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In the current scenario of the coronavirus pandemic caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), considerable efforts have been made to control the pandemic by the development of a strong immune system through massive vaccination. Just after the discovery of the genetic sequences of SARS-CoV-2, the development of vaccines became the prime focus of scientists around the globe. About 200 SARS-CoV-2 candidate vaccines have already been entered into preclinical and clinical trials. Various traditional and novel approaches are being utilized as a broad range of platforms. Viral vector (replicating and non-replicating), nucleic acid (DNA and RNA), recombinant protein, virus-like particle, peptide, live attenuated virus, an inactivated virus approaches are the prominent attributes of the vaccine development. This review article includes the current knowledge about the platforms used for the development of different vaccines, their working principles, their efficacy, and the impacts of COVID-19 vaccines on thrombosis. We provide a detailed description of the vaccines that are already approved by administrative authorities. Moreover, various strategies utilized in the development of emerging vaccines that are in the trial phases along with their mode of delivery have been discussed along with their effect on thrombosis and gastrointestinal disorders.
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COVID-19 , Gastroenteropatias , Trombose , Vacinas Virais , Humanos , Vacinas contra COVID-19 , COVID-19/prevenção & controle , SARS-CoV-2/genética , Vacinas Virais/uso terapêutico , Gastroenteropatias/prevenção & controle , Gastroenteropatias/tratamento farmacológico , Trombose/prevenção & controle , Trombose/tratamento farmacológicoRESUMO
The boiling crisis or critical heat flux (CHF) is a very critical constraint for any heat-flux-controlled boiling system. The existing methods (physical models and empirical correlations) offer a specific interpretation of the boiling phenomenon, as many of these correlations are considerably influenced by operational variables and surface morphologies. A generalized correlation is virtually unavailable. In this study, more physical mechanisms are incorporated to assess CHF of surfaces with micro- and nano-scale roughness subject to a wide range of operating conditions and working fluids. The CHF data is also correlated by using the Pearson, Kendal, and Spearman correlations to evaluate the association of various surface morphological features and thermophysical properties of the working fluid. Feature engineering is performed to better correlate the inputs with the desired output parameter. The random forest optimization (RF) is used to provide the optimal hyper-parameters to the proposed interpretable correlation and experimental data. Unlike the existing methods, the proposed method is able to incorporate more physical mechanisms and relevant parametric influences, thereby offering a more generalized and accurate prediction of CHF (R2 = 0.971, mean squared error = 0.0541, and mean absolute error = 0.185).
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Extensive amount of research on additively manufactured (AM) lattice structures has been made to develop a generalized model that can interpret how strongly operational variables affect mechanical properties. However, the currently used techniques such as physics models and multi-physics simulations provide a specific interpretation of those qualities, and are not general enough to assess the mechanical properties of AM lattice structures of different topologies produced on different materials via several fabrication methods. To tackle this problem, this study develops an optimal deep learning (DL) model based on more than 4000 data points, which has been optimized by analyzing three different hyper-parameters optimization schemes including gradient boost regression trees (GBRT), gaussian process (GP), and random forest (RF) with different data distribution schemes such as normal distribution, nth root transformation, and robust scaler. With the robust scaler and nth root transformation, the accuracy of the model increases from R2 = 0.85 (for simple distribution) to R2 = 0.94 and R2 = 0.88, respectively. After feature engineering and data correlation, the stress, unit cell size, total height, width, and relative density are chosen to be the input parameters to model the strain. The optimal DL model is able to predict the strain of different topologies of lattices (such as circular, octagonal, Gyroid, truncated cube, Truncated cuboctahedron, Rhombic do-decahedron, and many others) with decent accuracy (R2 = 0.936, MAE = 0.05, and MSE = 0.025). The parametric sensitivity analysis and explainable artificial intelligence (by using DeepSHAP library) based insights confirm that stress is the most sensitive input to the strain followed by the relative density from the modeling perspective of the AM lattices. The findings of this study would be helpful for the industry and the researchers to design AM lattice structures of different topologies for various engineering applications.
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The present study develops a deep learning method for predicting the boiling heat transfer coefficient (HTC) of nanoporous coated surfaces. Nanoporous coated surfaces have been used extensively over the years to improve the performance of the boiling process. Despite the large amount of experimental data on pool boiling of coated nanoporous surfaces, precise mathematical-empirical approaches have not been developed to estimate the HTC. The proposed method is able to cope with the complex nature of the boiling of nanoporous surfaces with different working fluids with completely different thermophysical properties. The proposed deep learning method is applicable to a wide variety of substrates and coating materials manufactured by various manufacturing processes. The analysis of the correlation matrix confirms that the pore diameter, the thermal conductivity of the substrate, the heat flow, and the thermophysical properties of the working fluids are the most important independent variable parameters estimation under consideration. Several deep neural networks are designed and evaluated to find the optimized model with respect to its prediction accuracy using experimental data (1042 points). The best model could assess the HTC with an R2 = 0.998 and (mean absolute error) MAE% = 1.94.
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Cerium oxide nanoparticles (nanoceria) were synthesized by a novel, simple green chemistry procedure using Elaeagnus angustifolia leaf extract as a reducing and capping agent. The crystalline nature of nanoceria was confirmed by XRD analysis. FTIR analysis revealed that phytochemicals are present on the surface of nanoceria. SEM and TEM images revealed that the nanoceria are well dispersed, spherical in shape with a particle size range in between 30 and 75â¯nm. Thereafter, the effects of various concentrations of cerium oxide (CeO2) and green synthesized nanoceria on growth and metabolism of Solanum lycopersicum (tomato) were investigated. The bio-accumulation of Ce in tomato seedlings was found to be dose dependent and the results showed that with the increase in exposure concentrations, the accumulation of Ce contents in both root and shoots augmented. However, unlike nanoceria treated seedlings, Ce contents in the roots with CeO2 treatments were negligible than that in the shoots at lower concentrations and this suggested the immobilization of Ce in CeO2 treatment at lower concentrations. Nanoceria at 500 and 1000â¯mg/L resulted in inhibitory effect on growth of test plant as compared to CeO2 component. The exposure of plants to nanoceria and CeO2 has resulted in significant reduction in pigment content, increased LP, EL and H2O2 content. The activities of antioxidant enzymes viz. SOD, CAT, APX and GPX were significantly up regulated on exposure of nanoceria and CeO2. It is concluded that plant exposure with nanoceria at concentrations of 20 and 100â¯mg/L were more beneficial for growth and metabolism of tomato plants than that of CeO2 at equivalent concentrations.
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Antioxidantes/metabolismo , Cério/farmacologia , Química Verde/métodos , Nanopartículas/química , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/enzimologia , Transporte Biológico , Cério/química , Cério/metabolismo , Elaeagnaceae/química , Peróxido de Hidrogênio/metabolismo , Tamanho da Partícula , Extratos Vegetais/químicaRESUMO
Study on the ecological effect of metal oxide nanomaterials (NMs) has quickly amplified over the precedent years because it is assumed that these NMs will sooner or later be released into the environment. The present study deals with biologically oriented process for the green synthesis of copper oxide nanoparticles (CuO NPs) by using Morus alba leaf extract as reducing agent. Powder X-ray diffraction (XRD) and transmission electron microscope (TEM) analysis revealed the monoclinic phase and 20-40nm size respectively. The presence of reducing and capping agents revealed by Fourier transform infrared (FTIR) spectroscopy. The seedlings of Brassica oleracea var. botrytis and Solanum lycopersicum were exposed to 10, 50, 100, and 500mgL-1 concentrations of CuO NPs in the sand medium. Bioaccumulation of Cu was also investigated by atomic absorption spectroscopy (AAS). Plant exposure to 100 and 500mgL-1 of CuO NPs has resulted in significant reduction of total chlorophyll and sugar content in the two test plants while 10mgL-1 of NPs slightly increased the pigment and sugar content in tomato plants only. Augmentation of lipid peroxidation, electrolyte leakage, and antioxidant enzyme activity was observed in a dose dependent manner upon plants exposure to CuO NPs. Deposition of lignin in roots of both plants treated with the highest concentration of CuO NPs was observed. Histochemical analysis of leaves of treated plant with nitroblue tetrazolium and 3'3' diaminobenzidine showed a concentration dependent increase in superoxide and hydrogen peroxide formation in leaves. The green synthesis of CuO NPs was carried out by using Morus alba leaf extract. Accumulation of NPs more actively by tomato plants as compared to cauliflower was possibly due to the difference in root morphology. The histochemical visualization highlights the spatial organization of oxidant biochemistry occurring in response to metal stress.
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Brassica/efeitos dos fármacos , Cobre/metabolismo , Nanopartículas Metálicas/química , Solanum lycopersicum/efeitos dos fármacos , Antioxidantes , Brassica/crescimento & desenvolvimento , Catalase/análise , Clorofila/análise , Cobre/análise , Cobre/química , Cobre/farmacologia , Eletrólitos , Química Verde/métodos , Peroxidação de Lipídeos , Solanum lycopersicum/crescimento & desenvolvimento , Microscopia Eletrônica de Transmissão , Morus/química , Nitrato Redutase/metabolismo , Fotossíntese , Extratos Vegetais/química , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/citologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Plântula , Espectroscopia de Infravermelho com Transformada de Fourier , Açúcares/análise , Superóxido Dismutase/análise , Superóxidos , Difração de Raios XRESUMO
INTRODUCTION: Rolando fractures being intra-articular fractures of the most mobile joint of the thumb, assume significance because any residual incongruity of the articular surface may result in loss of motion as well as secondary osteoarthritis and hence serious disability. This fracture continues to pose difficulties to the treating surgeons and although several treatment options have been described for these fractures, there are no definite guidelines. METHODS: The present study describes the results of open reduction and internal fixation of nine Rolando fractures with large and single fragments, using mini T-plate and screws. RESULTS: At 3-year follow-up all the fractures had united, functional results were excellent or good in most cases, and all the patients had returned to previous activities. Significant complications such as deep infection and loss of reduction were not encountered in any patient. CONCLUSION: Open reduction and internal fixation with mini T-plates in properly selected cases of Rolando fracture with large and single palmar and dorsal articular fragments offers several advantages such as allowing direct visualization of the joint, removal of interposed soft tissues, and exact anatomical restoration of the articular surface. The fixation in most cases is rigid enough to allow early mobilization without loss of reduction. Thus, complications such as stiffness as well as future arthrosis may be minimized. However, the technique is demanding and needs high degree of precision. The possibility of implant removal should be discussed beforehand with the patient.
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In the present study, zinc oxide nanoparticles (ZnO NPs) were rapidly synthesized at room temperature by treating zinc acetate dihydrate with the flower extract of Elaeagnus angustifolia (Russian olive). The formation of ZnO NPs was primarily confirmed by UV-visible absorption spectrum in the range of 250-700nm. XRD analysis and DLS particle size analyzer revealed the size of ZnO NPs. The FTIR spectrum revealed the presence of phytochemicals in the flower extract mediated ZnO NPs. Moreover, the morphology of the ZnO NPs was determined using SEM. Seeds of Solanum lycopersicum (tomato) were separately treated with different concentrations of synthesized ZnO NPs and zinc sulphate (ZnSO4) salt suspensions (common zinc supplement). The effect of these treatments on seed germination, seedling vigor, chlorophyll, protein and sugar contents as well as on the activities of lipid peroxidation and antioxidant enzyme were studied. Leaves of plants treated with 6.1mM concentration of ZnO NPs recorded maximum reflectance while it was minimum in plants treated with 1.2mM concentration of NPs. The effect of synthesized ZnO NPs on seedling vigor, pigment, protein and sugar content was found affirmative at lower concentrations contrary to control and ZnSO4 salt. The inhibitory effect at higher concentration of NPs indicated importance in the precise application of NPs, in Zn deficient system, where plant response varies with concentration. To the best of our knowledge this is the first report on Elaeagnus angustifolia mediated synthesis of ZnO NPs and their effects on germination and physiological activity of tomato.
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Germinação/efeitos dos fármacos , Nanopartículas Metálicas/química , Extratos Vegetais/química , Solanum lycopersicum/efeitos dos fármacos , Óxido de Zinco/química , Elaeagnaceae/química , Flores/química , Química Verde , Solanum lycopersicum/metabolismo , Nanopartículas Metálicas/toxicidade , Folhas de Planta/química , Sementes/efeitos dos fármacos , Óxido de Zinco/metabolismoRESUMO
Nanotechnology is a new and emerging technology with wealth of applications. It involves the synthesis and application of materials having one of the dimensions in the range of 1-100 nm. A wide variety of physico-chemical approaches are being used these days for the synthesis of nanoparticles (NPs). However, biogenic reduction of metal precursors to produce corresponding NPs is eco-friendly, less expensive, free of chemical contaminants for medical and biological applications where purity of NPs is of major concern. Biogenic reduction is a "Bottom Up" approach similar to chemical reduction where a reducing agent is replaced by extract of a natural products with inherent stabilizing, growth terminating and capping properties. Furthermore, the nature of biological entities in different concentrations in combination with reducing organic agents influence the size and shape of NPs. Present review focuses on microbes or plants based green synthesis of Ag, Au, Cu, Fe, Pd, Ru, PbS, CdS, CuO, CeO2, Fe3O4, TiO2, and ZnO NPs and their potential applications.
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Química Verde/métodos , Nanopartículas Metálicas/química , Nanotecnologia/métodos , Extratos Vegetais/química , SemicondutoresRESUMO
This work aimed to study the pattern and epidemiology of pediatric musculoskeletal trauma and consequent morbidity in Kashmir Valley and compare the results with other studies and to formulate preventive measures and devise management strategies. This was a retrospective study of 1467 pediatric orthopedic trauma patients who presented to our hospital over a 3-year period between September 2005 and August 2008. Information was recorded in a prescribed proforma including the following: age, sex, mode of trauma, type of fracture/injury, radiological study, final diagnosis, intervention performed, and complications. The information was collected from the Medical Records Department of the hospital. The children's ages ranged from 0 to 16 years; there were 996 males and 471 females, with males outnumbering females in every age group (the overall male-to-female ratio was 2.12:1). Most fractures occurred in children aged 7-12 years [n=816 (53.96%)] and decreased in younger and older children beyond this age group. The left side was involved in 762 cases, 612 injuries involved the right side, 24 were bilateral, and 69 patients presented with multiple injuries. In children aged 0-6 years, the most common site of injury was the elbow, whereas in children aged 7-16 years, it was the forearm. In descending order, most injuries were sustained because of fall while playing (34.76%), fall from height (33.74%), road traffic accidents (14.92%), and fall from standing height (7.97%). The majority of injuries were caused by unintentional trauma (94.48 vs. 5.52%). The places where injury occurred were the home [603 (41.10%)], play field and orchards near the home [450 (30.67%)], roads [219 (14.92%)], school [183 (12.47%)], and unknown [12 (0.81%)]. The pattern and epidemiology of pediatric trauma differs from those in adults. The majority of musculoskeletal injuries are because of unintentional trauma in this young age group and hence preventable. Enhanced supervision at home and school is recommended. A safer environment and better playing conditions may decrease the high frequency of trauma in pediatric patients. Dedicated trauma centers with such facilities as orthopedics, neurosurgery, and plastic surgery need to be established for the proper management of pediatric trauma.