89 research outputs found
Potential role for clinical calibration to increase engagement with and application of home telemonitoring: a report from the HeartCycle programme
Aims: There is a need for alternative strategies that might avoid recurrent admissions in patients with heart failure. Home Telemonitoring (HTM) to monitor patientâs symptoms from a distance may be useful. This study attempts to assess changes in HTM vital signs in response to daily life activities (variations in medication, salt intake, exercise and stress) and to stablish which variations affect weight, blood pressure (BP) and heart rate (HR). Methods and results: We assessed 76 patients with heart failure (mean age 76 ± 10.8 years, 75% male, mainly in NYHA class II/III and from ischaemic etiology cause). Patients were given a calendar of interventions scheduling activities approximately twice-a-week before measuring their vital signs. Eating salty food or a large meal were the activities that had a significant impact on weight gain (+0.3 kg; p<0.001 and p=0.006, respectively). Exercise and skipping a dose of medication other than diuretics increased heart rate (+3 bpm, p=0.001 and almost +2 bpm, p=0.016, respectively). Conclusions: Our HTM system was able to detect small changes in vital signs related to these activities. Further studies should assess if providing such a schedule of activities might be useful for patient education and could improve long-term adherence to recommended lifestyle changes
Digital, memory and mixed-signal test engineering education: five centres of competence in Europe
The launching of the EuNICE-Test project was announced two years ago at the first DELTA Conference. This project is now completed and the present paper describes the project actions and outcomes. The original idea was to build a long-lasting European Network for test engineering education using both test resource mutualisation and remote experiments. This objective is fully fulfilled and we have now, in Europe, five centres of competence able to deliver high-level and high-specialized training courses in the field of test engineering using a high-performing industrial ATE. All the centres propose training courses on digital testing, three of them propose mixed-signal trainings and three of them propose memory trainings. Taking into account the demand in test engineering, the network is planned to continue in a stand alone mode after project end. Nevertheless a new European proposal with several new partners and new test lessons is under construction
Riparian evapotranspiration is essential to simulate streamflow dynamics and water budgets in a Mediterranean catchment
Riparian trees can regulate streamflow dynamics and water
budgets by taking up large amounts of water from both soil and groundwater
compartments. However, their role has not been fully recognized in the
hydrologic literature and the catchment modeling community. In this study, we
explored the influence of riparian evapotranspiration (ET) on streamflow by
simulating daily stream water exports from three nested Mediterranean
catchments, both including and excluding the riparian compartment in the
structure of the PERSiST (Precipitation, Evapotranspiration and Runoff
Simulator for Solute Transport) rainfallârunoff model. The model goodness of fit for the calibration period
(September 2010âAugust 2012) significantly improved with the inclusion of
the riparian compartment, especially during the vegetative period, when
according to our simulations, the riparian zone significantly reduced the
overestimation of mean daily streamflow (from 53 % to 27 %). At the
catchment scale, simulated riparian ET accounted for 5.5 % to 8.4 % of
annual water depletions over a 20-year reference period (1981â2000), and its
contribution was especially noticeable during summer (from 8 % to 26 %).
Simulations considering climate change scenarios suggest large increases in
riparian ET during the dormant period (from 19 % to 46 %) but only small
increases (from 1 % to 2 %) in its contribution to annual water budgets.
Overall, our results highlight that a good assessment of riparian ET is
essential for understanding catchment hydrology and streamflow dynamics in
Mediterranean regions. Thus, the inclusion of the riparian compartment in
hydrological models is strongly recommended in order to establish proper
management strategies in water-limited regions.</p
Unraveling the Molecular Mechanism of Action of Empagliflozin in Heart Failure With Reduced Ejection Fraction With or Without Diabetes
he mechanism of action of empagliflozin in heart failure with reduced ejection fraction (HFrEF) was deciphered using deep learning in silico analyses together with in vivo validation. The most robust mechanism of action involved the sodium-hydrogen exchanger (NHE)-1 co-transporter with 94.7% accuracy, which was similar for diabetics and nondiabetics. Notably, direct NHE1 blockade by empagliflozin ameliorated cardiomyocyte cell death by restoring expression of X-linked inhibitor of apoptosis (XIAP) and baculoviral IAP repeat-containing protein 5 (BIRC5). These results were independent of diabetes mellitus comorbidity, suggesting that empagliflozin may emerge as a new treatment in HFrEF
Behind the scenes: mechanisms regulating climatic patterns of dissolved organic carbon uptake in headwater streams
Large variability in dissolved organic carbon (DOC) uptake rates has been reported for headwater streams, but the causes of this variability are still not well understood. Here we assessed acetate uptake rates across 11 European streams comprising different ecoregions by using whole-reach pulse acetate additions. We evaluated the main climatic and biogeochemical drivers of acetate uptake during two seasonal periods. Our results show a minor influence of sampling periods but a strong effect of climate and dissolved organic matter (DOM) composition on acetate uptake. In particular, mean annual precipitation explained half of the variability of the acetate uptake velocities (VfAcetate) across streams. Temperate streams presented the lowest VfAcetate, together with humic-like DOM and the highest stream respiration rates. In contrast, higher VfAcetate were found in semiarid streams, with protein-like DOM, indicating a dominance of reactive, labile compounds. This, together with lower stream respiration rates and molar ratios of DOC to nitrate, suggests a strong C limitation in semiarid streams, likely due to reduced inputs from the catchment. Overall, this study highlights the interplay of climate and DOM composition and its relevance to understand the biogeochemical mechanisms controlling DOC uptake in streams.Theauthors were supported by the following funding: N. C. by a Generalitat de Catalunya-Beatriu de PinĂłs grant
(BP2016â00215), E. E. by a predoctoral grant from the Basque Government, A. G. B. by a Generalitat de Catalunya-Beatriu de PinĂłs (BP-00385-2016), A. M. G. F. by a predoctoral research grant (BES-2013-065770) from the Spanish Ministry of Economy and Competitiveness, P. R. L. by a RamĂłn Areces Foundation Postdoctoral
Scholarship, and A. L. by a Kempe Foundation stipend. DOMIPEX project was funded by the First Call of Collaborative Projects among Young Researchers of the Iberian Association of Limnology (AIL; 2013â2015)
Advancing river corridor science beyond disciplinary boundaries with an inductive approach to catalyse hypothesis generation
A unified conceptual framework for river corridors requires synthesis of diverse site-, method- and discipline-specific findings. The river research community has developed a substantial body of observations and process-specific interpretations, but we are still lacking a comprehensive model to distill this knowledge into fundamental transferable concepts. We confront the challenge of how a discipline classically organized around the deductive model of systematically collecting of site-, scale-, and mechanism-specific observations begins the process of synthesis. Machine learning is particularly well-suited to inductive generation of hypotheses. In this study, we prototype an inductive approach to holistic synthesis of river corridor observations, using support vector machine regression to identify potential couplings or feedbacks that would not necessarily arise from classical approaches. This approach generated 672 relationships linking a suite of 157 variables each measured at 62 locations in a fifth order river network. Eighty four percent of these relationships have not been previously investigated, and representing potential (hypothetical) process connections. We document relationships consistent with current understanding including hydrologic exchange processes, microbial ecology, and the River Continuum Concept, supporting that the approach can identify meaningful relationships in the data. Moreover, we highlight examples of two novel research questions that stem from interpretation of inductively-generated relationships. This study demonstrates the implementation of machine learning to sieve complex data sets and identify a small set of candidate relationships that warrant further study, including data types not commonly measured together. This structured approach complements traditional modes of inquiry, which are often limited by disciplinary perspectives and favour the careful pursuit of parsimony. Finally, we emphasize that this approach should be viewed as a complement to, rather than in place of, more traditional, deductive approaches to scientific discovery
Prognostic value of simple frailty and malnutrition screening tools in patients with acute heart failure due to left ventricular systolic dysfunction
Background:
Frailty and malnutrition are common in patients with heart failure (HF), and are associated with adverse outcomes. We studied the prognostic value of three malnutrition and three frailty indices in patients admitted acutely to hospital with HF.
Methods:
265 consecutive patients [62% males, median age 80 (interquartile range (IQR): 72â86) years, median NTproBNP 3633 (IQR: 2025â6407) ng/l] admitted with HF between 2013 and 2014 were enrolled. Patients were screened for frailty using the Derby frailty index (DFI), acute frailty network (AFN) frailty criteria, and clinical frailty scale (CFS) and for malnutrition using the geriatric nutritional risk index (GNRI), controlling nutritional status (CONUT) score and prognostic nutritional index (PNI).
Results:
According to the CFS (>â4), DFI, and AFN, 53, 50, and 53% were frail, respectively. According to the GNRI (â€â98), CONUT score (>â4), and PNI (â€â38), 46, 46, and 42% patients were malnourished, respectively. During a median follow-up of 598 days (IQR 319â807 days), 113 patients died. One year mortality was 1% for those who were neither frail nor malnourished; 15% for those who were either malnourished or frail; and 65% for those who were both malnourished and frail. Amongst the malnutrition scores, PNI, and amongst the frailty scores, CFS increased model performance most compared with base model. A final model, including CFS and PNI, increased c-statistic for mortality prediction from 0.68 to 0.84.
Conclusion:
Worsening frailty and malnutrition indices are strongly related to worse outcome in patients hospitalised with HF
Revisiting the obesity paradox in heart failure:Per cent body fat as predictor of biomarkers and outcome
Aims
- Obesity defined by body mass index (BMI) is characterized by better prognosis and lower plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) in heart failure. We assessed whether another anthropometric measure, per cent body fat (PBF), reveals different associations with outcome and heart failure biomarkers (NT-proBNP, high-sensitivity troponin T (hs-TnT), soluble suppression of tumorigenesis-2 (sST2)).
Methods
- In an individual patient dataset, BMI was calculated as weight (kg)/height (m)2, and PBF through the JacksonâPollock and Gallagher equations.
Results
- Out of 6468 patients (median 68 years, 78% men, 76% ischaemic heart failure, 90% reduced ejection fraction), 24% died over 2.2 years (1.5â2.9), 17% from cardiovascular death. Median PBF was 26.9% (22.4â33.0%) with the JacksonâPollock equation, and 28.0% (23.8â33.5%) with the Gallagher equation, with an extremely strong correlation (râ=â0.996, pâ2, third PBF tertile), hs-TnT and sST2, but not NT-proBNP, independently predicted outcome.
Conclusion
- In parallel with increasing BMI or PBF there is an improvement in patient prognosis and a decrease in NT-proBNP, but not hs-TnT or sST2. hs-TnT or sST2 are stronger predictors of outcome than NT-proBNP among obese patients
CA125-Guided Diuretic Treatment Versus Usual Care in Patients With Acute Heart Failure and Renal Dysfunction
Background: The optimal diuretic treatment strategy for patients with acute heart failure and renal dysfunction remains unclear. Plasma carbohydrate antigen 125 (CA125) is a surrogate of fluid overload and a potentially valuable tool for guiding decongestion therapy. The aim of this study was to determine if a CA125-guided diuretic strategy is superior to usual care in terms of short-term renal function in patients with acute heart failure and renal dysfunction at presentation. Methods: This multicenter, open-label study randomized 160 patients with acute heart failure and renal dysfunction into 2 groups (1:1). Loop diuretics doses were established according to CA125 levels in the CA125-guided group (n = 79) and in clinical evaluation in the usual-care group (n = 81). Changes in estimated glomerular filtration rate (eGFR) at 72 and 24 hours were the co-primary endpoints, respectively. Results: The mean age was 78 ± 8 years, the median amino-terminal pro-brain natriuretic peptide was 7765 pg/mL, and the mean eGFR was 33.7 ± 11.3 mL/min/1.73m2. Over 72 hours, the CA125-guided group received higher furosemide equivalent dose compared to usual care (P = 0.011), which translated into higher urine volume (P = 0.042). Moreover, patients in the active arm with CA125 >35 U/mL received the highest furosemide equivalent dose (P <0.001) and had higher diuresis (P = 0.013). At 72 hours, eGFR (mL/min/1.73m2) significantly improved in the CA125-guided group (37.5 vs 34.8, P = 0.036), with no significant changes at 24 hours (35.8 vs 39.5, P = 0.391). Conclusion: A CA125-guided diuretic strategy significantly improved eGFR and other renal function parameters at 72 hours in patients with acute heart failure and renal dysfunction
Unexpected large evasion fluxes of carbon dioxide from turbulent streams draining the worldâs mountains
Inland waters, including streams and rivers, are active components of the global carbon cycle. Despite the large areal extent of the worldâs mountains, the role of mountain streams for global carbon fluxes remains elusive. Using recent insights from gas exchange in turbulent streams, we found that areal CO2 evasion fluxes from mountain streams equal or exceed those reported from tropical and boreal streams, typically regarded as hotspots of aquatic carbon fluxes. At the regional scale of the Swiss Alps, we present evidence that emitted CO2 derives from lithogenic and biogenic sources within the catchment and delivered by the groundwater to the streams. At a global scale, we estimate the CO2 evasion from mountain streams to 167 ± 1.5 Tg C yrâ1, which is high given their relatively low areal contribution to the global stream and river networks. Our findings shed new light on mountain streams for global carbon fluxes
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