ALBERT

Description: We mainly focus on the effects of small changes of parameters on the dynamics of charged particles around Kerr black holes surrounded by an external magnetic field, which can be considered as a tidal environment. The radial motions of charged particles on the equatorial plane are studied via an effective potential. It is found that the particle energies at the local maxima values of the effective potentials increase with an increase in the black hole spin and the particle angular momenta, but decrease with an increase of one of the inductive charge parameter and magnetic field parameter. The radii of stable circular orbits on the equatorial plane also increase, whereas those of the innermost stable circular orbits decrease. On the other hand, the effects of small variations of the parameters on the orbital regular and chaotic dynamics of charged particles on the non-equatorial plane are traced by means of a time-transformed explicit symplectic integrator, Poincaré sections and fast Lyapunov indicators. It is shown that the dynamics sensitivity depends on small variations in the inductive charge parameter, magnetic field parameter, energy, and angular momentum. Chaos occurs easily as each of the inductive charge parameter, magnetic field parameter, and energy increases but is weakened as the angular momentum increases. When the dragging effects of the spacetime increase, the chaotic properties are not always weakened under some circumstances.

Description: In the single-polyelectrolyte aqueous phase separation (APS) approach, membranes are prepared by precipitating a weak polyelectrolyte from a concentrated aqueous solution using a pH switch. This has proven to be a versatile and more sustainable method compared to conventional approaches as it significantly reduces the use of organic solvents. Poly(styrene-alt-maleic acid) (PSaMA) is a polymer that has been extensively investigated for APS and has been the basis for both open and dense membranes with good performances. These membranes are chemically crosslinked and, in this work, we further investigated ultrafiltration (UF) and nanofiltration (NF) membranes prepared with PSaMA for their stability in various organic solvents and under different pH conditions. It was shown that these membranes had stable performances in both isopropanol (IPA) and toluene, and a slightly reduced performance in N-methyl-2-pyrollidone (NMP). However, PSaMA did not perform well as a selective layer in these solvents, indicating that the real opportunity would be to use the UF-type PSaMA membranes as solvent-stable support membranes. Additionally, the membranes proved to be stable in an acidic-to-neutral pH regime (pH 2–7); and, due to the pH-responsive nature of PSaMA, for the NF membranes, a pH-dependent retention of Mg2+ and SO42− ions was observed and, for the UF membranes, a strong responsive behavior was observed, where the pH can be used to control the membrane permeability. However, long-term exposure to elevated pH conditions (pH 8–10) resulted in severe swelling of the NF membranes, resulting in defect formation, and compaction of the UF membranes. For the UF membranes, this compaction did prove to be reversible for some but not all of the membrane samples measured. These results showed that in aqueous systems, membranes prepared with PSaMA had interesting responsive behaviors but performed best at neutral and acidic pH values. Moreover, the membranes exhibited excellent stability in the organic solvents IPA and toluene

Description: Real-time PCR is widely used to study the relative abundance of mRNA due to its specificity, sensitivity, and repeatability quantification. However, relative quantification requires a reference gene, which should be stable in its expression, showing lower variation by experimental conditions or tissues. The aim of this study was to evaluate the stability of the expression of five commonly used reference genes (actb, ywhaz, b2m, sdha, and 18s rRNA) at different physiological stages (alert and emergency) in three different cattle breeds. In this study, five genes (actb, ywhaz, b2m, sdha, and 18s rRNA) were selected as candidate reference genes for expression studies in the whole blood from three cattle breeds (Romosinuano, Gyr, and Brahman) under heat stress conditions. The transcription stability of the candidate reference genes was evaluated using geNorm and NormFinder. The results showed that actb, 18SrRNA, and b2m expression were the most stable reference genes for whole blood of Gyr and Brahman breeds under two states of livestock weather safety (alert and emergency). Meanwhile, actb, b2m, and ywhaz were the most stable reference genes for the Romosinuano breed.

Description: Klebsiella pneumoniae is an increasing threat to public health and represents one of the most concerning pathogens involved in life-threatening infections. The resistant and virulence determinants are coded by mobile genetic elements which can easily spread between bacteria populations and co-evolve with its genomic host. In this study, we present the full genomic sequences, insertion sites and phylogenetic analysis of 150 prophages found in 40 K. pneumoniae clinical isolates obtained from an outbreak in a Portuguese hospital. All strains harbored at least one prophage and we identified 104 intact prophages (69.3%). The prophage size ranges from 29.7 to 50.6 kbp, coding between 32 and 78 putative genes. The prophage GC content is 51.2%, lower than the average GC content of 57.1% in K. pneumoniae. Complete prophages were classified into three families in the order Caudolovirales: Myoviridae (59.6%), Siphoviridae (38.5%) and Podoviridae (1.9%). In addition, an alignment and phylogenetic analysis revealed nine distinct clusters. Evidence of recombination was detected within the genome of some prophages but, in most cases, proteins involved in viral structure, transcription, replication and regulation (lysogenic/lysis) were maintained. These results support the knowledge that prophages are diverse and widely disseminated in K. pneumoniae genomes, contributing to the evolution of this species and conferring additional phenotypes. Moreover, we identified K. pneumoniae prophages in a set of endolysin genes, which were found to code for proteins with lysozyme activity, cleaving the β-1,4 linkages between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in the peptidoglycan network and thus representing genes with the potential for lysin phage therapy.

Description: Surface modification of membranes is an effective approach for imparting unique characteristics and additional functionalities to the membranes. Chemical grafting is a commonly used membrane modification technique due to its versatility in tailoring and optimizing the membrane surface with desired functionalities. Various types of polymers can be precisely grafted onto the membrane surface and the operating conditions of grafting can be tailored to further fine-tune the membrane surface properties. This review focuses on the recent strategies in improving the surface design of liquid separation membranes through grafting-from technique, also known as graft polymerization, to improve membrane performance in wastewater treatment and desalination applications. An overview on membrane technology processes such as pressure-driven and osmotically driven membrane processes are first briefly presented. Grafting-from surface chemical modification approaches including chemical initiated, plasma initiated and UV initiated approaches are discussed in terms of their features, advantages and limitations. The innovations in membrane surface modification techniques based on grafting-from techniques are comprehensively reviewed followed by some highlights on the current challenges in this field. It is concluded that grafting-from is a versatile and effective technique to introduce various functional groups to enhance the surface properties and separation performances of liquid separation membranes.

Description: The exploration and rational design of easily separable and highly efficient sorbents with satisfactory capability of extracting radioactive uranium (U)-containing compound(s) are of paramount significance. In this study, a novel magnetic hydroxyapatite (HAP) composite (HAP@ CoFe2O4), which was coupled with cobalt ferrite (CoFe2O4), was rationally designed for uranium(VI) removal through a facile hydrothermal process. The U(VI) ions were rapidly removed using HAP@ CoFe2O4 within a short time (i.e., 10 min), and a maximum U(VI) removal efficiency of 93.7% was achieved. The maximum adsorption capacity (Qmax) of the HAP@CoFe2O4 was 338 mg/g, which demonstrated the potential of as-prepared HAP@CoFe2O4 in the purification of U(VI) ions from nuclear effluents. Autunite [Ca(UO2)2(PO4)2(H2O)6] was the main crystalline phase to retain uranium, wherein U(VI) was effectively extracted and immobilized in terms of a relatively stable mineral. Furthermore, the reacted HAP@CoFe2O4 can be magnetically recycled. The results of this study reveal that the suggested process using HAP@CoFe2O4 is a promising approach for the removal and immobilization of U(VI) released from nuclear effluents.

Description: Sowing time, as an element, is important to improving the adaptation of cultivars to environmental conditions and to achieving high seed yields. The field experiment was conducted from 2018–2019 at the Experimental Station of Vytautas Magnus University Agriculture Academy. The experimental design included treatments with different sowing dates: eight sowing dates in 2018 and 10 sowing dates in 2019. The first sowing of spring rapeseed was carried out when the soil reached its physical maturity, i.e., it did not stick to agricultural implements and it crumbled well. The other sowing dates were every seven subsequent days. From 2018–2019, the rapeseed emerged as best in early May (3 and 4 May), and later sowing reduced the emergence of rapeseed. In 2018, most pods were formed on one plant when the rapeseed was sown (on 1 June), compared to other sowings, on average 2.8 times more. In 2019, most pods were formed by the latest-sown rapeseed (7 June), from 1.4 to 2.7 times more compared to previously sown crops. In 2018, the sowing time of spring rapeseed did not have a significant effect on the number of seeds in one pod. In 2019, it was found that the rapeseed formed most of the seeds in the pod at a similar time as in 2018: the sowings of 19 April and 7 June. The average number of seeds in the pod was significantly reduced by early sowing (5 April). In 2019, the highest 1000-seed weight was found at the earliest-sown crop (5 April), which was on average 18.0% higher compared to the later sowings. The 1000-seed weight of the last-sown rapeseed (7 June) was the lowest. In 2018, the yields of early-sown (20 April) spring rapeseed were the highest. Later sowing significantly reduced the yields by 20.7 to 48.2%. In 2019, the highest seed yield was obtained after sowing spring rapeseed in late April (26 April); it was significant, on average, 1.9 times higher than the yields of spring rapeseed sown from 3 May to 7 June. Meteorological conditions had a stronger effect on the field emergence and yield components of spring rapeseed than the sowing date.

Description: Although remote sensors have been increasingly providing dense data and deriving reanalysis data for inversion of particulate matters, the use of these data is considerably limited by the ground monitoring samples and conventional machine learning models. As regional criteria air pollutants, particulate matters present a strong spatial correlation of long range. Conventional machine learning cannot or can only model such spatial pattern in a limited way. Here, we propose a method of a geographic graph hybrid network to encode a spatial neighborhood feature to make robust estimation of coarse and fine particulate matters (PM10 and PM2.5). Based on Tobler’s First Law of Geography and graph convolutions, we constructed the architecture of a geographic graph hybrid network, in which full residual deep layers were connected with graph convolutions to reduce over-smoothing, subject to the PM10–PM2.5 relationship constraint. In the site-based independent test in mainland China (2015–2018), our method achieved much better generalization than typical state-of-the-art methods (improvement in R2: 8–78%, decrease in RMSE: 14–48%). This study shows that the proposed method can encode the neighborhood information and can make an important contribution to improvement in generalization and extrapolation of geo-features with strong spatial correlation, such as PM2.5 and PM10.

Description: The objective of this study was to evaluate the effects of Bacillus subtillis PB6, chromium propionate or a combination of the two on the performance, egg and eggshell quality, nutrient metabolizability and serum biochemistry of layer breeders. White Plymouth Rock and Red Rhodes Island breeder hens at 55 weeks of age were allocated in individual cages using a completely randomized block design with 16 replicates. Hens were fed control, control + probiotic (500 g/ton of Bacillus subtilis PB6), control + CrProp (50 g/ton of chromium propionate) and control + probiotic + CrProp diets from 55 to 70 weeks of age. Productive parameters and eggshell quality as well as cortisol and blood biochemistry were grouped each 28 d as well as for the overall period. The metabolizability of nutrients and energy was determined at 70 weeks of age. In the overall period, hens fed the control + probiotic or control + probiotic + CrProp diets had significantly higher egg production, egg mass, shell percentage, thickness and shell strength. The metabolizability of dry matter, nitrogen and energy increased in hens that were fed the control + probiotic + CrProp diet. In conclusion, diets supplemented with Bacillus subtillis PB6 and chromium propionate resulted in improved productive performance, eggshell quality and nutrient metabolizability of layer breeders, without modifying serum cortisol, albumin and triglycerides.

Description: Mycotoxins are toxic secondary metabolites produced by fungi on agricultural produce. Mycotoxins can be cytotoxic, genotoxic, mutagenic, and teratogenic, and they are persistent threats to human and animal health. Consumption of mycotoxin-contaminated maize can cause cancer and even sudden death. Health hazards can also occur from consuming products from animals fed with mycotoxin-contaminated feed or forage. The main mode of spread of mycotoxigenic fungi is through air-borne spores originating from soil or plant debris, although some fungi can also spread through infected seed-to-seedling transmission, ultimately followed by contamination of the harvestable product. This perspective assesses opportunities to prevent mycotoxigenic fungal infection in maize seeds produced for sowing as an important starting point of crop contamination. A case study of Nigeria showed infection in all tested farmer-produced, seed company, and foundation seed samples. A schematic overview of the formal and informal seed systems is presented to analyze their contribution to fungal infection and mycotoxin contamination in the maize value chain, as well as to set criteria for successful control. We recommend an integrated approach to control mycotoxigenic fungal infection, including resistant varieties and other control methods during seed production, grain production, and grain storage, with an important role in maintaining seed health.