Influence of Polyol/Crosslinker Blend Composition on Phase Separation and Thermo-Mechanical Properties of Polyurethane Thin Films

[EN] Polyurethanes (PUs) from Polyethylene glycol (PEG) and polycaprolactone diol (PCL) and a crosslinker, Pentaerythritol (PE), were synthetized with isophorone diisocyanate (IPDI). In this study, we investigated the effect of polyol and crosslinker composition on phase separation and thermo-mechanical properties. The properties were studied through dynamic mechanical analysis, X-ray scattering, atomic force microscopy (AFM), and thermogravimetric analysis (TGA). The results showed changes in PUs properties, microphase structure, and separation due to the composition of polyol/crosslinker blend. So, the largest concentration of PE produced multimodal loss factor patterns, indicating segment segregation while PUs with a PEG/PCL = 1 displayed a monomodal loss factor pattern, indicating a homogeneously distributed microphase separation. Additionally, the increase of the PEG concentration enhanced the damping capacity. On the other hand, agglomeration and thread-like structures of hard segments (HS) were observed through AFM. Finally, the thermal behavior of PUs was affected by chemical composition. Lower concentration of PE reduced the crosslinking; hence, the temperature with the maximum degradation rate.This work was supported by: Universidad de La Sabana (Grant number ING-176-2016); COLCIENCIAS, today Minister of Science, Technology and Innovation of the republic of Colombia, (Grant number 808-2018); Fondo Francisco Jose de Caldas (Contract number CT22-2017). CIBER-BBN is an initiative funded by the VI National R&D & I Plan 2008-2011, "IniciativaIngenio 2010", Consolider Program. CIBER actions are financed by the "Instituto de Salud Carlos III" with assistance from the European Regional Development Fund. DocumentArevalo-Alquichire, S.; Morales-Gonzalez, M.; Navas-Gomez, K.; Diaz, LE.; Gómez-Tejedor, J.; Serrano, M.; Valero, MF. (2020). Influence of Polyol/Crosslinker Blend Composition on Phase Separation and Thermo-Mechanical Properties of Polyurethane Thin Films. Polymers. 12(3):1-13. https://doi.org/10.3390/polym12030666S113123Kim, H.-N., Lee, D.-W., Ryu, H., Song, G.-S., & Lee, D.-S. (2019). Preparation and Characterization of Isosorbide-Based Self-Healable Polyurethane Elastomers with Thermally Reversible Bonds. Molecules, 24(6), 1061. doi:10.3390/molecules24061061Arévalo-Alquichire, S., Morales-Gonzalez, M., Diaz, L., & Valero, M. (2018). Surface Response Methodology-Based Mixture Design to Study the Influence of Polyol Blend Composition on Polyurethanes’ Properties. Molecules, 23(8), 1942. doi:10.3390/molecules23081942Brzeska, J., Elert, A., Morawska, M., Sikorska, W., Kowalczuk, M., & Rutkowska, M. (2018). Branched Polyurethanes Based on Synthetic Polyhydroxybutyrate with Tunable Structure and Properties. Polymers, 10(8), 826. doi:10.3390/polym10080826Klinedinst, D. 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New approach to recycle office waste paper: Reinforcement for polyurethane with nano cellulose crystals extracted from waste paper. Waste Management, 95, 59-69. doi:10.1016/j.wasman.2019.06.003Lei, W., Fang, C., Zhou, X., Li, Y., & Pu, M. (2018). Polyurethane elastomer composites reinforced with waste natural cellulosic fibers from office paper in thermal properties. Carbohydrate Polymers, 197, 385-394. doi:10.1016/j.carbpol.2018.06.036Ma, C., Chen, E., Sun, T., Shi, S., & Fang, Q. (2012). Preparation and characterization of tetrapod-shaped ZnO whisker filled polyurethane cross-linked epoxy/polyurethane damping composites. Journal of Reinforced Plastics and Composites, 31(22), 1564-1575. doi:10.1177/0731684412446856HUDA, M., DRZAL, L., MOHANTY, A., & MISRA, M. (2006). Chopped glass and recycled newspaper as reinforcement fibers in injection molded poly(lactic acid) (PLA) composites: A comparative study. 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Journal of Elastomers & Plastics, 52(5), 410-431. doi:10.1177/0095244319863153Schön, P., Bagdi, K., Molnár, K., Markus, P., Pukánszky, B., & Julius Vancso, G. (2011). Quantitative mapping of elastic moduli at the nanoscale in phase separated polyurethanes by AFM. European Polymer Journal, 47(4), 692-698. doi:10.1016/j.eurpolymj.2010.09.029Sui, H. L., Liu, X. Y., Zhong, F. C., Li, X. Y., & Ju, X. (2013). A study of radiation effects on polyester urethane using two-dimensional correlation analysis based on thermogravimetric data. Polymer Degradation and Stability, 98(1), 255-260. doi:10.1016/j.polymdegradstab.2012.10.003Parcheta, P., Głowińska, E., & Datta, J. (2020). Effect of bio-based components on the chemical structure, thermal stability and mechanical properties of green thermoplastic polyurethane elastomers. European Polymer Journal, 123, 109422. doi:10.1016/j.eurpolymj.2019.10942

Diodos emisores de luz para irradiación de plantas

Los recientes desarrollos conseguidos en el área de la iluminación con diodos emisores de luz (LEDs, cuando son inorgánicos, y OLEDs, cuando son orgánicos) resultan de gran interés en horticultura, al permitir manipular el espectro radiante que va a incidir sobre las plantas, con el objetivo de aumentar su producción o de generar determinados efectos fisiológicos, sobre todo en invernaderos. Puesto que los vegetales crecen mejor cuando son iluminados (irradiados) en las regiones roja y azul del espectro, resulta aconsejable sustituir los sistemas de iluminación fotosintética actuales, fundamentalmente mediante lámparas de descarga en gases (vapor de sodio a alta presión y, en menor medida, halogenuros metálicos), por LEDs comerciales que emiten separadamente en esas regiones o por OLEDs susceptibles de emisión conjunta. Además, estos dispositivos son más eficientes que las lámparas incandescentes (consumen mucha menor energía eléctrica y poseen una vida media de uso mucho más larga), no generan exceso de calor (y por tanto no dañan a plantas térmicamente sensibles), e incluso, en el caso de los LEDs rojos, repelen insectos, por lo que contribuyen a la disminución en el uso de agrotóxicos. En el presente artículo, se revisan las últimas contribuciones en Fitofotónica relacionadas con los diodos emisores de luz, se aporta la experiencia existente sobre la aplicación de LEDs a invernaderos y se divulga el estado de las investigaciones que algunos grupos de investigación estamos realizando sobre OLEDs emisores bien en el rojo o bien en las regiones del rojo y el azul

Metal Concentrations in e-Cigarette Liquid and Aerosol Samples:The Contribution of Metallic Coils

Supplemental Material is available online (https://doi.org/10.1289/EHP2175)Electronic cigarettes (e-cigarettes) generate an aerosol by heating a solution (e-liquid) with a metallic coil. Whether metals are transferred from the coil to the aerosol is unknown. Objective: Our goal was to investigate the transfer of metals from the heating coil to the e-liquid in the e-cigarette tank and the generated aerosol. Methods: We sampled 56 e-cigarette devices from daily e-cigarette users and obtained samples from the refilling dispenser, aerosol, and remaining e-liquid in the tank. Aerosol liquid was collected via deposition of aerosol droplets in a series of conical pipette tips. Metals were reported as mass fractions (μg/kg) in liquids and converted to mass concentrations (mg/m3) for aerosols. Results: Median metal concentrations (μg/kg) were higher in samples from the aerosol and tank vs. the dispenser (all p<0.001): 16.3 and 31.2 vs. 10.9 for Al; 8.38 and 55.4 vs. <0.5 for Cr; 68.4 and 233 vs. 2.03 for Ni; 14.8 and 40.2 vs. 0.476 for Pb; and 515 and 426 vs. 13.1 for Zn. Mn, Fe, Cu, Sb, and Sn were detectable in most samples. Cd was detected in 0.0, 30.4, and 55.1% of the dispenser, aerosol, and tank samples respectively. Arsenic was detected in 10.7% of dispenser samples (median 26.7 μg/kg) and these concentrations were similar in aerosol and tank samples. Aerosol mass concentrations (mg/m3) for the detected metals spanned several orders of magnitude and exceeded current health-based limits in close to 50% or more of the samples for Cr, Mn, Ni, and Pb. Conclusions: Our findings indicate that e-cigarettes are a potential source of exposure to toxic metals (Cr, Ni, and Pb), and to metals that are toxic when inhaled (Mn and Zn). Markedly higher concentrations in the aerosol and tank samples versus the dispenser demonstrate that coil contact induced e-liquid contamination.This study is supported by the Cigarette Restitution Fund (State of Maryland; grant PHPA-G2034). P.O. was supported by the Alfonso Martín Escudero Foundation (postdoctoral fellowship 2014). A.A. was supported by the American Heart Association Tobacco Regulation and Addiction Center (grant 1P50HL120163). A.N.A., M.H., and P.O. are supported by the National Institute of Environmental Health Sciences/National Institutes of Health (grant 5P30ES009089)

Associations of maternal arsenic exposure with adult fasting glucose and insulin resistance in the Strong Heart Study and Strong Heart Family Study

Experimental and prospective epidemiologic evidence suggest that arsenic exposure has diabetogenic effects. However, little is known about how family exposure to arsenic may affect risk for type 2 diabetes (T2D)-related outcomes in adulthood. We evaluated the association of both maternal and offspring arsenic exposure with fasting glucose and incident T2D in 466 participants of the Strong Heart Family Study. Total arsenic (ΣAs) exposure was calculated as the sum of inorganic arsenic (iAs) and methylated (MMA, DMA) arsenic species in maternal and offspring baseline urine. Median maternal ΣAs at baseline (1989-91) was 7.6 µg/g creatinine, while median offspring ΣAs at baseline (2001-03) was 4.5 µg/g creatinine. Median offspring glucose in 2006-2009 was 94 mg/dL, and 79 participants developed T2D. The fully adjusted mean difference (95% CI) for offspring glucose was 4.40 (-3.46, 12.26) mg/dL per IQR increase in maternal ΣAs vs. 2.72 (-4.91 to 10.34) mg/dL per IQR increase in offspring ΣAs. The fully adjusted odds ratio (95%CI) of incident T2D was 1.35 (1.07, 1.69) for an IQR increase in maternal ΣAs and 1.15 (0.92, 1.43) for offspring ΣAs. The association of maternal ΣAs with T2D outcomes were attenuated with adjustment for offspring adiposity markers. Familial exposure to arsenic, as measured in mothers 15-20 years before offspring follow-up, is associated with increased odds of offspring T2D. More research is needed to confirm findings and better understand the importance of family exposure to arsenic in adult-onset diabetes.This study was supported by the National Institute of EnvironmentalHealth Sciences, Unites States (P42ES010349, P30ES009089,R01ES028758, R01ES025216).N.T., P.F.-L., and A.N.-A. contributed to the preparation of researchdata and writing of the manuscript. N.T, M.J.S, A.D.-R., M.T.-P., M.G.-P., and A.N.-A. contributed to the statistical analysis. B.V.H., J.M., K.N.,J.G.U., and S.C. contributed as the primary investigators of the SHS andSHFS, and to the preparation of the research data. K.A.F. and W.G.contributed to the arsenic measurements in the SHS and SHFS partici-pants. A.N.-A. is the guarantor of this work and, as such, had full accessto all the data in the study and takes responsibility for the integrity ofthe data and the accuracy of the data analysis.S

Selenium and impaired physical function in US and Spanish older adults

Background: Selenium (Se) is a trace element with a narrow safety margin. Objectives: To evaluate the cross-sectional and longitudinal dose-response association between Se exposure and measures of impaired physical function and disability in older adults. Design: NHANES 2011–2014 cross-sectional (US, n = 1733, age ≥60 years) and Seniors-ENRICA-2 2017–2019 cross-sectional and longitudinal (Spain, n = 2548 and 1741, respectively, age ≥65 years) data were analyzed. Whole blood and serum Se levels were measured using inductively coupled plasma-mass spectrometry. Lowerextremity performance was assessed with the Short Physical Performance Battery, and muscle weakness with a dynamometer. Incident mobility and agility limitations, and disability in instrumental activities of daily living (IADL) were ascertained with standardized questionnaires. Analyses were adjusted for relevant confounders, including physical activity. Results across studies were pooled using random-effects meta-analysis. Results: Meta-analyzed odds ratios (95% confidence interval) per log2 increase in whole blood Se were 0.54 (0.32; 0.76) for weakness, 0.59 (0.34; 0.83) for impaired lower-extremity performance, 0.48 (0.31; 0.68) for mobility limitations, 0.71 (0.45; 0.97) for agility limitations, and 0.34 (0.12; 0.56) for disability in at least one IADL. Analyses for serum Se in NHANES showed similar results. Findings suggest the inverse association with grip strength is progressive below 140 μg/L (p-value for non-linear trend in the Seniors-ENRICA-2 study = 0.13), and above 140 μg/L (p-value for non-linear trend in NHANES = 0.11). In the Seniors-ENRICA-2 cohort, with a 2.2 year follow-up period, a doubling in baseline Se levels were associated with a lower incidence of weakness [odds ratio (95% confidence interval): 0.45 (0.22; 0.91)], impaired lower-extremity performance [0.63 (0.32; 1.23)], mobility [0.43 (0.21; 0.91)] and agility [0.38 (0.18; 0.78)] limitations. Discussion: In US and Spanish older adults, Se concentrations were inversely associated with physical function limitations. Further studies are needed to elucidate underlying mechanisms.Instituto de Salud Carlos III European Commission PI18/287 16/609State Secretary of R + D + I PID2019-108973RB-C21/C22European Social Fund (ESF) European Commissio

Urinary Metal Levels and Coronary Artery Calcification: Longitudinal Evidence in the Multi-Ethnic Study of Atherosclerosis (MESA)

Objective: Growing evidence indicates that exposure to metals are risk factors for cardiovascular disease (CVD). We hypothesized that higher urinary levels of metals with prior evidence of an association with CVD, including non-essential (cadmium , tungsten, and uranium) and essential (cobalt, copper, and zinc) metals are associated with baseline and rate of change of coronary artery calcium (CAC) progression, a subclinical marker of atherosclerotic CVD. Methods: We analyzed data from 6,418 participants in the Multi-Ethnic Study of Atherosclerosis (MESA) with spot urinary metal levels at baseline (2000-2002) and 1-4 repeated measures of spatially weighted coronary calcium score (SWCS) over a ten-year period. SWCS is a unitless measure of CAC highly correlated to the Agatston score but with numerical values assigned to individuals with Agatston score=0. We used linear mixed effect models to assess the association of baseline urinary metal levels with baseline SWCS, annual change in SWCS, and SWCS over ten years of follow-up. Urinary metals (adjusted to μg/g creatinine) and SWCS were log transformed. Models were progressively adjusted for baseline sociodemographic factors, estimated glomerular filtration rate, lifestyle factors, and clinical factors. Results: At baseline, the median and interquartile range (25th, 75th) of SWCS was 6.3 (0.7, 58.2). For urinary cadmium, the fully adjusted geometric mean ratio (GMR) (95%Cl) of SWCS comparing the highest to the lowest quartile was 1.51 (1.32, 1.74) at baseline and 1.75 (1.47, 2.07) at ten years of follow-up. For urinary tungsten, uranium, and cobalt the corresponding GMRs at ten years of follow-up were 1.45 (1.23, 1.71), 1.39 (1.17, 1.64), and 1.47 (1.25, 1.74), respectively. For copper and zinc, the association was attenuated with adjustment for clinical risk factors; GMRs at ten years of follow-up before and after adjustment for clinical risk factors were 1.55 (1.30, 1.84) and 1.33 (1.12, 1.58), respectively, for copper and 1.85 (1.56, 2.19) and 1.57 (1.33, 1.85) for zinc. Conclusion: Higher levels of cadmium, tungsten, uranium, cobalt, copper, and zinc, as measured in urine, were associated with subclinical CVD at baseline and at follow-up. These findings support the hypothesis that metals are pro-atherogenic factors.The Multi-Ethnic Study of Atherosclerosis (MESA) is supported by contracts 75N92020D00001, HHSN268201500003I, N01-HC-95159, 75N92020D00005, N01-HC-95160, 75N92020D00002, N01-HC-95161, 75N92020D00003, N01-HC-95162, 75N92020D00006, N01-HC-95163, 75N92020D00004, N01-HC-95164, 75N92020D00007, N01-HC-95165, N01-HC-95166, N01-HC-95167, N01-HC-95168 and N01-HC-95169 from the National Heart, Lung, and Blood Institute, and by grants UL1-TR-000040, UL1-TR-001079, and UL1-TR-001420 from the National Center for Advancing Translational Sciences (NCATS). This publication was developed under the Science to Achieve Results (STAR) research assistance agreements, No. RD831697 (MESA Air) and RD-83830001 (MESA Air Next Stage), awarded by the U.S Environmental Protection Agency (EPA). It has not been formally reviewed by the EPA. The views expressed in this document are solely those of the authors and the EPA does not endorse any products or commercial services mentioned in this publication. Dr. Maria Tellez-Plaza was supported by grants PI15/00071 and PI22/00029 from the Strategic Action for Health Research, Instituto de Salud Carlos III and the Spanish Ministry of Science and Innovation, and co-funded with European Funds for Regional Development (FEDER). The opinions and views expressed in this article are those of the authors and do not necessarily represent the official position of the Instituto de Salud Carlos III (Spain). Work in the authors? laboratories is also supported in part by NIH grants P42ES023716, P42ES010349, P42ES033719, P30ES009089, T32ES007322, R01ES029967, R01HL155576. The authors thank the other investigators, the staff, and the participants of the MESA study for their valuable contributions. A full list of participating MESA investigators and institutions can be found at http://www.mesa-nhlbi.org. This paper has been reviewed and approved by the MESA Publications and Presentations Committee.N

Second-generation colon capsule endoscopy compared with colonoscopy

Colon capsule endoscopy (CCE) represents a noninvasive technology that allows visualization of the colon without requiring sedation and air insufflation. A second-generation colon capsule endoscopy system (PillCam Colon 2) (CCE-2) was developed to increase sensitivity for colorectal polyp detection compared with the first-generation system. OBJECTIVE: To assess the feasibility, accuracy, and safety of CCE-2 in a head-to-head comparison with colonoscopy. DESIGN AND SETTING: Prospective, multicenter trial including 8 European sites. PATIENTS: This study involved 117 patients (mean age 60 years). Data from 109 patients were analyzed. INTERVENTION: CCE-2 was prospectively compared with conventional colonoscopy as the criterion standard for the detection of colorectal polyps that are >/=6 mm or masses in a cohort of patients at average or increased risk of colorectal neoplasia. Colonoscopy was independently performed within 10 hours after capsule ingestion or on the next day. MAIN OUTCOME MEASUREMENTS: CCE-2 sensitivity and specificity for detecting patients with polyps >/=6 mm and >/=10 mm were assessed. Capsule-positive but colonoscopy-negative cases were counted as false positive. Capsule excretion rate, level of bowel preparation, and rate of adverse events also were assessed. RESULTS: Per-patient CCE-2 sensitivity for polyps >/=6 mm and >/=10 mm was 84% and 88%, with specificities of 64% and 95%, respectively. All 3 invasive carcinomas were detected by CCE-2. The capsule excretion rate was 88% within 10 hours. Overall colon cleanliness for CCE-2 was adequate in 81% of patients. LIMITATIONS: Not unblinding the CCE-2 results at colonoscopy; heterogenous patient population; nonconsecutive patients. CONCLUSION: In this European, multicenter study, CCE-2 appeared to have a high sensitivity for the detection of clinically relevant polypoid lesions, and it might be considered an adequate tool for colorectal imaging

Anisotropy and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory

The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies $E>E_{th}=5.5\times 10^{19}$ eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at $E>E_{th}$ are heavy nuclei with charge $Z$, the proton component of the sources should lead to excesses in the same regions at energies $E/Z$. We here report the lack of anisotropies in these directions at energies above $E_{th}/Z$ (for illustrative values of $Z=6,\ 13,\ 26$). If the anisotropies above $E_{th}$ are due to nuclei with charge $Z$, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies

Wide-Geographic and Long-Term Analysis of the Role of Pathogens in the Decline of Pinna nobilis to Critically Endangered Species

A mass mortality event (MME) affecting the fan mussel Pinna nobilis was first detected in Spain in autumn 2016 and spread north- and eastward through the Mediterranean Sea. Various pathogens have been blamed for contributing to the MME, with emphasis in Haplosporidium pinnae, Mycobacterium sp. and Vibrio spp. In this study, samples from 762 fan mussels (necropsies from 263 individuals, mantle biopsies from 499) of various health conditions, with wide geographic and age range, taken before and during the MME spread from various environments along Mediterranean Sea, were used to assess the role of pathogens in the MME. The number of samples processed by both histological and molecular methods was 83. The most important factor playing a main role on the onset of the mass mortality of P. nobilis throughout the Mediterranean Sea was the infection by H. pinnae. It was the only non-detected pathogen before the MME while, during MME spreading, its prevalence was higher in sick and dead individuals than in asymptomatic ones, in MME-affected areas than in non-affected sites, and it was not associated with host size, infecting both juveniles and adults. Conversely, infection with mycobacteria was independent from the period (before or during MME), from the affection of the area by MME and from the host health condition, and it was associated with host size. Gram (-) bacteria neither appeared associated with MME.En prens

Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum