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Intro: Urinary tract infection (UTI) is one of the most common infections in children. Escherichia coli is the predominant organism causing UTI. The emergence of ESBL+ve E.coli harbouring other resistance genes poses a major challenge to clinicians. Though antimicrobial resistance (AMR) is of global concern, gathering local data in community-settings cannot be overemphasized. It is prudent to have knowledge about the genome of ESBL+ve E.coli at the country level to mitigate the risk in near future. Methods: Children (2-18 years) having UTI symptoms for less than a week in community health centres of Delhi, Bangalore, Jodhpur and Bhubaneswar representing north, south, west and east India were enrolled from 2019-2021. Phenotypic identification and antimicrobial susceptibility testing of the isolates causing significant bacteriuria was performed using MALDI-TOF and VITEK 2. Nineteen ESBL+ve E. coli isolates were analyzed by whole genome sequencing. Findings: 9.1% (42/461) of children were positive causing significant bacteriuria. [M:F 1:1, > 50% > 10 years]. E.coli was the predominant uropathogen (83.3%, 35/42) followed by Klebsiella pneumoniae (12%, 5/42), and Proteus spp. (4.7%, 2/42). Sixty percent of the E.coli isolates were ESBL producers. Genome sequence of the ESBL+ve E.coli was observed to carry large number of AMR genes such as blaNDM-5, blaOxa-1, blaCTX-M-15/14, AmpC, AAC(3)-IIa/IIc/Ib and others. ST131phylogroup was the most prevalent. Plasmid IncFIB and IncFIA found in more than 50% isolates. Composite transposon, IS26 was found in many isolates carrying blaOxa-1, blaNDM-5, blaCTX-M-15/14, blaTEM, aac(3′)-lb with at least 98% identity and coverage. Conclusion: Our data represents a large-scale nationwide community study among children indicating ESBL+ve E.coli isolates harbouring multidrug-resistant genes with high-risk clones. There is an urgent need for augmented surveillance at the local level for the recent knowledge of AMR patterns in the community; thereby preventing the imminent threat of an epidemic of AMR in near future.

Intro: In an unfavorable environment, bacteria improvise living strategy by ceasing growth and reducing metabolism to attain Viable But Non-Culturable (VBNC) state. Once these bacteria find a favorable environment, they resume growth process. In the last few decades, researchers have demonstrated that several human pathogens can attain VBNC state after exposure to several physical and chemical conditions. Due to low metabolism and non-culturability, VBNC escapes culture-based detection. Pieces of evidence are there to indicate emergence of new mutations and AMR phenotypes in VBNC and resuscitated states. Commonly used antibiotics, ciprofloxacin, amoxicillin and FDA-approved surface disinfectant Glutaraldehyde have not been tested for VBNC induction. We hypothesized that these xenobiotics can induce VBNC in bacterial species commonly found in hospital environments putatively driving emergence of AMR. This knowledge will help in improving pathogen detection, and infection and AMR control. Methods: Ciprofloxacin, Amoxicillin and Glutaraldehyde were demonstrated to induce VBNC in Klebsiella pneumoniae, Acinetobacter baumannii and Escherichia coli. VBNC induction was validated by CFU count, energy production, membrane integrity and basal metabolism. Confocal microscope for morphology visualizaion, disk diffusion for AST phynotype. Findings: All three xenobiotics induced VBNC state in ∼ 85% of cells in the bacterial population, leaving the rest 15% non-viable, and successfully resuscitated by removing the xenobiotic. The resuscitation started after 24 hours to 48 hours in various conditions and showed increased AMR phenotype. The microscopic visualization showed shrunken but elongated morphology in VBNC as well as resuscitated cells. Conclusion: Our study demonstrated that commonly used antibiotics and surface disinfectant can induce VBNC, which in turn poses a highly probable risk of missing surface microbial contamination in hospital settings. Also, the emergence of new AMR traits due to exposure to these xenobiotics indicates the necessity of further insights into the mechanism of VBNC induction and resuscitation at molecular level and development of safer alternative antimicrobial agents

Intro: Klebsiella pneumoniae causes wide range of infections including urinary tract infections, sepsis, bacteremia, pneumonia and liver abscesses. The emergence of multi drug resistance in this bacterium led to a major setback for clinical management. WHO also endorsed need for finding alternative therapy to antibiotics for the treatment of these infections. Development of vaccines and passive antibody therapy has been proven as a potent alternative to antibiotics in case of MDR, XDR and PDR Klebsiella infections. Methods: Antigen isolation, characterisation and identification through ultracentrifugation, SDS-PAGE and Triple-TOF Mass spectrometry. Cloning and expression of Fep A gene was done. Mice immunisation and challenge study with Klebsiella pneumoniae bacteria accomplished. Findings: Clinical strains of Klebsiella pneumoniae were grown in iron deficient conditions and the iron regulated outer membrane proteins were extracted and characterized through mass spectrometry for specific identification. The gene for identified protein was cloned in pET- 28a vector and expressed in E. coli. The native protein and the recombinant protein were isolated and purified and used as antigens for generation of immune response in BALB/c mice. The native protein of Klebsiella pneumoniae grown in iron deficient condition was identified as FepA (Ferrienterobactin receptor) and other siderophore receptors. This 80 kDa protein generated a significant immune response in BALB/c mice. The antiserum from mice after subsequent booster doses was collected and showed binding with FepA protein in western blot and phagocytic uptake assay of K. pneumoniae. From animal studies after bacterial challenge post immunisation in mice, signifant bacterial clearance was observed. The antiserum from mice showed binding and clearance of the Klebsiella pneumoniae bacteria in vitro and in vivo. Conclusion: The antiserum from immunised mice with FepA showed binding and clearance of the Klebsiella pneumoniae bacteria in vitro and in vivo.This study demonstrates the potential signifance of FepA as an immunogen or a therapeutic agent.

The study presents new on/off switchable nanofiber membranes with high sensitivity for detecting Co2+ and Cu2+ ions. The nanofiber membranes were fabricated by electrospinning (ES) the poly[(2-hydroxyethylmethacrylate-co-N-methylolacrylamide)] [poly(HEMA-co-NMA)] copolymer with different quantities of 2,2′-bipyridine-3,3′-diol (BPDO). Poly(HEMA-co-NMA)random copolymers with various molar ratios of the HEMA and NMA monomers were synthesized by free radical polymerization. The HEMA and NMA moieties were specifically selected to promote hydrophilicity and crosslinking reactions, which ultimately support a mechanically stable structure in aqueous media. ES nanofiber membranes S1-0.5, with a HEMA:NMA molar ratio of 77:23 and 0.5 wt% of BPDO showed strong photoluminescence quenching upon exposure to Co2+ and Cu2+ ions at concentrations ranging from 10–7 to 10–4 M. Moreover, the nanofiber membranes exhibited reversibile on/off fluorescence emission properties upon the sequential addition of Cu2+ ions and ethylenediaminetetraacetic acid (EDTA). These results demonstrate a simple fabrication strategy for nanofiber membranes that have the potential to be effective for the real-time sensing of metal ions.

Abstract Band structure tailoring has been a great avenue to achieve the half-metallic electronic ground state in materials. Applying this approach to the full Heusler alloy Fe2TiSn, Cr is introduced systematically at Ti site that conforms to the chemical formula $${\text{Fe}}_{2} {\text{Ti}}_{{1 - x}} {\text{Cr}}_{x}$$ Fe 2 Ti 1 - x Cr x Sn. Compositions so obtained have been investigated for its electronic, magnetic, and electrical transport properties with an aim to observe the half-metallic ferromagnetic ground state, anticipated theoretically for Fe2CrSn. Our experimental study using synchrotron X-ray diffraction reveals that only compositions with $$x \le$$ x ≤ 0.25 yield phase pure L2 $$_1$$ 1 cubic structures. The non-magnetic ground state of Fe2TiSn gets dramatically affected upon inclusion of Cr giving rise to a localized magnetic moment in the background of Ruderman–Kittel–Kasuya–Yosida (RKKY) correlations. The ferromagnetic interactions begin to dominate for x = 0.25 composition. Results of its resistivity and magnetoresistance (MR) measurement point towards a half-metallic ground state. The calculation of exchange coupling parameter, $$\hbox {J}_{{ij}}$$ J ij , and orbital projected density of states that indicate a change in hybridization between 3d and 5p orbital, support the observations made from the study of local crystal structure made using the extended X-ray absorption fine structure spectroscopy. Our findings here highlight an interesting prospect of finding half-metallicity via band structure tailoring for wide application in spintronics devices.

Purpose: To explore the effect of pharmaceutical industry effluent on viability and persistence of microbial population (environmental and clinical) with regard to abundance of AMR genes and induction of Viable but non-Culturable (VBNC) state. Methods & Materials: Settings: Effluent from common effluent treatment plants (CETP),Sample collection: Samples were collected from industrial effluent inlet and river discharge pointSample Definition: CETP receives effluent from different manufacturing units and pharmaceutical industries dealing with small molecule drugs.Chemical and Phenotypical analysis: Chemical analysis of effluent, detection of AMR genes, VBNC induction by effluent and resuscitation, morphological identification of microbial species Results: Chemical analysis- Chemical analysis of samples, showed high level of lead, mercury, some hydrolyzed imidazole and other smaller hydrolyzed fragments.AMR gene detection- AMR genes for the fluoroquinolone, Aminoglycoside, beta-lactamase Class A/B/C/D, Erythromycin, Lincosamide Streptogramin_b, and vancomycin were present in test samples, with highest copy numbers of Macrolide and tetracycline. Sample from river discharge point had multidrug resistant efflux pump genes.VBNC induction and resuscitation- Based on chemical analysis and presence of AMR genes, further analysis of effect of heavy metals in test sample was explored on microbial population. Effluent sample upon ultra-centrifugation followed by ultra-filtration, did not show any microbial growth under normal culture conditions, but showed growth upon co-culture with E. coli. This indicates the presence of bacterial population in the shrunken form in effluent reflecting the VBNC state.Microbial identification- Different bacterial colonies that was observed during resuscitation were analyzed by gram staining. All 44 colonies were categorized into four groups, gram positive cocci (30), gram positive rod (8), gram negative cocci (4) and gram-negative rod (2), while from unfiltered culture it was 46, 12, 11 and 7 respectively. Conclusion: Presence of heavy metals in the industrial effluent generate selection pressure resulting in emergence of AMR traits. Also, heavy metal and imidazole rich effluent can induce VBNC state and persistence of microbial population, which upon attaining favorable condition, can be resuscitated. This work has significant implication in devising future strategies for effluent treatment to minimize environmental pressure and in turn reduce emergence of AMR.

Abstract In the paper, magnetostatic solutions of the Einstein–Maxwell field equations are generated from the gravitational two-soliton solutions of a stationary mass. Using the soliton technique of Belinskii and Zakharov (Sov Phys JETP 48:985, 1978, Sov Phys JETP 50:1, 1979), we construct diagonal two-soliton solutions of Einstein’s gravitational field equations for an axially symmetric stationary space-time and investigate some properties of the generated stationary gravitational metric. Magnetostatic solutions corresponding to the generated stationary gravitational solutions are then constructed using the transformation technique of Das and Chaudhuri (Pramana J Phys 40:277, 1993). The mass and the dipole moment of the source are evaluated. In our analysis we make use of a second transformation (Chaudhuri in Pramana J Phys 58:449, 2002), probably for the first time in the literature, to generate magnetostatic solutions from the stationary gravitational two-soliton solutions which give us simple and straightforward expressions for the mass and the magnetic dipole moment.

Abstract In the paper, we present exact solutions of gravitational field equations for an anisotropic brane with a Bianchi type I universe with perfect fluid having non-vanishing Weyl tensor of the bulk. It is assumed that the thermodynamic pressure bears a linear relation with the energy density. For a particular non-zero value of the pressure the solutions are obtained in an exact analytic form with and without the cosmological constant for a Bianchi type I universe. The relevant physical quantities associated with the evolution of the universe are also derived in the two cases.

A total of 226 numbers of dogs (114 male and 112 female) in and around Kolkata were screened during November 2012 to July 2013 for Babesiosis and out of them 72 animals (31.86%) were found clinically and cytologically positive with higher incidence in female dogs (53.33%) than male (46.68%). Out of 72 positive samples 68 and 4 animals were found infected with small and large form of Babesia spp., respectively. The present study revealed that incidence of Babesiosis according to sex ratio (male: female) was 1: 1.4. Seasonal record indicated that incidence of Babesia was higher in the months of May and June (7.07%) and less in the month of January (0.44%).

In this paper we report a study of the effect of vacuum annealing at 400°C on the properties of normal metal-insulator-superconductor (NIS) tunnel junctions, with manganese doped aluminium (Al:Mn) as the normal metal, aluminum as the superconductor and amorphous aluminum oxide as the tunneling barrier (Al:Mn-AlOx-Al). The annealing treatment improves the stability of the junctions, increases their tunneling resistance and does not have a negative impact on the low-temperature current-voltage characteristics. The measured 1/f resistance noise of the junctions also changes after annealing, in the best case decreasing by over an order of magnitude. All these observations show that annealing is a viable route to improve NIS junction devices after the sample has been fabricated.

Thermomagnetic avalanches in superconducting films propagating extremely fast while forming unpredictable patterns, represent a serious threat for the performance of devices based on such materials. It is shown here that a normal-metal frame surrounding a selected region inside the film area can provide efficient protection from the avalanches during their propagation stage. Protective behavior is confirmed by magneto-optical imaging experiments on NbN films equipped with Cu and Al frames, and also by performing numerical simulations. Experimentally, it is found that while conventional flux creep is not affected by the frames, the dendritic avalanches are partially or fully screened by them. The level of screening depends on the ratio of the sheet conductance of the metal and the superconductor in the resistive state, and for ratios much larger than unity the screening is very efficient.

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