49 research outputs found

    Multi-Output Broadacre Agricultural Production: Estimating A Cost Function Using Quasi-Micro Farm Level Data From Australia

    Get PDF
    Existing econometric models for Australian broadacre agricultural production are few and have become dated. This paper estimates a multi-product restricted cost function using a unique quasi-micro farm level dataset from the Australian Agricultural and Grazing Industries Survey. Both the transcendental logarithmic and normalized quadratic functional forms are employed. Heteroskedasticity caused by the particular nature of the quasi-micro data is also assessed and accommodated. Allen partial elasticities of input substitution and own-and cross-price input demand elasticities are computed. The estimated demands for most production factors are inelastic to prices. Hired labour is responsive to own price and cropping input prices.Production Economics, Research Methods/ Statistical Methods,

    Nonsimultaneity and Futures Option Pricing: Simulation and Empirical Evidence

    Get PDF
    Empirical tests of option pricing models are joint tests of the 'correctness' of the model, the efficiency of the market and the simultaneity of price observations. Some degree of nonsimultaeity can be expected in all but the most liquid markets and is therefore evident in many non-US markets. Simulation results indicate that nonsimultaneity is potentially a significant problem in empirical tests of futures option pricing models. Empirical results using Australian data show that a five-minute window for matching transactions does not remove the nonsimultaneity bias for near-the-money and out-of-the money options. A more accurate matching may therefore be required. The nonsimultaneity bias is effectively removed if a five-minute window is employed for in-the-money options.Nonsimultaneity; Futures option; Mispricing

    ON THE ESTIMATION OF DEMAND SYSTEMS WITH LARGE NUMBER OF GOODS: AN APPLICATION TO SOUTH AFRICA HOUSEHOLD FOOD DEMAND

    Get PDF
    The estimation of large demand systems to investigate the patterns of consumption of households is notoriously difficult. This study develops a modified Almost Ideal Demand System model based on a flexible two-stage budgeting demand modelling framework to examine the effect of estimation procedures (Bottom-up and Top-down) on South African household food consumption parameters. Household food consumption was divided into seven broad food groups: meat and fish; grains; dairy products; fruits; vegetables; other foods. The demand systems were estimated using data from the 1993 South Africa Integrated Household Survey (SIHS) conducted by the South African Labour and Development Research Unit (SALDRU). Empirical results indicate that the Top-down approach is more suited for estimation of South African household food demand. Results indicate that own-price do play an important role in influencing household food consumption. Results also indicate no presence of gross substitution between and within food groups. Expenditure elasticity estimates indicate that meat and fish, dairy products and fruits are luxury products, while grains, vegetables and other foods are necessities in South African household diet.Consumer/Household Economics, Research Methods/ Statistical Methods,

    A double-blind, randomized, placebo-controlled trial of prostaglandin E 1 in liver transplantation

    Full text link
    A double-blind placebo-controlled trial of intravenous prostaglandin PGE 1 (40 Μg/h) was conducted in adult orthotopic liver transplant recipients. Infusion was started intraoperatively and continued for up to 21 days. Patients were followed up for 180 days postoperatively. Among 172 patients eligible for treatment in the study, 160 could be evaluated (78 PGE 1 ; 82 placebo). Patient and graft survival were similar (PGE 1 : 16 deaths, 9 retransplantations [7 survivors]; controls: 15 deaths, 6 retransplantations [3 survivors]). In patients with surviving grafts, however, PGE 1 administration resulted in a 23% shorter mean duration of hospitalization following transplantation (PGE 1 : 24.4 days; controls: 31.8 days; P = .02) and 40% shorter length of time postoperatively in the intensive care unit (PGE 1 : 8.2 days; controls 13.7 days; P = .05). Reduced needs for renal support ( P = .03) or surgical intervention other than retransplantation ( P = .02) were also noted with PGE 1 use. Further, PGE 1 administration resulted in a trend toward improved survival rates in patients with mild renal impairment (preoperative serum creatinine 1.5 mg percent or greater; P = .08). Neither the incidence of acute cellular rejection nor of primary nonfunction was significantly different in the two groups. Phlebitis was the only complication that was more common during PGE 1 administration, (PGE 1 : 9; controls: 4). These results suggest that PGE 1 use in hepatic allograft recipients reduces morbidity and may result in sizable cost reductions. (H EPATOLOGY 1995;21:366–372.)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/38409/1/1840210216_ftp.pd

    Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans

    Get PDF
    Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in 25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16 regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP, while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium (LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region. Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa, an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent signals within the same regio

    Basic science232. Certolizumab pegol prevents pro-inflammatory alterations in endothelial cell function

    Get PDF
    Background: Cardiovascular disease is a major comorbidity of rheumatoid arthritis (RA) and a leading cause of death. Chronic systemic inflammation involving tumour necrosis factor alpha (TNF) could contribute to endothelial activation and atherogenesis. A number of anti-TNF therapies are in current use for the treatment of RA, including certolizumab pegol (CZP), (Cimzia ®; UCB, Belgium). Anti-TNF therapy has been associated with reduced clinical cardiovascular disease risk and ameliorated vascular function in RA patients. However, the specific effects of TNF inhibitors on endothelial cell function are largely unknown. Our aim was to investigate the mechanisms underpinning CZP effects on TNF-activated human endothelial cells. Methods: Human aortic endothelial cells (HAoECs) were cultured in vitro and exposed to a) TNF alone, b) TNF plus CZP, or c) neither agent. Microarray analysis was used to examine the transcriptional profile of cells treated for 6 hrs and quantitative polymerase chain reaction (qPCR) analysed gene expression at 1, 3, 6 and 24 hrs. NF-κB localization and IκB degradation were investigated using immunocytochemistry, high content analysis and western blotting. Flow cytometry was conducted to detect microparticle release from HAoECs. Results: Transcriptional profiling revealed that while TNF alone had strong effects on endothelial gene expression, TNF and CZP in combination produced a global gene expression pattern similar to untreated control. The two most highly up-regulated genes in response to TNF treatment were adhesion molecules E-selectin and VCAM-1 (q 0.2 compared to control; p > 0.05 compared to TNF alone). The NF-κB pathway was confirmed as a downstream target of TNF-induced HAoEC activation, via nuclear translocation of NF-κB and degradation of IκB, effects which were abolished by treatment with CZP. In addition, flow cytometry detected an increased production of endothelial microparticles in TNF-activated HAoECs, which was prevented by treatment with CZP. Conclusions: We have found at a cellular level that a clinically available TNF inhibitor, CZP reduces the expression of adhesion molecule expression, and prevents TNF-induced activation of the NF-κB pathway. Furthermore, CZP prevents the production of microparticles by activated endothelial cells. This could be central to the prevention of inflammatory environments underlying these conditions and measurement of microparticles has potential as a novel prognostic marker for future cardiovascular events in this patient group. Disclosure statement: Y.A. received a research grant from UCB. I.B. received a research grant from UCB. S.H. received a research grant from UCB. All other authors have declared no conflicts of interes

    Finishing the euchromatic sequence of the human genome

    Get PDF
    The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

    RELATIVE COST-EFFECTIVENESS OF INPUT AND OUTPUT SUBSIDIES

    No full text
    A subsidy on a single input is compared with an output subsidy as a means of stimulating output, and the conditions under which the single input subsidy is (a) more treasury cost-effective and (b) overall the more socially efficient measure, are explored. Rationalisations for input subsidies, particularly fertiliser subsidies, are examined in the light of the results

    AJAE Appendix: The Benefit Function Approach to Modeling Price-Dependent Demand Systems: An Application of Duality Theory

    No full text
    The material contained herein is supplementary to the article named in the title and published in the American Journal of Agricultural Economics.Demand and Price Analysis,
    corecore