1,266 research outputs found
Climate Change and Crop Yield Distribution: Some New Evidence From Panel Data Models
This study examines the impact of climate on the yields of seven major crops in Taiwan based on pooled panel data for 15 prefectures over the 1977-1996 period. Unit-root tests and maximum likelihood methods involving a panel data model are explored to obtain reliable estimates. The results suggest that climate has different impacts on different crops and a gradual increase in crop yield variation is expected as global warming prevails. Policy measures to counteract yield variability should therefore be carefully evaluated to protect farmers from exposure to these long-lasting and increasingly climate-related risks.Yield response, Climate change, Panel data, Unit-root test
Is Contract Farming More Profitable and Efficient Than Non-Contract Farming-A Survey Study of Rice Farms In Taiwan
Trade liberalization and globalization has modernized the food retail sector in Taiwan, affecting consumers, producers and trade patterns. These changes have placed significant pressures on farmers and processors including more stringent quality control and product varieties. The government has launched a rice production-marketing contract program in 2005 to assist rice farmers and the agro-business sector to work together as partners. The minimum scale for each contract is 50 hectares of adjacent rice paddies with 50 participants including rice farmers, seedling providers, millers and marketing agents. In order to evaluate the outcome of this program, a survey is conducted in the summer of 2005 after the first (spring) crop is harvested. Information of price and value of output and major variable and fixed inputs are collected along with characteristics of the farmers and farms. The survey results show that the average revenue of a contract farm is about 11 percent higher than an average non-contract farm. The per hectare cost of production in a contract farm is about 13 percent lower and as a result the average profit margin under contract is more than 50 percent above those without contract. A swtiching regression profit frontier model is adopted to further investigate their efficiency performance. The result indicates that an average contract farms is 20 percent more efficient than an average non-contract farm in a comparable operating environment. The result also suggests that although contract farming has potential to improve the profit of smallholders, it is not a sufficient condition for such improvement.Land Economics/Use,
ON THE EQUIVALENCE OF IMPORT TARIFF AND QUOTA: THE CASE OF RICE IMPORT IN TAIWAN
This paper extends the existing theory on the equivalence of import tariff and quota. If the equivalence is defined on the domestic price level (weak equivalence), then either the zero conjectural variation for domestic country or a perfectly competitive market will be sufficient to support this equivalence. If the equivalence is defined both on the same domestic price level as well as tariff rate (strong equivalence), then the conditions are that either domestic country acts as a Cournot competitor and foreign country is a price taker, or both domestic and foreign country are price takers. An empirical spatial-equilibrium trade model is constructed to simulate the impacts of import tariff and quota. Using Taiwan¡¦s rice import as an example, the empirical results show that if Taiwan switches from the quota system to tariff system, the domestic rice price as well as total social welfare can be increased given the same import volume.International Relations/Trade,
SPATIAL EQUILIBRIUM MODELING WITH IMPERFECTLY COMPETITIVE MARKETS: AN APPLICATION TO RICE TRADE
A general imperfect competition spatial equilibrium model is developed to estimate the trading country behaviors in the international rice market using a conjectural variation approach. Such a model allows the possibility of an imperfect competitive market to exit on both the export and import sides without any assumption of market structure. The empirical results show that the major exporting countries, Thailand, Vietnam, and the U.S. acted as high degree of imperfect competitors(or oligopolies) while Pakistan acted as a lower degree of imperfect competitor. The importing countries such as Japan, the Philippines, Europe, Brazil, and the former USSR behaved as high degree of imperfect competitors (or oligopsonies). The empirical results also show that there are welfare gains of $1,492 million when all trading countries comply with the free trade agreement.Marketing,
Solid Pseudopapillary Neoplasm of the Pancreas: Report of Two Cases and Review of the Literature
AbstractSolid pseudopapillary neoplasm (SPN) of the pancreas is a rare low-grade malignant-potential epithelial tumor that predominantly affects young women aged 20–35 years with a mean age of 22 years. It is currently categorized in the World Health Organization classification under exocrine pancreatic tumor. Here, we present two cases of SPN with initial presentation of large intra-abdominal masses. Both patients underwent successful en bloc distal pancreatectomy and splenectomy. Local recurrence and distant metastasis were not detected at the follow up at 21 months and 9 years respectively. In summary, a large, well-encapsulated cystic mass in the pancreas of a young woman should raise suspicion of SPN
Towards An Integrated Effort For Managing IT Process Standards Implementation
Adopting IT process standards seems to be a trend for IT organizations to meet ad-hoc informational needs and to provide better business value. Due to the changing environments of IT organizations themselves, one key to IT success lies in not only the establishment, but also the sustainability of ad-hoc professional IT functions. As IT organizations face many kinds of process standards to implement for various IT functions and although the implementations may be different due to various IT domains, from the management point of view, these implementations may not exist individually. This article attempts to highlight a possibility of an integrated effort to effectively manage the implementations of IT standards in an IT organization. Such a shared management refers to the integrated institutionalization design, which provides a road map for all IT functions to systematically improve and sustain the implementation results. A case example is provided for demonstrating the proposed attempt
Comparative Study of Some Population-based Optimization Algorithms on Inverse Scattering of a Two-Dimensional Perfectly Conducting Cylinder in Slab Medium
[[abstract]]The application of four techniques for the shape reconstruction of a 2-D metallic cylinder buried in dielectric slab medium by measured the cattered fields outside is studied in the paper. The finite-difference time-domain (FDTD) technique is employed for electromagnetic analyses for both the forward and inverse scattering problems, while the shape reconstruction problem is transformed into optimization one during the course of inverse scattering. Then, four techniques including asynchronous particle swarm optimization (APSO), PSO, dynamic differential evolution (DDE) and self-adaptive DDE (SADDE) are applied to reconstruct the location and shape of the 2-Dmetallic cylinder for comparative purposes. The statistical performances of these algorithms are compared. The results show that SADDE outperforms PSO, APSO and DDE in terms of the ability of exploring the optima. However, these results are considered to be indicative and do not generally apply to all optimization problems in electromagnetics.[[incitationindex]]SCI[[incitationindex]]EI[[booktype]]紙本[[booktype]]電子
Serial increase of IL-12 response and human leukocyte antigen-DR expression in severe sepsis survivors
Introduction: Sepsis-induced immunosuppression may result in death. The mechanisms of immune suppression include loss of macrophage and monocyte expression of the major histocompatibility complex, increased anti-inflammatory cytokine expression and decreased expression of proinflammatory cytokines. In this study, we sought to determine the mechanisms of immune suppression in severe sepsis by repeated detection. Methods: We designed this prospective observational study to measure monocyte human leukocyte antigen (HLA)-DR expression, plasma cytokine levels and cytokine responses on days 1 and 7 in stimulated peripheral blood mononuclear cells (PBMCs) of healthy controls and patients with severe sepsis. Results: Of the 35 enrolled patients, 23 survived for 28 days and 12 died, 6 of whom died within 7 days. Plasma levels of IL-1 beta, IL-6, IL-10, IL-17, transforming growth factor (TGF)-beta 1 and TNF-alpha were higher, but plasma IL-12 level was lower in septic patients than those in controls. Day 1 plasma levels of IL-1 beta, IL-6, IL-10 and TGF-beta 1 in nonsurvivors were higher than those in survivors. Day 7 plasma IL-10 levels in nonsurvivors were higher than in survivors. IL-1 beta response was higher, but IL-12 and TNF-alpha responses were lower in septic patients than in controls. Day 1 IL-6 response was lower, but day 1 TGF-beta 1 response was higher in nonsurvivors than in survivors. Plasma IL-6 and IL-10 levels were decreased in survivors after 6 days. IL-6 response was decreased in survivors after 6 days, but IL-12 response was increased. Monocyte percentage was higher, but positive HLA-DR percentage in monocytes and mean fluorescence intensity (MFI) of HLA-DR were lower in septic patients than in controls. MFI of HLA-DR was increased in survivors after 6 days. Conclusions: Monocyte HLA-DR expression and IL-12 response from PBMCs are restored in patients who survive severe sepsis
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