bluuebunny/crossref_metadata_2025_split huggingface dataset:
Octadecyl‐modified silica supports for metallocene catalyst applied in ethylene polymerization
Authors: Bernardes Arthur Alaim , Zarth Cintia Salomão Pinto , Gossler Fernanda Soares , Netto Antonio Marchi , Brambilla Rodrigo 
Published: September 2020

AbstractChemical modification of silica‐based supports is an alternative route for modulating the active sites of metallocene catalysts, presenting the potential to obtain polyethylenes with improved properties. Therefore, this work investigates the effect of octadecylsilane content in silica support on the behavior of resulting supported metallocene catalysts on ethylene polymerization. For this propose, a series of octadecyl‐modified silicas whit different amounts of octadecyl (ODS) groups were synthesized by a modified Stöber sol–gel method and then applied as supports for a metallocene catalyst. The supported metallocene catalysts were evaluated in ethylene polymerization and ethylene/1‐hexene copolymerization reactions. Besides, studies of the growth kinetics of polyethylene particles in a gas phase reactor were performed using videomicroscopy. The octadecylsilane content in the supports was in the range of 0.2 to 1.4 mmol g−1. DRIFTS and 13C CP/MAS NMR results showed a predominance of an all‐trans octadecyl chain conformation. SEM images showed spherical particle morphology for silicas having octadecylsilane content up to 0.6 mmol g−1. The supported catalysts presented activity in ethylene polymerization in the range of 1100–1900 kg PE molZr−1 h−1 bar−1. The surface polarity of the catalyst influenced the molar mass of the resulting polyethylene. The increase of the ODS content on the silica surface led to a supported catalyst with slower kinetic behavior in the gas phase, which might be attributed to the diffusive effects of the octadecyl layer on the catalyst surface.
Sulfonated polystyrene brushes grafted onto magnetic nanoparticles as recoverable catalysts for efficient synthesis of ethyl N‐phenylformimidate
Authors: Wang Xiaoying , Wang Lili , Sun Bingyan , Chu Xiaomeng , Xing Xuteng , Liu Shaojie , Tang Erjun 
Published: September 2020

AbstractIn this work, the sulfonated polystyrene brushes were grafted onto magnetic nanoparticles to obtain recoverable catalysts for efficient synthesis of ethyl N‐phenylformimidate. First, the surface modification of Fe3O4 with a particle size of about 10 nm was performed with the silane coupling agent of vinyl triethoxysilane (SG‐151) to obtain Fe3O4 with carbon–carbon double bonds on the surface (SG‐Fe3O4). Subsequently, SG‐Fe3O4, styrene (St) and chloromethyl styrene (CMSt) were polymerized to obtain the magnetic chloromethylated polystyrene sphere (SG‐Fe3O4@PS‐Cl) with core‐shell structure by solution copolymerization. Using St as monomer and SG‐Fe3O4@PS‐Cl as macromolecular initiator, the magnetic polystyrene brush of SG‐Fe3O4@PS‐PSt was obtained by activated regenerated electron transfer catalyst atom transfer radical polymerization. Finally, SG‐Fe3O4@PS‐PSt was sulfonated with sulfuric acid to form a magnetic sulfonated polystyrene brush of SG‐Fe3O4@PS‐PSH. SG‐Fe3O4@PS‐PSH was used as a recoverable acid catalyst to synthesize ethyl N‐phenylformimidate. Due to the high loading of the sulfonic acid group of this catalyst, its added amount was lower than other solid acids such as p‐toluenesulfonic acid. The results showed that the catalytic performance of SG‐Fe3O4@PS‐PSH was better than p‐toluenesulfonic acid and commercial macroporous sulfonic acid resin. The external magnetic field can directly recover SG‐Fe3O4@PS‐PSH, simplifying the recovery of catalyst and reducing the catalyst loss. After recycling, the yield of ethyl N‐phenylformimidate was not significantly decreased.
Polyvinyl alcohol/chitosan/carbon nanotubes electroactive shape memory nanocomposite hydrogels
Authors: Pirahmadi Pegah , Kokabi Mehrdad , Alamdarnejad Ghazaleh 
Published: September 2020

AbstractShape memory nanocomposite hydrogels are intelligent soft materials in which, the nanoparticles can impart desirable mechanical properties to the polymeric matrix. The main challenge is the capability to program from permanent to temporary shapes and vice versa under the direct and indirect thermal stimuli. In this work, carbon nanotubes (CNT) with a high modulus of 1 TPa, was used to mechanically reinforce polyvinyl alcohol (PVA) and polyvinyl alcohol/chitosan (PVA/Cs) hydrogel networks. Adding appropriate amount of conductor component enables the system to be electrically activated, which leads to achieving the original permanent shape without applying mechanical external force. The PVA/Cs/CNT hydrogel containing 0.25 wt% of CNT, showed electrical conductivity greater than 9 mS cm−1. Because of the presence of CNT, the shape memory behavior of PVA and PVA/Cs hydrogels was improved by 170 and 260%, respectively. The electroactive shape memory nanocomposite hydrogels exhibited complete recovery under indirect stimulation by generating Joule heating in the system.
Dams in the Amazon: The importance of maintaining free‐flowing tributaries for fish reproduction
Authors: Vasconcelos Lilian Paula , Alves Diego Corrêa , da Câmara Luís Fernando , Hahn Lisiane 
Published: September 2020

Abstract

Free‐flowing tributaries are important for the maintenance of fish diversity in dammed systems. In relation to the reproduction of fish species, the role of a free‐flowing tributary was evaluated and compared with that of a dammed tributary downstream of large dams in the Madeira River, one of the main tributaries of the Amazon River.
Two hypotheses were tested: (i) the densities of the ichthyoplankton differ between the dammed and the free‐flowing tributaries; and (ii) the free‐flowing tributary contributes a greater diversity of fish larvae species to the assemblage structure of the main stem than the dammed tributary.
Fish eggs and larvae were sampled at five sites: one in each tributary (Jamari – dammed – and Machado – free‐flowing) and three in the main stem (Madeira River), upstream and downstream from the mouth of each tributary.
Fitted Bayesian models showed that the densities both of eggs and larvae were more than twice as high in the free‐flowing tributary than in the dammed tributary. The results also indicated that the free‐flowing tributary makes a major contribution to the fish assemblage structure of the Madeira River, whereas the dammed tributary does not have a significant influence on the main stem assemblage structure.
The results demonstrate the importance of conservation and maintenance not only of the Machado River but also of other free‐flowing tributaries in dammed basins, especially those basins with high biodiversity, such as the Amazon. Moreover, this study helps inform the decision‐making process regarding the location of new dams, which is critical in fish diversity conservation.
Interactions Between Genome‐Wide Genetic Factors and Smoking Influencing Risk of Systemic Lupus Erythematosus
Authors: Cui Jing , Raychaudhuri Soumya , Karlson Elizabeth W. , Speyer Cameron , Malspeis Susan , Guan Hongshu , Sparks Jeffrey A. , Ni Hongru , Liu Xinyi , Stevens Emma , Williams Jessica N. , Davenport Emma E. , Knevel Rachel , Costenbader Karen H. 
Published: September 2020

ObjectiveTo identify interactions between genetic factors and current or recent smoking in relation to risk of developing systemic lupus erythematosus (SLE).MethodsFor the study, 673 patients with SLE (diagnosed according to the American College of Rheumatology 1997 updated classification criteria) were matched by age, sex, and race (first 3 genetic principal components) to 3,272 control subjects without a history of connective tissue disease. Smoking status was classified as current smoking/having recently quit smoking within 4 years before diagnosis (or matched index date for controls) versus distant past/never smoking. In total, 86 single‐nucleotide polymorphisms and 10 classic HLA alleles previously associated with SLE were included in a weighted genetic risk score (wGRS), with scores dichotomized as either low or high based on the median value in control subjects (low wGRS being defined as less than or equal to the control median; high wGRS being defined as greater than the control median). Conditional logistic regression models were used to estimate both the risk of SLE and risk of anti–double‐stranded DNA autoantibody–positive (dsDNA+) SLE. Additive interactions were assessed using the attributable proportion (AP) due to interaction, and multiplicative interactions were assessed using a chi‐square test (with 1 degree of freedom) for the wGRS and for individual risk alleles. Separate repeated analyses were carried out among subjects of European ancestry only.ResultsThe mean ± SD age of the SLE patients at the time of diagnosis was 36.4 ± 15.3 years. Among the 673 SLE patients included, 92.3% were female and 59.3% were dsDNA+. Ethnic distributions were as follows: 75.6% of European ancestry, 4.5% of Asian ancestry, 11.7% of African ancestry, and 8.2% classified as other ancestry. A high wGRS (odds ratio [OR] 2.0, P = 1.0 × 10−51 versus low wGRS) and a status of current/recent smoking (OR 1.5, P = 0.0003 versus distant past/never smoking) were strongly associated with SLE risk, with significant additive interaction (AP 0.33, P = 0.0012), and associations with the risk of anti‐dsDNA+ SLE were even stronger. No significant multiplicative interactions with the total wGRS (P = 0.58) or with the HLA‐only wGRS (P = 0.06) were found. Findings were similar in analyses restricted to only subjects of European ancestry.ConclusionThe strong additive interaction between an updated SLE genetic risk score and current/recent smoking suggests that smoking may influence specific genes in the pathogenesis of SLE.
A Novel RELA Truncating Mutation in a Familial Behçet’s Disease–like Mucocutaneous Ulcerative Condition
Authors: Adeeb Fahd , Dorris Emma R. , Morgan Niamh E. , Lawless Dylan , Maqsood Aqeel , Ng Wan Lin , Killeen Orla , Cummins Eoin P. , Taylor Cormac T. , Savic Sinisa , Wilson Anthony G. , Fraser Alexander 
Published: September 2020

ObjectiveMonogenic Behçet’s disease (BD)–like conditions are increasingly recognized and to date have been found to predominantly involve loss‐of‐function variants in TNFAIP3. This study was undertaken to identify genetic and pathobiologic mechanisms associated with a BD‐like mucocutaneous ulcerative syndrome and neuromyelitis optica (NMO) occurring in 3 generations of an Irish family (n = 5 cases and 5 familial controls).MethodsWhole‐exome sequencing was used to identify potential pathogenic variants in affected family members and determine segregation between affected and unaffected individuals. Relative v‐rel reticuloendotheliosis viral oncogene homolog A (RELA) expression in peripheral blood mononuclear cells was compared by Western blotting. Human epithelial and RelA−/− mouse fibroblast experimental systems were used to determine the molecular impact of the RELA truncation in response to tumor necrosis factor (TNF). NF‐κB signaling, transcriptional activation, apoptosis, and cytokine production were compared between wild‐type and truncated RELA in experimental systems and patient samples.ResultsA heterozygous cytosine deletion at position c.1459 in RELA was detected in affected family members. This mutation resulted in a frameshift p.His487ThrfsTer7, producing a truncated protein disrupting 2 transactivation domains. The truncated RELA protein lacks a full transactivation domain. The RELA protein variants were expressed at equal levels in peripheral mononuclear cells. RelA−/− mouse embryonic fibroblasts (MEFs) expressing recombinant human RELAp.His487ThrfsTer7 were compared to those expressing wild‐type RELA; however, there was no difference in RELA nuclear translocation. In RelA−/− MEFs, expression of RELAp.His487ThrfsTer7 resulted in a 1.98‐fold higher ratio of cleaved caspase 3 to caspase 3 induced by TNF compared to wild‐type RELA (P = 0.036).ConclusionOur data indicate that RELA loss‐of‐function mutations cause BD‐like autoinflammation and NMO via impaired NF‐κB signaling and increased apoptosis.
Information informing design: Information Science research with implications for the design of digital information environments
Authors: Makri Stephann 
Published: September 2020

AbstractThis debut curated “virtual special issue” of JASIST is on the theme of “information informing design.” It comprises several excellent scholarly research articles previously published in JASIST with important implications for the design of digital information environments. It covers articles that motivate the need for Information Science research to inform design and those that have empirically examined information‐related concepts such as information behavior, practices, interaction, and experience and, based on their findings, proposed recommendations or posed questions for design. This article argues that as JASIST exists at the intersection between information, systems, and users, it is natural to want to understand how people engage with information to inform design and, by doing so, Information Science research can build bridges between Information Science and computing disciplines and make contributions that transcend its discipline boundaries. It argues that Information Science research not only has the potential but also the duty to inform the design of future digital information environments.
Effects of radiative forcing on stable boundary layer development and diurnal temperature range over the central Heihe River Basin, China
Authors: Cao Bangjun , Zhu Lingzhi , Zheng Yijing , Du Bing , Kong Yuhui , Sun Xi , Wu Yao , Chen Caili , Zhang Yu 
Published: September 2020

AbstractUsing observations from the Heihe Watershed Allied Telemetry Experimental Research (HiWATER) datasets, the effect of radiative forcing on the development of the stable boundary layer (SBL) and diurnal temperature range (DTR) during summer over the central Heihe River Basin is investigated in this paper. Using a radiative temperature scale based on net longwave radiation (LWnet24), the DTR and the strength of SBL (δTS) are scaled, and the cycle and the year‐to‐year variability before and after scaling are analyzed. The results show that both DTR from air and surface temperatures have a significant correlation with LWnet24, and their correlation coefficients are different over different underlying surfaces. The cycle of DTR from 5‐m air temperature is similar with that of LWnet24. There is only a diurnal cycle in terms of 5‐m air temperature after scaling. Both the trends of the scaled DTR (DTRsc) and the scaled strength of SBL (δTSsc) increase with the growth time of the stable boundary layer (SBL) (τS). The period of τS is similar with that of DTRsc. τS is longer at the oasis site than at the Gobi site, which is related to the oasis effect. In addition, the greater the friction velocity, the smaller the DTRsc and δTSsc. The wind shear enables heat to disperse during SBL.
Predictors of Changes in Daily Activity in Transition‐Age Autistic Youth
Authors: Weiss Jonathan A. , Lai Jonathan K. Y. , Lee Vivian , Lunsky Yona 
Published: September 2020

Transitioning into adulthood is fraught with challenges for autistic youth. A greater understanding of the facilitators of community involvement in school and employment during this period is warranted. The current study examines changes in service need and receipt, and the stability of accessing daily structured activities, for autistic young adults over their transition period compared to adolescents and adults that did not enter the transition period. Baseline caregiver survey data were taken from the Canadian Autism Spectrum Disorders Alliance National Autism Needs Assessment Survey in 2014, and caregivers (n = 304) completed the same set of questions in 2017 about sociodemographic factors, clinical need, service receipt and typical weekday activities. Three cohorts were compared: (1) pretransition age youth, (2) transition‐age youth, and (3) young adults who were past transition age. Results suggest that transition‐age youth were found to have a unique set of priority service needs compared to pre transition‐age adolescent and to adult groups, and both transition‐age and adult groups had lower levels of priority service receipt compared to pretransition‐age adolescents. The transition‐age group experienced the greatest loss of structured weekday activity between time points, and were more likely than pretransition‐age adolescents to not have structured weekday activities at Time 2. A recovery of structured daily activity was not observed in young adults. Our results highlight the tumultuous nature of the transition period for autistic youth, which continues into adulthood, and the urgent need for supports during this time. Autism Res 2021, 14: 324–332. © 2020 The Authors. Autism Research published by International Society for Autism Research and Wiley Periodicals LLC. Lay SummaryThis research highlights that autistic young people who are transitioning to adulthood are at greatest risk of losing structured weekday activities, and that once in adulthood, many continue to struggle to obtain meaningful community engagement. These results can help guide the design of adolescent and young adult transition programs.
An optimization framework to identify key management strategies for improving biorefinery performance: a case study of winter barley production
Authors: Kar Saurajyoti , Riazi Bahar , Gurian Patrick L. , Spatari Sabrina , Adler Paul R. , Parton William J. 
Published: September 2020

AbstractThe selection of locations and practices for energy crops requires the economics to be planned and the carbon intensity of the fuel to be assessed. This study develops a framework for selecting near‐optimal cropland sites to minimize the cost to produce a targeted quantity of an energy crop, considering soil properties, fertilizer management, and spatio‐temporal trends in crop yield and soil emissions. DayCent, a biogeochemical model, simulates site‐level crop yield, and soil emissions. As a case study, this framework is applied to a 2.08 × 108 L year−1 capacity barley‐to‐ethanol biorefinery that selects cultivation sites from winter fallow cropland in the mid‐Atlantic region of the USA. The framework implements carbon crediting as per California's Low Carbon Fuel Standard. Our analysis finds the biorefinery's strategy on co‐products significantly influences its life‐cycle carbon intensity ranging between 0.74 gCO2e MJ−1 for all co‐product use and 59 gCO2e MJ−1 for no co‐product use. Coastal counties in Delaware show low soil emission and high yield, but higher transportation distances increase the carbon intensity of these distant croplands. When co‐products are used, the least intensive fertilizer management with fertilizer applications in spring is identified as the cost‐optimized choice for the biorefinery. It is also the option economically favored by growers, suggesting that detailed monitoring of these practices might not be needed to assure the adoption of low‐emission cultivation practices. However, the framework might demonstrate different results for other biofuel‐crop scenarios or different locations. The framework presented can assess the performance of a biorefinery prospectively and improve investors’ confidence in the biofuel industry. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd.
Prevalence of birth defects among infants with neonatal abstinence syndrome in Illinois, 2015–2016
Authors: Fornoff Jane , Sandidge Theresa 
Published: September 2020

AbstractBackgroundOpioid use has reached historically high levels across the United States and infants exposed during pregnancy are at risk of developing a drug withdrawal syndrome called neonatal abstinence syndrome (NAS). The prevalence of birth defects among Illinois infants exhibiting NAS has not been estimated.MethodsWe linked birth certificate data for Illinois‐resident infants born in Illinois in 2015 or 2016 to previously collected NAS and Adverse Pregnancy Outcome Reporting System birth defect data. We examined the prevalence of selected specific birth defects and of newborn infants with one or more of the National Birth Defects Prevention Network's (NBDPN) birth defects, comparing infants with and without NAS. We used logistic regression to estimate the odds ratio for having one or more NBDPN birth defects in infants with and without NAS, after adjusting for other risk factors.ResultsOf 302,043 Illinois‐resident births, 899 (3.0/1,000 live births) had NAS, and 4,250 (140.7/10,000 live births) had one or more NBDPN birth defect. Infants with an NBDPN birth defect were 1.9 (95% CI [1.3, 2.9]) times more likely to have developed NAS at delivery, and specifically, there was a higher prevalence of ventricular septal defect, club foot, and oral cleft, among infants with NAS when compared to those born without.ConclusionsElevated prevalence rates and odds ratios add to the growing evidence of an association between NAS and birth defects. Other studies have found similar associations between opioid exposure and the birth defects identified in this analysis.
Physical activity and gestational weight gain predict physiological and perceptual responses to exercise during pregnancy
Authors: Dobson Kayla L. , da Silva Danilo F. , Dervis Sheila , Mohammad Shuhiba , Nagpal Taniya S. , Adamo Kristi B. 
Published: September 2020

AbstractBackgroundExercise is known to improve the health of the pregnant woman and her child. Studies that have evaluated physiological parameters during prenatal exercise have conflicting results. Better understanding of these physiological responses can modify exercise prescriptions, safety, and monitoring strategies. We examined the association between age, prepregnancy body mass index (BMI), gestational weight gain (GWG), and physical activity (PA) levels, factors that may influence a change in physiological (HR, VO2 responses) and perceptual (RPE) responses to acute exercise throughout pregnancy.MethodsTwenty‐two healthy pregnant women (31.4 ± 3.7 years) performed a Submaximal incremental Walking Exercise Test (SWET). Early‐ (13–18 weeks), mid‐ (24–28 weeks), and late‐pregnancy (34–37 weeks) were compared. VO2 (L/min; ml/kg/min), HR (bpm), and RPE were collected at the end of each test stage. PA was determined by accelerometry. We associated PA levels, GWG, prepregnancy BMI, and age with HR, RPE, and VO2 responses.ResultsHR, RPE, and absolute VO2 were higher in late‐pregnancy compared to earlier time points (p < .05; η2 = 0.299–0.525). Regression models were built for HR (all time points), RPE (early‐ and late‐pregnancy), and VO2 (L/min; late‐pregnancy). HR (late‐pregnancy) was predicted by time in vigorous PA, GWG, age, and prepregnancy BMI (r2 = 0.645; SEE = 5.84). RPE (late‐pregnancy) was predicted by sedentary time, GWG, prepregnancy BMI, and age (r2 = 0.662; SEE = 1.21).ConclusionPhysiological/perceptual responses were higher in late‐pregnancy compared to other time points and associated with combined PA, GWG, prepregnancy BMI, and age. These findings can be used to modify exercise prescriptions and designs for future PA interventions in pregnant women.