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Novel mixed antioxidants composed of antioxidant IPPD and lanthanum (La) complex were added as a filler to form natural rubber (NR) composites. By mechanical testing, Fourier transform infrared spectroscopy with attenuated total reflectance (FTIR-ATR) and thermogravimetric analysis (TGA), a string of data, including the mechanical properties, the variation of internal groups and the thermal and thermo-oxidative decompositions of NR, was presented in this data article. The data accompanying its research article [1] studied the thermo-oxidative aging properties of NR in detail. The density function theoretical (DFT) calculations were also used as an assistant to study the thermo-oxidative aging mechanism of NR. The data revealed that this new rare-earth antioxidant could indeed enhance the thermo-oxidative aging resistance of NR, which is associated with its different function mechanism from that of the pure antioxidant IPPD.

The use of conductive polymer composites (CPCs) as strain sensors has been widely investigated. A wide range of strain sensitivities and high repeatability are vital for different applications of CPCs. In this study, the relations of the conductive filler network and the strain-sensing behavior and electrical stability under fatigue cycles were studied systematically for the first time based on the conductive polymethylvinylsiloxane (PMVS) composites filled with both carbon nanotubes arrays (CNTAs) and carbon black (CB). It was proved that the composites could be fabricated with large strain-sensing capability and a wide range of strain sensitivities by controlling the volume ratio of CNTA/CB and their amounts. Additionally, the CNTA/CB/PMVS composite with 3 vol % content of fillers showed high sensitivity (GF is 10 at 60% strain), high repeatability (the relative standard deviation (RSD) of the max R/R0 value is 3.58%), and electrical stability under fatigue cycles (value range of R/R0 is 1.62 to 1.82) at the same time due to the synergistic effects of the dual conductive network of CNTAs and CB. This could not be achieved by relying on a single CNTA or CB conductive network. This study may provide guidance for the preparation of high performance CPCs for applications in strain sensors.

The semi-hyperbolic (SHPB) die with and possibly without wall lubrication has been proposed as a device for measuring the elongational viscosity of polymeric fluids. Using numerical simulation under the condition of complete wall slip, it was found for two polyethylenes (LDPE and LLDPE) that the calculated elongational viscosity values agreed well with strain-averaged values, , obtained from independent measurements in stretching type rheometers. This is in agreement with the original hypothesis of Everage and Ballman (E-B). Numerical simulations showed that the Baird and Huang (B-H) approach for calculating , which accounts for the shear stress due to geometric considerations in the presence of complete slip, agreed with data better than did the E-B approach. Numerical simulations using varying degrees of wall slip indicated that reasonable values of could be obtained using the B-H approach with wall slip levels which could be most likely reached using a coating such as a flouroelastomer. The numerical simulations provided an explanation as to why the elongational viscosity values determined in the SHPB die for resins such as LDPE, which are extensional-strain hardening, are less sensitive to wall slip than non-strain-hardening resins such as LLDPE.

The coronavirus disease 2019 (COVID‐19) pandemic has casted a huge impact on global public health and the economy. In this challenging situation, older people are vulnerable to the infection and the secondary effects of the pandemic and need special attention. To evaluate the impacts of COVID‐19 on older people, it is important to balance the successful pandemic control and active management of secondary consequences. These considerations are particularly salient in the Asian context, with its diversity among countries in terms of sociocultural heritage, healthcare setup and availability of resources. Thus, the Asian Working Group for Sarcopenia summarized the considerations of Asian countries focusing on responses and difficulties in each country, impacts of health inequity related to the COVID‐19 pandemic and proposed recommendations for older people, which are germane to the Asian context. More innovative services should be developed to address the increasing demands for new approaches to deliver healthcare in these difficult times and to establish resilient healthcare systems for older people. Geriatr Gerontol Int 2020; 9999: n/a–n/a. [ABSTRACT FROM AUTHOR]

Research on Chinese American women's cervical cancer screening behaviours is limited and there are few studies that examine factors associated with obtaining regular Pap tests. The purpose of this study was to use the transtheoretical model ( TTM) as a framework to examine correlates of Pap testing and stages of change. Chinese American women ( N = 121) were recruited to complete a cross-sectional, self-report survey. Survey items assessed stages of change, self-efficacy, perceived benefits and barriers, and demographic variables including screening and family history for cervical cancer. Eighty-one per cent of women reported that they had ever had a Pap test. Most participants were in the maintenance stage (55%), with 10% in each action and pre-contemplation, 8% in contemplation, 1% in preparation and 16% in the relapse stage. Women in the action/maintenance stage were more likely to be older, married and have a higher education level. Women in the action/maintenance stage had significantly lower perceived barrier scores compared to women in both the contemplation/preparation and pre-contemplation/relapse stages. Findings partially support the use of TTM for cervical cancer screening among this population and indicate the importance of perceived barriers. Results may inform interventions to increase screening rates among Chinese American women. [ABSTRACT FROM AUTHOR]

ABSTRACT The compressive stress relaxation tests of butadiene rubber (BR) at different thermo-oxidative aging temperatures were carried out. Fourier transform infrared spectroscopy with attenuated total reflectance (FTIR-ATR) was used to observe the variations of internal groups before and after the thermo-oxidative aging. Magnetic resonance-crosslink density (MR-XLD) spectroscopy was used to measure the crosslink densities. The results showed the compressive stress relaxation of BR during thermo-oxidative aging was dominated by chemical reactions: crosslinking, chain scission, and oxidation. Then an empirical model and an amendatory standard linear solid (SLS) model were put forward to describe the compressive stress relaxation behavior of BR. Both models fitted the data well. The SLS model, based on the aging mechanism of BR, not only made up the disadvantages of the empirical model, but also considered the changes of intrinsic viscosity (η) during the thermo-oxidative aging of BR. The SLS model showed that the thermo-oxidative aging of BR was mainly dominated by the crosslinking and oxidation reactions. This research proposes the amendatory SLS model and has important significance for study the stress relaxation behavior of crosslinked rubbers during thermo-oxidative aging. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44630. [ABSTRACT FROM AUTHOR]

NASADEM is a near-global elevation model that is being produced primarily by completely reprocessing the Shuttle Radar Topography Mission (SRTM) radar data and then merging it with refined ASTER GDEM elevations. The new and improved SRTM elevations in NASADEM result from better vertical control of each SRTM data swath via reference to ICESat elevations and from SRTM void reductions using advanced interferometric unwrapping algorithms. Remnant voids will be filled primarily by GDEM3, but with reduction of GDEM glitches (mostly related to clouds) and therefore with only minor need for secondary sources of fill. [ABSTRACT FROM AUTHOR]

Natural rubber (NR) composites highly filled with nano-α-alumina (nano-α-Al2O3) modified in situ by the silane coupling agent bis-(3-triethoxysilylpropyl)-tetrasulfide (Si69) were prepared. The effects of various modification conditions and filler loading on the properties of the nano-α-Al2O3/NR composites were investigated. The results indicated that the preparation conditions for optimum mechanical (both static and dynamic) properties and thermal conductivity were as follows: 100 phr of nano-α-Al2O3, 6 phr of Si69, heat-treatment time of 5 min at 150°C. Furthermore, two other types of fillers were also investigated as thermally conductive reinforcing fillers for the NR systems: (1) hybrid fillers composed of 100 phr of nano-α-Al2O3 and various amounts of the carbon black (CB) N330 and (2) nano-γ-Al2O3, the particles of which are smaller than those of nano-α-Al2O3. The hybrid fillers had better mechanical properties and dynamic performance with higher thermal conductivity, which means that it can be expected to endow the rubber products serving under dynamic conditions with much longer service life. The smaller sized nano-γ-Al2O3 particles performed better than the larger-sized nano-α-Al2O3 particles in reinforcing NR. However, the composites filled with nano-γ-Al2O3 had lower thermal conductivity than those filled with nano-α-Al2O3 and badly deteriorated dynamic properties at loadings higher than 50 phr, both indicating that nano-γ-Al2O3 is not a good candidate for novel thermally conductive reinforcing filler. POLYM. COMPOS., 37:771-781, 2016. © 2014 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

A combined study of experimental and molecular dynamics (MD) simulation methods is presented for hindered phenol AO-80/nitrile-butadiene rubber/poly(vinyl chloride) (AO-80/NBR/PVC) composites with different AO-80 contents to establish the microstructure-damping property relations. MD simulation found that the AO-80/NBR/PVC composite (abbreviated as AO-80/NBVC) with an AO-80 content of 99 phr had the largest hydrogen bonds (H-bonds) and highest binding energy, indicating a good compatibility between NBR and AO-80 and good damping performance of AO-80/NBVC composites. Experimental results from SEM, DSC, and DMA were in good agreement with the MD simulation results. The tensile test results showed that the AO-80/NBVC composite with an AO-80 content of 99 phr had high tensile strength because of the strong H-bonds of the composites and the disintegration and reintegration of the H-bonds. The MD simulation technique proves to be a promising tool for the design and prediction of high damping properties of advanced composites in a microscopic view. [ABSTRACT FROM AUTHOR]

Aims To (a) assess the HIV/ AIDS knowledge and sources of HIV/sexually transmitted infection ( STI) information among sexually abstinent college students in China; (b) examine whether constructs from the transtheoretical model ( TTM) are applicable to this study population regarding condom use intention; and (c) evaluate the association between genders and TTM constructs, and HIV/ AIDS knowledge. Background Chinese college students are vulnerable to HIV and other STIs. Strategies targeting abstinent students are more cost-effective than providing treatment for diseases. Methods We surveyed 390 students enrolled in two universities in China. Data were collected from June 2009 to March 2010. Results Only 11% and 24% were aware of HIV spread by infected semen and of the protective effects of condom use against HIV. The mass media were major sources of HIV/ STI information. Individuals who had higher levels of self-efficacy and reported more perceived benefits and fewer perceived barriers were more likely to be in TTM contemplation stage of condom use than those in precontemplation. Females were less likely to discuss HIV/ STIs through online chat or email with strangers than males. Individuals who had higher levels of self-efficacy and reported more perceived benefits and fewer perceived barriers were more likely to be in TTM contemplation stage of condom use than those in precontemplation. Conclusion Sexually abstinent college students in China may be more likely to transition from precontemplation to contemplation if they know the benefits of condom use for the prevention of HIV/ STIs and if they learn to successfully minimize potential barriers related to condom use. [ABSTRACT FROM AUTHOR]

In this paper, graphene oxide/styrene-butadiene rubber (GO/SBR) composites with complete exfoliation of GO sheets were prepared by aqueous-phase mixing of GO colloid with SBR latex and a small loading of butadiene-styrene-vinyl-pyridine rubber (VPR) latex, followed by their co-coagulation. During co-coagulation, VPR not only plays a key role in the prevention of aggregation of GO sheets but also acts as an interface-bridge between GO and SBR. The results demonstrated that the mechanical properties of the GO/SBR composite with 2.0 vol.% GO is comparable with those of the SBR composite reinforced with 13.1 vol.% of carbon black (CB), with a low mass density and a good gas barrier ability to boot. The present work also showed that GO-silica/SBR composite exhibited outstanding wear resistance and low-rolling resistance which make GO-silica/SBR very competitive for the green tire application, opening up enormous opportunities to prepare high performance rubber composites for future engineering applications. [ABSTRACT FROM AUTHOR]

Distributional analysis of river discharge time series is an important task in many areas of hydrological engineering, including optimal design of water storage and drainage networks, management of extreme events, risk assessment for water supply, and environmental flow management, among many others. Having diverging moments, heavy-tailed power law distributions have attracted widespread attention, especially for the modeling of the likelihood of extreme events such as floods and droughts. However, straightforward distributional analysis does not connect well with the complicated dynamics of river flows, including fractal and multifractal behavior, chaos-like dynamics, and seasonality. To better reflect river flow dynamics, we propose to carry out distributional analysis of river flow time series according to three "flow seasons" : dry, wet, and transitional. We present a concrete statistical procedure to partition river flow data into three such seasons and fit data in these seasons using two types of distributions, power law and lognormal. The latter distribution is a salient property of the cascade multiplicative multifractal model, which is among the best models for turbulence and rainfall. We show that while both power law and lognormal distributions are relevant to dry seasons, river flow data in wet seasons are typically better fitted by lognormal distributions than by power law distributions. [ABSTRACT FROM AUTHOR]

Purpose. The aim of this study is to explore whether/which job coach factors were significantly associated with the community-based employment service (CBES) programme outcome measures in Taiwan. Method. This study used the 2003-2005 CBES programme for People with Disabilities Database in Taipei City in Taiwan (n = 3924) to do a secondary data analysis using hierarchical multiple linear regression. Results. This study found that 'occurrences of the services provided by the job coaches' variable was definitely the dominant predictor and explained additional 19.6% and 27.8% of the variances of annual salary and annual working month outcome measures, respectively. In addition, among six composition variables of 'occurrences of the services provided by the job coaches', 'occurrences of follow-up guidance', 'occurrences of intensive guidance', and 'occurrences of consultation before interviews with employer/director of human resources' were more powerful than the other three in predicting outcomes. Conclusions. Job coach factors in this study were significantly correlated with CBES programme outcome measures for people with disabilities in Taiwan after controlling for the socio-demographic variables. It indicates that the more inputs in the people with disabilities made by job coaches equates to better outcomes in this Taiwan case study. [ABSTRACT FROM AUTHOR]

To explore the correlates for nonuse of condoms and the factors that affect stages of change for regular condom use among college students in Taiwan. Cross-sectional, quantitative survey design. A total of 996 college students were recruited from two universities in Northern Taiwan. Questionnaires collected data on demographic information, condom use, HIV/AIDS knowledge, confidence in using condoms in different situations, and perceived benefits and barriers to using condoms. The common reasons for not using condoms were trust in the partner (21.30%), partner dislike for condoms (19.49%), and perception of low risk (18.77%). Most sexually active students (52.4%) were in the earliest 2 stages of readiness to change (i.e., precontemplation, contemplation). Participants in action/maintenance were (a) 43.4% less likely to show a high knowledge score, (b) 4.08 times more likely to present high self-efficacy, and (c) 2.24 times more likely to be more religious than those in contemplation/preparation. Among a highly literate group, college students, condom use is inconsistent and readiness to change is not imminent. This study reveals that preventive steps targeted at young adults should address other concerns related to condom use such as trust in partners and the alleged appeal of unprotected sex. [ABSTRACT FROM AUTHOR]

Heat treatment is an important process to facilitate the fixation of titanium dioxide particles on the surface of various substances. The interfacial binding of titanium dioxide particles is critical in affecting the photocatalytic activities of the functionalised material. Hence, the effect of heat treatment on the self-cleaning properties was investigated. Moreover, fibres physical and mechanical properties form one of the criteria to determine the usability of the fibres. Therefore, in order to widen the application and enhance the feasibility of the self-cleaning functionalisation process, the effect of titanium dioxide formulation on the low stress mechanical properties of the fibres was studied. [ABSTRACT FROM AUTHOR]

BACKGROUND: Trigger finger is most common in the ring finger, but the reason for this is not known. We hypothesized that the compliance of the A1 pulley might be one of the factors responsible for this phenomenon. The purpose of this study was therefore to compare the compliance of the normal A1 pulley of the thumb, index, middle, ring and little fingers using human cadavers. METHODS: Eight normal thumbs, index, middle, ring and little fingers from eight fresh frozen human hand cadavers were used in this experiment. The compliance of the A1 pulley was measured by the resistance when passing a tapered metal rod through the A1 pulley. The slopes of the linear region of radial force/increasing area ratio curve were calculated and analyzed. FINDINGS: The mean slope of the linear region of the radial force/increasing area ratio curve was significantly different among the five digits (p<0.05). Post hoc analysis indicated that the mean slope for the middle finger A1 pulleys was larger than the thumb and little finger A1 pulleys (p<0.05). INTERPRETATION: The findings did not support our clinical hypothesis that A1 pulley stiffness would parallel the relative frequency of trigger finger by digit. [ABSTRACT FROM AUTHOR]

BACKGROUND: Clinical diagnosis and classification of trigger fingers is traditionally based on physical examinations and certain obvious symptoms. However, it might lack quantitative evidence to describe the different graded trigger digits. This study provides quantitative evidence of kinematics and functional differences among different graded trigger fingers based on Froimson's classification. METHODS: Forty-seven patients with fifty-five trigger fingers and graded twenty-three, eleven, and twenty-one fingers as grades II, III, and IV, respectively. The QuickDASH questionnaire evaluated the subject's self-perception of hand symptoms and functions. The study measured maximal workspace of the fingertip motion and range of motion of the finger joints during an assigned tendon-gliding task using an electromagnetic tracking device. In addition, R(alpha), defined as the ratio range of angular acceleration during finger extension to the range during finger flexion of each joint, quantified the triggering effect. FINDINGS: The QuickDASH score results show that functional performances have significant differences among three grades (P<0.05). Workspace, range of motion of proximal interphalangeal joint and R(alpha) of proximal interphalangeal and distal interphalangeal joint of trigger fingers also significantly differ among three grades (P<0.05). These findings quantitatively show that trigger fingers in different impairment levels have different kinematics and functional performances. INTERPRETATION: The results serve as evidence-based knowledge for clinics. The more practical and immediate application of this study would be to facilitate the assessment, design and execution of rehabilitation for patients with trigger fingers. [ABSTRACT FROM AUTHOR]

Aims: To explore sexual behaviours and condom use and differences in specific items of perceived benefits and barriers to condoms using the Transtheoretical Model (TTM) stages among college students in southern Taiwan. Background: The TTM suggests that individuals in the action or maintenance stage exhibit higher levels of perceived benefits and lower levels of perceived barriers related to condom use than people in the precontemplation, contemplation or preparation stage. Methods: This was a descriptive, cross-sectional design with cluster sampling among college students from two universities in southern Taiwan. Participants completed self-administered questionnaires, including demographic data, Sexual History and Condom Use Scale and Condom Use Decisional Balance Scale. Results: Of the 279 participants, 57% were sexually active, of these only 11.9% used condoms consistently. Respondents in the TTM stage of action/maintenance perceived greater benefits in relation to feeling more responsible ( P = 0.031) and protecting their partners as well as themselves ( P = 0.028), and perceived more barriers in believing that using condom needs to rely on partner's cooperation ( P = 0.046) than participants in precontemplation. Participants in precontemplation and contemplation perceived more barriers related to worry about making their partner angry if condoms were used than those in action/maintenance ( P = 0.008). Conclusion: Low levels of condom use among Taiwanese college students remain a significant public health concern. HIV prevention programmes for college students in Taiwan may be enhanced if they incorporate readiness to change and perceived benefits and barriers. Future research should include a larger sample with diverse groups. [ABSTRACT FROM AUTHOR]

HIV infection rates in Taiwan have been growing at nearly 15% per year since 1997, one of the fastest rates in Asia. Little is known about the knowledge, attitudes, and sexual behaviors of college-age young adults in Taiwan. This study assessed the knowledge, attitudes, sources of HIV information, and behaviors related to HIV among college students; it also explored variables associated with the knowledge and attitudes about HIV among college students in Taiwan. Data were collected through a self-administered questionnaire from 132 Taiwanese college students enrolled in two private universities. Study results showed that fewer than half (48.5%) of the participants were aware that HIV could be spread through infected semen, and, nearly a quarter of participants believed that HIV could be contracted through mosquito bites, toilet seats, or swimming pools. Only 29.5% reported ever having had sex. This research provides additional insights that may be used to develop effective HIV prevention strategies in Taiwan. [ABSTRACT FROM AUTHOR]