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A novel 3.3 V copper-lithium battery using a copper foil as the cathode is a potential candidate for next-generation energy storage system due to its simple manufacturing process. However, the cross-over of copper ions from the cathode to the anode limits the reversibility of the battery. Herein, we suppress self-discharge and migration of copper ions in the cell using a commercial polypropylene separator with a coating of polyacrylic acid (PAA), a chelating polymer. Fourier transform infrared spectroscopy confirms that the PAA layer traps the copper ions and prevents them from passing through. The addition of barium titanate nanoparticles into the PAA layer further enhances ionic transfer through the separator and reduces polarization of the cell at high current rates during charge and discharge. The use of a chelating agent with an inorganic filler as a coating layer on the separator is a cost-effective way to improve reversibility and round-trip efficiency of copper-lithium batteries.

Combining metal to form metal phosphide is a promising strategy to address the fast capacity decay of P rooted from its low electronic conductivity and large volume changes upon cycling. Cu3P, which possesses a high theoretical gravimetric and volumetric capacity of 363 mAh·g−1 and 1028 Ah·L−1 and reasonable volume expansion of 156% during sodiation, was investigated as anode material in SIBs. Hollow-structured Cu3P electrode delivers an initial de-sodiation capacity of ~ 159.0 mAh·g−1 with high capacity retention of ~ 85.1% over 50 cycles at 0.2C rate and exhibits good rate performance, retaining 70% of the capacity when the current density increases from 0.2C to 1.6C. A 3 V-class full cell consisting of P2-Na2/3Ni1/3Mn1/2Ti1/6O2 cathode and Cu3P anode was also assembled, which could achieve an energy density of ~ 189.3 Wh·kg−1 (based on the mass of both electrode materials) and average discharge voltage of ~ 2.91 V when cycled in 1.0–4.3 V at 0.1C. Facile synthesis of hollow Cu3P as a good anode candidate for sodium-ion batteries

According to official data, up to 40 million cases of infectious diseases are registered in Russia annually, half of them in children. Vaccination can significantly reduce the incidence of various infectious diseases, such as diphtheria, measles, tetanus, poliomyelitis, etc. However, development of new safe and effective vaccine preparations is still relevant. One of the approaches to their development is vaccines based on various viral vectors, including recombinant human adenoviruses. Such vaccines have shown their safety and effectiveness in preclinical and clinical trials, including trials in the Russian Federation.

The results of the predictive analytical studies on Covid-19 incidence dynamics in Moscow, taking into account different changes in epidemic prevention measures, including vaccination coverage of the population, are presented.Research Objective. Using the new epidemiological model for analysis and prediction of the Covid-19 incidence dynamics in Moscow and outlining main strategies in implementing epidemic prevention measures (EPMs), including vaccination in 2020/2021.Materials and methods. The epidemiological model is based on the Russian approach to mathematical modeling of epidemics, known as Epiddynamics. The medium-term forecasting incorporated probable scenarios of epidemic development with different EPMs (isolation of the infected and contacts, breaking the transmission chains), including different rates of vaccination coverage in Moscow.Results and discussion. The computational simulations demonstrated that the incidence rate is likely to increase with scaling down EPMs and zero vaccination coverage. At the same time, the daily incidence rate depends on the degree of EPMs reduction and basically does not depend on the time when the reduction begins. With scaled-down EPMs, vaccination can decrease the incidence, though its effectiveness will depend on the time of its commencement, coverage and rate.Conclusion. The computational simulations showed that the vaccination will be efficient for prevention of new surges in COVID-19 cases only if the other EPMs (isolation of the infected and contacts, breaking the transmission chains) are still in place until the vaccination coverage reaches about 2 million people. Ideally, the measures aimed at isolation and breaking of transmission chains should be continued until the total vaccination coverage reaches 4 million people, after which the restrictive measures can be scaled down significantly. With vaccination coverage of 50% of the population of Moscow, the restrictive measures can be completely discontinued.

An excessive inflammatory response to SARS-CoV-2 is thought to be a major cause of disease severity and mortality in patients with COVID-19. Longitudinal analysis of cytokine release can expand our understanding of the initial stages of disease development and help to identify early markers serving as predictors of disease severity. In this study, we performed a comprehensive analysis of 46 cytokines (including chemokines and growth factors) in the peripheral blood of a large cohort of COVID-19 patients (n=444). The patients were classified into five severity groups. Longitudinal analysis of all patients revealed two groups of cytokines, characterizing the “early” and “late” stages of the disease course and the switch between type 1 and type 2 immunity. We found significantly increased levels of cytokines associated with different severities of COVID-19, and levels of some cytokines were significantly higher during the first three days from symptom onset (DfSO) in patients who eventually required intensive care unit (ICU) therapy. Additionally, we identified nine cytokines, TNF-α, IL-10, MIG, IL-6, IP-10, M-CSF, G-CSF, GM-CSF, and IFN-α2, that can be used as good predictors of ICU requirement at 4-6 DfSO.

The sluggish sulfur reduction reaction, severe shuttle effect, and poor conductivity of sulfur species are three main problems in lithium-sulfur (Li-S) batteries. Functional materials with a strong affinity and catalytic effect toward polysulfides play a key role in addressing these issues. Herein, we report a defect-rich amorphous a-Fe3O4-x/GO material with a nanocube-interlocked structure as an adsorber as well as an electrocatalyst for the Li-S battery. The composition and defect structure of the material are determined by X-ray diffraction, high-resolution transmission electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy measurements. The distinctive open framework architecture of the as-engineered composite inherited from the metal-organic framework precursor ensures the stability and activity of the catalyst during extended cycles. The oxygen defects in the amorphous structure are capable of absorbing polysulfides and similarly work as catalytic centers to boost polysulfide conversion. Taking advantage of a-Fe3O4-x/GO on the separator surface, the Li-S battery shows a capacity over 610 mA h g-1 at 1 C and a low decay rate of 0.12% per cycle over 500 cycles and superior rate capability. The functional material made via the low-cost synthesis process provides a potential solution for advanced Li-S batteries.

Sb is a promising anode material for lithium-ion batteries, but it suffers from fast capacity fading. Previous works have shown that the combination of Sb with an active S or Se matrix improves the cycle stability of the electrodes, although there was no clear verification of the exact mechanism. In this study, we used ex situ X-ray diffraction, ex situ Raman spectroscopy, and in situ dilatometry to study the interactions of Sb with S and Se and to reveal the reasons for the superior cycle stability of Sb2Se3 electrodes. Our results show that the poor stability of Sb electrodes is due to the crystallization of Li3Sb, leading to the large volume change, high stress, and mechanical failure of the particles. Addition of S or Se into the matrix can inhibit the formation of crystalline Li3Sb, thus improving capacity retention. The stabilization effect is stronger for a Se matrix than for a S matrix because it enables the re-formation of Sb–Se bonds upon delithiation and prevents phase segregation. In addition,...

Despite advances in traditional lithium-ion batteries in the past decades, its high cost has always been a bottleneck for large-scale applications. In this work, we demonstrate it is possible to replace expensive cathodes such as LiCoO2 with inexpensive stainless steel to store energy via a stripping/deposition mechanism: during charging, the stainless-steel cathode removes charges by releasing metal ions into the electrolyte, and during discharge, the metal ions re-deposit on the electrode reversibly. An anion exchange membrane allows passage of anions to balance the charge and prevents cross-over of cations. We show here a battery with a stainless-steel cathode and a lithium metal anode with a high discharge voltage of 2.5 V and good reversibility. We also study the mechanism at the stainless-steel electrode, as well as the kinetics of the battery system. Our work can potentially reduce the cost of energy storage by turning common construction materials into cathode materials. In addition, a metal cathode undergoing stripping/deposition gives a theoretical energy density comparable to lithium-sulfur batteries and provides a new exciting direction for future energy storage development.

Background A heterologous recombinant adenovirus (rAd)-based vaccine, Gam-COVID-Vac (Sputnik V), showed a good safety profile and induced strong humoral and cellular immune responses in participants in phase 1/2 clinical trials. Here, we report preliminary results on the efficacy and safety of Gam-COVID-Vac from the interim analysis of this phase 3 trial. Methods We did a randomised, double-blind, placebo-controlled, phase 3 trial at 25 hospitals and polyclinics in Moscow, Russia. We included participants aged at least 18 years, with negative SARS-CoV-2 PCR and IgG and IgM tests, no infectious diseases in the 14 days before enrolment, and no other vaccinations in the 30 days before enrolment. Participants were randomly assigned (3:1) to receive vaccine or placebo, with stratification by age group. Investigators, participants, and all study staff were masked to group assignment. The vaccine was administered (0·5 mL/dose) intramuscularly in a prime-boost regimen: a 21-day interval between the first dose (rAd26) and the second dose (rAd5), both vectors carrying the gene for the full-length SARS-CoV-2 glycoprotein S. The primary outcome was the proportion of participants with PCR-confirmed COVID-19 from day 21 after receiving the first dose. All analyses excluded participants with protocol violations: the primary outcome was assessed in participants who had received two doses of vaccine or placebo, serious adverse events were assessed in all participants who had received at least one dose at the time of database lock, and rare adverse events were assessed in all participants who had received two doses and for whom all available data were verified in the case report form at the time of database lock. The trial is registered at ClinicalTrials.gov (NCT04530396). Findings Between Sept 7 and Nov 24, 2020, 21 977 adults were randomly assigned to the vaccine group (n=16 501) or the placebo group (n=5476). 19 866 received two doses of vaccine or placebo and were included in the primary outcome analysis. From 21 days after the first dose of vaccine (the day of dose 2), 16 (0·1%) of 14 964 participants in the vaccine group and 62 (1·3%) of 4902 in the placebo group were confirmed to have COVID-19; vaccine efficacy was 91·6% (95% CI 85·6–95·2). Most reported adverse events were grade 1 (7485 [94·0%] of 7966 total events). 45 (0·3%) of 16 427 participants in the vaccine group and 23 (0·4%) of 5435 participants in the placebo group had serious adverse events; none were considered associated with vaccination, with confirmation from the independent data monitoring committee. Four deaths were reported during the study (three [

Clostridium perfringens is considered one of the main causative agents of superacute enterocolitis, usually fatal in the equine species, due to the action of the β toxin, and is responsible for causing severe myonecrosis, by the action of the α toxin. The great importance of this agent in the equine economy is due to high mortality and lack of vaccines, which are the main form of prevention, which guarantee the immunization of this animal species. The aim of this study was to evaluate three different concentrations (100, 200 and 400μg) of C. perfringens α and β recombinant toxoids in equine immunization and to compare with a group vaccinated with a commercial toxoid. The commercial vaccine was not able to stimulate an immune response and the recombinant vaccine was able to induce satisfactory humoral immune response in vaccinated horses, proving to be an alternative prophylactic for C. perfringens infection. RESUMO: Clostridium perfringens é considerado um dos principais agentes causadores de enterocolites superagudas, geralmente fatais na espécie equina, devido à ação da toxina β, além de ser responsável por causar quadros graves de mionecrose, pela ação da toxina α. A grande importância desses agentes na equinocultura, deve-se a elevada mortalidade e a inexistência de vacinas, principal forma de prevenção, que garantam a imunização dessa espécie animal. O objetivo deste trabalho foi avaliar três diferentes concentrações (100, 200 e 400μg) dos toxóides recombinantes α e β de C. perfringens na imunização de equinos, bem como comparar com um grupo vacinado com um toxóide comercial. A vacina comercial não se mostrou capaz de estimular uma resposta imune e a vacina recombinante foi capaz de induzir resposta imune humoral satisfatória em equinos vacinados, provando ser uma alternativa profilática para infecção por C. Perfringens.

Traditional sodium-ion battery cathodes utilize the change in oxidation state of the transition metal(s) in the structure to accommodate the electron transfer during charge and discharge. Recent researches on sodium-rich compounds such as Na2RuO3 and Na2IrO3 suggest that anionic reaction with oxygen can be an additional source of electrons during electrochemical reactions. Here we demonstrate for the first time that stoichiometric NaVO3, despite the valence of vanadium of 5+, delivers a reversible capacity by activating it beyond 4.5 V. Elemental analysis confirms Na removal and insertion from/into NaVO3 during charge/discharge. X-ray photoelectron spectroscopy and X-ray absorption near-edge spectroscopy results show that the oxidation state of vanadium remains unchanged, while oxygen is likely to compensate for the charge transfer during charge/discharge. Theoretical calculation on spin density of electrons in the lattice also supports the involvement of oxygen during sodium removal. Our demonstration of the unique behaviors of NaVO3 provides a new exciting direction for research in sodium-ion battery cathodes.

Emerging sodium-selenium batteries suffer from volume expansion of the selenium cathode and shuttling effects of soluble intermediates. Confining selenium within the carbon matrix is the most adopted strategy to address these two issues, which is generally realized via a melt-infusion method. Herein, we developed a vapor-infiltration method to fabricate selenium/carbon composites that are advantageous over the melt-infusion route in terms of several aspects: it relieves the requirement of intensive mechanical mixing and simplifies the ratio optimization between selenium and carbon; it avoids selenium aggregation and makes it possible to utilize all of the surface and pores of the carbon host. Utilizing this method, we fabricated a selenium/graphene composite from thermally reduced graphene oxide with a selenium loading equal to 71 wt %, thus approaching the record value. The obtained composite achieved the highest reported to date initial Coulombic efficiency of 88% among various selenium cathodes, with superior rate and cycle performance (410 and 367 mA h g

P2-type Na0.7MnO2, with high capacity and excellent Na ion conductivity, is a promising cathode material for Na-ion batteries. However, its rapid capacity decay upon repeated cycles restricts its practical application. In this study, we demonstrate a facile method to surface coat and dope P2-Na0.7MnO2 with a P2-Na0.7Ni0.33Mn0.67O2 layer in a single step to enhance its cycle stability. The coating suppresses the dissolution of Mn ions into electrolyte, and the Ni dopant suppresses orthorhombic distortion, inhibits Na+/vacancy ordering and improves structural stability upon cycling. As a consequence, the coating enhances capacity retention from 62.2% (Na0.7MnO2) to 87.7% (Na0.7MnO2/20 wt% Na0.7Ni0.33Mn0.67O2) over 50 cycles, and from 20.7% (Na0.7MnO2) to 68.9% (Na0.7MnO2/20 wt% Na0.7Ni0.33Mn0.67O2) over 100 cycles without sacrificing the initial discharge capacity. In addition, the air-stable Na0.7Ni0.33Mn0.67O2 surface layer protects Na0.7MnO2 against air exposure.

Dual-ion battery with the use of both cations and anions as means of energy storage promises high power, as the ions do not have to travel from one electrode to another during charge and discharge. Though, actual rate performance of an electrode is highly dependent on material, electrode configuration and electrolyte. Here, we have identified the key parameters governing the rate performance of PF6− intercalation into graphite. Capacity is increased by increasing the surface area of the graphite material. Electrical conductivity and stability are enhanced with carbon addition in the electrode with reduced cut-off voltage. Operating voltage is reduced by increasing the salt concentration, and ionic conductivity is improved with the use of carboxymethyl cellulose as binder. Optimized graphite electrode delivers a capacity of about 90 mAh g−1 at 10 mA g−1, and 90% of it can still be accessible at a rate of 500 mA g−1, with excellent cycle stability for at least 200 cycles. The dual-ion battery is demonstrated to give power density superior to that of lithium-ion battery, and energy density superior to that of supercapacitor.

Capacity and operating voltage are critical parameters of cathode materials that dictate the energy density of lithium-ion batteries. Traditionally, redox reaction of the transition metal in the cathode limits the operating voltage and capacity during charge/discharge. Here, we simultaneously increase the capacity and operating voltage of LiVO3 by utilizing the anionic redox reaction of oxygen in the lattice. While LiVO3 gives a capacity of 235 mAh g−1 with an average potential of 2.18 V vs. Li/Li+ between 1.5 and 3.0 V from the vanadium redox reaction, they increase to 358 mAh g−1 and 2.55 V vs. Li/Li+, respectively, between 1.5 and 4.8 V. The higher capacity and operating voltage are due to the extraction of 0.56 mol of Li from its lattice when charging it to 4.8 V, despite vanadium originally in its highest oxidation state of 5+. The additional charge transfer derives from oxygen in the material, as X-ray spectroscopies and density functional theory calculation demonstrate the presence of peroxide species in the material and spin density around oxygen atoms, respectively, upon lithium extraction. Structural and gas analyses further reveal the stability of the anionic reaction, with only 0.21% volume change during lithium extraction with no O2 gas release.

Metal chalcogenides undergoing alloying and conversion mechanism can give high capacity as anode for lithium-ion batteries. However, large volume change and phase segregation lead to poor cycle performance. In this study, we focus on Sb2Se3 and develop methods to enhance its long-term stability and reversibility. In particular, we find that carbon encapsulation reduces volume change during lithiation/delithiation and facilitates the recombination process of Sb and Se even after long cycling. With an addition of 20 wt% acetylene black, the Sb2Se3/C nanocomposite material exhibits an excellent cycle performance with a charge capacity of 545 mAh g−1 at 250 mA g−1 after 1000 cycles, corresponding to a capacity retention of 99.3%. We also demonstrate a full cell with LiFePO4 cathode and Sb2Se3/C anode that is capable of delivering a stable capacity of 340 mAh g−1 at 1 A g−1 (about 3 C rate) after 300 cycles.

3 V rechargeable Cu–Al batteries are highly desirable for large-scale energy storage owing to the low cost and excellent scalability of the two metal electrodes. However, they still undergo irreversible processes such as the crossover of Cu ions, dendrite growth during alloy reaction at Al anode, and side reaction between AlLi and the electrolyte. In this work, we solve the poor reversibility of the battery by modifying the cathode, anode and electrolyte. Specifically, a polyacrylonitrile coating on the copper cathode anchors the dissolved Cu ions, polyvinylpyrrolidone additive in the electrolyte enables dendrite-free AlLi alloy formation and a graphene oxide layer on the Al anode suppresses reductive decomposition of the electrolyte, thereby improving average Coulombic efficiency. Our work overcomes some of the critical challenges in Cu–Al batteries and opens new opportunities for the development of low-cost, high-performance rechargeable metal-metal batteries.

A peroxogermanate thin film was deposited in high yield at room temperature on graphene oxide (GO) from peroxogermanate sols. The deposition of the peroxo-precursor onto GO and the transformations to amorphous GeO2, crystalline tetragonal GeO2, and then to cubic elemental germanium were followed by electron microscopy, XRD, and XPS. All of these transformations are influenced by the GO support. The initial deposition is explained in view of the sol composition and the presence of GO, and the different thermal transformations are explained by reactions with the graphene support acting as a reducing agent. As a test case, the evaluation of the different materials as lithium ion battery anodes was carried out revealing that the best performance is obtained by amorphous germanium oxide@GO with >1000 mAh g–1 at 250 mA g–1 (between 0 and 2.5 V vs Li/Li+ cathode), despite the fact that the material contained only 51 wt % germanium. This is the first demonstration of the peroxide route to produce peroxogermanate ...

Botulism is a paralytic disease caused by the intoxication of neurotoxins produced by Clostridium botulinum. Among the seven immunologically distinct serotypes of neurotoxins (BoNTs A − G), serotypes C and D, or a chimeric fusion termed C/D or D/C, are responsible for animal botulism. The most effective way to prevent botulism in cattle is through vaccination; however, the commercially available vaccines produced by detoxification of native neurotoxins are time-consuming and hazardous. To overcome these drawbacks, a non-toxic recombinant vaccine was developed as an alternative. In this study, the recombinant protein vaccine was produced using an Escherichia coli cell-based system. The formaldehyde-inactivated E. coli is able to induce 7.45 ± 1.77 and 6.6 ± 1.28 IU/mL neutralizing mean titers against BoNTs C and D in cattle, respectively, determined by mouse neutralization bioassay, and was deemed protective by the Brazilian legislation. Moreover, when the levels of anti-BoNT/C and D were compared with those achieved by the recombinant purified vaccines, no significant statistical difference was observed. Cattle vaccinated with the commercial vaccine developed 1.33 and 3.33 IU/mL neutralizing mean titers against BoNT serotypes C and D, respectively. To the best of our knowledge, this study is the first report on recombinant E. coli bacterin vaccine against botulism. The vaccine was safe and effective in generating protective antibodies and, thus, represents an industry-friendly alternative for the prevention of cattle botulism.

Ebola fever is an acute highly contagious viral disease characterized by severe course, high mortality and development of hemorrhagic syndrome (tendency to skin hemorrhage and bleeding of mucous membranes). The mortality rate of the disease 60–90%. Nowadays, there are no licensed specific therapeutic agents for Ebola in the world. Monoclonal antibodies (MAbs) having viral neutralizing activity with high specificity to the GP protein of the Ebola virus are considered as candidate highly effective antiviral drugs. In our study, for the first time a panel of mouse monoclonal antibodies specifically binding to EBOV GP protein was obtained using recombinant human adenovirus 5 serotype, expressing GP protein (Ad5-GP). The virus-neutralizing capacities of antibodies were evaluated on the Ebola virus cell infection model, as well as recombinant vesicular stomatitis virus pseudotyped by GP Ebola virus protein (rVSV-GP) cell infection model. Based on the results of virus neutralization, two most promising clones were selected, the specific and protective capacities of which were determined. The study of the protection of selected individual antibody clones, as well as their combinations on the model of lethal infection of rhesus macaques with Ebola virus showed that intravenous administration of a mixture of antibodies in the amount of 50 mg/kg 24 h after infection leads to the survival of 100% of the animals, while individual clones of antibodies possess partial protection (0–30%). The results of the study suggest the important role of antibodies in controlling replication of the Ebola virus in vivo and show the possibility of using a mixture of antibodies specific to the GP to protect against lethal infection with the Ebola virus in the post-infected mode of administration.

Aqueous rechargeable Zn-ion batteries (ARZIBs) are attractive due to their low cost, high safety and environmental friendliness. However, the development of ARZIBs still faces many challenges. One of the biggest challenges is to find suitable cathode materials for reversible Zn2+ ions insertion/extraction. In this work, we synthesize a Prussian blue analogue (PBA) with a new chemical composition, vanadium hexacyanoferrate (VHCF), via a simple co-precipitation method and study its performance as a cathode material for an aqueous rechargeable Zn-ion battery. The VHCF with two electrochemical redox active sites, V and Fe, delivers a three-electron redox reaction with a capacity of 187 mA h g−1 at current density of 0.5 A g−1. Even at a current rate of 5 A g−1, VHCF can still deliver a large capacity of 122 mA h g−1. The Zn//VHCF battery also exhibits a long cycle life of 1000 cycles with excellent capacity retention of 87.8% and a high Coulombic efficiency close to 100%. During the first charging process, the cubic structure of VHCF changes to a rhombohedral phase, a structure where the Zn2+ ions can be reversibly inserted into and extracted from in subsequent cycles. The promising performances make VHCF an attractive candidate as cathode material for ARZIBs system.

Water-enabled crystallization of amorphous anodic SnO2 is reported. After low-temperature water soaking for a short period of time (e.g., 60 °C for 2 h), mesoporous rutile SnO2 with a remarkably increased surface area is achieved (nearly 2-fold that of the as-anodized SnO2 and 3.3 times that of SnO2 annealed at high temperature). Closer examination reveals that the water-crystallized SnO2 possesses a hierarchical nanostructure that features 1D nanochannels (e.g., ∼30 nm in diameter) and thin channel walls (e.g., 20 nm thick) that are comprised of tiny nanoparticles (e.g., ∼4 nm big). The water-crystallized SnO2 directly grown on the copper foil can be directly applied as a novel type of binder-free electrode for sodium-ion storage, delivering a high reversible capacity of 514 mA h g−1 after 100 cycles at a current rate of 0.1C.

Cu–Ni–Mn-based ternary P2-type NaxCu0.15Ni0.20Mn0.65O2 (x = 0.50, 0.67, and 0.75) cathodes for sodium-ion batteries (SIBs) are synthesized by a co-precipitation method. We find that Na content plays a key role on the structure, morphology, and the charge–discharge performances of these materials. For x = 0.67 and 0.75, superstructure from Na+-vacancy ordering is observed, while it is absent in the x = 0.50 sample. Despite the same synthesis conditions, materials with x = 0.67 and 0.75 show smaller particle sizes compared to that of the x = 0.50 sample. In addition, redox potentials of the materials differ significantly even though they have the same transition metal ratios. These differences are attributed to the changes in local structures of the as-prepared materials arising from the different amount of Na and possibly oxygen in the lattice. Materials with x = 0.67 and 0.75 show excellent rate performance and cycle stability when tested as cathode material of SIBs. Average discharge potential is as high...

Graphene, including pristine graphene and its analogues of graphene oxide and reduced graphene oxide, is revolutionizing the way we design high performance devices, particularly in the areas of sustainable energy and environmental technologies. From environmental remediation and sensing to energy conversions and storage, there are many successful cases of graphene applications. Instead of being a standalone working material, graphene is almost always coupled with another active material as a composite. With its high surface-to-bulk ratio, efficient heat transfer, and electron conduction, the interfacing with graphene not only helps to overcome such limitations in the bare working material but actually accentuates them. To achieve this, the strategy of surface functionalization of graphene, with either soft matters (e.g., organics, molecular linkers, proteins) or solid inorganic matters (e.g., metal nanoparticles, oxide semiconductors), holds the key to enabling the fabrication of high performance composit...

In South Africa, the problem of service delivery cuts across all municipalities as manifested by citizen protests across the country on almost daily basis. To mitigate the costs associated with the protests, the South African government has placed emphasis on the role played by human resources management through instituting legislative frameworks, such as the the White Paper on Human Resource Management in the Public Service (1997). Despite this effort, the human resource management practices of municipalities continue to be criticized, by both municipal internal staff and citizenry. Service delivery in the South African context is regarded as one of the cornerstone indicators of how the government affords its citizens access to quality life as enshrined in its constitution. This paper is one of the studies based on the South African context attempting to explain the problem of service delivery by looking at perceived fairness in human resource management (HRM) practices by employees of municipalities and how such perceptions affect their motivation to work. Using the tenets of the organizational justice theory, the authors hypothesize that perceived HRM practices of municipalities can be predictors of employee motivation. Quantitative data collected from employees of nine randomly selected municipalities in the Free State Province are used to create indices for the different HRM practices as well as employee motivation. Significant correlation tests are performed. Results show a positive correlation between perceived fairness in the HRM practices of municipalities and employees’ motivation at .05 and .01 levels of significance. This means that fair HRM practices of municipalities promote employee motivation

Nowadays gene and cell therapy become the basic methods in regenerative medicine. However only few gene and cell products are currently approved for clinical usage. Biosafety problems, complexity of cell and gene technologies and high cost of manufacturing are the main reasons for the slow introduction of such approaches in practical medicine. Treatment of hereditary diseases of the immune system based on the correction of the mutant gene by delivering functional recombinant gene into WBC is the first successfully employed in the clinical practice approach of cell-mediated or ex vivo gene therapy. Earlier we have reported the strategy of the cell-mediated gene therapy based on umbilical cord blood mononuclear cells transduced with adenoviral vectors carrying recombinant genes encoding neurotrophic factors for treatment neurodegenerative diseases, neurotrauma and stroke. Significant disadvantage of this method is the usage of the umbilical cord blood mononuclear cells as a cell carrier for the therapeutic genes. Considering immunodeficiency treatment and our own data we developed a new approach of recombinant gene delivery for personalized ex vivo gene therapy. The method is based on autoinfusion of patient's WBC transduced with recombinant therapeutic genes for correction of certain pathological conditions. In the present study for the first time the human gene-modified leucoconcentrate (GML) producing recombinant reporter gene encoding green fluorescent protein (GFP) was obtained without culturing WBC in vitro. The routine unit of peripheral blood (450 ml) was collected into the plastic blood bag and the leucocyte- and platelet-rich concentrates (50 ml) were obtained by standard method using Macopress Smart (Macopharma, France). Afterwards the equal volume of hydroxyethyl starch 6% was added into the plastic blood bag which was centrifuged (DP-2065 R PLUS, Centrifugal Presvac RV; Presvac, Buenos Aires, Argentina) at 350 rpm for 10 min at 10°C. The obtained supernatant was transferred into the new plastic blood bag using manual plasma extractor FK-01 (Leadcore, Russia) and 200 ml of saline was added into the bag which was centrifuged at 1300 rpm for 10 min at 10°C and the supernatant was expressed out of the bag so that the remaining solution in the bag (30 ml) contained leucoconcentrate (WBC - 45.56 ± 23.93 × 106/ml and RBC - 1.76 ± 3.33 × 109/ml). Transduction of WBC with chimeric adenoviral vector (Ad5/35) carrying GFP gene was performed in the plastic bag with MOI 5 according to the count of WBC in the leucoconcentrate. After transduction for 12 hours, 200 ml of saline was added to the bag with leucoconcentrate, the mixture was centrifuged at 1000 rpm for 10 min at 10°C and the supernatant was squeezed out of the bag. The remained in the bag solution (30 ml) was considered as gene-modified leucoconcentrate carrying GFP gen (WBC - 22.63 ± 8.90 × 106/ml and RBC - 1.77 ± 1.21 × 109/ml). For in vitro study of GFP gene expression the samples of GML-GFP were cultivated for 60 hours after GML-GFP preparation. Fluorescent microscopy in the cytoplasm of the transduced WBC showed specific intensive green fluorescence. Flow cytometry analysis demonstrated that 2.5% of WBC from the GML-GFP efficiently expressed GFP. Thus leucoconcentrate after 72 h of transduction with Ad5/35-GFP with MOI 5 resulted in 2.5% of the GFP-positive cells. Thus the results of this study represent a simple, safe and effective approach for preparation of GML for personalized ex vivo gene therapy aimed at temporary production of the specific recombinant biologically active molecules for pathogenetic therapy of the varied nosological form, such as trauma, ischemic, degenerative, autoimmune, infection and other diseases. This study was supported by the grant of Russian Science Foundation 19-75-10030. Disclosures No relevant conflicts of interest to declare.

Dual-ion battery (DIB) can potentially provide higher power, lower cost and faster charging capability than traditional lithium-ion batteries. Even though graphite can effectively accommodate anions as a cathode for DIB, the high working voltage of around 5 V vs. Li/Li+ leads to continuous side reactions, yielding to low Coulombic efficiency (CE

The carbon-based materials are promising hosts for metallic Li owing to their merits of excellent chemical stability, high porosity and electrical conductivity, as well as lightweight. Nevertheless, homogeneously pre-depositing Li into the carbon hosts remains a challenge owing to the inherited lithiophobic surface of carbon materials. In this contribution, we found that the Cu2+1O was lithiophilic and the origin of the lithiophilicity of Cu2+1O was investigated. Furthermore, a facile approach was presented to uniformly coat a thin Cu2+1O layer onto commercial carbon papers (CPs) to modify the surfaces of CPs into lithiophilic and after molten Li infusion, the Li-Cu2+1O-CP composite anode was fabricated. The CP could accommodate the huge volume change of Li and suppress the Li dendrite growth during cycling. As a result, the Li-Cu2+1O-CP composite anode delivered a stable repeating Li plating and stripping behavior (500 cycles at 10 mA cm−2 with 3 mAh cm−2Li) based on symmetric cell, as well as enhanced rate capability and cycling stability (97% capacity retention after 500 cycles) in full cells integrated with a commercial LiFePO4 cathode.

The results of experimental and theoretical studies on the justification of a new approach to measuring the temperature of melts using an optical fiber pyrometer are given in the paper. The paper presents an analytical review of alternative methods and means of measuring the melt temperature. Proposed from the melt using a special crucible to form a radiant cavity type model a blackbody. A functional diagram of the device measuring the temperature of the melt by the proposed method. Calculation and experimental results on the substantiation of spectral characteristics of crucible materials are presented. The experimental dependence of the absorption of quartz glass brand QI at room temperature and family dependency in the range from 500°C to 1100°C when the temperature of the radiating cavity of a blackbody from 500°C to 1100°C. On the basis of classical representations of the calculations of the coefficient of blackness of the crucible radiative model type, a blackbody given its design.

Botulism is a potentially fatal intoxication caused by botulinum neurotoxins (BoNTs) produced mainly by Clostridium botulinum. Vaccination against BoNT serotypes C and D is the main procedure to control cattle botulism. Current vaccines contain formaldehyde-inactivated native BoNTs, which have a time-consuming production process and pose safety risks. The development of non-toxic recombinant vaccines has helped to overcome these limitations. This study aims to evaluate the humoral immune response generated by cattle immunized with non-purified recombinant fragments of BoNTs C and D. Cattle were vaccinated in a two-dose scheme with 100, 200 and 400 &micro, g of each antigen, with serum sampling on days 0, 56, 120, and 180 after vaccination. Animals who received either 200 or 400 &mu, g of both antigens induced titers higher than the minimum required by the Brazilian ministry of Agriculture, Livestock and Food Supply and achieved 100% (8/8) seroconversion rate. Animals vaccinated with commercial toxoid vaccine had only a 75% (6/8) seroconversion rate for both toxins. Animals that received doses containing 400 &micro, g of recombinant protein were the only ones to maintain titers above the required level up until day 120 post-vaccination, and to achieve 100% (8/8) seroconversion for both toxins. In conclusion, 400 &micro, g the recombinant Escherichia coli cell lysates supernatant was demonstrated to be an affordable means of producing an effective and safe botulism vaccine for cattle.

The work described in this paper was supported by a General Research Fund (CityU 21202014) and the SFC/RGC Joint Research Scheme (X-CityU102/14) from the Research Grants Council of the Hong Kong Special Administrative Region, China and 2014_HK-Scot-0072 from the Scottish Funding Council. Antimony-based electrodes are promising as fast charging anodes for lithium-ion batteries because their operating potential is about 0.8 V vs. Li/Li+, far away from the plating potential of Li. However, their capacity decays fast due to large volume expansion, the issue which has often been addressed through the use of nano-sized materials. Herein, we utilize an ion-dipole interaction between polyimide and carboxymethyl cellulose which suppresses particle cracking and holds the particle together to enable antimony anodes utilizing micron-sized Sb particles for high rate applications. Sb anode with 9.4% polyimide coating exhibits a high reversible capacity of 580 mAh g−1 at 1 A g−1 with excellent cycle performance. The rate performance of the electrode can be further improved by adding 5% acetylene black during the polyimide coating process. Even at a current rate of 20 C (13.2 A g−1), a highly reversible capacity of 380 mAh g−1 can be obtained. The superior high-rate capability and excellent stability of Sb anodes are further verified by full-cell tests with LiFePO4 cathodes. Postprint

In the experiment, the reaction of the rat oral mucosa to fractional mechanical and laser treatment performed by radiation of a diode laser with a wavelength of 980 nm in various combinations of the average power of laser radiation, the pulse duration and energy of the laser radiation, along with the fill factor was investigated. Optical and histological examination of the rat oral mucosa during its regeneration after fractional treatment was performed. It was found that on the 5 th day after a single-shot fractional laser treatment, the number of mitotically dividing cells exceeds the number of those cells after a single-shot fractional mechanical treatment and in the control area. It has been found that on the 28 th day after a three-fold fractional treatment, the surface of the mucosa is visually bleached, and after the laser treatment, the connective tissue of the mucosa lamina propria and the submucosal layer contains fibrous structures and cellular elements, mainly myo- and fibroblasts. It has been found that during the regeneration on the 28 th day after a three-fold fractional laser treatment, the thickness of the epithelium and the thickness of the submucosal layer with lamina propria of mucosa increase in comparison with the control.

Optical and histological methods were used to examination of influence the power and pulse duration of 980-nm diode laser to the dimensions and morphology of tissue around fractional micro injuries created by the radiation of that laser in the oral mucosa of rats in vivo. The power of laser radiation (P) varied in the range of 1÷21 W, and its pulse duration (tp) - in the range 50÷500 ms. Histological examination showed that in the mucosa of the oral cavity after the laser fractional irradiation, there following effects are found: a tissue defect, a transudate in the lumen of ablative micro injury, stretching and compacting effect of the nuclei of the basal epithelium, the disappearance of granules of the keratohialin, destroying the structure of the connective tissue, erythrocyte stasis in the vessels, the disappearance of transverse striation in the muscle fibers in muscle layer. It has been found that ablative micro injury begins to form up at P = 5 W, tp = 100 ms and affects only the epithelial layer of the mucosa. At P = 7 W, tp = 120 ms, the ratio of width to depth of ablative micro injury is 1 : 1, and at P = 10 W, tp = 100 ms, an ablative micro column with ratio of 1 : 1.5 is formed in the epithelial and submucosal layers of the mucosa. The laser effect with P = 15 W, tp = 200 ms leads to lengthening of the ablation micro-column to 1 : 2, with the bottom of the ablative micro column reaching the muscular layer. With a further growth of laser power or pulse duration, the width of the micro injury increases, and the growth of the micro injury depth is slowed down so that the micro column buildup is ceased.

Spinel Li 4 Mn 5 O 12 , a well-known 3 V Li-ion battery (LIB) material with excellent cycling stability and good rate capability, is examined as Na-ion battery (NIB) cathode for the first time. Electrochemical studies clearly show that Na ions can be reversibly inserted into and extracted from the three-dimensional spinel structure. However, unlike in LIB, the available capacity in NIB is strongly dependent on the particle size and current rate due to the sluggish Na-ion transport in solid phase. Cycle performance of Li 4 Mn 5 O 12 in NIB is also inferior to that in LIB. Ex-situ X-ray diffraction study indicates a gradual loss of crystallinity with cycling, and that the crystal lattice undergoes an irreversible expansion during the initial 20 cycles. Inductively coupled plasma spectroscopy shows a decrease of Li/Mn ratio in Li 4 Mn 5 O 12 with cycling. The results suggest that Li ions are removed from the material during the charging process. The charge-discharge mechanism is also discussed in the paper.

A composite of pyrite FeS2 microspheres wrapped by reduced graphene oxide (FeS2/rGO) has been synthesized by a facile one-step solvothermal method and applied as an anode in lithium ion batteries (LIBs). Impedance measurements and transmission electron microscopy show that incorporation of rGO significantly decreases the charge transfer resistance and improves the structural stability of the composite. As an anode material for LIBs, the composite exhibits a high capacity of 970 mA h g−1 at a current density of 890 mA g−1 after 300 cycles. Additionally, this composite anode shows impressive performance especially at high current densities. The LIB shows a capacity of 380 mA h g−1 even at a high current density of 8900 mA g−1 (10C) over 2000 cycles, demonstrating its potential for applications in LIBs with long cycling life and high power density.

While sodium-ion batteries (SIBs) are considered as a next-generation energy storage device because of the higher abundance and lower cost of sodium compared to those of lithium, developing high-power and stable cathode materials remains a great challenge. Here, micron-sized plate-like copper-substituted layered P2-type Na0.67CuxMn1−xO2 is demonstrated to rapidly charge and discharge within 5 minutes while giving a capacity of more than 90 mA h g−1, corresponding to a half-cell energy density of 260 W h (kg cathode)−1 at a power density of 3000 W (kg cathode)−1, which is comparable to that of high-power lithium-ion cathodes. The materials show excellent stability, retaining more than 70% of the initial capacity after 500 cycles at 1000 mA g−1. The good cycle and rate performances of the materials are attributed to copper in the lattice, which stabilizes the crystal structure, increases the average discharge potential and improves sodium transport. This makes Na0.67CuxMn1−xO2 an ideal choice as a cathode for high-power sodium-ion batteries.

Thermal stability of a lithium-rich layered oxide cathode material with composition 0.5Li4/3Mn2/3O2–0.5LiNi1/3Co1/3Mn1/3O2 (LMO–NCM) is investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Investigated material shows higher thermal stability (higher onset temperature) than LiCoO2. The state of charge and previous cycling history of LMO–NCM, particularly activation of lithium manganese oxide (LMO) “component” during first charge, affect its thermal stability. Activation of LMO has an ambivalent effect on cathode thermal stability: on the one hand, the onset temperature of cathode decomposition is increased, probably due to the change in oxidation states of Ni, Co and Mn after the first cycle. On the other hand, the enthalpy of decomposition increases, presumably due to formation of unstable oxygen in the lattice. X-ray diffraction (XRD) analyses of cathodes before and after thermal decomposition at 600 °C indicate differences in decomposition reactions of charged cathodes, depending on state of charge and cycling history.

Thermal stability of charged LiCoO 2 cathodes with various surface areas of active material is investigated in order to quantify the effect of LiCoO 2 surface area on thermal stability of cathode. Thermogravimetric analyses and calorimetry have been conducted on charged cathodes with different active material surface areas. Besides reduced thermal stability, high surface area also changes the active material decomposition reaction and induces side reactions with additives. Thermal analyses of LiCoO 2 delithiated chemically without any additives or with a single additive have been conducted to elaborate the effect of particle size on side reactions. Stability of cathode–electrolyte system has been investigated by accelerating rate calorimetry (ARC). Arrhenius activation energy of cathode decomposition has been calculated as function of conversion at different surface area of active material.

The effect of lithium boron oxide (LBO) coating on the electrochemical performance of orthorhombic LiMnO2 (o-LiMnO2) cathode for lithium-ion batteries is investigated. o-LiMnO2 synthesized via solid state synthesis technique is modified with LBO addition. The presence of LBO is identified via Fourier transform infrared spectroscopy analysis. o-LiMnO2 is observed to transform to a spinel-like phase during cycling which undergoes capacity fading. Studies indicate that the presence of 1–2 wt% LBO results in an improved capacity and better capacity retention with cycling. The pristine sample reveals a maximum specific capacity of 172 mAhg−1, whereas the LBO-modified samples display about 189.1 mAhg−1 in the cycling tests conducted at a rate of 50 mAg−1 in the voltage range of 2–4.5 V. After 70 cycles, the LBO-modified LiMnO2 displayed higher capacity retention of 175 mAhg−1 as compared to the pristine sample that exhibited 130 mAhg−1. By analyzing the charge–discharge behavior, it is observed that the capacity obtained from lithium insertion into the tetrahedral sites of the spinel structure is more or less constant throughout the cycling and that the bulk of the capacity loss is resulting when lithium is inserted into the octahedral sites of the spinel structure. Impedance measurement reveals a reduced charge-transfer resistance for the LBO-modified samples suggesting that the presence of LBO is countering capacity loss arising from insertion of lithium into the octahedral sites thus contributing to the overall cycling stability.

In laboratory experiments, Li-O2 systems show "sudden death" at capacities far below the theoretical value. Identifying how discharge products limit the total capacity is crucial in Li-O2 system. We investigated the effect of Li2O2 seed layer deposited on carbon cathode under potentiostatic conditions at increasing overpotentials to the subsequent slow discharge at galvanostatic condition. The discharge capacity attainable in the second step is found to vary by more than a factor of 3 depending on the history, i.e., the seed layer. These results provide evidence that the battery history is decisive for the total discharge capacities.

Co3O4 nanoparticles are grown on nitrogen modified microwave exfoliated graphite oxide (NMEG) with weight ratio controlled from 10% to 70%. Electrochemical performance reveals that the obtained Co3O4/NMEG composite as Li-ion battery anode exhibits improved cycle stability, excellent reversible capacity, high current rate performance, and reduced irreversible capacity loss in the initial cycle compared to pure Co3O4 without graphene or Co3O4 on thermally reduced graphene oxide (tRG-O). The 70%Co3O4/NMEG composite has initial irreversible capacity of 230 mAh g−1 (first cycle efficiency of 77%), and 910 mAh g−1 of capacity is retained after 100 cycles. The 70%Co3O4/tRG-O delivers a reversible capacity of 750±20 mAh g−1, and the irreversible capacity loss during the first cycle is 700±20 mAh g−1. Nitrogen functional groups in NMEG, especially pyridinic and pyrrolic N are advantageous for the Co3O4 growth. Furthermore, the N modification is effective in reducing the oxygen content of chemically prepared graphene and hence is good for Co3O4 dispersion and the amelioration of first cycle efficiency, demonstrating the potential of NMEG based composite as high performance Li-ion battery anode materials.

We describe a method for conformal coating of reduced graphene oxide (rGO) by stibnite nanocrystallites. First, graphene oxide (GO) supported amorphous hydroperoxoantimonate was produced using the recently introduced hydrogen peroxide synthesis route. Sulfurization of the amorphous antimonate yielded supported antimony(V) oxide nanoparticles and sulfur, which were then converted by high temperature vacuum treatment to 15–20 nm rGO supported stibnite. The usefulness of the new material and synthesis approach are demonstrated by highly efficient and stable lithium battery anodes. Since both sulfur lithiation and antimony–lithium alloying are reversible, they both contribute to the charge capacity, which exceeded 720 mA h g–1 after 50 cycles at a current density of 250 mA g–1. The very small crystallite size of the stibnite provides a minimum diffusion pathway and allows for excellent capacity retention at a high rate (>480 mA h g–1 at 2000 mA g–1 was observed). The nanoscale dimensions of the crystallites minimize lithiation-induced deformations and the associated capacity fading upon repeated charge–discharge cycles. The flexibility and conductivity of the rGO ensure minimal ohmic drop and prevent crack formation upon repeated cycles.

Silicon is a promising anode material for lithium-ion batteries because of its high gravimetric/volumetric capacities and low lithiation/delithiation voltages. However, it suffers from poor cycling stability due to drastic volume expansion (>300%) when it alloys with lithium, leading to structural disintegration upon lithium removal. Here, it is demonstrated that titanium atoms inside the silicon matrix can act as an atomic binding agent to hold the silicon atoms together during lithiation and mend the structure after delithiation. Direct evidence from in situ dilatometry of cosputtered silicon-titanium thin films reveals significantly smaller electrode thickness change during lithiation, compared to a pure silicon thin film. In addition, the thickness change is fully reversible with lithium extraction, and ex situ post-mortem microscopy shows that film cracking is suppressed. Furthermore, Raman spectroscopy measurements indicate that the Si-Ti interaction remains intact after cycling. Optimized Si-Ti thin films can deliver a stable capacity of 1000 mAh g-1 at a current of 2000 mA g-1 for more than 300 cycles, demonstrating the effectiveness of titanium in stabilizing the material structure. A full cell with a Si-Ti anode and LiFePO4 cathode is demonstrated, which further validates the readiness of the technology.

Recombinant avian adenovirus CELO bearing sequence RGD in the structure of a long-fiber HI loop was designed. Experiments in vitro revealed that the introduction of an RGD motif into the fiber of CELO increased the ability of the virus to be attached to a surface of CAR-negative cells, and raised the efficiency of the process of internalization of the virus both in CAR-positive and in CAR-negative cells.