bluuebunny/crossref_metadata_2025 huggingface dataset:
Developments on Metal Sulfide Scale Management in Oil and Gas Production
Authors: Bhandari Narayan , Bhandari Manojkumar , Littlehales Ian , Potter Sean
Published: November 2021

Metal sulfide scaling issue in the oil and gas production continue to present significant flow assurance challenge. Recently, a novel polymeric chemistry that can effectively control FeS scale deposition in oil and gas production system was reported. However, how to manage finely dispersed FeS particulates at surface disposal facilities and whether this polymer is capable of mitigating ZnS and PbS deposition is largely unknown. Therefore, this study continues to seek an efficient treatment option for metal sulfide scale management.

Static bottle tests and dynamic scale loop tests under anoxic conditions were conducted to understand the efficacy of the novel polymeric chemistry towards metal sulfide scaling control. To mimic various field conditions; individual metal sulfide (FeS, ZnS and PbS) as well as mixed scaling scenarios were simulated. Various coagulant and oxidant chemistries were tested to understand the impact of the upstream treatment on safe disposal of FeS nanoparticles at surface facilities.

This novel polymeric chemistry was found to be not only effective towards FeS scaling control, but also towards dispersion of ZnS and PbS as well. The primary mechanism of metal sulfide scale deposition control is identified to be crystal growth inhibition and crystal surface modification. Laboratory test results indicated no negative impact of new chemistry on the performance of other chemicals (coagulant, oxidizer etc.). In fact, an enhanced efficiency of iron sulfide oxidation was observed possibly due to the large surface area of finely dispersed particles. A field throughput study results indicated superior performance compared to that of various incumbent chemistries.

Based on the laboratory results, it is anticipated that this chemistry will provide a new treatment option for metal sulfide scaling/deposition control. Additionally, the new chemistry did not leave any negative footprint for safe disposal of metal sulfide particulate at surface. As opposed to the calcite/barite scale, nucleation inhibition of metal sulfide may not be desired as the dissolved sulfide may cause further corrosion/deposition downstream. Therefore, the value this paper brings to the management of metal sulfides is a systematic testing and evaluation approach which confirms dispersion rather than nucleation inhibition is effective control mechanism.
Seawater Breakthrough Monitoring and Reservoir-Model Improvement Using Natural Boron
Authors: Wang Yanqing , Liu Zhe , Li Xiang , Xu Shiqian , Lu Jun
Published: November 2021

Natural geochemical data, which refer to the natural ion concentration in produced water, contain important reservoir information, but is seldomly exploited. Some ions were used as conservative tracers to obtain better knowledge of reservoir. However, using only conservative ions can limit the application of geochemical data as most ions are nonconservative and can either interact with formation rock or react with other ions. Besides, mistakenly using nonconservative ion as being conservative may cause unexpected results. In order to further explore the nonconservative natural geochemical information, the interaction between ion and rock matrix is integrated into the reservoir simulator to describe the nonconservative ion transport in porous media. Boron, which is a promising nonconservative ion, is used to demonstrate the application of nonconservative ion. Based on the new model, the boron concentration data together with water production rate and oil production rate are assimilated through ensemble smoother multiple data assimilation (ES-MDA) algorithm to improve the reservoir model. Results indicate that including nonconservative ion data in the history matching process not only yield additional improvement in permeability field, but also can predict the distribution of clay content, which can promote the accuracy of using boron data to determine injection water breakthrough percentage. However, mistakenly regarding nonconservative ion being conservative in the history matching workflow can deteriorate the accuracy of reservoir model.
Development and Application of a Novel Hydrogen Sulfide Scavenger for Oilfield Applications
Authors: Lehrer Scott , Jani Jagrut , Ramachandran Sunder , Liu Zhengwei
Published: November 2021

Currently used scavengers in mixed production applications can have issues with poor efficiency and thermal stability (triazines, glyoxal), scaling tendency (triazines), corrosivity (glyoxal), and emulsification (metal-based scavengers). Research was conducted which resulted in a new scavenger that avoids negative side effects while maintaining efficient performance over a wide range of applications. The application of this scavenger into mixed production can avoid or reduce the need for H2S removal post-separation, thereby reducing overall cost.

The development and field application of a new Hydrogen Sulfide (H2S) Scavenger in oilfield mixed production applications is presented. Several field applications will be discussed comparing the overall performance of this new H2S scavenger with existing technologies. Field application results will show that this novel scavenger avoids issues with currently used scavengers including poor efficiency, corrosivity, scaling, and emulsification. This new H2S scavenger technology is suitable for both surface and downhole injection. It will be demonstrated how removing H2S upstream in mixed production can save overall treatment cost.
Pore–Scale Numerical Investigations of the Impact of Mineral Dissolution and Transport in Naturally Fractured Systems During CO2–Enriched Brine Injection
Authors: You Jiahui , Lee Kyung Jae
Published: November 2021

CO2 storage and sequestration are regarded as an effective approach to mitigate greenhouse gas emissions. While injecting an enormous amount of CO2 into carbonate–rich aquifers, CO2 dissolves in the formation brine under the large pressure, and the subsequently formed CO2–enriched brine reacts with the calcite. Reaction–induced changes in pore structure and fracture geometry alter the porosity and permeability, giving rise to concerns of CO2storage capacity and security. Especially in the reservoir or aquifer with natural fractures, the fractures provide a highly permeable pathways for fluid flow. This study aims to analyze the acid–rock interaction and subsequent permeability evolution in the systems with complex fracture configurations during CO2 injection by implementing a pore–scale DBS reactive transport model. The model has been developed by expanding the functionality of OpenFOAM, which is an open–source code for computational fluid dynamics. A series of partial differential equations are discretized by applying the Finite Volume Method (FVM) and sequentially solved. Different fracture configurations in terms of fracture length, density, connection, and mineral components have been considered to investigate their impacts on the dynamic porosity–permeability relationship, dissolution rate, and reactant transport characteristics during CO2 storage. The investigation revealed several interesting findings. We found that calcium (Ca) concentration was low in the poorly connected area at the initial time. As CO2–enriched brine saturated the system and reacted with calcite, Ca started being accumulated in the system. However, Ca barely flowed out of the poor–connected area, and the concentration became high. Lengths of branches mainly influenced the dissolution rates, while they had slight impacts on the porosity–permeability relationship. While fracture connectivity had an apparent influence on the porosity–permeability relationship, it showed a weak relevance on the dissolution rate. These microscopic insights can help enhance the CO2 sealing capacity and guarantee environmental security.
Uncovering Mysteries of Waxphaltenes: Meticulous Experimental Studies of Field and Lab Deposits Unveil Nature of Wax-Asphaltene Intermolecular Interactions
Authors: Aguiar Janaina I. S. , Samouei Hamidreza , Mahmoudkhani Amir
Published: November 2021

In recent years, the utilization of modern sampling tools provided access to the field deposits from several offshore and onshore wells producing asphaltenic crudes. Compositional analysis of field deposits revealed the presence of asphaltenes and wax as major fractions, while system conditions traditionally implied precipitation and deposition of asphaltenes only. Most of the previous studies on organic deposition have been conducted with the key assumption that aggregation and precipitation of wax and asphaltene occur independently. A few researchers investigated the solubility parameter's alteration, but they did not incorporate waxes found in the oilfield deposits. This study aims to investigate the nature of "waxphaltenes"; from intermolecular interactions between asphaltenes and wax in samples collected from fields and made in the laboratory. Asphaltenes samples were extracted and fully characterized by proton nuclear magnetic resonance (NMR) and Fourier-transform infrared spectroscopy (FTIR). Paraffin waxes were identified using gas chromatography (GC), differential scanning calorimetry (DSC), NMR, and FTIR. Precipitation tests of asphaltenes with n-heptane at high temperature were performed both in the presence and absence of wax; GC, NMR and FTIR techniques evaluated the precipitates and the material dispersed in solution. It was found that asphaltenes co-precipitated with waxes even at higher temperatures than the normal wax appearance temperature (WAT) of the crude oil or the model solutions and that long and medium size paraffin waxes had higher tendencies to coprecipitate with asphaltenes than either short chain or very long chain paraffin hydrocarbons. The results also indicated that the amount of wax that co-precipitates with asphaltenes was more related to asphaltene structure but is independent of the asphaltenes or wax content. Heteroatoms played an important role in the interactions between wax and asphaltenes during precipitation and separation.
Preventing Wax Deposition in Crude Oil Using Polyethylene Butene and Nano Zinc Oxide
Authors: Balogun Ademola , Odutola Toyin , Balogun Yakubu
Published: November 2021

This research examines the use of 75nm Zinc Oxide nanoparticles (Nano ZnO) and Polyethylene Butene (PEB) in reducing the viscosity of Nigerian waxy crude oil. The rheology of the crude oil was studied by measuring the viscosity and shear stress of crude samples contaminated with varying concentration of PEB (500ppm, 1000ppm, 2000ppm, 3000ppm, 4000ppm and 5000ppm), varying concentrations of Nano ZnO (1wt%, 2wt%, 3wt% and 4wt%) and different blends of PEB and Nano ZnO at temperatures of between 10°C to 35°C and shear rates from 1.7 to 1020s-1. From Rheological Modelling analysis conducted, the Power law pseudoplastic model was the best fit for the experimental data with a regression coefficient of 0.99. Analysis of crude sample before addition of inhibitor showed evidence of non-Newtonian fluid behaviour as the shear stress-shear rate relationship curves were nonlinear due to wax precipitation at low temperatures (10°C to 15°C). The waxy crude demonstrated shear thinning behaviour with increasing shear rates (increasing turbulence) and the viscosity reduced with increasing temperature. The addition of inhibitors (PEB, Nano ZnO and their blends) effected Newtonian fluid behaviour in the crude samples as the shear stress-shear rate relationship curves were linear at all temperatures under study. The optimum concentration of the inhibitors in this study is 2000ppm PEB (causing 33% viscosity reduction) and 1wt% Nano ZnO (effecting 26% viscosity reduction). The best concentration of the blend was 2000ppm PEB blended with 1wt% Nano ZnO which effected a viscosity reduction of 41%. The research demonstrates the novel application of the blend of Nano ZnO and PEB in improving flowability of Nigerian waxy crude oil especially in offshore conditions with prevailing cold temperatures.
The Combined Flooding of Dispersed Particle Gel and Surfactant for Conformance Control and EOR: From Experiment to Pilot Test
Authors: Yin Xia , Zhao Tianyi , Yi Jie
Published: November 2021

The water channeling and excess water production led to the decreasing formation energy in the oilfield. Therefore, the combined flooding with dispersed particle gel (DPG) and surfactant was conducted for conformance control and enhanced oil recovery in a high temperature (100-110°C) high salinity (>2.1×105mg/L) channel reservoir of block X in Tahe oilfield.

This paper reports the experimental results and pilot test for the combined flooding in a well group of Block X. In the experiment part, the interfacial tension, emulsifying capacity of the surfactant and the particle size during aging of DPG were measured, then, the conformance control and enhanced oil recovery performance of the combined flooding was evaluated by core flooding experiment. In the pilot test, the geological backgrounds and developing history of the block was introduced. Then, an integrated study of EOR and conformance control performance in the block X are analyzed by real-time monitoring and performance after treatment. In addition, the well selection criteria and flooding optimization were clarified.

In this combined flooding, DPG is applied as in-depth conformance control agent to increase the sweep efficiency, and surfactant solution slug following is used for improve the displacement efficiency. The long term stability of DPG for 15 days ensures the efficiency of in-depth conformance control and its size can increase from its original 0.543μm to 35.5μm after aging for 7 days in the 2.17×105mg/L reservoir water and at 110°C. In the optimization, it is found that 0.35% NAC-1+ 0.25% NAC-2 surfactant solution with interfacial tension 3.2×10-2mN/m can form a relatively stable emulsion easily with the dehydrated crude oil. In the double core flooding, the conformance control performance is confirmed by the diversion of fluid after combined flooding and EOR increases by 21.3%. After exploitation of Block X for 14 years, the fast decreasing formation energy due to lack of large bottom water and water fingering resulted in a decreasing production rate and increasing watercut. After combined flooding in Y well group with 1 injector and 3 producers, the average dynamic liquid level, daily production, and tracing agent breakthrough time increased, while the watercut and infectivity index decreased. The distribution rate of injected fluid and real-time monitoring also assured the conformance control performance. The oil production of this well group was increased by over 3000 tons.

Upon this throughout study of combined flooding from experiment to case study, adjusting the heterogeneity by DPG combined with increasing displacement efficiency of surfactant enhanced the oil recovery synergistically in this high salinity high temperature reservoir. The criteria for the selection and performance of combined flooding also provides practical experiences and principles for combined flooding.
Storage of CO2 and Coal Fly Ash using Pickering Foam for Enhanced Oil Recovery
Authors: Lv Qichao , Zhou Tongke , Zhang Xing , Guo Xinshu , Dong Zhaoxia
Published: November 2021

CO2 foams have been used for a long time for enhanced oil recovery (EOR) and carbon capture, utilization, and storage. Note that conventional CO2 foam focuses on mobility control and storage of bare CO2. However, this technology has suffered from low storage efficiency and EOR because of foam instability. In this study, the geological storage of CO2 and coal fly ash (CFA) using Pickering foam for EOR was explored. The aim is to obtain an inexpensive method for EOR and storage of greenhouse gases and atmospheric pollutants.

The Pickering foam was prepared using Waring blender method. The experiments were conducted to evaluate CO2/liquid interface enhancement by measuring the interfacial tension and interfacial viscoelastic modulus. As per the heterogeneous sandpack flooding experiments, the profile control capacity and the performance of oil displacement using CO2 foam enhanced by CFA were investigated. The amount of storage from dynamic aspects of CO2 and CFA was measured to demonstrate the storage law.

The stability of aqueous foam was improved significantly after the addition of CFA. The half-life time of foam stabilized by CFA particles increased by more than about 11 times than that of foam without CFA particles. The interfacial dilatational viscoelastic modulus of CO2/foaming solution increased with CFA particle concentration increasing, indicating the interface transformed from liquid-like to solid-like. Flooding experiments in heterogeneous porous media showed that more produced fluid was displaced from the relatively low-permeability sandpack after the injection of CO2 foam with CFA. The oil recovery by CFA stabilized foam was improved by ~28.3% than that of foam without CFA particles. And the sequestration of CO2 in heterogeneous porous media was enhanced with the addition of CFA to CO2 foam, and the CFA stabilized foam displayed a strong resistance to water erosion for the storage of CO2 and CFA.

This work introduces a win–win method for EOR and storage of CO2 and atmospheric pollutant particles. CFA from coal combustion was used as an enhancer for CO2 foam, which improved the interfacial dilatational viscoelasticity of foam film and the dynamic storage of CO2. Furthermore, the storage of CO2 and CFA contributed to improvement in sweep efficiency, and thus EOR.
Enhancing Performance of High Viscosity Friction Reducers HVFRs in Brine
Authors: Phatak Alhad , Seymour Brian , Ren Ginger , Gonzalez Isaias
Published: November 2021

High Viscosity Friction Reducers (HVFRs) are often employed in hydraulic fracturing fluids to increase the proppant carrying capacity of slickwater fluids. However, it has been widely reported that the performance of HVFR fluids drops precipitously with even small amounts of salt. This study explores and reports the use of surfactants to alleviate the loss of performance of HVFR fluids due to salinity in the mix water. Fracturing fluids were prepared in the laboratory by mixing the HVFR at concentrations between 2 and 8 gal/1,000 gal with and without surfactant formulations. The viscosities of the fluids were measured on a TA Instruments DHR-3 rheometer using a concentric cylinder geometry. Both anionic and cationic HVFRs were tested with various surfactants. As expected, we observed that HVFR fluids display dramatic loss of viscosity with the addition of as little as 1% salt to the mix water. However, certain surfactant formulations were found to provide a significant boost in viscosity of HVFR fluids in brines over a wide range of shear rates. Increases in viscosity by a factor of as much as 10 times were observed, particularly at low shear rates. The ability of the surfactant formulations to enhance fluid viscosity was observed in both monovalent and divalent model brines, as well as brines that mimicked field produced water compositions. In addition, measurements were also performed in a slot flow device to determine if the results from the rheometer translated to proppant transport characteristics of the fluids. The slot flow results were found to correlate well with fluid viscosity measurements. The fluids containing the surfactant formulation transported nearly 4 times as much proppant as fluids not containing surfactant through a 2.5 ft. long rectangular slot of 0.5 in. thickness at a proppant concentration of 2 lb/gal. An obvious benefit of the approach proposed in this study is that it can enable the use of HVFR fluids in recycled and produced waters, providing both cost and sustainability benefits. Secondly, these surfactant formulations can reduce the amount of HVFR required to obtain a certain target viscosity in brine, thereby reducing the likelihood and potential severity of formation damage from HVFR residue.
Novel H2S Scavenger Testing Methodology to Meet the Ever-Present Challenge of Simulating Scavenger Application Methods with Laboratory Testing Protocols
Authors: Taylor Grahame , Wylde Jonathan , Allan Bridgette
Published: November 2021

The design methodology for H2S scavengers relies heavily on developing a test protocol that most closely simulates field applications. These include gas contact towers, direct gas production injection and multiphase treatments, such as subsea umbilical delivery lines to sea floor well heads, hydrocarbon flow lines and sour storage tank treatments. There are very few testing standards and while there are industry accepted methods, the novel methods presented fill the gaps that exist.

A thorough review is made of existing test methodologies such as the static gas breakthrough test and the multiphase Parr Autoclave. Each of these has become an accepted, albeit unofficial, industry standard. Novel methods recently developed comprise the "Direct Injection Laboratory Simulator" (DILS) which, as the name suggests, represents a laboratory method of evaluating a direct gas injection application. Also included is a unique modification of the gas breakthrough test, known as the "miniature Ultrafab tower" which simulates a regenerative tower-based system, commonly in operation in the field.

The results showed fascinating validation of gas direct injection and dynamic tower interactions. In some cases, the results are as expected and in others fresh insight has been obtained into any observed discrepancy between a scavenger's field performance and how it performs in the laboratory development studies. In the case of the "miniature Ultrafab tower", this ingenious piece of equipment has been proven to accurately simulate the packing typically seen in the gas contactor to enhance gas/liquid interaction as well as provides the ability to continually replenish the tower with fresh chemical during the test using an accurately controlled flow rate from an HPLC pump. These have been shown to be vitally important parameters for accurate lab to field correlation and are uniquely available from this test, for example gleaning the minimum flow rate of fresh scavenger which can control the H2S concentration to the predetermined level; exactly as is done in field operations. This novel apparatus also has a separator chamber where the spent chemical can be collected, analyzed and evaluated, exactly as is done in a field trial for a dynamic contact gas tower.

Armed with a new series of test methodologies, the development of H2S scavengers can enjoy a much higher success rate in the all-important transition from laboratory to field. The test methods also give invaluable tools to trouble shooting and investigate unexpected deficiencies in products which have in the past performed as expected. This includes providing a validation method for changes and enhancements desired during the manufacture process and raw material sourcing for chemical scavengers.
Innovative Surfactant Chemistry Offers the Performance Advantages to Invert Emulsion Drilling Fluids While Drilling Under Challenging Environments
Authors: Patel Arvindbhai , Singh Anil Kumar , Bidwai Nikhil , Indulkar Sakshi , Gupta Vivek
Published: November 2021

Stable invert emulsion with oil wet solids is achieved using invert emulsifiers and wetting agents. This paper reviews the chemistry and performance criteria of traditional invert emulsifiers and wetting agents utilized in formulating stable invert emulsion drilling fluids. However, occasionally such stable invert emulsion drilling fluids can be destabilized due to various hostile conditions encountered during drilling operation, and can adversely impact the drilling cost. Extreme preventive measures cannot avoid such hostile conditions such as sudden water influx, excessive solids and salt contaminations during drilling. Upon solids becoming extremely water wet with "flipped emulsion", it becomes impossible to fix the drilling fluid, resulting in expensive maneuver. Often situation cannot be corrected with traditional wetting agents and emulsifiers even at high level of treatments.

New innovative chemistry addresses the severe water-wetting and emulsion instability of invert emulsion under extreme challenging and hostile situations. The unique water soluble oil mud conditioner (OMC) synergistically enhances the performances of traditional oil-wetting agents and emulsifiers at very low, as little as 0.5 ppb levels of treatment. This OMC improves and extends the efficacy of the traditional invert emulsifiers and oil wetting agents resulting in reduced usage of these additives with excellent economic advantages.

The 15.0 ppg, invert emulsion drilling fluids were prepared using 2-3 ppb of primary and secondary emulsifiers, and these fluids were destabilized using high shear mixer for 7-8 hours. The destabilized fluids had severe water wet solids and ES value of less than 5. These destabilized fluids, upon treating with 0.5 ppb of newly developed OMC instantly became oil-wet and shiny and ES was increased to greater than 500. To demonstrate the effectiveness of OMC in pre-treatment situation, the base fluids treated with 0.5 −1.0 ppb of OMC showed superior mud stability compared to base fluid when contaminated with sea water, fine solids, barite and high salt contaminations. The OMC is flexible in its application and can be used as pre-treatment to improve the overall performance of drilling fluids and can also be used for post-treatment to recover the drilling fluids, which have been rendered unusable.
A Semiempirical Model for Predicting Celestite Scale Formation and Inhibition in Oilfield Operating Conditions
Authors: Zhao Yue , Dai Zhaoyi Joey , Dai Chong , Paudyal Samridhdi , Wang Xin , Ko Saebom , Yao Xuanzhu , Leschied Cianna , Kan Amy , Tomson Mason
Published: November 2021

Mineral scale formation has always been a serious problem during production. Most scales can be treated by adding threshold scale inhibitors. Several crystallization and inhibition models have previously been reported to predict the minimum inhibitor concentration (MIC) needed to control the barite and calcite scale. Recently, more attentions have been paid to the formation of celestite scale in the oilfield. However, no related models have been developed to help determine the MIC needed for the celestite scale control. Therefore, in this study, the crystallization and inhibition kinetics data of celestite under a wide range of celestite saturation index (SI = 0.7 – 2.6), temperature (T = 25 – 90 °C), ionic strength (IS = 1.075 – 3.075 M) and pH (4 – 6.7) with one phosphonate inhibitor (diethylenetriamine penta(methylene phosphonic acid, DTPMP) and two polymeric inhibitors (phophinopolycarboxylate, PPCA and polyvinyl sulfonate, PVS) were measured by laser apparatus or collected from previous studies. Then, based on the results, the celestite crystallization and inhibition models were established accordingly. Good agreements between the experimental results and calculated results from the models can be found. By using these newly developed models, the MIC needed for three commonly seen inhibitors, DTPMP, PPCA and PVS on celestite scale control can be predicted under extensive production conditions. The developed models can fill in the blank in scaling management strategies for high Sr2+ and SO42- concentrations in the produced waters.
Flow Dynamics of Microemulsion-Forming Surfactants and its Implications for Enhanced Oil Recovery: A Microfluidic Study
Authors: Yu Fuwei , Wang Lida , Liu Ben , Ma Mengqi , Liu Fan , Kang Lixia , Jiang Hanqiao , Li Junjian
Published: November 2021

The microfluidic experiments were conducted in this paper to clarify the flow dynamics of in situ microemulsion and further understand its EOR performances. Two kinds of 2.5D glass micromodel with varied depths of pore and throat are fabricated. One is designed for the imbibition tests, which consists of two fractures and a tight matrix. Another one is a fractured micromodel designed for the flooding tests. The micromodels are originally water wet, and can be altered to oil wet through the surface modification. At the same time, three microemulsion-forming surfactant solutions at the salinity of type I, II or III were prepared, respectively. Then the flow dynamics of these three surfactant solutions during imbibition and flooding process were visualized by the microfluidic experiments. Results show that the type I surfactant solution realizes the highest oil recovery rate in both water-wet and oil-wet imbibition micromodels. Meanwhile, the type III surfactant solution realize the highest oil recovery in both water-wet and oil-wet fractured micromodels.
Wellbore Integrity and CO2 Sequestration Using Polyaramide Vesicles
Authors: Contreras Elizabeth Q. , Santra Ashok
Published: November 2021

A new cementing additive is chemically engineered to react with formation fluids that act antagonistically towards cement. Engineered polymer capsules house encapsulants to react with antagonistic gases downhole like CO2 to form a more benign and beneficial material. Embedded in cement, the polymer capsules with semi-permeable shells allow fluids to permeate and react with encapsulants to produce beneficial byproducts, such as calcite and water from CO2. Reactivity between the encapsulant and antagonist gas CO2 is demonstrated using thermal gravimetric analysis (TGA) and other tests from oilfield equipment.

When cement fails, casing-in-casing events, or CCA, causes antagonistic gases like CO2 to migrate to the surface. Embedded in the cement for such moments such as cement failure, additives housed within polyaramide vesicles chemically and physically intersect CO2 from gas migration events. The shape of the polyaramide additive is unique and versatile. Furthermore, because the material is polymeric, it imparts beneficial mechanical properties like elasticity to cement. A vesicle in form, this polymer allows the manufacturing of new cement additives for applications such as increasing the integrity and sustainability of oil well cement. Data also shows production of calcite by the bulk of the material. This technology applies to CO2 fixation and self-healing cement using reactive polymer vesicles.
Influencing Factors of Lung Cancer Patients' Participation in Shared Decision-making: a Cross-sectional Study
Authors: Wang Ying , Zhang Jinna , Hu Bo , Wang Jizhe , Zhang Laixiang , Li Xiaohua , Zhu Xiuli
Published: November 2021

Purpose: The purpose of this study was to investigate and analyze the level of actual participation and perceived importance of shared decision-making on treatment and care of lung cancer patients, to compare their differences and to explore factors that influence them.Methods: A total of 290 lung cancer patients were collected from the department of oncology and thoracic surgery of a comprehensive medical center in Qingdao from October 2018 to December 2019. Participants completed a cross-sectional questionnaire to assess their actual participation and perceived importance in shared decision-making on treatment and care. Descriptive analysis and non-parametric tests were carried out to assess the status quo of patients' shared decision-making on treatment and care. Binary logistic regression analysis with a stepwise back-wards was applied to predict the factors that affected patients' participation in shared decision-making.Results: The results showed that patients with lung cancer had a low degree of participation in shared decision-making. There were significant differences between actual participation and perceived importance of shared decision-making on treatment and care. Education level, younger, gender, income, marital status, personality, the course of the disease (>6 months), and the Pathological TNM staging (Ⅲ) affected the patient's level of participation in shared decision-making.Conclusion: Actual participation in shared decision-making for the treatment and care of lung cancer patients was low and considered unimportant. We could train oncology nurses to use patient decision aids to help patients and families participate in shared decision-making based patients’ value, preferences and needs.
Expression of Sortilin in Pancreatic Carcinoma and Influence of Pancreatic Cancer Cells by Sortilin siRNA Knockdown
Authors: Xu Di , Yu Fang , Liu shangqing , Cai Rong
Published: November 2021

Background: Currently, there are few effective therapeutic options for pancreatic cancer patients.Sortilin is a member of vps10p receptor family，reported in many types of cancers.However, the underlying mechanism and prognostic value of sortilin in pancreatic cancer are still unclear.Objective:Understand the expression of sortilin in pancreatic cancer, and analyze its mechanism that affects the occurrence and development of pancreatic cancer.Methods:A tissue microarray of 115 pancreatic cancer metastases was analyzed by immunohistochemistry. All data were analyzed by univariate analysis and multivariate analysis.Multivariate logistic regression analysis and the area under the receiver operating characteristic (ROC) curve were used to analyze the ability of sortilin in predicting pancreatic cancer.Next, survival analysis was performed to compare the survival time between high-risk and low-risk patients to validate the prognosis prediction efficacy of sortilin.The effects of sortilin on the invasion，metastasis and proliferation of pancreatic cancer cells were investigated both in vitro. investigate the anti-cancer effect of soritlin on human pancreatic cancer Capna1 and Bxpc3 cells, and its possible molecular mechanism.Results:Differential expression analysis of 115 tissue microarrays showedsortilin expression was up‐regulated in pancreatic cancer tissues,and it mainly comes from the nucleus. Sortilin expression in nucleus(SEIN) was only negatively correlated with N stage, Binary logistic regression model showed that SEIN is a good diagnostic marker for predicting pancreatic cancer and the accuracy of prediction is as high as 79.1 %. ROC curve analysis demonstrated a statistically significant diagnostic value of SEIN,and the diagnostic accuracy was 86.3%, The Youden Index was calculated to evaluate the diagnostic power, The cut-off value for SEIN in pancreatic cancer diagnosis was 0.85, with a sensitivity of 90.9% and a specificity of 68.3%. Univariate analysis showed that M stage(P=0.022), histological grade(P=0.021), clinic stage(P=0.030)and SEIN(P=0.039) were correlated with prognosis of pancreatic cancer patients, Multivariate regression analysis showed that M stage(P=0.036)and ESIN(P=0.004) were independent factors.The proliferation, invasion and migration of pancreatic cancer cells were inhibited in vitro by sortilin siRNA knockdown.it may have something to do with soritlin/P53/NFκB regulated the the proliferation function and sortilin/MMP9 regulated the invasion-promotion of pancreatic cancer cells.Conclusions: These fndings demonstrated that the low expression of SEIN indicates better prognosis in pancreatic cancer and supplemented the effect mechanism of sortilin on pancreatic cancer cells. SEIN expression may serve as a potential diagnostic indicator of pancreatic cancer.
Risk Factors Associated with Development and Persistence of Long COVID: A Cross-Sectional Study
Authors: Miyazato Yusuke , Tsuzuki Shinya , Morioka Shinichiro , Terada Mari , Kutsuna Satoshi , Saito Sho , Shimanishi Yumiko , Takahashi Kozue , Sanada Mio , Akashi Masako , Kuge Chika , Osanai Yasuyo , Tanaka Keiko , Suzuki Michiyo , Hayakawa Kayoko , Ohmagari Norio
Published: November 2021

BackgroundLong coronavirus disease (COVID) has been a social concern. Though patient characteristics associated with the development of long COVID are partially known, those associated with its persistence have not been identified. MethodsWe conducted a cross-sectional questionnaire survey of patients after COVID-19 recovery who visited the National Center for Global Health and Medicine between February 2020 and March 2021. Demographic and clinical data and data regarding the presence and duration of long COVID were obtained. We identified factors associated with the development and persistence of long COVID using multivariate logistic and linear regression analysis, respectively. ResultsWe analyzed 457 of 526 responses (response rate, 86.9%). The median age was 47 years, and 378 patients (84.4%) had mild disease in the acute phase. The number of patients with any symptoms after 6 and 12 months after onset or diagnosis were 120 (26.3%) and 40 (8.8%), respectively. Women were at risk for development of fatigue (odds ratio [OR]: 2.03, 95% confidence interval [CI]: 1.31-3.14), dysosmia (OR: 1.91, 95% CI: 1.24-2.93), dysgeusia (OR: 1.56, 95% CI: 1.02-2.39), and hair loss (OR: 3.00, 95% CI: 1.77-5.09) and for persistence of any symptoms (coefficient: 38.0, 95% CI: 13.3-62.8). Younger age and low body mass index were risk factors for developing dysosmia (OR: 0.96, 95% CI: 0.94-0.98 and OR: 0.94, 95% CI: 0.89-0.99, respectively) and dysgeusia (OR: 0.98, 95% CI: 0.96-1.00 and OR: 0.93, 95% CI: 0.88-0.98, respectively). ConclusionWe identified risk factors for the development and persistence of long COVID. Many patients suffer from long-term residual symptoms, even in mild cases.
Natural History of Retinal Degeneration in Ovine Models of CLN5 and CLN6 Neuronal Ceroid Lipofuscinoses
Authors: Murray Samantha J , Mitchell Nadia L
Published: November 2021

Neuronal ceroid lipofuscinoses (NCL; Batten disease) are a group of inherited neurodegenerative diseases with a common set of symptoms including cognitive and motor decline and vision loss. Naturally occurring sheep models of CLN5 and CLN6 disease display the key clinical features of NCL, including a progressive loss of vision. We assessed retinal histology, inflammation, and lysosomal storage accumulation in CLN5 affected (CLN5−/−) and CLN6 affected (CLN6−/−) sheep eyes and age-matched controls at 3, 6, 12, and 18 months of age to determine the onset and progression of retinal pathology in NCL sheep. The retina of CLN5−/− sheep shows progressive atrophy of the outer retinal layers, widespread inflammation, and accumulation of lysosomal storage in retinal ganglion cells late in disease. In contrast, CLN6−/− retina shows significant atrophy of all retinal layers, progressive inflammation, and earlier accumulation of lysosomal storage. This study has highlighted the differential vulnerability of retinal layers and the time course of retinal atrophy in two distinct models of NCL disease. This data will be valuable in determining potential targets for ocular therapies and the optimal timing of these therapies for protection from retinal dysfunction and degeneration in NCL.
Exercise-induced hormone and blood fatigue factor responses to branched-chain amino acids administration in the recovery period after exercise: a systematic review and meta-analysis
Authors: Sefidari Azade , Rahimi Mohammad Hossein
Published: November 2021

Purpose: Branched-chain amino acid (BCAA) can boost anabolism through an increase in the internal concentration of BCAA, which leads to facilitating anabolic hormone release to stimulate the power of the muscles. Studies on administration of BCAA to minimize fatigue substances during long periods of high intensity exercise have been conducted. However, there are disagreements concerning the results of these studies.Method: A comprehensive search was performed on electronic databases up to November 2019 for trials evaluating the effects of BCAA on recovery following exercise. Mean ± standard deviation of follow-up cortisol, insulin, ammonia, and lactate concentrations were extracted to calculate the effect size for meta-analysis.Results: A total of 146 participants for cortisol and 279 participants for lactate were found from the 7 and 15 studies, respectively. The results revealed a significant effect of BCAA supplementation on cortisol concentration during 120≤ min post exercise follow-up. Moreover, without considering follow-up times, an overall analysis showed that BCAA was effective in reducing blood lactate in aerobic exercise and the trained status of athletes.Conclusions: The advantages of BCAA administration relate to a reduction in cortisol concentration after 2h and ameliorated muscle function because of a probable attenuation of fatigue substances immediately after exercise.
Pain, Depressive Symptoms, and Self-efficacy for Pain Management: Examination in Black Women With Breast Cancer
Authors: Vilardaga Jennifer Plumb , Fisher Hannah , Winger Joseph , Miller Shannon , Nunez Christine , Majestic Catherine , Kelleher Sarah , Somers Tamara
Published: November 2021

Purpose: Black women with breast cancer face significant disparities, including high levels of pain. Depressive symptoms and self-efficacy for pain management impact how women with breast cancer manage pain, yet little is known about how these variables relate to pain specifically for Black women with breast cancer. Methods: Baseline regression analyses were conducted using a sample of women (n=98) with stage I-III breast cancer identifying as Black or African-American who were part of a larger intervention trial. Model 1 explored depressive symptoms and pain (i.e., severity and interference). Model 2 explored self-efficacy for pain management and pain. Covariates were age (M=57.22,SD=10.76), cancer stage (50%=stage 1), and education level (36%=some college). Results: Participants reported moderate levels of pain severity and interference. Higher depressive symptoms were related to both higher pain severity and interference; (B=.06, p<.01, 95% CI [.02,.09], β=.32) and (B=.13, p<.001, 95% CI [.09, 17], β=.55) respectively. Likewise, lower self-efficacy for pain management was also related to both higher pain severity and interference; (B=-.04, p<.001, 95% CI [-.05,-.02], β=-.44) and (B=-.06, p<.001, 95% CI [-.08,-.04], β=-.53) respectively. Women reporting less than a high school diploma endorsed significantly higher pain severity and interference than women reporting some college. Age and cancer stage were not significantly related to pain.Conclusion: Pain for Black women with breast cancer may be influenced by depressive symptoms and self-efficacy for pain management, in addition to other important variables. Attending to better assessment and treatment of depressive symptoms and self-efficacy for pain management may improve outcomes.
Embankment Dam Design With Dispersive Soil: Solutions And Challenges
Authors: Salehi Davood , Heidari Ali
Published: November 2021

An embankment dam has been designed by using dispersive soil in East Africa after performing the required tests for dispersivity of the materials. Internal erosion through cracks or other openings in the embankment is the most concern of using the dispersive soils. The foundation of dam and borrow areas consist of dispersive soil and the effective measures has been considered in the design to safely deal with dispersivity according to recommendation of the codes and design guidelines. The selected solution was the combination of chimney filter, filter drain, and selective placement of materials in the dambody as the effective solution considering the specification of the project. The local instability in the contact zones was the concerns of designers and bilinear parameters has been considered in the stability analysis as the base case. This was due to the dispersive material and drain filter feature that determined according to nonlinear static and dynamic analysis of the dambody. This paper presents the measures and precautions that were taken into account in dealing with dispersive soil in order to ensure the safety of project.
Eco-Friendly Chitosan@Silver/Plant Fiber Membranes for Masks with Thermal Comfortability and Self-Sterilization
Authors: Zou Qian , Gai Yinuo , Gai Xiaotang , Xiong Siwei , Wei Nanjun , Jiang Mengying , Chen Liye , Liu Yang , Gai Jinggang
Published: November 2021

The surgical masks have been essential consumables for public in the COVID-19 pandemic. However, long-time wearing masks will make wearers feel uncomfortable and massive discarded non-biodegradable masks lead to a heavy burden on our environment. In this paper, we adopt degradable chitosan@silver (CS@Ag) core-shell fibers and plant fibers to prepare an eco-friendly mask with excellent thermal comfort, self-sterilization, and antiviral effects. The thermal network of CS@Ag core-shell fibers highly improves the in-plane thermal conductivity of masks, which is 4.45 times higher than that of commercial masks. Because of the electrical conductivity of Ag, the fabricated mask can be electrically heated to warm the wearer in a cold environment and disinfect COVID-19 facilely at room temperature. Meanwhile, the in-situ reduced silver nanoparticles (AgNPs) endow the mask with superior antibacterial properties. Therefore, this mask shows a great potential to address the urgent need for a thermally comfortable, antibacterial, antiviral, and eco-friendly mask.
Gauging Energy Poverty in Developing Countries through Electricity Access
Authors: Drago Carlo , Gatto Andrea
Published: November 2021

Energy poverty is a crucial development issue though is ambiguously conceived. In many parts of the world, energy poverty is a severe problem, particularly amongst the vulnerable and developing countries. When impoverished people do not have adequate access to energy, they will not be able to generate the power they need to lift themselves out of poverty and often get proper food, education, health and sanitation, infrastructures and basic daily and development needs. With the advantage of interval-based composite indicators and triplex representations of the intervals as a sensitivity analysis, we measure and assess developing countries’ electricity access as a proxy of energy poverty. The proposed quantitative approach is particularly innovative because it adequately gauges robust measures of electricity access and the level of resilience and vulnerability of energy access in the developing world. Our conclusion based on the comparison of the different representations allows identifying a cluster of developing countries showing higher international vulnerability, whilst other countries display higher electricity access resilience.JEL codes: C15 [Statistical Simulation Methods: Single Equation Models, Monte Carlo Methods, Bootstrap Methods] C43 [Index numbers and aggregations] I32 [Measurement and Analysis of Poverty] O13 [Agriculture, Natural Resources, Energy, Environment, Other primary products] Q01 [Sustainable development]