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1.
Sensors (Basel) ; 22(14)2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35890892

RESUMO

Civil engineering assets and geo-structures continually deteriorate during their lifetime, particularly in harsh environments that may be contaminated with corrosive substances. However, efficient and constant structural health monitoring and accurate prediction of the service-life of these assets can help to ensure their safety, performance, and health conditions and enable proper maintenance and rehabilitation. Nowadays, many of the largest cities throughout the world are situated in coastal zones, leading to a dramatic increase in the construction of nearshore geo-structures/infrastructures which are vulnerable to corrosion attacks resulting from salinity contamination. Additionally, seawater intrusion can threaten the quality and the sustainability of fresh groundwater resources, which are a crucial resource in coastal areas. To address these issues, detection of salinity in soil utilizing a novel polymer optical fibre Bragg grating (POFBG) sensor was investigated in this research. Experiments were carried out at different soil water contents with different salinities to assess the sensor's response in a representative soil environment. The sensitivity of the POFBG sensor to salinity concentrations in water and soil environment is estimated as 58 ± 2 pm/%. The average standard error value in salinity is calculated as 0.43% for the samples with different soil water contents. The results demonstrate that the sensor is a promising and practical tool for the measurement and monitoring with high precision of salinity contamination in soil.


Assuntos
Monitoramento Ambiental , Solo , Fibras Ópticas , Polímeros , Areia , Solo/química , Água
3.
Br J Clin Pharmacol ; 73(6): 874-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22360700

RESUMO

Clinical pharmacologists in universities play major roles in research and teaching and provide important contributions to National Health Service (NHS) activities, such as work for research ethics, drug and therapeutics, and clinical governance committees. Their research extends from preclinical studies using drugs to understand physiology and the mechanisms of disease to large-scale clinical trials and population studies. This work is truly translational, with a focus on drugs and medicines and an emphasis on efficacy and safety. The lack of an organ base has allowed clinical pharmacologists to follow their interests wherever they lead, but their visibility has been hampered by successive earlier versions of the General Medical Council's Tomorrow's Doctors document, which undermined some of the necessary scientific underpinning of medical practice and reduced the time clinical pharmacologists had to interact with medical students and recently qualified doctors at the point of choosing their careers. Additional problems have arisen from the stifling effect of the European Union Clinical Trials Directive, and its UK interpretation, on clinical research. For future success, clinical pharmacologists need to embrace translational research, use recent changes to Tomorrow's Doctors, linked to the creation of safe prescribing skills, to spend more face-to-face time with their students, fight for a simplification and proportionate regulation of research, and persuade doctors, health service planners and the government of the importance of clinical pharmacology for UK clinical research, the NHS, patient safety and creation of health and wealth.


Assuntos
Pesquisa Biomédica/métodos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Farmacologia Clínica/organização & administração , Papel Profissional , Pesquisadores/estatística & dados numéricos , Universidades , Pesquisa Biomédica/normas , Pesquisa Biomédica/estatística & dados numéricos , Ensaios Clínicos como Assunto , Avaliação Pré-Clínica de Medicamentos , Humanos , Reino Unido
4.
J Hepatol ; 38(1): 44-50, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12480559

RESUMO

BACKGROUND/AIMS: Altered vascular responses to vasopressor agents contribute to the pathogenesis of the circulatory dysfunction in cirrhosis. This study aims to assess the role of endogenous nitric oxide (NO) in the reduced vascular responsiveness to angiotensin II (ANG-II) in eight patients with preascitic cirrhosis compared with eight age- and sex-matched healthy controls. METHODS: Forearm blood flow (FBF) responses to sub-systemic, locally-active intra-brachial infusions of ANG-II were measured using venous occlusion plethysmography before and during the application of an 'NO-clamp', a balanced co-infusion of L-N(G)-monomethyl-arginine (a selective NO synthase inhibitor) and sodium nitroprusside (an exogenous NO donor) to block endogenous NO production and restore normal NO-mediated basal blood flow, respectively. RESULTS: Before applying the 'NO-clamp', ANG-II caused dose-dependent reductions of FBF in both groups (P<0.001) that were significantly attenuated in the cirrhotic patients (P=0.012). In the presence of the 'NO-clamp', the ANG-II-mediated vasoconstriction was enhanced in cirrhotic patients (P<0.01), unchanged in controls, and now similar in both groups. CONCLUSIONS: This study confirms that vasoconstriction to ANG-II is reduced in patients with preascitic cirrhosis, and suggests that this is principally due to enhanced NO generation mediated by ANG-II.


Assuntos
Angiotensina II/farmacologia , Cirrose Hepática/fisiopatologia , Óxido Nítrico/metabolismo , Vasoconstrição , Vasoconstritores/farmacologia , Angiotensina II/administração & dosagem , Angiotensina II/sangue , Ascite , Estudos de Casos e Controles , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Feminino , Antebraço/irrigação sanguínea , Humanos , Cirrose Hepática/sangue , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional/efeitos dos fármacos , Vasoconstritores/administração & dosagem , Vasoconstritores/sangue , ômega-N-Metilarginina/farmacologia
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