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1.
Cell Death Dis ; 10(5): 334, 2019 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-31000691

RESUMO

Following the publication of this article [1], it was noted that the author list was incomplete and was missing the following author.

2.
Soil Use Manag ; 32(1): 106-117, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27570358

RESUMO

Reducing tillage intensity offers the possibility of moving towards sustainable intensification objectives. Reduced tillage (RT) practices, where the plough is not used, can provide a number of environmental and financial benefits, particularly for soil erosion control. Based on 2010 harvest year data from the nationally stratified Farm Business Survey and drawing on a sub-sample of 249 English arable farmers, we estimate that approximately 32% of arable land was established under RT, with 46% of farms using some form of RT. Farms more likely to use some form of RT were larger, located in the East Midlands and South East of England and classified as 'Cereals' farms. Application of RT techniques was not determined by the age or education level of the farmer. Individual crops impacted the choice of land preparation, with wheat and oilseed rape being more frequently planted after RT than field beans and root crops, which were almost always planted after ploughing. This result suggests there can be limitations to the applicability of RT. Average tillage depth was only slightly shallower for RT practices than ploughing, suggesting that the predominant RT practices are quite demanding in their energy use. Policy makers seeking to increase sustainable RT uptake will need to address farm-level capital investment constraints and target policies on farms growing crops, such as wheat and oilseed rape, that are better suited to RT practices.

3.
Rev Sci Instrum ; 86(4): 045108, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25933898

RESUMO

A detailed description of a new pulsed supersonic uniform gas expansion system is presented together with the experimental validation of the setup by applying the CRESU (French acronym for Cinétique de Réaction en Ecoulement Supersonique Uniforme or Reaction Kinetics in a Uniform Supersonic Flow) technique to the gas-phase reaction of OH radicals with 1-butene at ca. 23 K and 0.63 millibars of helium (carrier gas). The carrier gas flow, containing negligible mixing ratios of OH-precursor and 1-butene, is expanded from a high pressure reservoir (337 millibars) to a low pressure region (0.63 millibars) through a convergent-divergent nozzle (Laval type). The novelty of this experimental setup is that the uniform supersonic flow is pulsed by means of a Teflon-coated aerodynamic chopper provided with two symmetrical apertures. Under these operational conditions, the designed Laval nozzle achieves a temperature of (22.4 ± 1.4) K in the gas jet. The spatial characterization of the temperature and the total gas density within the pulsed uniform supersonic flow has also been performed by both aerodynamical and spectroscopic methods. The gas consumption with this technique is considerably reduced with respect to a continuous CRESU system. The kinetics of the OH+1-butene reaction was investigated by the pulsed laser photolysis/laser induced fluorescence technique. The rotation speed of the disk is temporally synchronized with the exit of the photolysis and the probe lasers. The rate coefficient (k(OH)) for the reaction under investigation was then obtained and compared with the only available data at this temperature.

4.
Environ Int ; 82: 35-40, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26004992

RESUMO

Concern about children's exposure to arsenic (As) from wood treated with chromated-copper-arsenate (CCA) led to its withdrawal from residential use in 2004. However, due to its effectiveness, millions of American homes still have CCA-wood decks on which children play. This study evaluated the effects of three deck-cleaning methods on formation of dislodgeable As and hexavalent chromium (CrVI) on CCA-wood surfaces and in leachate. Initial wipes from CCA-wood wetted with water showed 3-4 times more dislodgeable As than on dry wood. After cleaning with a bleach solution, 9.8-40.3µg/100cm(2) of CrVI was found on the wood surface, with up to 170µg/L CrVI in the leachate. Depending on the cleaning method, 699-2473mg of As would be released into the environment from cleaning a 18.6-m(2)-deck. Estimated As doses in children aged 1-6 after 1h of playing on a wet CCA-wood deck were 0.25-0.41µg/kg. This is the first study to identify increased dislodgeable As on wet CCA-wood and to evaluate dislodgeable CrVI after bleach application. Our data suggest that As and CrVI in 25-year old CCA-wood still show exposure risks for children and potential for soil contamination.


Assuntos
Arseniatos/efeitos adversos , Arsênio/efeitos adversos , Criança , Cromo , Compostos de Cromo , Habitação , Humanos , Jogos e Brinquedos , Risco , Madeira
5.
S Afr Med J ; 103(1): 43-6, 2012 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-23237124

RESUMO

BACKGROUND: HTLV-1 associated myelopathy (HAM), or tropical spastic paraparesis, is caused by a retrovirus, the human T-cell lymphotropic virus (HTLV). Although patients with HAM and HIV infection have been described, to our knowledge no direct comparison has been made between patients who are HIV positive and suffering from HAM (HHAM) v. those who are HIV negative and suffering from HAM. AIM: We aimed to compare clinical and radiological findings in HIV-positive and -negative patients with HAM. METHODS: Adult patients who presented to the Neurology Unit at the Steve Biko Academic Hospital from May 2005 to June 2012 with a progressive myelopathy and HTLV seropositivity were retrospectively identified and their clinical and radiological data were collected and reviewed. RESULTS: 21 patients with HAM were identified, of whom 9 were HIV-positive and 11 HIV-negative. One patient, whose HIV status had not been established, was not included in the study. Although the trend did not reach statistical significance, co-infected patients tended to present at an earlier age (HHAM 6/9 (66%) <40 years old; HAM 2/11 (18%) <40 years old) and presented to hospital earlier (HHAM 6/9 (66%) < 3 years symptomatic; HAM 7/11 (63%) > 3 years symptomatic). Cord atrophy occurred in 7/8 dually infected patients and 8/10 HIV-negative patients. CONCLUSION: Although the study is limited by the small number of patients, co-infected patients tended to have a younger age of onset and to present to hospital sooner, and thoracic cord atrophy was very common.


Assuntos
Soronegatividade para HIV , Soropositividade para HIV/epidemiologia , HIV/imunologia , Paraparesia Espástica Tropical/epidemiologia , Centros de Atenção Terciária/estatística & dados numéricos , Adulto , Feminino , Soropositividade para HIV/complicações , Humanos , Incidência , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Paraparesia Espástica Tropical/complicações , Paraparesia Espástica Tropical/diagnóstico , Estudos Retrospectivos , África do Sul/epidemiologia
6.
Waste Manag ; 30(11): 2247-54, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20472418

RESUMO

The magnitude and composition of a region's construction and demolition (C&D) debris should be understood when developing rules, policies and strategies for managing this segment of the solid waste stream. In the US, several national estimates have been conducted using a weight-per-construction-area approximation; national estimates using alternative procedures such as those used for other segments of the solid waste stream have not been reported for C&D debris. This paper presents an evaluation of a materials flow analysis (MFA) approach for estimating C&D debris generation and composition for a large region (the US). The consumption of construction materials in the US and typical waste factors used for construction materials purchasing were used to estimate the mass of solid waste generated as a result of construction activities. Debris from demolition activities was predicted from various historical construction materials consumption data and estimates of average service lives of the materials. The MFA approach estimated that approximately 610-78 × 10(6)Mg of C&D debris was generated in 2002. This predicted mass exceeds previous estimates using other C&D debris predictive methodologies and reflects the large waste stream that exists.


Assuntos
Materiais de Construção , Eliminação de Resíduos/métodos , Gerenciamento de Resíduos/métodos , Meio Ambiente , Monitoramento Ambiental , Hidrocarbonetos/análise , Resíduos Industriais/análise , Modelos Teóricos , Aço/análise , Fatores de Tempo , Estados Unidos , Resíduos/análise , Madeira/análise
7.
J Evol Biol ; 20(5): 1751-62, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17714293

RESUMO

We analysed the diversification of squamate reptiles (7488 species) based on a new molecular phylogeny, and compared the results to similar estimates for passerine birds (5712 species). The number of species in each of 36 squamate lineages showed no evidence of phylogenetic conservatism. Compared with a random speciation-extinction process with parameters estimated from the size distribution of clades, the alethinophidian snakes (2600 species) were larger than expected and 13 clades, each having fewer than 20 species, were smaller than expected, indicating rate heterogeneity. From a lineage-through-time plot, we estimated that a provisional rate of lineage extinction (0.66 per Myr) was 94% of the rate of lineage splitting (0.70 per Myr). Diversification in squamate lineages was independent of their stem age, but strongly related to the area of the region within which they occur. Tropical vs. temperate latitude exerted a marginally significant influence on species richness. In comparison with passerine birds, squamates share several clade features, including: (1) independence of species richness and age; (2) lack of phylogenetic signal with respect to clade size; (3) general absence of exceptionally large clades; (4) over-representation of small clades; (5) influence of region size on clade size; and (6) similar rates of speciation and extinction. The evidence for both groups suggests that clade size has achieved long-term equilibrium, suggesting negative feedback of species richness on the rate of diversification.


Assuntos
Evolução Biológica , Filogenia , Répteis/classificação , Animais , Biodiversidade , Simulação por Computador , Extinção Biológica , Especiação Genética , Modelos Biológicos , Passeriformes/classificação , Passeriformes/genética , Análise de Regressão , Répteis/genética
8.
Theor Appl Genet ; 108(7): 1249-55, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-14663558

RESUMO

Diallel analysis was used to investigate the genetic control of in vitro shoot regeneration in Brassica oleracea. Twelve doubled haploid (DH) lines, selected to include a range of genotypes with differing shoot regeneration potentials, were crossed reciprocally to produce 132 F(1) and 12 selfed, DH families. Cotyledonary petioles from 4-day-old seedlings, from all families, were excised and maintained on MS medium supplemented with 2 mg/l BAP. Explants were scored after 44 days for both the presence or absence of shoots and the number of regenerating shoots per explant. Diallel analysis showed both shoot regeneration and the production of multiple shoots to be controlled by additive and dominant gene effects, with additive effects being more important. Additive gene effects accounted for 71% and 77% of the genetic variation observed within the diallel for shoot regeneration and multiple shoot regeneration, respectively. By investigating the shoot regeneration potential of subsequent backcross and F(2) populations, the ability to introduce and increase shoot regeneration potential into otherwise recalcitrant lines was demonstrated.


Assuntos
Brassica/genética , Cotilédone/fisiologia , Variação Genética , Brotos de Planta/fisiologia , Regeneração/genética , Análise de Variância , Brassica/fisiologia , Cruzamentos Genéticos
10.
Theor Appl Genet ; 108(4): 644-50, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14534750

RESUMO

The genetic control and heritability of Agrobacterium tumefaciens susceptibility was investigated using a doubled haploid (DH) mapping population of Brassica oleracea and the associated RFLP map. Preliminary studies were carried out by analysis of an 8 x 8 diallel, for which the parental lines were selected to include a range of susceptibilities to A. tumefaciens. The variation observed within the diallel was attributed to both additive and dominant gene effects, with additive gene effects being more important. A broad sense heritability value of 0.95 suggested that 95% of the observed variation was due to genetic effects, with just 5% attributed to non-genetic or environmental effects. A high narrow-sense heritability value of 0.79 suggested that 79% of this trait was controlled by additive gene effects and, therefore, the potential to introduce this trait into breeding material is high. Fifty-nine DH lines from the mapping population were screened for susceptibility towards A. tumefaciens. Variation in susceptibility was observed across the population. The results of the DH screen were entered into the mapping programme MAPQTL and a highly significant quantitative trait loci (QTL) associated with susceptibility to A. tumefaciens was identified on linkage group 09. The use of substitution lines covering this region confirmed the location of this QTL. This work shows that susceptibility to A. tumefaciens is a heritable trait, and the transfer of susceptibility into resistant lines is demonstrated. These findings may help to overcome genotype restrictions to genetic transformation.


Assuntos
Agrobacterium tumefaciens , Brassica/genética , Imunidade Inata/genética , Doenças das Plantas/microbiologia , Mapeamento Cromossômico , Tumores de Planta/genética , Locos de Características Quantitativas/genética
11.
Proc Biol Sci ; 270 Suppl 2: S202-5, 2003 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-14667383

RESUMO

A greater understanding of the tightly linked trophic groups of anaerobic and aerobic bacteria residing in municipal solid waste landfills will increase our ability to control methane emissions and pollutant fate in these environments. To this end, we characterized the composition of methanogenic and methanotrophic bacteria in samples taken from two regions of a municipal solid waste landfill that varied in age. A method combining polymerase chain reaction amplification, restriction fragment length polymorphism analysis and phylogenetic analysis was used for this purpose. 16S rDNA sequence analysis revealed a rich assemblage of methanogens in both samples, including acetoclasts, H2/CO2-users and formate-users in the newer samples and H2/CO2-users and formate-users in the older samples, with closely related genera including Methanoculleus, Methanofollis, Methanosaeta and Methanosarcina. Fewer phylotypes of type 1 methanotrophs were observed relative to type 2 methanotrophs. Most type 1 sequences clustered within a clade related to Methylobacter, whereas type 2 sequences were broadly distributed among clades associated with Methylocystis and Methylosinus species. This genetic characterization tool promises rapid screening of landfill samples for genotypes and, therefore, degradation potentials.


Assuntos
Ecossistema , Euryarchaeota/genética , Filogenia , Sequência de Bases , Primers do DNA , DNA Ribossômico/genética , Euryarchaeota/fisiologia , Florida , Dados de Sequência Molecular , Polimorfismo de Fragmento de Restrição , Análise de Sequência de DNA
13.
Waste Manag ; 21(8): 703-15, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11699628

RESUMO

The objective of this study was to characterize recovered soil fines from construction and demolition (C&D) waste recycling facilities for trace organic pollutants. Over a period of 18 months, five sampling trips were made to 14 C&D waste recycling facilities in Florida. Screened soil fines were collected from older stockpiles and newly generated piles at the sites. The samples were analyzed for the total concentration (mg/kg) of a series of volatile organic compound (VOCs) and semi-volatile organic compounds (semi-VOCs). The synthetic precipitation leaching procedure (SPLP) test was also performed to evaluate the leachability of the trace organic chemicals. During the total analysis only a few volatile organic compounds were commonly found in the samples (trichlorofluoromethane, toluene, 4-isopropyltoluene, trimethylbenzene, xylenes, and methylene chloride). A total of nine VOCs were detected in the leaching test. Toluene showed the highest leachability among the compounds (61.3-92.0%), while trichlorofluoromethane, the most commonly detected compound from both the total and leaching tests, resulted in the lowest leachability (1.4-39.9%). For the semi-VOC analysis, three base-neutral semi-VOC compounds (bis(2-ethylhexyl)phthalate, butyl benzyl phthalate, and di-n-butyl phthalate) and several PAHs (acenaphthene, pyrene, fluoranthene, and phenanthrene) were commonly detected in C&D fines samples. These compounds also leached during the SPLP leaching test (0.1-25%). No acid extractable compounds, pesticides, or PCBs were detected. The results of this study were further investigated to assess risk from land applied recovered soil fines by comparing total and leaching concentrations of recovered soil fines samples to risk-based standards. The results of this indicate that the organic chemicals in recovered soil fines from C&D debris recycling facilities were not of a major concern in terms of human risk and leaching risk to groundwater under reuse and contact scenarios.


Assuntos
Conservação dos Recursos Naturais , Arquitetura de Instituições de Saúde , Manufaturas , Compostos Orgânicos/análise , Poluentes do Solo/análise , Xenobióticos/análise , Monitoramento Ambiental , Humanos , Saúde Pública , Medição de Risco , Volatilização
14.
J Trop Pediatr ; 47(5): 304-6, 2001 10.
Artigo em Inglês | MEDLINE | ID: mdl-11695733

RESUMO

The rate of breastfeeding initiation and continuation through the first 6 months of life were assessed via interview and telephone follow-up in a prospective study of 130 mothers who consecutively delivered in hospital in Fujairah, UAE. The rate of initiation (83.2 per cent) and continuation at 2 months (72.6 per cent) was not significantly different from earlier studies. However, the rate of breastfeeding at 6 months (46.9 per cent) was lower than a 1992 study (p = 0.02). There were no significant associated factors with not breastfeeding at discharge from the maternity hospital and 2 months later. However, a significant inverse relationship with the level of general education of the mother for breastfeeding at 6 months was found, which is in contradistinction to Western countries where the rate of breastfeeding rises with increasing general education. This has implications for the type and targeting of future breastfeeding education programmes.


Assuntos
Aleitamento Materno , Conhecimentos, Atitudes e Prática em Saúde , Adulto , Análise de Variância , Distribuição de Qui-Quadrado , Feminino , Humanos , Recém-Nascido , Estudos Prospectivos , Emirados Árabes Unidos
16.
East Mediterr Health J ; 7(4-5): 662-70, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-15332764

RESUMO

This study defined the baseline level of knowledge about diabetes and the perceived effectiveness of sources of diabetes information in an urban primary health care centre in Al-Ain. A validated questionnaire was administered to 300 randomly chosen adult patients with diabetes. Patient knowledge about diabetes was directly related to their level of general education. Written and electronic media, and contact with a nurse or doctor were effective sources of education on diabetes while "conversation with significant others", dietician or pharmacist were not effective. Nurse- or doctor-centred education appears to be an effective choice for future programmes to provide information to patients with diabetes.


Assuntos
Diabetes Mellitus/prevenção & controle , Educação de Pacientes como Assunto/normas , Atenção Primária à Saúde , Adulto , Comunicação , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/psicologia , Avaliação Educacional , Escolaridade , Correio Eletrônico , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Serviços de Informação , Masculino , Meios de Comunicação de Massa , Pessoa de Meia-Idade , Avaliação das Necessidades , Relações Enfermeiro-Paciente , Educação de Pacientes como Assunto/métodos , Relações Médico-Paciente , Prevalência , Inquéritos e Questionários , Materiais de Ensino , Emirados Árabes Unidos/epidemiologia , Saúde da População Urbana/estatística & dados numéricos
17.
Can J Infect Dis ; 12(1): 51-3, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18159317

RESUMO

Orbital myositis is a common cause of extraocular muscle enlargement. It is characterized by nonspecific inflammation of one or more extraocular muscles. Although often idiopathic in origin, orbital myositis has been associated with various noninfectious diseases. Several cases have also been reported as occurring after upper respiratory tract infections. The present report describes a case of orbital myositis together with subclinical sinusitis and its rapid resolution after antibiotic treatment. The literature on this clinical entity is also reviewed.

18.
(East. Mediterr. health j).
em Inglês | WHO IRIS | ID: who-119072

RESUMO

This study defined the baseline level of knowledge about diabetes and the perceived effectiveness of sources of diabetes information in an urban primary health care centre in Al-Ain. A validated questionnaire was administered to 300 randomly chosen adult patients with diabetes. Patient knowledge about diabetes was directly related to their level of general education. Written and electronic media, and contact with a nurse or doctor were effective sources of education on diabetes while "conversation with significant others", dietician or pharmacist were not effective. Nurse- or doctor-centred education appears to be an effective choice for future programmes to provide information to patients with diabetes


Assuntos
Escolaridade , Conhecimentos, Atitudes e Prática em Saúde , Meios de Comunicação de Massa , Relações Enfermeiro-Paciente , Educação de Pacientes como Assunto , Relações Médico-Paciente , Inquéritos e Questionários , Diabetes Mellitus
19.
J Palliat Med ; 3(1): 7-16, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-15859716

RESUMO

Teaching medical students to respond to needs of the dying represents an important challenge for medical educators. This article describes the goals and objectives that should be identified before medical schools can meet this challenge, as well as strategies that, when implemented, will provide students with the necessary knowledge, skills, and attitudes to meet the needs of the dying patients. The goals and objectives were identified through a modified group consensus process developed during Choice In Dying's 5-year project "Integrating Education on Care of the Dying into Medical Schools." The authors have diverse experiences and backgrounds and are actively involved in death and dying teaching at 11 medical schools. They conclude that after accepting the goals and objectives, key medical school faculty can work cooperatively to develop strategies to integrate them into the school's curriculum. Without first establishing a set of goals and objectives and developing evaluation methods, medical schools could miss their mark in fostering the student's ability to care for the dying.

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