bluuebunny/crossref_metadata_2025_split huggingface dataset:
A decline in primary production in the North Sea over 25 years, associated with reductions in zooplankton abundance and fish stock recruitment
Authors: Capuzzo Elisa , Lynam Christopher P. , Barry Jon , Stephens David , Forster Rodney M. , Greenwood Naomi , McQuatters‐Gollop Abigail , Silva Tiago , van Leeuwen Sonja M. , Engelhard Georg H. 
Published: September 2017

AbstractPhytoplankton primary production is at the base of the marine food web; changes in primary production have direct or indirect effects on higher trophic levels, from zooplankton organisms to marine mammals and seabirds. Here, we present a new time‐series on gross primary production in the North Sea, from 1988 to 2013, estimated using in situ measurements of chlorophyll and underwater light. This shows that recent decades have seen a significant decline in primary production in the North Sea. Moreover, primary production differs in magnitude between six hydrodynamic regions within the North Sea. Sea surface warming and reduced riverine nutrient inputs are found to be likely contributors to the declining levels of primary production. In turn, significant correlations are found between observed changes in primary production and the dynamics of higher trophic levels including (small) copepods and a standardized index of fish recruitment, averaged over seven stocks of high commercial significance in the North Sea. Given positive (bottom‐up) associations between primary production, zooplankton abundance and fish stock recruitment, this study provides strong evidence that if the decline in primary production continues, knock‐on effects upon the productivity of fisheries are to be expected unless these fisheries are managed effectively and cautiously.
Interannual variability of ecosystem carbon exchange: From observation to prediction
Authors: Niu Shuli , Fu Zheng , Luo Yiqi , Stoy Paul C. , Keenan Trevor F. , Poulter Benjamin , Zhang Leiming , Piao Shilong , Zhou Xuhui , Zheng Han , Han Jiayin , Wang Qiufeng , Yu Guirui 
Published: September 2017

AbstractAimTerrestrial ecosystems have sequestered, on average, the equivalent of 30% of anthropogenic carbon (C) emissions during the past decades, but annual sequestration varies from year to year. For effective C management, it is imperative to develop a predictive understanding of the interannual variability (IAV) of terrestrial net ecosystem C exchange (NEE).LocationGlobal terrestrial ecosystems.MethodsWe conducted a comprehensive review to examine the IAV of NEE at global, regional and ecosystem scales. Then we outlined a conceptual framework for understanding how anomalies in climate factors impact ecological processes of C cycling and thus influence the IAV of NEE through biogeochemical regulation.ResultsThe phenomenon of IAV in land NEE has been ubiquitously observed at global, regional and ecosystem scales. Global IAV is often attributable to either tropical or semi‐arid regions, or to some combination thereof, which is still under debate. Previous studies focus on identifying climate factors as driving forces of IAV, whereas biological mechanisms underlying the IAV of ecosystem NEE are less clear. We found that climate anomalies affect the IAV of NEE primarily through their differential impacts on ecosystem C uptake and respiration. Moreover, recent studies suggest that the carbon uptake period makes less contribution than the carbon uptake amplitude to IAV in NEE. Although land models incorporate most processes underlying IAV, their efficacy to predict the IAV in NEE remains low.Main conclusionsTo improve our ability to predict future IAV of the terrestrial C cycle, we have to understand biological mechanisms through which anomalies in climate factors cause the IAV of NEE. Future research needs to pay more attention not only to the differential effects of climate anomalies on photosynthesis and respiration but also to the relative importance of the C uptake period and amplitude in causing the IAV of NEE. Ultimately, we need multiple independent approaches, such as benchmark analysis, data assimilation and time‐series statistics, to integrate data, modelling frameworks and theory to improve our ability to predict future IAV in the terrestrial C cycle.
Biome‐specific climatic space defined by temperature and precipitation predictability
Authors: Jiang Mingkai , Felzer Benjamin S. , Nielsen Uffe N. , Medlyn Belinda E. 
Published: September 2017

AbstractAimGlobal biomes are often classified by mean annual temperature and precipitation, but there is significant overlap between biomes, making it difficult to interpret the role of climate in the distribution of biomes globally. Climate predictability (including long‐term reliability of both seasonality and inter‐annual variability) varies considerably between biomes and regulates biodiversity distribution, adaptation and evolution, but its global pattern has rarely been investigated. The aim of this study was to characterize climatic space quantitatively for major biomes of the world using temperature and precipitation predictability, and to interpret its biological implications under future climate change.LocationGlobal.Time Period1901–2012.MethodsWe calculated global gridded temperature and precipitation predictability based on an information theory approach, and compared climatic spaces defined by these measures within and across biomes.ResultsWe show that temperature predictability has a clear latitudinal gradient, whereas precipitation predictability is geographically variable. We further show that temperature and precipitation predictability form distinct climatic spaces for major biomes across the globe, and importantly, temperature and precipitation predictability can robustly distinguish biomes that are overlapping in mean annual climate statistics.Main conclusionsClimatic space created by temperature and precipitation predictability supplements the traditional biome‐specific climatic spaces created by annual mean temperature and total precipitation. Quantifying measures of climate predictability helps us to understand adaptation strategies adopted by local organisms within and across biomes. Our results show that quantifying climate predictability is a simple and effective way to delineate more robustly biome climate space and its influences on macroecology and evolutionary biology, which in turn could underpin conservation efforts under future climate change, especially when prevailing climates are comparable in terms of magnitude.
Dentition status and frailty in community‐dwelling older adults: A 5‐year prospective cohort study
Authors: Iwasaki Masanori , Yoshihara Akihiro , Sato Misuzu , Minagawa Kumiko , Shimada Mieko , Nishimuta Mamoru , Ansai Toshihiro , Yoshitake Yutaka , Miyazaki Hideo 
Published: September 2017

AimTo examine the longitudinal association between dentition status and incidence of frailty in older adults.MethodsThe present prospective cohort study included community‐dwelling Japanese adults aged 75 years at baseline (n = 322). Dental examinations, biochemical blood examinations, physical performance and anthropometric measurements, and structured questionnaires were carried out at baseline. The presence of ≥20 teeth with nine or more occluding pairs of teeth was defined as functional dentition. Annual follow‐up examinations, including physical performance, anthropometric measurements and structured questionnaires, were carried out over a 5‐year period to determine the incidence of frailty, defined as three or more of the following five components derived from the Cardiovascular Health Study: weight loss, weakness, slowness, poor energy and low physical activity level. Adjusted hazard ratios of frailty incidence according to dentition status were calculated from Cox proportional hazards regression analyses.ResultsAt baseline, 118 participants (36.6%) were defined as having functional dentition. During the follow up, 48 participants (14.9%) developed frailty. The adjusted hazard ratio for frailty in participants with functional dentition was 0.50 (95% confidence interval 0.25–0.98) compared with participants without functional dentition, after adjusting for sex, income, education, smoking status, body mass index, serum biomarkers and comorbidities.ConclusionsFunctional dentition was significantly associated with a lower risk of frailty defined by the Cardiovascular Health Study frailty index in older Japanese adults. These results suggest that maintaining healthy and functional dentition into later life is important for frailty prevention. Geriatr Gerontol Int 2018; 18: 256–262.
Ginsenoside Rb1 enhances atherosclerotic plaque stability by skewing macrophages to the M2 phenotype
Authors: Zhang Xue , Liu Ming‐hao , Qiao Lei , Zhang Xin‐yu , Liu Xiao‐ling , Dong Mei , Dai Hong‐yan , Ni Mei , Luan Xiao‐rong , Guan Jun , Lu Hui‐xia 
Published: September 2017

AbstractAtherosclerosis (AS) is characterized as progressive arterial plaque, which is easy to rupture under low stability. Macrophage polarization and inflammation response plays an important role in regulating plaque stability. Ginsenoside Rb1 (Rb1), one of the main active principles of Panax Ginseng, has been found powerful potential in alleviating inflammatory response. However, whether Rb1 could exert protective effects on AS plaque stability remains unclear. This study investigated the role of Rb1 on macrophage polarization and atherosclerotic plaque stability using primary peritoneal macrophages isolated from C57BL/6 mice and AS model in ApoE−/− mice. In vitro, Rb1 treatment promoted the expression of arginase‐I (Arg‐I) and macrophage mannose receptor (CD206), two classic M2 macrophages markers, while the expression of iNOS (M1 macrophages) was decreased. Rb1 increased interleukin‐4 (IL‐4) and interleukin‐13 (IL‐13) secretion in supernatant and promoted STAT6 phosphorylation. IL‐4 and/or IL‐13 neutralizing antibodies and leflunomide, a STAT6 inhibitor attenuated the up‐regulation of M2 markers induced by Rb1. In vivo, the administration of Rb1 promoted atherosclerotic lesion stability, accompanied by increased M2 macrophage phenotype and reduced MMP‐9 staining. These data suggested that Rb1 enhanced atherosclerotic plaque stability through promoting anti‐inflammatory M2 macrophage polarization, which is achieved partly by increasing the production of IL‐4 and/or IL‐13 and STAT6 phosphorylation. Our study provides new evidence for possibility of Rb1 in prevention and treatment of atherosclerosis.
Systemic redistribution of the intramyocardially injected mesenchymal stem cells by repeated remote ischaemic post‐conditioning
Authors: Jiang Qin , Yu Tao , Huang Keli , Zhang Hao , Zheng Zhe , Hu Shengshou 
Published: September 2017

AbstractWe investigated the effect of repeated remote ischaemic post‐conditioning (RIPoC) on the organ distribution of the intramyocardially injected MSCs in rat myocardial ischemia model. Myocardial ischemia of adult female Sprague‐Dawley rats was induced by 30‐min. obstruction of the left anterior descending coronary artery. Repeated RIPoC was induced after ischemia with three cycles of 5‐min. occlusion and reperfusion of the limb with the frequency of half a day, 1 or 2 days, respectively. Compared with that by single RIPoC, repeated RIPoC transiently reduced oxidative stress, lipid peroxidation and inflammation in ischaemic myocardium; the gene expression of stromal cell‐derived factor‐1 alpha (SDF‐1α) was consistently induced by repeated RIPoC procedures. A total of 4 × 106 male bone marrow‐derived MSCs were intramyocardially injected into ischaemic myocardium at 1 week after reperfusion. Three weeks later, immunohistological examination and quantitative reverse transcriptase polymerase chain reaction demonstrated that repeated RIPoC significantly increased MSCs retention in myocardium and decreased MSCs distribution over the lungs, spleen and liver; echocardiography assessment revealed that further cardiac function enhancement imposed by repeated RIPoC procedure. Furthermore, blockade with the anti‐CXCR4 antibody before cell transplantation markedly attenuated the benefits of therapeutic efficacy and cardiac function. Repeated RIPoC enhanced MSCs engraftment in ischaemic myocardium and reduced the distribution of MSCs over peripheral organs in a frequency‐effect way, but it reached a ceiling of maximal effect when applied with every 1 day. The SDF1α‐CXCR4 interaction played a major role in MSCs systemic redistribution induced by repeated RIPoC.
Effect of repeated exposure to AQUI‐S® on the viability and growth of Neoparamoeba perurans
Authors: Chance R J , Allcock Z , Secombes C J , Collet B , Collins C 
Published: September 2017

AbstractThere have been recent efforts amongst immunologists to develop approaches for following individual fish during challenges with viral and bacterial pathogens. This study contributes to assessing the feasibility of using such approaches to study amoebic gill disease (AGD). Neoparamoeba perurans, agent of AGD, has been responsible for widespread economic and fish loss in salmonid aquaculture. With the emergence of AGD in Europe, research into infection dynamics and host response has increased. This study investigated the effect of repeat exposure to anaesthesia, a necessary requirement when following disease progression in individual fish, on N. perurans. In vitro cultures of N. perurans were exposed every 4 days over a 28‐day period to AQUI‐S® (isoeugenol), a popular anaesthetic choice for AGD challenges, at a concentration and duration required to sedate post‐smolt salmonids. Population growth was measured by sequential counts of amoeba over the period, while viability of non‐attached amoeba in the culture was assessed with a vital stain. AQUI‐S® was found to be a suitable choice for in vivo ectoparasitic challenges with N. perurans during which repetitive anaesthesia is required for analysis of disease progression.
Autoantibodies against aldehyde‐modified collagen type IV are associated with risk of development of myocardial infarction
Authors: Vallejo J. , Dunér P. , Fredrikson G. N. , Nilsson J. , Bengtsson E. 
Published: September 2017

AbstractBackgroundOxidation of LDL particles entrapped in the extracellular matrix of the arterial wall is a key factor in the development of atherosclerosis. Lipid oxidation products, such as malondialdehyde (MDA), react with surrounding extracellular matrix proteins and cause modifications that are recognized by the immune system. MDA modification of collagen type IV is increased in carotid lesions from symptomatic patients and correlates with autoantibodies against MDA‐modified collagen type IV in plasma.ObjectiveThe aim of this study was to determine whether autoantibodies against MDA‐modified collagen type IV predict risk of development of myocardial infarction (MI).MethodsPlasma levels of MDA‐modified collagen type IV IgM and IgG antibodies were analysed by enzyme‐linked immunosorbent assay in 385 subjects with incident MI during 13 years of follow‐up and 410 age‐ and sex‐matched controls in the Malmö Diet and Cancer study.ResultsMDA‐modified collagen type IV IgG levels were higher in cases with incident MI than in controls. Subjects in the highest tertile of MDA‐modified collagen type IV IgG had an increased risk of MI (hazard ratio 1.56, 95% confidence interval 1.22–2.00, P for trend 0.0004). This association remained significant after adjusting for factors included in the Framingham risk score and diabetes. High levels of MDA‐collagen type IV IgG were associated with increased carotid intima‐media thickness and elevated plasma levels of matrix metalloproteinase 10 and 12.ConclusionsImmune responses against MDA‐modified collagen type IV are associated with more severe carotid disease and increased risk of MI. These immune responses may reflect LDL oxidation in the artery wall, but could also affect the atherosclerotic disease process.
Changes of vitamin D levels and bone turnover markers after CPAP therapy: a randomized sham‐controlled trial
Authors: Theorell‐Haglöw Jenny , Hoyos Camilla M. , Phillips Craig L. , Yee Brendon J. , Herrmann Markus , Brennan‐Speranza Tara C. , Grunstein Ronald R. , Liu Peter Y. 
Published: September 2017

SummaryThe aim was to investigate whether continuous positive airway pressure treatment could modulate serum vitamin D (25‐hydroxyvitamin D) and bone turnover markers (collagen‐type 1 cross‐linked C‐telopeptide, osteocalcin and N‐terminal propeptide of type 1 collagen) in secondary analysis from a randomized controlled trial. Sixty‐five continuous positive airway pressure‐naïve male patients with obstructive sleep apnea (age = 49 ± 12 years, apnea–hypopnea index = 39.9 ± 17.7 events h−1, body mass index = 31.3 ± 5.2 kg m−2) were randomized to receive either real (n = 34) or sham (n = 31) continuous positive airway pressure for 12 weeks. At 12 weeks, all participants received real continuous positive airway pressure for an additional 12 weeks. After 12 weeks of continuous positive airway pressure (real versus sham), there were no between‐group differences for any of the main outcomes [Δ25‐hydroxyvitamin D: −0.80 ± 5.28 ng mL−1 (mean ± SE) versus 3.08 ± 3.66 ng mL−1, P = 0.42; Δcollagen‐type 1 cross‐linked C‐telopeptide: 0.011 ± 0.014 ng mL−1 versus −0.004 ± 0.009 ng mL−1, P = 0.48; Δosteocalcin: 1.13 ± 1.12 ng mL−1 versus 0.46 ± 0.75 ng mL−1, P = 0.80; ΔN‐terminal propeptide of type 1 collagen: 2.07 ± 3.05 μg L−1 versus −1.05 ± 2.13 μg L−1, P = 0.48]. There were no further differences in subgroup analyses (continuous positive airway pressure‐compliant patients, patients with severe obstructive sleep apnea or sleepy patients). However, after 24 weeks irrespective of initial randomization, vitamin D increased in patients with severe obstructive sleep apnea (9.56 ± 5.51 ng mL−1, P = 0.045) and in sleepy patients (14.0 ± 4.69 ng mL−1, P = 0.007). Also, there was a significant increase in osteocalcin at 24 weeks (3.27 ± 1.06 ng mL−1, P = 0.01) in compliant patients. We conclude that 12 weeks of continuous positive airway pressure did not modulate vitamin D or modulate any of the bone turnover markers compared with sham. However, it is plausible that continuous positive airway pressure may have late beneficial effects on vitamin D levels and bone turnover markers in selected groups of patients with obstructive sleep apnea.
A comparison of two screening tools for paediatric obstructive sleep apnea
Authors: Abumuamar Asmaa M. , Chung Sharon A. , Kadmon Gili , Shapiro Colin M. 
Published: September 2017

SummaryUntreated obstructive sleep apnea in children is associated with significant medical and psychological morbidities. Polysomnographic testing is the gold‐standard method for diagnosis of obstructive sleep apnea. However, laboratory‐based polysomnography is expensive and associated with a substantial healthcare burden. Thus, a simple valid tool to accurately identify those at high risk of obstructive sleep apnea is essential. We performed a retrospective cross‐sectional study of children referred to the Youthdale Child and Adolescent Sleep Clinic. Data were collected from questionnaires and sleep studies reports of 395 children. A comparison between two screening tools for paediatric obstructive sleep apnea – a six‐item (parent‐response) and an eight‐item IF‐SLEEPY/IM‐SLEEPY scales – was performed. The results showed that 42% of the children (n = 164) were diagnosed with obstructive sleep apnea. The six‐item scale (score ≥3) exhibited a sensitivity of 17% and a specificity of 95% for diagnosing obstructive sleep apnea. The eight‐item IF‐SLEEPY scale displayed 82% sensitivity and 28% specificity. The IM‐SLEEPY scale exhibited 79% sensitivity and 32% specificity. In children ≥7 years old, the IF‐SLEEPY (parent‐response) had a sensitivity of 82% and specificity of 28% compared with the child‐response (66% and 37%, respectively). Logistic regression analysis revealed that age (odds ratio = 0.78), IF‐SLEEPY/IM‐SLEEPY score ≥3 (odds ratio = 1.78) and a score ≥2.72 on the six‐item scale (odds ratio = 4.54) were predictors of obstructive sleep apnea. This study suggests that the eight‐item scale is a better screening tool for paediatric obstructive sleep apnea, with a higher sensitivity and simple yes/no responses that are easy to complete and to score.
Child Custody and Family Labour Supply: Evidence from the United States
Authors: Nguyen Dung Kieu , Tran Thi Van Anh , Phan Trang 
Published: September 2017

AbstractThis paper investigates the impact of the joint child custody reforms on family labour supply in the United States between the 1970s and 1990s. Following the work of Chiappori et al. (Journal of Political Economy, 2002, 110 (1): 37–72), we propose a collective labour supply model in which the custody reforms play roles of a distribution factor that influences household bargaining power. In the empirical section, using data from the March Current Population Survey and Panel Study of Income Dynamics, we find a significantly positive influence of the legality on married women's labour supply and a negative influence on their husbands’. Checking robustness with different groups: non‐migrant couples, couples with children under 18, couples with children before the passage of the laws, couples married before the reforms and couples with non‐anti‐divorce religious preference, we find the results are consistent with those of the baseline model.
Effects of habitat complexity on cannibalism rates in European green crabs (Carcinus maenas Linnaeus, 1758)
Authors: Gehrels Hannah , Tummon Flynn Paula , Cox Ruth , Quijón Pedro A. 
Published: September 2017

AbstractThe habitat in which predator–prey interactions take place may have a profound influence on the outcome of those interactions. Cannibalism is an intriguing form of predation whereby foraging by predators may contribute to the regulation of their own populations.This is particularly interesting in the case of invasive species, like the widely distributed European green crab (Carcinus maenas). This study explores how habitat complexity influences cannibalism rates in green crab populations of Prince Edward Island, Atlantic Canada. Both laboratory and field experiments were conducted to measure feeding rates by individual adult green crabs on a standard number of smaller conspecifics. In the laboratory, experimental treatments mimicked unstructured to increasingly structured habitats: water, sandy bottom, oyster shells, mussel shells, oyster shells with sandy bottom and mussel shells with sandy bottom. In those trials, adult green crabs consumed several times more juveniles on unstructured habitats than on the most structured ones, with a gradual decrease in predation rates across increasingly complex habitats. Field inclusion experiments used the same approach and were conducted in sandy bottoms, sandy bottoms with a layer of oyster shells and sandy bottoms with a layer of mussel shells. These trials showed similar patterns of decreasing feeding rates across increasingly complex habitats, but differences among treatments were not significant. These results support the idea that complex habitats have the potential to mediate predator–prey interactions, including adult–juvenile cannibalism in green crabs.