bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantifying the Risks of Wellbore Failure During Drilling Operations Using Bayesian Algorithm
Authors: Adeyemi Emmanuel A. , Ogbe David O. , Wu Xingru
Published: August 2020

The wellbore integrity plays an important role in petroleum operations like drilling, well completion and production. Caliper, Electrical image logs, Acoustic televiewers (ATV) and Optical televiewers (OTV) are some of the devices currently used in the industries to identify breakouts. However, these techniques are restricted in applications. For instance, caliper sometimes indicates the effect of drill spiral grooves as borehole enlargement zones; poor resolution and complicated processing procedure limit the application of the electrical image logs. The ATV and OTV which give better outputs are not often used due to the high cost of installation and operation. These limitations necessitated a new approach to quantifying the wellbore instability. This research work focuses on data analytics and the development of the Bayesian Algorithm (with code in Python) to predict the wellbore failure probability using real-time pore pressure and fracture gradients data obtained from the wellbore using modified d-exponent.
Modelling the Scaling Tendency of Produced Water: A Case Study of Niger Delta Brown Field
Authors: Adeeyo Yisa , Onyeka Emeka , Etim Augusta , Brown Ernest , Ossai Onyebuchi , Udofia Ubong , Namtari Salihu
Published: August 2020

Most of the brown fields in Niger delta oil and gas province are experiencing decline in oil output coupled with increasing water production. This is more pronounced due to the mature fields having strong water drive. The management of this produced water has become very important as cost of handling such high volumes is unsustainable.

Most of the water management options include selective well completions, water shut-off, production rate control and produced water re-injection (PWRI). PWRI into the producing reservoir for the purpose of supporting the reservoir pressure and improving hydrocarbon sweep efficiency is a major benefit of the water injection activity. Other standard produced water management practices include disposal into depleted reservoir, deeper non oil-bearing reservoir or ocean.

Defining the process for the injection of produced water has posed a greater challenge to the optimization and management of oil reservoirs. This is not unconnected with adverse effects of the produced water on the reservoir properties when not properly treated. Such effects include but are not limited to scales and pore throat blockages leading to sand formation damage, reservoir souring, reduction in matrix permeability, fractures in the matrix caused by high water injection pressure.

In this work, representative samples were collected, and experimental measurements were made on three (3) flow stations produced water.

This study describes the water injection/disposal compatibility laboratory test results for scale formation modelling in the field with due consideration to the reservoir geology complexity and heterogeneity. Test and modelling results of mixes of produced water indicated the brine is supersaturated with magnesium carbonate (MgCO3) with scaling tendency much greater than one, fouling of the reservoir with H2S due to proliferation of Sulphate Reducing Bacteria (SRBs) and the attendant corrosion.

These results formed the basis for recommendations of the effective produced water treatment for water re-injection and disposal. This study will be of immense benefits to E & P companies operating in Niger Delta in particular, and Africa in general in their efforts to effectively manage produced water.
Supervised and Unsupervised Machine Learning Approach in Facies Prediction
Authors: Fadokun Daniel Oluwadara , Oshilike Ishioma Bridget , Onyekonwu Mike Obi
Published: August 2020

The identification and classification of lithofacies is key to understanding the heterogeneity of the reservoir. Traditional manual facies prediction using well log data are characterized by uncertainties and are often time consuming especially when working with large datasets. Machine learning provides a more efficient way of predicting facies when applied to large data. In this study we consider unsupervised learning approach: clustering and supervised learning approach: support vector machine for facies classification. Unsupervised learning was done using only raw and processed well logs parameters and the responses were grouped into various clusters based on similarities. Optimal number of clusters were selected from the elbow plot and dendogram. The supervised learning is done using well logs-raw and processed parameters. The targeted output was depofacies defined using core facies derived from core data. Both approaches showed good results with less uncertainty and bias when compared to already established facies defined from core data. The result from this process provides a more realistic input for generating facies models.
Well Abandonment and Wellsite Restoration: Case Studies of Well Sites Restored After Oil Production in Onshore Nigeria
Authors: Adebayo Adejoke , Ahmed Suleiman , Agbogu George , Ezenobi Eric , Akiba-eyo Effiowan
Published: August 2020

Oil and gas production process starts from exploration, to appraisal, to development, and finally to abandonment. Exploration is done on the prospective field to determine presence of hydrocarbon (HC) and if present, an appraisal of the extent and volume of the HC is done. If the quantity of HC is found to be enough, it is developed and produced and after production of the HC reserve, abandonment is done.

For the exploratory, appraisal and development processes, wells are drilled, and this drilling involves making holes thousands of feet into the sub soil and the installation of tubulars and other completion accessories to ensure that the hydrocarbon comes to surface with ease and in a safe manner.

Wells are abandoned either because it has produced its potential and cannot be used for production anymore, or due to some integrity issues that could only be prevented by abandonment. To abandon a well, the produced/open HC reservoirs are properly isolated to prevent flow into other HC reservoirs or water bearing sands. The installed tubulars and accessories are then retrieved to surface.

After abandonment, to further reduce the environmental impact of the oil development, the sites are recommended to be fully restored to the pre-development state as much as possible.

This paper details the technical abandonment activities carried out for five wells that have produced for several years in onshore Nigeria. The paper also explains the site restoration activities and shows the various well site restoration stages including the re-vegetation of some of the well sites.
A Scheme for Estimating the Magnitude of the Maximum Horizontal Stress for Geomechanical Studies
Authors: Nwonodi Roland , Dosunmu Adewale , Ubani Chikwendu , Ojanomare Choja
Published: August 2020

It is very challenging to obtain values for the horizontal stresses in the subsurface, particularly the maximum horizontal stress. This discourages well planning, drilling operations, drill cuttings reinjection and geomechanical studies in general. While it is important to obtain accurate values of the in-situ stresses, there are currently no easy ways to get the maximum horizontal stress ahead of drilling operation. Results from the theory of elasticity may be possible, but there can be more unknowns than the required stresses and the lateral strains are hardly known. Hence, this research seeks to find ways to accurately determine the maximum horizontal stress. To this end, a generalized 3D expression was obtained from the elastic theory of subsurface stresses. Randomized set of 5000 data for the polyaxial stresses, in the range of 0.55-1.0 Psi/ft, were generated using sophisticated computer applications and plotted in the MATLAB software in order to get the parameters in the equation. The data were sorted in the order typical of a normal stress regime and the result obtained showed consistency with known practice. Thus, in order to determine an accurate value for the maximum horizontal stress: first obtain the vertical stress from density log; use data from leak-off test to obtain the minimum horizontal stress; obtain the pore pressure within the interval using conventional method; then use the development in this study to get the maximum horizontal stress.
Integrated Hydrocarbon Maturation of Three Reservoirs X1, X2-E, X2-W in the KOCA Field, Niger-Delta
Authors: Iwegbu Chiedu , Dudun Anireju , Olu-Oseh Okasime , Njoku Kelechi
Published: August 2020

Subsurface uncertainties in reservoir characterization remains a challenge in decision making in the development phase of hydrocarbon maturation process due to geological complexity and limitations in reservoir data to provide sufficient understanding of the subsurface. This study focuses on identifying, managing, narrowing these uncertainties and generating reservoir realizations and optimum development concept consistent with available data. Hence, the objective of this study is to generate a technically feasible & economically viable development plan for X1, X2W and X2E reservoirs in KOCA field.

The methodology deployed on this study is a multi-disciplinary integrated approach in a parallel setting with early focus on uncertainty identification, quantification, management and iterations amongst the team. Sensitivity analysis was used to evaluate the respective impact of the identified uncertainties on in-place and recoverable volumes and realizations were constrained by the most impacting uncertain parameters to generate a low case, base case and high case valid realizations of the subsurface. Development concepts were selected to optimize recovery using the base case realization with preliminary economic evaluations used to determine concepts economic viability.

The result of this study identifies Structure, Net-to-Gross, and Permeability as the top three uncertainties with most impact on volumes. Deterministic low, base and high case GIIP volumes computed are 354Bscf, 681Bscf and 1.1Tscf, while recoveries were 261Bscf, 546Bscf and 913Bscf respectively. Deterministic low, base and high case STOIIP volumes computed are 0.4MMSTB, 1.5MMSTB and 3.4MMSTB, while recoveries were 0.1MMSTB, 0.2MMSTB, and 0.02MMSTB respectively. Optimum subsurface development concept is two vertical gas well, no horizontal well is needed to develop the thin (12ft) oil rim and finally quick look project economics revealed that the project would be economically viable even for the Low-Case outcome: NPV (10%) is $150M and VIR (10%) is 3.92.
Integrated Production Forecasting for Improved Business Planning and Hydrocarbon Asset Management: A Niger Delta Brown Asset Experience
Authors: Ohabuike Onyemaechi , Afoama Ebuka , Bakor Leziga , Onyeka Emeka , Egbe Thankgod
Published: August 2020

There is a continuous need to improve hydrocarbon recovery efficiency especially from a brown asset, with a view to extending the life of the asset with reasonable operating cost in order to deliver sustained profit to the business. This is made even more imperative due to the dwindling crude oil prices and an operating environment with ever increasing challenges especially in the area of security, asset integrity, frequent deferment due to export line vandalism and crude theft, and community disturbances. All these factors result in most companies operating within the Niger Delta environment and by extension the country at large not being able to create robust production forecasts to support their annual business plans. In the end, actual annual average crude production ends up much lower in most cases than the projected plan. The big question however is: How do we build robust forecasting models that can better predict our business outcomes in the Niger Delta?

This paper seeks to demonstrate the possibilities available within the Nigerian space, all driven and developed with indigenous capabilities, of how this problem was successfully solved for a major asset, operated by a leading indigenous Exploration and Production company through active collaboration with another leading indigenous Petroleum Engineering software solutions provider.
Tracking and Reduction of Geological Non-Productive Time – A Case Study of an Oil Field in Niger Delta Basin, Nigeria
Authors: Onyeji J. A , Ekun O. A , Asaolu A. O. , Mba A. P , Owoyemi A. O. , Nwachukwu A. P.
Published: August 2020

It is a well-established practice in the oil and gas industry to capture daily non-productive time (NPT) resulting from unscheduled events during drilling campaigns. Annually, the cost estimate of non-productive time (NPT) is about 31 percent of the total cost of drilling per well in the study area. Geologic Non-Productive Time (GNPT) caused by geological related subsurface events constitute major part of NPT. In most cases, GNPT is not usually tracked and or decoupled from NPT and this has made it difficult to focus efforts on with a view to proffering solutions to their occurrences. The objective of this study is to identify, measure, track and analyze underlying causes of GNPT in order to minimize or prevent financial losses and potential damages (tangible & intangible) associated with these events. The methodology used in this study includes integration of subsurface cuttings and geological features, formation evaluation challenges and observed drilling events to define twelve major subsurface events that were grouped into four GNPT categories. The categories are: (1) well flow, (2) lost circulation, (3) wellbore instability and (4) Subsurface evaluation. These events were tracked with the corresponding cost and rig time implications for wells drilled within the selected time frame. Fifty wells were drilled between 2015 to 2017 in our study area, and GNPT occurred in seventeen wells costing millions of dollars. From our analysis of the tracked GNPT over this period, the GNPT big hitters were found to be wellbore instability and lost circulation issues. The result of this study led to concerted efforts at reducing the GNPT in the drilling operations by focusing diligently on tackling the identified GNPT big hitters in 2017 through deployment of more accurate pore pressure, fracture gradient, wellbore stability modeling and most importantly, adopting effective communication strategies among the subsurface and drilling teams. This study aided in identifying, preventing and controlling the big hitters' events, thus reducing drilling incidents and overall well costs.
The Effects of Different Salt Types and Concentration on CO2 Injectivity During CO2 Sequestration in Deep Saline Aquifers
Authors: Edem Donatus , Abba Muhammad , Nourian Amir , Babaie Meisam , Mohammed Nuhu
Published: August 2020

Salting-out effect during CO2 storage in deep saline aquifers can have severe consequences during carbon capture and storage operations in terms of CO2 injectivity. The impact and physical mechanisms of salt precipitation in the vicinity of injection area is not fully clear. Core flooding experiments were conducted to investigate the effects of different brine-saturated sandstones during CO2 injection. The reported findings are directly relevant for CO2 sequestration operations as well as enhanced gas and oil recovery technologies (EGR, EOR). The characterisation and core analysis of the core samples to validate the petrophysical properties (Porosity, Permeability) of the core sample was carried out before core flooding using Helium Porosimetry. The brine solutions were prepared from different salts (NaCl, CaCl2, KCl, MgCl2), which represent the salt composition of a typical deep saline aquifers. The core samples were saturated with different brine salinities (5, 10, 15, 20, 25, wt.% Salt) and core flooding process was conducted at a simulated reservoir pressure of 1500 psig, temperature of 45°C, with a constant injection rate of 3 ml/min. The salting out effect was greater in MgCl2 and CaCl2 as compared to monovalent salt (NaCl and KCl). Porosity decreased by 0.5% to 7% while permeability was decreased by up to 50% in all the tested scenarios. CO2 solubility was evaluated in a pressure decay test, which in turn affects injectivity. The results from this study showed that the magnitude of CO2 injectivity impairment is dependent on both the concentration and type of salt. The findings provide basic understanding of the different salt concentration inducing salt precipitation during CO2 injection into core samples completely saturated with the formation brine. The insight gained in this study could be useful in designing an operating condition for CO2 sequestration in deep saline aquifers and minimising injectivity problems.
Crude Oil Price Risk Management: Should Nigeria Hedge Its Crude Oil Production?
Authors: Adegun Adedamola , Abiola Olalekan
Published: August 2020

The volatility of the crude oil market and the uncertainties imposed on oil companies and oil producing nations is well documented. For National Oil Companies (NOCs) vested with the responsibility of managing their country's oil and gas resources and providing revenue needed for much investments, the unpredictability of the crude oil market poses more challenges. In Nigeria, oil price fluctuations constraint national and sub-national budgets as oil benchmarks are typically optimistic. From 2015 – 2019, actual revenue accretion from crude oil sales compared to benchmark price and production have been as low as fifty percent (50%) of target.

To address the uncertainties and guarantee stable revenue, it's imperative for Nigeria to implement best practice in crude oil price risk management by considering the merits and demerits of available tools such as hedging. A pertinent question is if hedging (similar to Mexico) a credible, beneficial option for Nigeria? Would hedging have improved Nigeria's revenue if adopted in the last five (5) years? This paper attempts to provide answers by analysing various hedging options and studying the success and downsides of major sovereign hedging programs.

We further explored the empirical and normative dynamics that will accelerate or impede the adoption of hedging and suggested mitigating options. We find that considering the empirical factors alone, crude oil price risk management is a potentially viable option for Nigeria as benefits extend beyond direct revenue increase. Hedging will instil discipline, confidence and ultimately attract investments into the Nigerian oil sector. Our conclusions nonetheless recognise that the soft, qualitative factors around hedging if not well managed could be a drawback, impacting revenues.
Optimising Offshore Structures Decommissioning - A Multicriteria Decision Approach
Authors: Eke Emmanuel , Iyalla Ibiye , Andrawus Jesse , Prabhu Radhakrishna
Published: August 2020

Decommissioning activity is being delayed due to cash flow constraints in most companies, others are taking advantage of the low oil prices to expedite decommissioning activity as some associated cost becomes cheaper. Nevertheless, decommissioning is an emerging and growing market. There is a forecasted increase in global decommissioning projects from about $2.4 billion in 2015 to $13 billion per year by 2040, with an estimated 2000 offshore structures to be decommissioned between 2021 and 2040. These costs are very high considering decommissioning is an activity that does not necessarily bring in an income to producing companies. Thus, companies are seeking ways to optimize the process of decommissioning so as to reduce overall cost.

This work identifies and evaluates the various decommissioning options and criteria for decision making and proposes a multicriteria decision making approach that will optimise decommissioning process and efficiency savings.
Development of a Modified Weymouth Equation for Large Diameter Pipelines
Authors: Oladipo Akintunde , Nwankwo Princess
Published: August 2020

Flow equations are necessary for the estimation of flow rate in pipelines. Several flow equations exist and so do conventions for their application. Their range of applicability are delineated in literature such as D. W. Schroeder, Jr. and GL Noble Denton (2010). These works record the limited range of applicability of the Weymouth Equation compared to other existing flow equations. This failing of the Weymouth Equation is most prominent in large diameter pipelines. Fully turbulent flow predominates in large diameter pipelines like trunk lines and the use of Weymouth Equation for calculation of flow rate in such scenarios results in significant discrepancies. This work extends the range of applicability of the Weymouth to fully turbulent flow regimes in large diameter pipelines. In particular, the Weymouth friction factor is corrected by introducing a term accounting for internal pipe roughness.

Friction factors for different flow scenarios were calculated and plotted against the Reynolds Number and the Flow Rate to reveal the transition to fully turbulent flow regime. Python programming language was used to compute a table of friction data using both the Colebrook-White Equation and the Weymouth Friction Factor equation. A correction factor was introduced into the Weymouth friction factor that takes into consideration the variation of pipe roughness. Further, the new friction factor relationship was used to modify the existing Weymouth equation.

The Modified Weymouth Equation obtained predicted well for fully turbulent flow scenarios. Compared against the Weymouth Equation, it maintained an appreciable efficiency as pipe roughness was varied from standard values obtainable with new pipelines.

This study achieved its set objectives of improving the efficiency of the Weymouth Equation for large diameter pipelines. It will find application in the accurate estimation of flow rate as technologies evolve for non-intrusive determination of internal pipe roughness.
An Overview of Microbial Enhanced Oil Recovery in Nigeria
Authors: Anuka Agnes , Falode Olugbenga , Ogunshe Adenike , Udie Celestine
Published: August 2020

The use of microbial metabolites by interfacial tension reduction and wettability alteration mechanisms, for improved oil recovery from oil reservoirs, especially in mature oil fields have always been advocated for as a cheaper and environmentally-safe method of increasing oil production. Although microbial enhanced oil recovery (MEOR) in some advanced nations have come close to commercial applications, Nigeria is yet to venture into the microbial enhancement of oil recovery.

Nigeria as a nation has had its fair share of the global dilemma of decreased oil production caused by unrecovered oil in oil reserves, resulting in adverse effects on its economy energy status. Uncertainties on the efficiency of MEOR in practical reservoirs, failure of petroleum engineers and scientists to form multidisciplinary teams, and lack of adequate understanding of MEOR processes are some factors that have slowed down the process of adopting MEOR as an alternative to other enhanced oil recovery methods in Nigeria. Other significant factors include, lack of appropriate microbial mechanisms for the success of MEOR applications; various in situ and ex situ laboratory and field trials experiments on effectiveness of high-strength biosurfactants, in microbial enhanced oil recovery, best interfacial tension reduction and wettability alteration mechanisms, novel sets of core flooding tests, with potential indigenous and control microbial consortium, for optimal oil recovery efficiency; adsorption of microbial cells and biofilm formation for inductive MEOR, towards wettability alteration of reservoir rock for production of neutrally wet condition, for the improvement of oil recovery efficiency; modified advantageous quorum-sensing and behavioural diversity of potential MEOR-applicable microbes, as well as, genetic modification of selected safe and environmental-friendly candidates.

In addition to economic, health and environmental issues that still linger, and call for urgent attention, a general overview of microbial enhanced oil recovery in Nigeria comprising of the mechanisms of oil recovery by MEOR, factors hindering its implementation in Nigeria and the need for MEOR laboratory and field trials to be performed in order to determine the viability of the process in Nigeria is pertinent in order to provide a lasting solution to decreasing oil production.
Effect of low-dose exogenous surfactant on infants with acute respiratory distress syndrome after cardiac surgery: A retrospective analysis
Authors: Zhang Rongyuan , Wang Xu , Li Shoujun , Yan Jun
Published: August 2020

Background: Acute respiratory distress syndrome (ARDS) in infants undergoing cardiac surgery is associated with significant mortality and prolonged ventilation; surfactant administration may be a useful therapy. The purpose of this study was to evaluate the effect of low-dose exogenous surfactant therapy on infants suffering ARDS after cardiac surgery.

Methods: We conducted a case-control study of infants diagnosed with moderate-to-severe ARDS (PaO 2 /FiO 2 < 150) after cardiac surgery. A case was defined as a patient that received surfactant and standard therapy, while a control was defined as a patient that underwent standard therapy. The primary endpoint was the improvement in oxygenation index (OI) after 24-hour of surfactant treatment; and secondary endpoints were the ventilator time and PICU time.

Results: Twenty-two infants treated with surfactant were matched with 22 controls. Early low-dose (20mg/kg) surfactant treatment was associated with improved outcomes. After surfactant administration for 24-hour, the surfactant group was much better compared with the control group at the 24-hour in OI (difference in average change from baseline, -6.7 [95% CI, -9.3 to -4.1]) ( P < 0.01) and ventilation index (VI, mean difference, -11.9 [95% CI, -18.1 to -5.7]) ( P < 0.01). Ventilation time and PICU time were significantly shorter in the surfactant group compared with the control group (133.6h±27.2 vs 218.4h±28.7, P < 0.01 ; 10.7d±5.1 vs 17.5d±6.8, P < 0.01). Infants in the surfactant group under 3 months benefit more from OI and VI than the infants over 3 months in a preliminary exploratory analysis.

Conclusions: In infants with moderate-to-severe ARDS after cardiac surgery, early low-dose exogenous surfactant treatment could prominently improve oxygenation and reduce mechanical ventilation time and PICU time. Infants younger than 3 months may get more benefit of oxygenation than the older ones. Randomized controlled trials are needed to explore the effect of surfactant to ARDS of cardiac surgical infants.
Predictors of infant-survival practices among mothers attending paediatric clinics in Ijebu-Ode, Ogun State, Nigeria
Authors: Sokefun Eniolufolake Elizabeth , Atulomah Nnodimele Onuigbo
Published: August 2020

Background

Despite concerted global efforts towards achieving infant-survival, infant mortality lingers as a problem in developing countries. Environmental and personal-level factors are assumed to account for this situation. This study was undertaken to provide better understanding of the dynamics of predictors of infant-survival practices among mothers with infants attending paediatric clinics.

Methods

A cross-sectional survey design was adopted. Data was collected from 386 nursing mothers selected by convenience sampling. Interviewer-administered questionnaires were used for data collection. The questionnaire consisted of 38-items including demographic information of respondents, health-literacy counsels received during antenatal care, social-support from significant others, and self-efficacy to carry-out infant-survival instructions. Responses were transformed into rating scales for each variable and data analysis was conducted by linear regression analysis with test of hypotheses at 5% level of significance.

Results

The mean age of respondents was 29.8 ± 5.8 years. Majority (81.6%) were married. Yorubas (83.90%) were predominant. Participants had mean scores of 10.50±3.83, 10.56±3.70 and 16.61±4.56 respectively computed for levels of health-literacy, social-support, and self-efficacy. The dependent variable measured level of infant-survival practices and respondents scored 16.53±4.71. The study found a significant association among variables. Self-efficacy was the major predictor variable of self-reported infant-survival practices (R=0.466; R 2 =0.217; P˂0.05).

Conclusion

We conclude that participants had average levels of health-literacy, social-support, self-efficacy, and infant-survival practices. Healthcare providers should make efforts to empower pregnant women on activities essential for infant-survival. Family members of nursing mothers should as well be knowledgeable about the advantages of supporting them.
Substances use and its association with sociodemographic, family and environment-related factors among technical and vocational education and training College students in Ataye, Ethiopia, 2019.
Authors: wubetu abate dargie , Getachew Sintayehu , Negash Wassie
Published: August 2020

Background: Legal substances use is prevalent in Ethiopia. Substance use can have several health problems that are potentially harmful in educational performance, social issues, psychological and physical wellbeing. This study aimed to know prevalence of lifetime and last month substances use and its associated factors among technical and vocational education and training College students in Ataye town. Methods: An institution based cross-sectional study conducted from 1 March to last May 2019. Participants selected by using simple random sampling technique. Data collected by using a structured and pretested self-administered questionnaire. Data collected by five trained diploma nurses with close supervision. Odds ratio with their 95% confidence interval, and p value less than 0.05 used to declare the statistical significance of associated factors. Results: Four hundred eighty three individuals participated in the study, which was a response rate of 94%. The prevalence of lifetime legal substances use was 32.5% (95% CI: 28.2, 36.5). The prevalence of last month's legal substances use was 21.9% (95% CI= 18.2, 25.5). Among lifetime legal substance users, the majority (25.5%) chewed khat. The others, (19.5%) drunk alcohol, and, 15.3% smoked cigarette in lifetime. Lifetime cannabis and cocaine users were 2.5%, and 7.2% respectively. Among last month's legal substance users, (21.9%) chewed khat followed by alcohol drinking (16.6%), and cigarette smoking (15.3%). In the last month, 1.2% and 3.3% of students used cannabis and cocaine respectively. Multivariate logistic regression showed that, being male, 4having divorced family, living greater than twenty years in the town, having substance user family member, having intimate friend substance user, and easily availability of substances were independent predictors of lifetime legal substances use. Conclusions: The prevalence of last month and lifetime legal substance use at Ataye Technical and Vocational Education and Training (TVET) college students were analogous with most studies done in Ethiopia. It is advisable if furthers emphasis is given for TVET students with the predictor variables.
Echography analysis of musculoskeletal, heart and liver alterations associated with endothelial dysfunction in obese rats
Authors: Coria Alejandra Martínez , Estrada-Cruz Norma Angélica , Ordoñez María Inés Pérez , Montes-Cortes Daniel H. , Manuel-Apolinar Leticia
Published: August 2020

Background: Modern imaging plays a central role in the care of obese patients, and there is an integral focus on its use and accessibility in individuals who have alterations of various in various organs. The objective in this study was to perform an echographic analysis of musculoskeletal system disorders, endothelial dysfunction and the left ventricle (LV) in obese rats.

Methods: Sprague Dawley rats (250±5g) were obtained and divided into two groups: the control (C) group was fed with a standard diet, and the obese (Ob) group was fed hyper caloric diet with a high fructose-fat content for 4 months. Body weight, cholesterol, triglycerides, glucose, inflammatory cytokines and adhesion molecules (ICAM-1, VCAM-1) were measured. Additionally, two-dimensional echocardiography, abdominal ultrasound and musculoskeletal system studies were performed in the lower extremities.

Results: The body weight in the Ob group was increased compared to that in the control group, (p<0.001); in addition, increased glucose, cholesterol and triglyceride concentrations (p<0.05) as well as increased levels of the adhesion molecules ICAM-1 and, VCAM-1 (p<0.01) were found in the Ob group vs the C group. On ultrasound, 75% of the Ob group presented fatty liver and distal joint abnormalities.

Conclusion: Obese rats exhibit endothelial dysfunction and musculoskeletal changes, also, fatty liver and articular cysts in the posterior region of the distal lower- extremity joints.
Socio-demographic and environmental factors of diarrhea among under-five children in India
Authors: Paul Pintu
Published: August 2020

Background: Globally, diarrhea is the second leading cause of death in children under five years of age and is a major public health problem. Despite several health care initiatives taken by the government, a large proportion of under-five children still experience diarrheal diseases which cause high childhood mortality in India. This study aims to examine the socio-demographic and environmental factors of diarrhea in children under five years old in India. Methods: A cross-sectional study was designed using the recent round of the National Family Health Survey (NFHS), conducted in 2015–16. A total of 247,743 living children below five years of age were included in the analysis. Bivariate and multivariate logistic regression models were carried out to assess the factors associated with childhood diarrheal disease. Results: In India, about 9% of under-five children experience diarrheal disease in the past two weeks. Children living in rural areas (Adjusted odds ratio [aOR]: 1.05; 95% CI: 1.01, 1.09), belonged to scheduled tribe (aOR: 0.83; 95% CI: 0.79, 0.89) and other castes (aOR: 0.92; 95% CI: 0.88, 0.97), Muslim children (aOR: 1.18; 95% CI: 1.13, 1.24), and children resided in the central (aOR: 1.61; 95% CI: 1.52, 1.70) and west (aOR: 1.08; 95% CI: 1.01, 1.15) regions were significantly associated with higher likelihood of diarrhea in the past two weeks. Concerning environmental factors, child stool disposal (aOR: 1.06; 95% CI: 0.98, 1.09), floor materials (aOR: 1.08; 95% CI: 1.03, 1.12) and roof materials (aOR: 1.08; 95% CI: 1.04, 1.13) of the household were found to be significant factors of childhood diarrhea occurrence. Conclusions: Diarrhea is common among rural, scheduled caste, Muslim and poor families’ children. Regarding environmental factors, stool disposal practices in the household, main floor and roof materials of the household unit are risk factors of diarrhea. Targeted approach should be initiated to mitigate the problem of poor health status of children by providing adequate health care. The policy-makers and stakeholders should address adverse environmental conditions by the provision of latrine and improved housing facilities.
Classification and morphology of middle mesial canals of mandibular first molars in a southern Chinese subpopulation: a cone-beam computed tomographic study
Authors: Yang Yeqing , Wu Buling , Zeng Junkai , Chen Ming
Published: August 2020

Background: Cone-beam computed tomography (CBCT) was employed to study the morphology and curvature of middle mesial canals (MMCs) of mandibular first molars (MFMs).Methods: CBCT scanning was performed on MFMs of 1100 patients. Patients' images that met the inclusion criteria were divided into group A (<40 years old) and group B (≥40 years old) for further study. The images were used to study the incidence of MMCs at different ages, measure the curvature of MMCs in the mesiodistal and buccolingual directions using the Schneider method, and observe the anatomical morphology of the mesial root canal system.Results: In 875 patients, 1750 MFM images met the inclusion criteria. Among these cases, 158 MFMs contained an MMC, yielding an incidence rate of 9.03%. The incidence rate of MMCs was 11.22% in group A and 6.61% in group B, and this difference was statistically significant (P<0.05). The curvature in the mesiodistal direction was 29.39±8.53º in group A and 26.06±8.50º in group B, and this difference was also significant (P<0.05). The curved regions in groups A and B were often located in the middle 1/3 of canal. No significant difference in the distance between MMC orifices and mesiobuccal canal orifices or mesiolingual canal orifices was noted (P>0.05). The most common mesial root canal morphological type was type II (3-2) (53.80%). Conclusion: The incidence of MMCs in MFMs declined as age increased. The canal systems of MMCs were varied and complex, mainly exhibiting an obvious mesiodistal curve. CBCT is an outstanding method to help guide root canal therapy.
Sperm miRNAs— potential mediators of bull age and early embryo development
Authors: Wu Chongyang , Blondin Patrick , Vigneault Christian , Labrecqu Rémi , Sirard Marc-André
Published: August 2020

Background: Sperm miRNAs were reported to regulate spermatogenesis and early embryonic development in some mammals including bovine. The dairy cattle breeding industry now tends to collect semen from younger bulls under high selection pressure at a time when semen quality may be suboptimal compared to adult bulls. Whether the patterns of spermatic miRNAs are affected by paternal age and/or impact early embryogenesis is not clear. Hence, we generated small non-coding RNA libraries of sperm collected from same bulls at 10, 12, and 16 months of age, using 16 months as control for differential expression and functional analysis. Results: We firstly excluded all miRNAs present in measurable quantity in oocytes according to the literature. Of the remaining miRNAs, ten sperm-borne miRNAs were significantly differentially expressed in younger bulls (four in the 10 vs 16 months contrast and six in the 12 vs 16 months contrast). Targets of miRNAs were identified and compared to the transcriptomic database of two-cell embryos, to genes related to two-cell competence, and to the transcriptomic database of blastocysts. Ingenuity pathway analysis of the targets of these miRNAs suggested potential influence on the developmental competence of two-cell embryos and on metabolism and protein synthesis in blastocysts. Conclusions: The results showed that miRNA patterns in sperm are affected by the age of the bull and may mediate the effects of paternal age on early embryonic development.
Differential diagnosis of coronavirus disease 2019 from community acquired - pneumonia by CT scan and follow-up
Authors: Liu Kai-Cai , Xu Ping , Lv Wei-Fu , Chen Lei , Qiu Xiao-hui , Yao Jin-Long , Gu Jin-Feng , Hu Bo , Wei Wei
Published: August 2020

Objective: Coronavirus disease 2019 (COVID-19) is currently the most serious infectious disease in the world. An accurate diagnosis of this disease in the clinic is very important. This study aims to improve the differential ability of computed tomography (CT) to diagnose COVID-19 and other community-acquired pneumonias (CAPs) and evaluate the short-term prognosis of these patients. Methods: The clinical and imaging data of 165 COVID-19 and 118 CAP patients diagnosed in seven hospitals in Anhui Province, China from January 21 to February 28, 2020 were retrospectively analysed. The CT manifestations of the two groups were recorded and compared. A correlation analysis was used to examine the relationship between COVID-19 and age, size of lung lesions, number of involved lobes, and CT findings of patients. The factors that were helpful in diagnosing the two groups of patients were identified based on specificity and sensitivity. Results : The typical CT findings of COVID-19 are simple ground-glass opacities (GGO), GGO with consolidation or grid-like changes. The sensitivity and specificity of the combination of age, white blood cell count, and ground-glass opacity in the diagnosis of COVID-19 were 92.7% and 66.1%, respectively. Pulmonary consolidation, fibrous cords, and bronchial wall thickening were used as indicators to exclude COVID-19. The sensitivity and specificity of the combination of these findings were 78.0% and 63.6%, respectively. The follow-up results showed that 67.8% (112/165) of COVID-19 patients had abnormal changes in their lung parameters, and the severity of the pulmonary sequelae of patients over 60 years of age worsened with age. Conclusions : Age, white blood cell count and ground-glass opacity have high accuracy in the early diagnosis of COVID-19 and the differential diagnosis from CAP. Patients aged over 60 years with COVID-19 have a poor prognosis. This result provides certain significant guidance for the diagnosis and treatment of new coronavirus pneumonia.
The social construction of the social epigenome and the larger biological context
Authors: deichmann ute
Published: August 2020

Epigenetics researchers in developmental, cell, and molecular biology greatly diverge in their understanding and definitions of epigenetics. In contrast, social epigeneticists, e.g. sociologists, scholars of STS, and behavioural scientists, share a focus and definition of epigenetics that is environmentally-caused and trans-generationally inherited. This article demonstrates that this emphasis on the environment and on so-called Lamarckian inheritance, in addition to other factors, reflects an interdisciplinary power struggle with genetics, in which epigenetics appears to grant the social sciences a higher epistemic status. Social scientists' understanding of epigenetics thus appears in part to be socially constructed, i.e. the result of extra-scientific factors, such as social processes and the self-interest of the discipline. This article argues that social epigeneticists make far-reaching claims by selecting elements from research labelled epigenetics in biology while ignoring widely confirmed scientific facts in genetics and cell biology, such as the dependence of epigenetic marks on DNA sequence specific events, or the lack of evidence for the lasting influence of the environment on epigenetic marks or the epigenome. Moreover, they treat as a given crucial questions that are far from resolved, such as what role, if any, DNA methylation plays in the complex biochemical system of regulating gene activity. The article also points out incorrect perceptions and media hypes among biological epigeneticists and calls attention to an apparent bias among scientific journals that prefer papers that promote transgenerational epigenetic inheritance over articles that critique it. The article concludes that while research labelled epigenetics contributes significantly to our knowledge about chromatin and the genome, it does not, as is often claimed, rehabilitate Lamarck or overthrow the fundamental biological principles of gene regulation, which are based on specific regulatory sequences of the genome.
Effects of calcitriol on oxidative burst, phagocytic function, and leukocyte cytokine production in shelter dogs
Authors: Jaffey Jared , Bessette Mariah , Tao Zenan , Bradley-Siemens Nancy , Thompson Melissa
Published: August 2020

Background

The active metabolite of vitamin D, calcitriol, has been shown across many different species to augment innate immune responses and dampen aberrant proinflammatory cytokine production. Community acquired infections are common in shelters and consume limited shelter resources, impact adoption rates, and can result in unnecessary euthanasia. Prophylactic oral vitamin D supplementation decreases the incidence and severity of upper and lower respiratory tract infections in humans. Before a clinical trial investigating the clinical benefit of oral vitamin D supplementation in shelter dogs can be pursued, an in vitro study evaluating the immunomodulatory effects of calcitriol in blood from shelter dogs is warranted. Therefore, the objective of this study was to determine if incubation of whole blood obtained from apparently healthy dogs housed in a shelter for ≥ 7 days with calcitriol would alter granulocyte/monocyte (GM) oxidative burst and phagocytic function as well as pathogen-associated molecular pattern (PAMP)-stimulated leukocyte production of tumor necrosis factor (TNF)-α, and interleukin (IL)-6, and IL-10.

Results

Ten dogs housed in a shelter for ≥ 7 days were enrolled in a prospective cohort study. Whole blood from these dogs was incubated with calcitriol (10 -7 M) or diluent (control) for 24 h. Subsequent to this incubation phagocytosis of opsonized- Escherichia coli ( E. coli ) and E. coli -induced oxidative burst were evaluated via flow cytometry. In addition, leukocyte production of TNF-α, IL-6, and IL-10 were measured using a canine-specific multiplex assay. Calcitriol significantly decreased leukocyte TNF-α production ( p = 0.009) and increased IL-10 production ( p = 0.002). Tumor necrosis factor-α-to-IL-10 ratio was significantly decreased with calcitriol ( p = 0.017), while IL-6 production as well as GM oxidative burst and phagocytic function were not significantly affected.

Conclusions

These data indicate that calcitriol attenuates proinflammatory immune responses without affecting GM oxidative burst or phagocytic function in vitro in whole blood obtained from apparently healthy shelter dogs.
Marker assisted development and characterization of herbicide tolerant Near Isogenic Lines of a mega Basmati rice variety, “Pusa Basmati 1121”
Authors: Grover Nitasha , Kumar Aruna , Yadav Ashutosh Kumar , S. Gopala Krishnan , Ellur Ranjith Kumar , Bhowmick Prolay Kumar , Vinod K.K. , Bollinedi Haritha , Nagarajan M. , Viswanthan C. , Sevanthi Amitha Mithra V. , Singh Nagendra Kumar , Mohapatra Trilochan , Singh Ashok Kumar
Published: August 2020

Background

Direct-seeded rice (DSR) is a potential technology for sustainable rice farming as it saves water and labor. However, higher incidence of weed under DSR limits productivity. Therefore, there is a need to develop herbicide tolerant (HT) rice varieties.

Results

We used marker assisted backcross breeding (MABB) to transfer a mutant allele of Acetohydroxy acid synthase ( AHAS ) gene, which confers tolerance to imidazolinone group of herbicides from the donor parent (DP) “Robin” into the genetic background of an elite popular Basmati rice variety Pusa Basmati 1121 (PB 1121). Foreground selection was done using the AHAS gene linked Simple Sequence Repeat (SSR) marker RM6844 and background selection was performed using 112 genome-wide SSR markers polymorphic between PB 1121 and Robin. Phenotypic selection for agronomic, Basmati grain and cooking quality traits in each generation was carried out to improve the recovery of recurrent parent phenome (RPP). Finally, a set of 12 BC 4 F 4 near isogenic lines (NILs), with recurrent parent genome (RPG) recovery ranging from 98.66 to 99.55% were developed and evaluated. PB 1121-HT NILs namely 1979-14-7-33-99-10, 1979-14-7-33-99-15 and 1979-14-7-33-99-66 were found superior to PB 1121 in yield with comparable grain and cooking quality traits and herbicide tolerance similar to Robin.

Conclusion

Overall, the present study reports successful development of HT NILs in the genetic background of popular Basmati rice variety PB 1121 by introgression of mutated AHAS allele. This is the first report on the development of HT Basmati rice. Superior NILs are being evaluated in the national Basmati trials, the release of which is likely to provide a viable option for the adoption of DSR technology in Basmati rice cultivation.