Search Results (57)

Due to the high demand for fuel efficiency, electric vehicles have come into the picture, as they only use batteries to power the vehicle. This requires constant charging of the batteries at charging stations, which are costly and impractical to install. But it is possible to install charging stations by making use of photovoltaic (PV) cells and demagnetization currents to self-charge batteries under stand-still conditions. The design of a bidirectional converter with asymmetrical half-bridge converter based on a switched reluctance motor (SRM) drive, using PV for electric vehicles, is implemented in this paper. It consists of developing a control unit (GCU), Li-ion battery pack, and photovoltaic (PV) solar cells that are integrated with a bidirectional converter and asymmetrical half-bridge converter (AHBC) to provide power to the SRM drive. The solar-assisted SRM drive can be operated in either the motoring mode or charging mode. In the motoring-mode GCU, the battery or PV energy can be used in any combination to power the SRM. In the charging-mode PV, the GCU and AC grids are used to charge the battery under stand-still conditions. This work helps in the self-charging of batteries using either the GCU or PV cells, as well as aids in the improvement in the performance characteristics. Also, this work compares the performance metrics for the proposed system and conventional system. The performance of the drive system using PV cells/GCU is evaluated and verified through MatLab/Simulink and experimental results. Full article

In this study, we sequenced and characterized the complete mitochondrial genome of Acorssocheilus spinifer, an endemic stream-dwelling cyprinid species from South China first described in 2006. The mitogenome is 16,591 bp in length and contains the standard set of 37 genes (13 protein-coding genes, 22 tRNA genes, 2 rRNA genes) plus a control region. The genome exhibits typical cyprinid characteristics, with most genes encoded on the H-strand and a nucleotide composition biased toward A + T (55.9%). All tRNA genes display the typical cloverleaf secondary structure, except for tRNA^Ser (GCU), which lacks the dihydrouridine (DHU) arm. Phylogenetic analysis using complete mitogenomes from 14 Acrossocheilus species revealed that 12 species form a monophyletic assemblage with three distinct clades. Within this framework, A. spinifer clusters closely with A. beijiangensis, supporting previous morphological observations. Our findings provide valuable genetic data for further taxonomic refinement and conservation efforts for Chinese barred species of Cyprinidae. Full article

Background/Objectives: In recent years, non-contact room disinfection devices using ultraviolet light and hydrogen peroxide have emerged as disinfection methods. However, data on their usefulness in neonatal intensive care units (NICUs) are limited. Therefore, the aim of the present study was to evaluate the effectiveness of environmental disinfection in controlling methicillin-resistant Staphylococcus aureus (MRSA) outbreaks in a NICU/growing care unit (GCU). Methods: Daily cleaning/disinfection of the patient environment was changed from using a cloth containing quaternary ammonium salts to an agent containing ethanol and surfactant, and terminal cleaning with a pulsed xenon ultraviolet light (PX-UV) non-contact disinfection device was added for patients with confirmed MRSA and those on contact precautions. MRSA incidence and environmental culture results were then compared before and after the method change. Results: The MRSA infection rate was 2.81/1000 patient days before the method change and 0.90/1000 patient days after the change (p = 0.008). Environmental cultures were positive in 12/137 (8.8%) before the change and 0 after the change. There were no adverse events in the neonates due to PX-UV irradiation of the environment. Conclusions: Daily cleaning and disinfection with ethanol and surfactant-containing cleaning disinfectants and a final cleaning with a PX-UV non-contact disinfection device reduced environmental MRSA contamination. In addition to adherence to hand hygiene and contact precautions, reducing MRSA present in the environment may contribute to MRSA control in NICUs and GCUs. Full article

The rapid proliferation of ransomware variants necessitates more effective detection mechanisms, as traditional signature-based methods are increasingly inadequate. These conventional methods rely on manual feature extraction and matching, which are time-consuming and limited to known threats. This study addresses the escalating challenge of ransomware threats in cybersecurity by proposing a novel deep learning model, LSTM-EDadver, which leverages Generative Adversarial Networks (GANs) and Carlini and Wagner (CW) attacks to enhance malware detection capabilities. LSTM-EDadver innovatively generates adversarial examples (AEs) using sequential features derived from ransomware behaviors, thus training deep learning models to improve their robustness and accuracy. The methodology combines Cuckoo sandbox analysis with conceptual lattice ontology to capture a wide range of ransomware families and their variants. This approach not only addresses the shortcomings of existing models but also simulates real-world adversarial conditions during the validation phase by subjecting the models to CW attacks. The experimental results demonstrate that LSTM-EDadver achieves a classification accuracy of 96.59%. This performance was achieved using a dataset of 1328 ransomware samples (across 32 ransomware families) and 519 normal instances, outperforming traditional RNN, LSTM, and GCU models, which recorded accuracies of 90.01%, 93.95%, and 94.53%, respectively. The proposed model also shows significant improvements in F1-score, ranging from 2.49% to 6.64% compared to existing models without adversarial training. This advancement underscores the effectiveness of integrating GAN-generated attack command sequences into model training. Full article

Callitriche species are capable of purifying water, promoting wetland restoration, and providing natural shelters. Moreover, they can be utilized as horticultural plants for landscape greening. However, due to the threats of climate change and environmental degradation, some species within this genus have been listed as endangered. This study utilizes chloroplast genome analysis to provide molecular evidence for the classification and conservation of these species. We conducted a comprehensive sequencing and characterization of the complete chloroplast genomes of four species within the genus Callitriche: C. cophocarpa, C. hermaphroditica, C. palustris, and C. stagnalis. The genome sizes ranged from 150,042 to 150,879 bp, with a GC content of 37.5–37.8% and between 131 and 132 genes. Comparative genomic analysis revealed several highly variable intergenic regions (e.g., rps16–psbK, trnS-GCU–trnG-UCC, ccsA–ndhD, ndhF–rpl32, and trnN-UGG) and the ycf1 gene, highlighting their potential as phylogenetic markers. Phylogenetic analyses confirmed the monophyly of Callitriche and supported C. hermaphroditica as an early-diverging lineage within the genus. Notably, the phylogeny also resolved Hemiphragma and Veronicastrum as sister taxa, contributing insights into evolutionary relationships within Plantaginaceae. This study provides comprehensive chloroplast genomic data for Callitriche, offering valuable molecular markers for phylogenetic research, taxonomic clarification, and conservation of this ecologically significant genus. Full article

Codon usage bias (CUB) refers to the different frequencies with which various codons are utilized within a genome. Examining CUB is essential for understanding genome structure, function, and evolution. However, little was known about codon usage patterns and the factors influencing the nuclear genomes of eight ecologically significant Sapindaceae species widely utilized for food and medicine. In this study, an analysis of nucleotide composition revealed a higher A/T content and showed a preference for A/T at the third codon position in the eight species of Sapindaceae. A correspondence analysis of relative synonymous codon usage explained only part of the variation, suggesting that not only natural selection but also various other factors contribute to selective constraints on codon bias in the nuclear genomes of the eight Sapindaceae species. Additionally, ENC-GC3 plot, PR2-Bias, and neutrality plot analyses indicated that natural selection exerted a greater influence than mutation pressure across these eight species. Among the eight Sapindaceae species, 16 to 26 optimal codons were identified, with two common high-frequency codons: AGA (encoding Arg) and GCU (encoding Ala). The clustering heat map, which included the 8 Sapindaceae species and 13 other species, revealed two distinct clusters corresponding to monocots and dicots. This finding suggested that CUB analysis was particularly effective in elucidating evolutionary relationships at the family level. Collectively, our results emphasized the distinct codon usage characteristics and unique evolutionary traits of the eight Sapindaceae species. Full article

Background: Xi Junecry (Pinellia ternata), a perennial herb of the Araceae family, is indigenous to Xinxian County, Henan Province, China, and is regarded as a premium variety among similar medicinal materials. However, the lack of comprehensive genetic information on Xi Junecry germplasm resources has constrained the cultivation and identification of high-quality varieties. Methods: In this study, six chloroplast genomes of Xi Junecry were assembled and annotated using high-throughput sequencing. Subsequently, comparative analyses were conducted, and a phylogenetic tree was constructed. Results: The six Xi Junecry chloroplast genome lengths ranged from 157,456 to 158,406 bp, and the GC content was between 36.0% and 36.2%. A total of 265 single nucleotide polymorphism sites were identified across the six genomes, with a whole-genome nucleotide diversity (Pi) value of 0.00084. Among the four genomic regions, the small single-copy region exhibited the highest Pi, followed by the large single-copy region, while the inverted repeat region showed the lowest. Nucleotide polymorphism in coding regions was significantly lower than in non-coding regions. Nine hypervariable regions were identified, as follows: ndhE-ndhG, trnN-GUU-ndhF, trnS-GCU-trnG-UCC, atpB-rbcL, psaI, accD-ycf4, psbE-petL, psaC-ndhE, and psbI-trnG-UCC. Positive selection sites were detected in the accD and rbcL genes. Phylogenetic analysis clustered the six Xi Junecry samples into a distinct clade, separating them from other regional Pinellia samples. Conclusions: These findings elucidate the genetic variation levels in Xi Junecry and provide high-variability loci for population history inference, genetic diversity assessment, species domestication studies, and new cultivar development. Full article

Due to the growth of biodiesel production, utilization of the glycerol formed as a by-product is still of considerable importance. This study is devoted to a novel approach for glycerol hydrogenolysis with use of in situ generated Cu-ZnO catalysts. The main product formed is 1,2-propanediol, with the by-products being lactic acid and ethylene glycol. The Cu-ZnO catalysts are characterized by AAS, XRD, XPS, SEM, TEM, EDX, BET, and chemisorption N₂O. The proportion of ZnO turns out to have a significant effect on the activity and selectivity of the catalyst formed. Increasing the ZnO content enables one to obtain more dispersed, active, selective, and agglomeration-resistant catalysts. The transition from monometallic Cu catalysts to Cu-ZnO with a ZnO content of 65 wt% allows one to increase selectivity from 74 to 86%, TOF from 0.136 to 0.511 s⁻¹, and S_Cu from 1.9 to 7.1 m²/g-Cu. The morphology of the synthesized Cu-ZnO catalysts resembles the structure of oxide/metal inverse catalysts. Full article

Recent developments in aircraft electrical technology, such as the design and production of more electric aircraft (MEA) and major steps in the development of all-electric aircraft (AEA), have had a significant impact on aircraft’s electrical power systems (EPSs). However, the EPSs of the latest aircraft produced by the main players in the market, Airbus with the Neo series and Boeing with the NG and MAX series are still completely traditional and based on the constant speed constant frequency (CSCF) configuration. For alternating current ones, the EPS is composed of the following: prime movers, namely the aircraft turbofan engine (TE); the electrical power source, i.e., the integrated drive generator (IDG); the command and control system, the generator control unit (GCU); the transmission and the system distribution system; the protection system, i.e., the CBs (circuit breakers); and the electrical loads. This paper presents the analysis of this system using the Simscape package from Simulink v 8.7, a MATLAB v 9.0 program, which is actually the development of some systems designed in two previous personal papers. For the first time in the literature, a complete MATLAB modelled EPS system was presented, i.e., the aircraft turbofan engine model, driving the constant speed drive system (CSD) (model presented in the first reference as a standalone type and with different parameters), linked to the synchronous generator (SG) (model presented in second reference for lower power and rotational speed) in the so-called integrated drive generator (IDG) and electrical loads. Full article

Unmanned aerial vehicles (UAVs) have become a promising application for future communication and spectrum awareness due to their favorable features such as low cost, high mobility, and ease of deployment. Nevertheless, the jamming resistance appears to be a new challenge in multi-UAV cooperative communication scenarios. This paper focuses on designing trajectory planning and power allocation for efficient control and reliable communication in a ground control unit (GCU)-controlled UAV network, where the GCU coordinates multi-UAV systems to execute tasks amidst multiple jammers with imperfect location and power information. Specifically, this paper formulates a nonconvex semi-infinite optimization problem to maximize the average worst-case signal-to-interference-plus-noise ratio (SINR) among multiple UAVs by designing robust flight paths and power control strategy under stringent energy and mobility constraints. To efficiently address this issue, this paper proposes a powerful iterative algorithm utilizing the S-procedure and the successive convex approximation (SCA) method. Extensive simulations validate the effectiveness of the proposed strategy. Full article

Arrow bamboo (Fargesia qinlingensis) is endemic to the Qinling Mountains and has remarkable adaptive resilience to changing climates. However, its complete mitogenome remains unknown. Using the Illumina and PacBio HiFi sequencing platforms, we found that the mitogenome assembly of the F. qinlingensis has a multi-branched skeleton comprising three linear molecules (M1, M2, and M3), with a length of 442,368 bp and a GC content of 44.05%. Thirty-five unique PCGs were identified in the complete mitogenome, including twenty-four core structural genes, eleven noncore structural genes, three rRNAs, and sixteen tRNAs. The GCU for alanine and CAA for glutamine represented the most significant frequency (RSCU = 1.55) in the codon usage preference. A total of 51, 28, and 14 SSRs were determined on M1, M2, and M3, respectively. The mitogenome contained 149 pairs of dispersed repeats with lengths greater than 30 bp, the most abundant of which were 82 forward and 67 palindromic repeats. A long repeat sequence (14,342 bp) was characterized in mediating mitogenome recombination. DNA transfer analyses suggested that 44 MTPTs (30,943 bp, 6.99%) originated from the plastome. Among the 482 potential C-U/T RNA-editing sites predicted in 35 PCGs, ccmFn (38 times) and ccmC (36 times) shoed the highest frequency. Collinearity and phylogenetic trees revealed the close relationship between F. qinlingensis and Bambusa oldhamii. The primary features of the mitogenome of F. qinlingensis will help decipher the functional mitochondrial traits related to growth performance and climate resilience. Moreover, our findings provide insights into the evolution, environmental adaptation, and sustainable use of subalpine bamboo resources in the Qinling Mountains. Full article

Dryas octopetala var. asiatica, a dwarf shrub belonging to the Rosaceae family and native to Asia, exhibits notable plasticity in photosynthesis in response to temperature variations. However, the codon usage patterns and factors influencing them in the chloroplast genome of this species have not yet been documented. This study sequenced and assembled the complete genome of D. octopetala var. asiatica. The annotated genes in the chloroplast genome were analyzed for codon composition through multivariate statistical methods including a neutrality plot, a parity rule 2 (PR2) bias plot, and an effective number of codons (ENC) plot using CodonW 1.4.2 software. The results indicated that the mean GC content of 53 CDSs was 38.08%, with the average GC content at the third codon base position being 27.80%, suggesting a preference for A/U(T) at the third codon position in chloroplast genes. Additionally, the chloroplast genes exhibited a weak overall codon usage bias (CUB) based on ENC values and other indicators. Correlation analysis showed a significant negative correlation between ENC value and GC2, an extremely positive correlation with GC3, but no correlation with GC1 content. These findings highlight the importance of the codon composition at the third position in influencing codon usage bias. Furthermore, our analysis indicated that the CUB of the chloroplast genome of D. octopetala var. asiatica was primarily influenced by natural selection and other factors. Finally, this study identified UCA, CCU, GCU, AAU, GAU, and GGU as the optimal codons. These results offer a foundational understanding for genetic modification and evolutionary dynamics of the chloroplast genome of D. octopetala var. asiatica. Full article

In 2023, most parts of the world experienced exceptional heat. In particular, anomalous warm temperatures and heatwave events were evidenced across South America during the second half of the year. The situation was particularly critical in the Amazon region in terms of not only hydrometeorological drought but also ecological and socioeconomic impacts. In this study, remote-sensing data collected from the Moderate Resolution Imaging Spectroradiometer (MODIS) were used to observe the changes in temperature and vegetation across Amazonia during the exceptional drought of 2023. This analysis was based on anomalies in the land surface temperature (LST) and vegetation indices: the enhanced vegetation index (EVI) and the normalized difference vegetation index (NDVI). The amplitude of the LST (AMP-LST), an indicator of the energy partitioning between the latent and sensible heat flux, and fire counts were also considered. The results show widespread and extreme warming across Amazonia during the austral spring in 2023, accompanied by a decline in vegetation greenness, water stress conditions across northern Amazonia, and an enhanced fire occurrence across central and northern Amazonia. Full article

Cynanchum belongs to the Apocynaceae family and is a morphologically diverse genus that includes around 200 shrub or perennial herb species. Despite the utilization of CPGs, few molecular phylogenetic studies have endeavored to elucidate infrafamilial relationships within Cynanchum through extensive taxon sampling. In this research, we constructed a phylogeny and estimated divergence time based on the chloroplast genomes (CPGs) of nine Cynanchum species. We sequenced and annotated nine chloroplast (CP) genomes in this study. The comparative analysis of these genomes from these Cynanchum species revealed a typical quadripartite structure, with a total sequence length ranging from 158,283 to 161,241 base pairs (bp). The CP genome (CPG) was highly conserved and moderately differentiated. Through annotation, we identified a total of 129–132 genes. Analysis of the boundaries of inverted repeat (IR) regions showed consistent positioning: the rps19 gene was located in the IRb region, varying from 46 to 50 bp. IRb/SSC junctions were located between the trnN and ndhF genes. We did not detect major expansions or contractions in the IR region or rearrangements or insertions in the CPGs of the nine Cynanchum species. The results of SSR analysis revealed a variation in the number of SSRs, ranging from 112 to 150. In five types of SSRs, the largest number was mononucleotide repeats, and the smallest number was hexanucleotide repeats. The number of long repeats in the cp genomes of nine Cynanchum species was from 35 to 80. In nine species of Cynanchum, the GC3s values ranged from 26.80% to 27.00%, indicating a strong bias towards A/U-ending codons. Comparative analyses revealed four hotspot regions in the CPG, ndhA-ndhH, trnI-GAU-rrn16, psbI-trnS-GCU, and rps7-ndhB, which could potentially serve as molecular markers. In addition, phylogenetic tree construction based on the CPG indicated that the nine Cynanchum species formed a monophyletic group. Molecular dating suggested that Cynanchum diverged from its sister genus approximately 18.87 million years ago (Mya) and species diversification within the Cynanchum species primarily occurred during the recent Miocene epoch. The divergence time estimation presented in this study will facilitate future research on Cynanchum, aid in species differentiation, and facilitate diverse investigations into this economically and ecologically important genus. Full article

Understanding the interactions in hybrid systems based on graphene and functional oxides is crucial to the applicability of graphene in real devices. Here, we present a study of the structural defects occurring on graphene during the early stages of the growth of CoO, tailored by the electronic coupling between graphene and the substrate in which it is supported: as received pristine graphene on polycrystalline copper (coupled), cleaned in ultra-high vacuum conditions to remove oxygen contamination, and graphene transferred to SiO₂/Si substrates (decoupled). The CoO growth was performed at room temperature by thermal evaporation of metallic Co under a molecular oxygen atmosphere, and the early stages of the growth were investigated. On the decoupled G/SiO₂/Si samples, with an initial low crystalline quality of graphene, the formation of a CoO wetting layer is observed, identifying the Stranski-Krastanov growth mode. In contrast, on coupled G/Cu samples, the Volmer-Weber growth mechanism is observed. In both sets of samples, the oxidation of graphene is low during the early stages of growth, increasing for the larger coverages. Furthermore, structural defects are developed in the graphene lattice on both substrates during the growth of CoO, which is significantly higher on decoupled G/SiO₂/Si samples mainly for higher CoO coverages. When approaching the full coverage on both substrates, the CoO islands coalesce to form a continuous CoO layer with strip-like structures with diameters ranging between 70 and 150 nm. Full article