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The movement and aggregation of cellulose particles reduce the insulation performance of the transformer, thereby increasing the risk of oil-paper insulation failure. In this study, an experimental platform is constructed to synchronously record the particle motion images and voltage, allowing for the observation of the typical motion mode of the particle between electrodes, namely, the back-and-forth motion mode, under alternating current (ac) voltage. The connection between the cellulose particle’s movement and the ac voltage phase in this motion mode is subsequently examined, delving into the trajectory of particle motion, which is captured through the implementation of image processing technology. The results indicate that the cellulose particle does not always move in the direction of the electric field lines. Within one cycle of the power frequency voltage waveform, the particle exhibits two states: staying on the electrode surface and moving in the oil gap, with each state occupying approximately half of the time. In addition, the cellulose particle consistently moves within the oil gap during the second and fourth quadrants of the voltage cycle, while it remains on the electrodes during the first and third quadrants. Subsequently, an analysis model is conducted to simulate the particle’s trajectory as it moves between the electrodes, coupled with the calculations and analysis of the variation in the velocity and the primary forces exerted on the particle. The results show that the particle tends to move toward the more concentrated area of the electric field, and the closer it is to the center of the spherical electrode, the denser its motion trajectory is. This study provides a theoretical basis for the subsequent insulation hazard assessment of cellulose impurities.

Based on operating experience, internal pressure fluctuations caused by vibration in oil-immersed electrical equipment can lead to bubble formation within the narrow gap. Bubbles significantly reduce the electrical strength and insulation level of equipment. The main aim of this study is to determine the mechanism and characteristics of bubble initiation within the microgap induced by low-frequency vibration. A model of the microgap with wall vibration is constructed, and based on fluid mechanics and cavitation theory, the criterion of cavitation caused by the microgap wall vibration is proposed. Then, an experimental platform is built to observe the bubbling phenomena due to vibration within the microgap, and the process of bubble initiation is analyzed. Finally, the effect of microgap geometry on the threshold characteristics of bubble initiation under vibration is obtained. The results show that bubble initiation within the microgap is closely related to the pressure in the insulating oil. The bubbling phenomena can be observed at the microgap when the pressure exceeds a certain threshold. The process of bubble initiation within the microgap follows a periodic pattern with vibration, and bubbles initiate during the expansion of the microgap. Furthermore, reducing the initial spacing of the microgap or increasing the size of vibrating plates can promote bubble initiation within the microgap. The study contributes to understanding the mechanism and characteristics of bubble generation within microgaps of oil-immersed electrical equipment. It also provides theoretical support for the insulation risk assessment and measures to suppress bubble formation within microgaps in oil-immersed electrical equipment.

The bubbles generated in the oil-paper insulation and their movement will reduce the dielectric strength and lead to insulation failure in power transformers. To explore bubble motion characteristics and the possible accumulation location, a bubble motion simulating model is established coupling with the electric field and the oil flow. The motion and deformation of the bubble in the oil gap at the top of high-voltage winding are simulated under ac electric field. The results show that the bubble motion trajectory presents an S-shape during the rising period near the T-cross oil gap driven by the electric field force and pressure from the oil flow. During the motion process, the bubble undergoes periodic deformation with a frequency of 100 Hz. The presence of the bubble changes the electric field distribution, bringing about a more significant distortion of the electric field. In the L-shaped oil gap near the electrostatic ring, the bubble motion is mainly driven by pressure from the oil flow. Moreover, if the oil flow velocity is very slow, the bubbles may accumulate on the inner wall of the angle ring, which will give rise to further deterioration of insulation. A test platform is built to observe the bubble trajectory in the oil gap and the results are consistent with simulated in the model. The results obtained are of great significance to present a better understanding of the bubble dynamics in the transformer oil gaps. Insulation failure risk caused by bubble motion and accumulation in oil gap needs to be paid attention to and further explored by researchers.

Bubbles are typical defects in the oil-paper insulation system of transformers. The partial discharge (PD) caused by them significantly reduces the insulation performance of oil-paper insulation, posing a great threat to the insulation of transformers. However, there is currently limited research on the evolution process of bubble PD and the deterioration characteristics of oil-immersed pressboard (OIPB) caused by bubble PD. This article first constructs a bubble PD test platform, using air bubbles in stagnant oil as the research object. In the research object, the shape, volume, and gas composition inside the bubbles will change with the variation of voltage and PD, which can fully reflect the accumulative effect of long-term PD in bubbles. Then, this article conducts experimental research on the evolution and breakdown process of bubble PD. The results show that the evolution of PD inside bubbles may greatly change the phase-resolved PD (PRPD) spectrum, and this article proposes a possible explanation for the evolution of bubble PD: the gas composition inside the bubble dominates the evolution of PD. Finally, based on the inhibitory or promoting effects of different fault gases on the evolution of PD, this article establishes a connection between bubble PD and the deterioration of OIPB. Scanning electron microscopy (SEM) is used to analyze the microstructure of OIPB in different damage states, and the micromechanism of bubble deformation and insulation failure is discussed. The work helps to understand the PD characteristics of bubble defects and the mechanism of causing insulation failure in OIPB, providing a reference for risk assessment of transformers.

As deep learning (DL) technologies become ubiquitous, GPU clusters are deployed for inference tasks with consistent service level objectives (SLOs). Efficiently utilizing multiple GPUs is crucial for throughput and cost-effectiveness. This article addresses the challenges posed by dynamic input and NVIDIA MIG in scheduling DL workloads. We present ElasticBatch, a scheduling system that simplifies configuration through bucketization and employs a machine learning-based pipeline to optimize settings. Our experiments demonstrate that ElasticBatch achieves a 50% reduction in GPU instances compared to MIG disablement, increases GPU utilization by 1.4% to 6.5% over an ideal scheduler and significantly reduces profiling time. This research contributes to the discourse on efficient utilization of GPU clusters. ElasticBatch's effectiveness in mitigating challenges posed by dynamic inputs and NVIDIA MIG underscores its potential to optimize GPU cluster performance, providing tangible benefits in terms of reduced instances, increased utilization, and significant time savings in real-world deployment scenarios.

In real-time human-machine interaction (HMI) applications, hand gesture recognition (HGR) requires high accuracy with low latency. Surface electromyography (sEMG), a physiological electrical signal reflecting muscle activation, is extensively used in HMI. Recently, transient sEMG, generated during the gesture transitions, has been employed in HGR to achieve lower observational latency compared to steady-state sEMG. However, the use of long feature windows (up to 200 ms) still make it less desirable in low-latency HMI. In addition, most studies have relied on remote computing, where remote data processing and large data transfer result in high computation and network latency. In this paper, we proposed a method leveraging transient high density sEMG (HD-sEMG) and in-sensor computing to achieve low-latency HGR. An sEMG contrastive convolution network (sCCN) was proposed for HGR. The mean absolute value and its average integration were used to train the sCCN in a contrastive learning manner. In addition, all signal acquisition, data processing, and pattern recognition processes were deployed within designed sensor for in-sensor computing. Compared to the state-of-the-art study using multi-channel 200-ms transient sEMG, our proposed method achieved a comparable HGR accuracy of 0.963, and a 58% lower observational latency of only 84 ms. In-sensor computing realizes a 4 times lower computation latency of 3 ms, and significantly reduces the network latency to 2 ms. The proposed method offers a promising approach to achieving low-latency HGR without compromising accuracy. This facilitates real-time HMI in biomedical applications such as prostheses, exoskeletons, virtual reality, and video games.

•We describe a strain of S. Typhimurium resistant to 28 antibiotics.•The strain carried 54 AMR genes, and blaOKP-B-10was found in Salmonellafirst.•The strain carried two novel plasmids.•pSH11G993-1 carried 14 AMR genes, including blaCMY-2, mphA, and ermB.•pSH11G993-2 endowed the strain virulence and resistance.

The quality of the solid–electrolyte interphase is crucial for the performance of most battery chemistries, but its formation dynamics during operation are not well understood due to a lack of reliable operando characterization techniques. Herein, we report a dynamic, non-invasive, operando reflection interference microscope to enable the real-time imaging of the solid–electrolyte interphase during its formation and evolution processes with high sensitivity. The stratified structure of the solid–electrolyte interphase formed during four distinct steps includes the emergence of a permanent inner inorganic layer enriched in LiF, a transient assembly of an interfacial electrified double layer and a consequent emergence of a temporary outer organic-rich layer whose presence is reversible with electrochemical cycling. Reflection interference microscope imaging reveals an inverse correlation between the thicknesses of two interphasial subcomponents, implying that the permanent inorganic-rich inner layer dictates the organic-rich outer layer formation and lithium nucleation. The real-time visualization of solid–electrolyte interphase dynamics provides a powerful tool for the rational design of battery interphases.

In recent years, high-density surface electromyography (HD-sEMG) has been applied for cancelable authentication of wearable devices used in healthcare applications. However, previous studies focused on the forearm or hand, whereas the wrist is more comfortable for practical use. Covering a larger area with fewer electrodes (16 channels on the wrist versus 256 channels on the forearm) also reduces the chance of electrode corruption and improves the stability of the authentication system. In addition, fast dynamic gestures are more desirable than static gestures for real-time authentication. Shorter gesture execution time also makes dynamic gesture codes harder to record by imposters. We propose a cancelable real-time biometric system via wrist-worn HD-sEMG and dynamic gestures. A wearable wristband was designed to collect HD-sEMG signals. Based on a dataset with 12 dynamic gestures, we realized a fast real-time authentication. It achieved an equal error rate (EER) of 0.0039 even when imposters entered a correct gesture code. The cancelability was confirmed with an EER of 0.0018. The real-time authentication with an authentication accuracy of 96.7% and a low latency of 64 ms makes it practical in healthcare applications. These results demonstrate the feasibility of wrist-worn biometrics, which allows secure healthcare applications without compromising the user experience.

Previous genome-wide association studies (GWASs) of stroke — the second leading cause of death worldwide — were conducted predominantly in populations of European ancestry1,2. Here, in cross-ancestry GWAS meta-analyses of 110,182 patients who have had a stroke (five ancestries, 33% non-European) and 1,503,898 control individuals, we identify association signals for stroke and its subtypes at 89 (61 new) independent loci: 60 in primary inverse-variance-weighted analyses and 29 in secondary meta-regression and multitrait analyses. On the basis of internal cross-ancestry validation and an independent follow-up in 89,084 additional cases of stroke (30% non-European) and 1,013,843 control individuals, 87% of the primary stroke risk loci and 60% of the secondary stroke risk loci were replicated (P< 0.05). Effect sizes were highly correlated across ancestries. Cross-ancestry fine-mapping, in silico mutagenesis analysis3, and transcriptome-wide and proteome-wide association analyses revealed putative causal genes (such as SH3PXD2Aand FURIN) and variants (such as at GRK5and NOS3). Using a three-pronged approach4, we provide genetic evidence for putative drug effects, highlighting F11, KLKB1, PROC, GP1BA, LAMC2 and VCAM1 as possible targets, with drugs already under investigation for stroke for F11 and PROC. A polygenic score integrating cross-ancestry and ancestry-specific stroke GWASs with vascular-risk factor GWASs (integrative polygenic scores) strongly predicted ischaemic stroke in populations of European, East Asian and African ancestry5. Stroke genetic risk scores were predictive of ischaemic stroke independent of clinical risk factors in 52,600 clinical-trial participants with cardiometabolic disease. Our results provide insights to inform biology, reveal potential drug targets and derive genetic risk prediction tools across ancestries.

Right ventricular (RV) structure and function influence the morbidity and mortality from coronary artery disease (CAD), dilated cardiomyopathy (DCM), pulmonary hypertension and heart failure. Little is known about the genetic basis of RV measurements. Here we perform genome-wide association analyses of four clinically relevant RV phenotypes (RV end-diastolic volume, RV end-systolic volume, RV stroke volume, RV ejection fraction) from cardiovascular magnetic resonance images, using a state-of-the-art deep learning algorithm in 29,506 UK Biobank participants. We identify 25 unique loci associated with at least one RV phenotype at P< 2.27 ×10−8, 17 of which are validated in a combined meta-analysis (n= 41,830). Several candidate genes overlap with Mendelian cardiomyopathy genes and are involved in cardiac muscle contraction and cellular adhesion. The RV polygenic risk scores (PRSs) are associated with DCM and CAD. The findings substantially advance our understanding of the genetic underpinning of RV measurements.

Salmonellaspp. are among the most prevalent foodborne pathogens. Rapid identification of etiologic agents during foodborne outbreaks is of great importance. In this study, we report a traceback investigation of a Salmonellaoutbreak in China. Metagenomic sequencing of suspected food samples was performed on MinION and MiSeq platforms. Real-time nanopore sequencing analysis identified reads belonging to the Enterobacteriaceaefamily. MiSeq sequencing identified 63 reads specifically mapped to Salmonella. Conventional methods including quantitative-PCR and culture-based isolation confirmed as Salmonella entericaserovar Typhimurium. The foodborne outbreak of SalmonellaTyphimurium was further recognized by whole-genome sequencing and pulsed-field gel electrophoresis analysis. Our study demonstrates the ability of metagenomic sequencing to rapidly identify enteric pathogens directly from food samples. These results highlight the capacity of metagenomic sequencing to deliver actionable information rapidly and to expedite the tracing and identification of etiologic agents during foodborne outbreaks.

Supplemental Digital Content is available in the text.

Developing functional porous materials as a platform for the heterogeneous catalytic oxidation reaction provides a good way to solve the high environmental issues resulted by traditional oxidation processes in the industry. This article reported a design and facile synthesis of N-rich functional porous organic polymers with mesopores such as Azo-POP-4, Azo-POP-5, and Azo-POP-6 based on the triaminotriphenylazobenzene subunit for the first time. The nitrogen-rich POPs with the triaminotriphenylazobenzene subunit was found to remove 85% of copper ions from water within 30 min. The as-synthesized Cu@Azo-POP-4 demonstrated high catalytic reactivity and selectivity in aerobic C–H bond oxidation to afford the desired ketones in high yield. In addition, the catalyst could be reused easily five times without decreasing the reactivity, which will help to design catalysts reducing environmental pollution and advance the chemical technology.

Species of Artemiaare regionally endemic branchiopod crustaceans composed of sexual species and parthenogenetic lineages, and represent an excellent model for studying adaptation and speciation to extreme and heterogeneous hypersaline environments. We tested hypotheses of whether populations from the Tibetan Plateau belong to A. tibetianaAbatzopoulos, Zhang & Sorgeloos,1998and whether a population from Kazakhstan is a new species, using other Asian species of Artemiaas outgroups. We conducted a multitrait phylogenetic study based on the complete mitogenome, mitochondrial (COI, 12S, 16S) and nuclear (microsatellites, ITS1) markers, and a suit of uni- and multivariate morphological traits. Our results led to the discovery of two new species, one from the Tibetan Plateau (Haiyan Lake) in China (Artemia sorgeloosin. sp.) and a second from Kazakhstan (Artemia amatin. sp.). Our analysis demonstrate that A. tibetianaand A. amatin. sp.are monophyletic, whereas A. sorgeloosin. sp., and A. tibetianaare polyphyletic. Evolutionary relationships based on mitochondrial and nSSR markers suggest that A. tibetianamay have arisen from a past hybridization event of a maternal ancestor of A. tibetianawith A. sorgeloosin. sp.or its ancestor. We present the complete mitogenome of A. tibetiana, A. amatin. sp., and A. sorgeloosin. sp.We also provide a novel taxonomic identification key based on morphology, emphasizing the phenotype as a necessary component of the species concept.

Clustered, regularly interspaced, short palindromic repeats (CRISPR) act as an adaptive RNA-mediated immune mechanism in bacteria. They can also be used for identification and evolutionary studies based on polymorphisms within the CRISPR locus. We amplified and analyzed 6 CRISPR loci from 237 Shigellastrains belonging to the 4 species groups, as well as 13 Escherichia colistrains. The CRISPR-associated (cas) gene sequence arrays of these strains were screened and compared. The CRISPR sequences from Shigellawere conserved among subtypes, suggesting that CRISPR may represent a new identification tool for the detection and discrimination of Shigellaspecies. Secondary structure analysis showed a different stem-loop structure at the terminal repeat, suggesting a distinct recognition mechanism in the formation of crRNA. In addition, the presence of “self-target” spacers and polymorphisms within CRISPR in Shigellaindicated a selective pressure for inhibition of this system, which has the potential to damage “self DNA.” Homology analysis of spacers showed that CRISPR might be involved in the regulation of virulence transmission. Phylogenetic analysis based on CRISPR sequences from Shigellaand E. coliindicated that although phenotypic properties maintain convergent evolution, the 4 Shigellaspecies do not represent natural groupings. Surprisingly, comparative analysis of Shigellarepeats with other species provided new evidence for CRISPR horizontal transfer. Our results suggested that CRISPR analysis is applicable for the detection of Shigellaspecies and for investigation of evolutionary relationships.

ABSTRACTA 23-year-old male died of severe pneumonia and respiratory failure in a tertiary hospital in Beijing, and 4 out of 55 close contacts developed fever. Molecular analysis confirmed human adenovirus type 7 (HAdV7) as the causative agent. We highlight the importance of early diagnosis and treatment and proper transmission control of HAdV7.

ABSTRACTA clustered regularly interspaced short palindromic repeat (CRISPR) typing method has recently been developed and used for typing and subtyping of Salmonellaspp., but it is complicated and labor intensive because it has to analyze all spacers in two CRISPR loci. Here, we developed a more convenient and efficient method, namely, CRISPR locus spacer pair typing (CLSPT), which only needs to analyze the two newly incorporated spacers adjoining the leader array in the two CRISPR loci. We analyzed a CRISPR array of 82 strains belonging to 21 Salmonellaserovars isolated from humans in different areas of China by using this new method. We also retrieved the newly incorporated spacers in each CRISPR locus of 537 Salmonellaisolates which have definite serotypes in the Pasteur Institute's CRISPR Database to evaluate this method. Our findings showed that this new CLSPT method presents a high level of consistency (kappa = 0.9872, Matthew's correlation coefficient = 0.9712) with the results of traditional serotyping, and thus, it can also be used to predict serotypes of Salmonellaspp. Moreover, this new method has a considerable discriminatory power (discriminatory index [DI] = 0.8145), comparable to those of multilocus sequence typing (DI = 0.8088) and conventional CRISPR typing (DI = 0.8684). Because CLSPT only costs about $5 to $10 per isolate, it is a much cheaper and more attractive method for subtyping of Salmonellaisolates. In conclusion, this new method will provide considerable advantages over other molecular subtyping methods, and it may become a valuable epidemiologic tool for the surveillance of Salmonellainfections.

ABSTRACTSalmonella entericaserovar Senftenberg is a common nontyphoidal Salmonellaserotype which causes human Salmonellainfections worldwide. In this study, 182 S. Senftenberg isolates, including 17 atypical non-hydrogen sulfide (H2S)-producing isolates, were detected in China from 2005 to 2011. The microbiological and genetic characteristics of the non-H2S-producing and selected H2S-producing isolates were determined by using pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), and clustered regularly interspaced short palindromic repeat (CRISPR) analysis. The phsoperons were amplified and sequenced. The 17 non-H2S-producing and 36 H2S-producing isolates belonged to 7 sequence types (STs), including 3 new STs, ST1751, ST1757, and ST1758. Fourteen of the 17 non-H2S-producing isolates belonged to ST1751 and had very similar PFGE patterns. All 17 non-H2S-producing isolates had a nonsense mutation at position 1621 of phsA. H2S-producing and non-H2S-producing S. Senftenberg isolates were isolated from the same stool sample from three patients; isolates from the same patients displayed the same antimicrobial susceptibility, ST, and PFGE pattern but could be discriminated based on CRISPR spacers. Non-H2S-producing S. Senftenberg isolates belonging to ST1751 have been prevalent in Shanghai, China. It is possible that these emerging organisms will disseminate further, because they are difficult to detect. Thus, we should strengthen the surveillance for the spread of this atypical S. Senftenberg variant.

Elucidating the intrinsic relationship between mitochondrial pH (pHm) fluctuation and lipid droplets (LDs) formation is vital in cell physiology. The development of small-molecular fluorescent probes for discrimination and simultaneous visualization of pHmfluctuation toward LDs has not yet been reported. In this work, utilizing pH-driven polarity-reversible hemicyanine and rhodamine derivatives, a multifunctional fluorescent probe is developed for selectively identifying mitochondria and LDs under specific pH values via dual-emission channels. This rapid-response probe, Hcy-Rh, has two distinct chemical structures under acidic and alkaline circumstances. In acidic conditions, Hcy-Rh exhibits good hydrophilicity that can target mitochondria and display an intense red fluorescence. Conversely, the probe becomes lipophilic under weakly alkaline conditions and targets LDs, showing a strong blue emission. In this manner, Hcy-Rh can selectively label mitochondria and LDs, exhibiting red and blue fluorescence, respectively. Moreover, this ratiometric probe is applied to map pHmchanges in living cells under the stimulus with FCCP, NAC, and H2O2. The interplay of LD–mitochondria under oleic acid treatment and starvation-induced autophagy has been studied using this probe at different pH values. In a word, Hcy-Rh is a potential candidate for further exploring mitochondria–LD interaction mechanisms under pHmfluctuation. Moreover, the polarity-dependent strategy is valuable for designing other functional biological probes in imaging multiple organelles.

Hispanic populations in the US have increased risk of obesity, elevated circulating triglycerides, nonalcoholic fatty liver disease, and diabetes. Our previous studies suggest that ancestry-related differences in the frequency of variants in the fatty acid desaturase (FADS)gene cluster in the context of the modern Western diet can lead to inadequate circulating and tissues levels of n-3 long-chain (LC-; ≥ 20 carbons) polyunsaturated fatty acids (PUFA); these deficiencies in turn have the capacity to increase metabolic disease risk. Specifically, we and others have demonstrated Amerindian (AI)-Ancestry populations have high frequencies of FADSgene variants that may lead to less efficient n-3 LC-PUFA biosynthesis. To test this hypothesis, concentrations of fatty acids, including LC-PUFAs in plasma phospholipids were analyzed in 1,102 Hispanic American participants from Multi-Ethnic Study of Atherosclerosis (MESA) cohort, which represent six Hispanic subgroups based on self-reported region of origin: Central America, South America, Mexico, Cuba, Dominican Republic, and Puerto Rico. These data revealed a striking inverse relationship between genome-wide AI-ancestry and levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Additional analyses revealed that the genotype at FADSSNP rs174537, for which the frequency of the T allele increases with AI-ancestry, could primarily explain the associations. There also was a strong association between the number of T alleles (additive model) at rs174537 and circulating triglycerides (18.5 mg/dL per T allele; P=2.0 x 10-5) as well as an important marker of vascular inflammation sICAM-1 (β=12.7 ng/mL, P=0.02). We also genotyped the FADSSNP, rs174537, in a separate adult Arizona Hispanic cohort (Arizona Insulin Resistance [AIR] registry) and compared the FADSgenotypic frequencies with other racial/ethnic groups. Importantly, the TT genotype associated with limited LC-PUFA biosynthesis ranges from <1% in African-Ancestry populations to 40.2% in AI-Ancestry Hispanics in the AIR Registry, with ~11 % in European-Ancestry populations. These data demonstrate that high AI-ancestry populations have a dramatically higher frequency of the TT genotype versus African and European populations. Importantly similar to MESA, there also was a significant association between the number of T alleles and plasma triglycerides (p = 0.0036; GG = 125±8.18 mg/dl, GT = 135±5.63 mg/dl, TT = 143±5.58 mg/dl) again suggesting the AI-associated TT genotype places this population at higher risk of hypertriglyceridemia. Together, these data reveal that FADSgene*dietary PUFA interactions give rise to n-3 LC-PUFA deficiencies and may enhance metabolic and inflammatory diseases in a large proportion of individuals in AI-Ancestry Hispanic populations.

ABSTRACTHere, we report for the first time a waterborne outbreak of Shigella sonneiin China in 2015. Eleven multidrug-resistant (MDR) S. sonneiisolates were recovered, showing high resistance to azithromycin and third-generation cephalosporins in particular, due to an mph(A)- and blaCTX-M-14-harboring IncB/O/K/Z group transmissible plasmid of 104,285 kb in size. Our study highlights the potential prevalence of the MDR outbreak of S. sonneiin China and its further dissemination worldwide with the development of globalization.