82 research outputs found
Epiphreatic caves in Niah karst tower (NW Borneo): occurrence, morphology and hydrogeochemistry
Epiphreatic caves develop close to the water table at the boundary between vadose and phreatic karst zones. The recognition of their former existence and position in uplifted limestone regions can inform on phases of uplift, base level lowering and rate of vertical deepening of the karst. Hence, epiphreatic caves and the karst processes that form them are of specific interest. Although the large and spectacular caves of Niah have been subject of much research and interest, the existence of small epiphreatic caves at the foot of the karst towers has not previously been documented in this region of NW Borneo. The study documents and reports an epiphreatic cave passage at water table elevation in the Painted Cave karst tower where several large caves are also known. The semi-flooded passage is over 480 m long and traverses the tower from east to west, intersecting other much larger vadose caves. The epiphreatic flow path is characterized by a number of sinking streams and resurgences as well as several sharp bends in the passage indicating joint control. As an initial attempt this study was undertaken to correlate the water chemistry along the cave path to understand the geomorphological controls. A preliminary campaign of water sampling was carried out with samples collected at ten locations along the path of the cave stream and analyzed for pH, EC, TDS, DO, Eh, major ions, nutrients and trace metals. The results show that dissolution of host rock and leaching of organic matter are the dominant controlling factors for the geochemistry of surface water along the cave stream passage. During dry conditions the water was under-saturated for carbonate minerals but not aggressive suggesting that most dissolution and erosion occurs during flood conditions. This is supported by the morphology of the passages and features of the rock wall both inside the caves and at the foot of the karst tower. Key words: Karst, Niah cave, Epiphreatic, Hydrogeochemistry, water table.Jame epifreatične cone v kraškem stolpu Niah (severozahodni Borneo): pojavnost, morfologija in hidrogeokemija Epifratične jame nastajajo na meji med vadozno in freatično cono. Prepoznavanje epifreatičnih elementov v bloku dvignjenega masiva nam omogoča razbrati faze dvigovanja masiva oz. spuščanja erozijske baze, zato so epifreatične jame in procesi še posebno zanimivi. Čeprav so o jamah stolpa Niah opravili številne študije, nobena od teh ne obravnava epifreatičnih jam ob vznožju kraškega stolpa. Ta študija obravnava epifreatične rove na ravni vodne gladine v stolpu Painted Cave v severozahodnem Borneu, kjer sicer poznamo več velikih jam. Delno potopljen rov je dolg več kot 480 m in preči stolp od vzhoda proti zahodu ter pri tem seka še več drugih, veliko večjih vadoznih jam. Epifreatični tok je povezan z več ponikalnicami in izviri, zanj so značilne nagle spremembe smeri, ki sledi vodilnim razpokam. Namen študije je povezati kemijo vode vzdolž toka in aktivne geomorfološke dejavnike. Vzorčenje in analize vode na desetih lokacijah so dali podatke o pH, električni prevodnosti, skupni raztopljeni snovi (TDS), raztopljenem kisiku, Eh ter o koncentraciji glavnih ionov, hranil in kovin v sledeh. Rezultati so pokazali, da sta raztapljanje matične kamnine in izpiranje organskih snovi prevladujoča dejavnika geokemije vode v kanalu. V sušnem obdobju je voda rahlo nenasičena na kalcit, a je agresivnost majhna, kar kaže na to, da glavna faza razvoja poteka v poplavnih obdobjih. To potrjujejo tudi morfologija rova in jamske skalne oblike v jami in ob vznožju kraškega stolpa.Ključne besede: kras, jama Niah, epifreatična cona, hidrogeokemija, vodna površina.
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A nutrigenetic approach to investigate the relationship between metabolic traits and vitamin D status in an Asian Indian population
Studies in Asian Indians have examined the association of metabolic traits with vitamin D status. However, findings have been quite inconsistent. Hence, we aimed to explore the relationship between metabolic traits and 25-hydroxyvitamin D [25(OH)D] concentrations. We investigate whether this relationship was modified by lifestyle factors using a nutrigenetic approach in 545 Asian Indians randomly selected from the Chennai Urban Rural Epidemiology Study (219 normal glucose tolerant individuals, 151 with pre-diabetes and 175 individuals with type 2 diabetes). A metabolic genetic risk score (GRS) was developed using five common metabolic disease-related genetic variants. There was a significant interaction between metabolic GRS and carbohydrate intake (energy%) on 25(OH)D (Pinteraction = 0.047). Individuals consuming a low carbohydrate diet (≤62%) and those having lesser number of metabolic risk alleles (GRS ≤ 1) had significantly higher levels of 25(OH)D (p = 0.033). Conversely, individuals consuming a high carbohydrate diet despite having lesser number of risk alleles did not show a significant increase in 25(OH)D (p = 0.662). In summary, our findings show that individuals carrying a smaller number of metabolic risk alleles are likely to have higher 25(OH)D levels if they consume a low carbohydrate diet. These data support the current dietary carbohydrate recommendations of 50%–60% energy suggesting that reduced metabolic genetic risk increases 25(OH)D
Metal concentrations in sediments from tourist beaches of Miri City, Sarawak, Malaysia (Borneo Island)
Forty-three sediment samples were collected from the beaches of Miri City, Sarawak, Malaysia to identify the enrichment of partially leached trace metals (PLTMs) from six different tourist beaches. The samples were analyzed for PLTMs Fe, Mn, Cr, Co, Cu, Ni, Pb, Sr and Zn. The concentration pattern suggest that the southern side of the study area is enriched with Fe (1821–6097 μg g−1), Mn (11.57–90.22 μg g−1), Cr (51.50–311 μg g−1), Ni (18–51 μg g−1), Pb (8.81–84.05 μg g−1), Sr (25.95–140.49 μg g−1) and Zn (12.46–35.04 μg g−1). Compared to the eco-toxicological values, Cr > Effects range low (ERL), Lowest effect level (LEL), Severe effect level (SEL); Cu > Unpolluted sediments, ERL, LEL; Pb > Unpolluted sediments and Ni > ERL and LEL. Comparative results with other regions indicate that Co, Cr, Cu, Ni and Zn are higher, indicating an external input rather than natural process
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Evidence for the association between FTO gene variants and vitamin B12 concentrations in an Asian Indian population
Background
Low vitamin B12 concentrations have been associated with major clinical outcomes, including adiposity, in Indian populations. The Fat mass and obesity-associated gene (FTO) is an established obesity-susceptibility locus; however, it remains unknown whether it influences vitamin B12 status. Hence, we investigated the association of two previously studied FTO polymorphisms with vitamin B12 concentrations and metabolic disease-related outcomes and examined whether these associations were modified by dietary factors and physical activity.
Methods
A total of 176 individuals with type 2 diabetes, 152 with pre-diabetes, and 220 normal glucose-tolerant individuals were randomly selected from the Chennai Urban Rural Epidemiology Study. Anthropometric, clinical, and biochemical investigations, which included body mass index (BMI), waist circumference, vitamin B12, homocysteine, and folic acid were measured. A validated food frequency questionnaire was used for dietary assessment and self-reported physical activity measures were collected. An unweighted genetic risk score (GRS) was calculated for two FTO single-nucleotide polymorphisms (rs8050136 and rs2388405) by summation of the number of risk alleles for obesity. Interaction analyses were performed by including the interaction terms in the regression model.
Results
The GRS was significantly associated with increased BMI (P = 0.009) and risk of obesity (P = 0.023). Individuals carrying more than one risk allele for the GRS had 13.13% lower vitamin B12 concentrations, compared to individuals carrying zero risk alleles (P = 0.018). No associations between the GRS and folic acid and homocysteine concentrations were observed. Furthermore, no statistically significant GRS-diet or GRS-physical activity interactions with vitamin B12, folic acid, homocysteine or metabolic-disease outcomes were observed.
Conclusion
The study shows for the first time that a genetic risk score using two FTO SNPs is associated with lower vitamin B12 concentrations; however, we did not identify any evidence for the influence of lifestyle factors on this association. Further replication studies in larger cohorts are warranted to investigate the association between the GRS and vitamin B12 concentrations
Physical activity patterns and gestational diabetes outcomes – The wings project
AbstractObjectiveTo compare physical activity (PA) patterns in pregnant woman with and without gestational diabetes (GDM) and to assess the effects of an exercise intervention on change in PA patterns, blood glucose levels and pregnancy outcomes in GDM women.MethodsFor the first objective, PA patterns were studied in 795 pregnant women with and without GDM. For the second objective, the Women in India with Gestational Diabetes Strategy-Model of Care (WINGS-MOC) intervention were evaluated in 151 women out of 189 with GDM. PA was assessed using a validated questionnaire and a pedometer. Changes in PA patterns, glycemic parameters and neonatal outcomes were evaluated.ResultsOverall, only 10% of pregnant women performed recommended levels of PA. Women with GDM were significantly more sedentary compared to those without GDM (86.2 vs. 61.2%, p<0.001). After the MOC was implemented in women with GDM, there was a significant improvement in PA and a decrease in sedentary behaviour amongst women (before MOC, moderate activity: 15.2%, sedentary: 84.8% vs. after MOC-moderate: 26.5%, sedentary: 73.5%; p<0.001), and an increase in their daily step count from 2206/day to 2476/day (p<0.001). Fasting 1 and 2-h postprandial glucose values significantly decreased (p<0.001 for all). Sedentary behaviour was associated with a fourfold higher risk (p=0.02), and recreational walking with 70% decreased risk, of adverse neonatal outcomes (p=0.04) after adjusting for potential confounders.ConclusionsPA levels are inadequate amongst this group of pregnant women studied i.e. those with and without GDM. However, a low-cost, culturally appropriate MOC can bring about significant improvements in PA in women with GDM. These changes are associated with improved glycemic control and reduction in adverse neonatal outcomes
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Circulating adiponectin mediates the association between omentin gene polymorphism and cardiometabolic health in Asian Indians
Background: Plasma omentin levels have been shown to be associated with circulating adiponectin concentrations and cardiometabolic disease-related outcomes. In this study, we aim to examine the association of omentin gene polymorphism with serum adiponectin levels and cardiometabolic health status using a genetic approach and investigate whether these associations are modified by lifestyle factors.
Methods: The study included 945 normal glucose tolerant and 941 unrelated individuals with type 2 diabetes randomly selected from the Chennai Urban Rural Epidemiology Study (CURES), in southern India. Study participants were classified into cardiometabolically healthy and unhealthy, where cardiometabolically healthy were those without hypertension, diabetes, and dyslipidemia. Fasting serum adiponectin levels were measured by radioimmunoassay. The omentin A326T (rs2274907) single nucleotide polymorphism (SNP) was screened by polymerase chain reaction-restriction fragment length polymorphism and direct sequencing.
Results: The ‘A’ allele of the omentin SNP was significantly associated with lower adiponectin concentrations after adjusting for age, sex, body mass index (BMI), waist circumference (WC) and cardiometabolic health status (p=1.90 x 10-47). There was also a significant association between circulating adiponectin concentrations and cardiometabolic health status after adjusting for age, sex, BMI, WC and Omentin SNP (p=7.47x10-10). However, after adjusting for age, sex, BMI, WC and adiponectin levels, the association of ‘A’ allele with cardiometabolic health status disappeared (p=0.79) suggesting that adiponectin serves as a mediator of the association between omentin SNP and cardiometabolic health status. There were no significant interactions between the SNP and dietary factors on adiponectin levels and cardiometabolic health status (p>0.25, for all comparisons).
Conclusions: Our findings show that adiponectin might function as a mechanistic link between omentin SNP and increased risk of cardiometabolic diseases independent of common and central obesity in Asian Indians. Further studies are required to confirm the molecular mechanisms involved in this triangular relationship between omentin gene, adiponectin and cardiometabolic diseases
Measuring progress from 1990 to 2017 and projecting attainment to 2030 of the health-related Sustainable Development Goals for 195 countries and territories: a systematic analysis for the Global Burden of Disease Study 2017
Background: Efforts to establish the 2015 baseline and monitor early implementation of the UN Sustainable Development Goals (SDGs) highlight both great potential for and threats to improving health by 2030. To fully deliver on the SDG aim of “leaving no one behind”, it is increasingly important to examine the health-related SDGs beyond national-level estimates. As part of the Global Burden of Diseases, Injuries, and Risk Factors Study 2017 (GBD 2017), we measured progress on 41 of 52 health-related SDG indicators and estimated the health-related SDG index for 195 countries and territories for the period 1990–2017, projected indicators to 2030, and analysed global attainment. Methods: We measured progress on 41 health-related SDG indicators from 1990 to 2017, an increase of four indicators since GBD 2016 (new indicators were health worker density, sexual violence by non-intimate partners, population census status, and prevalence of physical and sexual violence [reported separately]). We also improved the measurement of several previously reported indicators. We constructed national-level estimates and, for a subset of health-related SDGs, examined indicator-level differences by sex and Socio-demographic Index (SDI) quintile. We also did subnational assessments of performance for selected countries. To construct the health-related SDG index, we transformed the value for each indicator on a scale of 0–100, with 0 as the 2\ub75th percentile and 100 as the 97\ub75th percentile of 1000 draws calculated from 1990 to 2030, and took the geometric mean of the scaled indicators by target. To generate projections through 2030, we used a forecasting framework that drew estimates from the broader GBD study and used weighted averages of indicator-specific and country-specific annualised rates of change from 1990 to 2017 to inform future estimates. We assessed attainment of indicators with defined targets in two ways: first, using mean values projected for 2030, and then using the probability of attainment in 2030 calculated from 1000 draws. We also did a global attainment analysis of the feasibility of attaining SDG targets on the basis of past trends. Using 2015 global averages of indicators with defined SDG targets, we calculated the global annualised rates of change required from 2015 to 2030 to meet these targets, and then identified in what percentiles the required global annualised rates of change fell in the distribution of country-level rates of change from 1990 to 2015. We took the mean of these global percentile values across indicators and applied the past rate of change at this mean global percentile to all health-related SDG indicators, irrespective of target definition, to estimate the equivalent 2030 global average value and percentage change from 2015 to 2030 for each indicator. Findings: The global median health-related SDG index in 2017 was 59\ub74 (IQR 35\ub74–67\ub73), ranging from a low of 11\ub76 (95% uncertainty interval 9\ub76–14\ub70) to a high of 84\ub79 (83\ub71–86\ub77). SDG index values in countries assessed at the subnational level varied substantially, particularly in China and India, although scores in Japan and the UK were more homogeneous. Indicators also varied by SDI quintile and sex, with males having worse outcomes than females for non-communicable disease (NCD) mortality, alcohol use, and smoking, among others. Most countries were projected to have a higher health-related SDG index in 2030 than in 2017, while country-level probabilities of attainment by 2030 varied widely by indicator. Under-5 mortality, neonatal mortality, maternal mortality ratio, and malaria indicators had the most countries with at least 95% probability of target attainment. Other indicators, including NCD mortality and suicide mortality, had no countries projected to meet corresponding SDG targets on the basis of projected mean values for 2030 but showed some probability of attainment by 2030. For some indicators, including child malnutrition, several infectious diseases, and most violence measures, the annualised rates of change required to meet SDG targets far exceeded the pace of progress achieved by any country in the recent past. We found that applying the mean global annualised rate of change to indicators without defined targets would equate to about 19% and 22% reductions in global smoking and alcohol consumption, respectively; a 47% decline in adolescent birth rates; and a more than 85% increase in health worker density per 1000 population by 2030. Interpretation: The GBD study offers a unique, robust platform for monitoring the health-related SDGs across demographic and geographic dimensions. Our findings underscore the importance of increased collection and analysis of disaggregated data and highlight where more deliberate design or targeting of interventions could accelerate progress in attaining the SDGs. Current projections show that many health-related SDG indicators, NCDs, NCD-related risks, and violence-related indicators will require a concerted shift away from what might have driven past gains—curative interventions in the case of NCDs—towards multisectoral, prevention-oriented policy action and investments to achieve SDG aims. Notably, several targets, if they are to be met by 2030, demand a pace of progress that no country has achieved in the recent past. The future is fundamentally uncertain, and no model can fully predict what breakthroughs or events might alter the course of the SDGs. What is clear is that our actions—or inaction—today will ultimately dictate how close the world, collectively, can get to leaving no one behind by 2030
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