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A fusion reactor is thought to offer the answer to the present global warming crisis. However, there were a few rooms that needed further examination. Helium research typically focuses on three key areas: 1) the transportation of helium from the plasma core as the D-T product; 2) the use of helium as the working gas for the removal of tritium, and 3) helium interaction with various plasma facing walls. The ITER plasma facing component is currently made entirely of metal, specifically beryllium and tungsten. Predicting the ITER plasma and the commercial stages of reactor development may depend on our ability to understand helium.

BackgroundThe objective of mass antimalarial drug administration (MDA) is to eliminate malaria rapidly by eliminating the asymptomatic malaria parasite reservoirs and interrupting transmission. In the Greater Mekong Subregion, where artemisinin-resistant Plasmodium falciparum is now widespread, MDA has been proposed as an elimination accelerator, but the contribution of asymptomatic infections to malaria transmission has been questioned. The impact of MDA on entomological indices has not been characterized previously.MethodsMDA was conducted in 4 villages in Kayin State (Myanmar). Malaria mosquito vectors were captured 3 months before, during, and 3 months after MDA, and their Plasmodium infections were detected by polymerase chain reaction (PCR) analysis. The relationship between the entomological inoculation rate, the malaria prevalence in humans determined by ultrasensitive PCR, and MDA was characterized by generalized estimating equation regression.ResultsAsymptomatic P. falciparum and Plasmodium vivax infections were cleared by MDA. The P. vivax entomological inoculation rate was reduced by 12.5-fold (95% confidence interval [CI], 1.6-100-fold), but the reservoir of asymptomatic P. vivax infections was reconstituted within 3 months, presumably because of relapses. This was coincident with a 5.3-fold (95% CI, 4.8-6.0-fold) increase in the vector infection rate.ConclusionAsymptomatic infections are a major source of malaria transmission in Southeast Asia.

Ripeness identification of fruits with short lifetime is important to benefit both the cultivators and consumers. Recently electronic noses (E-Noses) have become popular for fruit quality checkup for its sturdiness and repetitive usability without fatigue dissimilar to human experts. The primary components of an E-Nose are a data acquisition device, a sensor panel and a classification algorithm. Most sensors which are used for E-Noses are expensive. In addition a sensor panel with large number of sensors increases design complexity. Thus to find a minimal set of sensors with maximum relevant data classification efficiency is of vital importance. To analyze the classification efficiencies of different classification methods fruits, such as banana, mango, sapodilla, and pineapple are chosen. Two novel methods for finding a minimal set of sensors are proposed in this thesis. One is a principal component loading and mutual information based approach, and the other is a threshold based approach. With these methods minimal set of sensors are found which show more than 90% classification accuracy while classifying each of the four fruit types at three ripeness states. Once a sensor panel is designed and a data acquisition device chosen, a simple, fast, efficient classification method is required for classifying data of relevant training classes, and to reject any irrelevant data. At present to classify E- Nose data, k-nearest neighbor (k-NN), support vector machine (SVM) and multilayer perceptron neural network (MLPNN) classification algorithms are often applied. Due to open ended hyperplane based classification boundaries, these algorithms falsely classify extraneous odor data. For reducing false classification error and thereby improve correct rejection performance classification algorithms with hyperspheric boundary such as generalized regression neural network (GRNN) and radial basis function neural network (RBFNN) should be used. Simulation results show that GRNN has

ObjectivesTo assess the influence of body weight and missed doses on lopinavir pharmacokinetics with standard and increased doses of lopinavir/ritonavir melt extrusion tablets during late pregnancy.Patients and methodsLopinavir concentration data during the third trimester of pregnancy were pooled from clinical trials in Thailand (NCT00409591) and the USA (NCT00042289). A total of 154 HIV-infected pregnant women receiving either 400/100 mg (standard) or 600/150 mg (increased) twice daily had lopinavir plasma concentration data available. Population parameters were estimated using non-linear mixed-effects regression models. Monte Carlo simulations were performed to estimate the probability of achieving target lopinavir trough concentrations (>1.0 mg/L) with standard and increased doses of lopinavir/ritonavir during pregnancy.ResultsThe median (range) age, weight and gestational age were 28 years (18-43), 62 kg (45-123) and 33 weeks (29-38), respectively. Body weight influenced lopinavir oral clearance (CL/F) and volume of distribution (V/F). Population estimates of lopinavir CL/F and V/F were 6.21 L/h/70 kg and 52.6 L/70 kg, respectively. Based on simulations, the highest risk of subtherapeutic trough concentrations was for women weighing >100 kg using the standard dose (∼ 7%), while the risk was <2% with the 600/150 mg dose for women weighing 40-130 kg. After a missed dose, 61% of women have lopinavir concentrations below target prior to the next dose with the standard dose compared with 42% with the increased dose.ConclusionsStandard dosing provides adequate lopinavir trough concentrations for the majority of pregnant women but increased doses may be preferable for women weighing >100 kg and with a history of lopinavir/ritonavir use and/or adherence issues.

The objective of this study was to apply the QTL mapping by Markers-Assisted Selection approach for early selection on growth and latex yield in rubber breeding. The plant material consisted of 196 progenies derived from the F1 family RRIM 600 x PB 217. A genetic linkage map was built for this family with 229 SSR markers (microsatellites) and 198 AFLP markers. Phenotyping was carried out over a 6 years period on a field trial of 5 hectares, with around 2,400 trees measured individual. The two major QTLs were detected repeatedly. The QTL g16-6 was associated with latex yield near the position of marker a131. This QTL explained up to 66% of the phenotypic variance. It was also associated to other traits that were strongly correlated to production such as inorganic phosphorus and dry rubber content (latex diagnostic), as well as plugging index. This finding indicates the existence of one major gene (or a cluster of genes) located on linkage group g16 and involved in the intensity of metabolic activity of latex cell. A second important QTL associated with girth of the trunk (growth) was detected (QTL g3-60) at the position of marker a312. It explained up to 31% of the phenotypic variance. The discovery of the two major QTLs g3-60 and g16-6 suggest that two major genes act as limiting factors in the genetic determinism of the growth in girth during favorable condition and of rubber production in low-intensive tapping systems. These loci should become privileged targets for the identification of key-genes in rubber. The possible use of their neighboring markers for developing Markers-Assisted Selection (MAS) in the short run appears very reasonable. It should contribute to improve the accuracy of the first selection stage which is the weakest point of the rubber clonal selection scheme.

La Thaïlande est le premier producteur mondial de caoutchouc naturel qui représente 43 % de l'ensemble des élastomères (naturel + synthétique). Les variétés d'hévéa sont des clones hétérozygotes multipliés par greffage sur porte-greffes issus de graines. La première identification de QTLs chez l'hévéa a d'abord été réalisée au Cirad avec des marqueurs RFLP pour l'étude de la tolérance à la maladie sud-américaine des feuilles dans le cadre d'une coopération avec Michelin [1]. On est ensuite passé à l'utilisation de marqueurs SSR (microsatellites) pour la détection de QTLs associés à la croissance et à la production de latex de l'hévéa [2]. Deux QTLs importants ont été trouvés concernant la croissance et la production de latex. Leur utilisation en Sélection Assistée par Marqueurs, lors du screening initial très précoce des génotypes issus de la recombinaison par pollinisation manuelle, permettrait d'améliorer significativement l'efficacité de la sélection clonale.

The objective of this study was to analyse the genetic determinism of growth and latex production in rubber tree by a QTL approach. The plant material consisted of 196 progenies derived from the F1 family RRIM600 x PB217. A genetic linkage map was built for this family with 229 SSR markers (microsatellites) and 198 AFLP markers. Phenotyping was carried out over a 6-year period on a field trial of 5 hectares, with around 2400 trees measured individually. A high broad sense heritability was found for latex production, and a major QTL directly associated to production was discovered (Hbg16a131). This QTL explained from 32% to 59% of the genetic variance of the production traits. It was also associated to other traits that were strongly correlated to production such as inorganic phosphorus and dry rubber content (latex diagnostic), as well as plugging index. This finding indicates the existence of one major gene (or a cluster of genes) located on linkage group 16 and involved in the genetic determinism of latex production. A second important QTL associated to the girth of the trunk (growth) was detected (Hbg3a312). Depending on the age of the trees, it explained from 16% to 28% of the genetic variance of the girth. By contrast, no significant QTL was found for sucrose content of the latex, as estimated independently from the production, so suggesting that sucrose genetic determinism might not include any single gene having by itself some important effect. The application of one ethephon stimulation did not evidence any specific QTL. Those results pave the way for Markers-Assisted Selection (MAS) as applied to clonal selection in rubber. Genotyping the candidates to selection for the 2 QTLs with important effects should allow a much more accurate estimation of genetic values as soon as at the first selection stage.

Rubber breeding has long been based on conventional breeding and quantitative genetics based on phenotypic observations. Since recently, molecular genetic markers have brought new possibilities for characterizing genotypes, with view to identify cultivars, or their parents, to analyse genetic diversity, to establish relationships between agricultural traits and genetic factors (QTLs), and to identify genes of interest. In order to analyse the genetic bases of latex production, the cross RRIM600 x PB217 was created in Thailand for genotyping the progenies and building a genetic linkage map. The two parents were chosen for their contrasted physiological behaviour, as shown by the metabolic typology of cultivated rubber clones. Based on the double pseudo testcross strategy, two parental maps and a consensus map were built, with 334 progenies, 247 microsatellite markers, and 198 AFLP markers. The 18 linkage groups were assigned to the corresponding groups, equivalent to the 18 chromosomes of the Hevea haploid genome, of a Cirad Hevea genetic map used as reference. This new consensus map will be used together with field data for QTLs detection on heritable traits. Efforts will be priorily focussed on studying the physiological parameters of the latex diagnostic, in association with latex production.

For developing QTL detection based on the genetic linkage map of the cross RRIM600 x PB217, a clonal field trial was set in Thailand in June 2002. It will be studied until 2010 and targeted to the genetic analysis of the physiological parameters of the latex diagnostic which determine the metabolic typology of rubber clones. This trial, covering an area of 5 hectares, encompasses 196 progenies of the cross as well as the two parents, with every genotype represented by 5 to 16 replicated budded trees. The experimental design is an "alpha-plan" (incomplete block design): it was chosen for controlling the variation of the environment, for improving the levels of the heritabilities of the measured agricultural traits, and for improving the estimation of the genetic values of every genotype. Any trait with reasonably high heritability can be a candidate for possible QTL identification. So far, tapping has not begun yet, and QTL detection has not been attempted for any trait. In this communication, the characterization of traits related with growth, precocity of wintering, fruiting ability, and tolerance to water stress, is presented as a first characterization of the trial and of the genotypes. As growth is a complex trait, the associated heritabilities appear rather low, with a maximum of 0.36 for one height measurement. As the two parents are roughly equivalent in growth, variation among progenies within this family seems also rather low. This trial provides the rare opportunity to analyse the phenotypic variability displayed within a large size full-sib family of cultivated clones. It will also allow to select the best clones for recommendation to the planters, thereby combining short term and long term methodological and operational applications.

The primary objective of this thesis is to empirically investigate and offer behavioral explanations to two distinct areas of corporate decision-making: (i) mergers and acquisitions and (ii) corporate cash holdings. Based on the premise that it’s the retail investors who primarily trade during the overnight period, the first empirical study proposes absolute overnight returns (AOR) as a proxy for retail investor attention. AOR plays a vital role in the context of one of the largest and most significant corporate events - merger announcements. The study finds that AOR positively affects the acquirer abnormal returns and abnormal trading volumes. The short-term overreaction is corrected by price reversals in the post-announcement period. The set of results are strongest for bidders with low institutional ownership and bidders that are hard to value. The results further hold for the overreaction hypothesis related to stock swap deals while rejecting the notion that our proxy AOR captures investor sentiment. The second study empirically examines the role of CEO connectedness, the relative position of a CEO in the social network hierarchy on the corporate cash holdings. The study finds that cash holdings are on average higher firms for the firms managed by network-powerful CEOs. Lending support to the CEO power hypothesis the positive association is stronger for firm-year observations with investment spikes, greater financial constraint, weaker corporate governance, low institutional monitoring, and raising cash regimes. The results are robust to a series of tests and alternative explanations. The third study empirically examines the role of CEO connectedness on the value of cash and finds that cash holding is on average less valuable for the firms managed by network-powerful CEOs. In economic terms, a network-powerful CEO on board is associated with a value loss of 44 cents in every $1.00 of cash holdings. Providing support to the CEO power hypothesis the negative assoc

The primary objective of this thesis is to empirically investigate and offer behavioral explanations to two distinct areas of corporate decision-making: (i) mergers and acquisitions and (ii) corporate cash holdings. Based on the premise that it’s the retail investors who primarily trade during the overnight period, the first empirical study proposes absolute overnight returns (AOR) as a proxy for retail investor attention. AOR plays a vital role in the context of one of the largest and most significant corporate events - merger announcements. The study finds that AOR positively affects the acquirer abnormal returns and abnormal trading volumes. The short-term overreaction is corrected by price reversals in the post-announcement period. The set of results are strongest for bidders with low institutional ownership and bidders that are hard to value. The results further hold for the overreaction hypothesis related to stock swap deals while rejecting the notion that our proxy AOR captures investor sentiment. The second study empirically examines the role of CEO connectedness, the relative position of a CEO in the social network hierarchy on the corporate cash holdings. The study finds that cash holdings are on average higher firms for the firms managed by network-powerful CEOs. Lending support to the CEO power hypothesis the positive association is stronger for firm-year observations with investment spikes, greater financial constraint, weaker corporate governance, low institutional monitoring, and raising cash regimes. The results are robust to a series of tests and alternative explanations. The third study empirically examines the role of CEO connectedness on the value of cash and finds that cash holding is on average less valuable for the firms managed by network-powerful CEOs. In economic terms, a network-powerful CEO on board is associated with a value loss of 44 cents in every $1.00 of cash holdings. Providing support to the CEO power hypothesis the negative assoc

The primary objective of this thesis is to empirically investigate and offer behavioral explanations to two distinct areas of corporate decision-making: (i) mergers and acquisitions and (ii) corporate cash holdings. Based on the premise that it’s the retail investors who primarily trade during the overnight period, the first empirical study proposes absolute overnight returns (AOR) as a proxy for retail investor attention. AOR plays a vital role in the context of one of the largest and most significant corporate events - merger announcements. The study finds that AOR positively affects the acquirer abnormal returns and abnormal trading volumes. The short-term overreaction is corrected by price reversals in the post-announcement period. The set of results are strongest for bidders with low institutional ownership and bidders that are hard to value. The results further hold for the overreaction hypothesis related to stock swap deals while rejecting the notion that our proxy AOR captures investor sentiment. The second study empirically examines the role of CEO connectedness, the relative position of a CEO in the social network hierarchy on the corporate cash holdings. The study finds that cash holdings are on average higher firms for the firms managed by network-powerful CEOs. Lending support to the CEO power hypothesis the positive association is stronger for firm-year observations with investment spikes, greater financial constraint, weaker corporate governance, low institutional monitoring, and raising cash regimes. The results are robust to a series of tests and alternative explanations. The third study empirically examines the role of CEO connectedness on the value of cash and finds that cash holding is on average less valuable for the firms managed by network-powerful CEOs. In economic terms, a network-powerful CEO on board is associated with a value loss of 44 cents in every $1.00 of cash holdings. Providing support to the CEO power hypothesis the negative assoc

The primary objective of this thesis is to empirically investigate and offer behavioral explanations to two distinct areas of corporate decision-making: (i) mergers and acquisitions and (ii) corporate cash holdings. Based on the premise that it’s the retail investors who primarily trade during the overnight period, the first empirical study proposes absolute overnight returns (AOR) as a proxy for retail investor attention. AOR plays a vital role in the context of one of the largest and most significant corporate events - merger announcements. The study finds that AOR positively affects the acquirer abnormal returns and abnormal trading volumes. The short-term overreaction is corrected by price reversals in the post-announcement period. The set of results are strongest for bidders with low institutional ownership and bidders that are hard to value. The results further hold for the overreaction hypothesis related to stock swap deals while rejecting the notion that our proxy AOR captures investor sentiment. The second study empirically examines the role of CEO connectedness, the relative position of a CEO in the social network hierarchy on the corporate cash holdings. The study finds that cash holdings are on average higher firms for the firms managed by network-powerful CEOs. Lending support to the CEO power hypothesis the positive association is stronger for firm-year observations with investment spikes, greater financial constraint, weaker corporate governance, low institutional monitoring, and raising cash regimes. The results are robust to a series of tests and alternative explanations. The third study empirically examines the role of CEO connectedness on the value of cash and finds that cash holding is on average less valuable for the firms managed by network-powerful CEOs. In economic terms, a network-powerful CEO on board is associated with a value loss of 44 cents in every $1.00 of cash holdings. Providing support to the CEO power hypothesis the negative assoc