All-temperature area battery application mechanism, performance, and strategies.

Further applications of electric vehicles (EVs) and energy storage stations are limited because of the thermal sensitivity, volatility, and poor durability of lithium-ion batteries (LIBs), especially given the urgent requirements for all-climate utilization and fast charging. This study comprehensively reviews the thermal characteristics and management of LIBs in an all-temperature area based on the performance, mechanism, and thermal management strategy levels. At the performance level, the external features of the batteries were analyzed and compared in cold and hot environments. At the mechanism level, the heat generation principles and thermal features of LIBs under different temperature conditions were summarized from the perspectives of thermal and electrothermal mechanisms. At the strategy level, to maintain the temperature/thermal consistency and prevent poor subzero temperature performance and local/global overheating, conventional and novel battery thermal management systems (BTMSs) are discussed from the perspective of temperature control, thermal consistency, and power cost. Moreover, future countermeasures to enhance the performance of all-climate areas at the material, cell, and system levels are discussed. This study provides insights and methodologies to guarantee the performance and safety of LIBs used in EVs and energy storage stations.

Data-driven capacity estimation of commercial lithium-ion batteries from voltage relaxation.

Accurate capacity estimation is crucial for the reliable and safe operation of lithium-ion batteries. In particular, exploiting the relaxation voltage curve features could enable battery capacity estimation without additional cycling information. Here, we report the study of three datasets comprising 130 commercial lithium-ion cells cycled under various conditions to evaluate the capacity estimation approach. One dataset is collected for model building from batteries with LiNi0.86Co0.11Al0.03O2-based positive electrodes. The other two datasets, used for validation, are obtained from batteries with LiNi0.83Co0.11Mn0.07O2-based positive electrodes and batteries with the blend of Li(NiCoMn)O2 - Li(NiCoAl)O2 positive electrodes. Base models that use machine learning methods are employed to estimate the battery capacity using features derived from the relaxation voltage profiles. The best model achieves a root-mean-square error of 1.1% for the dataset used for the model building. A transfer learning model is then developed by adding a featured linear transformation to the base model. This extended model achieves a root-mean-square error of less than 1.7% on the datasets used for the model validation, indicating the successful applicability of the capacity estimation approach utilizing cell voltage relaxation.

Investigating the critical characteristics of thermal runaway process for LiFePO4/graphite batteries by a ceased segmented method.

Lithium-ion batteries (LIBs) are widely used as the energy carrier in our daily life. However, the higher energy density of LIBs results in poor safety performance. Thermal runaway (TR) is the critical problem which hinders the further application of LIBs. Clarifying the mechanism of TR evolution is beneficial to safer cell design and safety management. In this paper, liquid nitrogen spray is proved to be an effective way to stop the violent reaction of LIBs during the TR process. Based on extended-volume accelerating rate calorimetry, the liquid nitrogen ceasing combined with non-atmospheric exposure analysis is used to investigate the TR evolution about LiFePO4/graphite batteries at critical temperature. Specifically, the geometrical shape, voltage, and impedance change are monitored during the TR process on the cell level. The morphologies/constitution of electrodes and separators are presented on the component level. Utilizing the gas analysis, the failure mechanism of the prismatic LiFePO4/graphite battery is studied comprehensively.

Comprehensive Investigation of a Slight Overcharge on Degradation and Thermal Runaway Behavior of Lithium-Ion Batteries.

Overcharge is a hazardous abuse condition that has dominant influences on cell performance and safety. This work, for the first time, comprehensively investigates the impact of different overcharge degrees on degradation and thermal runaway behavior of lithium-ion batteries. The results indicate that single overcharge has little influence on cell capacity, while it severely degrades thermal stability. Degradation mechanisms are investigated by utilizing the incremental capacity-differential voltage and relaxation voltage analyses. During the slight overcharge process, the conductivity loss and the loss of lithium inventory always occur; the loss of active material starts happening only when the cell is overcharged to a certain degree. Lithium plating is the major cause for the loss of lithium inventory, and an interesting phenomenon that the arrival time of the dV/dt peak decreases linearly with the increase of the overcharge degree is found. The cells with different degrees of overcharge exhibit a similar behavior during adiabatic thermal runaway. Meanwhile, the relationship between sudden voltage drop and thermal runaway is further established. More importantly, the characteristic temperature of thermal runaway, especially the self-heating temperature (T1), decreases severely along with overcharging, which means that a slight overcharge severely decreases the cell thermal stability. Further, post-mortem analysis is conducted to investigate the degradation mechanisms. The mechanism of the side reactions caused by a slight overcharge on the degradation performance and thermal runaway characteristics is revealed.

Hospital biosecurity capacitation: Analysis and recommendations for the prevention and control of COVID-19.

The outbreak of the coronavirus disease 2019 (COVID-19) in December 2019 highlighted several concerns regarding hospital biosafety capacitation in the People's Republic of China, although the epidemic is now under control. This study examined the primary problems related to hospital biosecurity, including the absence of a hospital emergency system, inadequate management and control of nosocomial infection, limited hospital laboratory capacity, and poor hospital admission capacity. Accordingly, this study puts forward the following countermeasures and suggestions for hospitals to deal with future biosecurity events, such as a major epidemic: first, biosecurity management systems and emergency response mechanisms in hospitals need to be set up; second, the investment and guarantee mechanisms for hospital biosecurity construction should be improved; third, the capacity building of biosecurity incident management requires special attention in general hospitals; and finally, comprehensive plans need to be developed for the integrated construction of medical treatment and prevention facilities through disease-control systems.

Cross-Species Bioinspired Anisotropic Surfaces for Active Droplet Transportation Driven by Unidirectional Microcolumn Waves.

Natural evolution has endowed diverse species with distinct geometric micro/nanostructures exhibiting admirable functions. Examples include anisotropic microgrooves/microstripes on the rice leaf surface for passive liquid directional rolling, and motile microcilia widely existed in mammals' body for active matter transportation through in situ oscillation. Till now, bionic studies have been extensively performed by imitating a single specific biologic functional system. However, bionic fabrication of devices integrating multispecies architectures is rarely reported, which may sparkle more fascinating functionalities beyond natural findings. Here, a cross-species design strategy is adopted by combining the anisotropic wettability of the rice leaf surface and the directional transportation characteristics of motile cilia. High-aspect-ratio magnetically responsive microcolumn array (HAR-MRMA) is prepared for active droplet transportation. It is found that just like the motile microcilia, the unidirectional waves are formed by the real-time reconstruction of the microcolumn array under the moving magnetic field, enabling droplet (1-6 µL) to transport along the predetermined anisotropic orbit. Meanwhile, on-demand droplet horizontal transportation on the inclined plane can be realized by the rice leaf-like anisotropic surface, showcasing active nongravity-driven droplet transportation capability of the HAR-MRMA. The directional lossless transportation of droplet holds great potential in the fields of microfluidics, chemical microreaction, and intelligent droplet control system.

Adjusted Intensive Care Infection Score (ICISΔ)-A new approach for prediction of ascitic fluid infection in patients with cirrhosis.

BACKGROUND: Early and accurate diagnosis is the key to improving survival in cirrhotic patients with ascitic fluid infection. AIMS: To investigate the usefulness of adjusted Intensive Care Infection Score (ICISΔ) for diagnosis of ascites infection in cirrhotic patients. METHODS: Cirrhotic patients with ascites (n = 125) were enrolled, and the efficacy of ICIS and ICISΔ for predicting ascites infection was evaluated. ICISΔ was created by using the weighted variation of each ICIS parameter. RESULTS: The area under the curves (AUCs) of ICIS for the diagnosis of ascites infection were 0.90 (95% CI: 0.84-0.95), 0.85 (95% CI: 0.79-0.90), and 0.87 (95% CI: 0.81-0.93), for SBP, culture-negative SBP, and combined SBP/culture-negative SBP, respectively. ICIS was optimized and diagnostic accuracy was obviously improved. ICISΔ had high AUCs of 0.99 (95% CI: 0.93-1.00) for SBP, 0.98 (95% CI: 0.83-1.00) for culture-negative SBP, and 0.98 (95% CI: 0.94-1.00) for the combination group. The optimal cutoff was identified as ICISΔ > 2, which had >97.8% sensitivity and 100% specificity for diagnosis of both SBP and culture-negative SBP. The ICISΔ had significantly higher AUCs than PCT and CPR in both groups (P = 0.002-0.008). ICISΔ kinetics could differentiate between SBP and culture-negative SBP patients. From sterile ascites, through culture-negative SBP to SBP, three ICISΔ parameters showed an increasing trend. CONCLUSIONS: ICIS and ICISΔ are simple, rapid, accurate and cost-effective methods for the diagnosis of ascites infection in cirrhotic patients.

Antimicrobial Resistance and Molecular Investigation of H2S-Negative Salmonella enterica subsp. enterica serovar Choleraesuis Isolates in China.

Salmonella enterica subsp. enterica serovar Choleraesuis is a highly invasive pathogen of swine that frequently causes serious outbreaks, in particular in Asia, and can also cause severe invasive disease in humans. In this study, 21 S. Choleraesuis isolates, detected from 21 patients with diarrhea in China between 2010 and 2011, were found to include 19 H2S-negative S. Choleraesuis isolates and two H2S-positive isolates. This is the first report of H2S-negative S. Choleraesuis isolated from humans. The majority of H2S-negative isolates exhibited high resistance to ampicillin, chloramphenicol, gentamicin, tetracycline, ticarcillin, and trimethoprim-sulfamethoxazole, but only six isolates were resistant to norfloxacin. In contrast, all of the isolates were sensitive to cephalosporins. Fifteen isolates were found to be multidrug resistant. In norfloxacin-resistant isolates, we detected mutations in the gyrA and parC genes and identified two new mutations in the parC gene. Pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), and clustered regularly interspaced short palindromic repeat (CRISPR) analysis were employed to investigate the genetic relatedness of H2S-negative and H2S-positive S. Choleraesuis isolates. PFGE revealed two groups, with all 19 H2S-negative S. Choleraesuis isolates belonging to Group I and H2S-positive isolates belonging to Group II. By MLST analysis, the H2S-negative isolates were all found to belong to ST68 and H2S-positive isolates belong to ST145. By CRISPR analysis, no significant differences in CRISPR 1 were detected; however, one H2S-negative isolate was found to contain three new spacers in CRISPR 2. All 19 H2S-negative isolates also possessed a frame-shift mutation at position 760 of phsA gene compared with H2S-positive isolates, which may be responsible for the H2S-negative phenotype. Moreover, the 19 H2S-negative isolates have similar PFGE patterns and same mutation site in the phsA gene, these results indicated that these H2S-negative isolates may have been prevalent in China. These findings suggested that surveillance should be increased of H2S-negative S. Choleraesuis in China.

hfq regulates acid tolerance and virulence by responding to acid stress in Shigella flexneri.

Shigella flexneri is an important etiological agent of bacillary dysentery in developing countries. The Hfq protein is thought to play a major regulatory role in various cellular processes in this organism. However, the roles of Hfq in stress tolerance and virulence in S. flexneri in response to environmental stress have not been fully studied. In this study, hfq was highly expressed when S. flexneri was exposed to low pH. Growth retardation was observed in the hfq deletion mutant at pH values ranging from 5.0 to 7.0 and the survival rate of the mutant strain was reduced by 60% in acidic conditions (pH 3.0) compared with the wild-type strain. Additionally, competitive invasion assays in HeLa cells and lung invasion assays showed that the virulence of the hfq deletion mutant was significantly decreased. An evaluation of the mechanism revealed that, along with the expression of the Type III secretion system genes, acid resistance genes were also increased with acid stress. Interestingly, a statistically strong linear correlation was observed between the expression of hfq and Type III secretion system genes, as well as between hfq and acid resistance genes, under various pH conditions. In this study, we provide evidence that Hfq regulates genes related to acid resistance for survival under acid stress and controls virulence through the positive regulation of Type III secretion systems. Importantly, we propose that hfq is a key factor in maximal adaptation to host acid stress during infection, regulating acid stress tolerance and virulence in response to acid stress in S. flexneri.

Electrochemical DNA Biosensor Based on a Tetrahedral Nanostructure Probe for the Detection of Avian Influenza A (H7N9) Virus.

A DNA tetrahedral nanostructure-based electrochemical biosensor was developed to detect avian influenza A (H7N9) virus through recognizing a fragment of the hemagglutinin gene sequence. The DNA tetrahedral probe was immobilized onto a gold electrode surface based on self-assembly between three thiolated nucleotide sequences and a longer nucleotide sequence containing complementary DNA to hybridize with the target single-stranded (ss)DNA. The captured target sequence was hybridized with a biotinylated-ssDNA oligonucleotide as a detection probe, and then avidin-horseradish peroxidase was introduced to produce an amperometric signal through the interaction with 3,3',5,5'-tetramethylbenzidine substrate. The target ssDNA was obtained by asymmetric polymerase chain reaction (PCR) of the cDNA template, reversely transcribed from the viral lysate of influenza A (H7N9) virus in throat swabs. The results showed that this electrochemical biosensor could specifically recognize the target DNA fragment of influenza A (H7N9) virus from other types of influenza viruses, such as influenza A (H1N1) and (H3N2) viruses, and even from single-base mismatches of oligonucleotides. Its detection limit could reach a magnitude of 100 fM for target nucleotide sequences. Moreover, the cycle number of the asymmetric PCR could be reduced below three with the electrochemical biosensor still distinguishing the target sequence from the negative control. To the best of our knowledge, this is the first report of the detection of target DNA from clinical samples using a tetrahedral DNA probe functionalized electrochemical biosensor. It displays that the DNA tetrahedra has a great potential application as a probe of the electrochemical biosensor to detect avian influenza A (H7N9) virus and other pathogens at the gene level, which will potentially aid the prevention and control of the disease caused by such pathogens.

Effect of different nitrogenous nutrients on the cadmium hyperaccumulation efficiency of Rorippa globosa (Turcz.) Thell.

This experiment was used to explore whether the 11 nitrogenous nutrients affect the hyperaccumulation of Rorippa globosa (Turcz.) Thell. to Cd. Pot culture experiments using soil spiked with Cd as CdCl2·2.5H2O and 11 nitrogen-containing chemicals were conducted to determine the efficiency of the accumulation of Cd by R. globosa. Application of all 11 nitrogenous nutrients significantly (p < 0.05) enhanced Cd accumulation by R. globosa (Turcz.) Thell. Two major modes of Cd accumulation were observed: (i) through increase of biomass yield without reduction of Cd uptake and (ii) through increase of Cd uptake efficiency in parallel with increase of biomass yield. Bicarbonate > phosphate > chloride compounds of NH4 enhanced the biomass yield to the greatest extent, while oxalate > nitrate > chloride > and bicarbonate caused a significant increase of Cd uptake by R. globosa. Competition between N and Cd translocation caused either significant reduction of Cd translocation factor or decrease of biomass yield. Of studied nutrients, ammonium bicarbonate NH4HCO3 and ammonium chloride NH4Cl exerted the best joint effect of these two processes on the efficiency of R. globosa as a Cd hyperaccumulator. Application of these chemicals caused increase of Cd concentrations in roots of R. globosa by 35.1 and 41.1 %, and in shoots by 13.9 and 56.4 %, while biomasses of roots increased by 5.8- and 3.8-fold and in shoots by 7.4-fold, and 6.4-fold, respectively, compared to the control. As a result, accumulated load (µg pot(-1)) of Cd in roots increased by 8.2- and 5.8-fold and in shoots by 8.6- and 10.6-fold in both pots. Consequently, chemicals (NH4HCO3 and NH4Cl) that enhanced both Cd enrichment and biomass yield had the greatest effect on the bioaccumulation capacity of R. globosa.

[Dynamic analysis of the lymphocyte subsets in HCV children with different genotypes during treatment].

OBJECTIVE: To discuss the changes of lymphocyte subsets in HCV children with different genotypes during treatment with pegylated interferon alfa-2b and ribavirin. METHODS: The genotype of 45 HCV infected children were identified by real time PCR. The lymphocyte subsets were dynamically detected by BD FACSCalibur flow cytometer with four color MultiTEST IMK Kit during the treatment. RESULTS: For the children with 1b genotype, after 24 weeks, the CD4+ T cells were higher than pre-treatment (P < 0.05). For the children with 2a genotype, after 12 weeks and after 24 weeks, the CD3+ T cells and CD4+ T cells significantly increased while the NK cells decreased than pre-treatment (P < 0.05). CONCLUSIONS: The lymphocyte subsets of HCV children with 2a genotype were different from 1b genotype during trentment with pegylated interferon alfa-2b and ribavirin.

Identification of rice cultivar with exclusive characteristic to Cd using a field-polluted soil and its foreground application.

Using low-accumulative plant, especially excluder crop, to safely produce food is one of the very important technologies of phytoremediation, which is practical to safe production and long-term remediation of heavy metal-contaminated soil. A pot experiment using field cadmium (Cd)-contaminated soil (Cd concentration was 0.75 mg kg(-1)) was conducted to compare Cd accumulation differences among 39 normal rice cultivars (Japonica) in Shenyang region of China for food safety and high grain yield aim. The results showed that brown grain Cd concentration in 12 rice cultivars of a total of 39 tested cultivars was lower than 0.2 mg kg(-1) (Agricultural Trade Standard of Nonpollution Food for Rice of China, NY 5115-2008). In these 12 cultivars, Cd enrichment factors (Cd concentration ratio in shoot to that in soil) of nine cultivars were lower than 1. Likewise, Cd translocation factors (Cd concentration ratio in shoot to that in root) of eight cultivars were lower than the 0.28 average. Furthermore, grain yield per pot of seven cultivars were higher than the average 18.4 g pot(-1). Four cultivars, i.e., Shendao 5, Tianfu 1, Fuhe 90, and Yanfeng 47 showed Cd-exclusive characteristic and better foreground application.

Tolerant mechanisms of Rorippa globosa (Turcz.) Thell. hyperaccumulating Cd explored from root morphology.

Hoagland solution was used to determine the root morphology properties of Rorippa globosa (Turcz.) Thell. and Rorippa palustris (Leyss.) Bess. Under the conditions of Cd spiked at 2.5 and 5 mg kg(-1), R. globosa showed all hyperaccumulative characteristics and was a Cd-hyperaccumulator. In contrast, R. palustris was a non-hyperaccumulator. The total root lengths, total root surface areas and total root volumes of R. globosa were not significantly decreased (p<0.05) compared to the control when 2.5 and 5 mg kg(-1) of Cd added. However, these 3 indexes of R. palustris were all significantly decreased (p<0.05) when 2.5, 5, 10, 20 and 40 mg kg(-1) Cd added compared its control. The average root diameters of R. palustris and R. globosa were not affected by Cd. These results showed that root morphology might be a factor of plant with strong tolerance to Cd.