1,399 research outputs found
Recommended from our members
Retrieving Decadal Climate Change from Satellite Radiance Observations-A 100-year CO2 Doubling OSSE Demonstration.
Preparing for climate change depends on the observation and prediction of decadal trends of the environmental variables, which have a direct impact on the sustainability of resources affecting the quality of life on our planet. The NASA Climate Absolute Radiance and Refractivity Observatory (CLARREO) mission is proposed to provide climate quality benchmark spectral radiance observations for the purpose of determining the decadal trends of climate variables, and validating and improving the long-range climate model forecasts needed to prepare for the changing climate of the Earth. The CLARREO will serve as an in-orbit, absolute, radiometric standard for the cross-calibration of hyperspectral radiance spectra observed by the international system of polar operational satellite sounding sensors. Here, we demonstrate that the resulting accurately cross-calibrated polar satellite global infrared spectral radiance trends (e.g., from the Metop IASI instrument considered here) can be interpreted in terms of temperature and water vapor profile trends. This demonstration is performed using atmospheric state data generated for a 100-year period from 2000-2099, produced by a numerical climate model prediction that was forced by the doubling of the global average atmospheric CO2 over the 100-year period. The vertical profiles and spatial distribution of temperature decadal trends were successfully diagnosed by applying a linear regression profile retrieval algorithm to the simulated hyperspectral radiance spectra for the 100-year period. These results indicate that it is possible to detect decadal trends in atmospheric climate variables from high accuracy all-sky satellite infrared radiance spectra using the linear regression retrieval technique
Preferências nutricionais entre adolescentes da classe média de Manaus, AM (Brazil)
INTRODUÇÃO: O Brasil tem sido considerado um País em transição nutricional em razão dos recentes aumentos na prevalência de obesidade e doenças crônicas na classe média, sendo importante identificar os fatores que influenciam as preferências nutricionais desse grupo. Foi realizado estudo com estudantes de classe média de um colégio secundário, particular, em Manaus, AM, Brasil. Com o objetivo de determinar a disponibilidade e a acessibilidade das merendas e analisar as atitudes e preferências dos estudantes e a influência de vários fatores na escolha de merendas nutritivas. MÉTODOS: O estudo incluiu quatros fases: (a) discusão em um grupo de especialistas em nutrição sobre a disponibilidade e acessibilidade das merendas em Manaus; (b) inquérito junto a um grupo dos adolescentes (n=63) sobre suas preferências e hábitos nutricionais; (c) inquérito junto a supermercados selecionado para identificar a disponibilidade e acessibilidade das merendas preferidas; (d) um grupo acompanhado de uma subamostra dos adolescentes (n=55) para identificar a preferências e atitudes sobre o custo e disponibilidade das merendas. RESULTADOS: Foi constatado que os estudantes possuíam condições financeiras para comprar merendas e que as merendas nutritivas não custam mais do que as não nutritivas. A preferência dos adolescentes foi por merendas não nutritivas. Os fatores que, principalmente, influenciam na escolha originam-se da família e da televisão. CONCLUSÃO: As implicações para futuras pesquisas e programas nutricionais são discutidos, recomendando-se campanha de educação nutricional para famílias, visto a importância desta na escolha de merendas entre esses adolescentes.INTRODUCTION: Brazil has been called a nation in nutrition transitional because of recent increases in the prevalence of obesity and related chronic diseases. With overweight conditions already prevalent among middle-income populations, there exists a need to identify factors that influence nutrition behavior within this group. OBJECTIVE: To address this subject, a research study was implemented among middle-class adolescents attending a large private secondary school in Manaus, Amazonas, Brazil. The study determined the availability and accessibility of snack foods as well as subjects’ attitudes and preferences towards, and the influence of family and friends on healthy (high-nutrient density) snack choices. METHODS: The 4-stage process included: (a) a nutrition expert focus group discussion that reported local nutrition problems in general and factors related to adolescent nutrition, (b) an adolescent pilot survey (n=63) that solicited information about snacking preferences and habits as well as resources for nutrition information and snack money; (c) a survey of various area food market sources to determine the availability and accessibility of high nutrient density snacks; and (d) a follow-up adolescent survey (n=55) that measured snack food preferences and perceptions about their cost and availability. RESULTS: Results included the finding that, although affordable high nutrient density snacks were available, preferences for low nutrient density snacks prevailed. The adolescents were reportedly more likely to be influenced by and obtain nutrition information from family members than friends. CONCLUSION: From study results it is apparent that a focus on food availability will not automatically result in proper nutritional practices among adolescents. This fact and the parental influence detected are evidence of a need to involve adolescents and their parents in nutrition education campaigns to improve adolescent snack food choices
Safety, tolerability, and efficacy of fixed combination therapy with dorzolamide hydrochloride 2% and timolol maleate 0.5% in glaucoma and ocular hypertension.
Glaucoma is a collection of diseases characterized by multifactorial progressive changes leading to visual field loss and optic neuropathy most frequently due to elevated intraocular pressure (IOP). The goal of treatment is the lowering of the IOP to prevent additional optic nerve damage. Treatment usually begins with topical pharmacological agents as monotherapy, progresses to combination therapy with agents from up to 4 different classes of IOP-lowering medications, and then proceeds to laser or incisional surgical modalities for refractory cases. The fixed combination therapy with the carbonic anhydrase inhibitor dorzolamide hydrochloride 2% and the beta blocker timolol maleate 0.5% is now available in a generic formulation for the treatment of patients who have not responded sufficiently to monotherapy with beta adrenergic blockers. In pre- and postmarketing clinical studies, the fixed combination dorzolamide-timolol has been shown to be safe and efficacious, and well tolerated by patients. The fixed combination dorzolamide-timolol is convenient for patients, reduces their dosing regimen with the goal of increasing their compliance, reduces the effects of washout when instilling multiple drops, and reduces the preservative burden by reducing the number of drops administered per day
Interferon-Γ inhibits DNA synthesis and insulin-like growth factor-II expression in human neuroblastoma cells
Interferon-Γ (IFN-Γ) is known to be an antiproliferative, differentiation agent in many cell types, including neuroblastoma. In this study, we determined the effects of IFN-Γ on cellular growth and expression of insulin-like growth factor II (IGF-II) and IGF receptors in the human neuroblastoma cell line SH-SY5Y. Incubation of SH-SY5Y cells in IFN-Γ (20–100 U/ml) induced the formation of long neuritic processes. IFN-Γ treatment also induced decreases in [ 3 H]TdR incorporation, as well as serum-dependent changes in cell number. Treatment with IFN-Γ reduced cell number 33% in the presence of serum but had no effect on cell number in the absence of serum. IGF-II mRNA content was 60% inhibited by IFN-Γ, and was not serum dependent. The concentration of immunoreactive IGF-II in SH-SY5Y conditioned medium was also reduced in the presence of IFN-Γ, to less than half of control levels. In contrast, type I IGF receptor mRNA content was increased more than three-fold after treatment with IFN-Γ and serum. Co-incubation in IFN-Γ (20–100 U/ml) and IGF-II on (3–10 nM) prevented the inhibitory effects of IFN-Γ on [ 3 H]TdR ncorporation in serum-free media. Our results suggest that IFN-Γ may inhibit DNA synthesis and cell growth by interfering with an IGF-II/type I IGF receptor autocrine growth or survival mechanism.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/50226/1/490340502_ftp.pd
Vicarious Experience Affects Patients' Treatment Preferences for Depression
Depression is common in primary care but often under-treated. Personal experiences with depression can affect adherence to therapy, but the effect of vicarious experience is unstudied. We sought to evaluate the association between a patient's vicarious experiences with depression (those of friends or family) and treatment preferences for depressive symptoms.We sampled 1054 English and/or Spanish speaking adult subjects from July through December 2008, randomly selected from the 2008 California Behavioral Risk Factor Survey System, regarding depressive symptoms and treatment preferences. We then constructed a unidimensional scale using item analysis that reflects attitudes about antidepressant pharmacotherapy. This became the dependent variable in linear regression analyses to examine the association between vicarious experiences and treatment preferences for depressive symptoms.Our sample was 68% female, 91% white, and 13% Hispanic. Age ranged from 18-94 years. Mean PHQ-9 score was 4.3; 14.5% of respondents had a PHQ-9 score >9.0, consistent with active depressive symptoms. Analyses controlling for current depression symptoms and socio-demographic factors found that in patients both with (coefficient 1.08, p = 0.03) and without (coefficient 0.77, p = 0.03) a personal history of depression, having a vicarious experience (family and friend, respectively) with depression is associated with a more favorable attitude towards antidepressant medications.Patients with vicarious experiences of depression express more acceptance of pharmacotherapy. Conversely, patients lacking vicarious experiences of depression have more negative attitudes towards antidepressants. When discussing treatment with patients, clinicians should inquire about vicarious experiences of depression. This information may identify patients at greater risk for non-adherence and lead to more tailored patient-specific education about treatment
National Institute of Neurological Disorders and Stroke (NINDS): Advances in understanding and treating neuropathy, 24–25 October 2006; Bethesda, Maryland
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75348/1/j.1529-8027.2008.00154.x.pd
Interactions between respiratory oscillators in adult rats
Breathing in mammals is hypothesized to result from the interaction of two distinct oscillators: the preBötzinger Complex (preBötC) driving inspiration and the lateral parafacial region (pFL) driving active expiration. To understand the interactions between these oscillators, we independently altered their excitability in spontaneously breathing vagotomized urethane-anesthetized adult rats. Hyperpolarizing preBötC neurons decreased inspiratory activity and initiated active expiration, ultimately progressing to apnea, i.e., cessation of both inspiration and active expiration. Depolarizing pFL neurons produced active expiration at rest, but not when inspiratory activity was suppressed by hyperpolarizing preBötC neurons. We conclude that in anesthetized adult rats active expiration is driven by the pFL but requires an additional form of network excitation, i.e., ongoing rhythmic preBötC activity sufficient to drive inspiratory motor output or increased chemosensory drive. The organization of this coupled oscillator system, which is essential for life, may have implications for other neural networks that contain multiple rhythm/pattern generators
Randomized placebo-controlled trial of amlodipine in vasospastic angina
AbstractObjectives. This study was designed to assess the efficacy and safety of amlodipine, a long-acting calcium channel blocker, in patients with vasospastic angina.Background. Previous studies have established the value of short-acting calcium channel blockers in the treatment of coronary spasm.Methods. Fifty-two patients with well documented vasospastic angina were entered into the present study. After a single-blind placebo run-in period, patients were randomized (in a double-blind protocol) to receive either amlodipine (10 mg) or placebo every morning for 4 weeks. Twenty-four patients received amlodipine and 28 received placebo. All patients were given diaries in which to record both the frequency, severity, duration and circumstances of anginal episodes and their intake of sublingual nitroglycerin tablets.Results. The rate of anginal episodes decreased significantly (p = 0.009) with amlodipine treatment compared with placebo and the intake of nitroglycerin tablets showed a similar trend. Peripheral edema was the only adverse event seen more frequently in amlodipine-treated patients. No patient was withdrawn from the double-blind phase of the study because of an adverse event. Patients who completed the double-blind phase as responders to amlodipine or as nonresponders to placebo were offered the option of receiving amlodipine in a long-term, open label extension phase. During the extension, the daily dose of amlodipine was adjusted to 5 or 15 mg if needed and the rate of both anginal episodes and nitroglycerin tablet consumption showed statistically significant decreases between baseline and final assessment.Conclusion. This study suggests that amlodipine given once daily is efficacious and safe in the treatment of vasospastic angina
Synthesis, Structure, and Reactivity of a Rhenium Oxo-Vinylalkylidene Complex
The reaction of 3 equiv of KOC(CF_3)_2Me with ReOCl_3(PPh_3)_2 in dichloromethane, followed by recrystallization from hexanes/THF, gives ReO[OC(CF_3)_2Me]_3(THF)_2( 1) in 35 7% yield. An
X-ray diffraction study of 1 (monoclinic, P2_1/n, a = 10.010(3) Å, b = 29.247(6) Å, c = 10.800(3) Å, β = 117.09(1)', Z = 4) reveals a facial arrangement of the three alkoxide ligands around the metal center in a distorted octahedron. The ligand environment in 1 is quite crowded, as evidenced by an elongated Re-O bond between rhenium and one of the THF ligands. The reaction of 3,3-diphenylcyclopropene with 1 in dichloromethane gives initially a mixture of two isomeric rhenium oxo-vinylalkylidene complexes, of which the isomer syn,mer-ReO[C(H)-CH=CPh_2] [OC(CF3)2Me]3(THF) (2b) was isolated in 87% yield. An X-ray diffraction study of 2b (triclinic, P1^(bar), a = 10.459(3) Å, b = 10.913(3) Å, c = 21.308(6) Å, α = 91.16(3)°,β = 102.05-(2)°, γ = 117.98(2)°, 2 = 2) supports a pseudooctahedral structure with mutually trans vinylalkylidene and THF ligands. Complex 2b does not react readily with internal or terminal olefins; however, the addition of GaBr_3 (1 equiv) to 2b yields moderately active catalyst(s) that metathesize cis-2-pentene at ~6.7 turnovers min^(-1). No propagating alkylidene species are observed during the metathesis reaction
- …