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Abstract High Li‐storage‐capacity particles such as alloying‐based anodes (Si, Sn, Ge, etc.) are core components for next‐generation Li‐ion batteries (LIBs) but are crippled by their intrinsic volume expansion issues. While pore pre‐plantation represents a mainstream solution, seldom do this strategy fully satisfy the requirements in practical LIBs. One prominent issue is that porous particles reduce electrode density and negate volumetric performance (Wh L−1) despite aggressive electrode densification strategies. Moreover, the additional liquid electrolyte dosage resulting from porosity increase is rarely noticed, which has a significant negative impact on cell gravimetric energy density (Wh kg−1). Here, the concept of judicious porosity control is introduced to recalibrate existing particle design principles in order to concurrently boost gravimetric and volumetric performance, while also maintaining the battery's cycle life. The critical is emphasized but often neglected role that intraparticle pores play in dictating battery performance, and also highlight the superiority of closed pores over the open pores that are more commonly referred to in the literature. While the analysis and case studies focus on silicon‐carbon composites, the overall conclusions apply to the broad class of alloying anode chemistries.

AbstractChitosan, a biopolymer known for its biocompatibility, biodegradability, and chemical adaptability, has attracted significant attention in scientific research. Chitosan-metal nanocomposites represent an emerging area of exploration. Among these, Chitosan-Fe nanocomposite has gained prominence due to its various applications, including photoremediation, bioimaging, and drug delivery systems. In this study, we delved into the synthesis and physicochemical properties of Chitosan-Fe nanocomposites. These nanocomposites exhibited a spherical structure with active binding sites that allowed for the functionalization of Fe3+ ions on their surface. Density functional theory simulations corroborated this alteration, demonstrating changes in surface charge properties resulting in increased mechanical strength. A key finding of this study is the enhanced antibacterial activity exhibited by the Cs-Fe nanocomposites against both Escherichia coli (62.5 µg/mL) and Staphylococcus aureus (125.25 µg/mL), surpassing that of bare Chitosan nanoparticles. Furthermore, our investigation confirms the therapeutic safety of the Chitosan-Fe nanocomposite. The cell viability calculated by MTT assay and accepted therapeutic dose concentration for CS-Fe NC was 125 ug/mL whereas for CSNP < 15.62 µg/mL. This underscores the nanocomposite’s potential in biomedical applications. In addition to its biomedical promise, the Chitosan-Fe nanocomposite also demonstrates remarkable potential in environmental remediation, particularly in the removal of hexavalent chromium.

Introduction: Unexpected return to operation theater carries high rate of morbidity and mortality for patients, in addition to increased hospital stay. A close look at such cases would help in identifying high-risk patients thus improving outcome. The aim of the study was to evaluate the incidence of Obs/Gyn cases returning to OT due to postoperative complications in a tertiary care hospital. Methods: It was a retrospective observational study done at tertiary care hospital settings affiliated with academic center in the UAE. The records of patients were scrutinized, and all booked and non-booked pregnant patients of any age undergoing emergency or elective obstetrics or gynecological procedure from January 1, 2016 to December 31, 2020 were enrolled in the study. Relaparotomy was defined as cases opened within same admission and causally associated with previous primary obstetrics or gynecological operation. Result: A total of 21,276 operations were performed from 2016 to 2020. In these 4 years, 33 patients had unexpected return to operation theater making the incidence of re-exploration to 0.15% (33/21,276). There were 16 (48.48%) emergency operations and 17 (51.52%) elective operations previously done on these patients. The most common primary procedure for which re-exploration was done was lower segment caesarean section done in 11 (33.3%) of cases followed by laparoscopic adhesiolysis and myomectomy. Hematoma in the pelvic region and ooze from raw area were the most common per-operative finding in 48.48% of cases. There was no mortality in the abovementioned cases; however, 2 (6.06%) had early acute kidney injury and both recovered from it. Discussion: The incidence of relaparotomy in our hospital is comparable to international literature. Most patients returned to OT within 48 h. Bleeding was the most common indication for laparotomy, and lower segment cesarean section was most common primary operation. This study underscores the need for meticulous hemostasis before closing to avoid return to OT. Conclusion: Return to OT for the right indication saves life. Mortality in such cases may be reduced by earlier detection and treatment of postoperative problems, consideration of relaparotomy, active ICU monitoring, and postoperative care.

Abstract Using a syringe pump setup, the authors conducted water flow experiments through porous reduced graphene oxide (rGO). A variety of anions and cations were added to the water to study its effect on energy harvesting. More specifically, the authors performed tests to study effect of: (1) ion concentration in water, (2) type of anion used, (3) type of cation used, and (4) effect of flow rate. The test data indicates that water flow through rGO networks can directly induce drift of charge carriers in graphene and thus generate electricity. Graphene is ideally suited for this application, since it possesses high mobility charge carriers that are ready to be coupled to moving ions present in the flowing fluid. The proposed rGO material could enable harvesting of the ubiquitous, abundant, and renewable mechanical energy of moving water directly to electrical energy. Unlike traditional schemes, the graphene material directly converts the flow energy into electrical energy without the need for moving parts. Such graphene coatings could potentially replace conventional batteries (which are environmentally hazardous) in low‐power, low‐voltage, and long service‐life applications. Once scaled up, this concept offers a potentially transformative approach to energy harvesting, as opposed to incremental advances in current technologies.

Background and Aim: The Indian and global poultry industries suffer significant economic losses due to Mycoplasma gallisepticum (MG) and Mycoplasma synoviae (MS) infections, which adversely affect egg production, hatchability, weight gain, and feed efficiency in farms, thus decreasing the overall production efficiency. This study aimed to determine the percent positivity and phylogenetic analysis of MG, MS, and co-infection of both mycoplasmas in commercial poultry farms across different states of India from 2017 to 2021. Materials and Methods: A total of 3620 tracheal or choacal swabs were collected from breeder and layer farms showing clinical signs of avian mycoplasma infections from commercial poultry farms across India, and the percent positivites for MG, MS, and co-infection of both mycoplasmas were determined by Polymerase chain reaction using the 16S rRNA and vlhA genes amplification, respectively. Phylogenetic analysis was carried out by sequencing the mgc2 and vlhA genes of 2 samples of MG and 24 samples of M. synoviae to gain insight into the genetic variability of Indian strains. The data were then compared with other Indian strains, vaccines strains, and strains from other countries. Results: Our data shows the percent positivity of MG, MS, and co-infection of both MG and MS was 6.43%, 23.61%, and 15.49%, respectively. The phylogenetic relationship between MG and MS was determined using the vlhA and mgc2 genes, revealing two samples of MG and 24 samples of MS clustered with other Indian strains. M. synoviae MSM22 and previously studied M. synoviae MGS 482 clustered with vaccine strain M. synoviae MS-H. Conclusion: Mycoplasma synoviae infections in breeder, layer, and in both is predominant compared to MG across the states investigated in India. Sequenced samples of MG and MS showed evolutionary relationships with the previously studied Indian strains of MG and MS. These findings support our view that monitoring chickens for avian mycoplasma infections are of paramount significance. It further lends credence to the contention that such information will pave the way for the development of a home-grown vaccination control program and thus safeguard the poultry sector against mycoplasma infections.

A conversion‐chemistry‐based zinc–selenium aqueous battery is reported that delivers high specific capacity, good rate capability, and excellent cycle life. In this work, an electronically conjugated covalent triazine framework is used to physicochemically lock selenium (Se8) clusters. As a control sample, the traditional melt‐diffusion approach is used to physically lock Se8. While the melt‐diffused selenium cathode exhibited a precipitous drop in capacity with cycling, the physicochemically locked selenium cathode can be cycled in a stable manner and delivered a specific capacity of ≈600 mAh g−1 with a capacity retention of ≈70% after 1000 continuous charge/discharge steps. Ab initio density functional theory calculations and various structural and morphological characterizations indicate that the superiority of the physicochemically locked selenium cathode stems from its ability to suppress the polyselenide shuttle phenomenon and thus prevent loss of active material during cycling. This work opens the door toward the development of conversion chemistries for high performing, non‐flammable, and low‐cost zinc‐based rechargeable batteries. [ABSTRACT FROM AUTHOR]

Among intercalation, alloying, and conversion battery chemistries, the intercalation chemistry is most widely used in commercial applications due to its superior reversibility, round trip efficiency, and stability, albeit at the expense of reduced specific capacity. While intercalation hosts for monovalent ions (e.g., lithium and sodium) are well developed, the jury is still out on the best available intercalation host materials for multivalent ions such as magnesium, zinc, calcium, and aluminum. In multivalent systems, it is challenging to find electrode materials that can act as a durable host, and accommodate large number of ions, while also permitting fast diffusion kinetics. In this perspective, the electrochemical performance of five distinct class of materials (prussian blue analogues, sodium super ionic conductors, organic, layered, and open‐tunnel oxides) for multivalent ion storage is evaluated. The analysis reveals that open‐tunnel oxides show noticeably superior performance in multivalent ion batteries. Herein, the underlying reasons for this are discussed and the case is made for an in‐depth machine‐learning‐driven “materials exploration effort” directed toward discovery of new open‐tunneled oxides that could lead to vastly superior multivalent ion batteries.

Abstract Swift heavy ions (SHI) irradiation of Nickel (Ni) beam with different ions fluence bring the modifications in the functional properties of radio frequency (RF) grown zirconium oxide (ZrO2) nanocrystalline thin films. X-ray diffraction analysis affirms the monoclinic to tetragonal phase transformation and diminishing of peak at higher fluence 1 × 1014 and 2 × 1014 ions/cm2 induced by electronic excitation caused by SHI. Zirconium oxide thin films exhibit the same thickness (195 nm) of virgin and irradiated samples and whereas the nanocrystalline thin films have the elemental composition in proper stoichiometry (1:2) as analyzed by rutherford backscattering spectroscopy (RBS). Photoluminescence measurements confirm the blue emission of virgin and irradiated sample recorded at excitation wavelength 270 to 310 nm. The intensity of obtained emission bands varies with fluence which is interpreted in terms of generation and annihilation of defect centers. The characteristic Ag and Bg Raman modes of monoclinic and tetragonal ZrO2 are obtained at different positions. Moreover, the nanocrystalline ZrO2 thin films exhibits the most prominent absorption phenomenon in the visible range and the irradiation cause significant decrease in band gap to 3.69 eV compare to the virgin ZrO2 sample (3.86 eV). XPS analysis indicates the shifting of the core levels Zr 3d and O 1s towards higher binding energy and spin—orbit splitting of different states. The findings in this research justify that the irradiated thin films can be a potential candidate for designing of new materials, intense radiation environments, nuclear reactors, nuclear waste systems, clean energy sources.

High Li‐storage‐capacity particles such as alloying‐based anodes (Si, Sn, Ge, etc.) are core components for next‐generation Li‐ion batteries (LIBs) but are crippled by their intrinsic volume expansion issues. While pore pre‐plantation represents a mainstream solution, seldom do this strategy fully satisfy the requirements in practical LIBs. One prominent issue is that porous particles reduce electrode density and negate volumetric performance (Wh L−1) despite aggressive electrode densification strategies. Moreover, the additional liquid electrolyte dosage resulting from porosity increase is rarely noticed, which has a significant negative impact on cell gravimetric energy density (Wh kg−1). Here, the concept of judicious porosity control is introduced to recalibrate existing particle design principles in order to concurrently boost gravimetric and volumetric performance, while also maintaining the battery's cycle life. The critical is emphasized but often neglected role that intraparticle pores play in dictating battery performance, and also highlight the superiority of closed pores over the open pores that are more commonly referred to in the literature. While the analysis and case studies focus on silicon‐carbon composites, the overall conclusions apply to the broad class of alloying anode chemistries. [ABSTRACT FROM AUTHOR]

Background and Aim: Cattle are the main reservoir of Escherichia coli O157:H7 and other verotoxigenic E. coli (VTEC); therefore, there is an increased risk of infection to humans by either direct or indirect mode of transmissions. However, the prevalence of E. coli O157:H7 in the healthy cattle population of India is yet to be ascertained. This study aimed to screen the dairy cattle in and around Pune, Maharashtra, India, for verotoxin-producing E. coli O157:H7. Materials and Methods: A total of 257 rectal swabs were collected from 15 different organized and unorganized dairy farms of Pune during the period, January-March 2015. The screening involved enrichment in EC broth followed by differential identification on MacConkey sorbitol agar. The presumptive positive isolates were further confirmed by multiplex polymerase chain reaction (PCR) using primers specific to rfbE (O157), fliC (H7), VT1 (MK1), and VT2 (MK2). Vero-toxicity and antibiotic sensitivity were examined in PCR confirmed isolates. Results: Out of the 257 samples analyzed, 1.9% (2/105) were positive for O157:H7 and 39% (41/105) were positive for VTEC. Two PCR confirmed positive O157:H7 strains and two randomly selected PCR-positive VT strains exhibited in vitro cytopathic effect on Vero cells on day-7 post-inoculation. Antibiotic sensitivity profiling of O157:H7 strains exhibited resistance against penicillin G, kanamycin, ampicillin, tetracycline, gentamycin, cefotaxime, streptomycin, and piperacillin. Conclusion: These findings reveal the presence of pathogenic E. coli O157:H7 in the healthy cattle of Pune; in a situation, wherein regular surveillance for O157:H7 is not a norm. Therefore, the findings presented herein warrant routine surveillance and public awareness to prevent the transfer of such pathogens and manage health risks to the public.

Driven by the cost and scarcity of Lithium resources, it is imperative to explore alternative battery chemistries such as those based on Aluminum (Al). One of the key challenges associated with the development of Al-ion batteries is the limited choice of cathode materials. In this work, we explore an open-tunnel framework-based oxide (Mo3VOx) as a cathode in an Al-ion battery. The orthorhombic phase of molybdenum vanadium oxide (o-MVO) has been tested previously in Al-ion batteries but has shown poor coulombic efficiency and rapid capacity fade. Our results for o-MVO are consistent with the literature. However, when we explored the trigonal polymorph of MVO (t-MVO), we observe stable cycling performance with much improved coulombic efficiency. At a charge–discharge rate of ~0.4C, a specific capacity of ~190 mAh g−1 was obtained, and at a higher rate of 1C, a specific capacity of ~116 mAh g−1 was achieved. We show that differences in synthesis conditions of t-MVO and o-MVO result in significantly higher residual moisture in o-MVO, which can explain its poor reversibility and coulombic efficiency due to undesirable water interactions with the ionic liquid electrolyte. We also highlight the working mechanism of MVO || AlCl3–[BMIm]Cl || Al to be different than reported previously.

The electrochemical performance of supercapacitors drops precipitously at extreme low temperatures due to a multitude of reasons, which includes electrolyte freezing, sluggish ion transport in the electrode and electrolyte, and high charge transfer resistance at electrode–electrolyte interfaces. To address high interface resistance, a new supercapacitor architecture is reported, in which MXene/carbon nanotube electrodes with vertically aligned channels are synthesized to reduce tortuosity and maximize the electrode–electrolyte contact area. These electrodes are fabricated using a directional‐freezing strategy, generating direct and fast ion transport pathways. Further, a freeze‐resistant electrolyte which shows high ionic conductivity is synthesized by designing a double‐crosslinked polymer network in a binary solvent consisting of ionic liquid and water, which exhibits an ultralow freezing temperature of −54 °C. An all‐in‐one supercapacitor is assembled by an integrated polymerization strategy to minimize interfacial resistances. The resulting device delivers a specific capacitance of 231 F g−1 at 2 mV s−1 and a maximum energy density of 10.17 Wh kg−1, while maintaining a capacitance retention of 92%, even at an extreme low temperature of −50 °C. The supercapacitor architecture developed in this study, demonstrates the feasibility of electrochemical energy storage at extreme low temperatures. [ABSTRACT FROM AUTHOR]

VS2 is a promising cathode material for lithium-ion batteries, but is susceptible to Peierls distortion during (de)lithiation. Here the authors show that VS2 cathodes can be stabilized by conformally coating them with a nanoscale TiS2 protective layer, leading to impressive electrochemical performance.