4,115 research outputs found
Industrial specialisation and geographic concentration: Two sides of the same coin? Not for the European Union
Some recent studies have shown that specialisation of countries has tended to increase, while regional concentration of countries has tended to decrease. This seems to be counterintuitive at first glance. In this paper, we use the entropy index - as the indicator of structural change with the neatest aggregation properties to show how this divergence can happen. The main purpose of the paper is methodological, but we also apply the methodology to a specific case study: Manufacturing in the European Union since 1985. We confirm for this interesting period that increasing industrial specialisation has been offset by faster growth in the smaller Member States, with the net effect that industries have become somewhat less geographically concentrated. In terms of economic geography the evidence is in line with the second part of the inverted U-curve (where decreasing transport costs eventually foster de-concentration). This is no contradiction to increasing specialisation of countries in specific industries as predicted by many models in the old as well as the new trade theory.structural change, geographical concentration, industrial specialisation, European integration, entropy
The Livestock Economy of Pakistan: An Agricultural Sector Model Approach
The Pakistan Agricultural Sector Model (PASM) developed by Davies et al. (1991) was modified to enhance the livestock sub-sector. Nutrient-based rations replaced feedstuff-based rations and dry matter minimum and maximum constraints (stomach capacity) were added. Several initial simulations were undertaken to examine the structure of the modified model and its impact across the crop and livestock sub-sectors. These simulations included relaxing exogenous livestock numbers and selected crop hectarage constraints, and requiring that green forage be fed in the season grown. Most importantly, the results demonstrated that fodder hectarage will grow with livestock numbers to insure that sufficient green forage is available seasonally. Two other analyses were performed to demonstrate the need to specify linkages between the crop and livestock sub-sectors. An analysis of transforming the livestock sub-sector from traditional to feedlot-based technology demonstrated that the reduced numbers of non-milking cattle needed for a given output of meat would provide the potential for increased production of various crops and other livestock products. Also, expanded cotton and Irri rice exports, hypothesised to occur through trade liberalisation from the Uruguay Round of the GATT, highlighted other inter-relationships between the crop and livestock sub-sectors. Greater production of both livestock and other crops might accompany the expansion of cotton production but less livestock feed would be available with expanded exports of Irri rice.
ENVIRONMENTAL POLICY INFLUENCES ON LIVESTOCK STOCKING AND LOCATION DECISIONS
This paper explores the relationship between state level environmental regulations and stocking and location decisions in the U.S livestock and poultry industry (beef, chicken, dairy and hogs). Rather than conduct this analysis on a species-by-species basis, we choose to focus upon the overall size of the livestock industry (expressed in animal units) and the size of industry found on large, medium and small operations by state (48) and over time (28 yrs). Results indicate that industry may drive policy rather than the converse. However, since we also find that existing policy rules have differential impacts on the industry by operation size, we conclude that structural change in the industry may be driven in part by size or legal structure discriminating regulations.Demand and Price Analysis, Livestock Production/Industries,
An Error-Components Three-Stage Least-Squares Model of Investment Allocation by Farm Households
This paper is an assessment of patterns of investment by farm households via an econometric model adapted from a land allocation approach of Holt (1999). This analysis will shed light on the importance of different classes of assets to farm household well-being, and show the reaction of farm households to a variety of market, international and government effects.Farm Management,
The Livestock Economy of Pakistan: An Agricultural Sector Model Approach
The Pakistan Agricultural Sector Model (PASM) developed by
Davies et al. (1991) was modified to enhance the livestock sub-sector.
Nutrient-based rations replaced feedstuff-based rations and dry matter
minimum and maximum constraints (stomach capacity) were added. Several
initial simulations were undertaken to examine the structure of the
modified model and its impact across the crop and livestock sub-sectors.
These simulations included relaxing exogenous livestock numbers and
selected crop hectarage constraints, and requiring that green forage be
fed in the season grown. Most importantly, the results demonstrated that
fodder hectarage will grow with livestock numbers to insure that
sufficient green forage is available seasonally. Two other analyses were
performed to demonstrate the need to specify linkages between the crop
and livestock sub-sectors. An analysis of transforming the livestock
sub-sector from traditional to feedlot-based technology demonstrated
that the reduced numbers of non-milking cattle needed for a given output
of meat would provide the potential for increased production of various
crops and other livestock products. Also, expanded cotton and Irri rice
exports, hypothesised to occur through trade liberalisation from the
Uruguay Round of the GATT, highlighted other inter-relationships between
the crop and livestock sub-sectors. Greater production of both livestock
and other crops might accompany the expansion of cotton production but
less livestock feed would be available with expanded exports of Irri
rice
Population genetic structure between Yap and Palau for the coral Acropora hyacinthus
Information on connectivity is becoming increasingly in demand as marine protected areas are being designed as an integral part of a network to protect marine resources at the ecosystem level. Larval dispersal and population structure, however, remain very difficult to assess. Here, we tested the predictions of a detailed oceanographic connectivity model of larval dispersal and coral recruitment within Palau and between Palau and Yap, which was developed to support the review of the existing network of marine protected areas in Palau. We used high throughput microsatellite genotyping of the coral Acropora hyacinthus to characterize population genetic structure. Pairwise F ′ ST values between Palau and Yap (0.10), Palau and Ngulu (0.09) and Yap and Ngulu (0.09) were all significant and similar to pairwise F ′ ST values of sites within Palau (0.02–0.12) and within Yap (0.02–0.09) highlighting structure at island scale and indicating that recruitment may be even more localized than previously anticipated. A bottleneck test did not reveal any signs of a founder effect between Yap and Palau. Overall, the data supports the idea that recovery of A. hyacinthus in Palau did not come exclusively from a single source but most likely came from a combination of areas, including sites within Palau. In light of these results there seems to be very little connectivity around the barrier reef and management recommendation would be to increase the number or the size of MPAs within Palau
EPICOG-SCH: A brief battery to screen cognitive impact of schizophrenia in stable outpatients
Brief batteries in schizophrenia, are needed to screen for the cognitive impact of schizophrenia. We aimed to validate and co-norm the Epidemiological Study of Cognitive Impairment in Schizophrenia (EPICOG-SCH) derived brief cognitive battery. A cross-sectional outpatient evaluation was conducted of six-hundred-seventy-two patients recruited from 234 centers. The brief battery included well-known subtests available worldwide that cover cognitive domains related to functional outcomes: WAIS-III-Letter-Number-Sequencing-LNS, Category Fluency Test-CFT, Logical-Memory Immediate Recall-LM, and Digit-Symbol-Coding-DSC. CGI-SCH Severity and WHO-DAS-S were used to assess clinical severity and functional impairment, respectively. Unit Composite Score (UCS) and functional regression-weighted Composite Scores (FWCS) were obtained; discriminant properties of FWCS to identify patients with different levels of functional disability were analyzed using receiver-operating characteristic (ROC) technique. The battery showed good internal consistency, Cronbach's alpha = 0.78. The differences between cognitive performance across CGI-SCH severity level subscales ranged from 0.5 to 1 SD. Discriminant capacity of the battery in identifying patients with up to moderate disability levels showed fair discriminant accuracy with areas under the curve (AUC) > 0.70, p < 0.0001. An FWCS mean cut-off score ≥ 100 showed likelihood ratios (LR) up to 4.7, with an LR+ of 2.3 and a LR− of 0.5. An FWCS cut-off ≥ 96 provided the best balance between sensitivity (0.74) and specificity (0.62).
The EPICOG-SCH proved to be a useful brief tool to screen for the cognitive impact of schizophrenia, and its regression-weighted Composite Score was an efficient complement to clinical interviews for confirming patients' potential functional outcomes and can be useful for monitoring cognition during routine outpatient follow-up visits
A Phase I/IIa Safety and Efficacy Study of Nebulized Liposome-mediated Gene Therapy for Cystic Fibrosis Supports a Multidose Trial
Tuning the interactions between electron spins in fullerene-based triad systems
A series of six fullerene-linker-fullerene triads have been prepared by the stepwise addition of the fullerene cages to bridging moieties thus allowing the systematic variation of fullerene cage (C60 or C70) and linker (oxalate or terephthalate) and enabling precise control over the inter-fullerene separation. The fullerene triads exhibit good solubility in common organic solvents, have linear geometries and are diastereomerically pure. Cyclic voltammetric measurements demonstrate the excellent electron accepting capacity of all triads, with up to 6 electrons taken up per molecule in the potential range between -2.3 and 0.2 V (vs. Fc+/Fc). No significant electronic interactions between fullerene cages are observed in the ground state indicating that the individual properties of each C60 or C70 cage are retained within the triads. The electron-electron interactions in the electrochemically generated dianions of these triads, with one electron per fullerene cage were studied by EPR spectroscopy. The nature of electron-electron coupling observed at 77 K can be described as an equilibrium between a doublet and triplet state biradical which depends on the interfullerene spacing. The shorter oxalate-bridged triads exhibit stronger spin-spin coupling with triplet character, while in the longer terephthalate-bridged triads the intramolecular spin-spin coupling is significantly reduced
Crystal Structure of a Deacylation-defective Mutant of Penicillin-binding Protein 5 at 2.3-Å Resolution
Penicillin-binding protein 5 (PBP 5) of Escherichia coli functions as a d-alanine carboxypeptidase, cleaving the C-terminal d-alanine residue from cell wall peptides. Like all PBPs, PBP 5 forms a covalent acyl-enzyme complex with beta-lactam antibiotics; however, PBP 5 is distinguished by its high rate of deacylation of the acyl-enzyme complex (t(12) approximately 9 min). A Gly-105 --> Asp mutation in PBP 5 markedly impairs this beta-lactamase activity (deacylation), with only minor effects on acylation, and promotes accumulation of a covalent complex with peptide substrates. To gain further insight into the catalytic mechanism of PBP 5, we determined the three-dimensional structure of the G105D mutant form of soluble PBP 5 (termed sPBP 5') at 2.3 A resolution. The structure is composed of two domains, a penicillin binding domain with a striking similarity to Class A beta-lactamases (TEM-1-like) and a domain of unknown function. In addition, the penicillin-binding domain contains an active site loop spatially equivalent to the Omega loop of beta-lactamases. In beta-lactamases, the Omega loop contains two amino acids involved in catalyzing deacylation. This similarity may explain the high beta-lactamase activity of wild-type PBP 5. Because of the low rate of deacylation of the G105D mutant, visualization of peptide substrates bound to the active site may be possible
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