Weighted single step GWAS reveals genomic regions associated with economic traits in Murrah buffaloes.

The objective of the present study was to identify genomic regions influencing economic traits in Murrah buffaloes using weighted single step Genome Wide Association Analysis (WssGWAS). Data on 2000 animals, out of which 120 were genotyped using a double digest Restriction site Associated DNA (ddRAD) sequencing approach. The phenotypic data were collected from NDRI, India, on growth traits, viz., body weight at 6M (month), 12M, 18M and 24M, production traits like 305D (day) milk yield, lactation length (LL) and dry period (DP) and reproduction traits like age at first calving (AFC), calving interval (CI) and first service period (FSP). The biallelic genotypic data consisted of 49353 markers post-quality check. The heritability estimates were moderate to high, low to moderate, low for growth, production, reproduction traits, respectively. Important genomic regions explaining more than 0.5% of the total additive genetic variance explained by 30 adjacent SNPs were selected for further analysis of candidate genes. In this study, 105 genomic regions were associated with growth, 35 genomic regions with production and 42 window regions with reproduction traits. Different candidate genes were identified in these genomic regions, of which important are OSBPL8, NAP1L1 for growth, CNTNAP2 for production and ILDR2, TADA1 and POGK for reproduction traits.

Understanding the health decline of Americans in boomers to millennials.

Morbidity and mortality are on the rise among Americans from Boomers to Millennials. We investigate early-life diseases and the socioeconomic, psychosocial, and bio-behavioral factors behind this worsening health trend. Using data from the Panel Study of Income Dynamics Family and Individual Files 1968-2013, we find that the chronic disease index and poor subjective health have continuously increased for Baby Boomers and later cohorts. Early-life diseases, obesity, and shortening job tenure account for about half the health decline across cohorts. Weakening union protection, decreasing marriage, and declining religion only make minor contributions. All other factors, including early life nutrition and family background, adulthood socioeconomic status, physical activity, and smoking behaviors, make negative or non-significant contributions. These findings highlight that even though recent cohorts have better childhood nutrition, family socioeconomic environment,and higher levels of education and income, these advantages have been offset by elevated early-life disease exposure, obesity, and a precarious labor market. We discuss the findings in the context of Case and Deaton's "cumulative deprivation" thesis.

Genetic improvement of economic traits in Murrah buffalo using significant SNPs from genome-wide association study.

GWAS helps to identify QTL and candidate genes of specific traits. Buffalo breeding has primarily focused on milk production, but its negative correlation with reproduction traits resulted in unfavorable decline of reproductive performance among buffaloes. A genome wide scan was performed on a total of 120 Murrah buffaloes genotyped by ddRAD sequencing for 13 traits related to female fertility, production, and growth. The identified 25 significant single nucleotide polymorphisms (SNPs) (P <1×106) are associated with age at first calving (AFC), age at first service (AFS), period from calving to 1st Artifical Insemination (AI), service period (SP) and 6 month body weight (6M). Fifteen genetic variants overlapped with different QTL regions of reported studies. Among the associated loci, outstanding candidate genes for fertility, including AQP1, TRNAE-CUC, NRIP1, CPNE4, and VOPP1, have effect in different fertility traits. AQP1 gene is expressed in ovulatory phase and various stages of pregnancy. TRNAE-CUC gene is associated with AFC and number . of calvings after 4 years of age. Glycogen content-associated gene CPNE4 regulates muscle glycogen and is upregulated during early pregnancy. NRIP1 generegulates ovulation, corpus luteum at pregnancy, and mammary gland development. The objective is to identify potential genomic regions and genetic variants associated with economic traits and to select the most significant SNP which have positive effect on all the traits.

Genomic clues of association between clinical mastitis and SNPs identified by ddRAD sequencing in Murrah buffaloes.

The total milk production of India is 209.96 MT out of which 45% is contributed by the indigenous buffalo and due to their high producing virtue, the prevalence of mastitis is 5-20%. Despite the increasing level of technological advancement, mastitis is still an issue of concern for dairy industry in India as well as across the world. Therefore, the present study aimed to identify the SNPs and associate them with the incidence of clinical mastitis in Murrah buffalo using the ddRAD sequencing approach taking mastitis incidence data of 96 Murrah buffaloes. A total of 246 million quality controlled reads were obtained with an average alignment rate of 99.01% and at a read depth of 10, quality controlled SNPs obtained were 18,056. The logistic regression model was used and a total of seven SNPs were found significantly associated (p < 0.001) with mastitis incidence and seven genes were identified viz., NCBP1, FOXN3, TPK1, XYLT2, CPXM2, HERC1, and OPCML. The majority of them were having tumor suppressing action, related to immunogenetics or glycolytic and energy production. Conclusively, the SNPs identified in this study may be useful for future studies on mastitis incidence in Murrah buffalo and the SNP associations can be further validated.

Estimation of genetic parameters of growth traits for direct and maternal effects in Murrah buffalo.

An understanding of genetic principles and environmental factors affecting the growth traits is essential to implement optimal breeding and selection programs. Early growth is an indicator of future success in production and reproduction status of dairy animals. In this study, a total of 18,989 records of body weight were used to estimate genetic parameters of body weight at birth (BW), 3 months (3BW), 6 months (6BW), 9 months (9BW),12 months (12BW), 18 months (18BW), 24 months (24 BW), 30 months (3BW), and 36 months (36BW) in Murrah buffalo at ICAR-NDRI Karnal, Haryana, for the period 1974-2019. The genetic parameters were estimated using the average information restricted maximum likelihood (AIREML) procedure by excluding or including maternal effects. Six analytical models were fitted in order to optimize the model for each trait. The most appropriate univariate model was selected based on the log likelihood ratio test (LRT). Influencing factors like calf sex, period of birth, season of birth, and dam's parity were investigated. The results showed that the maternal genetic effects, in addition to direct additive effects, were important for unbiased and accurate genetic parameter estimates of growth traits in Murrah buffaloes. Total heritability estimates h2T1 for BW, 3BW, 6BW, 9BW, 12BW, 18BW, 24BW, 30BW, and 36BW were 0.25, 0.04, 0.14, 0.16, 0.10, 0.15, 0.21, 0.24, and 0.23, respectively. Maternal effect was significant for birth weight and accounted for 13% variation through maternal genetic and 5% variability through maternal permanent environmental effect. Maternal genetic effect was also important for other traits. However, it interfered with the estimates of variance ratios in live weight traits owing to large and negative covariance between direct and maternal genetic effects. Direct genetic correlations between body weight traits were positive and high ranging from 0.10 to 0.94. Results revealed that the Murrah herd has a sizable genetic variability for growth traits and hence, there is sufficient scope for selection for achieving better growth rate if selection in this direction is applied. Owing to higher positive genetic correlation of 6BW with later ages, the scope of indirect selection for optimum growth in later ages can be aimed at by selecting animals for their higher 6-month live weight.

Socio-culturally adapted educational videos increase maternal and newborn health knowledge in pregnant women and female community health volunteers in Nepal's Khotang district.

OBJECTIVES: While Nepal has made significant improvements in maternal and newborn health overall, the lack of maternal and newborn health-related knowledge in the more rural parts of the country has led to significant disparities in terms of both maternal and newborn health service utilization and maternal and newborn health outcomes. This study aimed to assess whether viewing culturally adapted maternal and newborn health educational films had a positive impact on (1) the maternal and newborn health knowledge levels among pregnant women and (2) the postpartum hemorrhage-related knowledge levels among Female Community Health Volunteers in rural Nepal. METHODS: Four locations were selected for their remoteness and comparatively high number of pregnancies. A convenience sample of 101 pregnant women and 39 Female Community Health Volunteers were enrolled in the study. A pre- and post-test design was employed to assess this intervention. Paired t-tests were used to analyze the change in number of correct responses by knowledge domain for multi-film participants, producing a numeric "mean knowledge score," and McNemar's tests were used to calculate the change and significance among select questions grouped into distinct themes, domains, and points of "maternal and newborn health-related knowledge" based on the priorities outlined in Nepal's maternal and newborn health 2030 goals. RESULTS: There was a significant improvement in knowledge scores on maternal and newborn health issues after watching the educational films for both types of participants. The mean knowledge score for pregnant women improved from 10 to 15 (P < 0.001) for the Understanding Antenatal Care (ANC) film, 3 to 10 (P < 0.001) for the Warning Sign in Pregnancy film, and 6 to 14 (P < 0.001) for the Newborn Care film. For the Female Community Health Volunteers, knowledge also significantly improved (P < 0.05) in all except one category after watching the postpartum hemorrhage film. The percent that correctly answered when to administer misoprostol (80%-95%) was the only variable in which knowledge improvement was not significant (P < 0.057). CONCLUSION: Using culturally adapted educational films is an effective intervention to improve short-term maternal and newborn health-related knowledge among rural populations with low educational levels. The authors recommend additional larger-scale trials of this type of intervention in Nepal and other low- and middle-income countries to determine the impact on long-term maternal and newborn health knowledge and behaviors among rural populations.

Rising childhood income inequality and declining Americans' health.

Morbidity and mortality are on the rise among Baby Boomers and younger cohorts. This study investigates whether this unfavorable health trend across birth cohorts 1925-1999 is related to rising income inequality Americans face during childhood. We use two nationally representative datasets: National Health and Nutrition Examination Surveys (NHANES) 1988-2018 and Panel Studies of Income Dynamics (PSID) 1968-2013, and two health outcomes: biomarkers of physiological dysregulation, and a chronic disease index. Childhood income inequality is measured by the average of the Gini index at the national level each birth cohort is exposed to between birth and age 18, where the Gini index from 1925 to 2016 is computed based on Internal Revenue Service income data. By merging childhood income inequality to individual level data from NHANES or PSID based on birth cohort, we find childhood income inequality is positively associated with the risk of physiological dysregulation in adulthood for all gender and racial groups in the NHANES data. It is also significantly related to the risk of chronic disease in the PSID data. This association is robust to controls for individual level childhood health and family background, adulthood socioeconomic and marital status, and contemporary macro socioeconomic factors. More importantly, childhood income inequality exposure explains a substantial amount of variation in these two health outcomes across cohorts, a pattern not observed for other early life exposures that display negative temporal trends similar to those for childhood income inequality. This study provides important evidence that income inequality experienced during childhood may have a long-lasting negative consequence for adult health, which partially explains the adverse health trends experienced by Baby Boomers and younger cohorts in the United States.

The Cumulative Impact of Chronic Stressors on Risks of Myocardial Infarction in US Older Adults.

OBJECTIVE: This study aimed to investigate the association between cumulative exposure to chronic stressors and the incidence of myocardial infarction (MI) in US older adults. METHODS: Nationally representative prospective cohort data of adults 45 years and older (n = 15,109) were used to investigate the association between the cumulative number of chronic stressors and the incidence of MI in US older adults. Proportional hazards models adjusted for confounding risk factors and differences by sex, race/ethnicity, and history of MI were assessed. RESULTS: The median age of participants was 65 years, 714 (4.7%) had a prior MI, and 557 (3.7%) had an MI during follow-up. Approximately 84% of participants reported at least one chronic stressor at baseline, and more than half reported two or more stressors. Multivariable models showed that risks of MI increased incrementally from one chronic stressor (hazard ratio [HR] = 1.28, 95% confidence interval [CI] = 1.20-1.37) to four or more chronic stressors (HR = 2.71, 95% CI = 2.08-3.53) compared with those who reported no stressors. These risks were only partly reduced after adjustments for multiple demographic, socioeconomic, psychosocial, behavioral, and clinical risk factors. In adults who had a prior MI (p value for interaction = .038), we found that risks of a recurrent event increased substantially from one chronic stressor (HR = 1.30, 95% CI = 1.09-1.54) to four or more chronic stressors (HR = 2.85, 95% CI = 1.43-5.69). CONCLUSIONS: Chronic life stressors are significant independent risk factors for cardiovascular events in US older adults. The risks associated with multiple chronic stressors were especially high in adults with a previous MI.

High-Efficiency Air Cleaning Reduces Indoor Traffic-Related Air Pollution and Alters Indoor Air Chemistry in a Near-Roadway School.

Schools in proximity to roadways expose students to traffic-related air pollution (TRAP). We investigate impacts of air-cleaning on indoor TRAP levels and indoor chemistry in a renovated school adjacent an interstate highway. We monitor air pollutants pre- and post-renovation and quantify efficiency of particle (MERV8 and 16 filters) and gas (functionalized activated carbon) air-cleaning. Time-resolved measurements show air-cleaning systems are effective, with in situ particle removal efficiency >94% across 10 nm to 10 µm. Activated carbon removed BTEX and NO2 with variability in removal efficiency. Over eight months of monitoring, NO2 removal efficiency was 96% initially and decreased to 61%; and BTEX removal efficiency was >80% or increased to >80%. Air-cleaning reduced indoor TRAP to below or near urban background. Air-cleaning systems suppressed indoor chemistry by reducing indoor levels of oxidants (NO2, O3) and reactive organics of indoor origin. When the air cleaning system was inactive, our data show that indoor SOA formation within the school was elevated. Loss rates of NO2 and O3 through the air-cleaning system were ∼1.5-2.4 h-1 and ∼2.3 h-1, respectively. Air-cleaning was 83% and 69% efficient, respectively, in removing monoterpenes and isoprene. By suppressing precursors, scaling calculations show air-cleaning prevented ∼3.4 mg/h of indoor SOA formation due to indoor ozone-monoterpene chemistry. For comparison, we estimate that filtration removed ∼130 mg/h of PM0.01-0.3.

Does Medical Expansion Improve Population Health?

Medical expansion has become a prominent dynamic in today's societies as the biomedical model becomes increasingly dominant in the explanation of health, illness, and other human problems and behavior. Medical expansion is multidimensional and represented by expansions in three major components of the healthcare system: increasing medical investment, medical professionalization/specialization, and the relative size of the pharmaceutical industry. Using Organisation for Economic Co-operation and Development health data and World Development Indicators 1981 to 2007, we find medical investment and medical professionalization/specialization significantly improve all three measures of life expectancy and decrease mortality rate even after controlling for endogeneity problems. In contrast, an expanded pharmaceutical industry is negatively associated with female life expectancy at age 65 and positively associated with the all-cause mortality rate. It further compromises the beneficial effect of medical professionalization/specialization on population health. In general, medical professionalization/specialization and gross domestic product per capita have similar and stronger effects than medical investment.

Relating Sensory, Cognitive, and Neural Factors to Older Persons' Perceptions about Happiness: An Exploratory Study.

Despite increased rates of disease, disability, and social losses with aging, seniors consistently report higher levels of subjective well-being (SWB), a construct closely related to happiness, than younger adults. In this exploratory study, we utilized an available dataset to investigate how aspects of health commonly deteriorating with age, including sensory (i.e., vision and hearing) and cognitive status, relate to variability in self-described contributors to happiness. Community-dwelling seniors (n = 114) responded to a single-item prompt: "name things that make people happy." 1731 responses were categorized into 13 domains of SWB via structured content analysis. Sensory health and cognition were assessed by Snellen visual acuity, pure-tone audiometry, and in-person administration of the Brief Test of Adult Cognition by Telephone (BTACT) battery. A subset of eligible participants (n = 57) underwent functional magnetic resonance imaging (fMRI) to assess resting state functional connectivity (FC) within a previously described dopaminergic network associated with reward processing. SWB response patterns were relatively stable across gender, sensory status, and cognitive performance with few exceptions. For example, hearing-impaired participants listed fewer determinants of SWB (13.59 vs. 17.16; p < 0.001) and were less likely to name things in the "special events" category. Participants with a higher proportion of responses in the "accomplishments" domain (e.g., winning, getting good grades) demonstrated increased FC between the ventral tegmental area and nucleus accumbens, regions implicated in reward and motivated behavior. While the framework for determinants of happiness among seniors was largely stable across the factors assessed here, our findings suggest that subtle changes in this construct may be linked to sensory loss. The possibility that perceptions about determinants of happiness might relate to differences in intrinsic connectivity within reward-related brain networks also warrants further investigation.

Assessing the Potential of Land Use Modification to Mitigate Ambient NO2 and Its Consequences for Respiratory Health.

Understanding how local land use and land cover (LULC) shapes intra-urban concentrations of atmospheric pollutants-and thus human health-is a key component in designing healthier cities. Here, NO2 is modeled based on spatially dense summer and winter NO2 observations in Portland-Hillsboro-Vancouver (USA), and the spatial variation of NO2 with LULC investigated using random forest, an ensemble data learning technique. The NO2 random forest model, together with BenMAP, is further used to develop a better understanding of the relationship among LULC, ambient NO2 and respiratory health. The impact of land use modifications on ambient NO2, and consequently on respiratory health, is also investigated using a sensitivity analysis. We find that NO2 associated with roadways and tree-canopied areas may be affecting annual incidence rates of asthma exacerbation in 4-12 year olds by +3000 per 100,000 and -1400 per 100,000, respectively. Our model shows that increasing local tree canopy by 5% may reduce local incidences rates of asthma exacerbation by 6%, indicating that targeted local tree-planting efforts may have a substantial impact on reducing city-wide incidence of respiratory distress. Our findings demonstrate the utility of random forest modeling in evaluating LULC modifications for enhanced respiratory health.

Incorporating biomarkers into the study of socio-economic status and health among older adults in China.

The social gradient in health - that individuals with lower SES have worse health than those with higher SES- is welldocumented using self-reports of health in more developed countries. Less is known about the relationship between SES and health biomarkers among older adults residing in less developed countries. We use data from the ChineseLongitudinal Healthy Longevity Survey (CLHLS) longevity areas sub-sample to examine the social gradient in healthamong rural young-old and oldest-old adults (N=2,121). Our health indicators include individual biomarkers, metabolic syndrome, and self-reports of health. We found a largely positive relationship between SES and health. SES was more consistently associated with individual biomarkers among the oldest-old than the young-old, providing evidence for cumulative disadvantage. We discuss the implications of our findings for older adults who have lived through different social, economic, and health regimes.

Integrating High-Resolution Datasets to Target Mitigation Efforts for Improving Air Quality and Public Health in Urban Neighborhoods.

Reducing exposure to degraded air quality is essential for building healthy cities. Although air quality and population vary at fine spatial scales, current regulatory and public health frameworks assess human exposures using county- or city-scales. We build on a spatial analysis technique, dasymetric mapping, for allocating urban populations that, together with emerging fine-scale measurements of air pollution, addresses three objectives: (1) evaluate the role of spatial scale in estimating exposure; (2) identify urban communities that are disproportionately burdened by poor air quality; and (3) estimate reduction in mobile sources of pollutants due to local tree-planting efforts using nitrogen dioxide. Our results show a maximum value of 197% difference between cadastrally-informed dasymetric system (CIDS) and standard estimations of population exposure to degraded air quality for small spatial extent analyses, and a lack of substantial difference for large spatial extent analyses. These results provide the foundation for improving policies for managing air quality, and targeting mitigation efforts to address challenges of environmental justice.

Older parents enjoy better filial piety and care from daughters than sons in China.

This study analyzes the unique datasets of the Chinese Longitudinal Healthy Longevity Survey using logistic regression and controlling for various covariates. Our analyses clearly demonstrate that disabled older parents are more satisfied with care provided by daughters than sons and that older parents enjoy greater filial piety from and better relationships with daughters than sons. The daughter-advantages of enjoying greater filial piety from and better relationships with children are stronger among the oldest-old aged 80+ than the young-old aged 65-79, and surprisingly more profound in rural areas than urban areas, while son-preference is much more prevalent among rural residents. We also discuss why China's rigorous fertility policy until October-2015 and much less-developed pension system in rural areas substantially contribute to sustaining traditional son-preference and a high sex ratio at birth (SRB) when fertility is low. We recommend China take integrative public health policy actions of informing the public that having daughter(s) is beneficial for old age care, developing the rural pension system and implementing the universal two-child policy as soon as possible. We believe that these policy actions would help to reduce son-preference, bring down the high SRB, and enable more future elderly parents to enjoy better care from their children and healthier lives.

Socioeconomic determinants of childhood overweight and obesity in China: the long arm of institutional power.

Previous studies have widely reported that the association between socioeconomic status (SES) and childhood overweight and obesity in China is significant and positive, which lends little support to the fundamental-cause perspective. Using multiple waves (1997, 2000, 2004 and 2006) of the China Health and Nutrition Survey (CHNS) (N = 2,556, 2,063, 1,431 and 1,242, respectively) and continuous BMI cut-points obtained from a polynomial method, (mixed-effect) logistic regression analyses show that parental state-sector employment, an important, yet overlooked, indicator of political power during the market transformation has changed from a risk factor for childhood overweight/obesity in 1997 to a protective factor for childhood overweight/obesity in 2006. Results from quantile regression analyses generate the same conclusions and demonstrate that the protective effect of parental state sector employment at high percentiles of BMI is robust under different estimation strategies. By bridging the fundamental causes perspective and theories of market transformation, this research not only documents the effect of political power on childhood overweight/obesity but also calls for the use of multifaceted, culturally-relevant stratification measures in testing the fundamental cause perspective across time and space.

Association between divorce and risks for acute myocardial infarction.

BACKGROUND: Divorce is a major life stressor that can have economic, emotional, and physical health consequences. However, the cumulative association between divorce and risks for acute myocardial infarction (AMI) is unknown. This study investigated the association between lifetime exposure to divorce and the incidence of AMI in US adults. METHODS AND RESULTS: We used nationally representative data from a prospective cohort of ever-married adults aged 45 to 80 years (n=15,827) who were followed biennially from 1992 to 2010. Approximately 14% of men and 19% of women were divorced at baseline and more than one third of the cohort had ≥1 divorce in their lifetime. In 200,524 person-years of follow-up, 8% (n=1211) of the cohort had an AMI and age-specific rates of AMI were consistently higher in those who were divorced compared with those who were continuously married (P<0.05). Results from competing-risk hazard models showed that AMI risks were significantly higher in women who had 1 divorce (hazard ratio, 1.24; 95% confidence interval, 1.01-1.55), ≥2 divorces (hazard ratio, 1.77; 95% confidence interval, 1.30-2.41), and among the remarried (hazard ratio, 1.35; 95% confidence interval, 1.07-1.70) compared with continuously married women after adjusting for multiple risk factors. Multivariable-adjusted risks were elevated only in men with a history of ≥2 divorces (hazard ratio, 1.30; 95% confidence interval, 1.02-1.66) compared with continuously married men. Men who remarried had no significant risk for AMI. Interaction terms for sex were not statistically significant. CONCLUSIONS: Divorce is a significant risk factor for AMI. The risks associated with multiple divorces are especially high in women and are not reduced with remarriage.

Sex, Socioeconomic and Regional Disparities in Age Trajectories of Childhood BMI, Underweight and Overweight in China.

Using a longitudinal dataset from the China Health and Nutrition Survey (CHNS), growth curve models were employed to examine age trajectories of BMI for 1,694 subjects who were aged 2-11 in 1993 and followed in four waves (1997, 2000, 2004 and 2006). Based on age- and sex-specific BMI cut-points recommended for international use, the prevalence rates of overweight and underweight in the transition from childhood to adulthood (age 6-18) were also predicted. Sex, family income, rural-urban residency and geographical location were found to be significantly associated with the onsets, slopes, and acceleration of age trajectories in BMI, overweight, and underweight (P<0.01). Children who had lower prevalence of underweight in the transition from childhood to adulthood exhibited higher prevalence of overweight than their counterparts did. Moreover, the age interval during which children were more vulnerable to an increase in underweight was different from that for overweight. There were substantial regional disparities in the age trajectories of childhood overweight and underweight. Whereas the analyses suggest that the dual burden of nutritional problems (the coexistence of overweight and underweight) in China is more like two sides of a coin than two separate health issues, the critical age period for intervening in childhood overweight is different from that of childhood underweight. Geographical indicators of childhood obesity in China deserve further attention.

The effects of total knee arthroplasty on physical functioning and health among the under age 65 population.

OBJECTIVES: This study examined the effects of total knee arthroplasty on six measures of physical functioning, self-rated health, pain, earnings, and employment status among US adults aged 51 to 63 years at baseline. METHODS: Data came from the Health and Retirement Study, a nationally representative longitudinal study conducted biannually. The analysis sample consisted of individuals aged 51 to 63 years at baseline with arthritis who were resurveyed at 2-year intervals from 1996 to 2010. Propensity score matching was used to compare outcomes of persons receiving total knee arthroplasty (TKA) with those of matched controls. Six measures of physical functioning were examined: lower-body mobility problems, instrumental activities of daily living limitations, activities of daily living limitations, and large muscle, fine motor, and gross motor limitations. Self-rated health and pain were also examined. The two employment-related outcomes were earnings and employment status. RESULTS: Receipt of TKA was associated with better outcomes for several measures of physical functioning, especially mobility limitations, pain, and self-rated health. Receipt of TKA was not associated with increased earnings or employment. CONCLUSIONS: Receipt of TKA yields important improvements in physical function among persons with an arthritis diagnosis who received the procedure before reaching the age of 65 years. This study contributes to knowledge about the benefits of TKA in a community setting among nonelderly recipients of TKA.

Assessing the relationship among urban trees, nitrogen dioxide, and respiratory health.

Modeled atmospheric pollution removal by trees based on eddy flux, leaf, and chamber studies of relatively few species may not scale up to adequately assess landscape-level air pollution effects of the urban forest. A land use regression (LUR) model (R(2) = 0.70) based on NO2 measured at 144 sites in Portland, Oregon (USA), after controlling for roads, railroads, and elevation, estimated every 10 ha (20%) of tree canopy within 400 m of a site was associated with a 0.57 ppb decrease in NO2. Using BenMAP and a 200 m resolution NO2 model, we estimated that the NO2 reduction associated with trees in Portland could result in significantly fewer incidences of respiratory problems, providing a $7 million USD benefit annually. These in-situ urban measurements predict a significantly higher reduction of NO2 by urban trees than do existing models. Further studies are needed to maximize the potential of urban trees in improving air quality.