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Possible Causes (possible + cause)
Kinds of Possible Causes Selected AbstractsMycophenolate Mofetil: A Possible Cause of Hemophagocytic Syndrome Following Renal Transplantation?AMERICAN JOURNAL OF TRANSPLANTATION, Issue 10 2010L. Raffray No abstract is available for this article. [source] Decrease in the Prevalence of Adolescent Alcohol Use and its Possible Causes in Japan: Periodical Nationwide Cross-Sectional SurveysALCOHOLISM, Issue 2 2009Yoneatsu Osaki Background:, Trends in alcohol drinking prevalence were assessed among Japanese adolescents, and possible reasons for a decrease in drinking prevalence observed in 2004. Methods:, Cross-sectional nationwide surveys were conducted periodically. High schools were randomly sampled from throughout Japan in 1996, 2000, and 2004. All enrolled students in sampled schools were subjects of the surveys. Self-reporting anonymous questionnaires were collected from 115,814 students in 1996, 106,297 in 2000, and 102,451 in 2004. Questions about drinking prevalence of students and family members, proportion of students who have no friends, and sources of alcohol were included. Students who drunk at least one day of the 30 days preceding the survey were defined as the current drinkers. Results:, The drinking prevalence in 2004 was decreased in comparison to that in 1996 and 2000 in both sexes and in all school grades. The current drinking rate (monthly drinker) among junior high school boys was 29.4% in 1996, 29.0% in 2000, and 20.5% in 2004, while that among senior high school boys was 49.7%, 48.7%, and 36.2%, respectively. The respective prevalence among junior and senior girls was 24.0%, 25.5%, and 20.0% and 40.8%, 42.1%, and 34.1%. The prevalent sources of alcohol beverages were searching in home, stores (convenience store, supermarket, or gas-stand), liquor shops, and bars. An analysis of the reasons for this decrease identified a decrease in drinking prevalence in students' families, especially by fathers and older brothers, and an increase in the proportion of students who had no friends. Conclusions:, A decrease in drinking prevalence of male family members and a limitation of sources of alcoholic beverages may contribute to the decrease in adolescent drinking prevalence. [source] Food Price Surges: Possible Causes, Past Experience, and Longer Term RelevancePOPULATION AND DEVELOPMENT REVIEW, Issue 4 2008Nikos Alexandratos The food price surges of recent years have created much misery and raised once again the Malthusian specter. Increases in the demand for food in the emerging economies, particularly China and India, have frequently been identified as the dominant factor behind a perceived shock on the demand side. Use of crops for biofuels was listed as an additional, though less important, factor. Yet global cereals utilization without biofuels has been growing at slowly decelerating rates, as in the past. It is the addition of biofuels that has resulted in its growing faster than in the past. In parallel, global production had been falling behind utilization for several years, leading to declining stocks. Weather shocks, depreciation of the dollar, and turbulence in the financial markets were added to these fundamentals of the supply,demand balance to generate the price surges. If energy prices remain high and/or rising and pro-biofuel policies remain in place, the diversion of crops to biofuels is likely to continue. This could prevent the current commodity cycle from unfolding in the "normal" way over the short to medium term with prices trending back toward their pre-surge levels. Conclusions are drawn about how these developments should influence the way we assess long-term food and agriculture prospects. [source] Nosocomial Clostridium difficile infection: Possible cause of anastomotic leakage after anterior resection of the rectumJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 5 2007Anil Keshava [source] Paradoxical Hypertrichosis After Laser Therapy: A ReviewDERMATOLOGIC SURGERY, Issue 3 2010SHRADDHA DESAI MD BACKGROUND Laser hair removal is a safe and effective procedure for the treatment of unwanted body hair but is not exempt from side effects. A rare but significant adverse effect with this treatment modality is paradoxical hypertrichosis. OBJECTIVE To evaluate the potential etiologies, risk factors, related laser types, and treatment options for the development of excess hair after laser therapy. MATERIALS AND METHODS An analysis of previously published case studies and review articles along with our own experience was used to gather information regarding this phenomenon. RESULTS Paradoxical hypertrichosis has a low incidence, ranging from 0.6% to 10%, and most commonly occurs on the face and neck. All laser and light sources have the potential to cause hair induction, especially in individuals with darker skin types (III,VI); with dark, thick hair; and with underlying hormonal conditions. Possible causes include the effect of inflammatory mediators and subtherapeutic thermal injury causing induction of the hair cycle. Treatment for paradoxical hypertrichosis is laser therapy of the affected area. CONCLUSIONS Paradoxical hypertrichosis is a rare side effect of laser hair removal; the pathogenesis of this event remains widely unknown. We recommend further large-scale studies to investigate this effect. The authors have indicated no significant interest with commercial supporters. [source] Burnout intervention among Dutch dentists: long-term effectsEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 6 2001Hans Te Brake The aim of the present study was to determine the long-term effects of a burnout-intervention program among Dutch dentists using a longitudinal design. Using the Maslach Burnout Inventory (Dutch version: MBI-NL), at the initial measurement in 1997 a ,burnout risk group' (n=171) was identified. This group received feedback on their scores and was invited to participate in an intervention program. Of the total group, 19 dentists participated in an intervention program. After the end of the intervention program, 92 dentists (the 19 participants and a control group) responded to a post-intervention survey in 1998. These dentists were approached once more 1 yr later, and this time 78 dentists (84.8%) returned a questionnaire. While demonstrating an improvement on all subscales of the MBI-NL at the first post-test, results show that the program participants showed a relapse at the second post-test. Controls who took action on their own initiative, on the other hand, reported a beneficial effect in the long run. Finally, controls that did not take any preventive action showed little or no progress. Possible causes for these findings are discussed, including the influence of coping style, perceived control, confounding factors, demand characteristics, and the necessity of post-intervention follow-up. [source] Net regional ecosystem CO2 exchange from airborne and ground-based eddy covariance, land-use maps and weather observationsGLOBAL CHANGE BIOLOGY, Issue 3 2007F. MIGLIETTA Abstract Measurements of regional net ecosystem exchange (NEE) were made over a period of 21 days in summer 2002 in the South-Central part of the Netherlands and extrapolated to an area of 13 000 km2 using a combination of flux measurements made by a Sky Arrow ERA research aircraft, half-hourly eddy covariance data from four towers, half-hourly weather data recorded by three weather stations and detailed information on regional land use. The combination of this type of information allowed to estimate the net contribution of the terrestrial ecosystems to the overall regional carbon flux and to map dynamically the temporal and spatial variability of the fluxes. A regional carbon budget was calculated for the study period and the contributions of the different land uses to the overall regional flux, were assessed. Ecosystems were, overall, a small source of carbon to the atmosphere equivalent to to 0.23±0.025 g C m,2 day,1. When considered separately, arable and grasslands were a source of, respectively, 0.68±0.022 and 1.28±0.026 g C m,2 day,1. Evergreen and deciduous forests were instead a sink of ,1.42±0.015 g C m,2 day,1. During the study period, forests offset approximately 3.5% of anthropogenic carbon emission estimates obtained from inventory data. Lacking of a robust validation, NEE values obtained with this method were compared with independent state of art estimates of the regional carbon balance that were obtained by applying a semi-empirical model of NEE driven by MODIS satellite fAPAR data. The comparison showed an acceptable matching for the carbon balance of forest that was a sink in both cases, while a much larger difference for arable and grassland was found. Those ecosystems were a sink for satellite-based estimates while they were a source for the combined aircraft and tower estimates. Possible causes of such differences are discussed and partly addressed. The importance of new methods for determining carbon balance at the regional scale, is outlined. [source] ORIGINAL ARTICLE: Extinction of the autochthonous small mammals of Mallorca (Gymnesic Islands, Western Mediterranean) and its ecological consequencesJOURNAL OF BIOGEOGRAPHY, Issue 6 2008Pere Bover Abstract Aim, To investigate the chronology, causes and consequences of the extinction of the autochthonous Pleistocene small mammals of Mallorca. Location, Mallorca (Gymnesic Islands, Balearics, Western Mediterranean). Methods, We have obtained the first direct 14C ages from the bone collagen of selected samples of two extinct endemic small mammals from Mallorca: the Balearic dormouse, Eliomys morpheus (Rodentia: Myoxidae) and the Balearic shrew, Asoriculus hidalgoi (Soricomorpha: Soricidae). We also present evidence for the absence of both endemics from the earliest Mallorcan archaeological sites and for the introduction of the garden dormouse, Eliomys quercinus, and the wood mouse, Apodemus sylvaticus. Combined information from direct dating of bone collagen of E. quercinus and A. sylvaticus and from cultural associations provides an adequate framework to establish the chronology of the faunal change and to compare it with the chronological information available on climatic change and the first arrival of humans on the islands. Results, The chronological record includes the latest evidence available for the survival of endemic species and the earliest introduction of small mammals into Mallorca. We present ,uncertainty periods for extinction' (UPEs) of both endemic mammals based on the chronology of their last occurrence and on the inferred timing of their extinction (restricted UPEs). Main conclusions, Possible causes for the extinction of autochthonous small mammals on Mallorca are discussed. Once we have discarded climatic causes, predation by invasive species, competition with newcomers and habitat deterioration, the introduction of diseases emerges as the most reasonable explanation for these extinctions. Based on the identification of changes in keystone species in Mallorcan ecosystems, we propose a tentative schedule of key ecological changes that have taken place over the past 5 millennia. [source] Possible causes of decreasing migratory ungulate populations in an East African savannah after restrictions in their seasonal movementsAFRICAN JOURNAL OF ECOLOGY, Issue 1 2010Margje M. Voeten Abstract In many areas in Africa, seasonal movements of migratory ungulates are restricted and their population numbers decline, for example in the Tarangire region, Tanzania. Here, agriculture restricts migration of ungulates to their wet season ranges. We investigated whether low forage quality or supply are possible causes of population decline of wildebeest and zebra when access to these wet season ranges is restricted and migratory herds have to reside in the dry season range year-round. We simulated grazing through a clipping experiment in the dry season range during the wet season. Clipping negatively affected forage supply and had a positive effect on forage quality by increasing proportions of live and leaf biomass as well as nutrient concentrations in the leaves. However, increase in forage quality in the dry season range due to grazing was not as such that requirements of wildebeest during the wet season, when females are lactating, could be met. We conclude that low forage quality in the dry season range during the wet season could cause the decrease in migratory ungulate populations in the Tarangire region. With this study, the necessity of protecting wet season ranges from expanding human activities to safeguard migratory systems is supported. Résumé Dans de nombreuses régions d'Afrique, les déplacements saisonniers des ongulés migrateurs sont entravés et leurs populations déclinent, comme par exemple dans la région de Tarangire, en Tanzanie. Ici, c'est l'agriculture qui limite la migration des ongulés vers les domaines qu'ils fréquentent en saison des pluies. Nous avons étudié si la mauvaise qualité ou la faible quantité du fourrage étaient des causes possibles du déclin des populations de gnous et de zèbres lorsque l'accès à leur domaine de saison des pluies est limité et que les troupeaux migrateurs doivent rester dans les domaines de saison sèche toute l'année. Nous avons simulé le pâturage en menant, en saison des pluies, une expérience de tonte dans l'aire fréquentée en saison sèche. Couper l'herbe avait un effet négatif sur l'apport de fourrage et avait un effet positif sur la qualité du fourrage parce que cela augmentait la proportion de biomasse vivante et de feuilles ainsi que la concentration de nutriments dans les feuilles. Cependant, augmenter par le pâturage la qualité du fourrage dans le domaine de saison sèche n'était pas suffisant pour satisfaire les besoins des gnous en saison des pluies, lorsque les femelles sont allaitantes. Nous concluons qu'en saison des pluies, la qualité médiocre du fourrage dans le domaine fréquenté en saison sèche pourrait causer la diminution des populations d'ongulés migrateurs dans la région de Tarangire. Cette étude conforte la nécessité de protéger les domaines fréquentés en saison des pluies contre l'expansion des activités humaines, afin de sauvegarder les systèmes migratoires. [source] Conservation status and causes of decline of the threatened New Zealand Long-tailed Bat Chalinolobus tuberculatus (Chiroptera: Vespertilionidae)MAMMAL REVIEW, Issue 2 2000Colin F. J. O'Donnell ABSTRACT Historical anecdotes and preliminary monitoring since 1990 indicate that New Zealand Long-tailed Bats (Chalinolobus tuberculatus, Vespertilionidae) are now rare or absent at many sites where formerly they were common. Chalinolobus tuberculatus appeared to be common throughout New Zealand in the 1800s but by 1900,30 it was becoming scarce in many districts. Formal surveys in the South Island since 1990 either failed to find C. tuberculatus, or recorded bats in low numbers. Of eight sites where transect counts were undertaken, bats were recorded frequently at two sites (45,66% of counts; Eglinton and Dart Valleys), rarely at four sites (2.4,10.7% of counts), and were not recorded at the remaining two sites despite considerable survey effort. Of 10 sites where stationary counts using automatic detector units were used, no C. tuberculatus were recorded in three areas (153 nights combined), they were found rarely at six sites (2.1,21.0% of nights; 461 nights combined) and were recorded commonly only in the Eglinton Valley (85% of 120 nights). Assertions that C. tuberculatus are ,common' and that the conservation status is ,secure' are questionable and this review supports suggestions that the species should be classed as ,Vulnerable'. Possible causes of decline have been suggested including clearance and logging of lowland forests, predation by introduced mammals and owls, competition for roost sites by introduced mammals, birds and wasps, and human interference and disturbance at roosting sites. However, authors' claims have all been speculative and unsubstantiated. There has been no research undertaken to quantify these claims, and this is required urgently. The results of these preliminary surveys provide a new baseline against which future population trends might be compared. Increased effort using standardized monitoring techniques, applied at a national level, is required to confirm the possible trends and to help identify the best sites where conservation managers may attempt to restore the population level. [source] Possible causes of morphological variation in an endemic Moroccan groundsel (Senecio leucanthemifolius var. casablancae): evidence from chloroplast DNA and random amplified polymorphic DNA markersMOLECULAR ECOLOGY, Issue 2 2003Max Coleman Abstract Genetic variation was assessed in Senecio leucanthemifolius var. casablancae (Compositae), a Moroccan Atlantic coast endemic, in order to examine possible causes of atypical leaf morphology in three populations south of the known range. Evidence for introgression from S. glaucus ssp. coronopifolius and/or divergence was investigated with molecular markers. Both random amplified polymorphic DNA (RAPD) and chloroplast (cp) DNA restriction fragment length polymorphism (RFLP) differentiated the species well. Some evidence that hybridization may have occurred between the two species was provided by cpDNA markers. However, biparentally inherited RAPD markers failed to provide any support for the hypothesis that intermediate leaf morphologies in atypical populations arose through hybridization. Consequently, they are most likely to have arisen via divergence caused by drift and/or selection. Genetic distances among populations of S. leucanthemifolius were significant in all but one case. Isolation by distance was indicated by a significant positive correlation between genetic and geographical distances (r = 0.68, P = 0.01, Mantel test). These results suggest that long-distance achene dispersal is rare, despite the presence of a well-developed pappus. The observed loss of pappus at achene maturity may explain this unexpected result. Due to the morphological distinction of var. casablancae from other varieties of S. leucanthemifolius, we suggest elevation to species rank and treatment of the atypical material at infraspecific rank. [source] Molecular systematics, biogeography and population structure of Neotropical freshwater needlefishes of the genus PotamorrhaphisMOLECULAR ECOLOGY, Issue 3 2000N. R. Lovejoy Abstract Phylogenetic relationships of populations and species within Potamorrhaphis, a genus of freshwater South American needlefishes, were assessed using mitochondrial cytochrome b sequences. Samples were obtained from eight widely distributed localities in the Amazon and Orinoco rivers, and represented all three currently recognized species of Potamorrhaphis. The phylogeny of haplotypes corresponded imperfectly to current morphological species identities: haplotypes from P. guianensis, the most widespread species, did not make up a monophyletic clade. Geography played a strong role in structuring genetic variation: no haplotypes were shared between any localities, indicating restricted gene flow. Possible causes of this pattern include limited dispersal and the effects of current and past geographical barriers. The haplotype phylogeny also showed a complex relationship between fishes from different river basins. Based on the geographical distribution of clades, we hypothesize a connection between the middle Orinoco and Amazon via rivers of the Guianas. More ancient divergence events may have resulted from Miocene alterations of river drainage patterns. We also present limited data for two other Neotropical freshwater needlefish genera: Belonion and Pseudotylosurus. Pseudotylosurus showed evidence of substantial gene flow between distant localities, indicating ecological differences from Potamorrhaphis. [source] Bladder control, urgency, and urge incontinence: Evidence from functional brain imaging,NEUROUROLOGY AND URODYNAMICS, Issue 6 2008Derek Griffiths Abstract Aim To review brain imaging studies of bladder control in subjects with normal control and urge incontinence; to define a simple model of supraspinal bladder control; and to propose a neural correlate of urgency and possible origins of urge incontinence. Methods Review of published reports of brain imaging relevant to urine storage, and secondary analyses of our own recent observations. Results In a simple model of normal urine storage, bladder and urethral afferents received in the periaqueductal gray (PAG) are mapped in the insula, forming the basis of sensation; the anterior cingulate gyrus (ACG) provides monitoring and control; the prefrontal cortex makes voiding decisions. The net result, as the bladder fills, is inhibition of the pontine micturition center (PMC) and of voiding, together with gradual increase in insular response, corresponding to increasing desire to void. In urge-incontinent subjects, brain responses differ. At large bladder volumes and strong sensation, but without detrusor overactivity (DO), most cortical responses become exaggerated, especially in ACG. This may be both a learned reaction to previous incontinence episodes and the neural correlate of urgency. The neural signature of DO itself seems to be prefrontal deactivation. Possible causes of urge incontinence include dysfunction of prefrontal cortex or limbic system, suggested by weak responses and/or deactivation, as well as abnormal afferent signals or re-emergence of infantile reflexes. Conclusions Bladder control depends on an extensive network of brain regions. Dysfunction in various parts may contribute to urge incontinence, suggesting that there are different phenotypes requiring different treatments. Neurourol. Urodynam. 27:466,474, 2008. © 2007 Wiley-Liss, Inc. [source] Spatial differences in acquisition of soil phosphate between two arbuscular mycorrhizal fungi in symbiosis with Medicago truncatulaNEW PHYTOLOGIST, Issue 2 2000F. A. SMITH Responses of Medicago truncatula to colonization by two arbuscular mycorrhizal fungi, Scutellospora calospora isolate WUM 12(2) and Glomus caledonium isolate RIS 42, were compared in the light of previous findings that the former fungus can be ineffective as a beneficial microsymbiont with some host plants. The plants were grown individually in two-compartment systems in which a lateral side arm containing soil labelled with 33P was separated from the main soil compartment by a nylon mesh that prevented penetration by roots but not fungal hyphae. Fungal inoculum was applied as a root,soil mixture in a band opposite the side arm. Nonmycorrhizal controls were set up similarly, without inoculum. There were harvests at 28, 35, 42 and 49 d. Both sets of mycorrhizal plants grew better than nonmycorrhizal plants and initially had higher concentrations of P in shoots and roots. Plants grown with S. calospora grew better than plants grown with G. caledonium, and this was associated with somewhat greater fungal colonization in terms of intraradical hyphae and numbers of arbuscules. Scutellospora calospora formed denser hyphae at root surfaces than G. caledonium. By 28 d there were extensive hyphae of both fungi in the side arms, and after 35 d S. calospora produced denser hyphae there than G. caledonium. Nevertheless, there was very little transfer of 33P via S. calospora to the plant at 28 d, and thereafter its transfer increased at a rate only c. 33% of that via G. caledonium. The results showed that plants colonized by S. calospora preferentially obtained P from sites in the main soil chamber relatively close to the roots, compared with plants colonized by G. caledonium. Hence formation of a highly beneficial arbuscular mycorrhizal symbiosis does not necessarily depend on development of hyphae at a distance from the roots or on large-scale translocation of P from distant sites. The results are discussed in relation to previous studies with compartmented systems that have involved the same fungi. Possible causes of the variable effects of S. calospora in symbiosis with different host plants are briefly assessed. Differences in spatial abilities of individual arbuscular mycorrhizal fungi to acquire P might have strong ecological implications for plant growth in soils low in P. [source] Insecticide toxicity and synergism by enzyme inhibitors in 18 species of pest insect and natural enemies in crucifer vegetable cropsPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 5 2007Gang Wu Abstract The toxicities of three enzyme inhibitors and their synergistic effects on four insecticides were studied by using the dry film method on field populations of 18 species of insects collected in Jianxin and Shanjie, China, from 2003 to 2005. Meanwhile, the inhibitory effects of these enzyme inhibitors on the activities of acetylcholinesterases (AChE), carboxyesterases (CarE) and glutathione- S -transferases (GST), in vivo, were also studied. In general, triphenyl phosphate (TPP) and diethyl maleate (DEM) showed low toxicities to six herbivorous pest insects, four ladybirds and eight parasitoids. Piperonyl butoxide (PB) exhibited low toxicities to the herbivorous pest insects and ladybirds, but high toxicities to the eight parasitoids. The tolerance to the insecticides in 11 pest insects and natural enemies was mainly associated with the tolerance to PB. PB showed the highest synergism on methamidophos, fenvalerate, fipronil and avermectin in nine species of pest insects and natural enemies. In general, TPP and DEM showed significant synergisms to these four insecticides in four parasitoid species. However, in contrast to their effects on the parasitoids, the synergistic effects of TPP and DEM on the four insecticides by TPP and DEM against four pest insects and one ladybird varied depending on the insect species and enzyme inhibitor. Activity of AChE, CarE or GST could be strongly inhibited, in vivo, by PB, TPP or DEM, depending on the insect species and enzyme inhibitors. From the results obtained in this study, mixed-function oxidase (MFO) was thought to play the most critical role in insect tolerances to the tested insecticides in the field. Low competition existed in the evolution of insecticide resistance in the field populations of parasitoids, as compared with herbivorous pest insects and ladybirds. Possible causes of the high synergistic effects of PB on the four classes of insecticides, based on multiattack on the activity of CarE, GST or AChE in the insect species, are also discussed. Copyright © 2007 Society of Chemical Industry [source] Patterns of respiration in Locusta migratoria nymphs when feedingPHYSIOLOGICAL ENTOMOLOGY, Issue 1 2000Scott M. Gouveia Summary Flow-through respirometry was used to investigate patterns of respiration of fifth-instar Locusta migratoria L. nymphs fed a chemically defined, synthetic food. Each animal was recorded for up to 2.7 h, during which they had access to food and water ad libitum, and at least one meal was taken. The start of feeding was coincident with a sudden and rapid rise in respiration. Both carbon dioxide (CO2) production and oxygen (O2) consumption rose, the traces for the two gasses showing a high degree of alignment. The end of a meal correlated with a sudden and rapid decrease in respiratory rate towards resting levels. When feeding was interrupted by an intra-meal pause, respiratory rate tended to drop marginally and then stabilize, before rising rapidly upon the resumption of feeding within the meal. Maximal rates of respiration during feeding represented a 3,4-fold increase over those at rest. Walking and climbing within the chamber were not associated with any noticeable change in respiratory rate above baseline. When locusts were quiescent between feeding episodes, respiration was steady and continuous, rather than discontinuous. Possible causes for large changes in respiration during feeding are discussed. [source] The Effect of Options on Stock Prices: 1973 to 1995THE JOURNAL OF FINANCE, Issue 1 2000Sorin M. Sorescu I show that the effect of option introductions on underlying stock prices is best described by a two-regime switching means model whose optimal switch date occurs in 1981. In accordance with previous studies, I find positive abnormal returns for options listed during 1973 to 1980. By contrast, I find negative abnormal returns for options listed in 1981 and later. Possible causes for this switch include the introduction of index options in 1982, the implementation of regulatory changes in 1981, and the possibility that options expedite the dissemination of negative information. [source] Simulation of the population dynamics and social structure of the Virunga mountain gorillasAMERICAN JOURNAL OF PRIMATOLOGY, Issue 4 2004Martha M. Robbins Abstract An agent-based model was developed to simulate the growth rate, age structure, and social system of the endangered mountain gorillas (Gorilla beringei beringei) in the Virunga Volcanoes region. The model was used to compare two types of data: 1) estimates of the overall population size, age structure, and social structure, as measured by six censuses of the entire region that were conducted in 1971,2000; and 2) information about birth rates, mortality rates, dispersal patterns, and other life history events, as measured from three to five habituated research groups since 1967. On the basis of the research-group data, the "base simulation" predicted a higher growth rate than that observed from the census data (3% vs. 1%). This was as expected, because the research groups have indeed grown faster than the overall population. Additional simulations suggested that the research groups primarily have a lower mortality rate, rather than higher birth rates, compared to the overall population. Predictions from the base simulation generally fell within the range of census values for the average group size, the percentage of multimale groups, and the distribution of females among groups. However, other discrepancies predicted from the research-group data were a higher percentage of adult males than observed, an overestimation of the number of multimale groups with more than two silverbacks, and an overestimated number of groups with only two or three members. Possible causes for such discrepancies include inaccuracies in the census techniques used, and/or limitations with the long-term demographic data set obtained from only a few research groups of a long-lived species. In particular, estimates of mortality and male dispersal obtained from the research groups may not be representative of the entire population. Our final simulation addressed these discrepancies, and provided a better basis for further studies on the complex relationships among individual life history events, group composition, population age structure, and growth rate patterns. Am. J. Primatol. 63:201,223, 2004. © 2004 Wiley-Liss, Inc. [source] Clonal genetic diversity and populational genetic differentiation in Phragmites australis distributed in the Songnen Prairie in northeast China as revealed by amplified fragment length polymorphism and sequence-specific amplification polymorphism molecular markersANNALS OF APPLIED BIOLOGY, Issue 1 2009M. Li Abstract Genetic variation within and between four naturally occurring Phragmites australis land populations, DBS, QG, SS1 and SS2 (named after locality), which colonise distinct habitats (different edaphic conditions) in the Songnen Prairie in northeast China, were investigated by amplified fragment length polymorphism (AFLP) and sequence-specific amplification polymorphism (S-SAP) markers. It was found that the selected primer combinations of both markers were highly efficient in revealing the inter-clonal genetic diversity and inter-populational genetic differentiation in P. australis from a molecular ecological perspective. Cluster analysis categorised the plants into distinct groups (DBS, QG and SS groups), which were in line with their localities, albeit the two SS group populations (SS1 and SS2) showed a lower degree of inter-populational differentiation. These results were strongly supported by multiple statistical analysis including Mantel's test, principal coordinate analysis, allocation test and analysis of molecular variance, which further suggested that gene flow, genetic drift and differences in as yet unidentified edaphic factors may all underpin the inter-clonal genetic diversity and inter-populational differentiation at the nucleotide sequence level. Analysis of intra-population clonal diversity also revealed that the QG population harboured a strikingly lower amount of within-population variation compared with those of the other three populations, presumably being caused by genetic drift and followed by physical and/or biological isolation. Homology analysis of a subset of population-specific or population-private AFLP and S-SAP bands suggested that regulatory genes and retroelements might play important roles in the ecological adaptation and differentiation of the P. australis populations. Possible causes for and implications of the extensive genetic variability in P. australis were discussed for its future genetic conservation and use in ecological revegetation. [source] Prospects for the Two-party System in a Pluralising Political WorldAUSTRALIAN JOURNAL OF PUBLIC ADMINISTRATION, Issue 2 2002Andrew Norton Political commentators argue that the major political parties are in decline. This article sets out evidence for this view: minor parties and independents securing 20 percent of the vote at federal elections, declining strength of voters' party identification, and issue movements playing a large role in setting the political agenda. Possible causes for these trends range from the political, such as policy failure, undermining traditional constituencies, and ignoring public opinion, to sociological forces, such as postmaterialism, individualism and serious disaffection. However, the article argues Labor and the Coalition will be the dominant political players for the foreseeable future. In most lower houses, the electoral system favours the major parties which on balance is a good thing. The major parties have taken concerns of interest groups into account, while balancing these against majority opinion. They simplify choice for an electorate only moderately interested in politics, and can be held accountable in a way minor parties and independents cannot. [source] A Possibilistic Petri Net Model for Diagnosing Cracks in RC StructuresCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 6 2003Kevin F. R. Liu PPN integrates Petri nets with possibilistic reasoning and maintains the advantages of both formalisms. Two major features of PPN include the possibilistic token to carry information to describe an object and its corresponding possibility and necessity measures, and four types of possibilistic transitions,inference, duplication, aggregation, and aggregation-duplication. A reasoning algorithm, based on possibilistic Petri nets, is also developed to execute PPN. The PPN model and the reasoning algorithm are further used to diagnose possible causes of cracking in RC structures, and three basic cases are considered to demonstrate the applicability of the approach. The reliability of the results is increased by explaining the diagnostic process through the movement of tokens. Moreover, the confidence level associated with each possible cause of concrete cracking can be used to determine the relevance of the diagnosis. [source] Bifid mandibular condyle: a case reportDENTAL TRAUMATOLOGY, Issue 3 2004Nur Hersek Abstract,,, A case of left bifid mandibular condyle (BMC) is reported in a 36-year-old female. The patient had a history of trauma in childhood. From the radiological examination, the left condyle was seen to have two anterioposteriorly situated heads. BMC is an extremely rare condition, where the condyle is duplicated or lobulated. The literature on BMC is reviewed, and possible cause of trauma and consequences of the anomaly are discussed. [source] Clarithromycin-induced hypomania in a child , a case reportACTA PSYCHIATRICA SCANDINAVICA, Issue 3 2010W. J. Baranowski Baranowski WJ. Clarithromycin-induced hypomania in a child , a case report. Objective:, We report here a child developing hypomania while treated with clarithromycin. Method:, Case report. Results:, A 3-year-old boy was treated for pneumonia with oral clarithromycin in monotherapy. The boy became somewhat hyperactive and irritable after the second dose. After the third dose he presented with psychomotor agitation, pressured speech, irritability, aggressive behaviour and insomnia. The antibiotic was identified as the only possible cause of the described clinical picture and was discontinued immediately. The hypomanic symptoms subsided gradually over 36 h. Conclusion:, Commonly-used medications can produce uncommon adverse reactions. Clinicians, especially general practitioners, pediatricians, as well as child and adolescent psychiatrists ought to be aware of such a possibility when evaluating a child with suddenly changed behaviour. [source] A new genus and species of basal actinopterygian fish from the Upper Devonian Gogo Formation of Western AustraliaACTA ZOOLOGICA, Issue 2009Brian Choo Abstract A new basal actinopterygian, Gogosardina coatesi gen. et sp. nov., is described from the Upper Devonian Gogo Formation of the Canning Basin, Western Australia. The new taxon is known from four prepared specimens that display the typical exceptional preservation of fossil vertebrates from the region. Gogosardina gen. nov. possesses a series of four small postrostrals, no surangular and a highly gracile body covered with over 140 vertical rows of very small scales, all ornamented with separate horizontal ganoine ridges. One specimen contains conodont elements lodged among the branchial arches, indicating dietary habits and a possible cause of death. [source] Folate deficiency in human peripheral blood lymphocytes induces chromosome 8 aneuploidy but this effect is not modified by riboflavinENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 1 2010Juan Ni Abstract Chromosome 8 aneuploidy is a common event in certain cancers but whether folate (F) deficiency induces chromosome 8 aneuploidy is not known. Furthermore the impact of riboflavin (R) deficiency, which may alter activity of a key enzyme in folate metabolism, on these events is unknown. Therefore, the aim of our research was to test the following hypotheses: (a) F deficiency induces chromosome 8 aneuploidy; (b) chromosome 8 aneuploidy is affected by F deficiency to a similar degree as chromosome 17 and (c) R deficiency aggravates the risk of aneuploidy caused by F deficiency. These hypotheses were tested in long-term cultures of lymphocytes from twenty female healthy volunteers (aged 30,48 years). Lymphocytes were cultured in each of the four possible combinations of low (L) and high (H) F (LF, 20 nmol/L, HF 200 nmol/L, respectively) and L and H R (LR 1 nmol/L, HR 500 nmol/L, respectively) media (LFLR, LFHR, HFLR, HFHR) for 9 days. Chromosomes 8 and 17 aneuploidy was measured in mononucleated (MONO) and cytokinesis-blocked binucleated (BN) cells using dual-color fluorescence in situ hybridization (FISH) with fluorescent centromeric probes specific for chromosomes 8 and 17. Culture in LF media (LFLR or LFHR) induced significant and similar increases in frequencies of aneuploidy of chromosomes 8 and 17 (P < 0.001) relative to culture in HF media (HFLR or HFHR). There was no significant effect of R concentration on aneuploidy frequency for either chromosome. We conclude that F deficiency is a possible cause of chromosome 8 aneuploidy. Environ. Mol. Mutagen. 2010. © 2009 Wiley-Liss, Inc. [source] Faecal shedding and serological cross-sectional study of Lawsonia intracellularis in horses in the state of Minas Gerais, BrazilEQUINE VETERINARY JOURNAL, Issue 6 2009C. V. Guimarães-Ladeira Summary Reason for performing the study: Proliferative enteropathy, caused by the intracellular bacterium Lawsonia intracellularis, has been described in horses in Australia, the USA, Canada and European countries but has not been reported in Latin America. The prevalence of the disease in horses worldwide is unknown. Objective: To evaluate the presence of subclinical L. intracellularis infection in horses in the state of Minas Gerais, Brazil. Methods: A longitudinal study using serology and PCR for detecting antibodies (IgG) and shedding of L. intracellularis in faecal samples, respectively, was conducted using a total of 223 horses from 14 different horse farms in Minas Gerais, and from the Veterinary School of UFMG equine herds in Minas Gerais. The immunoperoxidase technique in glass slides was used as the serological test. Results: Twenty-one horse sera had immunoglobulin G titres of 1:60 and were considered positive. The PCR technique in faeces for L. intracellularis DNA identified 7 horses as faecal shedders. Horses shedding the organism appeared healthy, indicating that subclinical infection of L. intracellularis occurred in the horses. Conclusion: Seropositivity and detection of faecal shedding of L. intracellularis indicates the presence of the agent in the equine population in Minas Gerais. Potential relevance: Results of this study should alert clinicians in countries where proliferative enteropthy in horses has not been reported to consider this disease as a possible cause of enteric disease. [source] Lysosomal storage disease in Sida carpinifolia toxicosis: an induced mannosidosis in horsesEQUINE VETERINARY JOURNAL, Issue 5 2003A. P. LORETTI Summary Reasons for performing study: This study reports a neurological disease unrecognised until now in ponies in southern Brazil. Hypothesis: Epidemiological data strongly suggests that the ingestion of Sida carpinifolia is involved in the aetiology. We tested the hypothesis that it is an acquired lyosomal storage disease. Methods: Following the death of 3 ponies, all ponies from the premises were closely monitored; epidemiological data and clinical findings carefully recorded. Fragments of several organs, including CNS, were fixed in neutral formalin and embedded in paraffin-wax. Sections were stained with haematoxylin and eosin. Representative sections of the cerebellum and trigeminal ganglia were submitted to lectin histochemical procedures. Results: The neurological disorder, characterised by stiff gait, muscle tremors, abdominal pain and death, was observed on a farm with 3 hectares of pasture. Three of 11 ponies died 15,20 days after they had been introduced into a new paddock heavily infested by the plant Sida carpinifolia. No significant gross lesions were observed. The main histological findings included multiple cytoplasmatic vacuoles in swollen neurones in the brain, cerebellum, spinal cord, autonomic ganglia (trigeminal and celiac ganglia), and submucosal and myenteric plexus of the intestines. In the kidneys, there was marked vacuolation of the proximal convoluted tubular cells. Sections of cerebellum and trigeminal ganglion were submitted to lectin histochemistry. The vacuoles in different cerebellar and ganglion cells reacted strongly to the following lectins: Concanavalia ensiformis, Triticum vulgaris and succinylated- Triticum vulgaris. Conclusions: The pattern of staining coincides with that of both swainsonine toxicosis and inherited mannosidosis reports. The histopathological changes were similar to those described in S. carpinifolia spontaneous and experimental poisoning in goats. This disease seems to be similar to Swainsona, Oxytropis and Astragalus toxicosis. Potential relevance: S. carpinifolia should be evaluated as a possible cause in the diagnosis of equine neuropathies. [source] Abnormal cardiovascular responses to carotid sinus massage also occur in vasovagal syncope , implications for diagnosis and treatmentEUROPEAN JOURNAL OF NEUROLOGY, Issue 8 2010A. M. Humm Background and purpose:, Carotid sinus massage (CSM) is commonly used to identify carotid sinus hypersensitivity (CSH) as a possible cause for syncope, especially in older patients. However, CSM itself could provoke classical vasovagal syncope (VVS) in pre disposed subjects. Methods:, Retrospective analysis of CSM, cardiovascular autonomic function tests (including tilt table testing) and medical history in 388 patients with recurrent syncope to identify and characterize patients in whom an abnormal response to CSM was more likely to reflect VVS than CSH. Results:, CSM was abnormal in 79 patients. In 53 patients (77.2 ± 8.7 years), CSH was the likely cause of syncope. VVS was the more likely diagnosis in 26 younger patients (59.7 ± 12.6 years) with longstanding syncope from youth, in whom fear or pain was as a trigger; 7/26 suffered from intense chronic or intermittent neck pain and one exacerbation of syncopal attacks followed a physical and emotional trauma to the neck. In VVS, 4/26 had spontaneous VVS during head-up tilt, another six after venepuncture (performed in 17/26). In 6/26, the abnormal response to CSM was delayed, occurring 62.8 ± 28.4 s after completion of CSM. The response to CSM was predominantly of the mixed type (20/26) and abnormal on both sides in 14/26. Conclusions:, An abnormal response to CSM may not indicate syncope caused by CSH and needs to be considered in the light of the patient's age, duration of syncopal episodes and detailed history of provocative stimuli. Differentiating CSH from VVS with an abnormal response to CSM has various implications from advice on driving to treatment strategies. [source] DNA methylation variation in cloned miceGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 2 2001Jun Ohgane Abstract Summary: Mammalian cloning has been accomplished in several mammalian species by nuclear transfer. However, the production rate of cloned animals is quite low, and many cloned offspring die or show abnormal symptoms. A possible cause of the low success rate of cloning and abnormal symptoms in many cloned animals is the incomplete reestablishment of DNA methylation after nuclear transfer. We first analyzed tissue-specific methylation patterns in the placenta, skin, and kidney of normal B6D2F1 mice. There were seven spots/CpG islands (0.5% of the total CpG islands detected) methylated differently in the three different tissues examined. In the placenta and skin of two cloned fetuses, a total of four CpG islands were aberrantly methylated or unmethylated. Interestingly, three of these four loci corresponded to the tissue-specific loci in the normal control fetuses. The extent of aberrant methylation of genomic DNA varied between the cloned animals. In cloned animals, aberrant methylation occurred mainly at tissue-specific methylated loci. Individual cloned animals have different methylation aberrations. In other words, cloned animals are by no means perfect copies of the original animals as far as the methylation status of genomic DNA is concerned. genesis 30:45,50, 2001. © 2001 Wiley-Liss, Inc. [source] The role of static stress transfer in mining induced seismic events occurrence, a case study of the Rudna mine in the Legnica-Glogow Copper District in PolandGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 2 2010B. Orlecka-Sikora SUMMARY Seismicity accompanying mining exploitation results from changes in the stress field in the rock mass near the mining excavations caused by human activity. Many studies of the temporal and spatial distribution of mining induced seismicity have provided evidence for interrelations among events. Although a variety of techniques have been applied to quantify the interdependences of mining induced seismic events, the physical mechanism of interactions has not been unequivocally identified. Based on the premise that one possible cause of interactions among seismic events can be static stress transfer, we have verified statistically the role of Coulomb stress transfer in the generation process of mining induced seismicity using a series of seismic events that occurred in the Rudna mine in the Legnica-G,ogów Copper District in Poland. We quantify the triggering and inhibiting effect by the proportion of events in the series, whose locations are consistent with the stress increased and stress decreased zones, respectively. We have found that more than 60 per cent of the analysed seismic events occurred in areas where stress was enhanced due to the occurrence of previous events. The statistical significance of these results is tested by comparing them with the same proportions obtained for 2000 random permutations of the original series of events. The test has indicated that the locations in positive stress changes areas are preferred statistically significantly when the stress changes exceed 0.05 bar. This result turns out to be robust to the errors of the nodal planes determination. [source] | ||||||||||||||||||||||||||||||||||||||||||||||