bluuebunny/crossref_metadata_2025 huggingface dataset:
Mining-induced violent resistance: the case of salt mining near Keta lagoon
Authors: Atta-Quayson Alhassan , Baidoo Amina H.
Published: December 2020

There has been an upsurge in mining-induced violent resistance within the vicinity of Keta lagoon in Ghana that questions the legitimacy of ongoing large-scale salt production by Kensington Salt Industries Ltd. Between 2013 and 2017, there was a series of violent protests and clashes at Adina and adjoining communities at the eastern banks of Keta lagoon, leading to deaths and to destruction of the company’s property and equipment. The upsurge of mining-induced violent resistance in Keta follows the displacement of thousands of indigenes and growing state preference for large-scale projects in the salt sector. The article thus questions the credibility of the company’s permits and calls on relevant state agencies to engage Kensington and the affected communities to address the outlined factors responsible for the resistance and conflict. This must be done in accordance with the minerals and mining policy framework as well as regional and continental policy initiatives that the government has committed to.
Horses for courses. The roles of IPE and Global Public Policy in global energy research
Authors: Goldthau Andreas , Sitter Nick
Published: December 2020

Although IPE and GPP overlap conceptionally and empirically, there is a case for keeping GPP and IPE analytically distinct. To simplify: GPP tells us why we need international regimes for energy, while IPE tells us why we only have incomplete ones. Although many scholars draw on both sets of literatures, the two approaches to the study of energy market, regulation and politics entail asking different types of questions based on distinct theories and assumptions. The central propositions in this article are that i) in a rapidly changing world of energy scholars from both camps need to be aware of and open to insights from the other school; ii) that the distinction between market-focused liberal scholars on one hand and security-oriented or realist scholars on the other is increasingly important; and iii) that although IPE and GPP scholars can fruitfully accommodate insights from each others literature, the two approaches to the study of energy policy are best valued by their own analytical contribution – even as we grapple with new, cross-cutting issues such as the geopolitics and geo-economics of global energy transitions.
Velocity preserving transfer between highly excited atomic states: black body radiation and collisions
Authors: de Aquino Carvalho J C , Maurin I , Failache H , Bloch D , Laliotis A
Published: December 2020

We study the excitation redistribution from cesium 7P1/2 or 7P3/2 to neighboring energy levels by black body radiation (BBR) and inter atomic collisions using pump-probe spectroscopy inside a vapor cell. At low vapor densities we measure redistribution of the initial, velocity-selected, atomic excitation by BBR. This redistribution preserves the selected atomic velocities allowing us to perform high resolution spectroscopy of the 6D → 7F transitions. This transfer mechanism could also be used to perform sub-Doppler spectroscopy of the cesium highly-excited nG levels. At high densities we observe interatomic collisions redistributing the excitation within the cesium 7P fine and hyperfine structure. We show that 7P redistribution involves state-changing collisions that preserve the initial selection of atomic velocities. These redistribution mechanisms can be of importance for experiments probing high lying excited states in dense alkali vapor.
Hydrogen sulfide gas sensor based on TiO2–ZnO composite sensing membrane-coated no-core fiber
Authors: Feng Wenlin , Yang Xiaozhan , He Zhiyong , Liu Min
Published: December 2020

A novel hydrogen sulfide (H2S) gas sensor based on multimode interference is proposed and presented. The sensor is constructed by a 30 mm no-core fiber (NCF) and two 30 mm thin-core fibers (TCFs). The first part of the TCF is excited by the high-order modes, in the second part of TCF, the basic core and high-order modes are coupled to the last single-mode fiber, which can induce inter-mode interference. Titanium dioxide–zinc oxide (TiO2–ZnO) composite film is coated on the outside surface of the NCF by the dip-coating method. The experimental results indicate that there is a good linear relationship between the wavelength shift and the different H2S gas concentrations. The sensor has a sensitivity of 21.26 pm ppm−1 in the gas range of 0–50 ppm H2S. In addition, the TiO2–ZnO composite sensing membrane has good selectivity for H2S gas. The response and recovery times are about 90 s and 115 s, respectively. The sensor has the advantages of simple structure, high sensitivity, easy manufacture and could be used in toxic H2S gas monitoring.
Deep-level impurities hyperdoped diamond: a first-principles calculations
Authors: Dong Xiao , Wang Tianxing , An Yipeng , Wang Yongyong
Published: December 2020

A hyperdoped diamond material is engineered by first-principles calculations in this work. Several deep-level elements, such as S, Se, Te, Co, Au, V, Ni, are chosen as dopants in the diamond. The formation energy results show that the substitutional configuration of the dopants is more stable than the interstitial ones. The substitutional configurations of chalcogen dopants (S, Se, Te) can introduce a nearly filled intermediate band (IB) in the upper half of the bandgap of the diamond. The substitutional configurations of several transition metals, such as Co, Au, V, Ni, and Cu, can form partially filled IB(s) near the center of the bandgap, which is more appropriate than that formed by the chalcogens. The dielectric function results indicate that all of these deep-level elements can lead to the sub-bandgap absorption and the absorption range and intensity vary dramatically with different dopants. Among these dopants, Co, Au, and Cu exhibit a special strong sub-bandgap absorption in a longer wavelength range, which would make the material to be an excellent photoelectric device. With reducing the concentration of the transition metal dopants, the IBs in the bandgap are narrower and tend to separate from each other and the sub-bandgap absorptions reduce sharply. Our conclusions imply that the photoelectric properties of the novel diamond material would be modulated by changing the dopant types and concentrations.
A pneumatic piston-released rapid compression machine for chemical kinetics studies at elevated pressure and low to intermediate temperatures
Authors: Nyong Oku Ekpenyong , Woolley Robert
Published: December 2020

This work presents a pneumatically operated piston released rapid compression machine (PRRCM) designed at the University of Sheffield that introduces a new set of pneumatic systems to lock/release the piston from its initial position. It is pneumatically operated to compress gas mixture to an adiabatically thermodynamic state and stopped hydraulically. The range of compression ratios of the facility is between 4.4 and 20. The end of compressed gas temperature, T
c and pressure, P
c obtained within the facility is approximately 1000 K and 22 bar respectively. The performance of the Sheffield piston released rapid compression machine (SHEF-PRRCM) facility has been characterised to ensure a high level of fidelity of experimental data over a range of test conditions. The performance test was conducted for a nonreactive test using nitrogen and argon, the result demonstrated a repeatable pressure trace. Repeatability test for the reactive mixtures was also demonstrated. Further study on ignition characteristics of aviation fuel (Jet A-1) and Banner NP1014 known as Bannersol in SHEF-PRRCM was conducted over T
c of 723 K ⩽ T
c ⩽ 884 K, P
c = 6 and 10 bar at ϕ = 0.75 and 1.0. The influence of pressure, temperature and equivalence ratio was seen on the oxidation of Jet A-1 and Bannersol. The results showed that Bannersol displayed a negative temperature coefficient behaviour and has higher reactivity than Jet A-1. Besides, a comparative analysis of the current facility with other facilities in literature was carried out, the result showed a fair deviation of the current data from literature and these could be attributed to the inherent non-ideality of heat transfer effects in different rapid compression machine and fairly slight differences in the condition tested. This work has demonstrated the competence of the current facility to carry out further studies on combustion and validation of the chemical kinetics of hydrocarbon fuels.
Structural, optical, photocatalytic, and optoelectronic properties of Zn2SnO4 nanocrystals prepared by hydrothermal method
Authors: Qi Yifang , Meador William E , Xiong Jian , Abbaszadeh Mahsa , Thirumala Rooban Venkatesh K G , Delcamp Jared H , Kundu Santanu , Hill Glake Alton , Dai Qilin
Published: December 2020

Zn2SnO4 (ZTO) nanocrystals are extensively studied in various fields. However, size-dependent ZTO nanocrystals are still challenging to understand their structural, optical, photocatalytic, and optoelectronic properties. ZTO nanocrystals are synthesized by a facile hydrothermal reaction method. The structural properties of the synthesized ZTO nanocrystals are studied by x-ray diffraction and transmission electron microscope. The sizes of the ZTO nanocrystals are controlled by the pH values of the precursor and the molar ratios of the Zn:Sn in the starting materials. ZTO nanocrystals with the small size of 6 nm and large size of 270 nm are obtained by our method. The Eu3+ ions are doped into ZTO nanocrystals to probe size-dependent Eu doping sites, which shows significant potential applications in light emitting diode phosphors. Moreover, the photocatalytic activity of ZTO nanocrystals on rhodamine (RhB) decoloration are investigated, and the results show that 6 nm ZTO nanocrystals show better performance in the photocatalytic decoloration of RhB compared to 270 nm nanocrystals. Most importantly, we design and fabricate optoelectronic devices to detect IR light based on our nanocrystals and a self-prepared NIR cyanine dye. The device based on small sized ZTO nanocrystals exhibits better device performance under 808 nm IR light compared to that of the large sized ZTO nanocrystals. We believe this work represents ZTO size-dependent properties in term of structural, optical, photocatalytic, and optoelectronic properties as a multifunctional material.
Deposition amount effects on the microstructure of ion-beam-sputtering grown Mn0.03Ge0.97 quantum dots for spintronic applications
Authors: Li Yahui , Li Chen , Tong Haochen , Chen Tao , Li Guangyang , Huang Shizhe , Tang Shumin , Qiu Feng , Yang Jie , Sun Tao , Yang Yu , Wang Chong
Published: December 2020

Here, a relative simpler and lower cost method, ion beam sputtering deposition was applied to fabricate diluted magnetic Mn
x
Ge1−x
quantum dots (QDs). The effects of Ge–Mn co-deposition amount on the morphology and crystallization of Mn0.03Ge0.97 QDs were investigated systematically by employing the atomic force microscopy and Raman spectroscopy techniques. It can be seen that the morphology, density, and crystallinity of Mn0.03Ge0.97 QDs exhibit unique evolution processes with the increase of Ge–Mn co-sputtering amount. The optimal deposition amount for realizing well size-uniform, large-aspect-ratio, and high-density QDs is also determined. The unique evolution route of diluted magnetic semiconductor QDs and the amount of co-sputtering are also discussed sufficiently.
Two-dimensional carbon nitride C6N nanosheet with egg-comb-like structure and electronic properties of a semimetal
Authors: Bafekry A , Shahrokhi M , Shafique A , Jappor H R , Shojaei F , Feghhi S A H , Ghergherehchi M , Gogova D
Published: December 2020

In this study, the structural, electronic and optical properties of theoretically predicted C6N monolayer structure are investigated by means of Density Functional Theory-based First-Principles Calculations. Phonon band dispersion calculations and molecular dynamics simulations reveal the dynamical and thermal stability of the C6N single-layer structure. We found out that the C6N monolayer has large negative in-plane Poisson’s ratios along both X and Y direction and the both values are almost four times that of the famous-pentagraphene. The electronic structure shows that C6N monolayer is a semi-metal and has a Dirac-point in the BZ. The optical analysis using the random phase approximation method constructed over HSE06 illustrates that the first peak of absorption coefficient of the C6N monolayer along all polarizations is located in the IR range of spectrum, while the second absorption peak occurs in the visible range, which suggests its potential applications in optical and electronic devices. Interestingly, optically anisotropic character of this system is highly desirable for the design of polarization-sensitive photodetectors. Thermoelectric properties such as Seebeck coefficient, electrical conductivity, electronic thermal conductivity and power factor are investigated as a function of carrier doping at temperatures 300, 400, and 500 K. In general, we predict that the C6N monolayer could be a new platform for study of novel physical properties in two-dimensional semi-metal materials, which may provide new opportunities to realize high-speed low-dissipation devices.
Reproducibility and Validity of a Semiquantitative Food Frequency Questionnaire in Men Assessed by Multiple Methods
Authors: Al-Shaar Laila , Yuan Changzheng , Rosner Bernard , Dean Stefanie B , Ivey Kerry L , Clowry Catherine M , Sampson Laura A , Barnett Junaidah B , Rood Jennifer , Harnack Lisa J , Block Jason , Manson JoAnn E , Stampfer Meir J , Willett Walter C , Rimm Eric B
Published: December 2020

Among 626 participants of the Men’s Lifestyle Validation Study (2011–2013), we evaluated the validity and reproducibility of a self-administered 152-item semiquantitative food frequency questionnaire (SFFQ) using two 7-day dietary records (7DDRs), 4 Automated Self-Administered 24-hour dietary recalls (ASA24s), four 24-hour urine samples, 1 doubly labeled water measurement (repeated in 104 participants), and 2 fasting blood samples, collected over 15 months. Compared with 7DDRs, SFFQs underestimated energy intake, macronutrients, and sodium intake but overestimated some micronutrients. The mean of the Spearman correlation coefficients was 0.66 (range, 0.38–0.88) between 46 energy-adjusted nutrients estimated from 7DDRs and the final SFFQ, deattenuated for within-person variation in the 7DDRs. These deattenuated correlations were similar using ASA24s as the comparison. Relative to biomarkers, SFFQs underestimated energy, sodium, and protein intakes, as well as the sodium:potassium ratio. The energy-adjusted correlations between the final SFFQ and the biomarkers were slightly lower than the correlations between the SFFQ and 7DDRs. Using the method of triads to calculate validity coefficients, the median validity coefficient between SFFQ and true intake was 0.65 and 0.69 using 7DDRs and ASA24s, respectively, as the third method. These data indicate that this SFFQ provided reasonably valid estimates for a wide range of nutrients when evaluated by multiple comparison methods.
Initiator Types and the Causal Question of the Prevalent New-User Design: A Simulation Study
Authors: Webster-Clark Michael , Ross Rachael K , Lund Jennifer L
Published: December 2020

New-user designs restricting to treatment initiators have become the preferred design for studying drug comparative safety and effectiveness using nonexperimental data. This design reduces confounding by indication and healthy-adherer bias at the cost of smaller study sizes and reduced external validity, particularly when assessing a newly approved treatment compared with standard treatment. The prevalent new-user design includes adopters of a new treatment who switched from or previously used standard treatment (i.e., the comparator), expanding study sample size and potentially broadening the study population for inference. Previous work has suggested the use of time-conditional propensity-score matching to mitigate prevalent user bias. In this study, we describe 3 “types” of initiators of a treatment: new users, direct switchers, and delayed switchers. Using these initiator types, we articulate the causal questions answered by the prevalent new-user design and compare them with those answered by the new-user design. We then show, using simulation, how conditioning on time since initiating the comparator (rather than full treatment history) can still result in a biased estimate of the treatment effect. When implemented properly, the prevalent new-user design estimates new and important causal effects distinct from the new-user design.
The Clinical Course of Coronavirus Disease 2019 in a US Hospital System: A Multistate Analysis
Authors: Mody Aaloke , Lyons Patrick G , Vazquez Guillamet Cristina , Michelson Andrew , Yu Sean , Namwase Angella Sandra , Sinha Pratik , Powderly William G , Woeltje Keith , Geng Elvin H
Published: December 2020

There are limited data on longitudinal outcomes for coronavirus disease 2019 (COVID-19) hospitalizations that account for transitions between clinical states over time. Using electronic health record data from a hospital network in the St. Louis, Missouri, region, we performed multistate analyses to examine longitudinal transitions and outcomes among hospitalized adults with laboratory-confirmed COVID-19 with respect to 15 mutually exclusive clinical states. Between March 15 and July 25, 2020, a total of 1,577 patients in the network were hospitalized with COVID-19 (49.9% male; median age, 63 years (interquartile range, 50–75); 58.8% Black). Overall, 34.1% (95% confidence interval (CI): 26.4, 41.8) had an intensive care unit admission and 12.3% (95% CI: 8.5, 16.1) received invasive mechanical ventilation (IMV). The risk of decompensation peaked immediately after admission; discharges peaked around days 3–5, and deaths plateaued between days 7 and 16. At 28 days, 12.6% (95% CI: 9.6, 15.6) of patients had died (4.2% (95% CI: 3.2, 5.2) had received IMV) and 80.8% (95% CI: 75.4, 86.1) had been discharged. Among those receiving IMV, 35.1% (95% CI: 28.2, 42.0) remained intubated after 14 days; after 28 days, 37.6% (95% CI: 30.4, 44.7) had died and only 37.7% (95% CI: 30.6, 44.7) had been discharged. Multistate methods offer granular characterizations of the clinical course of COVID-19 and provide essential information for guiding both clinical decision-making and public health planning.
Plural Governmentalities: Governing Welfare Fraud in Sweden
Authors: Stenström Anders
Published: December 2020

The criminalization of welfare and policing has often been analysed as being indicative of the global rise of a neoliberal political agenda. The current paper examines how governmental power is organized to govern investigators responsible for policing welfare in Sweden. Using empirical illustrations from the Swedish case, it shows how multiple governmental logics are enacted in the context of a broader political will to crack down on welfare fraud. Specifically, it demonstrates how so-called control investigators are tasked to realize a neoconservative agenda. To this end, these investigators are themselves governed using an amalgam of neoliberal and bureaucratic rationalities and technologies. The paper argues that examinations of the articulation of multiple governmental rationalities offer one route for thinking intelligibly about power and criminalization and by extension about the limits of neoliberal rule.
Hidden victims: the gendered data gap of violent crime
Authors: Cooper Kerris , Obolenskaya Polina
Published: December 2020

The official measure of violent crime, reported by the Office for National Statistics using the Crime Survey for England and Wales (CSEW), excludes sexual offences and neglects the self-completion survey data which more reliably captures sexual and domestic violence. In failing to include these gendered forms of violence, the official picture of who is most at risk of violence is skewed, suggesting men are at greater risk than women. This research re-estimates who is most at risk of violence, incorporating sexual and domestic violence and analysing trends in violence between 2005 and 2018 by gender. The findings challenge official statistics, revealing that women were at greater risk of violence than men in 2018.
NFIA and NFIB function as tumour suppressors in high-grade glioma in mice
Authors: Chen Kok-Siong , Lynton Zorana , Lim Jonathan W C , Robertson Thomas , Gronostajski Richard M , Bunt Jens , Richards Linda J
Published: December 2020

Nuclear factor one (NFI) transcription factors are implicated in both brain development and cancer in mice and humans and play an essential role in glial differentiation. NFI expression is reduced in human astrocytoma samples, particularly those of higher grade, whereas over-expression of NFI protein can induce the differentiation of glioblastoma cells within human tumour xenografts and in glioblastoma cell lines in vitro. These data indicate that NFI proteins may act as tumour suppressors in glioma. To test this hypothesis, we generated complex mouse genetic crosses involving six alleles to target gene deletion of known tumour suppressor genes that induce endogenous high-grade glioma in mice, and overlaid this with loss of function Nfi mutant alleles, Nfia and Nfib, a reporter transgene and an inducible Cre allele. Deletion of Nfi resulted in reduced survival time of the mice, increased tumour load and a more aggressive tumour phenotype than observed in glioma mice with normal expression of NFI. Together, these data indicate that NFI genes represent a credible target for both diagnostic analyses and therapeutic strategies to combat high-grade glioma.
Reinfection With SARS-CoV-2: Implications for Vaccines
Authors: Cohen Jeffrey I , Burbelo Peter D
Published: December 2020

Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become pandemic and the duration of protective immunity to the virus is unknown. Cases of persons reinfected with the virus are being reported with increasing frequency. At present it is unclear how common reinfection with SARS-CoV-2 is and how long serum antibodies and virus-specific T cells persist after infection. For many other respiratory virus infections, including influenza and the seasonal coronaviruses that cause colds, serum antibodies persist for only months to a few years and reinfections are very common. Here we review what is known about the duration of immunity and reinfection with coronaviruses, including SARS-CoV-2, as well as the duration of immunity to other viruses and virus vaccines. These findings have implications for the need of continued protective measures and for vaccines for persons previously infected with SARS-CoV-2.
Bioaerosol Sampling for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in a Referral Center with Critically Ill Coronavirus Disease 2019 (COVID-19) Patients March–May 2020
Authors: Lane Morgan A , Brownsword Erik A , Babiker Ahmed , Ingersoll Jessica M , Waggoner Jesse , Ayers Marie , Klopman Matthew , Uyeki Timothy M , Lindsley William G , Kraft Colleen S
Published: December 2020

Background

Previous research has shown that rooms of patients with coronavirus disease 2019 (COVID-19) present the potential for healthcare-associated transmission through aerosols containing severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). However, data on the presence of these aerosols outside of patient rooms are limited. We investigated whether virus-containing aerosols were present in nursing stations and patient room hallways in a referral center with critically ill COVID-19 patients.

Methods

Eight National Institute for Occupational Safety and Health BC 251 2-stage cyclone samplers were set up throughout 6 units, including nursing stations and visitor corridors in intensive care units and general medical units, for 6 h each sampling period. Samplers were placed on tripods which held 2 samplers positioned 102 cm and 152 cm above the floor. Units were sampled for 3 days. Extracted samples underwent reverse transcription polymerase chain reaction for selected gene regions of the SARS-CoV-2 virus nucleocapsid and the housekeeping gene human RNase P as an internal control.

Results

The units sampled varied in the number of laboratory-confirmed COVID-19 patients present on the days of sampling. Some of the units included patient rooms under negative pressure, while most were maintained at a neutral pressure. Of 528 aerosol samples collected, none were positive for SARS-CoV-2 RNA by the estimated limit of detection of 8 viral copies/m3 of air.

Conclusions

Aerosolized SARS-CoV-2 outside of patient rooms was undetectable. While healthcare personnel should avoid unmasked close contact with each other, these findings may provide reassurance for the use of alternatives to tight-fitting respirators in areas outside of patient rooms during the current pandemic.
Death of a child and the risk of atrial fibrillation: a nationwide cohort study in Sweden
Authors: Wei Dang , Olofsson Tristan , Chen Hua , Janszky Imre , Fang Fang , Ljung Rickard , Yu Yongfu , Li Jiong , László Krisztina D
Published: December 2020

Aims

The role of psychological stress in the aetiology of atrial fibrillation (AF) is unclear. The death of a child is one of the most severe sources of stress. We aimed to investigate whether the death of a child is associated with an increased risk of AF.

Methods and results

We studied parents with children born during 1973–2014 included the Swedish Medical Birth Register (n = 3 924 237). Information on death of a child, AF and socioeconomic, lifestyle and health-related covariates was obtained through linkage to nationwide population and health registers. We examined the link between death of a child and AF risk using Poisson regression. Parents who lost a child had a 15% higher risk of AF than unexposed parents [incidence rate ratio (IRR) and 95% confidence intervals (CI): 1.15 (1.10–1.20)]. An increased risk of AF was observed not only if the child died due to cardiovascular causes [IRR (95% CI): 1.35 (1.17–1.56)], but also in case of deaths due to other natural [IRR (95% CI): 1.15 (1.09–1.21)] or unnatural [IRR (95% CI): 1.10 (1.02–1.19)] causes. The risk of AF was highest in the 1st week after the loss [IRR (95% CI): 2.87 (1.44–5.75)] and remained 10–40% elevated on the long term.

Conclusions

Death of a child was associated with a modestly increased risk of AF. Our finding that an increased risk was observed also after loss of a child due to unnatural deaths suggests that stress-related mechanisms may also be implicated in the development of AF.
Identification of Sarcopenia in Amazonian Elderly
Authors: Faber Myrian
Published: December 2020

This research has applied the SARCF to identify the presence of sarcopenia in 236 women aged 66.27 ± 5.76 year from Amazonas, who have attended activities aimed at the elderly. The SARCF analyzes five objective variables for assessing sarcopenia, related to the functional pattern (strength, walking, sitting and getting up from a chair, climbing stairs and falls). Functional patterns are scored to independence = 0, some dependence = 1 and a lot of difficulty or functional disability = 2. Regarding falls during the year; none = 0, ≥ 1 ≤ 3 = 1 and ≥ 4 = 2. Values ≥0≤4, suggest absence of sarcopenia, ≥4≤10 sarcopenia. Results has revealed 100 (42.37%) elderly women without difficulties to carry objects weighing 5 kilos, 130 (55.31%) have presented some difficulty and 6 (2.55%) couldn’t do it so. As for walking, 108 (45.76%) haven’t needed help, 128 (54.23%) have needed some help. Regarding to sit and get up from a chair, 17 (7.20%) haven’t needed help, 218 (92.37%) have needed help and 1 (0.42%) couldn’t do it. Climb stairs 17 (7.20%) haven’t needed help, 173 (73.30%) have needed help and 46 (19.49%) couldn’t do it so. Concerning about falls, 150 (63.55%) elderly women haven’t fallen, 57 (24.15%) have fallen between one and three times and 29 (12.29%) have fallen more times. The final SARCF score has revealed a sarcopenia prevalence in 54% of the surveied population; CI = 0.30, CORREL = 0.90 (54.05%) sarcopenic; 6 (2.55%) pre-sarcopenia, 24 (18.9%) sarcopenia, 24 (18.9%) severe sarcopenia.
What Role Do Different Types of Social Support Play in Life Satisfaction Among Korean Older Adults in Retirement?
Authors: Woo Jihee , Choi Hyojin
Published: December 2020

Individuals are taking more responsibility for their retirement. However, economic stress generated by inadequate planning may pose a grave threat to well-being in retirement. Drawing on stress theory, this study examined how different types of social support mediate the relationship between economic stress and life satisfaction. We used the data from the 2013 and 2014 Korean Retirement and Income Study. Our sample was restricted to older Korean adults in retirement 55 to 96 years of age who were head of household (N=1,672). Confirmatory factor analysis was used to evaluate the measurement model for six latent constructs: 1) economic stress; 2) emotional support; 3) informational support; 4) instrumental support; 5) appraisal support; 6) life satisfaction. Structural equation modeling (SEM) was used to test this hypothesized model. The results revealed that both measurement model (CFI=0.985, TLI=0.983, RMSEA=0.036, SRMR=0.035) and structural model (CFI=0.978, TLI=0.984, RMSEA=0.030, SRMR=0.039) fit the data well. Standardized results from the SEM model adjusting for sociodemographic variables showed that economic stress directly predicted life satisfaction (β=-0.39, p<0.001) and two of four social support types directly predicted life satisfaction (instrumental support β=0.29, p<0.001; appraisal support β=0.25, p=0.004). Analyses demonstrated that economic stress may lead to lower levels of life satisfaction directly and indirectly through its effect on instrumental (β=-0.07, p<0.001) and appraisal support (β=-0.04, p=0.013). These findings will help inform policymakers and institutions of the need to alleviate economic stress and increase particular types of support with potentially more serious impact on the well-being of older adults in retirement.
Associations Between Hearing Loss, Loneliness, and Social Isolation: A Systematic Review
Authors: Suen Jonathan , Shukla Aishwarya , Goman Adele , Price Carrie , Lin Frank , Reed Nicholas
Published: December 2020

Hearing loss is highly prevalent among older adults, as is occurrences of loneliness and social isolation. Both loneliness and social isolation are also associated with insidious outcomes such as earlier mortality from all-causes and higher prevalence of chronic comorbidities. The purpose of this review is to synthesize published investigations that report on the associations between hearing loss with loneliness and social isolation. A systematic search through PubMed, Embase, CINAHL Plus, PsycINFO, and the Cochrane Library identified an initial total of 2495 references. Two independent reviewers screened articles for inclusion, with a third reviewer adjudicating. Studies published in English of older adults with hearing loss that also assessed loneliness and/or social isolation using a validated measure were included. Investigators used a modified Newcastle-Ottawa Scale (NOS) to appraise study quality. A final total of 14 articles were included in the review. The majority (12/14) were cross-sectional in design. Assessment methods were varied across hearing status, loneliness, and social isolation. Despite this heterogeneity, most multivariable adjusted investigations revealed that hearing loss was significantly associated with higher risks for both phenomena. Several studies also revealed this association to vary across gender, with women showing a stronger association than men. Our findings indicate that hearing loss is associated with both loneliness and social isolation, which have important implications for the cognitive and psychosocial health of older adults. Future investigations should examine possible underlying mechanisms of these relationships, as well as the efficacy of interventions through aural rehabilitation programs in addressing loneliness and social isolation.
The Effects of Grandchild Care on Mental Health Among Chinese Elderly: The Mediating Effects of Social Networks
Authors: Tang Dan , Qiu Jie , Zhang Kun
Published: December 2020

Using the data of 2014 baseline survey of the China Longitudinal Aging Social Survey (CLASS), which provides a sample of older Chinese who had grandchild younger than 18 years old, this study examines the associations among grandchild care, social networks, and depressive symptoms among Chinese older adults. The older adults are divided into three groups basing on the frequency of their behaviors of taking care of grandchildren. The three groups are ‘no care, providing care occasionally, providing care frequently’. The mediating and moderating effects of social networks between grandchild care and depressive symptoms are tested. Results show that older adults who provide grandchild care report superior social networks and better mental health than those who don’t provide grandchild (reference group). After controlling the related variables, the older adults who provide grandchild occasionally benefit more than those who take care of grandchild frequently. Grandchild care is related to larger social networks, and the social networks are fully mediating the association between grandchild care and depressive symptoms.
The Impact of Taking Care of Grandchildren on Health Outcomes in Japanese Community-Dwelling Elderly
Authors: Fujiwara Yoshinori , Nonaka Kumiko , Kuraoka Masataka , Murayama Sachiko , Nemoto Yuta , Murayama Hiroshi , Murayama Yoh , Kobayashi Erika
Published: December 2020

Taking care of grandchildren may provide health benefits to older adults due to keeping their social roles and feeling more generative; however, we have scarce knowledge of the relationships in Asian countries. This study addressed this question in older Japanese. The data was obtained from a two-year follow-up mail survey conducted in 2016 on 3,116 randomly selected older Japanese, aged 65-84 years, living in a metropolitan area. The main outcome was deterioration of health assessed by the Self-Rated Health (SRH), WHO-5, and Instrumental Activities of Daily Living (IADLs), defined as decline in 1 or more points obtained after 2 years of follow-up. The frequency of taking care of grandchildren was assessed as every day, 4-6 days per week, 1-3 days per week, 1-3 days per month, several days per year, and none. A multiple linear regression examined the impact of taking care of grandchildren as a predictor of protection of decline in SRH, WHO-5 and IADLs. The models were adjusted for confounding factors. Of 1,561 who responded to the follow-up survey, 959 people had grandchildren at baseline. The subjects had a mean age of 73.2±5.3 years, and mean scores of SRH:2.1±0.6; WHO-5;16.1±5.3, IADLs; 4.9±0.6 (higher scores represent higher evaluation). The higher frequency of taking care of grandchildren were longitudinally associated with less decline in SRH, WHO-5, and IADLs (standardized partial regression coefficient, β=-0.090, p=0.013; β =-0.023, p=0.547; β =-0.107, p=0.008, respectively). In conclusion, taking care of grandchildren might be a protective factor of comprehensive and functional health deterioration.
Considering LTSS Through the Lenses of Social Construction of Target Populations: Theory and Neoliberalism
Authors: Buckley Tommy , Cox Carole , Doron Israel (Issi)
Published: December 2020

The global increase of the older population has led to a greater demand for long term support services (LTSS) that address their rights and needs for care. However, policies among countries remain diverse with varying options, services, and recognition of human rights. This study applies the Social Construction of Target Population (SCTP) theory which relates to the perception of older adults and Neoliberalism, a political theory associated with policies of economic privatization, deregulation, and free market activity to the analysis of LTSS systems. As an example, in the United States, the concept of Successful Aging, conflicts with the need for LTSS while present Neoliberal policies that stress minimal government intervention and regulation contribute to little support for any comprehensive LTSS policy. This paper reviews existing policies in 7 countries, representing diverse regions, cultures, and political systems as a means of understanding the relationship of SCTP and Neoliberalism to LTSS. Highlighting the roles that these theories may play can assist in understanding and developing systems that meet the rights and health care needs of older adults.
Cortisol Responses to a Laboratory Challenge: The Moderating Role of Cognitive Performance
Authors: Grimm Elise , Agrigoroaei Stefan
Published: December 2020

Recent theoretical and empirical studies have considered higher cognitive performance as a protective factor with respect to reactivity, recovery and habituation to acute stressors. The goal of our study was to examine the individual role of inhibition, working memory, processing speed, reasoning, and category fluency in the regulation of the cortisol response to a laboratory challenge. Younger, middle-aged, and older participants (N =109, aged 22-84, M=55.90, SD=16.35) were invited to a laboratory session comprising a driving simulation and a set of cognitive tasks. At least one week in advance, baseline cognitive performance was measured using the Brief Test of Adult Cognition by Telephone (BTACT). Throughout the lab session, five saliva samples were taken, which allowed for the computation of a global measure of cortisol release (area under the curve (AUC)). Cortisol AUC was regressed on the individual BTACT cognitive tests, while controlling for age, sex, education, body mass index, physical activity, and time since awakening. The results revealed that inhibition and working memory significantly accounted for the cortisol response. These associations remained significant when other factors such as smoking, caffeine consumption, and medication use were included as covariates. The contributions of reasoning and speed of processing approached significance. Our findings contribute to the emerging evidence that cognitive functioning modulates stress responses to acute stressors. The findings are discussed in the context of cognitive interventions with transfers and implications for stress processes and healthy aging.
Developmental Trajectory of Theory-of-Mind Decline in Older Adults
Authors: Yow W Quin , Li Xiaoqian , Lee Jiawen
Published: December 2020

Theory-of-Mind (ToM) is critical to individual social competence and mental health across the lifespan (Frith, 2008). Though it is often discussed as one broad construct, ToM abilities can be viewed as following a developmental trajectory: from early emotion recognition and gaze following to more advanced inferences about others’ beliefs, perspectives, and intentions (Hutchins et al., 2012). Despite current literature suggesting that ToM abilities may be impaired in late adulthood, there is no consensus regarding whether ToM abilities are differentially affected by age. In this study, we examined younger adults (N=18, aged 19-30) and older adults (N=13, aged 58-76) on their ToM competence across three levels of ToM abilities: Early-ToM (e.g., recognizing a happy face), Basic-ToM (e.g., perspective-taking and false-belief reasoning), and Advanced-ToM (e.g., inferring second-order emotion and false belief). All participants completed a Theory-of-Mind Task Battery consisting of three subscales that assessed the three levels of ToM, where participants viewed vignettes and answered questions about the protagonists’ feelings and beliefs. Overall, younger adults outperformed older adults on the battery, F(1,29)=7.34, p=.011. However, a significant interaction between age and ToM levels (p=.010) revealed that Early and Advanced ToM (ps>.25) were not as affected by age as Basic ToM (p=.007). Older adults have difficulty in inferring others’ perspectives/beliefs while their attributions of emotion and higher-order false beliefs are relatively preserved compared to the younger adults. These findings provide important insights into the impact of age on various levels of ToM and could help inform early detection of ToM decline in normal aging.
Is Volunteering an Equalizer? A Quasi-Experimental Study Using Propensity Score Analysis
Authors: Kim Seoyoun , Halvorsen Cal
Published: December 2020

Formal volunteering in later life has been extolled as beneficial for both physical and mental health. However, research points to potential selection bias, in that older adults with key advantages, such as higher wealth, are more likely to volunteer and reap its benefits. As such, we test two competing propositions: Volunteering may act as an equalizer if it benefits the health of the least wealthy the most, or it may further exacerbate disparities if it benefits the health of the wealthiest the most. To that end, we analyzed data from the 2012 and 2014 waves of the Health and Retirement Study (N≈15,000). First, we used relevant covariates (e.g., sociodemographic characteristics, informal volunteering, and health) in 2012 to predict volunteering in 2014, developing the propensity score weights from these results. We then performed several regression analyses to assess the influence of volunteering on self-reported health and depressive symptoms among the general population (ATE) and volunteers themselves (ATT), while comparing the findings for the highest and lowest wealth quintiles. We found that volunteering enhanced self-reported health and reduced depressive symptoms. Further, those in the highest quintile experienced significantly fewer depressive symptoms from volunteering while those in the lowest quintile did not, albeit with no significant differences between the two coefficients. The study enhances the nuanced understanding of volunteering and health while suggesting that unmeasured factors felt strongest among the least wealthy—such as financial distress, discrimination, or lack of organizational support—may attenuate the benefits of voluntary activity.
Neural Inhibition Task Elicits Age-Associated Changes in Prefrontal Cerebral Oxygenation
Authors: Salzman Talia , Rahman Tabassum , Polskaia Nadia , St-Amant Gabrielle , Vallejo Diana Tobón , Lajoie Yves , Fraser Sarah
Published: December 2020

Certain cognitive tasks, such as those involving inhibition, can influence an older adult’s dual-tasking ability more than others. This study aimed to manipulate cognitive task difficulty to evaluate age-associated differences in brain activity and behaviour during walking. Nineteen younger (M=21.3, SD=3.9) and 20 older (M=71.8, SD=6.4) adults completed four cognitive-auditory tasks: simple reaction time (SRT; processing speed), Go-no-Go (GNG; neural inhibition), N-back (NBK; working memory) and Double number sequence (DNS; working memory) with or without self-paced walking. Trials took place under single cognitive (SC), single motor (SM) and dual-task (walking with a cognitive task; DT) conditions. Throughout each condition, cerebral oxygenation changes (ΔHbO2) in the prefrontal cortex were acquired using functional near-infrared spectroscopy (fNIRS). Behavioural measures including response time (ms), accuracy (%) and gait speed (m/s) were also calculated. Repeated measures ANOVAs revealed that OAs exhibited greater ΔHbO2 than YAs in the left hemisphere during the GNG inhibition task (p = 0.04). Activation in the right hemisphere also increased compared to the left during DNS DT (p = 0.05). Response times increased with increasing task difficulty and YAs were faster than OAs during NBK SC (p = 0.09). Neural findings revealed age-associated changes in prefrontal activation at the GNG inhibition difficulty level. Behavioural results indicated poorer performance with increasing task difficulty including slower response times in OAs. Moreover, gait speed and accuracy only decreased within task and difficulty. Therefore, understanding the neural and behavioural changes across task difficulty may help monitor cognitive decline and distinguish normal aging from disease states.
Implementation Approaches to Strengthen a Food Insecurity Intervention for Older Adults in an Emergency Department
Authors: Aylward Aileen , Platts-Mills Timothy , Wardlow Liane , Sullivan Conor , Anderson Jessa Engelberg , Morris Andrea
Published: December 2020

Food insecurity is prevalent among older adults, negatively impacts health, and may increase healthcare utilization. Emergency Departments (ED) are an important site of care for older adults. However, the feasibility of screening for food insecurity in EDs is unknown. We assessed the feasibility of implementing a screening and referral process to identify and address food insecurity among older adults in the ED and then monitored progress to overcome barriers to implementation. We developed a semi-structured interview (SSI) guide using the Consolidated Framework for Implementation Research. Prior to implementation, ED staff with diverse clinical backgrounds participated in SSIs. SSIs were analyzed using rapid analysis. Before and during implementation, we engaged hospital leadership to refine the screening and referral process. During implementation, we identified barriers through periodic reflections with staff, observing screenings, and reviewing Electronic Medical Record (EMR) data. Staff agreed that food insecure older adults would benefit from community services. Nursing Assistants (NA) were identified as key implementers. ED leaders expressed concerns about regulatory compliance, EMR integration, and NA scope of work, which were addressed. During implementation, barriers included competing priorities, lack of knowledge, and discomfort with the topic of food insecurity. Stakeholder input and reviewing EMR data led to adaptations including modifying criteria for referral and embedding training into NA orientation. Leadership and staff supported food insecurity interventions but identified several concerns. Steps to facilitate implementation included identifying staff to screen, EMR integration, and building staff efficacy. Reviewing screening data and soliciting stakeholder feedback enabled ongoing adaptations that strengthened implementation.
Feeling Older and Constrained: Synergistic Influences of Control Beliefs and Subjective Age on Cognition
Authors: Cerino Eric , O’Brien Erica , Almeida David
Published: December 2020

Control beliefs are important correlates of cognitive health and aging. In addition, how old or young one feels is a self-perception of aging that may play a role in understanding control-cognition associations. We explored whether subjective age moderates associations among control beliefs and cognitive performance using data from the third wave of the national Midlife in the United States study. The analytic sample comprised of 2,621 adults aged 39–93 (Mage=64.06, SD=11.15; 55.51% female) that completed measures of control (mastery, perceived constraints), subjective age (how old you feel most of the time), and cognition (executive function, episodic memory) via telephone administration. Hierarchical regression analyses were conducted to examine whether mastery, perceived constraints, and subjective age were associated with cognitive performance, adjusting for chronological age, gender, education, marital status, and self-rated health. For executive function, there was a significant perceived constraints by subjective age interaction. Higher levels of perceived constraints were associated with worse executive function (Est.=-0.05, SE=0.01, p<.001), and this association was amplified among those with relatively older subjective ages (Est.-0.10, SE=0.02, p<.001). For episodic memory, higher levels of perceived constraints were associated with worse performance (Est.=-0.07, SE=0.03, p<.001), while reporting a more youthful subjective age was associated with better performance (Est.-0.10, SE=0.02, p<.001). Mastery was not associated with either cognitive domain (ps>.05). Results suggest that perceiving constraints in life may confer greatest risk to cognitive performance among adults who feel older than their actual age, whereas perceiving a more youthful subjective age may be more facilitative.