1,105 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

    A comparison of risk factors for breech presentation in preterm and term labor : a nationwide, population-based case-control study

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    Purpose To determine if the common risks for breech presentation at term labor are also eligible in preterm labor. Methods A Finnish cross-sectional study included 737,788 singleton births (24-42 gestational weeks) during 2004-2014. A multivariable logistic regression analysis was used to calculate the risks of breech presentation. Results The incidence of breech presentation at delivery decreased from 23.5% in pregnancy weeks 24-27 to 2.5% in term pregnancies. In gestational weeks 24-27, preterm premature rupture of membranes was associated with breech presentation. In 28-31 gestational weeks, breech presentation was associated with maternal pre-eclampsia/hypertension, preterm premature rupture of membranes, and fetal birth weight below the tenth percentile. In gestational weeks 32-36, the risks were advanced maternal age, nulliparity, previous cesarean section, preterm premature rupture of membranes, oligohydramnios, birth weight below the tenth percentile, female sex, and congenital anomaly. In term pregnancies, breech presentation was associated with advanced maternal age, nulliparity, maternal hypothyroidism, pre-gestational diabetes, placenta praevia, premature rupture of membranes, oligohydramnios, congenital anomaly, female sex, and birth weight below the tenth percentile. Conclusion Breech presentation in preterm labor is associated with obstetric risk factors compared to cephalic presentation. These risks decrease linearly with the gestational age. In moderate to late preterm delivery, breech presentation is a high-risk state and some obstetric risk factors are yet visible in early preterm delivery. Breech presentation in extremely preterm deliveries has, with the exception of preterm premature rupture of membranes, similar clinical risk profiles as in cephalic presentation.Peer reviewe

    Prevalence of overweight in 2 to 17 year-old children and adolescents whose parents live separately: a Nordic cross-sectional study

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    Background Comparative data of parental separation and childhood overweight has not been available before across the Nordic countries. The aim of this study was to examine the within-country prevalence and association between parental cohabitation and overweight in Nordic children. Methods A cross-sectional survey of 2-17-year-old children was conducted in 2011, titled: “NordChild”. A random sample of 3,200 parents in each of the Nordic countries (Denmark, Finland, Iceland, Norway, and Sweden were invited to participate in the study with parents of 6,609 children accepting to give answers about their children’s health and welfare including information on height and weight of each child and parental cohabitation (response rate 41.5%). The group differences in prevalence and adjusted odds ratio (OR) for overweight, with corresponding 95% confidence intervals (CI) were performed in children whose parents lived separately. Additionally, a missing data analysis was performed to determine whether the adjusted estimates might result from confounding or selection bias. Results A significant difference was observed in Iceland between children whose parents live separately compared to those who live with both parents (difference: 9.4%, 95% CI: 2.8; 15.9) but no such difference was observed in Denmark, Finland, Norway and Sweden. No significant odds of overweight were observed in children whose parents lived separately compared to children in normal weight at the time of study; Denmark: OR 1.03 (95% CI: 0.42; 2.53), Finland: OR 1.27 (95% CI: 0.74; 2.20), Iceland: OR 1.50 (95% CI: 0.79; 2.84), Norway: OR 1.46 (95% CI: 0.81; 2.62), and Sweden: 1.07 (95% CI: 0.61; 1.86). The missing data analysis indicated that the findings in Norway, Finland and Iceland were partly observed due to selection effects, whereas the adjustment in Denmark was due to confounding. The crude OR for overweight was higher in the 2-9-year-old group than in the 10-17-year-old group whose parents lived separately in Iceland, Norway and Sweden. Conclusions No association between parental cohabitation and overweight in Nordic children was found. Our finding of greater prevalence of overweight in Icelandic children whose parents live separately may be an indication that the welfare system in Iceland is separating from the other Nordic countries

    Development of office-hours use of primary health centers in the early years of the 21st century : a 13-year longitudinal follow-up study

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    This study, conducted in a Finnish city, examined whether a long-lasting observed trend in Finnish primary health care, namely, a decreasing rate of office-hour visits to general practitioners (GPs), would lead to reduced services for specific gender, diagnosis or age groups. This was an observational retrospective follow-up study. The annual number of visits to office-hour primary care GPs in different gender, diagnosis and age groups was recorded during a 13-year follow-up period. The effect of the decreasing visit rate on the annual mortality rate in different age and gender groups was also studied. The total number of monthly visits to office-hour GPs decreased slowly over the whole study period. This decrease was stronger in women and older people. The proportion of recorded infectious diseases (Groups A and J and especially diagnoses related to infections of respiratory airways) decreased. Proportions of recorded chronic diseases increased (Group I, cardiovascular diseases, diabetes and osteoarthrosis) during the follow-up. The annual rate of visits to office-hour GP/per GP decreased. There was a decrease in the mortality in two of the age groups (20-64, 65+ years) and no change in the youngest population (0-19 years). The decrease in the office-hours GP activity does not seem to increase mortality either.Peer reviewe

    Development of the use of primary health care emergency departments after interventions aimed at decreasing overcrowding : a longitudinal follow-up study

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    Background This study, conducted in a Finnish city, examined whether decreasing emergency department (ED) services in an overcrowded primary care ED and corresponding direction to office-hours primary care would modify service usage for specific gender, age or diagnosis groups. Methods This was an observational retrospective study carried out by gradually decreasing ED services in primary care. The interventions aimed at decreasing use of EDs were a) application of ABCDE-triage combined with public guidance on the proper use of EDs, b) closure of a minor supplementary ED, and finally, c) application of "reverse triage" with enhanced direction of the public to office-hours services and away from the remaining ED The annual number of visits to office-hours primary care GPs in different gender, age and diagnosis groups (International Classification of Diseases (ICD - 10) were recorded during a 13-year follow-up period. Results The total number of monthly visits to EDs decreased slowly over the whole study period. This decrease was similar in women and men. The decrease was stronger in the youngest age groups (0-19 years). GPs treated decreasing proportions of ICD-10 groups. Recorded infectious diseases (Groups A and J, and especially diagnoses related to infections of respiratory airways) tended to decrease. However, visits due to injuries and symptomatic diagnoses increased. Conclusion Decreasing services in a primary health care ED with the described interventions seemed to reduce the use of services by young people. The three interventions mentioned above had the effect of making the primary care ED under study appear to function more like a standard ED driven by specialized health care.Peer reviewe

    Maternal asthma is associated with increased risk of perinatal mortality

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    Background Asthma is the most common chronic disease during pregnancy and it may have influence on pregnancy outcome. Objectives Our goal was to assess the association between maternal asthma and the perinatal risks as well as possible effects of asthma medication. Methods The study was based on a nationwide Finnish register-based cohort between the years 1996 and 2012 in the Drug and Pregnancy Database. The register data comprised 962 405 singleton live and stillbirths, 898 333 (93.3%) pregnancies in mothers with neither confirmed asthma nor use of asthma medication (controls), and 26 674 (2.8%) pregnancies with confirmed maternal asthma. 71% of mothers with asthma used asthma medication. The diagnosis of asthma was based on the mothers' right for subsidised medication which is carefully evaluated by strict criteria including pulmonary function testing. Odds ratio was used in comparison. Premature birth (PB), low birth weight, small for gestational age (SGA), neonatal death were the main outcome measures. Results Maternal asthma was associated with adjusted odds ratios (aORs) for perinatal mortality 1.24 (95% CI 1.05 to 1.46), preterm birth 1.18 (1.11 to 1.25), low birth weight 1.29 (1.21 to 1.37), fetal growth restriction (SGA) 1.32, (1.24 to 1.40), and asphyxia 1.09 (1.02 to 1.17). Asthma treatment reduced the increased risk of preterm birth aOR 0.85 (95% CI 0.76 to 0.96) but mothers with treated asthma had higher risks of fetal growth restriction (SGA) aOR 1.26 (1.10 to 1.45), and asphyxia aOR 1.37 (1.17 to 1.61) than mothers with untreated asthma. Conclusion Asthma is associated with increased risks of perinatal mortality, preterm birth, low birth weight, fetal growth restriction (SGA), and asphyxia. Asthma treatment reduces the risk of preterm delivery, but it does not seem to reduce other complications such as perinatal mortality.Peer reviewe

    Vitamin D, high-sensitivity C-reactive protein, and airway hyperresponsiveness in infants with recurrent respiratory symptoms

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    Background: Vitamin D insufficiency might be associated with biased T-cell responses resulting in inflammatory conditions such as atopy and asthma. Little is known about the role of vitamin D in low-grade systemic inflammation and airway hyperresponsiveness (AHR) in young children. Objective: To evaluate whether vitamin D insufficiency and increased serum high-sensitivity C-reactive protein (hs-CRP) are linked to AHR in symptomatic infants. Methods: Seventy-nine infants with recurrent or persistent lower respiratory tract symptoms underwent comprehensive lung function testing and a bronchial methacholine challenge test. In addition, skin prick tests were performed and serum 25-hydroxyvitamin D (S-25-OHD), hs-CRP, total immunoglobulin E, and blood eosinophil levels were determined. Results: S-25-OHD was lowest in infants with blood eosinophilia and AHR (n = 10) compared with those with eosinophilia only (n = 6) or AHR only (n = 50) or those with neither (n = 13; P = .035). Moreover, vitamin D insufficiency (S-25-OHD <50 nmol/L) was most common in infants with blood eosinophilia and AHR (P = .041). Serum hs-CRP was lower in infants with recurrent physician-diagnosed wheezing (P = .048) and in those with blood eosinophilia (P = .015) than in infants without these characteristics and was not associated with S-25-OHD or AHR. S-25-OHD levels were significantly lower (median 54 nmol/L) during the autumn-winter season than in the spring-summer season (median 63 nmol/L; P = .026). Conclusion: Vitamin D insufficiency could underlie eosinophilia and AHR in infants with troublesome lung symptoms, whereas hs-CRPemediated low-grade systemic inflammation is rare in early childhood wheezing. (C) 2017 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.Peer reviewe

    Sublingual administration of detomidine to calves prior to disbudding: a comparison with the intravenous route.

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    Objective: To study the effects of oromucosal detomidine gel administered sublingually to calves prior to disbudding, and to compare its efficacy with intravenously administered detomidine. Study design: Randomised, prospective clinical study. Animals: Twenty dairy calves aged 12.4 ± 4.4 days (mean ± SD), weight 50.5 ± 9.0 kg. Methods: Detomidine at 80 μg kg-1 was administered to ten calves sublingually (GEL) and at 30 μg kg-1 to ten control calves intravenously (IV). Meloxicam (0.5 mg kg-1) and  local anaesthetic (lidocaine 3 mg kg-1) were administered before heat cauterization of horn buds. Heart rate (HR), body temperature and clinical sedation were monitored over  240 minutes. Blood was collected during the same period for drug concentration  analysis. Pharmacokinetic variables were calculated from the plasma detomidine  concentration-time data using non-compartmental methods.  Results: The maximum plasma detomidine concentration after GEL was 2.1 ± 1.2 ng  mL-1 (mean ± SD) and the time of maximum concentration was 66.0 ± 36.9 minutes. The bioavailability of detomidine was approximately 34% with GEL. Similar sedation  scores were reached in both groups after administration of detomidine, but maximal sedation was reached earlier in the IV group (10 minutes) than in the GEL group (40 minutes). HR was lower after IV than GEL from 5 to 10 minutes after administration. All animals were adequately sedated, and we were able to administer local anaesthetic without resistance to all of the calves before disbudding. Conclusions and clinical relevance: Oromucosally administered detomidine is an  effective sedative agent for calves prior to disbudding.Peer reviewe
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