Analysis of tapered front-coupling X-ray waveguides.

The coupling and propagation of electromagnetic waves through planar X-ray waveguides (WG) with vacuum gap and Si claddings are analyzed in detail, starting from the source and ending at the detector. The general case of linearly tapered WGs (i.e. with the entrance aperture different from the exit one) is considered. Different kinds of sources, i.e. synchrotron radiation and laboratory desk-top sources, have been considered, with the former providing a fully coherent incoming beam and the latter partially coherent beams. It is demonstrated that useful information about the parameters of the WG can be derived, comparing experimental results with computer simulation based on analytical solutions of the Helmholtz equation which take into account the amplitude and phase matching between the standing waves created in front of the WG, and the resonance modes propagating into the WG

Framework para la predicción de generación y consumo eléctrico a corto plazo aplicando modelos combinados de línea base y regresión

La predicción de generación y consumo eléctrico a corto plazo supone una herramienta de enorme interés dentro del sistema eléctrico, donde la presencia de fuentes de generación renovable y distribuida está en constante crecimiento. Específicamente, este tipo de predicción es esencial para la gestión energética en edificios, industrias y microgrids para optimizar la operación de sus recursos energéticos bajo diferentes criterios. Teniendo esto en cuenta, se ha propuesto un framework completo para la predicción de generación y consumo en smart grids y microgrids. Concretamente, este framework se utiliza para comparar un conjunto de técnicas basadas en reglas y aprendizaje automático (machine learning) para realizar la predicción de variables eléctricas del día siguiente. Además, se presenta un enfoque novedoso que incluye el uso de modelos de línea base como entradas para los modelos de machine learning. Los resultados obtenidos indican que este enfoque mejora significativamente la predicción frente al resto de técnicas comparadas, logrando una mejora de hasta el 62% con respecto al método Naive. Estos resultados se han obtenido al aplicar la metodología propuesta para predecir cinco variables de potencia de generación y consumo eléctrico del Campus de Savona de la Universidad de Génova en Italia.Ministerio de Ciencia, Innovación y Universidades de España mediante el proyecto “Bigdata Analitycs e Instrumentación Cyberfísica para Soporte de Operaciones de Distribución en la Smart Grid” RTI2018-094917-B-I00Ministerio de Educación y Formación Profesional de España FPU16/0352

Spatial Guilds in the Serengeti Food Web Revealed by a Bayesian Group Model

Food webs, networks of feeding relationships among organisms, provide fundamental insights into mechanisms that determine ecosystem stability and persistence. Despite long-standing interest in the compartmental structure of food webs, past network analyses of food webs have been constrained by a standard definition of compartments, or modules, that requires many links within compartments and few links between them. Empirical analyses have been further limited by low-resolution data for primary producers. In this paper, we present a Bayesian computational method for identifying group structure in food webs using a flexible definition of a group that can describe both functional roles and standard compartments. The Serengeti ecosystem provides an opportunity to examine structure in a newly compiled food web that includes species-level resolution among plants, allowing us to address whether groups in the food web correspond to tightly-connected compartments or functional groups, and whether network structure reflects spatial or trophic organization, or a combination of the two. We have compiled the major mammalian and plant components of the Serengeti food web from published literature, and we infer its group structure using our method. We find that network structure corresponds to spatially distinct plant groups coupled at higher trophic levels by groups of herbivores, which are in turn coupled by carnivore groups. Thus the group structure of the Serengeti web represents a mixture of trophic guild structure and spatial patterns, in contrast to the standard compartments typically identified in ecological networks. From data consisting only of nodes and links, the group structure that emerges supports recent ideas on spatial coupling and energy channels in ecosystems that have been proposed as important for persistence.Comment: 28 pages, 6 figures (+ 3 supporting), 2 tables (+ 4 supporting

Demonstration in human cadavers of feasibility of ileoproctostomy performed entirely through a transanal route

Innovative surgical techniques are frequently developed in animal models before of trials in surgical patients. However, these experimental approaches do not permit a perfect evaluation of feasibility due to obvious anatomical differences between humans and animals. The Body Donation Program of the University of Padua has recently developed studies of feasibility on human cadavers of new surgical approaches. Natural Orifice Transluminal Endoscopic Surgery (NOTES) is an innovative kinf of surgery which utilizes a flexible endoscope to enter the abdominal, pelvic or thoracic cavities through the body’s natural orifices and then through an internal incision. Skin incisions are thus unnecessary and, as a consequence, tissue trauma, postoperative pain, and incision-related complications are minimized and less anaesthesia is required. The aim of the present study was to verify in human cadavers the technical feasibility of a new NOTES technique, i.e., ileoproctostomy performed entirely through a transanal access. This surgical procedure was previously performed only in a porcine model. The procedure was carried out in three human cadavers (two males and a female). One cadaver was fresh. The other cadavers were fixed through infusion of Thiel’s solution through the larger arteries. A Transanal Endoscopic Microsurgery (TEM) device and endoscopic instruments were utilized. The study demonstrated that ileoproctostomy through a transanal access is technically feasible in humans. The principal steps of the procedure were: placement of the TEM device; rectal perforation above the peritoneal reflection; peritoneoscopy using a standard gastroscope; grasping the small bowel with retrieval forceps and pulling it through the rectal hole; suturing the ileum and the rectum together with two semi-circular continuous sutures utilizing the TEM device; opening the ileal loop from the rectal side followed by endoscopic exploration. Although still at an experimental stage, ileoproctostomy through a transanal access is technically feasible in humans. In planning new procedures, a fundamental step is represented by feasibility tests on donated corpse

Characterization of novel autologous leukocyte fibrin platelet membranes for tissue engineering applications

Autologous hemocomponents have recently emerged as potential biologic tools for regenerative purpose, consisting mainly of platelet concentrates which locally release growth factors (GFs) to enhance the tissue healing process. Despite two decades of clinical studies, the therapeutic efficacy of platelet concentrates is still controversial. This work represents a first characterization of a novel autologous leukocyte fibrin platelet membrane (LFPm), which is prepared by the Department of Immunohematology of Belluno Hospital according to a well standardized protocol. The quantification of their specific content showed that LFPms are enriched not only with platelets, but also with monocytes/macrophages, fibrinogen and CD34+ cells. Mechanical properties of LFPms were investigated by tensile tests, revealing that the specific elasticity of membranes was maintained over time. Furthermore, the release kinetics of Platelet Derived Growth Factor, Vascular Endothelial Growth Factor, Tumor Necrosis Factor alpha and Interleukin-10 was assessed by ELISA, demonstrating that LFPms act as GF delivery systems which sustain the local release of bioactive molecules. For in vitro biodegradation analysis, LFPm samples were incubated into PBS solution for 4, 7, 14, 21 days. SEM micrographs showed a progressive loss in cellular elements associated to a simultaneous exposure of the fibrin scaffold, also confirmed by histological and immunohistochemical investigations. In parallel, LFPm disks were implanted into a subcutaneous dorsal pouch of healthy nude rats and explanted after 4, 7, 14, 21 days for in vivo biodegradation study. SEM, histological and immunohistochemical analysis revealed that the typical LFPm fibrin structure was maintained until day 7, with a contemporary loss of cellular elements. From day 14, the morphology and texture of samples became less and less recognizable, confirming that a progressive biodegradation occurred. Overall, collected evidences could support the rationale for the clinical use of LFPms, shading some light on the regenerative effect they may exert after the autologous implant on a defect site

Italian Guidelines in diagnosis and treatment of alopecia areata

Alopecia areata (AA) is an organ-specific autoimmune disorder that targets anagen phase hair follicles. The course is unpredictable and current available treatments have variable efficacy. Nowadays, there is relatively little evidence on treatment of AA from well-designed clinical trials. Moreover, none of the treatments or devices commonly used to treat AA are specifically approved by the Food and Drug Administration. The Italian Study Group for Cutaneous Annexial Disease of the Italian Society of dermatology proposes these Italian guidelines for diagnosis and treatment of Alopecia Areata deeming useful for the daily management of the disease. This article summarizes evidence-based treatment associated with expert-based recommendations