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Geometrically frustrated kagome lattices are raising as novel platforms to engineer correlated topological electron flat bands that are prominent to electronic instabilities. Here, we demonstrate a phonon softening at the kz = π plane in ScV6Sn6. The low energy longitudinal phonon collapses at ~98 K and q = 1 3 1 3 1 2 due to the electron-phonon interaction, without the emergence of long-range charge order which sets in at a different propagation vector qCDW = 1 3 1 3 1 3 . Theoretical calculations corroborate the experimental finding to indicate that the leading instability is located at 1 3 1 3 1 2 of a rather flat mode. We relate the phonon renormalization to the orbital-resolved susceptibility of the trigonal Sn atoms and explain the approximately flat phonon dispersion. Our data report the first example of the collapse of a kagome bosonic mode and promote the 166 compounds of kagomes as primary candidates to explore correlated flat phonon-topological flat electron physics. The recently discovered charge density wave in ScV6Sn6 kagome metal is under intense debate. By using a combination of experimental and theoretical techniques, the authors point to the role of flat phonon mode softening and momentum-dependent electron-phonon coupling in the formation of the charge density wave. [ABSTRACT FROM AUTHOR]

Due to increased energy intensive human activities resulting in accelerated demand for electric power coupled with the occurrence of natural disasters with increased frequency, intensity, and duration, it becomes essential to explore and advance renewable energy technology for the sustainability of the society. To meet the energy demand of the future, more energy resources and energy conversion/harvesting technologies with higher efficiencies are needed. Addressing the problem and providing a radical solution have been attempted in this study. To harvest the renewable energy, among variety of solar cells reported, a composite a-Si/CZTS photovoltaic device has not yet been investigated. The calculated parameters for solar cells based on the new array of layers consisting of a-Si/CZTS are reported in this study. The variation of (i) solar cell efficiency as a function of Cu2ZnSnS4 (CZTS) layer thickness, temperature, acceptor, and donor defect concentration; (ii) variation of the open-circuit current density as a function of temperature, open circuit voltage; (iii) variation of open-circuit voltage as a function of the thickness of the CZTS layer has been determined. There has been no reported study on a-Si/CZTS configuration-based solar cell, analysis of the parameters, and study to address the challenges that imped efficiency of the photovoltaic device and the same has been discussed in this work. The value of the SnO2/a-Si/CZTS solar cells obtained from the simulation is 23.9%. [ABSTRACT FROM AUTHOR]

The recent advancement in cloud computing enabled technologies to offer scalable and elastic computing components at a reduced cost to manage the IT infrastructure organizations effectively. It addresses the cost optimization problem, which arises in the context of traditional web-enabled computing models where bottle-neck conditions arise owing to managing high-scale dynamic clients along with the flexible infrastructure to map heterogeneous/complex data traffic with storage elements associated with appropriate server units. The trend of research evolution has given birth to the conceptualization of cloud computing, which offers storage, infrastructure, and platform as services with a virtualized mechanism to deal with uncertain complex and high-scaled data traffic irrespective of application domains. It has got a wide range of applications starting from health-care to service industries. Hence, it has become de-facto for any digital and information technology (IT) oriented application design and deployment aspects. Managing complex data flow in the context of the cloud is a highly challenging task, and the principle of multi-tenancy has come up as a solution approach to enhance resource sharing among cloud clients with isolated virtualization and application instances with services. The prime agenda here is to reduce the cost of computation and cloudlet handling time. The study introduces a unique load-balancing approach, namely, multi-tenant load balance (MTLBP), to cope with the service-oriented architecture of multi-tenancy in the cloud environment. It also ensures that the end client user can perform their task execution efficiently on the multi-tenant environment. The experimental approach adopts a behavioral traffic analysis, where the formulated approach's performance is compared with the traditional baseline approaches. The outcome obtained for the proposed approach found quite promising in terms of resource utilization and task execution in comparison with the other models. It shows that the formulated MTLBP approach outperforms the baseline approaches with approximately 26.83% when small value cloudlet processing time is concerned and 33.625% when medium volume cloudlet processing time is concerned and approximately 62% when large volume cloudlet handling time is concerned. It is also observed that for small volume cloudlets, MTLBP attains approximately 12.55% performance improvement on average when resource utilization cost is concerned. For medium and large volume cloudlets, it attains approximately the performance improvement of 9.85% and 3.14%, respectively. [ABSTRACT FROM AUTHOR]

Although skin is the primary affected organ in Leprosy, the role of the skin microbiome in its pathogenesis is not well understood. Recent reports have shown that skin of leprosy patients (LP) harbours perturbed microbiota which grants inflammation and disease progression. Herein, we present the results of nested Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis (PCR-DGGE) which was initially performed for investigating the diversity of bacterial communities from lesional skin (LS) and non-lesional skin (NLS) sites of LP (n = 11). Further, we performed comprehensive analysis of 16S rRNA profiles corresponding to skin samples from participants (n = 90) located in two geographical locations i.e. Hyderabad and Miraj in India. The genus Staphylococcus was observed to be one of the representative bacteria characterizing healthy controls (HC; n = 30), which in contrast was underrepresented in skin microbiota of LP. Taxa affiliated to phyla Firmicutes and Proteobacteria were found to be signatures of HC and LS, respectively. Observed diversity level changes, shifts in core microbiota, and community network structure support the evident dysbiosis in normal skin microbiota due to leprosy. Insights obtained indicate the need for exploring skin microbiota modulation as a potential therapeutic option for leprosy. [ABSTRACT FROM AUTHOR]

An axion insulator is a correlated topological phase, which is predicted to arise from the formation of a charge-density wave in a Weyl semimetal1,2—that is, a material in which electrons behave as massless chiral fermions. The accompanying sliding mode in the charge-density-wave phase—the phason—is an axion3,4 and is expected to cause anomalous magnetoelectric transport effects. However, this axionic charge-density wave has not yet been experimentally detected. Here we report the observation of a large positive contribution to the magnetoconductance in the sliding mode of the charge-density-wave Weyl semimetal (TaSe4)2I for collinear electric and magnetic fields. The positive contribution to the magnetoconductance originates from the anomalous axionic contribution of the chiral anomaly to the phason current, and is locked to the parallel alignment of the electric and magnetic fields. By rotating the magnetic field, we show that the angular dependence of the magnetoconductance is consistent with the anomalous transport of an axionic charge-density wave. Our results show that it is possible to find experimental evidence for axions in strongly correlated topological condensed matter systems, which have so far been elusive in any other context.In the charge-density-wave Weyl semimetal (TaSe4)2I, an axion is observed and identified as a sliding mode in the charge-density-wave phase characterized by anomalous magnetoelectric transport effects. [ABSTRACT FROM AUTHOR]

This paper presents studies carried out on amorphous silicon solar panels for electrical power generation in the city of Hassi Messaoud, Ouargla. The electrical power generation has been studied as a function of the amount of irradiation received and the angle of optimum orientation of the solar panels. An optimal angle of 32 degrees is chosen and the amount of solar radiation received is studied. A direct correspondence was observed between the incident solar radiation and the power generated. The maximum variable power is generated between the months of March and October. During the winters, the power generated slows down as the solar radiation available decreases. The power generated by amorphous silicon solar is almost ∼ 20% less than the same generated by the crystalline Silicon solar panels under similar conditions. [ABSTRACT FROM AUTHOR]

A systematic study on the effect of heat treatment on the structural properties of tungsten carbides coatings deposited by RF magnetron sputtering on steel substrate (XC70) was carried out. These coatings were subjected to heat treatment in vacuum at various temperatures ranging from 500 to 1000 °C for 25 min. Structural analysis of the as-deposited and heat-treated coatings was performed by means of X-ray diffraction (XRD) and optical microscopy. The XRD analyses indicated the presence of nanocrystalline grains with (222) preferential orientation. The grain size varied from 8 to 15 nm. The presence of two different phases WC and WC was observed in the coatings heat treated at 1000 °C. The effect of the annealing temperature on the surface morphology of the coatings was studied using optical microscopy. [ABSTRACT FROM AUTHOR]

This paper describes the mathematical model used to determine the amount of solar radiation received on an inclined solar photovoltaic panel. The optimum slope angles for each month, season, and year have also been calculated for a solar photovoltaic panel. The optimization of the procedure to maximize the solar energy collected by the solar panel by varying the tilt angle is also presented. As a first step, the global solar radiation on the horizontal surface of a thermal photovoltaic panel during clear sky is estimated. Thereafter, the Muneer model, which provides the most accurate estimation of the total solar radiation at a given geographical point has been used to determine the optimum collector slope. Also, the Ant Colony Optimization (ACO) algorithm was applied to obtain the optimum tilt angle settings for PV collector to improve the PV collector efficiency. The results show good agreement between calculated and predicted results. Additionally, this paper presents studies carried out on the polycrystalline silicon solar panels for electrical energy generation in the city of Ghardaia. The electrical energy generation has been studied as a function of amount of irradiation received and the angle of optimum orientation of the solar panels. [ABSTRACT FROM AUTHOR]

This paper reports the effect of heat treatment on the electronic activity of grain boundaries of polycrystalline silicon. The results obtained show that for the same concentration of doping, the arsenic doped films are more resistive and have less free carriers than boron doped films. The arsenic atoms have a greater tendency to segregate at the grain boundaries than boron atoms. We also noticed that the heat treatment before implantation reduces the number of trap carriers and the quantity of doping atoms at the grain boundaries. For low doping, the concentration of the free charge carriers improves after the heat treatment by 100 % and 23 % for arsenic and boron doping respectively. [ABSTRACT FROM AUTHOR]

The effect of hydrogen passivation and heat treatments on the electronic activity at grain boundaries in thin films of polysilicon deposited by LP-CVD (Low Pressure Chemical Vapor Deposition) has been studied. The results obtained have shown that the introduction of hydrogen into polysilicon thin films doped with arsenic ions increases the concentration of free carriers, reduces the resistivity and lowers the density of trap states at the grain boundaries. Free carriers concentration improved by almost 10% at the annealing temperature of 1000 °C. In addition, it was found that the effect of hydrogen is much more pronounced for low temperature heat treatment before doping compared to the effect at the higher temperature. Moreover, the increase in free carrier concentration and the decrease in resistivity of polysilicon thin films with the increase in the annealing temperature has been observed. [ABSTRACT FROM AUTHOR]

The chaperonins, GroEL and GroES, are present ubiquitously and provide a paradigm in the understanding of assisted protein folding. Due to its essentiality of function, GroEL exhibits high sequence conservation across species. Complete genome sequencing has shown the occurrence of duplicate or multiple copies of groEL genes in bacteria such as Mycobacterium tuberculosis and Corynebacterium glutamicum. Monophyly of each bacterial clade in the phylogenetic tree generated for the GroEL protein suggests a lineage-specific duplication. The duplicated groEL gene in Actinobacteria is not accompanied by the operonic groES despite the presence of upstream regulatory elements. Our analysis suggests that in these bacteria the duplicated groEL genes have undergone rapid evolution and divergence to function in a GroES-independent manner. Evaluation of multiple sequence alignment demonstrates that the duplicated genes have acquired mutations at functionally significant positions including those involved in substrate binding, ATP binding, and GroES binding and those involved in inter-ring and intra-ring interactions. We propose that the duplicate groEL genes in different bacterial clades have evolved independently to meet specific requirements of each clade. We also propose that the groEL gene, although essential and conserved, accumulates nonconservative substitutions to exhibit structural and functional variations. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

The incomplete branchial fistula is not an uncommon congenital anomaly of branchial apparatus but a complete one is rare. Here we report a case of complete congenital branchial fistula with an internal opening near the tonsillar fossa. [ABSTRACT FROM AUTHOR]

Leprosy is an infectious disease that has predilection in skin and peripheral nerves. Skin has its own microbiome, however it is not extensively studied in Indian leprosy patients. Here, by using next-generation 16S rDNA sequencing, we have attempted to assess the skin associated microbial diversity pertaining to affected and unaffected skin of Indian leprosy patients. A total of 90 skin swab samples were collected from 60 individuals (30 healthy controls, 30 patients) residing in Hyderabad and Miraj, two distinct geographical locations in India to assess the homo/heterogeneity of skin microbial signatures. While a large increase in genus Methylobacterium and Pseudomonas was seen in patients from Miraj and Hyderabad respectively, a considerable decrease in genus Staphylococcus in the leprosy patients (as compared to controls) from both geographical locations was also observed. We expect that, these datasets can not-only provide further interesting insights, but will also help to observe dynamics of microbiome in the diseased state and generate hypotheses to test for skin microbiome transplantation studies in leprosy. Measurement(s) DNA Technology Type(s) DNA sequencing Factor Type(s) experimental condition Sample Characteristic - Organism Homo sapiens Sample Characteristic - Environment microbial community Sample Characteristic - Location India Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.9897089 [ABSTRACT FROM AUTHOR]

Regulation of complement activation in the host cells is mediated primarily by the regulators of complement activation (RCA) family proteins that are formed by tandemly repeating complement control protein (CCP) domains. Functional annotation of these proteins, however, is challenging as contiguous CCP domains are found in proteins with varied functions. Here, by employing an in silico approach, we identify five motifs which are conserved spatially in a specific order in the regulatory CCP domains of known RCA proteins. We report that the presence of these motifs in a specific pattern is sufficient to annotate regulatory domains in RCA proteins. We show that incorporation of the lost motif in the fourth long-homologous repeat (LHR-D) in complement receptor 1 regains its regulatory activity. Additionally, the motif pattern also helped annotate human polydom as a complement regulator. Thus, we propose that the motifs identified here are the determinants of functionality in RCA proteins. Hina Ojha et al. show that the presence of five motifs in a specific pattern in CCP (complement control protein) domains is indicative of functional RCA (regulators of complement activation) proteins. This study suggests that an in silico regulatory RCA prediction tool CoReDo can be used to identify putative regulatory RCA proteins. [ABSTRACT FROM AUTHOR]

In stark contrast to ordinary metals, in materials in which electrons strongly interact with each other or with phonons, electron transport is thought to resemble the flow of viscous fluids. Despite their differences, it is predicted that transport in both conventional and correlated materials is fundamentally limited by the uncertainty principle applied to energy dissipation. Here we report the observation of experimental signatures of hydrodynamic electron flow in the Weyl semimetal tungsten diphosphide. Using thermal and magneto-electric transport experiments, we find indications of the transition from a conventional metallic state at higher temperatures to a hydrodynamic electron fluid below 20 K. The hydrodynamic regime is characterized by a viscosity-induced dependence of the electrical resistivity on the sample width and by a strong violation of the Wiedemann-Franz law. Following the uncertainty principle, both electrical and thermal transport are bound by the quantum indeterminacy, independent of the underlying transport regime. [ABSTRACT FROM AUTHOR]