1,563 research outputs found

    Heterozygosity and fitness in a California population of the labyrinth spider Metepeira ventura (Araneae, Araneidae).

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    The relationship between individual heterozygosity and characteristics likely to be associated with fitness was investigated in the labyrinth spider Metepeira ventura. Adult females and their egg sacs were collected at a coastal site in southern California, and three measures of bodily condition (carapace width, weight, residual index) and six measures of reproductive output (number of egg sacs, variation in egg number among sacs [coefficient of variation], total number of eggs, mean eggs/sac, mean eggs/sac divided by carapace width, mean eggs/sac divided by weight) were determined for each spider. The sample was polymorphic at three allozyme loci that were in Hardy-Weinberg equilibrium, and individual females were heterozygous at up to two of the three loci, forming three heterozygosity classes (0, 1, and 2). None of the bodily condition measures were significantly related to the number of heterozygous loci, while four of the reproductive output estimators (total number of eggs, mean eggs/sac, mean eggs/sac divided by carapace width, mean eggs/sac divided by weight) were significantly influenced by heterozygosity. In each significant case, values for class 2 females were less than those for class 0 and 1 females, whose values were usually more similar. Thus, while female bodily condition was comparable among classes, the most heterozygous females produced fewer total eggs and eggs per sac than their less heterozygous peers. The fact that females of M. ventura engage in a reproductive investment-number trade-off suggests that high-variability and low-variability females may be pursuing distinct reproductive strategies in the wild, with more heterozygous females being K-selected (smaller clutches, heavier eggs) and more homozygous females being r-selected (larger clutches, lighter eggs). Further investigation will be needed to assess more fully the fitness value of heterozygosity in M. ventura

    Perioperative standard oral nutrition supplements versus immunonutrition in patients undergoing colorectal resection in an Enhanced Recovery (ERAS) protocol

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    To compare immunonutrition versus standard high calorie nutrition in patients undergoing elective colorectal resection within an Enhanced Recovery After Surgery (ERAS) program. Despite progress in recent years in the surgical management of patients with colorectal cancer (ERAS programs), postoperative complications are frequent. Nutritional supplements enriched with immunonutrients have recently been introduced into clinical practice. However, the extent to which the combination of ERAS protocols and immunonutrition benefits patients undergoing colorectal cancer surgery is unknown. The SONVI study is a prospective, multicenter, randomized trial with 2 parallel treatment groups receiving either the study product (an immune-enhancing feed) or the control supplement (a hypercaloric hypernitrogenous supplement) for 7 days before colorectal resection and 5 days postoperatively. A total of 264 patients were randomized. At baseline, both groups were comparable in regards to age, sex, surgical risk, comorbidity, and analytical and nutritional parameters. The median length of the postoperative hospital stay was 5 days with no differences between the groups. A decrease in the total number of complications was observed in the immunonutrition group compared with the control group, primarily due to a significant decrease in infectious complications (23.8% vs. 10.7%, P=0.0007). Of the infectious complications, wound infection differed significantly between the groups (16.4% vs. 5.7%, P=0.0008). Other infectious complications were lower in the immunonutrition group but were not statistically significantly different. The implementation of ERAS protocols including immunonutrient-enriched supplements reduces the complications of patients undergoing colorectal resection

    Placas pleurales por inhalación de fibras de asbesto

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    Indexación: Scopus.Introduction: Asbestos fiber pleural plaque is characterized by lesions composed of fibrous tissue that are located in the parietal pleura. They usually appear in up to 3 to 58% of workers who were exposed to asbestos fiber, and 0.5 to 8% in the general population. The objective of this article is to present a case report of a patient whose chest x-ray showed pleural changes associated with exposure to asbestos fibers. Case report: A 49-year-old male patient, construction worker with a history of exposure to asbestos fibers, underwent a chest x-ray performed according to International Labor Organization (ILO) standards, which revealed focal pleural changes. Subsequently, the presence of pleural plaques was confirmed by computed tomography (CT) scan of the chest. Discussion: Chest x-ray with ILO technique is the basic instrument for the identification of diseases related to asbestos fiber exposure. The study should be completed with a CT scan of the chest, whose sensitivity is greater, allowing early detection of pleural abnormalities. It is essential to obtain a detailed occupational history, since it is the most reliable and practical method to measure asbestos fiber exposure.https://www.rbmt.org.br/details/1534/en-US/placas-pleurales-por-inhalacion-de-fibras-de-asbest

    Simulation of Subsurface Drainage in the Sugarcane Crop under Different Spacing and Drain Depths

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    Agricultural land drainage is an instrument for growing production and a tool for the conservation of land resources. The performance of land drainage systems is thus critical for achieving sustainable agricultural production Recently, many types of software have been developed in this field for modeling and simulating the performance of these systems. SISDRENA is a simulation model of the performance of underground drainage systems. The main objectives of this paper are to simulate different combination of depths and spaces between drains and to analyze their impact on potential sugarcane productivity in the western plains of Venezuela using a land drainage system model. Therefore, three climatic scenarios were defined by annual precipitation: dry years (25% below average), normal (mean) and humid (75% above average). The scenarios were implemented in three different soil types: sandy loam, loam and silt loam, with a hydraulic conductivity of 0.19, 0.26 and 0.04 m day−1, respectively. The simulation of the yield related to soil deficit (YRD) and water stress (YRW) indicated that the highest yields were reached for the larger spacing between drains and the high conductivity hydraulic of soils. In relation to the average relative productivity (YT), it was shown that in soils with a greater water retention capacity there is an inversely proportional relationship between the spacing between drains and the productivity. We concluded that in order to reach the maximum sugarcane yield, the effect of hydraulic conductivity is more important than the changes in the precipitation pattern

    Anomalous heavy-fermion and ordered states in the filled skutterudite PrFe4P12

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    Specific heat and magnetization measurements have been performed on high-quality single crystals of filled-skutterudite PrFe_4P_{12} in order to study the high-field heavy-fermion state (HFS) and low-field ordered state (ODS). From a broad hump observed in C/T vs T in HFS for magnetic fields applied along the direction, the Kondo temperature of ~ 9 K and the existence of ferromagnetic Pr-Pr interactions are deduced. The {141}-Pr nuclear Schottky contribution, which works as a highly-sensitive on-site probe for the Pr magnetic moment, sets an upper bound for the ordered moment as ~ 0.03 \mu_B/Pr-ion. This fact strongly indicates that the primary order parameter in the ODS is nonmagnetic and most probably of quadrupolar origin, combined with other experimental facts. Significantly suppressed heavy-fermion behavior in the ODS suggests a possibility that the quadrupolar degrees of freedom is essential for the heavy quasiparticle band formation in the HFS. Possible crystalline-electric-field level schemes estimated from the anisotropy in the magnetization are consistent with this conjecture.Comment: 7 pages and 7 figures. Accepted for publication in Phys. Rev.

    Odd Frequency Pairing in the Kondo Lattice

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    We discuss the possibility that heavy fermion superconductors involve odd-frequency pairing of the kind first considered by Berezinskii. Using a toy model for odd frequency triplet pairing in the Kondo lattice we are able to examine key properties of this new type of paired state. To make progress treating the strong nf=1n_f=1 constraint in the Kondo lattice model we use the technical trick of a Majorana representation of the local moments, which permits variational treatments of the model without a Gutzwiller approximation. The simplest mean field theory involves the development of bound states between the local moments and conduction electrons, characterized by a spinor order parameter. We show that this state is a stable realization of odd frequency triplet superconductivity with surfaces of gapless excitations whose spin and charge coherence factors vanish linearly in the quasiparticle energy. A T3T^3 NMR relaxation rate coexists with a linear specific heat. We discuss possible extensions of our toy model to describe heavy fermion superconductivity.Comment: 67 page

    Analyzing Patterns of Community Interest at a Legacy Mining Waste Site to Assess and Inform Environmental Health Literacy Efforts

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    Understanding a community’s concerns and infor-mational needs is crucial to conducting and improving envi-ronmental health research and literacy initiatives. We hypoth-esized that analysis of community inquiries over time at alegacy mining site would be an effective method for assessingenvironmental health literacy efforts and determining whethercommunity concerns were thoroughly addressed. Through aqualitative analysis, we determined community concerns atthe time of being listed as a Superfund site. We analyzedhow community concerns changed from this starting pointover the subsequent years, and whether: (1) communicationmaterials produced by the U.S. Environmental ProtectionAgency and other media were aligned with community con-cerns; and (2) these changes demonstrated a progression of thecommunity’s understanding resulting from community in-volvement and engaged research efforts. We observed thatwhen the Superfund site was first listed, community memberswere most concerned with USEPA management, remediation,site-specific issues, health effects, and environmental monitor-ing efforts related to air/dust and water. Over the next 5 years,community inquiries shifted significantly to include exposureassessment and reduction methods and issues unrelated to thesite, particularly the local public water supply and home watertreatment systems. Such documentation of community inqui-ries over time at contaminated sites is a novel method to assessenvironmental health literacy efforts and determine whethercommunity concerns were thoroughly addressed.12 month embargo; published online: 21 July 2015This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
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