233 research outputs found

    ORGANIC FARMING IN DENMARK-PRODUCTIVITY, TECHNICAL CHANGE AND MARKET EXIT

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    This paper attempts to quantitatively measure the change in the productivity of Danish organic farming in recent years. Based on a translog production frontier framework the technical and scale efficiency on farm level is analysed by following a time trends as well as a general index model specification. We further try to analyse the significance of subsidies for promoting long term growth in organic production by estimating a bootstrapped bivariate probit model with respect to factors influencing the probability of organic market exit. The results revealed significant differencies in the organic farms' technical efficiencies, no significant total factor productivity growth and even a slightly negative rate of technical change in the period investigated. We found evidence for a positive relationship between subsidy payments and an increase in farm efficiency, technology improvements and a decreasing probability of organic market exit which was also confirmed for off farm income.Organic Farming, Total Factor Productivity, Market Exit, Agribusiness, Productivity Analysis,

    Relational Contracting and Allocation of Decision Rights in the Agri-Food Industry: Producer Contracts and Food Safety

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    We apply a formal theoretical model of adaptation to two empirical settings within the agri-food industry: specialized pig production and food safety in Denmark. The objective is to allocate decision rights ex ante so that actual decisions taken ex post will optimize the profit accruing to the two parties in a contractual or integrative relation. Two applications are presented in this paper: First an actual partnership between two pork producers in Denmark. Based on detailed budgets we develop detailed schedules for the “reneging temptations” of the two partners- These are the temptations to renege on the contract during the evolution of the partnership. Using a model developed by Baker, Gibbons and Murphy (2006) we calculate equilibria using the Folk theorem in order to determine which is the best allocation of decision rights. We find that the existing allocation of decision rights in the case we examine is efficient in the sense that it results into a second best allocation. Using the same modelling approach we present a second application on salmonella control related to end-feeding, that is, salmonella contamination of pork due to filled bellies of pigs fed for the last 12 hours before delivery. Based on appropriate assumptions, the parties should give the decision right (whether to end-feed or not) to the slaughterhouse in order to reach the firstbest solution which, given the assumptions, is feasibleTheory of the firm, Adaptation theory, Contracts, Decision Rights, Pig production, Food safety, Agribusiness, Agricultural and Food Policy, Farm Management, Food Consumption/Nutrition/Food Safety, Industrial Organization, D21, L2, Q1,

    Analysis of forensic DNA mixtures with artefacts

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    DNA is now routinely used in criminal investigations and court cases, although DNA samples taken at crime scenes are of varying quality and therefore present challenging problems for their interpretation. We present a statistical model for the quantitative peak information obtained from an electropherogram of a forensic DNA sample and illustrate its potential use for the analysis of criminal cases. In contrast with most previously used methods, we directly model the peak height information and incorporate important artefacts that are associated with the production of the electropherogram. Our model has a number of unknown parameters, and we show that these can be estimated by the method of maximum likelihood in the presence of multiple unknown individuals contributing to the sample, and their approximate standard errors calculated; the computations exploit a Bayesian network representation of the model. A case example from a UK trial, as reported in the literature, is used to illustrate the efficacy and use of the model, both in finding likelihood ratios to quantify the strength of evidence, and in the deconvolution of mixtures for finding likely profiles of the individuals contributing to the sample. Our model is readily extended to simultaneous analysis of more than one mixture as illustrated in a case example. We show that the combination of evidence from several samples may give an evidential strength which is close to that of a single-source trace and thus modelling of peak height information provides a potentially very efficient mixture analysis

    Estimation of Parameters in DNA Mixture Analysis

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    In Cowell et al. (2007), a Bayesian network for analysis of mixed traces of DNA was presented using gamma distributions for modelling peak sizes in the electropherogram. It was demonstrated that the analysis was sensitive to the choice of a variance factor and hence this should be adapted to any new trace analysed. In the present paper we discuss how the variance parameter can be estimated by maximum likelihood to achieve this. The unknown proportions of DNA from each contributor can similarly be estimated by maximum likelihood jointly with the variance parameter. Furthermore we discuss how to incorporate prior knowledge about the parameters in a Bayesian analysis. The proposed estimation methods are illustrated through a few examples of applications for calculating evidential value in casework and for mixture deconvolution

    Capturing of organic carbon and nitrogen in eelgrass sediments of southern Scandinavia

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    The ability of seagrass meadows to filter nutrients and capture and store CO2 and nutrients in the form of organic carbon (OC) and nitrogen (N) in their sediments may help to mitigate local eutrophication as well as climate change via meadow restoration and protection. This study assesses OC and N sediment stocks (top 50 cm) and sequestration rates within Danish eelgrass meadows. At four locations, eelgrass-vegetated and nearby unvegetated plots were studied in protected and exposed areas. The average OC and N sediment 50 cm stocks were 2.6 ± 0.3 kg OC m − 2 and 0.23 ± 0.01 kg N m − 2, including vegetated and unvegetated plots. In general, OC and N stocks did not differ significantly between eelgrass meadows and unvegetated sediments. Lack of accumulation of excess 210Pb suggested sediment erosion or low rates of sediment accumulation at most sites. OC accumulation rates ranged from 6 to 134 g m − 2 yr − 1 and N from 0.7 to 14 g m − 2 yr − 1. Generalized additive models showed that ≄ 80 % of the variation in sediment OC and N stocks was explained by sediment grain size, organic matter source, and hydrodynamic exposure. Long cores, dated with 210Pb, showed declining OC and N densities toward present time, suggesting long-term declines in eelgrass OC and N pools. Estimates of potential nation-wide OC and N accumulation in eelgrass sediments show that they could annually capture up to 0.7 % ± 0.5 % of CO2 emissions and 6.9 % ± 5.2 % of the total terrestrial N load

    Role of immunohistochemistry for interobserver agreement of Peritoneal Regression Grading Score in peritoneal metastasis.

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    Pressurized intraperitoneal aerosol chemotherapy (PIPAC)-directed therapy is a new treatment option for peritoneal metastasis (PM). The 4-tiered Peritoneal Regression Grading Score (PRGS) has been proposed for assessment of histological treatment response. We aimed to evaluate the effect of immunohistochemistry (IHC) on interobserver agreement of the PRGS. Hematoxylin and eosin (H&E)-stained and IHC-stained slides (n = 662) from 331 peritoneal quadrant biopsies (QBs) taken prior to 99 PIPAC procedures performed on 33 patients were digitalized and uploaded to a web library. Eight raters (five consultants and three residents) assessed the PRGS, and Krippendorff's alpha coefficients (α) were calculated. Results (IHC-PRGS) were compared with data published in 2019, using H&E-stained slides only (H&E-PRGS). Overall, agreement for IHC-PRGS was substantial to almost perfect. Agreement (all raters) regarding single QBs after treatment was substantial for IHC-PRGS (α = 0.69, 95% confidence interval [CI] = 0.66-0.72) and moderate for H&E-PRGS (α = 0.60, 95% CI = 0.56-0.64). Agreement (all raters) regarding the mean PRGS per QB set after treatment was higher for IHC-PRGS (α = 0.78, 95% CI = 0.73-0.83) than for H&E-PRGS (α = 0.71, 95% CI = 0.64-0.78). Among residents, agreement was almost perfect for IHC-PRGS and substantial for H&E-PRGS. Agreement (all raters) regarding maximum PRGS per QB set after treatment was substantial for IHC-PRGS (α = 0.61, 95% CI = 0.54-0.68) and moderate for H&E-PRGS (α = 0.60, 95% CI = 0.53-0.66). Among residents, agreement was substantial for IHC-PRGS (α = 0.66, 95% CI = 0.57-0.75) and moderate for H&E-PRGS (α = 0.55, 95% CI = 0.45-0.64). Additional IHC seems to improve the interobserver agreement of PRGS, particularly between less experienced raters

    Atmospheric impact of Arctic Sea ice loss in a coupled ocean–atmosphere simulation

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    The atmospheric response to an idealized decline in Arctic sea ice is investigated in a novel fully coupled climate model experiment. In this experiment two ensembles of single-year model integrations are performed starting on 1 April, the approximate start of the ice melt season. By perturbing the initial conditions of sea ice thickness (SIT), declines in both sea ice concentration and SIT, which result in sea ice distributions that are similar to the recent sea ice minima of 2007 and 2012, are induced. In the ice loss regions there are strong (~3 K) local increases in sea surface temperature (SST); additionally, there are remote increases in SST in the central North Pacific and subpolar gyre in the North Atlantic. Over the central Arctic there are increases in surface air temperature (SAT) of ~8 K due to increases in ocean–atmosphere heat fluxes. There are increases in SAT over continental North America that are in good agreement with recent changes as seen by reanalysis data. It is estimated that up to two-thirds of the observed increase in SAT in this region could be related to Arctic sea ice loss. In early summer there is a significant but weak atmospheric circulation response that projects onto the summer North Atlantic Oscillation (NAO). In early summer and early autumn there is an equatorward shift of the eddy-driven jet over the North Atlantic as a result of a reduction in the meridional temperature gradients. In winter there is no projection onto a particular phase of the NAO

    Polymorphisms in the SAA1/2 Gene Are Associated with Carotid Intima Media Thickness in Healthy Han Chinese Subjects: The Cardiovascular Risk Survey

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    BACKGROUND: Serum amyloid A protein (SAA) is not only an inflammatory factor, but also an apolipoprotein that can replace apolipoprotein A1 (apoA1) as the major apolipoprotein of high-density lipoprotein (HDL), which has been linked to atherosclerosis. However, the relationship between genetic polymorphisms of SAA and the intima-media thickness (IMT) of the common carotid artery in healthy subjects remains unclear. We investigated the role of SAA1 and SAA2 gene polymorphisms with IMT in a cohort of healthy subjects participating in the Cardiovascular Risk Survey (CRS) study. METHODOLOGY/PRINCIPAL FINDINGS: Anthropometric and B-mode ultrasound of the carotid IMT were measured in 1914 subjects (849 men; 1065 women) recruited from seven cities in Xinjiang province, (western China). Four SNPs (rs12218, rs2229338, rs1059559, and rs2468844) were genotyped by use of the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The SNP rs12218 was associated with carotid IMT by analyses of a dominate model (P<0.001) and additive model (P = 0.003), and the difference remained significant after multivariate adjustment (P = 0.008, P<0.001, respectively). This relationship was also observed in rs2468844 after multivariate adjustment by recessive model analysis (P = 0.011) but this was not observed in rs2229338 and rs1059559 before and after multivariate adjustment. These associations were not modified by serum HDL concentration. Furthermore, there were significant interactions between rs2468844 and rs12218 (interaction P<0.001) and rs2229338 (interaction P = 0.001) on carotid IMT. CONCLUSION/SIGNIFICANCE: Both rs12218 of the SAA1 gene and rs2468844 of SAA2 gene are associated with carotid IMT in healthy Han Chinese subjects

    Air temperature variations and gradients along the coast and fjords of western Spitsbergen

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    Daily temperature measurements from six meteorological stations along the coast and fjords of western Spitsbergen have been digitized and quality controlled in a Norwegian, Russian and Polish collaboration. Complete daily data series have been reconstructed back to 1948 for all of the stations. One of the station’s monthly temperature series has previously been extended back to 1898 and is included in this study. The long-term series show large temperature variability on western Spitsbergen with colder periods in the 1910s and 1960s and warmer periods in the 1930s, 1950s and in the 21st century. The most recent years are the warmest ones in the instrumental records. There is a positive and statistically significant trend in the annual times series for all of the stations; however, the strongest warming is seen in winter and spring. For the period 1979-2015, the linear trends range from 1.0 to 1.38°C/decade for the annual series and from 2.0 to 2.38°C/decade in winter. Threshold statistics demonstrate a decrease in the number of cold days per year and an increase in the number of warm days. A decreasing inter-annual variability is observed. In winter, spring and autumn, the stations in the northernmost areas of west Spitsbergen and in the innermost parts of Isfjorden are the coldest ones. In summer, however, the southernmost station is the coldest one

    The Atmosphere above Ny-Ålesund – Climate and global warming, ozone and surface UV radiation

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    The Arctic region is considered to be most sensitive to climate change, with warming in the Arctic occurring considerably faster than the global average due to several positive feedback mechanisms contributing to the “Arctic amplification”. Also the maritime and mountainous climate of Svalbard has undergone changes during the last decades. Here, the focus is set on the current atmospheric boundary conditions for the marine ecosystem in the Kongsfjorden area, discussed in the frame of long-term climatic observations in the larger regional and hemispheric context. During the last century, a general warming is found with temperature increases and precipitation changes varying in strength. During the last decades, a strong seasonality of the warming is observed in the Kongsfjorden area, with the strongest temperature increase occurring during the winter season. The winter warming is related to observed changes in the net longwave radiation. Moreover, changes in the net shortwave are observed during the summer period, attributed to the decrease in reflected radiation caused by the retreating snow cover. Another related aspect of radiation is the intensity of solar ultra-violet radiation that is closely coupled to the abundance of ozone in the column of air overhead. The long term evolution of ozone losses in the Arctic and their connection to climate change are discussed
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