1,804 research outputs found
Bootstrapped CNNs for Building Segmentation on RGB-D Aerial Imagery
Detection of buildings and other objects from aerial images has various
applications in urban planning and map making. Automated building detection
from aerial imagery is a challenging task, as it is prone to varying lighting
conditions, shadows and occlusions. Convolutional Neural Networks (CNNs) are
robust against some of these variations, although they fail to distinguish easy
and difficult examples. We train a detection algorithm from RGB-D images to
obtain a segmented mask by using the CNN architecture DenseNet.First, we
improve the performance of the model by applying a statistical re-sampling
technique called Bootstrapping and demonstrate that more informative examples
are retained. Second, the proposed method outperforms the non-bootstrapped
version by utilizing only one-sixth of the original training data and it
obtains a precision-recall break-even of 95.10% on our aerial imagery dataset.Comment: Published at ISPRS Annals of the Photogrammetry, Remote Sensing and
Spatial Information Science
Societal burden and quality of life in patients with Lisfranc Injuries
Background: The incidence of Lisfranc fractures is rising, along with the incidence of foot fractures in general. These injuries can lead to long-term healthcare use and societal costs. Current economic evaluation studies are scarce in Lisfranc fracture research, and only investigate the healthcare costs. The aim of the present study was to accurately measure the monetary societal burden of disease and quality of life in the first 6 months after the injury in patients with Lisfranc fractures in the Netherlands. Materials and methods: This study used a prevalence-based, bottom-up approach. Patients were included through thirteen medical centres in the Netherlands. Both stable and unstable injuries were included. The societal perspective was used. The costs were measured at baseline, 12 weeks and 6 months using the iMTA MCQ and PCQ questionnaires. Reference prices were used for valuation. Quality-of-life was measured using the EQ-5D-5 L and VAS scores. Results: 214 patients were included. The mean age was 45.9 years, and 24.3% of patients had comorbidities. The baseline questionnaires yielded approximately €2023 as the total societal costs in the 3 months prior to injury. The follow-up questionnaires and surgery costs assessment yielded approximately €17,083 as the total costs in the first 6 months after injury. Of these costs, approximately two thirds could be attributed to productivity losses. The EQ-5D-5 L found a mean index value of 0.449 at baseline and an index value of 0.737 at the 6-month follow-up. Conclusion: The total monetary societal costs in the first 6 months after injury are approximately €17,083. Approximately two thirds of these costs can be attributed to productivity losses. These costs appear to be somewhat higher than those found in other studies. However, these studies only included the healthcare costs. Furthermore, the baseline costs indicate relatively low healthcare usage before the injury compared to the average Dutch patient. The mean QoL index was 0.462 at baseline and 0.737 at 6 months, indicating a rise in QoL after treatment as well as a long-lasting impact on QoL. To our knowledge, this is only the first study investigating the societal costs of Lisfranc injuries, so more research is needed.</p
Psychosocial support interventions to improve treatment outcomes for people living with tuberculosis: a mixed methods systematic review and meta-analysis
BACKGROUND:
People with tuberculosis (TB) face multi-dimensional barriers when accessing and engaging with care. There is evidence that providing psychosocial support within people-centered models of care can improve TB outcomes, however, there is limited consensus on what works. It remains important for such interventions to be rigorously assessed, and mixed methods systematic reviews are one way of synthesising data for policy makers to be able to access such evidence. Mixed methods reviews take a complexity perspective, with qualitative data being used to contextualise the quantitative findings and giving an insight into how interventions are contingent on variations in design and context.
METHODS:
Five electronic databases were searched from January 1 2015 to 14 January 2023 for randomised controlled trials, quasi-experimental trials, cohort studies and qualitative studies of interventions providing psychosocial support (material and/or psychological-based support) to adults with any clinical form of active TB. Studies with inpatient treatment as the standard of care were excluded. Quantitative studies reporting pre-specified standard TB outcomes were eligible. In line with established mixed methods review methodology, a convergent parallel-results synthesis design was followed: quantitative and qualitative syntheses were distinct and carried out using appropriate methods. A convergent coding matrix was then used to integrate the results. The protocol was registered on PROSPERO (CRD42021235211).
FINDINGS:
Twenty-three studies of interventions were included (12 quantitative, 10 qualitative, and 1 mixed methods study). Most studies were conducted in low-and middle-income countries with a high-burden of TB. Three explanatory and contextual middle-range theories from the integration of qualitative and quantitative data were developed: effective interventions provide multi-dimensional support; psychological-based support is transformative but there is insufficient evidence that it improves treatment outcomes on its own; intervention delivery shapes a logic of care.
INTERPRETATION:
This review takes a complexity perspective to provide actionable and timely insight to inform the design and implementation of locally-appropriate and people-centered psychosocial support interventions within national TB programmes.
FUNDING:
There was no funding source for this study
Prophylactic fresh frozen plasma and platelet transfusion have a prothrombotic effect in patients with liver disease
Background and Aims Patients with liver disease acquire complex changes in their hemostatic system, resulting in prolongation of the international normalized ratio and thrombocytopenia. Abnormalities in these tests are commonly corrected with fresh frozen plasma (FFP) or platelet transfusions before invasive procedures. Whether these prophylactic transfusions are beneficial and truly indicated is increasingly debated. In this study, we studied ex vivo effects of FFP and platelet transfusions in patients with liver disease-associated hemostatic changes in a real-life clinical setting. Methods We included 19 patients who were deemed to require prophylactic FFP transfusion by their treating physician and 13 that were prescribed platelet transfusion before a procedure. Hemostatic status was assessed in blood samples taken before and after transfusion and compared with healthy controls (n = 20). Results Ex vivo thrombin generation was preserved in patients with liver disease before FFP transfusion. Following FFP transfusion, both in and ex vivo thrombin generation significantly increased, as evidenced by a 92% and 38% increase in thrombin-antithrombin and prothrombin fragment 1 + 2 levels, respectively, and a 20% increase in endogenous thrombin potential. Platelet counts increased from 28 [21-41] x 10(9)/L before to 43 [39-64] x 10(9)/L after platelet transfusion (P <.01), and was accompanied by increases in in vivo markers of hemostatic activation. Conclusions FFP and platelet transfusion resulted in increased thrombin generation and platelet counts in patients with liver disease, indicating a prothrombotic effect. However, whether all transfusions were truly indicated and had a clinically relevant effect is questionable
Heparins have adequate ex vivo anticoagulant effects in hospitalized patients with cirrhosis
Background Patients with cirrhosis are at risk of venous thromboembolism (VTE), but strategies for thromboprophylaxis have not been defined. Previous in vitro studies suggest an altered anticoagulant effect of heparins in patients with cirrhosis. Objectives To assess the anticoagulant effects of prophylactic low-molecular-weight heparin (LMWH) or unfractionated heparin (UFH) doses in patients with cirrhosis in a real-life clinical setting. Methods We studied patients with cirrhosis (n = 16) and acute-on-chronic liver failure (ACLF) (n = 14), and compared these with patients without underlying liver disease admitted to non-liver general medical wards (n = 18) and non-liver intensive care units (n = 14), respectively. Blood samples were taken before and 4 h after administration of the first dose of LMWH or UFH. We assessed hemostatic status using thrombin generation assays, thrombin-antithrombin complexes (TAT), and conventional coagulation assays, and included healthy controls (n = 20) to establish reference values. Anti-Xa activity was determined to estimate peak heparin levels. Results Baseline thrombin generation was similar among all cohorts and healthy controls despite alterations in conventional coagulation assays. On heparin, both absolute and proportional changes of thrombin generation were comparable between all four cohorts (-62% to -85%). TAT levels decreased in all cohorts apart from the ACLF cohort, but did not correlate with the proportional change in thrombin generation. Anti-Xa activity correlated with the proportional change in thrombin generation in patients receiving LMWH, but not in patients receiving UFH. Conclusions These data suggest that current prophylactic heparin doses have comparable anticoagulant effects in patients with cirrhosis compared with patients without underlying liver disease
Key actors leading knowledge brokerage for sustainable school improvement with PLCs:Who brokers what?
This study investigated knowledge brokerage key actors, in schools that realized sustainable school improvement through professional learning communities (PLCs). To gain insight into what knowledge key actors brokered and how they brokered knowledge, key actors at five secondary schools that worked sustainably with PLCs participated in an in-depth mixed-method study. The findings showed what types of knowledge were brokered and through what activities, what characteristics of key actors were important for knowledge brokerage, and how key actors fit different profiles. These insights can help schools improve their knowledge brokerage as they work towards sustainable school improvement
The validity and precision of the leicester cough questionnaire in COPD patients with chronic cough
Background: A validated instrument to assess the effects of chronic cough on health status in patients with chronic obstructive pulmonary disease (COPD) is currently not available. The Leicester Cough Questionnaire (LCQ) is a cough-specific health status questionnaire which is originally validated for a population of general patients presenting with chronic cough. We examined the psychometric performance of the LCQ in patients with COPD and chronic productive cough. Methods: Concurrent validity, internal consistency, reproducibility and responsiveness were determined. The St. George's Respiratory Questionnaire (SGRQ) and the Short Form-36 (SF-36) were used as external criteria. Questionnaires were completed at the start of the study. After 2 and 12 weeks the LCQ was repeated, together with a global rating of change. Results: In total 54 patients were included. Concurrent validity analysis showed significant correlations between corresponding domains of the LCQ and the SGRQ (r(s) - 0.31 to - 0.60). Corresponding domains of the LCQ and the SF-36 showed weaker correlations (r(s) 0.04 to 0.41). Internal consistency was adequate for two of the three domains (Cronbach's alpha 0.74 - 0.86). Test-retest reliability in stable patients was high (intraclass correlation coefficients 0.79 - 0.93). The mean difference after two weeks was 0.73 (+/- 1.75). Responsiveness analysis indicated that the LCQ was able to detect changes after 12 weeks. Conclusion: The LCQ is a valid, reliable, responsive instrument to measure health status in COPD patients with chronic productive cough
The effect of the DNA flanking the lesion on formation of the UvrB-DNA preincision complex - Mechanism for the UvrA-mediated loading of UvrB onto a DNA damaged site
Bio-organic Synthesi
The Value of Pre-Ablative I-131 Scan for Clinical Management in Patients With Differentiated Thyroid Carcinoma
BACKGROUND: A diagnostic I-131 (Dx) scan is used to detect a thyroid remnant or metastases before treatment of differentiated thyroid cancer (DTC) with I-131. The aim of this study is to specify in which patients with DTC a Dx scan could have an additional value, by studying the effect of the Dx scan on clinical management. METHODS: Patients with DTC, treated with I-131 after thyroidectomy were included in this retrospective cohort study. Twenty-four hours after administration of 37 MBq I-131 a whole body Dx scan and an uptake measurement at the original thyroid bed were performed. Outcomes of the Dx scan and the subsequent changes in clinical management, defined as additional surgery or adjustment of I-131 activity, were reported. Risk factors for a change in clinical management were identified with a binary logistic regression. RESULTS: In 11 (4.2%) patients clinical management was changed, including additional surgery (n=5), lowering I-131 activity (n=5) or both (n=1). Risk factors for a change in clinical management were previous neck surgery (OR 5.9, 95% CI: 1.4-24.5), surgery in a non-tertiary center (OR 13.4, 95% CI: 2.8 – 63.8), TSH <53.4 mU/L (OR 19.64, 95% CI: 4.94-78.13), thyroglobulin ≥50.0 ng/L (OR 7.4, 95% CI: 1.6-34.9) and free T4 ≥4.75 pmol/L (OR 156.8, 95% CI: 128.4-864.2) CONCLUSION: The Dx scan can potentially change clinical management before treatment with I-131, but the yield is low. A Dx-scan should only be considered for patients with a high pre-scan risk of a change in management, based on patient history and prior center-based surgical outcomes
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