Localizing the cross-links distribution in elastomeric composites by tailoring the morphology of the curing activator

The localization of the rubber vulcanization reaction close to the silica filler surface was investigated in isoprene rubber composites (IR NCs): the main goal was to highlight the role of curing agents’ dispersion and filler surface features on the spatial propagation of the rubber cross-links and the resulting mechanical behavior of the material. The study was realized by tailoring the morphology of the curing activator, i.e. by vulcanizing IR NCs with Zn@SiO2 double function filler, composed of Zn(II) single sites anchored on SiO2 filler, in comparison to silica filled IR NCs vulcanized with microcrystalline ZnO (m-ZnO). The microscopic cross-links distribution was measured by Transmission Electron Microscopy for network visualization (NVTEM) and Time Domain Nuclear Magnetic Resonance (TD-NMR). Besides the NCs mechanical behavior was characterized both at small strain and at fracture. In the presence of Zn@SiO2, higher cross-link density in proximity to SiO2 particles was evidenced, which gradually spreads from the filler surface to the bulk, induced by localization of the Zn(II) centers. IR NCs with Zn@SiO2 resulted stiffer (+45%) and with a lower fracture toughness (less than one third), compared to m-ZnO based NCs, which shows a quite homogeneous structure of the rubber cross-links network. The results highlighted the correlation between the composites structural features and their macroscopic behavior, paving the way to modulating the mechanical properties of elastomeric materials by tuning the nature of the curing agents

Quantifying and Mitigating Wind‐Induced Undercatch in Rainfall Measurements

Despite the apparent simplicity, it is notoriously difficult to measure rainfall accurately because of the challenging environment within which it is measured. Systematic bias caused by wind is inherent in rainfall measurement and introduces an inconvenient unknown into hydrological science that is generally ignored. This paper examines the role of rain gauge shape and mounting height on catch efficiency (CE), where CE is defined as the ratio between nonreference and reference rainfall measurements. Using a pit gauge as a reference, we have demonstrated that rainfall measurements from an exposed upland site, recorded by an adjacent conventional cylinder rain gauge mounted at 0.5 m, were underestimated by more than 23% on average. At an exposed lowland site, with lower wind speeds on average, the equivalent mean undercatch was 9.4% for an equivalent gauge pairing. An improved-aerodynamic gauge shape enhanced CE when compared to a conventional cylinder gauge shape. For an improved-aerodynamic gauge mounted at 0.5 m above the ground, the mean undercatch was 11.2% at the upland site and 3.4% at the lowland site. The mounting height of a rain gauge above the ground also affected CE due to the vertical wind gradient near to the ground. Identical rain gauges mounted at 0.5 and 1.5 m were compared at an upland site, resulting in a mean undercatch of 11.2% and 17.5%, respectively. By selecting three large rainfall events and splitting them into shorter-duration intervals, a relationship explaining 81% of the variance was established between CE and wind speed

LDPE-based blends and films stabilized with nonreleasing polymeric antioxidants for safer food packaging

Several novel random copolymers of ethylene and 1-olefin counits bearing a highly efficient phenolic antioxidant moiety placed at different distances from the polymerizable double bond were prepared in the presence of a metallocene catalyst. These copolymers were melt-blended with an antioxidant-free LDPE in an internal batch mixer to obtain innovative materials containing nonreleasing polymeric antioxidants suitable for safer food packaging applications. Blends and films, obtained by compression molding, were tested for their thermal and thermo-oxidative stability by thermogravimetric analysis both in dynamic and isothermal conditions. Films containing the macromolecular antioxidants showed a longer induction time before O2 uptake starts and, consequently, a higher degradation temperature than neat LDPE or LDPE containing a low molecular weight commercial additive. Aging tests demonstrated that the new polymeric antioxidants also exert a valid protection against photo-oxidation. Eventually, migration tests demonstrated the absence of any trace of products containing the antioxidant moiety when the films were kept in contact with a food simulant

Modulation of Barrier Properties of Monolayer Films from Blends of Polyethylene with Ethylene-co-Norbornene

Flexible monolayer films with modulated diffusional and optical properties were achieved from blends of a LDPE/LLDPE matrix and an ethylene/norbornene copolymer (COC). A significant decrease of O2 and CO2 permeability was observed for cast films with COC content from 5 to 20 wt %. SEM analysis showed that, despite the incompatibility of the blend components, good dispersion and distribution of the COC domains in the PE matrix were achieved; as a consequence, for COC content ranging from 5 to 10 wt % the film transparency results practically unchanged. The UV light transmission decreased on increasing the percentage of COC, which constitutes also a protection against UV radiations. A noticeable improvement was observed in the mechanical properties: adding only 5 wt % of COC, the elastic modulus becomes five times higher than that of the PE matrix. The rheological behaviour of the blends keeps practically unchanged with respect to the matrix, allowing to use the typical LDPE processing conditions. Sustainable inexpensive flexible films answering the packaging requirements of specific categories of food were achieved

Removal allura red dye by bentonite and organobentonite

El método de adsorción de diversos contaminantes, empleando minerales arcillosos, es una de las técnicas más factibles de utilizar a la hora de la remediación de efluentes contaminados. La factibilidad del proceso radica principalmente en el bajo costo de los materiales adsorbentes, por ser abundantes en la naturaleza, y sus características naturales: reducido tamaño de partícula, capacidad de intercambio catiónico y elevada superficie específica. Sin embargo, aquellos efluentes contaminados con tintes coloreados orgánicos provenientes de diversas industrias (textil, alimenticia, plásticos, papel, entre otras) suelen no ser retenidos por las arcillas naturales debido a su naturaleza hidrofílica. Ésta problemática podría solucionarse si se realiza un tratamiento de intercambio de iones inorgánicos por orgánicos, que modifiquen las propiedades superficiales naturales de la arcilla, dando origen a lo que se conoce como organoarcilla. La remoción de tintes de naturaleza orgánica es una problemática que crece día a día debido a la falta de controles ambientales en las aguas de desechos, originadas por industrias cada vez más abundantes debido al creciente consumo de productos manufacturados (papel, plásticos, textiles, cueros, gomas, etc.). Los colorantes orgánicos usados para impartir color a los productos, tienen la particularidad de ser muy solubles en agua y, debido a que, generalmente, tienen estructuras aromáticas complejas, son biológicamente no degradables y presentan alta estabilidad y toxicidad, representando una inminente amenaza ambiental. Es por lo expuesto que el objetivo del presente trabajo es evaluar el empleo de una bentonita y una organobentonita, en la remoción del tinte orgánico Red Allura, por medio de ensayos de adsorción. Los sólidos adsorbentes y la solución coloreada a retener fueron estudiados empleando técnicas analíticas instrumentales de Difracción de Rayos X (DRX), Espectrometría Infrarroja (IR), Análisis Térmico Termogravimétrico (TG) y Espectrometría UV-visible. Se efectuaron experiencias de adsorción del colorante con una concentración inicial de 250mg.L-1, en sistema batch, a temperatura ambiente, durante 24 horas, variando las relaciones sólido/líquido; transcurrido éste tiempo se extrajeron alícuotas del sobrenadante para su cuantificación, recuperando los sólidos previa eliminación de la solución no retenida, mediante reiterados lavados con agua destilada. Los datos obtenidos indicarían una adsorción favorable del colorante en estudio por la organobentonita.Trabajo publicado en Maria dos Santos Alfonso y Rosa María Torres Sánchez (eds.). Enfoques Interdisciplinarios para la Sustentabilidad del Ambiente. Buenos Aires: Editorial Sociedad Argentina de Ciencia y Tecnología Ambiental, 2015.Centro de Investigación y Desarrollo en Ciencias AplicadasComisión de Investigaciones Científicas de la provincia de Buenos Aire

ps8 161 the disease burden in patients with longstanding systemic lupus erythematosus focus on health resource use and costs

Introduction As a consequence of increased SLE patients survival, patients with long disease duration represent a significant proportion of our cohorts. This study aims to evaluate health resource use and the 6 months costs in patients with SLE with long disease duration. Methods The economic evaluation was performed in terms of cost-of-illness analysis as part of a larger study enrolling SLE patients with at least 15 years of disease duration regularly followed at our unit. At enrollment, the following information were collected: disease activity (SLEDAI), organ damage (SLICC-DI score), comorbidities, treatment patterns; in addition to clinical data, patients were required to complete an ad-hoc questionnaire for the collection of facts relevant for the estimation of the economic dimension and covering the previous six-months. Such a time frame was considered to be appropriate as recall period. Direct health (drugs, hospitalizations, emergency visits, specialists visits, laboratory tests and instrumental examination) and non-health costs (transportation and accommodation) as well as indirect costs because of productivity loss were estimated. Results 51 adult patients with long disease duration were recruited (98% female, mean age 49±11 years, median disease duration 17 years, IQR 15–23). Median (IQR) SLEDAI score was 2 (0–4), median SLICC-DI was 1 (0–2). The median (IQR) direct health costs per patients over the previous 6 months resulted 410€ (201–1687); indirect costs because of productivity lost were 130€ (0–356). The median overall cost to the Society was 473€ (327–2148); the presence of comorbid conditions resulted associated with higher overall cost for the Society (552€ [327–1807] vs 264€ [94–1164] p=0.046); disease activity and damage at enrollment were not associated with costs increase in this cohort. Conclusions This cohort of patients with long lasting disease is characterised by low disease activity and mild organ damage; in this setting, the disease burden on the single patient and family is significant and the costs to the Society are influenced by the presence of comorbidities

Removal allura red dye by bentonite and organobentonite

El método de adsorción de diversos contaminantes, empleando minerales arcillosos, es una de las técnicas más factibles de utilizar a la hora de la remediación de efluentes contaminados. La factibilidad del proceso radica principalmente en el bajo costo de los materiales adsorbentes, por ser abundantes en la naturaleza, y sus características naturales: reducido tamaño de partícula, capacidad de intercambio catiónico y elevada superficie específica. Sin embargo, aquellos efluentes contaminados con tintes coloreados orgánicos provenientes de diversas industrias (textil, alimenticia, plásticos, papel, entre otras) suelen no ser retenidos por las arcillas naturales debido a su naturaleza hidrofílica. Ésta problemática podría solucionarse si se realiza un tratamiento de intercambio de iones inorgánicos por orgánicos, que modifiquen las propiedades superficiales naturales de la arcilla, dando origen a lo que se conoce como organoarcilla. La remoción de tintes de naturaleza orgánica es una problemática que crece día a día debido a la falta de controles ambientales en las aguas de desechos, originadas por industrias cada vez más abundantes debido al creciente consumo de productos manufacturados (papel, plásticos, textiles, cueros, gomas, etc.). Los colorantes orgánicos usados para impartir color a los productos, tienen la particularidad de ser muy solubles en agua y, debido a que, generalmente, tienen estructuras aromáticas complejas, son biológicamente no degradables y presentan alta estabilidad y toxicidad, representando una inminente amenaza ambiental. Es por lo expuesto que el objetivo del presente trabajo es evaluar el empleo de una bentonita y una organobentonita, en la remoción del tinte orgánico Red Allura, por medio de ensayos de adsorción. Los sólidos adsorbentes y la solución coloreada a retener fueron estudiados empleando técnicas analíticas instrumentales de Difracción de Rayos X (DRX), Espectrometría Infrarroja (IR), Análisis Térmico Termogravimétrico (TG) y Espectrometría UV-visible. Se efectuaron experiencias de adsorción del colorante con una concentración inicial de 250mg.L-1, en sistema batch, a temperatura ambiente, durante 24 horas, variando las relaciones sólido/líquido; transcurrido éste tiempo se extrajeron alícuotas del sobrenadante para su cuantificación, recuperando los sólidos previa eliminación de la solución no retenida, mediante reiterados lavados con agua destilada. Los datos obtenidos indicarían una adsorción favorable del colorante en estudio por la organobentonita.Trabajo publicado en Maria dos Santos Alfonso y Rosa María Torres Sánchez (eds.). Enfoques Interdisciplinarios para la Sustentabilidad del Ambiente. Buenos Aires: Editorial Sociedad Argentina de Ciencia y Tecnología Ambiental, 2015.Centro de Investigación y Desarrollo en Ciencias AplicadasComisión de Investigaciones Científicas de la provincia de Buenos Aire

Potential Risks of Excess Iodine Ingestion and Exposure: Statement by the American Thyroid Association Public Health Committee

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140261/1/thy.2014.0331.pd

Hypoglycemia and Clinical Outcomes in Patients With Diabetes Hospitalized in the General Ward

OBJECTIVE: Hypoglycemia is associated with adverse outcomes in mixed populations of patients in intensive care units. It is not known whether the same risks exist for diabetic patients who are less severely ill. In this study, we aimed to determine whether hypoglycemic episodes are associated with higher mortality in diabetic patients hospitalized in the general ward. RESEARCH DESIGN AND METHODS: This retrospective cohort study analyzed 4,368 admissions of 2,582 patients with diabetes hospitalized in the general ward of a teaching hospital between January 2003 and August 2004. The associations between the number and severity of hypoglycemic (≤50 mg/dl) episodes and inpatient mortality, length of stay (LOS), and mortality within 1 year after discharge were evaluated. RESULTS: Hypoglycemia was observed in 7.7% of admissions. In multivariable analysis, each additional day with hypoglycemia was associated with an increase of 85.3% in the odds of inpatient death (P = 0.009) and 65.8% (P = 0.0003) in the odds of death within 1 year from discharge. The odds of inpatient death also rose threefold for every 10 mg/dl decrease in the lowest blood glucose during hospitalization (P = 0.0058). LOS increased by 2.5 days for each day with hypoglycemia (P < 0.0001). CONCLUSIONS: Hypoglycemia is common in diabetic patients hospitalized in the general ward. Patients with hypoglycemia have increased LOS and higher mortality both during and after admission. Measures should be undertaken to decrease the frequency of hypoglycemia in this high-risk patient population