bluuebunny/crossref_metadata_2025 huggingface dataset:
Successful Implementation of Blast Joint Perforation Technology in a Dual String Completion
Authors: Ofia Ifeanyichukwu , Briggs Esther , Longe Victor , Iyengumwena Ricky , Wong Dominic
Published: August 2021

The results of computer simulations and laboratory tests have been applied at Porth field in Nigeria to achieve a successful perforation through a blast joint to access hydrocarbon behind pipe.

Accessing hydrocarbons behind pipe in multizone completions can be difficult. The options are; an expensive rig-based workover or a cost-effective, rigless, through-tubing perforation. For a rigless through-tubing option, the detonated perforation charges must pass through a blast joint, the casing and the cement and then into the target reservoir. The major concern is usually whether there will be enough penetration {Burky 2018} into the target reservoir interval, given the layers of material resistance that the charges will have to overcome, starting at the blast joint. The Blast joint has a higher wall thickness and a larger outer diameter than that of the conventional tubing string to mitigate against erosion from producing the target interval behind pipe. The goal in perforation operations is achieving the maximum production while reducing perforation damage. {Jackson 2016}.

Computer simulations and laboratory tests for a well at Porth field in Nigeria were carried out to determine the potential for successful perforation through a blast joint to access hydrocarbon behind pipe. Coupon tests using different gun sizes and charges where simulated and tested to ascertain the most effective option to achieve the desired reservoir penetration. Both computer simulations and laboratory test results showed that a reasonable depth of penetration into the target reservoir interval was possible to achieve. The perforation job using a 1.56-in., six-shots-per-foot (6 spf), 60° phasing gun was successfully carried out and the well has been tested to a potential of 780bbl/d at a tubing head pressure of 943psi and choke size 20/64th.

This success lays the foundation for going after other similar opportunities locked in behind-pipe previously thought inaccessible owing to the presence of a blast joint across the target interval. Associated rig costs for a workover of up to $10 million can be saved on each opportunity using this approach.
Hydrocarbon of the Future: Sustainability, Energy Transition and Developing Nations
Authors: Ifalade Oluwajuwon , Obode Elizabeth , Chineke Joseph
Published: August 2021

The population of Africa is estimated to be about 1.5 billion, 25% of world population but the continent accounts for only 3.2% of global electricity generation (2.2% coming from South Africa, Egypt, Algeria and Morocco). This translates to the lowest per capita energy of any continent. The rapidly growing population in Africa will inevitably result in the emergence of more African cities and this underscores a need to urgently address the energy poverty concerns presented.

The global energy landscape is changing, and Africa finds herself at a vantage point in the complex interplay between energy, development, climate change and sustainability. The need to provide an answer to these concerns is further highlighted by the effects of globalization and climate change.

The onus rests on African countries to find a cross-functional solution; one which answers simultaneously to socio-economic and environmental challenges. This involves driving growth in energy supply and hence industrialization via the adoption of a balanced mix that harnesses all energy potential and integrated utilization possibilities.

Projected increase in energy demands coupled with emission allowances present a unique opportunity for these countries to put in place plans and infrastructure congruent with the future energy landscape. In contrast to the narrative where African energy is driven majorly by renewables, the continent must first maximize the enormous fossil fuel potentials domiciled in large gas reserves in some of her countries to create an economy that can support a sustainable energy future.

Natural gas is expected to play a vital role in the transition to a more environment friendly future of energy, especially in developing countries. This paper aims to present the prospects and challenges of the use of natural gas as a driver of sustainability and energy transition in the developing nations. Nigeria and the Nigerian Gas Master Plan will be taken as a Case Study.
Characteristics of Dimensionless Pressure Gradients and Derivatives of Horizontal and Vertical Wells Completed within Inclined Sealing Faults
Authors: Ogbamikhumi A V , Adewole E S
Published: August 2021

Dimensionless pressure gradients and dimensionless pressure derivatives characteristics are studied for horizontal and vertical wells completed within a pair of no-flow boundaries inclined at a general angle ‘θ’. Infinite-acting flow solution of each well is utilized. Image distances as a result of the inclinations are considered. The superposition principle is further utilized to calculate total pressure drop due to flow from both object and image wells. Characteristic dimensionless flow pressure gradients and pressure derivatives for the wells are finally determined.

The number of images formed due to the inclination and dimensionless well design affect the dimensionless pressure gradients and their derivatives. For n images, shortly after very early time for each inclination, dimensionless pressure gradients of 1.151(N+1)/LD for the horizontal well and 1.151(N+1) for vertical well are observed. Dimensionless pressure derivative of (N+1)/2LD are observed for central and off-centered horizontal well locations, and (N+1)/2 for vertical well are observed.

Central well locations do not affect horizontal well productivity for all the inclinations. The magnitudes of dimensionless pressure drop and dimensionless pressure derivatives are maximum at the farthest image distances, and are unaffected by well stand-off for the horizontal well.
Alternative Energy Values in Natural Gasfractionation
Authors: Udie Celestine A. , Anuka Agnes A. , Ana Ekpenyong A.
Published: August 2021

Global energy crisis has been on the increase due to increase on energy demand driven by population growth. In attempting to address the global energy crisis, this work uses the alternative resources to diversify the conventional energy sources in order to supplement the available energy generating sources. Energy resources are being evaluated to supplement the conventional energy sources thereby boosting the total energy generation in a nation. Technical and economic models are developed and used to evaluate the energy values in natural gas fractionation. Natural gas fractions evaluated include liquefied natural gas (LNG), liquefied petroleum gas (LPG) and condensate (liquid fuel). Collated field data are inputted into the developed economic models to estimate feasible technical and economic values in each of the gas fractions. The technical and economic analysis revealed that bulk natural gas contains 85.76% liquefied natural gas, 11.61% liquefied petroleum gas and 2.28% condensate (liquid). The result also revealed that natural gas fractionation improves its economic and energy values. With this, it is clear that the improvement in natural gas energy sources has the potency to supplement, hydro-electric power source, coal power source, oil and/or diesel fuel power sources.
Laboratory-Scale Investigation of the Utilisation of Multiple Flat-Fan Nozzles in Descaling Petroleum Production Tubing
Authors: Yar'Adua Kabir Hasan , John Idoko Job , Abbas Abubakar Jibril , Suleiman Salihu M. , Ahmadu Abdullahi A. , Kabir Aisha
Published: August 2021

Despite the recent wide embrace of mechanical descaling approaches for cleaning scales in petroleum production tubings and similar conduits with the use of high-pressure (HP) water jets, the process is still associated with downhole backpressure and well integrity challenges. While the introduction of sterling beads to replace sand particles in the water recorded high successes in maintaining well completion integrity after scale removal in some recent applications of this technique, it is, unfortunately, still not without questions of environmental degradation. Furthermore, the single nozzle, solids-free, aerated jetting descaling technique – recently published widely – is categorized with low scale surface area of contact, low descaling efficiency and subsequent high descaling rig time. The modifications to mechanical descaling techniques proposed in this work involve the use of three high-pressure flat fan nozzles of varying nozzles arrangements, standoff distances and injection pressures to remove soft scale deposits in oil and gas production tubings and similar circular conduits. This experiment provides further insights into the removal of paraffin scales of various shapes at different descaling conditions of injection pressures, stand-off distances and nozzle arrangements with the use of freshwater. The results obtained from this study also show consistency with findings from earlier works on the same subject.
A Suitable Model for Assessing the Integrity of Subsea Control Modules SCMs for Re-Use after Decommissioning
Authors: Root Eric , Andrawus Jesse , Iyalla Ibiye
Published: August 2021

This paper proposes a model for assessing Subsea Control Module (SCM) integrity for re-use after decommissioning. The SCM is one of the most failure-prone components in subsea oil and gas developments, and although a relatively inexpensive component in a Subsea Production System (SPS), the failure of an SCM can require production to be ceased, significantly impacting project economics. The re-use of decommissioned SCMs could improve the economics of subsea oil and gas projects by reducing design and manufacturing lead times, improving production availability, and enabling the economic exploitation of both marginal and mature fields. Insights gained through relevant literature, industry standards, and subsea industry experts led to the development of the Integrity Assessment Model for Decommissioned Subsea Control Modules proposed in this paper. The model is based on an Integrity Assessment process as well as a Risk-Based Compatibility Assessment. Discussions include a background of the SCM and common failures, the economics of SCM re-use, and Applications for the re-use of SCMs. The Integrity Assessment Model is described in detail, as well as the benefits and limitations. Areas of future research in support of subsea equipment re-use are identified, including improvements to reliability databases for subsea equipment, and the creation of a quantitative metric describing subsea equipment integrity.
Optimisation of Offshore Structures Decommissioning – Cost Considerations
Authors: Eke Emmanuel , Iyalla Ibiye , Andrawus Jesse , Prabhu Radhakrishna
Published: August 2021

The petroleum industry is currently being faced with a growing number of ageing offshore platforms that are no longer in use and require to be decommissioned. Offshore decommissioning is a complex venture, and such projects are expected to cost the industry billions of dollars in the next two decades. Early knowledge of decommissioning cost is important to platform owners who bear the asset retirement obligation. However, obtaining the cost estimate for decommissioning an offshore platform is a challenging task that requires extensive structural and economic studies. This is further complicated by the existence of several decommissioning options such as complete and partial removal. In this paper, project costs for decommissioning 23 offshore platforms under three different scenarios are estimated using information from a publicly available source which only specified the costs of completely removing the platforms. A novel mathematical model for predicting the decommissioning cost for a platform based on its features is developed. The development included curve-fitting with the aid of generalised reduced gradient tool in Excel® Solver and a training dataset. The developed model predicted, with a very high degree of accuracy, platform decommissioning costs for four (4) different options under the Pacific Outer Continental Shelf conditions. Model performance was evaluated by calculating the Mean Absolute Percentage Error of predictions using a test dataset. This yielded a value of about 6%, implying a 94% chance of correctly predicting decommissioning cost.
Challenges of Developing Marginal Fields in the Current Climate of Oil and Gas Industry
Authors: Danmadami Amina , Iyalla Ibiye , Oluyemi Gbenga , Andrawus Jesse
Published: August 2021

Marginal field development has gained relevance in oil producing countries because of the huge potential economic benefits it offers. The Federal Government of Nigeria commenced a Marginal Fields program in 2001 as part of her policy to improve the nation’s strategic oil and gas reserves and promote indigenous participation in the upstream sector. Twenty years after the award of marginal fields to indigenous companies to develop, 50% have developed and in production, 13% have made some progress with their acquisition while 37% remain undeveloped. The poor performance of the marginal field operators is due to certain challenges which have impeded their progress.

A review of challenges of developing marginal fields in the current industry climate was conducted on marginal fields in Nigeria to identify keys issues. These were identified as: funding, technical, and public policy. Considering the complex, competitive and dynamic environment in which these oil and gas companies operate, with competition from renewables, pressure to reduce carbon footprint, low oil price and investors expectation of a good return, companies must maintain tight financial plan, minimize emissions from their operations and focus on efficiency through innovation.

The study identifies the need for a decision-making approach that takes into consideration multi criteria such as cost, regulation, quality, technology, security, stakeholders, safety and environment, as important criteria based on which to evaluate the selection of appropriate development option for marginal fields.
Renewable and Unconventional Energies
Authors: Aniebo Igolo Nonye
Published: August 2021

Renewable and unconventional energies have finally moved from the realm of ideas to fact. They, as was expected and feared, have forced deep changes in world economies. Fortunately, they have, at the same time, begun to fulfill an aspect of the dream that made them an alluring idea in the first place- help humanity fight climate change. For decades, large scale exploitation of energy has been the preserve of industrialized nations. It is therefore understandable that they would lead the push for the practicalization of renewables and unconventional energies. Since the nations occupy less than a third of the world, their diminished carbon footprint will not be enough to reverse the effects of climate change. The objective of this research is to posit that just as these nations initiated and were mainly responsible for the excessive and unregulated use of fossil fuels all over the world, they should also try to do the same for renewables if they want to save humanity from the devastating effects of climate change. Nigeria, like most countries in Africa, is a case in point. Her fossil fuels, coal, oil, and gas were brought on stream in the twentieth century to satisfy foreign demands. Now that these demands have found other sources, a chaotic operation has been left for the locals to vandalize or operate, further creating a disastrous situation that will speed up climate change. What is true for Nigeria is equally true for more than 50 other foreign created/controlled countries of Africa, the second largest continent globally. Evaluation of research on renewable energy and Nigeria will be done to lay the facts bare and show the things that have to be put in place to start the process. The result will show that while there are constraints, Nigeria as a country will greatly benefit from policies based on renewables and unconventional energies.
The Contract Regime for Unitisation and the Impact of Production Sharing Contracts on Joint Development in Nigeria
Authors: James Mendos
Published: August 2021

Unitisation has evolved globally as the best mechanism for the joint development of hydrocarbon bearing reservoirs that straddle two or more concessions or licenses. The concept of unitisation is underpinned by the need to avoid competitive exploitation of hydrocarbon resources, maximise its economic recovery, eliminate proliferation of production facilities and reduce development and operating cost.1

The practice of unitisation in the Nigerian oil and gas landscape has gained traction over the years with several straddle fields identified as candidates for unitisation and more than ten (10) agreements for joint development (both Pre Unitisation Agreements and Unitisation and Unit Operating Agreements) executed in the industry. This has occurred under a regulatory regime for unitisation that has evolved from the concise provisions of Section 48 of the Petroleum (Drilling and Production) Regulation 1969 as amended, to the robust Guidelines for Unitisation issued by the Department of Petroleum Resources (DPR) in 2008 (revised in 2019) (Guidelines) in response to the complexities of joint development encountered by parties.

While the Guidelines is an excellent attempt at providing a process for unitisation, it does not provide sufficient guidance on the contract regime for unitisation as the bedrock for joint development. A critical look at the contracts governing joint development in the light of global best practices is important to ensure that it meets in an effective manner the objectives of unitisation. A review of the contract regime for unitisation would be incomplete without recognising the impact that underlying contracts governing separate concessions have on unitisation. To this end, the posture of Production Sharing Contracts (PSCs) on gas development in a unit is worth reviewing in the light of the benefits of commercialising gas to the State and the Contractor.

This paper reviews the contract regime for unitisation in Nigeria as regulated by the Guidelines and the impact that underlying contracts (particularly PSCs) have on unitisation. The paper will proffer recommendations for inclusion in the Guidelines with a view to improving the process of joint development of shared reservoirs in Nigeria.
Solid-Fluid Phase Equilibria Measurement for Mixtures of Methane, Carbon-Dioxide and N-Hexadecane
Authors: Eniolorunda Oluwakemi Victoria , Chapoy Antonin , Burgass Rod
Published: August 2021

In this study, new experimental data using a reliable approach are reported for solid-fluid phase equilibrium of ternary mixtures of Methane-Carbon-dioxide- n-Hexadecane for 30-73 mol% CO2 and pressures up to 24 MPa. The effect of varying CO2 composition on the overall phase transition of the systems were investigated. Three thermodynamic models were used to predict the liquid phase fugacity, this includes the Peng Robison equation of state (PR-EoS), Soave Redlich-Kwong equation of state (SRK-EoS) and the Cubic plus Association (CPA) equation of state with the classical mixing rule and a group contribution approach for calculating binary interaction parameters in all cases. To describe the wax (solid) phase, three activity coefficient models based on the solid solution theory were investigated: the predictive universal quasichemical activity coefficients (UNIQUAC), Universal quasi-chemical Functional Group activity coefficients (UNIFAC) and the predictive Wilson approach. The solid-fluid equilibria experimental data gathered in this experimental work including those from saturated and under-saturated conditions were used to check the reliability of the various phase equilibria thermodynamic models.
Application of Machine Learning Techniques in Reservoir Characterization
Authors: Okon Edet Ita , Appah Dulu
Published: August 2021

Application of artificial intelligence (AI) and machine learning (ML) is becoming a new addition to the traditional reservoir characterization, petrophysics and monitoring practice in oil and gas industry. Accurate reservoir characterization is the driver to optimize production performance throughout the life of a field. Developing physics-based data models are the key for applying ML techniques to solve complex reservoir problems. The main objective of this study is to apply machine learning techniques in reservoir Characterization. This was achieved via machine learning algorithm using permeability and porosity as the investigative variables. Permeability and porosity of a reservoir were predicted using machine learning technique with the aid of XLSTAT in Excel. The general performance and predictability of the technique as applied to permeability and porosity predictions were compared. From the results obtained, it was observed that the machine learning model used was able to predict about 98% of the permeability and 81% of the porosity. The results from Al and ML will reinforce reservoir engineers to carry out effective reservoir characterization with powerful algorithms based on machine learning techniques. Hence, it can therefore be inferred that machine learning approach has the ability to predict reservoir parameters.
Velocity Dependence and Tracer Dispersion in Newtonian Fluids Undergoing Creeping Flow
Authors: Ayuba Ibrahim , Akanji T. Lateef , Gomes J. L.
Published: August 2021

The dynamics of tracer particles in a viscous Newtonian fluid is studied analytically and numerically through channels of varying thickness for fluids undergoing creeping flow. Exact analytical solutions of mass conservation equations of tracer particles including consideration for pressure forces are obtained. Results of the analysis indicates that Stokes velocity is an indispensable parameter and is dependent on parameters such as channel thickness (height), viscosity of the fluid, pressure gradient driven the fluid and Reynolds number corresponding to the channel thickness. The accuracy of the solution obtained is verified by comparing its velocity profiles with those obtained from finite-element-based numerical simulation studies.
De-Risking Thermal Induced Sustained Annulus Pressure to Safeguard Optimal Production
Authors: Maxwell-Amgbaduba Sunday , Ogbonna David , Obakhena Femi , Okereke Onyedikachi , Green Ihuoma , Volkov Maxim , Oyanu Ruth
Published: August 2021

Sustained Annulus Pressure (SAP) is a common production constraint in the oil and gas industry, it is usually caused by impaired seal Integrity within the wellbore system resulting in barrier failures. In peculiar scenarios the thermal expansion creates pressure build-up in the annulus as well which can equally impair the integrity of the wellbore.

In this paper the results of downhole and surface pressure monitoring surveys are presented, the objectives aim at determination of both downhole leaks and verification the influence of thermal expansion into a wellbore system integrity in a field located onshore Niger Delta. SAP in a producing well was earlier recorded during routine annular pressure monitoring in 2017 during the production rate increase by changing the bean size from 18/64" to 24/64".

Initial diagnostics observed pointed towards SAP resulting from a possible downhole seal integrity issue leading to a leak to the surface. While putting the well on stream with current bean size and the pressure regime for both THP and CHP was observed. Pressure with time analysis showed annulus pressure builds up rapidly while flowing and bleeds off within 30 min from 700 psi to 0 psi when well shut in. Downhole logging and sensitive passive acoustic monitoring was conducted, the survey aimed to detect barrier failures by capturing its acoustic leak patterns under shut-in and bleeding off condition. Considering the suspected leak behaviour, the data acquisition included the procedure to build up the annulus pressure by flowing the well and monitoring the annulus discharge.

Integrity logs survey and passive acoustic monitoring confirmed there were no downhole failures and after several bleed-offs when Tubing choke was beaned down to 18/64" no annulus pressure build-up was observed from the Well head gauge on the Casing head confirming the source of the sustained annulus pressure is driven by the temperature expansion of the annulus fluid.

Remedial action and recommendation after Simulation were to de-risk the well at a controlled bean size to mitigate SAP and optimally flow the well.
Modeling and Predicting Performance of Autonomous Rotary Drilling System Using Machine Learning Techniques
Authors: Amadi Kingsley , Iyalla Ibiye , Prabhu Radhakrishna
Published: August 2021

This paper presents the development of predictive optimization models for autonomous rotary drilling systems where emphasis is placed on the shift from human (manual) operation as the driving force for drill rate performance to Quantitative Real-time Prediction (QRP) using machine learning. The methodology employed in this work uses real-time offset drilling data with machine learning models to accurately predict Rate of Penetration (ROP) and determine optimum operating parameters for improved drilling performance. Two optimization models (physics-based and energy conservation) were tested using Artificial Neutral Network (ANN) algorithm. Results of analysis using the model performance assessment criteria; correlation coefficient (R2) and Root Mean Square Error (RMSE), show that drill rate is non-linear in nature and the machine learning model (ANN) using energy conservation is most accurate for predicting ROP due to its ability in establishing a functional feature vector based on learning from past events.
Identification and Validation of Novel Endogenous Controls for qPCR Normalization in SK-BR-3 Breast Cancer Cell Line
Authors: Jain Nityanand , Mitre Ingrida , Nitisa Dina , Pirsko Valdis , Cakstina Inese
Published: August 2021

Normalization of gene expression using internal controls or reference genes (RGs) has been the method of choice for standardizing the technical variations in reverse transcription quantitative polymerase chain reactions (RT-qPCR). Conventionally, ACTB and GAPDH have been used as reference genes despite evidence from literature discouraging their use. Hence, in the present study we identified and investigated novel reference genes in SK-BR-3, an HER2-enriched breast cancer cell line. Transcriptomic data from 82 HER2-E breast cancer samples from TCGA database was analyzed to identify twelve novel genes with stable expression. Additionally, thirteen RGs from literature were analyzed. The expression variations of the candidate genes were studied over five successive passages (p) in two parallel cultures S1 and S2 and in acute and chronic hypoxia using various algorithms. Finally, the most stable RGs were selected and validated for normalization of the expression of three genes of interest (GOIs) in normoxia and hypoxia. Our results indicate that HSP90AB1, DAD1, PFN1 and PUM1 can be used in any combination of three (triplets) for optimizing intra- and inter-assay gene expression differences in the SK-BR-3 cell line. Additionally, we discourage use of conventional RGs (ACTB, GAPDH, RPL13A, RNA18S and RNA28S) as internal controls for RT-qPCR in SK-BR-3 cell line.
Relationship Between Factors Associated with Incidence of Medical Error in Iran
Authors: Estahbanati Ehsan Ahsani , Bevrani Hossein , Doshmangir Leila
Published: August 2021

Background

Providing safe, efficient, and quality services to all people is critical for achieving effective universal health coverage and the health-related sustainable development goals (SDGs) and in particular SDG 3.8. Medical error as a main challenge of delivery systems is a main influential factor on patient safety and quality of health care services. Investigating factors influencing on medical errors can help to improve quality patient safety. This study aimed to investigate the relationship between several contributed factors on incidence of medical errors in East Azarbaijan province, Iran.
Methods

We conducted a cross-sectional study, resulting in 10700 voluntary reporting of medical errors by medical staff working in all types of hospitals including public and non-educational, educational, private, military, charity and social security hospitals. Poisson regression was used for data analysis.
Results

The most frequency of medical errors reported by 41 studied hospitals was related to educational public hospitals, medical errors with no harm in the fall and the least frequency was related to non-educational public hospitals and surgical errors in the spring season. As the results show, spring and summer have a significantly lower incidence of medical error compared to winter (P < 0.001). Also, the incidence of medical error in the morning shift was significantly higher than the night shift (P < 0.001). According to the results, the incidence of errors with the consequence of near miss, no harm was significantly higher than the sentinel event error.
Conclusions

The results of the present study showed that the factors, different season, work shift, medical error type, medical error intensity and hospital type have a significant relationship with the incidence of medical error.
Identification of Potential Biomarkers in Synovial Tissue of Rheumatoid Arthritis via Integrated Microarray Analysis. Identification of Biomarkers of Rheumatoid Arthritis
Authors: Tao Li , Xiong ChaoLiang , Xue Li
Published: August 2021

Background: Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by synovitis and subsequent destruction of cartilage and bone. This study aimed to explore RA-related gene markers and the underlying molecular mechanism.Material and Methods: The expression profiles of GSE77298, GSE55235 and GSE12021 were obtained from the Gene Expression Omnibus database. Then, the differential gene expression analysis was conducted between GSE77298 and GSE55235 datasets. Limma package and a Venn diagram were utilized to screen the overlapping differentially expressed genes (DEGs), and Functional enrichment and pathway analysis were performed by using DAVID database. Subsequently, a protein-protein interaction (PPI) network was established, and candidate hub genes were recognized by using STRING and Cytoscape software. Finally, another dataset (GSE12021) was used for the validation of diagnostic value of the candidate hub genes and to identify real hub genes by using receiver operating characteristic (ROC) curves.Results: A total of 385 DEGs were detected, which include 19 downregulated genes and 366 upregulated genes. GO and KEGG pathway analysis showed that DEGs was mainly enriched in various immune and inflammatory response-related functions and pathways. The PPI network was composed of 374 nodes and 767 edges. A total of 8 real hub genes (HLA-DRA, HLA-DRB1, LCK, VAV1, HLA-DPA1, HLA-DPB1, C3AR1 and CD3D) which displayed an excellent diagnostic value for RA were identified.Conclusion: these findings may provide novel and reliable biomarkers for RA, which have some interesting implications for early diagnosis, prognosis and targeted therapy.
Effects of PPARγ agonist on the polarization of microglia around hematoma after intracerebral hemorrhage in male rats
Authors: Xu Yingning , Mu Qiong , Xue Fengfeng
Published: August 2021

Objective: To study the effect of PPARγ agonist (rosiglitazone) on the polarization of microglia around the hematoma after intracerebral hemorrhage in male SD rats. Materials and Methods: A total of 48 male SD rats were divided into a normal group (Control), the intracerebral hemorrhage model group (ICH), the sodium chloride intervention group (NaCl), and the rosiglitazone intervention group (RSG).ICH model of male rats was established by autologous blood. The neurological function of all groups of male rats was scored at 6, 24, 48, and 72h after modeling. The expression of CD16 (M1 marker) and CD206 (M2 marker) in the peripheral tissues of hematoma was detected by immunohistochemistry and Western blot. Results: Longa scores of the ICH and RSG group were significantly higher than those of the Control group and NaCl group at each time (P < 0.05). The RSG group's Longa score at 6, 24, and 48h was lower than that of the ICH group (P < 0.05). In the ICH group and RSG group, CD16 reached its peak at 6h and then decreased; the expression level of CD16 in the RSG group was lower than that in the ICH group at 6h (P < 0.05). The CD206 reached a peak at 24h; however, the expression level of CD206 in the RSG group was higher than in the ICH group (P < 0.05). Conclusion: PPARγ agonist stimulates the activation of M2 microglia , enhancing the ability to remove hematoma microglial cells.
Germin Like Protein Genes Exhibit Modular Expression During Salt and Drought Stress in Elite Rice Cultivars
Authors: Anum Jazba , O’Shea Charlotte , Hyder M Zeeshan , Farrukh Sumaira , Skriver Karen , Malik Saad Imran , Yasmin Tayyaba
Published: August 2021

Germin-like proteins (GLPs) are ubiquitous plant proteins, which play significant role in plant responses against various abiotic stresses. However, the potential functions of GLPs in rice (Oryza Sativa) against salt and drought stress are still unclear. In this study, transcriptional variation of 8 OsGLP genes (OsGLP3-6, OsGLP4-1, OsGLP8-4, OsGLP8-7, OsGLP8-10, OsGLP8-11 and OsGLP8-12) was analyzed in leaves and roots of two economically important Indica rice cultivars, KS282 and Super Basmati under salt and drought stress at early seedling stage. The relative expression analysis from qRT-PCR indicated the highest increase in expression of OsGLP3-6 in leaves and roots of both rice varieties with a significantly higher expression in KS282. Moreover, relative change in expression of OsGLP8-7, OsGLP8-10 and OsGLP8-11 under salt stress and OsGLP8-7 under drought stress was also commonly higher in leaves and roots of KS282 as compared to Super Basmati. Whereas, OsGLP3-7 and OsGLP8-12 after salt stress and OsGLP8-4 and OsGLP8-12 after drought stress were observed with higher relative expression in roots of Super Basmati than KS282. Importantly, the OsGLP3-6 and OsGLP4-1 from chromosome 3 and 4 respectively showed higher expression in leaves whereas most of the OsGLP genes from chromosome 8 exhibited higher expression in roots. Overall, as a result of this comparative analysis, OsGLP genes showed both general and specific expression profiles depending upon a specific rice variety, stress condition as well as tissue type. These results will increase our understanding of role of OsGLP genes in rice crop and provide useful information for the further in-depth research on their regulatory mechanisms in response to these stress conditions.
Recoverable Water-soluble Polyethylene Glycol-immobilized N-hydroxyphthalimide Mediated Oxidation of Cellulose in the Presence of NaBr and NaClO
Authors: Wang Huimin , Wang Xiaoying , Sun Tingting , Li Peixin , Chu Xiaomeng , Xing Xuteng , Liu Shaojie , Tang Erjun
Published: August 2021

As a highly efficient nitroxide radical catalyst for selective catalytic oxidation of cellulose, N-hydroxyphthalimide (NHPI) has attracted much attention because of its low price and light cellulose degradation. However, NHPI is insoluble in water and is difficult to recycle because of its small molecular weight. To address the above issues, the water-soluble polyethylene glycol (PEG)-immobilized NHPI catalyst (PEG-NHPI) was designed and prepared in this work. Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance spectroscopy (NMR), gel permeation chromatography (GPC) and UV-vis light spectroscopy were used to characterize PEG-NHPI. The results showed that PEG-NHPI catalysts with good water solubility and adjustable NHPI loading amounts were successfully synthesized. Using NaBr as promoter and NaClO as oxidant, PEG-NHPI mediated oxidation of cellulose was carried out and good catalytic performance was found. The catalytic performance of PEG-NHPI mediated oxidation of cellulose in water was higher than that in acetonitrile-water. The carboxyl content of PEG-NHPI oxidized cellulose could reach the level of free NHPI oxidized cellulose, and was equivalent to 68% of 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) oxidized cellulose, while the degradation degree of cellulose was greatly reduced by more than 40%. The catalytic performance did not decrease significantly after six oxidation cycles. The structure of recycled PEG-NHPI was not changed. These results indicated that immobilizing NHPI onto PEG can achieve the unification of high catalytic performance and good recyclability.
Health Beliefs and Behaviors of Livestock Industry Workers Regarding Crimean-Congo Hemorrhagic Fever in Northwest of Iran
Authors: Abazari Malek , Adham Davoud , Saghafipour Abedin , Taheri-Kharameh Zahra , Abbasi-Ghahramanloo Abbas , Asadollahi javad , Pouya Amin Babaei , Moradi-Asl Eslam
Published: August 2021

Background: Crimean-Congo hemorrhagic fever (CCHF) is an acute, feverous disease that is caused by tick bites or humans’ direct contact with the blood and tissues of infected livestock and humans. The transmission of the disease is also possible via human-to-human contacts and nosocomial transmission is well described. The majority of patients suffering from this disease are slaughterhouse workers (including butchers), farmers, veterinarians and hospital staff. Thus, this study aimed to investigate the health behaviors of butchers regarding CCHF and study factors affecting such behaviors based on the health belief model.Methods: This is a descriptive cross-sectional study conducted on 500 butchers in Ardabil Province in 2020 by a multistage sampling method. The participants of the study completed the researcher-made questionnaire of health belief model and health behaviors model relevant to CCHF. The collected data were then analyzed by descriptive statistical tests and linear regression analysis. Results: The mean (SD) age of the participants was 44.4 (10.5) years, and 96% were males. Only 11.1% of the participants displayed acceptable disease-preventive behaviors. The validity and reliability of the developed questionnaire were confirmed. The results of the exploratory factor analysis showed that the constructs of the model explained 84% of the total variance. The results of the study revealed that among the variables of the health belief model, perceived susceptibility (p-value = 0.006, β = 0.152) and perceived barriers (p-value = 0.023, β = 0.14) were the strongest factors predicting disease-preventive behaviors regarding CCHF.Conclusion: The results of the study showed that the health belief model can predict preventive behaviors for CCHF. Therefore, designing and executing interventions based on the results of this study may encourage such preventive behaviors in butchers.
Exploring Spatiotemporal Change of City and Village from Remote Sensing Using Multi-Branch Networks
Authors: Zhao Mengqi , Tian Yan
Published: August 2021

With the rapid development of social economy, the urban and rural environment, form and infrastructure have also under- gone earth-shaking changes. As a gathering place for human activities, urban and rural areas play a vital role in the interaction between humans and society. If traditional machine learning methods are used to perceive changes in the intentional connotation of urban and rural areas, it is easy to ignore the detailed information of the intentional target. At the same time, the perception accuracy needs to be improved. Therefore, the deep neural network in this paper proposes a way to perceive the temporal and spatial changes of urban and rural intentional connotations from the perspective of remote sensing. The framework first uses the multi-branch DenseNet to capture the multi-scale spatiotemporal information of the intended target, and embeds it with high-level semantics and low-level physical appearance information. Secondly, a multi-branch cross-channel attention module is designed to perform reﬁned and integrated processing of multi-level spatiotemporal information to realize the aggregation of multi-branch information. Finally, it was tested and verified on two different time data sets, and good performance was achieved.
Stability of SARS-CoV-2 on Cold-chain Food
Authors: Liu Yongjian , Li Tianyi , Guo Yaolin , Li Hanping , Jia Lei , Zhang Dong , Wang Xiaolin , Han Jingwan , Li Lin , Li Jingyun
Published: August 2021

Although close exposure to respiratory droplets from an infected patient is the main transmission route of SARS-CoV-2, touching contaminated surfaces and objects might also contribute to transmission of this virus. There are increasing reports that cold-chain food and food packages have been tested with SARS-CoV-2, raising concerns that importation of contaminated food could be a source for transmission of SARS-CoV-2. The survival of SARS-CoV-2 on cold-chain food was investigated. We found SARS-CoV-2 remained viable for more than three weeks on both beef and mutton at 4°C. Furthermore, at freezing temperature, SARS-CoV-2 can easily survive for more than eight weeks. Our study showed the ability of SARS-CoV-2 to survive for a long time on cold-chain food at low temperatures.
Detection of Martian Dust Storms Using Mask-Regional Convolutional Neural Networks
Authors: Alshehhi Rasha , Gebhardt Claus
Published: August 2021

Martian dust plays a crucial role in the meteorology and climate of the Martian atmosphere. It heats the atmosphere, enhances the atmospheric general circulation, and affects spacecraft instruments and operations. Compliant with that, studying dust is also essential for future human exploration. In this work, we present a method for the deep-learning-based detection of the areal extent of dust storms in Mars satellite imagery. We use a mask regional convolutional neural network (R-CNN), consisting of a regional-proposal network (RPN) and a mask network. We apply the detection method to Mars Daily Global Maps (MDGMs) of the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC). We use center coordinates of dust storms from the eight-year Mars Dust Activity Database (MDAD) as ground-truth to train and validate the method. The performance of the regional network is evaluated by the average precision score with 50% overlap (mAP50), which is around 62.1%.
External Lumbar Drainage for Refractory Intracranial Hypertension in Traumatic Brain Injury: A Systematic Review
Authors: Stevens Andrew Robert , Soon Wai Cheong , Chowdhury Yasir Arafat , Toman Emma , Belli Antonio , Davies David James
Published: August 2021

BackgroundExternal lumbar drainage remains a controversial therapy for medically refractory intracranial hypertension in patients with acute TBI. This systematic review sought to compile the available evidence for the efficacy and safety of the use of lumbar drains for ICP control. MethodsA systematic review of the literature was performed with the search and data extraction performed by two reviewers independently in duplicate.ResultsNine independent studies were identified enrolling 230 patients, 159 with TBI. Efficacy for ICP control was observed across all studies, with immediate and sustained effect, reducing medical therapy requirements. Lumbar drainage with medical therapy appears effective when used alone and as an adjunct to ventricular drainage. Safety reporting varied in quality. Cerebral herniation (with unclear relationship to lumbar drainage) was observed in 14/230 patients resulting in one incident of morbidity without adverse patient outcome. ConclusionsThe available data is generally poor in quality and volume, but supportive of efficacy of lumbar drainage for ICP control. Few reports of adverse outcome are suggestive of, but are insufficient to confirm, safety of use in the appropriate patient and clinical setting. Further large prospective observational studies are required to generate sufficient support of an acceptable safety profile.
Biotransformations of HBCDs by Rhodococcus Strain Stu-38 and Identification of Transformation Products
Authors: Yu Fei , Luo Wenqi , Li Yuyang , Meng Shanshan , Lin Xianbin , Li Lele , Ye Xueying , Wang Hui , Peng Tao , Huang Tongwang , Hu Zhong
Published: August 2021

1, 2, 5, 6, 9, 10-Hexabromocyclododecanes (HBCDs) are new brominated flame retardants causing serious environmental pollution. Dozens of degradative bacteria have been found with capacity to transform HBCDs. In the present study, an aerobic functional bacterium Rhodococcus strain stu-38 was isolated from enriched culture of mangrove sediment using HBCDs as carbon source. This strain could stereoselectively transform HBCDs, the removal rate was α-＞γ-＞β-HBCD in the mineral salt medium, but was β-＞α- and γ-HBCD in the growth medium, and it selectively transformed γ- HBCD in the seawater. Transformation rate of strain stu-38 was lower than other functional strains, however, seven potential debrominated products of HBCDs were identified by using GC-MS. These debrominated products, included dibromocyclododecadiene, bromocyclododecadienol and bromocyclododecatriene were formed through reductive debromination, hydrolytic debromination and dehydrobromination. Overall, Rhodococcus sp. stu-38 diastereoisomer-specifically transformed HBCDs to various debrominated products in the different cultural media, which highlighted the complicated stereoselective biotransformation of HBCDs.