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The preferential concentration of sedimenting particles in decaying homogeneous isotropic turbulence is investigated using radial distribution functions (RDF). Direct numerical simulations of polydisperse distributions of non-sedimenting and sedimenting particles of radii 10–55 μm are performed. We see a power law behaviour for the RDF in decaying turbulence and the power-law relation derived by Chun et al. (J Fluid Mech 536:219–251, 2005) for the RDF of non-sedimenting particles holds for sedimenting particles as well. Empirical formulas are generated for the power-law coefficients which are shown to be functions of the Stokes number and the Taylor Reynolds number for sedimenting particles. An in-depth analysis of the turbulent kinematic collision kernel for both non-sedimenting and sedimenting collision kernels confirms that gravity enhances the collision kernel for unequal sized particles and decreases for same-sized particles. Models are created for both monodisperse and bidisperse RDFs which are combined with existing models for the conditional radial relative velocities of colliding particles to predict kinematic collision kernels for both non-sedimenting and sedimenting particles. The effect on the collision kernel due to turbulence is also explored and enhancement of factors of up to three is observed with respect to the gravitational collision kernel.

Plasmonic-based reticular materials are promising photocatalysts for CO2 reduction due to their efficient charge separation, band structure and crystalline properties.

Singer et al. (2022) argue that the current lexical shift within autism research towards more neutral terminology hinders accurate scientific description of the wide range of autistic experiences, particularly within clinical and medical contexts. In this Letter to the Editor, we present an examination and criticism of these claims. This letter is authored and co-signed by a diverse group of autistic researchers, scholars, clinicians, and self-advocates with a wide range of clinical presentation and support needs, as well as non-autistic researchers, scholars, clinicians, and loved ones of autistic people.

There is an urgent need for anti-viral agents that treat SARS-CoV-2 infection. The shortest path to clinical use is repurposing of drugs that have an established safety profile in humans. Here, we first screened a library of 1,900 clinically safe drugs for inhibiting replication of OC43, a human beta-coronavirus that causes the common-cold and is a relative of SARS-CoV-2, and identified 108 effective drugs. We further evaluated the top 26 hits and determined their ability to inhibit SARS-CoV-2, as well as other pathogenic RNA viruses. 20 of the 26 drugs significantly inhibited SARS-CoV-2 replication in human lung cells (A549 epithelial cell line), with EC50 values ranging from 0.1 to 8 micromolar. We investigated the mechanism of action for these and found that masitinib, a drug originally developed as a tyrosine-kinase inhibitor for cancer treatment, strongly inhibited the activity of the SARS-CoV-2 main protease 3CLpro. X-ray crystallography revealed that masitinib directly binds to the active site of 3CLpro, thereby blocking its enzymatic activity. Mastinib also inhibited the related viral protease of picornaviruses and blocked picornaviruses replication. Thus, our results show that masitinib has broad anti-viral activity against two distinct beta-coronaviruses and multiple picornaviruses that cause human disease and is a strong candidate for clinical trials to treat SARS-CoV-2 infection.

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Giant Manta Ray is assessed as Vulnerable by IUCN and has a very low reproductive capacity. India is also one of the major manta fishing countries; however, commerce in gill plates is not well documented. With information of these gentle giants scanty in literature, record of morphological and morphometric data pertaining to Mobula foetus from this region is very important. The disc length (DL) of the foetus recorded in Kochi was only 30 mm and the foetus already had pigmentation patterns in the ventral portion of the cephalic horn and displayed the presence of an umbilical attachment. The presence of the gravid female is not a solitary event and there are many such cases which may have gone unnoticed. Together with our recent findings, and previous records, this data reinforces the importance of the west coast as potential reproduction grounds for M. birostris. This information is crucial for the establishment and progression of conservation measures for this migratory species.

The release of large volumes of anthropogenic CO2 coupled with growing exploitation of fossil fuels has led to very serious issues such as global warming and energy crisis in the world. One of the most promising solutions for addressing these challenges is photocatalytic reduction of CO2 into useful chemical feedstocks. The adsorption/activation and reduction of CO2 on the surface of heterogeneous catalysts, in addition to visible light harvesting and efficient charge separation, remains a scientifically challenging problem, which is severely limiting the total photoconversion and selectivity of CO2 reduction on photocatalysts. Reticular materials such as metal organic frameworks (MOFs) and covalent organic frameworks (COFs) are a class of porous materials, which have lately been investigated as photocatalysts due to their excellent tuneable structural and photochemical properties. Single-atom catalysts offer great potential to enable chemical transformation of CO2 when anchored to an appropriate support material. Naturally abundant porphyrin has been effective for a variety of processes including light-harvesting, oxygen transport and catalytic processes. The rigidity, robustness, and multifunctionality of reticular materials enable them to be used in a spectrum of applications. Modular optimization, rational design and integration of single-atoms and porphyrin onto metal- and covalent-organic frameworks pave a new pathway toward the photoreduction of CO2. In the context of recent advancements in the field of reticular materials, porphyrin and single atom based MOFs and COFs towards photocatalytic CO2 reduction are summarised in this review. This review also includes discussion on the current breakthroughs in fundamental knowledge, reaction mechanisms, and pathways of CO2 photoreduction, as well as gives an overview of the approaches towards improving the CO2 reduction efficiency and selectivity of these reticular photocatalytic materials. Also, the challenges and perspectives of CO2 photoreduction over these heterogeneous catalysts have also been presented in this report.

A novel ‘turn on’ fluorescence aptasensor based on an energy transfer mechanism has been designed using ssDNA conjugated carbon dots (C-dots) and graphene oxide (GO). ssDNA-C-dots on interaction with ssDNA modified GO, allow fluorescence quenching due to energy transfer from the C-dots to GO by DNA duplex bridge formation between them. The property of MNase to cleave DNA is exploited to inhibit the interaction between C-dots and GO. As the bridge breaks, it inhibits interaction and regeneration of fluorescence occurs. Increase in PL intensity is proportional to the concentration of MNase present, thus facilitating the detection of MNase of S. aureus. Different lengths of ssDNA are used to study the mechanism of energy transfer. The C-dots synthesized through a green hydrothermal method using maize biomass are evaluated for cytotoxicity and the measured IC50 value indicates their non-toxicity. The C-dots exhibited 23% fluorescence quantum yield and the sensing mechanism of energy transfer is substantiated by UV visible, PL and time resolved photoluminescence (TRPL) studies. Real time samples were analyzed to validate the probe designed.

This paper describes the interface and testing of an indoor navigation app - ASSIST - that guides blind & visually impaired (BVI) individuals through an indoor environment with high accuracy while augmenting their understanding of the surrounding environment. ASSIST features personalized interfaces by considering the unique experiences that BVI individuals have in indoor wayfinding and offers multiple levels of multimodal feedback. After an overview of the technical approach and implementation of the first prototype of the ASSIST system, the results of two pilot studies performed with BVI individuals are presented – a performance study to collect data on mobility (walking speed, collisions, and navigation errors) while using the app, and a usability study to collect user evaluation data on the perceived helpfulness, safety, ease-of-use, and overall experience while using the app. Our studies show that ASSIST is useful in providing users with navigational guidance, improving their efficiency and (more significantly) their safety and accuracy in wayfinding indoors. Findings and user feed-back from the studies confirm some of the previous results, while also providing some new insights into the creation of such an app, including the use of customized user interfaces and expanding the types of information provided.

Nowadays, charge separation and efficient solar-light absorption are the main challenges in the photoreduction of CO2. Although significant efforts have been made to overcome these issues, including the use of cocatalysts and doping, photocatalysts still suffer from low photocatalytic activity and stability. Herein, the localized surface plasmonic resonance (LSPR) effect of Au nanoparticles deposited into the zeolitic imidazolate framework (ZIF-67) was investigated for the photoreduction of CO2. Different Au loadings in ZIF were prepared and their effects were studied on photocatalytic performance. Plasmonic Au nanoparticles (PNPs) in the size range of 30–40 nm improved visible-light absorption, enhanced charge separation, and played an important role in selectivity. A volcano relationship of plasmonic Au NPs with methanol and ethanol generation was found, along with the deposition of plasmonic Au nanoparticles. A total yield of 2.5 mmol g–1 h–1 of methanol and 0.5 mmol g–1 h–1 of ethanol were obtained, which are the highest values compared to those reported in other studies. Finally, our results revealed that Au PNPs have a significant impact on the selectivity and photocatalytic activity of ZIF-67 for the photoreduction of CO2 and could be a promising alternative toward designing plasmonic reticular materials.

International audience; Because of their innocuity, Au nanowires present an interesting field of applications in biology and, particularly, in cancer therapy. Since their morphology and distribution can greatly affect their performances, being able to control their mode of growth is important. Various elaboration techniques including “top-down” and “bottom-up” approaches have been developed. In this work, we propose an efficient maskless method to grow Au nanowires with the help of hydrogen plasma treatment of Au thin films. We have been able to grow Au nanowires by taking advantage of spinodal dewetting of an Au thin film and the supply of silicon radicals resulting from hydrogen plasma etching of amorphous silicon coating the walls of the reactor. A variety of techniques have been applied to study the microstructure and the optical properties of Au nanowires. A strong photothermal effect of Au nanowires has been demonstrated with the help of visible laser light. In order to study the nanowire growth, the transport of Au atoms is discussed, and a growth mechanism is proposed.

The dynamics of a subsiding shell at the edges of actively growing shallow cumulus clouds with updrafts is analyzed using direct numerical simulation. The actively growing clouds have a fixed in-cloud buoyancy and velocity. Turbulent mixing and evaporative cooling at the cloud edges generate a subsiding shell that grows with time. A self-similar regime is observed for first- and second-order moments when normalized with respective maximum values. Internal scales derived from integral properties of the flow problem are identified. A self-similarity analysis using these scales reveals that contrary to classical self-similar flows, the turbulent kinetic energy budget terms and velocity moments scale according to the buoyancy and not with the mean velocity. The shell thickness is observed to increase linearly with time. The buoyancy scale remains time invariant and is set by the initial cloud–environment thermodynamics. The shell accelerates ballistically with a magnitude set by the saturation value of the buoyancy of the cloud–environment mixture. In this regime, the shell is buoyancy driven and independent of the in-cloud velocity. Relations are obtained for predicting the shell thickness and minimum velocities by linking the internal scales with external flow parameters. The values thus calculated are consistent with the thickness and velocities observed in typical shallow cumulus clouds. The entrainment coefficient is a function of the initial state of the cloud and the environment, and is shown to be on the same order of magnitude as fractional entrainment rates calculated for large-scale models.

Thyroid disorder is the second most frequently encountered endocrinological condition after diabetes mellitus. When vitamin B12 deficiency coexists with hypothyroidism, neurological symptoms and signs are more pronounced. Studies have shown holotranscobalamin (Active B12) may be a more sensitive marker in the early diagnosis of Vitamin B12 deficiency than total B12. The study aimed to evaluate the serum levels of active B12 in patients with clinical hypothyroidism and to correlate active B12 and thyroid profiles. The case-control study was carried out in a tertiary hospital on 80 study subjects, comprising of 40 confirmed hypothyroidism patients and 40 age- and gender-matched healthy controls. Serum thyroid profile and active B12 assays were performed by Chemiluminescent Microparticle Immunoassay. Statistical methods such as independent t-test and Pearson’s correlation were used to compare and correlate quantitative data. A significant percentage (90%) of hypothyroid patients had vitamin B12 deficiency, with a mean value of 17.39 ± 5.73 pmol/L. Active B12 showed a positive correlation with T3 (r = 0.818, P < 0.001) and T4 (r = 0.851, P < 0.001) and a negative correlation with TSH (r = -0.930, P < 0.001). Vitamin B12 deficiency was found in patients with hypothyroidism. This vitamin B12 deficiency may be caused by inadequate malabsorption, as seen in hypothyroidism. HoloTC (Active B12) may be a promising marker for early detection and management of B12 deficiency, which may be beneficial in preventing irreversible neurological damage at an early stage.

ATAC-seq is a fast and sensitive method for the epigenomic profiling of open chromatin and for mapping of transcription factor binding sites [1]. Despite the development of the Omni-ATAC protocol for the profiling of chromatin accessibility in frozen tissues [2], studies in adipose tissue have been restricted due to technical challenges including the high lipid content of adipocytes and reproducibility issues between replicates. Here, we provide a modified Omni-ATAC protocol that achieves high data reproducibility in various tissue types from rat, including adipose and muscle tissues [3].•This protocol describes a methodology that enables chromatin accessibility profiling from snap-frozen rat adipose and muscle tissues.•The technique comprises an optimized bead-based tissue homogenization process that substitutes to Dounce homogenization, reduces variability in the experimental procedure, and is adaptable to various tissue types.•In comparison with the Omni-ATAC protocol, the method described here results in improved ATAC-seq data quality that complies with ENCODE quality standards.

Video games remain largely inaccessible to visually impaired people (VIPs). Today's blind-accessible games are highly simplified renditions of what sighted players enjoy, and they do not give VIPs the same freedom to look around and explore game worlds on their own terms. In this work, we introduce NavStick, an audio-based tool for looking around within virtual environments, with the aim of making 3D adventure video games more blind-accessible. NavStick repurposes a game controller's thumbstick to allow VIPs to survey what is around them via line-of-sight. In a user study, we compare NavStick with traditional menu-based surveying for different navigation tasks and find that VIPs were able to form more accurate mental maps of their environment with NavStick than with menu-based surveying. In an additional exploratory study, we investigate NavStick in the context of a representative 3D adventure game. Our findings reveal several implications for blind-accessible games, and we close by discussing these., Comment: 14 pages with 13 figures and 2 tables

Video games created for visually impaired players (VIPs) remain inequivalent to those created for sighted players. Sighted players use minimaps within games to learn how their surrounding environment is laid out, but there is no effective analogue to the minimap for visually impaired players. A major accessibility challenge is to create a generalized, acoustic (non-visual) version of the minimap for VIPs. To address this challenge, we develop and investigate four acoustic minimap techniques which represent a breadth of ideas for how an acoustic minimap might work: a companion smartphone app, echolocation, a directional scanner, and a simple menu. Each technique is designed to communicate information about the area around the player within a game world, providing functionality analogous to a visual minimap but in acoustic form. We close by describing a user study that we are performing with these techniques to investigate the factors that are important in the design of acoustic minimap tools.

Recurrent jellyfish blooms and their impacts on ecosystem deliverables of coastal habitats have become a major ecological concern. In view of this, repercussions of a surge in the jellyfish population on the plankton community were studied in Cochin estuary (CE), the largest tropical estuary along the southwest coast of India. Evaluation of hydrographic attributes and plankton community of the CE during early and late pre-monsoon revealed a marked disparity in its hydrography which favoured an increase in jellyfish abundances during late pre-monsoon, eliciting distinct impacts on the plankton community. The escalation in the jellyfish abundance and their subsequent predation on the crustacean plankton released the phytoplankton community from the grazing pressure resulting in a trophic cascade in the planktonic food web. The indiscriminate feeding of jellyfishes on the ichthyoplankton, decapod larvae, and Copepoda, the primary diet component of forage fishes evoked a potent threat to the fishery potential of CE.

Interfaces at the edge of an idealised, non-precipitating, warm cloud are studied using Direct Numerical Simulation (DNS) complemented with a Lagrangian particle tracking routine. Once a shell has formed, four zones can be distinguished: the cloud core, visible shell, invisible shell and the environment. The union of the visible and invisible regions is the shell commonly referred to in literature. The boundary between the invisible shell and the environment is the Turbulent-NonTurbulent Interface (TNTI) which is typically not considered in cloud studies. Three million particles were seeded homogeneously across the domain and properties were recorded along individual trajectories. The results demonstrate that the traditional cloud boundary (separating cloudy and non-cloudy regions using thresholds applied on liquid condensate or updraft velocity) are some distance away from the TNTI. Furthermore, there is no dynamic difference between the traditional liquid-condensate boundary and the region extending to the TNTI. However, particles crossing the TNTI exhibit a sharp jump in enstrophy and a smooth increase in buoyancy. The traditional cloud boundary coincides with the location of minimum buoyancy in the shell. The shell pre-mixes the entraining and detraining air and analysis reveals a highly skewed picture of entrainment and detrainment at the traditional cloud boundary. A preferential entrainment of particles with velocity and specific humidity higher than the mean values in the shell is observed. Large-eddy simulation of a more realistic setup detects an interface with similar properties using the same thresholds as in the DNS, indicating that the DNS results extrapolate beyond their idealised conditions.

Chromatin accessibility is a key factor influencing gene expression. We optimized the Omni-ATAC-seq protocol and used it together with RNA-seq to investigate cis-regulatory elements in rat white adipose and skeletal muscle, two tissues with contrasting metabolic functions. While promoter accessibility correlated with RNA expression, integration of the two datasets identified tissue-specific differentially accessible regions (DARs) that predominantly localized in intergenic and intron regions. DARs were mapped to differentially expressed (DE) genes enriched in distinct biological processes in each tissue. Randomly selected DE genes were validated by qPCR. Top enriched motifs in DARs predicted binding sites for transcription factors (TFs) showing tissue-specific up-regulation. The correlation between differential chromatin accessibility at a given TF binding motif and differential expression of target genes further supported the functional relevance of that motif. Our study identified cis-regulatory regions that likely play a major role in the regulation of tissue-specific gene expression in adipose and muscle.

A cell uses its cytoskeletal machinery to control its membrane projections to seek and obtain cargo from its microenvironment. Though this process has been studied extensively using spherical cargo, it remains largely unknown how the process operates with vectorial ones, which are non-spheroid rigid objects with an aspect ratio. In this study, a vectorial cargo, silicon nanowire, was observed to have multiple modes of initial contact and to realign along a membrane projection or on a lamella. Using a qualitative theoretical approach, we demonstrate how membrane energy fluctuations potentially drive this realignment of a vectorial cargo. This was understood by calculations which establish how aspect ratio controls the energy landscape in a vectorial object and its influence on relative energy stability of nanowire-membrane contacts. A study of the realignment transport of vectorial cargoes and their comparison with Ornstein-Uhlenbeck process simulations revealed how one-dimensional time-correlated noise manifested in the transport process. Furthermore, a comparison between sliding of nanowires on cell membrane contacts versus rotational realignment with the same model revealed identical characteristics behind both. The understanding that one-dimensional time-correlated noise underlies both sliding and rotation of a vectorial cargo establishes how cytoskeletal dynamics effectively couples their realignment with subsequent transport for phagocytosis. This work establishes the significance of vectorial cargoes and the nature of underlying vectorial processes that enable their cellular processing.

There is an urgent need for anti-viral agents that treat SARS-CoV-2 infection. The shortest path to clinical use is repurposing of drugs that have an established safety profile in humans. Here, we first screened a library of 1,900 clinically safe drugs for inhibiting replication of OC43, a human beta-coronavirus that causes the common-cold and is a relative of SARS-CoV-2, and identified 108 effective drugs. We further evaluated the top 26 hits and determined their ability to inhibit SARS-CoV-2, as well as other pathogenic RNA viruses. 20 of the 26 drugs significantly inhibited SARS-CoV-2 replication in human lung cells (A549 epithelial cell line), with EC50 values ranging from 0.1 to 8 micromolar. We investigated the mechanism of action for these and found that masitinib, a drug originally developed as a tyrosine-kinase inhibitor for cancer treatment, strongly inhibited the activity of the SARS-CoV-2 main protease 3CLpro. X-ray crystallography revealed that masitinib directly binds to the active site of 3CLpro, thereby blocking its enzymatic activity. Mastinib also inhibited the related viral protease of picornaviruses and blocked picornaviruses replication. Thus, our results show that masitinib has broad anti-viral activity against two distinct beta-coronaviruses and multiple picornaviruses that cause human disease and is a strong candidate for clinical trials to treat SARS-CoV-2 infection.

Laser-assisted synthesis yields silicon carbide–elastomer composite for bioelectric modulation of cells and tissues., Conducting or semiconducting materials embedded in insulating polymeric substrates can be useful in biointerface applications; however, attainment of this composite configuration by direct chemical processes is challenging. Laser-assisted synthesis has evolved as a fast and inexpensive technique to prepare various materials, but its utility in the construction of biophysical tools or biomedical devices is less explored. Here, we use laser writing to convert portions of polydimethylsiloxane (PDMS) into nitrogen-doped cubic silicon carbide (3C-SiC). The dense 3C-SiC surface layer is connected to the PDMS matrix via a spongy graphite layer, facilitating electrochemical and photoelectrochemical activity. We demonstrate the fabrication of arbitrary two-dimensional (2D) SiC-based patterns in PDMS and freestanding 3D constructs. To establish the functionality of the laser-produced composite, we apply it as flexible electrodes for pacing isolated hearts and as photoelectrodes for local peroxide delivery to smooth muscle sheets.

With the ever-rising pollution of water bodies caused by human-made actions as well as natural calamities, water monitoring systems are the focal point for society. Water-related application has much potential for automation. With the advent of big data analytics, there is a multitude of verticals in water quality, smart irrigation, and smart water distribution network. All these work well with accurate and real-time data. The requirements for multiple sensor parameters and robust communication framework that can be extended to various domains of water monitoring applications are the most critical hindrance for the development of an automation application in this domain. This work proposes a system that overcomes these problems. With the use of an industrial multi-parameter sensor node, EXO Sonde the desired sensor values can be extracted from the physical world. The sensed data is processed and communicated forward to the server forward through a layered architecture to a server. The sensor node utilizes a file system to save the sensor data in case of network loss. The communication technology between nodes and sensors is GSM. In the server, the data gets stored and gets visualized in a web UI.