Evolution of aerial spider webs coincided with repeated structural optimization of silk anchorages

Physical structures built by animals challenge our understanding of biological processes and inspire the development of smart materials and green architecture. It is thus indispensable to understand the drivers, constraints, and dynamics that lead to the emergence and modification of building behavior. Here, we demonstrate that spider web diversification repeatedly followed strikingly similar evolutionary trajectories, guided by physical constraints. We found that the evolution of suspended webs that intercept flying prey coincided with small changes in silk anchoring behavior with considerable effects on the robustness of web attachment. The use of nanofiber based capture threads (cribellate silk) conflicts with the behavioral enhancement of web attachment, and the repeated loss of this trait was frequently followed by physical improvements of web anchor structure. These findings suggest that the evolution of building behavior may be constrained by major physical traits limiting its role in rapid adaptation to a changing environment

Management of Dyslipidaemia in Real-world Clinical Practice: Rationale and Design of the VIPFARMA ISCP Project.

Dyslipidaemia plays a major role in the pathogenesis of atherosclerosis. Every year, scientific institutions publish cardiovascular prevention guidelines with updated goals and recommendations based on new evidence. However, medical barriers exist that make achieving these goals difficult and gaps between guidelines and best daily clinical practice still persist. The International Society of Cardiovascular Pharmacotherapy designed the Surveillance of Prescription Drugs in the Real World Project (VIPFARMA ISCP), a survey for physicians who manage lipid disorders in high-risk patients. Seven clusters of questions will be analysed comprising demographics, institution profile, access to continuing medical education, clinical practice profile, attitude regarding use of statins, knowledge regarding proprotein convertase subtilisin/kexin type 9 inhibitors and attitudes regarding medical decisions about triglycerides. The present study will be the first part of a larger programme and aims to shed light on barriers between lipid-lowering drug therapy recommendations in the 2019 European Society of Cardiology guidelines and clinical practice in different countries

A theoretical-numerical model for the peeling of elastic membranes

The adhesive behaviour of biological attachment structures such as spider web anchorages is usually studied using single or multiple peeling models involving "tapes", i.e. one-dimensional contacts elements. This is an oversimplification for many practical problems, since the actual delamination process requires the modelling of complex two-dimensional adhesive elements. To achieve this, we develop a numerical approach to simulate the detachment of an elastic membrane of finite size from a substrate, using a 3D cohesive law. The model is validated using existing analytical results for simple geometries, and then applied in a series of parametric studies. Results show how the pull-off force can be tuned or optimized by varying different geometrical or mechanical parameters in various loading scenarios, and the length of the detachment boundary, known as the peeling line, emerges as the key factor to maximize adhesion. The approach presented here can allow a better understanding of the mechanical behaviour of biological adhesives with complex geometries or with material anisotropies, highlighting the interaction between the stress distributions at the interface and in the membrane itself.Comment: 48 pages, 12 figure

Influenza and Pneumococcal Vaccination in Patients with Cardiovascular Disease: Pilot Project

Introducción Se recomienda la vacunación antiinfluenza y antineumocóccica en adultos con trastornos cardiovasculares, pero existe una subutilización de las mismas.   Objetivo Describir la tasa de inmunización de los pacientes luego de la indicación sistemática de las vacunas antigripal y antineumocóccica, y las barreras en su implementación. Evaluar si la indicación desde la unidad coronaria se asocia con mayor adherencia.   Métodos Estudio unicéntrico prospectivo. Durante un mes en época epidémica, se prescribió sistemáticamente vacunación antigripal y antineumocóccica al egreso de unidad coronaria ó en consultorios externos a pacientes con indicación para las mismas. Seguimiento a 30 días con contacto telefónico.   Resultados Se reclutaron 80 pacientes, mediana 65 años, 67% masculinos, 8% cobertura de salud prepaga y el resto obras sociales. 31% indicación de inmunización al egreso de unidad coronaria.  Durante el seguimiento sólo 72% se habían inmunizado con la vacuna antigripal y 45% con la antineumocóccica. Los principales motivos descriptos para no inmunización fueron decisión personal del paciente, problemas de obra social y costos de las vacunas. Se observó tendencia a mayor inmunización antineumocóccica si la indicación se realizaba desde la unidad coronaria en comparación con los consultorios (OR 1,47[0,5-4] p=0,2).   Conclusiones Un gran porcentaje de los pacientes a los que se les indican las vacunas no se inmunizan efectivamente, siendo la principal barrera la decisión personal. La tendencia a mayor tasa de inmunización al egreso de unidad coronaria en comparación con el consultorio es una potencial oportunidad para mejorar la adherencia, que debería ser demostrada en estudios de mayor escala

Crisis económico-financieras en la Argentina: ¿un nuevo factor de riesgo de mortalidad cardiovascular?

Introduccion En estudios clinicos y experimentales se ha documentado la relacion entre el impacto generado por diversas situaciones traumaticas, como guerras, ataques terroristas y desastres naturales, y la mortalidad en diferentes regiones del mundo y los resultados de un estudio reciente muestran que las crisis financieras, en ausencia de desastres naturales o guerras, podrian tener un impacto negativo sobre la mortalidad cardiovascular. La experiencia actual sugiere que las crisis del sistema financiero podrian tener una influencia importante sobre la salud. Objetivos Describir las tendencias de las tasas de mortalidad cardiovascular (TMCV) en la Argentina entre los anos 1995 y 2005 y explorar si los cambios en ellas coinciden temporalmente con cambios en las tendencias del Producto Interno Bruto (PIB) como indicador de crisis economico-financieras. Material y metodos Se calculo la TMCV anual por 100.000 utilizando la base de datos del Ministerio de Salud de la Nacion (Clasificacion Internacional de Enfermedades 9.o y 10.o). Se consideraron las siguientes causas de defuncion: insuficiencia cardiaca (IC), infarto agudo de miocardio (IAM), enfermedad coronaria (EC) cronica y accidente cerebrovascular (ACV). Para los denominadores se utilizaron las proyecciones de poblacion del Instituto Nacional de Estadistica y Censos. Se identificaron dos crisis economicas: la del sudeste asiatico (1998-1999) y la caida de la convertibilidad (2001- 2002). Se aplicaron modelos de joinpoint para evaluar los cambios en las tendencias. Resultados El PIB presento una tendencia ascendente (pendiente = 17,18) desde 1995 hasta 1998, luego una tendencia descendente (pendiente = .12,90) hasta 2002 y una tendencia ascendente (pendiente = 19,88) hasta 2005 y la TMCV descendio un 24,72% (de 474,9 a 357,5 por 100.000). El modelo de joinpoint identifico tres pendientes en la TMCV: la primera desde 1995 hasta 1997 de .17,94, la segunda hasta 2002 con una tendencia al descenso (pendiente = .6,8) y la tercera hasta 2005 con pendiente de .16,73. Las tasas de mortalidad por IC, IAM y ACV siguieron un comportamiento similar con un descenso del 22,95%, 16,89% y 38,06%, respectivamente. Conclusiones La estrecha relacion temporal entre el aumento relativo de la mortalidad cardiovascular y el descenso del PIB permitiria considerar a las crisis economico-financieras como un nuevo factor de riesgo psicosocial.Background The relationship between the impact generated by diverse traumatic situations as wars, terrorist attacks and natural disasters with mortality in different regions of the world has been documented in clinical and experimental studies. A recent study showed that, in the absence of natural disasters or wars, financial crises might have a negative impact on cardiovascular mortality. The current experience suggests that financial crises could have a significant influence on health. Objective To describe the trends in cardiovascular mortality rates (CVMR) in Argentina between 1995 and 2005, and to explore if there is a close temporal relationship with the changes in trends of the Gross Domestic Product (GDP) as indicator of economic and financial crisis. Material and Methods The annual CVMR per 100,000 persons was calculated using the information obtained from the database of the Ministry of Health (9th and 10th International Classification of Diseases). The following causes of death were considered: heart failure (HF), acute myocardial infarction (AMI), chronic ischemic heart disease (IHD) and stroke (CVA). The population estimates used as the denominator were obtained from the National Institute of Statistics and Censuses. Two economic crises were identified: the Southeast Asia crisis (1998-1999) and the end of the convertibility system (2001-2002). Joinpoint models were used to evaluate changes in trends. Results GDP showed an increasing trend (slope = 17.18) from 1995 to 1998, which decreased in the period 1998-2002 (slope = 12.90) and increased from 2002 to 2005 (slope = 19.88); CVMR decreased by 24.72% (from 474.9 to 357.5 per 100,000). The joinpoint model identified three slopes in CVMR: from 1995 to 1997 ( 17.94), a descending slope until 2002 ( 6.8) and an increasing slope until 2005 (slope 16.73). Mortality rates due to HF, MI and CVA had a similar trend, decreasing by 22.95%, 16.89% and 38.06%, respectively. Conclusions The close temporal relationship between the relative increase in cardiovascular mortality and the reduction of GDP might consider economic and financial crises as a novel psychosocial risk factor