Improvement of Quantitative Evaluation of Rock Brittleness Based on Stress-Strain Curve

Accurate assessment of brittle of rock is the key to the transformation of oil and gas reservoirs. In view of this, Therefore, through literature research, summarized more than 30 kinds of  brittleness index, and analysis the limitations of the brittleness evaluation index. A new brittle evaluation index, based on the stress characteristics of the stress-strain curve, and considering the two kinds of rock breaking behavior, is proposed. And carry out uniaxial compression test to verify the evaluation index of brittleness. The test results show that the new brittle index can evaluate the two kinds of rock brittleness, which is more general and reliable than other indexes. The results have important significance to enrich and improve the existing evaluation methods of rock brittleness

Microbiota-Produced N-Formyl Peptide fMLF Promotes Obesity-Induced Glucose Intolerance.

The composition of the gastrointestinal microbiota and associated metabolites changes dramatically with diet and the development of obesity. Although many correlations have been described, specific mechanistic links between these changes and glucose homeostasis remain to be defined. Here we show that blood and intestinal levels of the microbiota-produced N-formyl peptide, formyl-methionyl-leucyl-phenylalanine, are elevated in high-fat diet-induced obese mice. Genetic or pharmacological inhibition of the N-formyl peptide receptor Fpr1 leads to increased insulin levels and improved glucose tolerance, dependent upon glucagon-like peptide 1. Obese Fpr1 knockout mice also display an altered microbiome, exemplifying the dynamic relationship between host metabolism and microbiota. Overall, we describe a new mechanism by which the gut microbiota can modulate glucose metabolism, providing a potential approach for the treatment of metabolic disease

Aggregate blood pressure responses to serial dietary sodium and potassium intervention: Defining responses using independent component analysis

BACKGROUND: Hypertension is a complex trait that often co-occurs with other conditions such as obesity and is affected by genetic and environmental factors. Aggregate indices such as principal components among these variables and their responses to environmental interventions may represent novel information that is potentially useful for genetic studies. RESULTS: In this study of families participating in the Genetic Epidemiology Network of Salt Sensitivity (GenSalt) Study, blood pressure (BP) responses to dietary sodium interventions are explored. Independent component analysis (ICA) was applied to 20 variables indexing obesity and BP measured at baseline and during low sodium, high sodium and high sodium plus potassium dietary intervention periods. A “heat map” protocol that classifies subjects based on risk for hypertension is used to interpret the extracted components. ICA and heat map suggest four components best describe the data: (1) systolic hypertension, (2) general hypertension, (3) response to sodium intervention and (4) obesity. The largest heritabilities are for the systolic (64 %) and general hypertension (56 %) components. There is a pattern of higher heritability for the component response to intervention (40–42 %) as compared to those for the traditional intervention responses computed as delta scores (24 %–40 %). CONCLUSIONS: In summary, the present study provides intermediate phenotypes that are heritable. Using these derived components may prove useful in gene discovery applications. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12863-015-0226-8) contains supplementary material, which is available to authorized users

Diabetes with kidney injury may change the abundance and cargo of urinary extracellular vesicles

BackgroundUrinary extracellular vesicles (uEVs) are derived from epithelia facing the renal tubule lumen in the kidney and urogenital tract; they may carry protein biomarkers of renal dysfunction and structural injury. However, there are scarce studies focusing on uEVs in diabetes with kidney injury.Materials and methodsA community-based epidemiological survey was performed, and the participants were randomly selected for our study. uEVs were enriched by dehydrated dialysis method, quantified by Coomassie Bradford protein assay, and adjusted by urinary creatinine (UCr). Then, they identified by transmission electron microscopy (TEM), nanoparticle track analysis (NTA), and western blot of tumor susceptibility gene 101.ResultsDecent uEVs with a homogeneous distribution were finally obtained, presenting a membrane-encapsulated structure like cup-shaped or roundish under TEM, having active Brownian motion, and presenting the main peak between 55 and 110 nm under NTA. The Bradford protein assay showed that the protein concentrations of uEVs were 0.02 ± 0.02, 0.04 ± 0.05, 0.05 ± 0.04, 0.07 ± 0.08, and 0.11 ± 0.15 μg/mg UCr, respectively, in normal controls and in prediabetes, diabetes with normal proteinuria, diabetes with microalbuminuria, and diabetes with macroproteinuria groups after adjusting the protein concentration with UCr by calculating the vesicles-to-creatinine ratio.ConclusionThe protein concentration of uEVs in diabetes with kidney injury increased significantly than the normal controls before and after adjusting the UCr. Therefore, diabetes with kidney injury may change the abundance and cargo of uEVs, which may be involved in the physiological and pathological changes of diabetes

Nanoscale pore characteristics of the Jurassic Dongyuemiao member lacustrine shale, Eastern Sichuan Basin, SW China: Insights from SEM, NMR, LTNA, and MICP experiments

The Jurassic Dongyuemiao Member is the most promising target for lacustrine shale gas exploration in Sichuan Basin. By integrating SEM, NMR, LTNA, and MICP experiments, and other basic measurements, the nanoscale pore category and structure and the corresponding controlling factors of Dongyuemiao lacustrine shale in Eastern Sichuan Basin are studied. The results denote that organic pores comprise primary pores within plant debris and secondary pores within bitumen. Inorganic pores are composed of intraparticle pores within calcite particles, intercrystalline pores between pyrite crystals, and interparticle pores between different minerals. The 4th Section lacustrine shale of Dongyuemiao Member has the best pore structure, exhibiting high organic pore proportion, large amounts of gas adsorption, and parallel plate-shaped pore morphology. Micropores (<2 nm) are the main contributors of the pore volume and surface area of Dongyuemiao lacustrine shale. Moreover, the enrichment of organic matter positively affects the formation of micropores and has no influence on the mesopore–macropore (>2 nm). Quartz does not significantly affect the nanoscale pore formation. The intraparticle pores within calcite particles constitute part of mesopore–macropore but not micropores. Clay minerals are conducive to the formation of micropores but play a negative role in the formation of mesopore–macropore

The future impact of population growth and aging on coronary heart disease in China: projections from the Coronary Heart Disease Policy Model-China

Background: China will experience an overall growth and aging of its adult population in coming decades. We used a computer model to forecast the future impact of these demographic changes on coronary heart disease (CHD) in China. Methods: The CHD Policy Model is a validated state-transition, computer simulation of CHD on a national scale. China-specific CHD risk factor, incidence, case-fatality, and prevalence data were incorporated, and a CHD prediction model was generated from a Chinese cohort study and calibrated to age-specific Chinese mortality rates. Disability-adjusted life years (DALYs) due to CHD were calculated using standard methods. The projected population of China aged 35–84 years was entered, and CHD events, deaths, and DALYs were simulated over 2000–2029. CHD risk factors other than age and case-fatality were held at year 2000 levels. Sensitivity analyses tested uncertainty regarding CHD mortality coding, the proportion of total deaths attributable to CHD, and case-fatality. Results: We predicted 7.8 million excess CHD events (a 69% increase) and 3.4 million excess CHD deaths (a 64% increase) in the decade 2020–2029 compared with 2000–2009. For 2030, we predicted 71% of almost one million annual CHD deaths will occur in persons ≥ 65 years old, while 67% of the growing annual burden of CHD death and disability will weigh on adults < 65 years old. Substituting alternate CHD mortality assumptions led to 17–20% more predicted CHD deaths over 2000–2029, though the pattern of increases in CHD events and deaths over time remained. Conclusion: We forecast that absolute numbers of CHD events and deaths will increase dramatically in China over 2010–2029, due to a growing and aging population alone. Recent data suggest CHD risk factor levels are increasing, so our projections may underestimate the extent of the potential CHD epidemic in China

Genome-wide association study on serum alkaline phosphatase levels in a Chinese population

Background: Serum alkaline phosphatase (ALP) is a complex phenotype influenced by both genetic and environmental factors. Recent Genome-Wide Association Studies (GWAS) have identified several loci affecting ALP levels; however, such studies in Chinese populations are limited. We performed a GWAS analyzing the association between 658,288 autosomal SNPs and serum ALP in 1,461 subjects, and replicated the top SNPs in an additional 8,830 healthy Chinese Han individuals. The interactions between significant locus and environmental factors on serum ALP levels were further investigated. Results: The association between ABO locus and serum ALP levels was replicated (P = 2.50 × 10-21, 1.12 × 10-56 and 2.82 × 10-27 for SNP rs8176720, rs651007 and rs7025162 on ABO locus, respectively). SNP rs651007 accounted for 2.15% of the total variance of serum ALP levels independently of the other 2 SNPs. When comparing our findings with previously published studies, ethnic differences were observed across populations. A significant interaction between ABO rs651007 and overweight and obesity was observed (FDR for interaction was 0.036); for individuals with GG genotype, those with normal weight and those who were overweight or obese have similar serum ALP concentrations; minor allele A of rs651007 remarkably reduced serum ALP levels, but this effect was attenuated in overweight and obese individuals. Conclusions: Our findings indicate that ABO locus is a major determinant for serum ALP levels in Chinese Han population. Overweight and obesity modifies the effect of ABO locus on serum ALP concentrations