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1.
ACS Appl Mater Interfaces ; 16(17): 21799-21806, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38635921

RESUMO

Because of their high theoretical energy density, metal-CO2 batteries based on Li, Na, or K have attracted increasing attention recently for meeting the growing demands of CO2 recycling and conversion into electrical energy. However, the scarcity of active anode material resources, high cost, as well as safety concerns of Li, Na, and K create obstacles for practical applications. Herein, we demonstrate for the first time a high-efficiency (η = 77.2%) rechargeable Fe-CO2 battery that is composed of iron (Fe) anode and MoS2-catalysts deposited carbon cathode. MoS2 catalysts are crucial to the successful acceleration of reaction kinetics of Fe during charge and discharge with a minimum overpotential of the cell. The Fe-CO2 cell has a higher initial specific capacity of 12,500 mA h g-1 with an average discharge potential of 0.65 V and operates reversibly with a lower overpotential than that of Li-CO2 batteries with a cutoff capacity of 500 mA h g-1. Our Fe-CO2 battery can effectively convert CO2 greenhouse gas into electrical energy by consuming 1 ton of CO2 with usage of 1.23 tons of iron.

2.
JNMA J Nepal Med Assoc ; 61(268): 938-940, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38289757

RESUMO

Introduction: Overweight is defined as a condition in which abnormal accumulation of fat directly affects an individual personality and health leading to a marked increase in morbidity and mortality. It has a direct impact on both the psychological aspects of an individual's personality and their overall health. The objective of this study was to find out the prevalence of overweight among medical students in a medical college. Methods: A descriptive cross-sectional study was done among first and second-year medical students in a medical college between 20 February 2023 to 3 March 2023 after receiving ethical approval from the Institutional Review Committee. Students studying Bachelor of Medicine, Bachelor of Surgery and Bachelor of Dental Surgery during the study period who gave consent were included and those students with a recent medical history of fever, typhoid, diarrhoea, thyroid disorder, metabolic disorders, or any other relevant medical condition within the preceding 1 month, potentially influencing body weight, were excluded. A convenience sampling method was used. The point estimate was calculated at a 95% Confidence Interval. Results: Among 164 students, the prevalence of overweight was 43 (26.22%) (19.49-32.95, 95% Confidence Interval). The mean age was 20.65±1.08 years. Conclusions: The prevalence of overweight among medical students was higher than in other studies done in similar settings. Keywords: anthropometry; body mass index; body weight; overweight.


Assuntos
Sobrepeso , Estudantes de Medicina , Humanos , Adulto Jovem , Adulto , Sobrepeso/epidemiologia , Estudantes de Medicina/psicologia , Obesidade/epidemiologia , Estudos Transversais , Peso Corporal
3.
BMC Bioinformatics ; 13: 190, 2012 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-22856879

RESUMO

BACKGROUND: Web-based synteny visualization tools are important for sharing data and revealing patterns of complicated genome conservation and rearrangements. Such tools should allow biologists to upload genomic data for their own analysis. This requirement is critical because individual biologists are generating large amounts of genomic sequences that quickly overwhelm any centralized web resources to collect and display all those data. Recently, we published a web-based synteny viewer, GSV, which was designed to satisfy the above requirement. However, GSV can only compare two genomes at a given time. Extending the functionality of GSV to visualize multiple genomes is important to meet the increasing demand of the research community. RESULTS: We have developed a multi-Genome Synteny Viewer (mGSV). Similar to GSV, mGSV is a web-based tool that allows users to upload their own genomic data files for visualization. Multiple genomes can be presented in a single integrated view with an enhanced user interface. Users can navigate through all the selected genomes in either pairwise or multiple viewing mode to examine conserved genomic regions as well as the accompanying genome annotations. Besides serving users who manually interact with the web server, mGSV also provides Web Services for machine-to-machine communication to accept data sent by other remote resources. The entire mGSV package can also be downloaded for easy local installation. CONCLUSIONS: mGSV significantly enhances the original functionalities of GSV. A web server hosting mGSV is provided at http://cas-bioinfo.cas.unt.edu/mgsv.


Assuntos
Genômica/métodos , Internet , Software , Sintenia , Biologia Computacional/métodos , Interface Usuário-Computador
4.
JNMA J Nepal Med Assoc ; 60(250): 584-587, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35690972

RESUMO

Medicine is a line of work in which expectations run high, having a competitive spirit is considered a virtue and relentless hard work is deemed a reward in itself. Yet, in a strenuous environment such as this, communication about the struggles medical students face is found to be almost non-existent. This leads to medical students feeling burnt out, lost and inadequate, bringing about a drop in performance quality and/or quantity, which breeds further insecurity. This acts as a vicious cycle that is further perpetuated by the lack of effective communication, which becomes a bedrock for the deficit in support from peer groups, educators and authorities. There are different theories of motivation and these form the basis for exploring the different ways in which it can be increased. These methods, which contribute to enhancing productivity and curtailing stress, are detailed in the article. Keywords: cognition; medical students; motivation; self-concept.


Assuntos
Faculdades de Medicina , Estudantes de Medicina , Cognição , Humanos , Motivação , Autoimagem
5.
JNMA J Nepal Med Assoc ; 60(255): 978-981, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36705174

RESUMO

Lissencephaly is a malformation of cortical development associated with deficient neuronal migration and abnormal formation of cerebral convolutions or gyri. The lissencephaly spectrum consists of agyria, pachygyria, and subcortical band heterotopia. At least 19 genes have been identified in the causation of lissencephaly and related syndrome. Lissencephaly is associated with many other congenital disorders but the association of lissencephaly with congenital hypothyroidism is rarely reported. We report a case of a 10-year-old girl having lissencephaly with congenital hypothyroidism. Early diagnosis of lissencephaly and genetic counselling can be made in suspected cases and further possible interventions can be taken. Also, regular follow-up, monitoring, and better conservative management lead to a better prognosis. Keywords: congenital abnormalities; hypothyroidism; lissencephaly; neuronal migration disorders.


Assuntos
Lissencefalias Clássicas e Heterotopias Subcorticais em Banda , Hipotireoidismo Congênito , Lisencefalia , Feminino , Humanos , Criança , Hipotireoidismo Congênito/complicações , Hipotireoidismo Congênito/diagnóstico , Lisencefalia/complicações , Lisencefalia/diagnóstico , Lisencefalia/genética , Lissencefalias Clássicas e Heterotopias Subcorticais em Banda/diagnóstico , Lissencefalias Clássicas e Heterotopias Subcorticais em Banda/genética , Fenótipo
6.
Carbohydr Polym ; 293: 119731, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35798427

RESUMO

This study demonstrates flexible, ultra-high rate, and long cycle life lithium­sulfur batteries using bacterial cellulose (BC) derived cathode host as well as separator. The work also includes a new strategy to use active sulfur in the form of catholyte added directly to the electrolyte for improved sulfur utilization. The fabricated LiS cell with carbonized bacterial cellulose (CBC) as a cathode host and BC as a separator (CBC@BC) delivers an impressive capacity of 740 mAh g-1 at 1C. It retains a capacity of 310 mAh g-1 even at an ultra-high rate of 4C. To have commercial adoption of CBC@BC, we tested LiS cells with a high areal loading of 5 mg cm-2. The cell shows promising electrochemical performance for 500 cycles with a capacity retention of 82 %. Furthermore, first-principle calculations are performed to understand the interaction of soluble lithium-polysulfides with bacterial cellulose-derived material.


Assuntos
Celulose , Lítio , Fontes de Energia Elétrica , Eletrodos , Enxofre
7.
Small Methods ; 6(12): e2200930, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36333232

RESUMO

In recent times, the Li-CO2 battery has gained significant importance arising from its higher gravimetric energy density (1876 Wh kg-1 ) compared to the conventional Li-ion batteries. Also, its ability to utilize the greenhouse gas CO2 to operate an energy storage system and the prospective utilization on extraterrestrial planets such as Mars motivate to practicalize it. However, it suffers from numerous challenges such as (i) the reluctant CO2 reduction/evolution; (ii) solid/liquid/gas interface blockage arising from the deposition of Li2 CO3 discharge product on the cathode; (iii) high overpotential to decompose the stable discharge product Li2 CO3 ; and (iv) instability of the electrolytes. Numerous efforts have been undertaken to tackle these challenges by developing catalysts, improving the stability of electrolytes, protecting the anode, etc. Despite these efforts, due to the lack of a decisive confirmation of the reaction mechanisms of the discharging/charging reactions occurring in the system, the progress of the Li-CO2 battery system has been slow. In situ characterization techniques help overcome ex-situ techniques' limitations by monitoring the processes with the progress of a reaction. The current review focuses on bridging the gap in the understanding of the Li-CO2 batteries by exploring the various in situ/operando characterization techniques that have been employed.

8.
Indian J Pediatr ; 87(10): 840-845, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32281058

RESUMO

Congenital infections affecting newborn infants can have potentially devastating clinical outcomes. They are usually caused by viruses that infect mothers during pregnancy and are transmitted to the fetus or newborn during the prenatal, perinatal or postnatal periods. Congenital cytomegalovirus (cCMV) is the most common congenital infection affecting up to 2.5% of all live births. Even though most infected infants are asymptomatic at birth, cCMV is an important cause of neurodevelopmental impairment and represents the main cause of non-hereditary sensorineural hearing loss. Also, congenital Zika infection has emerged in recent years as a cause of microcephaly and neurodevelopmental delays. Currently, universal screening is not recommended for either infection in pregnant women or newborn infants. Therefore, screening for both conditions is based on multiple factors such as maternal immune status, exposure, and clinical manifestations of the infant. Use of antiviral medications on symptomatic cCMV has shown improvement in outcomes, in contrast with congenital Zika for which there are no therapeutic options available. Even though both viruses can be present in breast milk, there are no recommendations against breastfeeding in full-term infants. Close follow-up for affected infants is necessary to monitor for developmental delays and sensory impairments to implement interventional therapies at the earliest time possible.


Assuntos
Infecções por Citomegalovirus , Doenças Fetais , Complicações Infecciosas na Gravidez , Infecção por Zika virus , Zika virus , Citomegalovirus , Infecções por Citomegalovirus/diagnóstico , Feminino , Humanos , Lactente , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Infecção por Zika virus/complicações , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/epidemiologia
9.
ACS Omega ; 5(27): 16681-16689, 2020 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32685835

RESUMO

Our society is critically dependent on lithium-ion batteries (LIBs) as a power source for portable electronic gadgets. One of the major problems with these batteries is the degradation of the materials inside them. In addition to the reduced cell life, building-up of these degraded products inside the cells is very detrimental to the safe operation. Herein, we report the synthesis and characterization of a novel thiourea-based room temperature ionic liquid (IL), 3-heptyl-1-(3-(3-heptyl-3-phenylthioureido)propyl)-1H-imidazole-3-ium hexafluorophosphate. Its electrochemical and thermal properties including transport phenomena have been studied. It is proposed to be used as a nominal additive to commercially used electrolytes, ethylene carbonate and di-methyl carbonate mixtures. The comparative performance characteristics of the LIBs in the presence and the absence of this IL additive have been demonstrated with a traditional lithium nickel cobalt manganese oxide cathode (NMC111), a graphite anode, and an ethylene carbonate and di-methyl carbonate (1:1, v/v) electrolyte. It is further demonstrated that use of this electrolyte additive in batteries helps to address some of the major concerns of the conventional electrolytes such as safety issues and cycling performance as well as coulombic efficiency with enhanced discharge capacities.

10.
Sci Rep ; 10(1): 9606, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32541876

RESUMO

A novel dicationic room temperature ionic liquid, 1,1'-(5,14-dioxo-4,6,13,15-tetraazaoctadecane-1,18-diyl) bis(3-(sec-butyl)-1H-imidazol-3-ium) bis((trifluoromethyl)-sulfonyl) imide has been synthesized and fully characterized. Its thermal and electrochemical analyses along with transport properties have been studied. We propose it as a potential nominal additive to the commonly used conventional organic carbonate electrolyte mixture and study its adaptability in Lithium-ion batteries which are the prime power sources for ultraportable electronic devices. We have compared the performance characteristics of the full cells made without and with this ionic liquid. The cells comprise lithium nickel cobalt manganese oxide cathode, graphite anode and ethylene carbonate - dimethyl carbonate (1:1, v/v + LiPF6) mixture electrolyte with nominal amount of ionic liquid as additive. The major concern with conventional electrolytes such as degradation of the materials inside batteries has been addressed by this electrolyte additive. Additionally, this additive is safer at relatively higher temperature. In its presence, the overall battery life is enhanced and it shows good cycling performance and coulombic efficiency with better discharge capacities (22% higher) after 100 cycles. Even after the increase in current rate from 10 mA/g to 100 mA/g, the cell still retains around 73% of capacity.

11.
J Infect ; 67(5): 399-407, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23867867

RESUMO

OBJECTIVES: Indian contribution to global burden of tuberculosis is about 26%. In the present study we have developed an in-house PCR assay using primers for sdaA gene of Mycobacterium tuberculosis and evaluated against already established primers devR, IS6110, MPB64, rpoB primers for diagnosis of pulmonary tuberculosis. METHODS: Using universal sample preparation (USP) method, DNA was extracted from sputum specimens of 412 symptomatic patients from Delhi, India. The DNA so extracted was used as template for PCR amplification using primers targeting sdaA, devR, IS6110, MPB64 and rpoB genes. RESULTS: Out of 412, 149 specimens were considered positive based on composite reference standard (CRS) criteria. The in-house designed sdaA PCR showed high specificity (96.5%), the high positive likelihood ratio (28), the high sensitivity (95.9%), and the very low negative likelihood ratio (0.04) in comparison to CRS. CONCLUSION: Based on our results, the sdaA PCR assay can be considered as one of the most reliable diagnostic tests in comparison to other PCR based detection methods.


Assuntos
Mycobacterium tuberculosis/genética , Reação em Cadeia da Polimerase/métodos , Tuberculose Pulmonar/microbiologia , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Proteínas de Bactérias/genética , DNA Bacteriano/análise , DNA Bacteriano/genética , Monitoramento de Medicamentos , Humanos , Índia , Tipagem Molecular/métodos , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Sensibilidade e Especificidade , Escarro/microbiologia , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/tratamento farmacológico
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