1,406 research outputs found

    The SCOFF-c: Psychometric properties of the Catalan version in a Spanish adolescent sample

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    Objective The objective of this study is to validate the Catalan version of the SCOFF questionnaire with a community sample of adolescents. Method This study used a community sample of 954 participants (475 girls and 479 boys; aged between 10.9 and 17.3 years and from the city of Barcelona) and a risk group of 78 participants (35 men and 43 women; derived from the community sample) that have exceeded ≥95 percentile in at least two of the three scales of the Eating Disorders Inventory-2 (EDI-2): Drive for Thinness, Bulimia, and Body Dissatisfaction. Results There were significant differences in total SCOFF scores across gender and school grades. The SCOFF best cutoff point was 2 (sensitivity=73.08%; specificity=77.74%). Concurrent validity with the EDI-2 varied between low and moderate. The reliability of the SCOFF questionnaire was moderate. Exploratory factor analysis of the SCOFF questionnaire showed a two-factor structure for the total sample and for girls, and one factor for boys. Conclusion The best cutoff point for this community sample is 2. The data suggest that the SCOFF questionnaire could be a useful screening questionnaire to enable the detection of groups possibly at risk for eating disorders among adolescent Spanish community samples

    Review on possible gravitational anomalies

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    This is an updated introductory review of 2 possible gravitational anomalies that has attracted part of the Scientific community: the Allais effect that occur during solar eclipses, and the Pioneer 10 spacecraft anomaly, experimented also by Pioneer 11 and Ulysses spacecrafts. It seems that, to date, no satisfactory conventional explanation exist to these phenomena, and this suggests that possible new physics will be needed to account for them. The main purpose of this review is to announce 3 other new measurements that will be carried on during the 2005 solar eclipses in Panama and Colombia (Apr. 8) and in Portugal (Oct.15).Comment: Published in 'Journal of Physics: Conferences Series of the American Institute of Physics'. Contribution for the VI Mexican School on Gravitation and Mathematical Physics "Approaches to Quantum Gravity" (Playa del Carmen, Quintana Roo, Mexico, Nov. 21-27, 2004). Updates to this information will be posted in http://www.lsc-group.phys.uwm.edu/~xavier.amador/anomalies.htm

    Structural studies of cesium, lithium/cesium and sodium/cesium bis(trimethylsilyl)amide (HMDS) complexes

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    Reacting cesium fluoride with an equimolar n-hexane solution of lithium bis(trimethylsilyl)amide (LiHMDS), allows the isolation of CsHMDS (1) in 80% yield (after sublimation). This preparative route to 1 negates the need for pyrophoric Cs metal or organocesium reagents in its synthesis. If a 2:1 LiHMDS:CsF ratio is employed the heterobimetallic polymer [LiCs(HMDS)2]∞ 2 was isolated (57% yield). By combining equimolar quantities of NaHMDS and CsHMDS in hexane/toluene [NaCs(HMDS)2(toluene)]∞ 3 was isolated (62% yield). Attempts to prepare the corresponding potassium-cesium amide failed, and instead yielded the known monometallic polymer [Cs(HMDS)(toluene)]∞ 4. With the aim of expanding the structural diversity of Cs(HMDS) species, 1 was reacted with several different Lewis basic donor molecules of varying denticity; namely, (R,R)-N,N,N′,N′-tetramethylcyclohexane-1,2-diamine [(R,R)-TMCDA] and N,N,Nʹ,Nʹ-tetramethylethylenediamine (TMEDA), N,N,Nʹ,Nʹʹ,Nʹʹ-pentamethyldiethylenetriamine (PMDETA), tris[2-(dimethylamino)ethyl]amine (Me6-TREN) and tris[2-(2-methoxyethoxy)ethyl]amine (TMEEA). These reactions yielded dimeric [Cs(HMDS)·donor]2 5-7 [where donor is (R,R)-TMCDA, TMEDA and PMDETA respectively], the tetranuclear ‘open’-dimer [{Me6-TREN·Cs(HMDS)}2{Cs(HMDS)}2] 8 and the monomeric Cs(HMDS)·TMEEA 9. Complexes 2,3 and 5-9 were characterized by X-ray crystallography and in solution by multinuclear NMR spectroscopy

    Genome-by-Trauma Exposure Interactions in Adults With Depression in the UK Biobank

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    IMPORTANCE: Self-reported trauma exposure has consistently been found to be a risk factor for major depressive disorder (MDD), and several studies have reported interactions with genetic liability. To date, most studies have examined gene-environment interactions with trauma exposure using genome-wide variants (single-nucleotide variations [SNVs]) or polygenic scores, both typically capturing less than 3% of phenotypic risk variance. OBJECTIVE: To reexamine genome-by-trauma interaction associations using genetic measures using all available genotyped data and thus, maximizing accounted variance. DESIGN, SETTING, AND PARTICIPANTS: The UK Biobank study was conducted from April 2007 to May 1, 2016 (follow-up mental health questionnaire). The current study used available cross-sectional genomic and trauma exposure data from UK Biobank. Participants who completed the mental health questionnaire and had available genetic, trauma experience, depressive symptoms, and/or neuroticism information were included. Data were analyzed from April 1 to August 30, 2021. EXPOSURES: Trauma and genome-by-trauma exposure interactions. MAIN OUTCOMES AND MEASURES: Measures of self-reported depression, neuroticism, and trauma exposure with whole-genome SNV data are available from the UK Biobank study. Here, a mixed-model statistical approach using genetic, trauma exposure, and genome-by-trauma exposure interaction similarity matrices was used to explore sources of variation in depression and neuroticism. RESULTS: Analyses were conducted on 148 129 participants (mean [SD] age, 56 [7] years) of which 76 995 were female (52.0%). The study approach estimated the heritability (SE) of MDD to be approximately 0.160 (0.016). Subtypes of self-reported trauma exposure (catastrophic, adult, childhood, and full trauma) accounted for a significant proportion of the variance of MDD, with heritability (SE) ranging from 0.056 (0.013) to 0.176 (0.025). The proportion of MDD risk variance accounted for by significant genome-by-trauma interaction revealed estimates (SD) ranging from 0.074 (0.006) to 0.201 (0.009). Results from sex-specific analyses found genome-by-trauma interaction variance estimates approximately 5-fold greater for MDD in male participants (0.441 [0.018]) than in female participants (0.086 [0.009]). CONCLUSIONS AND RELEVANCE: This cross-sectional study used an approach combining all genome-wide SNV data when exploring genome-by-trauma interactions in individuals with MDD; findings suggest that such interactions were associated with depression manifestation. Genome-by-trauma interaction accounts for greater trait variance in male individuals, which points to potential differences in depression etiology between the sexes. The methodology used in this study can be extrapolated to other environmental factors to identify modifiable risk environments and at-risk groups to target with interventions

    Ameliorative effects of salt resistance on physiological parameters in the halophyte Salicornia bigelovii torr. with plant growth-promoting rhizobacteria

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    Salicornia bigelovii is a promising resource to cultivate under extreme climatic conditions of arid-desert regions. However, the production of Salicornia depends on the appropriate supplementation of nitrogen rich synthetic fertilizers. Application of specific halotolerant nitrogen-fixing bacteria associated with S. bigelovii could be an important practice for crop production in salt-affected regions. Seedlings of S. bigelovii were inoculated and developed with plant growth promoting rhizobacteria (Klebsiella pnseumoniae) at different salinities (0 and 0.25 M NaCl) grown under in vitro conditions. The inoculation increased growth and physiological activity at a high salinity. The major benefits of inoculation were observed on total seedlings biomass (320 and 175 g at 0 and 0.25 M NaCl, respectively) and adjacent branches of stem biomass (150 and 85 g at 0 and 0.25 M NaCl, respectively). The inoculation with Klebsiella pneumoniae also significantly improved seedlings salinity tolerance compared to the noninoculated controls. In non-salinity conditions, the inoculated seedlings enhanced the CO2 fixation and O2 evolution. The non-inoculated controls were more sensitive to salinity than inoculated seedlings exposed to salinity, as indicated by several measured parameters. Moreover, inoculated seedlings had significantly increase on proline, phenolics content, but not significant in starch compared to noninoculated controls. In conclusion, K. pneumoniae inoculation mitigates the salinity effects and promotes the Salicornia growth.Keywords: Salicornia bigelovii, Klebsiella pneumoniae, halophyte, ecotype, stress salinity. African Journal of Biotechnology Vol. 12(34), pp. 5278-528

    A biophysical model of prokaryotic diversity in geothermal hot springs

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    Recent field investigations of photosynthetic bacteria living in geothermal hot spring environments have revealed surprisingly complex ecosystems, with an unexpected level of genetic diversity. One case of particular interest involves the distribution along hot spring thermal gradients of genetically distinct bacterial strains that differ in their preferred temperatures for reproduction and photosynthesis. In such systems, a single variable, temperature, defines the relevant environmental variation. In spite of this, each region along the thermal gradient exhibits multiple strains of photosynthetic bacteria adapted to several distinct thermal optima, rather than the expected single thermal strain adapted to the local environmental temperature. Here we analyze microbiology data from several ecological studies to show that the thermal distribution field data exhibit several universal features independent of location and specific bacterial strain. These include the distribution of optimal temperatures of different thermal strains and the functional dependence of the net population density on temperature. Further, we present a simple population dynamics model of these systems that is highly constrained by biophysical data and by physical features of the environment. This model can explain in detail the observed diversity of different strains of the photosynthetic bacteria. It also reproduces the observed thermal population distributions, as well as certain features of population dynamics observed in laboratory studies of the same organisms

    Arabidopsis Heat Stress-Induced Proteins Are Enriched in Electrostatically Charged Amino Acids and Intrinsically Disordered Regions

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    [EN] Comparison of the proteins of thermophilic, mesophilic, and psychrophilic prokaryotes has revealed several features characteristic to proteins adapted to high temperatures, which increase their thermostability. These characteristics include a profusion of disulfide bonds, salt bridges, hydrogen bonds, and hydrophobic interactions, and a depletion in intrinsically disordered regions. It is unclear, however, whether such differences can also be observed in eukaryotic proteins or when comparing proteins that are adapted to temperatures that are more subtly different. When an organism is exposed to high temperatures, a subset of its proteins is overexpressed (heat-induced proteins), whereas others are either repressed (heat-repressed proteins) or remain unaffected. Here, we determine the expression levels of all genes in the eukaryotic model system Arabidopsis thaliana at 22 and 37 degrees C, and compare both the amino acid compositions and levels of intrinsic disorder of heat-induced and heat-repressed proteins. We show that, compared to heat-repressed proteins, heat-induced proteins are enriched in electrostatically charged amino acids and depleted in polar amino acids, mirroring thermophile proteins. However, in contrast with thermophile proteins, heat-induced proteins are enriched in intrinsically disordered regions, and depleted in hydrophobic amino acids. Our results indicate that temperature adaptation at the level of amino acid composition and intrinsic disorder can be observed not only in proteins of thermophilic organisms, but also in eukaryotic heat-induced proteins; the underlying adaptation pathways, however, are similar but not the same.D.A.-P. and F.F. were supported by funds from the University of Nevada, Reno, and by pilot grants from Nevada INBRE (P20GM103440) and the Smooth Muscle Plasticity COBRE from the University of Nevada, Reno (5P30GM110767-04), both funded by the National Institute of General Medical Sciences (National Institutes of Health). M.X.R.-G. and M.A.F. were supported by grants from Science Foundation Ireland (12/IP/1637) and the Spanish Ministerio de Economia y Competitividad, Spain (MINECO-FEDER; BFU201236346 and BFU2015-66073-P) to MAF. MXRG was supported by a JAE DOC fellowship from the MINECO, Spain. F.V.-S. and M.A.P.-A. were supported by grant BIO2014-55946-P from MINECO-FEDER.Alvarez-Ponce, D.; Ruiz-González, M.; Vera Sirera, FJ.; Feyertag, F.; Perez Amador, MA.; Fares Riaño, MA. (2018). Arabidopsis Heat Stress-Induced Proteins Are Enriched in Electrostatically Charged Amino Acids and Intrinsically Disordered Regions. International Journal of Molecular Sciences. 19(8). https://doi.org/10.3390/ijms19082276S198Karshikoff, A., & Ladenstein, R. (2001). Ion pairs and the thermotolerance of proteins from hyperthermophiles: a ‘traffic rule’ for hot roads. Trends in Biochemical Sciences, 26(9), 550-557. doi:10.1016/s0968-0004(01)01918-1Strop, P., & Mayo, S. L. (2000). Contribution of Surface Salt Bridges to Protein Stability†,‡. Biochemistry, 39(6), 1251-1255. doi:10.1021/bi992257jPERUTZ, M. F., & RAIDT, H. (1975). Stereochemical basis of heat stability in bacterial ferredoxins and in haemoglobin A2. Nature, 255(5505), 256-259. doi:10.1038/255256a0Argos, P., Rossmann, M. G., Grau, U. 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A., Nourse, A., Wang, Y., Sivakolundu, S. G., Heller, W. T., & Kriwacki, R. W. (2008). Role of Intrinsic Flexibility in Signal Transduction Mediated by the Cell Cycle Regulator, p27Kip1. Journal of Molecular Biology, 376(3), 827-838. doi:10.1016/j.jmb.2007.12.016Van Noort, V., Bradatsch, B., Arumugam, M., Amlacher, S., Bange, G., Creevey, C., … Bork, P. (2013). Consistent mutational paths predict eukaryotic thermostability. BMC Evolutionary Biology, 13(1), 7. doi:10.1186/1471-2148-13-7Wang, G.-Z., & Lercher, M. J. (2010). Amino acid composition in endothermic vertebrates is biased in the same direction as in thermophilic prokaryotes. BMC Evolutionary Biology, 10(1), 263. doi:10.1186/1471-2148-10-263Windisch, H. S., Lucassen, M., & Frickenhaus, S. (2012). Evolutionary force in confamiliar marine vertebrates of different temperature realms: adaptive trends in zoarcid fish transcriptomes. BMC Genomics, 13(1), 549. doi:10.1186/1471-2164-13-549Albanèse, V., Yam, A. Y.-W., Baughman, J., Parnot, C., & Frydman, J. (2006). Systems Analyses Reveal Two Chaperone Networks with Distinct Functions in Eukaryotic Cells. Cell, 124(1), 75-88. doi:10.1016/j.cell.2005.11.039Berry, J., & Bjorkman, O. (1980). Photosynthetic Response and Adaptation to Temperature in Higher Plants. Annual Review of Plant Physiology, 31(1), 491-543. doi:10.1146/annurev.pp.31.060180.002423Sueoka, N. (1961). CORRELATION BETWEEN BASE COMPOSITION OF DEOXYRIBONUCLEIC ACID AND AMINO ACID COMPOSITION OF PROTEIN. Proceedings of the National Academy of Sciences, 47(8), 1141-1149. doi:10.1073/pnas.47.8.1141Cherry, J. L. (2009). Highly Expressed and Slowly Evolving Proteins Share Compositional Properties with Thermophilic Proteins. Molecular Biology and Evolution, 27(3), 735-741. doi:10.1093/molbev/msp270The amino acid composition is different between the cytoplasmic and extracellular sides in membrane proteins. (1992). 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    Sequestered Dark Matter

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    We show that hidden-sector dark matter is a generic feature of the type IIB string theory landscape and that its lifetime may allow for a discovery through the observation of very energetic gamma-rays produced in the decay. Throats or, equivalently, conformally sequestered hidden sectors are common in flux compactifications and the energy deposited in these sectors can be calculated if the reheating temperature of the standard model sector is known. Assuming that throats with various warp factors are available in the compact manifold, we determine which throats maximize the late-time abundance of sequestered dark matter. For such throats, this abundance agrees with cosmological data if the standard model reheating temperature was 10^10 - 10^11 GeV. In two distinct scenarios, the mass of dark matter particles, i.e. the IR scale of the throat, is either around 10^5 GeV or around 10^10 GeV. The lifetime and the decay channels of our dark matter candidates depend crucially on the fact that the Klebanov-Strassler throat is supersymmetric. Furthermore, the details of supersymmetry breaking both in the throat and in the visible sector play an essential role. We identify a number of scenarios where this type of dark matter can be discovered via gamma-ray observations.Comment: 36 pages, 3 figures; v2: references added, v3: introduction extended and typos correcte

    Defectos visuales no corregidos y su relación con molestias musculo esqueléticas en cuello y espalda alta

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    Objective: To determine the prevalence of uncorrected ocular anomalies and its association with cervicalgias in a group of workers in the industrial sector. Methodology: Descriptive, correlational, cross-sectional study of 83 workers in the production area of ​​a lamp factory in Cali, 2011. Surveys of demographic, labor and previous visual defects were carried out. Undetected visual defects were evaluated with Snellen E optotype and direct internal and external examination to detect structural abnormalities. The presence of musculoskeletal pain in the neck and upper back was evaluated with the Nordic questionnaire. Results: The predominant visual defect was presbyopia (43.4%). The most prevalent musculoskeletal symptom was neck pain (44.6%). A significant association was found between having some visual defect and neck pain (P = 0.041). Conclusions: A relationship was found between visual defects and musculoskeletal discomfort in the neck. Periodic visual examinations are recommended to avoid the appearance of musculoskeletal disease.Objetivo: Determinar la prevalencia de anomalías oculares no corregidas y su asociación con cervicalgias en grupo de trabajadores del sector industrial. Metodología: Estudio descriptivo, correlacional, de corte transversal en 83 trabajadores del área de producción de una fábrica de lámparas en Cali, año 2011. Se realizaron encuestas de datos demográficos, laborales y defectos visuales previos. Los defectos visuales no detectados se evaluaron con, optotipo Snellen E y examen directo interno y externo para detección de anomalías estructurales. La presencia de dolor osteomuscular en cuello y espalda alta se evaluó con el cuestionario nórdico. Resultados: El defecto visual predominante fue presbicia (43,4%). El síntoma osteomuscularde mayor prevalencia fue dolor de cuello (44,6%). Se encontró una asociación significativa entre tener algún defecto visual y dolor en cuello (P=0,041). Conclusiones: Se encontró una relación entre los defectos visuales y molestias osteomusculares en cuello. Se recomienda realizar exámenes visuales periódicos para evitar la aparición de enfermedad osteomusculares

    Impurities in s=1s=1 Heisenberg Antiferromagnets

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    The s=1s=1 Heisenberg Antiferromagnet is studied in the presence of two kinds of local impurities. First, a perturbed antiferromagnetic bond with J′≠JJ'\ne J at the center of an even-length open chain is considered. Using the density matrix renormalization group method we find that, for sufficiently strong or weak J′J', a bound state is localized at the impurity site, giving rise to an energy level in the Haldane gap. The energy of the bound state is in agreement with perturbative results, based on s=1/2s=1/2 chain-end excitations, both in the weak and strong coupling limit. In a region around the uniform limit, J′=JJ'=J, no states are found with energy below the Haldane gap. Secondly, a s=1/2s=1/2 impurity at the center of an otherwise even-length open chain is considered. The coupling to the s=1/2s=1/2 impurity is varied. Bound states in the Haldane gap are found {\it only} for sufficiently weak (antiferromagnetic) coupling. For a s=1/2s=1/2 impurity coupled with a strong (antiferromagnetic) bond, {\it no} states are found in the Haldane. Our results are in good qualitative agreement with recent experiments on doped NENP and Y2_2BaNiO5_5.Comment: 29 pages, RevTeX 3.0, 12 uuencoded postscript figures include
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