87 research outputs found

    Limits of effective nutrient management in dairy farming: analyses of experimental farm De Marke

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    Key words: nutrient management, dairy, prototyping, organic matter, soil fertility, nitrogen, phosphor. Intensive dairy production in the Netherlands is associated with high farm nutrient (N and P) inputs and high losses to the environment. The Dutch government and the dairy sector stimulate farmers to reduce losses through more efficient use of N and P inputs on their farms. This study explores for a dairy farm on dry sandy soil with average Dutch production intensity (12,000 kg milk per ha) the possibilities to meet strict environmental standards related to N and P by maximizing N and P use efficiency at the level of the farm and of the soil. Moreover, the study addresses the effects of efficient nutrient management on soil fertility. The research was conducted on experimental dairy farm De Marke, that is designed to meet strict environmental standards, implemented in practice in 1989 and modified continuously to meet its targets by prototyping, i.e. a cyclic procedure of designing, implementing, testing and evaluating measures. The thesis evaluates system development since 2000, while results from 1993-1999 were used to analyse long-term developments. After implementation of the farming system in 1989, the nitrate concentration in groundwater ‘stabilized’ at a level exceeding the environmental standard: 55 mg l-1. Causes of excessive nitrate leaching were examined by relating measured nitrate concentrations to management. Grazing was associated with higher leaching in spite of careful management with rotational grazing. Leaching under permanent grassland was similar to the overall leaching in crop rotations in which grass was alternated with maize and grains. Spatial and temporal patterns of soil N mineralization were explored to improve the synchronization of N application and crop N requirements. This study indicated that fertilizing a 1st year maize crop, following grassland, is not necessary. Measures implemented since 2000 to improve nutrient efficiency, included reduced grazing, adoption of anaerobic digestion, application of manure in the rows of maize, growing spring barley as the last crop in the arable phase, and, since 2004, the abolishment of fertilizer N. These measures contributed to an increase in the manure-N utilization and to an increase in the farm-N use efficiency up to 2008 to values exceeding the value of 33% that was realized in the period 1993-1999. Farm-N use efficiency was 35% in 2000-2003, 43% in 2004-2008 and 37% in 2009-2010. Farm-P use efficiency also increased as compared to the 87% that was realized in 1993-1999, i.e., it was 103% in 2000-2003 and 91% in 2004-2008. In 2009-2010, however, the farm-P use efficiency decreased to 69%, lower than the value realized in 1993-1999. The lower N and P use efficiency in 2009-2010 can be attributed to the lower N and P yields in grassland as a delayed effect of N limitation resulting from the abolishment of fertilizer N in grassland since 2004. Hence, despite the increase in manure-N utilization, mineral-N use is not yet completely redundant. P-equilibrium fertilization seems to be compatible with highly efficient crop production, in the short and in the long term. Soil organic matter (SOM) percentage in the upper topsoil decreased by 0.03 yr-1 (average across all land uses) at a constant rate over the last 20 years. The possibilities to stop this decline by higher organic matter inputs to the soil seem conflicting with efficient nutrient use. Hence, the long term dynamics of SOM may become critical for future farm performance. It was concluded that N and P use efficiency can be enhanced substantially by on-farm nutrient management, but that efficient nutrient management may conflict with maintenance of SOM.</p

    TLR4 Asp299Gly and Thr399Ile Polymorphisms: No Impact on Human Immune Responsiveness to LPS or Respiratory Syncytial Virus

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    A broad variety of natural environmental stimuli, genotypic influences and timing all contribute to expression of protective versus maladaptive immune responses and the resulting clinical outcomes in humans. The role of commonly co-segregating Toll-like receptor 4 (TLR4) non-synonymous single nucleotide polymorphisms Asp299Gly and Thr399Ile in this process remains highly controversial. Moreover, what differential impact these polymorphisms might have in at risk populations with respiratory dysfunction, such as current asthma or a history of infantile bronchiolitis, has never been examined. Here we determine the importance of these polymorphisms in modulating LPS and respiratory syncytial virus (RSV)--driven cytokine responses. We focus on both healthy children and those with clinically relevant respiratory dysfunction.To elucidate the impact of TLR4 Asp299Gly and Thr399Ile on cytokine production, we assessed multiple immune parameters in over 200 pediatric subjects aged 7-9. Genotyping was followed by quantification of pro- and anti-inflammatory cytokine responses by fresh peripheral blood mononuclear cells upon acute exposure to LPS or RSV.In contrast to early reports, neither SNP influenced immune responses evoked by LPS exposure or RSV infection, as measured by the intermediate phenotype of pro- and anti-inflammatory cytokine responses to these ubiquitous agents. There is no evidence of altered sensitivity in populations with "at risk" clinical phenotypes.Genomic medicine seeks to inform clinical practice. Determination of the TLR4 Asp299Gly/Thr399Ile haplotype is of no clinical benefit in predicting the nature or intensity of cytokine production in children whether currently healthy or among specific at-risk groups characterized by prior infantile broncholitis or current asthma

    Nematic pairing from orbital-selective spin fluctuations in FeSe

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    FeSe is an intriguing iron-based superconductor. It presents an unusual nematic state without magnetism and can be tuned to increase the critical superconducting temperature. Recently it has been observed a noteworthy anisotropy of the superconducting gaps. Its explanation is intimately related to the understanding of the nematic transition itself. Here, we show that the spin-nematic scenario driven by orbital-selective spin fluctuations provides a simple scheme to understand both phenomena. The pairing mediated by anisotropic spin modes is not only orbital selective but also nematic, leading to stronger pair scattering across the hole and X electron pocket. The delicate balance between orbital ordering and nematic pairing points also to a marked k z dependence of the hole\u2013gap anisotropy

    Inflammasome-Mediated IL-1β Production in Humans with Cystic Fibrosis

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    Inflammation and infection are major determinants of disease severity and consequently, the quality of life and outcome for patients with cystic fibrosis (CF). Interleukin-1 beta (IL-1β) is a key inflammatory mediator. Secretion of biologically active IL-1β involves inflammasome-mediated processing. Little is known about the contribution of IL-1β and the inflammasomes in CF inflammatory disease. This study examines inflammasome-mediated IL-1β production in CF bronchial epithelial cell lines and human patients with CF.Bronchial epithelial cell lines were found to produce negligible amounts of basal or stimulated IL-1β compared to hematopoeitic cells and they did not significantly upregulate caspase-1 activity upon inflammasome stimulation. In contrast, peripheral blood mononuclear cells (PBMCs) from both CF and healthy control subjects produced large amounts of IL-1β and strongly upregulated caspase-1 activity upon inflammasome stimulation. PBMCs from CF patients and controls displayed similar levels of caspase-1 activation and IL-1β production when stimulated with inflammasome activators. This IL-1β production was dependent on NF-κB activity and could be enhanced by priming with LPS. Finally, chemical inhibition of CFTR activity in control PBMCs and THP-1 cells did not significantly alter IL-1β or IL-8 production in response to P. aeruginosa.Hematopoeitic cells appear to be the predominant source of inflammasome-induced pro-inflammatory IL-1β in CF. PBMCs derived from CF subjects display preserved inflammasome activation and IL-1β secretion in response to the major CF pathogen Pseudomonas aeruginosa. However, our data do not support the hypothesis that increased IL-1β production in CF subjects is due to an intrinsic increase in NF-κB activity through loss of CFTR function

    Spent Culture Medium from Virulent Borrelia burgdorferi Increases Permeability of Individually Perfused Microvessels of Rat Mesentery

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    Lyme disease is a common vector-borne disease caused by the spirochete Borrelia burgdorferi (Bb), which manifests as systemic and targeted tissue inflammation. Both in vitro and in vivo studies have shown that Bb-induced inflammation is primarily host-mediated, via cytokine or chemokine production that promotes leukocyte adhesion/migration. Whether Bb produces mediators that can directly alter the vascular permeability in vivo has not been investigated. The objective of the present study was to investigate if Bb produces a mediator(s) that can directly activate endothelial cells resulting in increases in permeability in intact microvessels in the absence of blood cells.The effects of cell-free, spent culture medium from virulent (B31-A3) and avirulent (B31-A) B. burgdorferi on microvessel permeability and endothelial calcium concentration, [Ca(2+)](i), were examined in individually perfused rat mesenteric venules. Microvessel permeability was determined by measuring hydraulic conductivity (Lp). Endothelial [Ca(2+)](i), a necessary signal initiating hyperpermeability, was measured in Fura-2 loaded microvessels. B31-A3 spent medium caused a rapid and transient increase in Lp and endothelial [Ca(2+)](i). Within 2-5 min, the mean peak Lp increased to 5.6+/-0.9 times the control, and endothelial [Ca(2+)](i) increased from 113+/-11 nM to a mean peak value of 324+/-35 nM. In contrast, neither endothelial [Ca(2+)](i) nor Lp was altered by B31-A spent medium.A mediator(s) produced by virulent Bb under culture conditions directly activates endothelial cells, resulting in increases in microvessel permeability. Most importantly, the production of this mediator is associated with Bb virulence and is likely produced by one or more of the 8 plasmid(s) missing from strain B31-A

    Treatment of chronically depressed patients: A multisite randomized controlled trial testing the effectiveness of 'Cognitive Behavioral Analysis System of Psychotherapy' (CBASP) for chronic depressions versus usual secondary care

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    AbstractBackground'Cognitive Behavioral Analysis System of Psychotherapy' (CBASP) is a form of psychotherapy specifically developed for patients with chronic depression. In a study in the U.S., remarkable favorable effects of CBASP have been demonstrated. However, no other studies have as yet replicated these findings and CBASP has not been tested outside the United States. This protocol describes a randomized controlled trial on the effectiveness of CBASP in the Netherlands.Methods/DesignThe purpose of the present paper is to report the study protocol of a multisite randomized controlled trial testing the effectiveness of 'Cognitive Behavioral Analysis System of Psychotherapy' (CBASP) for chronic depression in the Netherlands. In this study, CBASP in combination with medication, will be tested versus usual secondary care in combination with medication. The aim is to recruit 160 patients from three mental health care organizations. Depressive symptoms will be assessed at baseline, after 8 weeks, 16 weeks, 32 weeks and 52 weeks, using the 28-item Inventory for Depressive Symptomatology (IDS). Effect modification by co morbid anxiety, alcohol consumption, general and social functioning and working alliance will be tested. GEE analyses of covariance, controlling for baseline value and center will be used to estimate the overall treatment effectiveness (difference in IDS score) at post-treatment and follow up. The primary analysis will be by 'intention to treat' using double sided tests. An economic analysis will compare the two groups in terms of mean costs and cost-effectiveness from a societal perspective.DiscussionThe study will provide an answer to the question whether the favorable effects of CBASP can be replicated outside the US

    A Genome-Wide Association Study of Neuroticism in a Population-Based Sample

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    Neuroticism is a moderately heritable personality trait considered to be a risk factor for developing major depression, anxiety disorders and dementia. We performed a genome-wide association study in 2,235 participants drawn from a population-based study of neuroticism, making this the largest association study for neuroticism to date. Neuroticism was measured by the Eysenck Personality Questionnaire. After Quality Control, we analysed 430,000 autosomal SNPs together with an additional 1.2 million SNPs imputed with high quality from the Hap Map CEU samples. We found a very small effect of population stratification, corrected using one principal component, and some cryptic kinship that required no correction. NKAIN2 showed suggestive evidence of association with neuroticism as a main effect (p<10−6) and GPC6 showed suggestive evidence for interaction with age (p≈10−7). We found support for one previously-reported association (PDE4D), but failed to replicate other recent reports. These results suggest common SNP variation does not strongly influence neuroticism. Our study was powered to detect almost all SNPs explaining at least 2% of heritability, and so our results effectively exclude the existence of loci having a major effect on neuroticism

    Human Integrin α3β1 Regulates TLR2 Recognition of Lipopeptides from Endosomal Compartments

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    Toll-like receptor (TLR)-2/TLR1 heterodimers recognize bacterial lipopeptides and initiate the production of inflammatory mediators. Adaptors and co-receptors that mediate this process, as well as the mechanisms by which these adaptors and co-receptors function, are still being discovered.Using shRNA, blocking antibodies, and fluorescent microscopy, we show that U937 macrophage responses to the TLR2/1 ligand, Pam(3)CSK(4), are dependent upon an integrin, α(3)β(1). The mechanism for integrin α(3)β(1) involvement in TLR2/1 signaling is through its role in endocytosis of lipopeptides. Using inhibitors of endosomal acidification/maturation and physical tethering of the ligand, we show that the endocytosis of Pam(3)CSK(4) is necessary for the complete TLR2/1-mediated pro-inflammatory cytokine response. We also show that TLR2/1 signaling from the endosome results in the induction of different inflammatory mediators than TLR2/1 signaling from the plasma membrane.Here we identify integrin α(3)β(1) as a novel regulator for the recognition of bacterial lipopeptides. We demonstrate that induction of a specific subset of cytokines is dependent upon integrin α(3)β(1)-mediated endocytosis of the ligand. In addition, we address an ongoing controversy regarding endosomal recognition of bacterial lipopeptides by demonstrating that TLR2/1 signals from within endosomal compartments as well as the plasma membrane, and that downstream responses may differ depending upon receptor localization. We propose that the regulation of endosomal TLR2/1 signaling by integrin α(3)β(1) serves as a mechanism for modulating inflammatory responses

    The development of compassionate engagement and action scales for self and others

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    Background Studies of the value of compassion on physical and mental health and social relationships have proliferated in the last 25 years. Although, there are several conceptualisations and measures of compassion, this study develops three new measures of compassion competencies derived from an evolutionary, motivational approach. The scales assess 1. the compassion we experience for others, 2. the compassion we experience from others, and 3. self-compassion based on a standard definition of compassion as a ‘sensitivity to suffering in self and others with a commitment to try to alleviate and prevent it’. We explored these in relationship to other compassion scales, self-criticism, depression, anxiety, stress and well-being. Methods Participants from three different countries (UK, Portugal and USA) completed a range of scales including compassion for others, self-compassion, self-criticism, shame, depression, anxiety and stress with the newly developed ‘The Compassionate Engagement and Actions’ scale. Results All three scales have good validity. Interestingly, we found that the three orientations of compassion are only moderately correlated to one another (r < .5). We also found that some elements of self-compassion (e.g., being sensitive to, and moved by one’s suffering) have a complex relationship with other attributes of compassion (e.g., empathy), and with depression, anxiety and stress. A path-analysis showed that self-compassion is a significant mediator of the association between self-reassurance and well-being, while self-criticism has a direct effect on depressive symptoms, not mediated by self-compassion. Discussion Compassion evolved from caring motivation and in humans is associated with a range of different socially intelligent competencies. Understanding how these competencies can be inhibited and facilitated is an important research endeavour. These new scales were designed to assess these competencies. Conclusions This is the first study to measure the three orientations of compassion derived from an evolutionary model of caring motivation with specified competencies. Our three new measures of compassion further indicate important complex relationships between different potentiation’s of compassion, well-being, and vulnerability to psychopathologies.N/
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