2,519 research outputs found

    Factors contributing to carbon fluxes from bioenergy harvests in the U.S. Northeast: An analysis using field data

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    With growing interest in wood bioenergy there is uncertainty over greenhouse gas emissions associated with offsetting fossil fuels. Although quantifying postharvest carbon (C) fluxes will require accurate data, relatively few studies have evaluated these using field data from actual bioenergy harvests. We assessed C reductions and net fluxes immediately postharvest from whole-tree harvests (WTH), bioenergy harvests without WTH, and nonbioenergy harvests at 35 sites across the northeastern United States. We compared the aboveground forest C in harvested with paired unharvested sites, and analyzed the C transferred to wood products and C emissions from energy generation from harvested sites, including indirect emissions from harvesting, transporting, and processing. All harvests reduced live tree C; however, only bioenergy harvests using WTH significantly reduced C stored in snags (P \u3c 0.01). On average, WTH sites also decreased downed coarse woody debris C while the other harvest types showed increases, although these results were not statistically significant. Bioenergy harvests using WTH generated fewer wood products and resulted in more emissions released from bioenergy than the other two types of harvests, which resulted in a greater net flux of C (P \u3c 0.01). A Classification and Regression Tree analysis determined that it was not the type of harvest or amount of bioenergy generated, but rather the type of skidding machinery and specifics of silvicultural treatment that had the largest impact on net C flux. Although additional research is needed to determine the impact of bioenergy harvesting over multiple rotations and at landscape scales, we conclude that operational factors often associated with WTH may result in an overall intensification of C fluxes. The intensification of bioenergy harvests, and subsequent C emissions, that result from these operational factors could be reduced if operators select smaller equipment and leave a portion of tree tops on site. Copyright © 2013

    Net carbon fluxes at stand and landscape scales from wood bioenergy harvests in the US Northeast

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    The long-term greenhouse gas emissions implications of wood biomass (\u27bioenergy\u27) harvests are highly uncertain yet of great significance for climate change mitigation and renewable energy policies. Particularly uncertain are the net carbon (C) effects of multiple harvests staggered spatially and temporally across landscapes where bioenergy is only one of many products. We used field data to formulate bioenergy harvest scenarios, applied them to 362 sites from the Forest Inventory and Analysis database, and projected growth and harvests over 160 years using the Forest Vegetation Simulator. We compared the net cumulative C fluxes, relative to a non-bioenergy baseline, between scenarios when various proportions of the landscape are harvested for bioenergy: 0% (non-bioenergy); 25% (BIO25); 50% (BIO50); or 100% (BIO100), with three levels of intensification. We accounted for C stored in aboveground forest pools and wood products, direct and indirect emissions from wood products and bioenergy, and avoided direct and indirect emissions from fossil fuels. At the end of the simulation period, although 82% of stands were projected to maintain net positive C benefit, net flux remained negative (i.e., net emissions) compared to non-bioenergy harvests for the entire 160-year simulation period. BIO25, BIO50, and BIO100 scenarios resulted in average annual emissions of 2.47, 5.02, and 9.83 Mg C ha-1, respectively. Using bioenergy for heating decreased the emissions relative to electricity generation as did removing additional slash from thinnings between regeneration harvests. However, all bioenergy scenarios resulted in increased net emissions compared to the non-bioenergy harvests. Stands with high initial aboveground live biomass may have higher net emissions from bioenergy harvest. Silvicultural practices such as increasing rotation length and structural retention may result in lower C fluxes from bioenergy harvests. Finally, since passive management resulted in the greatest net C storage, we recommend designation of unharvested reserves to offset emissions from harvested stands

    Kliniczne metody oceny pacjentów z chromaniem przestankowym

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    W pracy przedstawiono wybrane metody oceny klinicznej pacjentów z chromaniem przestankowym. Metody te obejmują podstawowe pomiary hemodynamiczne, ocenę możliwości fizycznych pacjenta oraz badania kwestionariuszowe. Stosowane badania służą zarówno diagnostyce chromania, jak również ocenie skuteczności stosowanej terapii, a także charakteryzują stan funkcjonalny i jakość życia chorych. Heterogenny charakter opisywanej grupy pacjentów oraz związane z chorobą znaczne ograniczenie aktywnego uczestnictwa chorego w życiu społecznym i zawodowym wymaga użycia miar rzetelnych, całościowo opisujących stopień zaawansowania choroby, jak również jej wpływ na codzienne funkcjonowanie i jakość życia pacjentów. Na ogół odosobnione pomiary hemodynamiczne nie są właściwą metodą oceny a ich wartości nie korelują z możliwościami funkcjonalnymi pacjentów z chromaniem przestankowym. Podobnie, poprawa możliwości wysiłkowych, obserwowana podczas treningu, nie zawsze odzwierciedla się w poprawie wartości parametrów hemodynamicznych. Stąd też, w diagnostyce chorych z chromaniem przestankowym zaleca się stosowanie złożonych metod oceny. Celem pracy była zarówno ocena skuteczności metod najczęściej stosowanych w diagnostyce chorych z chromaniem przestankowym, jak i próba wskazania najbardziej przydatnych, zarówno dla celów klinicznych jak i badań naukowych.In this work there are presented different methods of clinical analysis of patients with intermittent claudication. The methods contain haemodynamic measurements, an assessment of physiological parameters, an assessment of the physical abilities of a patient and questionnaires’ assessment. These methods are used for diagnosis o f intermittent claudication, the evaluation of patients’ condition after therapy as well as for describing patients’ functional performance and their quality of living. Because of the heterogenic character of patients with intermittent claudication and their serious limitations in personal, vocational and social life, the parameters used for patient’s characterization have to be reliable, complex, describing not only the progress of the disease but also its influence on everyday life and quality of life. Isolated haemodynamic measurements are not a proper method of a patient’s evaluation, their values do not correlate with the functional performance of patients. Similarly, the improvement of physical abilities that is seen during trainings, is not always visible in the values of the haemodynamic parameters. These reasons indicate that a complex clinical analysis of different parameters in patients with intermittent claudication is strongly advisable. The aim of this study was to assess the effectiveness of the most common methods that are used in the diagnosis of patients suffering from intermittent claudication, with the indication of those that may be the most important for clinical and scientific research

    Instructions for external emergency plan exercises

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    Enligt 48 § i räddningslagen (379/2011) och inrikesministeriets förordning om externa räddningsplaner ska räddningsverket med minst tre års mellanrum öva i objekt med risk för storolycka. Sådana objekt är t.ex. produktionsanläggningar för hantering och upplagring av farliga kemikalier, bangårdar, hamnområden, kärnkraftverk och deponier för utvinningsavfall. I Finland finns det ca 200 objekt som är skyldiga att göra upp en extern räddningsplan och öva regelbundet. Genom anvisningen förenhetligas och förtydligas planeringen, genomförandet, utvärderingen och rapporteringen av övningar som gäller externa räddningsplaner i objekt enligt 48 § i räddningslagen. I anvisningen kallas övningen på finska UPS-harjoitus (övning enligt extern räddningsplan). Räddningsverken ansvarar för uppgörandet av externa räddningsplaner och ordnandet av övningar enligt extern räddningsplan, detta i samarbete med verksamhetsidkaren. Regionförvaltningsverken har till uppgift att övervaka att skyldigheterna fullgörs. Finland har enligt Seveso III-direktivet och direktivet om hantering av avfall från utvinningsindustrin en skyldighet att rapportera om planerna och övningsverksamheten till Europeiska kommissionen. För att genomföra övningarna enligt externa räddningsplaner finns det flera skeden i processen. Övningsprocessen består av planering, beredning och genomförande av övningen samt av utvecklingsåtgärder. Syftet med anvisningen är att förenhetliga övningsverksamheten enligt räddningsverkens externa räddningsplaner och att förtydliga kraven på övningar

    Risk factors for adverse outcomes in vaginal preterm breech labor

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    cited By 0Purpose To assess the risk factors for adverse outcomes in attempted vaginal preterm breech deliveries. Methods A retrospective case-control study, including 2312 preterm breech deliveries (24 + 0 to 36 + 6 gestational weeks) from 2004 to 2018 in Finland. The preterm breech fetuses with adverse outcomes born vaginally or by emergency cesarean section were compared with the fetuses without adverse outcomes with the same gestational age. A multivariable logistic regression analysis was used to calculate the risk factors for adverse outcomes (umbilical arterial pH below 7, 5-min Apgar score below 4, intrapartum stillbirth and neonatal death <28 days of age). Results Adverse outcome in vaginal preterm breech delivery was associated with maternal obesity (aOR 32.19, CI 2.97-348.65), smoking (aOR 2.29, CI 1.12-4.72), congenital anomalies (aOR 4.50, 1.56-12.96), preterm premature rupture of membranes (aOR 1.87, CI 1.00-3.49), oligohydramnios (28-32 weeks of gestation: aOR 6.50, CI 2.00-21.11, 33-36 weeks of gestation: aOR 19.06, CI 7.15-50.85), epidural anesthesia in vaginal birth (aOR 2.44, CI 1.19-5.01), and fetal growth below the second standard deviation (28-32 weeks of gestation: aOR 5.89, CI 1.00-34.74, 33-36 weeks of gestation: aOR 12.27, CI 2.81-53.66). Conclusion The study shows that for each subcategory of preterm birth, there are different risk factors for adverse neonatal outcomes in planned vaginal breech delivery. Due to the extraordinary increased risk of adverse outcomes, we would recommend a planned cesarean section in very preterm breech presentation (28 + 0 to 32 + 6 weeks) with severe maternal obesity, oligohydramnios, or fetal growth restriction and in moderate to late preterm breech presentation (33 + 0 to 36 + 6 weeks) with oligohydramnios or fetal growth restriction.Peer reviewe
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