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981.
Miskulin M Petrović G Miskulin I Puntarić D Milas J Dahl D Rudan S 《Collegium antropologicum》2010,34(4):1315-1322
The aim of the study was to examine the prevalence of alcohol abuse among university students in Osijek, Croatia and its possible interconnections with gender, year of study, repetition of year of study, faculty subject area, sources of financing and type of residence during study. A validated questionnaire was self-administered to cross-faculty representative student sample of "J. J. Strossmayer" University of Osiek in June 2006. General demographic data, as well as data on academic features and student socio-economical status were obtained. The Alcohol Use Disorders Identification Test (AUDIT) was used for assessing the extent of alcohol consumption, with cut off value of 8 indicating possible alcohol problems. The majority of study participants 90.9% (755/831) had tried alcohol at least once in their life. Among this group, 43.8% (331/755) had an AUDIT total score of 8 or more: 69.2% (229/331) were males and 30.8% (102/331) were females. Among the study participants who screened positive, 70.4% (233/331) responded positively to simple advice focused on the reduction of hazardous drinking (AUDIT 8-15), 14.5% (48/331) needed brief counseling and continued monitoring (AUDIT 16-19), and 15.1% (50/331) clearly warranted further diagnostic evaluation for alcohol dependence (AUDIT 20 and above). Significantly different statistical data was found within the following factors: gender, repetition of year of study, faculty subject area and type of residence (chi2 = 76.232, p = 0.0000; Fisher exact test = 31.828, p = 0.0000; chi2 = 11.667, p = 0.0086 and chi2 = 6.639, p = 0.0362 respectively). Alcohol consumption resulting in risk behaviors is common among university students from eastern Croatia. These findings emphasize the need for comprehensive and effective preventative strategies directed towards student population. 相似文献
982.
Takako Sasaki Junichi Takagi Camilla Giudici Yoshihiko Yamada Eri Arikawa-Hirasawa Rainer Deutzmann Rupert Timpl Arnoud Sonnenberg Hans Peter Bächinger David Tonge 《Matrix biology》2010,29(6):484-493
Laminin-121, previously referred as to laminin-3, was expressed recombinantly in human embryonic kidney (HEK) 293 cells by triple transfection of full-length cDNAs encoding mouse laminin α1, β2 and γ1 chains. The recombinant laminin-121 was purified using Heparin-Sepharose followed by molecular sieve chromatography and shown to be correctly folded by electron microscopy and circular dichroism (CD). The CD spectra of recombinant laminin-121 were very similar to those of laminin-111 isolated from Engelbreth-Holm-Swarm tumor (EHS-laminin) but its Tm value was smaller than EHS-laminin and recombinant lamnin-111 suggesting that the replacement of the β chain reduced the stability of the coiled-coil structure of laminin-121. Its binding to integrins was compared with EHS-laminin, laminin-3A32 purified from murine epidermal cell line and recombinantly expressed laminins-111, -211 and -221. Laminin-121 showed the highest affinity to α6β1 and α7β1 integrins and furthermore, laminin-121 most effectively supported neurite outgrowth. Together, this suggests that the β2 laminins have higher affinity for integrins than the β1 laminins. 相似文献
983.
H. Charles J. Godfray Ian R. Crute Lawrence Haddad David Lawrence James F. Muir Nicholas Nisbett Jules Pretty Sherman Robinson Camilla Toulmin Rosalind Whiteley 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2010,365(1554):2769-2777
Although food prices in major world markets are at or near a historical low, there is increasing concern about food security—the ability of the world to provide healthy and environmentally sustainable diets for all its peoples. This article is an introduction to a collection of reviews whose authors were asked to explore the major drivers affecting the food system between now and 2050. A first set of papers explores the main factors affecting the demand for food (population growth, changes in consumption patterns, the effects on the food system of urbanization and the importance of understanding income distributions) with a second examining trends in future food supply (crops, livestock, fisheries and aquaculture, and ‘wild food’). A third set explores exogenous factors affecting the food system (climate change, competition for water, energy and land, and how agriculture depends on and provides ecosystem services), while the final set explores cross-cutting themes (food system economics, food wastage and links with health). Two of the clearest conclusions that emerge from the collected papers are that major advances in sustainable food production and availability can be achieved with the concerted application of current technologies (given sufficient political will), and the importance of investing in research sooner rather than later to enable the food system to cope with both known and unknown challenges in the coming decades. 相似文献
984.
Culicid larvae were collected in snow-melt pools during the first half of June from 1975-1977 and 1995-1996 in the Abisko Valley, Torne Lapmark, northern Sweden. Twelve species were collected from 102 pools and 81 localities with 7,914 specimens (elevations from 300 to 650 m a.s.l.). Fourteen species are now known from the area. Ten types of larval habitats were classified and ten species were statistically analyzed on pooled values over all years for abundance, coexistence, and diversity. The greatest abundance of individuals had pools with Carex spp. on the bottom. Most widespread and abundant were Oc. hexodontus (Dyar), Oc. communis (DeGeer), Oc. pullatus (Coquillett), and Oc. punctor (Kirby). The two circumpolar, arctic species, Oc. nigripes (Zetterstedt) and Oc. impiger (Walker), were mainly confined to elevations above 400 m a.s.l. In such marginal habitats as these pools, exposed to variable abitotic conditions, the phenology of species was rather constant. Species diversity varied somewhat between habitats. Oc. hexodontus, Oc. communis, and Oc. pullatus most often occupied pools as single species. Oc. communis and Oc. hexodontus had the highest values for coexistence and also occurred with Oc. punctor. The habitats that were richest in species were those without vegetation or with detritus on the bottom and surrounded by Empetrum nigrum and Betula nana. These habitats contained between eight and ten species. Species abundance and coexistence over the years showed no stable species patterns for the habitat types in the area. 相似文献
985.
Maria Löffler Julia Feldhues Sofia S. Venceslau Lydia Kammler Fabian Grein Inês A. C. Pereira Christiane Dahl 《Environmental microbiology》2020,22(2):783-795
Dissimilatory sulphite reductase DsrAB occurs in sulphate/sulphite-reducing prokaryotes, in sulphur disproportionators and also in sulphur oxidizers, where it functions in reverse. Predictions of physiological traits in metagenomic studies relying on the presence of dsrAB, other dsr genes or combinations thereof suffer from the lack of information on crucial Dsr proteins. The iron–sulphur flavoprotein DsrL is an example of this group. It has a documented essential function during sulphur oxidation and was recently also found in some metagenomes of probable sulphate and sulphite reducers. Here, we show that DsrL and reverse acting rDsrAB can form a complex and are copurified from the phototrophic sulphur oxidizer Allochromatium vinosum. Recombinant DsrL exhibits NAD(P)H:acceptor oxidoreductase activity with a strong preference for NADH over NADPH. In vitro, the rDsrABL complex effectively catalyses NADH-dependent sulphite reduction, which is strongly enhanced by the sulphur-binding protein DsrC. Our work reveals NAD+ as suitable in vivo electron acceptor for sulphur oxidation in organisms operating the rDsr pathway and points to reduced nicotinamide adenine dinucleotides as electron donors for sulphite reduction in sulphate/sulphite-reducing prokaryotes that contain DsrL. In addition, dsrL cannot be used as a marker distinguishing sulphate/sulphite reducers and sulphur oxidizers in metagenomic studies without further analysis. 相似文献
986.
Gisela C. Stotz James F. Cahill Jonathan A. Bennett Cameron N. Carlyle Edward W. Bork Diana Askarizadeh Sandor Bartha Carl Beierkuhnlein Bazartseren Boldgiv Leslie Brown Marcelo Cabido Giandiego Campetella Stefano Chelli Ofer Cohen Sandra Díaz Lucas Enrico David Ensing Batdelger Erdenetsetseg Alessandra Fidelis Heath W. Garris Hugh A. L. Henry Anke Jentsch Mohammad Hassan Jouri Kadri Koorem Peter Manning Randall Mitchell Mari Moora Gerhard E. Overbeck Jason Pither Kurt O. Reinhart Marcelo Sternberg Radnaakhand Tungalag Sainbileg Undrakhbold Margaretha van Rooyen Camilla Wellstein Martin Zobel Lauchlan H. Fraser 《Global Ecology and Biogeography》2020,29(3):482-490
987.
Camilla Fljgaard Jose W. Valdez Lars Dalby Jesper Erenskjold Moeslund Kevin K. Clausen Rasmus Ejrns Meelis Prtel Ane Kirstine Brunbjerg 《Ecology and evolution》2020,10(12):6078-6088
Species richness is the most commonly used metric to quantify biodiversity. However, examining dark diversity, the group of missing species which can potentially inhabit a site, can provide a more thorough understanding of the processes influencing observed biodiversity and help evaluate the restoration potential of local habitats. So far, dark diversity has mainly been studied for specific habitats or large‐scale landscapes, while less attention has been given to variation across broad environmental gradients or as a result of local conditions and biotic interactions. In this study, we investigate the importance of local environmental conditions in determining dark diversity and observed richness in plant communities across broad environmental gradients. Using the ecospace concept, we investigate how these biodiversity measures relate to abiotic gradients (defined as position), availability of biotic resources (defined as expansion), spatiotemporal extent of habitats (defined as continuity), and species interactions through competition. Position variables were important for both observed diversity and dark diversity, some with quadratic relationships, for example, plant richness showing a unimodal response to soil fertility corresponding to the intermediate productivity hypothesis. Interspecific competition represented by community mean Grime C had a negative effect on plant species richness. Besides position‐related variables, organic carbon was the most important variable for dark diversity, indicating that in late‐succession habitats such as forests and shrubs, dark diversity is generally low. The importance of highly competitive species indicates that intermediate disturbance, such as grazing, may facilitate higher species richness and lower dark diversity. 相似文献
988.
Ambrin Fatima Jan Hoeber Jens Schuster Eriko Koshimizu Carolina Maya-Gonzalez Boris Keren Cyril Mignot Talia Akram Zafar Ali Satoko Miyatake Junpei Tanigawa Takayoshi Koike Mitsuhiro Kato Yoshiko Murakami Uzma Abdullah Muhammad Akhtar Ali Rein Fadoul Loora Laan Niklas Dahl 《American journal of human genetics》2021,108(4):739-748
989.
Hydrobiologia - Attempts to restore Lake Lugano, Switzerland and Italy, from eutrophication have produced weak responses in the target variables (primary productivity and hypolimnetic oxygen... 相似文献
990.
Christopher Fortenbach Gabriel Peinado Allina Camilla M. Shores Sarah J. Karlen Eric B. Miller Hannah Bishop James S. Trimmer Marie E. Burns Edward N. Pugh Jr. 《The Journal of general physiology》2021,153(2)
Vertebrate retinal photoreceptors signal light by suppressing a circulating “dark current” that maintains their relative depolarization in the dark. This dark current is composed of an inward current through CNG channels and NCKX transporters in the outer segment that is balanced by outward current exiting principally from the inner segment. It has been hypothesized that Kv2.1 channels carry a predominant fraction of the outward current in rods. We examined this hypothesis by comparing whole cell, suction electrode, and electroretinographic recordings from Kv2.1 knockout (Kv2.1−/−) and wild-type (WT) mouse rods. Single cell recordings revealed flash responses with unusual kinetics, and reduced dark currents that were quantitatively consistent with the measured depolarization of the membrane resting potential in the dark. A two-compartment (outer and inner segment) physiological model based on known ionic mechanisms revealed that the abnormal Kv2.1−/− rod photoresponses arise principally from the voltage dependencies of the known conductances and the NCKX exchanger, and a highly elevated fraction of inward current carried by Ca2+ through CNG channels due to the aberrant depolarization. Kv2.1−/− rods had shorter outer segments than WT and dysmorphic mitochondria in their inner segments. Optical coherence tomography of knockout animals demonstrated a slow photoreceptor degeneration over a period of 6 mo. Overall, these findings reveal that Kv2.1 channels carry 70–80% of the non-NKX outward dark current of the mouse rod, and that the depolarization caused by the loss of Kv2.1 results in elevated Ca2+ influx through CNG channels and elevated free intracellular Ca2+, leading to progressive degeneration. 相似文献