bluuebunny/crossref_metadata_2025 huggingface dataset:
Liquid-Liquid Equilibrium Studies of Carbon Dioxide/Bitumen System and Utilizing Ethyl Acetate as a Co-Solvent
Authors: Khan Mohammad Shah Faisal , Hassanzadeh Hassan
Published: May 2023

In situ bitumen extraction from oil sands using thermal recovery processes has faced challenges due to reliance on steam. Additionally, the produced bitumen is highly viscous and needs to be diluted with lighter hydrocarbon products, such as field condensates, for pipeline transportation. Therefore, exploring less energy-intensive options to produce and transport bitumen economically with less environmental impact is essential. This work aimed to study the liquid-liquid equilibrium (LLE) of CO2 and bitumen at ambient temperature. First, the impact of CO2 feed mass fraction and pressure on equilibrium mixture properties are investigated. In the next step, the effect of ethyl acetate (EA) as an additive on the equilibrium properties of the mixture is studied. The equilibrium properties of the mixtures, including CO2 solubility in the heavy liquid phase, the viscosity of the heavy liquid phase, and the densities of light and heavy liquid phases, are reported. The results suggest that the viscosity of bitumen is considerably reduced by mixing it with liquid CO2 at ambient temperature. It was also shown that the bitumen viscosity could be further reduced by the addition of ethyl acetate as a co-solvent.
A Robust Four-Phase Equilibrium Calculation Algorithm for Hydrocarbon-Water Mixtures at Pressure and Enthalpy Specifications
Authors: Li Sirui , Li Huazhou
Published: May 2023

A robust multiphase equilibrium calculation algorithm with pressure and enthalpy (PH) specifications, i.e., an isenthalpic algorithm, plays an important role in the compositional simulations of steam-based enhanced oil recovery (EOR) applications (such as steam and solvent co-injection process for heavy oil recovery). Up to now, there are few works documented in the literature focusing on four-phase isenthalpic algorithms. In this paper, we propose a four-phase isenthalpic algorithm with a nested approach. It contains an inner loop and an outer loop. In the inner loop, a well-designed isobaric/isothermal (PT) multiphase (up to four phases) equilibrium algorithm is employed to solve the phase fractions and compositions, while the Brent's method (1971) is applied in the outer loop to update the temperature by satisfying the energy conservation equation. We test the performance of the proposed algorithm using four case studies under different pressure-enthalpy conditions. Calculation results demonstrate that the proposed PH algorithm is always able to converge to the correct phase equilibria with only tens of PT algorithm calls.
Distributed Agent Optimization for Large-Scale Network Models
Authors: Nagao Masahiro , Sankaran Sathish , Guo Zhenyu
Published: May 2023

Optimization of production networks is key for managing efficient hydrocarbon production as part of closed-loop asset management. Large-scale surface network optimization is a challenging task that involves high nonlinearity with numerous constraints. In existing tools, the computational cost of solving the surface network optimization can exponentially increase with the size and complexities of the network using traditional approaches involving nonlinear programming methods. In this study, we accelerate the large-scale surface network optimization by using a distributed agent optimization algorithm called alternating direction method of multipliers (ADMM).

We develop and apply the ADMM algorithm for large-scale network optimization with over 1000 wells and interconnecting pipelines. In the ADMM framework, a large-scale network system is broken down into many small sub-network systems. Then, a smaller optimization problem is formulated for each sub-network. These sub-network optimization problems are solved in parallel using multiple computer cores so that the entire system optimization will be accelerated. A large-scale surface network involves many inequality and equality constraints, which are effectively handled by using augmented Lagrangian method to enhance the robustness of convergence quality. Additionally, proxy or hybrid models can also be used for pipe flow and pressure calculation for every network segment to further speed up the optimization.

The proposed ADMM optimization method is validated by several synthetic cases. We first apply the proposed method to surface network simulation problems of various sizes and complexities (configurations, fluid types, pressure regimes, etc.), where the pressure for all nodes and fluxes in all links will be calculated with a specified separator pressure and reservoir pressures. High accuracy was obtained from the ADMM framework compared with a commercial simulator. Next, the ADMM is applied to network optimization problems, where we optimize the pressure drop across a surface choke for every well to maximize oil production. In a large-scale network case with over 1000 wells, we achieve 2X – 3X speedups in computation time with reasonable accuracy from the ADMM framework compared with benchmarks. Finally, we apply the proposed method to a field case, and validate that the ADMM framework properly works for the actual field applications.

A novel framework for surface network optimization was developed using the distributed agent optimization algorithm. The proposed framework provides superior computational efficiency for large- scale network optimization problems compared with existing benchmark methods. It enables more efficient and frequent decision-making of large-scale petroleum field management to maximize the hydrocarbon production subject to numerous system constraints.
Effects of Axial Tension and Torque on Fatigue Performance of Threaded OCTG Connection
Authors: Lin Bisen , Bennett Frederick , Coe David , Pattillo Phillip
Published: May 2023

Casing strings, consisting of hundreds of ∼40 feet long pipe joints connected by threaded connections, usually experience axial tension and/or torsion when rotationally running through the build sections during casing installation of horizontal wells. It is important to understand the influence of axial tension and torsion on the connection's fatigue performance. In this paper, fatigue performance of threaded OCTG connections subjected to cyclic dogleg bending deformation is evaluated using fatigue crack growth methodology and full-scale connection fatigue testing.

Material constants in the fatigue crack growth model are first calibrated using a single set of full-scale connection fatigue test results on one connection. Several connection products (different combinations of connection design and size) are then analyzed using the calibrated fatigue model and compared to the full-scale fatigue-to-failure test results. Excellent agreement, in terms of both fatigue life and fatigue failure location, between the analysis and actual test results are observed.

Effects of connection torque and axial tension on fatigue performance are also investigated using the calibrated fatigue crack growth model for a broad range of connection products. For each connection analyzed, four different torques with values in-between the connection's minimum required makeup torque and yield torque are considered. Four different axial tension levels, equivalent to 0, 10, 20, and 30 ksi axial tensile stress of the corresponding pipe, are also analyzed. Overall, different connection torques or axial tensions do not impact the connection's fatigue performance significantly except for the small size (e.g. 4.500"pipe OD) T&C connections.
Prediction of Permeability from Logging Data Using Artificial Intelligence Neural Networks
Authors: Al-Otaibi Mohammed Abdullah , Abdullah Eassa , Hanafy Sherif Mahmoud
Published: May 2023

While many factors influence the success of a given well, the permeability of the surrounding formation is one of the most important properties to understand the nature of any reservoir and to be utilized for effective oil and gas drilling. Gathering data from well logs for different wells can be highly expensive and time-consuming. The goal of this work is to find the best artificial intelligent model which can predict the permeability values with minimum error while saving time and money. Therefore, accurately estimating is highly beneficial to use such a model for further field and engineering applications. In this project, a trial was accomplished through a Machine Learning (ML) approach using several modules of Artificial Intelligent including ANFIS and ANN to examine and build a permeability prediction model based on nine (9) well-logging parameters taken from well-logging data measured at a borehole in carbonate rock. The permeability was predicted from well-log data using Artificial Intelligent (AI) technique. Field data were recorded at one borehole, where all logs are correlated together. After obtaining results, the prediction model can be considered successful, it is highly recommended to utilize ANFIS- Genfis2 as it gives outstanding results as the correlation coefficient training was 1.0 and testing was 0.9347 compared with ANFIS-Genfis1 which was not satisfying with training correlation coefficient of 1.0 and testing 0.4073, including a significant reduction in the percentage error of 14.3% compared of 301%, and utilize ANN with a double layer not single, as the result of single layer showed a correlation coefficient of 0.9337 in training and 0.9924 in testing. In addition, single layer method showed higher error compared with double layer. Conclusively, it is recommended to apply the model with other data obtained from the same reservoir, to minimize the number of unneeded data, enhance the measurement performance by avoiding human errors, and develop other relationships between a set of parameters that can result in a better and most effective prediction model. In novelty, utilizing and studying the output of this trial application of the machine learning approach will summarize the best models and techniques for predicting many important reservoir properties such as Permeability. The number of well logging parameters is high and has been statically analyzed to increase the resolution of the input data. Building this prediction model will increase the recovered amount from the subsurface and will lead to significant cost savings in drilling and exploration operational
The Global Prevalence of Anxiety Symptoms Among Healthcare Workers Before and During COVID-19: A Systematic Review and Meta-analysis
Authors: Qing Chang , Yan Zixuan , Xia Yang , Su Han , Yan Shuai , Gao Yitao , Zhang Xi , Zhang Yixiao , Liu Caigang , Zhao Yuhong
Published: May 2023

Importance:The COVID-19 pandemic’s effect on the prevalence of anxiety symptoms among healthcare workers remains unclear. Hence, an investigation into their prevalence and the changes before and during the pandemic is needed.Objective:To provide a comprehensive summary of the prevalence of anxiety symptoms among healthcare workers internationally and to compare this before and during the COVID-19 pandemic.Data Sources:A literature search was conducted using Medline, PubMed databases, and Embase for observational studies from their establishment in January 1963, January 1963, and January 1989, respectively, to August 2022.Study Selection:A standardized search strategy was applied to the databases with keywords assembled into three categories, including “healthcare workers”, “anxiety symptoms”, and “miscellaneous”. The inclusion criteria were: (I) evaluation of the prevalence of anxiety symptoms among healthcare workers employed in hospitals; (II) measured through validation tools or questionnaires; (III) published in English. The exclusion criteria were: (I) no overall prevalence of anxiety provided; (II) case series, case reports, intervention research, and commentaries.Data Extraction and Synthesis:The protocol was developed based on the PRISMA guidelines. The pooled prevalence and 95% confidence interval (CI) were estimated using a random effects model.Main Outcome(s) and Measure(s):The articles were analyzed according to subgroups divided based on the time of the studies conducted, participant occupations, locations, screening instruments, and publication years.Results:A total of 358 cross-sectional articles with 373 estimates from 65 countries were included. The overall prevalence of anxiety symptoms among healthcare workers was 41.4% (95% CI, 39.3-43.4). The prevalence of anxiety symptoms before and during the COVID-19 pandemic were 40.7% (95% CI: 34.1-47.3) and 41.2% (95% CI: 39.1-43.3), respectively. Compared with studies before the pandemic, a higher prevalence of anxiety symptoms was identified among nurses, residents, and physicians during the pandemic.Conclusions and Relevance:A considerable proportion of healthcare workers have experienced anxiety symptoms, with their global prevalence increasing during the COVID-19 pandemic. Further research is needed to determine effective prevention and treatment strategies, particularly during the COVID-19 pandemic.Systematic review registration:CRD42022370819.
MSSRCA Powered Sensitive Point-of-Care Detection of HPV mRNA for Cervical Cancer Screening
Authors: Long Yi , Tao Shurui , Shi Dongni , Jiang Xingyu , Yu Tian , Long Yingxi , Song Libing , Liu Guozhen
Published: May 2023

Developing sensitive point-of-care testing (POCT) of oncogenic nucleic acids from HPV infection is essential in preventing cervical cancer, especially in resource-limited settings. Rolling circle amplification (RCA) is attractive in achieving POCT; however, still exists a bottleneck requiring multiple amplification steps with multiple detection probes due to the limited sensitivity. Here we developed a minimum secondary structured RCA technique (MSS-RCA) by designing a unique circular template, demonstrating significantly enhanced detection sensitivity with only one amplification step and one primer. We demonstrated that RCA amplification efficiency could be kinetically manipulated by controlling the secondary structure of the circular template. Introducing the invertase probe to MSS-RCA, Human Papillomavirus 16 (HPV16) E6/E7 nucleic acid target was detected with a personal glucose meter (PGM) with a sensitivity of 5 fM (50 zmol in 10 µL). This integrated MSS-RCA-PGM detection system was successfully applied to detect HPV16 E6/E7 mRNA extracted from 54 cervical swab samples reaching a positive predictive value of 100.00% and negative predictive values of 96.00% (77.77% to 99.40%, 95% CI). MSS-RCA-PGM provides a sensitive POCT platform for the detection of biomarkers for screening of cervical cancer or other diseases.
Enhancing Tendon Regeneration: Investigating the Impact of Topography on the Secretome of Adipose-Derived Stem Cells
Authors: Long Qiuzi , Zhang Wei , Liu Chuanquan , Zheng Haotian , Wang Mingyue , Cao Zhicheng , Sun Yuzhi , Mo Qingyun , Backman Ludvig J. , Huang Jinlong , Chen Jialin
Published: May 2023

Background: Tendons are vital for maintaining integrity and movement, but current treatment options are insufficient for restoring them after injuries. Previous studies have shown that the secretome from mesenchymal stem cells (MSCs) promoted tendon regeneration. However, limited studies have explored the impact of the cellular microenvironment on the secretome of MSCs in tendon repair. This study aims to investigate how the topographic orientation impacts the secretome of human adipose-derived stem cells (ADSCs) and its effect on tendon repair and regeneration.
Methods: Randomly oriented and aligned silk scaffolds were prepared by directional freeze-drying. Conditioned medium (CM) was generated from ADSCs cultured on the scaffolds with different topography (RCM: random scaffolds; ACM: aligned scaffolds). In vitro experiments were performed to access the effect of RCM and ACM on cell proliferation by live/dead staining, CCK-8 incubation, and Ki67 immunofluorescence. The effect on tenogenic differentiation of tendon stem/progenitor cells (TSPCs) and polarization of macrophages was confirmed by detecting the expression of related genes. Subsequently, RCM and ACM were injected into rats with patellar tendon defects. Tissue repair and immunomodulatory effects were evaluated through histological and immunohistochemical staining.
Result: In vitro results showed that the ACM group had a more potent effect in promoting the proliferation of TSPCs as compared to RCM group. ACM group promoted tenogenic differentiation of TSPCs, as evidenced by higher expression of SCX, TNMD, and MKX in contrast to RCM. In addition, ACM group up-regulated the expression of M2-related anti-inflammatory genes including ARG-1 and IL-10, and down-regulated M1-related inflammatory genes including CCR7, iNOS, and IL-1β in RAW 264.7 cells, as compared to RCM group. The ACM group exhibited a greater formation of tendon-like tissues, as confirmed by histological evaluation, and a higher expression of tendon-related specific proteins, including SCX, TNMD, and COL I as shown by immunohistochemistry as compared to RCM group. The tissue sections of the ACM group showed a high expression of the M2 anti-inflammatory polarity-related protein ARG-1, and a low expression of the M1 pro-inflammatory polarity-related protein iNOS. These results were consistent with the in vitro findings.
Conclusions: This study highlights the topographical dependency of ADSCs paracrine activities and demonstrates the potential of using oriented silk scaffolds to enhance the ADSCs secretome for tendon regeneration. These findings offer a promising, safer, and non-cell-based treatment option for tissue regeneration.
Preparation of ZIF-67/C3N4 composite material and adsorption of tetracycline hydrochloride
Authors: zhang mingyuan , Li Yueyao , Zhou Xiaoying , Wang Liping , Xie Yuke , Hou Chentao
Published: May 2023

In recent years, wastewater treatment to remove tetracycline hydrochloride (TCH), has received much attention in water treatment problems. ZIF-67/C3N4 composite adsorbent, a nanosheet structured material stacked with MOFs, was prepared by in situ growth method, which has high adsorption activity for tetracycline hydrochloride in wastewater. Comparing the effect of monomeric and composite adsorbents, Z6C2 had the best adsorption effect (206 mg·g− 1), which was 77.6% higher than that of ZIF-67 (116 mg·g− 1) and 10.8 times higher than that of C3N4 (19 mg·g− 1).The structure of ZIF-67 stacked on C3N4 nanosheets has an excellent specific surface area and number of active sites, as well as π-π interactions, electrostatic interactions and hydrogen bonding interactions between the adsorbent and TCH, which combine to enhance the adsorption performance. The adsorption process is accompanied by a combination of chemisorption, mass transport and internal diffusion rate-limiting. The adsorbent exhibits good stability and adsorption capacity, which may be suitable for efficient and low-cost water purification.
Reliability and validity of a questionnaire measuring knowledge, attitude and practice regarding “oil, salt and sugar” among canteen employees in China
Authors: Mo Zhenhan , Li Xiaofan , Zhai Yuting , Men Yanyan , Tang Yuying , Qiao Jiarui , Jia Xue , Huang Yujie , Wang Baozhen
Published: May 2023

Background Excessive intake of oil, salt and sugar is closely associated with the prevalence of NCDs. Canteen employees’ knowledge, attitude and practice (KAP) about oil, salt and sugar directly affect the content of them in dishes and the consumers’ intake. However, there is no valid questionnaire used to assess KAP among canteen employees about the “oil, salt and sugar”. Therefore, the aim of the present study was to establish and validate a questionnaire to evaluate the KAP of canteen employees about the “oil, salt and sugar”.Methods A total of 100 canteen employees randomly selected from three different college canteens in Shandong Province. Participants completed the questionnaire and retested 1 month later. Internal reliability and test-retest reliability were assessed using Cronbach’s α and Pearson correlation coefficients, respectively. Validity was assessed using the exploratory factor analysis.Results The final questionnaire consisted of four sections, 76 items: demography (13 items), knowledge (21 items), attitude (20 items), and practice (23 items). A total of 100 participants finished the questionnaire of which 66% were females with a mean age of 40.3 years. The Cronbach’s α coefficients of the questionnaire and each dimension were 0.822, 0.830, 0.752 and 0.700, respectively. The test-retest reliability coefficient is 0.968; In exploratory factor analysis, 9 common factors are extracted, with a total of 26 items, and the cumulative contribution rate is 70.923%.Conclusion The questionnaire had a satisfactory property for measuring the KAP of the “oil, salt and sugar” among canteen employees in China.
Unusual masquerading infraorbital mass – First case report of human ocular Dirofilariasis found in an Ukrainian patient in Switzerland
Authors: Menna Feliciana , Billia Filippo , Papazoglou Anthia , Tschopp Markus , Grobholz Rainer
Published: May 2023

A 78-year-old Ukrainian woman immigrated to Switzerland presented with a rapid growing subcutaneous infraorbital mass. Surgical excision of the mass revealed a well-circumscribed, encapsulated tumor, adherent to the skin. The excision showed a soft tissue inflammation with parts of helminthozoonosis diagnosed as Dirofilaria repens. The number of cases of human Dirofilariasis reported in the last 50 years has gradually increased. Dirofilaria repens is now endemic in many countries and is currently considered to be one of the fast spreading zoonoses in Central, Eastern and Northern Europe. The first empirical evidence of Swiss spreading of Dirofilaria infections was in a dog from southern Switzerland in 1998. Ours is the first case of human orbital Dirofilariasis reported in Switzerland. Our purpose is to inform the ophthalmologist to consider orbital dirofilariasis in the differential diagnosis of inflammatory masses of the orbit and to warn about the spread of this infection in Switzerland.
Frequency lock-in control and mitigation of vortex-induced vibrations of an airfoil using a conserved-mass nonlinear vibration absorber
Authors: Basta Ehab , Gupta Sunit K. , Barry Oumar R
Published: May 2023

We investigate the effectiveness of a vibration absorber on the vortex-induced vibration response of turbine blades during the frequency lock-in phase. A reduced order model is considered for a turbine blade and a von der Pol oscillator is used to model fluid blade interaction caused by the vertex shedding. A spring-mass-damper system is considered to model the vibration absorber. The advantage of the vibration absorber is demonstrated by simulating the nonlinear coupled fourdegree-of-freedom aeroelastic system for the different sets of system parameters. We observe the dominance of a nonlinear vibration absorber over the linear vibration absorber only for the higher coupling parameter values. The analytical solution of the nonlinear coupled system is obtained through the method of multiple scales for the case of 1:1 internal resonance to identify the critical design parameters of the vibration absorber. We observe the high sensitivity of the system's frequency response towards the distance of the vibration absorber from the elastic axis, along with the absorber's damping, stiffness, and mass. Finally, we perform a parametric analysis on the lockin the stability region to better understand the effect of the vibration absorber on the instability region.
Prediction of groundwater levels by 2100 considering climate change based on precipitation and river stage
Authors: Kim Bokyung , Nam Donggun , Lee Junhwan
Published: May 2023

Changes in GWL is an important consideration for establishing sustainable social infra system and disaster prevention. In this study, methodology for predicting future GWL is established based on the climate change scenario and adopted to predict GWL by year 2100. Deep neural network (DNN) and engineering groundwater level prediction model (EGPM) were adopted for precipitation- and river stage-dominant cases. Database of hydrological and geographical parameters was established and introduced into the prediction. It was shown that present and future GWLs were not the same, and the difference was most noticeable in near-river area. The increases in GWL by 2100 in Magok region was estimated around 1.8 m. The GWL in Jangwi and Hangdong regions indicated an increase around 0.18 m, implying that the increase in GWL would not be dramatically large, yet gradual increase is anticipated. All these indicated a tendency of higher GWL in future with magnitude depending on regional and locational conditions of target area. Predicted future GWL profiles were introduced into the 3D flow analysis program MODFLOW to establish a visual utilization of predicted GWL.
Elman neural network and equivalent circuit model based multi-measurement Kalman filters for SOC estimation
Authors: Shen Dezhi , Ding Jie , Hao Tianyun
Published: May 2023

This paper provides an insight into the estimation of state of charge (SOC) of lithium-ion batteries, and multi-measurement Kalman filters are constructed to achieve better estimation accuracy. The filter based estimation scheme consists of two sub Kalman filters, one based on the Thevenin equivalent circuit model and the other based on the Elman neural network model. They share the same state equation but have different measurements, namely from the terminal voltage and the Elman neural network, respectively. The optimal weighted error covariance matrix in Kalman filter is computed to obtain the final estimated SOC with the results from two sub filters. The training set of the experiment is from five mixed charging and discharging cycles and the test set is the LA92 driving cycle. The experimental results show that multi-measurement Kalman filtering has higher accuracy in SOC estimation, both the mean absolute error and the root mean square error are less than 0.3\%.
Research on Path Planning of UAV Swarm for Decapitation Strike
Authors: Zhang Zhihao , liu xiaodong , Feng Boyu
Published: May 2023

Decapitation strike is an important part of modern war, which could achieve significant effect at a small cost. With the rapid improvement of unmanned aerial vehicle (UAV) swarm's ability to carry out reconnaissance and strike missions, this combat mission can be performed by UAV swarm instead of ground special forces or fighters. Based on the analysis of mission profiling, this article establishes the mission model and threat area model of decapitation strike. Then, combining Bézier curve with receding planning framework, an Optimized model for UAV swarm path planning under the condition of full coverage antiaircraft firepower is proposed. The simulation results show that the model and improved algorithm in this paper can effectively solve the path planning problem of UAV swarm in the face of full coverage threat. The research can make up for the defects of the traditional "Cross Gaps" path planning algorithm in solving the problem of crossing threat areas, and provide effective guidance for UAV swarm to perform the decapitation missions.
The gut microbiota mediates triptolide-induced liver injury via the gut-liver axis
Authors: Wang Yulin , Hu Yeqing , Liu Yuting , Zhang Haibo , Liu Xueying , Zhou Hua , Liu Chenghai , Yang Tao
Published: May 2023

Triptolide (TP) is a toxic component of Tripterygium wilfordii Hook. f. that exhibits liver and gastrointestinal toxicity. However, TP-induced liver injury varies between individuals via an unknown mechanism, which limits the safe clinical application of TP. Herein, we aimed to study the mechanism underlying the regulation of TP-induced liver injury via the gut-liver axis using a multi-omics technique. C57BL/6 mice were administered with TP at 800 µg/kg. We also constructed a mouse model based on the male C57BL/6 gut microbiota with quadruple antibiotics. 16S rRNA gene sequencing, hematoxylin and eosin staining, and biochemical analyses were used to analyze the intestinal microbiota composition in stool samples and TP-induced hepatotoxicity and enterotoxicity. Proteomics and targeted metabonomics were performed to analyze key proteins related to intestinal injury and differential liver metabolic markers. Gut microbiota Lactobacillus and Bacteroides were related to TP hepatotoxicity, while the Lactobacillus rhamnosus or Bacteroides fragilis colonization alleviated TP-induced liver and ileum damage after gut microbiota disorder. Multi-omics analyses showed that the TP caused changes in genes related to intestinal and liver immune responses. Gut microbiota disorder amplified related immune responses, causing changes in intestinal immune barrier-related proteins REG3B and REG3G and changes to liver metabolites via the gut-liver axis. Thus, the gut microbiota (via the gut–liver axis) plays an important role in liver injury induced by TP, allowing a better interpretation of TP-induced hepatotoxicity.
The Relationship between AQP1 Expression and Severity of Hydrocephalus in Rattus Norvegicus Strain Sprague-Dawley Rats
Authors: Januarman Januarman , Parenrengi Muhammad Arifin , Suryaningtyas Wihasto , Utomo Budi , Bajamal Abdul Hafid , Subagio Eko Agus
Published: May 2023

Purpose: We evaluate the relationship between the severity of hydrocephalus and AQP­1 levels.
Methods: This research was conducted in an experimental research design. The research subjects were Rattus Norvegicus rats of the Sprague-Dawley strain which were injected with kaolin to create a hydrocephalus model. The study included 24 rats in total, which were divided into four groups of six each: the control group, and the hydrocephalus induction group on day 7, day 14, and day 21. AQP1 expression was then observed histopathologically by immunohistochemical staining and counted semi-quantitatively. The collected data were then compared and analyzed using SPSS software version 24.
Results: The average AQP1 expression increased with observation time in the hydrocephalus rat model on the 7th, 14th, and 21st days. The ANOVA test showed a significant difference between the four study groups (p=0.001). The correlation between the expression of AQP1 levels and the severity of hydrocephalus showed a statistically significant difference (p=0.000). The results showed an increase in the expression of AQP1 levels in the sub-ventricle zone with the higher severity of hydrocephalus.
Conclusion: The severity of hydrocephalus and AQP1 levels are correlated, with the latter being higher the more severe the degree of hydrocephalus.
Immune-related Signature of Periodontitis and Alzheimer’s disease linkage
Authors: Jin Jieqi , Guang Mengkai , Li Simin , Yan Xing , Liu Yong , Zhang Liwei , Zhang Bo , Cheng Menglin , Schmalz Gerhard , Huang Xiaofeng
Published: May 2023

Background Periodontits (PD) and Alzheimer’s disease (AD) are both associated with ageing and clinical studies increasingly evidence their association. However, specific mechanisms underlying this association remain undeciphered, and immune-related processes are purported to play a signifcant role. The accrual of publically available transcriptomic datasets permits secondary analysis and the application of data-mining and bioinformatic tools for biological discovery.Aim The present study aimed to leverage publically available transcriptomic datasets and databases, and apply a series of bioinformatic analysis to identify a robust signature of immune-related signature of PD and AD linkage.Methods We downloaded gene-expresssion data pertaining PD and AD and identified crosstalk genes. We constructed a protein-protein network analysis, applied immune cell enrichment analysis, and predicted crosstalk immune-related genes and infiltrating immune cells. Next, we applied consisent cluster analysis and performed immune cell bias analysis, followed by LASSO regression to select biomarker immune-related genes.Results The results showed a 3 gene set comprising of DUSP14, F13A1 and SELE as a robust immune-related signature. Macrophages M2 and NKT, B-cells, CD4 + memory T-cells and CD8 + naive T-cells emerged as key immune cells linking PD with AD.Conclusion Candidate immune-related biomarker genes and immune cells central to the assocation of PD with AD were identified, and merit investigation in experimental and clinical research.
Beyond the five possibilities: Why was the international research in Darfur not submitted for ethical approval? A qualitative study
Authors: Hussein Ghaiath , Elmusharaf Khalifa
Published: May 2023

Background We have conducted a systematic review of the eligible reports of the studies conducted in the war-roubles regions of Darfur, west Sudan between 2004 and 2012 and reported on the proportions of the studies that reported gaining ethical approval. The proportion of studies reporting ethical review was smaller than might be expected, so we suggest five explanations for these findings.Objective To examine whether the five possibilities we suggested in the previous review were a fair representation of the reasons why these studies did not report having ethical approval.Methods A qualitative case study was used that involved conducting interviews and focus groups with the relevant stakeholders, namely the representatives of the national and international non-governmental organizations, UN agencies, and the national humanitarian and research governance bodies in Sudan.Results 38 participants were involved (5 interviewees and 33 participants in the focus groups). The participants expressed a consensus on the need for an ethical oversight for research in the humanitarian settings in Sudan and particularly Darfur. However, there were eight reasons for not submitting the humanitarian research to ethical approval, which we are categorized under four main themes: I) lack consistency in defining research, II) time-related arguments and the low-risk nature of their studies, III) previous explicit or implied approval of the study or its used tools and IV) lack of awareness about or intention to apply for ethical review.Discussion We presented these themes and discussed both sides of each argument.Conclusion There is a need to revisit the mainstream ethical review governance mechanisms to meet the requirements of the humanitarian settings. Methodologically, this project provided additional insights and a model of how the qualitative methods can be used to complement our understanding of the quantitative data resulting from the systematic review alone.
Geopolymers based on Metakaolin reinforced with Carbon Nanotubes
Authors: Brandão Daniele , Borges Paulo H. R. , Ludvig Peter , Colão Michelle
Published: May 2023

Geopolymers offer an alternative to Portland cement, boasting high mechanical strength, as well as chemical and thermal durability. It is an inorganic polymer that has environmental advantages in its production, in addition to being considered a high-performance material. This study seeks to evaluate the mechanical properties of geopolymeric mortars reinforced with Carbon Nanotubes (CNT) as well as the method of incorporation into the mortar. CNTs are promising materials as reinforcements in geopolymeric matrices for the development of construction materials with specific applications aimed at better performance. The studied matrix results from the alkaline activation of metakaolin (MK) with sodium silicate and sodium hydroxide. CNTs were added in percentages of 0.1%, 0.3%, and 0.5% by mass of metakaolin. The evaluated properties for the resulting composite were compressive strength and flexural strength. Scanning Electron Microscopy (SEM) and Infrared Spectroscopy (FTIR) tests were carried out to evaluate the dispersion of CNTs in MK (before activation). The results show that when well distributed in the matrix, CNTs promote an increase in compressive and flexural strength of the samples.
Bacillus altitudinis 1.4 genome analysis - functional annotation of probiotic properties and immunomodulatory activity
Authors: Jankoski Priscila Ribeiro , Bach Evelise , Fonseca Renata Nobre , Hübner Silvia , Carvalho Joseane Biso , Motta Amanda Souza da
Published: May 2023

Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. They are often used to improve intestinal health. In this study, phenotypic and genotypic methods were used to evaluate the probiotic properties of Bacillus altitudinis 1.4. The isolate was sensitive to all tested antimicrobials and showed a positive result in the hemolysis test. The results also indicated that the spores of B. altitudinis 1.4 were more resistant than the vegetative cells, when evaluated in a simulation of cell viability in the gastrointestinal tract, as well as adhesion to the intestinal mucosa. The isolate was able to self-aggregate and coaggregate with pathogens such as Escherichia coli ATCC 25922 and Salmonella Enteritidis ATCC 13076. Genomic analysis revealed the presence of genes with probiotic characteristics, such as fglA-L, motA, motB, luxS, pgaA-D, exoX, epsG. From this study, it was possible to evaluate the gene expression of pro-inflammatory and anti-inflammatory cytokines for different treatments. Viable vegetative cells of B. altitudinis 1.4 increased the transcription of pro-inflammatory factors, such as TNFα, NFkβ, TLR2, in addition to also increasing the transcription of IL-10, indicating a tendency to stimulate a pro-inflammatory profile. In view of the results presented, B. altitudinis 1.4 showed the potential to be applied in the incorporation of this microorganism in animal feed, since the spores could tolerate the handling and pelleting processes of the feed.
Economic Analysis of Wind Turbines in Oil and Gas Platforms: A Case Study
Authors: Yousefpour Khalegh , Abdalisousan Ashkan
Published: May 2023

Diesel generators or gas turbines located in the platforms usually do electricity production in oil and gas platforms. Using the above equipment, taking into account safety issues to prevent explosions and fires, as well as fueling them offshore, will be very expensive. In addition, the mentioned devices emit a significant amount of CO2 and NOx. Therefore, the use of renewable energy instead of fossil fuels can be much more economical and environmentally friendly. This study attempts to investigate the potential of using wind energy in the Persian Gulf and the feasibility and detailed economic analysis of using wind turbines on oil and gas platforms to provide part of the energy required. For this purpose, wind speed data are extracted from measurements at 10 meters, 30 meters and 40 meters above the ground. Average wind speed for the mentioned levels as 4.45 m/s, 4.99 m/s and 5.34 m/s respectively. In addition, it gives the annual power density as 128.36 W/m2, 173.80 W/m2 and 210.42 W/m2. The results obtained by using RETScreen software show that in this project with a life span of 30 years, the economic output of wind turbine systems is profitable, so that after 8.2 years, the entire cost of the project will return.
Challenges to the implementation of a multi-level intervention to reduce mistreatment of women during childbirth in Iran: a qualitative study using the consolidated framework for implementation research
Authors: Mirzania Marjan , Shakibazadeh Elham , Babaey Farah , Hantoushzadeh Sedigheh , Khajavi Abdoljavad , Foroushani Abbas Rahimi
Published: May 2023

Background: Mistreatment during childbirth is a growing concern worldwide, especially in developing countries such as Iran. In response, we launched a comprehensive implementation research (IR) project to reduce mistreatment during childbirth and enhance positive birth experience in the birth facilities. In this study, we identified the challenges of implementing a multi-level intervention to reduce mistreatment of women during childbirth using the consolidated framework for implementation research (CFIR).
Methods: An exploratory qualitative study involving thirty in-depth and semi-structured interviews was conducted between July 2022 and February 2023. Participants include a purposive sample of key informants at different levels of the health system (macro: Ministry of Health and Medical Education; meso: universities of medical sciences and health services; and micro: hospitals) with sufficient knowledge, direct experience and/or collaboration in the implementation of the studied interventions. Interviews were transcribed verbatim and coded using directed qualitative content analysis (CFIR constructs) in MAXQDA 18.
Results: The identified challenges were: (1) Individual level (childbirth preparation classes: e.g., adaptability, design quality and packaging, cosmopolitanism; presence of birth companion: e.g., patient needs and resources, structural characteristics, culture); (2) Healthcare provider level (integrating respectful maternity care into in-service training: e.g., relative priority, access to knowledge and information, reflecting and evaluating); (3) Hospital level (evaluating the performance of maternity healthcare providers: e.g., external policies and incentives, executing); and (4) National health system level (implementation of painless childbirth guidelines: e.g., networks and communications, knowledge and beliefs about the intervention, executing, reflecting and evaluating).
Conclusions: This study shows a clear understanding of the challenges of implementing a multi-level intervention to reduce mistreatment of women during childbirth; and highlights potential implications for policy makers and practitioners of maternal health programs. We encourage them to take the lessons learned from this study and revise in the implementation of their current programs and policies regarding the quality of maternity care by focusing on identified challenges.
Stakeholder Engagement in the Development of an Upper Extremity Outcome Measure for Children with Rare Musculoskeletal Conditions
Authors: Elfassy Caroline , Wagner Lisa , Higgins Johanne , Montpetit Kathleen , Snider Laurie , Dahan-Oliel Noemi
Published: May 2023

Background Individuals with arthrogryposis multiplex congenita (AMC) have upper extremity (UE) involvement in 73% of cases, yet no AMC specific outcome measure exists. When developing a measure specific to a population with a rare musculoskeletal condition, clinicians’ and patients’ perspectives and involvement is a crucial and necessary step. Therefore, this study determines the most clinically useful items for an outcome measures of UE function for children with AMC as defined by caregivers and clinicians.Methods To ensure the perspectives and needs of caregivers of children with AMC and clinicians were considered in the development of the UE measure for AMC, a Nominal Group technique (NGT) with caregivers of children with AMC (phase 1) followed by a three-round survey with clinicians (phase 2) were carried out.Results Phase 1: Eleven individuals participated in the nominal group technique and identified 32 items. The most important items were Picking up an object (n = 11), Eating (n = 10), Reaching mouth (n = 10), Getting out of bed (n = 10). Phase 2: Invitations to participate to an online survey was sent to 47 experts in the field of AMC, 20 participants completed round 1, 15 completed round 2 and 13 completed round 3. Throughout the survey, participants were asked about movement required to screen the UE, essential domains to be included in the measure, establishing a scoring guide and identifying tasks associated with joint motion and position.Conclusion A preliminary version of an UE AMC-specific outcome measure was developed with the help of caregivers’ perspectives and expert opinions.
Development of a biomarker signature associated with anoikis to predict prognosis and immunotherapy response in melanoma
Authors: Wu Zhixuan , Bao Jingxia , yin Mengqi
Published: May 2023

Background: Skin cutaneous melanoma (SKCM) is malignant cancer known for its high aggressiveness and unfavorable prognosis, particularly in advanced tumors. Anoikisis a specific pattern of programmed cell death associated with tumor regeneration, migration, and metastasis. Nevertheless, limited research has been conducted to investigate the function of anoikis in SKCM.
Methods:Anoikis-related genes (ARGs) were extracted from Genecards to identify SKCM subtypes and to explore the immune microenvironment between the different subtypes. Prognostic models of SKCM were developed by LASSO COX regression analysis. Subsequently, the predictive value of risk scores in SKCM and the association with immunotherapy were further explored. Finally, the expression of 6 ARGs involved in the model construction was detected by immunohistochemistry and PCR.
Results: This study identified 20 ARGs significantly associated with SKCM prognosis and performed disease subtype analysis of samples based on these genes, different subtypes exhibited significantly different clinical features and tumor immune microenvironment (TIME) landscapes. The risk score prognostic model was generated by further screening and identification of the six ARGs. The model exhibited a high degree of sensitivity and specificity to predict the prognosis of individuals with SKCM. These high- and low-risk populations showed different immune statuses and drug sensitivity. Further immunohistochemical and PCR experiments identified significant differential expression of the six ARGs in tumor and normal samples.
Conclusion: Anoikis-based features may serve as novel prognostic biomarkers for SKCM and may provide important new insights for survival prediction and individualized treatment development.
Human Parvovirus B19 Infections among Blood Donors in Selected Blood Centers in Ghana
Authors: Antwi-Baffour Samuel , Mensah Benjamin Tetteh , Awuni Lydia Kintampo , Armah Dorinda Naa Okailey , Annison Lawrence
Published: May 2023

Background Blood transfusion is an invaluable human resource and lifesaving therapy in hospital practice for patients, but it is bereft with possible transmission of infection such as Human Parvovirus B19. Human Parvovirus B19 is the only member of the Parvoviridae family known to be pathogenic to humans. Infections of Parvovirus B19 occur all year round and can affect all age groups even though a number of the patients show subclinical manifestations. The aim of this research was to determine the sero-prevalence of Human Parvovirus B19 infections among blood donors at selected blood centers in Ghana.Methods The research was a cross-sectional study carried out among blood donors at the selected blood banks. Blood samples were collected from the participants and screened for both IgG and IgM antibodies to Human Parvovirus B19 using ELISA Kits to establish the sero prevalence of the virus among the blood donors. Risk factors associated with the spread of the infections were also determined.Results A total of 167 participants took part in the study and majority of them were males (93.7%) and about70.7% of them were between the ages of 30 to 39 years. At the end of the sample analysis, 10 (5.9%) of the participants tested positive for IgM antibodies (Reactive), indicating active infections whilst 108 (64.7%) were reactive for IgG antibodies, representing those that have been exposed to the virus before. Though none of the study participants have had any blood transfusion before, about 47.3% had however donated blood before. From the demographics data gathered, the study also showed that none of the participants had multiple sex partners, used drugs, smoked or shared needles but about 22.8% had however received hepatitis B vaccination.Conclusion The outcome of the study showed that more than 50% of participants were reactive to the IgG antibodies indicating previous exposure to the virus and 5.9% were reactive to the IgM antibodies an indicator of current and active infection. These findings indicate that it may be very important to include Parvovirus screening in the procedure for blood donation in order to make blood transfusion therapy a safe process.