Spatial network sampling in small area estimation

The spatial distribution of a population represents an important in sampling designs where that use the network of the contiguities between units as auxiliary information in the frame. Its use is increased in the last decades as the GIS and GPS technologies made more and more cheap to add information regarding the exact or estimated position for each record in the frame. These data may represent a source of auxiliaries that can be helpful to design effective sampling strategies, which, assuming that the observed phenomenon is related with the spatial features of the population, could gather a considerable gain in their efficiency by a proper use of this particular information. This assumption is particularly relevant if we are dealing with not planned geographical domains or, in other terms, if we want that the design will be efficient for a future use within a small area estimation context. A method for selecting samples from a spatial finite population that are well spread over the population in every dimension should guarantee that the variability of the expected sampling ratio should be smaller than that obtained by using a simple random sampling. Some algorithms of sample selection are presented such that a set of units with higher within distance will be selected with higher probability than a set of nearby units. Some examples on real data show that the RMSE of the EBLUP estimates applied to samples selected with these network methods are lower than those obtained by using a classical solution as the Generalized Random Tessellation Stratified (GRTS). The proposed algorithm, even if in its nature it is computationally intensive, seems to be a feasible solution even when dealing with frames relevant to large finite network populations

Influence of eNOS Gene Polymorphisms on Carotid Atherosclerosis

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Comparison between Aorto-bifemoral Bypass and Aorto-iliac Kissing Stent in Patients with Complex Aorto-iliac Obstructive Disease

Introduction: To retrospectively compare early and late results of aorto-bifemoral bypass and endovascular recanalization with the kissing stent technique in the management of TASC II C and D lesions in the aorto-iliac district in a multicentre study. Methods: From January 2006 to December 2013, 293 open and endovascular interventions for TASC-II class C and D aorto-iliac obstructive lesions were performed at three Italian teaching hospitals. In 210 patients the intervention was performed for aortic and bilateral iliac involvement: an aorto-bifemoral bypass was performed in 82 patients (Group 1) while in the remaining 128 an endovascular recanalization with the kissing stent technique (Group 2). Early results in the two groups were compared with \u3c72 test. Follow up results were analyzed with Kaplan-Meyer curves and compared with log rank test. Results: There were no differences between the two groups in terms of demographic data, comorbidities, or risk factors for atherosclerosis, except for a higher percentage of females and of diabetic patients in group 2. Critical limb ischemia was present in 29 patients in group 1 (35.5%) and in 31 patients in group 2 (24%, p = 0.07). Technical success in group 2 was 98.5%; two patients required immediate conversion to open surgery for iliac rupture. There was one peri-operative death in group 1 (mortality rate 1.2%, p = 0.2 in comparison with group 2). Four peri-operative thromboses occurred; two in group 1 and two in group 2 (in one case requiring conversion to open surgical intervention) and no amputations at 30 days were recorded. Post-operative local and systemic complications occurred in 20 patients in group 1 (24%) and in 13 patients in group 2 (10% p = 0.006). Mean duration of follow up was 39 months (range 1 \u2013108 months). Survival rates at 6 years were 65% (SE 0.07) in group 1 and 82% (SE 0.05) in group 2 (p = 0.07). At the same time interval, primary, assisted primary and secondary patency rates were similar; re-intervention rates were 6% in group 1 (SE 0.05) and 11% in group 2 (SE 0.04; p = 0.2). Conclusion: Endovascular repair of complex aorto-iliac lesions with the kissing stent technique, in the multicentre experience, provided similar satisfactory early and late results to those obtained with open surgery, however with a lower rate of peri-operative complications and a trend towards better long-term survival

Eating Disorders

Anorexia and bulimia are diseases known since ancient times, but in recent years their frequency has been continuously increasing in most industrialized countries. The etiology of these disorders can be traced back to the interaction between genetic predisposition, childhood experiences, and cultural pressures. As regards the course, a certain tendency to chronicity can be observed, and in extreme cases, they can cause death. According to the diagnostic classification of the DSM-5, eating disorders include anorexia nervosa, bulimia nervosa, binge eating disorder (which, compared to DSM-IV, becomes a diagnostic category in its own right), and other specified feeding and eating disorders (OSFED). Both anorexia and bulimia cause potentially serious medical complications. To maximize the chances of good outcomes a multidisciplinary intervention is necessary with staff including professionally heterogeneous figures: a psychiatrist, a psychologist, and a nutritionist. Therapeutic success for these patients is limited. Eating disorders require, among psychiatric disorders, the greatest possible collaboration between different professional figures with different specializations