Organic Geochemical Characteristics of Core Samples from Central Primorsk-Emba Province, Precaspian Basin, Kazakhstan

The Primorsk-Emba province is one of the main oil and gas region of the Precaspian basin. The resources of the Primorsk-Emba oil and gas region range from 5 to 12 billion tons of oil and from 2 to 6 trillion m³ of natural gas. This study primarily concentrates on investigating the organic geochemistry and petroleum geology characteristics of sedimentary units that generated oil in the central Primorsk-Emba province. 20 core samples taken from the Jurassic units in the western part of the study area are characterized by organic matter amount, hydrocarbon production potential, type of organic matter, maturity of organic matter. According to the Rock-Eval results Jurassic aged rocks generally have a petroleum potential ranging from weak to excellent, the organic matter is between Type II (oil prone), Type II-III (gas-oil prone) and Type III (gas prone), and the degree of maturation is immature-mature stage. Oil extracts were characterized by geochemical methods including Gas Chromatography (GC) and Gas Chromatography–Mass Spectrometry (GC–MS). n-alkanes and isoprenoids were evaluated by High-Resolution Gas Chromatography (GC-HR), aromatic hydrocarbons were evaluated by Low Thermal Mass Gas Chromatography (GC-LTM), terpanes (hopanes), steranes / diasteranes and aromatic hydrocarbons were evaluated by Gas Chromatography-Mass Spectrometry (GC-MS). The GC and GC-MS data obtained, it has been determined whether the paleoenvironment characteristics of the study area, hydrocarbon potential, type of kerogen, maturity level of organic matter and whether it is affected by biodegradation. Distribution of n-alkanes in the GC showed that no biodegradation was observed in analyzed samples, source rock deposited in a marine environment under reducing conditions and an organic matter that occurred were generated by marine carbonates. Based on maturity parameters, studied oils are mature and located on the oil generation window. According to biomarker age parameters C28 / C29 and norcholestane (NCR)/nordiacholestane (NDR) samples are generally Mesozoic (Triassic-Jurassic- Cretaceous) origin, nevertheless there are also levels corresponding to the Paleozoic (Permian) late stages.

Comparison of Point-of-Care Testing and Hospital-Based Methods in Screening for Potential Type 2 Diabetes Mellitus and Abnormal Glucose Regulation in a Dental Setting

This study aimed to compare the screening methods between point-of-care (POC) testing and hospital-based methods for potential type 2 DM and abnormal glucose regulation (AGR) in a dental setting. A total of 274 consecutive subjects who attended the Faculty of Dentistry, Mahidol University, Bangkok, Thailand, were selected. Demographic data were collected. HbA1c was assessed using a finger prick blood sample and analyzed with a point-of-care (POC) testing machine (DCA Vantage®). Hyperglycemia was defined as POC HbA1c ≥ 5.7%. Random blood glucose (RBG) was also evaluated using a glucometer (OneTouch® SelectSimple™) and hyperglycemia was defined as RBG ≥ 110 mg/dl or ≥140 mg/dl. The subjects were then sent for laboratory measurements for fasting plasma glucose (FPG) and HbA1c. The prevalence of AGR (defined as FPG ≥ 100 mg/dl or laboratory HbA1c ≥ 5.7%) and potential type 2 DM (defined as FPG ≥ 126 mg/dl or laboratory HbA1c ≥ 6.5%) among subjects was calculated and receiver operating characteristic (ROC) analysis was performed using FPG and HbA1c for the diagnosis of AGR and potential type 2 DM. The prevalence of hyperglycemia defined as POC HbA1c ≥ 5.7%, RBG ≥ 110 mg/dl, and RBG ≥ 140 mg/dl was 49%, 63%, and 32%, respectively. After the evaluation using laboratory measurements, the prevalence of AGR was 25% and 17% using laboratory FPG and HbA1c criteria, respectively. Based on the ROC curves, the performances of POC HbA1c and RBG in predicting FPG-defined potential type 2 DM were high (AUC = 0.99; 95% CI 0.98–0.99 and AUC = 0.94; 95% CI 0.86–1.0, respectively) but lower in predicting AGR (AUC = 0.72; 95% CI 0.67–0.78 and AUC = 0.65; 95% CI 0.59–0.70, respectively). This study suggested that POC testing might be a potential tool for screening of subjects with potential type 2 DM in a dental setting.