Remote activation by green-light irradiation of shape memory epoxies containing gold nanoparticles

Shape memory epoxies (SMEs) that can be remotely activated by the use of green light, are described. An epoxy matrix based on on diglycidylether of bisphenol A (DGEBA cured with a mixture of n-dodecylamine (DA) and m-xylylenediamine (MXDA), exhibits excellent shape memory properties as described in a previous paper (Leonardi et al., 2011). Au NPs with an average diameter close to 5 nm could be uniformly dispersed in this matrix using poly(ethylene oxide) (PEO) chains as stabilizer. These NPs showed a significant photothermal effect even at very low concentrations (0.01 wt% as metallic gold), when irradiated with a 532 nm laser at a power close to 2 W/cm2. Under these conditions, a bended bar (1.4-mm thickness) recovered its initial shape in a few seconds. This formulation may be used to build up devices with the necessary mechanical strength and with the possibility to produce shape recovery by remote activation using green light. A second example was analyzed employing an amphiphilic epoxy matrix to produce a uniform dispersion of Au NPs stabilized with dodecyl chains (average diameter close to 3 nm). A bar (1.4-mm thickness) of the SME with 0.04 wt% Au NPs (as metallic gold) showed a fast recovery of its initial shape by irradiation with a 532 nm laser at a power close to 2 W/cm2. This example shows the feasibility of adapting the epoxy chemistry to disperse Au NPs stabilized with different ligands and obtained through robust synthetic methods.Fil: Leonardi, Agustina Belen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Puig, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Antonacci, Julian. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Departamento de Física; ArgentinaFil: Arenas, Gustavo Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Departamento de Física; ArgentinaFil: Zucchi, Ileana Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Hoppe, Cristina Elena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Reven, Linda. McGill University; CanadáFil: Zhu, Liu. Peking University Shenzhen Graduate School; ChinaFil: Toader, Violeta. McGill University; CanadáFil: Williams, Roberto Juan Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentin

Changing times: resilience

info:eu-repo/semantics/publishedVersio

Prospective Risk Assessment of Medicine Shortages in Europe and Israel: Findings and Implications

Introduction: While medicine shortages are complex, their mitigation is more of a challenge. Prospective risk assessment as a means to mitigate possible shortages, has yet to be applied equally across healthcare settings. The aims of this study have been to: 1) gain insight into risk-prevention against possible medicine shortages among healthcare experts; 2) review existing strategies for minimizing patient-health risks through applied risk assessment; and 3) learn from experiences related to application in practice. Methodology: A semi-structured questionnaire focusing on medicine shortages was distributed electronically to members of the European Cooperation in Science and Technology (COST) Action 15105 (28 member countries) and to hospital pharmacists of the European Association of Hospital Pharmacists (EAHP) (including associated healthcare professionals). Their answers were subjected to both qualitative and quantitative analysis (Microsoft Office Excel 2010 and IBM SPSS Statistics®) with descriptive statistics based on the distribution of responses. Their proportional difference was tested by the chi-square test and Fisher's exact test for independence. Differences in the observed ordinal variables were tested by the Mann-Whitney or Kruskal-Wallis test. The qualitative data were tabulated and recombined with the quantitative data to observe, uncover and interpret meanings and patterns. Results: The participants (61.7%) are aware of the use of risk assessment procedures as a coping strategy for medicine shortages, and named the particular risk assessment procedure they are familiar with failure mode and effect analysis (FMEA) (26.4%), root cause analysis (RCA) (23.5%), the healthcare FMEA (HFMEA) (14.7%), and the hazard analysis and critical control point (HACCP) (14.7%). Only 29.4% report risk assessment as integrated into mitigation strategy protocols. Risk assessment is typically conducted within multidisciplinary teams (35.3%). Whereas 14.7% participants were aware of legislation stipulating risk assessment implementation in shortages, 88.2% claimed not to have reported their findings to their respective official institutions. 85.3% consider risk assessment a useful mitigation strategy. Conclusion: The study indicates a lack of systematically organized tools used to prospectively analyze clinical as well as operationalized risk stemming from medicine shortages in healthcare. There is also a lack of legal instruments and sufficient data confirming the necessity and usefulness of risk assessment in mitigating medicine shortages in Europe. © Copyright © 2020 Miljković, Godman, Kovačević, Polidori, Tzimis, Hoppe-Tichy, Saar, Antofie, Horvath, De Rijdt, Vida, Kkolou, Preece, Tubić, Peppard, Martinez, Yubero, Haddad, Rajinac, Zelić, Jenzer, Tartar, Gitler, Jeske, Davidescu, Beraud, Kuruc-Poje, Haag, Fischer, Sviestina, Ljubojević, Markestad, Vujić-Aleksić, Nežić, Crkvenčić, Linnolahti, Ašanin, Duborija-Kovačević, Bochenek, Huys and Miljković

Multiomics in the central Arctic Ocean for benchmarking biodiversity change

Multiomics approaches need to be applied in the central Arctic Ocean to benchmark biodiversity change and to identify novel species and their genes. As part of MOSAiC, EcoOmics will therefore be essential for conservation and sustainable bioprospecting in one of the least explored ecosystems on Earth

OptiCor (Optimising the treatment of chronic ischemic heart disease by training general practitioners to deliver very brief advice on physical activity)

Development and evaluation of a complex intervention (training for GPs in giving advice on physical activity) to improve primary care of patients with chronic ischemic heart disease. Funded in the context of a junior research group in health services research by the Federal Ministry of Education and Research (BMBF) German

Neurolisteriosis en adultos: a propósito de seis casos clínicos Neurolisteriosis in adults: report of six clinical cases

INTRODUCCION: Listeria monocytogenes tiene una especial predilección por infectar el sistema nervioso central y sus cubiertas meningeas. Afecta a pacientes que se encuentran en edades extremas de la vida, pacientes con deficiencia en su inmunidad celular y adultos sanos. La forma mas común de manifestarse es la meningitis aguda, aunque puede expresarse como cerebritis, encefalitis de tronco (romboencefalitis), y excepcionalmente mielitis. CASUISTICA: Se presentan y comentan seis casos clinicos de neurolisteriosis, cinco en adultos sanos, con sus hallazgos imagenológicos y licuorales. RESULTADOS: Tres de los pacientes se presentaron como meningitis aguda, uno como meningoencefalitis, otro como cerebritis y el restante como romboencefalitis. Se destaca el carácter turbio o ligeramente turbio del líquido cefalo-raquideo (LCR), la glucorraquia normal detectada en tres de los casos y el diagnostico realizado en cinco de los casos por cultivo del LCR. Se comenta la resonancia magnética singular del caso de la romboencefalitis con microabscesos en tronco. Todos los pacientes tuvieron evolución satisfactoria con tratamiento antibiotico. CONCLUSIÓN: La neurolisteriosis debe ser un diagnostico a tener en cuenta no solo en pacientes inmunocomprometidos o en edades extremas de la vida. Debe también tenerse en cuenta en pacientes adultos jóvenes sanos procedentes de regiones donde las condiciones sanitarias son precarias y no existe un adecuado control en la elaboración de alimentos.INTROCTION: Listeria monocytogenes shows a special attraction to infect the central nervous system and its meningeals coats. It affects newborn as well as elderly people, patients with deficiencies in their cellular inmune systems, and healthy adults. It presents most commonly as an acute meningitis, although it can present itself as cerebritis, brain stem encephalitis (rhomboencephalitis), and exceptionally as myelitis. PATIENTS: We describe six clinical cases of neurolisterioris, five of which in healthy adults; we also describe the images and cerebrospinal fluid (CSF) findings, RESULTS: Three patients contracted acute meningitis, one of them meningoencephalitis, one cerebritis and the last one rhomboencephalitis. The CSF was turbid or slightly turbid with normal glycorrachia in three patients. The diagnosis was made in five through culture of CSF. The patient with the rhomboencephalitis had brain stem microabscesses in the brain magnetic resonance. All the patients had a good outcome under antibiotics treatment. CONCLUSION: Neurolisteriosis has to be kept in mind as a feasible diagnosis not only in immunocompromised but also in newborn as well as elderly patients. It should also be taken into account in young healthy adults living in regions under poor sanitary conditions where there is no adequate control of food manufacturing

Thermal annealing as an easy tool for the controlled arrangement of gold nanoparticles in block-copolymer thin films

The results indicated that all three blends used as modifiers (PSn/PSnSH@Au) were successfully located in the PS phase during thermally induced BC self-assembly for a composition range from 5 to 43 wt% without macro-phase separation. The PSnSH@Au moiety experienced molecular desorption, nanocrystal core coalescence and partial molecular re-encapsulation processes during thermal annealing, leading to sphere-like gold NPs with a larger average size (without exceeding an interdomain distance). Ligand chain length regulated the degree of coalescence and re-encapsulation, defining ultimate core size. Furthermore, proper combination of chain length and composition enabled tuning of NP partitioning and arrangement on different length scales through thermally activated cooperative assembly processes. These results have not only significant impact for establishing thermal processing as a useful tool for the precise control of NP size and distribution, but also much broader implications for many nanoparticle-based technologies.Fil: Ledo Suárez, Ana. Universidad de Santiago de Compostela; España; Centre for Research in Biological Chemistry and Molecular Materials; España;Fil: Hoppe, Cristina Elena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación en Ciencia y Tecnología de Materiales (i); Argentina; Universidad Nacional de Mar del Plata. Facultad de Ingenieria; Argentina;Fil: Lazzari, Massimo. Universidad de Santiago de Compostela. Centre for Research in Biological Chemistry and Molecular Materials; España;Fil: Lopez-Quintela, Arturo M.. Universidad de Santiago de Compostela. Facultad de Química; España;Fil: Zucchi, Ileana Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación en Ciencia y Tecnología de Materiales (i); Argentina; Universidad Nacional de Mar del Plata. Facultad de Ingenieria; Argentina

From spherical micelles to hexagonally packed cylinders: the cure cycle determines nanostructures generated in block copolymer/ epoxy blends

Block copolymer (BCP)/epoxy blends have been intensively investigated during the past decade. Macrophase separation of the BCP in the cured thermoset is avoided by selecting one block that is initially immiscible or that phase separates early in the polymerization and another block that remains miscible up to high conversions. But the quality of the thermoset as a solvent of the miscible block varies along the cure cycle with both conversion and temperature. It shifts from a good solvent to a poor solvent, and eventually to a nonsolvent, by increasing conversion mainly due to the increase in the average molar mass before gelation and the cross-link density after gelation. It also changes with temperature due to the corresponding variation of the interaction parameter. Therefore, for a constant BCP concentration different nanostructures might be accessed and fixed by changing the cure cycle. This can be of interest to modulate final properties of the material (e.g., toughness, transparency, etc.). The selected system to prove this concept was a solution of 20 wt % PS-b-PMMA (Mn = 67 100, ΦPS = 0.69) in a stoichiometric mixture of diglycidyl ether of bisphenol A (DGEBA) and 4,4′- methylenebis(2,6-diethylaniline) (MDEA). Generated nanostructures varied with the selected cure cycle from a dispersion of spherical micelles to a dual morphology consisting of domains of hexagonally packed cylinders and regions with a dispersion of spherical micelles. This produced changes in transparency and in dynamic-mechanical properties of the resulting nanocomposites.Fil: Romeo, Hernan Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación en Ciencia y Tecnología de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingenieria; ArgentinaFil: Zucchi, Ileana Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación en Ciencia y Tecnología de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingenieria; ArgentinaFil: Rico, Maite. Universidad da Coruña; EspañaFil: Hoppe, Cristina Elena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación en Ciencia y Tecnología de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingenieria; ArgentinaFil: Williams, Roberto Juan Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación en Ciencia y Tecnología de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingenieria; Argentin

A modifier that enables the easy dispersion of alkyl-coated nanoparticles in an epoxy network

Nanoparticles (NPs) coated with alkyl chains cannot be dissolved in diglycidylether of bisphenol A (DGEBA), which is a typical monomer used in the synthesis of epoxy networks. We show that adding small amounts of the linear amphiphilic polymer obtained by reaction of DGEBA with dodecylamine, produced a stable dispersion of dodecanethiol-coated gold NPs in DGEBA. The anionic homopolymerization of this blend initiated by a tertiary amine led to a nanocomposite with a uniform dispersion of gold NPs. The selected crosslinking chemistry allowed covalent bonding of the modifier to the matrix, avoiding phase separation and enabling easy tuning of the thermal properties of the matrix.Fil: Puig, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación En Ciencia y Tecnología de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; ArgentinaFil: Zucchi, Ileana Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación En Ciencia y Tecnología de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; ArgentinaFil: Hoppe, Cristina Elena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación En Ciencia y Tecnología de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; ArgentinaFil: López Quintela, M. Arturo. Universidad de Santiago de Compostela; EspañaFil: Williams, Roberto Juan Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación En Ciencia y Tecnología de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; Argentin