Research on deep geological structure and forecasting of some areas with petroleum prospects in the Red river delta coastal strip according to geophysical data

The coastal areas of the Red River Delta are the transition areas from the continent to the sea and have great mineral prospects, especially petroleum prospects. In this area, a lot of topics and projects in geology and geophysics have been conducted for many different purposes such as studying the deep structure, tectonic - geological features, seismic reflection - refraction to identify petroleum traps in the Cenozoic sediments... However there are very few studies on deep structure features, using the results of processing and meta-analysis of gravity, magnetotelluric, tectonic - geological data to detect the direct and indirect relations to the formation of structures with petroleum potential. The authors have researched, tested and applied an appropriate methodology of processing and analysis, to overcome the shortfall of gravity data as well as the nonhomogeneity in details of seismic and geophysical surveys. The obtained results are semi-quantitative and qualitative characteristics of structure of deep boundary surfaces, structural characteristics of fault systems and their distribution in the study area, calculation of the average rock density of pre-Cenozoic basement... From these results, the authors established the zoning map of the areas with petroleum potential in the Red river delta coastal strip according to geophysical data

Serum free light-chain concentration and relationship with some characteristics of patients with multiple myeloma

Introduction: Quantifying serum free light-chain is a valuable test to determine the risk at the time of diagnosis, assess the response to treatment, and monitor the recurrence of multiple myeloma. Objective: To investigate the characteristics of serum free light-chain concentration and its relationship with some clinical and subclinical characteristics in patients with multiple myeloma. Methods: Descriptive, retrospective, non-controlled study was conducted, in 74 patients with multiple myeloma. All patients were completed with quantitative tests serum free light-chain κ, and serum free light-chain λ. Results: Intact immunoglobulin multiple myeloma accounted for most patients (81%). Most patients had abnormal serum free light-chain at the time of diagnosis (98.6%). High serum free light-chain concentration was correlated with M protein concentration > 3 g/dL (p< 0.05) and there was no statistically significant correlation between high serum free light-chain and other clinical and subclinical features. Conclusion: Most patients with multiple myeloma have an elevated serum free light-chain at admission time. Correlation of high serum free light-chain with increased serum M protein was noted

BACH HO FIELD GEOLOGICAL FEATURES IDENTIFICATION USING WELL LOGGING DATA

Link for citation: Nguyen Xuan Kha, Pham Xuan Son, Hoang Van Quy, Nguyen Tuan, Truong Quoc Thanh, Mai Huu Xuan, Tran Van Xuan.  Bach ho field geological features identification using  well logging data. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 7, рр. 35-42. In Rus. The relevance. Well geophysics is considered as a typical method that can assist in determining the petrophysics properties of reservoirs and further location of the petroleum product-containing reservoirs. For reservoirs formed from fractured basement rock, studies on the petrophysics properties of fracture zones can contribute to the identification of petroleum products. The main aim. The study applied the cross-plotting method based on raw well-logging data to identify the possible correlation between the gamma-ray logging with well-logging including neutron porosity, sonic transient time, and bulk density in three wells (BH-433, BH-809, and BH-905) of Bach Ho field in the Cuu Long Basin, Vietnam. Methods. To deploy this study, well-logging data were integrated into formation of micro images and neutro, speed of sound, and density of the basement at the surveyed reservoir positions. Results. The results indicated that granite in the investigated zones responds to the two tight value ranges (no-oil exist zones) neutro (0,000–0,100) and speed of sound (46–64), and neutro (0,000–0,100) and density (2,375–2,750) while the value ranges deviate from 0,000–0,100, 46–64, and 2,375–2,750, respectively for neutro, speed of sound, and density are closely related to the good permeability and porosity zones (oil exist zones). Based on the findings, it can be confirmed that the cross-plotting analysis has contributed positively to the initial assessment of potential ranges of the oil reservoirs in Bach Ho field. The application of the cross-plotting method will contribute to enhancing the predictability of oil and gas in the reservoirs

Facile Synthesis of Carbon Quantum Dots by Plasma-liquid Interaction Method

Carbon quantum dots (CQDs) are a novel type of fluorescent nano-materials with various unique properties. They are recently attracting enormous interest due to their superiority in water solubility, chemical inertness, low toxicity, ease of functionalization as well as resistance to photo-bleaching and potential applications in biomedical indication, photo-catalysis, energy conversion, optoelectronics, and sensing. In this work, we present a facile and environmentally friendly synthesis of CQDs based on plasma - liquid interaction method. This is a single-step method and does not use toxic chemicals. The size distribution of obtained CQDs is rather uniform at approximately 3 nm. The emission peak of CQDs shifts from 427 nm to 523 nm as the excitation wavelength is varied from 340 nm to 460 nm. The non-equilibrium reactive chemistry of plasma liquid interaction is responsible for acceleration of the CQDs formation process

pH-Dependence of the Optical Bio-sensor Based on DNA-carbon Nanotube

In 2006, Daniel A. Heller et al. [1] demonstrated that carbon nanotubes (CNNTs) wrapped with DNA can be placed inside living cells and detect trace amounts of harmful contaminants using near infrared light. This discovery could lead to new types of optical sensors and biomarkers at the sub cellular level. The working principle of this optical bio-sensor from DNA and CNNTs can be explained by a simple theoretical model which was introduced in [3]. In this paper, the pH-dependence of DNA and the pH-dependence of solution around CNNTs are shown by using data analysis method. By substituting them into the same model, the pH-dependence of DNA-wrapped CNNTs was elicited in this paper. The range of parameters for workable conditions of this bio-sensor was indicated that the solution should have pH from 6 to 9 and the concentration of ions should be more than a critical value. These results are according to the experimental data and the deduction about pH and salt concentration in solution. They are very useful as using such a new bio-sensor like this in living environment

Van Der Waals and Casimir Interactions of Some Graphene, Material Plate and CNTs Systems

The Van der Waals and Casimir interactions between graphene and a material plate are studied by using the Lifshitz theory and approximate expressions for the free energy and force. The reflection properties of electromagnetic oscillations on graphene are governed by specific boundary conditions imposed on the infinitely thin positively charged plasma sheet, carrying a continuous fluid with some mass and charge density. The obtained formulas are applied to the cases of a graphene interacting with Au plate. We calculated also the Casimir interaction between carbon nanotube single wall and Au plate. The comparision with other recently obtained theoretical results are made and the generalizations to more complicated carbon nanostructures are discussed

Respiratory viruses in individuals with a high frequency of animal exposure in southern and highland Vietnam

Active surveillance for zoonotic respiratory viruses is essential to inform the development of appropriate interventions and outbreak responses. Here we target individuals with a high frequency of animal exposure in Vietnam. Three-year community-based surveillance was conducted in Vietnam during 2013-2016. We enrolled a total of 581 individuals (animal-raising farmers, slaughterers, animal-health workers, and rat traders), and utilized reverse transcription-polymerase chain reaction to detect 15 common respiratory viruses in pooled nasal-throat swabs collected at baseline or acute respiratory disease episodes. A respiratory virus was detected in 7.9% (58 of 732) of baseline samples, and 17.7% (136 of 770) of disease episode samples (P <.001), with enteroviruses (EVs), rhinoviruses and influenza A virus being the predominant viruses detected. There were temporal and spatial fluctuations in the frequencies of the detected viruses over the study period, for example, EVs and influenza A viruses were more often detected during rainy seasons. We reported the detection of common respiratory viruses in individuals with a high frequency of animal exposure in Vietnam, an emerging infectious disease hotspot. The results show the value of baseline/control sampling in delineating the causative relationships and have revealed important insights into the ecological aspects of EVs, rhinoviruses and influenza A and their contributions to the burden posed by respiratory infections in Vietnam.Peer reviewe

Assessment of aflatoxin B1 contamination in rice and maize

Introduction: Aflatoxins B1 are among the most common poisonous mycotoxins produced by certain fungi that harm animals and crops. Mycotoxins can cause a variety of adverse health effects and pose a serious health threat to humans. The Maximum Residue Limits of aflatoxin B1 in processed cereals and ingredients are 2 parts per billion (ppb) and 5 ppb, respectively. Objectives: To evaluate the status of aflatoxin B 1 contamination in rice, corn and staple food produced in Ha Giang province compared with the maximum permitted levels. Methods: A total of 210 rice and maize samples were analyzed to quantify the level of aflatoxin B1. Analysis of mycotoxins was conducted by High Performance Liquid Chromatography using a fluorescence detector. Results: It was found that rice, rice products, maize, and maize products had a mean aflatoxin B1 content of 1.79 ppb, 2.55 ppb, 2.19 ppb, and 6.35 ppb, respectively. The results also showed that 71.9% of samples were contaminated with mycotoxins, and 14.28% of samples exceeded the maximum allowable limit. Conclusion: The concentration of aflatoxin B1 in 14.28% of the samples are over permissible limits by nationwide regulations

Redondoviridae: High Prevalence and Possibly Chronic Shedding in Human Respiratory Tract, But No Zoonotic Transmission

Redondoviridae is a recently discovered DNA virus family consisting of two species, vientovirus and brisavirus. Here we used PCR amplification and sequencing to characterize redondoviruses in nasal/throat swabs collected longitudinally from a cohort of 58 individuals working with animals in Vietnam. We additionally analyzed samples from animals to which redondovirus DNA-positive participants were exposed. Redondoviruses were detected in approximately 60% of study participants, including 33% (30/91) of samples collected during episodes of acute respiratory disease and in 50% (29/58) of baseline samples (with no respiratory symptoms). Vientovirus (73%; 24/33) was detected more frequently in samples than brisaviruses (27%; 9/33). In the 23 participants with at least 2 redondovirus-positive samples among their longitudinal samples, 10 (43.5%) had identical redondovirus replication-gene sequences detected (sampling duration: 35–132 days). We found no identical redondovirus replication genes in samples from different participants, and no redondoviruses were detected in 53 pooled nasal/throat swabs collected from domestic animals. Phylogenetic analysis described no large-scale geographical clustering between viruses from Vietnam, the US, Spain, and China, indicating that redondoviruses are highly genetically diverse and have a wide geographical distribution. Collectively, our study provides novel insights into the Redondoviridae family in humans, describing a high prevalence, potentially associated with chronic shedding in the respiratory tract with lack of evidence of zoonotic transmission from close animal contacts. The tropism and potential pathogenicity of this viral family remain to be determined

Redondoviridae: High Prevalence and Possibly Chronic Shedding in Human Respiratory Tract, But No Zoonotic Transmission

Redondoviridae is a recently discovered DNA virus family consisting of two species, vientovirus and brisavirus. Here we used PCR amplification and sequencing to characterize redondoviruses in nasal/throat swabs collected longitudinally from a cohort of 58 individuals working with animals in Vietnam. We additionally analyzed samples from animals to which redondovirus DNA-positive participants were exposed. Redondoviruses were detected in approximately 60% of study participants, including 33% (30/91) of samples collected during episodes of acute respiratory disease and in 50% (29/58) of baseline samples (with no respiratory symptoms). Vientovirus (73%; 24/33) was detected more frequently in samples than brisaviruses (27%; 9/33). In the 23 participants with at least 2 redondovirus-positive samples among their longitudinal samples, 10 (43.5%) had identical redondovirus replication-gene sequences detected (sampling duration: 35–132 days). We found no identical redondovirus replication genes in samples from different participants, and no redondoviruses were detected in 53 pooled nasal/throat swabs collected from domestic animals. Phylogenetic analysis described no large-scale geographical clustering between viruses from Vietnam, the US, Spain, and China, indicating that redondoviruses are highly genetically diverse and have a wide geographical distribution. Collectively, our study provides novel insights into the Redondoviridae family in humans, describing a high prevalence, potentially associated with chronic shedding in the respiratory tract with lack of evidence of zoonotic transmission from close animal contacts. The tropism and potential pathogenicity of this viral family remain to be determined