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1.
J Radiol Prot ; 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39047756

RESUMO

This study reports the performance of 7 types of consumer grade passive Electronic Radon Integrating Monitors, ERIM (AlphaE, AER Plus, Canary, Corentium Pro, Radon Scout Home, Ramon and Wave) and passive etched track radon detectors. All monitors and passive radon detectors were exposed side by side for 2 periods of 3 months under controlled conditions in the UKHSA radon chamber and in a stainless steel container to an average radon concentration of 4781 Bq m-3 and 166 Bq m-3, respectively. The performance of each individual monitor was compared with Atmos 12DPX and AlphaGUARD P30 reference instruments. The performance of the monitors was evaluated by estimating the biased, precision and measurement errors of each type. It was found that UKHSA passive radon detectors showed excellent performance (measurement error < 10%) at both higher and lower exposures. The AlphaE, Canary and Ramon showed excellent performance, with measurement error < 10%, when they were exposed to radon concentrations between 4000 Bq m-3 and 6000 Bq m-3 in the UKHSA radon chamber. However, when the monitors were exposed to radon levels below the UK radon Action Level of 200 Bq m-3, the only ERIM which had a measurement error <10% was the Radon Scout Home. All other monitors showed a significant decrease in their performance with measurement errors ranging between 20% and 50%. The calibration factor, which is the ratio between the measured value (background is subtracted) and the reference value, was also studied. It was found that the calibration factors of individual monitors changed significantly. Calibration measurements in 2019 and in 2023 found that the percentage change varied between -46% and +63%. This shows the importance of initial and regular calibration, and maintenance of the monitors. .

2.
Theor Appl Genet ; 134(7): 2063-2077, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33770189

RESUMO

KEY MESSAGE: Genomic analysis of Mediterranean oats reveals high genetic diversity and three loci for adaptation to this environment. This information together with phenotyping and passport data, gathered in an interactive map, will be a vital resource for oat genetic improvement. During the twentieth century, oat landraces have increasingly been replaced by modern cultivars, resulting in loss of genetic diversity. However, landraces have considerable potential to improve disease and abiotic stress tolerance and may outperform cultivars under low input systems. In this work, we assembled a panel of 669 oat landraces from Mediterranean rim and 40 cultivated oat varieties and performed the first large-scale population genetic analysis of both red and white oat types of Mediterranean origin. We created a public database associated with an interactive map to visualize information for each accession. The oat collection was genotyped with 17,288 single-nucleotide polymorphism (SNP) loci to evaluate population structure and linkage disequilibrium (LD); to perform a genome-wide association study (GWAs) for heading date, a key character closely correlated with performance in this drought-prone area. Population genetic analysis using both structure and PCA distinguished two main groups composed of the red and white oats, respectively. The white oat group was further divided into two subgroups. LD decay was slower within white lines in linkage groups Mrg01, 02, 04, 12, 13, 15, 23, 33, whereas it was slower within red lines in Mrg03, 05, 06, 11, 21, 24, and 28. Association analysis showed several significant markers associated with heading date on linkage group Mrg13 in white oats and on Mrg01 and Mrg08 in red oats.


Assuntos
Avena/genética , Genética Populacional , Sementes/crescimento & desenvolvimento , Estudos de Associação Genética , Ligação Genética , Marcadores Genéticos , Genótipo , Haplótipos , Desequilíbrio de Ligação , Região do Mediterrâneo , Polimorfismo de Nucleotídeo Único
3.
Cereb Cortex ; 30(4): 2452-2464, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-31746324

RESUMO

Inhibitory interneurons can evoke vasodilation and vasoconstriction, making them potential cellular drivers of neurovascular coupling. However, the specific regulatory roles played by particular interneuron subpopulations remain unclear. Our purpose was therefore to adopt a cell-specific optogenetic approach to investigate how somatostatin (SST) and neuronal nitric oxide synthase (nNOS)-expressing interneurons might influence the neurovascular relationship. In mice, specific activation of SST- or nNOS-interneurons was sufficient to evoke hemodynamic changes. In the case of nNOS-interneurons, robust hemodynamic changes occurred with minimal changes in neural activity, suggesting that the ability of blood oxygen level dependent functional magnetic resonance imaging (BOLD fMRI) to reliably reflect changes in neuronal activity may be dependent on type of neuron recruited. Conversely, activation of SST-interneurons produced robust changes in evoked neural activity with shallow cortical excitation and pronounced deep layer cortical inhibition. Prolonged activation of SST-interneurons often resulted in an increase in blood volume in the centrally activated area with an accompanying decrease in blood volume in the surrounding brain regions, analogous to the negative BOLD signal. These results demonstrate the role of specific populations of cortical interneurons in the active control of neurovascular function.


Assuntos
Córtex Cerebral/citologia , Córtex Cerebral/fisiologia , Interneurônios/fisiologia , Inibição Neural/fisiologia , Acoplamento Neurovascular/fisiologia , Animais , Córtex Cerebral/química , Feminino , Interneurônios/química , Imageamento por Ressonância Magnética/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Óxido Nítrico Sintase Tipo I/análise , Imagem Óptica/métodos , Optogenética/métodos
4.
J Radiol Prot ; 32(3): 275-87, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22809737

RESUMO

The patterns of seasonal variation of radon concentrations were measured in 91 homes in five regions of the UK over a period of two years. The results showed that there was no significant difference between the regions in the pattern or magnitude of seasonal variation in radon concentrations. The arithmetic mean variation was found to be close to that found previously in the UK national survey. Differences in the pattern between the two years of the study were not significant. Two-thirds of homes in the study followed the expected pattern of high radon in the winter and low radon in the summer. Most of the rest showed little seasonal variation, and a few showed a reversed seasonal pattern. The study does not provide any clear evidence for the recorded house characteristics having an effect on the seasonal variation in radon concentrations in UK homes, though the statistical power for determining such effects is limited in this study. The magnitude of the seasonal variation varied widely between homes. Analysis of the individual results from the homes showed that because of the wide variation in the amount of seasonal variation, applying seasonal correction factors to the results of three-month measurements can yield only relatively small improvements in the accuracy of estimates of annual mean concentrations.


Assuntos
Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Habitação , Radônio/análise , Estações do Ano , Humanos , Reino Unido
5.
Early Hum Dev ; 163: 105491, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34710831

RESUMO

Following the first peak of the COVID-19 pandemic, reports from around the world suggested a reduction in preterm deliveries during lockdown periods. We reviewed preterm admissions to a large tertiary neonatal unit in inner North East London during two United Kingdom (UK) national lockdowns in 2020 and 2021. We found no evidence of difference in admissions during two national lockdowns compared to previous years. Based on these findings, we recommend that neonatal services remain as vigilant and prepared as ever for the unpredictable nature of preterm birth, and their staff protected to provide this highly specialist care.


Assuntos
COVID-19 , Controle de Doenças Transmissíveis , Necessidades e Demandas de Serviços de Saúde/estatística & dados numéricos , Terapia Intensiva Neonatal/estatística & dados numéricos , Humanos , Recém-Nascido , Pandemias , Nascimento Prematuro
6.
J Cogn Enhanc ; 4(3): 235-249, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32747876

RESUMO

The non-invasive neuromodulation technique tDCS offers the promise of a low cost tool for both research and clinical applications in psychology, psychiatry and neuroscience. However, findings regarding its efficacy are often equivocal. A key issue is that the clinical and cognitive applications studied are often complex and thus effects of tDCS are difficult to predict given its known effects on the basic underlying neurophysiology, namely alterations in cortical inhibition-excitation balance. As such, it may be beneficial to assess the effects of tDCS in tasks whose performance has a clear link to cortical inhibition-excitation balance such as the visual orientation discrimination task (ODT). In prior studies in our laboratory no practise effects were found during 2 consecutive runs of the ODT, thus in the current investigation, to examine the effects of tDCS, subjects received 10 minutes of 2mA occipital tDCS (sham, anode, cathode) between a first and second run of ODT. Surprisingly, subjects' performance significantly improved in the second run of ODT compared to the first one regardless of the tDCS stimulation type they received (anodal, cathodal, or sham-tDCS). Possible causes for such an improvement could have been due to either a generic 'placebo' effect of tDCS (as all subjects received some form of tDCS) or an increased delay period between the two runs of ODT of the current study compared to our previous work (10 minutes duration required to administer tDCS as opposed to ~2 minutes in previous studies as a 'break'). As such, we tested these two possibilities with a subsequent experiment in which subjects received 2 minutes or 10 minutes delay between the 2 runs (with no tDCS) or 10 minutes of sham-tDCS. Only sham-tDCS resulted in improved performance thus these data add to a growing literature suggesting that tDCS has powerful placebo effect that may occur even in the absence of active cortical modulation.

7.
Radiat Prot Dosimetry ; 177(1-2): 140-143, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28981884

RESUMO

The Vale of Pickering in Yorkshire, England has been identified as a potential area for shale gas extraction. Public Health England joined a collaboration led by the British Geological Survey for environmental baseline monitoring near the potential shale gas extraction site following a grant award from UK Government Department for Business, Energy and Industrial Strategy. The analysis of results for the first 6 months of indoor monitoring indicated that the results followed a log-normal distribution. The numbers of homes found to be at or above the Action Level followed the numbers predicted by the radon potential maps. The results from the measurements of outdoor air in this study indicated that the radon concentrations are slightly higher than previously measured but close to the detection limit of the technique.


Assuntos
Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Contaminação Radioativa do Ar/análise , Exposição Ambiental/análise , Sedimentos Geológicos/análise , Monitoramento de Radiação/métodos , Inglaterra , Habitação , Humanos , Radônio/análise
8.
Appl Radiat Isot ; 64(10-11): 1102-7, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16580217

RESUMO

For the first time, a comparison of radon activity concentration in air has been performed within the scope of Euromet. In the project 657, 'Comparison of calibration facilities for the radon activity concentration,' 12 participants from 9 countries compared different radon reference atmospheres at 1, 3 and 10 k Bq m-3 via a transfer standard. The comparison was listed as BIPM supplementary comparison EUROMET.RI(II)-S1. The results of most participants are correlated due to common traceability to one single radon gas standard producer. This makes a careful correlation analysis necessary to achieve an appropriate comparison reference value. The results of the comparison as well as the complex analysis of the correlated set of data is presented and discussed.


Assuntos
Poluentes Radioativos do Ar/análise , Poluentes Radioativos do Ar/normas , Cooperação Internacional , Monitoramento de Radiação/métodos , Monitoramento de Radiação/normas , Radônio/análise , Radônio/normas , Calibragem/normas , Europa (Continente) , Guias como Assunto , Doses de Radiação , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
J Clin Oncol ; 3(6): 813-7, 1985 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2989445

RESUMO

Nasopharyngeal carcinoma (NPC) is a human neoplasm closely associated with Epstein-Barr virus (EBV). Human leukocyte interferon (IFN) has known antiviral and antineoplastic properties. After initial IFN treatment in one NPC patient demonstrated acceptably low toxicity, 12 additional patients were treated on a protocol with IFN, 10 X 10(6) units intramuscularly (IM) daily for 30 days. IFN did not affect serum anti-EBV antibody titers (IgA and IgG antiviral capsid and early antigens). Of six patients tested, none was found to excrete EBV in saliva before, during, or after IFN. Four patients had measurable tumor regression (two partial responses and two minor responses), three had stable disease, and five patients plus the initial preprotocol patient had progressive disease. Toxicity included fever, fatigue, and myalgias in all patients, thrombocytopenia in two patients, and neutropenia in three patients. Three patients were withdrawn from the study, one each for severe fatigue, neutropenia, and hypotension. This study demonstrates that IFN has sufficient activity in advanced NPC to justify further investigation.


Assuntos
Herpesvirus Humano 4/imunologia , Interferon Tipo I/uso terapêutico , Neoplasias Nasofaríngeas/terapia , Infecções Tumorais por Vírus/terapia , Adulto , Idoso , Animais , Anticorpos Antivirais/análise , Feminino , Humanos , Interferon Tipo I/efeitos adversos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/imunologia , Neoplasias Nasofaríngeas/patologia , Metástase Neoplásica , Recidiva Local de Neoplasia/terapia
10.
Proc Biol Sci ; 263(1370): 601-6, 1996 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-8677260

RESUMO

Computational models of activity-dependent competitive neural plasticity typically impose competition in networks in which plasticity is accommodated by permitting changes in the efficacies of synapses in an anatomically fixed network. This is despite the fact that much evidence suggests that neurons compete for neurotrophins, during both target innervation and activity-dependent synaptic re-arrangement, which influence the sprouting and retraction of axonal processes. We therefore present a new approach to the computational modelling of competitive neural plasticity which permits neurons to compete explicitly for neurotrophins. This competition is associated with the sprouting and retraction of axonal processes. Because there is much uncertainty regarding the basic mechanisms, we adopt the powerful machinery of statistical mechanics to avoid the need to address these issues. We show that such an approach can readily account for a wide range of plasticity phenomena in a range of systems, including the results of various pharmacological manipulations.


Assuntos
Modelos Neurológicos , Plasticidade Neuronal/fisiologia , Animais , Mapeamento Encefálico , Simulação por Computador , Dedos/inervação , Corpos Geniculados/fisiologia , Matemática , Primatas , Córtex Somatossensorial/crescimento & desenvolvimento , Córtex Somatossensorial/fisiologia
11.
Theor Appl Genet ; 104(1): 67-83, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12579430

RESUMO

Drought stress during the reproductive stage is one of the most important environmental factors reducing the grain yield and yield stability of pearl millet. A QTL mapping approach has been used in this study to understand the genetic and physiological basis of drought tolerance in pearl millet and to provide a more-targeted approach to improving the drought tolerance and yield of this crop in water-limited environments. The aim was to identify specific genomic regions associated with the enhanced tolerance of pearl millet to drought stress during the flowering and grain-filling stages. Testcrosses of a set of mapping-population progenies, derived from a cross of two inbred pollinators that differed in their response to drought, were evaluated in a range of managed terminal drought-stress environments. A number of genomic regions were associated with drought tolerance in terms of both grain yield and its components. For example, a QTL associated with grain yield per se and for the drought tolerance of grain yield mapped on linkage group 2 and explained up to 23% of the phenotypic variation. Some of these QTLs were common across stress environments whereas others were specific to only a particular stress environment. All the QTLs that contributed to increased drought tolerance did so either through better than average maintenance (compared to non-stress environments) of harvest index, or harvest index and biomass productivity. It is concluded that there is considerable potential for marker-assisted backcross transfer of selected QTLs to the elite parent of the mapping population and for their general use in the improvement of pearl millet productivity in water-limited environments.

12.
Accid Anal Prev ; 25(3): 277-88, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8323662

RESUMO

A model is proposed for the description of effects of safety measures introduced into a road transport system. The model explains the motives of road users' risk compensation towards the measures, and indicates when behavioural adaptation is likely to take place and its effects on road safety programmes. At its core the model has the notion that when a transport system is changed by engineering safety measures, road users do not respond only in the direction towards safety improvement but respond, in general, with three possible ways of behavioural adaptations, one of them towards more risk taking. Supported by illustrative examples, it also suggests that due to risk compensation, engineering safety measures alone are usually not sufficient, and, hopefully, carefully designed motivational safety measures can give us chances to modify road users' behaviour to make traffic safer.


Assuntos
Acidentes de Trânsito/prevenção & controle , Condução de Veículo/psicologia , Modelos Psicológicos , Assunção de Riscos , Segurança , Ergonomia , Humanos , Motivação
13.
Chemosphere ; 42(4): 397-403, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11100791

RESUMO

A new type of photocatalytic reactor, the spinning disc reactor (SDR), was used to degrade aqueous solutions of 4-chlorophenol and salicylic acid. The efficiency of the photocatalytic process depends on the type of UV source used. Lamps supplying shorter wavelength UV radiation are more efficient than those whose emissions lay mainly in the near UV region. The method used to coat the disc of the SDR does not meet its operational requirements. The characteristics of the turbulent liquid films produced in the SDR reduce the influence of mass transfer over the overall photocatalytic process.


Assuntos
Fármacos Fotossensibilizantes , Titânio , Raios Ultravioleta , Catálise , Clorofenóis/química , Ceratolíticos/química , Ácido Salicílico/química
18.
Philos Trans R Soc Lond B Biol Sci ; 363(1492): 703-16, 2008 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-17761467

RESUMO

Using cereal crops as examples, we review the breeding for tolerance to the abiotic stresses of low nitrogen, drought, salinity and aluminium toxicity. All are already important abiotic stress factors that cause large and widespread yield reductions. Drought will increase in importance with climate change, the area of irrigated land that is salinized continues to increase, and the cost of inorganic N is set to rise. There is good potential for directly breeding for adaptation to low N while retaining an ability to respond to high N conditions. Breeding for drought and salinity tolerance have proven to be difficult, and the complex mechanisms of tolerance are reviewed. Marker-assisted selection for component traits of drought in rice and pearl millet and salinity tolerance in wheat has produced some positive results and the pyramiding of stable quantitative trait locuses controlling component traits may provide a solution. New genomic technologies promise to make progress for breeding tolerance to these two stresses through a more fundamental understanding of underlying processes and identification of the genes responsible. In wheat, there is a great potential of breeding genetic resistance for salinity and aluminium tolerance through the contributions of wild relatives.


Assuntos
Adaptação Fisiológica , Agricultura/métodos , Cruzamento/métodos , Produtos Agrícolas/fisiologia , Grão Comestível/genética , Plantas Geneticamente Modificadas , Alumínio/toxicidade , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Desastres , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/fisiologia , Nitrogênio/metabolismo , Sais/análise , Seleção Genética , Solo/análise
19.
Theor Appl Genet ; 117(2): 283-96, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18438637

RESUMO

The already available comprehensive genome sequence information of model crops along with the transcriptomic resource from other crops provides an excellent opportunity for comparative genome analysis. We studied the synteny between each of the four major sorghum staygreen quantitative trait loci (QTL) regions with that in the rice genome and attempted to increase marker density around the QTL with genic-microsatellites from the sorghum transcriptomic resource using the rice genome as template. For each of the sorghum QTL regions, the reported RFLP markers were compiled, used for sequence similarity searches against the rice genome which identified syntenous regions on rice chromosome 1 for Stg1 and Stg2 QTL, on chromosome 9 for Stg3 QTL, and on chromosome 11 for Stg4 QTL. Using the Gramene genome browsing tool, 869 non-redundant sorghum expressed sequence tags (ESTs) were selected and 50 genic-microsatellites (18, 12, 15, and 5, for Stg1, Stg2, Stg3, and Stg4 QTL, respectively) could be developed. We could experimentally establish synteny of the Stg1, Stg2, Stg3, and Stg4 QTL regions with that of the rice genome by mapping ten polymorphic genic-microsatellite markers (20%) to the positions of the staygreen QTL. The simple strategy demonstrated in the present study could readily be extrapolated to other cereals of the Poaceae family. The markers developed in this study provide a basis for the isolation of genes underling these QTL using an association study or map-based gene isolation approach, and create an additional option for MAS of the staygreen trait in sorghum.


Assuntos
Genes de Plantas , Repetições de Microssatélites/genética , Oryza/genética , Locos de Características Quantitativas/genética , Sorghum/genética , Mapeamento Cromossômico , Cromossomos Artificiais Bacterianos , Células Clonais , Etiquetas de Sequências Expressas , Ligação Genética , Marcadores Genéticos , Polimorfismo de Fragmento de Restrição , Sintenia/genética
20.
Diabet Med ; 24(11): 1229-34, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17725628

RESUMO

BACKGROUND: Maternal diabetes increases the risk of pre-eclampsia and abnormalities of fetal growth. We studied the additional impact of maternal vascular disease on these risks. METHODS: The first viable (> 23 weeks) pregnancies of 138 women with Type 1 diabetes mellitus (Type 1 DM), delivered between 1994 and 2003 at the Queen's Medical Centre, Nottingham, UK were studied. Women were divided into groups with and without vascular disease (retinopathy and/or nephropathy and/or pre-existing hypertension). Primary outcomes were pre-eclampsia and fetal customized birthweight percentile (cbp) (adjusted for maternal weight, height, parity, ethnicity, gestational age and gender). Secondary outcomes were perinatal outcome (miscarriage, intrauterine or neonatal death), preterm birth, birth asphyxia, neonatal hypoglycaemia and delivery mode. RESULTS: Women with vascular disease were more likely to develop pre-eclampsia (OR 3.5; CI 1.28-9.53) and deliver infants with lower cbp (median 89.0, range 0-100 vs. 98.0, range 0-100; P < or = 0.005). Infants were less likely to be macrosomic (OR 0.46; CI 0.224-0.928) but more likely to have intrauterine growth restriction (IUGR; OR 6.0; CI 1.54-23.33). Women with vascular disease had higher Caesarean section rates (90 vs. 56%, P < or = 0.001). CONCLUSIONS/INTERPRETATION: Women with Type 1 DM and vascular disease are at greater risk of pre-eclampsia and pathological fetal growth. This should influence counselling and merit increased pregnancy surveillance.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Angiopatias Diabéticas/complicações , Retardo do Crescimento Fetal/etiologia , Pré-Eclâmpsia/etiologia , Complicações Cardiovasculares na Gravidez , Gravidez em Diabéticas , Adolescente , Adulto , Diabetes Mellitus Tipo 1/metabolismo , Feminino , Humanos , Recém-Nascido , Gravidez , Resultado da Gravidez , Fatores de Risco
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