The 2023 MDPI Annual Report has
been released!
 
17 pages, 507 KiB  
Article
Comparative Analysis of Bilinear Time Series Models with Time-Varying and Symmetric GARCH Coefficients: Estimation and Simulation
by Ma’mon Abu Hammad, Rami Alkhateeb, Nabil Laiche, Adel Ouannas and Shameseddin Alshorm
Symmetry 2024, 16(5), 581; https://doi.org/10.3390/sym16050581 (registering DOI) - 08 May 2024
Abstract
This paper makes a significant contribution by focusing on estimating the coefficients of a sample of non-linear time series, a subject well-established in the statistical literature, using bilinear time series. Specifically, this study delves into a subset of bilinear models where Generalized Autoregressive [...] Read more.
This paper makes a significant contribution by focusing on estimating the coefficients of a sample of non-linear time series, a subject well-established in the statistical literature, using bilinear time series. Specifically, this study delves into a subset of bilinear models where Generalized Autoregressive Conditional Heteroscedastic (GARCH) models serve as the white noise component. The methodology involves applying the Klimko–Nilsen theorem, which plays a crucial role in extracting the asymptotic behavior of the estimators. In this context, the Generalized Autoregressive Conditional Heteroscedastic model of order (1,1) noted that the GARCH (1,1) model is defined as the white noise for the coefficients of the example models. Notably, this GARCH model satisfies the condition of having time-varying coefficients. This study meticulously outlines the essential stationarity conditions required for these models. The estimation of coefficients is accomplished by applying the least squares method. One of the key contributions lies in utilizing the fundamental theorem of Klimko and Nilsen, to prove the asymptotic behavior of the estimators, particularly how they vary with changes in the sample size. This paper illuminates the impact of estimators and their approximations based on varying sample sizes. Extending our study to include the estimation of bilinear models alongside GARCH and GARCH symmetric coefficients adds depth to our analysis and provides valuable insights into modeling financial time series data. Furthermore, this study sheds light on the influence of the GARCH white noise trace on the estimation of model coefficients. The results establish a clear connection between the model characteristics and the nature of the white noise, contributing to a more profound understanding of the relationship between these elements. Full article
(This article belongs to the Special Issue Advance in Functional Equations, Second Edition)
Show Figures

Figure 1

42 pages, 2347 KiB  
Review
Recent Advances in the Discovery of SIRT1/2 Inhibitors via Computational Methods: A Perspective
by Naomi Scarano, Chiara Brullo, Francesca Musumeci, Enrico Millo, Santina Bruzzone, Silvia Schenone and Elena Cichero
Pharmaceuticals 2024, 17(5), 601; https://doi.org/10.3390/ph17050601 (registering DOI) - 08 May 2024
Abstract
Sirtuins (SIRTs) are classified as class III histone deacetylases (HDACs), a family of enzymes that catalyze the removal of acetyl groups from the ε-N-acetyl lysine residues of histone proteins, thus counteracting the activity performed by histone acetyltransferares (HATs). Based on their involvement in [...] Read more.
Sirtuins (SIRTs) are classified as class III histone deacetylases (HDACs), a family of enzymes that catalyze the removal of acetyl groups from the ε-N-acetyl lysine residues of histone proteins, thus counteracting the activity performed by histone acetyltransferares (HATs). Based on their involvement in different biological pathways, ranging from transcription to metabolism and genome stability, SIRT dysregulation was investigated in many diseases, such as cancer, neurodegenerative disorders, diabetes, and cardiovascular and autoimmune diseases. The elucidation of a consistent number of SIRT–ligand complexes helped to steer the identification of novel and more selective modulators. Due to the high diversity and quantity of the structural data thus far available, we reviewed some of the different ligands and structure-based methods that have recently been used to identify new promising SIRT1/2 modulators. The present review is structured into two sections: the first includes a comprehensive perspective of the successful computational approaches related to the discovery of SIRT1/2 inhibitors (SIRTIs); the second section deals with the most interesting SIRTIs that have recently appeared in the literature (from 2017). The data reported here are collected from different databases (SciFinder, Web of Science, Scopus, Google Scholar, and PubMed) using “SIRT”, “sirtuin”, and “sirtuin inhibitors” as keywords. Full article
(This article belongs to the Special Issue Computer-Aided Drug Design and Drug Discovery)
28 pages, 2134 KiB  
Article
Examining the Influence of Secondary Math and Science Teacher Preparation Programs on Graduates’ Instructional Quality and Persistence in Teaching
by Danielle Marie Rhemer, Will Rogers and Sherry Ann Southerland
Educ. Sci. 2024, 14(5), 506; https://doi.org/10.3390/educsci14050506 (registering DOI) - 08 May 2024
Abstract
This quantitative, non-experimental study explored the relationship between the features of math and science teachers’ preparation programs and their graduates’ instructional rigor and persistence in teaching. Five math and science teacher preparation programs from across the United States were examined. Six sets of [...] Read more.
This quantitative, non-experimental study explored the relationship between the features of math and science teachers’ preparation programs and their graduates’ instructional rigor and persistence in teaching. Five math and science teacher preparation programs from across the United States were examined. Six sets of instructional tasks were collected from forty-six recent graduates of these programs to provide insights into novices’ instructional rigor, and employment data were collected for thirty-seven of these graduates three to eight years after graduation. Regardless of the program’s features, all teachers could design and implement instruction with moderate to high rigor. However, this ability was not the norm. Mixed-effect models suggest the strongest evidence between degree types (bachelor versus post-bachelor) was related to teachers’ persistence: novices from graduate programs were more likely to persist in the work. However, no program feature was strongly associated with instructional rigor. Further research is needed to determine if the differences we found in teacher persistence are due to the nature of applicants drawn to particular programs (undergraduate versus graduate) or the program’s structure. Future research is also needed to explore the influence of instructional context (i.e., district, school, and department norms for instruction) on math and science teachers’ instructional rigor. Full article
Show Figures

Figure 1

10 pages, 2342 KiB  
Article
Preparation of Single-Helical Curdlan Hydrogel and Its Activation with Coagulation Factor G
by Geying Ru, Xiaoshuang Yan, Huijuan Wang and Jiwen Feng
Polymers 2024, 16(10), 1323; https://doi.org/10.3390/polym16101323 (registering DOI) - 08 May 2024
Abstract
β-1,3-glucans are a kind of natural polysaccharide with immunomodulatory, antitumor, and anti-inflammatory properties. Curdlan, as the simplest linear β-1,3-glucan, possesses a variety of biological activities and thermogelation properties. However, due to the complexity and variability of the conformations of curdlan, the exact structure–activity [...] Read more.
β-1,3-glucans are a kind of natural polysaccharide with immunomodulatory, antitumor, and anti-inflammatory properties. Curdlan, as the simplest linear β-1,3-glucan, possesses a variety of biological activities and thermogelation properties. However, due to the complexity and variability of the conformations of curdlan, the exact structure–activity relationship remains unclear. We prepare a chemically crosslinked curdlan hydrogel with the unique single-helical skeleton (named S gel) in 0.4 wt% NaOH at 40 °C, confirmed by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). X-ray diffractometry (XRD) data show that S gel maintains the single-helical crystal structure, and the degree of crystallinity of the S gel is ~24%, which is slightly lower than that of the raw powder (~31%). Scanning electron microscopy (SEM) reveals that S gel has a continuous network structure, with large pores measuring 50–200 μm, which is consistent with its high swelling property. Using the 13C high-resolution magic angle spinning nuclear magnetic resonance (HRMAS NMR) method, we determine that most of the single-helical skeleton carbon signals in the swollen S gel are visible, suggesting that the single-helical skeleton of S gel exhibits fascinating mobility at room temperature. Finally, we reveal that the binding of S gel to coagulation Factor G from tachypleus amebocyte lysate increases and saturates at 20 μL tachypleus amebocyte lysate per mg of S gel. Our prepared S gel can avoid the transformation of curdlan conformations and retain the bioactivity of binding to coagulation Factor G, making it a valuable material for use in the food industry and the pharmaceutical field. This work deepens the understanding of the relationship between the single-helical structure and the activity of curdlan, promoting the development and application of β-1,3-glucans. Full article
(This article belongs to the Special Issue Biopolymer-Based Materials in Medical Applications)
Show Figures

Figure 1

17 pages, 1030 KiB  
Article
Entropy-Aided Meshing-Order Modulation Analysis for Wind Turbine Planetary Gear Weak Fault Detection under Variable Rotational Speed
by Shaodan Zhi, Hengshan Wu, Haikuo Shen, Tianyang Wang and Hongfei Fu
Entropy 2024, 26(5), 409; https://doi.org/10.3390/e26050409 (registering DOI) - 08 May 2024
Abstract
As one of the most vital energy conversation systems, the safe operation of wind turbines is very important; however, weak fault and time-varying speed may challenge the conventional monitoring strategies. Thus, an entropy-aided meshing-order modulation method is proposed for detecting the optimal frequency [...] Read more.
As one of the most vital energy conversation systems, the safe operation of wind turbines is very important; however, weak fault and time-varying speed may challenge the conventional monitoring strategies. Thus, an entropy-aided meshing-order modulation method is proposed for detecting the optimal frequency band, which contains the weak fault-related information. Specifically, the variable rotational frequency trend is first identified and extracted based on the time–frequency representation of the raw signal by constructing a novel scaling-basis local reassigning chirplet transform (SLRCT). A new entropy-aided meshing-order modulation (EMOM) indicator is then constructed to locate the most sensitive modulation frequency area according to the extracted fine speed trend with the help of order tracking technique. Finally, the raw vibration signal is bandpass filtered via the corresponding optimal frequency band with the highest EMOM indicator. The order components resulting from the weak fault can be highlighted to accomplish weak fault detection. The effectiveness of the proposed EMOM analysis-based method has been tested using the experimental data of three different gear fault types of different fault levels from a planetary test rig. Full article
10 pages, 486 KiB  
Article
Histological Changes in the Popliteal Artery Wall in Patients with Critical Limb Ischemia
by Octavian Andercou, Maria Cristina Andrei, Dan Gheban, Dorin Marian, Horațiu F. Coman, Valentin Aron Oprea, Florin Vasile Mihaileanu, Razvan Ciocan, Beatrix Cucuruz and Bogdan Stancu
Diagnostics 2024, 14(10), 989; https://doi.org/10.3390/diagnostics14100989 (registering DOI) - 08 May 2024
Abstract
Introduction: This prospective study aims to illustrate the histopathological arterial changes in the popliteal artery in peripheral arterial disease of the lower limbs. Material and method: A total of 60 popliteal artery segments taken from patients who had undergone lower limb amputation were [...] Read more.
Introduction: This prospective study aims to illustrate the histopathological arterial changes in the popliteal artery in peripheral arterial disease of the lower limbs. Material and method: A total of 60 popliteal artery segments taken from patients who had undergone lower limb amputation were examined between April and June 2023. The degree of arterial stenosis, medial calcinosis, and the vasa vasorum changes in the arterial adventitia were quantified. The presence of risk factors for atherosclerosis was also observed. Results: Atherosclerotic plaque was found in all of the examined segments. Medial calcinosis was observed in 40 (66.6%) of the arterial segments. A positive association between the degree of arterial stenosis and the vasa vasorum changes in the arterial adventitia was also found (p = 0.025). The level of blood sugar and cholesterol were predictive factors for the severity of atherosclerosis. Conclusions: Atherosclerosis and medial calcinosis are significant in patients who underwent lower limb amputation. Medial calcinosis causes damage to the arterial wall and leads to a reduction in responsiveness to dilator stimuli. Full article
(This article belongs to the Special Issue Cardiovascular Diseases: Diagnosis and Management)
11 pages, 1039 KiB  
Article
Serum Amyloid A3 Promoter-Luciferase Reporter Mice Are Useful for Early Drug-Induced Nephrotoxicity Detection
by Ayane Kudo, Haruka Osedo, Rahmawati Aisyah, Nao Yazawa, Tolulope Peter Saliu, Kenshu Miyata, Thanutchaporn Kumrungsee and Noriyuki Yanaka
Int. J. Mol. Sci. 2024, 25(10), 5124; https://doi.org/10.3390/ijms25105124 (registering DOI) - 08 May 2024
Abstract
Early detection of drug-induced kidney injury is essential for drug development. In this study, multiple low-dose aristolochic acid (AA) and cisplatin (Cis) injections increased renal mRNA levels of inflammation, fibrosis, and renal tubule injury markers. We applied a serum amyloid A3 (Saa3) promoter-driven [...] Read more.
Early detection of drug-induced kidney injury is essential for drug development. In this study, multiple low-dose aristolochic acid (AA) and cisplatin (Cis) injections increased renal mRNA levels of inflammation, fibrosis, and renal tubule injury markers. We applied a serum amyloid A3 (Saa3) promoter-driven luciferase reporter (Saa3 promoter-luc mice) to these two tubulointerstitial nephritis models and performed in vivo bioluminescence imaging to monitor early renal pathologies. The bioluminescent signals from renal tissues with AA or CIS injections were stronger than those from normal kidney tissues obtained from normal mice. To verify whether the visualized bioluminescence signal was specifically generated by the injured kidney, we performed in vivo bioluminescence analysis after opening the stomachs of Saa3 promoter-luc mice, and the Saa3-mediated bioluminescent signal was specifically detected in the injured kidney. This study showed that Saa3 promoter activity is a potent non-invasive indicator for the early detection of drug-induced nephrotoxicity. Full article
(This article belongs to the Special Issue Advances in Luciferase)
19 pages, 634 KiB  
Article
Mathematical Model of the Process of Data Transmission over the Radio Channel of Cyber-Physical Systems
by Fazliddin Makhmudov, Andrey Privalov, Alexander Privalov, Elena Kazakevich, Gamzatdin Bekbaev, Alexey Boldinov, Kyung Hoon Kim and Young Im-Cho
Mathematics 2024, 12(10), 1452; https://doi.org/10.3390/math12101452 (registering DOI) - 08 May 2024
Abstract
This article introduces a refined mathematical model to evaluate the quality of mobile radio channels within cyber-physical systems, employing the topological transformation of stochastic networks. The operation of the radio channel is conceptualized as a stochastic network, enabling the derivation of critical metrics [...] Read more.
This article introduces a refined mathematical model to evaluate the quality of mobile radio channels within cyber-physical systems, employing the topological transformation of stochastic networks. The operation of the radio channel is conceptualized as a stochastic network, enabling the derivation of critical metrics such as an equivalent function, mathematical expectation, variance, and the time distribution function of the implemented processes. The model uses the Gamma distribution for the initial distribution functions of random variables, enhancing its analytical precision. A significant advancement of this study is the development of a comprehensive model that describes the data transmission process through phases of connection establishment, information transmission, and connection maintenance. The innovative aspect of this research lies in applying an equivalent function to a stochastic network that includes a logical “AND” node with gamma-distributed incoming branches. The stochastic network presented in the article, which includes a logical “AND” node, helps to elucidate the mechanism for obtaining an equivalent function for such networks, allowing the application area of the GERT method to be expanded. This methodological enhancement extends the previously limited scope of topological transformation methods, which only applied to exponential distribution models for the timing of branch inputs. By integrating a Gamma distribution, the model simplifies the equivalent function and reduces the computational complexity required to assess the radio channel’s quality, ensuring the accuracy needed for engineering calculations. Moreover, the proposed method requires 25–40% fewer series members than the traditional Taylor series decomposition, while maintaining comparable computational complexity for the typical series members. Furthermore, the maximum absolute error in the calculations is capped at 9 × 103, which is well within acceptable limits for engineering purposes. Primarily designed for radio channels in cyber-physical systems, the model’s applicability extends to wireless communications, providing a valuable tool for evaluating channel efficiency and security in the face of increasing cyber threats. Full article
22 pages, 19008 KiB  
Article
Curcumin Improves Neurogenesis in Alzheimer’s Disease Mice via the Upregulation of Wnt/β-Catenin and BDNF
by Shengchun Lou, Danfeng Gong, Mengting Yang, Qing Qiu, Jialie Luo and Tingting Chen
Int. J. Mol. Sci. 2024, 25(10), 5123; https://doi.org/10.3390/ijms25105123 (registering DOI) - 08 May 2024
Abstract
Adult neurogenesis in the dentate gyrus (DG) is impaired during Alzheimer’s disease (AD) progression. Curcumin has been reported to reduce cell apoptosis and stimulate neurogenesis. This study aimed to investigate the influence of curcumin on adult neurogenesis in AD mice and its potential [...] Read more.
Adult neurogenesis in the dentate gyrus (DG) is impaired during Alzheimer’s disease (AD) progression. Curcumin has been reported to reduce cell apoptosis and stimulate neurogenesis. This study aimed to investigate the influence of curcumin on adult neurogenesis in AD mice and its potential mechanism. Two-month-old male C57BL/6J mice were injected with soluble β-amyloid (Aβ1–42) using lateral ventricle stereolocalization to establish AD models. An immunofluorescence assay, including bromodeoxyuridine (BrdU), doublecortin (DCX), and neuron-specific nuclear antigen (NeuN), was used to detect hippocampal neurogenesis. Western blot and an enzyme-linked immunosorbent assay (ELISA) were used to test the expression of related proteins and the secretion of brain-derived neurotrophic factor (BDNF). A Morris water maze was used to detect the cognitive function of the mice. Our results showed that curcumin administration (100 mg/kg) rescued the impaired neurogenesis of Aβ1–42 mice, shown as enhanced BrdU+/DCX+ and BrdU+/NeuN+ cells in DG. In addition, curcumin regulated the phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt) -mediated glycogen synthase kinase-3β (GSK3β) /Wingless/Integrated (Wnt)/β-catenin pathway and cyclic adenosine monophosphate response element-binding protein (CREB)/BDNF in Aβ1–42 mice. Inhibiting Wnt/β-catenin and depriving BDNF could reverse both the upregulated neurogenesis and cognitive function of curcumin-treated Aβ1–42 mice. In conclusion, our study indicates that curcumin, through targeting PI3K/Akt, regulates GSK3β/Wnt/β-catenin and CREB/BDNF pathways, improving the adult neurogenesis of AD mice. Full article
(This article belongs to the Section Molecular Pharmacology)
Show Figures

Figure 1

17 pages, 1783 KiB  
Article
Dry and Wet Spells in Poland in the Period 1966–2023
by Joanna Wibig
Water 2024, 16(10), 1344; https://doi.org/10.3390/w16101344 (registering DOI) - 08 May 2024
Abstract
The aim of this study is to present the spatial and temporal variability of the frequency of dry and wet days and dry and wet spells against the background of changes in precipitation and atmospheric circulation. The study is based on daily precipitation [...] Read more.
The aim of this study is to present the spatial and temporal variability of the frequency of dry and wet days and dry and wet spells against the background of changes in precipitation and atmospheric circulation. The study is based on daily precipitation totals from 46 meteorological stations in Poland from 1966 to 2023. Additionally, seven circulation indices were used, namely GBI, NAO, AO, EA, EA/WR, SCAND, and AMO. Dry days are defined as days without precipitation. Wet days are days with at least 1 mm of precipitation. It was shown that dry spells are much more common than wet spells, are longer, and cover larger areas. Long-term changes in the annual characteristics of dry and wet days and spells are not statistically significant. Only the length of the most extended dry spell in the year increases. However, there are significant changes in their annual cycles. Spring is drier; in summer, precipitation decreases in the south and increases in the north; November and December, symbols of gloomy rainy weather, are increasingly drier; and rainy weather has shifted to January and February. The impact of circulation varies according to the season, with the NAO, AO, SCAND, and GBI indices having the greatest influence. Full article
11 pages, 436 KiB  
Article
Resilience, Burnout and Mental Health in Nurses: A Latent Mediation Model
by Iván Suazo Galdames, María del Mar Molero Jurado, Elena Fernández Martínez, María del Carmen Pérez-Fuentes and José Jesús Gázquez Linares
J. Clin. Med. 2024, 13(10), 2769; https://doi.org/10.3390/jcm13102769 (registering DOI) - 08 May 2024
Abstract
Background/Objectives: The burnout syndrome in nurses has been related to the development of mental health problems. On the contrary, resilience is related to adequately coping with stressful situations and better mental health. The objective was to analyze the relationship between resilience and [...] Read more.
Background/Objectives: The burnout syndrome in nurses has been related to the development of mental health problems. On the contrary, resilience is related to adequately coping with stressful situations and better mental health. The objective was to analyze the relationship between resilience and mental health problems in nurses and estimate the proportion mediated by burnout in the association. Methods: In 2021, a total of 1165 Spanish nurses were selected through a stratified random sampling method. Participants anonymously filled in the Resilience Scale (RS-14), the Maslach Burnout Inventory Survey, and the General Health Questionnaire. To test the hypothesis proposed and explain the mediating effect of burnout empirically, structural equation modeling (SEM) was applied. A latent mediation model was computed. Results: Resilience was negatively related to burnout and mental health problems. The direct relationship between burnout and the latent health variable was positive. In addition, in view of the total effect of resilience on mental health problems and the magnitude of the indirect effect, we stated that the proportion of this effect mediated by burnout ranged from 0.486 to 0.870. Conclusions: This study reveals that fostering resilience in nurses directly and indirectly reduces burnout and improves their mental health. The implementation of resilience programs and supportive institutional policies is recommended to improve working conditions and the quality of patient care. Full article
(This article belongs to the Section Mental Health)
17 pages, 8061 KiB  
Article
Integrated LSPR Biosensing Signal Processing Strategy and Visualization Implementation
by Mixing Zhou and Zhaoxin Geng
Micromachines 2024, 15(5), 631; https://doi.org/10.3390/mi15050631 (registering DOI) - 08 May 2024
Abstract
The LSPR biosensor chip is a groundbreaking tool popular in laboratory settings for identifying disease markers. However, its use in clinical environments is not as widespread. One notable gap is the lack of a universal signal processing tool for LSPR biosensing. To escalate [...] Read more.
The LSPR biosensor chip is a groundbreaking tool popular in laboratory settings for identifying disease markers. However, its use in clinical environments is not as widespread. One notable gap is the lack of a universal signal processing tool for LSPR biosensing. To escalate its precision, there is an emerging need for software that not only optimizes signal processing but also incorporates self-verification functionalities within LSPR biochemical sensors. Enter the visual LSPR sensor software—an innovative platform that processes real-time transmission or reflection spectra. This advanced software adeptly captures the nuanced structural changes at the nanostructure interface prompted by environmental fluctuations. It diligently records and computes a suite of parameters, including the resonance wavelength shift, full width at half maximum, sensitivity, and quality factor. These features empower users to tailor processing algorithms for each data capture session. Transcending traditional instruments, this method accommodates a multitude of parameters and ensures robust result validation while tactfully navigating nanostructure morphology complexities. Forsaking third-party tool dependencies, the software tackles challenges of precision and cost-effectiveness head-on, heralding a significant leap forward in nanophotonics, especially for high-throughput LSPR biosensing applications. This user-centric innovation marks substantial progress in biochemical detection. It is designed to serve both researchers and practitioners in the field of nanophotonic sensing technology, simplifying complexity while enhancing reliability and efficiency. Full article
18 pages, 453 KiB  
Article
On Uniformly Starlike Functions with Respect to Symmetrical Points Involving the Mittag-Leffler Function and the Lambert Series
by Jamal Salah
Symmetry 2024, 16(5), 580; https://doi.org/10.3390/sym16050580 (registering DOI) - 08 May 2024
Abstract
The aim of this paper is to define the linear operator based on the generalized Mittag-Leffler function and the Lambert series. By using this operator, we introduce a new subclass of β-uniformly starlike functions ΤJ(αi). Further, we obtain coefficient estimates, convex linear combinations, [...] Read more.
The aim of this paper is to define the linear operator based on the generalized Mittag-Leffler function and the Lambert series. By using this operator, we introduce a new subclass of β-uniformly starlike functions ΤJ(αi). Further, we obtain coefficient estimates, convex linear combinations, and radii of close-to-convexity, starlikeness, and convexity for functions f∈ΤJ(αi). In addition, we investigate the inclusion conditions of the Hadamard product and the integral transform. Finally, we determine the second Hankel inequality for functions belonging to this subclass. Full article
(This article belongs to the Special Issue Symmetry in Geometric Theory of Analytic Functions)
19 pages, 522 KiB  
Article
The Carbon Emission Reduction Effects of the Quality and Quantity of R&D Activities: Evidence from Chinese Provinces
by Aimin Li and Qiang Hu
Sustainability 2024, 16(10), 3942; https://doi.org/10.3390/su16103942 (registering DOI) - 08 May 2024
Abstract
Research and Development (R&D) have significant impacts on carbon emissions, yet the specific data on R&D capital stock and carbon emissions have not been released by Chinese officials, hindering in-depth analysis. In light of this, this study calculates the R&D capital stock of [...] Read more.
Research and Development (R&D) have significant impacts on carbon emissions, yet the specific data on R&D capital stock and carbon emissions have not been released by Chinese officials, hindering in-depth analysis. In light of this, this study calculates the R&D capital stock of Chinese provinces based on the SNA2008 framework and the BEA method, and estimates the carbon emissions from energy consumption and cement production using the carbon emission factor method. It then examines the carbon emission reduction effects of the quality and quantity of R&D activities at the provincial level. We find that the quality of R&D activities has a significant carbon emission reduction effect, which is stronger in regions with high levels of economic growth and marketization, and this effect strengthens over time. Moreover, mechanism analysis shows that both the quality and quantity of R&D activities reduce carbon emissions by promoting industrial structure upgrading. This paper expands the analytical approach and framework for the carbon reduction effects of R&D activities and offers significant policy and practical implications. Full article
18 pages, 1306 KiB  
Review
Bridging the Gap: Harnessing Plant Bioactive Molecules to Target Gut Microbiome Dysfunctions in Amyotrophic Lateral Sclerosis
by Mirela Pribac, Anca Motataianu, Sebastian Andone, Elena Mardale and Sebastian Nemeth
Curr. Issues Mol. Biol. 2024, 46(5), 4471-4488; https://doi.org/10.3390/cimb46050271 (registering DOI) - 08 May 2024
Abstract
The correlation between neurodegenerative diseases and the gut microbiome is increasingly evident, with amyotrophic lateral sclerosis (ALS) being particularly notable for its severity and lack of therapeutic options. The gut microbiota, implicated in the pathogenesis and development of ALS, plays a crucial role [...] Read more.
The correlation between neurodegenerative diseases and the gut microbiome is increasingly evident, with amyotrophic lateral sclerosis (ALS) being particularly notable for its severity and lack of therapeutic options. The gut microbiota, implicated in the pathogenesis and development of ALS, plays a crucial role in the disease. Bioactive plant molecules, specifically volatile compounds in essential oils, offer a promising therapeutic avenue due to their anti-inflammatory properties and gut-modulating effects. Our narrative review aimed to identify microbiota-associated bacteria in ALS and analyze the benefits of administering bioactive plant molecules as much-needed therapeutic options in the management of this disease. A comprehensive search of PubMed database articles published before December 2023, encompassing research on cell, human, and animal ALS models, was conducted. After selecting, analyzing, and discussing key articles, bacteria linked to ALS pathogenesis and physiopathology were identified. Notably, positively highlighted bacteria included Akkermansia muciniphila (Verrucomicrobia phylum), Faecalibacterium prausnitzii, and Butyrivibrio spp. (Firmicutes phylum). Conversely, members of the Escherichia coli spp. (Proteobacteria phylum) and Ruminococcus spp. (Firmicutes phylum) stood out negatively in respect to ALS development. These bacteria were associated with molecular changes linked to ALS pathogenesis and evolution. Bioactive plant molecules can be directly associated with improvements in the microbiome, due to their role in reducing inflammation and oxidative stress, emerging as one of the most promising natural agents for enriching present-day ALS treatments. Full article
(This article belongs to the Special Issue Aging and Oxidative Stress in Nervous System)
Show Figures

Figure 1

23 pages, 1948 KiB  
Article
Shape Matters: Impact of Mesoporous Silica Nanoparticle Morphology on Anti-Tumor Efficacy
by Weixiang Fang, Kailing Yu, Songhan Zhang, Lai Jiang, Hongyue Zheng, Qiaoling Huang and Fanzhu Li
Pharmaceutics 2024, 16(5), 632; https://doi.org/10.3390/pharmaceutics16050632 (registering DOI) - 08 May 2024
Abstract
A nanoparticle’s shape is a critical determinant of its biological interactions and therapeutic effectiveness. This study investigates the influence of shape on the performance of mesoporous silica nanoparticles (MSNs) in anticancer therapy. MSNs with spherical, rod-like, and hexagonal-plate-like shapes were synthesized, with particle [...] Read more.
A nanoparticle’s shape is a critical determinant of its biological interactions and therapeutic effectiveness. This study investigates the influence of shape on the performance of mesoporous silica nanoparticles (MSNs) in anticancer therapy. MSNs with spherical, rod-like, and hexagonal-plate-like shapes were synthesized, with particle sizes of around 240 nm, and their other surface properties were characterized. The drug loading capacities of the three shapes were controlled to be 47.46%, 49.41%, and 46.65%, respectively. The effects of shape on the release behaviors, cellular uptake mechanisms, and pharmacological behaviors of MSNs were systematically investigated. Through a series of in vitro studies using 4T1 cells and in vivo evaluations in 4T1 tumor-bearing mice, the release kinetics, cellular behaviors, pharmacological effects, circulation profiles, and therapeutic efficacy of MSNs were comprehensively assessed. Notably, hexagonal-plate-shaped MSNs loaded with PTX exhibited a prolonged circulation time (t1/2 = 13.59 ± 0.96 h), which was approximately 1.3 times that of spherical MSNs (t1/2 = 10.16 ± 0.38 h) and 1.5 times that of rod-shaped MSNs (t1/2 = 8.76 ± 1.37 h). This research underscores the significance of nanoparticles’ shapes in dictating their biological interactions and therapeutic outcomes, providing valuable insights for the rational design of targeted drug delivery systems in cancer therapy. Full article
(This article belongs to the Special Issue Smart Nanotechnology to Enhancing Drug Delivery and Bioavailability)
14 pages, 1066 KiB  
Article
Bioavailability of Lutein from Marigold Flowers (Free vs. Ester Forms): A Randomised Cross-Over Study to Assess Serum Response and Visual Contrast Threshold in Adults
by Begoña Olmedilla-Alonso, Fernando Granado-Lorencio, Julio Castro-Feito, Carmen Herrero-Barbudo, Inmaculada Blanco-Navarro and Rocío Estévez-Santiago
Nutrients 2024, 16(10), 1415; https://doi.org/10.3390/nu16101415 (registering DOI) - 08 May 2024
Abstract
Lutein (Lut) and zeaxanthin (Zeax) are found in the blood and are deposited in the retina (macular pigment). Both are found in the diet in free form and esterified with fatty acids. A high intake and/or status is associated with a lower risk [...] Read more.
Lutein (Lut) and zeaxanthin (Zeax) are found in the blood and are deposited in the retina (macular pigment). Both are found in the diet in free form and esterified with fatty acids. A high intake and/or status is associated with a lower risk of chronic diseases, especially eye diseases. There is a large global demand for Lut in the dietary supplement market, with marigold flowers being the main source, mainly as lutein esters. As the bioavailability of Lut from free or ester forms is controversial, our aim was to assess the bioavailability of Lut (free vs. ester) and visual contrast threshold (CT). Twenty-four healthy subjects (twelve women, twelve men), aged 20–35 and 50–65 years, were enrolled in a cross-sectional study to consume 6 mg lutein/day from marigold extract (free vs. ester) for two months. Blood samples were taken at baseline and after 15, 40, and 60 days in each period. Serum Lut and Zeax were analysed using HPLC, and dietary intake was determined with a 7-day food record at the beginning of each period. CT, with and without glare, was at 0 and 60 days at three levels of visual angle. Lut + Zeax intake at baseline was 1.9 mg/day, and serum lutein was 0.36 µmol/L. Serum lutein increased 2.4-fold on day 15 (up to 0.81 and 0.90 µmol/L with free and ester lutein, respectively) and was maintained until the end of the study. Serum Zeax increased 1.7-fold. There were no differences in serum Lut responses to free or ester lutein at any time point. CT responses to lutein supplementation (free vs. ester) were not different at any time point. CT correlated with Lut under glare conditions, and better correlations were obtained at low frequencies in the whole group due to the older group. The highest correlations occurred between CT at high frequency and with glare with serum Lut and Lut + Zeax. Only in the older group were inverse correlations found at baseline at a high frequency with L + Z and with Lut/cholesterol and at a low frequency with Lut/cholesterol. In conclusion, daily supplementation with Lut for 15 days significantly increases serum Lut in normolipemic adults to levels associated with a reduced risk of age-related eye disease regardless of the chemical form of lutein supplied. Longer supplementation, up to two months, does not significantly alter the concentration achieved but may contribute to an increase in macular pigment (a long-term marker of lutein status) and thus improve the effect on visual outcomes. Full article
(This article belongs to the Special Issue Dietary Supplements in Human Health and Disease)
Show Figures

Figure 1

19 pages, 446 KiB  
Article
Bioactivity Profiling of Daedaleopsis confragosa (Bolton) J. Schröt. 1888: Implications for Its Possible Application in Enhancing Women’s Reproductive Health
by Djordje Ilić, Maja Karaman, Mirjana Bogavac, Jovana Mišković and Milena Rašeta
Pharmaceuticals 2024, 17(5), 600; https://doi.org/10.3390/ph17050600 (registering DOI) - 08 May 2024
Abstract
This study investigates the bioactivity profile of wood-rotting fungal species Daedaleopsis confragosa (Bolton) J. Schröt. 1888, focusing on its antioxidant, cytotoxic, and genotoxic activities and enzyme modulation properties with respect to its possible application in terms of enhancing women’s reproductive health. Two types [...] Read more.
This study investigates the bioactivity profile of wood-rotting fungal species Daedaleopsis confragosa (Bolton) J. Schröt. 1888, focusing on its antioxidant, cytotoxic, and genotoxic activities and enzyme modulation properties with respect to its possible application in terms of enhancing women’s reproductive health. Two types of extracts, including those based on EtOH extraction (DC) and hydrodistillation (DCHD), were investigated. The results indicate that the radical scavenging capacity against the DPPH radical and reduction potential were stronger in the DC extracts owing to the higher total phenolic content (TPC) and total flavonoid content (TFC) (25.30 ± 1.05 mg GAE/g d.w. and 2.84 ± 0.85 mg QE/g d.w., respectively). The same trend was observed in the protein phosphatase-1 (PP1) activity and in the genotoxic activity against the δ virus since only the DC extract exhibited DNA disintegration regarding a dilution of 1:100. Conversely, the DCHD extract exhibited increased hemolytic and cytotoxic effects (339.39% and IC50 = 27.76 ± 0.89 μg/mL—72 h incubation, respectively), along with greater inhibition of the AChE enzyme (IC50 = 3.11 ± 0.45 mg/mL) and hemolytic activity. These results suggest that terpenoids and steroids may be responsible for the observed activity in DCHD as these compounds could potentially be extracted following the HD procedure. This comprehensive bioactivity profiling offers valuable insights into the potential therapeutic applications of D. confragosa from Serbia and underscores the importance of further investigations for harnessing its pharmacological potential. Full article
23 pages, 692 KiB  
Article
Optimization of Energy Efficiency for Federated Learning over Unmanned Aerial Vehicle Communication Networks
by Xuan-Toan Dang and Oh-Soon Shin
Electronics 2024, 13(10), 1827; https://doi.org/10.3390/electronics13101827 (registering DOI) - 08 May 2024
Abstract
Federated learning (FL) is considered a promising machine learning technique that has attracted increasing attention in recent years. Instead of centralizing data in one location for training a global model, FL allows the model training to occur on user devices, such as smartphones, [...] Read more.
Federated learning (FL) is considered a promising machine learning technique that has attracted increasing attention in recent years. Instead of centralizing data in one location for training a global model, FL allows the model training to occur on user devices, such as smartphones, IoT devices, or local servers, thereby respecting data privacy and security. However, implementing FL in wireless communication faces a significant challenge due to the inherent unpredictability and constant fluctuations in channel characteristics. A key challenge in implementing FL over wireless communication lies in optimizing energy efficiency. This holds significant importance, especially considering user devices with restricted power resources. On the other hand, unmanned aerial vehicle (UAV) technologies present a cost-effective solution owing to flexibility and mobility compared to terrestrial base stations. Consequently, the deployment of UAV communication in FL is viewed as a potential approach to deal with the energy efficiency challenge. In this paper, we address the problem of minimizing the total energy consumption of all user equipment (UE) during the training phase of FL over a UAV communication network. Our proposed system facilitates UE to operate concurrently at the same time and frequency, thereby improving bandwidth utilization efficiently. In this paper, we address the problem of minimizing the total energy consumption during the training phase of FL over a UAV communication network. To deal with the proposed nonconvex problem, we propose a novel alternating optimization approach by dividing the problem into two suboptimal problems. We then develop iterative algorithms based on the inner approximation method, yielding at least one locally optimal solution. The numerical results demonstrate the superiority of the proposed algorithm in solving the proposed problem compared to other benchmark algorithms, particularly in determining the optimal trajectory of the UAVs. In addition, we conduct extensive experiments to evaluate how different parameter settings affect performance after implementing the proposed optimization approaches for deploying FL within the UAV communication system. These analyses yield valuable insights into the comparative effectiveness of the proposed optimization algorithms concerning overall energy consumption reduction. Full article
(This article belongs to the Special Issue Sixth-Generation Wireless Communications: Theory and Applications)
11 pages, 800 KiB  
Article
Haematochemical Profile of Healthy Dogs Seropositive for Single or Multiple Vector-Borne Pathogens
by Raffaella Cocco, Sara Sechi, Maria Rizzo, Andrea Bonomo, Francesca Arfuso and Elisabetta Giudice
Vet. Sci. 2024, 11(5), 205; https://doi.org/10.3390/vetsci11050205 (registering DOI) - 08 May 2024
Abstract
Background: the present study aimed to investigate the immunological response to common vector-borne pathogens and to evaluate their impact on haematochemical parameters in owned dogs. Methods: Blood samples were collected from 400 clinically healthy dogs living in an endemic area (Sardinia Island, Italy). [...] Read more.
Background: the present study aimed to investigate the immunological response to common vector-borne pathogens and to evaluate their impact on haematochemical parameters in owned dogs. Methods: Blood samples were collected from 400 clinically healthy dogs living in an endemic area (Sardinia Island, Italy). All dogs were serologically tested for VBDs and divided into groups based on their negative (Neg) or positive response towards Ehrlichia (Ehrl), Rickettsia (Rick), Leishmania (Leish), Borrelia (Borr), Anaplasma (Anapl), and Bartonella (Barto). A Kruskall–Wallis’s test, followed by Dunn’s post hoc comparison test, was applied to determine the statistical effect of negativity and single or multiple positivity on the studied parameters. Results: the group of dogs simultaneously presenting antibodies towards Leishmania, Ehrlichia, and Rickettsia showed higher values of total proteins, globulins, creatine phosphokinase, aspartate aminotransferase, alanine aminotransferase, and amylase than dogs that tested negative or dogs with antibodies toward a single pathogen investigated herein. Conclusions: Our results seem to suggest that exposure to more vector-borne pathogens could lead to greater liver function impairment and a greater inflammatory state. Further investigations are needed in order to better clarify how co-infections affect haematochemical patterns in dogs living in endemic areas of VBDs. Full article
26 pages, 30019 KiB  
Article
LES and RANS Spray Combustion Analysis of OME3-5 and n-Dodecane
by Frederik Wiesmann, Tuan M. Nguyen, Julien Manin, Lyle M. Pickett, Kevin Wan, Fabien Tagliante and Thomas Lauer
Energies 2024, 17(10), 2265; https://doi.org/10.3390/en17102265 (registering DOI) - 08 May 2024
Abstract
Clean-burning oxygenated and synthetic fuels derived from renewable power, so-called e-fuels, are a promising pathway to decarbonize compression–ignition engines. Polyoxymethylene dimethyl ethers (PODEs or OMEs) are one candidate of such fuels with good prospects. Their lack of carbon-to-carbon bonds and high concentration of [...] Read more.
Clean-burning oxygenated and synthetic fuels derived from renewable power, so-called e-fuels, are a promising pathway to decarbonize compression–ignition engines. Polyoxymethylene dimethyl ethers (PODEs or OMEs) are one candidate of such fuels with good prospects. Their lack of carbon-to-carbon bonds and high concentration of chemically bound oxygen effectively negate the emergence of polycyclic aromatic hydrocarbons (PAHs) and even their precursors like acetylene (C2H2), enabling soot-free combustion without the soot-NOx trade-off common for diesel engines. The differences in the spray combustion process for OMEs and diesel-like reference fuels like n-dodecane and their potential implications on engine applications include discrepancies in the observed ignition delay, the stabilized flame lift-off location, and significant deviations in high-temperature flame morphology. For CFD simulations, the accurate modeling and prediction of these differences between OMEs and n-dodecane proved challenging. This study investigates the spray combustion process of an OME35 mixture and n-dodecane with advanced optical diagnostics, Reynolds-Averaged Navier–Stokes (RANS), and Large-Eddy Simulations (LESs) within a constant-volume vessel. Cool-flame and high-temperature combustion were measured simultaneously via high-speed (50 kHz) imaging with formaldehyde (CH2O) planar laser-induced fluorescence (PLIF) representing the former and line-of-sight OH* chemiluminescence the latter. Both RANS and LES simulations accurately describe the cool-flame development process with the formation of CH2O. However, CH2O consumption and the onset of high-temperature reactions, signaled by the rise of OH* levels, show significant deviations between RANS, LES, and experiments as well as between n-dodecane and OME. A focus is set on the quality of the simulated results compared to the experimentally observed spatial distribution of OH*, especially in OME fuel-rich regions. The influence of the turbulence modeling is investigated for the two distinct ambient temperatures of 900 K and 1200 K within the Engine Combustion Network Spray A setup. The capabilities and limitations of the RANS simulations are demonstrated with the initial cool-flame propagation and periodic oscillations of CH2O formation/consumption during the quasi-steady combustion period captured by the LES. Full article
(This article belongs to the Section I1: Fuel)
44 pages, 4198 KiB  
Review
Inkjet Printing with (Semi)conductive Conjugated Polymers: A Review
by Daniil A. Lukyanov and Oleg V. Levin
ChemEngineering 2024, 8(3), 53; https://doi.org/10.3390/chemengineering8030053 (registering DOI) - 08 May 2024
Abstract
Functional inkjet printing is an emerging manufacturing technology for the production of various planar elements and electronic devices. This technology offers affordable freeform and highly customizable production of thin film micron-scale elements on various substrates. Functional inkjet printing employs various inks based on [...] Read more.
Functional inkjet printing is an emerging manufacturing technology for the production of various planar elements and electronic devices. This technology offers affordable freeform and highly customizable production of thin film micron-scale elements on various substrates. Functional inkjet printing employs various inks based on organic and inorganic materials with diverse functional properties, and among them, conjugated polymers are of particular interest due to their electrical, photophysical, and electrochemical properties. This paper provides an overview of inkjet printing with conjugated (semi)conductive polymers, including the fundamentals of the technology and its scope, limitations, and main challenges. Specific attention is drawn to the synthesis and chemistry of these polymers in connection with the patterning and functional properties of the inks composed thereof. Practical aspects of this technology are also highlighted, namely the manufacturing capabilities of the technology and particular applications for the fabrication of various electronic elements and devices. Full article
Show Figures

Figure 1

20 pages, 1051 KiB  
Article
Low-Resolution Optimization for an Unmanned Aerial Vehicle Communication Network under a Passive Reconfigurable Intelligent Surface and Active Reconfigurable Intelligent Surface
by Qiangqiang Yang, Yufeng Chen, Zhiyu Huang, Hongwen Yu and Yong Fang
Electronics 2024, 13(10), 1826; https://doi.org/10.3390/electronics13101826 (registering DOI) - 08 May 2024
Abstract
This paper investigates the optimization of an unmanned aerial vehicle (UAV) network serving multiple downlink users equipped with single antennas. The network is enhanced by the deployment of either a passive reconfigurable intelligent surface (RIS) or an active RIS. The objective is to [...] Read more.
This paper investigates the optimization of an unmanned aerial vehicle (UAV) network serving multiple downlink users equipped with single antennas. The network is enhanced by the deployment of either a passive reconfigurable intelligent surface (RIS) or an active RIS. The objective is to jointly design the UAV’s trajectory and the low-bit, quantized, RIS-programmable coefficients to maximize the minimum user rate in a multi-user scenario. To address this optimization challenge, an alternating optimization framework is employed, leveraging the successive convex approximation (SCA) method. Specifically, for the UAV trajectory design, the original non-convex optimization problem is reformulated into an equivalent convex problem through the introduction of slack variables and appropriate approximations. On the other hand, for the RIS-programmable coefficient design, an efficient algorithm is developed using a penalty-based approximation approach. To solve the problems with the proposed optimization, high-performance optimization tools such as CVX are utilized, despite their associated high time complexity. To mitigate this complexity, a low-complexity algorithm is specifically tailored for the optimization of passive RIS-programmable reflecting elements. This algorithm relies solely on closed-form expressions to generate improved feasible points, thereby reducing the computational burden while maintaining reasonable performance. Extensive simulations are created to validate the performance of the proposed algorithms. The results demonstrate that the active RIS-based approach outperforms the passive RIS-based approach. Additionally, for the passive RIS-based algorithms, the low-complexity variant achieves a reduced time complexity with a moderate loss in performance. Full article

Open Access Journals

Browse by Indexing Browse by Subject Selected Journals
Back to TopTop