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Very Short Period (very + short_period)
Selected AbstractsPredation by brown trout: a major mortality factor for sexually mature European minnowsJOURNAL OF FISH BIOLOGY, Issue 3 2003J. Museth Brown trout Salmo trutta in the subalpine lake, Řvre Heimdalsvatn, showed large temporal variation in the rate of predation on the introduced minnow Phoxinus phoxinus population. Minnows were found in the stomachs of brown trout between 16 and 38 cm LT. Significantly greater predation was recorded shortly after ice break at the end of June 1999, with frequencies of 9 and 20% within the LT classes 16,29·9 cm and ,30 cm, respectively. Predation on minnows was only occasionally detected during July, August and September. The high level of predation coincided with minnow spawning, and lengths of consumed minnows were equal to those of sexually mature individuals. Accepting a causal link between minnow spawning, which lasted c. 3 weeks, and the contemporary high rate of predation, the estimated annual consumption of minnows by the brown trout population would be 138 kg wet mass. Although most of the annual consumption of minnows by brown trout (90%) occurred within a very short period (3 weeks), it accounted for a significant proportion (60%) of the annual loss in biomass of the sexually mature part of the population. [source] Design and synthesis of a novel intercalating isoxazolyl bis-lexitropsin conjugateJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 2 2001Xiaochun Han 9-Anthracene nitrile oxide directly generated from 9-anthracenealdoxime and N -chlorosuccinamide (NCS), reacts with dimethyl acetylenedicarboxylate (DMAD) and affords the corresponding 3-(9,-anthra-cenyl)-isoxazole-4,5-dicarboxylic acid ester (3) with good yield in a very short period. Double activation reaction between (3) and hydrogenated lexitropsin (5) in a 1:2 molar ratio, produced a bis-lexitropsin product (6) (major product) and mono-lexitropsin product (7). [source] Vertical extrusion and middle crustal spreading of omphacite granulite: a model of syn-convergent exhumation (Bohemian Massif, Czech Republic)JOURNAL OF METAMORPHIC GEOLOGY, Issue 3 2004típská Abstract The exhumation of eclogite facies granulites (Omp,Plg,Grt,Qtz,Rt) in the Rychleby Mts, eastern Czech Republic, was a localised process initiated by buckling of crustal layers in a thickened orogenic root. Folding and post-buckle flattening was followed by the main stage of exhumation that is characterized by vertical ductile extrusion. This process is documented by structural data, and the vertical ascent of rocks from a depth of c. 70 to c. 35 km is documented by metamorphic petrology. SHRIMP 206Pb/238U and 207Pb/206Pb evaporation zircon ages of 342 ± 5 and 341.4 ± 0.7 Ma date peak metamorphic conditions. The next stage of exhumation was associated with sideways flat thrusting associated with lateral viscous spreading of granulites and surrounding rocks over indenting adjacent continental crust at a depth of c. 35,30 km. This stage was associated with syntectonic intrusion of a granodiorite sill at 345,339 Ma, emplaced at a crustal depth of c. 25 km. The time required for cooling of the sill as well as for heating of the country rocks brackets this event to a maximum of 250 000 years. Therefore, similar ages of crystallization for the granodiorite magma and the peak of eclogite facies metamorphism of the granulite suggest a very short period of exhumation, limited by the analytical errors of the dating methods. Our calculations suggest that the initial exhumation rate during vertical extrusion was 3,15 mm yr,1, followed by an exhumation rate of 24,40 mm yr,1 during further uplift along a magma-lubricated shear zone. The extrusion stage of exhumation was associated with a high cooling rate, which decreased during the stage of lateral spreading. [source] DSM-III and the revolution in the classification of mental illnessJOURNAL OF THE HISTORY OF THE BEHAVIORAL SCIENCES, Issue 3 2005Rick Mayes A revolution occurred within the psychiatric profession in the early 1980s that rapidly transformed the theory and practice of mental health in the United States. In a very short period of time, mental illnesses were transformed from broad, etiologically defined entities that were continuous with normality to symptom-based, categorical diseases. The third edition of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders (DSM-III) was responsible for this change. The paradigm shift in mental health diagnosis in the DSM-III was neither a product of growing scientific knowledge nor of increasing medicalization. Instead, its symptom-based diagnoses reflect a growing standardization of psychiatric diagnoses. This standardization was the product of many factors, including: (1) professional politics within the mental health community, (2) increased government involvement in mental health research and policymaking, (3) mounting pressure on psychiatrists from health insurers to demonstrate the effectiveness of their practices, and (4) the necessity of pharmaceutical companies to market their products to treat specific diseases. This article endeavors to explain the origins of DSM-III, the political struggles that generated it, and its long-term consequences for clinical diagnosis and treatment of mental disorders in the United States. © 2005 Wiley Periodicals, Inc. [source] Brachypodium: a new monocot model plant system emergesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 7 2007David F Garvin Abstract The small grass species Brachypodium distachyon (purple false brome) is potentially an ideal model plant system for grass crop research. To realise this potential, a range of genetic and genomic resources have been developed in a very short period of time, and more still are in the pipeline. David Garvin explains how these resources will establish B. distachyon as the newest model plant system and will fill a long-empty void in genomics resources for grass crop improvement. Copyright © 2007 Society of Chemical Industry [source] Histopathologic Maturation of Juvenile Xanthogranuloma in a Short PeriodPEDIATRIC DERMATOLOGY, Issue 2 2001Yumiko Kubota M.D. The initial biopsy specimen showed a dense collection of small histiocytes as evidenced by CD68 staining without either lipidization or giant cell formation, admixed with a small number of lymphocytes. On the other hand, sections from the excised specimen obtained 2 weeks after the initial biopsy from the same site showed a mixed proliferation of abundant foam cells together with Touton giant cells, some small histiocytes, and small numbers of lymphocytes and eosinophils. Mitotic figures were fewer in the excised nodule than in the initial biopsy specimen. Fascicles of spindle-shaped cells arranged in a vague storiform pattern were additionally found in the deep portion of the nodule. Our case findings suggest that xanthomatization of the JXG could have been accelerated by the inflammation associated with the biopsy, based on the histopathologic fact that the change from an early phase to a mature form occurred within the very short period of 2 weeks. [source] Sex differentials in frailty in medieval EnglandAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2010Sharon N. DeWitte Abstract In most modern populations, there are sex differentials in morbidity and mortality that favor women. This study addresses whether such female advantages existed to any appreciable degree in medieval Europe. The analyses presented here examine whether men and women with osteological stress markers faced the same risks of death in medieval London. The sample used for this study comes from the East Smithfield Black Death cemetery in London. The benefit of using this cemetery is that most, if not all, individuals interred in East Smithfield died from the same cause within a very short period of time. This allows for the analysis of the differences between men and women in the risks of mortality associated with osteological stress markers without the potential confounding effects of different causes of death. A sample of 299 adults (173 males, 126 females) from the East Smithfield cemetery was analyzed. The results indicate that the excess mortality associated with several osteological stress markers was higher for men than for women. This suggests that in this medieval population, previous physiological stress increased the risk of death for men during the Black Death to a greater extent than was true for women. Alternatively, the results might indicate that the Black Death discriminated less strongly between women with and without pre-existing health conditions than was true for men. These results are examined in light of previous analyses of East Smithfield and what is known about diet and sexually mediated access to resources in medieval England. Am J Phys Anthropol 143:285,297, 2010. © 2010 Wiley-Liss, Inc. [source] A Morphological Study of Skeletal Development in Turkey during the Pre-Hatching StageANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 1 2009S. H. Atalgin Summary Skeletal chondrofication, ossification and growth of turkey embryos were investigated and analysed to enable assessment of the developmental status and evaluation of the experimental effects on skeletal development, skeletal mutations and development of cultured embryos. Ten embryos were prepared every 24 h from 8 to 28 days of incubation. The fixed embryos were cleared and stained in toto with Alcian blue & Alizarin red for cartilage and ossified components, respectively. Observation of the skeleton was performed under a stereoscopic microscopy, with special attention to the timing of chondrofication and ossification of the bones. The first occurrence of the primary ossification centres was observed in the femur, tibiotarsus, and the dentary and supra-angular of the mandible on the 12th day, followed immediately by the other long bones. Skeletal features of the skull were determined to show the latest appearance of cartilage and ossification. Hence, all elements of the hyolingual apparatus remained cartilaginous until hatching took place except for the ceratobranchial. Even though the vertebral column chondrified earlier as compared with the ribs and sternum, they ossified later. While chondrofication was present in all the regions of the vertebral column at the same time, ossification progressed from the cervical through caudal regions. The growth rate of the femur was eminently higher than that of the humerus with increase in time, particularly after the 20th day of incubation. This seems to be obviously natural because the eggs used in the study are from the broiler turkey, which gains giant muscle mass at a very short period; precocity is probably at the expense of the bones of the leg rather than those of the wing. [source] Avian fruit consumption and seed dispersal in a temperate Australian woodlandAUSTRAL ECOLOGY, Issue 2 2002Margaret C. Stanley Abstract The effectiveness of avian fruit consumers as seed dispersers of fleshy-fruited plants was studied in a temperate woodland community. As a consequence of the short and overlapping fruiting phenologies of fleshy-fruited plant species in temperate regions of Australia, there are very few avian species that are true specialist frugivores. The relative importance of bird species as fruit consumers was investigated, and how their foraging activities, movements and gut treatment of seeds affected dispersal of viable seeds away from the parent plant was examined. Fruit consumption and consumer seed dispersal capacity were assessed in this study through faecal analyses and by testing the viability of seeds that had passed through the gut of avian consumers. Behavioural observations enabled us to determine the consumption rates of, and quantities of fruit consumed by, various bird species and the amount of time spent feeding. Silvereyes (Zosterops lateralis) were the dominant fruit consumers in the community, although 19 bird species were either observed consuming fruit or provided faecal samples that contained fruit. Silvereyes had a high local abundance at the site and more than 90% of silvereyes'faecal samples contained the seeds of fruiting plants (n = 409). Large numbers of fruit were consumed per visit by silvereyes, particularly for Rhagodia parabolica (fragrant saltbush). Silvereyes consumed an average of four R. parabolica fruit per 5 s and up to a maximum 40 fruit per visit. Viability was high for seeds recovered from silvereyes'faeces (R. parabolica, 94.4% viable; Hymenanthera dentata, 100% viable). However, the number of seeds per faecal sample was high for R. parabolica, which may result in density-dependent seed mortality. Gut passage rate for silvereyes fed R. parabolica fruit in captivity was 31.5 ± 1.9 min. Silvereyes remained at fruiting plants for very short periods (average 50-60 s) and in most cases moved away from the parent plant, primarily toward canopy trees. Given the short visit duration of silvereyes, individuals would have left the parent plant well before seeds passed through the gut. Rhagodia parabolica fruit was consumed by a large number of bird species in the community, including species often thought of as exclusively insectivorous or nectarivorous. These species are likely to disperse viable R. parabolica seeds into microhabitats different from those visited by silvereyes. [source] | ||||||||||||||||