Mise au point et validation d'un fantôme spécifique pour asssurer le suivi des mesures quantitatives en tomographie par émission de positons.

L'index de consommation du glucose, SUV pour standardized uptake value, est largement utilisé en tomographie par émission de positons (TEP) pour quantifier la concentration relative de [18F]2-fluoro-2-désoxy-D-glucose (18F-FDG) dans les tissus. Cependant, cet indice dépend de nombreux facteurs méthodologiques et biologiques et son utilisation fait débat. Il est donc primordial d'instaurer un contrôle qualité régulier permettant d'assurer la stabilité de la mesure des indices quantitatifs. Dans cette optique, un fantôme spécifique avec inserts cylindriques de différentes tailles a été développé. L'objectif de cette étude est de montrer la sensibilité et l'intérêt de ce fantôme. Méthodes. - La sensibilité du fantôme a été étudiée à travers la mesure des SUV et des coefficients de recouvrement (RC). Plusieurs méthodes de mesure ont été utilisées. Les données ont été reconstruites en utilisant les algorithmes de routine clinique. Nous avons étudié la variation des RC en fonction de la taille des cylindres et le changement relatif de fixation, en utilisant des activités différentes. Le fantôme a ensuite été testé sur l'appareil d'un autre centre. Résultats. - Pour toutes les méthodes de mesure, une forte variation des RC avec la taille des cylindres, de l'ordre de 50 %, a été obtenue. Ce fantôme a également permis de mesurer un changement relatif de fixation qui s'est révélé être indépendant de la méthode de mesure. Malgré un étalonnage des deux systèmes TEP/TDM, des différences de quantification d'environ 20 % ont subsisté. Conclusion. - Les résultats obtenus montrent l'intérêt de ce fantôme dans le cadre du suivi des mesures quantitatives.

Restoration of a lost geological reference point: the loggingstone of Pedralta (Girona, Spain)

The Pedralta is a loggingstone formed of monzonitic leucogranites, which has a volume of about 38 m3 and weighs 101 tons. After its fall in December 1996, a public subscription was opened to meet the expenses of the restoration work, which was completed in May 1999

Immigration policy with partisan parties

This paper analyzes the political economy of immigration when the salient electoralissue is the level of immigrants and the relevant immigration policy is the expenditurein immigration control. We consider that immigration affects voters? welfarethrough economic and non economic factors. We model political competition `a laWittman with the ideology of parties endogenously determined at equilibrium. Atequilibrium, parties propose different levels of immigration, located to the left and tothe right of the median voter?s ideal point, and combine skilled and unskilled workersamong their constituencies. Numerical simulations provide the levels of immigrationproposed by the two parties and the composition of parties? constituencies as we varythe efficacy of immigration control and the intensity of immigration aversion.

The OCBI Tipping Point, July 10, 2007, Vol. 1

This is the weekly e-Newsletter called “The OCBI Tipping Point.” We hope that you find it very informative as we explore all possibilities to keep our constituency and the general public informed about all matters that affect Blacks in the state of Iowa.

The OCBI Tipping Point, August 7, 2007, Vol. 2

This is the weekly e-Newsletter called “The OCBI Tipping Point.” We hope that you find it very informative as we explore all possibilities to keep our constituency and the general public informed about all matters that affect Blacks in the state of Iowa.

The OCBI Tipping Point, August 23, 2007, Vol. 1, no.3

This is the weekly e-Newsletter called “The OCBI Tipping Point.” We hope that you find it very informative as we explore all possibilities to keep our constituency and the general public informed about all matters that affect Blacks in the state of Iowa.

The OCBI Tipping Point, August 29, 2007, Vol. 1, no.4

This is the weekly e-Newsletter called “The OCBI Tipping Point.” We hope that you find it very informative as we explore all possibilities to keep our constituency and the general public informed about all matters that affect Blacks in the state of Iowa.

The OCBI Tipping Point, December 7, 2007, Vol. 1, no.5

This is the weekly e-Newsletter called “The OCBI Tipping Point.” We hope that you find it very informative as we explore all possibilities to keep our constituency and the general public informed about all matters that affect Blacks in the state of Iowa.

Low density polyethylene (LDPE) passive samplers for the investigation of polychlorinated biphenyl (PCB) point sources in rivers

This study aims to provide a passive sampling approach which can be routinely used to investigate polychlorinated biphenyl (PCB) sources in rivers. The approach consists of deploying low density polyethylene (LDPE) strips downstream and upstream of potential PCB sources as well as in their water discharges. Concentrations of indicator PCBs (iPCBs) absorbed in samplers (Cs) from upstream and downstream sites are compared with each other to reveal increases of PCB levels. Cs measured in water discharges are used to determine if released amounts of PCBs are compatible with increases revealed in the river. As water velocity can greatly vary along a river stretch and influences the uptake at each site in a different way, differences in velocity have to be taken into account to correctly interpret Cs. LDPE strips were exposed to velocities between 1.6 and 37 cm s−1 using a channel system built in the field. Relationships between velocity and Cs were established for each iPCB to determine the expected change in Cs due to velocity variations. For PCBs 28 and 52, this change does not exceed a factor 2 for velocity variations in the range from 1.6 to 100 cm s−1 (extrapolated data above 37 cm s−1). For PCBs 101, 138, 153 and 180, this change only exceeds a factor 2 in the case of large velocity variations. The approach was applied in the Swiss river Venoge to first conduct a primary investigation of potential PCB sources and then conduct thorough investigations of two suspected sources.

Clúster de alta disponibilidad y balanceo de carga sobre un servidor web

El present projecte neix degut a la necessitat de dotar a un pàgina web de una estructura sòlida així com una millor resposta als usuaris. El projecte es pot fraccionar en 2 blocs, els quals son: -La creació de un clúster de alta disponibilitat de manera que assegurem que en cas de fallida de un dels servidors físics la web seguirà sent visible per al públic. -La creació de un clúster de balanceig de càrrega que s’encarrega de redirigir les peticions per a veure la web al node del clúster que sigui més ociós en aquell.

p27 and Skp2 immunoreactivity and its clinical significance with endocrine and chemo-endocrine treatments in node-negative early breast cancer.

BACKGROUND: Low p27 and high Skp2 immunoreactivity are associated with a poor prognosis and other poor prognostic features including resistant phenotypes and antiestrogen drug resistance. We investigated these proteins in two International Breast Cancer Study Group trials studying node-negative early breast cancer. PATIENTS AND METHODS: Trial VIII compared chemotherapy followed by goserelin with either modality alone in premenopausal patients. Trial IX compared chemotherapy followed by tamoxifen with tamoxifen alone in postmenopausal patients. Central Pathology Office assessed p27 and Skp2 expression in the primary tumor by immunohistochemistry among 1631 (60%) trial patients. RESULTS: p27 and Skp2 were inversely related; 13% of tumors expressed low p27 and high Skp2. Low p27 and high Skp2 were associated with unfavorable prognostic factors including larger size and higher grade tumors, absence of estrogen receptor and progesterone receptor, human epidermal growth factor receptor 2 overexpression and high Ki-67 (each P < 0.05). Low p27 and high Skp2 were not associated with disease-free survival (P = 0.42 and P = 0.48, respectively). The relative effects of chemo-endocrine versus endocrine therapy were similar regardless of p27 or Skp2. CONCLUSIONS: We confirm the association of low p27 and high Skp2 with other poor prognostic features, but found no predictive or prognostic value, and therefore do not recommend routine determination of p27 and Skp2 for node-negative breast cancer.