2,491 research outputs found
Modelling the EC Agricultural Sector: Problem Assessment, Policy Scenarios and Model Outline
This paper is composed of three parts: the first section describes the economic situation and past development within the nine member countries of the European Community (EC). Particular emphasis is given to resource and production structure in agriculture as well as agricultural commodity markets. The second part contains a description of the Common Agricultural Policy (CAP) which is evaluated w.r.t., it's effects on member and non-member countries. This section contains also a discussion of alternative policy scenarios conceivable for later model applications.
The third part of this paper gives a brief overview over the structure of the Agricultural Sector Model. This includes a presentation of the macro model with intersectoral linkages between agriculture and the rest of the economy as well as a mathematical formulation of the farm resource and allocation model
The Food and Agriculture Model of the International Institute for Applied Systems Analysis
The report summarizes objectives and scope of a global system of national agricultural sector models which is currently being developed as part of the Food and Agriculture Program at IIASA.
The paper starts with a very brief characterization of the recent world food situation. It is emphasized that the main efforts to overcome current and expected food scarcities will have to be made within the affected developing nations themselves. International food policies, however, will have an important role to play in supporting these efforts. Three problem domains of international relevance are briefly discussed| instability of world markets, insecurity of food aid and deterioration of international trade.
The third section contains a summary of available global models insofar as they emphasize food and agriculture. No results or policy recommendations are reported here, rather the basic structural differences are discussed.
This schematic comparison of models leads then to a more detailed discussion of the international food and agriculture model of IIASA. The objective of the IIASA program is to define and quantify alternative sets of international and national policies which seem appropriate to reduce world hunger within the next 5-15 years by exploiting the international interactions between developing and industrial nations and by increasing local production in developing countries. The emphasis of the program lies on international cooperation.
A stepwise procedure is envisaged, where in the first phase a set of national agricultural sector models will be specified and empirically tested which will then, during the second phase, be linked through a world consistency model to simulate the global system. The national models will have some common properties to achieve operationality. They will typically consist of a disaggregated agricultural production component, an aggregated submodel for the rest of the economy as well as a consistent national expenditure system. These components define a so-called "real world bloc" which is controlled by a "policy bloc" describing goals and instruments at the government decision level
Clozapine once- versus multiple-daily dosing: a two-center cross-sectional study, systematic review and meta-analysis.
Evidence regarding effectiveness and safety of clozapine once- vs. multiple-daily dosing is limited. We compared demographic and clinical parameters between patients with once- vs. multiple-daily dosing in the Department of Psychiatry and Psychotherapy, University of Regensburg, Germany (AGATE dataset), and the Department of Psychiatry, Lausanne University Hospital, Switzerland, using non-parametric tests. Effectiveness and safety outcomes were available in the AGATE dataset. We performed a systematic review in PubMed/Embase until February 2022, meta-analyzing studies comparing clozapine once- vs. multiple-daily-dosing. We estimated a pooled odds ratio for adverse drug-induced reactions (ADRs) and meta-analyzed differences regarding clinical symptom severity, age, percentage males, smokers, clozapine dose, and co-medications between patients receiving once- vs. multiple-daily dosing. Study quality was assessed using the Newcastle-Ottawa-Scale. Of 1494 and 174 patients included in AGATE and Lausanne datasets, clozapine was prescribed multiple-daily in 74.8% and 67.8%, respectively. In the AGATE cohort, no differences were reported for the clinical symptoms severity or ADR rate (p > 0.05). Meta-analyzing eight cohorts with a total of 2810 clozapine-treated individuals, we found more severe clinical symptoms (p = 0.036), increased ADR risk (p = 0.01), higher clozapine doses (p < 0.001), more frequent co-medication with other antipsychotics (p < 0.001), benzodiazepines (p < 0.001), anticholinergics (p = 0.039), and laxatives (p < 0.001) in patients on multiple- vs. once-daily dosing. Of six studies, five were rated as good, and one as poor quality. Patients responding less well to clozapine may be prescribed higher doses multiple-daily, also treated with polypharmacy, potentially underlying worse safety outcomes. Patient preferences and adherence should be considered during regimen selection
Concentration Dependence of Superconductivity and Order-Disorder Transition in the Hexagonal Rubidium Tungsten Bronze RbxWO3. Interfacial and bulk properties
We revisited the problem of the stability of the superconducting state in
RbxWO3 and identified the main causes of the contradictory data previously
published. We have shown that the ordering of the Rb vacancies in the
nonstoichiometric compounds have a major detrimental effect on the
superconducting temperature Tc.The order-disorder transition is first order
only near x = 0.25, where it cannot be quenched effectively and Tc is reduced
below 1K. We found that the high Tc's which were sometimes deduced from
resistivity measurements, and attributed to compounds with .25 < x < .30, are
to be ascribed to interfacial superconductivity which generates spectacular
non-linear effects. We also clarified the effect of acid etching and set more
precisely the low-rubidium-content boundary of the hexagonal phase.This work
makes clear that Tc would increase continuously (from 2 K to 5.5 K) as we
approach this boundary (x = 0.20), if no ordering would take place - as its is
approximately the case in CsxWO3. This behaviour is reminiscent of the
tetragonal tungsten bronze NaxWO3 and asks the same question : what mechanism
is responsible for this large increase of Tc despite the considerable
associated reduction of the electron density of state ? By reviewing the other
available data on these bronzes we conclude that the theoretical models which
are able to answer this question are probably those where the instability of
the lattice plays a major role and, particularly, the model which call upon
local structural excitations (LSE), associated with the missing alkali atoms.Comment: To be published in Physical Review
Nationwide Outcome of Tailored Surgery for Symptomatic Chronic Pancreatitis based on Pancreatic Morphology:Validation of the International guidelines
OBJECTIVE: To determine the nationwide use and outcome of tailored surgical treatment for symptomatic chronic pancreatitis (CP) as advised by recent guidelines.SUMMARY BACKGROUND DATA: Randomized trials have shown that surgery is superior to endoscopy in patients with symptomatic CP, although endoscopy remains popular Recent guidelines advice to "tailor surgery" based on pancreatic morphology meaning that the least extensive procedure should be selected based on pancreatic morphology. However, nationwide, and multicenter studies On tailored surgery for symptomatic CP are lacking.METHODS: Nationwide multicenter retrospective analysis of consecutive patients undergoing surgical treatment for symptomatic CP in all seven Dutch university medical centers (2010-2020). Outcomes included volume trend, major complications, 90-day mortality, postoperative opioid use and clinically relevant pain relief. Surgical treatment was tailored based on the size of the main pancreatic duct and pancreatic head (e.g. surgical drainage for a dilated pancreatic duct, and normal size pancreatic head).RESULTS: Overall, 381 patients underwent surgery for CP: 127 surgical drainage procedures ( 33%; mostly extended lateral pancreaticojejunostomy), 129 duodenum-preserving pancreatic head resections (DPPHR, 34%, mostly Frey), and 125 formal pancreatic resections (33%, mostly distal pancreatectomy). The annual surgical volume increased slightly (Pearson r=0.744). Mortality (90-day) occurred in 6 patients (2%), and was non-significantly lower after surgical drainage (0%, 3%, 2%; P =0.139). Major complications (12%, 24%, 26%; P =0.012), postoperative pancreatic fistula grade B/C (0%, 3%, 22%; P =0.038), surgical reintervention (4%, 16%, 12%; P =0.006), and endocrine insufficiency ( 14%, 21%, 43%; P <0.001) occurred less often after surgical drainage. After a median follow-up of 11 months [IQR 3-23] good rates of clinically relevant pain relief ( 83%, 69%, 80%; P =0.082) were observed and 81% of opioid users had stopped using (83%, 78%, 84%, P =0.496).CONCLUSION: The use of surgery for symptomatic CP increased over the study period. Drainage procedures were associated with the best safety profile and excellent functional outcome, highlighting the importance of tailoring surgery based on pancreatic morphology.</p
Nationwide Outcome of Tailored Surgery for Symptomatic Chronic Pancreatitis based on Pancreatic Morphology:Validation of the International guidelines
OBJECTIVE: To determine the nationwide use and outcome of tailored surgical treatment for symptomatic chronic pancreatitis (CP) as advised by recent guidelines.SUMMARY BACKGROUND DATA: Randomized trials have shown that surgery is superior to endoscopy in patients with symptomatic CP, although endoscopy remains popular Recent guidelines advice to "tailor surgery" based on pancreatic morphology meaning that the least extensive procedure should be selected based on pancreatic morphology. However, nationwide, and multicenter studies On tailored surgery for symptomatic CP are lacking.METHODS: Nationwide multicenter retrospective analysis of consecutive patients undergoing surgical treatment for symptomatic CP in all seven Dutch university medical centers (2010-2020). Outcomes included volume trend, major complications, 90-day mortality, postoperative opioid use and clinically relevant pain relief. Surgical treatment was tailored based on the size of the main pancreatic duct and pancreatic head (e.g. surgical drainage for a dilated pancreatic duct, and normal size pancreatic head).RESULTS: Overall, 381 patients underwent surgery for CP: 127 surgical drainage procedures ( 33%; mostly extended lateral pancreaticojejunostomy), 129 duodenum-preserving pancreatic head resections (DPPHR, 34%, mostly Frey), and 125 formal pancreatic resections (33%, mostly distal pancreatectomy). The annual surgical volume increased slightly (Pearson r=0.744). Mortality (90-day) occurred in 6 patients (2%), and was non-significantly lower after surgical drainage (0%, 3%, 2%; P =0.139). Major complications (12%, 24%, 26%; P =0.012), postoperative pancreatic fistula grade B/C (0%, 3%, 22%; P =0.038), surgical reintervention (4%, 16%, 12%; P =0.006), and endocrine insufficiency ( 14%, 21%, 43%; P <0.001) occurred less often after surgical drainage. After a median follow-up of 11 months [IQR 3-23] good rates of clinically relevant pain relief ( 83%, 69%, 80%; P =0.082) were observed and 81% of opioid users had stopped using (83%, 78%, 84%, P =0.496).CONCLUSION: The use of surgery for symptomatic CP increased over the study period. Drainage procedures were associated with the best safety profile and excellent functional outcome, highlighting the importance of tailoring surgery based on pancreatic morphology.</p
Differential branching fraction and angular analysis of the decay B0âKâ0ÎŒ+ÎŒâ
The angular distribution and differential branching fraction of the decay B 0â K â0 ÎŒ + ÎŒ â are studied using a data sample, collected by the LHCb experiment in pp collisions at sâ=7 TeV, corresponding to an integrated luminosity of 1.0 fbâ1. Several angular observables are measured in bins of the dimuon invariant mass squared, q 2. A first measurement of the zero-crossing point of the forward-backward asymmetry of the dimuon system is also presented. The zero-crossing point is measured to be q20=4.9±0.9GeV2/c4 , where the uncertainty is the sum of statistical and systematic uncertainties. The results are consistent with the Standard Model predictions
Observation of an Excited Bc+ State
Using pp collision data corresponding to an integrated luminosity of 8.5 fb-1 recorded by the LHCb experiment at center-of-mass energies of s=7, 8, and 13 TeV, the observation of an excited Bc+ state in the Bc+Ï+Ï- invariant-mass spectrum is reported. The observed peak has a mass of 6841.2±0.6(stat)±0.1(syst)±0.8(Bc+) MeV/c2, where the last uncertainty is due to the limited knowledge of the Bc+ mass. It is consistent with expectations of the Bcâ(2S31)+ state reconstructed without the low-energy photon from the Bcâ(1S31)+âBc+Îł decay following Bcâ(2S31)+âBcâ(1S31)+Ï+Ï-. A second state is seen with a global (local) statistical significance of 2.2Ï (3.2Ï) and a mass of 6872.1±1.3(stat)±0.1(syst)±0.8(Bc+) MeV/c2, and is consistent with the Bc(2S10)+ state. These mass measurements are the most precise to date
Search for the decay Bs0âD*âϱ
A search for the decay Bs0âD*âϱ is presented using a data sample corresponding to an integrated luminosity of 1.0ââfb-1 of pp collisions collected by LHCb. This decay is expected to be mediated by a W-exchange diagram, with little contribution from rescattering processes, and therefore a measurement of the branching fraction will help us to understand the mechanism behind related decays such as Bs0âÏ+Ï- and Bs0âDD- . Systematic uncertainties are minimized by using B0âD*âϱ as a normalization channel. We find no evidence for a signal, and set an upper limit on the branching fraction of B(Bs0âD*âϱ)<6.1(7.8)Ă10-6 at 90% (95%) confidence level
Measurements of the branching fractions of B+âppK+ decays
The branching fractions of the decay B+ â ppÌK+ for different intermediate states are measured using data, corresponding to an integrated luminosity of 1.0 fb-1, collected by the LHCb experiment. The total branching fraction, its charmless component MppÌ < 2.85 GeV/c2 and the branching fractions via the resonant ccÌ states η c(1S) and Ï(2S) relative to the decay via a J/Ï intermediate state are [Equation not available: see fulltext.] Upper limits on the B + branching fractions into the η c(2S) meson and into the charmonium-like states X(3872) and X(3915) are also obtained
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