The emissivity of conductor Gaussian random rough surfaces: the surface impedance boundary condition method

AbstractWe are interested in studying the contributions of the physical parameters of materials to the emissivity of random rough surfaces for both transverse electric and transverse magnetic waves. Comparisons between the surface impedance boundary condition (SIBC) and the exact results are presented. The effects of the incident angle, the material surfaces and random roughness on the directional emissivity are quantified. The contributions of the effects to the emissivity are used to investigate the domains of validity of the approximate model

Dynamic images to address conceptual nodes about mechanical waves: Example materials and preliminary results of the experimentation of the teacher training module IMAGONDE

In the framework of the 2002-03 project “Fisica per la Formazione Culturale - FORMazione Insegnanti” funded by Italy ministry of Education, a set of training materials, focused on mechanical waves, has been developed. The core of the materials is represented by animated images purposely designed in order to: 1) address intrinsically dynamic aspects of one-dimensional impulses/waves propagation on a string; 2) have the trainees reflect upon students’ difficulties in reading/interpreting static images (as the ones which are featured in common textbooks) and animations. In this paper we discuss example materials concerning transversal impulses on strings to address conceptual nodes such as: 1) configuration of the string at a given time and its abstract representation; 2) displacement vs. time graph of a string element and its abstract representation; 3) relationships between the two abstract representations; 4) modelization of mechanical wave propagation in one dimension. Moreover the results of the experimentation of the training materials in the framework of the Post Graduate School to Became Physics Teacher in Secondary Schools are presented and commented

Musculoskeletal Diseases Role in the Frailty Syndrome: A Case-Control Study.

Frailty syndrome severely burdens older age, and musculoskeletal diseases are of paramount importance in its development. The aim of this study is to unravel the contribution of musculoskeletal diseases to frailty syndrome. This is a case-control study, and we enrolled 55 robust community-dwelling age- and gender-matched patients, with 58 frail and pre-frail subjects. Frailty was diagnosed according to the Fried criteria (FP), and the Fragility Index (FI) was calculated. In all the subjects, a comprehensive geriatric assessment was carried out. Their nutritional status was evaluated by the Mini Nutritional Assessment and Bioelectrical Impedance Analyses. Their bone density (BMD), bone turnover, muscle mass, strength and performance were evaluated. Here, we show that the prevalence of frailty varies according to the diagnostic criteria used and that FP and FI showed a moderate to good agreement. Despite age and gender matching, frail subjects had lower muscle strength, performance and BMD. Their quality of life and cognitive performance were reduced in the frail subjects compared to the robust ones. Muscular strength and performance, together with mood, significantly predicted the diagnosis of frailty, whereas BMD and bone turnover did not. In conclusion, we show that sarcopenia plays a pivotal role in predicting the diagnosis of frailty, whereas osteoporosis does not

Establishment of a patient-derived intrahepatic cholangiocarcinoma xenograft model with KRAS mutation.

BACKGROUND: Intrahepatic cholangiocarcinoma (ICC) is an aggressive, highly lethal tumors and lacks of effective chemo and targeted therapies. Cell lines and animal models, even partially reflecting tumor characteristics, have limits to study ICC biology and drug response. In this work, we created and characterized a novel ICC patient-derived xenograft (PDX) model of Italian origin. METHODS: Seventeen primary ICC tumors derived from Italian patients were implanted into NOD (Non-Obese Diabetic)/Shi-SCID (severe combined immunodeficient) mice. To verify if the original tumor characteristics were maintained in PDX, immunohistochemical (cytokeratin 7, 17, 19, and epithelial membrane antigen) molecular (gene and microRNA expression profiling) and genetic analyses (comparative genomic hybridization array, and mutational analysis of the kinase domain of EGFR coding sequence, from exons 18 to 21, exons 2 to 4 of K-RAS, exons 2 to 4 of N-RAS, exons 9 and 20 of PI3KCA, and exon 15 of B-RAF) were performed after tumor stabilization. RESULTS: One out of 17 (5.8 %) tumors successfully engrafted in mice. A high molecular and genetic concordance between primary tumor (PR) and PDX was confirmed by the evaluation of biliary epithelial markers, tissue architecture, genetic aberrations (including K-RAS G12D mutation), and transcriptomic and microRNA profiles. CONCLUSIONS: For the first time, we established a new ICC PDX model which reflects the histology and genetic characteristics of the primary tumor; this model could represent a valuable tool to understand the tumor biology and the progression of ICC as well as to develop novel therapies for ICC patients. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12885-016-2136-1) contains supplementary material, which is available to authorized users

Normative values of resting heart rate variability in young male contact sport athletes: Reference values for the assessment and treatment of concussion

Objective: The objective of this study was to identify the main determinants of heart rate variability (HRV) in male athletes aged 14 to 21 years who practice competitive contact sports and to integrate these determinants with the aim of defining normative values of short-term HRV in the time and frequency domains. Methods: Participants (n = 369) were aged 14 to 21 years and included 221 football players and 148 ice hockey players. HRV was measured for 5 min at rest, and standard HRV parameters in the time and frequency domains were calculated. Heart rate (HR), age, body mass index (BMI), number of sports weekly practices (WSP) and concussion history (mTBI) were considered determinants potentially able to influence HRV. Results: Multiple regression analysis revealed that HR was the primary determinant of standard HRV parameters. The models accounted for 13% to 55% of the total variance of HRV and the contribution of HR to this model was the strongest (β ranged from −0.34 to −0.75). HR was the only determinant that significantly contributes to all HRV parameters. To counteract this dependence, we calculated HRV corrected by the mean RR interval (RRm). Such corrections do not remove any physiological differences in HRV; they simply remove the mathematical bias. HRV parameters were therefore normalized, and their normative limits were developed relative to the mean heart rate. After correction, the correlation coefficients between HR and all corrected HRV parameters were not statistically significant and ranged from −0.001 to 0.045 (p > 0.40 for all). The automatically corrected HRV calculator, which recalculates standard HRV parameters and converts them into corrected parameters in addition to determining whether a given value is within normal limits, facilitates clinical interpretation. Conclusion: This study provides for the first time corrected normative values of short-term and resting state HRV parameters in competitive contact sport athletes aged 14 to 21 years. These values were developed independently of the major determinants of HRV. The baseline values for HRV parameters given here could be used in clinical practice when assessing and monitoring cerebral concussions. They may assist in decision making for a safe return to play. 2023 Ziadia, Sassi, Trudeau and Fait

Broiler on-farm welfare assessment: Insights on the applicability of the transect method

Los pollos de engorde se crían en grupos de miles de aves, bajo condiciones ambientales y de manejo controladas. Sin embargo, el entorno puede deteriorarse rápidamente, especialmente hacia el final del periodo de cría, ocasionando problemas de bienestar. La posibilidad de realizar una evaluación efectiva del bienestar del pollo de engorde en condiciones de cría comercial presenta desafíos importantes debido al gran número de animales por lote. El método de los transectos ha sido sugerido como una herramienta práctica para la detección de los principales problemas de bienestar, incluyendo problemas de patas (inmóviles y cojos), enfermedades (enfermos y terminales), heridas (en cabeza, espalda y/o cola), aves pequeñas, sucias desplumadas y muertas. Las evaluaciones se realizan desplazándose a lo largo de los denominados transectos que se definen como el área delimitada entre líneas de comederos y bebederos o por la pared. Las evaluaciones se realizan utilizando la pantalla de evaluación de la aplicación móvil i-WatchBroiler a medida que el observador detecta problemas de bienestar a lo largo del recorrido del transecto. Resultados de estudios anteriores han demostrado la fiabilidad del método de transectos en lotes de pavos comerciales. Aunque este método de evaluación parece ser efectivo, es necesario realizar trabajos adicionales para probar el método de los transecto en diferentes condiciones experimentales. Por lo tanto, el objetivo de la presente Tesis Doctoral es investigar la aplicabilidad práctica y la solidez del método de los transectos para la evaluación del bienestar de pollos de engorde en granjas comerciales.El primer Capítulo de esta Tesis consiste en una revisión bibliográfica de las herramientas de ganadería de precisión utilizadas para controlar aspectos que afectan directamente al bienestar de las aves de producción, y del pollo de carne en particular. Las herramientas tecnológicas presentadas pueden indicar problemas de bienestar, salud y gestión. Estos incluyen sensores para monitoreo ambiental de la granja, movimiento de aves o parámetros fisiológicos; tecnologías de imágenes para detectar problemas de la marcha y picoteo de las plumas y tecnologías de infrarrojos para evaluar los cambios en la termorregulación y el metabolismo de las aves. Las oportunidades para una fácil recopilación y análisis de datos que ofrece el uso de las aplicaciones también abren nuevas oportunidades para un monitoreo fiable y eficiente del bienestar animal.En el segundo Capítulo, se presentan los resultados sobre la capacidad del método de los transectos para detectar los efectos de las distintas líneas genéticas del pollo de engorde, la calidad de cama y la posición de los transecto (pared vs centro), y de cómo estos efectos cambian con la edad. Se detectó un claro deterioro de la mayoría de los indicadores de bienestar con la edad de las aves. Una peor calidad de cama resultó en una mayor frecuencia de aves sucias, mientras que en los transectos de pared se observaron frecuencias más elevadas de pollos inmóviles, pequeños, enfermos, sucios y muertos. También se detectó una asociación entre el deterioro de los indicadores de bienestar y los resultados de producción recogidos en matadero. El aumento en la incidencia de enfermos y de la mortalidad en granja se asoció con un aumento de muertos a la llegada al matadero.El tercer Capítulo se centra en los efectos de incrementar la complejidad ambiental mediante la aplicación de estrategias de enriquecimiento ambiental sobre la incidencia de los indicadores de bienestar recopilados utilizando el método de los transectos y en los resultados de producción. La complejidad ambiental se refiere al número de tipos de enriquecimiento ambiental proporcionados (turba, balas de viruta de madera y cajas). Los resultados mostraron una incidencia decreciente de heridas, índice de problemas de bienestar (suma de todos los indicadores de bienestar), tasa de mortalidad, rechazos por heridas y aves pequeñas con mayor complejidad ambiental. En el mismo estudio, también se detectó una menor incidencia de problemas de patas, un menor índice de problemas de bienestar, menos rechazos debido a heridas, y una mayor tasa de crecimiento con el incremento del espacio disponible. La iluminación intermitente de 16h se relacionó con una menor incidencia de aves enfermas, heridas, y mortalidad. De manera similar a los resultados del Capítulo 2, se encontraron claras asociaciones entre los indicadores de bienestar obtenidos en granja y los resultados productivos. El aumento en la incidencia de problemas de patas, enfermedades, aves pequeñas y el índice de problemas de bienestar se asoció a un aumento en los rechazos por enfermedades, peso bajo y de rechazos totales.El cuarto Capítulo tuvo como objetivo evaluar la solidez del método de los transectos mediante la técnica de captura-recaptura de una subpoblación (80 individuos marcados individualmente) conocida de pollos de carne en condiciones comerciales. Dos observadores realizaron 4 muestreos/nave/día, recogiendo la posición de las aves detectadas. Se estimaron las tasas de detección y repetición de individuos por nave y transecto, y se determinó el efecto de la densidad, del número de transecto /nave (6 vs 8) y del momento de muestreo (mañana vs tarde). En promedio, se detectaron dos tercios de la subpoblación marcada con un 23.85% de tasa de repetición al evaluar toda la nave y 1.66% de repetición por transecto. Además se ha demostrado que se obtiene una tasa de repetición mínima si los dos transectos evaluados están separados por tres transectos. Las diferencias en el índice de distribución indican que las aves no distribuyen al azar, y por lo tanto, se deben evaluar tanto los transectos centrales como los de pared. Una evaluación representativa se puede obtener muestreando solo dos transectos de la nave de acuerdo con los resultados de bootstrapping de los datos de transectos.Por tanto se puede concluir que los resultados obtenidos mediante la aplicación del método de los transectos en la evaluación del pollo de engorde serían los esperables al probar la asociación entre la incidencia de los indicadores de bienestar y las condiciones ambientales y de manejo de la granja. Los resultados sugieren que se pueden realizar evaluaciones sólidas de bienestar mediante el muestreo de dos transectos, siendo estos uno central y otro de pared, separados por tres transectos intermedios. Los resultados obtenidos en los diferentes estudios de esta Tesis Doctoral respaldan la validez del método de los transectos que se puede utilizar como un método práctico y sólido de evaluación del bienestar en las granjas comerciales del pollo de engorde.<br /

Biological and technical variables affecting immunoassay recovery of cytokines from human serum and simulated vaginal fluid: A multicenter study

The increase of proinflammatory cytokines in vaginal secretions may serve as a surrogate marker of unwanted inflammatory reaction to microbicide products topically applied for the prevention of sexually transmitted diseases, including HIV-1. Interleukin (IL)-1β and IL-6 have been proposed as indicators of inflammation and increased risk of HIV-1 transmission; however, the lack of information regarding detection platforms optimal for vaginal fluids and interlaboratory variation limit their use for microbicide evaluation and other clinical applications. This study examines fluid matrix variants relevant to vaginal sampling techniques and proposes a model for interlaboratory comparisons across current cytokine detection technologies. IL-1β and IL-6 standards were measured by 12 laboratories in four countries, using 14 immunoassays and four detection platforms based on absorbance, chemiluminescence, electrochemiluminescence, and fluorescence. International reference preparations of cytokines with defined biological activity were spiked into (1) a defined medium simulating the composition of human vaginal fluid at pH 4.5 and 7.2, (2) physiologic salt solutions (phosphate-buffered saline and saline) commonly used for vaginal lavage sampling in clinical studies of cytokines, and (3) human blood serum. Assays were assessed for reproducibility, linearity, accuracy, and significantly detectable fold difference in cytokine level. Factors with significant impact on cytokine recovery were determined by Kruskal−Wallis analysis of variance with Dunn’s multiple comparison test and multiple regression models. All assays showed acceptable intra-assay reproducibility; however, most were associated with significant interlaboratory variation. The smallest reliably detectable cytokine differences (P < 0.05) derived from pooled interlaboratory data varied from 1.5- to 26-fold depending on assay, cytokine, and matrix type. IL-6 but not IL-1β determinations were lower in both saline and phosphate-buffered saline as compared to vaginal fluid matrix, with no significant effect of pH. The (electro)chemiluminescence-based assays were most discriminative and consistently detected <2-fold differences within each matrix type. The Luminex-based assays were less discriminative with lower reproducibility between laboratories. These results suggest the need for uniform vaginal sampling techniques and a better understanding of immunoassay platform differences and cross-validation before the biological significance of cytokine variations can be validated in clinical trials. This investigation provides the first standardized analytic approach for assessing differences in mucosal cytokine levels and may improve strategies for monitoring immune responses at the vaginal mucosal interface

Severe peripheral joint laxity is a distinctive clinical feature of spondylodysplastic-ehlers-danlos syndrome (Eds)-b4galt7 and spondylodysplastic-eds-b3galt6

Variations in genes encoding for the enzymes responsible for synthesizing the linker region of proteoglycans may result in recessive conditions known as “linkeropathies”. The two phenotypes related to mutations in genes B4GALT7 and B3GALT6 (encoding for galactosyltransferase I and II respectively) are similar, characterized by short stature, hypotonia, joint hypermobility, skeletal features and a suggestive face with prominent forehead, thin soft tissue and prominent eyes. The most outstanding feature of these disorders is the combination of severe connective tissue involvement, often manifesting in newborns and infants, and skeletal dysplasia that becomes apparent during childhood. Here, we intend to more accurately define some of the clinical features of B4GALT7 and B3GALT6-related conditions and underline the extreme hypermobility of distal joints and the soft, doughy skin on the hands and feet as features that may be useful as the first clues for a correct diagnosis