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81.
We propose a class of dependent processes in which density shape is regressed on one or more predictors through conditional tail-free probabilities by using transformed Gaussian processes. A particular linear version of the process is developed in detail. The resulting process is flexible and easy to fit using standard algorithms for generalized linear models. The method is applied to growth curve analysis, evolving univariate random effects distributions in generalized linear mixed models, and median survival modelling with censored data and covariate-dependent errors. 相似文献
82.
Gracia-Marco L Valtueña J Ortega FB Pérez-López FR Vicente-Rodríguez G Breidenassel C Ferrari M Molnar D Widhalm K de Henauw S Kafatos A Diaz LE Gottrand F Maiani G Stehle P Castillo MJ Moreno LA González-Gross M;on behalf of the HELENA Study Group 《Journal of applied physiology (Bethesda, Md. : 1985)》2012,113(4):566-573
There is a lack of studies that analyze the association between micronutrient-related biomarker status and physical fitness in adolescents. In the present study, biochemical parameters for iron and vitamin status were studied, along with objective measures of physical fitness in healthy male and female European adolescents. One thousand eighty-nine adolescents (580 girls, 12.5-17.5 yr) from the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) cross-sectional study were included. Hierarchical linear models were performed to determine the associations between micronutrient biomarkers and physical fitness. Age, seasonality, latitude, body mass index, menarche (in girls), and physical activity were used as covariates. For cardiorespiratory fitness, concentrations of hemoglobin, retinol, and vitamin C in male adolescents and β-carotene and 25(OH)D in female adolescents were associated with maximal oxygen consumption. For muscular fitness, concentrations of hemoglobin, β-carotene, retinol, and α-tocopherol in male adolescents and β-carotene and 25(OH)D in female adolescents were associated with better performance of the standing long jump test. In summary, concentrations of hemoglobin and most antioxidant vitamins in male adolescents and β-carotene and 25(OH)D in female adolescents were positively associated with cardiorespiratory and muscular fitness, after controlling for relevant confounders. The associations between physical fitness and iron or vitamin status observed in this cross-sectional study in adolescents should be followed up by a study specifically designed to evaluate causal relationships. 相似文献
83.
Georgina Bond-Buckup Carlos G. Jara Marcos Pérez-Losada Ludwig Buckup Keith A. Crandall 《Hydrobiologia》2008,595(1):267-273
The freshwater anomuran crabs of the family Aeglidae are all restricted to southern South America occurring in Chile, Brazil,
Bolivia, Uruguay, Paraguay, and Argentina. The family consists of a single genus, Aegla, containing 63 currently described species. There are another 5–10 known yet undescribed species to complement this diversity.
The aeglids occur in freshwater lakes, streams, rivers, and in caves with freshwater. The origin of the family appears to
be from marine ancestors from the Pacific invading streams in Chile about 75 mya radiating both in Chile and again on the
eastern side of the Andes, particularly in Brazil. Of the 63 species, 23 or 36.5% are considered under threat and are in need
of conservation action.
Guest editors: E. V. Balian, C. Lévêque, H. Segers & K. Martens
Freshwater Animal Diversity Assessment 相似文献
84.
The Effects of the Organic Flame‐Retardant 1,2‐Dibromo‐4‐(1,2‐dibromoethyl) Cyclohexane (TBECH) on Androgen Signaling in Human Prostate Cancer Cell Lines 下载免费PDF全文
Lilian I. L. Wong Alexandra R. Reers Heidi A. Currier Tony D. Williams Michael E. Cox John E. Elliott Timothy V. Beischlag 《Journal of biochemical and molecular toxicology》2016,30(5):239-242
The effects of the organic flame retardant 1,2‐Dibromo‐4‐(1,2‐dibromoethyl) cyclohexane (TBECH) on androgen receptor target gene expression were examined in the human LNCaP prostate cancer cell line. While γ‐/δ‐TBECH alone led to a significant increase in prostate‐specific antigen (PSA) mRNA accumulation, both the α‐/‐TBECH and γ‐/δ‐TBECH mixtures repressed androgen‐inducible PSA mRNA and protein accumulation in human LNCaP cells. Thus, we hypothesize that isomeric mixtures of TBECH may act as partial agonists of the androgen receptor. 相似文献
85.
Willian Batista‐Silva David B. Medeiros Accio Rodrigues‐Salvador Danilo M. Daloso Rebeca P. Omena‐Garcia Franciele Santos Oliveira Lilian Ellen Pino Lzaro Eustquio Pereira Peres Adriano Nunes‐Nesi Alisdair R. Fernie Agustín Zsgn Wagner L. Araújo 《Plant, cell & environment》2019,42(2):448-465
Auxin modulates a range of plant developmental processes including embryogenesis, organogenesis, and shoot and root development. Recent studies have shown that plant hormones also strongly influence metabolic networks, which results in altered growth phenotypes. Modulating auxin signalling pathways may therefore provide an opportunity to alter crop performance. Here, we performed a detailed physiological and metabolic characterization of tomato (Solanum lycopersicum) mutants with either increased (entire) or reduced (diageotropica—dgt) auxin signalling to investigate the consequences of altered auxin signalling on photosynthesis, water use, and primary metabolism. We show that reduced auxin sensitivity in dgt led to anatomical and physiological modifications, including altered stomatal distribution along the leaf blade and reduced stomatal conductance, resulting in clear reductions in both photosynthesis and water loss in detached leaves. By contrast, plants with higher auxin sensitivity (entire) increased the photosynthetic capacity, as deduced by higher Vcmax and Jmax coupled with reduced stomatal limitation. Remarkably, our results demonstrate that auxin‐sensitive mutants (dgt) are characterized by impairments in the usage of starch that led to lower growth, most likely associated with decreased respiration. Collectively, our findings suggest that mutations in different components of the auxin signalling pathway specifically modulate photosynthetic and respiratory processes. 相似文献
86.
Jacquamet L Ohana J Joly J Borel F Pirocchi M Charrault P Bertoni A Israel-Gouy P Carpentier P Kozielski F Blot D Ferrer JL 《Structure (London, England : 1993)》2004,12(7):1219-1225
Crystallogenesis, usually based on the vapor diffusion method, is currently considered one of the most difficult steps in macromolecular X-ray crystallography. Due to the increasing number of crystallization assays performed by protein crystallographers, several automated analysis methods are under development. Most of these methods are based on microscope images and shape recognition. We propose an alternative method of identifying protein crystals: by directly exposing the crystallization drops to an X-ray beam. The resulting diffraction provides far more information than classical microscope images. Not only is the presence of diffracting crystals revealed, but also a first estimation of the space group, cell parameters, and mosaicity is obtained. In certain cases, it is also possible to collect enough data to verify the presence of a specific substrate or a heavy atom. All these steps are performed without the sometimes tedious necessity of removing crystals from their crystallization drop. 相似文献
87.
Ronivaldo Rodrigues da Silva Tatiane Beltramini Souto Tássio Brito de Oliveira Lilian Caroline Gonçalves de Oliveira Daniel Karcher Maria Aparecida Juliano Luiz Juliano Arthur H. C. de Oliveira André Rodrigues Jose C. Rosa Hamilton Cabral 《Journal of industrial microbiology & biotechnology》2016,43(8):1059-1069
In this study, we detail the specificity of an aspartic peptidase from Rhizomucor miehei and evaluate the effects of this peptidase on clotting milk using the peptide sequence of k-casein (Abz-LSFMAIQ-EDDnp) and milk powder. Molecular mass of the peptidase was estimated at 37 kDa, and optimum activity was achieved at pH 5.5 and 55 °C. The peptidase was stable at pH values ranging from 3 to 5 and temperatures of up 45 °C for 60 min. Dramatic reductions in proteolytic activity were observed with exposure to sodium dodecyl sulfate, and aluminum and copper (II) chloride. Peptidase was inhibited by pepstatin A, and mass spectrometry analysis identified four peptide fragments (TWSISYGDGSSASGILAK, ASNGGGGEYIFGGYDSTK, GSLTTVPIDNSR, and GWWGITVDRA), similar to rhizopuspepsin. The analysis of catalytic specificity showed that the coagulant activity of the peptidase was higher than the proteolytic activity and that there was a preference for aromatic, basic, and nonpolar amino acids, particularly methionine, with specific cleavage of the peptide bond between phenylalanine and methionine. Thus, this peptidase may function as an important alternative enzyme in milk clotting during the preparation of cheese. 相似文献
88.
Laplaze L Parizot B Baker A Ricaud L Martinière A Auguy F Franche C Nussaume L Bogusz D Haseloff J 《Journal of experimental botany》2005,56(419):2433-2442
Lateral root development occurs throughout the life of the plant and is responsible for the plasticity of the root system. In Arabidopsis thaliana, lateral root founder cells originate from pericycle cells adjacent to xylem poles. In order to study the mechanisms of lateral root development, a population of Arabidopsis GAL4-GFP enhancer trap lines were screened and two lines were isolated with GAL4 expression in root xylem-pole pericycle cells (J0121), i.e. in cells competent to become lateral root founder cells, and in young lateral root primordia (J0192). These two enhancer trap lines are very useful tools with which to study the molecular and cellular bases of lateral root development using targeted gene expression. These lines were used for genetic ablation experiments by targeting the expression of a toxin-encoding gene. Moreover, the molecular bases of the enhancer trap expression pattern were characterized. These results suggest that the lateral-root-specific GAL4 expression pattern in J0192 is due to a strong enhancer in the promoter of the LOB-domain protein gene LBD16. 相似文献
89.
90.