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1.
Nanoscale Horiz ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958571

RESUMO

The growth of graphene on a metal substrate using chemical vapor deposition (CVD), assisted by hydrocarbons such as CH4, C3H8, C2H6, etc. leads to the formation of carbon clusters, amorphous carbon, or any other structure. These carbon species are considered as unwanted impurities; thus a conventional etching step is used simultaneously with CVD graphene growth to remove them using an etching agent. Meanwhile, art etching is a specific method of producing controlled non-Euclidean and Euclidean geometries by employing intricate and precise etching parameters or integrated growth/etching modes. Agents such as H2, O2, CH4, Ar, and others are applied as art etching agents to support the art etching technology. This technique can generate nanopores and customize the properties of graphene, facilitating specific applications such as nanodevices, nanosensors, nanofilters, etc. This comprehensive review investigates how precursor gases concurrently induce graphene growth and art etching during a chemical vapor deposition process, resulting in beautifully etched patterns. Furthermore, it discusses the techniques leading to the creation of these patterns. Finally, the challenges, uses, and perspectives of these non-Euclidean and Euclidean-shaped art etched graphene geometries are discussed.

2.
Curr Opin Environ Sci Health ; 28: 100373, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35669052

RESUMO

The coronaviruses are the largest known RNA viruses of which SASR-CoV-2 has been spreading continuously due to its repeated mutation triggered by several environmental factors. Multiple human interventions and lessons learned from the SARS 2002 outbreak helped reduce its spread considerably, and thus, the virus was contained but the emerging mutations burdened the medical facility leading to many deaths in the world. As per the world health organization (WHO) droplet mode transmission is the most common mode of SASR-CoV-2 transmission to which environmental factors including temperature and humidity play a major role. This article highlights the responsibility of environmental causes that would affect the distribution and fate of the virus. Recent development in the risk assessment models is also covered in this article.

3.
Comput Intell Neurosci ; 2022: 1174173, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35676959

RESUMO

Patients with diabetes who are closely monitored have a higher overall quality of life than those who are not. Costs associated with healthcare can be decreased by utilising the Internet of Things (IoT), thanks to technological advancements. To satisfy the expectations of e-health applications, it is required for the development of the intelligent systems as well as increases the number of applications that are connected to the network. As a result, in order to achieve these goals, the cellular network should be capable of supporting intelligent healthcare applications that require high energy efficiency. In this paper, we model a neural network-based ensemble voting classifier to predict accurately the diabetes in the patients via online monitoring. The study consists of Internet of Things (IoT) devices to monitor the instances of the patients. While monitoring, the data are transferred from IoT devices to smartphones and then to the cloud, where the process of classification takes place. The simulation is conducted on the collected samples using the python tool. The results of the simulation show that the proposed method achieves a higher accuracy rate, higher precision, recall, and f-measure than existing state-of-art ensemble models.


Assuntos
Diabetes Mellitus , Qualidade de Vida , Simulação por Computador , Atenção à Saúde , Diabetes Mellitus/diagnóstico , Humanos , Redes Neurais de Computação
4.
Curr Opin Environ Sci Health ; 27: 100358, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35369608

RESUMO

Structural and genetic differences among various viruses play a significant factor in host infectivity and vulnerability to environmental stressors. Zoonoses of viruses require several recombinations and mutations in their genetic material and among several viruses allowing them to switch hosts and infect new species. Additionally, the host genetics play a significant role in successful viral transmission among various hosts. For example, human immunodeficiency virus (HIV), Ebola virus and influenza viruses. In efficient zoonotic events, selective stresses in the host milieu-interieur are critical during viral infection of the first human host. The genetic rearrangement of the virus and the selective environmental pressure of the host immune system dominate the emergence of new viral disease outbreaks.

5.
Nanotechnology ; 33(7)2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34736237

RESUMO

MoS2is an intrinsic piezoelectric material which offers applications such as energy harvesting, sensors, actuators, flexible electronics, energy storage and more. Surprisingly, there are not any suitable, yet economical methods that can produce quality nanosheets of MoS2in large quantities, hence limiting the possibility of commercialisation of its applications. Here, we demonstrate controlled synthesis of highly crystalline MoS2nanosheets via liquid phase exfoliation of bulk MoS2, following which we report piezoelectric response from the exfoliated nanosheets. The method of piezo force microscopy was employed to explore the piezo response in mono, bi, tri and multilayers of MoS2nanosheets. The effective piezoelectric coefficient of MoS2varies from 9.6 to 25.14 pm V-1. We attribute piezoelectric response in MoS2nanosheets to the defects formed in it during the synthesis procedure. The presence of defects is confirmed by x-ray photoelectron spectroscopy.

6.
J Environ Manage ; 288: 112340, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33823437

RESUMO

Photocatalytic removal of estrogenic compounds (ECs), 17ß-estradiol (E2), and 17α-ethinylestradiol (EE2) were assessed using a TiO2-ZnO nanocomposite (NC) over a range of initial EC concentration (Co; 10 mg/L - 0.05 mg/L). Photocatalytic removal was evaluated under UV and visible irradiation using 10 mg/L NC over 240 min duration. After 240 min, analysis using GCxGC TOF MS revealed 100% transformation at Co ≤ 1 mg/L and ≥25% transformation at Co ≤ 10 mg/L under visible irradiation. Degradation was accompanied by breakdown of the fused ring structure of E2, generating smaller molecular weight by-products which were subsequently mineralized as revealed through TOC removal. With UV photocatalysis, ~30% and ~20% mineralization was attained for E2 and EE2, respectively, for Co of 10 mg/L. Under visible irradiation, ~25% and ~10% mineralization was achieved for E2 and EE2, respectively. Estrogenicity variation was estimated using the E-screen assay conducted with estrogen receptor-positive MCF-7 breast cancer cells. Complete removal of estrogenicity of ECs was confirmed after 240 min of photocatalysis under UV and visible irradiation. FTIR spectroscopy-based analysis of the NC after E2 photocatalysis revealed the presence of sorbed organics. Desorption, followed by GC × GC TOF-MS analysis revealed these organics as by-products of photocatalysis. Desorption of sorbed organics followed by recalcination at 600 °C for 1 h regenerated the active sites on the NC, enabling its efficient reuse for 3 cycles under visible irradiation without loss in activity.


Assuntos
Poluentes Químicos da Água , Óxido de Zinco , Estradiol , Estrogênios , Etinilestradiol/análise , Titânio , Água , Poluentes Químicos da Água/análise
7.
Sci Total Environ ; 765: 142746, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33092831

RESUMO

The contagious SARS-CoV-2 virus, responsible for COVID-19 disease, has infected over 27 million people across the globe within a few months. While literature on SARS-CoV-2 indicates that its transmission may occur predominantly via aerosolization of virus-laden droplets, the possibility of alternate routes of transmission and/or reinfection via the environment requires considerable scientific attention. This review aims to collate information on possible transmission routes of this virus, to ascertain its fate in the environment. Concomitant with the presence of SARS-CoV-2 viral RNA in faeces and saliva of infected patients, studies also indicated its occurrence in raw wastewater, primary sludge and river water. Therefore sewerage system could be a possible route of virus outbreak, a possible tool to assess viral community spread and future surveillance technique. Hence, this review looked into detection, occurrence and fate of SARS-CoV-2 during primary, secondary, and tertiary wastewater and water treatment processes based on published literature on SARS-CoV and other enveloped viruses. The review also highlights the need for focused research on occurrence and fate of SARS-CoV-2 in various environmental matrices. Utilization of this information in environmental transmission models developed for other enveloped and enteric viruses can facilitate risk assessment studies. Preliminary research efforts with SARS-CoV-2 and established scientific reports on other coronaviruses indicate that the threat of virus transmission from the aquatic environment may be currently non-existent. However, the presence of viral RNA in wastewater provides an early warning that highlights the need for effective sewage treatment to prevent a future outbreak of SARS-CoV-2.


Assuntos
COVID-19 , Purificação da Água , Atenção , Humanos , Pandemias , SARS-CoV-2 , Águas Residuárias
8.
Ecol Evol ; 8(12): 6253-6264, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29988446

RESUMO

The mountain pine beetle (Dendroctonus ponderosae) is an insect native to western North America; however, its geographical range has recently expanded north in BC and east into Alberta. To understand the population structure in the areas of expansion, 16 gene-linked microsatellites were screened and compared to neutral microsatellites using outlier analyses of Fst and Fct values. One sex-linked gene, inhibitor of apoptosis (IAP), showed a strong signature of positive selection for neo-X alleles and was analyzed for evidence of adaptive variation. Alleles of IAP were sequenced, and differences between the neo-X and neo-Y alleles were consistent with neutral evolution suggesting that the neo-Y allele may not be under functional constraints. Neo-Y alleles were amplified from gDNA, but not effectively from cDNA, suggesting that there was little IAP expression from neo-Y alleles. There were no differences in overall IAP expression between males and females with the common northern neo-X allele suggesting that the neo-X allele in males compensates for the reduced expression of neo-Y alleles. However, males lacking the most common northern neo-X allele thought to be selected for in northern populations had reduced overall IAP expression in early October-at a time when beetles are preparing for overwintering. This suggests that the most common allele may have more rapid upregulation. The reduced function of neo-Y alleles of IAP suggested by both sequence differences and lower levels of expression may foster a highly selective environment for neo-X alleles such as the common northern allele with more efficient upregulation.

9.
Mol Biol Cell ; 29(2): 123-136, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29167383

RESUMO

Tricellular junctions (TCJs) are uniquely placed permeability barriers formed at the corners of polarized epithelia where tight junctions in vertebrates or septate junctions (SJ) in invertebrates from three cells converge. Gliotactin is a Drosophila TCJ protein, and loss of Gliotactin results in SJ and TCJ breakdown and permeability barrier loss. When overexpressed, Gliotactin spreads away from the TCJs, resulting in disrupted epithelial architecture, including overproliferation, cell delamination, and migration. Gliotactin levels are tightly controlled at the mRNA level and at the protein level through endocytosis and degradation triggered by tyrosine phosphorylation. We identified C-terminal Src kinase (Csk) as a tyrosine kinase responsible for regulating Gliotactin endocytosis. Increased Csk suppresses the Gliotactin overexpression phenotypes by increasing endocytosis. Loss of Csk causes Gliotactin to spread away from the TCJ. Although Csk is known as a negative regulator of Src kinases, the effects of Csk on Gliotactin are independent of Src and likely occur through an adherens junction associated complex. Overall, we identified a new Src-independent role for Csk in the control of Gliotactin, a key tricellular junction protein.


Assuntos
Junções Aderentes/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Quinases da Família src/metabolismo , Animais , Proteína Tirosina Quinase CSK , Proteínas de Drosophila/genética , Drosophila melanogaster/metabolismo , Endocitose/genética , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Fosforilação , Junções Íntimas/metabolismo , Quinases da Família src/genética
10.
J Clin Diagn Res ; 7(8): 1725-6, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24086892

RESUMO

Cutaneous lesions are a part of common manifestation in multi-systemic sarcoidosis and skin involvement occurs in 20% to 35% of the patients with systemic disease. An exclusive cutaneous involvement is rare and it is reported in about 4%-5% of the patients of sarcoidosis. These lesions have been classified into specific and non-specific, depending on the presence of non- caseating granulomas, on histopathologic studies. In the present study, we are reporting two cases of isolated cutaneous sarcoidosis without systemic manifestations, which is a rare presentation. Sarcoidosis will continue to challenge even the most experienced clinicians with respect to a high degree of suspicion and further investigations for diagnosing and treating this disorder.

11.
J Clin Diagn Res ; 6(10): 1672-4, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23373025

RESUMO

BACKGROUND: Cytologists are often under time pressure due to a constant need and a demand for quick despatch of reports, which calls for an early assessment of sample adequacy. OBJECTIVE: To study whether unstained smears are effective in evaluation of sample adequacy of cytology aspirates. MATERIALS AND METHODS: The study had 3 groups. Assessment of sample adequacy of cytology aspirates was done on unstained smears in Group I (200 cases), Group II (100 cases out of Group I) and Group III ( 80 cases out of Group II ) by a Professor, Assistant Professor and a junior resident respectively. The results were compared with assessment of adequacy on stained smears and statistical analysis was done. RESULTS: Evaluation of adequacy of cytology aspirates by examination of unstained and stained smears by 3 observers of varied experience revealed no significant difference between the observers and between the stained and unstained smears (p<0.001). CONCLUSION: Unstained smear study offered advantages over the stained smears in the evaluation of sample adequacy. Hence, it maybe recommended as a routine practice in cytology clinics.

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