Positrons sources and related activities for Future Linear Collider at LAL Orsay Laboratory

In the context of the positrons sources studies for the Future Linear Collider, the Accelerator Department at LAL Orsay is involved since several years in different activities both experiments and simulations.Comment: LCWS201

Case Reports1. A Late Presentation of Loeys-Dietz Syndrome: Beware of TGFβ Receptor Mutations in Benign Joint Hypermobility

Background: Thoracic aortic aneurysms (TAA) and dissections are not uncommon causes of sudden death in young adults. Loeys-Dietz syndrome (LDS) is a rare, recently described, autosomal dominant, connective tissue disease characterized by aggressive arterial aneurysms, resulting from mutations in the transforming growth factor beta (TGFβ) receptor genes TGFBR1 and TGFBR2. Mean age at death is 26.1 years, most often due to aortic dissection. We report an unusually late presentation of LDS, diagnosed following elective surgery in a female with a long history of joint hypermobility. Methods: A 51-year-old Caucasian lady complained of chest pain and headache following a dural leak from spinal anaesthesia for an elective ankle arthroscopy. CT scan and echocardiography demonstrated a dilated aortic root and significant aortic regurgitation. MRA demonstrated aortic tortuosity, an infrarenal aortic aneurysm and aneurysms in the left renal and right internal mammary arteries. She underwent aortic root repair and aortic valve replacement. She had a background of long-standing joint pains secondary to hypermobility, easy bruising, unusual fracture susceptibility and mild bronchiectasis. She had one healthy child age 32, after which she suffered a uterine prolapse. Examination revealed mild Marfanoid features. Uvula, skin and ophthalmological examination was normal. Results: Fibrillin-1 testing for Marfan syndrome (MFS) was negative. Detection of a c.1270G > C (p.Gly424Arg) TGFBR2 mutation confirmed the diagnosis of LDS. Losartan was started for vascular protection. Conclusions: LDS is a severe inherited vasculopathy that usually presents in childhood. It is characterized by aortic root dilatation and ascending aneurysms. There is a higher risk of aortic dissection compared with MFS. Clinical features overlap with MFS and Ehlers Danlos syndrome Type IV, but differentiating dysmorphogenic features include ocular hypertelorism, bifid uvula and cleft palate. Echocardiography and MRA or CT scanning from head to pelvis is recommended to establish the extent of vascular involvement. Management involves early surgical intervention, including early valve-sparing aortic root replacement, genetic counselling and close monitoring in pregnancy. Despite being caused by loss of function mutations in either TGFβ receptor, paradoxical activation of TGFβ signalling is seen, suggesting that TGFβ antagonism may confer disease modifying effects similar to those observed in MFS. TGFβ antagonism can be achieved with angiotensin antagonists, such as Losartan, which is able to delay aortic aneurysm development in preclinical models and in patients with MFS. Our case emphasizes the importance of timely recognition of vasculopathy syndromes in patients with hypermobility and the need for early surgical intervention. It also highlights their heterogeneity and the potential for late presentation. Disclosures: The authors have declared no conflicts of interes

Research and Design of a Routing Protocol in Large-Scale Wireless Sensor Networks

无线传感器网络，作为全球未来十大技术之一，集成了传感器技术、嵌入式计算技术、分布式信息处理和自组织网技术，可实时感知、采集、处理、传输网络分布区域内的各种信息数据，在军事国防、生物医疗、环境监测、抢险救灾、防恐反恐、危险区域远程控制等领域具有十分广阔的应用前景。 本文研究分析了无线传感器网络的已有路由协议，并针对大规模的无线传感器网络设计了一种树状路由协议，它根据节点地址信息来形成路由，从而简化了复杂繁冗的路由表查找和维护，节省了不必要的开销，提高了路由效率，实现了快速有效的数据传输。 为支持此路由协议本文提出了一种自适应动态地址分配算——ADAR（AdaptiveDynamicAddre...As one of the ten high technologies in the future, wireless sensor network, which is the integration of micro-sensors, embedded computing, modern network and Ad Hoc technologies, can apperceive, collect, process and transmit various information data within the region. It can be used in military defense, biomedical, environmental monitoring, disaster relief, counter-terrorism, remote control of haz...学位：工学硕士院系专业：信息科学与技术学院通信工程系_通信与信息系统学号：2332007115216

Mesures des neutrinos de réacteurs nucléaires dans l'expérience BOREXINO

The main goal of the Borexino experiment is to measure in real time the solar neutrino flux from the beryllium line at 862 keV. Beyond this pioneer low energy neutrino detection, Borexino will be able to measure solar neutrinos above the MeV, (8B neutrinos and pep neutrinos), nuclear reactor neutrinos (with an average energy of 3 MeV) and the supernovæ neutrinos (their spectrum goes up to some ten MeV). In this work I mainly focus on the study of the nuclear reactors neutrinos. This field has recently been enriched by the results of the KamLAND experiment, which have greatly improved the determination of the neutrino oscillation parameters. In order to measure these events which are above the MeV, the Borexino collaboration entrusted the PCC group, Collège de France, with the tasks of developing a fast digitalization system running at 400MHz : the FADC cards. The PCC group designed the FADC cards and completed them at the beginning of 2002. The first cards which were introduced in the main electronic acquisition allowed us to control their functioning and that of the acquisition software. FADC cards were also installed in the Borexino prototype, CTF. The data are analysed in order to determine a limit to the expected background noise of Borexino in measuring the nuclear reactor neutrinos.L'objectif principal de l'expérience Borexino est "la détection en temps réel" des neutrinos solaires de la raie du béryllium à 862keV. Outre cette mesure pionnière dans le domaine des neutrinos de basse énergie, Borexino pourra mesurer les neutrinos solaires au-dessus du MeV (neutrinos du 8B et neutrinos pep), les neutrinos de réacteurs nucléaires (d'énergie moyenne d'environ 3 MeV) et les neutrinos de supernovae (dont le spectre en énergie s'étend jusqu'à quelques dizaines de MeV). Le présent travail est consacré principalement à l'étude des neutrinos de réacteurs nucléaires. Ce domaine a été récemment enrichi par les résultats de KamLAND, qui ont grandement amélioré la détermination des paramètres d'oscillations des neutrinos. Dans l'objectif de mesurer ces événements au dessus du MeV, la collaboration Borexino a confié au groupe du PCC, Collège de France, le développement d'un système de numérisation rapide fonctionnant à 400 MHz: les cartes FADC. Elles ont été conçues au laboratoire et nous les avons finalisées au début de l'année 2002. Les premières cartes implantées dans l'électronique d'acquisition de Borexino nous ont permis de contrôler leurs fonctionnements et celui du programme d'acquisition. Elles ont été également installées sur le prototype de Borexino, CTF. Les données correspondantes sont analysées en vue de mettre une limite sur le bruit de fond attendu dans Borexino pour la mesure des neutrinos de réacteurs nucléaires