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Clear sky emittance models provide critical information for the determination of downwelling longwave irradiance at the Earth's surface. This study updates existing calculations which relate clear sky longwave emissivity with the main (and most variable) greenhouse gas in the atmosphere, water vapor. Impacts of station elevation and data quality control are quantified. Empirical results are used to validate highly resolved spectral models, and the resultant simplified calculates provide accurate estimations of clear sky emissivity without the need for extensive computation. Results show that correlation coefficients are mostly robust to nuanced data processing choices when regressed from sufficiently large data sets (≥104 samples) with the exceptions of altitude adjustment and measurement bias corrections. The empirical results from this study are compared to results from other leading empirical, physics‐based, and hybridized phenomenological models. Correlations for effective clear sky emissivity, transmissivity and optical depth are provided, based on parameterized line‐by‐line (LBL) model results, for the broadband 0–2,500 cm−1 and for seven wavenumber wideband of interest. Results for the (b3) wideband 580–750 cm−1 are particularly relevant because of its disaggregated and combined carbon dioxide‐water vapor contributions. The broadband effective optical depth (δ) of water vapor is found to be δH2O=0.628+54.756pw ${\delta }_{{\mathrm{H}}_{2}\mathrm{O}}\,=\,0.628\,+\,54.756\,\,{p}_{w}$, where pw is the dimensionless partial pressure of water vapor at the surface. Equivalently, the broadband effective optical depth of carbon dioxide in the presence of water vapor is found to be δCO2=0.269−10.229pw ${\delta }_{{\text{CO}}_{2}}=0.269-10.229\,{p}_{w}$. Processed training data sets are provided as supplementary content for comparative studies. Plain Language Summary: Greenhouse gasses affect how Earth's atmosphere absorbs and re‐emits heat to the Earth's surface. This absorption and re‐emission can be studied with models over the entire infrared spectrum (broadband) and over discrete sections of the spectrum (spectral wideband) that assume a cloudless state of the atmosphere. This work builds on previous models and suggests new ways to handle data from ground observations to prepare well‐formed data sets (called training sets) to which the models are fitted. Results show that the numerical coefficients found with these training sets are robust when corrected for relevant factors such as altitude or scale height. Additionally, effective radiative atmospheric properties like emissivity, transmissivity, and optical depth are modeled for individual gasses in the atmosphere (in the cloudless state) using a combination of both physical models and ground data. These properties are important for understanding the effect greenhouse gasses have on surface temperature, net radiation, and other factors that impact planetary climate. Key Points: A clear methodology to parameterize clear sky emissivity is provided with context for the sensitivity of results to data preparationThe proposed model shows good agreement with existing empirical and physics‐based modelsBroadband and spectral wideband correlations for the optical depth values of individual atmospheric constituents are proposed [ABSTRACT FROM AUTHOR]

We propose a framework for modeling the temperature-dependent infrared optical and radiative properties of metals exhibiting nonideal free-carrier dynamics. In order to do so, we derive a parsimonious model that possesses both multivariate (in temperature and wavelength) and single variate (in wavelength) components. The model is realized as the complex-valued relative permittivity and is applicable to optically smooth media. A procedure is outlined for regressing both components of the model under an appropriate set of physical constraints that preclude superfluous degrees of freedom. The procedure is demonstrated by applying the model to nickel, a transition metal of technical significance that possesses nontrivial valency. The resulting model yields practically accurate results for eight data sets spanning four separate studies, representing the approximate wavelength (λ) bandwidth between 1 and 16 μ m and the approximate temperature (T) range between 0 and 1400 K. The proposed model framework retains phase information and can, therefore, be directly interfaced with more complex Fresnel frameworks, such as those commonly used for modeling systematically or randomly roughened surfaces. [ABSTRACT FROM AUTHOR]

The objective of this study was to assess the acute effect of different intensities of whole body vibration (WBV) on muscle performance. 8 recreationally trained males were randomly subjected to one of 3 experimental conditions: (A) WBV 2 mm [45 Hz and 2 mm], (B) WBV 4 mm [45 Hz and 4 mm], and (C) no WBV. To assess PAP, the peak concentric torque of knee flexors and extensors was measured during a set of 3 unilateral knee flexor-extensions at 60 °/s− 1 in an isokinetic dynamometer. The power output and height during vertical jumps were also evaluated. These measurements were performed both before and after the experimental conditions and then compared. Comparing the knee flexion data from the conditions with and without WBV indicate that WBV potentiated the peak torque during unilateral knee flexion in the isokinetic test (p < 0.05). In addition, the power output (p = 0.01) and vertical height of jump (p = 0.03) were also potentiated by WBV. However, increasing the vibratory stimulus did not further potentiate the results. Thus, it is suggested that WBV be used before explosive events competition because WBV promotes post-activation potentiation. [ABSTRACT FROM AUTHOR]

The article discusses the results of an electrocardiographic study of 50 healthy Quarter Horses, ranging from six months to 28-years-old in age. The study showed that 32 percent of the subjects have sinus rhythm and sinus tachycardia rhythmus. There was no difference in heart rate with ages despite a reduction observed with growth in thoroughbred and Andalusian breeds.

The effects of blocking ventromedial hypothalamic nucleus (VMH) muscarinic cholinoceptors on cardiovascular responses were investigated in running rats. Animals were anesthetized with pentobarbital sodium and fitted with bilateral cannulae into the VMH. After recovering from surgery, the rats were familiarized to running on a treadmill. The animals then had a polyethylene catheter implanted into the left carotid artery to measure blood pressure. Tail skin temperature (Ttail), heart rate, and systolic, diastolic and mean arterial pressure were measured after bilateral injections of 0.2 μl of 5 x 10-9 mol methylatropine or 0.15 M NaCl solution into the hypothalamus. Cholinergic blockade of the VMH reduced time to fatigue by 31% and modified the temporal profile of cardiovascular and Ttail adjustments without altering their maximal responses. Mean arterial pressure peak was achieved earlier in methylatropine-treated rats, which also showed a 2-min delay in induction of tail skin vasodilation, suggesting a higher sympathetic tonus to peripheral vessels. In conclusion, muscarinic cholinoceptors within the VMH are involved in a neuronal pathway that controls exercise-induced cardiovascular adjustments. Furthermore, blocking of cholinergic transmission increases sympathetic outflow during the initial minutes of exercise, and this higher sympathetic activity may be responsible for the decreased performance. [ABSTRACT FROM AUTHOR]

This work advances our understanding of the drag force acting on a particle due to the oscillatory flow of a viscous fluid with finite Reynolds and Strouhal numbers. The drag force is is determined using the novel concept of variable order (VO) calculus, where the order of derivative can vary with the parameters and variables, according to the dynamics of the flow. Using the VO formulation we determine: (i) The region of validity of Tchen's equation for oscillatory flow, (ii) the region where the order of the derivative is fractional but constant, and (iii) the region where the strong non-linearity of the flow requires a variable order derivative to account for the increased complexity of the flow. [ABSTRACT FROM AUTHOR]

We report results of a series of detailed experiments designed to unveil the dynamics of a particle of radius a moving in high-frequency, low-Reynolds-number oscillatory flow. The fundamental parameters in the problem are the Strouhal (SI) and the particle Reynolds numbers (Rep), as well as the fluid-to-particle density ratio α. The experiments were designed to cover a range of Sl Rep from 0.015 to 5 while keeping Rep < 0.5 and Sl > 1. The primary objective of the experiments is to investigate stationary history effects associated with the Basset drag, which are maximized when the viscous time scale a2/ν is of the same order of the flow time scale $/Ω, where 9 is a geometrical factor for the sphere, ν is the kinematic viscosity and Ω is the angular frequency of the background flow. The theoretically determined behaviour of stationary history effects is confirmed unequivocally by the experiments, which also validate the fractional derivative behaviour (of order 1/2) of the history drag for the range of parameters under study. [ABSTRACT FROM AUTHOR]

We examine memory viscous effects on the motion of a particle in the vicinity of nodal points. The Basset history force has a fractional derivative dependence of order 3/2 on the particle displacement, and its contribution to the dynamics of acoustically forced particles is demonstrated for typical conditions occurring in acoustic separation devices. The inclusion of the Basset history force in the formulation has the net effect of changing the eigenfunctions of the problem from exponential to Mittag-Leffler functions, thus affecting the overall balance of forces considered. [ABSTRACT FROM AUTHOR]

Tungsten (W) is a valuable element with considerable industrial and economic importance that belongs to the European Union list of critical metals with a high supply risk. Therefore, the development of effective and new methods for W recovery is essential to ensure a sustainable supply. In the present study, the Sulfitobacter dubius W transport system TupABC was explored in order to demonstrate both its functionality in Escherichia coli cells and to construct a bioaccumulator (EcotupW). The complete gene cluster tupBCA or partial gene cluster tupBC were cloned in an expression vector and transformed into E. coli. Metal accumulation was evaluated when each construct strain was grown with three separate metal oxyanions (tungstate, molybdate or chromate). The specificity of the bioaccumulator was determined by competition assays using cells grown with mixed solutions of metal oxyanions (W/Mo and W/Cr). The results showed the relevance of the TupA protein in the TupABC transporter system to W-uptake and also allowed Mo and Cr accumulations, although with amounts 1.7 and 2.9-fold lower than W, respectively. To identify the importance of the valine residue in the accumulation efficiency of the VTTS motif, site-directed mutagenesis of tupA was performed. A mutant with a threonine residue, instead of the respective valine, confirmed that W was internalized by nearly double the amount compared to the native form. The findings indicated that cells carrying the native S. dubius TupABC system were great W-bioaccumulators and could be promising tools for W recovery. [ABSTRACT FROM AUTHOR]

Este artigo parte de idéias contidas em algumas obras de Foucault, levantando questões referentes à produção de verdades, a hegemonia da ciência positiva e aos binarismos presentes no mundo contemporâneo. Aponta, ainda, como o pensamento desse filósofo tem sido uma potente ferramenta, que tem possibilitado colocar em análise as crenças produzidas pelo pensamento platônico, ainda hoje dominante no Ocidente. A partir daí, coloca em discussão a divisão psicologia versus política, procurando pensar que efeitos têm sido produzidos por tal dicotomia cotidiana.

Pretende-se levantar como os meios de comunicação de massa são também responsáveis pela produção de modos hegemônicos de ser e de existir no mundo. Apresenta-se um rápido histórico do crescimento e expansão da mídia no Brasil e de sua centralização e controle. A seguir, através de como vêm funcionando os mass-media, apontam-se como vão sendo forjadas essas normas hegemônicas de se estar no mundo. Finaliza-se assinalando-se que, apesar desse poderio, há estratégias de resistência construindo, mesmo que local e provisoriamente, outros modos de vida, outros modos de existência.

We describe a physical framework for analyzing the spectral dynamics of a broad range of media. The framework is built on a variable-order calculus formalism that permits the description of temporally nonlocal behavior. Such emergent behavior is observed in the response of assorted complex media. The analytical features of the formalism are discussed and it is demonstrated how they correspond to the generalization of other well known theories for the description of nonlocal many-body effects. The framework is employed to analyze a set of spectroscopic data for the high-frequency dielectric response of a nanofluidic graphene dispersion and the midinfrared optical response of amorphous quartz silica. A practical application of the analysis is facilitated by a model definition that generalizes the semiclassical Lorentz theory to allow for nonlocal damping effects. The model is derived from a fractional order differential equation of motion. From the analysis, an estimated parametrization for the model structure is obtained. The fidelity of the analysis methodology is validated against optimized parametrizations in a multiobjective (optical and radiative) setting. The results demonstrate the utility of the analysis and indicate a specific well-defined region of nonlocality having a distinct fidelity that encompasses the entire Pareto front. This region is shown to be inaccessible to integer order descriptions of the mean field dynamics. [ABSTRACT FROM AUTHOR]

Abstract Background The aim of this study was to characterize the nutritional status of Xavante Indian children less than 10 years of age in Central Brazil and to evaluate the hypothesis of an association between child nutrition and socioeconomic differentiation in this population. Methods A cross-sectional study was conducted in July 2006 that included all children under the age of 10 from the Xavante village Pimentel Barbosa in Mato Grosso, Brazil. The data collected included weight, height, and sociodemographic information. Sociodemographic data were used to generate two indices ("income" and "wealth") and to determine the proportion of adults in each household. Descriptive analyses were performed for weight-for-age (W/A), height-for-age (H/A), and weight-for-height (W/H) using the NCHS and the WHO growth references. Univariate and multivariate analyses were conducted using H/A and W/A as a response variables. Results Of a total of 246 children under the age of ten residing in the village, 232 (94.3%) were evaluated. Following the NCHS reference, 5.6% of children under the age of ten presented low W/A and 14.7% presented low H/A. Among children under the age of five, deficit percentages for weight and height were 4.5% and 29.9%, respectively, following the WHO curves. Among children < 2 years of age, H/A index variability was found to be directly related to child's age and inversely related to the proportion of adults in the household. Maternal BMI was positively associated with growth for children from 2 to 4 years of age, explaining 11.5% of the z-score variability for the H/A index. For children 5 years of age and older, the wealth index and maternal height were positively associated with H/A. No significant associations were found using W/A as the dependent variable. Conclusion This study demonstrated that undernutrition, in particular linear growth deficit, is a notable health issue for Xavante children. These findings contrast with the nutritional profile observed among Brazilian children nationally, which is characterized by a sharp decline in child undernutrition in recent decades, even in the poorest regions of the country. This discrepancy calls attention to the persistent health disparities that exist between indigenous and non-indigenous people in Brazil.

Abstract Background This study evaluated the relationship between ulcerative colitis and obesity, which are both chronic diseases characterized by inflammation and increases in immune cells and pro-inflammatory cytokines. Methods Mice with chronic ulcerative colitis induced by 2 cycles of dextran sodium sulfate (DSS) in the first and fourth week of the experiment were fed a high-fat diet (HFD) to induce obesity by 8 weeks. The animals were divided into 4 groups (control, colitis, HFD and colitis + HFD). Results Obesity alone did not raise histopathology scores, but the combination of obesity and colitis worsened the scores in the colon compared to colitis group. Despite the reduction in weight gain, there was increased inflammatory infiltrate in both the colon and visceral adipose tissue of colitis + HFD mice due to increased infiltration of macrophages, neutrophils and lymphocytes. Intravital microscopy of VAT microvasculature showed an increase in leukocyte adhesion and rolling and overexpression of adhesion molecules compared to other groups. Moreover, circulating lymphocytes, monocytes and neutrophils in the spleen and cecal lymph nodes were increased in the colitis + HFD group. Conclusion Our results demonstrated the relationship between ulcerative colitis and obesity as aggravating factors for each disease, with increased inflammation in the colon and adipose tissue and systemic alterations observed in the spleen, lymph nodes and bloodstream.

Abstract Background Malaria constitutes a major cause of morbidity in the Brazilian Amazon where an estimated 6 million people are considered at high risk of transmission. Indigenous peoples in the Amazon are particularly vulnerable to potentially epidemic disease such as malaria; notwithstanding, very little is known about the epidemiology of malaria in Indian reservations of the region. The aim of this paper is to present a spatial analysis of malaria cases over a four-year time period (2003–2006) among indigenous peoples of the Brazilian State of Rondônia, southwestern Amazon, by using passive morbidity data (results from Giemsa-stained thick blood smears) gathered from the National Malaria Epidemiologic Surveillance System databank. Results A total of 4,160 cases of malaria were recorded in 14 Indian reserves in the State of Rondônia between 2003 and 2006. In six reservations no cases of malaria were reported in the period. Overall, P. vivax accounted for 76.18 of malaria cases reported in the indigenous population of Rondônia. The P. vivax/P. falciparum ratio for the period was 3.78. Two reserves accounted for over half of the cases reported for the total indigenous population in the period – Roosevelt and Pacaas Novas – with a total of 1,646 (39.57%) and 1,145 (27.52%) cases, respectively. Kernel mapping of malaria mean Annual Parasite Index – API according to indigenous reserves and environmental zones revealed a heterogeneous pattern of disease distribution, with one clear area of high risk of transmission comprising reservations of west Rondônia along the Guaporé-Madeira River basins, and another high risk area to the east, on the Roosevelt reserve. Conclusion By means of kernel mapping, it was shown that malaria risk varies widely between Indian reserves and environmental zones defined on the basis of predominant ecologic characteristics and land use patterns observed in the southwestern Brazilian Amazon. The geographical approach in this paper helped to determine where the greatest needs lie for more intensively focused malaria control activities in Indian reserves in the region. It also provided a reference to assess the effectiveness of control measures that have been put in place by Brazilian public health authorities.