Chinese and European privets are among the most aggressive invasive shrubs in forestlands of the southern United States. We analyzed extensive field data collected by the U.S. Forest Service covering 12 states to iden...
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Chinese and European privets are among the most aggressive invasive shrubs in forestlands of the southern United States. We analyzed extensive field data collected by the U.S. Forest Service covering 12 states to identify potential determinants of invasion and to predict likelihood of further invasion under a variety of possible management strategies. Results of multiplelogisticregression, which classified 75% of the field plots correctly with regard to species presence and absence, indicated probability of invasion is correlated positively with elevation, adjacency (within 300 m) to waterbodies, mean extreme maximum temperature, site productivity, species diversity, natural regeneration, wind disturbance, animal disturbance, and private land ownership and is correlated negatively with slope, stand age, site preparation, artificial regeneration, distance to the nearest road, fire disturbance, and public land ownership. Habitats most at risk to further invasion (likelihood of invasion > 10%) under current conditions occur throughout Mississippi, with a band stretching eastward across south-central Alabama, and in eastern Texas and western Louisiana. Invasion likelihoods could be reduced most by conversion to public land ownership, followed by site preparation, fire disturbance, artificial regeneration, and elimination of animal disturbance. While conversion of land ownership may be neither feasible nor desirable, this result emphasizes the opportunity for reducing the likelihood of invasions on private lands via increased use of selected management practices.
Introduction: Although mammographic density is an established risk factor for breast cancer, its use is limited in clinical practice because of a lack of automated and standardized measurement methods. The aims of thi...
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Introduction: Although mammographic density is an established risk factor for breast cancer, its use is limited in clinical practice because of a lack of automated and standardized measurement methods. The aims of this study were to evaluate a variety of automated texture features in mammograms as risk factors for breast cancer and to compare them with the percentage mammographic density (PMD) by using a case-control study design. Methods: A case-control study including 864 cases and 418 controls was analyzed automatically. Four hundred seventy features were explored as possible risk factors for breast cancer. These included statistical features, moment-based features, spectral-energy features, and form-based features. An elaborate variable selection process using logisticregression analyses was performed to identify those features that were associated with case-control status. In addition, PMD was assessed and included in the regressionmodel. Results: Of the 470 image-analysis features explored, 46 remained in the final logisticregressionmodel. An area under the curve of 0.79, with an odds ratio per standard deviation change of 2.88 (95% CI, 2.28 to 3.65), was obtained with validation data. Adding the PMD did not improve the final model. Conclusions: Using texture features to predict the risk of breast cancer appears feasible. PMD did not show any additional value in this study. With regard to the features assessed, most of the analysis tools appeared to reflect mammographic density, although some features did not correlate with PMD. It remains to be investigated in larger case-control studies whether these features can contribute to increased prediction accuracy.
Background: Postpartum hemorrhage (PPH) is the leading cause of maternal mortality and severe maternal morbidity. The Non-pneumatic Anti-Shock Garment (NASG), a first-aid lower-body compression device, may decrease ad...
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Background: Postpartum hemorrhage (PPH) is the leading cause of maternal mortality and severe maternal morbidity. The Non-pneumatic Anti-Shock Garment (NASG), a first-aid lower-body compression device, may decrease adverse outcomes from obstetric hemorrhage. This article is the first to report the effect of the NASG for PPH. Methods: This pre-intervention/NASG study of 854 women was conducted in four referral facilities in Nigeria and two in Egypt between 2004-2008. Entry criteria were women with PPH due to uterine atony, retained placenta, ruptured uterus, vaginal or cervical lacerations or placenta accreta with estimated blood loss of >= 750 mL and one clinical sign of shock. Differences in demographics, conditions on study entry, treatment and outcomes were examined. The Wilcoxon rank-sum test and relative risks with 95% confidence intervals were calculated for primary outcomes - measured blood loss, emergency hysterectomy, mortality, morbidity (each individually), and a combined variable, "adverse outcomes", defined as severe morbidity and mortality. A multiple logistic regression model was fitted to test the independent association between the NASG and the combined severe morbidity and mortality outcome. Results: Measured blood loss decreased by 50% between phases;women experienced 400 mL of median blood loss after study entry in the pre-intervention and 200 mL in the NASG phase (p < 0.0001). As individual outcomes, mortality decreased from 9% pre-intervention to 3.1% in the NASG phase (RR 0.35, 95% CI 0.19-0.62);severe morbidity decreased from 4.2% to 1%, in the NASG phase (RR 0.24, 95% CI 0.09-0.67). As a combination, "adverse outcomes," decreased from 12.8% to 4.1% in the NASG phase (RR 0.32, 95% CI 0.19-0.53). In a multiple logistic regression model, the NASG was associated with the combined outcome of severe maternal morbidity and mortality (OR 0.42, 95% CI 0.18-0.99). Conclusion: In this non-randomized study, in which bias is inherent, the NASG showed pro
Background: Non-response and drop-out are problems that are commonly encountered in health promotion trials. Understanding the health-related characteristics of non-participants and drop-outs and the reasons for non-p...
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Background: Non-response and drop-out are problems that are commonly encountered in health promotion trials. Understanding the health-related characteristics of non-participants and drop-outs and the reasons for non-participation and drop-out may be beneficial for future intervention trials. Methods: Male construction workers with an elevated risk of cardiovascular disease (CVD) were invited to participate in a lifestyle intervention study. In order to investigate the associations between participation and CVD risk factors, and drop-out and CVD risk factors, crude and multiplelogisticregression analyses were performed. The reasons for non-participation and drop-out were assessed qualitatively. Results: 20% of the workers who were invited decided to participate;8.6% of the participants dropped out before the first follow-up measurement. The main reasons for non-participation were 'no interest', 'current (para-)medical treatment', and 'feeling healthy', and for drop-out they were 'lack of motivation', 'current (para-)medical treatment', and 'disappointment'. Participants were 4.2 years older, had a higher blood pressure, higher total cholesterol, and lower HDL cholesterol than non-participants, and were more likely to report 'tiredness and/or stress' and 'chest pain and/or shortness of breath'. After adjusting for age, most risk factors were not significantly associated with participation. Drop-outs were 4.6 years younger than those who completed the study. The prevalence of smoking was higher among non-participants and drop-outs. Conclusion: Participants had a worse CVD risk profile than non-participants, mainly because of the difference in age. Non-participants and drop-outs were younger and more likely to be smokers. The main reasons for non-participation and drop-out were health-related. Investigators in the field of health promotion should be encouraged to share comparable information.
Background: Endothelial cell dysfunction, by promoting fibrin deposition, has been implicated in the development of multiple organ failure. Altered fibrinolysis during inflammation may participate in microvascular alt...
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Background: Endothelial cell dysfunction, by promoting fibrin deposition, has been implicated in the development of multiple organ failure. Altered fibrinolysis during inflammation may participate in microvascular alterations. We sought to determine whether plasma fibrinolysis was related to the severity of organ dysfunction and/or to the levels of von Willebrand factor (vWF antigen), as a marker of endothelium dysfunction, in critically ill patients. Methods: Forty-nine consecutive patients admitted to an adult medico-surgical intensive care unit (ICU) with (18) or without sepsis (31) were included. C-reactive protein and vWF levels were measured on ICU admission and plasma fibrinolysis was assessed by the Euglobulin Clot Lysis Time (ECLT). The sequential organ failure assessment (SOFA) score and the simplified acute physiology score (SAPS) II were calculated on admission. Results: ECLT was significantly longer in septic than in non-septic patients [1033 min (871-1372) versus 665 min (551-862), p = 0.001]. There were significant correlations between ECLT and C-reactive protein (CRP) concentrations (r = 0.78, p < 0.001) and the Sequential Organ Failure Assessment (SOFA) score (r = 0.39, p = 0.006). The level of vWF was not correlated with the ECLT (r = -0.06, p = 0.65) or the SOFA score (r = -0.02, p = 0.88). Conclusion: ECLT measurement at admission could be a marker of organ dysfunction and a prognostic indicator in critically ill patients.
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