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1.
J Synchrotron Radiat ; 22(4): 908-24, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26134794

RESUMO

A detailed description is presented of the Extreme Conditions Beamline P02.2 for micro X-ray diffraction studies of matter at simultaneous high pressure and high/low temperatures at PETRA III, in Hamburg, Germany. This includes performance of the X-ray optics and instrumental resolution as well as an overview of the different sample environments available for high-pressure studies in the diamond anvil cell. Particularly emphasized are the high-brilliance and high-energy X-ray diffraction capabilities of the beamline in conjunction with the use of fast area detectors to conduct time-resolved compression studies in the millisecond time regime. Finally, the current capability of the Extreme Conditions Science Infrastructure to support high-pressure research at the Extreme Conditions Beamline and other PETRA III beamlines is described.

2.
Phys Rev Lett ; 111(11): 114801, 2013 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-24074093

RESUMO

Initiating the gain process in a free-electron laser (FEL) from an external highly coherent source of radiation is a promising way to improve the pulse properties such as temporal coherence and synchronization performance in time-resolved pump-probe experiments at FEL facilities, but this so-called "seeding" suffers from the lack of adequate sources at short wavelengths. We report on the first successful seeding at a wavelength as short as 38.2 nm, resulting in GW-level, coherent FEL radiation pulses at this wavelength as well as significant second harmonic emission at 19.1 nm. The external seed pulses are about 1 order of magnitude shorter compared to previous experiments allowing an ultimate time resolution for the investigation of dynamic processes enabling breakthroughs in ultrafast science with FELs. The seeding pulse is the 21st harmonic of an 800-nm, 15-fs (rms) laser pulse generated in an argon medium. Methods for finding the overlap of seed pulses with electron bunches in spatial, longitudinal, and spectral dimensions are discussed and results are presented. The experiment was conducted at FLASH, the FEL user facility at DESY in Hamburg, Germany.

3.
Nutr Metab Cardiovasc Dis ; 23(3): 177-82, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22209739

RESUMO

BACKGROUND AND AIM: Studies of adults and children with celiac disease (CD) performed mostly in tertiary care centers have reported an increased risk of overweight during gluten-free diet (GFD). We measured body mass index (BMI) of CD children followed by family pediatricians in order to estimate prevalence of underweight and overweight at diagnosis and to describe BMI changes during GFD. METHODS AND RESULTS: We compared 150 CD children (age range 2-16 yrs) under GFD from a median (IQR) time of 4.4 (4.2) years with 288 healthy children matched for gender and age. We also evaluated retrospectively BMI changes between CD diagnosis and the current evaluation. The median (IQR) BMI of CD patients was significantly lower than that of controls [-0.38 (1.46) vs. 0.09 (1.18) SDS, p < 0.0001, Italian reference data]. Using the International Obesity Task Force classifications, CD children were less frequently overweight or obese (12% vs. 23.3%, p = 0.014) and more frequently underweight (16% vs. 4.5%, p < 0.001) than controls. During GFD, there was a marked decrease of number of underweight subjects (13 vs. 27) and a minimal increase of number of overweight subjects (9 vs. 6) (p < 0.001). CONCLUSIONS: The frequency of overweight and obesity at diagnosis of CD and during GFD in children followed by family pediatricians is substantially lower than that reported in tertiary care centers. On the other hand, the high frequency of underweight at diagnosis confirms the need of careful personalized nutritional management.


Assuntos
Índice de Massa Corporal , Doença Celíaca/dietoterapia , Dieta Livre de Glúten , Magreza/etiologia , Adolescente , Composição Corporal , Doença Celíaca/complicações , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Obesidade/etiologia , Pediatria/estatística & dados numéricos , Prevalência , Estudos Retrospectivos , Centros de Atenção Terciária/estatística & dados numéricos
4.
Vet Rec ; 146(12): 338-41, 2000 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-10777040

RESUMO

Three management programmes to improve the reproductive performance of a dairy herd were compared in a prospective controlled field study on one commercial farm. A total of 542 cows were examined for endometritis 22 to 28 days postpartum and assigned to one of three treatment groups: in group 1 the cows with signs of endometritis were treated with an intrauterine infusion of 100 ml of a 2 per cent polycondensated m-cresolsulphuric acid formaldehyde solution; in group 2 the cows with signs of endometritis were treated with an intrauterine infusion of 125 ml of a 20 per cent eucalyptus compositum solution; and in group 3 all the cows were injected intramuscularly with 0.75 mg of tiaprost, an analogue of prostaglandin F2alpha (PGF2alpha) at two-week intervals, starting on day 43, until they were inseminated. Thirty-four per cent of the cows showed signs of endometritis. In group 3, oestrus detection efficiency was significantly higher than in groups 1 and 2 (P<0.05), the interval to first service was shorter, and the cows had fewer days open than the cows in groups 1 and 2 (P<0.05). The results indicate that management programmes based on the strategic use of PGF2alpha are an effective alternative to traditional programmes based on rectal palpations and intrauterine infusions to control endometritis at a herd level.


Assuntos
Doenças dos Bovinos/prevenção & controle , Endometrite/prevenção & controle , Endometrite/veterinária , Reprodução , Criação de Animais Domésticos , Animais , Bovinos , Cresóis/uso terapêutico , Indústria de Laticínios , Endometrite/complicações , Eucalyptus/uso terapêutico , Feminino , Luteolíticos/uso terapêutico , Fitoterapia , Plantas Medicinais , Prostaglandinas F Sintéticas/uso terapêutico , Tiofenos/uso terapêutico , Resultado do Tratamento
11.
Appl Occup Environ Hyg ; 16(2): 228-32, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11217715

RESUMO

In the notification procedure for new substances, the need to conduct further toxicity tests may arise if the outcome of a qualitative or quantitative risk assessment indicates relevant risks. Sometimes a quantitative assessment is not possible (e.g., if a no observed adverse effect level [NOAEL] is not available). A different approach is required for such substances. An approach based on the correlation of the classification of the substance (the possible outcome of testing) with the assumed tolerable exposure levels is presented here. It relates to the hazard band model developed by the Health and Safety Executive (HSE) of the United Kingdom. To aid decision-making, the assumed tolerable exposure level is compared with the estimated workplace exposure level by means of calculating the quotient of these two figures. The quotient is called the assumed margin of safety (AMOS). A quotient higher than 1 means that testing may be deferred. The approach is described for a powdery substance used as a pigment in the coloration of plastics and rubber. Depending on the exposure situation, the need for further testing to determine the repeated dose toxicity of the substance is discussed.


Assuntos
Técnicas de Apoio para a Decisão , Exposição Ocupacional/análise , Gestão da Segurança/métodos , Humanos , Concentração Máxima Permitida , Modelos Teóricos , Medição de Risco/métodos
12.
Ann Occup Hyg ; 47(7): 571-5, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14530183

RESUMO

In 1998 the Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) launched the Convention Project on Chemical Safety in developing countries. The project aims to support developing countries in the implementation of the Rotterdam and Stockholm Conventions, create human resources and institutional capacities and to demonstrate via pilot measures how chemical safety in the partner countries can be improved and sustainably implemented in line with international standards. With this objective the development of a Chemical Management Guide (CM Guide) for small and medium-sized enterprises in developing countries has been initiated. The guide describes a step-by-step approach which is based on identifying 'hot-spots' as a first step, and making a chemical inventory as a second step. The third step is the continuous improvement of chemical management. In total, there are six tools that aim to support the chemical management process: basic concepts for risk assessment; description of control approaches; using material safety data sheets (MSDSs); risk phrases for hazardous substances; safety phrases for hazardous substances; symbols used for labelling hazardous substances. In the course of the test-implementation of the CM Guide in Indonesia, it was found that MSDSs were not available in most of the smaller companies. In contrast, medium-sized and larger companies do have more MSDSs available. It was also found that the way to engage the minds of company owners and managers is with economic arguments related to the loss, waste and expiry of materials, and quality standards expected from importing countries.


Assuntos
Países em Desenvolvimento , Substâncias Perigosas/toxicidade , Exposição Ocupacional/prevenção & controle , Medição de Risco/métodos , Humanos , Indonésia , Saúde Ocupacional , Projetos Piloto
13.
Ann Occup Hyg ; 47(7): 557-69, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14530182

RESUMO

This paper presents an in-house BAuA study on the evaluation of the COSHH Essentials exposure predictive model. External validation is based on measurement data obtained in BAuA field studies performed in various industries, e.g. printing industry and textile industry. In addition, measurement data and information on industrial hygiene provided by the chemical industry within the framework of the Existing Substances Risk Assessment programme are used. Although the evaluated exposure data cover a wide variety of activities and workplace scenarios, there is still a considerable lack of appropriate exposure data, especially for the more stringent control strategies. It was found that the level of agreement between the measurements for solid substances (powders, dusts) and the predicted ranges is reasonably good. The situation is in part different for liquids. In workplaces where organic solvents are used in litre quantities, exposure levels are within the predicted ranges or are often lower. For small-scale uses of liquids (millilitre scale), e.g. in carpenters' workshops, there were indications that the exposure levels can exceed the predicted ranges. However, it must be noted that the database is rather small.


Assuntos
Substâncias Perigosas/toxicidade , Modelos Teóricos , Exposição Ocupacional/prevenção & controle , Medição de Risco/métodos , Substâncias Perigosas/administração & dosagem , Humanos , Saúde Ocupacional
14.
Pediatr Nephrol ; 8(6): 719-23, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7696112

RESUMO

The effect of intramuscular calcitriol was evaluated in five children (aged 1-16 years) with severe chronic renal failure and hyperparathyroidism [range of intact parathyroid hormone (PTH) 400-1,200 pg/ml]. All five children had been on oral calcitriol or 1 alpha-hydroxyvitamin D3 treatment (5-20 ng/kg per day), but an adequate, efficacious dosage could not be achieved since any attempt of increasing the dosage resulted in severe hypercalcaemia (> 2.9 mmol/l). Intramuscular calcitriol was given three times weekly for 5 months at an initial dosage of 65-70 ng/kg to all but one patient who received 100 ng/kg. In the first three patients, treatment resulted in an 86%-98% fall in serum PTH compared with baseline levels and serum calcium never exceeded 2.65 mmol/l, except for one episode of hypercalcaemia in one patient. In the last two patients, serum calcium rose above normal limits, thus calcitriol had to be discontinued several times and then restarted at a lower dosage (40 ng/kg); PTH fell by 61% and 73%, respectively, compared with basal values. All patients had very low pre-treatment levels of serum 1,25-dihydroxyvitamin D3 (5-15 pg/ml) which were normalized (35-56 pg/ml) by the intramuscular calcitriol-treatment. Serum phosphorus and magnesium did not vary in any of the five patients. No side effects were observed at the injection site. Intramuscular calcitriol seems a useful therapeutic option for patients with severe hyperparathyroidism associated with a high serum calcium level when treated with conventional oral calcitriol.


Assuntos
Calcitriol/administração & dosagem , Hipercalcemia/tratamento farmacológico , Hiperparatireoidismo Secundário/tratamento farmacológico , Uremia/complicações , Administração Oral , Adolescente , Calcitriol/sangue , Cálcio/sangue , Cálcio/urina , Criança , Pré-Escolar , Doença Crônica , Creatinina/sangue , Creatinina/urina , Feminino , Humanos , Hipercalcemia/etiologia , Hiperparatireoidismo Secundário/etiologia , Técnicas Imunoenzimáticas , Lactente , Injeções Intramusculares , Masculino , Hormônio Paratireóideo/sangue , Hormônio Paratireóideo/metabolismo , Fósforo/sangue , Uremia/metabolismo
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