Microstructure and high temperature mechanical properties of hard TaSiN coatings

Hard nitride coatings are widely used in the cutting tool industry, where coatings are commonly exposed to high temperature under service conditions. The addition of Si into nitride coatings, such as the TaSiN system, has been shown to enhance their oxidation resistance [1], which coupled with its high hardness, make this system of great interest for many engineering applications involving high temperatures. In this study, the room and high temperature mechanical properties of magnetron sputtered TaSiN coatings were measured using nanoindentation (between 25°C and 500°C). Fracture toughness was also evaluated at a similar temperature range using the micro-pillar splitting method (see Figure 1). The effects of N2 flow ratios on the composition, evolving phases and microstructure of the obtained nanocrystalline TaSiN coatings before and after the high temperature testing were examined by RBS, XRD and TEM analysis. Hardness was observed to increase with N content as we approach stoichiometries that allow higher degrees of crystallization of the TaN hard phases, which are embedded in an amorphous matrix. Coatings with an optimal composition of Ta55Si10N35 retain a hardness value of up to 30 GPa at 500°C, being also the toughest. Please click Additional Files below to see the full abstract

Management of wet age-related macular degeneration in Spain: Challenges for treat and extend implementation in routine clinical practice

Purpose. To ascertain wet AMD (wAMD) management patterns in Spain. Methods. A two-round Delphi study conducted through a questionnaire-based survey designed from literature review and validated by an independent Steering Committee. Results. Forty-nine retina specialists experienced in wAMD participated by answering the two-round study questionnaire. Retina specialists are the main responsible for wAMD diagnosis and monitoring, including visits and associated procedures, with a median time per visit of 15 minutes. Standard treatment strategies are based on anti-VEGF administration, including standard loading dose administration followed by maintenance with aflibercept or ranibizumab (81% of patients). Although treat and extend (T&E) dosing strategy is considered as optimal for wAMD management (78% of the panelists), the main routine healthcare limitations (i.e., visits overload, reduced staff, short visit time, coordination issues, lack of facilities) conduct to self-defined “flexible” strategies, based on T&E and pro-re-nata (PRN) protocols. Conclusion. Proactive treatment patterns (T&E) are the preferred ones by the retina specialists in Spain. However, their proper implementation is difficult due to healthcare resource limitations, as well as organisation and logistic issues. .e use of anti-VEGF agents with longer duration of action could facilitate the use of strict T&E approaches according to routine clinical practicesThe study has been sponsored by Bayer Hispania S.L. Logistic

Riereta.net. : Apuntes epistemo-políticos desde una etnografía tecnoactivista

En este artículo exponemos una experiencia de investigación etnográfica en Riereta, taller tecnoactivista de Barcelona dedicado al desarrollo e implementación de software libre y tecnologías de la información (TICs) al servicio de proyectos y colectivos activistas de la ciudad. A través de nuestra experiencia responderemos a una serie de cuestiones metodológicas pero también epistemo-políticas: ¿qué herramientas metodológicas implementar que permitan experienciar la dimensión semiótico-material del fenómeno?, ¿cómo introducir la tecnología en nuestra acción investigativa?, ¿qué metodología desarrollar que sea coherente con los deseos y "modos de vida" de las participantes? o ¿cómo dar cuenta de las múltiples voces disonantes que componen toda comprensión etnográfica y práctica creativa?. Interrogantes que se podrían resumir en cómo hacer de la investigación social y esta práctica etnográfica una forma de acción tecnopolítica. Para ello organizamos el artículo en torno a tres ejes: 1) cuál fue la relación entre sujetos y objetos de investigación, y que transitó desde una aproximación a la co-investigación hasta una perspectiva epistémica articulatoria; 2) la metodología empleada, próxima a una perspectiva etnográfica performativa y virtual que se apoya en herramientas tecnológicas como el Tiki-Wiki; y 3) los productos del proceso de investigación: comprensiones colectivas y situadas acerca del tecnoactivismoIn this article we report on an ethnographic research experience on Riereta, a techno-activist workshop located in Barcelona, where free software and other technologies are developed and put at the disposal of other political projects and activist collectives. Through our research experience, we answer some methodological issues but also raise related epistemic and political questions: What kind of methodical tools must we implement in order to experience the semiotic and material dimension of the subject? How to introduce the technology in our research activity? What kind of methodology can we develop if we want to be consistent with participants' wishes and ways of life? or How to take account of multiple and different voices that compose every ethnographic comprehension and creative practice? All of these questions could be summarized as an quest for turning social research and ethnographic practice into techno-political action. The article is organized in three parts: 1) the relationship between research subjects and objects variously constituted, shifting from a co-research perspective to an epistemologically articulated one; 2) the methodology applied, close to a performative and virtual ethnographic perspective where some technological tools, such as Tiki-Wiki (http://en.wikipedia.org/wiki/TikiWiki), are used; and 3) the products of the research process: collective and situated understandings of technoactivis

Microarchitected Compliant Scaffolds of Pyrolytic Carbon for 3D Muscle Cell Growth

The integration of additive manufacturing technologies with the pyrolysis of polymeric precursors enables the design-controlled fabrication of architected 3D pyrolytic carbon (PyC) structures with complex architectural details. Despite great promise, their use in cellular interaction remains unexplored. This study pioneers the utilization of microarchitected 3D PyC structures as biocompatible scaffolds for the colonization of muscle cells in a 3D environment. PyC scaffolds are fabricated using micro-stereolithography, followed by pyrolysis. Furthermore, an innovative design strategy using revolute joints is employed to obtain novel, compliant structures of architected PyC. The pyrolysis process results in a pyrolysis temperature- and design-geometry-dependent shrinkage of up to 73%, enabling the geometrical features of microarchitected compatible with skeletal muscle cells. The stiffness of architected PyC varies with the pyrolysis temperature, with the highest value of 29.57 ± 0.78 GPa for 900 °C. The PyC scaffolds exhibit excellent biocompatibility and yield 3D cell colonization while culturing skeletal muscle C2C12 cells. They further induce good actin fiber alignment along the compliant PyC construction. However, no conclusive myogenic differentiation is observed here. Nevertheless, these results are highly promising for architected PyC scaffolds as multifunctional tissue implants and encourage more investigations in employing compliant architected PyC structures for high-performance tissue engineering applications

Asociación de espermatozoides en el epidídimo de rata. Expresión de Serpina 1F, una proteína involucrada en este proceso madurativo.

La asociación epididimaria de espermatozoides es un fenómenoobservado en numerosas especies de mamíferos. Cuando los espermatozoides madurosalcanzan la cola del epidídimo pueden asociarse entre sí mediante sus cabezasformando estructuras características, cuya morfología depende de cada especie. Entrelas cabezas asociadas se describió la presencia de un material electron denso denaturaleza proteica. En la rata estas asociaciones se denominan ”rosetas“. De estemodo, los espermatozoides permanecen almacenados hasta la eyaculación. Una vezdepositados en el tracto reproductor femenino o bien liberados a un medio de cultivo seactiva la movilidad espermática. Esto produce que uno a uno los espermatozoides sedesprendan originando una suspensión de células móviles y aisladas. En las especiesde mamíferos estudiadas, este proceso de asociación reversible se relaciona con elgrado de maduración alcanzado por los espermatozoides. En cuanto a la funciónbiológica se ha propuesto tanto la protección de las gametas frente a una reacciónacrosomal anticipada como la adquisición de una una mayor velocidad dedesplazamiento de las asociaciones lo que supondría ventaja en caso de competenciaespermática. En trabajos previos nuestro grupo aisló e identifico en el fluido epididimariode la región caudal de rata la proteína Serpina 1 F que pertenece a la familia de lasSerpinas (inhibidores de serin proteasas). Luego demostramos que Serpina 1Fparticipaba en la asociación epididimaria de espermatozoides en esta especie medianteensayos de re asociación in vitro

Improving the detection of infectious diseases in at-risk migrants with an innovative integrated multi-infection screening digital decision support tool (IS-MiHealth) in primary care : a pilot cluster-randomized-controlled trial

There are major shortfalls in the identification and screening of at-risk migrant groups. This study aims to evaluate the effectiveness of a new digital tool (IS-MiHealth) integrated into the electronic patient record system of primary care centres in detecting prevalent migrant infections. IS-MiHealth provides targeted recommendations to health professionals for screening multiple infections, including human immunodeficiency virus (HIV), hepatitis B and C, active tuberculosis (TB), Chagas disease, strongyloidiasis and schistosomiasis, based on patient characteristics (including variables of country of origin, age and sex). A pragmatic pilot cluster-randomized-controlled trial was deployed from March to December 2018. Eight primary care centres in Catalonia, Spain, were randomly allocated 1:1 to use of the digital tool for screening, or to routine care. The primary outcome was the monthly diagnostic yield of all aggregated infections. Intervention and control sites were compared before and after implementation with respect to their monthly diagnostic yield using regression models. This study is registered on international standard randomised controlled trial number (ISRCTN) (ISRCTN14795012). A total of 15 780 migrants registered across the eight centres had at least one visit during the intervention period (March-December 2018), of which 14 598 (92.51%) fulfilled the criteria to be screened for at least one infection. There were 210 (2.57%) individuals from the intervention group with new diagnoses compared with 113 (1.49%) from the control group [odds ratio: 2.08, 95% confidence interval (CI) 1.63-2.64, P < 0.001]. The intervention centres raised their overall monthly diagnosis rate to 5.80 (95% CI 1.23-10.38, P = 0.013) extra diagnoses compared with the control centres. This monthly increase in diagnosis in intervention centres was also observed if we consider all cases together of HIV, hepatitis B and C, and active TB cases [2.72 (95% CI 0.43-5.00); P = 0.02] and was observed as well for the parasitic infections' group (Chagas disease, strongyloidiasis and schistosomiasis) 2.58 (95% CI 1.60-3.57; P < 0.001). The IS-MiHealth increased screening rate and diagnostic yield for key infections in migrants in a population-based primary care setting. Further testing and development of this new tool is warranted in larger trials and in other countries

Efecto del aceite de oliva sobre el metabolismo del colesterol en conejos hipercolesterolémicos.

El aceite de oliva, componente esencial de la Dieta Mediterránea, posee efectosbeneficiosos sobre la hipercolesterolemia, principal factor de riesgo de enfermedadescardiovasculares. La administración de una dieta grasa en conejos provoca laacumulación de colesterol en la membrana celular del espermatozoide y se correlacionacon defectos en la biogénesis del acrosoma y de la cabeza en general. Este incrementode colesterol interfiere con el normal funcionamiento de la gameta masculina y podría sercausa de infertilidad masculina. Interesantemente, la administración de aceite de oliva aestos animales mejoró los parámetros alterados por la ingesta grasa.Nuestro interés reside en estudiar la vía intracelular de colesterol en testículo deconejos bajo diferentes dietas experimentales. El efecto beneficioso del aceite de oliva anivel celular no ha sido estudiado a nivel celular/molecular

Sperm parameters and epididymis function in transgenic rats overexpressing the Ca-2-binding protein regucalcin: a hidden role for Ca-2 in sperm maturation?

Sperm undergo maturation acquiring progressive motility and the ability to fertilize oocytes through exposure to the components of the epididymal fluid (EF). Although the establishment of a calcium (Ca-2) gradient along the epididymis has been described, its direct effects on epididymal function remain poorly explored. Regucalcin (RGN) is a Ca-2-binding protein, regulating the activity of Ca-2-channels and Ca-2-ATPase, for which a role in male reproductive function has been suggested. This study aimed at comparing the morphology, assessed by histological analysis, and function of epididymis, by analysis of sperm parameters, antioxidant potential and Ca-2 fluxes, between transgenic rats overexpressing RGN (Tg-RGN) and their wild-type littermates. Tg-RGN animals displayed an altered morphology of epididymis and lower sperm counts and motility. Tissue incubation with Ca-45(2) showed also that epididymis of Tg-RGN displayed a diminished rate of Ca-2-influx, indicating unbalanced Ca-2 concentrations in the epididymal lumen. Sperm viability and the frequency of normal sperm, determined by the one-step eosin-nigrosin staining technique and the Diff-Quik staining method, respectively, were higher in Tg-RGN. Moreover, sperm of Tg-RGN rats showed a diminished incidence of tail defects. Western blot analysis demonstrated the presence of RGN in EF as well as its higher expression in the corpus region. The results presented herein demonstrated the importance of maintaining Ca-2-levels in the epididymal lumen and suggest a role for RGN in sperm maturation. Overall, a new insight into the molecular mechanisms driving epididymal sperm maturation was obtained, which could be relevant to development of better approaches in male infertility treatment and contraception.Portuguese Foundation for Science and Technology (FCT) under Program COMPETE [PEst-C/SAU/UI0709/2011]; FCT; FCT fellowships [SFRH/BD/60945/2009, SRFH/BPD/80451/2011]info:eu-repo/semantics/publishedVersio

Vector capabilities in GRASS GIS

Vector capabilities in GRASS GIS: an overview of vector topology and its application in network analysi