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Excavation at the site of Bhagatrav yielded four layers of cultural deposits: the lowermost being the Sorath Harappan, the upper two are medieval, and layer three caps the Sorath Harappan layer. A horn-deity painted dish was found in a stratified context at the lowest level. The medieval deposit includes turquoise glazed and celadon wares, followed by an abundance of Monochrome Glazed Ware, which is otherwise known as Khambhat ware. The date of the Sorath Harappan layer of the site, the time and space of the horn-deity motif in the Harappan world, and the date of Khambhat ware have long been subjects of discussion. With the help of a series of absolute dating (radiocarbon and luminescence), this paper attempts to place the site, horn-deity motif, and the Khambhat ware in the cultural chronology of Gujarat.
Mental health apps (MHAs) are increasingly popular in India due to rising mental health awareness and app accessibility. Despite their benefits, like mood tracking, sleep tools and virtual therapy, MHAs lack regulatory oversight. India's framework, including the Central Drugs Standard Control Organization (CDSCO) and Medical Device Rules 2017, does not cover standalone health apps, raising concerns about data privacy and accuracy. Establishing a centralised regulatory body with guidelines for MHAs is essential for user safety and efficacy. This paper examines the current regulatory landscape, compares international approaches and proposes a tiered regulatory framework to foster responsible innovation while safeguarding user interests in digital mental health services.
Bilateral teleoperation systems encounter challenges in achieving synchronisation between master and slave robots due to communication time delays. This paper addresses the instability caused by these delays and proposes a solution through advanced control algorithms. Nonlinear optimisation algorithms might only sometimes deliver solutions in the allotted time, particularly when handling complicated, high-dimensional issues or when optimisation iterations are extensive. The study first develops a comprehensive mathematical model encompassing the dynamics and communication intricacies of both master and slave sides in teleoperation. By recognising the limitations of existing proportional-derivative controllers in compensating for communication errors, a sequential quadratic programming-proportional-integral-derivative (SQP-PID) controller is introduced. This controller accumulates and rectifies synchronisation delay errors, ensuring precise control without steady-state deviations. The proposed SQP-PID controller stands out for its ability to handle steady-state errors effectively, offering swift response and maintaining stability. Leveraging the SQP optimisation algorithm, it intelligently tunes the parameters, minimising synchronisation errors. The approach capitalises on the simplicity, performance, and robustness of the SQP-PID controller, providing a promising avenue for enhancing bilateral teleoperation systems’ accuracy and stability, maintaining initial discrepancy with a best fitness value of 0.98 % in varied operating conditions.
We describe a simple, cost-effective, green method for producing capped silver nanoparticles (Ag NPs) using a handheld portable mesh nebulizer. The precursor solution containing a 1:1 mixture of silver nitrate (AgNO3) and ligand (glycerol or sodium alginate) was sprayed using the nebulizer. The Ag NPs were generated in the water microdroplets within a few milliseconds under ambient conditions without any external reducing agent or action of a radiation source. The synthesized nanoparticles were characterized by using high-resolution transmission electron microscopy (HR-TEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction analysis (XRD), which validated the formation of Ag NPs. The synthesized glycerate-capped silver nanoparticles (Ag-gly NPs) were used as a catalyst to show the oxidative coupling of aniline to form azobenzene products with a yield of up to 61%. Experiments conducted using Ag NPs produced in the droplets demonstrated more than 99% antibacterial activity when contacting Escherichia Coli. Our in-situ synthesis-cum-fabrication technique using a portable sprayer represents a viable alternative to the existing fiber or hydrogel-based antimicrobial wound healing.
Modern day building design projects require multidisciplinary expertise from architects and engineers across various phases of the design (conceptual, preliminary, and detailed) and construction processes. The Architecture Engineering and Construction (AEC) community has recently shifted gears toward leveraging design optimization techniques to make well-informed decisions in the design of buildings. However, most of the building design optimization efforts are either multidisciplinary optimization confined to just a specific design phase (conceptual/preliminary/detailed) or single disciplinary optimization (structural/thermal/daylighting/energy) spanning across multiple phases. Complexity in changing the optimization setup as the design progresses through subsequent phases, interoperability issues between modeling and physics-based analysis tools used at later stages, and the lack of an appropriate level of design detail to get meaningful results from these sophisticated analysis tools are few challenges that limit multi-phase multidisciplinary design optimization (MDO) in the AEC field. This paper proposes a computational building design platform leveraging concurrent engineering techniques such as interactive problem structuring, simulation-based optimization using meta models for energy and daylighting (machine learning based) and tradespace visualization. The proposed multi-phase concurrent MDO framework is demonstrated by using it to design and optimize a sample office building for energy and daylighting objectives across multiple phases. Furthermore, limitations of the proposed framework and future avenues of research are listed.
Sediment transfer from the interiors of the Himalaya is complex because the archives are influenced by both glacial and monsoonal cycles. To deconvolve the coupling of glacial and monsoonal effects on sediment transfer processes, we investigate the Late Pleistocene–Holocene sediment archive in the Upper Chenab valley. Optically stimulated luminescence (OSL) ages from the archive indicate major aggradation during ca. 20–10 ka. Isotopic fingerprinting using Sr-Nd isotopes in silt fractions together with clast counts in boulder-pebble fractions indicate a decreasing Higher Himalayan sediment flux in the archive with time. Decreasing clast size, increasing clast roundness, increasing matrix to clast ratio, and dominance of the Higher Himalayan sourcing unequivocally suggest strong glacial influence during the initial stages of the archive formation. This evidence also agrees with the existing retreat ages of glaciers in the Upper Chenab valley. Results of our study also show that the upper parts of the archive contain significant fluvial sediment contribution from the Lesser Himalaya, which suggests an active role of the stronger Indian Summer Monsoon (ISM) in the region during the Early Holocene. The apparent decrease in sediment supply from the Higher Himalayan sources could have been due to longer source-to-sink transport in the Early Holocene and/or increased hillslope flux from Lesser Himalayan sources.
Recent disruption of medical oxygen during the second wave of coronavirus disease 2019 (COVID-19) has caused nationwide panic. This study attempts to objectively analyze the medical oxygen supply chain in India along the principles of value stream mapping (VSM), identify bottlenecks, and recommend systemic improvements.
Methods:
Process mapping of the medical oxygen supply chain in India was done. Different licenses and approvals, their conditions, compliances, renewals, among others were factored in. All relevant circulars (Government Notices), official orders, amendments, and gazette notifications pertaining to medical oxygen from April 2020 to April 2021 were studied and corroborated with information from Petroleum and Explosives Safety Organization (PESO) official website.
Results:
Steps of medical oxygen supply chain right from oxygen manufacture to filling, storage, and transport up to the end users; have regulatory bottlenecks. Consequently, flow of materials is sluggish and very poor information flow has aggravated the inherent inefficiencies of the system. Government of India has been loosening regulatory norms at every stage to alleviate the crisis.
Conclusions:
Regulatory bottlenecks have indirectly fueled the informal sector over the years, which is not under Government’s control with difficulty in controlling black-marketing and hoarding. Technology enabled, data-driven regulatory processes with minimum discretionary human interface can make the system more resilient.
The process of radiation pressure acceleration (RPA) of ions is investigated with the aim of suppressing the Rayleigh–Taylor-like transverse instabilities in laser–foil interaction. This is achieved by imposing surface and density modulations on the target surface. We also study the efficacy of RPA of ions from density modulated and structured targets in the radiation dominated regime where the radiation reaction effects are important. We show that the use of density modulated and structured targets and the radiation reaction effects can help in achieving the twin goals of high ion energy (in GeV range) and lower energy spread.
Population-based surveys commonly use point-of-care (POC) methods with capillary blood samples for estimating Hb concentrations; these estimates need to be validated by comparison with reference methods using venous blood. In a cross-sectional study in 748 participants (17–86 years, 708 women, Hb: 5·1 to 18·2 g/dl) from Hyderabad, India, we validated Hb measured from a pooled capillary blood sample by a POC autoanalyser (Horiba ABX Micros 60OT, Hb-C-AA) by comparison with venous blood Hb measured by two reference methods: POC autoanalyser (Hb-V-AA) and cyanmethemoglobin method (Hb-V-CM). These comparisons also allowed estimation of blood sample-related and equipment-related differences in the Hb estimates. We also conducted a longitudinal study in 426 participants (17–21 years) to measure differences in the Hb response to iron folate (IFA) treatment by the capillary blood POC method compared with the reference methods. In the cross-sectional study, Bland–Altman analyses showed trivial differences between source of blood (Hb-C-AA and Hb-V-AA; mean difference, limits of agreement: 0·1, −0·8 to 1·0 g/dl) and between analytical methods (Hb-V-AA and Hb-V-CM; mean difference, limits of agreement: < 0·1, −1·8 to 1·8 g/dl). Cross-sectional anaemia prevalence estimated using Hb-C-AA did not differ significantly from Hb-V-CM or Hb-V-AA. In the longitudinal study, the Hb increment in response to IFA intervention was not different when using Hb-C-AA (1·6 ± 1·7 g/dl) compared with Hb-V-AA (1·7 ± 1·7 g/dl) and Hb-V-CM (1·7 ± 1·7 g/dl). The pooled capillary blood–autoanalyzer method (Hb-C-AA) offers a practical and accurate way forward for POC screening of anaemia.
The Himalayan glaciers contribute significantly to regional water resources. However, limited field observations restrict our understanding of glacier dynamics and behaviour. Here, we investigated the long-term in situ mass balance, meteorology, ice velocity and discharge of the Chhota Shigri Glacier. The mean annual glacier-wide mass balance was negative, −0.46 ± 0.40 m w.e. a−1 for the period 2002–2019 corresponding to a cumulative wastage of −7.87 m w.e. Winter mass balance was 1.15 m w.e. a−1 and summer mass balance was −1.35 m w.e. a−1 over 2009–2019. Surface ice velocity has decreased on average by 25–42% in the lower and middle ablation zone (below 4700 m a.s.l.) since 2003; however, no substantial change was observed at higher altitudes. The decrease in velocity suggests that the glacier is adjusting its flow in response to negative mass balance. The summer discharge begins to rise from May and peaks in July, with a contribution of 43%, followed by 38% and 19% in August and September, respectively. The discharge pattern closely follows the air temperature. The long-term observation on the ‘Chhota Shigri – a benchmark glacier’, shows a mass wastage which corresponds to the slowdown of the glacier in the past two decades.
We present the first-ever mass-balance (MB) observation (2014–19), reconstruction (between 1978 and 2019) and sensitivity of debris-free Stok glacier (33.98°N, 77.45°E), Ladakh Region, India. In-situ MB was negative throughout the study period except in 2018/19 when the glacier witnessed a balanced condition. For MB modelling, three periods were considered based on the available data. Period I (1978–87, 1988/89) witnessed a near balance condition (−0.03 ± 0.35 m w.e. a−1) with five positive MB years. Whereas Period II (1998–2002, 2003–09) and III (2011–19) experienced high (−0.9 ± 0.35 m w.e. a−1) and moderate (−0.46 ± 0.35 m w.e. a−1) negative MBs, respectively. Glacier area for these periods was derived from the Corona, Landsat and PlanetScope imageries using a semi-automatic approach. The in-situ and modelled MBs were in good agreement with RMSE of 0.23 m w.e. a−1, R2 = 0.92, P < 0.05. The average mass loss was moderate (−0.47 ± 0.35 m w.e. a−1) over 28 hydrological years between 1978 and 2019. Sensitivity analysis showed that the glacier was more sensitive to summer temperature (−0.32 m w.e. a−1 °C−1) and winter precipitation (0.12 m w.e. a−1 for ± 10%). It was estimated that ~27% increase in precipitation is required on Stok glacier to compensate for the mass loss due to 1°C rise in temperature.
Cold-sprayed high-entropy alloy (HEA) coatings have been generated for the first time. Mechanically alloyed (MA) AlCoCrFeNi powder was chosen as feedstock, owing to the extensive literature on this alloy. Coatings were synthesized under various gas temperature and pressure conditions. Isothermal oxidation was conducted at 1100 °C for 25 h on the coating cold-sprayed at 400 °C and 10 bar on a Ni-base superalloy substrate. The as-sprayed coating retained the MA phases and formed a protective alumina layer upon oxidation. An interdiffusion zone at the interface and unanticipated Mo diffusion from the superalloy substrate into the coating were observed after oxidation. A comprehensive characterization at the coating–substrate interface suggests that diffusion in HEAs is not sluggish. The factors governing the coating’s oxidation are elucidated, and a plausible oxidation mechanism is discussed. These studies are aimed at developing oxidation-resistant HEA coatings for potential applications at high operating temperatures.
In this paper, a miniaturized open-ended dual-band band-pass filter with stepped series capacitance and shunt meandered line inductance for microwave frequency applications has been designed and discussed. In order to offer ease of fabrication and uniplanar configuration, coplanar waveguide feeding arrangement has been used. Zeroth order resonance, a special phenomenon of composite right/left handed transmission line has been utilized to miniaturize the filter size. The designed filter structure offers miniaturization with overall footprint size of 0.26λg × 0.19λg, where λg is the guided wavelength at the center frequency of 1.46 GHz. It offers 58.90% (1.03–1.89 GHz) and 25.93% (2.55–3.31 GHz) measured −3 dB fractional bandwidth with respect to the center frequencies of 1.46 and 2.93 GHz, respectively. Dispersion plot has been utilized to discuss the metamaterial properties for the proposed dual-band band-pass filter. In addition to above, the proposed filter structure presents almost flat group delay curve within both passbands. The proposed filter structure can be suitably utilized for distinct wireless applications, for example global navigation satellite system (1.559–1.610 GHz), GSM1800 (1.7–1.8 GHz), Wi-MAX (2.5–2.7 GHz), and naval radar and air traffic control (2.7–2.9 GHz).
In this paper, a compact metamaterial inspired ultra-thin polarization independent quad-band microwave absorber for electromagnetic interference (EMI)/ electromagnetic compatibility (EMC) applications have been discussed. The proposed absorber structure offers four different absorption peaks having absorptivity of 97.02, 94.07, 91.72, and 98.20% at 3.40, 8.23, 9.89, and 11.80 GHz, respectively. Due to the four-fold symmetry of the designed unit cell, the proposed absorber structure shows polarization independent behavior. In addition to above, the absorption curve for the designed structure has been also analyzed under different angles of incidence for both transverse electric and transverse magnetic polarization states. In order to confirm the metamaterial behavior of the proposed absorber unit cell, dispersion plot has been studied. Further, input impedance plot, electric field, and surface current distribution plot have been discussed to explain the absorption mechanism of the proposed absorber structure. The designed absorber unit cell shows compactness of 0.136 λ0 × 0.136 λ0 with the ultra-thin thickness of 0.0113 λ0, where λ0 (free space wavelength) corresponds to the lowest absorption peak of 3.40 GHz. In order to calculate the measured value of absorptivity, the designed absorber structure has been fabricated. Further, it has been observed that simulated and measured results perfectly match with each other. The ultra-thin and compact nature of the proposed absorber structure suggests its potential use in the field of various EMI/EMC applications.
Interrupted aortic arch is a rare congenital anomaly in newborns and infants and is commonly associated with other cardiovascular anomalies. Here, we report an unusual case of type A interrupted cervical aortic arch associated with long segment coarctation of the descending thoracic aorta. Patent ductus arteriosus reconstituted the descending thoracic aorta. Proximal segments of the left common carotid and left subclavian arteries were atretic. Echocardiography-gated multidetector CT angiography not only identified the type of aortic arch interruption in the neonate but also delineated the exact anatomical details.
Oxyspirura petrowi is a heteroxenous parasitic nematode that has been reported in high prevalences from birds in the Order Galliformes experiencing population declines in the USA. There is a paucity of information regarding the natural history O. petrowi, including the life cycle and effects of infection on wild bird populations. In order to study the life cycle of this parasite, we collected plains lubber grasshoppers (Brachystola magna) from a field location in Mitchell County, Texas. We found third-stage larvae (L3) in 37.9% (66/174) B. magna. We determined that they were O. petrowi through morphological comparison of L3 from experimentally infected Acheta domesticus and by sequence analysis. Then, we showed that B. magna are a potential intermediate hosts for O. petrowi infections in northern bobwhites (Colinus virginianus) in a laboratory setting by experimental infection. We first detected shedding of eggs in feces using a fecal float technique 52 days post infection. In addition, we recovered 87 O. petrowi from experimentally infected northern bobwhites. Although we detected shedding in feces, recovery of eggs was low (>5 eggs/g). Future work is needed to understand shedding routes and shedding patterns of northern bobwhites infected with O. petrowi.
Iron (Fe) and zinc (Zn) contents in hexaploid wheat are very low and are further reduced because of the removal of micronutrient-rich bran of wheat grains during milling and processing. Therefore, hexaploid wheat, its wild species and wheat–Aegilops kotschyi substitution lines were evaluated to identify the genome(s) carrying gene(s) for high Fe and Zn concentrations in bran and endosperm fractions of grains. It is reflected from the results that Triticum monococcum (acc. W463) may serve as a promising donor for biofortification of Fe, and Aegilops speltoides (acc. 3804) may serve as a promising donor for biofortification of Zn in the endosperm of cultivated wheat. Further, among the three wheat–Ae. kotschyi substitution lines, the higher concentration of Fe and Zn in endosperm fraction was observed in BC2F4 63-2-13-1. The work on precise transfer of useful gene(s) from 7Uk chromosome of this line is in progress to reduce linkage drag.