Potential methodological influences on the determination of particle retention efficiency by suspension feeders: Mytilus edulis and Ciona intestinalis

The retention efficiency (RE) of suspension-feeding bivalve molluscs depends on particle size and is generally assumed to decline below a maximum retention of particles larger than 3 to 7 µm. Previous suggestions that the RE spectrum of mussels Mytilus edulis can exhibit variability, possibly as a result of physiological regulation, have been attributed to artifacts associated with the indirect method. The possibility that variable physical properties of seston particles and/or miscalculations can result in inaccurate RE measurements was examined using 3 methodologies (static, flow-through and a new approach based on the static method) and 3 particle sources (natural seston, algal cell monocultures and clay). Measurements obtained with the static method varied depending on the selected sampling interval. However, this artifact can be removed using frequent sampling and a regression analysis approach. Accurate RE measurements can be obtained with the flow-through method when feeding behaviour is flow independent. For all particle suspensions and methods, mussels from the study site in Lysefjord, Norway, had a maximum RE for particles >8–11 µm (1 to 5 September 2015). The RE for smaller particles declined gradually, with 50–60% retention of 4 µm particles and 30–40% retention of 2 µm particles. Differences in the RE size spectra of mussels and tunicates Ciona intestinalis, collected and measured at the same site, further indicated that RE was not influenced by potentially confounding methodological factors. Assumptions regarding the RE spectrum of bivalves have contributed to many conclusions on their ecosystem interactions. The reliability of clearance rate measurements obtained using the indirect method can only be assured if the effective retention of tracer particles is confirmed and not assumed.publishedVersio

Influence of the organic matter on the specific surface of a Typic argiudoll

El contenido de materia orgánica (MO) del suelo se relaciona positivamente, en algunos casos, con la superficie específica (SE) del mismo, pero grandes cantidades de MO pueden resultar en una SE menor, cuando se la determina a través de la adsorción de nitrógeno a bajas temperaturas. Tradicionalmente se asocia a la MO una elevada SE, del orden de los 500 a 800 m2 g-1. Estos valores, obtenidos mediante técnicas que emplean solventes polares, por ejemplo, etilenglicol, hicieron suponer que la misma contribuye en gran medida a la SE del suelo. No obstante, hay referencias que señalan una sobrestimación de los resultados obtenidos, atribuida a la utilización de estos solventes. Mediciones que emplean el método con adsorción de N2 a 77 K, cuya interpretación se basa en el modelo de Brunauer, Emmett y Teller (BET), considerado internacionalmente como método patrón, arrojan valores de SE para la MO que son menores que los primeros, en dos órdenes de magnitud. Con el objetivo de aportar conocimiento que contribuyera a una mejor comprensión del papel de la MO en procesos edáficos, se realizaron determinaciones de SE en muestras de un Argiudol típico, con diferentes contenidos de MO y contenido de arcilla constante (20%). Las medidas se llevaron a cabo interpretando las isotermas de adsorción de N2 a 77 K, mediante el modelo BET. Los resultados obtenidos mostraron una relación no lineal negativa entre la SE y el contenido de MO. La eliminación de la MO mediante H2O2 incrementó la SE de las muestras en todos los casos. La variación de SE por unidad de MO eliminada sugiere que la misma no se adsorbe de manera uniforme y continua sobre la superficie de la fase mineral.The organic matter (OM) of soil is positively related to the specific surface area (SSA), but large amounts of OM result in reduced SSA when determined by the Brunauer-Emmett- Teller (BET) method with N2 adsorption at low temperature. It is common to assign a large SSA to OM, ranging from 500 to 800 m2 g-1. These values, obtained with methods using polar adsorbates, e.g. ethylene glycol, imply a high contribution of OM to soil SSA. However, some works claimed an overestimation of the effect of OM on SSA when polar solvents are used. Measurements with the BET method (using N2 at 77 K), considered internationally as a standard method, resulted in values of SSA for OM two order of magnitude smaller than the former ones. With the objective to contribute to a better knowledge about the OM role in edaphological processes, determinations of SSA in samples from a Typic argiudoll with different OM contents were made. Measurements of SSA were carried out with N2 at 77 K, and the isotherms were interpreted with the BET model. Results showed a negative non linear relationship between SSA and the OM content of the samples. Destruction of OM with H2O2 increased SSA in all cases. The increments in SSA, normalized by the content of removed OM, suggested that the adsorption of OM on the mineral surface is not uniform.Fil: Gelati, Pablo R..Fil: Sarli, Guillermo O..Fil: Soracco, Carlos Germán.Fil: Lozano, Luis A..Fil: Filgueira, Roberto R.

Evaluating events data for cultural analytics : a case study on the economic and social effects of Covid-19 on the Edinburgh Festivals

Funding: This work was supported by the Arts and Humanities Research Council under Grant AH/W007533/1.The effects of the Covid-19 pandemic on the Creative and Cultural Industries can be difficult to quantify. Metadata about events (theatre productions, music and comedy gigs, sporting fixtures, days out, and more) are an untapped resource for cultural analytics that can be used as a proxy metric for financial and social impact. This article uses a sample of large-scale cultural events data from UK industry providers Data Thistle to ask: how can events data at scale be used to quantify the financial and social effects of the Covid-19 pandemic on the cultural events sector in a particular region? We analysed the changes in event provision in Edinburgh in August 2018, 2019, 2020 and 2021, revealing an estimated 97.3% fall in ticketing revenue between 2019 and 2020. Additionally, the effects that pandemic restrictions had on different categories of event reveal a disparity in how different audience sectors were affected, with ‘Visual Art’ and ‘Days Out’ showing most resilience and ‘Theatre’, ‘Comedy’ and ‘LGBT’ events being most reduced. Our findings indicate that events data are a rich but heterogenous source of information regarding the cultural and creative economy, which is not yet routinely used by researchers.Peer reviewe

Common challenges and requirements

Research infrastructures available for researchers in environmental and Earth science are diverse and highly distributed; dedicated research infrastructures exist for atmospheric science, marine science, solid Earth science, biodiversity research, and more. These infrastructures aggregate and curate key research datasets and provide consolidated data services for a target research community, but they also often overlap in scope and ambition, sharing data sources, sometimes even sites, using similar standards, and ultimately all contributing data that will be essential to addressing the societal challenges that face environmental research today. Thus, while their diversity poses a problem for open science and multidisciplinary research, their commonalities mean that they often face similar technical problems and consequently have common requirements when addressing the implementation of best practices in curation, cataloguing, identification and citation, and other related core topics for data science. In this chapter, we review the requirements gathering performed in the context of the cluster of European environmental and Earth science research infrastructures participating in the ENVRI community, and survey the common challenges identified from that requirements gathering process

EXISTE UMA SOCIOLOGIA DO CORPO NO BRASIL?

This paper aims to identify the possible institution of a Sociology of the Body in Brazil. The body is understood as a social construct, as a phenomenon that exists within, and through, the social sphere, producing sense and meaning through socially located and manifest forms of embodiment. From a survey of Brazilian Social Science (specifically Sociology and Anthropology) and Physical Education papers, we identified sufficient research output to suggest the incipient nature of the Sociology of the Body in Brazil.El objetivo de este artículo es identificar la posible existencía de una sociología del cuerpo en Brasil. El cuerpo es entendido como una construcción social – como fenómeno que existe dentro y a través del social – produciendo sentidos y significados ubicados socialmente y que se manifestan en y a través de la corporeidad. A partir de uma revisión de la literatura en periódicos brasileños de los campos de conocimiento de las ciências sociales (específicamente sociología y antropología) y de la educación física, fueron identificados resultados que presentan el caracter incipiente de la sociologia del cuerpo en Brasil.O objetivo deste artigo é identificar a possível constituição de uma sociologia do corpo no Brasil. O corpo é entendido como uma construção social – como um fenômeno que existe dentro e através da esfera social – produzindo sentidos e significados localizados socialmente e manifestados na e pela corporeidade. A partir de uma pesquisa bibliográfica nos campos de conhecimento brasileiros das ciências sociais (especificamente sociologia e antropologia) e educação física, identificou-se resultados da investigação suficientes para sugerir o caráter incipiente da sociologia do corpo no Brasil

Three-dimensional printed polymeric system to encapsulate human mesenchymal stem cells differentiated into islet-like insulin-producing aggregates for diabetes treatment

Diabetes is one of the most prevalent, costly, and debilitating diseases in the world. Pancreas and islet transplants have shown success in re-establishing glucose control and reversing diabetic complications. However, both are limited by donor availability, need for continuous immunosuppression, loss of transplanted tissue due to dispersion, and lack of vascularization. To overcome the limitations of poor islet availability, here, we investigate the potential of bone marrow–derived mesenchymal stem cells differentiated into islet-like insulin-producing aggregates. Islet-like insulin-producing aggregates, characterized by gene expression, are shown to be similar to pancreatic islets and display positive immunostaining for insulin and glucagon. To address the limits of current encapsulation systems, we developed a novel three-dimensional printed, scalable, and potentially refillable polymeric construct (nanogland) to support islet-like insulin-producing aggregates’ survival and function in the host body. In vitro studies showed that encapsulated islet-like insulin-producing aggregates maintained viability and function, producing steady levels of insulin for at least 4 weeks. Nanogland—islet-like insulin-producing aggregate technology here investigated as a proof of concept holds potential as an effective and innovative approach for diabetes cell therapy