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Objective The COVID‐19 epidemic has caused a significant global social and economic impact since December 2019. The objective of this study was to demonstrate the emergency response of a Chinese blood centre on maintaining both the safety and the sufficiency of blood supply during large, emerging, infectious epidemics. Materials and Methods Early on in the outbreak of COVID‐19, the Chengdu Blood Center developed strategies and implemented a series of measures, including enhanced recruitment efforts, addition of new donation deferral criteria and notification after donation, optimisation of donor experience, development and implementation of a new coronavirus nucleic acid detection technology platform for blood screening and screening all donations for SARS‐CoV‐2 RNA to maximumly protect the safety of blood supply during a time of unclear risk. Results Starting on February 20, the immediate satisfaction rate of blood product orders in Chengdu city's clinical settings reached 100%, and there was no case of blood transfusion infection. Conclusion The recent experience during the outbreak of SARS‐CoV‐2 reminded us that improvement in the areas of national and international collaborative programmes for dealing with blood availability and safety concerns during early stages of a disaster and regional and national mechanisms for timely communication with the general public on behalf of blood services should help to better prepare us for future disasters.

Topological semimetals with high electrical conductivity and suitable carrier density near Fermi level are enticing candidate materials for electrochemical energy storage meriting from their topologically protected surface states. Here we propose the topological semimetal Co 3 Sn 2 S 2 cathode for aqueous Zn ion batteries (AZIBs) showing an obvious discharge plateau approaching 1.5 V. By further introducing a small amount Sn vacancy, an extra pair of redox peaks (1/1.28 V) appears corresponding to the transition of Sn 4+ /Sn 2+ . Sn vacancy leads to more Zn ion built-in channels and active sites, which promotes charge storage kinetics (Zn 2+ diffusion rate and electron transfer rate) and improves Zn-ion storage capability. The increase of active sites contributes to the enhancement of capacitance behavior. The Co 3 Sn 1.8 S 2 cathode achieves a specific energy of 394 Wh kg -1 (capacity of 343.8 mAh g -1 ) at 0.2 A g -1 and specific power greater than 4900 W kg -1 at 5 A g -1 . The battery also retains a capacity of 193.8 mAh g -1 after 2970 cycles at 1 A g -1 . Benefited from better conductivity at lower temperatures of Co 3 Sn 1.8 S 2 and Zn x Co 3 Sn 1.8 S 2 , the prepared quasi-solid Co 3 Sn 1.8 S 2 //Zn battery delivers superior rate capability even at -30 °C (126 mAh g -1 at 0.6 A/g) and excellent cycling stability over 3000 cycles retaining 85% of the initial capacity at -10 °C and 2 A/g. This work provides new insights for designing novel electrode materials by leveraging topologically protected surface states, incorporating vacancies, and in synergy benefit a lot.

Background In China, there is a rising concern on the increasing trends of HIV infections in high-risk groups, who make blood donations that might potentially challenge the blood safety. Analyses on current risk factors for HIV infection among Chinese blood donors are urgently needed for developing effective strategies to defer high-risk donors and to warrant the safety of the blood supply. Study design and methods We recruited 313 HIV-positive and 762 HIV-negative donors from seven study sites in China and evaluated donor demographic characteristics, current medical and behavioral risk factors associated with HIV infection in a case-control survey. Univariable analyses examined the relationship between HIV infection and donor and donation characteristics, medical and behavioral risks, living conditions, and lifestyles. Multivariable logistic regression analyses evaluated the association between selected individual risks and HIV infection. Regression tree analysis was used to select covariates correlated with both HIV infection and individual risks and thus need to be controlled for in logistic regression models. Results Being a man who has sex with men was associated with the highest odds of HIV infection. Not using a condom, having sex with HIV-infected individuals, having sex partners with sexually transmitted diseases (STDs), having more than two concurrent sex partners, or having an STD were all associated with more than five times higher odds of having HIV. Having remunerated sex was associated with a 2.4 increased odds of having HIV infection. Conclusion High-risk sexual behaviors were among the major risks for HIV infection among Chinese blood donors.

Compositions of resin composite exhibit cytotoxicity, especially Triethylene-glycol-dimethacrylate (TEGDMA), yet the underlying mechanisms and its relationship with filler content are poorly understood. Here, specimens of five composites (VITA LC, VITA ZETA, Z350, Filtek P60, and AP-X), containing different filler size and weight, were immersed into culture medium for 72 h. After TEGDMA quantification, the resin composite eluates were used to incubate HGFs. Cellular viability was evaluated. Total reactive oxygen species (ROS) and mitochondrial ROS were detected to assess oxidative stress. Adenosine triphosphate and cytochrome c oxidase (CcO) activity, mitochondrial membrane potential and morphology, mitochondrial biogenesis regulators were analyzed to evaluate mitochondrial functions. Results showed that TEGDMA release negatively correlated to filler size and weight of tested composites. Although cell viability reduction was not significant, total and mitochondrial ROS production showed a positive relationship with the amount of TEGDMA in composite eluates. Furthermore, the expression of mitochondrial biogenesis markers and mitochondrial fusion protein, were markedly elevated in TEGDMA rich eluates, especially in VITA-LC group, shown as elongated mitochondrial morphology and aberrant mitochondrial functions. Overall, TEGDMA could elute easier from those resin composites with less filler content and cause oxidative stress in HGFs via mitochondria dysregulation. These data can be instructive to optimize the synthesis of resin composites from the perspective of biocompatibility. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1132-1142, 2019.

Rechargeable Zn‐based batteries (RZBs) have attracted much attention and been regarded as one of the most promising candidates for next‐generation energy storage featured with high safety, low costs, environmental friendliness, and satisfactory energy density. The aqueous electrolyte system exhibits great potential to power the future wearable electronics. Apart from the achievements of high capacity cathode and stable electrolyte, the anode suffers from problems of dendrite growth, hydrogen evolution, and passivation with limited attention. The dendrite formation strongly restricts the battery lifespan. Therefore, strategies focused on dendrite suppression are carefully categorized and summarized in this review, including crystallographic orientation manipulation, electric field control, ion flux regulation, and mechanical shield. Each strategy and the detailed approaches are critically dissected. Finally, remaining challenges are emphasized in this review, expecting to supply further research with potential directions to fulfill the high performance of the Zn anodes.

Although iron oxide nanoparticles (IRONs) were applied in clinical magnetic resonance imaging in vivo and magnetic tissue engineering in vitro widely, the underlying effects of IRONs on the development of cardiomyocytes especially the intercellular junctions, intercalated discs (IDs), remain an unknown issue. Given the critical role of three-dimensional (3D) engineered cardiac tissues (ECTs) in evaluation of nanoparticles toxicology, it remained necessary to understand the effects of IRONs on IDs assembly of cardiomyocytes in 3D environment. In this study, we first reconstituted collagen/Matrigel based ECTs in vitro and prepared IRONs with 2,3-dimercaptosuccinic acid (DMSA-IRONs). We found that the internalization of DMSA-IRONs by cardiac cells in dose-dependent manner was not associated with the cell distribution in 3D environment by determination of Prussian blue staining and transmission electronic microscopy. Significantly, through determination of western blotting and immunofluorescence of connexin 43, N-cadherin, desmoplakin, and plakoglobin, DMSA-IRONs enhanced the assembly of gap junctions, decreased mechanical junctions (adherens junctions and desmosomes) of cardiac cells but not in dose-dependent manner in ECTs at seventh day. In addition, DMSA-IRONs increased the vesicles secretion of cardiac cells in ECTs apparently compared to control groups. Overall, we conclude that the internalization of DMSA-IRONs by cardiac cells in dose-dependent manner enhanced the assembly of electrochemical junctions and decreased the mechanical related microstructures. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 121-130, 2018.

Weak binding and affinity between the conductive support and iodine species leads to inadequate electron transfer and the shuttle effect. Herein, redox kinetics and duration are significantly boosted by introducing a Nb2 CTX host that is classified as a layered 2D Nb-based MXene. With a facile electrodeposition strategy, initial I- ions are electrically driven to insert in the nanosized interlayers and are electro-oxidized in situ. Linear I2 is firmly confined inside and benefits from the rapid charge supply from the MXene. Consequently, an aqueous Zn battery based on a Zn metal anode and ZnSO4 electrolyte delivers an ultraflat plateau at 1.3 V, which contributes to 84.5% of the capacity and 89.1% of the energy density. Record rate capability (143 mAh g-1 at 18 A g-1 ) and lifespan (23 000) cycles are achieved, which are far superior to those of all reported aqueous MXenes and I2 -metal batteries. Moreover, the low voltage decay rate of 5.6 mV h-1 indicates its superior anti-self-discharge properties. Physicochemical analyses and density functional theory calculations elucidate that the localized electron transfer and trapping effect of the Nb2 CTX MXene host are responsible for enhanced kinetics and suppressed shuttle behavior. This work can be extended to the fabrication of other I2 -metal batteries with long-life-time expectations.

Sulfur cathodes have been under intensive study in various systems, such as Li/S, Na/S, Mg/S, and Al/S batteries. However, to date, Zn/S chemistry has never been reported. The first reliable aqueous Zn/polysulfide system activated by a "liquid film" comprising 4-(3-butyl-1-imidazolio)-1-butanesulfoni ionic liquid (IL) encapsulated within PEDOT:PSS. CF3 SO3- anions in the IL operating as Zn2+ -transfer channels is reported. Moreover, the PEDOT:PSS network retains the IL, which renders Zn2+ -transfer channels and a polysulfide cathode with enhanced structural stability. The Zn/polysulfide system delivers extraordinary capacity of 1148 mAh g-1 and overwhelming energy density of 724.7 Wh kg-1cathode at 0.3 Ag-1 . During the discharging phase, S62- is dominantly reduced by Zn to S2- (S6 → S2- ). During the charging phase, these short chains are oxidized to form long-chain Znx Liy S3-6 . A further optimized high-concentrated salt electrolyte is used to improve the reversibility of the battery, demonstrating an extended lifetime over 1600 cycles at 1 Ag-1 with a capacity retention of 204 mAh g-1 . This facile approach and the superior performance of the developed aqueous Zn/S chemistry provide a new platform for sulfur-based battery and potentially solve the problems of other metal/sulfur batteries.

Pure perovskite K0.5Na0.5NbO3–xSrTiO3 (x = 0.16, 0.17, 0.18, and 0.19) ceramics were prepared by using a solid-state reaction process. The ceramics were optically transparent for visible and near-infrared wavelengths. Then, high tunability (24.1%) and low dielectric loss (0.016) for the x = 0.18 sample indicated the transparent ceramics could be used in tunable devices. The Lorentz-type relation fitting for the temperature dependence of dielectric permittivity showed that these ceramics had a typical relaxor behavior, and the polar nanoregions were related to the tunable dielectric properties. The nonlinear dielectric behavior was further explored by the Johnson model combined with Langevin terms, which revealed that the polar nanoregions contributed to the nonlinear e(E) dependencies with contributions of 12.3%, 11.6%, 5.9%, and 3.6% for x = 0.16, 0.17, 0.18, and 0.19, respectively.

Micellar capillary electrophoresis is optimized for separation of phenylthiohydantoin (PTH) amino acids produced in manual Edman degradation reaction for protein sequencing. There are also two major side-products produced by the Edman degradation reaction: diphenylthiourea and dimethylphenylthiourea. We report the complete separation of 19 PTH amino acids plus the two major side-reaction products in 10 min. Capillary electrophoresis is used to identify the five residues generated by manual Edman degradation sequencing of a pentapeptide.