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Considerable Variability (considerable + variability)
Selected AbstractsThe training stimulus experienced by the leg muscles during cycling in humansEXPERIMENTAL PHYSIOLOGY, Issue 6 2009Jamie S. McPhee Considerable variability exists between people in their health- and performance-related adaptations to conventional endurance training. We hypothesized that some of this variability might be due to differences in the training stimulus received by the working muscles. In 71 young sedentary women we observed large variations in the ratio of one-leg cycling muscle aerobic capacity to two-leg cycling whole-body maximal oxygen uptake (; Ratio1:2; range 0.58,0.96). The variability in Ratio1:2 was primarily due to differences between people in one-leg (r= 0.71, P < 0.0005) and was not related to two-leg (r= 0.15, P= 0.209). Magnetic resonance imaging (n= 30) and muscle biopsy sampling (n= 20) revealed that one-leg was mainly determined by muscle volume (r= 0.73, P < 0.0005) rather than muscle fibre type or oxidative capacity. A high one-leg was associated with favourable lipoprotein profiles (P= 0.033, n= 24) but this was not the case for two-leg . Calculations based on these data suggest that conventional two-leg exercise at 70% requires subjects with the lowest Ratio1:2 to work their legs at 60% of single-leg , whilst those with the highest Ratio1:2 work their legs at only 36% of maximum. It was concluded that endurance training carried out according to current guidelines will result in highly variable training stimuli for the leg muscles and variable magnitudes of adaptation. These conclusions have implications for the prescription of exercise to improve health and for investigations into the genetic basis of muscle adaptations. [source] Are All Trauma Centers Created Equally?ACADEMIC EMERGENCY MEDICINE, Issue 7 2010A Statewide Analysis ACADEMIC EMERGENCY MEDICINE 2010; 17:701,708 © 2010 by the Society for Academic Emergency Medicine Abstract Objectives:, Prior work has shown differences in mortality at different levels of trauma centers (TCs). There are limited data comparing mortality of equivalently verified TCs. This study sought to assess the potential differences in mortality as well as discharge destination (discharge to home vs. to a rehabilitation center or skilled nursing facility) across Level I TCs in the state of Ohio. Methods:, This was a retrospective, multicenter, statewide analysis of a state trauma registry of American College of Surgeons (ACS)-verified Level I TCs from 2003 to 2006. All adult (>15 years) patients transferred from the scene to one of the 10 Level I TCs throughout the state were included (n = 16,849). Multivariable logistic regression models were developed to assess for differences in mortality, keeping each TC as a fixed-effect term and adjusting for patient demographics, injury severity, mechanism of injury, and emergency medical services and emergency department procedures. Outcomes included in-hospital mortality and discharge destination (home vs. rehabilitation center or skilled nursing facility). Adjusted odds ratios (ORs) for each TC were also calculated. Results:, Considerable variability existed in unadjusted mortality between the centers, from 3.8% (95% confidence interval [CI] = 3.7% to 3.9%) to 24.2% (95% CI = 24.1% to 24.3%), despite similar patient characteristics and injury severity. Adjusted mortality had similar variability as well, ranging from an OR of 0.93 (95% CI = 0.47 to 1.84) to an OR of 6.02 (95% CI= 3.70 to 9.79). Similar results were seen with the secondary outcomes (discharge destination). Conclusions:, There is considerable variability in the mortality of injured patients at Level I TCs in the state of Ohio. The patient differences or care processes responsible for this variation should be explored. [source] Variability in human embryonic development and its implications for the susceptibility to environmental teratogenesisBIRTH DEFECTS RESEARCH, Issue 8 2009Kohei Shiota Abstract Considerable variability is observed in the size and developmental stage among human embryos at a given gestational age, suggesting that prenatal development does not proceed at the same speed in every embryo. Such variability in embryonic development seems to occur in many (probably all) animal species, and is probably a normal "biologic" phenomenon to some extent. In the case of humans, some other factors (e.g., maternal memory bias, difficulty in assessing the timing of ovulation and fertilization) make it more difficult to assess the developmental stage of embryos in utero. Such facts related to human embryonic development should be taken into account when the teratogenic risk of a human embryo is considered. Birth Defects Research (Part A), 2009. © 2009 Wiley-Liss, Inc. [source] Spontaneous apoptosis in chronic lymphocytic leukemia and its relationship to clinical and cell kinetic parametersCYTOMETRY, Issue 6 2001Gislaine B. Oliveira Abstract Chronic lymphocytic leukemia (CLL) presents considerable variability in clinical presentation as well as in its evolution. In contrast to the inhibition of apoptosis in vivo, spontaneous apoptosis after short-term culture occurs. We studied the degree of this apoptosis in vitro, and its interactions with several clinical and laboratory parameters. Apoptosis was measured by the annexin V technique. Proliferation rate was evaluated by the AgNOR (nucleolar organizer regions) technique. There were inverse correlations between the percentage of annexin V-positive cells and peripheral lymphocyte count (r = - 0.49), Rai stage (r = - 0.40), Binet stage (r = - 0.50), TTM (total tumor mass score; r = - 0.51), and percentage of cells with one AgNOR cluster (r = - 0.45). Direct correlations were found with hemoglobin values ( r = 0.34) and platelet counts (r = 0.52). The number of CD8-positive cells showed a correlation with peripheral lymphocyte count (r = 0.49). When this variable was held constant, a correlation was detected between CD8-positive cells and staging (r = -0.47), TTM (r = - 0.42), and platelet count (r = 0.67). CD4-positive lymphocytes presented a correlation only with CD8-positive lymphocytes. In a cluster analysis, it was possible to create three groups of patients with different apoptosis rates using the TTM and AgNOR values. We conclude that, with the progression of the disease, together with the increase of tumor mass and proliferation rate, there is a decrease in the suceptibility to apoptosis. Cytometry (Comm. Clin. Cytometry) 46:329,335, 2001. © 2001 Wiley-Liss, Inc. [source] Language and communication development in down syndromeDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 1 2007Joanne E. Roberts Abstract Although there is considerable variability, most individuals with Down syndrome have mental retardation and speech and language deficits, particularly in language production and syntax and poor speech intelligibility. This article describes research findings in the language and communication development of individuals with Down syndrome, first briefly describing the physical and cognitive phenotype of Down syndrome, and two communication related domains,hearing and oral motor skills. Next, we describe language development in Down syndrome, focusing on communication behaviors in the prelinguistic period, then the development of language in children and adolescents, and finally language development in adults and the aging period. We describe language development in individuals with Down syndrome across four domains: phonology, semantics, syntax, and pragmatics. Wethen suggest strategies for intervention and directions for research relating to individuals with Down syndrome. © 2007 Wiley-Liss, Inc. MRDD Research Reviews 2007;13:26,35. [source] Antidepressant combinations: epidemiological considerationsACTA PSYCHIATRICA SCANDINAVICA, Issue 2005L. F. Agüera Objective:, To evaluate the treatment options in patients who do not respond appropriately to a single antidepressant alone. Method:, The medical literature was reviewed. Results:, A number of strategies are available if a patient fails to respond adequately to initial antidepressant treatment, including the combination with another psychoactive drug. Evidence published to date appears to suggest that benzodiazepines are the drugs most frequently combined with antidepressants. The combination of two antidepressants together is less common, occurring in approximately 5,15% of cases showing a poor initial response. The key figures involved in such co-prescription are psychiatrists. Conclusion:, There appears to be considerable variability in the data concerning combined prescription of antidepressants, with differences arising depending on the type of physician, the type of patient or illness and the geographical area. It is also unclear how closely research findings parallel with what doctors do in everyday practice. [source] Temporal lobe epilepsy surgery and the quest for optimal extent of resection: A reviewEPILEPSIA, Issue 8 2008Johannes Schramm Summary The efficacy of surgery to treat drug-resistant temporal lobe epilepsy (TLE) has been demonstrated in a prospective randomized trial. It remains controversial which resection method gives best results for seizure freedom and neuropsychological function. This review of 53 studies addressing extent of resection in surgery for TLE identified seven prospective studies of which four were randomized. There is considerable variability between the intended resection and the volumetrically assessed end result. Even leaving hippocampus or amygdalum behind can result in seizure freedom rates around 50%. Most authors found seizure outcome in selective amygdalohippocampectomy (SAH) to be similar to that of lobectomy and there is considerable evidence for better neuropsychological outcome in SAH. Studies varied in the relationship between extent of mesial resection and seizure freedom, most authors finding no positive correlation to larger mesial resection. Electrophysiological tailoring saw no benefit from larger resection in 6 of 10 studies. It must be concluded that class I evidence concerning seizure outcome related to type and extent of resection of mesial temporal lobe structures is rare. Many studies are only retrospective and do not use MRI volumetry. SAH appears to have similar seizure outcome and a better cognitive outcome than TLR. It remains unclear whether a larger mesial resection extent leads to better seizure outcome. [source] Distribution and structure of the initial dental enamel formed in incisors of young wild-type and Tabby miceEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 6 2009Amer Sehic Mouse incisor enamel can be divided into four layers: an inner prism-free layer; an inner enamel with prism decussation; outer enamel with parallel prisms; and a superficial prism-free layer. We wanted to study how this complex structural organization is established in the very first enamel formed in wild-type mice and also in Tabby mice where enamel coverage varies considerably. Unworn incisors from young female wild-type and Tabby mice were ground, etched, and analyzed using scanning electron microscopy. In both wild-type and Tabby mice, establishment of the enamel structural characteristics in the initially formed enamel proceeded as follows, going from the incisal tip in an apical direction: (i) a zone with prism-free enamel, (ii) a zone with occasional prisms most often inclined incisally, and (iii) a zone where prism decussation was gradually established in the inner enamel. The distribution of enamel in Tabby mice exhibited considerable variability. The sequence of initial enamel formation in mouse incisors mimics development from a primitive (prism-free) structure to an evolved structure. It is suggested that genes controlling enamel distribution are not associated with genes controlling enamel structure. The control of ameloblast configuration, life span, organization in transverse rows, and movement is important for establishing the characteristic mature pattern of mouse incisor enamel. [source] Population variation in Persicaria salicifolia (Brouss. ex Willd.) Assenov (Polygonaceae) in NigeriaFEDDES REPERTORIUM, Issue 7-8 2002A. E. Ayodele Dr. Study of six living population samples and herbarium specimens of Persicaria salicifolia from Nigeria revealed considerable variability in vegetative and floral characters. Two subspecies, one of which is a new one (subsp. nova, p. 516), are recognised. Experimental cultivation showed that the combination of distinguishing characters for each subspecies remains intact under uniform conditions in the botanical nursery. Variabilität der Population von Persicaria salicifolia (Brouss. ex Willd.) Assenov (Polygonaceae) in Nigeria Studien an sechs lebenden Populationsproben und Herbar-Proben von Persicaria salicifolia aus Nigeria erbrachten eine beachtliche Variabilität der vegetativen und floralen Eigenschaften. Zwei Unterarten, eine von ihnen neu (subsp. nova) wurden verzeichnet. Kulturversuche zeigten, dass die Kombination der kennzeichnenden Merkmale jeder Unterart unter gleichen Bedingungen in einer botanischen Anzucht unverändert bleiben. [source] Metschnikowia arizonensis and Metschnikowia dekortorum, two new large-spored yeast species associated with floricolous beetlesFEMS YEAST RESEARCH, Issue 2 2002Marc-André Lachance Abstract Two new haplontic heterothallic species of Metschnikowia were discovered in flowers and associated beetles. Metschnikowia arizonensis was recovered from flowers of cholla cactus (Opuntia echinocarpa) and a specimen of Carpophilus sp. (Coleoptera: Nitidulidae) found in these flowers, in Arizona. Metschnikowia dekortorum was isolated in specimens of the nitidulid beetle Conotelus sp. captured in flowers of two species of Ipomoea in northwestern Guanacaste Province, Costa Rica. The sexual cycle of these yeasts is typical of the large-spored Metschnikowia species, but the asci and spores are intermediate in size between these and other members of the genus. The physiology is consistent with that of most Metschnikowia species except that both species fail to utilize lysine as sole nitrogen source. Also, M. arizonensis utilizes fewer carbon compounds than most species and exhibits considerable variability among strains at this level. Partial ribosomal DNA large-subunit (D1/D2) sequences suggest that M. arizonensis and M. dekortorum are moderately related sister species whose positions are intermediate between the large-spored species Metschnikowia and Metschnikowia hibisci. The type cultures are: M. arizonensis, strains UWO(PS)99-103.3.1=CBS 9064=NRRL Y-27427 (h+, holotype) and UWO(PS)99-103.4=CBS 9065=NRRL Y-27428 (h,, isotype); and M. dekortorum, strains UWO(PS)01-142b3=CBS 9063=NRRL Y-27429 (h+, holotype) and UWO(PS)01-138a3=CBS 9062=NRRL Y-27430 (h,, isotype). [source] Reproductive ecology of DrosophilaFUNCTIONAL ECOLOGY, Issue 5 2008T. A. Markow Summary 1Species of the genus Drosophila reproduce in a wide range of different resources, including fruits, sap, flowers, mushrooms and cacti. Drosophila species and their resources also exhibit considerable variability in geographic distribution. 2Habitat and resource differences pose enormous challenges for Drosophila species. Host chemistry may include highly toxic compounds and breeding sites may be characterized by extreme abiotic conditions such as high and/or low temperature and humidity. 3Drosophila reproductive biology, in terms of morphology, physiology, and behaviour, is as variable among Drosophila species as is their resource use. In some species, adults are ready to reproduce upon emergence, whereas one sex or the other in other species may require weeks to become sexually mature. 4Already a robust system for transmission and population genetic studies, the sequencing of the genomes of 12 diverse Drosophila species now brings the power of genomics to investigators wishing to understand the functional aspects of Drosophila ecology [source] Explaining isotope trophic-step fractionation: why herbivorous fish are differentFUNCTIONAL ECOLOGY, Issue 6 2007A. C. MILL Summary 1An assumed constant trophic fractionation of 15N/14N between consumer and diet (usually 3·4 for diet,muscle tissue differences) allows inferences to be made about feeding interactions and trophic level in food web studies. However, considerable variability surrounds this constant, which may conceal subtle differences about the trophodynamics of consumers. 2The feeding ecologies of herbivores and carnivores differ in terms of diet quality (in C : N terms) and food processing mechanisms, which may affect fractionation. 3We present a new model that explores how consumer feeding rates, excretion rates and diet quality determine the 15N/14N ratios in the consumer's tissues and hence influence the magnitude of trophic fractionation. 4Three herbivorous reef fish Acanthurus sohal, Zebrasoma xanthurum and Pomacentrus arabicus were chosen as study organisms. Empirical estimates of diet,tissue stable isotope fractionation were made in the field, and model parameters were derived from feeding observations and literature data. 5The trophic fractionation values of A. sohal, Z. xanthurum and P. arabicus were 4·69, 4·47 and 5·25, respectively, by empirical measurement, and 4·41, 4·30 and 5·68, respectively, by model, indicating that herbivores have a higher trophic fractionation than the currently accepted value of 3·4. 6The model was most sensitive to the excretion rate, which may differ between herbivores and carnivorous animals. This model is the first to determine stable isotope signatures of a consumer's diet mixture without applying a constant fractionation value. [source] The surface archaeological record in arid Australia: Geomorphic controls on preservation, exposure, and visibilityGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 2 2009Patricia C. Fanning The conventional approach to assessing the archaeological record in most parts of the world involves a combination of excavation of stratified deposits and extensive survey of surface deposits. Although widely applied in Australia, in both research-based and management archaeology, the method does not conform well to the nature of the surface archaeological record here. Over much of semi-arid and arid Australia, archaeological "sites" are, in fact, accretion phenomena that are not easily interpreted as the outcome of short-term behavioral events. Using results from twelve years of geoarchaeological research in western New South Wales, we demonstrate that there is considerable variability in landsurface age, and hence the "availability" of archaeological surfaces, over relatively short distances. Therefore, it cannot be assumed that stone artifact deposits, for example, that appear to be similar in character are of similar age. Data are also presented that demonstrate that the presence of artifacts on the surface, their apparent absence in sediments buried beneath the surface, and the apparent recent ubiquity of the archaeological record are all a function of geomorphic processes that, at the same time, expose some artifact deposits at the surface and erode and bury others amid large volumes of sediment. Interpreting the surface artifact record within a spatial and temporal geomorphic framework is crucial to understanding the past human behavior that the artifact deposits represent. © 2009 Wiley Periodicals, Inc. [source] Use of pharmacokinetics in the coagulation factor treatment of patients with haemophiliaHAEMOPHILIA, Issue 6 2005A. D. Shapiro Summary., Dosing decisions for replacement coagulation factors in patients with haemophilia should be made on an individual patient basis, with the required dose dependent on factors including the clinical situation, the severity of the factor deficiency, and the location and extent of bleeding. Moreover, there is considerable variability in the pharmacokinetics of coagulation products that needs to be considered; in particular, with both factor (F) IX and FVIII products, there is considerable inter-patient variability in in vivo recovery and terminal half-life values. In the present report, we provide a practical guide to calculating and applying pharmacokinetic parameters relevant to the optimal dosing of coagulation products. We discuss the conduct of a pharmacokinetic study in an individual patient, how to calculate pharmacokinetic values from raw data and clinical situations where an individual pharmacokinetic study is helpful. We highlight the importance of considering an individual pharmacokinetic study in all patients starting a new coagulation product. [source] HPV triage testing or repeat Pap smear for the management of atypical squamous cells (ASCUS) on Pap smear: is there evidence of process utility?HEALTH ECONOMICS, Issue 5 2008Kirsten Howard Abstract A two-stage standard gamble was used to evaluate women's preferences for alternative managements of atypical squamous cells of undermined significance (ASCUS) on Pap smear (repeat Pap smear compared with immediate HPV test), and to test for the evidence of process utility. Women's utilities for the health state scenarios were clustered towards the upper end of the 0,1 scale with considerable variability in women's preferences. There was evidence of process utility, with immediate human papillomavirus (HPV) testing strategies having lower valuations than repeat Pap smear, where the clinical outcome was the same. Mean (95% CI) utilities for HPV testing (negative test) followed by resolution were 0.9967 (0.9957,0.9978) compared with repeat Pap smear followed by resolution: 0.9972 (0.9964,0.9980). Mean (95% CI) utilities for immediate HPV testing (positive test), followed by colposcopy, biopsy and treatment were 0.9354 (0.8544,1.0) compared with repeat Pap smear followed by colposcopy, biopsy and treatment: 0.9656 (0.9081,1.0). Our results add to the existing evidence that the impact of healthcare interventions on well-being is not limited to the effect of the intervention on the health outcomes expected from the intervention; process of care can have quality of life implications for the individual. A modelled application of trial-based data will allow characterisation of the true population costs, benefits, risks and harms of alternative triage strategies and subsequent policy implications thereof. Copyright © 2007 John Wiley & Sons, Ltd. [source] Changes in clutch size, brood size and numbers of nesting Squacco Herons Ardeola ralloides over a 32-year period in the Camargue, southern FranceIBIS, Issue 1 2001HEINZ HAFNER Changes in numbers of nesting pairs, clutch size, and brood size of Squacco Herons Ardeola ralloides in the Camargue, southern France were analysed over a 32-year period. The annual numbers of breeding pairs [average 84 pairs pL 30 sd, n = 32 years) exhibited a possible increasing trend, but with considerable variability. This variability is associated with local spring rainfall, which may influence the available surface area of their preferred freshwater habitats. In contrast to population size, clutch size decreased substantially in recent years. Our data do not provide a causal explanation for this change in clutch size, although the reduction temporally corresponds with increasing rice cultivation and with a dramatic increase in the number of Cattle Egrets Bubulcus ibis in the Camargue. [source] Private speech: a study of language for thought in the collaborative interaction of language learnersINTERNATIONAL JOURNAL OF APPLIED LINGUISTICS, Issue 1 2004Frederick J. DiCamilla This article analyzes the speech of English-speaking college students of Spanish working in pairs to produce compositions in Spanish. Although there was considerable variability in the frequency of private speech from one dyad to another, the main goal of the study was to analyze those instances of private speech that could be clearly identified by both linguistic and paralinguistic evidence. Eight such excerpts are analyzed and discussed here. The analysis reveals that private speech of the participants facilitated two fundamental cognitive operations: focusing of attention and the creation of psychological distance. That is, private speech enabled the participants to concentrate on the task at crucial moments and to distance themselves from the problems they encountered, thereby achieving a perspective that in turn helped them to gain control in the performance of the task. It is argued that private speech that occurs in a social context can be identified and analyzed, and ultimately distinguished from social speech. [source] Methodological approaches in the assessment of interferon-alfa-induced depression in patients with chronic hepatitis C , a critical reviewINTERNATIONAL JOURNAL OF METHODS IN PSYCHIATRIC RESEARCH, Issue 4 2007Arne Schäfer Abstract In recent years, research on interferon (IFN)-induced depressive symptoms in antivirally treated patients suffering from chronic hepatitis C (CHC) has considerably intensified. Profound scientific knowledge of this complication is of great relevance with regard to adherence, compliance, and premature therapy discontinuation. Presently, there is considerable variability of both, the frequency and extent of IFN-induced depression reported in different cohorts of patients. The aim of the presented study was to systematically review recent literature of research within this field; and particularly (1) to identify to what extent methodological bias contributed to inconsistent results in different studies, (2) to critically appraise methods and results of studies published so far, and (3) to suggest directions for future work, especially with respect to alternative and improved methodological approaches. The results of this critical review suggest that the variability of findings seem to be largely due to different study populations, treatment regimens, methodological approaches, and sometimes arbitrary or at least poorly defined choice of screening instruments for depression, particularly criteria for clinically relevant depression (cut-off criteria). Study designs and methodological approaches to investigate IFN-alfa-induced depression in patients with CHC have been incoherent. Future research in this field needs agreement on the use of standardized assessment of IFN-induced depression in CHC. Furthermore, objective criteria and guidelines for the treatment of IFN-induced depression in these patients are needed in clinical practice. Copyright © 2008 John Wiley & Sons, Ltd. [source] Meta-Analysis of Psychosocial Interventions for Caregivers of People with DementiaJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 5 2003FRACP, FRANZCP, Henry Brodaty MD OBJECTIVES: To review published reports of interventions for caregivers (CGs) of persons with dementia, excluding respite care, and provide recommendations to clinicians. DESIGN: Meta-analytical review. Electronic databases and key articles were searched for controlled trials, preferably randomized, published in English from 1985 to 2001 inclusive. Thirty studies were located and scored according to set criteria, and the interventions' research quality and clinical significance were judged. SETTING: Home or noninstitutional environment. PARTICIPANTS: Informal CGs,persons providing unpaid care at home or in a noninstitutional setting. MEASUREMENTS: The primary measures were psychological morbidity and burden. Other varied outcome measures such as CG coping skills and social support were combined with measures of psychological distress and burden to form a main outcome measure. RESULTS: The quality of research increased over the 17 years. Results from 30 studies (34 interventions) indicated, at most-current follow-up, significant benefits in caregiver psychological distress (random effect size (ES) = 0.31; 95% confidence interval (CI) = 0.13,0.50), caregiver knowledge (ES = 0.51; CI = 0.05,0.98), any main caregiver outcome measure (ES = 0.32; CI = 0.15,0.48), and patient mood (ES = 0.68; CI = 0.30,1.06), but not caregiver burden (ES = 0.09; CI = ,0.09,0.26). There was considerable variability in outcome, partly because of differences in methodology and intervention technique. Elements of successful interventions could be identified. Success was more likely if, in addition to CGs, patients were involved. Four of seven studies indicated delayed nursing home admission. CONCLUSION: Some CG interventions can reduce CG psychological morbidity and help people with dementia stay at home longer. Programs that involve the patients and their families and are more intensive and modified to CGs' needs may be more successful. Future research should try to improve clinicians' abilities to prescribe interventions. [source] Contemporary landscape burning patterns in the far North Kimberley region of north-west Australia: human influences and environmental determinantsJOURNAL OF BIOGEOGRAPHY, Issue 8 2004T. Vigilante Abstract Aim, This study of contemporary landscape burning patterns in the North Kimberley aims to determine the relative influences of environmental factors and compare the management regimes occurring on Aboriginal lands, pastoral leases, national park and crown land. Location, The study area is defined at the largest scale by Landsat Scene 108,70 that covers a total land area of 23,134 km2 in the North Kimberley Bioregion of north-west Australia, including the settlement of Kalumburu, coastline between Vansittart Bay in the west and the mouth of the Berkeley River in the east, and stretching approximately 200 km inland. Methods, Two approaches are applied. First, a 10-year fire history (1990,1999) derived from previous study of satellite (Landsat-MSS) remote sensing imagery is analysed for broad regional patterns. And secondly, a 2-year ground-based survey of burning along major access roads leading to an Aboriginal community is used to show fine-scale burning patterns. anova and multiple regression analyses are used to determine the influence of year, season, geology, tenure, distance from road and distance from settlement on fire patterns. Results, Satellite data indicated that an average of 30.8% (±4.4% SEM) of the study area was burnt each year with considerable variability between years. Approximately 56% of the study area was burnt on three or more occasions over the 10-year period. A slightly higher proportion of burning occurred on average in the late dry season (17.2 ± 3.6%), compared with the early dry season (13.6 ± 3.3%). The highest fire frequency occurred on basalt substrates, on pastoral tenures, and at distances 5,25 km from roads. Three-way anova demonstrated that geological substrate and land use were the most significant factors influencing fire history, however a range of smaller interactions were also significant. Analysis of road transects, originating from an Aboriginal settlement, showed that the timing of fire and geology type were the most significant factors affecting the pattern of area burnt. Of the total transect area, 28.3 ± 2.9% was burnt annually with peaks in burning occurring into the dry season months of June, August and September. Basalt uplands (81.2%) and lowlands (30.1%) had greater areas burnt than sandstone (12.3%) and sands (17.7%). Main conclusions, Anthropogenic firing is constrained by two major environmental determinants; climate and substrate. Seasonal peaks in burning activity in both the early and late dry season relate to periods of optimal fire-weather conditions. Substrate factors (geology, soils and physiognomy) influence vegetation-fuel characteristics and the movement of fire in the landscape. Basalt hills overwhelmingly supported the most frequent wildfire regime in the study region because of their undulating topography and relatively fertile soils that support perennial grasslands. Within these spatial and temporal constraints people significantly influenced the frequency and extent of fire in the North Kimberley thus tenure type and associated land uses had a significant influence on fire patterning. Burning activity is high on pastoral lands and along roads and tracks on some tenure types. While the state government uses aerial control burning and legislation to try to restrict burning to the early dry season across all geology types, in practice burning is being conducted across the full duration of the dry season with early dry season burning focused on sandstone and sand substrates and late dry season burning focused on basalt substrates. There is greater seasonal and spatial variation in burning patterns on landscapes managed by Aboriginal people. [source] Mortality patterns in infectious salmon anaemia virus outbreaks in New Brunswick, CanadaJOURNAL OF FISH DISEASES, Issue 11 2005K L Hammell Abstract Mortality levels attributed to infectious salmon anaemia viral (ISAV) infections were examined at the net pen and site level in the 1996 smolt year class in three areas of New Brunswick, Canada. The year class in this region was the first known to have potential exposure to ISAV beginning at the time of seawater transfer. There was considerable variability in mortality patterns among net pen groups of fish. Net pen outbreak definitions were based on at least seven high mortality days in which there were at least 100 per 100 000 fish per day or >5% cumulative mortality for the study period. There were 106 net pen outbreaks in a study population consisting of 218 net pens. Although the number of new cases decreased as water temperature decreased, overall mortality levels at the study sites did not decrease noticeably. The median peak daily mortality rate during outbreaks was 492 per 100 000 fish per day, with 10% of cases experiencing >5200 mortalities per 100 000 fish per day. The median duration of outbreaks in net pens for which the fish were not slaughtered during the outbreak was 33 days and the median total loss in those outbreaks was 6600 per 100 000 fish. [source] Association of cytokine genetic polymorphisms with the humoral immune response to recombinant vaccine against HBV in infantsJOURNAL OF MEDICAL VIROLOGY, Issue 6 2010Luciana Conci Macedo Abstract The prevention of hepatitis B by vaccination is one the most efficient tools to avoid the transmission of the virus, although a considerable variability to the anti-HBsAg antibody response has been described. Recently, polymorphisms of cytokine regulating genes have been described which seem to influence the immune response to various antigens. This article's objective was to evaluate the influence of cytokine genetic polymorphisms onto the humoral immune response to hepatitis B vaccine in infants. Vaccinated children were classified according to the level of anti-HBsAg antibody titles. The genotyping for TNF (,308), TGFB1 (+869, +915), IL-10 (,1082, ,819, ,592), IL-6 (,174), and IFNG (+874) was accomplished by the PCR-SSP technique. The TNF (,308) allele A presented a lower but not statistically significant frequency at 5% level in high responder patients (3.7% vs. 12.3%, P,=,0.0919). The same was seen for the TNF (,308) genotype GA (7.4% vs. 24.5%, P,=,0.0757). Further studies in other populations and evaluation of a greater number of individuals may contribute for a better understanding of the cytokine gene polymorphism influence in general and TNF polymorphism more specifically in the humoral immune response to the HBsAg vaccination in newborn children. J. Med. Virol. 82:929,933, 2010. © 2010 Wiley-Liss, Inc. [source] Effects of Prenatal Alcohol Exposure on Brain Activation During an Arithmetic Task: An fMRI StudyALCOHOLISM, Issue 11 2009Priya Santhanam Background:, While behavioral studies have established that prenatal alcohol exposure (PAE) can result in diminished arithmetic processing capability, the underlying neural correlates of this deficit are still unclear. The aim of the present study was to use functional magnetic resonance imaging to determine the effect of PAE on neuronal activation during a subtraction task. Methods:, Participants were young adults from a low socio-economic status population who were identified prenatally; the sample consisted of healthy unexposed controls (n = 17) and PAE who were subdivided based on the presence (n = 19) or absence of physical dysmorphic signs (n = 18). Multiple regression analysis was used to determine extent of activation and percent signal change during arithmetic processing, using a letter-matching task as the baseline. Region of interest analysis of activation was performed in the native space and normalized for each individual to compensate for the considerable variability in head size observed in the alcohol-exposed population. Results:, An exposure-dependent response was observed in task performance and neuronal activation. Dysmorphic PAE individuals showed significantly lower task-related performance and activation in regions known to be associated with arithmetic processing, including left superior and right inferior parietal regions and medial frontal gyrus, while the nondysmorphic PAE group was generally intermediate but not significantly different from the control group in task performance and activation. Conclusions:, Results indicate that there is a range of effects of PAE on arithmetic processing and that the severity of this deficit may be dependent on degree of impairment demonstrated by the exposed individual. Evidence of physical dysmorphia may be indicative of functional damage to regions associated with arithmetic calculation, resulting in markedly impaired neuronal recruitment. [source] Assessing oral cancer early detection: clarifying dentists' practicesJOURNAL OF PUBLIC HEALTH DENTISTRY, Issue 2 2010Charles W. LeHew PhD Abstract Objective: This study explores new methods for assessing in greater detail what dentists do when they perform oral cancer early detection examinations. It clarifies practice behaviors and opens opportunities to identify factors that facilitate thorough early detection examinations by clinicians and to assess the relative effectiveness of different examination procedures. Methods: A 38-item survey instrument was e-mailed to dentists in a western US, multistate dental practice group. Questionnaires were received by 241 dentists, and 102 responded. An Oral Cancer Knowledge scale (0 to 14) was generated from correct responses on oral cancer general knowledge. An Oral Cancer Examination Thoroughness scale was calculated from the two dimensions of reported usage and frequency of procedures in oral cancer examinations. Results: Nearly all responding dentists were in general practice (90%), with a median year of graduation from dental school of 1994. The Oral Cancer Knowledge scores ranged from 5 to 14 with a mean of 10.4. The mean Thoroughness of Examination score was 11.34 (range 0 to 20). The two scales were not statistically correlated (r = ,0.015, P = 0.883). Statistically, recency of continuing education was significantly associated with knowledge (P = 0.0284) and appears to be marginally associated with thoroughness (P = 0.075). Conclusions: This study documents considerable variability in dentists' knowledge and thoroughness of examinations. The scales provide tools for future studies for improving understanding of early detection of oral cancer in clinical practice. [source] A Review of 21 Curricula for Abstinence-Only-Until-Marriage ProgramsJOURNAL OF SCHOOL HEALTH, Issue 3 2005Kelly L. Wilson ABSTRACT: The authors reviewed the content, methods, and overall quality of 21 curricula used in abstinence-only-until-marriage programs. Only materials designed for use in middle school grades (fifth to eighth) or with middle school-aged audiences (9,13 years of age), which presented the abstinence message in at least 40% of their content, were included. A rating instrument adapted from 2 sets of education guidelines structured the assessment of each curriculum. Four experienced teachers rated each curriculum. Curricula exhibited considerable variability in overall quality ratings. While on average, materials scored a 3.33 on a 1-to-5 scale (1 = Unacceptable; 5 = Excellent), 12 curricula received summative scores above the average, with 4 scoring 4.0 or higher. Eight curricula, however, received a below-average rating. While abstinence materials vary considerably in terms of overall quality, the values and world views underlying this sample of curricula were clear and consistent: those who develop abstinence education curricula value nonsexual antecedents of sexual behavior such as skills (goal setting, decision making, and assertiveness), ideals (fidelity, friendships), and psychological factors such as self-esteem. [source] Differential Effects of Ethanol on Insulin-Like Growth Factor-I Receptor SignalingALCOHOLISM, Issue 2 2000Andrea E.M. Seiler Background: Activation of the insulin-like growth factor I receptor (IGF-IR) by its ligands IGF-I and IGF-II induces cell proliferation and protects against apoptosis. Ethanol inhibits IGF-IR tyrosine autophosphorylation, which subsequently interferes with the activation of key downstream signaling mediators including insulin-receptor substrate-1, phosphatidylinositol 3-kinase, and mitogen-activated protein (MAP) kinase. The ethanol-induced inhibition of IGF-IR signaling reduces mitogenesis and enhances apoptosis. In the current study, we demonstrate that the antiproliferative action of ethanol can be modulated by differential sensitivity of the autophosphorylation of the IGF-IR to ethanol. Methods: A series of subclones was generated from 3T3 cells that express the human IGF-IR. Results: There was considerable variability in the ability of ethanol to inhibit IGF-I-dependent IGF-IR tyrosine autophosphorylation and MAP kinase activation, despite equivalent IGF-IR expression. The IGF-IR was completely resistant to a high concentration of ethanol (150 mM) in several subclones. The sensitivity of IGF-IR autophosphorylation to ethanol correlated directly with the inhibition of IGF-I-mediated MAP kinase activation and cell proliferation. Resistant subclones exhibited features of the transformed phenotype including high MAP kinase activity, partial loss of contact inhibition, and the development of foci at confluency. The IGF-IR isolated from ethanol-resistant cells was similarly resistant to ethanol in autophosphorylation reactions in vitro, whereas ethanol inhibited the autophosphorylation of IGF-IR obtained from sensitive cells. Conclusions: Our findings are the first to demonstrate the modulation of ethanol sensitivity of a tyrosine kinase receptor, and they provide a molecular basis for differential effects of ethanol on cell proliferation. [source] Malaria Antibodies and Mefloquine Levels among United Nations Troops in AngolaJOURNAL OF TRAVEL MEDICINE, Issue 3 2001Eli Schwartz Background: The United Nations deployed about 8,000 soldiers in a peacekeeping mission in Angola. Malaria is the most common disease there and consequently it was the major risk to the UN troops. Most of them are from malaria free areas. As a result of improper prophylactic measures there were many cases of malaria, including some deaths in 1995. In February,March 1996, an Israeli team was sent to Angola to evaluate the malaria situation among UN soldiers. This paper deals specifically with some aspects of chemoprophylaxis and diagnosis. The efforts were concentrated in one particular area where malaria incidence had been reported as the highest. Methods: Blood samples were collected from nonimmune soldiers who were using mefloquine as a prophylactic drug and were exposed to malaria. The mefloquine and the antimalarial antibody plasma levels were monitored. Results: While the local laboratory indicated that about 80% had a malaria episode, the serological results revealed that only 5 soldiers of the 56 (9%) examined had antimalarial antibodies, of which 3 were Angolans. Despite a controlled prophylactic regimen there was considerable variability in mefloquine plasma levels: 46% of the samples were below the required prophylactic level and 26% above it. All patients who were proven positive with malaria by both microscopic and serologic observation had a low level of mefloquine. Conclusions: In field conditions, a kit which identifies plasmodial antigens, is preferable, to a microscopic diagnostic method. Controlled mefloquine prophylaxis may not prevent malaria, especially when blood levels are low. The reason for the low mefloquine blood levels is not clear and needs further evaluation. [source] Airway Mucus in Recurrent Airway Obstruction, Short-Term Response to Environmental ChallengeJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 1 2004V. Gerber Mucus accumulation and neutrophilic inflammation in the airways are hallmarks of heaves. Endoscopically visible mucus accumulations, however, have not been studied during exposure to dusty hay and allergens (ie, environmental challenge). We hypothesized that (1) heaves-affected horses have increased mucus accumulation compared with controls, (2) mucus accumulations increase in heaves-affected horses during environmental challenge, and (3) environmental challenge also induces neutrophilic inflammation and mucus accumulation in control horses. Mucus accumulation was graded endoscopically (mucus grades [MGs] 1,5), and airway inflammation was evaluated by bronchoalveolar lavage fluid (BALF) cytology before (0 hours) and during (6, 24, 48 hours) environmental challenge. Large amounts of mucus (MG 4,5) were specific for heaves-affected horses in this study. Variation among controls was considerable, however, and intermediate grades (MG 2,3) were nonspecific, showing complete overlap between the 2 groups. Median mucus accumulations (25th, 75th percentiles) increased in heaves-affected horses from MG 2.5 (1.5, 3.5) at baseline to MG 3.5 (2.0, 4.0), 4.0 (3.0, 4.0), and 4.0 (4.0, 4.0) at 6, 24, and 48 hours, respectively. MG values did not increase in controls,overall MG 1.0 (1.0, 2.0),even though controls also showed a moderate increase of BALF neutro-phils. Mucus accumulations before and especially after exposure to dust and allergens are increased in heaves-affected horses compared with controls. Healthy controls show considerable variability in mucus accumulation but, despite an influx of neutrophils into the airways, no increase of mucus accumulation after exposure to hay dust. [source] Patterns of muscle involvement in inclusion body myositis: Clinical and magnetic resonance imaging studyMUSCLE AND NERVE, Issue 11 2001Beverley A. Phillips PhD Abstract The differential patterns of muscle involvement in the upper and lower limbs in sporadic inclusion body myositis (sIBM) were examined in 18 patients using both quantitative and manual muscle testing as well as magnetic resonance imaging (MRI) in 9 patients. Weakness of the quadriceps femoris and the forearm flexors was present in most patients, but there was considerable variability in the patterns and severity of muscle involvement. MRI disclosed preferential patterns of muscle involvement within functional groups such as the quadriceps femoris, in which there was severe involvement of the vasti with relative sparing of the rectus femoris, and the triceps surae, in which selective involvement of the medial gastrocnemius was common. Involvement of flexor digitorum profundus on MRI was found in only one third of patients. The results emphasize the variability in the clinical phenotype and differential susceptibility of muscles to the disease process in sIBM. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1526,1534, 2001 [source] Employee experiences with volunteersNONPROFIT MANAGEMENT & LEADERSHIP, Issue 4 2010Assessment, antecedents, description, outcomes Volunteers frequently serve public and nonprofit organizations, among them libraries, parks and recreation departments, social service groups, and religious organizations. Research on volunteers and volunteerism traditionally focuses on antecedents to volunteering and outcomes for volunteers. In this study, we attempt to build on the existing literature by examining the volunteer experience from the paid employee's vantage point. Using a sample of employees who work alongside volunteers in animal care organizations (N = 270), we examine how employees described the volunteers with whom they interact. Although these assessments were generally positive, there was considerable variability. This appears to be explained, in part, by each organization's volunteer resources management practices. Results also indicate that employees who reported less satisfactory experiences with volunteers also reported being more stressed, overworked, and less committed to the organization, and having a greater intention to quit. Importantly, these results held up even after controlling for general job satisfaction. Implications of these findings for theory and practice are discussed. [source] | |||||||||||||||||||||||||||||||||||||