254 research outputs found
Regional Agricultural Policy Design on the Basis of a Detailed Linear Economic and Agrotechnical Model
The use of a large-scale LP agricultural model for supporting the policy design process is presented. The model determines the agricultural crop and livestock specialization in a detailed, disaggregated form, i.e. distributed over subregions, properties, sail qualities, technologies, etc. and basic financial and material flaws, all in given natural conditions, e.g. sail qualities, and available resources, e.g. manpower, machinery, capital, etc. The policy is meant in terms of imposed price structure and resource distribution. The use of information obtainable from both primal and dual solution is shown. The results of implementation for a region in Poland are presented
A General Regional Agricultural Model (GRAM) Applied to a Region in Poland
The General Regional Agricultural Model (GRAM) described in this report is the product of a case study of regional development in the Upper Notec region of Poland carried out collaboratively by IIASA and the Systems Research Institute in Warsaw, Poland. The purpose of this work was twofold: to assist Polish authorities in planning the development of agriculture in the region, and to create a universal methodology in the form of a model applicable to similar problems and settings in other countries. Thus, the methodological characteristics presented in this report are based on testing and implementing the model in the concrete situation of the Upper Notec region of Poland.
GRAM was developed using the so-called "bottom-up" approach, which consists of orienting the model toward technological interdependencies at the level of the agricultural areas in the region, and including a set of variables and parameters that enable this "bottom" model to be linked with those for other aspects of the regional economy.
The model deals with the following elements: a set of crops, a number of rotation groups; types of agricultural animals, types of livestock products, and feed components in forage; three types of market and three types of land ownership; different crop growing and livestock breeding technologies; and different soil qualities and types of fertilizers according to the contents of the elements. The model incorporates space and can give solutions for a number of regions. Technically GRAM is a large linear programming model with static relations.
The purpose of the model is to derive a detailed specification for a production structure combined with a direct utilization of its products that is optimal for a predefined objective. The model can also be used to indicate essential bottlenecks, resource distribution inconsistencies, and so on. It allows the formulations of multi-objective optimization problems to consider conflicts between different groups of producers. It is solved under constraints in labor, machinery, fertilizers and water availability at annual and two peak levels.
Two types of objective functions are used: monetary (linked with cost-benefit analysis) and physical. Among specific objective for which the model has been solved there are: total net return or net production value from agricultural activities within the region; balance of regional agricultural production in monetary terms; regional agricultural production in terms of nutrition units; regional trade balances in livestock products in monetary terms and nutrition units; and export production in monetary terms. In cooperation with other elements of the regional model system, two types of information are exchanged: dual prices and volume of output
ERG Induces Epigenetic Activation of Tudor Domain-Containing Protein 1 (TDRD1) in ERG Rearrangement-Positive Prostate Cancer
Background Overexpression of ERG transcription factor due to genomic ERG-
rearrangements defines a separate molecular subtype of prostate tumors. One of
the consequences of ERG accumulation is modulation of the cellâs gene
expression profile. Tudor domain-containing protein 1 gene (TDRD1) was
reported to be differentially expressed between TMPRSS2:ERG-negative and
TMPRSS2:ERG-positive prostate cancer. The aim of our study was to provide a
mechanistic explanation for the transcriptional activation of TDRD1 in ERG
rearrangement-positive prostate tumors. Methodology/Principal Findings Gene
expression measurements by real-time quantitative PCR revealed a remarkable
co-expression of TDRD1 and ERG (r2 = 0.77) but not ETV1 (r2<0.01) in human
prostate cancer in vivo. DNA methylation analysis by MeDIP-Seq and bisulfite
sequencing showed that TDRD1 expression is inversely correlated with DNA
methylation at the TDRD1 promoter in vitro and in vivo (Ï = â0.57).
Accordingly, demethylation of the TDRD1 promoter in TMPRSS2:ERG-negative
prostate cancer cells by DNA methyltransferase inhibitors resulted in TDRD1
induction. By manipulation of ERG dosage through gene silencing and forced
expression we show that ERG governs loss of DNA methylation at the TDRD1
promoter-associated CpG island, leading to TDRD1 overexpression.
Conclusions/Significance We demonstrate that ERG is capable of disrupting a
tissue-specific DNA methylation pattern at the TDRD1 promoter. As a result,
TDRD1 becomes transcriptionally activated in TMPRSS2:ERG-positive prostate
cancer. Given the prevalence of ERG fusions, TDRD1 overexpression is a common
alteration in human prostate cancer which may be exploited for diagnostic or
therapeutic procedures
Representing uncertainty regarding satisfaction degrees using possibility distributions
Evaluating flexible criteria on data leads to degrees of satisfaction. If a datum is uncertain, it can be uncertain to which degree it satisfies the criterion. This uncertainty can be modelled using a possibility distribution over the domain of possible degrees of satisfaction. In this work, we discuss the meaningfulness thereof by looking at the semantics of such a representation of the uncertainty. More specifically, it is shown that defuzzification of such a representation, towards usability in (multi-criteria) decision support systems, corresponds to expressing a clear attitude towards uncertainty (optimistic, pessimistic, cautious, etc.
Determination of the primary structure and carboxyl pKAs of heparin-derived oligosaccharides by band-selective homonuclear-decoupled two-dimensional 1H NMR
Determination of the structure of heparin-derived oligosaccharides by 1H NMR is challenging because resonances for all but the anomeric protons cover less than 2 ppm. By taking advantage of increased dispersion of resonances for the anomeric H1 protons at low pD and the superior resolution of band-selective, homonuclear-decoupled (BASHD) two-dimensional 1H NMR, the primary structure of the heparin-derived octasaccharide âUA(2S)-[(1âââ4)-GlcNS(6S)-(1âââ4)-IdoA(2S)-]3-(1âââ4)-GlcNS(6S) has been determined, where âUA(2S) is 2-O-sulfated â4,5-unsaturated uronic acid, GlcNS(6S) is 6-O-sulfated, N-sulfated ÎČ-d-glucosamine and IdoA(2S) is 2-O-sulfated α-l-iduronic acid. The spectrum was assigned, and the sites of N- and O-sulfation and the conformation of each uronic acid residue were established, with chemical shift data obtained from BASHD-TOCSY spectra, while the sequence of the monosaccharide residues in the octasaccharide was determined from inter-residue NOEs in BASHD-NOESY spectra. Acid dissociation constants were determined for each carboxylic acid group of the octasaccharide, as well as for related tetra- and hexasaccharides, from chemical shiftâpD titration curves. Chemical shiftâpD titration curves were obtained for each carboxylic acid group from sub-spectra taken from BASHD-TOCSY spectra that were measured as a function of pD. The pKAs of the carboxylic acid groups of the âUA(2S) residues are less than those of the IdoA(2S) residues, and the pKAs of the carboxylic acid groups of the IdoA(2S) residues for a given oligosaccharide are similar in magnitude. Relative acidities of the carboxylic acid groups of each oligosaccharide were calculated from chemical shift data by a pH-independent method
The Role of Graduality for Referring Expression Generation in Visual Scenes
International audienceReferring Expression Generation (reg) algorithms, a core component of systems that generate text from non-linguistic data, seek to identify domain objects using natural language descriptions. While reg has often been applied to visual domains, very few approaches deal with the problem of fuzziness and gradation. This paper discusses these problems and how they can be accommodated to achieve a more realistic view of the task of referring to objects in visual scenes
Inhibition of cathepsin B by caspase-3 inhibitors blocks programmed cell death in <i>Arabidopsis</i>
Programmed cell death (PCD) is used by plants for development and survival to biotic and abiotic stresses. The role of caspases in PCD is well established in animal cells. Over the past 15 years, the importance of caspase-3-like enzymatic activity for plant PCD completion has been widely documented despite the absence of caspase orthologues. In particular, caspase-3 inhibitors blocked nearly all plant PCD tested. Here, we affinity-purified a plant caspase-3-like activity using a biotin-labelled caspase-3 inhibitor and identified Arabidopsis thaliana cathepsin B3 (AtCathB3) by liquid chromatography with tandem mass spectrometry (LC-MS/MS). Consistent with this, recombinant AtCathB3 was found to have caspase-3-like activity and to be inhibited by caspase-3 inhibitors. AtCathepsin B triple-mutant lines showed reduced caspase-3-like enzymatic activity and reduced labelling with activity-based caspase-3 probes. Importantly, AtCathepsin B triple mutants showed a strong reduction in the PCD induced by ultraviolet (UV), oxidative stress (H2O2, methyl viologen) or endoplasmic reticulum stress. Our observations contribute to explain why caspase-3 inhibitors inhibit plant PCD and provide new tools to further plant PCD research. The fact that cathepsin B does regulate PCD in both animal and plant cells suggests that this protease may be part of an ancestral PCD pathway pre-existing the plant/animal divergence that needs further characterisation
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