Proof-of-Principle Experiment for FEL-Based Coherent Electron Cooling,”

Abstract Coherent electron cooling (CEC) has a potential to significantly boost luminosity of high-energy, highintensity hadron-hadron and electron-hadron colliders. In a CEC system, a hadron beam interacts with a cooling electron beam. A perturbation of the electron density caused by ions is amplified and fed back to the ions to reduce the energy spread and the emittance of the ion beam. To demonstrate the feasibility of CEC we propose a proof-of-principle experiment at RHIC using SRF linac. In this paper, we describe the setup for CeC installed into one of RHIC's interaction regions. We present results of analytical estimates and results of initial simulations of cooling a gold-ion beam at 40 GeV/u energy via CeC

Detectable Trypanosoma cruzi parasitemia during pregnancy and delivery as a risk factor for congenital Chagas disease : short report

Vector control has led to a drastic decrease in the prevalence of acquired Chagas disease in Latin America thus redirecting attention to congenital Chagas disease We report results of a longitudinal study of 359 pregnant women in Yacuiba in southern Bolivia, of whom 147 (40 9%) were infected with Trypanosoma cruzi, to evaluate the relation ship between the patency period of the parasitemia and the risk of congenital infection Maternal infection was assessed by using T cruzi-specific serologic tests and parasitemia in mothers and newborns was diagnosed by using microscopic examination of blood in heparinized microhematocrit tubes Parasitemia was present in 28 6% of the infected women Its prevalence increased during the third trimester then decreased at delivery The likelihood of congenital infection was significantly correlated with the parasite density in the mother s blood The risk of transmission increased during the third trimester of pregnancy and could explain premature births or low weight newborns for infected mother

First experience with He conditioning of an SRF photoinjector

The recent achievements in the performance of superconducting RF (SRF) photoinjectors have opened a new era in the development of the reliable high-brightness CW electron sources. While the SRF guns become one of the most promising technologies, the compatibility of SRF environment with the complex photocathodes remains on the forefront of the modern accelerator science. The SRF cavities operate at cryogenic temperatures providing the ultra-high vacuum (UHV) environment highly beneficial for the photocathode performance. However, the necessity to keep the photocathodes at room temperature while being surrounded by the cavity walls that are kept at cryogenic temperatures creates an additional complexity for the SRF gun design and operation. The complex and volatile chemical compounds used for photocathodes have a high chance of contaminating the surfaces of an SRF cavity. When deposited, such compounds could create centers for cold electron emission which degrade performance of the SRF guns. Such a circumstance would require development of the in-situ processing techniques for restoring the SRF cavity performance. This paper presents the results of the successful implementation and application of the He conditioning method for cavity restoration using the existing SRF photoinjector at Brookhaven National Laboratory (BNL). The method has proven to be extremely effective and resulted in a dramatic improvement of the BNL gun performance

Molecular weight sensing properties of ionic liquid-polymer composite films: Theory and experiment

Ionic liquids (ILs) are rapidly emerging as important coating materials for highly sensitive chemical sensing devices. In this regard, we have previously demonstrated that a quartz crystal microbalance (QCM) coated with a binary mixture of an IL and cellulose acetate can be employed for detection and molecular weight estimation of organic vapors (J. Mater. Chem. 2012, 22, 13732). Herein, we report follow-up studies aimed at formulating the theoretical basis for our previously observed relationship between molecular weight and changes in the QCM parameters. In the current work, we have investigated the vapor sensing characteristics of a series of binary blends of ILs and polymers over a wider concentration range of analytes, and a quadratic equation for estimating the approximate molecular weight of an organic vapor is proposed. Additionally, the frequency (f) and dissipation factor (D) at multiple harmonics were measured by use of a quartz crystal microbalance with dissipation monitoring (QCM-D). These QCM-D data were then analyzed by fitting to various models. It is observed that the behavior of these films can be best described by use of the Maxwell viscoelastic model. In light of these observations, a plausible explanation for the correlation between the molecular weight of absorbed vapors and the QCM parameters is presented. Our previous findings appear to be a special case of this more general observation. Overall, these results underscore the true potential of IL-based composite materials for discrimination and molecular weight estimation of a broad range of chemical vapors. This journal is © the Partner Organisations 2014

Maladies transmissibles et environnement : table-ronde

The enhancement of the agricultural space, the developpement of urbanized areas are as many factors which are modifying the epidemiology of many pathologies. These processes are particularly important in developing countries. Unfortunately, even if the health consequences of the environnemental changes become present preoccupation of imported large development programs, they are considered most of the time as marginal when these modification processes occur within "traditional" social groups. For now, the very few important development projects in Madagascar especially found in the coast areas. Most of the rural population live poorly with real difficulties. But the health consequences of the processes of environment management are taken into account only by the existing development projects. Nevertheless the stakes to work out public health strategies are considerable. The discussion is focused on a geographical and medical survey which was conducted during July and August 1995 in 61 villages located in the highlands and the middle west of Madagascar. The results obtained during that survey revealed the main health differences in the study area. In regard to these spatial health variations, it is now possible to begin to explore the link between health and environment. (Résumé d'auteur

Maladies transmissibles et environnement : table-ronde

The enhancement of the agricultural space, the developpement of urbanized areas are as many factors which are modifying the epidemiology of many pathologies. These processes are particularly important in developing countries. Unfortunately, even if the health consequences of the environnemental changes become present preoccupation of imported large development programs, they are considered most of the time as marginal when these modification processes occur within "traditional" social groups. For now, the very few important development projects in Madagascar especially found in the coast areas. Most of the rural population live poorly with real difficulties. But the health consequences of the processes of environment management are taken into account only by the existing development projects. Nevertheless the stakes to work out public health strategies are considerable. The discussion is focused on a geographical and medical survey which was conducted during July and August 1995 in 61 villages located in the highlands and the middle west of Madagascar. The results obtained during that survey revealed the main health differences in the study area. In regard to these spatial health variations, it is now possible to begin to explore the link between health and environment. (Résumé d'auteur