Sufficient Data (sufficient + data)

Distribution by Scientific Domains


Selected Abstracts


The response of tree squirrels to fragmentation: a review and synthesis

ANIMAL CONSERVATION, Issue 4 2005
John L. Koprowski
Habitat fragmentation is often considered a major threat to biodiversity; however, our understanding of how fragmentation impacts populations is poor. Identifying appropriate models for such studies is difficult. Tree squirrels are dependent on mature forests for food, cover and nests; these are habitats that are being fragmented rapidly and that are easily defined by humans. Squirrels represent excellent models for study of fragmentation. The literature on tree squirrels was reviewed to glean data on density and home-range size in forest fragments. Sufficient data were available on four species (Sciurus carolinensis, S. niger, S. vulgaris, Tamiasciurus hudsonicus). Density was negatively related to fragment size for S. carolinensis and S. niger and marginally so for T. hudsonicus. Sciurus vulgaris did not exhibit this relationship. Home-range size was analysed for three species of Sciurus and was positively related to forest fragment size for S. carolinensis and S. niger. Again, only S. vulgaris did not to show this relationship. Sciurus vulgaris is rarely found in small forest fragments and is believed to be especially sensitive to fragmentation; other tree squirrels appear to be sensitive to fragmentation in more subtle ways. Home range compaction provides a mechanism by which densities may increase in small fragments. The demographic consequences resultant from the high densities of squirrels found in small woodlots are not known but may explain the forest damage, avian nest predation and reduced diversity often cited to occur in woodland fragments. [source]


Suppression of the postoperative neutrophil leucocytosis following neoadjuvant chemoradiotherapy for rectal cancer and implications for surgical morbidity

COLORECTAL DISEASE, Issue 6 2010
S. F. Kerr
Abstract Objective, The extent to which neoadjuvant chemoradiotherapy for rectal cancer influences postoperative morbidity is controversial. This study investigated whether this treatment suppresses the normal perioperative inflammatory response and explored the clinical implications. Method, Prospective databases were queried to identify 37 consecutive study patients undergoing definitive surgery following 5-FU/capecitabine-based chemoradiotherapy and 34 consecutive untreated control patients operated upon for rectal or rectosigmoid cancer. Preoperative (< 10 days) and postoperative (< 24 h) neutrophil counts, along with morbidity data, were confirmed retrospectively. Univariate and multivariate analyses assessed the apparent effect of chemoradiotherapy on change in neutrophil count. The latter's association with postoperative morbidity was then examined. Results, Sufficient data were available for 34 study and 27 control patients. Repeated-measures ANCOVA revealed significant differences between their perioperative neutrophil counts (P = 0.02). Of the other characteristics which differed between the groups, only age and tumour location were prognostically significant regarding perioperative change in neutrophil count. Accounting for relevant covariates, chemoradiotherapy was significantly associated with a suppressed perioperative neutrophil leucocytosis. Local postoperative complications affected 25 of 61 patients, who had lower perioperative neutrophil increases than their counterparts (P = 0.016). Conclusion, Chemoradiotherapy appears to suppress the perioperative inflammatory response, thereby increasing susceptibility to local postoperative complications. [source]


Sum rules and exact relations for quantal Coulomb systems

CONTRIBUTIONS TO PLASMA PHYSICS, Issue 5-6 2003
V.M. Adamyan
Abstract A complex response function describing a reaction of a multi-particle system to a weak alternating external field is the boundary value of a Nevanlinna class function (i.e. a holomorphic function with non-negative imaginary part in the upper half-plane). Attempts of direct calculations of response functions based on standard approximations of the kinetic theory for real Coulomb condensed systems often result in considerable discrepancies with experiments and computer simulations. At the same time a relatively simple approach using only the exact values of leading asymptotic terms of the response function permits to restrict essentially a subset of Nevanlinna class functions containing this response function, and in this way to obtain sufficient data to explain and predict experimental results. Mathematical details of this approach are demonstrated on an example with the response function being the (external) dynamic electrical conductivity of cold dense hydrogen-like plasmas. In particular, the exact values of the leading terms of asymptotic expansions of the conductivity are calculated. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


A systematic review of structured group interventions with mentally disordered offenders

CRIMINAL BEHAVIOUR AND MENTAL HEALTH, Issue 4 2006
Edward A.S. Duncan
Background,Over the last 15 years, rehabilitation of offenders has been rigorously researched, resulting in new knowledge and understanding about factors decreasing recidivism amongst them. Typically, such interventions have been based on cognitive behavioural therapy. However, until recently, little research had been carried out on the rehabilitation of offenders with mental disorder. The authors present the first systematic review of the efficacy of structured group interventions with mentally disordered offenders. Aim,To evaluate structured group interventions with mentally disordered offenders through systematic review of the evidence for their efficacy and effectiveness. Methods,A standardized search strategy, with complementary methods of data retrieval to ensure a high degree of recall, was employed. Meta-analysis was not undertaken due to sample heterogeneity and lack of comparable data. Instead, effect sizes were calculated on all papers with sufficient data. Pooled effect sizes were calculated for groups of interventions with a similar focus. Results,Twenty studies were retrieved that fitted the inclusion criteria. It was possible to categorize these, predominantly British, studies into four main themes: problem-solving; anger/aggression management; self-harm; and other. The mean pooled effect sizes for the first two groups were suggestive of a moderate to high effect, but methodological variation means that these findings should still be treated as preliminary. Discussion and conclusions,Calculated effect sizes give optimism for the efficacy of structured group interventions with mentally disordered offenders. It is important now that more rigorous and consistent research methods be applied, even in secure hospital environments. Some suggestions towards achieving this are offered, drawing from the work to date, inclusive of the need for agreement on common outcome measures and development of networks to improve sample sizes. Copyright © 2006 John Wiley & Sons, Ltd. [source]


Hierarchical structures of affect and psychopathology and their implications for the classification of emotional disorders,

DEPRESSION AND ANXIETY, Issue 4 2008
David Watson
Abstract The Diagnostic and Statistical Manual of Mental Disorders,IV groups disorders into diagnostic classes on the basis of the subjective criterion of "shared phenomenological features." The current mood and anxiety disorders reflect the logic of older models emphasizing the existence of discrete emotions and, consequently, are based on a fundamental distinction between depressed mood (central to the mood disorders) and anxious mood (a core feature of the anxiety disorders). This distinction, however, ignores subsequent work that has established the existence of a general negative affect dimension that (a) produces strong correlations between anxious and depressed mood and (b) is largely responsible for the substantial comorbidity between the mood and anxiety disorders. More generally, there are now sufficient data to eliminate the current rational system and replace it with an empirically based taxonomy that reflects the actual,not the assumed,similarities among disorders. The existing structural evidence establishes that the mood and anxiety disorders should be collapsed together into an overarching superclass of emotional disorders, which can be decomposed into three subclasses: the distress disorders (major depression, dysthymic disorder, generalized anxiety disorder, posttraumatic stress disorder), the fear disorders (panic disorder, agoraphobia, social phobia, specific phobia), and the bipolar disorders (bipolar I, bipolar II, cyclothymia). An empirically based system of this type will facilitate differential diagnosis and encourage the ultimate development of an etiologically based taxonomy. Depression and Anxiety 25:282,288, 2008. Published 2008 Wiley-Liss, Inc. [source]


Evidence-Based Review of the Use of Cryosurgery in Treatment of Basal Cell Carcinoma

DERMATOLOGIC SURGERY, Issue 6 2003
Agnieszka Kokoszka MD
Background. Cryosurgery has been used to treat basal cell carcinoma (BCC), and it has many technical advantages over other methods. It is therefore important to establish its efficacy as a treatment for BCC. Objective. To review systematically the body of literature reporting on the efficacy of cryosurgery of BCC in terms of recurrence rates and cosmetic results. Methods. A review is given of MEDLINE, EMBASE, CancerLit, and the Cochrane Database of Systematic Reviews for studies that examined cryosurgery in treatment of BCC patients. Results. We found 13 noncontrolled prospective studies and 4 randomized clinical trials comparing cryosurgery to other methods of treatment for BCC. Because of the inability to double blind or placebo control treatment of BCC, none of the studies met criteria for A or B grade evidence, as defined by Sackett. Therefore, all studies were assigned grade C. Conclusions. According to the best evidence, recurrence rates of BCC treated with cryosurgery are low (less than 10%). Except in one study, recurrence rates are calculated based on clinical, rather than histologic diagnosis, which may cause the rates to appear somewhat lower than they actually are, especially with a short follow-up period. Cosmetic results of cryosurgery treatment reported in literature are described as good by most investigators. Overall, there are sufficient data to consider cryosurgery as a reasonable treatment for BCC. There are no good studies, however, comparing cryosurgery with other modalities, particularly with Mohs surgery, excision, or electrodesiccation and curettage so that no conclusion can be made whether cryosurgery is as efficacious as other methods. Also, there is no evidence on whether curetting the lesions before cryosurgery affects the efficacy of treatment. [source]


Mechanisms of change in motivational interviewing: a review and preliminary evaluation of the evidence

ADDICTION, Issue 5 2009
Timothy R. Apodaca
ABSTRACT Aims Motivational interviewing (MI) is an efficacious treatment for substance use disorders. However, little is known about how MI exerts its therapeutic effects. This review is a first attempt to summarize and evaluate the evidence for purported within-session mechanisms of change. The primary question of interest was: which MI constructs and variables appear to be the most promising candidates for mechanisms of change? Methods Literature searches were conducted to identify studies delivering MI in an individual format for the treatment of substance use disorders. Our search identified a total of 152 studies for review; 19 studies met inclusion criteria by providing data on at least one link in the causal chain model under examination. Effect size estimates were calculated for every possible step in the causal model where sufficient data were provided by study authors. Results Four constructs of therapist behavior were evaluated: MI-Spirit, MI-Consistent behaviors, MI-Inconsistent behaviors and therapist use of specific techniques. Five constructs of client behavior were evaluated: change talk/intention, readiness to change, involvement/engagement, resistance and the client's experience of discrepancy. The absence of experimental and full mediation studies of mechanisms of change was notable. Effect sizes were generally mixed. Conclusions The most consistent evidence was found for three constructs: client change talk/intention (related to better outcomes); client experience of discrepancy (related to better outcomes); and therapist MI-Inconsistent behavior (related to worse outcomes). Regarding therapist use of specific techniques, use of a decisional balance exercise showed the strongest association to better outcomes. [source]


Analysis of rain quality data from the South African interior

ENVIRONMETRICS, Issue 4 2002
Jacky Galpin
Abstract Rain acidity may be ascribed to emissions from power station stacks, as well as emissions from other industry, biomass burning, maritime influences, agricultural influences, etc. Rain quality data are available for 30 sites in the South African interior, some from as early as 1985 for up to 14 rainfall seasons, while others only have relatively short records. The article examines trends over time in the raw and volume weighted concentrations of the parameters measured, separately for each of the sites for which sufficient data are available. The main thrust, however, is to examine the inter-relationship structure between the concentrations within each rain event (unweighted data), separately for each site, and to examine whether these inter-relationships have changed over time. The rain events at individual sites can be characterized by approximately eight combinations of rainfall parameters (or rain composition signatures), and these are common to all sites. Some sites will have more events from one signature than another, but there appear to be no signatures unique to a single site. Analysis via factor and cluster analysis, with a correspondence analysis of the results, also aid interpretation of the patterns. This spatio-temporal analysis, performed by pooling all rain event data, irrespective of site or time period, results in nine combinations of rainfall parameters being sufficient to characterize the rain events. The sites and rainfall seasons show patterns in these combinations of parameters, with some combinations appearing more frequently during certain rainfall seasons. In particular, the presence of the combination of low acetate and formate with high magnesium appears to be increasing in the later rainfall seasons, as does this combination together with calcium, sodium, chloride, potassium and fluoride. As expected, sites close together exhibit similar signatures. Copyright © 2002 John Wiley & Sons, Ltd. [source]


Managing non-target, data-poor species using catch limits: lessons from the Alaskan groundfish fishery

FISHERIES MANAGEMENT & ECOLOGY, Issue 4 2010
R. F. REUTER
Abstract, The 2006 reauthorisation of the Magnuson-Stevens Fishery Conservation and Management Act requires annual catch limits for all target and non-target species within federally managed fisheries in the United States. In Alaska, both target and non-target species in the Alaska groundfish fisheries have been managed using catch limits since the early 1990s. Non-target species that are caught incidentally in a fishery require monitoring to ensure that the population is not negatively impacted by commercial fishing. Resource assessment scientists have been challenged with obtaining sufficient data to recommend an acceptable catch level for management of these species. This paper reviews three case studies where a catch limit is determined for non-target species when certain data are limited: (1) varying levels of biomass and catch data for all species within a species group or complex; (2) adequate catch data but no biomass data; (3) emerging target fishery of data-poor species, plus an example of how a complex of ecosystem component species is managed. [source]


Disease-specific Helicobacter pylori Virulence Factors: The Unfulfilled Promise

HELICOBACTER, Issue S1 2000
David Y. Graham
A number of putative virulence factors for Helicobacter pylori have been identified including cagA, vacA and iceA. The criteria for a true virulence factor includes meeting the tests of biologically plausibility with the associations being both experimentally and epidemiologically consistent. Although disease-specific associations have been hypothesized/claimed, there are now sufficient data to conclusively state that none of these putative virulence factors have disease specificity. CagA has been claimed to be associated with increased mucosal IL-8 and inflammation, increased density of H. pylori in the antrum, duodenal ulcer (DU), gastric cancer, and protection against Barrett's cancer. Only the increase in IL-8/inflammation is direct and substantiated. Different H. pylori strains with functional cag pathogenicity islands do not vary in virulance as it has been shown that mucosal IL-8 levels are proportional to the number of cagA +H. pylori independent of the disease from which the H. pylori were obtained. It is now known that the density of either cagA + and cagA,H. pylori in the antrum of patients with H. pylori gastritis is the same. In contrast, the mean density of H. pylori in the antrum in DU is greater than in the antrum of patients with H. pylori gastritis. Of interest, the density of H. pylori is higher in the corpus of patients with H. pylori gastritis than those with DU, suggesting that acid secretion plays a critical role in these phenomena. The presence of a functional cag pathogenicity island increases inflammation and it is likely that any factor that results in an increase in inflammation also increases the risk of a symptomatic outcome. Nevertheless, the presence of a functional cag pathogenicity island has no predictive value for the presence, or the future development of a clinically significant outcome. The hypothesis that iceA has disease specificity has not been confirmed and there is currently no known biological or epidemiological evidence for a role for iceA as a virulence factor in H. pylori -related disease. The claim that vacA genotyping might prove clinically useful, e.g. to predict presentation such as duodenal ulcer, has been proven wrong. Analysis of the worldwide data show that vacA genotype s1 is actually a surrogate for the cag pathogenicity island. There is now evidence to suggest that virulence is a host-dependent factor. The pattern of gastritis has withstood the test of time for its relation to different H. pylori -related diseases (e.g. antral predominant gastritis with duodenal ulcer disease). The primary factors responsible for the different patterns of gastritis in response to an H. pylori infection are environmental (e.g. diet), with the H. pylori strain playing a lesser role. Future studies should work to eliminate potential bias before claiming disease associations. Controls must exclude regional or geographic associations related to the common strain circulation and not to the outcome. The authors must also control for both the presence of the factor and for the disease association. The study should be sufficiently large and employ different diseases and ethnic groups for the results to be robust. The findings in the initial sample (data derived hypothesis) should be tested in a new group (hypothesis testing), preferably from another area, before making claims. Finally, it is important to ask whether the results are actually a surrogate for another marker (e.g. vacA s1 for cagA) masquerading for a new finding. Only the cag pathogenicity island has passed the tests of biological plausibility (increased inflammation) and experimental and epidemiological consistency. [source]


Ulcerative colitis and clinical course: Results of a 5-year population-based follow-up study (the IBSEN study)

INFLAMMATORY BOWEL DISEASES, Issue 7 2006
Magne Henriksen MD
Abstract Background: The majority of studies concerning the clinical course and prognosis in ulcerative colitis (UC) are old, retrospective in design, or hospital based. We aimed to identify clinical course and prognosis in a prospective, population-based follow-up study Materials and Methods: Patients diagnosed with inflammatory bowel disease (IBD) or possible IBD in southeastern Norway during the period 1990,1994 were followed prospectively for 5 years. The evaluation at 5 years included an interview, clinical examination, laboratory tests, and colonoscopy. Results: Of 843 patients diagnosed with IBD, 454 patients who had definite UC and for whom there were sufficient data for analysis were alive 5 years after inclusion in the study. The frequency of colectomy in this population was 7.5%. Forty-one percent of the patients were not taking any kind of medication for IBD at 5 years. Of the patients initially diagnosed with proctitis, 28% had progressed during the observation period, 10% to extensive colitis. The majority of the patients (57%) had no intestinal symptoms at 5 years, and only a minority (7%) had symptoms that interfered with everyday activities. Among the patients who underwent colonoscopy at the 5-year visit, symptoms were frequently reported in patients without macroscopic inflammation (44%). A relapse-free course was observed in 22% of the patients. A decrease in symptoms during the follow-up period was the most frequent course taken by the disease and was observed in 59% of the cases. The extent of disease was unrelated to symptoms at 5 years and also to relapse rate and course of disease during the 5-year period. Conclusions: The disease course and prognosis of UC appears better than previously described in the literature. The frequency of surgery was low, and only a minority of the patients had symptoms that interfered with their everyday activities 5 years after diagnosis. [source]


Segmental testicular ischaemia: presentation, management and follow-up

INTERNATIONAL JOURNAL OF ANDROLOGY, Issue 5 2009
D. Gianfrilli
Summary Segmental infarction of the testis is a rare event. Less than 40 cases have been reported in the literature and its aetiology remains largely unknown. The diagnosis is challenging and its identification crucial as partial ischaemia is frequently confused with testicular tumours and unnecessarily treated with orchiectomy. The objectives of this study are to: (i) raise awareness of this rare condition, (ii) provide the distinctive clinical and radiological features enabling pre-operative diagnosis, (iii) promote appropriate screening of causative factors and (iv) propose an alternative management approach to avoid surgery and preserve fertility. We describe three cases of partial testicular ischaemia in men presenting with reduced sperm quality. The cases demonstrate the ultrasound and magnetic resonance imaging appearance of testicular ischaemia. The surveillance strategy adopted for these lesions indicates that over 2 years of follow-up, marginal changes in the lesions can occur. Histology revealed that infiltration by stromal cells, leucocytes and macrophages is responsible for the remodelling of these lesions. Screening of risk factors for thromboembolism revealed that all patients carried a methylenetetrahydrofolate reductase 677C,T (MTHFR) mutation in a gene involved in folate metabolism, and either borderline or elevated homocysteine levels. Distinctive features permit the pre-operative diagnosis of segmental testicular ischaemia. There are sufficient data to assert that a surveillance strategy is safe and feasible. We speculate that the defects in folate metabolism may pre-dispose individuals to the development of testicular infarction and infertility. [source]


The role of males in the dynamics of ungulate populations

JOURNAL OF ANIMAL ECOLOGY, Issue 6 2002
Atle Mysterud
Summary 1In this review, we focus on how males can affect the population dynamics of ungulates (i) by being a component of population density (and thereby affecting interpretation of log-linear models), and (ii) by considering the mechanisms by which males can actively affect the demographic rates of females. 2We argue that the choice of measure of density is important, and that the inclusion or exclusion of males into models can influence results. For example, we demonstrate that if the dynamics of a population can be described with a first-order auto-regressive process in a log-linear framework, the asymmetry between the effects of females on the male dynamics and vice versa can introduce a second order process, much in the same way that the interaction between disease and host or predator and prey can. It would be useful for researchers with sufficient data to explore the affects of using different density measures. 3In general, even in harvested populations with highly skewed sex ratios, males are usually able to fertilize all females, though detailed studies document a lower proportion of younger females breeding when sex ratios are heavily female biased. It is well documented that the presence of males can induce oestrus in females, and that male age may also be a factor. In populations with both a skewed sex ratio and a young male age structure, calving is delayed and less synchronous. We identify several mechanisms that may be responsible for this. 4Delayed calving may lower summer survival and autumn masses, which may lead to higher winter mortality. If females are born light, they may require another year of growth before they start reproducing. Delayed calving can reduce future fertility of the mother. As the proportion of calves predated during the first few weeks of life is often very high, calving synchrony may also be an important strategy to lower predation rates. 5We argue that the effects of males on population dynamics of ungulates are likely to be non-trivial, and that their potential effects should not be ignored. The mechanisms we discuss may be important , though much more research is required before we can demonstrate they are. [source]


Risk markers associated with challenging behaviours in people with intellectual disabilities: a meta-analytic study

JOURNAL OF INTELLECTUAL DISABILITY RESEARCH, Issue 6 2003
K. McClintock
A meta-analysis of prevalence and cohort studies conducted over the last 30 years was carried out to identify risk markers for challenging behaviour shown by individuals with intellectual disabilities (IDs). A total of 86 potential studies was identified from the review, with 22 (25.6%) containing sufficient data to enable a statistical analysis to be conducted. Results indicated that males were significantly more likely to show aggression than females, and that individuals with a severe/profound degree of ID were significantly more likely to show self-injury and stereotypy than individuals with a mild/moderate degree of ID. Individuals with a diagnosis of autism were significantly more likely to show self-injury, aggression and disruption to the environment whilst individuals with deficits in receptive and expressive communication were significantly more likely to show self-injury. In most cases, tests for heterogeneity were statistically significant, as expected. The meta-analysis highlighted the paucity of methodologically robust studies of risk markers for challenging behaviours and the lack of data on incidence, prevalence and chronicity of challenging behaviour in this population. [source]


BBN based approach for improving the software development process of an SME,a case study

JOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 2 2010
S. Bibi
Abstract This article proposes an approach for improving the software process of a small/medium company. The methodology is presented through a case study during which estimation models have been applied, evaluated and introduced in a telecommunication software development process. The proposed methodology uses Bayesian Belief Networks to represent the relationships among implementation, product and process metrics and their impact on the development effort. The estimation models that were derived were applied and evaluated on the on-going projects of the company. Finally, by performing the same analysis on data from the International Software Benchmarking Standards Group (ISBSG) repository, it is demonstrated how one company can utilize data from other companies when it lacks sufficient data of its own. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Effects of grazing on geophytes in Mediterranean vegetation

JOURNAL OF VEGETATION SCIENCE, Issue 6 2001
Imanuel Noy-Meir
Zohary & Feinbrun-Dothan (1966,1986) Abstract. The response of geophyte species diversity and frequency of individual geophyte species to cattle grazing was measured at 68 site pairs along fences separating ungrazed from grazed grassland and woodland on different geological formations in northern Israel. Over all site pairs, geophyte species density per 4 m2 was significantly greater in grazed (2.37) than in protected (1.96) sites of the same site pair. There was considerable variation between site pairs in the magnitude and in the direction of the grazing effect. Part of this variation could be explained by differences in site altitude and in geological formation. The positive effect of grazing on geophyte diversity was lower in sites with low productivity. Of 22 geophyte taxa for which sufficient data were available, nine indicated greater frequency in grazed sites compared to only two in ungrazed sites. In 11 other taxa the response was not consistent. A positive response to grazing was most common in geophytes with narrow leaves of the Iridaceae, Liliaceae and allied families. Conservation of the entire geophyte flora in Mediterranean vegetation requires livestock grazing at moderate to high intensities in parts of the area of each community, and light or no grazing in other parts. [source]


NORTH ATLANTIC RIGHT WHALE DISTRIBUTION IN RELATION TO SEA-SURFACE TEMPERATURE IN THE SOUTHEASTERN UNITED STATES CALVING GROUNDS

MARINE MAMMAL SCIENCE, Issue 2 2006
Chérie A. Keller
Abstract Standardized aerial surveys were used to document the winter (December,March) distribution of North Atlantic right whales in their calving area off the coasts of Georgia and northeastern Florida (1991,1998). Survey data were collected within four survey zones in and adjacent to federally designated critical habitat. These data, including whale-sighting locations and sampling effort, were used to describe right whale distribution in relation to sea-surface temperature (SST) from satellite-derived images. Locations where whales were sighted (n= 609) had an overall mean SST of 14.3°C ± 2.1° (range 8°,22°C). Data from two survey zones having sufficient data (including the "early warning system" (EWS) zone and the Florida nearshore) were pooled by season and stratified by month to investigate changes in monthly ambient SST and fine-scale distribution patterns of right whales in relation to SST within spatially explicit search areas. Using Monte Carlo techniques, SSTs and latitudes (means and standard deviations) of locations where whales were sighted were compared to a sampling distribution of each variable derived from daily-search areas. Overall, results support a nonrandom distribution of right whales in relation to SST: during resident months (January and February), whales exhibited low variability in observed SST and a suggested southward shift in whale distribution toward warmer SSTs in the EWS zone; while in the relatively warmer and southernmost survey zone (Florida nearshore), right whales were concentrated in the northern, cooler portion. Our results support that warm Gulf Stream waters, generally found south and east of delineated critical habitat, represent a thermal limit for right whales and play an important role in their distribution within the calving grounds. These results affirm the inclusion of SST in a multivariate predictive model for right whale distribution in their southeastern habitat. [source]


The pathophysiology of tremor

MUSCLE AND NERVE, Issue 6 2001
Günther Deuschl MD
Abstract Tremor is defined as rhythmic oscillatory activity of body parts. Four physiological basic mechanisms for such oscillatory activity have been described: mechanical oscillations; oscillations based on reflexes; oscillations due to central neuronal pacemakers; and oscillations because of disturbed feedforward or feedback loops. New methodological approaches with animal models, positron emission tomography, and mathematical analysis of electromyographic and electroencephalographic signals have provided new insights into the mechanisms underlying specific forms of tremor. Physiological tremor is due to mechanical and central components. Psychogenic tremor is considered to depend on a clonus mechanism and is thus believed to be mediated by reflex mechanisms. Symptomatic palatal tremor is most likely due to rhythmic activity of the inferior olive, and there is much evidence that essential tremor is also generated within the olivocerebellar circuits. Orthostatic tremor is likely to originate in hitherto unidentified brainstem nuclei. Rest tremor of Parkinson's disease is probably generated in the basal ganglia loop, and dystonic tremor may also originate within the basal ganglia. Cerebellar tremor is at least in part caused by a disturbance of the cerebellar feedforward control of voluntary movements, and Holmes' tremor is due to the combination of the mechanisms producing parkinsonian and cerebellar tremor. Neuropathic tremor is believed to be caused by abnormally functioning reflex pathways and a wide variety of causes underlies toxic and drug-induced tremors. The understanding of the pathophysiology of tremor has made significant progress but many hypotheses are not yet based on sufficient data. Modern neurology needs to develop and test such hypotheses, because this is the only way to develop rational medical and surgical therapies. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 716,735, 2001 [source]


AN ADAPTIVE LEARNING FRAMEWORK FOR FORECASTING SEASONAL WATER ALLOCATIONS IN IRRIGATED CATCHMENTS

NATURAL RESOURCE MODELING, Issue 3 2010
SHAHBAZ KHAN
Abstract This paper describes an adaptive learning framework for forecasting end-season water allocations using climate forecasts, historic allocation data, and results of other detailed hydrological models. The adaptive learning framework is based on artificial neural network (ANN) method, which can be trained using past data to predict future water allocations. Using this technique, it was possible to develop forecast models for end-irrigation-season water allocations from allocation data available from 1891 to 2005 based on the allocation level at the start of the irrigation season. The model forecasting skill was further improved by the incorporation of a set of correlating clusters of sea surface temperature (SST) and the Southern oscillation index (SOI) data. A key feature of the model is to include a risk factor for the end-season water allocations based on the start of the season water allocation. The interactive ANN model works in a risk-management context by providing probability of availability of water for allocation for the prediction month using historic data and/or with the incorporation of SST/SOI information from the previous months. All four developed ANN models (historic data only, SST incorporated, SOI incorporated, SST-SOI incorporated) demonstrated ANN capability of forecasting end-of-season water allocation provided sufficient data on historic allocation are available. SOI incorporated ANN model was the most promising forecasting tool that showed good performance during the field testing of the model. [source]


Evaluating measurement error in estimates of worker exposure assessed in parallel by personal and biological monitoring

AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 2 2007
Elaine Symanski PhD
Abstract Background While studies indicate that the attenuating effects of imperfectly measured exposure can be substantial, they have not had the requisite data to compare methods of assessing exposure for the same individuals monitored over common time periods. Methods We examined measurement error in multiple exposure measures collected in parallel on 32 groups of workers. Random-effects models were applied under both compound symmetric and exponential correlation structures. Estimates of the within- and between-worker variances were used to contrast the attenuation bias in an exposure-response relationship that would be expected using an individual-based exposure assessment for different exposure measures on the basis of the intra-class correlation coefficient (ICC). Results ICC estimates ranged widely, indicative of a great deal of measurement error in some exposure measures while others contained very little. There was generally less attenuation in the biomarker data as compared to measurements obtained by personal sampling and, among biomarkers, for those with longer half-lives. The interval ICC estimates were oftentimes wide, suggesting a fair amount of imprecision in the point estimates. Ignoring serial correlation tended to over estimate the ICC values. Conclusions Although personal sampling results were typically characterized by more intra-individual variability than inter-individual variability when compared to biological measurements, both types of data provided examples of exposure measures fraught with error. Our results also indicated substantial imprecision in the estimates of exposure measurement error, suggesting that greater emphasis needs to be given to studies that collect sufficient data to better characterize the attenuating effects of an error-prone exposure measure. Am. J. Ind. Med. 50:112,121, 2007. © 2006 Wiley-Liss, Inc. [source]


Characterizing a Brownfields recreational reuse scenario using the Triad Approach,Assunpink Creek Greenways project

REMEDIATION, Issue 4 2003
James Mack
Since the early 1990s the U.S. government has been developing and implementing public policies that advance the redevelopment of brownfields, and the recent passage of the Small Business Liability Relief and Brownfields Revitalization Act (SBLRBRA) will significantly advance efforts to integrate environmental contamination mitigation and redevelopment. Experience has demonstrated that successful redevelopment requires the collection, analysis, and interpretation of environmental data in a timely and cost-effective manner in order to allow developers and lenders to efficiently use cleanup resources, develop response strategies that integrate cleanup with redevelopment, and support meaningful outreach to involved stakeholders. Recent advances in the science and technology of site characterization hold the promise of improved site characterization outcomes while saving time and money. One such advancement, the Triad Approach, combines systematic up-front planning with the use of a dynamic field investigation process and the generation of real time data to allow in-field decision making on sample location selection. This article describes an application of the Triad Approach to redevelopment of an urban greenway in Trenton, New Jersey. The Triad Approach, initiated through a partnership between the City of Trenton, New Jersey Department of Environmental Protection, New Jersey Institute of Technology, and the U.S. Environmental Protection Agency, demonstrated that this approach could accelerate the characterization of the 60-acre, 11-parcel project area. Environmental issues that were solved using the Triad Approach included the delineation of the extent of historic fill, determination of no further action for several areas of concern, detailed investigation of specific impacted areas and the acquisition of sufficient data to allow the city to make important decisions regarding remediation costs and property acquisition. © 2003 Wiley Periodicals, Inc. [source]


Inflation Targeting as a Framework for Monetary Policy: A Cross-Country Analysis

THE AUSTRALIAN ECONOMIC REVIEW, Issue 3 2003
William Seyfried
This study makes use of a dynamic Taylor-type model to examine the conduct of monetary policy by central banks that profess to engage in inflation targeting. Previous research regarding inflation targeting and Taylor-type rules is reviewed and a dynamic Taylor-type model is developed. Tests for regime shifts upon the adoption of inflation targeting indicate a significant change in policy in each of the nations in the study for which sufficient data were available. Next, the central bank reaction functions were estimated. Results suggest that most of the central banks conducted a policy of inflation targeting by seeking to contain inflationary pressures rather than reacting to current inflation. [source]


Conference Attendance Does Not Correlate With Emergency Medicine Residency In-Training Examination Scores

ACADEMIC EMERGENCY MEDICINE, Issue 2009
H. Gene Hern Jr MD
Abstract Objectives:, The residency review committee for emergency medicine (EM) requires residents to have greater than 70% attendance of educational conferences during residency training, but it is unknown whether attendance improves clinical competence or scores on the American Board of Emergency Medicine (ABEM) in-training examination (ITE). This study examined the relationship between conference attendance and ITE scores. The hypothesis was that greater attendance would correlate to a higher examination score. Methods:, This was a multi-center retrospective cohort study using conference attendance data and examination results from residents in four large county EM residency training programs. Longitudinal multi-level models, adjusting for training site, U.S. Medical Licensing Examination (USMLE) Step 1 score, and sex were used to explore the relationship between conference attendance and in-training examination scores according to year of training. Each year of training was studied, as well as the overall effect of mean attendance as it related to examination score. Results:, Four training sites reported data on 405 residents during 2002 to 2008; 386 residents had sufficient data to analyze. In the multi-level longitudinal models, attendance at conference was not a significant predictor of in-training percentile score (coefficient = 0.005, 95% confidence interval [CI] = ,0.053 to 0.063, p = 0.87). Score on the USMLE Step 1 examination was a strong predictor of ITE score (coefficient = 0.186, 95% CI = 0.155 to 0.217; p < 0.001), as was female sex (coefficient = 2.117, 95% CI = 0.987 to 3.25; p < 0.001). Conclusions:, Greater conference attendance does not correlate with performance on an individual's ITE scores. Conference attendance may represent an important part of EM residency training but perhaps not of ITE performance. [source]


Curcumin in Cancer Chemoprevention: Molecular Targets, Pharmacokinetics, Bioavailability, and Clinical Trials

ARCHIV DER PHARMAZIE, Issue 9 2010
Adeeb Shehzad
Abstract Curcumin (diferuloylmethane), a derivative of turmeric is one of the most commonly used and highly researched phytochemicals. Abundant sources provide interesting insights into the multiple mechanisms by which curcumin may mediate chemotherapy and chemopreventive effects on cancer. The pleiotropic role of this dietary compound includes the inhibition of several cell signaling pathways at multiple levels, such as transcription factors (NF-,B and AP-1), enzymes (COX-2, MMPs), cell cycle arrest (cyclin D1), proliferation (EGFR and Akt), survival pathways (,-catenin and adhesion molecules), and TNF. Curcumin up-regulates caspase family proteins and down-regulates anti-apoptotic genes (Bcl-2 and Bcl-XL). In addition, cDNA microarrays analysis adds a new dimension for molecular responses of cancer cells to curcumin at the genomic level. Although, curcumin's poor absorption and low systemic bioavailability limits the access of adequate concentrations for pharmacological effects in certain tissues, active levels in the gastrointestinal tract have been found in animal and human pharmacokinetic studies. Currently, sufficient data has been shown to advocate phase II and phase III clinical trials of curcumin for a variety of cancer conditions including multiple myeloma, pancreatic, and colon cancer. [source]


Preferences for aspects of a dermatology consultation

BRITISH JOURNAL OF DERMATOLOGY, Issue 2 2006
J. Coast
Summary Background, General practitioners with special interests (GPSIs) are increasingly being used to provide dermatology services in the U.K. Little is known about U.K. dermatology patient attitudes to proposed variations in secondary care service delivery or the values they attach to aspects of the care they receive. Objectives, To quantify preferences for different attributes of care within dermatology secondary care services. Methods, Attributes of care that are important to dermatology patients were derived using in-depth qualitative interviews with 19 patients at different points in the care pathway. A discrete choice experiment using ,best,worst scaling' was sent by post to 119 patients referred to secondary care dermatology services and suitable for GPSI care who had agreed to participate in research. Results, Four attributes were derived from the qualitative work: waiting, expertise, thorough care and convenience. For the discrete choice experiment, 99 patients returned questionnaires, 93 of which contained sufficient data for analysis. All attributes were found to be quantitatively important. The attribute of greatest importance was expertise of the doctor, while waiting time was of least importance. Respondents were willing to wait longer than the current 3 months maximum to receive care that was thorough, 2·1 months to see a team led by an expert and 1·3 months to attend a consultation that is easy to get to. Conclusions, Although the need to reduce outpatient waiting times is a key policy driver behind the expansion of GPSI services, this does not appear to be the most important issue for patients. The thoroughness with which the consultation is provided and the expertise of the clinician seen are higher priorities. [source]


Side-effects of allergen-specific immunotherapy.

CLINICAL & EXPERIMENTAL ALLERGY, Issue 3 2006
A prospective multi-centre study
Summary Background and objective The safety of allergen-specific immunotherapy (SIT) is a parameter of great interest in the overall assessment of the treatment. A clinical database was developed in order to obtain early warnings of changes in the frequency and severity of side-effects and sufficient data for the evaluation of possible risk factors. Methods During a 3-year period, four allergy centres in Copenhagen, Denmark, included data from all patients initiating SIT to a common database. Information on initial allergic symptoms, allergens used for treatment, treatment regimens and systemic side-effects (SSEs) during the build-up phase was collected. Results A total of 1038 patients received treatment with 1709 allergens (timothy, birch, mugwort, house dust mite (HDM), cat, and wasp and bee venom), 23 047 injections in total. Most SIT patients completed the updosing phase without side-effects, but there was a significant difference between allergens: wasp (89%), birch (82%), HDM (81%), cat (74%) and grass (70%) (P=0.004). A total of 582 SSEs were registered in 341 patients. Most side-effects were mild grade 2 reactions (78%). A difference in severity between allergens was observed (P=0.02), with grass giving most problems. The type of allergen but not patient- or centre-related parameters seemed predictive of side-effects. Conclusions Allergen extracts differ in their tendency to produce side-effects. Multi-centre studies like the present one allow more patients to be evaluated, and thereby provide a more efficient surveillance of side-effects. Online Internet-based registration to a central national database of every allergen injection would be an even more powerful tool for evaluation of risk factors and surveillance of side-effects. [source]


Endophthalmitis in the western Sydney region: a case-control study

CLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 6 2001
Somsak Lertsumitkul FRACO
ABSTRACT Background: A retrospective case-control study was conducted to investigate risk factors for endophthalmitis following routine intraocular surgery. Methods: A review was performed of consecutive cases of endophthalmitis from three teaching hospitals in the western Sydney region and matched controls from the same institutions between 1996 and 1998. Results: There were 31 cases and 66 controls. Eighty procedures were phacoemulsification, 15 conventional extracapsular cataract extraction, and two were penetrating keratoplasties. Of the 80 patients who had phacoemulsification surgery, 50 had a clear corneal incision, and 26 had a scleral incision (four were unknown). Logistic regression showed an increased risk of endophthalmitis with surgical complications (P = 0.002) and clear cornea temporal incisions (P = 0.007). Risk of endophthalmitis was reduced with use of subconjunctival injections (P = 0.008). The yield for the Gram stain was 47% and for culture was 67%. Anterior chamber tap in addition to vitreous biopsy alone did not increase the yield for microorganism (P = 0.78). Mean visual acuity on presentation was hand movement with 13 patients (50%) showing visual improvement following intravitreal injections of antibiotics (P = 0.003). Visual prognosis did not correlate with presenting visual acuity but appeared to be better in those who grew Staphylococcus epidermidis or were culture negative. Conclusions: Although this study is unable to draw definite conclusions regarding risk of endophthalmitis in clear corneal temporal cataract surgery, sufficient data suggest the importance of incision type and location. Surgical complication is an important risk factor for endophthalmitis. Use of subconjunctival antibiotic injections at the conclusion of the procedure is recommended. [source]