RESUMO
Using exceptionally accurate measurements of the speed of sound in argon, we have made estimates of the difference between thermodynamic temperature, T, and the temperature estimated using the International Temperature Scale of 1990, T90, in the range 118 K to 303 K. Thermodynamic temperature was estimated using the technique of relative primary acoustic thermometry in the NPL-Cranfield combined microwave and acoustic resonator. Our values of (T-T90) agree well with most recent estimates, but because we have taken data at closely spaced temperature intervals, the data reveal previously unseen detail. Most strikingly, we see undulations in (T-T90) below 273.16 K, and the discontinuity in the slope of (T-T90) at 273.16 K appears to have the opposite sign to that previously reported.
RESUMO
The binding of double-stranded (ds) DNA to mica can be controlled through ion-exchanging the mica with divalent cations. Measurements of the end-to-end distance of linear DNA molecules discriminate whether the binding mechanism occurs through 2D surface equilibration or kinetic trapping. A range of linear dsDNA fragments have been used to investigate length dependences of binding. Mica, ion-exchanged with Ni(II) usually gives rise to kinetically trapped DNA molecules, however, short linear fragments (<800 bp) are seen to deviate from the expected behaviour. This indicates that ion-exchanged mica is heterogeneous, and contains patches or domains, separating different ionic species. These results correlate with imaging of dsDNA under aqueous buffer on Ni(II)-mica and indicate that binding domains are of the order of 100 nm in diameter. Shorter DNA fragments behave intermediate to the two extreme cases of 2D equilibration and kinetic trapping. Increasing the incubation time of Ni(II) on mica, from minutes to hours, brings the conformations of the shorter DNA fragments closer to the theoretical value for kinetic trapping, indicating that long timescale kinetics play a role in ion-exchange. X-ray photoelectron spectroscopy (XPS) was used to confirm that the relative abundance of Ni(II) ions on the mica surface increases with time. These findings can be used to enhance spatial control of binding of DNA to inorganic surfaces with a view to patterning high densities arrays.
Assuntos
Silicatos de Alumínio/química , Silicatos de Alumínio/metabolismo , DNA/química , DNA/metabolismo , Níquel/metabolismo , Sítios de Ligação , Troca Iônica , Cinética , Modelos Químicos , Conformação de Ácido Nucleico , Espectroscopia Fotoeletrônica , Fatores de TempoRESUMO
Problems associated with the use of alcohol and other drugs are among the most serious public health threats found on college and university campuses in the United States. The United States Department of Education's Fund for the Improvement of Postsecondary Education program has supported a nationwide effort among colleges and universities to address these problems. A key issue facing programs to prevent substance abuse is their prospect for survival as grant funding ends. In this article, the survival of one college-based alcohol and other drug prevention program and its move toward institutionalization in an extremely challenging fiscal environment are examined. The strategies described by the authors may be helpful for directors of other programs facing similar challenges.
Assuntos
Alcoolismo/prevenção & controle , Obtenção de Fundos/métodos , Serviços de Saúde para Estudantes/economia , Alcoolismo/reabilitação , California , Controle de Custos , Humanos , Organizações sem Fins Lucrativos , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Estados UnidosRESUMO
An educational program which emphasized the symmetrical use of back muscles was studied at a health care facility which had extremely high time lost injury rates due to back strains. Participants (N=180) were involved with half studying an educational program entitled "Back to Balance" with the remainder serving as controls. After 3 months, the controls studied the program. All subjects completed psychological tests, received cervical and lumbar paraspinal dynamic EMG evaluations four times (pre-and post-treatment, and after 3 and 12 months). Administrative indices (costs, incidence, and time lost injury rate) were obtained for the 3 years prior to the study and for the 1 year of the study. The 1-year results showed decreased pain, retained knowledge which was generalized to the home, and significantly improved symmetry of both sets of muscles. Administrative data revealed a 72% decrease in the time lost injury rate with reduced costs.
RESUMO
Fourteen patients with cirrhosis and subclinical hepatic encephalopathy were randomised to treatment with lactitol or lactulose for a 2-month period during which they were monitored clinically, by electroencephalography and by manually administered and computer-based psychometric testing. Following a washout period of 4-6 weeks patients were crossed-over to treatment with the alternative sugar for a similar period of monitoring. None of the patients showed evidence of overt hepatic encephalopathy and only one showed slowing of the electroencephalogram mean cycle frequency at the onset of the trial. However, significant impairment was observed in the group as a whole in the performance of all three manually administered psychometric tests and in four of the ten computer-based test variables. No changes were observed in clinical status or in electroencephalogram mean cycle frequency during treatment with either lactitol or lactulose. However, psychometric performance improved consistently, and to the same degree, during treatment with both sugars. Patients required a mean of 26 g (range 8-36) of lactitol and 25 ml (10-60) of lactulose to achieve two semi-soft stools per day. The majority of patients complained of flatulence during treatment with both sugars but this tended to resolve with continued treatment. Diarrhoea developed in a small number of patients during both treatment periods but this was invariably dose-related. Patients were equally divided in their preference for the two sugars. Patients with subclinical hepatic encephalopathy benefit from treatment with lactitol and lactulose in terms of their psychometric performance. The feasibility and benefits of long-term treatment for this condition need to be elucidated.
Assuntos
Dissacarídeos/uso terapêutico , Encefalopatia Hepática/tratamento farmacológico , Lactulose/uso terapêutico , Cirrose Hepática/complicações , Álcoois Açúcares/uso terapêutico , Ensaios Clínicos como Assunto , Eletroencefalografia , Feminino , Encefalopatia Hepática/etiologia , Humanos , Lactulose/efeitos adversos , Masculino , Testes Psicológicos , Distribuição Aleatória , Álcoois Açúcares/efeitos adversosRESUMO
The problem that needs to be addressed is the 58 percent immunity level among 2-year-olds in southeastern Idaho, a level created by the indifference or fear of parents. Southeastern Idaho has the highest birth rate of any region in the State, and this situation has created a large group of children susceptible to vaccine-preventable diseases. The mobile unit, which consists of a specially equipped motor home, allows easy access to immunizations for groups of children and their parents. A search of the computerized record system installed in the mobile unit can provide data on past immunizations for each registered child. The target audience for the mobile unit's visits is church groups because of the particular cultural demographics of this region. In 1987, the District Seven Health Department, a State- and county-funded agency, expects to increase the number of doses of vaccine given by 3,000 over the 19,953 given in 1986. The "Shots for Tots" program is unique in the State of Idaho. Its expansion may be anticipated as the unit becomes better known in the region. The alternative to using aggressive, innovative techniques to motivate people to become immunized is disease.