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61.
Stanislav I. Melnitsky Vladimir D. Ivanov Mikhail Yu Valuyskiy Lydia V. Zueva Marianna I. Zhukovskaya 《Arthropod Structure & Development》2018,47(1):45-55
Structure and distribution of sensilla were studied in sixteen species of the caddisfly family Philopotamidae. Their antennae bear numerous curved trichoid and pseudoplacoid sensilla and fewer coronal, styloconic and chaetoid sensilla on the flagellar segments. The most numerous pseudoplacoid sensilla have non-specific localization. The curved trichoid sensilla form clusters ventrally on each antennal segment. Sensilla belonging to coronal, styloconic and chaetoid types have specific positions. Long grooved trichoid sensilla are located nonspecifically in all the studied species. The average number of sensilla per segment decreases from the proximal to distal part of the flagellum. Scapus and pedicellum are devoid of most types of sensilla, however, they bear the Böhm bristles and long trichoid sensilla. A positive correlation between antenna dimensions and its cuticular structures is found. 相似文献
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Progressive brain metabolic changes under deep brain stimulation of subthalamic nucleus in parkinsonian rats 下载免费PDF全文
Guy Bielicki Jean‐Pierre Renou Lydia Kerkerian‐Le Goff Franck Durif 《Journal of neurochemistry》2015,132(6):703-712
Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an efficient neurosurgical treatment for advanced Parkinson's disease. Non‐invasive metabolic neuroimaging during the course of DBS in animal models may contribute to our understanding of its action mechanisms. Here, DBS was adapted to in vivo proton magnetic resonance spectroscopy at 11.7 T in the rat to follow metabolic changes in main basal ganglia structures, the striatum, and the substantia nigra pars reticulata (SNr). Measurements were repeated OFF and ON acute and subchronic (7 days) STN‐DBS in control and parkinsonian (6‐hydroxydopamine lesion) conditions. Acute DBS reversed the increases in glutamate, glutamine, and GABA levels induced by the dopamine lesion in the striatum but not in the SNr. Subchronic DBS normalized GABA in both the striatum and SNr, and glutamate in the striatum. Taurine levels were markedly decreased under subchronic DBS in the striatum and SNr in both lesioned and unlesioned rats. Microdialysis in the striatum further showed that extracellular taurine was increased. These data reveal that STN‐DBS has duration‐dependent metabolic effects in the basal ganglia, consistent with development of adaptive mechanisms. In addition to counteracting defects induced by the dopamine lesion, prolonged DBS has proper effects independent of the pathological condition.
66.
Eida M. Castro Lydia E. Santiago Julio C. Jiménez Daira Dávila-Vargas Milagros C. Rosal 《PloS one》2015,10(9)
Purpose
To identify perceived barriers and facilitators for HAART adherence among people living with HIV/AIDS in Southern Puerto Rico using a Social Ecological framework.Patients and Methods
Individual in-depths interviews were conducted with 12 HIV patients with a history of HAART non-adherence. Interviews were audio-taped and transcribed. Content analysis was performed for each transcribed interview by three independent coders using a codebook. Using Atlas TI, super-codes and families were generated to facilitate the categorization tree as well as grounded analyses and density estimatesResults
Most participants reported a monthly income of $500 or less (n = 7), a high school education level (n = 7), being unemployed (n = 9) and being recipients of government health insurance (n = 11). Three out of six women reported living alone with their children and most men informed living with their parents or other relatives (n = 4). For the grounded analyses, the top four sub-categories linked to high number of quotations were mental health barriers (G = 32) followed by treatment regimen (G = 28), health system (G = 24) and interpersonal relations (G = 16). The top four sub-categories linked to high number of codes are treatment regimen (D = 4), health status perception (D = 3), interpersonal relations (D = 3) and health system (D = 3).Conclusion
The results of this study suggest the interconnection of HIV treatment adherence barriers at various system levels. Future studies on HIV treatment barriers should explore these interactions and investigate the possible synergistic effect on non-adherent behavior 相似文献67.
Galo Garcia III Gregory C. Finnigan Lydia R. Heasley Sarah M. Sterling Adeeti Aggarwal Chad G. Pearson Eva Nogales Michael A. McMurray Jeremy Thorner 《The Journal of cell biology》2016,212(5):515-529
Septin complexes display remarkable plasticity in subunit composition, yet how a new subunit assembled into higher-order structures confers different functions is not fully understood. Here, this question is addressed in budding yeast, where during meiosis Spr3 and Spr28 replace the mitotic septin subunits Cdc12 and Cdc11 (and Shs1), respectively. In vitro, the sole stable complex that contains both meiosis-specific septins is a linear Spr28–Spr3–Cdc3–Cdc10–Cdc10–Cdc3–Spr3–Spr28 hetero-octamer. Only coexpressed Spr3 and Spr28 colocalize with Cdc3 and Cdc10 in mitotic cells, indicating that incorporation requires a Spr28-Spr3 protomer. Unlike their mitotic counterparts, Spr28-Spr3–capped rods are unable to form higher-order structures in solution but assemble to form long paired filaments on lipid monolayers containing phosphatidylinositol-4,5-bisphosphate, mimicking presence of this phosphoinositide in the prospore membrane. Spr28 and Spr3 fail to rescue the lethality of a cdc11Δ cdc12Δ mutant, and Cdc11 and Cdc12 fail to restore sporulation proficiency to spr3Δ/spr3Δ spr28Δ/spr28Δ diploids. Thus, specific meiotic and mitotic subunits endow septin complexes with functionally distinct properties. 相似文献
68.
Association mapping of complex traits typically employs tagSNP genotype data to identify a trait locus within a region of interest. However, considerable debate exists regarding the most powerful strategy for utilizing such tagSNP data for inference. A popular approach tests each tagSNP within the region individually, but such tests could lose power as a result of incomplete linkage disequilibrium between the genotyped tagSNP and the trait locus. Alternatively, one can jointly test all tagSNPs simultaneously within the region (by using genotypes or haplotypes), but such multivariate tests have large degrees of freedom that can also compromise power. Here, we consider a semiparametric model for quantitative-trait mapping that uses genetic information from multiple tagSNPs simultaneously in analysis but produces a test statistic with reduced degrees of freedom compared to existing multivariate approaches. We fit this model by using a dimension-reducing technique called least-squares kernel machines, which we show is identical to analysis using a specific linear mixed model (which we can fit by using standard software packages like SAS and R). Using simulated SNP data based on real data from the International HapMap Project, we demonstrate that our approach often has superior performance for association mapping of quantitative traits compared to the popular approach of single-tagSNP testing. Our approach is also flexible, because it allows easy modeling of covariates and, if interest exists, high-dimensional interactions among tagSNPs and environmental predictors. 相似文献
69.
Stoichiometry of soil enzyme activity at global scale 总被引:27,自引:0,他引:27
Sinsabaugh RL Lauber CL Weintraub MN Ahmed B Allison SD Crenshaw C Contosta AR Cusack D Frey S Gallo ME Gartner TB Hobbie SE Holland K Keeler BL Powers JS Stursova M Takacs-Vesbach C Waldrop MP Wallenstein MD Zak DR Zeglin LH 《Ecology letters》2008,11(11):1252-1264
Extracellular enzymes are the proximate agents of organic matter decomposition and measures of these activities can be used as indicators of microbial nutrient demand. We conducted a global-scale meta-analysis of the seven-most widely measured soil enzyme activities, using data from 40 ecosystems. The activities of beta-1,4-glucosidase, cellobiohydrolase, beta-1,4-N-acetylglucosaminidase and phosphatase g(-1) soil increased with organic matter concentration; leucine aminopeptidase, phenol oxidase and peroxidase activities showed no relationship. All activities were significantly related to soil pH. Specific activities, i.e. activity g(-1) soil organic matter, also varied in relation to soil pH for all enzymes. Relationships with mean annual temperature (MAT) and precipitation (MAP) were generally weak. For hydrolases, ratios of specific C, N and P acquisition activities converged on 1 : 1 : 1 but across ecosystems, the ratio of C : P acquisition was inversely related to MAP and MAT while the ratio of C : N acquisition increased with MAP. Oxidative activities were more variable than hydrolytic activities and increased with soil pH. Our analyses indicate that the enzymatic potential for hydrolyzing the labile components of soil organic matter is tied to substrate availability, soil pH and the stoichiometry of microbial nutrient demand. The enzymatic potential for oxidizing the recalcitrant fractions of soil organic material, which is a proximate control on soil organic matter accumulation, is most strongly related to soil pH. These trends provide insight into the biogeochemical processes that create global patterns in ecological stoichiometry and organic matter storage. 相似文献
70.
The extent of cultural variation between adjacent chimpanzee (Pan troglodytes verus) communities; A microecological approach 下载免费PDF全文
Chimpanzees show cultural differences among populations across Africa but also between neighboring communities. The extent of these differences among neighbors, however, remains largely unknown. Comparing three neighboring chimpanzee community in the Taï National Park, Côte d'Ivoire, we found 27 putative cultural traits, including tool use, foraging, social interaction, communication and hunting behavior, exceeding by far previously known diversity. As foraging behavior is predominantly influenced by the environment, we further compared in detail ecological circumstances underlying insectivore feeding behavior to analyze whether foraging differences on Dorylus ants and Thoracotermes termites seen between neighboring chimpanzee communities were caused by environmental factors. Differences in the prey characteristics of Dorylus ants (aggression level, running speed, and nest structure) that could influence the behavior of chimpanzees were excluded, suggesting that the observed group‐specific variation is not ecologically driven. Only one community preyed on Thoracotermes termites despite a similar abundance of termite mounds in all three territories, supporting the idea that this difference is also not shaped by the environment. Therefore, our study suggests that transmission of cultural knowledge plays a role in determining insectivory prey behavior. This behavioral plasticity, independent of ecological conditions, can lead to large numbers of cultural diversification between neighboring chimpanzee communities. These findings not only deepen our understanding of the cultural abilities of chimpanzees in the wild but also open up possible future comparisons of the origin of cultural diversification among humans and chimpanzees. Am J Phys Anthropol 156:67–75, 2015 © 2014 Wiley Periodicals, Inc. 相似文献