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1.
Opt Express ; 32(3): 4376-4386, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297640

RESUMO

Numerical analysis of Dyakonov waves generation has been carried out at uniaxial chiral-plasma planar interface. The extended electromagnetic wave theory is utilized, and an impedance boundary conditions approach is employed to obtain characteristics equation. Effective mode index and attenuation under the different values of collisional frequency, plasma frequency and chirality in the THz frequency range for three cases for uniaxial chiral media are discussed. These results can be used in the field of photonics and integrated optics to fabricate nanophotonic devices in the THz frequency range.

2.
Dement Geriatr Cogn Disord ; : 1-17, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38636474

RESUMO

INTRODUCTION: Vascular dementia (VaD), a neurocognitive impairment directly related to vascular injury, is the second most common cause of age-related dementia. Although numerous studies have investigated candidate genetic polymorphisms associated with VaD in Asia, the genetics of VaD remains unclear. METHODS: This review provides an updated meta-analysis of genetic polymorphisms associated with VaD in Asians, using the PRISMA guidelines. Published literature up to May 2021 was extracted from the PubMed, Scopus, Ovid, and EBSCOhost databases. Meta-analysis was conducted using the Open Meta analyst, Review Manager, and MedCalc® Statistical Software. Trial sequential analysis (TSA) was performed using TSA viewer software. RESULTS: A total of 46 eligible studies, comprising 23 genes and 35 single nucleotide polymorphisms, were retrieved. The meta-analysis was conducted on the following genetic polymorphisms, APOE ε2/3/4, MTHFR rs1801131, ACE rs4340 (I/D) gene polymorphism, and a PSEN1 intron 8 variant. The pooled odds ratio (ORs) revealed a significant increase in the risk of VaD in the apolipoprotein E (APOE) ε4 allelic model (OR, 1.79, p < 0.001), and the methylenetetrahydrofolate reductase (MTHFR) rs1801133 polymorphism T allele in the allelic model (OR, 1.23, p = 0.013). CONCLUSION: Our findings provide evidence that genetic polymorphisms of the APOE ε4 allele and MTHFR rs1801133 T allele increase the risk of developing VaD in Asians. However, future large-scale investigations examining particularly on South-Eastern and West-Asian populations are highly recommended.

3.
J Opt Soc Am A Opt Image Sci Vis ; 38(4): 465-475, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33798175

RESUMO

In this work, the theoretical study of the interaction of terahertz (THz) waves with graphene embedded into two different semi-infinite metamaterials was carried out. To model the graphene, the effective surface conductivity approach based on the Kubo formalism was used. In addition, two types of metamaterials, i.e., double-positive (DPS) and double-negative (DNG), were studied in the THz regime. The numerical modeling of metamaterials was performed in the framework of causality-principle-based Kramers-Kronig relations. The reflectance and transmittance from the graphene-embedded metamaterial structures are studied for the following four different configurations: DPS-Graphene-DPS, DPS-Graphene-DNG, DNG-Graphene-DPS, and DNG-Graphene-DNG. The influence of the chemical potential and scattering rate on the reflectance and transmittance for each configuration is analyzed. It is concluded that the DPS-Graphene-DPS and DNG-Graphene-DNG configurations behave as anti-reflectors for the THz waves, while the DPS-Graphene-DNG and DNG-Graphene-DPS configurations are suitable for THz reflector applications. Moreover, a parametric study revealed that the relative permittivity of the partnering metamaterial can be used as an additional degree of freedom to control the reflectance and transmittance of THz waves. In conclusion, the transmissive and reflective characteristics of THz waves can be controlled effectively with the appropriate choice of graphene parameters, as well as the configuration of metamaterial structures. The convergence of the analytical and numerical results is found with the published results under special conditions. The present work may have potential applications in the design of THz wave controllers, reflectors, absorbers, and anti-reflectors.

4.
Med J Malaysia ; 75(3): 311-313, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32467554

RESUMO

On the 18th of March 2020, the Malaysia government declared a movement control order (MCO) due to the unprecedented COVID-19 pandemic. Although the majority of patients presented with respiratory-related symptoms, COVID-19 patients may present atypically with neurological manifestations and may even have an increased risk of stroke. The Malaysia Stroke Council is concerned regarding the level of care given to stroke patients during this pandemic. During the recent National Stroke Workflow Steering Committee meeting, a guide was made based on the currently available evidences to assist Malaysian physicians providing acute stroke care in the hospital setting in order to provide the best stroke care while maintaining their own safety. The guide comprises of prehospital stroke awareness, hyperacute stroke care, stroke care unit and intensive care unit admission, post-stroke rehabilitation and secondary prevention practice. We urge continuous initiative to provide the best stroke care possible and ensure adequate safety for both patients and the stroke care team.


Assuntos
Betacoronavirus , Infecções por Coronavirus/complicações , Pandemias , Pneumonia Viral/complicações , Acidente Vascular Cerebral/terapia , COVID-19 , Humanos , Unidades de Terapia Intensiva , Malásia , Guias de Prática Clínica como Assunto , SARS-CoV-2 , Acidente Vascular Cerebral/diagnóstico por imagem , Reabilitação do Acidente Vascular Cerebral , Tomografia Computadorizada por Raios X
5.
Vavilovskii Zhurnal Genet Selektsii ; 28(3): 326-331, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38952703

RESUMO

Frank-Ter Haar syndrome (FTHS) is a rare genetic hereditary autosomal recessive disorder characterized by defective malformation of cardiovascular, craniofacial, and skeletal system. Mutations in the SH3PXD2B gene are a common cause in the development of FTHS. We recruited a family with two affected individuals (3-year-old female and 2-month-old male infant) having bilateral clubfoot. Family pedigree shows an autosomal recessive mode of inheritance. DNA was extracted from the blood samples of six members of the family. Whole exome sequencing was done for the two affected individuals and the variant was validated in the whole family by using Sanger sequencing approach. Whole exome sequencing (WES) data analysis identified a rare homozygous variant (c.280C>G; p.R94G) in the SH3PXD2B gene, and Sanger sequencing showed that the same variant perfectly segregates with the phenotype in the pedigree. Moreover, the variant is predicted to be damaging and deleterious by several computation tools. Revisiting the family members for detailed clinical analysis, we diagnosed the patients as having the typical phenotype of FTHS. This study enabled us to correctly diagnose the cases of FTHS in a family initially recruited for having bilateral clubfoot by using WES. Moreover, this study identified a novel homozygous missense variant (c.280C>G; p.R94G) in (NM_001308175.2) the SH3PXD2B gene as a causative variant for autosomal recessive FTHS. This finding supports the evidence that homozygous mutations in the SH3PXD2B gene are the main cause in the development of FTHS.

6.
Indian J Clin Biochem ; 28(2): 185-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24426207

RESUMO

The study has been undertaken as number of sickle cell patients in Chhattisgarh tribal population is 23.7 %. The Co enzyme Q10 is a strong antioxidant and energy producing compound. The patients were divided into three groups group A homozygous (SS), group B heterozygous (AS) and group C controls for TBARS study. The age group is 10-55 years and 200 mg of CoQ10 was given to A and B groups. The hematological parameters, C reactive protein as well as RBC TBARS level were performed by usual and standard techniques. The results were obtained as 25.37 % increased RBC level in group A and 23.24 % in group B. The increased hemoglobin level was observed as 16.73 % in group A and 10.7 % in group B. In case of WBC it was observed increased 24.38 % in group A and 12.0 % in group B. C-reactive protein was observed 7.8 times decreased in group A and 1.54 times in group B. The RBC TBARS level was also found decreased 48 % in group A and 51 % in group B as compared to group C. During the supplementation of coenzyme Q10 the pain caused by vaso-occlusive events has reduced. This significant increase in hematological parameters as well as decreased C-reactive protein and TBARS level suggest that the Q10 should be included in the diet of sickle cell patients.

7.
Eur Arch Paediatr Dent ; 24(6): 787-795, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37848680

RESUMO

PURPOSE: Understanding the impact of coronavirus disease-2019 (COVID-19) pandemic social restrictions on the lives of children and adolescents is of utmost importance to enable timely diagnosis and treatment. Therefore, the aim of this study was to explore the prevalence of anxiety, sleep bruxism, temporomandibular disorders (TMD) and change in dietary and brushing habits and their association with COVID-19 social restrictions. METHODS: Parents of fit and healthy Qatari children and adolescents were recruited and interviewed by the research team, whereby validated questioners were used to assess the prevalence of children's/adolescents' anxiety, sleep bruxism and TMD. Furthermore, changes in dietary and brushing habits were also evaluated. RESULTS: A total of 199 parents of children and adolescents (mean age = 9.3 ± 3.2 years old) were included. Overall anxiety symptoms, sleep bruxism and TMD were evident in 29.6%, 5.7% and 23.1%, respectively. An increased consumption of food, sweets and worsening of brushing habits were evident in 51.8%, 62.8% and 31.2%, respectively. CONCLUSION: Within the limitations of this study, pandemic-related social restrictions could result in elevated levels of anxiety, specifically, social phobia, amongst children and adolescents, which could inevitably lead to unwanted dental consequences.


Assuntos
COVID-19 , Bruxismo do Sono , Transtornos da Articulação Temporomandibular , Humanos , Criança , Adolescente , Bruxismo do Sono/epidemiologia , Estudos Transversais , Prevalência , Transtornos da Articulação Temporomandibular/epidemiologia , Ansiedade/epidemiologia
8.
Microbiol Resour Announc ; 12(6): e0115122, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37154688

RESUMO

The influenza virus strain A/chicken/North Kazakhstan/184/2020 (H5N8) was isolated in North Kazakhstan during a highly pathogenic avian influenza outbreak in 2020. This study aimed to obtain the complete genome sequence of the isolate.

9.
Transpl Infect Dis ; 14(3): 248-58, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22385394

RESUMO

BACKGROUND: The optimal method of both predicting and preventing cytomegalovirus (CMV) disease in lung transplant recipients remains unclear. In particular, the most appropriate duration of CMV prophylaxis post transplant is unresolved. We report herein our experience with a planned indefinite regimen of valganciclovir prophylaxis and monitoring of quantitative CMV load in bronchoalveolar lavage (BAL) fluid. METHODS: We performed a single-center observational study with both prospective and retrospective components. The included patients (n = 128) received a planned regimen of indefinite valganciclovir prophylaxis post transplant, regardless of donor (D)/recipient (R) CMV serostatus. Real-time polymerase chain reaction assay for detection of CMV in BAL was prospectively performed over a 1-year period. Clinical data were reviewed retrospectively; median follow-up was 24.8 months (range 1-93 months). RESULTS: Sixty-five patients (50.6%) discontinued valganciclovir prophylaxis, either temporarily or permanently, with a primary cause of mild leukopenia. Six cases of CMV disease were identified (4.7%), with no significant difference between those who were on continuous prophylaxis or not (4.6% vs. 4.9%; P = non-significant [ns]). However, those who discontinued prophylaxis showed an increased incidence of laboratory-detected CMV infection (40.7% vs. 12.7%; P = 0.001). High-risk D+/R- patients did not demonstrate a significantly increased incidence of CMV disease (8.1% vs. 3.3% other serotypes; P = ns). Three patients (2.3%) developed valganciclovir-resistant CMV disease. Molecular detection of CMV in BAL fluid was significantly more sensitive than shell vial culture. However, BAL CMV viral load was not predictive of subsequent disease development. CONCLUSIONS: Extended valganciclovir prophylaxis for all lung transplant recipients led to a low incidence of CMV disease and resistance. In such low-incidence populations, routine quantitation of CMV in BAL did not confer significant clinical benefit over non-quantitative methods in prediction of CMV disease onset.


Assuntos
Antivirais/uso terapêutico , Infecções por Citomegalovirus/prevenção & controle , Citomegalovirus/isolamento & purificação , Ganciclovir/análogos & derivados , Transplante de Pulmão , Adulto , Idoso , Líquido da Lavagem Broncoalveolar/virologia , Citomegalovirus/genética , Infecções por Citomegalovirus/epidemiologia , Infecções por Citomegalovirus/virologia , DNA Viral/análise , Feminino , Ganciclovir/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Valganciclovir , Carga Viral
10.
Plant Biol (Stuttg) ; 24(3): 404-416, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34854195

RESUMO

The GRAS (derived from GAI, RGA and SCR) gene family consists of plant-specific genes, works as a transcriptional regulator and plays a key part in the regulation of plant growth and development. The past decade has witnessed significant progress in understanding and advances on GRAS transcription factors in various plants. A notable concern is to what extent the mechanisms found in plants, particularly crops, are shared by other species, and what other characteristics are dependent on GRAS transcription factor (TFS)-mediated gene expression. GRAS are involved in many processes that are intimately linked to plant growth regulation. However, GRAS also perform additional roles against environmental stresses, allowing plants to function more efficiently. GRAS increase plant growth and development by improving several physiological processes, such as phytohormone, biosynthetic and signalling pathways. Furthermore, the GRAS gene family plays an important role in response to abiotic stresses, e.g. photooxidative stress. Moreover, evidence shows the involvement of GRAS in arbuscule development during plant-mycorrhiza associations. In this review, the diverse roles of GRAS in plant systems are highlighted that could be useful in enhancing crop productivity through genetic modification, especially of crops. This is the first review to report the role and function of the GRAS gene family in plant systems. Furthermore, a large number of studies are reviewed, and several limitations and research gaps identified that must be addressed in future studies.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Família Multigênica , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transdução de Sinais/genética , Estresse Fisiológico/genética , Simbiose/genética
11.
Urban Clim ; 38: 100900, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36570864

RESUMO

The strategies to contain the spread of COVID-19 pandemic, including restricted human movement and economic activities, have shown positive impacts on the environment. Present research analysed the effects of COVID-19 led lockdown on air quality with special reference to major pollutants, namely nitrogen dioxide (NO2), carbon monoxide (CO), sulphur dioxide (SO2) and aerosol optical depth (AOD). The assessment has been conducted for megacities of India (Delhi, Mumbai, Bengaluru, Chennai and Kolkata) for four months, that is, March and April in 2019 and 2020 using Sentinel 5P and MCD19A2 data. A decrease in concentrations of air pollutants, specifically NO2 and SO2, has been observed during the lockdown period in all the cities; whereas CO and AOD have exhibited discrete pattern of spatio-temporal variation. Four megacities except Kolkata have revealed a positive correlation between NO2 concentration and population density. The results conclude overall improvement in air quality during COVID-19 led lockdown. The current situation provides a unique opportunity to implement a structural economic change that could help us move towards a city with low emission economy. Realizing the achievable improvement of air quality, the study suggests further in-depth research on source attribution of individual pollutants to assess the prospect of emission reduction actions.

12.
BioData Min ; 14(1): 21, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33781293

RESUMO

BACKGROUND AND OBJECTIVES: The ideal treatment of illnesses is the interest of every era. Data innovation in medical care has become extremely quick to analyze diverse diseases from the most recent twenty years. In such a finding, past and current information assume an essential job is utilizing and information mining strategies. We are inadequate in diagnosing the enthusiastic mental unsettling influence precisely in the beginning phases. In this manner, the underlying conclusion of misery expressively positions an extraordinary clinical and Scientific research issue. This work is dedicated to tackling the same issue utilizing the AI strategy. Individuals' dependence on passionate stages has been successfully characterized into various gatherings in the data innovation climate. METHODS: A notable AI multi-include cross breed classifier is utilized to execute half and half order by having the passionate incitement as pessimistic or positive individuals. A troupe learning calculation helps to pick the more appropriate highlights from the accessible classes feeling information on online media to improve order. We split the Dataset into preparing and testing sets for the best proactive model. RESULTS: The execution assessment is applied to check the proposed framework through measurements of execution assessment. This exploration is done on the Class Labels MovieLens dataset. The exploratory outcomes show that the used group technique gives ideal order execution by picking the highlights' greatest separation. The supposed results demonstrated the projected framework's distinction, which originates from the picking-related highlights chosen by the incorporated learning calculation. CONCLUSION: The proposed approach is utilized to precisely and successfully analyze the downturn in its beginning phase. It will assist in the recovery and action of discouraged individuals. We presume that the future strategy's utilization is exceptionally appropriate in all data innovation-based E-medical services for discouraging incitement.

13.
Sci Rep ; 11(1): 2896, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33536469

RESUMO

An argon plasma jet was sustained in open air and characterized for its chemical composition. The optically characterized plasma jet was used to treat industrial wastewater containing mixed textile dyes and heavy metals. Since plasma jet produces UV-radiations, the photocatalytic TiO2 was used to enhance plasma treatment efficiency especially for degradation of dyes. Mixed anatase and rutile phases of TiO2 (5.2-8.5 nm) were produced through surfactant assisted sol-gel approach. The emission spectrum confirmed the presence of excited argon, OH, excited nitrogen, excited oxygen, ozone and nitric oxide in the plasma jet. The spectral lines of excited Ar, NO, O3, OH-, N2, [Formula: see text], O, [Formula: see text] and O+ species were observed at wavelength of 695-740 nm, 254.3 nm, 307.9 nm, 302-310 nm, 330-380 nm, 390-415 nm, 715.6 nm, 500-600 nm and 400-500 nm. These reactive species decompose the organic pollutants and separate the heavy metals from the water samples. The conductivity of plasma exposed water samples increased while pH and hardness decreased. The atomic absorption spectrophotometry analysis confirmed the presence of heavy metals in the samples, which were effectively removed through plasma treatment. Finally, the effect of plasma treatment on Staphylococcus aureus strains was more pronounced than Escherichia coli strains.

14.
PLoS One ; 16(10): e0258612, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34634093

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0253464.].

15.
PLoS One ; 16(7): e0253464, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34280209

RESUMO

This study examines the relationship between economic growth, renewable energy consumption, and carbon emissions in Iran between 1975-2017, and the bounds testing approach to cointegration and the asymmetric method was used in this study. The results reveal that in the long run increase in renewable energy consumption and CO2 emissions causes an increase in real GDP per capita. Meanwhile, the decrease in renewable energy has the same effect, but GDP per capita reacts more strongly to the rise in renewable energy than the decline. Besides, in the long run, a reduction of CO2 emissions has an insignificant impact on GDP per capita. Furthermore, the results from asymmetric tests suggest that reducing CO2 emissions and renewable energy consumption do not have an essential role in decreasing growth in the short run. In contrast, an increase in renewable energy consumption and CO2 emissions do contribute to boosting the growth. These results may be attributable to the less renewable energy in the energy portfolio of Iran. Additionally, the coefficients on capital and labor are statistically significant, and we discuss the economic implications of the results and propose specific policy recommendations.

16.
Indian J Lepr ; 82(3): 123-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21449223

RESUMO

Leprosy, a chronic infectious disease, caused by Mycobacterium leprae infection, manifests itself as a clinical spectrum depending on the patients' immunological response, finally leading to peripheral nerve damage and deformities in the patients. Nitric oxide (NO) which is known to contribute to pathogenesis of several neurological diseases has been detected in tissues and urine of leprosy patients. This is the first study assessing NO as its stable end products, nitrites and nitrates, in sera of patients across the spectrum of the disease as a possible parameter of prognostic value. Comparison of NO metabolites showed a significant increase in multibacillary patients and patients with type I reactions as compared to healthy control individuals. These levels reduced significantly after treatment. This study has further borne out the utility and reliability of the cadmium-reduction method of estimation of NO metabolites--a relatively inexpensive procedure that lends itself to large-scale screening and follow-up of patients.


Assuntos
Cádmio , Hanseníase/sangue , Nitratos/sangue , Óxido Nítrico/metabolismo , Nitritos/sangue , Adulto , Cádmio/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Índia , Cinética , Hansenostáticos/uso terapêutico , Hanseníase/classificação , Hanseníase/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/sangue , Prognóstico , Soro/química , Adulto Jovem
17.
East Mediterr Health J ; 16 Suppl: S24-30, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21495585

RESUMO

Smokeless tobacco (ST), widely used in Pakistan, poses a high risk for oral cancer. Our hospital-based data illustrate that oropharyngeal cancer (9.9%) is the second leading malignancy after breast cancer (16.1%), and is significantly higher than in other Member States of the World Health Organization's Eastern Mediterranean Region. Urdu-speaking communities had a proportionately higher rate of oropharyngeal cancer (20.4%), followed by Balochis (19.9%), Sindhis (16.8%), Punjabis (11.7%) and Pashtuns (9.6%). Association of oropharyngeal cancer with ST use was four times higher relative to no history of tobacco use after adjustingfor age, ethnicity and gender. Our findings also show a predominance of this cancer among males relative to females and one-third of the reported cases occurred among individuals under 40 years. These findings have significant social impact, indicating the need for urgent intervention against the use of ST.


Assuntos
Neoplasias Orofaríngeas/etiologia , Tabaco sem Fumaça/efeitos adversos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Neoplasias/epidemiologia , Neoplasias Orofaríngeas/epidemiologia , Paquistão/epidemiologia , Adulto Jovem
18.
Int J Disaster Risk Reduct ; 50: 101681, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32834974

RESUMO

Strong communication systems for knowledge exchange are required to prevent, respond to and mitigate the effects of emerging public health incidents (EPHIs). The objective of this paper is to examine how "tacit knowledge" - implicit knowledge used to guide everyday practice - is employed in professional relationships and communication processes between public health and acute care settings. A qualitative study design was used to explore the experiences of key informants from public health and acute care settings in Ontario, Canada, to examine how specific dimensions of tacit knowledge are employed in communications about EPHIs. Twenty-six in-depth interviews were conducted from 2014 to 2015. The results describe the way in which participants employ discretion and knowledge of local context, and rely on relationships built on trust and credibility, to facilitate decision-making and communication during EPHIs. Given the uncertainty characterizing most EPHIs, communicators rely a great deal on their informal knowledge and networks which allow them to remain flexible and respond quickly to changing situations. The results reveal that communication about public health guidance during emergencies is a complex and active process that draws from past experiences of the individuals involved, and is shaped by the requirements of local circumstances. The broader implications of these findings for building resilient and responsive health systems are considered. In particular, for rethinking the authority of standardized forms of evidence in public health decision-making, and the importance of knowledge which is grounded in the uniqueness of specific local contexts.

19.
Comput Methods Programs Biomed ; 197: 105704, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32889405

RESUMO

OBJECTIVE AND BACKGROUND: The current scenario of the Pandemic of COVID-19 demands multi-channel investigations and predictions. A variety of prediction models are available in the literature. The majority of these models are based on extrapolating by the parameters related to the diseases, which are history-oriented. Instead, the current research is designed to predict the mortality rate of COVID-19 by Regression techniques in comparison to the models followed by five countries. METHODS: The Regression method with an optimized hyper-parameter is used to develop these models under training data by Machine Learning Technique. RESULTS: The validity of the proposed model is endorsed by considering the case study on the data for Pakistan. Five distinct models for mortality rate prediction are built using Confirmed cases data as a predictor variable for France, Spain, Turkey, Sweden, and Pakistan, respectively. The results evidenced that Sweden has a fewer death case over 20,000 confirmed cases without observing lockdown. Hence, by following the strategy adopted by Sweden, the chosen entity will control the death rate despite the increase of the confirmed cases. CONCLUSION: The evaluated results notice the high mortality rate and low RMSE for Pakistan by the GPR method based Mortality model. Therefore, the morality rate based MRP model is selected for the COVID-19 death rate in Pakistan. Hence, the best-fit is the Sweden model to control the mortality rate.


Assuntos
COVID-19/mortalidade , Aprendizado de Máquina , Pandemias , COVID-19/epidemiologia , COVID-19/prevenção & controle , Biologia Computacional , Humanos , Modelos Biológicos , Modelos Estatísticos , Dinâmica não Linear , Distribuição Normal , Pandemias/prevenção & controle , Pandemias/estatística & dados numéricos , Análise de Regressão , Estatísticas não Paramétricas , Suécia/epidemiologia
20.
Sci Rep ; 10(1): 15548, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32968140

RESUMO

This study examines the analytical and numerical solution of electromagnetic surface waves supported by a resistive metasurface-covered grounded metamaterial structure. To simulate the metamaterial, the Kramers-Kronig relation based on the causality principle is used, while the modeling of the resistive metasurface has been done by implementing the impedance boundary conditions. The analytical expressions for the field phasors of surface waves are developed for the transverse magnetic (TM) polarized mode and transverse electric (TE) polarized mode. The characteristic equations are computed for both modes, and the unknown propagation constant is evaluated numerically in the kernel. After computation, the dispersion curves, electric field profiles, effective mode index ([Formula: see text]), and phase speeds ([Formula: see text]) are presented for both the TM and TE polarized modes. To study the tunability of surface waves, the influence of the thickness of the metamaterial slab ([Formula: see text]), effective permittivity of the metamaterial ([Formula: see text]), thickness of the resistive metasurface ([Formula: see text]), and effective permittivity of the metasurface ([Formula: see text]) on all the numerical results has been studied. However, the geometrical parameters are found to be more sensitive to the effective mode index ([Formula: see text]) and phase speed ([Formula: see text]) of the surface waves. The results are consistent with the published results, which reflects the accuracy of the work. It is concluded that the appropriate choice of parameters can be used to achieve surface waves with the desired characteristics in the GHz range. The present work may have potential applications in surface waveguide design, surface wave speed controllers, surface communication devices, and light trapping configurations.

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