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Nevin Manimala Statistics

Brownian systems perturbed by mild shear: Comparing response relations

J Phys Condens Matter. 2021 Jun 17. doi: 10.1088/1361-648X/ac0c3c. Online ahead of print.

ABSTRACT

We present a comprehensive study of the linear response of interacting underdamped Brownian particles to simple shear flow. We collect six different routes for computing the response, two of which are based on the symmetry of the considered system and observable with respect to the shear axes. We include the extension of the Green-Kubo relation to underdamped cases, which shows two unexpected additional terms. These six computational methods are applied to investigate the relaxation of the response towards the steady state for different observables, where interesting effects due to interactions and a finite particle mass are observed. Moreover, we compare the different response relations in terms of their statistical efficiency, identifying their relative demand on experimental measurement time or computational resources in computer simulations. Finally, several measures of breakdown of linear response theory for larger shear rates are discussed.

PMID:34139676 | DOI:10.1088/1361-648X/ac0c3c

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Nevin Manimala Statistics

Interacting drivers and their tradeoffs for predicting denitrification potential across a strong urban to rural gradient within heterogeneous landscapes

J Environ Manage. 2021 Jun 14;294:113021. doi: 10.1016/j.jenvman.2021.113021. Online ahead of print.

ABSTRACT

Denitrification is a significant regulator of nitrogen pollution in diverse landscapes but is difficult to quantify. We examined relationships between denitrification potential and soil and landscape properties to develop a model that predicts denitrification potential at a landscape level. Denitrification potential, ancillary soil variables, and physical landscape attributes were measured at study sites within urban, suburban, and forested environments in the Gwynns Falls watershed in Baltimore, Maryland in a series of studies between 1998 and 2014. Data from these studies were used to develop a statistical model for denitrification potential using a subset of the samples (N = 188). The remaining measurements (N = 150) were used to validate the model. Soil moisture, soil respiration, and total soil nitrogen were the best predictors of denitrification potential (R2adj = 0.35), and the model was validated by regressing observed vs. predicted values. Our results suggest that soil denitrification potential can be modeled successfully using these three parameters, and that this model performs well across a variety of natural and developed land uses. This model provides a framework for predicting nitrogen dynamics in varying land use contexts. We also outline approaches to develop appropriate landscape-scale proxies for the key model inputs, including soil moisture, respiration, and soil nitrogen.

PMID:34139648 | DOI:10.1016/j.jenvman.2021.113021

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Nevin Manimala Statistics

Gradual development of non-adjacent dependency learning during early childhood

Dev Cogn Neurosci. 2021 Jun 11;50:100975. doi: 10.1016/j.dcn.2021.100975. Online ahead of print.

ABSTRACT

In order to become proficient native speakers, children have to learn the morpho-syntactic relations between distant elements in a sentence, so-called non-adjacent dependencies (NADs). Previous research suggests that NAD learning in children comprises different developmental stages, where until 2 years of age children are able to learn NADs associatively under passive listening conditions, while starting around the age of 3-4 years children fail to learn NADs during passive listening. To test whether the transition between these developmental stages occurs gradually, we tested children’s NAD learning in a foreign language using event-related potentials (ERPs). We found ERP evidence of NAD learning across the ages of 1, 2 and 3 years. The amplitude of the ERP effect indexing NAD learning, however, decreased with age. These findings might indicate a gradual transition in children’s ability to learn NADs associatively. Cognitively, this transition might be driven by children’s increasing knowledge of their native language, hindering NAD learning in novel contexts. Neuroanatomically, maturation of the prefrontal cortex might play a crucial role, promoting top-down learning, affecting bottom-up, associative learning. In sum, our study suggests that NAD learning under passive listening conditions undergoes a gradual transition between different developmental stages during early childhood.

PMID:34139635 | DOI:10.1016/j.dcn.2021.100975

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Nevin Manimala Statistics

Effects of long-term air pollution exposure on ankle-brachial index and cardio-ankle vascular index: A longitudinal cohort study using data from the Electricity Generating Authority of Thailand study

Int J Hyg Environ Health. 2021 Jun 14;236:113790. doi: 10.1016/j.ijheh.2021.113790. Online ahead of print.

ABSTRACT

BACKGROUND: Ankle-brachial index (ABI) and cardio-ankle vascular index (CAVI) are surrogate measures of atherosclerosis based on the functional performance of vessels, and are highly related to cardiovascular events. However, only a few longitudinal studies have been conducted on their associations with long-term air pollution exposure.

OBJECTIVE: This study aimed to examine whether long-term air pollution exposure is associated with ABI and CAVI in workers of the Electricity Generating Authority of Thailand (EGAT) in the Bangkok Metropolitan Region (BMR).

METHODS: This longitudinal study included 1261 participants (age range, 57-76 years as of 2007) of the EGAT study (2007-2017). ABI and CAVI were measured in 2007, 2012, and 2017. Annual mean concentrations of particulate matter ≤10 μm in diameter (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2), ozone (O3), and carbon monoxide (CO) were estimated by ordinary kriging using data from 22 background and 7 traffic monitoring stations in BMR between 2002 and 2017. Linear mixed-effects models were used to assess associations between air pollution (expressed as 1-year, 3-year, and 5-year average concentration) and ABI and CAVI (expressed as percent changes per interquartile range (IQR) increase in PM10, O3, NO2, SO2, and CO). We also applied the mixed-effect ordinal logistic models to calculate odds ratios (ORs) of having high or moderate CAVI per an IQR increase in air pollution.

RESULTS: After controlling for potential confounders, 1-year average CO was negatively associated with ABI, but not significantly (-0.48%, 95% CI: -1.03, 0.07). Three-year average NO2 was positively associated with CAVI (6.67%, 95% CI: 0.21, 13.1). In contrast, 1-year average PM10 was inversely associated with CAVI although the association was not significant. Although not significantly, 1-year average NO2 and CO were positively associated with prevalence of high or moderate CAVI.

CONCLUSIONS: Although not statistically significant, long-term NO2 and CO exposure was associated with ABI and CAVI in the participants of the EGAT study.

PMID:34139634 | DOI:10.1016/j.ijheh.2021.113790

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Nevin Manimala Statistics

On fossil recovery potential in the Australopithecus anamensis-Australopithecus afarensis lineage: A reply to

J Hum Evol. 2021 Jun 14;157:103025. doi: 10.1016/j.jhevol.2021.103025. Online ahead of print.

NO ABSTRACT

PMID:34139622 | DOI:10.1016/j.jhevol.2021.103025

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Nevin Manimala Statistics

Nematode parasitism affects lying time and overall activity patterns in lambs following pasture exposure around weaning

Vet Parasitol. 2021 Jun 11;296:109500. doi: 10.1016/j.vetpar.2021.109500. Online ahead of print.

ABSTRACT

We investigated the effects of gastrointestinal nematode (GIN) challenge on activity in first season grazing lambs naturally exposed to two different levels of multispecies GIN infections. Ewes and their twin-born lambs were turned-out to graze in two permanent pasture enclosures naturally contaminated with GIN the previous year, thereby exposing them to overwintering strongyle larvae. Animals in the low parasite exposure group (LP) were dewormed monthly with 0.2 mg ivermectin (Ivomec® vet, oral suspension) per kg body weight, whereas those in high parasite exposure group (HP) were left untreated. At weaning, lambs were allocated to one out of four groups based on weight and sex (HPE, n = 15; HPR, n = 15; LPE, n = 14; LPR, n = 14), in four nearby non-contaminated ley enclosures of similar size. Activity patterns were monitored from day -7, i.e. 7 days pre-weaning, until day 49, i.e. 49 days post-weaning, by fitting all lambs with IceQube sensors (IceRobotics). Body weight was monitored weekly from day -21, whereas faecal samples were investigated at days -21, 7, 35 and 49 for nematode faecal egg counts (EPG) using McMaster-technology and a validated Droplet Digital PCR protocol to determine nematode composition. All statistical analyses were performed in R studio, using mixed models with repeated measures. In the data analyses, weekly recordings was treated as a period, generating a total of eight periods. Average daily lying time had a significant interaction between parasite exposure and period (P = 0.0013), with animals in HP having a 101 ± 31 min shorter daily lying time compared to LP. Motion Index (MI; absolute value of the 3-D acceleration) had a significant interaction between parasite exposure and period (P = 0.0001) with lambs in group HP having a lower average daily MI compared with LP. Both body weight gain and EPG levels were significantly different (P<0.0001) between HP and LP groups during the course of the study. The molecular investigation showed that animals were predominantly infected with Teladorsagia spp., combined with low proportions of Haemonchus spp. In conclusion, this study shows that lying time and Motion Index of lambs around weaning was affected by moderate nematode infections. This indicates that there is a potential use of automated behaviour recordings as a diagnostic tool for detection of nematode parasites in lambs even at moderate infection levels.

PMID:34139614 | DOI:10.1016/j.vetpar.2021.109500

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Nevin Manimala Statistics

The economic crisis impact on the body mass index of children living in distinct urban environments

Public Health. 2021 Jun 14;196:29-34. doi: 10.1016/j.puhe.2021.04.030. Online ahead of print.

ABSTRACT

OBJECTIVES: Little is known about the impact of the 2008 global economic recession on childhood obesity in Portugal. Thus, this study’s goals were to compare weight status of children during and after the economic crisis according to their neighbourhood environment features and to assess changes in specific dietary habits during the economic crisis.

STUDY DESIGN: Cross-sectional study.

METHODS: Data including weight, height, residence address to allow its geocoding and dietary habits changes during the crisis from children living in Lisbon municipality were collected in 2009 (N = 929) and in 2016 (N = 1751). A multidimensional environment index, with data of both built and socioeconomic nature collected at the statistical section level (areas comprised 300 dwellers) in the 2011 census, was used to characterize neighbourhoods.

RESULTS: Overall, the proportion of children who are overweight or obese living in the socioeconomically vulnerable areas decreased in 2016. Families living in the latter areas stopped buying some food items, started to buy cheaper food items, cooked more meals at home and ate less in restaurants. In 2016, the risk for overweight and obesity increased in children who lived in the least advantageous areas. Living in areas with high socioeconomic status or most advantageous areas no longer represented a decreased risk of being overweight or obese in children in 2016 as it did in 2009.

CONCLUSIONS: This study suggests that the economic crisis enhanced the social inequalities regarding childhood obesity. These results aid the development of evidence-based strategies to lessen the social inequities in health outcomes created by the crisis.

PMID:34139606 | DOI:10.1016/j.puhe.2021.04.030

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Nevin Manimala Statistics

Self-determination in Male Children with Intellectual Disabilities: Perceptions of Parents from Saudi Arabia

Res Dev Disabil. 2021 Jun 14;115:104011. doi: 10.1016/j.ridd.2021.104011. Online ahead of print.

ABSTRACT

BACKGROUND: Self-determination is essential for improving the quality of life of individuals with disabilities. Prior research has indicated that parents’ values and practices are important in supporting the development of self-determination in their children.

AIM: The purpose of the study was to examine Saudi Arabian parents’ values and perceptions regarding the importance, performance, and provision of self-determination opportunities to their high school male children with and without intellectual disability.

METHODS: The participants were 133 parents of high school children (76 parents of a child without disabilities and 57 parents of a child with intellectual disabilities, accounting for 57.1% and 42.8%, respectively). Data were collected using a self-report questionnaire. Descriptive statistics and independent samples t-tests were used to understand parents’ perceptions of and behaviors related to self-determination.

RESULTS: The results revealed no significant difference in the ratings of the importance of self-determination between the two groups of parents. Parents of children with intellectual disabilities rated their child’s self-determination performance lower and provided fewer opportunities to improve their children’s self-determination.

CONCLUSION: The results suggested that self-determination skills were valued in Saudi Arabia, highlighting that disability may affect the performance and opportunities to practice self-determination.

PMID:34139600 | DOI:10.1016/j.ridd.2021.104011

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Nevin Manimala Statistics

Potential health risks due to in-car aerosol exposure across ten global cities

Environ Int. 2021 Jun 14;155:106688. doi: 10.1016/j.envint.2021.106688. Online ahead of print.

ABSTRACT

Car microenvironments significantly contribute to the daily pollution exposure of commuters, yet health and socioeconomic studies focused on in-car exposure are rare. This study aims to assess the relationship between air pollution levels and socioeconomic indicators (fuel prices, city-specific GDP, road density, the value of statistical life (VSL), health burden and economic losses resulting from exposure to fine particulate matter ≤2.5 µm; PM2.5) during car journeys in ten cities: Dhaka (Bangladesh); Chennai (India); Guangzhou (China); Medellín (Colombia); São Paulo (Brazil); Cairo (Egypt); Sulaymaniyah (Iraq); Addis Ababa (Ethiopia); Blantyre (Malawi); and Dar-es-Salaam (Tanzania). Data collected by portable laser particle counters were used to develop a proxy of car-user exposure profiles. Hotspots on all city routes displayed higher PM2.5 concentrations and disproportionately high inhaled doses. For instance, the time spent at the hotspots in Guangzhou and Addis Ababa was 26% and 28% of total trip time, but corresponded to 54% and 56%, respectively, of the total PM2.5 inhaled dose. With the exception of Guangzhou, all the cities showed a decrease in per cent length of hotspots with an increase in GDP and VSL. Exposure levels were independent of fuel prices in most cities. The largest health burden related to in-car PM2.5 exposure was estimated for Dar-es-Salam (81.6 ± 39.3 μg m-3), Blantyre (82.9 ± 44.0) and Dhaka (62.3 ± 32.0) with deaths per 100,000 of the car commuting population per year of 2.46 (2.28-2.63), 1.11 (0.97-1.26) and 1.10 (1.05-1.15), respectively. However, the modest health burden of 0.07 (0.06-0.08), 0.10 (0.09-0.12) and 0.02 (0.02-0.03) deaths per 100,000 of the car commuting population per year were estimated for Medellin (23 ± 13.7 μg m-3), São Paulo (25.6 ± 11.7) and Sulaymaniyah (22.4 ± 15.0), respectively. Lower GDP was found to be associated with higher economic losses due to health burdens caused by air pollution in most cities, indicating a socioeconomic discrepancy. This assessment of health and socioeconomic parameters associated with in-car PM2.5 exposure highlights the importance of implementing plausible solutions to make a positive impact on peoples’ lives in these cities.

PMID:34139587 | DOI:10.1016/j.envint.2021.106688

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Nevin Manimala Statistics

Systematic review: Exploration of the impact of psychosocial factors on quality of life in adults living with coeliac disease

J Psychosom Res. 2021 May 28;147:110537. doi: 10.1016/j.jpsychores.2021.110537. Online ahead of print.

ABSTRACT

BACKGROUND: Individuals living with coeliac disease generally experience a remission of symptoms after adopting the gluten-free diet but often report substantial treatment burden and ongoing quality of life issues. Psychosocial factors have been suggested to play a significant role in post-diagnosis quality of life but have yet to be systematically reviewed.

AIM: To review the evidence for psychosocial factors associated with quality of life in adult coeliac disease cohorts.

METHODS: Studies were identified via systematic searches of eight databases (MEDLINE, Embase, Emcare, PsycINFO, Ovid Nursing, CINAHL, Informit Health Collection, Cochrane Library) in May 2019.

RESULTS: Fourteen studies were included involving 3372 participants (80.2% female, mean age = 46.4 years). Symptoms of depression and anxiety were the most examined psychosocial factors across all studies. Quality of life was differentially associated with psychological distress, illness perceptions, coping, and attitudes/behaviours regarding food and the gluten-free diet.

CONCLUSION: Several psychosocial factors are associated with quality of life in adults living with coeliac disease. Current evidence suggests these factors are interrelated and may influence quality of life directly, via reduced psychological well-being, and indirectly, via reduced adherence to the gluten-free diet. Future research is needed to examine these processes concurrently, with the aim of elucidating the psychosocial mechanisms underlying post-diagnosis well-being and identifying potential targets for psychosocial intervention.

PMID:34139581 | DOI:10.1016/j.jpsychores.2021.110537