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The anion C5N− is one of the largest linear (C,N)-bearing chains detected in the interstellar medium. Here we present and discuss the general features of new ab initio potential energy surfaces describing the interaction of this linear anion with He and H2. We employ a Legendre Polynomials expansion representation for the former and an artificial neural network fit for the latter. We then carry out quantum scattering calculations to yield rotationally inelastic cross-sections for collisions with He and H2, using relative translational energy values in the range of 0.1–300 cm−1. We then obtained the corresponding inelastic rate coefficients as a function of temperature covering the range from 1 to 100 K. The results for these two systems are compared with each other, as well as with the earlier results on the C3N− colliding with the same partners. We found that the final inelastic rate coefficients for this anion are all fairly large, those from collisions with H2 being the largest. The consequences of such findings on their non-equilibrium rotational populations in interstellar environments are discussed in our conclusions. [ABSTRACT FROM AUTHOR]

The anion C5N− is one of the largest linear (C,N)-bearing chains detected in the interstellar medium. Here we present and discuss the general features of new ab initio potential energy surfaces describing the interaction of this linear anion with He and H2. We employ a Legendre Polynomials expansion representation for the former and an artificial neural network fit for the latter. We then carry out quantum scattering calculations to yield rotationally inelastic cross-sections for collisions with He and H2, using relative translational energy values in the range of 0.1–300 cm−1. We then obtained the corresponding inelastic rate coefficients as a function of temperature covering the range from 1 to 100 K. The results for these two systems are compared with each other, as well as with the earlier results on the C3N− colliding with the same partners. We found that the final inelastic rate coefficients for this anion are all fairly large, those from collisions with H2 being the largest. The consequences of such findings on their non-equilibrium rotational populations in interstellar environments are discussed in our conclusions. [ABSTRACT FROM AUTHOR]

Biofilm development in Pseudomonas aeruginosa is regulated by its quorum sensing (QS) systems. It has three major QS systems: LasI/R, RhlI/R and PQS/MvfR. Previous studies showed that phenyllactic acid (PLA) binds to RhlR and PqsR and inhibits the Rhl and PQS QS; and eugenol at sublethal concentration inhibits Las and PQS QS systems. Here, we have demonstrated that a combination of sublethal doses of eugenol and PLA enhanced the inhibition of the QS mediated production of the virulence factors and biofilm development of this pathogen. A combination of 50 μmol l−1 eugenol and 0·3 mmol l−1 PLA significantly inhibited the pyocyanin production, protease activity, swarming motility and cytotoxic activities of P. aeruginosa strain PAO1, whereas eugenol and PLA when added individually to PAO1 cultures were less effective in inhibiting its virulence factor expression. Biofilm formation of PAO1 was reduced by 32, 19 and 87% on glass surfaces; and 54, 49 and 93% on catheter surfaces when treated using 50 μmol l−1 eugenol or 0·3 mmol l−1 PLA and their combinations, respectively. The in vitro finding in the reduction of biofilm development was further validated in vivo using a catheter associated medaka fish biofilm model. Our results indicate that a combination of QS inhibitors targeting different QS pathways should be selected while designing therapeutic molecules to achieve maximum QS mediated biofilm inhibition and clinical outcome against P. aeruginosa. [ABSTRACT FROM AUTHOR]

Type Ia supernovae (SNe Ia) in the nearby Hubble flow are excellent distance indicators in cosmology. The Zwicky Transient Facility (ZTF) has observed a large sample of SNe from an untargeted, rolling survey, reaching 20.8, 20.6, and 20.3 mag in g r , and i band, respectively. With an FoV of 47 deg2, ZTF discovered > 3000 SNe Ia in a little over 2.5 yr. Here, we report on the sample of 761 spectroscopically classified SNe Ia from the first year of operations (DR1). The sample has a median redshift |$\bar{z} =$| 0.057, nearly a factor of 2 higher than the current low- z sample. Our sample has a total of 934 spectra, of which 632 were obtained with the robotic SEDm on Palomar P60. We assess the potential for precision cosmology for a total of 305 SNe with redshifts from host galaxy spectra. The sample is already comparable in size to the entire combined literature low- z anchor sample. The median first detection is 13.5 d before maximum light, about 10 d earlier than the median in the literature. Furthermore, six SNe from our sample are at D L < 80 Mpc, for which host galaxy distances can be obtained in the JAMES WEBB SPACE TELESCOPE era, such that we have calibrator and Hubble flow SNe observed with the same instrument. In the entire duration of ZTF-I, we have observed nearly 50 SNe for which we can obtain calibrator distances, key for per cent level distance scale measurements. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus, an opportunistic pathogen, causes diverse community and nosocomial‐acquired human infections, including folliculitis, impetigo, sepsis, septic arthritis, endocarditis, osteomyelitis, implant‐associated biofilm infections and contagious mastitis in cattle. In recent days, both methicillin‐sensitive and methicillin‐resistant S. aureus infections have increased. Highly effective anti‐staphylococcal agents are urgently required. Lysostaphin is a 27 kDa zinc metallo antimicrobial lytic enzyme that is produced by Staphylococcus simulans biovar staphylolyticus and was first discovered in the 1960s. Lysostaphin is highly active against S. aureus strains irrespective of their drug‐resistant patterns with a minimum inhibitory concentration of ranges between 0·001 and 0·064 μg ml−1. Lysostaphin has activity against both dividing and non‐dividing S. aureus cells; and can seep through the extracellular matrix to kill the biofilm embedded S. aureus. In spite of having excellent anti‐staphylococcal activity, its clinical application is hindered because of its immunogenicity and reduced bio‐availability. Extensive research with lysostaphin lead to the development of several engineered lysostaphin derivatives with reduced immunogenicity and increased serum half‐life. Therapeutic efficacy of both native and engineered lysostaphin derivatives was studied by several research groups. This review provides an overview of the therapeutic applications of native and engineered lysostaphin derivatives developed to eradicate S. aureus infections. [ABSTRACT FROM AUTHOR]

Candida species are opportunistic human fungal pathogens that cause acute and chronic infections against which only few antifungal agents are available. Here we have elucidated the antifungal effect of Syzygium samarangense leaf extracts (SSLE). Antifungal activity of SSLE was studied against Candida albicans, C. krusei, C. parapsilosis, C. glabrata, C. auris and C. tropicalis. Following experiments were performed: minimum fungicidal concentration (MFC) determination, agar well disc diffusion assays, fungal morphology analysis using scanning electron microscope (SEM), ex vivo fungal survival assays on porcine tongue and skin and in vivo fungal survival assays using Drosophila melanogaster fly model. Results demonstrated MFC of SSLE ranges between 100 and 125 mg ml−1. SEM images showed cell wall degradation of C. albicans when treated with SSLE. Around 75% decrease in C. albicans viability was observed when infected porcine tongue and skin were treated using SSLE. The C. albicans infected D. melanogaster when fed with SSLE showed significant decrease (around 80%) of fungal count than the infected control. Furthermore, agar plate disc diffusion assays demonstrated that the antifungal activity of SSLE could be due to chalcone, which is one of the active constituents in SSLE. Our study demonstrated that SSLE could be used for the topical treatment of Candida infections. [ABSTRACT FROM AUTHOR]

Aim: The effect of anacardic acid impregnation on catheter surfaces for the prevention of Staphylococcus aureus attachments and biofilm formations were evaluated. Methods and Results: Silicon catheter tubes were impregnated using different concentrations of anacardic acids (0·002–0·25%). Anacardic acids are antibacterial phenolic lipids from cashew nut (Anacardium occidentale) shell oil. Anacardic acid‐impregnated silicon catheters revealed no significant haemolytic activity and were cytocompatible against fibroblast cell line (L929). Sustained release of anacardic acids was observed for 4 days. Anacardic acid‐impregnated silicon catheters efficiently inhibited S. aureus colonization and the biofilm formation on its surface. The in vivo antibiofilm activity of anacardic acid‐impregnated catheters was tested in an intraperitoneal catheter‐associated medaka fish infection model. Significant reduction in S. aureus colonization on anacardic acid‐impregnated catheter tubes was observed. Conclusions: Our data suggest that anacardic acid‐impregnated silicon catheters may help in preventing catheter‐related staphylococcal infections. Significance and Impact of the Study: This study opens new directions for designing antimicrobial phytochemical‐coated surfaces with ideal antibiofilm properties and could be of great interest for biomedical research scientists. [ABSTRACT FROM AUTHOR]

Nano-CaF2, prepared by the co-precipitation method, was annealed under different annealing conditions to improve its thermoluminescence (TL) characteristics. Different annealing parameters, such as temperature (400–700°C), duration (1–4 h) and environment (vacuum and air), were explored. The effect on TL sensitivity, peak position (Tm) and full-width at half-maximum (FWHM) with respect to the different annealing conditions are discussed as they are the measure of crystallinity of the material. Annealing temperature of 500°C with annealing duration of two and a half hours in vacuum provided the highest luminescence response (i.e. maximum sensitivity, minimum peak temperature and FWHM). Wide detectable dose range (5 mGy to 2 kGy), absence of thermal quenching and sufficient activation energy (1.04 eV) of this phosphor make it suitable for dosimetric applications. [ABSTRACT FROM AUTHOR]

We present DES13S2cmm, the first spectroscopically-confirmed superluminous supernova (SLSN) from the Dark Energy Survey (DES). We briefly discuss the data and search algorithm used to find this event in the first year of DES operations, and outline the spectroscopic data obtained from the European Southern Observatory (ESO) Very Large Telescope to confirm its redshift (z = 0.663 ± 0.001 based on the host-galaxy emission lines) and likely spectral type (Type I). Using this redshift, we find MUpeak=-21.05+-0.090.10 for the peak, rest-frame U-band absolute magnitude, and find DES13S2cmm to be located in a faint, low-metallicity (sub-solar), low stellar-mass host galaxy (log (M/MΘ) = 9.3 ± 0.3), consistent with what is seen for other SLSNe-I. We compare the bolometric light curve of DES13S2cmm to 14 similarly well-observed SLSNe-I in the literature and find that it possesses one of the slowest declining tails (beyond +30 d rest-frame past peak), and is the faintest at peak. Moreover, we find the bolometric light curves of all SLSNe-I studied herein possess a dispersion of only 0.2-0.3 mag between +25 and +30 d after peak (rest frame) depending on redshift range studied; this could be important for 'standardizing' such supernovae, as is done with the more common Type Ia. We fit the bolometric light curve of DES13S2cmm with two competing models for SLSNe-I - the radioactive decay of 56Ni, and a magnetar - and find that while the magnetar is formally a better fit, neither model provides a compelling match to the data. Although we are unable to conclusively differentiate between these two physical models for this particular SLSN-I, further DES observations of more SLSNe-I should break this degeneracy, especially if the light curves of SLSNe-I can be observed beyond 100 d in the rest frame of the supernova. [ABSTRACT FROM AUTHOR]

Salmonella spp. has the capability to form biofilm on various surfaces. Biofilm-associated protein (bapA), a large surface protein has been shown to play a leading role in the development of biofilm in Salmonella. Objective of this study was to investigate the presence of bapA gene in different serotypes of Salmonella spp. and to characterize DNA fragment encoding bapA protein of Salmonella Enteritidis. Sixty-seven Salmonella strains belonging to 34 serovars isolated from diverse sources in India were screened for the presence of bapA gene employing a primer designed for the purpose. All the strains yielded a positive amplification indicating that the bapA gene is well conserved in Salmonella spp. The amplified gene fragment of bapA was cloned in Escherichia coli (DH5 α) cells by using pGEM-T easy cloning vector. On partial sequence analysis, the product exhibited 667 base pairs, corresponding to 218 amino acids. BapA gene was found to be highly conserved in Salmonella. Partial sequence analysis of this gene from a strain of Salm. Enteritidis revealed close association with serotypes of poultry origin and also with some other animal/zoonotic serotypes. BapA gene can be targeted for the genus-specific detection of this organism from different sources. Antigenic index of bapA protein indicates its protective and diagnostic potentials. [ABSTRACT FROM AUTHOR]