Influence of Matrix Polarity on the Properties of Ethylene Vinyl Acetate–Carbon Nanofiller Nanocomposites

A series of ethylene vinyl acetate (EVA) nanocomposites using four kinds of EVA with 40, 50, 60, and 70 wt% vinyl acetate (VA) contents and three different carbon-based nanofillers—expanded graphite (EG), multi-walled carbon nanotube (MWCNT), and carbon nanofiber (CNF) have been prepared via solution blending. The influence of the matrix polarity and the nature of nanofillers on the morphology and properties of EVA nanocomposites have been investigated. It is observed that the sample with lowest vinyl acetate content exhibits highest mechanical properties. However, the enhancement in mechanical properties with the incorporation of various nanofillers is the highest for EVA with high VA content. This trend has been followed in both dynamic mechanical properties and thermal conductivity of the nanocomposites. EVA copolymer undergoes a transition from partial to complete amorphousness between 40 and 50 wt% VA content, and this changes the dispersion of the nanofillers. The high VA-containing polymers show more affinity toward fillers due to the large free volume available and allow easy dispersion of nanofillers in the amorphous rubbery phase, as confirmed from the morphological studies. The thermal stability of the nanocomposites is also influenced by the type of nanofiller

La “donación patriótica” de Manuel Ancízar a la Biblioteca Nacional (1849-1853)

Objective: This article focuses on Manuel Ancízar Basterra’s donation (1811-1882) to the National Library of New Granada in 1849. The aim is to identify the conditions that made this transaction possible and what it reveals about the relationship between the donator and the institution. Methodology: First, it characterizes the donation based on a quantitative and qualitative analysis of its content. Second, it introduces some elements related to its formation: a previous inventory, as well as some marks on the books, are evidence of the origins of some of the volumes —linked in several cases to the intellectual networks where Ancízar was immersed—, and of the selection processes that shaped the collection delivered to the Library. Third, it makes explicit the symbolic characteristics of the donation in a context of political and educational changes promoted by the liberal governments of the time. Originality: This investigation invites to question the construction of narratives about the bibliographic heritage and proposes new elements to analyze the scholars and its legacy. Conclusions: The collection went through a selection process before turning from the private to the public domain, which was not about the cession of Ancízar’s personal library and the transaction was one among several strategies of the agent to position itself in the New Granada scholar field. Finally, the analysis of inventories, both historical and contemporary, reveals that Ancízar’s books were dispersed among the Library’s assets, and the current Fund has few similarities with the original donation.Objetivo: este artigo se concentra na doação de Manuel Ancízar Basterra (1811-1882) para a Biblioteca Nacional da Colômbia em 1849. Trata-se de uma pesquisa para identifica quais foram as condições que tornaram possível a transação e o que revela esta do vínculo entre o doador e a instituição. Metodologia: primeiro, a doação é caracterizada com base na análise —quantitativa e qualitativa— de seu conteúdo. Em segundo lugar, alguns elementos referentes à construtividade da coleção são apresentados: a existência de um inventário prévio, assim como algumas marcas nos livros, comprovam a procedência de uma parte dos títulos, —ligados em vários casos às redes intelectuais nas quais Ancízar estava imerso—, e os processos de seleção que moldaram o conjunto de livros efetivamente entregues à Biblioteca. Em terceiro lugar, as características simbólicas da doação são explicitadas em um contexto de mudanças políticas e educacionais promovidas pelos governos liberais da época. Originalidade: esta pesquisa convida a questionar a construção de narrativas sobre o patrimônio bibliográfico e propõe novos elementos para interpretar o intelectual e seu legado. Conclusões: conclui-se que a coleção foi depurada antes de passar do domínio privado para o público, que não se tratou da entrega da biblioteca pessoal de Ancízar e que a transação foi uma entre várias estratégias do agente para se posicionar no campo intelectual da Nova Granada. Da mesma forma, a análise dos inventários, tanto históricos como contemporâneos, revela que a coleção de livros de Ancízar estava dispersa entre os itens do acervo da Biblioteca, e que a coleção que atualmente se encontra na instituição tem poucas semelhanças com a doação original.Objetivo: este artículo se centra en la donación de Manuel Ancízar Basterra (1811-1882) a la Biblioteca Nacional de la Nueva Granada en 1849. Se busca identificar cuáles fueron las condiciones que hicieron posible la transacción y lo que esta revela sobre el vínculo entre el donante y la institución. Metodología: primero, se caracteriza la donación a partir del análisis —cuantitativo y cualitativo— de su contenido. En segundo lugar, se presentan algunos elementos referentes a la formación de la colección: tanto la existencia de un inventario previo, como algunas marcas en los libros, evidencian la procedencia de una parte de los títulos —ligados en varios casos a las redes intelectuales en las que Ancízar se vio inmerso—, y los procesos de selección que dieron forma al conjunto de libros efectivamente entregado a la Biblioteca. En tercer lugar, se hacen explícitas las características simbólicas de la donación en un contexto de cambios políticos y educativos impulsados por los gobiernos liberales del momento. Originalidad: esta investigación invita a cuestionar la construcción de narrativas sobre el patrimonio bibliográfico y propone nuevos elementos para interpretar al intelectual y su legado. Conclusiones: se concluye que la colección fue depurada antes de pasar del dominio privado al dominio público, que no se trató de la entrega de la biblioteca personal de Ancízar y que la transacción fue una entre varias estrategias del agente para posicionarse en el campo intelectual neogranadino. Asimismo, el análisis de inventarios, tanto históricos como contemporáneos, revela que el conjunto de libros de Ancízar se disgregó entre los haberes de la Biblioteca y que el fondo que hoy se encuentra en la institución tiene pocas similitudes con la donación original

Anaesthesia praCtice for Caesarean dElivery Snapshot Study (ACCESS): Protocol and baseline characteristics of registered centres

Background: Specific guidelines to manage caesarean delivery anaesthesia are lacking. A European multicentre study, ACCESS investigates caesarean delivery anaesthesia management in European centres. In order to identify ACCESS participating centres, a registration survey was created. Objective: The aim of the current report is to describe the characteristics of ACCESS study participating centres, the rationale for the ACCESS study and the study methodology. Design and setting: The ACCESS study is a European multicentre cross-sectional study to describe anaesthesia management for caesarean delivery (CD) using a snapshot (2-week) design. The ACCESS registration survey gathered: contact details for National Coordinators (NC); Lead Investigators (LI) per centre; centre annual CD volume; expected no. of CD during 2-week snapshot window; centre practice information; data collection language. The ACCESS registration survey was launched July 2022 (Google Forms, Google Inc., Mountain View, CA, USA) and distributed through personal connections, national and international societies, social media networks, during Euroanaesthesia 2023, through the European Society of Anaesthesiology and Intensive Care newsletter. Results: The ACCESS registration survey identified Lead Investigators for 418 centres, in 32 countries, representing an anticipated number of 15,073 CD cases over the planned 12-month study period. A median (range) of 20 (2 to 400) CD cases are anticipated per centre during the 2-week snapshot window. Most 366/418 (87.6%) centres are small, ≤2000 annual CD cases, 42 are medium 2000-5000 cases and 10 are large, ≥5000 annual CD cases. Registered centres reported in 134 (32.0%) centres that anaesthesia for caesarean delivery is performed mostly by a specialist obstetric anaesthesiologist. Conclusion: The ACCESS registration survey revealed variability in volume and CD practice as well as training-levels and staffing among European countries. The ACCESS study (https://www.access-study.org/) aims to generate practice data to guide CD anaesthetic management strategies.Sin financiación1.9 Q2 JCR 20230.743 Q2 SJR 2023No data IDR 2022UE