF3B1 complexes can be pulled down with nucleolin specific antibodies. Interestingly, the alternative splicing of Fibronectin at the IIICS and EDB sites was affected by nucleolin depletion. These data are consistent with a model where nucleolin could be a factor bridging RNA polymerase II transcription and assembly of pre-catalytic spliceosome similarly to its function in the co-transcriptional maturation of pre-rRNA.
    Electronic ISSN: 2413-4155
    Topics: Natural Sciences in General
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  • 8
    Publication Date: 2019-05-27
    Description: In our earlier work, we showed that a low-energy state of an electron beam exists in a nonuniform channel between two virtual cathodes in a magnetron with diffraction output, which consists of three uniform sections with increasing radius. A uniform axial magnetic field fills the interaction space. This led to magnetron operation with 〉90% efficiency when combined with a magnetic mirror field at the output end. In this present paper, we show that a low-energy state of an electron beam can be realized in a uniform channel in which an increasing magnetic field is used in order to create a magnetic mirror at the output end. We consider two cases, one where the injected beam current slightly exceeds the space-charge-limiting current and the other where the injected beam current greatly exceeds the space-charge-limiting current. On the time scale of relevance to planned experiments (∼30 ns), when the injected current slightly exceeds the space-charge-limiting current a stationary virtual cathode forms and when the injected current greatly exceeds the space-charge-limiting current the virtual cathode oscillates back and forth.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 9
    Publication Date: 2019-05-13
    Description: We explored the effect of magnetic field strength | B | and geometry (degree of balancing) on the deposition rate and ionized flux fraction F flux in dc magnetron sputtering (dcMS) and high power impulse magnetron sputtering (HiPIMS) when depositing titanium. The HiPIMS discharge was run in two different operating modes. The first one we refer to as “fixed voltage mode” where the cathode voltage was kept fixed at 625 V while the pulse repetition frequency was varied to achieve the desired time average power (300 W). The second mode we refer to as “fixed peak current mode” and was carried out by adjusting the cathode voltage to maintain a fixed peak discharge current and by varying the frequency to achieve the same average power. Our results show that the dcMS deposition rate was weakly sensitive to variations in the magnetic field while the deposition rate during HiPIMS operated in fixed voltage mode changed from 30% to 90% of the dcMS deposition rate as | B | decreased. In contrast, when operating the HiPIMS discharge in fixed peak current mode, the deposition rate increased only slightly with decreasing | B | . In fixed voltage mode, for weaker | B | , the higher was the deposition rate, the lower was the F flux . In the fixed peak current mode, both deposition rate and F flux increased with decreasing | B | . Deposition rate uniformity measurements illustrated that the dcMS deposition uniformity was rather insensitive to changes in | B | while both HiPIMS operating modes were highly sensitive. The HiPIMS deposition rate uniformity could be 10% lower or up to 10% higher than the dcMS deposition rate uniformity depending on | B | and in particular the magnetic field topology. We related the measured quantities, the deposition rate and ionized flux fraction, to the ionization probability α t and the back attraction probability of the sputtered species β t . We showed that the fraction of the ions of the sputtered material that escape back attraction increased by 30% when | B | was reduced during operation in fixed peak current mode while the ionization probability of the sputtered species increased with increasing | B | , due to increased discharge current, when operating in fixed voltage mode.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 10
    Publication Date: 2019-10-14
    Description: In this paper the generation and diagnostics of a reduced pressure (300 mTorr to 3 Torr) plasma generated inside an electrodeless containment vessel/chamber are presented. The plasma is ignited by a guided ionization wave emitted by a low temperature pulsed plasma jet. The diagnostics techniques include Intensified Charge Coupled Device (ICCD) imaging, emission spectroscopy, and Langmuir probe. The reduced-pressure discharge parameters measured are the magnitude of the electric field, the plasma electron number density and temperature, and discharge expansion speed.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 11
    Publication Date: 2019-07-05
    Description: Plasma-driven advanced oxidation represents a potential technology to safely re-use waters polluted with recalcitrant contaminants by mineralizing organics via reactions with hydroxyl radicals, thus relieving freshwater stress. The process results in some residual hydrogen peroxide, which can interfere with the standard method for assessing contaminant removal. In this work, methylene blue is used as a model contaminant to present a case in which this interference can impact the measured chemical oxygen demand of samples. Next, the magnitude of this interference is investigated by dosing de-ionized water with hydrogen peroxide via dielectric barrier discharge plasma jet and by solution. The chemical oxygen demand increases with increasing concentration of residual hydrogen peroxide. The interference factor should be considered when assessing the effectiveness of plasma to treat various wastewaters.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 12
    Publication Date: 2019-12-31
    Description: In this paper, an efficient inductively coupled medium pressure source for ultraviolet radiation (UV-source) is demonstrated. The lamp was operated with powers up to 3 kW while the radiation and the coldest point temperature were measured. In addition, different coil geometries were investigated. Here a symmetrical and asymmetrical winding density were compared. Also the operation pressures and DC to radiation efficiencies are presented. In this work, an operation pressure of one atmosphere and an UV-efficiency (200–380 nm) of 15.5% was achieved. This is comparable to conventional medium pressure Hg-lamp technology. The main advantage of the presented inductive lamp is the electrodeless operation and therefore the longer service life, since an electrode failure is eliminated.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 13
    Publication Date: 2019-05-04
    Description: We report on the electrical and optical characterization of the Plasma Coagulation Controller (PCC) device, a low temperature atmospheric plasma source for biomedical applications. This device, designed for the study of plasma-induced blood coagulation, has been developed to operate flexibly in several operational conditions, since it is possible to vary the applied voltage V p and the pulse repetition rate f in a quite wide range ( V p range: 2–12 kV, f range: 1–40 kHz). Emission spectroscopy measurements were conducted by varying the line of sight along the axis of helium and neon plasma plumes. The increase of the Reactive Oxygen and Nitrogen Species (RONS) has been observed, as one moves from inside the gas pipe to the outside, as a consequence of the gas mixture with the surrounding air. Furthermore, high-speed photographs of the plasma jet were taken, showing that the plasma is not uniformly distributed in a continuous volumetric region, the plasma being concentrated in localized structures called Pulsed Atmospheric-pressure Plasma Streams (PAPS). The propagation velocities of these objects have been examined, noting that they are not related to the propagation of ion sound waves. Rather, we provide indications that the streamer propagation speed is proportional to the electron drift velocity.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 14
    Publication Date: 2019-06-19
    Description: For the use of natural fibers in composite materials it is often necessary to improve the compatibility between fiber (sizing) and polymer matrix systems, e.g., by increasing the number of functional groups on the fiber surfaces. In this work, a dielectric barrier discharge (DBD) source in plane configuration is used to treat flax fabrics in ambient air. It is examined whether it is possible to increase the functionality on both fabric sides, which is achieved by simple changes in the DBD setup. After evaluating the treatment homogeneity of the filamentary plasma, an explanation for the treatment mechanism on the fiber surfaces is developed. It is shown that waxy substances, which naturally occur on natural fibers, play an important role in the wettability of the fabric.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 15
    Publication Date: 2019-07-04
    Description: A helium-based atmospheric pressure plasma jet (APPJ) with various flow rates of argon gas as a variable working gas was characterized by utilizing optical emission spectroscopy (OES) alongside the plasma jet. The spectroscopic characterization was performed through plasma exposure in direct and indirect interaction with and without de-ionized (DI) water. The electron density and electron temperature, which were estimated by Stark broadening of atomic hydrogen (486.1 nm) and the Boltzmann plot, were investigated as a function of the flow rate of argon gas. The spectra obtained by OES indicate that the hydroxyl concentrations reached a maximum value in the case of direct interaction with DI water as well as upstream of the plasma jet for all cases. The relative intensities of hydroxyl were optimized by changing the flow rate of argon gas.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 16
    Publication Date: 2019-07-08
    Description: In this work, micro-arc discharge is investigated using a needle-to-plane electrode system placed with a micro-gap in highly conductive artificial seawater. A major problem with microarc discharge is the erosion of electrodes caused by the high current of the arc; however, it was found that erosion of the needle electrode did not have any effect on the discharge process in the case of precise control of the discharge gap. A simple mathematical model was developed for a more detailed study of the preheating phase of the discharge. The modeling showed good agreement with the experimental results and confirmed that the needle electrode could be reused to generate reproducible micro-arc discharges even after the erosion caused by the arc. Moreover, it was found that, in certain conditions, the preheating phase could be simulated using a simple inductor-capacitor-resistor (LCR) oscillator model with a resistor instead of electrodes immersed in the liquid. It was confirmed that the shape of the needle electrode’s tip did not affect the measurement of optical emission spectra in the case of precise focusing, which could be used in the development of compact analytical tools for on-site analysis of deep-sea water using atomic emission spectroscopy.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 17
    Publication Date: 2019-05-03
    Description: This paper details the design, simulation, and optimization of a low-impedance high repetition rate magnetically insulated transmission line oscillator (MILO) driven by a compact Marx generator. The project goals require the MILO to generate an radio frequency (RF) pulse within the S-band frequency range with a peak output power greater than 1 GW with greater than 10% efficiency. Its design is based on a set of base equation which provide critical component dimensions applied to a three-dimensional model constructed within CST studio suite used in a particle-in-cell (PIC) simulation. Additional to the geometric model, simulation of the MILO with non-ideal material properties and a lumped element modeling of the Marx generator were performed. The results of these simulations then informed changes to the model as to the optimizing performance of the device. Within the framework of the model, the final MILO design achieves the design goals with an approximate RF peak power of 4.5 GW at 2.5 GHz operating in the TM 01 mode when an input driving pulse with a peak voltage of 600 kV while providing 58 kA is applied.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 18
    Publication Date: 2019-06-08
    Description: The paper considers the quasi-monochromatic radio frequency oscillations that are observable in transmission lines of doubly connected cross-sections, partially filled with a magnetized ferrite. The frequencies and amplitudes of the oscillations appearing under the impact of short carrier-free electric pulses are determined by dispersive and non-linear properties of the line’s structure. The dispersion characteristics are governed by the geometry and size of the line and the spatial arrangement in the line of the ferromagnetic material with its intrinsic dispersion. The dependences shown by the oscillation parameters in real physical experiments are reproduced and analyzed via numerical simulation within models which account separately for different physical properties of the material and the structure.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 19
    Publication Date: 2019-01-11
    Description: A new type of high-power electronic device—a gyroton with a corrugated resonator—is described and investigated. Spatial bunching of the electron beam does not occur in this device, however, highly efficient electron beam power conversion into the rotating electromagnetic field power is possible. The rectilinear electron beam deviates from the axis by the slow TM11 wave, then it gives up longitudinal energy to the same wave with more than 78% efficiency, and an output power up to 30 MW. The developed mathematical model of the interaction of the relativistic electron beam with an irregular circular waveguide and resonator fields presented in this article can be used to calculate and optimize the processes occurring in various microwave electronic devices, such as gyrotrons, gyrotons, TWT, Gyro-TWT, and BWT.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 20
    Publication Date: 2019-02-28
    Description: Studies of the properties of runaway electron preionized diffuse discharges (REP DDs) and their possible use have been carried out for more than 15 years. Three experimental setups generating a low-temperature atmospheric-pressure plasma and differing in the geometry of a discharge gap were developed. They allow the treatment of surfaces of different materials with an area of several tens of square centimeters. A diffuse discharge plasma was formed in the pulse–periodic mode by applying negative voltage pulses with an amplitude of several tens of kilovolts and a duration of 4 ns to a discharge gap with sharply non-uniform electric field strength distribution. This paper presents experimental results of the study of the surface layer microstructure of copper and steel specimens of different sizes after treatment with the REP DD plasma in nitrogen flow mode and nitrogen circulation mode in the discharge chamber. It was shown that after 105 discharge pulses, the carbon concentration decreases and a disoriented surface layer with a depth of up to 200 nm is formed. Moreover, the results of X-ray phase analysis did not reveal changes in the phase composition of the surface of copper specimens. However, as a result of surface treatment with the REP DD plasma, the copper lattice becomes larger and the microstress increases.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 21
    Publication Date: 2019-04-09
    Description: In the gyrokinetic model and simulations, when the double-gyroaverage term incorporates the combining effect contributed by the finite Larmor radius, short scales of the perturbation, and steep gradient of the equilibrium profile, the low-order approximation of this term could generate unignorable error. This paper implements an interpolation algorithm to compute the double-gyroaverage term without low-order approximation to avoid this error. For a steep equilibrium density, the obvious difference between the density on the gyrocenter coordinate frame and the one on the particle coordinate frame should be accounted for in the quasi-neutrality equation. A Euler–Maclaurin-based quadrature integrating algorithm is developed to compute the quadrature integral for the distribution of the magnetic moment. The application of the interpolation algorithm to computing the double-gyroaverage term and to solving the quasi-neutrality equation is benchmarked by comparing the numerical results with the known analytical solutions. Finally, to take advantage of the interpolation solver clearer, the numerical comparison between the interpolation solver and a classical second order solver is carried out in a constant theta-pinch magnetic field configuration using SELALIB code. When the equilibrium profile is not steep and the perturbation only has the non-zero mode number along the parallel spatial dimension, the results computed by the two solvers match each other well. When the gradient of the equilibrium profile is steep, the interpolation solver provides a bigger driving effect for the ion-temperature-gradient modes, which possess large polar mode numbers.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 22
    Publication Date: 2019-07-12
    Description: The rapid advances in the field of cold plasma research led to the development of many plasma jets for various purposes. The COST plasma jet was created to set a comparison standard between different groups in Europe and the world. Its physical and chemical properties are well studied, and diagnostics procedures are developed and benchmarked using this jet. In recent years, it has been used for various research purposes. Here, we present a brief overview of the reported applications of the COST plasma jet. Additionally, we discuss the chemistry of the plasma-liquid systems with this plasma jet, and the properties that make it an indispensable system for plasma research.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 23
    Publication Date: 2019-09-16
    Description: The present work aims to investigate the interaction between a plasma jet and targets with different physical properties. Electrical, morphological and fluid-dynamic characterizations were performed on a plasma jet impinging on metal, dielectric and liquid substrates by means of Intensified Charge-Coupled Device (ICCD) and high-speed Schlieren imaging techniques. The results highlight how the light emission of the discharge, its time behavior and morphology, and the plasma-induced turbulence in the flow are affected by the nature of the target. Surprisingly, the liquid target induces the formation of turbulent fronts in the gas flow similar to the metal target, although the dissipated power in the former case is lower than in the latter. On the other hand, the propagation velocity of the turbulent front is independent of the target nature and it is affected only by the working gas flow rate.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 24
    Publication Date: 2019-04-23
    Description: We investigate the use of a DC-pulse-driven non-thermal atmospheric-pressure He plasma jet in the regulation of hydrogen peroxide (H2O2), nitrite (NO2−), nitrate (NO3−), and oxygen (O2) in deionized (DI) water. The production of these molecules is measured by in situ UV absorption spectroscopy of the plasma-activated water (PAW). Variations in the pulse polarity and pulse width have a significant influence on the resultant PAW chemistry. However, the trends in the concentrations of H2O2, NO2−, NO3−, and O2 are variable, pointing to the possibility that changes in the pulse polarity and pulse width might influence other plasma variables that also impact on the PAW chemistry. Overall, the results presented in this study highlight the possibility of using DC-pulse-driven plasma jets to tailor the chemistry of PAW, which opens new opportunities for the future development of optimal PAW formulations across diverse applications ranging from agriculture to medicine.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 25
    Publication Date: 2019-05-08
    Description: We studied the amplitude modulation of the radial electric field constructed from the Langmuir probe plasma potential measurements at the edge of the mega-ampere spherical tokamak (MAST). The Empirical Mode Decomposition (EMD) technique was applied, which allowed us to extract fluctuations on temporal scales of plasma turbulence, the Geodesic Acoustic Mode (GAM), and those associated with the residual poloidal flows. This decomposition preserved the nonlinear character of the signal. Hilbert transform (HT) was then used to obtain the amplitude modulation envelope of fluctuations associated with turbulence and with the GAM. We found significant spectral coherence at frequencies between 1–5 kHz, in the turbulence and the GAM envelopes and for the signal representing the low frequency zonal flows (LFZFs). We present the evidence of local and nonlocal, in frequency space, three wave interactions leading to coupling between the GAM and the low frequency (LF) part of the spectrum.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 26
    Publication Date: 2019-08-30
    Description: Scientific breakthroughs tend to come in spurts when unique societal, economical, and political circumstances conspire (knowingly or unknowingly) and create an environment ripe for creativity. The field of low temperature plasma (LTP) recently experienced such an upheaval, which this paper attempts to relate in some details. There have been “roadmap” papers published before, which look towards the future of the field, but all roads start somewhere and even “new” roads are often paved over older roads that were discovered and traveled by early pioneers. With the sharp decrease in funding for fusion research in the USA in the early 1990s the plasma science community was faced with a dire situation that threatened to choke off plasma physics advances. However, in the background and far from the visibility accorded to fusion research, a few laboratories were quietly engaged in innovative research that in due time revolutionized the LTP field and breathed new life into plasma science. Groundbreaking applications of LTP were investigated that until today constitute most of the LTP research activities. These innovations spanned a wide spectrum that included the invention of novel devices, improvement of existing ones, and the deployment of these devices to areas ranging from industrial to biomedical applications. These efforts turned out to have impactful scientific and societal implications. In this paper plasma sources and applications developed during this uniquely innovative decade are briefly discussed.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 27
    Publication Date: 2019-08-16
    Description: Inductive plasma discharge has been a part of continuous investigations since it was discovered. Especially the E- to H-mode transition and the hysteresis behavior have been topics of research in the last few decades. In this paper, we demonstrate a way to reduce the hysteresis behavior by the usage of a microwave ignition system. With this system, a significant decrease of the needed coil current for the ignition of the inductive driven plasma is realized. For the microwave generation, a magnetron as in a conventional microwave oven is used, which offers a relatively inexpensive way for microwave ignition aid. At the measured pressure of 7.5 Pa, it was possible to reduce the needed coil current for the inductive mode transition by a factor of 3.75 compared to the mode transition current without the ignition aid. This was achieved by initiating the transition by a few seconds of microwave coupling. The performed simulations suggested that the factor can be further increased at higher pressures. That is especially interesting for plasmas that are hard to ignite or for RF-sources that cannot deliver high enough currents or frequencies for the ignition.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 28
    Publication Date: 2019-03-04
    Description: Understanding the production mechanisms of ozone and other reactive species in atmospheric pressure dielectric barrier discharges (DBDs) has become increasingly important for the optimization and commercial success of these plasma devices in emerging applications, such as plasma medicine, plasma agriculture, and plasma catalysis. In many of these applications, input power modulation is exploited as a means to maintain a low gas temperature. Although the chemical pathways leading to ozone production/destruction and their strong temperature dependence are relatively well understood, the effect of the on-time duration on the performance of these modulated DBDs remains largely unexplored. In this study, we use electrical and optical diagnostics, as well as computational methods, to assess the performance of a modulated DBD device. The well-established Lissajous method for measuring the power delivered to the discharge is not suitable for modulated DBDs because the transients generated at the beginning of each pulse become increasingly important in short on-time modulated plasmas. It is shown that for the same input power and modulation duty-cycle, shorter on-time pulses result in significantly enhanced ozone production, despite their operation at slightly higher temperatures. The key underpinning mechanism that causes this counter-intuitive observation is the more efficient net generation rate of ozone during the plasma on-time due to the lower accumulation of NO2 in the discharge volume.
    Electronic ISSN: 2571-6182
    Topics: Natural Sciences in General
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  • 29
    Publication Date: 2019-07-19
    Description: Analysis of the L–H and H–L transition power thresholds (Pth) and pedestal parameters are presented for the mega ampere spherical tokamak (MAST). The dependencies of Pth on the average, core plasma electron density, X-point height, and plasma current are described. Increasing X-point distance from the divertor floor over 10–12 cm is found to increase Pth by a factor of three, while X-point heights greater than this have no further influence. The X-point height dependence of Pth is also observed to be sensitive to the plasma current. An Ip decrease from 0.77 MA to 0.65 MA, is observed to lower Pth by a factor of three across the X-point height scan and increases the maximum X-point height at which Pth stops increasing by 3 cm. Finally, a comparison of the experimental results with the predictions by the finite beta drift wave model is made, which provides a reasonable condition for the transition into and out of the H-mode.
    Electronic ISSN: 2571-6182
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  • 30
    Publication Date: 2019-03-21
    Description: In the post-transient stage of a 1-Torr pulsed argon discharge, a computationally assisted diagnostic technique is demonstrated for either inferring the electron energy distribution function (EEDF) if the metastable-atom density is known (i.e., measured) or quantitatively determining the metastable-atom density if the EEDF is known. This technique, which can be extended to be applicable to the initial and transient stages of the discharge, is based on the sensitivity of both emission line ratio values to metastable-atom density, on the EEDF, and on correlating the measurements of metastable-atom density, electron density, reduced electric field, and the ratio of emission line pairs (420.1–419.8 nm or 420.1–425.9 nm) for a given expression of the EEDF, as evidenced by the quantitative agreement between the observed emission line ratio and the predicted emission line ratio. Temporal measurement of electron density, metastable-atom density, and reduced electric field are then used to infer the transient behavior of the excitation rates describing electron-atom collision-induced excitation in the pulsed positive column. The changing nature of the EEDF, as it starts off being Druyvesteyn and becomes more Maxwellian later with the increasing electron density, is key to interpreting the correlation and explaining the temporal behavior of the emission line ratio in all stages of the discharge. Similar inferences of electron density and reduced electric field based on readily available diagnostic signatures may also be afforded by this model.
    Electronic ISSN: 2571-6182
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  • 31
    Publication Date: 2019-03-08
    Description: The interaction of powerful sub-picosecond timescale lasers with neutral gas and plasmas has stimulated enormous interest because of the potential to accelerate particles to extremely large energies by the intense wakefields formed and without being limited by high accelerating gradients as in conventional accelerator cells. The interaction of extremely high-power electromagnetic waves with plasmas is though, of general interest and also to plasma heating and wake-field formation. The study of this subject has become more accessible with the availability of sub-nanosecond timescale GigaWatt (GW) power scale microwave sources. The interaction of such high-power microwaves (HPM) with under-dense plasmas is a scale down of the picosecond laser—dense plasma interaction situation. We present a review of a unique experiment in which such interactions are being studied, some of our results so far including results of our numerical modeling. Such experiments have not been performed before, self-channeling of HPM through gas and plasma and extremely fast plasma electron heating to keV energies have already been observed, wakefields resulting from the transition of HPM through plasma are next and more is expected to be revealed.
    Electronic ISSN: 2571-6182
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  • 32
    Publication Date: 2019-05-12
    Description: We present initial results in the development of a gyrokinetic particle-in-cell code for the whole-volume modeling of stellarators. This is achieved through two modifications to the X-point Gyrokinetic Code (XGC), originally developed for tokamaks. One is an extension to three-dimensional geometries with an interface to Variational Moments Equilibrium Code (VMEC) data. The other is a connection between core and edge regions that have quite different field-line structures. The VMEC equilibrium is smoothly extended to the edge region by using a virtual casing method. Non-axisymmetric triangular meshes in which triangle nodes follow magnetic field lines in the toroidal direction are generated for field calculation using a finite-element method in the entire region of the extended VMEC equilibrium. These schemes are validated by basic benchmark tests relevant to each part of the calculation cycle, that is, particle push, particle-mesh interpolation, and field solver in a magnetic field equilibrium of Large Helical Device including the edge region. The developed code also demonstrates collisionless damping of geodesic acoustic modes and steady states with residual zonal flow in the core region.
    Electronic ISSN: 2571-6182
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  • 33
    Publication Date: 2019-04-03
    Description: Acinetobacter baumannii is a typically short, almost round, rod-shaped (coccobacillus) Gram-negative bacterium. It can be an opportunistic pathogen in humans, affecting people with compromised immune systems, and it is becoming increasingly important as a hospital-associated (nosocomial) infection. It has also been isolated from environmental soil and water samples. In this work, unlike conventional medical methods like antibiotics, the influence of atmospheric-pressure cold plasma on this bacterium is evaluated by means of a colony count technique and scanning electron microscopy. The plasma used here refers to streamers axially propagating into a helium channel penetrating the atmospheric air. The plasma is probed with high resolution optical emission spectroscopy and copious reactive species are unveiled under low-temperature conditions. Based on the experimental results, post-treatment (delayed) biochemical effects on Acinetobacter baumannii and morphological modifications appear dominant, leading to complete deactivation of this bacterium.
    Electronic ISSN: 2571-6182
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  • 34
    Publication Date: 2019-07-31
    Description: Low temperature plasma jets are unique plasma sources capable of delivering plasma outside of the confinement of electrodes and away from gas enclosures/chambers [...]
    Electronic ISSN: 2571-6182
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  • 35
    Publication Date: 2019-06-02
    Description: We address the mechanisms underlying low-frequency zonal flow generation in a turbulent system through the parametric decay of collisionless trapped particle modes and its feedback on the stabilization of the system. This model is in connection with the observation of barrier transport in reduced gyrokinetic simulations (A. Ghizzo et al., Euro. Phys. Lett. 119(1), 15003 (2017)). Here the analysis is extended with a detailed description of the resonant mechanism. A key role is also played by an initial polarisation source that allows the emergence of strong initial shear flow. The parametric decay leads to the growth of a zonal flow which differs from the standard zero frequency zonal flow usually triggered by the Reynolds stress in fluid drift-wave turbulence. The resulting zonal flow can oscillate at low frequency close to the ion precession frequency, making it sensitive to strong amplification by resonant kinetic processes. The system becomes then intermittent. These new findings, obtained from numerical experiments based on reduced semi-Lagrangian gyrokinetic simulations, shed light on the underlying physics coming from resonant wave-particle interactions for the formation of transport barriers. Numerical simulations are based on a Hamiltonian reduction technique, including magnetic curvature and interchange turbulence, where both fastest scales (cyclotron and bounce motions) are gyro-averaged.
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  • 36
    Publication Date: 2019-02-22
    Description: We have developed an analytical approach that predicts radial oscillation near theaperture of a pillbox cavity. In addition, it provides natural criteria for the design of a taperedguiding magnetic field in the output section of a relativistic klystron amplifier, as well as that of atravelling wave tube, in a method that is self-consistent with the dynamics of the electrons.
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  • 37
    facet.materialart.
    Unknown
    Molecular Diversity Preservation International
    Publication Date: 2019-01-18
    Description: Rigorous peer-review is the corner-stone of high-quality academic publishing [...]
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  • 38
    Publication Date: 2019-08-22
    Description: The interaction of an atmospheric pressure plasma jet with different dielectric surfaces is investigated using a setup of two ring electrodes around a ceramic capillary. In this study, in addition to electrical measurement methods such as the determination of voltage and current, special emphasis was placed on the power measurements at the electrodes and the effluent. The power dissipation is correlated with Fourier-transform infrared (FTIR) absorption spectroscopy measurements of O3 and NO2 densities. The results show the correlation between the dielectric constant and the dissipated power at the target. The ratio between power dissipation at the grounded ring electrode and the grounded surface shows an increase with increasing dielectric constant of the target. A correlation of the results with bacteria, tissue and water as envisaged dielectric targets shows four times the power dissipation at the treatment spot between bacteria and tissue.
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  • 39
    Publication Date: 2019-09-18
    Description: Sickle cell disease (SCD) is an inherited disorder of major health challenge in Nigeria. Micronutrients deficiencies often associated with the disorder may cause inflammation and abnormal metabolisms in the body. The copper-to-zinc ratio is a more important assessment than the concentrations of either of the metals in clinical practice. This study seeks to evaluate serum levels of c-reactive protein (CRP), copper, zinc and copper-to-zinc ratio and to correlate copper-to-zinc ratio with CRP in adult subjects with SCD. Serum copper, zinc, CRP and plasma fibrinogen were assayed in 100 confirmed SCD patients in steady clinical state and 100 age and sex matched subjects with normal haemoglobin. Serum copper and zinc were assayed by colorimetric method using reagents supplied by Centronic, Germany while CRP and fibrinogen were assayed using reagents supplied by Sigma (St. Louis, MO, USA) and Anogen (Ontario, Canada), respectively. The copper to zinc ratio was calculated from serum levels of copper and zinc. The measured parameters were compared between the groups using Students t-test and Pearson correlation coefficient was used to relate CRP with the other parameters. Serum copper, CRP, fibrinogen and copper-to-zinc ratio were significantly higher (p 〈 0.001) while zinc level was lower in SCD patients than controls. Serum CRP concentration correlated with copper (r = 0.10; p 〈 0.02), zinc (r = −0.199; p 〈 0.05) and Copper-to-zinc ratio (r = 0.312; p 〈 0.002) but the correlation between CRP and fibrinogen was not significant. Inflammatory condition may modulate copper and zinc homeostasis and copper-to-zinc ratio may be used as marker of nutritional deficiency and inflammation in SCD patients.
    Electronic ISSN: 2413-4155
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  • 40
    Publication Date: 2019-03-21
    Description: Endocrine disrupting compounds (EDCs) are contaminants with estrogenic or androgenic activity that negatively impact human and animal communities. These compounds have become one of the significant concerns for wastewater treatment in recent decades. Several studies have evaluated EDC removal methods from wastewater across the globe including the United Kingdom (UK). Accordingly, the current study reviews EDC removal methods from municipal/domestic wastewater in the United Kingdom (UK) for the period of 2010–2017. The research highlights that despite the relative efficacy of existing chemical and physical methods for removing certain EDCs from wastewater there is emerging evidence supporting the need for more widespread application of nature-based and biological approaches, particularly the use of biofilms. The analysis reveals that there have been relatively few research studies on EDC removal methods have been carried out in the UK in the 2010–2017 period and none of the research focused on EDC removal using biofilms. Finally, this review suggests that more research is needed to remove EDCs, particularly through the application of biofilms, from municipal wastewater in current scenarios.
    Electronic ISSN: 2413-4155
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  • 41
    Publication Date: 2019-03-18
    Description: Rapid peri-urbanization has resulted in increasing demand for and pressure on peri-urban lands at the expense of agricultural lands. Households’ decision to convert from agricultural land uses to residential and commercial land uses is driven by a myriad of factors, ranging from social to economic, in the Asante-Akim South district of the Asante region, Ghana. The paper examined the effects of agricultural land use trade-off on food production in the district. Using a triangulation of qualitative and quantitative methods, 115 household respondents were proportionately sampled from three selected communities in the district, for the collection of data through the administration of questionnaires. The data were subjected to the Pearson’s chi-square, embedded in the SPSS V.16, to test for association among the variables. We report that the increasing rate of agricultural land uses conversions was as a result of increasing demand for residential and commercial land usage at the expense of agricultural land uses. Converting prime agricultural lands into other land uses was seen as profitable to agricultural expansion. A re-examination of the district land use plans by the Ghanaian Physical (Town and Country) Planning Department in tandem with the Lands Commission is therefore recommended.
    Electronic ISSN: 2413-4155
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  • 42
    Publication Date: 2019-06-10
    Description: The Affordable Care Act (ACA) is at the crossroads. It is important to evaluate the effectiveness of the ACA in order to make rational decisions about the ongoing healthcare reform, but existing research into its effect on health insurance status in the United States is insufficient and descriptive. Using data from the National Health Interview Surveys from 2009 to 2015, this study examines changes in health insurance status and its determinants before the ACA in 2009, during its partial implementation in 2010–2013, and after its full implementation in 2014 and 2015. The results of trend analysis indicate a significant increase in national health insurance rate from 82.2% in 2009 to 89.4% in 2015. Logistic regression analyses confirm the similar impact of age, gender, race, marital status, nativity, citizenship, education, and poverty on health insurance status before and after the ACA. Despite similar effects across years, controlling for other variables, youth aged 26 or below, the foreign-born, Asians, and other races had a greater probability of gaining health insurance after the ACA than before the ACA; however, the odds of obtaining health insurance for Hispanics and the impoverished rose slightly during the partial implementation of the ACA but somewhat declined after the full implementation of the ACA starting in 2014. These findings should be taken into account by the U.S. government in deciding the fate of the ACA.
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  • 43
    Publication Date: 2019-04-26
    Description: When focusing on materials science in civil engineering, the current trend is to investigate the use of innovative solutions in order to enhance thermal and energy performances. This trend is amplified with the need for a sustainable development strategy for the construction sector. This paper assesses the integration of a Phase Change Material (PCM) in cement intended for building construction. The key characteristic of PCMs is their capacity to absorb energy and restore it. In building construction, this feature could be harnessed to save energy by incorporating PCMs in the materials used. In this study, passive integration of PCM in cement was tested and thermal properties of such an integration was assessed. The results provide insights into how PCMs affect cement as part of the concrete mixture, thus identifying the contribution of PCM-based cements in concrete mixtures.
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  • 44
    Publication Date: 2019-04-09
    Description: Nizatidine is a gastroprotective drug with a short biological half-life and narrow absorption window. This study aimed at developing floating tablets of nizatidine using various HPMC viscosity grades, namely K4M, E4M, K15 and K200M. Directly compressed tablets revealed an excellent uniformity in hardness, thickness and weight and nizatidine was evenly distributed within the matrix floating tablets. Buoyancy study revealed floating lag time as low as 18–38 s, and tablets remain buoyant for upto 24 h. However, the later depended upon viscosity grade of HPMC and that the higher the viscosity, the less was the total floating time. In vitro dissolution indicated viscosity dependent nizatidine release from the floating tablets. HPMC K4M and E4M based floating tablets released almost 100% drug in 12 h, whilst higher viscosity polymers such as K15 and K200M only released 81.88% and 75.81% drug, respectively. The drug release followed non-Fickian diffusion from tablets formulated with K4M, K15 and K200M, whilst super case II transport was observed with E4M based tablets. More interestingly, K4M and E4M polymers have similar viscosity yet exhibited different drug release mechanism. This was attributed to the difference in degree of substitution of methoxyl- and hydroxypropoxyl- groups on polymer backbone.
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  • 45
    Publication Date: 2019-07-09
    Description: Thermoelectrics, in particular solid-state conversion of heat to electricity and vice versa, is expected to be a key energy harvesting and temperature management solution in coming years. There has been a resurgence in the search for new materials for advanced thermoelectric energy conversion applications and to enhance the properties of existing materials. In this paper, we review recent efforts on improving figure-of-merit (ZT) through alloying and nano structuring. As heatsink characteristics dictate the performance of thermoelectric modules, various types of heatsink designs has been investigated. Several reported strategies for improving ZT are critically assessed. A notable increase in figure-of-merit of thermoelectric materials (TE) has opened up new areas of applications especially in the medical field. Peltier cooling devices are widely employed for patient core temperature control, skin cooling, medical device and laboratory equipment cooling. Application of these devices in the medical field both in temperature control and power generation has been studied in detail. It is envisioned that this study will provide profound knowledge on the thermoelectric based materials and its role in medical applications.
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  • 46
    Publication Date: 2019-12-16
    Description: Toll-like receptor 5 ligand, flagellin, and Vascular Adhesion Protein-1 (VAP-1) are involved in non-alcoholic fatty liver disease (NAFLD). This study aimed to determine whether VAP-1 mediates flagellin-induced hepatic fat accumulation. The effects of flagellin on adipocyte VAP-1 expression were first studied in vitro. Then, flagellin (100 ng/mouse) or saline was intraperitoneally injected to C57BL/6J WT and C57BL/6-Aoc3-/- (VAP-1 KO) mice on high-fat diet twice a week every two weeks for 10-weeks. After that, the effects on inflammation, insulin signaling, and metabolism were studied in liver and adipose tissues. Hepatic fat was quantified histologically and biochemically. Because flagellin challenge increased VAP-1 expression in human adipocytes, we used VAP-1 KO mice to determine whether VAP-1 regulates the inflammatory and metabolic effects of flagellin in vivo. In mice, VAP-1 mediated flagellin-induced inflammation, leukocyte infiltration and lipolysis in visceral adipose tissue. Consequently, increased release of glycerol led to hepatic steatosis in WT but not KO mice. Flagellin-induced hepatic fibrosis was not mediated by VAP-1. VAP-1 KO mice harbored more inflammation-related microbes than WT, while flagellin did not affect the gut microbiota. Our results suggest that by acting on visceral adipose tissue, flagellin increased leukocyte infiltration that induced lipolysis. Further, the released glycerol participated in hepatic fat accumulation. In conclusion, the results describe that gut microbial flagellin through VAP-1 induced hepatic steatosis.
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  • 47
    facet.materialart.
    Unknown
    Molecular Diversity Preservation International
    Publication Date: 2019-11-13
    Description: This study analyzes the correlation between the lifetime and the rest energy of the unstable particle states with a lifetime greater than the zeptosecond (10−21 s), using data available from the Particle Data Group. This set of states seems to be divided into three groups, in each of which the two quantities can be correlated through a remarkably accurate power law. Although this fact does not represent anything new compared to the predictions of the Standard Model, it nevertheless reveals an unexpected order structure in the set of particle decays, emerging from such predictions.
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  • 48
    Publication Date: 2019-11-15
    Description: A novel hybrid phosphite (C4H14N2)[Co(H2PO3)4]∙2H2O was synthesized with 1,4-diaminobutane (dabn) as a structure-directing agent using slow evaporation method. Single crystalX-ray diraction analysis showed that it crystallizes in the P-1 triclinic space group, with the following unit cell parameters (Å, °) a = 5.4814 (3), b = 7.5515 (4), c = 10.8548 (6), α = 88.001 (4), β = 88.707 (5), = 85.126 (5), and V= 447.33 (4) Å3. The crystal structure was built up from corner-sharing [CoO6]octahedrons, forming chains parallel to [001], which are interconnected by H2PO3-pseudo-tetrahedral units. The diprotonated 1,4-butanediammonium molecules, residing between the parallel chains, interacted with the inorganic moiety via hydrogen bonds leading thus to the formation of the 3D crystal structure. The Fourier transform infrared spectrum showed characteristic bands corresponding to the phosphite group and the organic molecule. The thermal decomposition of the compound consisted mainly of the loss of the organic moiety and the water molecules. The biological tests exhibited significant activity against Candida albicans and Escherichia coli strains in all used concentrations, while less activity was pronounced when tested against Staphylococcus epidermidis and Saccharomycescerevisiae, while there was no activity against the nematode model Steinernema feltiae.
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  • 49
    Publication Date: 2019-10-19
    Description: Both macro and microprojectiles (e.g., interplanetary, interstellar and even intergalactic material) are seen as important vehicles for the exchange of potential (bio)material within our solar system as well as between stellar systems in our Galaxy. Accordingly, this requires estimates of the impact probabilities for different source populations of projectiles, including for intergalactic meteor particles which have received relatively little attention since considered as rare events (discrete occurrences that are statistically improbable due to their very infrequent appearance). We employ the simple but comprehensive model of intergalactic microprojectile capture by the gravity of exoplanets which enables us to estimate the map of collisional probabilities for an available sample of exoplanets in habitable zones around host stars. The model includes a dynamical description of the capture adopted from Mautner model of interstellar exchange of microparticles and changed for our purposes. We use statistical and information metrics to calculate probability map of intergalactic meteorite particle capture. Moreover, by calculating the entropy index map we estimate the concentration of these rare events. We further adopted a model from immigration theory, to show that the time dependent distribution of single molecule immigration of material indicates high survivability of the immigrated material taking into account birth and death processes on our planet. At present immigration of material can not be observationally constrained but it seems reasonable to think that it will be possible in the near future, and to use it along other proposed parameters for life sustainability on some planet.
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  • 50
    Publication Date: 2019-10-15
    Description: Injuries to the ligaments of the knee are extremely common among athletes who participate in high-risk sports, or any sport that requires frequent cutting motions, jumping, or contact. In order to determine the best way to heal these injuries, it is important to understand not just the pathology of the injury, but also the biomechanical factors that are affected, including stability and steadiness. While many studies have been done to examine the stability of healthy knees, there is little to no existing literature on stability of knees afflicted by injury. In order to surpass this obstacle, static steadiness and dynamic stability data was collected using the Lockhart Monitor phone application and Xsens accelerometers, respectively, both before and after completion of a course of physical therapy in a patient with a grade 2 medial collateral ligament (MCL) tear. These results were then used to determine the degree to which the prescribed physical therapy protocol was effective in healing the MCL, which can be useful for tweaking the individual protocol for future conservative treatment and management of the injury.
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  • 51
    Publication Date: 2019-10-06
    Description: It is proposed that the primary living cells (“probionts”) cannot emerge of organic substance simply by continuous chemical complication of prebiotic macromolecules and microsystems. The complication must be accompanied by the radical thermodynamic transformation (“jump”) of prebiotic microsystems that resulted in the acquired ability to extract free energy from the environment and export entropy. This transformation is called “the thermodynamic inversion” The inversion may occur by means of the efficient (intensified) response of the microsystems on the oscillations of physic-chemical parameters in hydrothermal environment. In this case the surplus available free energy within a microsystem, when combined with the informational modality, facilitates its conversion into a new microsystem—a living probiont. It is shown the schematic representation of an oscillating prebiotic microsystem that is transforming into a living probiont. A new kind of laboratory and computational experiments on prebiotic chemistry under oscillating conditions is offered to verify the inversion concept.
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  • 52
    facet.materialart.
    Unknown
    Molecular Diversity Preservation International
    Publication Date: 2019-10-10
    Description: This study analyzes the correlation between the lifetime and the rest energy of the unstable particle states with a lifetime greater than the zeptosecond (10−21 s), using data available from the Particle Data Group. This set of states seems to be divided into three groups, in each of which the two quantities can be correlated through a remarkably accurate power law. Although this fact does not represent anything new compared to the predictions of the Standard Model, it nevertheless reveals an unexpected order structure in the set of particle decays, emerging from such predictions.
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  • 53
    Publication Date: 2019-08-07
    Description: An endemic pear species spreads in one region of western Georgia, Adjara, called Khechechuri. Pears are dietary source of bioactive components such as polyphenols and triterpenic acid. In addition to its gastronomic value, the aim of the article was to examine and compare phenolic compounds, flavonoids, catechins, phenolic acids, and antioxidant activities in five species of Khechechuri collected from various regions in Adjara region: Adjaristskali, Merisi, Dandalo, Shuakhevi, and Khulo. Five fruit parts, the skin, edible pulp, the whole pear (skin + pulp), juice and the pomace were analyzed and the results were compared. Our study revealed that the amount of total phenolic content found in the skin of West Georgian pear types was as much as 4650 mg/kg. Also, the pear pomace showed significant amount of total phenolic content in all species of Khechechuri. In addition, in all species of Khechechuri pears, flavonoids were found, except in the fruit juice.
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  • 54
    Publication Date: 2019-02-28
    Description: In the present study Aprepitant (APT) ternary solid dispersions (SDs) were developed and evaluated for the first time. Specifically, ternary SDs of APT with Poloxamer 188 and Soluplus® (SOL) were prepared via melt mixing and compared to binary APT/Poloxamer 188 and APT/SOL SDs. Initially, combined thermo-gravimetric and hot-stage polarized light microscopy studies indicated that all tested compounds were thermally stable up to 280 °C, while Poloxamer 188 acted as a plasticizer to SOL by significantly reducing the temperature required to fully solubilize the API during SD preparation. Differential scanning calorimetry combined with wide angle X-ray diffraction studies showed that crystalline API was dispersed in both binary and ternary SDs, while Fourier transformation-infrared spectroscopy studies revealed no molecular interactions among the components. Scanning electron microscopy combined with EDAX element analysis showed that the API was dispersed in nano-scale within the polymer matrices, while increasing APT content led to increasing API nano-crystals within the SDs. Finally, dissolution studies showed that the prepared formulations enhanced dissolution of Aprepitant and its mechanism analysis was further studied. A mathematical model was also investigated to evaluate the drug release mechanism.
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  • 55
    Publication Date: 2019-06-10
    Description: In the present study Aprepitant (APT) ternary solid dispersions (SDs) were developed and evaluated for the first time. Specifically, ternary SDs of APT with Poloxamer 188 and Soluplus® (SOL) were prepared via melt mixing and compared to binary APT/Poloxamer 188 and APT/SOL SDs. Initially, combined thermo-gravimetric and hot-stage polarized light microscopy studies indicated that all tested compounds were thermally stable up to 280 °C, while Poloxamer 188 acted as a plasticizer to SOL by significantly reducing the temperature required to fully solubilize the API during SD preparation. Differential scanning calorimetry combined with wide angle X-ray diffraction studies showed that crystalline API was dispersed in both binary and ternary SDs, while Fourier transformation-infrared spectroscopy studies revealed no molecular interactions among the components. Scanning electron microscopy combined with EDAX element analysis showed that the API was dispersed in nano-scale within the polymer matrices, while increasing APT content led to increasing API nano-crystals within the SDs. Finally, dissolution studies showed that the prepared formulations enhanced dissolution of Aprepitant and its mechanism analysis was further studied. A mathematical model was also investigated to evaluate the drug release mechanism
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  • 56
    Publication Date: 2019-04-17
    Description: When a railway vehicle moves on a curved rail, sliding contact occurs between the rail head side and wheel flange, which wears the wheel flange down. The thinned flange needs to be restored above the required minimum thickness for structural safety. In this study, a new process and welding wire for restoring worn-out railway wheels by submerged arc welding was developed. To characterize the properties of the restored wheel, dilatometric analysis of phase transformation, SEM/EDX analyses, hardness measurement, and residual stress measurement using the X-ray diffraction method were performed. Finally, wear tests with full-size wheel/rail specimens were carried out. It was confirmed that the weld metal was composed of bainitic microstructures as intended, and welding defects were not observed. The wear amount of the restored wheel was greater than that of the base material, but it was less than half of the wear depth of the weld-repaired wheel with ferritic–pearlitic microstructures. The developed process seems applicable to industry.
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  • 57
    Publication Date: 2019-04-17
    Description: As there is lack of understanding about the effect of transitioning between different flooring materials on the gait of older adults, this study investigated the effect of transitioning between a carpeted floor and a vinyl floor on the gait characteristics of older adults. Fourteen older (65 years old and over) and 14 younger (18 to 35 years old) adults walked on different transitional floors by measuring various gait parameters. While the older participants had greater toe clearance than their younger counterparts, the older participants had smaller toe clearance on a carpeted floor than on a vinyl floor, which would increase the probability of a trip-induced fall. Further, the study found the slower transitional acceleration of the whole body COM and the increased friction demand, especially during the toe-off phase, rather than heel contact phase, which will lead to a slip-induced fall on a vinyl floor shortly after transitioning from a carpeted floor to a vinyl floor. Although the increased likelihood of a slip or trip accident was found throughout the changes in gait parameters, the older participants did not perceive of slipping and tripping much. Therefore, the elderly are recommended to be made aware of the danger of slipping and tripping while transitioning between different flooring materials.
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  • 58
    Publication Date: 2019-02-13
    Description: We tested the hypothesis that concatemers of ancestral tRNAs gave rise to the 16S ribosomal RNA. We built an ancestral sequence of proto-tRNAs that showed a significant identity of 51.69% and a percentage of structural identity of 0.941 with the 16S ribosomal molecule. We also propose a hypothesis for the emergence of translation.
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  • 59
    facet.materialart.
    Unknown
    Molecular Diversity Preservation International
    Publication Date: 2019-03-21
    Description: Background: Previous papers have developed a statistical mechanics of neocortical interactions (SMNI) fit to short-term memory and EEG data. Adaptive Simulated Annealing (ASA) has been developed to perform fits to such nonlinear stochastic systems. An N-dimensional path-integral algorithm for quantum systems, qPATHINT, has been developed from classical PATHINT. Both fold short-time propagators (distributions or wave functions) over long times. Previous papers applied qPATHINT to two systems, in neocortical interactions and financial options. Objective: In this paper the quantum path-integral for Calcium ions is used to derive a closed-form analytic solution at arbitrary time that is used to calculate interactions with classical-physics SMNI interactions among scales. Using fits of this SMNI model to EEG data, including these effects, will help determine if this is a reasonable approach. Method: Methods of mathematical-physics for optimization and for path integrals in classical and quantum spaces are used for this project. Studies using supercomputer resources tested various dimensions for their scaling limits. In this paper the quantum path-integral is used to derive a closed-form analytic solution at arbitrary time that is used to calculate interactions with classical-physics SMNI interactions among scales. Results: The mathematical-physics and computer parts of the study are successful, in that there is modest improvement of cost/objective functions used to fit EEG data using these models. Conclusions: This project points to directions for more detailed calculations using more EEG data and qPATHINT at each time slice to propagate quantum calcium waves, synchronized with PATHINT propagation of classical SMNI.
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  • 60
    Publication Date: 2019-09-04
    Description: When a railway vehicle moves on a curved rail, sliding contact occurs between the rail head side and wheel flange, which wears the wheel flange down. The thinned flange needs to be restored above the required minimum thickness for structural safety. In this study, a new process and welding wire for restoring worn-out railway wheels by submerged arc welding was developed. To characterize the properties of the restored wheel, dilatometric analysis of phase transformation, SEM/EDX analyses, hardness measurement, and residual stress measurement using the X-ray diffraction method were performed. Finally, wear tests with full-size wheel/rail specimens were carried out. It was confirmed that the weld metal was composed of bainitic microstructures as intended, and welding defects were not observed. The wear amount of the restored wheel was greater than that of the base material, but it was less than half of the wear depth of the weld-repaired wheel with ferritic–pearlitic microstructures. The developed process seems applicable to industry.
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  • 61
    Publication Date: 2019-03-12
    Description: A novel hybrid phosphite [(C4N2H14)Co(H2PO3)4·2H2O] was synthesized with 1,4- diaminobutane (dabn) as a structure-directing agent using slow evaporation method. Single crystal X-ray diffraction analysis showed that it crystallizes in the triclinic system (S.G: P-1, #2) with the following unit cell parameters (Å, °) a = 5.4814 (3), b = 7.5515 (4), c = 10.8548 (6), α = 88.001 (4), β = 88.707 (5), γ = 85.126 (5). The crystal structure was built up from corner-sharing [CoO6]-octahedrons, forming chains parallel to [001], which are interconnected by H2PO3 pseudo-pyramid units. The diprotonated 1,4-diaminobutane molecules, residing between the parallel chains, interacted with the inorganic moiety via hydrogen bonds leading thus to the formation of the 3D crystal structure. The Fourier transform infrared result exhibited characteristic bands corresponding to the phosphite group and the organic molecule. The thermal decomposition of the compound consists mainly of the loss of the organic moiety and the water molecules. The biological tests exhibited significant activity against Candida albicans and Escherichia coli strains in all used concentrations, while less activity was pronounced when tested against Staphylococcus epidermidis and Saccharomyces cerevisiae, while there was no activity against the nematode model Steinernema feltiae.
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  • 62
    Publication Date: 2019-08-16
    Description: Forces and mechanical energy are prevalent in living cells. This may be because forces and mechanical energy preceded chemical energy at life’s origins. Mechanical energy is more readily available in non-living systems than the various other forms of energy used by living systems. Two possible prebiotic environments that might have provided mechanical energy are hot pools that experience wet/dry cycles and mica sheets as they move, open and shut, as heat pumps or in response to water movements.
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  • 63
    Publication Date: 2019-08-16
    Description: The seeds of red clover are heteromorphic and two color morphs can be visually recognized, light purple and yellow, resulting from heterozygosity and recessive homozygosity at two loci. Here, we report the responses of seed imbibition, seed germination, and early seedling growth of the two morphs to distilled water, sodium chloride, and complete nutrient solution. The sensitivityof red clover seeds to treatments increased with the stage of development in what seems to be a cumulative process. No differences were found in seed imbibition between morphs or between treatments. In seedling growth, on the contrary, treatments were always effective, but differences between morphs were only observed in seeds that were treated with nutrient solution, whereas in the intermediate stage of seed germination, the effects by treatments were observed together with the appearance of differences between morphs in distilled water and in the treatment by sodium chloride solution. Simultaneously, the superior performance of the yellow morph that was found in germination, which appears to be a trait stable across cultivars of red clover seeds, turned into a superior performance of the light purple morph in seedling growth.
    Electronic ISSN: 2413-4155
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  • 64
    Publication Date: 2019-01-02
    Description: The crucial stages in the geochemical evolution of the Earth’s crust, ocean, and atmosphere could be explained by the assumed low-energy nuclear reactions (LENR) that are triggered by seismic activity. LENR result in the fission of medium-weight elements accompanied by neutron emissions, involving Fe and Ni as starting elements, and C, N, O as resultants. Geochemical data and experimental evidences support the LENR hypothesis. A spectral analysis of the period 1955-2013 shows common cycles between interannual changes in atmospheric CO2 growth rate and global seismic-moment release, whereas the trending behavior of the atmospheric CO2 was in response to the anthropogenic emissions. Assuming a correlation between such seismic and atmospheric fluctuations, the latter could be explained by cycles of worldwide seismicity, which would trigger massively LENR in the Earth’s Crust. In this framework, LENR from active faults could be considered as a relevant cause of carbon formation and degassing of freshly-formed CO2 during seismic activity. However, further studies are necessary to validate the present hypothesis which, at the present time, mainly aims to stimulate debate on the models which regulates atmospheric CO2.
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  • 65
    Publication Date: 2019-09-13
    Description: A prime site of astrobiological interest within the Solar System is the interior ocean of Enceladus. This ocean has already been shown to contain organic molecules and is thought to have the conditions necessary for more complex organic biomolecules to emerge and potentially even life itself. This sub-surface ocean has been accessed by Cassini, an unmanned spacecraft that interacted with the water plumes ejected naturally from Enceladus. The encounter speed with these plumes and their contents was 5 km s−1 and above. Encounters at such speeds allow analysis of vaporised material from submicron-sized particles within the plume, but sampling micron-sized particles remains an open question. The latter particles can impact metal targets exposed on the exterior of future spacecraft, producing impact craters lined with impactor residue, which can then be analysed. Although there is considerable literature on how mineral grains behave in such high-speed impacts, and also on the relationship between the crater residue and the original grain composition, far less is known regarding the behaviour of organic particles. Here we consider a deceptively simple yet fundamental scientific question: for impacts at speeds of around 5–6 kms−1 would the impactor residue alone be sufficient to enable us to recognise the signature conferred by organic particles? Furthermore, would it be possible to identify the organic molecules involved, or at least distinguish between aromatic and aliphatic chemical structures? For polystyrene (aromatic-rich) and poly (methyl methacrylate) (solely aliphatic) latex particles impinging at around 5 km s−1 onto metal targets, we found that sufficient residue is retained at the impact site to permit identification of a carbon-rich projectile, but not of the particular molecules involved, nor is it currently possible to discriminate between aromatic-rich and solely aliphatic particles. This suggests that an alternative analytical method to simple impacts on metal targets is required to enable successful collection of organic samples in a fly-by Enceladus mission.
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  • 66
    Publication Date: 2019-08-07
    Description: Because of the near-term risk of extreme weather events and other adverse consequences from climate change, and, at least in the longer term, global fossil fuel depletion, there is world-wide interest in shifting to noncarbon energy sources, especially renewable energy (RE). Because of possible limitations on conventional renewable energy sources, researchers have looked for ways of overcoming these shortcomings by introducing radically new energy technologies. The largest RE source today is bioenergy, while solar energy and wind energy are regarded as having the largest technical potential. This paper reviews the literature on proposed new technologies for each of these three RE sources: microalgae for bioenergy, photolysis and airborne wind turbines. The main finding is that their proponents have underestimated the difficulties facing their introduction on a very large scale.
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  • 67
    Publication Date: 2019-08-08
    Description: This research work investigates the possibility of shielding gravity. The ultimate purpose of this work is to understand the reality behind the concept of Gravitational Shielding (GS) and time dilation. Since the 19th century, scientists have tried to arrive at an understanding of GS via the use of various experiments. Unfortunately, some experiments failed to prove the existence of gravitational shielding, whereas some results proclaimed the possibility of attaining GS. The original phenomenon exhibited by nature cannot easily be understood, but some experiments have demonstrated that the answer may lie behind the mysterious GS. If GS is proved, then in the future, it would be possible to travel across black holes by defying gravity or through any bigger mass having high gravitational field. To unravel the mystery of GS, this work investigates the history of GS and considers the future vision of technologically advanced spacecraft or other warp drive mechanisms with appropriate gravitational shielding. Though the problem is very complex, this research work tries to come to a deeper understanding and explanation of the complexity involved in achieving gravitational shielding.
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  • 68
    facet.materialart.
    Unknown
    Molecular Diversity Preservation International
    Publication Date: 2019-07-25
    Description: How did life begin on Earth? And is there life elsewhere in the Cosmos? Challenging questions, indeed. The series of conferences established by NoR CEL in 2013, addresses these very same questions. The basis for this paper is the summary report of oral presentations that were delivered by NoR CEL’s network members during the 2018 Athens conference and, as such, disseminates the latest research which they have put forward. More in depth material can be found by consulting the contributors referenced papers. Overall, the outcome of this conspectus on the conference demonstrates a case for the existence of “probable chemistry” during the prebiotic epoch.
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  • 69
    Publication Date: 2019-08-09
    Description: We tested the hypothesis that concatemers of ancestral tRNAs gave rise to the 16S ribosomal RNA. We built an ancestral sequence of proto-tRNAs that showed a significant identity of 51.69% and a percentage of structural identity of 0.941 with the 16S ribosomal molecule. We also propose a hypothesis for the emergence of translation.
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  • 70
    Publication Date: 2019-08-09
    Description: Both macro and microprojectiles (e.g., interplanetary, interstellar and even intergalactic material)are seen as important vehicles for the exchange of potential (bio)material within our solar system as wellas between stellar systems in our Galaxy. Accordingly, this requires estimates of the impact probabilitiesfor different source populations of projectiles, including for intergalactic meteor particles which havereceived relatively little attention since considered as rare events (discrete occurrences that are statisticallyimprobable due to their very infrequent appearance). We employ the simple but yet comprehensivemodel of intergalactic microprojectile capture by the gravity of exoplanets which enables us to estimatethe map of collisional probabilities for an available sample of exoplanets in habitable zones around hoststars. The model includes a dynamical description of the capture adopted from Mautner model ofinterstellar exchange of microparticles and changed for our purposes. We use statistical and informationmetrics to calculate probability map of intergalactic meteorite particle capture. Moreover, by calculatingthe entropy index map we measure the concentration of these rare events. We further adopted a modelfrom immigration theory, to show that the transient distribution of birth/death/immigration of materialfor the simplest case has a high value.
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  • 71
    Publication Date: 2019-08-14
    Description: Study of spatiotemporal dynamics of temperature is vital to assess changes in climate, especially in the Himalayan region where livelihoods of billions of people living downstream depends on water coming from the melting of snow and glacier ice. To this end, temperature trend analysis is carried out in Narayani river basin, a major river basin of Nepal characterized by three climatic regions: tropical, subtropical and alpine. Temperature data from six stations located within the basin were analyzed. The elevation of these stations ranges from 460 to 3800 m a.s.l. and the time period of available temperature data ranges from 1960–2015. Multiple regression and empirical mode decomposition (EMD) methods were applied to fill in missing data and to detect trends. Annual as well as seasonal trends were analyzed and a Mann-Kendall test was employed to test the statistical significance of detected trends. Results indicate significant cooling trends before 1970s, and warming trends after 1970s in the majority of the stations. The warming trends range from 0.028 ∘C year−1 to 0.035 ∘C year−1 with a mean increasing trend of 0.03 ∘C year−1 after 1971. Seasonal trends show highest warming trends in the monsoon season followed by winter, pre-monsoon, and the post-monsoon season. However, difference in warming rates between different seasons was not significant. An average temperature lapse rate of −0.006 ∘C m−1 with the steepest value (−0.0064 ∘C m−1) in pre-monsoon season and least negative (−0.0052 ∘C m−1) in winter season was observed for this basin. A comparative analysis of the gap-filled data with freely available global climate datasets show reasonable correlation thus confirming the suitability of the gap filling methods.
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  • 72
    Publication Date: 2019-08-15
    Description: In the present study Aprepitant (APT) ternary solid dispersions (SDs) were developed and evaluated for the first time. Specifically, ternary SDs of APT with Poloxamer 188 and Soluplus® (SOL) were prepared via melt mixing and compared to binary APT/Poloxamer 188 and APT/SOL SDs. Initially, combined thermo-gravimetric and hot-stage polarized light microscopy studies indicated that all tested compounds were thermally stable up to 280 °C, while Poloxamer 188 acted as a plasticizer to SOL by significantly reducing the temperature required to fully solubilize the API during SD preparation. Differential scanning calorimetry combined with wide angle X-ray diffraction studies showed that crystalline API was dispersed in both binary and ternary SDs, while Fourier transformation-infrared spectroscopy studies revealed no molecular interactions among the components. Scanning electron microscopy combined with EDAX element analysis showed that the API was dispersed in nano-scale within the polymer matrices, while increasing APT content led to increasing API nano-crystals within the SDs. Finally, dissolution studies showed that the prepared formulations enhanced dissolution of Aprepitant and its mechanism analysis was further studied. A mathematical model was also investigated to evaluate the drug release mechanism.
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  • 73
    Publication Date: 2019-07-04
    Description: Sickle cell disease (SCD) is an inherited disorder of major health challenge in Nigeria. Micronutrients deficiencies often associated with the disorder may cause inflammation and abnormal metabolisms in the body. The copper-to-zinc ratio is a more important assessment than the concentrations of either of the metals in clinical practice. This study seeks to evaluate serum levels of c-reactive protein (CRP), copper, zinc and copper-to-zinc ratio and to correlate copper-to-zinc ratio with CRP in adult subjects with SCD. Serum copper, zinc, CRP and plasma fibrinogen were assayed in 100 confirmed SCD patients in steady clinical state and 100 age and sex matched subjects with normal haemoglobin. Serum copper and zinc were assayed by colorimetric method using reagents supplied by Centronic, Germany while CRP and fibrinogen were assayed using reagents supplied by Sigma (St. Louis, MO, USA) and Anogen (Ontario, Canada), respectively. The copper to zinc ratio was calculated from serum levels of copper and zinc. The measured parameters were compared between the groups using Students t-test and Pearson correlation coefficient was used to relate CRP with the other parameters. Serum copper, CRP, fibrinogen and copper-to-zinc ratio were significantly higher (p 〈 0.001) while zinc level was lower in SCD patients than controls. Serum CRP concentration correlated with copper (r = 0.10; p 〈 0.02), zinc (r = −0.199; p 〈 0.05) and Copper-to-zinc ratio (r = 0.312; p 〈 0.002) but the correlation between CRP and fibrinogen was not significant. Inflammatory condition may modulate copper and zinc homeostasis and copper-to-zinc ratio may be used as marker of nutritional deficiency and inflammation in SCD patients.
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  • 74
    Publication Date: 2019-07-09
    Description: Study of spatiotemporal dynamics of temperature is vital to assess changes in climate, especially in the Himalayan region where livelihoods of billions of people living downstream depends on water coming from the melting of snow and glacier ice. To this end, temperature trend analysis is carried out in Narayani river basin, a major river basin of Nepal characterized by three climatic regions: tropical, subtropical and alpine. Temperature data from six stations located within the basin were analyzed. The elevation of these stations ranges from 460 to 3800 m a.s.l. and the time period of available temperature data ranges from 1960–2015. Multiple regression and empirical mode decomposition (EMD) methods were applied to fill in missing data and to detect trends. Annual as well as seasonal trends were analyzed and a Mann-Kendall test was employed to test the statistical significance of detected trends. Results indicate significant cooling trends before 1970s, and warming trends after 1970s in the majority of the stations. The warming trends range from 0.028 °C year−1 to 0.035 °C year−1 with a mean increasing trend of 0.03 °C year−1 after 1971. Seasonal trends show highest warming trends in the monsoon season followed by winter, pre-monsoon, and the post-monsoon season. However, difference in warming rates between different seasons was not significant. An average temperature lapse rate of −0.006 °C m−1 with the steepest value (−0.0064 °C m−1) in pre-monsoon season and least negative (−0.0052 °C m−1) in winter season was observed for this basin. A comparative analysis of the gap-filled data with freely available global climate datasets shows reasonable correlation thus confirming the suitability of the gap filling methods.
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  • 75
    Publication Date: 2019-07-15
    Description: Both macro and microprojectiles (e.g., interplanetary, interstellar and even intergalactic material) are seen as an important vehicle for the exchange of (bio)material within our solar system as well as between stellar systems in our Galaxy. Accordingly, this requires estimates of the impact probabilities for different source populations of projectiles, specifically for intergalactic meteor particles which have received relatively little attention since considered as rare events (discrete occurrences that are statistically improbable due to their very infrequent appearance). We employ the simple but yet comprehensive model of intergalactic microprojectile capture by the gravity of exoplanets which enables us to estimate the map of collisional probabilities for an available sample of exoplanets in habitable zones around host stars. The model includes a dynamical description of the caption adopted from Mautner model of interstellar exchange of microparticles and changed for our purposes. We use statistical and information metrics to calculate probability map of intergalactic meteorite particle capture. Moreover, by calculating the entropy index map we measure the concentration of these rare events. By adopting a model from immigration theory, we show that the transient distribution of birth/death/immigration of material for the simplest case has a high value.
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  • 76
    Publication Date: 2019-03-27
    Description: n/a
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  • 77
    Publication Date: 2019-02-28
    Description: The seeds of red clover are heteromorphic and two color morphs can be visually recognized, light purple and yellow, resulting from heterozygosity and recessive homozygosity at two loci. Here, we report the responses of seed imbibition, seed germination, and early seedling growth of the two morphs to distilled water, sodium chloride, and complete nutrient solution. The sensitivity of red clover seeds to treatments increased with the stage of development in what seems to be a cumulative process. No differences were found in seed imbibition between morphs or between treatments. In seedling growth, on the contrary, treatments were always effective, but differences between morphs were only observed in seeds that were treated with nutrient solution, whereas in the intermediate stage of seed germination, the effects by treatments were observed together with the appearance of differences between morphs in distilled water and in the treatment by sodium chloride solution. Simultaneously, the superior performance of the yellow morph that was found in germination, which appears to be a trait stable across cultivars of red clover seeds, turned into a superior performance of the light purple morph in seedling growth.
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  • 78
    Publication Date: 2019-07-04
    Description: It is proposed that the primary living cells (“probionts”) cannot emerge of organic substance simply by continuous chemical complication of prebiotic macromolecules and microsystems. The complication must be accompanied by the radical thermodynamic transformation (“jump”) of prebiotic microsystems that resulted in the acquired ability to extract free energy from the environment and export entropy. This transformation is called “the thermodynamic inversion” The inversion may occur by means of the efficient (intensified) response of the microsystems on the oscillations of physic-chemical parameters in hydrothermal environment. In this case the surplus available free energy within a microsystem, when combined with the informational modality, facilitates its conversion into a new microsystem—a living probiont. It is shown the schematic representation of an oscillating prebiotic microsystem that is transforming into a living probiont. A new kind of laboratory and computational experiments on prebiotic chemistry under oscillating conditions is offered to verify the inversion concept.
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  • 79
    Publication Date: 2019-07-08
    Description: To date, countless satellite image fusions have been made, mainly with panchromatic spatial resolution to a multispectral image ratio of 1/4, fewer fusions with lower ratios, and relatively recently fusions with much higher spatial resolution ratios have been published. Apart from this, there is a small number of publications studying the fusion of aerial photographs with satellite images, with the year of image acquisition varying and the dates of acquisition not mentioned. In addition, in these publications, either no quantitative controls are performed on the composite images produced, or the aerial photographs are recent and colorful and only the RGB bands of the satellite images are used for data fusion purposes. The objective of this paper is the study of the addition of multispectral information from satellite images to black and white aerial photographs of the 2nd half of the 20th century (1950–1999) with small difference (just a few days) in their image acquisition date, the same year and season. Quantitative tests are performed in two case studies and the results are encouraging, as the accuracy of the classification of the features and objects of the Earth’s surface is improved and the automatic digital extraction of their form and shape from the archived aerial photographs is now allowed. This opens up a new field of use for the black and white aerial photographs and archived multispectral satellite images of the same period in a variety of applications, such as the temporal changes of cities, forests and archaeological sites.
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  • 80
    Publication Date: 2019-01-02
    Description: The crucial stages in the geochemical evolution of the Earth’s crust, ocean, and atmosphere could be explained by the assumed low-energy nuclear reactions (LENR) that are triggered by seismic activity. LENR result in the fission of medium-weight elements accompanied by neutron emissions, involving Fe and Ni as starting elements, and C, N, O as resultants. Geochemical data and experimental evidences support the LENR hypothesis. A spectral analysis of the period 1955-2013 shows common cycles between interannual changes in atmospheric CO2 growth rate and global seismic-moment release, whereas the trending behavior of the atmospheric CO2 was in response to the anthropogenic emissions. Assuming a correlation between such seismic and atmospheric fluctuations, the latter could be explained by cycles of worldwide seismicity, which would trigger massively LENR in the Earth’s Crust. In this framework, LENR from active faults could be considered as a relevant cause of carbon formation and degassing of freshly-formed CO2 during seismic activity. However, further studies are necessary to validate the present hypothesis which, at the present time, mainly aims to stimulate debate on the models which regulates atmospheric CO2.
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  • 81
    Publication Date: 2019-07-25
    Description: A novel hybrid phosphite (C4N2H14)[Co(H2PO3)4]·2H2O was synthesized with 1,4- diaminobutane (dabn) as a structure-directing agent using slow evaporation method. Single crystal X-ray diffraction analysis showed that it crystallizes in the P-1 triclinic space group, with the following unit cell parameters (Å, °) a = 5.4814 (3), b = 7.5515 (4), c = 10.8548 (6), α = 88.001 (4), β = 88.707 (5), γ = 85.126 (5), and V = 447.33 (4) Å3. The crystal structure was built up from corner-sharing [CoO6]-octahedrons, forming chains parallel to [001], which are interconnected by H2PO3− pseudo-tetrahedral units. The diprotonated 1,4-butanediammonium molecules, residing between the parallel chains, interacted with the inorganic moiety via hydrogen bonds leading thus to the formation of the 3D crystal structure. The Fourier transform infrared spectrum showed characteristic bands corresponding to the phosphite group and the organic molecule. The thermal decomposition of the compound consisted mainly of the loss of the organic moiety and the water molecules. The biological tests exhibited significant activity against Candida albicans and Escherichia coli strains in all used concentrations, while less activity was pronounced when tested against Staphylococcus epidermidis and Saccharomyces cerevisiae, while there was no activity against the nematode model Steinernema feltiae.
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  • 82
    Publication Date: 2019-07-10
    Description: Li2TiO3 nanopowders were synthesized by hydrothermal process using anatase TiO2 and LiOH H2O as raw materials. Li2TiO3 crystallizes in the layered monoclinic structure (space group C2/c) with average crystallite size of 34 nm. Morphology, elemental composition and local structure of products were carried out using HRTEM, FESEM, EDS, Raman and FTIR spectroscopy. Transport properties investigated by d.c. (4-probe measurements) and a.c. (complex impedance spectroscopy) show the activation energy of 0.71 and 0.65 eV, respectively. The ionic transport properties of Li+ ions in nanocrystalline Li2TiO3 characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) validate the good electrochemical properties of this anode material for lithium-ion batteries.
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  • 83
    Publication Date: 2019-06-21
    Description: The seeds of red clover are heteromorphic and two color morphs can be visually recognized, light purple and yellow, resulting from heterozygosity and recessive homozygosity at two loci. Here, we report the responses of seed imbibition, seed germination, and early seedling growth of the two morphs to distilled water, sodium chloride, and complete nutrient solution. The sensitivity of red clover seeds to treatments increased with the stage of development in what seems to be a cumulative process. No differences were found in seed imbibition between morphs or between treatments. In seedling growth, on the contrary, treatments were always effective, but differences between morphs were only observed in seeds that were treated with nutrient solution, whereas in the intermediate stage of seed germination, the effects by treatments were observed together with the appearance of differences between morphs in distilled water and in the treatment by sodium chloride solution. Simultaneously, the superior performance of the yellow morph that was found in germination, which appears to be a trait stable across cultivars of red clover seeds, turned into a superior performance of the light purple morph in seedling growth.
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  • 84
    Publication Date: 2019-09-16
    Description: We address the need for a model by considering two competing theories regarding the origin of life: (i) the Metabolism First theory and (ii) the RNA World theory. We discuss two inter-related points. (I) Models are valuable tools in understanding both the processes and intricacies of the origin of life issues. (II) Insights from models also help us to evaluate the core objection to origin of life theories called “the inefficiency objection” commonly raised by proponents of both the Metabolism First theory and the RNA World theory against each other. We use Simpson’s paradox as a tool for challenging this objection. We will use models in various senses ranging from taking them as representations of reality to treating them as theories/accounts that provide heuristics for probing reality. In this paper, we will frequently use models and theories interchangeably. Additionally, we investigate Conway’s Game of Life and contrast it with our Simpson’s Paradox (SP)-based approach to emergence of life issues. Finally, we discuss some of the consequences of our view. A scientific model is testable in three senses: (i) a logical sense, (ii) a nomological sense, and (iii) a current technological sense. The SP-based model is testable in the logical sense. It is also testable nomologically. However, it is not currently feasible to test it.
    Electronic ISSN: 2413-4155
    Topics: Natural Sciences in General
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  • 85
    Publication Date: 2019-02-14
    Description: Biodiversity conservation planning is highly important in the current context of global change. Biodiversity conservation can be achieved by understanding changes in land use at the landscape scale. Such understanding is needed to reverse the unprecedented pressure on natural resources that has been reported by many studies conducted on biodiversity conservation within the Oti-Keran-Mandouri protected areas. Land cover maps reflecting different dates (1987, 2000, and 2013) and depicting different management systems, with overall accuracy ranging from 73% to 79%, were analyzed to understand the processes that lead to habitat degradation within these protected areas. The nature of change, within a given land cover class, was determined by comparing land cover maps on different dates using a decision tree algorithm that compares the number of patches, their areas, and their perimeters at different time periods (T1 and T2). Specifically, two time-periods were considered for this analysis: 1987–2000 and 2000–2013. Croplands and settlements increased at an average of 108.13% and 5.45%, respectively, from 1987 to 2000. From 2000 to 2013, croplands gained from all other land categories and continued to increase at a rate of 11.77% per year, whereas forests and savannas decreased at an annual average rate by 5.79% and 2.32%, respectively. The dominant processes of habitat change from 1987 to 2000 were the creation of forests, dissection of savannas, attrition of wetlands, and creation of croplands. Meanwhile, from 2000 to 2013, there was attrition of forests, as well as attrition of savannas, dissection of wetlands, and aggregation of croplands. In general, from 1987 to 2013, natural habitats regressed and were replaced by croplands; forests, savannas, and wetlands decreased at an average annual percentage 5.74%, 3.94%, and 2.02%, respectively, whereas croplands increased at an average annual rate of 285.39% of their own area. Aggregation, attrition, dissection, and creation were the main habitat change processes identified for the overall period from 1987 to 2013. There was habitat loss in forests and savannas and habitat fragmentation in wetland due to attrition and dissection, respectively. Identifying and understanding habitat change processes would enable the taking of appropriate biodiversity conservation actions.
    Electronic ISSN: 2413-4155
    Topics: Natural Sciences in General
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  • 86
    Publication Date: 2019-04-29
    Description: Aflatoxin contaminated maize is of public health concern in Kenya. Training farmers on good agricultural practice (GAP) has been touted as a mitigative measure. Little is known of the effect of such training on aflatoxin levels in maize grown in Kenya. This study evaluated what effect training farmers on GAP has on aflatoxin levels in maize grown in Kaptumo, Kilibwoni, and Kipkaren divisions in Nandi County, Kenya. Ninety farmers were recruited into farmer field schools and a questionnaire on GAP administered to each farmer. Maize samples were collected from the farmers and analyzed for aflatoxins using competitive enzyme-linked immunosorbent assay (c-ELISA). All farmers weeded their farms before planting, prepared the land, correctly spaced the seedlings, sorted the maize after shelling, cleaned stores before use and knew that aflatoxins were harmful to humans and animals. Eighty-one farmers did early planting, 88/90 did stooking after harvesting, 89/90 applied fertilizer, 89/90 cleared bushes around the stores, 87/90 used wooden pallets to store maize, 89/90 dried maize after harvesting, 83/90 did crop rotation, and 89/90 used clean transport. Moreover, 62/90 had a relative who had died from liver cancer, 13/90 had fed damaged/rotten seeds to animals, and 45/90 had stored harvested seeds on the ground. The mean aflatoxin levels in season 1 were significantly different from season 2 (1.918 ± 1.065; 1.301 ± 1.501). Our findings suggest that some aspects of the training on GAP were better received than others. Training farmers on GAP results in a decrease in aflatoxin levels in maize grown in Nandi County. Farmers in other maize growing areas of Kenya may benefit from similar training on GAP.
    Electronic ISSN: 2413-4155
    Topics: Natural Sciences in General
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  • 87
    Publication Date: 2019-09-20
    Description: Li2TiO3 nanopowders were synthesized by hydrothermal process using anatase TiO2 and LiOHH2O as raw materials. Li2TiO3 crystallizes in the layered monoclinic structure (space group C2/c) with average crystallite size of 34 nm. Morphology, elemental composition and local structure of products were carried out using high-resolution transmission electron microscopy, field-emission scanning electron microscopy, Raman and Fourier transform infrared spectroscopy. Transport properties investigated by d.c. (4-probe measurements) and a.c. (complex impedance spectroscopy) show the activation energy of 0.71 and 0.65 eV, respectively. The ionic transport properties of Li+ ions in nanocrystalline Li2TiO3 characterized by cyclic voltammetry and impedance spectroscopy validate the good electrochemical properties of this anode material for lithium-ion batteries.
    Electronic ISSN: 2413-4155
    Topics: Natural Sciences in General
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  • 88
    Publication Date: 2019-09-20
    Description: This study assessed farmers’ perception of climate change, estimated the determinants of, and evaluated the relationship among adaptation practices using the multivariate probit model. A survey in 300 agricultural households was carried out covering 10 sample districts considering five agro-ecological zones and a vulnerability index. Four adaptation choices (change in planting date, crop variety, crop type and investment in irrigation) were deemed as outcome variables and socioeconomic, demographic, institutional, farm-level and perceptions variables were deployed as explanatory variables. Their marginal effects were determined for three climatic variables—temperature, precipitation and drought. Age, gender and education of head of household, credit access, farm area, rain-fed farming and tenure, are found to be more influential compared to other factors. All four adaptation-options are found to be complimentary to each other. Importantly, the intensity of impact of dependent variables in different models, and for available adaptation-options, are found to be unequal. Therefore, policy options and support facilities should be devised according to climatic variables and adaptation options to achieve superior results.
    Electronic ISSN: 2413-4155
    Topics: Natural Sciences in General
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  • 89
    Publication Date: 2019-03-18
    Description: A portable Fourier Transform Spectrometer (B3M-IR) is built and used to measure atmospheric trace gases in the city of Beijing during Olympic Games in 2008. A short description of the instrument is first provided in this paper. A detailed spectral analysis is then presented. The total columns of ozone (O3), carbon monoxide (CO), methane (CH4) and nitrous oxide (N2O) are retrieved from the ground-based solar absorption spectra recorded by the B3M-IR during the Olympic Games. Lacking validation data, only the retrieved total column of O3 is compared with that retrieved by MAX-DOAS, which is deployed at the same station. The mean difference between the two methods of measurement is 6.5%, demonstrating the performance and reliability of B3M-IR.
    Electronic ISSN: 2413-4155
    Topics: Natural Sciences in General
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  • 90
    Publication Date: 2019-04-16
    Description: As there is lack of understanding about the effect of transitioning between different flooring materials on the gait of older adults, this study investigated the effect of transitioning between a carpeted floor and a vinyl floor on the gait characteristics of older adults. Fourteen older (65 years old and over) and 14 younger (18 to 35 years old) adults walked on different transitional floors by measuring various gait parameters. While the older participants had greater toe clearance than their younger counterparts, the older participants had smaller toe clearance on a carpeted floor than on a vinyl floor, which would increase the probability of a trip-induced fall. Further, the study found the slower transitional acceleration of the whole body COM and the increased friction demand, especially during the toe-off phase, rather than heel contact phase, which will lead to a slip-induced fall on a vinyl floor shortly after transitioning from a carpeted floor to a vinyl floor. Although the increased likelihood of a slip or trip accident was found throughout the changes in gait parameters, the older participants did not perceive of slipping and tripping much. Therefore, older adults are recommended to be made aware of the danger of slipping and tripping while transitioning between different flooring materials.
    Electronic ISSN: 2413-4155
    Topics: Natural Sciences in General
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  • 91
    Publication Date: 2019-10-31
    Description: Many applications in the context of Industry 4.0 require precise localization. However, indoor localization remains an open problem, especially in complex environments such as industrial environments. In recent years, we have seen the emergence of Ultra WideBand (UWB) localization systems. The aim of this article is to evaluate the performance of a UWB system to estimate the position of a person moving in an indoor environment. To do so, we implemented an experimental protocol to evaluate the accuracy of the UWB system both statically and dynamically. The UWB system is compared to a ground truth obtained by a motion capture system with a millimetric accuracy.
    Electronic ISSN: 2413-4155
    Topics: Natural Sciences in General
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  • 92
    Publication Date: 2019-03-06
    Description: This study assessed farmers’ perception of climate change, estimated the determinants of, and evaluated the relationship among adaptation practices using the multivariate probit model. A survey in 300 agricultural households was carried out covering 10 sample districts considering five agro-ecological zones and a vulnerability index. Four adaptation choices (change in planting date, crop variety, crop type and investment in irrigation) were deemed as outcome variables and socioeconomic, demographic, institutional, farm-level and perceptions variables were deployed as explanatory variables. Their marginal effects were determined for three climatic variables—temperature, precipitation and drought. Age, gender and education of head of household, credit access, farm area, rain-fed farming and tenure, are found to be more influential compared to other factors. All four adaptation-options are found to be complimentary to each other. Importantly, the intensity of impact of dependent variables in different models, and for available adaptation-options, are found to be unequal. Therefore, policy options and support facilities should be devised according to climatic variables and adaptation options to achieve superior results.
    Electronic ISSN: 2413-4155
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  • 93
    Publication Date: 2019-06-14
    Description: LC–NMR combines the advantage of the outstanding separation power of liquid chromatography (LC) and the superior structural elucidating capability of nuclear magnetic resonance (NMR). NMR has proved that it is a standout detector for LC by providing maximum structural information about plant originated extracts particularly in its isolating ability of isomeric (same molecular formula) and/or isobaric (same molecular weight) compounds as compared to other detectors. The present review provides an overview of the LC–NMR developmental trends and its application in natural products analysis. The different LC–NMR operational modes are described, as well as how technical improvements assist in establishing this powerful technique as an important analytical tool in the analysis of complex plant-derived compounds. On-flow, stop-flow and loop-storage modes, as well as the new offline mode LC–SPE–NMR and capLC-NMR configurations that avoid the ingestion of expensive deuterated solvents throughout the experiment are mentioned. Utilization of cryogenic probe and microprobe technologies which are the other important promising approaches for guaranteeing the sensitivity issues are also described. Concluding remarks and future outlooks are also discussed.
    Electronic ISSN: 2413-4155
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  • 94
    Publication Date: 2019-04-21
    Description: In Electrified Vehicles, the cost, efficiency, and durability of electrified vehicles are dependent on the energy storage system (ESS) components, configuration and its performance. This paper, pursuing a minimal size tactic, describes a methodology for quantitatively and qualitatively investigating the impacts of a full bandwidth load on the ESS in the HEV. However, the methodology can be extended to other electrified vehicles. The full bandwidth load, up to the operating frequency of the electric motor drive (20 kHz), is empirically measured which includes a frequency range beyond the usually covered frequency range by published standard drive cycles (up to 0.5 Hz). The higher frequency band is shown to be more efficiently covered by a Hybrid Energy Storage System (HESS) which in this paper is defined as combination of a high energy density battery, an Ultra-Capacitor (UC), an electrolytic capacitor, and a film capacitor. In this paper, the harmonic and dc currents and voltages are measured through two precision methods and then the results are used to discuss about overall HEV efficiency and durability. More importantly, the impact of the addition of high-band energy storage devices in reduction of power loss during transient events is disclosed through precision measurement based methodology.
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  • 95
    Publication Date: 2019-02-15
    Description: (1) Background: After the discovery and application of Chlamydomonas reinhardtii channelrhodopsins, the optogenetic toolbox has been greatly expanded with engineered and newly discovered natural channelrhodopsins. However, channelrhodopsins of higher Ca2+ conductance or more specific ion permeability are in demand. (2) Methods: In this study, we mutated the conserved aspartate of the transmembrane helix 4 (TM4) within Chronos and PsChR and compared them with published ChR2 aspartate mutants. (3) Results: We found that the ChR2 D156H mutant (XXM) showed enhanced Na+ and Ca2+ conductance, which was not noticed before, while the D156C mutation (XXL) influenced the Na+ and Ca2+ conductance only slightly. The aspartate to histidine and cysteine mutations of Chronos and PsChR also influenced their photocurrent, ion permeability, kinetics, and light sensitivity. Most interestingly, PsChR D139H showed a much-improved photocurrent, compared to wild type, and even higher Na+ selectivity to H+ than XXM. PsChR D139H also showed a strongly enhanced Ca2+ conductance, more than two-fold that of the CatCh. (4) Conclusions: We found that mutating the aspartate of the TM4 influences the ion selectivity of channelrhodopsins. With the large photocurrent and enhanced Na+ selectivity and Ca2+ conductance, XXM and PsChR D139H are promising powerful optogenetic tools, especially for Ca2+ manipulation.
    Electronic ISSN: 2076-3417
    Topics: Natural Sciences in General
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  • 96
    Publication Date: 2019-05-16
    Description: Mie resonances in high-refractive-index nanoparticles have been known for a long time but only recently have they became actively explored for control of light in nanostructures, ultra-thin optical components, and metasurfaces. Silicon nanoparticles have been widely studied mainly because of well-established fabrication technology, and other high-index materials remain overlooked. Transition metal dichalcogenides, such as tungsten or molybdenum disulfides and diselenides, are known as van der Waals materials because of the type of force holding material layers together. Transition metal dichalcogenides possess large permittivity values in visible and infrared spectral ranges and, being patterned, can support well-defined Mie resonances. In this Communication, we show that a periodic array of tungsten disulfide (WS2) nanoantennae can be considered to be transdimensional lattice and supports different multipole resonances, which can be controlled by the lattice period. We show that lattice resonances are excited in the proximity to Rayleigh anomaly and have different spectral changes in response to variations of one or another orthogonal period. WS2 nanoantennae, their clusters, oligomers, and periodic array have the potential to be used in future nanophotonic devices with efficient light control at the nanoscale.
    Electronic ISSN: 2076-3417
    Topics: Natural Sciences in General
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  • 97
    Publication Date: 2019-05-16
    Description: Intelligent analysis of surveillance videos over networks requires high recognition accuracy by analyzing good-quality videos that however introduce significant bandwidth requirement. Degraded video quality because of high object dynamics under wireless video transmission induces more critical issues to the success of smart video surveillance. In this paper, an object-based source coding method is proposed to preserve constant quality of video streaming over wireless networks. The inverse relationship between video quality and object dynamics (i.e., decreasing video quality due to the occurrence of large and fast-moving objects) is characterized statistically as a linear model. A regression algorithm that uses robust M-estimator statistics is proposed to construct the linear model with respect to different bitrates. The linear model is applied to predict the bitrate increment required to enhance video quality. A simulated wireless environment is set up to verify the proposed method under different wireless situations. Experiments with real surveillance videos of a variety of object dynamics are conducted to evaluate the performance of the method. Experimental results demonstrate significant improvement of streaming videos relative to both visual and quantitative aspects.
    Electronic ISSN: 2076-3417
    Topics: Natural Sciences in General
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  • 98
    Publication Date: 2019-05-16
    Description: The development of an algorithm to automate the process of measuring the magnetic properties of macroscopic objects in motion is an important problem in various industries, especially in ferrous metallurgy and at factories where ferrous scrap is a strategic raw material. The parameter that requires work control is the hidden mass fraction of a non-magnetic substance that is present in the ferromagnetic raw material. The solution to this problem has no prototypes. In our work, a simple measuring device and a mathematical algorithm for calculating the mass fraction of the non-magnetic fraction in a strongly magnetic matrix were developed. The device is an inductance coil, in which the angle of the electromagnet losses is related to the mass of the magnetic material moving the coil. The magnitude of the instantaneous values of the lost angle integral was compared with the result of weighing the object on scales. This allowed us to calculate the proportion of the magnetic and non-magnetic fractions. The use of this prototype is herein illustrated. The experimental results of the determination of the magnetic-fractional composition depending on the mass of scrap metal and its bulk and the magnetic characteristics are presented.
    Electronic ISSN: 2076-3417
    Topics: Natural Sciences in General
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  • 99
    Publication Date: 2019-05-16
    Description: The lattice Boltzmann method (LBM) is an important numerical algorithm for computational fluid dynamics. This study designs a two-layer parallel model for the Sunway TaihuLight supercomputer SW26010 many-core processor, which implements LBM algorithms and performs optimization. Numerical experiments with different problem sizes proved that the proposed model has better parallel performance and scalability than before. In this study, we performed numerical simulations of the flows around the two-dimensional (2D) NACA0012 airfoil, and the results of a series of flows around the different angles of attack were obtained. The results of the pressure coefficient and lift coefficient were in good agreement with those in the literature.
    Electronic ISSN: 2076-3417
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  • 100
    Publication Date: 2019-05-16
    Description: Dental implants designed with platform switching have been used clinically to reduce crestal bone resorption. The aim of this study was to determine the biomechanical effects of loading types, diameter of platform, and implant diameter in bone strain around immediately loaded implants with platform switching concept. Platform-switching features of dental implants with various diameters of implant body and implant platform (named as RP5.0, RP4.3, and NP3.5) were inserted into artificial bone blocks. The initial implant stability was confirmed using a Periotest device before the loading test. Rosette strain gauges were placed on the alveolar region around the implants, and peak values of the bone strain during a 190-N vertical load or 30-degree lateral load were measured by a data acquisition system. The Kruskal-Wallis test and post-hoc pairwise comparisons were performed as statistical analyses. The median Periotest values of the RP5.0, RP4.3, and NP3.5 implants ranged from −6.59 to −7.34. The RP5.0 implant always showed the lowest bone strain around the implant, regardless of whether a vertical or lateral load was applied. Relative to the RP4.3 and NP3.5 implants, the RP4.3 implant produced a higher bone strain (by approximately 8%) under a vertical load but a lower bone strain (by approximately 25%) under a lateral load. This study confirmed that using a wider implant could relieve the bone strain around an immediately loaded implant with platform switching concept especially under lateral loading.
    Electronic ISSN: 2076-3417
    Topics: Natural Sciences in General
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