Microbial species exhibit sophisticated interdependencies as strategies to coexist in communities. Human health and disease are critically dependent on the compositions and structures of these ...communities. Unraveling the underlying interdependencies would help engineer natural and synthetic microbial communities, central to modern food and healthcare applications. Here, we constructed a synthetic microbial community of seven naturally co-occurring oral bacteria and employed a bottom-up approach to understand the role of interspecies interactions in deciding the structure of this community. In particular, we focused on the abundance of the species Actinomyces viscosus, implicated in the virulence of oral microbial biofilms and dental caries. The community showed strong evidence of fifth-order interactions. The abundance of A. viscosus was high in monoculture, low in the presence of some but not all of the other species, and high again in the seven-species community. To understand these interactions, we investigated the influence of the various species in different combinations on A. viscosus. Two species, Streptococcus mitis and Lactobacillus casei, individually strongly suppressed A. viscosus. This suppression could not be reversed by any of the other species in all possible combinations, except when they were all simultaneously present. Thus, the need for the simultaneous presence of the remaining four species to overcome the influence of S. mitis and L. casei on A. viscosus implied that the seven-species community structure was due to a fifth-order interaction that eclipsed the pairwise interactions. We employed a generalized Lotka–Volterra model to quantify these interactions. The interactions captured the structure of a new community containing the seven species and an additional species, validating the model and presenting the high-order interaction as a handle to tune the community structure. Overall, our study demonstrates the existence of high-order interactions that could define the structure of multispecies microbial communities.
ZnO nanopowders doped with cerium ions (1.2 and 1.5 at. wt.%) were synthesized through soft solution route using ultrasound. Sonication has been found to be an effective way for doping rare earth ...ions like cerium into ZnO. This was confirmed from energy dispersive analysis of X-rays (EDAX) measurement. Further, optical absorption and photoluminescence (PL) measurements corroborate this finding. X-ray diffraction (XRD) studies show the increase of crystallite size and unit cell volume with doping of cerium ions. Formation of fibrous structure of ZnO:Ce was observed from the transmission electron microscopy (TEM) measurements. Although the structural measurements indicate Ce4+ ion occupying substitutional site in ZnO, PL and absorption studies confirmed the presence of Ce3+ ion in the powder. The coexistence of Ce3+ and Ce4+ ions has been explained on the basis of conversion of Ce3+ to Ce4+ in the oxidizing environment. Thermoluminescence (TL) and photo-stimulated decay of luminescence (PSDL) decay studies give an idea of various trapping levels present in the band gap of ZnO. These traps release electrons during optical stimulation to give bimolecular kinetics in nano ZnO:Ce powders.
► Sonication: an effective way of incorporation of cerium ions into ZnO. ► Site dependent characteristic emission of cerium. ► Energy transfer from host lattice to cerium ions. ► Mono and bimolecular kinetics of ZnO:Ce.
Free radicals are implicated in causation of cerebral reperfusion injury and chronic cerebral hypoperfusion in rats is associated with functional and histopathological disturbances.
Ocimum sanctum ...(OS), a plant widely used in Ayurveda, has been shown to possess anti-inflammatory, antioxidant and cognition-enhancing properties. In the present study, we investigated the effect of methanolic extract of OS leaves in cerebral reperfusion injury as well as long-term hypoperfusion. Occlusion of bilateral common carotid arteries (BCCA) for 30 min followed by 45 min reperfusion caused increase in lipid peroxidation and up-regulation of superoxide dismutase (SOD) activity accompanied by fall in tissue total sulfhydryl groups (TSH) in rat forebrains. Ascorbic acid levels were unchanged, however. OS pretreatment (200 mg/kg/day for 7 days) prevented this reperfusion-induced rise in lipid peroxidation and SOD activity. OS pretreatment also stabilized the levels of TSH during reperfusion. Long-term cerebral hypoperfusion (a model of cerebrovascular insufficiency and dementia) induced by permanent occlusion of BCCA for 15 days demonstrated altered exploratory behavior in open-field testing and memory deficits as tested by Morris' water maze. Histopathological examination of hypoperfused animals revealed reactive changes, like cellular edema, gliosis and perivascular inflammatory infiltrate. OS treatment (200 mg/kg/day for 15 days) significantly prevented these hypoperfusion-induced functional and structural disturbances. The results suggest that OS may be useful in treatment of cerebral reperfusion injury and cerebrovascular insufficiency states.
Gd doped ZnO nanoparticles with varying dopant concentration are synthesized by simple wet chemical method. X-ray diffraction measurements confirm that the prepared samples are of hexagonal wurtzite ...structure with grain size around 50-60 nm. Gd doping induces lattice expansion in ZnO as the average crystallite size increases with the evolution of Gd2O3 phase after Gd doping. Electron microscopic studies show the presence of two types of particle distribution belonging to ZnO and Gd2O3 phases with an average size of 55 nm where the later surrounds the surface of ZnO. UV-VIS spectra show red-shift of absorption band of ZnO with Gd doping. A suppression of band edge UV emission and intensification of visible emission is observed in the photoluminescence spectra of doped ZnO. This has been explained on the basis of incorporation of impurity levels by the dopant along with intrinsic defect such as oxygen vacancies in the band gap of ZnO.
Metaphorical memes, where a source concept is projected into a target concept, are an essential construct in figurative language. In this article, we present a novel approach for downstream learning ...tasks on metaphorical multimodal memes. Our proposed framework replaces traditional methods using metaphor annotations with a metaphor-capturing mechanism. Besides using the significant zero-shot learning capability of state-of-the-art pretrained encoders, this work introduces an alternative external knowledge enhancement strategy based on ChatGPT (chatbot generative pretrained transformer), demonstrating its effectiveness in bridging the intermodal semantic gap. We propose a new concept projection process consisting of three distinct components to capture the intramodal knowledge and intermodal concept gap in the forms of text modality embedding, visual modality embedding, and concept projection embedding. This approach leverages the attention mechanism of the Graph Attention Network for fusing the common aspects of external knowledge related to the knowledge in the text and image modality to implement the concept projection process. Our experimental results demonstrate the superiority of our proposed approach compared to existing methods.
Aims. The nearby (z = 0.031) TeV blazar Mrk 421 was reported to be in a high state of flux activity since November, 2009. We aim to investigate possible changes in the physical parameters of Mrk 421 ...during its high state of activity using multiwavelength data. Methods. We have observed this source in the bright state using the High Altitude GAmma Ray (HAGAR) telescope array at energies above 250 GeV during February 13–19, 2010. Optical, X-ray and γ-ray archival data were also used to obtain the spectral energy distribution and light curves. Results. Mrk 421 was found to undergo one of its brightest flaring episodes on February 17, 2010 by various observations in X-rays and γ-rays. HAGAR observations during February 13–19, 2010 at energies above 250 GeV show an enhancement in the flux level, with a maximum flux of ~7 Crab units being detected on February 17, 2010. We present the spectral energy distributions during this flaring episode and investigate the correlation of the variability in X-ray and γ-ray bands. Conclusions. Our multiwavelength study suggests that the flare detected during February 16 and 17, 2010 may have been caused by a passing shock in the jet.
► Sonication an effective way of size reduction. ► New photoluminescence band due to silver atom in ZnO. ► Lattice contraction due to impurity induction. ► Surface area improvement due to Ag ion on ...the surface.
ZnO powder doped with 0.84 at wt.% of silver has been synthesized through continuous and pulsed mode sonication method. The particle size was found to be 57(±1)
nm and 44(±1)
nm for continuous and pulsed mode powder, respectively. Contraction along ‘
c’ axis has been observed for Ag doped powders. The surface area measured for pulsed mode powder was found to be twice that of continuous mode powder. Photoluminescence spectra of pulsed mode ZnO:Ag powder show new emission band at 608
nm. This has been attributed to silver atoms sitting on the surface of ZnO nano rods. Structure of the nano rods observed in both the samples was found to be different and this has been attributed to the presence of silver on the surface of the nano rods. The structural evolution during the process of sonication has been explained in the light of Ag ion reduction in the local high concentration region during ultrasonication.
Context. In April 2013, the nearby TeV blazar, Mkn 421, showed one of the largest flares in X-rays in the past decade. Aims. We study all multiwavelength data available during MJD 56 392 to 56 403, ...with special emphasis on X-ray data to understand the underlying particle energy distribution. Methods. We studied the correlations between the UV and gamma-ray bands with the X-ray band using the z-transformed discrete correlation function. We modelled the underlying particle energy spectrum with a single population of electrons emitting synchrotron radiation, and statistically fitted the simultaneous time-resolved data from Swift-XRT and NuSTAR. Results. The flux varied rapidly in the X-ray band, with a minimum doubling timescale of 1.69 ± 0.13 h. There were no corresponding flares in UV and gamma-ray bands. The variability in UV and gamma rays was relatively modest with ~8% and ~16%, respectively, and no significant correlation was found with the X-ray light curve. The observed X-ray spectrum shows a clear curvature that can be fit by a log parabolic spectral form. This is best explained as originating from a log parabolic electron spectrum. However, a broken power law or a power law with an exponentially falling electron distribution cannot be ruled out either. Moreover, the excellent broadband spectrum from 0.3–79 keV allows us to make predictions of the UV flux. We find that this prediction is compatible with the observed flux during the low state in X-rays. However, during the X-ray flares, depending on the adopted model, the predicted flux is a factor of 2–50 lower than the observed one. This suggests that the X-ray flares are probably caused by a separate population that does not contribute significantly to the radiation at lower energies. Alternatively, the underlying particle spectrum can be much more complex than those explored in this work.
The upcoming 50 kt magnetized iron calorimeter (ICAL) detector at the India-based Neutrino Observatory (INO) is designed to study the atmospheric neutrinos and antineutrinos separately over a wide ...range of energies and path lengths. The primary focus of this experiment is to explore the Earth matter effects by observing the energy and zenith angle dependence of the atmospheric neutrinos in the multi-GeV range. This study will be crucial to address some of the outstanding issues in neutrino oscillation physics, including the fundamental issue of neutrino mass hierarchy. In this document, we present the physics potential of the detector as obtained from realistic detector simulations. We describe the simulation framework, the neutrino interactions in the detector, and the expected response of the detector to particles traversing it. The ICAL detector can determine the energy and direction of the muons to a high precision, and in addition, its sensitivity to multi-GeV hadrons increases its physics reach substantially. Its charge identification capability, and hence its ability to distinguish neutrinos from antineutrinos, makes it an efficient detector for determining the neutrino mass hierarchy. In this report, we outline the analyses carried out for the determination of neutrino mass hierarchy and precision measurements of atmospheric neutrino mixing parameters at ICAL, and give the expected physics reach of the detector with 10 years of runtime. We also explore the potential of ICAL for probing new physics scenarios like CPT violation and the presence of magnetic monopoles.
To provide a population-based estimate of the incidence of herpes zoster ophthalmicus (HZO) with comparisons across racial, sex, and age groups, as well as to estimate the frequency of postherpetic ...neuralgia (PHN).
Retrospective, population-based cohort study.
All patients enrolled in the Kaiser Permanente Hawaii health plan during the study period (N = 217 061).
All patient encounters between January 1, 2006, and December 31, 2007, in the electronic medical record of Kaiser Permanente Hawaii were queried for International Classification of Diseases, 9th edition (ICD-9) codes corresponding to HZO. Charts were reviewed to confirm a diagnosis of HZO and to collect information about specific ocular manifestations. Demographic data and information on PHN were collected electronically. Incidence rates were calculated per 100 000 person-years for the entire population and for age-, sex-, and race-specific subgroups.
Clinical diagnosis of HZO during the study period.
A total of 134 cases of HZO were identified in this population of 217 061 people. The overall incidence was 30.9 per 100 000 person-years (95% confidence interval CI, 25.9-36.6). The incidence rate for the population aged ≥65 years was 104.6 per 100 000 person-years (95% CI, 79.0-135.9), approximately 5 times the remainder of the population (P < 0.001). The most common manifestation of HZO was dermatitis, followed by keratitis and conjunctivitis. The incidence of HZO for Pacific Islanders was 19.0 per 100 000 person-years (95% CI, 12.4-28.3), which was significantly lower than the rate for non-Pacific Islanders (P = 0.007). Twenty-one percent of patients with HZO developed PHN. Older age and HZO with keratitis, conjunctivitis, or uveitis were found to be risk factors for PHN.
This study provides a population-based estimate of HZO and highlights differences across various age and racial groups. It also suggests that demographic characteristics may be useful in determining the risk of developing HZO.
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