River ecosystem conceptual models and non‐perennial rivers: A critical review

Conceptual models underpin river ecosystem research. However, current models focus on continuously flowing rivers and few explicitly address characteristics such as flow cessation and drying. The applicability of existing conceptual models to nonperennial rivers that cease to flow (intermittent rivers and ephemeral streams, IRES) has not been evaluated. We reviewed 18 models, finding that they collectively describe main drivers of biogeochemical and ecological patterns and processes longitudinally (upstream-downstream), laterally (channel-riparian-floodplain), vertically (surface water-groundwater), and temporally across local and landscape scales. However, perennial rivers are longitudinally continuous while IRES are longitudinally discontinuous. Whereas perennial rivers have bidirectional lateral connections between aquatic and terrestrial ecosystems, in IRES, this connection is unidirectional for much of the time, from terrestrial-to-aquatic only. Vertical connectivity between surface and subsurface water occurs bidirectionally and is temporally consistent in perennial rivers. However, in IRES, this exchange is temporally variable, and can become unidirectional during drying or rewetting phases. Finally, drying adds another dimension of flow variation to be considered across temporal and spatial scales in IRES, much as flooding is considered as a temporally and spatially dynamic process in perennial rivers. Here, we focus on ways in which existing models could be modified to accommodate drying as a fundamental process that can alter these patterns and processes across spatial and temporal dimensions in streams. This perspective is needed to support river science and management in our era of rapid global change, including increasing duration, frequency, and occurrence of drying.info:eu-repo/semantics/publishedVersio

Which health professionals are most at risk for cardiovascular disease? Or do not be a manager

Objectives: Health care workers constitute a high-risk occupational category owing to the character of their work that includes high-risk environment, shift work and mental as well as physical stress. In occupational medicine, caring for their health condition should be a priority and include measures aimed at preventing cardiovascular diseases. The study aimed at determining the prevalence of cardiovascular disease (CVD) risk factors in employees of a large hospital and assessing their effect on the incidence of cardiovascular events. Materials and Methods: The group comprised 3124 employees with a mean age of 36.1 years (SD = 11.4), out of whom 562 were males (mean age of 37.1 years, range: 18-72; SD = 12.26) and 2562 were females (mean age of 35.9 years, range: 18-68; SD = 11.24). At their initial examination, the employees filled in a questionnaire on basic CVD risk factors (according to valid recommendations). This was supplemented with objective data to determine the risk of CVD using valid charts. From this group, a subset of persons at a high or intermediate risk was selected, comprising 247 individuals with a mean age of 54.1 years (SD = 5.73). After 5-9 years (mean 7.24±1.38 years), they either underwent another examination or their health status was ascertained by phone or in a computer database. The end point was the incidence of cardiovascular events (sudden death, acute myocardial infarction, unstable angina pectoris, percutaneous coronary intervention, cardiac failure, stroke or transient ischemic attack). Results: The end point was noted in a total of 15 males (6.07%) and 6 females (2.42%), being statistically significantly present in managers (males p < 0.00007, females p < 0.00001), male physicians/surgeons (p < 0.025), tertiary-educated males (p < 0.0095), female smokers (p < 0.015), male ex-smokers (p < 0.007), overweight or obese males (p < 0.02) and those with the waist-to-hip ratio above 1.0 (p < 0.005). Conclusions: Cardiovascular events are most likely to occur in obese male physicians/surgeons holding managerial positions and in female managers

Rethinking ecosystem service indicators for their application to intermittent rivers

In these times of strong pressure on aquatic ecosystems and water resources due to climate change and water abstraction, intermittent rivers and ephemeral streams (IRES) (rivers that periodically cease to flow and/or dry) have become valuable assets. Indeed, not only do they supply water but they also offer services for humanity. Despite a growing recognition towards IRES, information for assessing their ecosystem services (ES) remains scarce. In a first step, an international interdisciplinary group of researchers developed a methodological framework to acknowledge ES provided by IRES using 109 indicators. A subset of selected ES indicators was then applied to two case studies: the Rio Seco in the Algarve (Portugal) and the Giofyros River in Crete (Greece). This paper discusses the applicability of these indicators, including the temporal and spatial variability of IRES flow regimes. Aspects of the framework, such as the methods and time required for data collection, the nature (de-mand or supply) and functionality of each indicator are discussed. The new framework accounts for flow intermittence in ES analyses and can help scientists and water managers to i) increase the ease and justification for IRES use in management approaches and ii) improve their conservation and restoration with a comprehensive set of appropriate indicators for IRES. In addition, the comprehensive nature of the proposed indicators ensures that they can be understood by a broad audience and easily applicable. Since they were designed through a public participation process, the setting has been prepared for holistic stakeholder analysis and education around IRES functions and associated ES. From a management point of view, it would be particularly relevant to perform an economic evaluation with this new framework to understand the value of each ES category and their tradeoffs. For the scientific community, however, it is important to consider public preferences to design socially accepted policies. The proposed indicators can successfully bridge these elements, hereby establishing a solid basis for the assessment of ES provided by IRES

Rethinking ecosystem service indicators for their application to intermittent rivers

In these times of strong pressure on aquatic ecosystems and water resources due to climate change and water abstraction, intermittent rivers and ephemeral streams (IRES) (rivers that periodically cease to flow and/or dry) have become valuable assets. Indeed, not only do they supply water but they also offer services for humanity. Despite a growing recognition towards IRES, information for assessing their ecosystem services (ES) remains scarce. In a first step, an international interdisciplinary group of researchers developed a methodological framework to acknowledge ES provided by IRES using 109 indicators. A subset of selected ES indicators was then applied to two case studies: the Rio Seco in the Algarve (Portugal) and the Giofyros River in Crete (Greece). This paper discusses the applicability of these indicators, including the temporal and spatial variability of IRES flow regimes. Aspects of the framework, such as the methods and time required for data collection, the nature (demand or supply) and functionality of each indicator are discussed. The new framework accounts for flow intermittence in ES analyses and can help scientists and water managers to i) increase the ease and justification for IRES use in management approaches and ii) improve their conservation and restoration with a comprehensive set of appropriate indicators for IRES. In addition, the comprehensive nature of the proposed indicators ensures that they can be understood by a broad audience and easily applicable. Since they were designed through a public participation process, the setting has been prepared for holistic stakeholder analysis and education around IRES functions and associated ES. From a management point of view, it would be particularly relevant to perform an economic evaluation with this new framework to understand the value of each ES category and their trade-offs. For the scientific community, however, it is important to consider public preferences to design socially accepted policies. The proposed indicators can successfully bridge these elements, hereby establishing a solid basis for the assessment of ES provided by IRES.</p

River ecosystem conceptual models and non-perennial rivers: A critical review

Conceptual models underpin river ecosystem research. However, current models focus on continuously flowing rivers and few explicitly address characteristics such as flow cessation and drying. The applicability of existing conceptual models to nonperennial rivers that cease to flow (intermittent rivers and ephemeral streams, IRES) has not been evaluated. We reviewed 18 models, finding that they collectively describe main drivers of biogeochemical and ecological patterns and processes longitudinally (upstream-downstream), laterally (channel-riparian-floodplain), vertically (surface water-groundwater), and temporally across local and landscape scales. However, perennial rivers are longitudinally continuous while IRES are longitudinally discontinuous. Whereas perennial rivers have bidirectional lateral connections between aquatic and terrestrial ecosystems, in IRES, this connection is unidirectional for much of the time, from terrestrial-to-aquatic only. Vertical connectivity between surface and subsurface water occurs bidirectionally and is temporally consistent in perennial rivers. However, in IRES, this exchange is temporally variable, and can become unidirectional during drying or rewetting phases. Finally, drying adds another dimension of flow variation to be considered across temporal and spatial scales in IRES, much as flooding is considered as a temporally and spatially dynamic process in perennial rivers. Here, we focus on ways in which existing models could be modified to accommodate drying as a fundamental process that can alter these patterns and processes across spatial and temporal dimensions in streams. This perspective is needed to support river science and management in our era of rapid global change, including increasing duration, frequency, and occurrence of drying

A prognostic score to identify low-risk outpatients with acute deep vein thrombosis in the lower limbs

BACKGROUND: No prior studies have identified which patients with deep vein thrombosis in the lower limbs are at a low risk for adverse events within the first week of therapy. METHODS: We used data from the Registro Informatizado de la Enfermedad TromboEmb\uf3lica (RIETE) to identify patients at low risk for the composite outcome of pulmonary embolism, major bleeding, or death within the first week. We built a prognostic score and compared it with the decision to treat patients at home. RESULTS: As of December 2013, 15,280 outpatients with deep vein thrombosis had been enrolled. Overall, 5164 patients (34%) were treated at home. Of these, 12 (0.23%) had pulmonary embolism, 8 (0.15%) bled, and 4 (0.08%) died. On multivariable analysis, chronic heart failure, recent immobility, recent bleeding, cancer, renal insufficiency, and abnormal platelet count independently predicted the risk for the composite outcome. Among 11,430 patients (75%) considered to be at low risk, 15 (0.13%) suffered pulmonary embolism, 22 (0.19%) bled, and 8 (0.07%) died. The C-statistic was 0.61 (95% confidence interval [CI], 0.57-0.65) for the decision to treat patients at home and 0.76 (95% CI, 0.72-0.79) for the score (P = .003). Net reclassification improvement was 41% (P < .001). Integrated discrimination improvement was 0.034 for the score and 0.015 for the clinical decision (P < .001). CONCLUSIONS: Using 6 easily available variables, we identified outpatients with deep vein thrombosis at low risk for adverse events within the first week. These data may help to safely treat more patients at home. This score, however, should be validated

Long-term anticoagulant therapy of patients with venous thromboembolism. What are the practices?

Current guidelines of antithrombotic therapy suggest early initiation of vitamin K antagonists (VKA) in non-cancer patients with venous thromboembolism (VTE), and long-term therapy with low-molecular weight heparin (LMWH) for those with cancer. We used data from RIETE (international registry of patients with VTE) to report the use of long-term anticoagulant therapy over time and to identify predictors of anticoagulant choice (regarding international guidelines) in patients with- and without cancer. Among 35,280 patients without cancer, 82% received long-term VKA (but 17% started after the first week). Among 4,378 patients with cancer, 66% received long term LMWH as monotherapy. In patients without cancer, recent bleeding (odds ratio [OR] 2.70, 95% CI 2.26-3.23), age >70 years (OR 1.15, 95% CI 1.06-1.24), immobility (OR 2.06, 95% CI 1.93-2.19), renal insufficiency (OR 2.42, 95% CI 2.15-2.71) and anemia (OR 1.75, 95% CI 1.65-1.87) predicted poor adherence to guidelines. In those with cancer, anemia (OR 1.83, 95% CI 1.64-2.06), immobility (OR 1.51, 95% CI 1.30-1.76) and metastases (OR 3.22, 95% CI 2.87-3.61) predicted long-term LMWH therapy. In conclusion, we report practices of VTE therapy in real life and found that a significant proportion of patients did not receive the recommended treatment. The perceived increased risk for bleeding has an impact on anticoagulant treatment decision

Clinical outcome in patients with venous thromboembolism receiving concomitant anticoagulant and antiplatelet therapy

Introduction: Patients with arterial disease receiving antiplatelet agents may develop venous thromboembolism (VTE) and need anticoagulant therapy, although concomitant use of these drugsmay increase bleeding risk. We analyzed RIETE data and compared clinical outcomes depending on decision to discontinue or maintain antiplatelet therapy at VTE diagnosis. Methods: Consecutive patients with acute VTE were enrolled in RIETE. Only patients receiving antiplatelet therapy at baseline were included in this analysis. Primary outcomes were: rate of subsequent ischemic events, major bleeding or death during anticoagulation course. Results: 1178 patientswho received antiplatelet drugs at VTE diagnosis were included. Antiplatelet therapy was discontinued in 62% of patients. During anticoagulation course, patients also receiving antiplatelet therapy had higher rates of lower limb amputations (2.28 vs. 0.21 events per 100 patients-years; p < 0.01), any ischemic events (5.7 vs. 2.28 events per 100 patients-years; p < 0.05) or death (23.6 vs. 13.9 deaths per 100 patientsyears; p < 0.01). No differences in the rate of major bleeding or recurrent VTEwere revealed. In matched analysis, patients on antiplatelet therapy were found to have a significantly higher rate of limb amputations (odds ratio: 15.3; 95% CI: 1.02-229) and an increased number of composite outcomes including all-cause deaths, arterial and VTE events (odds ratio: 1.46; CI: 1.03-2.06), with no differences in major bleeding rate. Conclusion: Concomitant anticoagulant and antiplatelet therapy in patients with VTE and arterial disease is not associated with increased risk for bleeding, recurrent VTE or death. The worse outcome observed in patients who continued antiplatelet therapy requires further investigations

Influence of recent immobilization or surgery on mortality in cancer patients with venous thromboembolism

BACKGROUND: The influence of recent immobilization or surgery on mortality in cancer patients with venous thromboembolism (VTE) has not been thoroughly studied. METHODS: We used the RIETE Registry data to compare the 3-month mortality rate in cancer patients with VTE, with patients categorized according to the presence of recent immobilization, surgery or neither. The major outcomes were fatal pulmonary embolism (PE) and fatal bleeding within the first 3 months. RESULTS: Of 6,746 patients with active cancer and acute VTE, 1,224 (18%) had recent immobilization, 1,055 (16%) recent surgery, and 4,467 (66%) had neither. The all-cause mortality was 23.4% (95% CI: 22.4-24.5), and the PE-related mortality: 2.5% (95% CI: 2.1-2.9). Four in every ten patients dying of PE had recent immobilization (37%) or surgery (5.4%). Only 28% of patients with immobilization had received prophylaxis, as compared with 67% of the surgical. Fatal PE was more common in patients with recent immobilization (5.0%; 95% CI: 3.9-6.3) than in those with surgery (0.8%; 95% CI: 0.4-1.6) or neither (2.2%; 95% CI: 1.8-2.6). On multivariate analysis, patients with immobilization were at an increased risk for fatal PE (odds ratio: 1.8; 95% CI: 1.2-2.5). CONCLUSIONS: One in every three cancer patients dying of PE had recent immobilization for ≥ 4 days. Many of these deaths could have been prevented with adequate thromboprophylaxis

Rivaroxaban with or without aspirin in stable cardiovascular disease

BACKGROUND: We evaluated whether rivaroxaban alone or in combination with aspirin would be more effective than aspirin alone for secondary cardiovascular prevention. METHODS: In this double-blind trial, we randomly assigned 27,395 participants with stable atherosclerotic vascular disease to receive rivaroxaban (2.5 mg twice daily) plus aspirin (100 mg once daily), rivaroxaban (5 mg twice daily), or aspirin (100 mg once daily). The primary outcome was a composite of cardiovascular death, stroke, or myocardial infarction. The study was stopped for superiority of the rivaroxaban-plus-aspirin group after a mean follow-up of 23 months. RESULTS: The primary outcome occurred in fewer patients in the rivaroxaban-plus-aspirin group than in the aspirin-alone group (379 patients [4.1%] vs. 496 patients [5.4%]; hazard ratio, 0.76; 95% confidence interval [CI], 0.66 to 0.86; P<0.001; z=−4.126), but major bleeding events occurred in more patients in the rivaroxaban-plus-aspirin group (288 patients [3.1%] vs. 170 patients [1.9%]; hazard ratio, 1.70; 95% CI, 1.40 to 2.05; P<0.001). There was no significant difference in intracranial or fatal bleeding between these two groups. There were 313 deaths (3.4%) in the rivaroxaban-plus-aspirin group as compared with 378 (4.1%) in the aspirin-alone group (hazard ratio, 0.82; 95% CI, 0.71 to 0.96; P=0.01; threshold P value for significance, 0.0025). The primary outcome did not occur in significantly fewer patients in the rivaroxaban-alone group than in the aspirin-alone group, but major bleeding events occurred in more patients in the rivaroxaban-alone group. CONCLUSIONS: Among patients with stable atherosclerotic vascular disease, those assigned to rivaroxaban (2.5 mg twice daily) plus aspirin had better cardiovascular outcomes and more major bleeding events than those assigned to aspirin alone. Rivaroxaban (5 mg twice daily) alone did not result in better cardiovascular outcomes than aspirin alone and resulted in more major bleeding events