10,821 research outputs found
Uma breve história da teoria do Direito ocidental [1.ed.]
Divulgação dos SUMÁRIOS das obras recentemente incorporadas ao acervo da Biblioteca
Ministro Oscar Saraiva do STJ. Em respeito à lei de Direitos Autorais, não disponibilizamos a
obra na íntegra.Localização na estante: 340.12 K29
Flint at the Fort: Investigating Raw Material Scarcity and Locations of Lithic Activity at Monhantic Fort
The Monhantic Fort site on the Mashantucket Pequot reservation in southeastern Connecticut has yielded many insights into Pequot life in the late 17th century. This fortified village, occupied during King Philip\u27s War, has given archaeologists a glimpse of the domestic practices and organization of the people who lived within as well as details about how they engaged with military expeditions. In this thesis, I examine the lithic assemblage from Monhantic Fort. This assemblage, comprised of European flint employed to create tools like gunflints and strike-a-lights, can be used to investigate how the Pequots utilized new stone tool technologies and negotiated these technologies with pre-contact practices of lithic tool making. The first issue my thesis explores is raw material availability, as other sites have suggested that European flint was a scarce raw material in 17th century New England. The second issue concerns the retention of pre-contact Native practices of lithic production and maintenance. By analyzing the flakes and debitage recovered from different areas at the fort, one can see whether or not the Mashantucket Pequot had adopted specialization in production and maintenance of stone tools and where these activities were taking place. The evidence from both the artifacts and the documentary record demonstrates that raw material availability was not a problem for the Mashantucket Pequot living at the fort. It also shows that production and maintenance were not specialized activities, but that some households did have a more heavy focus on lithics
Cardiovascular consequences of cortisol excess
Cushing's syndrome is a consequence of primary or, more commonly, secondary oversecretion of cortisol. Cardiovascular disease is the major cause of morbidity and mortality in Cushing's syndrome, and excess risk remains even in effectively treated patients. The cardiovascular consequences of cortisol excess are protean and include, inter alia, elevation of blood pressure, truncal obesity, hyperinsulinemia, hyperglycemia, insulin resistance, and dyslipidemia. This review analyses the relationship of cortisol excess, both locally and at tissue level, to these cardiovascular risk factors, and to putative mechanisms for hypertension. Previous studies have examined correlations between cortisol, blood pressure, and other parameters in the general population and in Cushing's syndrome. This review also details changes induced by short-term cortisol administration in normotensive healthy men
Lactate Threshold
The purpose of this paper is to review the delicate metabolic balance an endurance athlete must maintain to achieve a desirable performance. The optimum pace is ultimately determined by the athlete\u27s ability to deliver large volumes of oxygen to the working muscles while simultaneously preventing excessive lactate accumulation in the tissues and blood.
Lactic acid has been associated with fatigue for nearly 80 years. This anaerobic metabolic by-product plays an important role in fatigue; however, many of the accusations concerning lactate\u27s role in causing fatigue are unfounded or exaggerated. Its negative reputation is the result of an inadequate understanding of lactate kinetics during exercise.
Lactic acid is a naturally occurring product of anaerobic metabolism. It is not bad or an undesirable substance; in fact, it is useful as an energy source, as a temporary pyruvate reservoir and as a means of preventing the body\u27s pH from falling to dangerously low levels.
The lactate threshold is defined as the highest metabolic rate obtainable while keeping the blood lactate at a steady state. At this level of intensity, the body is clearing lactate as rapidly as it is produced. Should the intensity increase beyond this critical point, lactate production exceeds removal rate causing a rapid increase in lactate accumulation.
For athletes to reach their greatest endurance potential, they must train their bodies to process lactate efficiently. This fine tuning allows them to compete at the highest possible intensity while maintaining relatively low concentrations of lactic acid
Observing mergers of non-spinning black-hole binaries
Advances in the field of numerical relativity now make it possible to
calculate the final, most powerful merger phase of binary black-hole
coalescence for generic binaries. The state of the art has advanced well beyond
the equal-mass case into the unequal-mass and spinning regions of parameter
space. We present a study of the nonspinning portion of parameter space,
primarily using an analytic waveform model tuned to available numerical data,
with an emphasis on observational implications. We investigate the impact of
varied mass ratio on merger signal-to-noise ratios (SNRs) for several
detectors, and compare our results with expectations from the test-mass limit.
We note a striking similarity of the waveform phasing of the merger waveform
across the available mass ratios. Motivated by this, we calculate the match
between our 1:1 (equal mass) and 4:1 mass-ratio waveforms during the merger as
a function of location on the source sky, using a new formalism for the match
that accounts for higher harmonics. This is an indicator of the amount of
degeneracy in mass ratio for mergers of moderate-mass-ratio systems.Comment: 13 pages, 11 figures, submitted to Phys. Rev.
Quantifying the Tibiofemoral Joint Space Using X-ray Tomosynthesis
Purpose: Digital x-ray tomosynthesis (DTS) has the potential to provide 3D information about the knee joint in a load-bearing posture, which may improve diagnosis and monitoring of knee osteoarthritis compared with projection radiography, the current standard of care. Manually quantifying and visualizing the joint space width (JSW) from 3D tomosynthesis datasets may be challenging. This work developed a semiautomated algorithm for quantifying the 3D tibiofemoral JSW from reconstructed DTS images. The algorithm was validated through anthropomorphic phantom experiments and applied to three clinical datasets. Methods: A user-selected volume of interest within the reconstructed DTS volume was enhanced with 1D multiscale gradient kernels. The edge-enhanced volumes were divided by polarity into tibial and femoral edge maps and combined across kernel scales. A 2D connected components algorithm was performed to determine candidate tibial and femoral edges. A 2D joint space width map (JSW) was constructed to represent the 3D tibiofemoral joint space. To quantify the algorithm accuracy, an adjustable knee phantom was constructed, and eleven posterior–anterior (PA) and lateral DTS scans were acquired with the medial minimum JSW of the phantom set to 0–5 mm in 0.5 mm increments (VolumeRadTM, GE Healthcare, Chalfont St. Giles, United Kingdom). The accuracy of the algorithm was quantified by comparing the minimum JSW in a region of interest in the medial compartment of the JSW map to the measured phantom setting for each trial. In addition, the algorithm was applied to DTS scans of a static knee phantom and the JSW map compared to values estimated from a manually segmented computed tomography (CT) dataset. The algorithm was also applied to three clinical DTS datasets of osteoarthritic patients. Results: The algorithm segmented the JSW and generated a JSW map for all phantom and clinical datasets. For the adjustable phantom, the estimated minimum JSW values were plotted against the measured values for all trials. A linear fit estimated a slope of 0.887 (R2¼0.962) and a mean error across all trials of 0.34 mm for the PA phantom data. The estimated minimum JSW values for the lateral adjustable phantom acquisitions were found to have low correlation to the measured values (R2¼0.377), with a mean error of 2.13 mm. The error in the lateral adjustable-phantom datasets appeared to be caused by artifacts due to unrealistic features in the phantom bones. JSW maps generated by DTS and CT varied by a mean of 0.6 mm and 0.8 mm across the knee joint, for PA and lateral scans. The tibial and femoral edges were successfully segmented and JSW maps determined for PA and lateral clinical DTS datasets. Conclusions: A semiautomated method is presented for quantifying the 3D joint space in a 2D JSW map using tomosynthesis images. The proposed algorithm quantified the JSW across the knee joint to sub-millimeter accuracy for PA tomosynthesis acquisitions. Overall, the results suggest that x-ray tomosynthesis may be beneficial for diagnosing and monitoring disease progression or treatment of osteoarthritis by providing quantitative images of JSW in the load-bearing knee
Functional characterization of a constitutively active kinase variant of Arabidopsis phototropin 1
Phototropins (phots) are plasma membrane-associated serine/threonine kinases that coordinate a range of processes linked to optimizing photosynthetic efficiency in plants. These photoreceptors contain two light-, oxygen- or voltage-sensing (LOV) domains within their N-terminus, with each binding one molecule of flavin mononucleotide (FMN) as a UV/blue light absorbing chromophore. Although phots contain two LOV domains, light-induced activation of the C-terminal kinase domain and subsequent receptor autophosphorylation is controlled primarily by the A′α-LOV2-Jα photosensory module. Mutations that disrupt interactions between the LOV2-core and its flanking helical segments can uncouple this mode of light regulation. Yet, the impact of these mutations on phot function in Arabidopsis has not been explored. Here, we report that histidine substitution of Arg-472 located within the A′α-helix of Arabidopsis phot1 to histidine results in constitutively activates kinas activity in vitro without affecting LOV2 photochemistry. Expression analysis of phot1 R472H in the phot-deficient mutant confirmed that it is autophosphorylated in darkness in vivo, but was unable to initiate phot1 signaling in the absence of light. Instead, we found that the phot1 R472H mutant is poorly functional under low-light conditions, but can restore phototropism, chloroplast accumulation, stomatal opening, and leaf positioning and expansion at higher light intensities. Our findings suggest that Arabidopsis can adapt to the elevated phosphorylation status of the phot1 R472H mutant by in part reducing its stability, whereas the activity the mutant under high-light conditions can be attributed to additional increases in LOV2-mediated photoreceptor autophosphorylation
Knowledge, Attitudes and Practices on Child Feeding and Care: Preliminary Insights from the Project on Linkages between Child Nutrition and Agricultural Growth
Food Consumption/Nutrition/Food Safety, Downloads May 2008-June 2009: 46,
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