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1.
Int J Appl Basic Med Res ; 13(1): 10-15, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37266522

RESUMO

Context: Laparoscopic cholecystectomy (LC) is established as the gold standard for benign gallbladder disease. This study was done for the evaluation of preoperative scoring system given by Randhawa and Pujahari considering various preoperative parameters to predict difficulty in LC. Aims: Preoperative prediction of difficult LC using a scoring system considering various preoperative factors in elective/interval LC to predict difficult gallbladder. Settings and Design: A prospective study of 120 patients admitted for LC from January 2020 to June 2021 was analyzed. Subjects and Methods: All the patients were evaluated on the basis of Randhawa and Pujahari scoring system with the following variables: age >50 years, male sex, body mass index 25.1-27.5 and >27.5 kg/m2, previous abdominal surgery, prior hospitalization for gallstone disease, palpable gallbladder, gallbladder wall thickening, impacted stone, and pericholecystic collection. Each variable had given a score. Based on these findings, the surgical procedure was defined as easy, difficult, and very difficult. Results: One hundred and twenty cases satisfying the inclusion criteria were studied comparing different variables and assigned preoperative scoring. A score >5 was considered significant and compared with intraoperative findings. Out of 53 patients having preoperative scores >5, 40 were difficult gallbladders and 13 were easy to operate. Prediction came true in 93.0% of difficult cases and 83.1% of easy cases. Conclusions: From this study, we can conclude that the preoperative scoring system is statistically reliable to predict difficulty in LC in the majority of the cases (area under receiver operator characteristics = 0.935).

2.
Genes Brain Behav ; 22(1): e12836, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36636829

RESUMO

The blood brain barrier (BBB) has the essential function to protect the brain from potentially hazardous molecules while also enabling controlled selective uptake. How these processes and signaling inside BBB cells control neuronal function is an intense area of interest. Signaling in the adult Drosophila BBB is required for normal male courtship behavior and relies on male-specific molecules in the BBB. Here we show that the dopamine receptor D2R is expressed in the BBB and is required in mature males for normal mating behavior. Conditional adult male knockdown of D2R in BBB cells causes courtship defects. The courtship defects observed in genetic D2R mutants can be rescued by expression of normal D2R specifically in the BBB of adult males. Drosophila BBB cells are glial cells. Our findings thus identify a specific glial function for the DR2 receptor and dopamine signaling in the regulation of a complex behavior.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Masculino , Drosophila/fisiologia , Barreira Hematoencefálica/metabolismo , Dopamina/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Corte , Drosophila melanogaster/genética , Comportamento Sexual Animal/fisiologia
3.
Sensors (Basel) ; 22(14)2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35891062

RESUMO

The search for a highly portable and efficient supply of energy to run small-scale wireless gadgets has captivated the human race for the past few years. As a part of this quest, the idea of realizing a Quantum battery (QB) seems promising. Like any other practically tractable system, the design of QBs also involve several critical challenges. The main problem in this context is to ensure a lossless environment pertaining to the closed-system design of the QB, which is extremely difficult to realize in practice. Herein, we model and optimize various aspects of a Radio-Frequency (RF) Energy Harvesting (EH)-assisted, QB-enabled Internet-of-Things (IoT) system. Several RF-EH modules (in the form of micro- or nano-meter-sized integrated circuits (ICs)) are placed in parallel at the IoT receiver device, and the overall correspondingly harvested energy helps the involved Quantum sources achieve the so-called quasi-stable state. Concretely, the Quantum sources absorb the energy of photons that are emitted by a photon-emitting device controlled by a micro-controller, which also manages the overall harvested energy from the RF-EH ICs. To investigate the considered framework, we first minimize the total transmit power under the constraints on overall harvested energy and the number of RF-EH ICs at the QB-enabled wireless IoT device. Next, we optimize the number of RF-EH ICs, subject to the constraints on total transmit power and overall harvested energy. Correspondingly, we obtain suitable analytical solutions to the above-mentioned problems, respectively, and also cross-validate them using a non-linear program solver. The effectiveness of the proposed technique is reported in the form of numerical results, which are both theoretical and simulations based, by taking a range of operating system parameters into account.

4.
Sensors (Basel) ; 21(18)2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34577217

RESUMO

In order to support a massive number of resource-constrained Internet-of-Things (IoT) devices and machine-type devices, it is crucial to design a future beyond 5G/6G wireless networks in an energy-efficient manner while incorporating suitable network coverage expansion methodologies. To this end, this paper proposes a novel two-hop hybrid active-and-passive relaying scheme to facilitate simultaneous wireless information and power transfer (SWIPT) considering both time-switching (TS) and power-splitting (PS) receiver architectures, while dynamically modelling the involved dual-hop time-period (TP) metric. An optimization problem is formulated to jointly optimize the throughput, harvested energy, and transmit power of a SWIPT-enabled system with the proposed hybrid scheme. In this regard, we provide two distinct ways to obtain suitable solutions based on the Lagrange dual technique and Dinkelbach method assisted convex programming, respectively, where both the approaches yield an appreciable solution within polynomial computational time. The experimental results are obtained by directly solving the primal problem using a non-linear optimizer. Our numerical results in terms of weighted utility function show the superior performance of the proposed hybrid scheme over passive repeater-only and active relay-only schemes, while also depicting their individual performance benefits over the corresponding benchmark SWIPT systems with the fixed-TP.


Assuntos
Algoritmos , Rede Social , Internet
5.
BMJ Open ; 7(3): e015036, 2017 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-28314746

RESUMO

INTRODUCTION: Diarrhoea is a leading cause of death globally, mostly occurring as a result of insufficient or unsafe water supplies, inadequate sanitation and poor hygiene. Our study aims to investigate the impact of a community-level hygiene education program and a water quality intervention using riverbank filtration (RBF) technology on diarrhoeal prevalence. METHODS AND ANALYSIS: We have designed a stepped wedge cluster randomised trial to estimate the health impacts of our intervention in 4 rural villages in Karnataka, India. At baseline, surveys will be conducted in all villages, and householders will receive hygiene education. New pipelines, water storage tanks and taps will then be installed at accessible locations in each village and untreated piped river water will be supplied. A subsequent survey will evaluate the impact of hygiene education combined with improved access to greater water volumes for hygiene and drinking purposes (improved water quantity). Villages will then be randomly ordered and RBF-treated water (improved water quality) will be sequentially introduced into the 4 villages in a stepwise manner, with administration of surveys at each time point. The primary outcome is a 7-day period prevalence of self-reported diarrhoea. Secondary outcomes include self-reported respiratory and skin infections, and reported changes in hygiene practices, household water usage and water supply preference. River, tank and tap water from each village, and stored water from a subset of households, will be sampled to assess microbial and chemical quality. ETHICS AND DISSEMINATION: Ethics approval was obtained from the Monash University Human Research Ethics Committee in Australia and The Energy and Resources Institute Institutional Ethics Committee in India. The results of the trial will be presented at conferences, published in peer-reviewed journals and disseminated to relevant stakeholders. This study is funded by an Australian National Health and Medical Research Council (NHMRC) project grant. TRIAL REGISTRATION NUMBER: ACTRN12616001286437; pre-results.


Assuntos
Diarreia/prevenção & controle , Filtração , Educação em Saúde , Higiene , Engenharia Sanitária , Qualidade da Água , Abastecimento de Água , Água Potável , Características da Família , Humanos , Índia , Prevalência , Características de Residência , Rios , População Rural , Inquéritos e Questionários , Tecnologia , Água
6.
Environ Technol ; 33(7-9): 943-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22720419

RESUMO

The fact that ozone is a very powerful oxidizing agent (E0 = +2.07 V) was harnessed to degrade endosulfan and lindane in the present study. An ozone dosage of 57 mg min(-1) was found to be optimal for the degradation of both endosulfan (89%) and lindane (43%). The pH of the reaction mixtures play a profound role on the extent of degradation and it was observed that alkaline conditions favours the generation of hydroxyl radicals and thus a pH of 10 was chosen as the optimum for endosulfan degradation as the degradation efficiency was found to be 93%. A pH value of 12 was chosen as the optimum for lindane degradation as the degradation efficiency was observed to be 82%. Kinetics of degradation was performed and the set of data was fitted into first-order kinetics of the reaction for both endosulfan and lindane. The observed rate constants (k(obs')) for 5, 7.5 and 10 ppm initial endosulfan concentrations were 0.0274, 0.0273 and 0.0161 min(-1), respectively. While for initial lindane concentrations of 5, 7.5 and 10 ppm, the observed rate constants were 0.0243, 0.0333 and 0.056 min(-1), respectively. Gas chromatography mass spectroscopy analysis revealed that endosulfan was degraded into methyl cyclohexane and o-xylene which disappeared as reaction proceeded and lindane was degraded to 1-hexene indicating the ring fission mechanism.


Assuntos
Endossulfano/química , Hexaclorocicloexano/química , Inseticidas/química , Ozônio/química , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Cinética
7.
Water Environ Res ; 83(9): 865-73, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22073734

RESUMO

A Mg0/Pd(+4) bimetallic system was evaluated to dechlorinate endosulfan and lindane in the aqueous phase. Studies were conducted with endosulfan and lindane separately, with or without acid in a 1:1 (v/v) water:acetone phase. In the absence of any acid, higher degradation of endosulfan and lindane was observed using Mg0/Pd(+4) doses of 10/0.5 and 4/0.1 mg/mL, respectively. Acetone plays an important role in facilitating the dechlorination reaction by increasing the solubilities of pesticides. Dechlorination kinetics for endosulfan and lindane (30 and 50 mg/L [30 and 50 ppm] concentration of each pesticide) were conducted with varying Mg0/Pd(+4) doses, and the time-course profiles were well-fitted into exponential curves. The optimum observed rate constants (k(obs)) for endosulfan and lindane were obtained with Mg0/Pd(+4) doses of 5/0.5 and 4/0.1 mg/mL, respectively. Gas chromatography-mass spectrometry analyses revealed that endosulfan and lindane were dechlorinated completely into their hydrocarbon skeletons-Bicyclo [2,2,1] hepta 2-5 diene and benzene, respectively.


Assuntos
Cloro/química , Endossulfano/química , Hexaclorocicloexano/química , Manganês/química , Paládio/química , Praguicidas/química , Cromatografia Gasosa-Espectrometria de Massas
8.
Water Res ; 45(7): 2383-91, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21353283

RESUMO

In the present study, Mg 0/ZnCl 2 bimetallic system was evaluated for its efficiency to dechlorinate endosulfan and lindane in aqueous phase. Presence of acetone in the reaction mixture played an important role by increasing the solubilities of both pesticides and thereby accelerating its mass transfer. Water acetone ratio of 2:1 and 1:1 (v/v) was found optimum for the dechlorination of endosulfan and lindane respectively. Presence of H+ ions in the reaction mixture (50 µl ml(-1) of glacial acetic acid) accelerated the degradation efficiency of 30 ppm initial concentration of endosulfan (96% removal) and lindane (98% removal) at Mg 0/ZnCl 2 dose of 5/1 mg ml(-1) within 30 min of reaction. Dechlorination kinetics for endosulfan and lindane (10, 30 and 50 ppm initial concentration of each pesticide) with varying Mg 0/ZnCl 2 doses and the time course profiles of each pesticide were well fitted into the first order dechlorination reaction. The optimum observed rate constant (k(obs)') values for endosulfan (0.2168, 0.1209 and 0.1614 min(-1) for 10, 30 and 50 ppm initial concentration respectively) and lindane (0.1746, 0.1968 and 0.2253 min(-1) for 10, 30 and 50 ppm initial concentration respectively) dechlorination were obtained when the reactions were conducted with doses of 7.5/1 mg ml(-1) and 5/1 mg ml(-1) Mg 0/ZnCl 2 respectively. Endosulfan and lindane were completely dechlorinated into their hydrocarbon skeletons namely, Bicyclo [2,2,1] hepta 2-5 diene and Benzene respectively as revealed by GCMS analysis.


Assuntos
Cloretos/química , Disruptores Endócrinos/química , Endossulfano/química , Hexaclorocicloexano/química , Magnésio/química , Compostos de Zinco/química , Acetona/química , Poluentes Ambientais/química , Recuperação e Remediação Ambiental/métodos , Halogenação , Cinética
9.
Water Environ Res ; 79(4): 430-5, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17489278

RESUMO

Kinetic studies on the dechlorination of 1,1-dichloro-2,2 bis (4,-chlorophenyl) ethane (DDD) and 1,1,dichloro-2,2 bis (4,-chlorophenyl) ethylene (DDE) in 0.05% biosurfactant revealed that the reaction follows second-order kinetics. The rate of reaction was dependent on the presence of acid, initial concentrations of the target compound, and zerovalent magnesium/tetravalent palladium. Gas chromatography-mass spectrometry analyses of DDE dechlorination revealed the formation of a completely dechlorinated hydrocarbon skeleton, with diphenylethane as the end product, thereby implying the removal of all four chlorine atoms of DDE. In the case of DDD, we identified two partially dechlorinated intermediates [namely, 1,1-dichloro-2, 2 bis (phenyl) ethane and 1, chloro-2, 2 bis (phenyl) ethane] and diphenylethane as the end product. On the basis of products formed from DDD dehalogenation, we propose the removal of aryl chlorine atoms as a first step. Our investigation reveals that biosurfactant may be an attractive solubilizing agent for DDT and its residues. The magnesium/palladium system is a promising option because of its high reactivity and ability to achieve complete dechlorination of DDE and DDD.


Assuntos
Diclorodifenil Dicloroetileno/química , Diclorodifenildicloroetano/química , Inseticidas/química , Magnésio/química , Paládio/química , Diclorodifenil Dicloroetileno/isolamento & purificação , Diclorodifenildicloroetano/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Inseticidas/isolamento & purificação , Cinética , Propriedades de Superfície , Fatores de Tempo
10.
J Hazard Mater ; 139(1): 146-53, 2007 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-16846688

RESUMO

The aim of our investigation was to compare the rates of dechlorination of DDT using Mg0/Pd4+ system in two different reaction phases, namely, water-acetone and 0.05% biosurfactant in water. Since palladium is expensive and its toxicity effects are not well known we also examined the reuse efficiency of Pd0 immobilized on alumina for dechlorinating DDT. Studies on the dechlorination of DDT in water-acetone (1:1, v/v) and 0.05% biosurfactant phases revealed that the reaction followed second order kinetics and rate of reaction is dependent upon both initial concentrations of the target compound and Mg0/Pd4+. The presence of acid enhanced the rate of reaction by providing protons and preventing passivation of metal that occurs due to deposition of magnesium hydroxide. GC-MS analyses revealed the formation of completely dechlorinated hydrocarbon skeleton of DDT namely, diphenylethane (DPE), as the end product in both reaction phases (water-acetone and 0.05% biosurfactant in water) thereby implying the removal of all five chlorine atoms (three alkyl and two aryl) of DDT. The optimum ratio of water and acetone to facilitate successful dechlorination reaction was found to be 9:1. Results suggested that salt form (K2PdCl6) of palladium had higher potential to dechlorinate DDT as compared to pellet (Pd0-alumina) form (efficiencies of 95 and 36%, respectively, for 100 ppm initial concentration of DDT). We noted that Pd0-alumina pellets could be reused at least four times for successful dechlorination of DDT provided Mg0 granules are present in sufficient quantity. Technical grade DDT (50 ppm) containing significant amounts of DDD was dechlorinated almost completely by the Mg0/Pd4+ (10mg/0.2mg/ml) within 1h in water-biosurfactant phase. Our studies reveal that Mg/Pd system is a promising option due to its high reactivity and its ability to achieve complete dechlorination of DDT. This bimetallic system may be useful for designing indigenous permeable barriers or reactors for the treatment of DDT contaminated water.


Assuntos
Cloro/isolamento & purificação , DDT/química , Magnésio/química , Paládio/química , Acetona , Ácidos , Óxido de Alumínio , Compostos Benzidrílicos/análise , Compostos Benzidrílicos/química , Cromatografia Gasosa , Conservação dos Recursos Naturais , DDT/análise , Cinética , Espectrometria de Massas , Sais , Soluções , Tensoativos/metabolismo
11.
J Colloid Interface Sci ; 304(1): 144-51, 2006 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-16996073

RESUMO

Mg0/Pd4+ was able to dechlorinate >99% of extractable DDT (initial concentration of 10 mg DDT kg(-1) of soil) and >90% of extractable DDT (initial concentration of 50 mg DDT kg(-1) of soil) in soil slurry. Mg0/Pd4+ was also found to be effective in dechlorinating of 50 mg kg(-1) DDD and DDE, in soil aged for varying time periods. GC-MS analyses revealed the formation of 1,1-diphenylethane as an end product from DDT, DDE and DDD. To the best of our knowledge this is the first report describing the application Mg0/Pd4+ system for remediation of DDT, DDD and DDE contaminated soil. We conclude that reductive dechlorination reaction catalyzed by Mg0/Pd4+ may be a promising system to remediate soil contaminated with DDT and its dechlorinated products such as DDD and DDE.


Assuntos
DDT/química , Diclorodifenil Dicloroetileno/química , Diclorodifenildicloroetano/química , Magnésio/química , Paládio/química , Poluentes do Solo/química , Adsorção , Compostos Benzidrílicos/análise , Compostos Benzidrílicos/síntese química , DDT/isolamento & purificação , Diclorodifenil Dicloroetileno/isolamento & purificação , Diclorodifenildicloroetano/isolamento & purificação , Recuperação e Remediação Ambiental/métodos , Poluentes do Solo/isolamento & purificação , Propriedades de Superfície , Fatores de Tempo
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