Trace ambient levels of particulate mercury and its sources at a rural site near Delhi

To investigate the impact of burning postharvest crop residues in home stoves, PM2.5 samples (particulate matter with a diameter of <2.5 μm) were collected every 3 h at a rural site in Daejeon, Korea during the postharvest season in 2014. A high concentration of levoglucosan was observed with a peak value of 3.8 µg/m3 during the sampling period. The average mannosan/levoglucosan ratio (0.18) at the rural site during a severe BB episode (levoglucosan > 1 μg/m3) was similar to burnings of pepper stems (0.19) and bean stems (0.18) whereas the average OC/levoglucosan ratio (9.9) was similar to burning of pepper stems (10.0), implying that the severe BB episode was mainly attributed to burning of pepper stems. A very strong correlation was observed between levoglucosan and organic carbon (OC) (R2 = 0.81) during the entire sampling period, suggesting that the emission of organic aerosols at the rural site was strongly associated with the burning of crop residues in home stoves. The average mannosan/levoglucosan ratio (0.17 ± 0.06) in the rural area was similar to that in a nearby urban area in Daejeon (0.16 ± 0.04). It was concluded that crop residue burning in a home stove for space heating is one of the important sources of carbonaceous aerosols not only in a rural area but also in the urban area of Daejeon, Korea during the postharvest season.

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Salt Intake in Nigeria: a nationwide population survey

European Heart Journal ◽

10.1093/ehjci/ehaa946.2866 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

A.N Odili ◽

B.S Chori ◽

B Danladi ◽

P.C Nwakile ◽

J.O Ogedengbe ◽

...

Keyword(s):

Salt Intake ◽

Sodium Intake ◽

Population Analysis ◽

Cost Effective ◽

Rural Site ◽

Urban Site ◽

Funding Source ◽

Salt Reduction ◽

High Salt Intake ◽

The Impact

Abstract Background Population wide salt reduction programmes are cost effective strategies for control of cardiovascular diseases (CVDs). Obtaining a nationwide salt consumption data in a multi-cultural setting as Nigeria's is key for proper implementation and monitoring of such strategy. Methods We measured sodium in 24-hour urine of free-living adult Nigerians selected from an urban and a rural site each from the 6 geopolitical zones of Nigeria to evaluate patterns of salt intake and its associations with blood pressures (BP). Results Across the 12 sites, sodium intake ranged from 97.9 in the rural South-South to 210 mmol/day in the urban site of the same zone. Overall, the median (IQR) daily sodium intake was 143.5 (97.8) mmol; with higher (p=0.0028) levels among the urban 149.7 (113.8) compared to the rural 133.1 (105.2) dwellers. Overall, 20% of the subjects consumed less than the recommended 2g (86mmol) of sodium daily. After adjustment for age, sex and BMI; sodium intake and BP (systolic and diastolic) were positively associated in 8 out of the 12 sites; significantly so in 2 (p<0.05) for systolic. Within population analysis; which included 973 individuals, increasing sodium intake tended (not significantly) to increase SBP but decrease DBP. However, among subjects whose sodium intake was in excess of 257mmol/day, a 100 mmol/day increase in sodium intake was significantly (p=0.04) associated with a 3.3 mmHg increase in SBP. Conclusion Salt intake among Nigerians is higher than the recommended. The impact of sodium intake on BP appears to be evident only among individuals with high salt intake. Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): Wellcome Trust

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Effect of water on the electroresponsive structuring and friction in dilute and concentrated ionic liquid lubricant mixtures

Physical Chemistry Chemical Physics ◽

10.1039/d0cp05110a ◽

2020 ◽

Vol 22 (48) ◽

pp. 28191-28201

Author(s):

Georgia A. Pilkington ◽

Rebecca Welbourn ◽

Anna Oleshkevych ◽

Seiya Watanabe ◽

Patricia Pedraz ◽

...

Keyword(s):

Atomic Force Microscopy ◽

Ionic Liquid ◽

Neutron Reflectivity ◽

Force Microscopy ◽

Liquid Lubricant ◽

Effect Of Water ◽

Atomic Force ◽

Ambient Levels

The influence of ambient levels of water on the electroresponsive interfacial structuring and nanofriction of ionic liquid lubricant mixtures has been investigated by neutron reflectivity and atomic force microscopy.

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Spatiotemporal distribution of light-absorbing carbon and its relationship to other atmospheric pollutants in Stockholm

Atmospheric Chemistry and Physics ◽

10.5194/acp-11-11553-2011 ◽

2011 ◽

Vol 11 (22) ◽

pp. 11553-11567 ◽

Cited By ~ 13

Author(s):

P. Krecl ◽

A. C. Targino ◽

C. Johansson

Keyword(s):

Exhaust Emissions ◽

Atmospheric Pollutants ◽

Spatiotemporal Variability ◽

Rural Site ◽

Strong Increase ◽

Population Exposure ◽

Emission Sources ◽

Vehicle Exhaust ◽

Urban Background ◽

Urban Sites

Abstract. Carbon-containing particles have deleterious effects on both Earth's climate and human health. In Europe, the main sources of light-absorbing carbon (LAC) emissions are the transport (67%) and residential (25%) sectors. Information on the spatiotemporal variability of LAC particles in urban areas is relevant for air quality management and to better diagnose the population exposure to these particles. This study reports on results of an intensive field campaign conducted at four sites (two kerbside stations, one urban background site and a rural station) in Stockholm, Sweden, during the spring 2006. Light-absorbing carbon mass (MLAC) concentrations were measured with custom-built Particle Soot Absorption Photometers (PSAP). The spatiotemporal variability of MLAC concentrations was explored by examining correlation coefficients (R), coefficients of divergence (COD), and diurnal patterns at all sites. Simultaneous measurements of NOx, PM10, PM2.5, and meteorological variables were also carried out at the same locations to help characterize the LAC emission sources. Hourly mean (± standard deviation) MLAC concentrations ranged from 0.36±0.50 at the rural site to 5.39±3.60 μg m−3 at the street canyon site. Concentrations of LAC between urban sites were poorly correlated even for daily averages (R<0.70), combined with highly heterogeneously distributed concentrations (COD>0.30) even at spatial scales of few kilometers. This high variability is connected to the distribution of emission sources and processes contributing to the LAC fraction at these sites. At urban sites, MLAC tracked NOx levels and traffic density well and mean MLAC/PM2.5 ratios were larger (26–38%) than at the background sites (4–10%). The results suggest that vehicle exhaust emissions are the main responsible for the high MLAC concentrations found at the urban locations whereas long-range transport (LRT) episodes of combustion-derived particles can generate a strong increase of levels at background sites. To decrease pollution levels at kerbside and urban background locations in Stockholm, we recommend abatement strategies that target reductions of vehicle exhaust emissions, which are the main contributors to MLAC and NOx concentrations.

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Establishing a postgraduate programme in nutritional epidemiology to strengthen resource capacity, academic leadership and research in the democratic republic of Congo

BMC Medical Education ◽

10.1186/s12909-021-02557-3 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Mapatano Mala Ali ◽

Lyn Haskins ◽

Vaughn John ◽

Anne Hatløy ◽

Silondile Luthuli ◽

...

Keyword(s):

Democratic Republic ◽

Democratic Republic Of Congo ◽

Lessons Learned ◽

Academic Leadership ◽

Nutritional Epidemiology ◽

Rural Site ◽

Educational Approach ◽

Financial Barriers ◽

Republic Of Congo ◽

Health And Nutrition

Abstract Background Low- and Middle-income countries (LMIC) face considerable health and nutrition challenges, many of which can be addressed through strong academic leadership and robust research translated into evidence-based practice. A North-South-South partnership between three universities was established to implement a master’s programme in nutritional epidemiology at the Kinshasa School of Public Health (KSPH), Democratic Republic of Congo (DRC). The partnership aimed to develop academic leadership and research capacity in the field of nutrition in the DRC. In this article we describe the educational approach and processes used, and discuss successes, challenges, and lessons learned. Methods Self-administered questionnaires, which included both open and closed questions, were sent to all graduates and students on the master’s programme to explore students’ experiences and perceptions of all aspects of the educational programme. Quantitative data was analysed using frequencies, and a thematic approach was used to analyse responses to open-ended questions. Results A two-year master’s programme in Nutritional Epidemiology was established in 2014, and 40 students had graduated by 2020. Key elements included using principles of authentic learning, deployment of students for an internship at a rural residential research site, and support of selected students with bursaries. Academic staff from all partner universities participated in teaching and research supervision. The curriculum and teaching approach were well received by most students, although a number of challenges were identified. Most students reported benefits from the rural internship experience but were challenged by the isolation of the rural site, and felt unsupported by their supervisors, undermining students’ experiences and potentially the quality of the research. Financial barriers were also reported as challenges by students, even among those who received bursaries. Conclusion The partnership was successful in establishing a Master Programme in Nutritional Epidemiology increasing the number of nutrition researchers in the DRC. This approach could be used in other LMIC settings to address health and nutrition challenges.

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A cross-sectional study measuring contact patterns using diaries in an urban and a rural community in South Africa, 2018

BMC Public Health ◽

10.1186/s12889-021-11136-6 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Jackie Kleynhans ◽

Stefano Tempia ◽

Meredith L. McMorrow ◽

Anne von Gottberg ◽

Neil A. Martinson ◽

...

Keyword(s):

South Africa ◽

Age Groups ◽

Cross Sectional Study ◽

Rural Site ◽

Urban Site ◽

Contact Rate ◽

Sectional Study ◽

Cross Sectional ◽

Contact Rates ◽

Contact Patterns

Abstract Background Describing contact patterns is crucial to understanding infectious disease transmission dynamics and guiding targeted transmission mitigation interventions. Data on contact patterns in Africa, especially South Africa, are limited. We measured and compared contact patterns in a rural and urban community, South Africa. We assessed participant and contact characteristics associated with differences in contact rates. Methods We conducted a cross-sectional study nested in a prospective household cohort study. We interviewed participants to collect information on persons in contact with for one day. We described self-reported contact rates as median number people contacted per day, assessed differences in contact rates based on participant characteristics using quantile regression, and used a Poisson model to assess differences in contact rates based on contact characteristics within age groups. We also calculated cumulative person hours in contact within age groups at different locations. Results We conducted 535 interviews (269 rural, 266 urban), with 17,252 contacts reported. The overall contact rate was 14 (interquartile range (IQR) 9–33) contacts per day. Those ≤18 years had higher contact rates at the rural site (coefficient 17, 95% confidence interval (95%CI) 10–23) compared to the urban site, for those aged 14–18 years (13, 95%CI 3–23) compared to < 7 years. No differences were observed for adults. There was a strong age-based mixing, with age groups interacting more with similar age groups, but also interaction of participants of all ages with adults. Children aged 14–18 years had the highest cumulative person hours in contact (116.3 rural and 76.4 urban). Conclusions Age played an important role in the number and duration of contact events, with children at the rural site having almost double the contact rate compared to the urban site. These contact rates can be utilized in mathematical models to assess transmission dynamics of infectious diseases in similar communities.

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