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Because of its metastable nature, silicon monoxide (SiO) consists of Si nanodomains in an amorphous matrix of SiO

CREC represents a public health threat worldwide, and its colonization precedes or occurs simultaneously with infection; once the colonization rate increases, the infection rate rises sharply. In our hospital, the colonization rate of CREC remained low, and almost all of the CREC isolates detected were ICU acquired.

With the vigorous development of information technology, the textual data of financial news have grown massively, and this ever-rich online news information can influence investors’ decision-making behavior, which affects the stock market. Thus, online news is an important factor affecting market volatility. Quantifying the sentiment of news media and applying it to stock-market prediction has become a popular research topic. In this study, a financial news sentiment lexicon and an auxiliary lexicon applicable to the financial field are constructed, and a sentiment index (SI) is constructed by defining the weight of semantic rules. Then, a comprehensive sentiment index (CSI) is constructed via principal component analysis of the sentiment index and structured stock-market trading data. Finally, these two sentiment indices are added to the generalized autoregressive conditional heteroscedastic (GARCH) and the Long short-term memory (LSTM) models to predict stock returns. The results indicate that the prediction results of LSTM models are better than those of GARCH models. Compared with general-purpose lexicons, the financial lexicons constructed in this study are more stable, and the inclusion of a comprehensive investor sentiment index improves the accuracy of measuring sentiment information. Thus, the proposed lexicons allow more comprehensive measurement of the effects of external sentiment factors on stock-market returns and can improve the prediction effect of stock-return models.

Cefiderocol is a novel siderophore cephalosporin that displays activity against Gram-negative bacteria. To establish cefiderocol susceptibility levels of Acinetobacter baumannii strains from China, we performed susceptibility testing and genomic analyses on 131 clinical isolates. Cefiderocol shows high activity against the strains. The production of PER-1 is the key mechanism of cefiderocol resistance. In silico studies predicted that avibactam and durlobactam could inhibit cefiderocol hydrolysis by PER-1, which was confirmed by determining cefiderocol MICs in combination with inhibitors.

Objectives Community onset urinary tract infections (COUTIs) drew attention recently owing to their increased prevalence and associations with resistant pathogens. The study is aimed at investigating the etiology of COUTIs as well as prevalence and the related risk factors of extended-spectrum β-lactamase (ESBL) in COUTIs in China. Methods The prospective study was performed in nineteen hospitals during November 1, 2017 and August 31, 2019. Non-duplicated isolates from COUTIs were included. The ESBL phenotypic confirmation test was performed and whole genomes were sequenced for all the ESBL-positive bacteria for further analysis. The risk factors for ESBL-producing bacterial infections were analyzed using binary logistic regression. Results A total of 1760 COUTI cases were included in this study. Escherichia coli (1332, 75.7%), Klebsiella pneumoniae (110, 6.3%) and Enterococcus faecalis (52, 3.0%) were the top three common pathogens of COUTIs in China. The overall positive rate of ESBLs in Enterobacterales was 37.2% (562/1512). The age (OR=1.007, P = 0.041), solid malignant tumor (OR=1.668, P = 0.016), prostate diseases (OR=2.035, P = 0.010), history of lithotripsy for urinary calculi (OR=2.009, P = 0.030), history of urological surgery (OR=1.869, P = 0.009) and cephalosporin use within 3 months (OR=1.503, P = 0.025) were independent risk factors for ESBL-producing organisms causing COUTIs. The predominant ESBL types were CTX-Ms, among which CTX-M-14, CTX-M-55 and CTX-M-27 were the most common subtypes. ST131 and ST1193 were the predominant sequence types of ESBL-producing E. coli (ESBL-EC). Most of the tested antimicrobial agents showed significantly higher non-susceptible rates in the ESBL positive group as compared with ESBL-negative group (P Conclusions Enterobacterales, especially E. coli, is the most common pathogen in COUTIs in China and ESBL-producers are highly prevalent. Thus, early prediction depending on risk factors seems to be crucial to determine the appropriate empirical therapy for infections caused by ESBL-producing pathogens.

Owing to the special formation of photopolymerized hydrogels, they can effectively control the formation of hydrogels in space and time. Moreover, the photopolymerized hydrogels have mild formation conditions and biocompatibility; therefore, they can be widely used in tissue engineering. With the development and application of manufacturing technology, photopolymerized hydrogels can be widely used in cell encapsulation, scaffold materials, and other tissue engineering fields through more elaborate manufacturing methods. This review covers the types of photoinitiators, manufacturing technologies for photopolymerized hydrogels as well as the materials used, and a summary of the applications of photopolymerized hydrogels in tissue engineering.

Carbapenem-resistant Acinetobacter baumannii (CRAB), which belonged to global clones 1 (GC1) or 2 (GC2), has been widely reported and become a global threat. However, non-GC1 and non-GC2 CRAB strains are not well-studied, especially for those with rare phenotype. Here, one pyomelanin-producing CRAB strain (A. baumannii DETAB-R21) was isolated from oral swab in the ICU. Antimicrobial susceptibility testing showed it was resistant to carbapenems, ceftazidime, levofloxacin, and ciprofloxacin. DETAB-R21 was ST164

The battery driving mileage on a single charge and convenience of the charging stations affect Electric Vehicle’s (EV) demand. This paper studies the optimal number of charging stations and EV’s price strategy considering different component commonality configurations. Assume the EV manufacturer provides two types of EV and the two EVs have the same battery configuration (battery as a common part) or the same naked vehicle–EV without batteries (naked vehicle as a common part). And the common part could be configured with low or high quality. We discuss four scenarios with different common parts and different quality levels. For each scenario, we present the optimal number of the charging stations and EV prices. Then we compare the optimal solutions and manufacturer’s profits in above four scenarios with numerical simulation and give some managerial insights. Our analysis reveals that (1) consumers’ range anxiety towards battery will affect manufacturer’s product configuration strategy, EVs’ prices and demands. (2) large consumers’ sensitivity towards charging station will corresponding to more charging station, high EV prices and demands. If consumers are very concerned about the charging convenience, high-end electric vehicles need to be launched first, then as customers’ anxiety about charging decreases, the low quality EV could be developed and diffused. (3) the unit product cost reduction caused by the commonality may increase or decrease the EVs’ prices, which depends on the relationship between the demand increment incurred by one more charging station and the cost coefficient of building the charging station. (4) The low quality naked vehicle as common component will increase both the number of the charging stations and the demand and the manufacturer is more likely to obtain high profits. (5) the cost saving coefficient of battery common parts has greater influence on the selection of commonality. When consumers’ range anxiety towards battery is very high, manufacturers should choose low-quality naked vehicles or high-quality battery as common components.

Objectives To characterize a blaOXA-58- and blaNDM-1-containing MDR plasmid from a rare Acinetobacter baumannii lineage and compare it with related plasmids to explore the distribution and evolution of a new plasmid group. Methods A. baumannii DETAB-P2 was isolated from a rectal swab of an intensive care patient. Antibiotic susceptibility was determined using broth microdilution. DETAB-P2 was mated with A. baumannii ATCC 17978 and putative transconjugants were characterized by S1/PFGE and Southern hybridization. WGS was performed on the Illumina and Oxford Nanopore platforms. MLST was performed with the Pasteur and Oxford schemes. Antibiotic resistance genes were identified with ABRicate. Plasmid sequence annotation was performed manually. Complete plasmids in GenBank with the same rep gene were used for comparative analyses. Results A. baumannii DETAB-P2 was ST138 by the Pasteur scheme and a novel Oxford type, ST2209. It transferred blaOXA-58 and blaNDM-1 to ATCC 17978 in the 100 072 bp plasmid pDETAB2 that also carried bleMBL, sul2, aacC2d, tet(39), msr(E)-mph(E) and putative mercury resistance and RND efflux system determinants. pDETAB2 represents a new plasmid type, GR34, and contained 16 pdif sites and several novel dif modules. Only a 10 kbp core sequence is shared amongst pDETAB2 and 18 further GR34 plasmids in GenBank, with diverse accessory regions comprised of various dif modules. Conclusions GR34 plasmids are found in several Acinetobacter species from diverse environments. They display considerable variation in accessory content owing to the presence of pdif sites and an array of dif modules, some of which contain antibiotic resistance genes.

Acinetobacter baumannii is an important pathogen in hospital acquired infections. Although tigecycline currently remains a potent antibiotic for treating infections caused by multidrug resistant A. baumannii (MDRAB) strains, reports of tigecycline resistant isolates have substantially increased. The resistance mechanisms to tigecycline in A. baumannii are far more complicated and diverse than what has been described in the literature so far. Here, we characterize in vitro-selected MDRAB strains obtained by increasing concentrations of tigecycline. We have identified mutations in adeS, rrf and rpoB that result in reduced susceptibility to tigecycline. Using in situ complementation experiments, we confirm that mutations in rrf, rpoB, and two types of mutations in adeS correlate with tigecycline resistance. By Western blot and polysome profile analysis, we demonstrate that the rrf mutation results in decreased expression of RRF, which affects the process of ribosome recycling ultimately leading to increased tigecycline tolerance. A transcriptional analysis shows that the mutated rpoB gene plays a role in regulating the expression of the SAM-dependent methyltransferase (trm) and transcriptional regulators, to confer moderate tigecycline resistance. This study provides direct in vitro evidence that mutations in the adeS, rpoB and rrf are associated with tigecycline resistance in A. baumannii.

Carbapenem-resistant Acinetobacter baumannii (CRAB) is a major public health concern globally. Often studied in the context of hospital outbreaks, little is known about the persistence and evolutionary dynamics of endemic CRAB populations. A three-month prospective observational study was conducted in a 28-bed intensive care unit (ICU) in Hangzhou, China. A total of 3985, 964 and 119 samples were collected from the hospital environment, patients and staff, respectively. CRAB were isolated from 10.75% of collected samples (n = 551) and whole-genome sequenced. The ICU CRAB population was dominated by OXA-23-producing global clone 2 isolates (99.27 % of all isolates) that could be divided into 20 distinct clusters. CRAB was persistently present in the ICU, driven by regular introductions of distinct clusters. The hospital environment was heavily contaminated, with CRAB isolated from bed units on 183/335 (54.63 %) sampling occasions but from patients on only 72/299 (24.08 %) occasions. CRAB was spread to adjacent bed units and rooms and following re-location of patients within the ICU. We also observed that, over the course of this study, three different plasmids had transferred between CRAB strains in the ICU. The epidemiology of CRAB in this setting contrasted with previously described clonal outbreaks in high-income countries, highlighting the importance of environmental CRAB reservoirs in ICU epidemiology. There is an urgent need for targeted infection prevention and control interventions in endemic settings that can address the global threat posed by this against this multidrug-resistant opportunistic pathogen.

Objectives To reconstruct the evolutionary history of the clinical Acinetobacter baumannii XH1056, which lacks the Oxford scheme allele gdhB. Methods Susceptibility testing was performed using broth microdilution and agar dilution. The whole-genome sequence of XH1056 was determined using the Illumina and Oxford Nanopore platforms. MLST was performed using the Pasteur scheme and the Oxford scheme. Antibiotic resistance genes were identified using ABRicate. Results XH1056 was resistant to all antibiotics tested, apart from colistin, tigecycline and eravacycline. MLST using the Pasteur scheme assigned XH1056 to ST256. However, XH1056 could not be typed with the Oxford MLST scheme as gdhB is not present. Comparative analyses revealed that XH1056 contains a 52 933 bp region acquired from a global clone 2 (GC2) isolate, but is otherwise closely related to the ST23 A. baumannii XH858. The acquired region in XH1056 also contains a 34 932 bp resistance island that resembles AbGRI3 and contains the armA, msrE-mphE, sul1, blaPER-1, aadA1, cmlA1, aadA2, blaCARB-2 and ere(B) resistance genes. Comparison of the XH1056 chromosome to that of GC2 isolate XH859 revealed that the island in XH1056 is in the same chromosomal region as that in XH859. As this island is not in the standard AbGRI3 position, it was named AbGRI5. Conclusions XH1056 is a hybrid isolate generated by the acquisition of a chromosomal segment from a GC2 isolate that contains a resistance island in a new location—AbGRI5. As well as generating ST256, it appears likely that a single recombination event is also responsible for the acquisition of AbGRI5 and its associated antibiotic resistance genes.

Background Acinetobacter baumannii is a nosocomial pathogen of critical importance due to the increasing numbers of antibiotic-resistant isolates. Colonies can have a smooth or matt appearance, but also exhibit slimy, mucoid growth, with the latter being increasingly isolated in patients in recent years. Methods We isolated 60 A. baumannii strains from altogether 56 patients and found that all patients were infected by mucoid strains, with four patients having also matt phenotypes in addition to the mucoid ones. The morphology of the colonies and capsules was observed. The antibiotics susceptibilities were tested, and the biofilm formation ability was determined by crystal violet staining. The whole-genome sequencing (WGS) was performed on all the strains, and then the core genome multilocus sequence typing (cgMLST) and drug resistance gene analysis were performed. Finally, a part of isolates were selected to test virulence in a Galleria mellonella model. Results We observed much larger capsules in the mucoid strains compared to the matt isolates. But the mucoid phenotype did not correlate with the amount of biofilm produced by the strain. Almost all mucus-type A. baumannii were multi-drug resistant isolates, containing various antibiotic resistance genes. The main ST types of mucoid-type A.baumannii were ST191 and ST195, of which ST191 isolates were more virulence, while ST195 isolates were weaker. Conclusion The mucoid A. baumannii had resistance to most antibiotics and some strains had high virulence, which should be paid attention in clinical.

Klebsiella pneumoniae carbapenemase (KPC)-producing Pseudomonas aeruginosa (KPC-PA) has been reported sporadically. However, epidemiological and antimicrobial susceptibility data specific for KPC-PA are lacking. We collected 374 carbapenem-resistant P. aeruginosa (CRPA) isolates from seven hospitals in China from June 2016 to February 2019 and identified the blaKPC-2 gene in 40.4% (n = 151/374) of the isolates. Approximately one-half of all KPC-PA isolates (n = 76/151; 50.3%) were resistant to ceftazidime-avibactam (CAZ-AVI). Combining Kraken2 taxonomy identification and Nanopore sequencing, we identified eight plasmid types, five of which carried blaKPC-2, and 13 combination patterns of these plasmid types. In addition, we identified IS26-ΔTn6296 and Tn1403-like–ΔTn6296 as the two mobile genetic elements that mediated blaKPC-2 transmission. blaKPC-2 plasmid curing in 28 strains restored CAZ-AVI susceptibility, suggesting that blaKPC-2 was the mediator of CAZ-AVI resistance. Furthermore, the blaKPC-2 copy number was found to correlate with KPC expression and, therefore, CAZ-AVI resistance. Taken together, our results suggest that KPC-PA is becoming a clinical threat and that using CAZ-AVI to treat this specific pathogen should be done with caution. IMPORTANCE Previous research has reported several cases of KPC-PA strains and three KPC-encoding P. aeruginosa plasmid types in China. However, the prevalence and clinical significance of KPC-PA are not available. In addition, the susceptibility of the strains to CAZ-AVI remains unknown. Samples in this study were collected from seven tertiary hospitals prior to CAZ-AVI clinical approval in China. Therefore, our results represent a retrospective study establishing the baseline efficacy of the novel β-lactam/β-lactamase combination agent for treating KPC-PA infections. The observed correlation between the blaKPC copy number and CAZ-AVI resistance suggests that close monitoring of the susceptibility of the strain during treatment is required. It would also be beneficial to screen for the blaKPC gene in CRPA strains for antimicrobial surveillance purposes.

OXA-23 is the predominant carbapenemase in carbapenem-resistant

Prelithiation promises higher energy density and better cycle performance by providing additional lithium into a Li-ion battery and is therefore gaining increasing attention in industry. However, to achieve extra lithium introduction, additional processes or species need to be introduced, leading to potentially new parasitic reactions. In this work, in operando isothermal microcalorimetry is used to evaluate both the prelithiation process and the associated parasitic reactions. We show with the case of cathode prelithiation using Li2O2 as the prelithiation additive, that while the prelithiation event completed on the first charge, an elevated heat signal extended beyond the first cycle, indicating continued presence of additional parasitic reactions even after the major prelithiation event. The heat signals from such additional parasitic reactions decreased over cycling. After three cycles, similar heat signals from parasitic events were observed for the prelithiation cells and the control cells, indicating stabilization and possibility of no long-term side effects from prelithiation. This first demonstration of in operando isothermal microcalorimetry method for prelithiation application provides valuable insights into heat production in prelithiation cells and offers a first look into prelithiation-associated parasitic reactions and their evolution.

This paper focuses on the impacts of consumer environmental awareness (CEA) and retailer's fairness concerns on environmental quality, wholesale price and retail price of the green product in a one-manufacturer and one-retailer supply chain. The manufacturer produces one green product, and the green product has the environmental quality. This study compares three decision scenarios: decentralized model (Scenario1), retailer is fair-minded and incurs an unfavorable disutility (Scenario 2), retailer is fair-minded and incurs a favorable disutility (Scenario 3). Assume that the manufacturer is the leader, the retailer is the follower, we apply the backward method to solve the Stackelberg game and give the optimal solutions of the environmental qualities, wholesale prices and retail prices. Our analysis reveals that (1) retailer's fairness concerns will not change the environmental quality of the green product, and only affect the wholesale price and retail price; (2) retailer's power in the supply chain and the degree of the fairness concerns jointly determine whether the retailer benefits from the fairness concerns; (3) fairness concerns may change the trend of the retailer's profit with CEA when the retailer is concerned about favorable disutility.

This paper develops a two-echelon green supply chain that consists of one green manufacturer and one retailer. The green manufacturer has both online direct and offline retail channels. Considering manufacturer’s risk attitude and product’s green level, the paper constructs centralized and decentralized game models when the online channel’s demand is uncertain. Furthermore, this paper analyzes the impacts of a set of factors, including consumer environmental awareness (CEA), product green level, and risk attitude on decision-making in the supply chain. Finally, we present numerical examples. The main findings are as follows: the manufacturer and the retailer will benefit from the improvement of CEA; hence, they could invest more to obtain more profits by improving CEA; manufacturer’s risk attitude has a negative impact on the pricing and profits of the supply chain; as such, the members of the supply chain should improve the accuracy of their demand forecast, so as to minimize risks and losses resulting from uncertainty in demand.

Background Acinetobacter baylyi ADP1 is an ideal bacterial strain for high-throughput genetic analysis as the bacterium is naturally transformable. Thus, ADP1 can be used to investigate DNA mismatch repair, a mechanism for repairing mismatched bases. We used the mutS deletion mutant (XH439) and mutL deletion mutant (XH440), and constructed a mutS mutL double deletion mutant (XH441) to investigate the role of the mismatch repair system in A. baylyi. Results We determined the survival rates after UV irradiation and measured the mutation frequencies, rates and spectra of wild-type ADP1 and mutSL mutant via rifampin resistance assay (RifR assay) and experimental evolution. In addition, transformation efficiencies of genomic DNA in ADP1 and its three mutants were determined. Lastly, the relative growth rates of the wild type strain, three constructed deletion mutants, as well as the rifampin resistant mutants obtained from RifR assays, were measured. All three mutants had higher survival rates after UV irradiation than wild type, especially the double deletion mutant. Three mutants showed higher mutation frequencies than ADP1 and favored transition mutations in RifR assay. All three mutants showed increased mutation rates in the experimental evolution. However, only XH439 and XH441 had higher mutation rates than the wild type strain in RifR assay. XH441 showed higher transformation efficiency than XH438 when donor DNA harbored transition mutations. All three mutants showed higher growth rates than wild-type, and these four strains displayed higher growth rates than almost all their rpoB mutants. The growth rate results showed different amino acid mutations in rpoB resulted in different extents of reduction in the fitness of rifampin resistant mutants. However, the fitness cost brought by the same mutation did not vary with strain background. Conclusions We demonstrated that inactivation of both mutS and mutL increased the mutation rates and frequencies in A. baylyi, which would contribute to the evolution and acquirement of rifampicin resistance. The mutS deletion is also implicated in increased mutation rates and frequencies, suggesting that MutL may be activated even in the absence of mutS. The correlation between fitness cost and rifampin resistance mutations in A. baylyi is firstly established.

Additional file 1 : Table S1. Predicted mutations in A. baylyi ADP1Â from the WGS experiments.

An epoxy group was successfully attached to the surface of silicon nanoparticle (SiNPs) via a silanization reaction between silanol-enriched SiNPs and functional silanes. The epoxy-functionalized SiNPs showed a much improved cell performance compared with the pristine SiNPs because of the increased stability with electrolyte and the formation of a covalent bond between the epoxy group and the polyacrylic acid binder. Furthermore, the anode laminate made from epoxy-SiNPs showed much enhanced adhesion strength. Post-test analysis shed light on how the epoxy-functional group affects the physical and electrochemical properties of the SiNP anode.

The application of lithium-ion batteries in electric vehicles calls for decreased cost, increased energy density, increased power density, as well as low-temperature and fast-charging capability. In regard to fast charging, it is generally understood that it is the kinetic overpotential at the graphite anode that limits the cycling rate in modern commercial battery formulations. In this work, we study the fast-charging capabilities of a series of doped and un-doped graphite samples from a commercial supplier, as part of a materials validation effort at Argonne National Laboratory. We combine materials characterization data from the raw samples with electrochemical characterization of graphite laminate electrodes in both half and full cell configurations to explore the causes of differences in rate performance and its impact on cycle life. Acknowledgement: We gratefully acknowledge the support from the U.S. Department of Energy’s (DOE) office of Energy Efficiency & Renewable Energy (EERE) Vehicle Technologies Office. This work is conducted under the Cell Analysis, Modeling, and Prototyping (CAMP) Facility at Argonne National Laboratory, a U.S. Department of Energy Office of Science Laboratory operated under Contract No. DE-AC02-06CH11357.

Poly(acrylic acid) (PAA) based binders have been widely used for the high capacity silicon anodes of lithium-ion batteries. While numerous promising progress has been reported, there is no general guideline for choosing the right PAA binders for optimized cycling performance. In this report, aiming to optimize the cycling performance of the Si/graphite composite anodes (15 wt% Si), we systemically investigated a series of PAA binders by validating their molecular weights (MWs) and correlating them to the cycling performance of the anodes fabricated with such binders. The gel permeation chromatography (GPC) was used to validate the MWs of six PAA binders (PAA1 to PAA6). Those binders then underwent a series of characterizations, including rheology study, half-cell cycling, scanning electron microscope (SEM), and Fourier-transform infrared spectroscopy (FTIR). It is observed that the MWs of PAA binders not only affected the viscosities of the binder solutions but also impacted the cycling performance, possibly due to the cohesion changes. A range of 24–150 kDa is found to be optimal for minimizing the rate and extent of capacity fade and maintaining the cohesion in the electrode matrix despite the dramatic volumetric changes due to Si alloying.

The capacity fading phenomenon of high energy lithium-ion batteries (LIBs) using a silicon monoxide (SiO) anode and a nickel-rich transition metal oxide cathode were investigated during life test. The capacity loss of this electrode couple was found to increase not only with cycles (cycle life), but also with rest time (calendar life). The capacity fading rate for this type of LIB using SiO as the anode was found to be time-dependent, rather than cycle-count-dependent. Further detailed investigation revealed that the capacity loss of this electrode couple during rest was caused by the parasitic reactions on the anode, which consumed the lithium ions and lead to less cyclable lithium in the battery system.

Compared to the graphite anode, Si and SiOx-containing anodes usually have a larger initial capacity loss (ICL) due to more parasitic reactions. The higher ICL of the anode can cause significant Li inventory loss in a full cell, leading to a compromised energy density. As one way to mitigate such Li inventory loss, Li2O2 can be used as the cathode prelithiation additive to provide additional lithium. However, an additional catalyst is usually needed to lower its decomposition potential. In this work, we investigate the use of Li2O2 as the cathode prelithiation additive without the addition of a catalyst. Li2O2 decomposition is first demonstrated in coin half-cells with a calculated capacity of 1180 mAh g−1 obtained from Li2O2 decomposition. We then further demonstrate successful Li2O2 decomposition in single-layer pouch (SLP) full cells and evaluate the initial electrochemical performance. Despite its moisture sensitivity, Li2O2 showed reasonable compatibility with dry-room handling. After dry-room handling, Li2O2 decomposition was observed with an onset potential of 4.29 V vs SiOx anode in SLP cells. With Li2O2 addition, the utilization of the Li inventory from cathode active material was improved by 12.9%, and discharge DCR was reduced by 7% while the cells still delivered similar cell capacities. Cycle performance is not evaluated in this paper due to the high cutoff voltage used, but the factors affecting the cycle performance are discussed. Strategies to further improve the practical use of Li2O2 are also discussed.

In this study, silicon nanoparticles are oxidized in a controlled manner to obtain different thicknesses of SiO2 layers. Their stability in aqueous slurries as well as the effect of oxide layer thickness on the electrochemical performance of the silicon anodes is evaluated. Our results show that slightly increasing the oxide layer of silicon nanoparticles significantly improves the stability of the nanoparticles in aqueous slurries and does not compromise the initial electrochemical performance of the electrodes. A careful comparison of the rate and cycle performance between 400 °C treated Si nanoparticles and pristine Si nanoparticles shows that by treating the silicon nanoparticles in air for slightly increasing the oxide layer, improvement in both rate and cycle performance can be achieved.

Recent studies have shown that optically excited diamond can act as a solid-state source of solvated electrons in aqueous media, leading to novel reduction reactions such as the one-electron activation pathway (CO 2 + e − → − CO 2 − , E° = − 1.9 V vs SHE) for reduction of CO 2 to CO. However, an understanding of the valence band reactions is also essential, especially since CO can also be produced in the absence of CO 2 by oxidation of diamond via C + H 2 O → CO + 2H + + 2e − (E° = 0.52 V). Here, we demonstrate that H-terminated diamond nanoparticles with a median diameter of 125 nm can initiate selective photochemical reduction of CO 2 to CO, and that argon-purged control samples show no production of CO production in the absence of intentional CO 2 reactant as long as a sacrificial electron donor (here, Na 2 SO 3 ) is present. However, in the absence of an electron donor clear signs of diamond oxidation and aggregation are observed. In contrast, experiments with detonation nanodiamond show rapid changes upon illumination consistent with oxidation of the samples. Our results indicate that crystallinity and absence of high-energy defect sites is important to stability of nanodiamond-based photocatalysts.

The study considers a retailer that sells a short-life-cycle product and uses the online channel as a supplement to its traditional channel. The inventory of the product is finite. The sales season is split into two periods: the premium period and the discount period. The study investigates how the retailer coordinates two channels with proper pricing strategies and channel mix. We introduce a new strategy to address channel conflict, in which two channels are introduced at different periods and the retailer employs different pricing mechanisms for two channels. We also explore the effects of return rate, service difference, and the retailer's risk attitude. Numerical examples are used to compare the solutions with other channel selection and pricing strategies, and further investigate the situations when some assumptions are not satisfied. The study suggests that the benefits of introducing the online channel are contingent on the potential demand of the online channel, the inventory level of the product, and the time of introducing the online channel. The retailer could adjust price difference between two channels to reduce channel conflict. Its risk attitude also influences the pricing strategies and sales revenue. Managerial implications of the study are discussed.

Acinetobacter baumannii is an important Gram-negative pathogen in hospital-related infections. However, treatment options for A. baumannii infections have become limited due to multidrug resistance. Bacterial virulence is often associated with capsule genes found in the K locus, many of which are essential for biosynthesis of the bacterial envelope. However, the roles of other genes in the K locus remain largely unknown. From an in vitro evolution experiment, we obtained an isolate of the virulent and multidrug-resistant A. baumannii strain MDR-ZJ06, called MDR-ZJ06M, which has an insertion by the ISAba16 transposon in gnaA (encoding UDP-N-acetylglucosamine C-6 dehydrogenase), a gene found in the K locus. The isolate showed an increased resistance toward tigecycline, whereas the MIC decreased in the case of carbapenems, cephalosporins, colistin, and minocycline. By using knockout and complementation experiments, we demonstrated that gnaA is important for the synthesis of lipooligosaccharide and capsular polysaccharide and that disruption of the gene affects the morphology, drug susceptibility, and virulence of the pathogen.