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In a pursuit to satisfy the rising energy demand, researchers to create novel, environmentally safe electrode materials for several energy storage devices. The electrochemical performance could be compromised as a result of the polymer binders employed in the electrode coating procedure. Binder-free electrode materials accelerate electron transport pathways by providing enough room to accommodate the active material's large volume changes during charging and discharging. Lower electronegativity of sulphur compared to oxygen provides increased flexibility in the structure of transition metal sulphides which makes them stand out as the promising candidates in the search for innovative electrode materials. Likewise, although PANI possess high conductivity and specific capacitance, it's ineffective to be used in the purest form for practical applications owing to its inability to retain the capacitance when it undergoes multiple charging/discharging cycles. In this work, we describe the development of binder-free Cu-Mn mixed sulphide and its nanocomposite with PANI on carbon fibre paper (CP) substrates. Characterization techniques such as XPS, FE-SEM along with elemental mapping helped in understanding the successful formation of the nanocomposite. In contrast to pure PANI and Cu-Mn mixed sulphide at the same current density in a neutral 1 M Na 2 SO 4 electrolyte, the composite of Cu-Mn mixed sulphide and PANI demonstrated an enhanced areal capacitance of 550.95 mF cm−2 at 1 mA cm−2. Incorporating PANI with Cu-Mn mixed sulphides has not only improved their capacitance but also reduced the rate at which pristine PANI's capacitance degrades when subjected to a greater number of charge/discharge cycles which is reflected in the enhanced capacity retention property of the nanocomposite, wherein the composite maintained 99.02% of its original capacitance at a current density of 10 mA cm−2 than of pure PANI on CP substrates. [Display omitted] [ABSTRACT FROM AUTHOR]

In the title compound, C21H17N3O2, the dihedral angles between the central pyrazole and the substituent pyridine, hydroxyphenyl and benzene rings are 48.58 (1), 5.2 (1) and 84.73 (1)°, respectively. [ABSTRACT FROM AUTHOR]

Abstract We have synthesized the titanium dioxide (TiO 2)/graphene nanocomposite with simultaneous N-doping (N-TiO 2 /NG) by one-pot hydrothermal synthesis for energy storage application. X-Ray Diffraction (XRD) patterns, Fourier Transform InfraRed (FTIR) spectroscopy, Field Emission Scanning Electron Microscopy (FESEM) and Raman spectroscopy was done to evaluate the morphology, crystalline structure and functionality of the material. The surface elemental composition and bonding was analysed by X-ray Photoelectron Spectroscopy (XPS), Energy Dispersive Spectroscopy (EDS) and EDS mapping. The N-TiO 2 /NG electrode showed a specific capacitance of 205.1 F g−1 at 1 mV s−1, with good cyclic stability of 78.8%, after 5000 continuous charge/discharge cycle at 1 A g−1, whereas TiO 2 /rGO showed only 67% of retention, which shows its potential for energy storage application. Graphical abstract Unlabelled Image Highlights • Nitrogen doped TiO 2 /Nitrogen doped Graphene (N-TiO 2 /NG) nanocomposite has been synthesized by one step hydrothermal method. • Detail electrochemical studies of the material have been done to find its potential for energy storage application. • N-TiO 2 /NG composite showed superior specific capacitance and better cyclic stability compared to TiO 2 /rGO nanocomposite. [ABSTRACT FROM AUTHOR]

In the title compound, C21H16FN3O2, the pyridine ring is nearly coplanar with the plane of the fused bicyclic ring system [dihedral angle = 4.1 (2)°], while the 4-fluoro­phenyl ring forms a dihedral angle of 67.7 (3)° with the fused bicyclic ring system. [ABSTRACT FROM AUTHOR]

The structure of the title compound, C25H22ClN3O2·C2H6O, displays N—H⋯O, O—H⋯O, O—H⋯N, C—H⋯Cl, C—H⋯O hydrogen bonding. [ABSTRACT FROM AUTHOR]

Development of useful products from toxic or hazardous waste is a unique strategy to overcome their disposal. In this work, we report the valorization of the toxic flowers of Thevetia peruviana (TP) into blue fluorescent nitrogen doped carbon dots (N‐CDs) with ∼6.6 % nitrogen doping from a single source of biomass without using any external dopant. The hydrophilic N‐CDs are biocompatible and show excitation‐dependent emission. Cytotoxity studies revealed the N‐CDs are selectively toxic towards the cancerous cells (DU‐145, MDA MB‐231, HepG2, and B16) but more biocompatible with normal CHO‐K1 and HEK‐293 cells. It has been observed that generation of reactive oxygen species in presence of N‐CDs cause DNA damage and the unrepaired cells undergo apoptosis in G2/M phase. To investigate the toxicity to normal cells, we further carried out in‐vitro and in‐vivo genotoxicity studies to reveal its non‐mitotoxic, non‐clastogenic, and non‐aneugenic properties. [ABSTRACT FROM AUTHOR]

This paper considers the study of the optimality of the extended design generated by adding few runs to an existing E ( χ 2 ) -optimal mixed-level supersaturated design. This paper covers the work of Gupta et al. (2010, 2012) on extended two-level and s -level supersaturated designs as two special cases. A lower bound to E ( χ 2 ) has been obtained for the proposed designs. A small example is presented here attaining the lower bound. [ABSTRACT FROM AUTHOR]

Abstract: An efficient and reusable polyaniline nanofiber supported ferric chloride catalyst was developed and characterized by FT-IR, UV–vis, XPS, TEM and XRD techniques. The catalyst was used in the selective acylation of alcohols and amines employing acetic acid as an acylating agent to obtain the corresponding acetates and acetamides in good to excellent yields. [Copyright &y& Elsevier]

The increasing demand for the development of high-performance supercapacitors led researchers to synthesize and develop new electrode materials by optimizing various parameters. In this respect, we have developed ternary nanocomposites using graphene, CuCr 2 O 4 and polyaniline as potent electrode material. We have used simple sonication-assisted mechanical mixing of pre-synthesized N-doped graphene, CuCr 2 O 4 and polyaniline at varied proportions. The prepared composites have been analyzed by different characterization techniques to comprehend the successful formation of the composite. The electrochemical characterizations revealed that the nanocomposite shows the specific capacitance of 443.4 F g−1 at a current density of 1 A g−1 with excellent capacity retention of 92% even after 10,000 GCD cycles, thereby validating the fact that N-doped graphene and CuCr 2 O 4 have enhanced the stability of pristine PANI. [Display omitted] [ABSTRACT FROM AUTHOR]

Current scenario of energy crisis and recent development of renewable energy resources have triggered a rapid development of energy storage materials for rechargeable metal ion batteries and supercapacitors. In this regard, two dimensional materials like graphene based spinel oxide nanocomposites have great potential for the above purpose. Hetero-atom doping modifies the electronic and electrical properties of conductive materials. Hence, to understand the effect of nitrogen doping on the supercapacitive properties, we have synthesized nitrogen doped graphene (NG)/CuCr 2 O 4 nanocomposites for high-performance supercapacitors with specific capacitance of 530.6 F g−1 at 0.5 A g−1 current density. The composites which have been synthesized using a simple one step sonication-assisted mechanical mixing method using pre-synthesized CuCr 2 O 4 and NG, have scope for scale up. We have noticed the effect of nitrogen doping on coulombic efficiency of the composites, which comes due to the deformed local structures around nitrogen. Image 1 [ABSTRACT FROM AUTHOR]

Abstract The novel chemical composition of pristine Mn 1/3 Ni 1/3 Co 1/3 MoO 4 (MNC) and Mn 1/3 Ni 1/3 Co 1/3 MoO 4 dispersed in various percentages of reduced graphene oxide (MNC/rGO) composites were prepared via the one-step hydrothermal method. X-ray diffraction (XRD) patterns showed pure crystalline phase CoMoO 4 for the heat treated powder at 350 °C. Fourier Transform Infrared (FT-IR) spectra showed that the chemical band structure of Mn 1/3 Ni 1/3 Co 1/3 MoO 4 corresponds to the strong vibrational bands of Mo O, Mo O and Mo O Mo bonds. X-ray photoelectron spectroscopy (XPS) analysis confirmed the presence of Mn, Ni, Co, Mo, C and O elements and its valance in the MNC/rGO powder. Field Emission Scanning Electron Microscope (FE-SEM) images displayed the nanorods morphology of the MNC/rGO powders. High-resolution Transmission Electron Microscopy (HR-TEM) images showed the morphology of MNC nanorods wrapped with the reduced graphene oxide of the MNC/rGO composite. The MNC/rGO composite displayed the highest specific capacitances of 1750 F g−1 at 1 A g−1 in 3 M KOH. The MNC/rGO composite demonstrated a better cycling stability with a cycling efficiency of 85.5% after 5000 cycles at 10 A g−1. The high rate performances, good reversibility and capacity retention at a range of current densities were demonstrated the structural stability of the MNC/rGO composite. The high energy density of 38.8 W h kg−1 at a constant power density of 200 W kg−1was achieved for the MNC/rGO composite. Graphical abstract Image 1 Highlights • Novel composition of Mn 1/3 Ni 1/3 Co 1/3 MoO 4 (MNC)/rGO composite synthesized via a one-step hydrothermal method. • The MNC/rGO composite electrode exhibits specific capacitance of 1750 F g−1 at 1 A g−1. • The cycling stability of the composite electrode at 10 Ag−1 shows 85.5% specific capacitance retention after 5000 cycles. [ABSTRACT FROM AUTHOR]

In this study, we report a novel copper chromite-polyaniline (CuCr 2 O 4 -PANI) nanocomposite electrode material for fabrication of high-performance energy storage. First CuCr 2 O 4 is synthesized via sol-gel driven epoxide method followed by its nanocomposite with PANI through in situ chemical oxidative polymerization method. The micro structure and morphology of CuCr 2 O 4 -PANI are characterized by various techniques. The as synthesized nanocomposite with optimized ratio exhibits a specific capacity of 479.2C g −1 at 2 mV s −1 and high cycling stability with 93.9% capacity retention after 1000 charge-discharge cycles. Furthermore, it shows energy and power densities of 26.6 Wh kg −1 and 3600 W kg −1 , respectively. The change in electrochemical properties of the nanocomposite with increasing CuCr 2 O 4 loading is explained in detail. [ABSTRACT FROM AUTHOR]

In this work, TiO 2 -β-cyclodextrin-graphene nanocomposite (TiO 2 -CD@GNS) has been synthesized by a simple water phase approach at 90 °C. We have used functional properties of β-cyclodextrin to stabilize graphene in aqueous medium which can facilitate the self assembly of in situ grown anatase TiO 2 nanoparticles (TiO 2 NPs) on graphene nanosheets (GNS). This nanocomposite is found to exhibit better energy storage capacity and photocatalytic activity than TiO 2 -reduced graphene oxide (TiO 2 -RGO) composites. 100% photodegradation of methylene blue is observed within 25 min under visible light using TiO 2 -CD@GNS which clearly explains its high photocatalytic activity. This may be due to increased visible light absorption and electron transfer via Ti-O-C between Ti and C which greatly retards the effective recombination of photogenerated electron-hole pairs. For energy storage applications, this material showed its capability of delivering 266.6 Fg −1 capacitance at a scan rate of 1 mVs −1 from cyclic voltammetry and excellent cyclic stability with 90% capacitance retention after 1000 continuous charge/discharge cycles at 1 Ag −1 current density. The capacitance of the TiO 2 -CD@GNS electrode was 20% higher than TiO 2 -RGO electrode (222.9 Fg −1 at 1 mVs −1 ) and 2 times higher than CD@GNS electrode (115.4 Fg −1 at 1 mVs −1 ). This enhanced capacitance was attributed to the charge transfer between electrode-electrolyte interfaces and hydrophilic nature of the composite which enhances wettability of aqueous electrolytes. This may be due to functionalization of graphene and uniform dispersion of small sized (<10 nm) TiO 2 NPs onto CD@GNS surface without agglomeration which brings about supramolecular host-guest interactions. Here, the CD moiety loaded on graphene nanosheets acted as linkers between them and works as stabilizing agent for the TiO 2 NPs to prevent agglomeration. [ABSTRACT FROM AUTHOR]

Abstract: The Protein Data Bank (PDB) was established in 1971 as a repository for the three dimensional structures of biological macromolecules. Since then, more than 85000 biological macromolecule structures have been determined and made available in the PDB archive. Through analysis of the corpus of data, it is possible to identify trends that can be used to inform us abou the future of structural biology and to plan the best ways to improve the management of the ever-growing amount of PDB data. [Copyright &y& Elsevier]

Graphene is a prospective candidate for various biomedical applications, including drug transporters, bioimaging agents, and scaffolds for tissue engineering, thanks to its superior electrical conductivity and biocompatibility. The clinical issue of nerve regeneration and rehabilitation still has a major influence on people's lives. Nanomaterials based on graphene have been exploited extensively to promote nerve cell differentiation and proliferation. Their high electrical conductivity and mechanical robustness make them appropriate for nerve tissue engineering. Combining graphene with other substances, such as biopolymers, may transmit biochemical signals that support brain cell division, proliferation, and regeneration. The utilization of nanocomposites based on graphene in neurogenesis and neuritogenesis is the primary emphasis of this review. Here are some examples of the many synthetic strategies used. For neuritogenesis and neurogenesis, it has also been explored to combine electrical stimulation with graphene-based materials.

Over the past few decades, zinc oxide nanoparticles have also proven to be essential to a variety of scientific research sectors, including antimicrobial therapy, tissue engineering, bioimaging, biosensors, drug delivery, gene delivery, and bioimaging. There is an urgent need to establish and develop unique alternative treatment modalities to treat neurodegenerative disorders due to the shortcomings of the existing drugs. As a possible therapy for brain diseases and disorders, the ability of the nanoparticles to cross the blood-brain barrier (BBB) as well as their reduced toxicity, solubility, and biodegradability has lately attracted attention. Scientists are quietly turning their attention to develop green synthesis of nanoparticles as an alternative to the physical and chemical techniques of producing the same. Existing literature has emphasized the use of ZnO for the potential treatment of cerebral ischemia and its neuroprotective properties. This work discusses the potential of ZnO prepared using Gynura cusimba extract and its nanocomposites with graphene quantum dots (GQDs) and its nitrogen doped variant, N-GQDs as neurotrophic agents, in accordance with our previous report on the use of GQDs and N-GQDs as neurotrophic agents. Pristine ZnO nanoparticles as well as composites were duly characterized by using several techniques to confirm the formation of the nanocomposites. Biological evaluation using the neurite outgrowth assay following the cell viability assay revealed that incorporation of GQDs and N-GQDs enhanced the neurite length in comparison to that of pristine ZnO with the nanocomposites of N-GQDs showing comparatively better results, corroborated by the real-time PCR studies as well.

Dual comb spectroscopy (DCS) is a broadband technique offering high resolution and fast data acquisition. Current state-of-the-art designs are based on a pair of fiber or solid-state lasers, which allow broadband spectroscopy but require a complicated stabilization setup. Semiconductor lasers are tunable, cost-effective, and easily integrable while limited by a narrow bandwidth. This motivates a hybrid design combining the advantages of both systems. However, establishing sufficiently long mutual coherence time remains challenging. This work describes a hybrid dual-comb spectrometer comprising a broadband fiber laser (FC) and an actively mode-locked semiconductor laser (MLL) with a narrow but tunable spectrum. A high mutual coherence time of around 100 seconds has been achieved by injection locking the MLL to a continuous laser (CW), which is locked on a single line of the FC. We have also devised a method to directly stabilize the entire spectrum of FC to a high finesse cavity. This results in a long term stability of 5 × 10 -12 at 1 second and 5 × 10 -14 at 350 seconds. Additionally, we have addressed the effect of cavity dispersion on the locking quality, which is important for broadband comb lasers.

Over time, developments in nano-biomedical research have led to the creation of a number of systems to cure serious illnesses. Tandem use of nano-theragnostics such as diagnostic and therapeutic approaches tailored to the individual disease treatment is crucial for further development in the field of biomedical advancements. Graphene has garnered attention in the recent times as a potential nanomaterial for tissue engineering and regenerative medicines owing to its biocompatibility among the several other unique properties it possesses. The zero-dimensional graphene quantum dots (GQDs) and their nitrogen-doped variant, nitrogen-doped GQDs (N-GQDs), have good biocompatibility, and optical and physicochemical properties. GQDs have been extensively researched owing to several factors such as their size, surface charge, and interactions with other molecules found in biological media. This work briefly elucidates the potential of electroactive GQDs as well as N-GQDs as neurotrophic agents. In vitro investigations employing the N2A cell line were used to evaluate the effectiveness of GQDs and N-GQDs as neurotrophic agents, wherein basic investigations such as SRB assay and neurite outgrowth assay were performed. The results inferred from immunohistochemistry followed by confocal imaging studies as well as quantitative real-time PCR (qPCR) studies corroborated those obtained from neurite outgrowth assay. We have also conducted a preliminary investigation of the pattern of gene expression for neurotrophic and gliotrophic growth factors using ex vivo neuronal and mixed glial cultures taken from the brains of postnatal day 2 mice pups. Overall, the studies indicated that GQDs and N-GQDs hold prospect as a framework for further development of neuroactive compounds for relevant central nervous system (CNS) purposes.

Significant contributions have been made towards the development of flexible energy storage devices to meet the ever-growing energy demand. Flexibility, mechanical stability, and electrical conductivity are three critical qualities that distinguish conducting polymers from other materials. Polyaniline (PANI) has drawn considerable attention among the various conducting polymers for use in flexible supercapacitors. PANI offers several desirable properties including high porosity, a large surface area, and high conductivity. Despite its merits, it also suffers from poor cyclic stability, low mechanical strength, and notable discrepancy between theoretical and actual capacitance. These shortcomings have been addressed by creating composites of PANI with structurally sturdy elements such as graphene, carbon nanotubes (CNTs), metal-organic framework (MOFs), MXenes, etc. , thus enhancing the performance of supercapacitors. This review outlines the several schemes adopted to prepare diverse binary and ternary composites of PANI as the electrode material for flexible supercapacitors and the significant impact of composite formation on the flexibility and electrochemical performance of the fabricated pliable supercapacitors.

Communication and collaboration are key science competencies that support sharing of scientific knowledge with experts and non-experts alike. On the one hand, they facilitate interdisciplinary conversations between students, educators, and researchers, while on the other they improve public awareness, enable informed choices, and impact policy decisions. Herein, we describe an interdisciplinary undergraduate course focused on using data from various bioinformatics data resources to explore the molecular underpinnings of diabetes mellitus (Types 1 and 2) and introducing students to science communication. Building on course materials and original student-generated artifacts, a series of collaborative activities engaged students, educators, researchers, healthcare professionals and community members in exploring, learning about, and discussing the molecular bases of diabetes. These collaborations generated novel educational materials and approaches to learning and presenting complex ideas about major global health challenges in formats accessible to diverse audiences., (© 2022 The Authors. Biochemistry and Molecular Biology Education published by Wiley Periodicals LLC on behalf of International Union of Biochemistry and Molecular Biology.)

Now in its 52nd year of continuous operations, the Protein Data Bank (PDB) is the premiere open-access global archive housing three-dimensional (3D) biomolecular structure data. It is jointly managed by the Worldwide Protein Data Bank (wwPDB) partnership. The Research Collaboratory for Structural Bioinformatics Protein Data Bank (RCSB PDB) is funded by the National Science Foundation, National Institutes of Health, and US Department of Energy and serves as the US data center for the wwPDB. RCSB PDB is also responsible for the security of PDB data in its role as wwPDB-designated Archive Keeper. Every year, RCSB PDB serves tens of thousands of depositors of 3D macromolecular structure data (coming from macromolecular crystallography, nuclear magnetic resonance spectroscopy, electron microscopy, and micro-electron diffraction). The RCSB PDB research-focused web portal (RCSB.org) makes PDB data available at no charge and without usage restrictions to many millions of PDB data consumers around the world. The RCSB PDB training, outreach, and education web portal (PDB101.RCSB.org) serves nearly 700 K educators, students, and members of the public worldwide. This invited Tools Issue contribution describes how RCSB PDB (i) is organized; (ii) works with wwPDB partners to process new depositions; (iii) serves as the wwPDB-designated Archive Keeper; (iv) enables exploration and 3D visualization of PDB data via RCSB.org; and (v) supports training, outreach, and education via PDB101.RCSB.org. New tools and features at RCSB.org are presented using examples drawn from high-resolution structural studies of proteins relevant to treatment of human cancers by targeting immune checkpoints., (© 2022 The Protein Society.)

The Research Collaboratory for Structural Bioinformatics Protein Data Bank (RCSB PDB), funded by the US National Science Foundation, National Institutes of Health, and Department of Energy, has served structural biologists and Protein Data Bank (PDB) data consumers worldwide since 1999. RCSB PDB, a founding member of the Worldwide Protein Data Bank (wwPDB) partnership, is the US data center for the global PDB archive housing biomolecular structure data. RCSB PDB is also responsible for the security of PDB data, as the wwPDB-designated Archive Keeper. Annually, RCSB PDB serves tens of thousands of three-dimensional (3D) macromolecular structure data depositors (using macromolecular crystallography, nuclear magnetic resonance spectroscopy, electron microscopy, and micro-electron diffraction) from all inhabited continents. RCSB PDB makes PDB data available from its research-focused RCSB.org web portal at no charge and without usage restrictions to millions of PDB data consumers working in every nation and territory worldwide. In addition, RCSB PDB operates an outreach and education PDB101.RCSB.org web portal that was used by more than 800,000 educators, students, and members of the public during calendar year 2020. This invited Tools Issue contribution describes (i) how the archive is growing and evolving as new experimental methods generate ever larger and more complex biomolecular structures; (ii) the importance of data standards and data remediation in effective management of the archive and facile integration with more than 50 external data resources; and (iii) new tools and features for 3D structure analysis and visualization made available during the past year via the RCSB.org web portal., (© 2021 The Protein Society.)

Entangled photon pairs are a fundamental component for testing the foundations of quantum mechanics, and for modern quantum technologies such as teleportation and secured communication. Current state-of-the-art sources are based on nonlinear processes that are limited in their efficiency and wavelength tunability. This motivates the exploration of physical mechanisms for entangled photon generation, with a special interest in mechanisms that can be heralded, preferably at telecommunications wavelengths. Here we present a mechanism for the generation of heralded entangled photons from Rydberg atom cavity quantum electrodynamics (cavity QED). We propose a scheme to demonstrate the mechanism and quantify its expected performance. The heralding of the process enables non-destructive detection of the photon pairs. The entangled photons are produced by exciting a rubidium atom to a Rydberg state, from where the atom decays via two-photon emission (TPE). A Rydberg blockade helps to excite a single Rydberg excitation while the input light field is more efficiently collectively absorbed by all the atoms. The TPE rate is significantly enhanced by a designed photonic cavity, whose many resonances also translate into high-dimensional entanglement. The resulting high-dimensionally entangled photons are entangled in more than one degree of freedom: in all of their spectral components, in addition to the polarization-forming a hyper-entangled state, which is particularly interesting in high information capacity quantum communication. We characterize the photon comb states by analyzing the Hong-Ou-Mandel interference and propose proof-of-concept experiments.

The Research Collaboratory for Structural Bioinformatics Protein Data Bank (RCSB PDB, rcsb.org), the US data center for the global PDB archive, serves thousands of Data Depositors in the Americas and Oceania and makes 3D macromolecular structure data available at no charge and without usage restrictions to more than 1 million rcsb.org Users worldwide and 600 000 pdb101.rcsb.org education-focused Users around the globe. PDB Data Depositors include structural biologists using macromolecular crystallography, nuclear magnetic resonance spectroscopy and 3D electron microscopy. PDB Data Consumers include researchers, educators and students studying Fundamental Biology, Biomedicine, Biotechnology and Energy. Recent reorganization of RCSB PDB activities into four integrated, interdependent services is described in detail, together with tools and resources added over the past 2 years to RCSB PDB web portals in support of a 'Structural View of Biology.'