bluuebunny/crossref_metadata_2025 huggingface dataset:
Recent Advances in Downhole Fiber Optics Modeling & Analytics: Case Studies
Authors: Bale Derek S , Satti Rajani P , Failla Roberto , Harper Jason , Raggio John
Published: November 2020

In recent years, the upstream oil and gas industry has witnessed significant breakthroughs in developing and deploying permanent, on-demand, and distributed temperature (DTS) and acoustic (DAS) fiber-optic monitoring systems to optimize well completions and enhance production. Beyond steady advances in hardware, challenges associated with the analysis of distributed optical data are being addressed to enable delivery of value-driven answer solutions and services. Such solutions are often nontrivial and must be driven by scientific workflows in which data-driven models, advanced analytics and most importantly, physics-based models are applied at the right scale to correlate the data to downhole events.

In this study, we present a methodology for integrating state-of-the-art intelligent completion and production tools together with a robust modeling and analytics framework for the efficient development of data interpretation services for complex downhole environments. The answer product platform discussed is built on fast computational models, robust data-driven analytics, cloud-based data streaming and management services, and real-time reporting delivery systems. Several case-studies demonstrate how our fiber-optics solutions and analysis are leveraged for applications such as leak detection, fluid injection profiling, acid placement, sand detection, and water ingress. For each case-history, we discuss the operational workflow for the downhole intelligent assembly, procedures for acquiring high-resolution DTS/DAS data, and the use of advanced fast physics or data driven models used to deliver the solution. Some of the application examples (e.g. water ingress and sand detection) also demonstrate how simultaneous measurements of DTS and DAS data are often critical to detecting and devising a strategy for mitigating well-specific issues.

The case-studies presented in this study demonstrate how vast amounts of data can be acquired by fiber-optic interrogation systems and subsequently interpreted in real-time, or near real-time. Such a process is enabling oil and gas operators to make data-driven decisions that drive optimized reservoir performance and proactively mitigate operational risk such as NPT due to equipment failure.
Revolutionary Products and Materials from Heavy Oil that Producers, Investors, Consumers and Regulators Should Know About
Authors: Elias Ramon , Medizade Mason M. , Zhang Shanju , Elias Stephen R.
Published: November 2020

New technology and energy production have been fundamental staples for improving our quality of life, creating jobs and expanding a vibrant U.S. and global economy. Fossil resources like crude oil and natural gas have been essential for accomplishing this. Main uses have been to fuel the production of electricity, generate heat for our comfort and manufacturing, and supply energy for transportation. Petroleum and natural gas also produce many important precursors for a multitude of products and materials that also have transformed our world. Lesser known is that our need for these materials is growing faster than our need for fuel.

An emerging demand for precursors used to produce carbon-based substances like carbon fiber, carbon nanotubes and graphene is one reason why. These materials are composed entirely of carbon. Resources containing high amounts of carbon are needed for their production. Crude oil and natural gas are well suited for that purpose and we show that a new era of uses for these important resources is evolving.

Why the interest in carbon-based materials? They are very strong, very light, and have a wide range of uncommon and extraordinary physical properties. The synthesis of these materials is rapidly gaining importance as one of the most exciting and promising innovations ever developed by man. While various sources for producing carbon-based materials have been identified, petroleum or crude oil is proving to be both suitable and preferred.

In this review paper, we (i) give examples of the numerous incredible new carbon-based products and materials that are advancing and growing, (ii) briefly discuss known processes used to make the needed material precursors from petroleum, (iii) show evidence that refinery yields are shifting from fuels to materials, and (iv) cite exciting and forward looking research programs now underway. Also discussed is why lower API gravity, or higher density petroleum known as heavy oil, could be a preferred source of carbon-based material precursors. The discussion that follows gives ample reason to step back and reassess the views expressed by some on the continued importance of fossil resources and their emerging new uses in today's world.
Synergistic Surfactant Blends for Wettability Alteration in Wolfcamp and Eagle Ford Shale for Improved Oil Recovery
Authors: Singh Robin , Miller Joseph
Published: November 2020

The goal of this work is to develop synergistic surfactant blends that can perform wettability alteration for improved oil recovery (IOR) in tight liquid-rich unconventional shale reservoirs. Shales samples from Eagle Ford and Wolfcamp formation were used in this study. The performance of these surfactant systems in altering the wettability and improving the spontaneous imbibition process was evaluated. Comprehensive screening of surfactants (anionic, non-ionic, zwitterionic) was performed in this study. First, aqueous stability tests of these surfactant systems were performed at reservoir temperature. Second, contact angle experiments were conducted on polished oil-wet shale (Eagle Ford and Wolfcamp) chips to screen formulations with optimal wettability-altering capabilities. Third, bulk emulsion stability was investigated by measuring the half-lives of the emulsions. Fourth, the interfacial tensions between oil-surfactant formulations were measured via the pendant drop method using a goniometer. Finally, spontaneous imbibition experiments in tight cores such as carbonates and shale were performed to evaluate the efficacy of these formulations in recovering oil.

Several anionic surfactants and their blends with anionic, non-ionic, and zwitterionic cosurfactants were shortlisted based on the aqueous stability tests. Polished shale chips from Eagle Ford and Wolfcamp formation were made oil-wet by aging them with crude oil at 85 °C for 30 days. Contact angle experiments revealed that these synergistic surfactant blends can alter the wettability from oil-wet to water-wet conditions and outperform the performance of the individual surfactant system. The spontaneous imbibition experiments demonstrate that a significant amount of oil (11.8 to 52 % OOIP) can be recovered from tight carbonate rocks by optimally selecting surfactant formulations. It was shown that surfactant imbibition in an originally oil-wet shale sample can recover a significant amount of oil (12.96 to 22.4% OOIP). Unconventional liquid-rich shale plays such as Eagle Ford, Bakken and Wolfcamp constitute a major portion of the oil production in the US. Surfactants can significantly improve production from such shales and improve oil recovery. This study offers a novel systematic investigation of synergistic surfactant blends which alters the wettability of oil-wet shale to water-wet and induce spontaneous imbibition in liquid-rich shales to increase oil recovery.
Dynamic Simulation of Electrical Submersible Pump ESP Applied to Producing Wells in Unconventional Reservoirs
Authors: Nemoto Rafael H. , Hackworth Matthew R. , Pereyra Eduardo , Sarica Cem
Published: November 2020

Electrical Submersible Pumps (ESPs) are commonly applied to producing wells in unconventional reservoirs. Typically, the operator places the ESP in the vertical section to minimize installation risks; however, some operators have reported installing ESPs in the lateral section to improve operation and production. This paper will present a study of the interaction between reservoir inflow, wellbore geometry, and ESP operation using a commercial dynamic multiphase flow simulator (OLGA). The study will further quantify the benefits and disadvantages of deploying the ESP in the vertical and lateral sections of a horizontal well. The investigation uses operations data from a Permian basin well, with an ESP operating in the vertical section of a horizontal well. The dynamic simulation model was built and tuned to match the field data with two different production stages: early and late production. Hypothetical cases with the ESP located in the lateral section and with different well geometries (toe-up and toe-down) are also investigated. For the performance evaluation of different ESP deployment positions, the following indicators were considered: (a) production flow rate, (b) likelihood of pressure surging occurrence, and (c) flow pattern and gas volume fraction reaching the ESP system. Finally, the study provides guidelines on the ESP deployment location for improved operation and production.
Hydraulic-Fracture-Width Inversion Using Low-Frequency Distributed-Acoustic-Sensing Strain Data—Part I: Algorithm and Sensitivity Analysis
Authors: Liu Yongzan , Jin Ge , Wu Kan , Moridis George
Published: November 2020

Low-frequency distributed-acoustic-sensing (LF-DAS) data, which can be treated as linear-scaled strain variations, have been used recently to monitor hydraulic-fracturing treatments. Forward geomechanical modeling has been the subject of recent research efforts to better interpret the observed signatures of field LF-DAS data. To the best of our knowledge, there is no study that attempts to quantitatively characterize fracture geometries by directly inverting the LF-DAS strain data. In this study, we propose an inversion algorithm, in which the strains monitored by LF-DAS along an offset well are related to the fracture widths through a Green function. A 3D displacement-discontinuity method is used to construct the Green function. The least-squares method is first used to solve the linear system of equations. Regularization might be needed to stabilize the underdetermined system. Then, Markov-chain Monte Carlo (MCMC) simulations are conducted to generate fracture-width samples from the target distribution of LF-DAS strain data and to quantify uncertainties associated with the inverted widths.

The inversion results obtained by the least-squares method are nonunique, heavily depending on the a priori regularization information. Regardless of the additional constraints imposed on the linear system, the inverted fracture width at the monitor-well location is always consistent with the true value because the LF-DAS data show a dominant sensitivity of fracture width near the monitor well. MCMC simulation results confirm that the LF-DAS strain data can only impose constraints on fracture segments near the monitor well. Moreover, the average value of the inverted widths in the vicinity of the monitor well is usually the same as the width right at the monitor well, except for the very early time after fracture hit when there are sharp width variations near the fracture tip. Therefore, it is efficient to use a single width for each fracture during the inversion process. The presented algorithm is successfully applied to invert the width evolution near the monitor well as a function of injection time.

The results of this study demonstrate how much information can be obtained with high confidence from the inversion of LF-DAS strain data, which is beneficial for future use of LF-DAS data. The accurate estimation of fracture width at the monitor well can be used to calibrate hydraulic-fracturing models, improve the design of completion parameters such as proppant size, and provide the possibility of characterizing the whole fracture geometry with additional information or assumptions.
Understanding the Plugging Performance of HPAM-Cr (III) Polymer Gel for CO2 Conformance Control
Authors: Sun Xindi , Bai Baojun , Alhuraishawy Ali Khayoon , Zhu Daoyi
Published: November 2020

With the demand for conformance control in carbon dioxide (CO2) flooding fields, hydrolyzed polyacrylamide-chromium [HPAM-Cr (III)] polymer gel has been applied in fields for CO2 conformance control. However, the field application results are mixed with success and failure. This paper is intended to understand the HPAM-Cr (III) polymer gel plugging performance in CO2 flooding reservoirs through laboratory experiments and numerical analysis. We conducted core flooding tests to understand how the cycles of CO2 and water affect the HPAM-Cr (III) polymer gel plugging efficiency to CO2 and water during a water-alternating-gas (WAG) process. Berea Sandstone cores with the permeability range of 107 to 1225 md were used to evaluate the plugging performance in terms of residual resistance factor and breakthrough pressure, which is the minimum pressure required for CO2 to enter the gel-treated cores. We compared the pressure gradient from the near-wellbore to far-field with the gel breakthrough pressure, from which we analyzed under which conditions the gel treatment could be more successful. Results show that HPAM-Cr (III) polymer gel has higher breakthrough pressure in the low-permeability cores. The polymer gel can reduce the permeability to water much more than that to CO2. The disproportionate permeability reduction performance was more prominent in low-permeability cores than in high-permeability cores. The gel resistance to both CO2 and brine significantly decreased in later cycles. In high-permeability cores, the gel resistance to CO2 became negligible only after two cycles of water and CO2 injection. Because of the significant reduction of pressure gradient from near-wellbore to far-field in a radial flow condition and the dependence of breakthrough pressure on permeability and polymer concentration, we examined hypothetical reservoirs with no fractures, in which impermeable barriers separated high- and low-permeability zones and in which the gel was only placed in the high-permeability zone. We considered two scenarios: CO2 breaking through the gel and no CO2 breakthrough. No breakthrough represents the best condition in which the gel has no direct contact and can be stable in reservoirs for long. In contrast, the breakthrough scenario will result in the gel's significant degradation and dehydration resulting from CO2 flowing through the gel, which will cause the gel treatment to fail.
The distribution of refraction by age and gender in a non-myopic Chinese children population aged 6-12 years
Authors: Zhang Xiyan , Zhou Yonglin , Yang Jie , Wang Yan , Yang Wenyi , Gao Liuwei , Xiang Yao , Zhang Fengyun
Published: November 2020

Background: The Prevalence of myopia is increasing in China. This study aimed to explore the distribution of spherical equivalent (SE) and its association with age, body mass index (BMI), gender in a non-myopic Chinese children population aged 6 to 12 years. Methods: A total of 6362 students were recruited for ophthalmological investigation. Demographic and myopia related behavioral information was collected. SE value was measured by the Topcon RM-8900 or KR-800autorefractors. Potential independent risk factors were determined with Odds Ratio (OR) and 95% Confidence Interval (CI) by logistic regression analysis. We further constructed the nomogram model to predict future onset of myopia.Results: Among the study population, 3900 (61.3%) were non-myopic. The prevalence of myopia is 38.0% for boys and 39.5% for girls. The average SE values were 0.50±0.70 D for boys and 0.60±0.80 D for girls. The mean SE values decreased with age, and the value of height and BMI took on a stable trend. Threshold values for myopia varied across age groups and gender. Paternal myopia (OR: 1.22, 95%CI: 1.01-1.48), near-work activities on weekends (2.56, 1.17-5.61), and outdoor activities (0.68, 0.54-0.86) were associated with potential myopic in students. Conclusion: A series of age-gender based SE threshold values were established to predict myopia in Chinese children aged 6 to 12 years. High risk factors for myopia included paternal myopia, near-work activities on weekends, and outdoor activities. Countermeasures are encouraged to reverse the increasing trend of myopia in children.
There is no Dose-response Relationship between Allogeneic Blood Transfusion and Healthcare-associated Infection: A Retrospective Cohort Study
Authors: Lv Yu , Xiang Qian , Lin Jia , Jin Ying Zong , Fang Ying , Cai Hong M , Wei Qiong D , Wang Hui , Wang Chen , Chen Jing , Ye Jian , Xie Caixia , Li Ting L , Wu Yu J
Published: November 2020

BackgroundThe association between allogeneic blood transfusion (ABT) and healthcare-associated infection (HAI) is considered dose-dependent. However, this association may be confounded by transfusion duration, as prolonged hospitalization stay increases the risk of HAI. Also, it is not clear whether specific blood products have different dose-response risks.MethodsIn this retrospective cohort study, a logistic regression was used to identify confounding factors, and the association between specific blood products and HAI were analyzed. Then Cox regression and restricted cubic spline regression was used to visualize the hazard of HAI per transfusion product.ResultsOf 215338 inpatients observed, 4.16% were transfused with a single component blood product. With regard to these transfused patients, 480 patients (5.36 %) developed a HAI during their hospitalization stay. Logistic regression showed that red blood cells (RBCs) transfusion, platelets transfusion and fresh-frozen plasmas (FFPs) transfusion were risk factors for HAI [odds ratio (OR) 1.893, 95% confidence interval (CI) 1.656–2.163; OR 8.903, 95% CI 6.646–11.926 and OR 1.494, 95% CI 1.146–1.949, respectively]. However, restricted cubic spline regression analysis showed that there was no statistically dose-response relationship between different transfusion products and the onset of HAI.ConclusionsRBCs transfusion, platelets transfusion and FFPs transfusion were associated with HAI, but there was no dose-response relationship between them.
Proteasome Inhibitors Reduce Thrombospondin-1 Release in Human Dysferlin-Deficient Myotubes
Authors: Fernández-Simón Esther , Lleixà Cinta , Suarez-Calvet Xavier , Diaz-Manera Jordi , Illa Isabel , Gallardo Eduard , de Luna Noemí
Published: November 2020

Background Dysferlinopathies are a group of muscle disorders causing muscle weakness and absence or low levels of dysferlin, a type-II transmembrane protein and the causative gene of these dystrophies. Dysferlin is implicated in vesicle fusion, trafficking, and membrane repair. Muscle biopsy of patients with dysferlinopathy is characterized by the presence of inflammatory infiltrates. Studies in the muscle of both human and mouse models of dysferlinopathy suggest dysferlin deficient muscle plays a role in this inflammation by releasing thrombospondin-1. It has also been reported that vitamin D3 treatment enhances dysferlin expression. The ubiquitin-proteasome system recognizes and removes proteins that fail to fold or assemble properly and previous studies suggest that its inhibition could have a therapeutic effect in muscle dystrophies. Here we assessed whether inhibition of the ubiquitin proteasome system prevented degradation of dysferlin in immortalized myoblasts from a patients with two missense mutations in exon 44. MethodsTo assess proteasome inhibition we treated dysferlin deficient myotubes with EB1089, a vitamin D3 analog, oprozomib and ixazomib. Western blot was performed to analyze the effect of these treatments on the recovery of dysferlin and myogenin expression. TSP-1 was quantified using the enzyme-linked immunosorbent assay to analyze the effect of these drugs on its release. A membrane repair assay was designed to assess the ability of treated myotubes to recover after membrane injury and fusion index was also measured with the different treatments. Data were analyzed using a one-way ANOVA test followed by Tukey post hoc test and analysis of variance. A p≤0.05 was considered statistically significant. Results Treatment with proteasome inhibitors and EB1089 resulted in a trend towards an increase in dysferlin and myogenin expression. Furthermore, EB1089 and proteasome inhibitors reduced the release of TSP-1 in myotubes. However, no effect was observed on the repair of muscle membrane after injury. ConclusionsOur findings indicate that the ubiquitin-proteasome system might not be the main mechanism of mutant dysferlin degradation. However, its inhibition could help to improve muscle inflammation by reducing TSP-1 release.
Impact of COVID-19 on selected criminal activities in Dhaka, Bangladesh
Authors: Rashid Sungida
Published: November 2020

The COVID-19 pandemic has made a substantial impact on the historical criminal trend of the world. Using Dhaka Metropolitan Police (DMP) recorded open crime data of the total number of arrests, this article aims to understand how the frequency of selected crime trends has changed during the pandemic in Dhaka city, the capital of Bangladesh. Time-series forecasting models ARIMA (Auto Regressive Moving Average Model) are used to forecast the expected frequency of arrests in different crime types in 2020 in the absence of the pandemic. Forecasting techniques are applied to estimate six-month-ahead forecasts of the total number of arrests of arms dealing, vehicle theft, and illegal drug trafficking. The actual and predicted numbers of total arrests for vehicle thefts are decreased during pandemic while actual arrests in illegal drug trafficking show a steep upward trend- around 75% more than that of the expected frequencies. Estimated results are used to recognize scopes and suggestions for future research on the relationship between crimes and pandemic.
Longitudinal tracing of neurochemical metabolic disorders in working memory neural circuit and optogenetics modulation in rats with vascular cognitive impairment
Authors: Lin Huawei , Jin Tingting , Chen Lewen , Dai Yaling , Jia Weiwei , He Xiaojun , Yang Minguang , Li Jianhong , Liang Shengxiang , Wu Jinsong , Huang Jia , Chen Lidian , Liu Weilin , Tao Jing
Published: November 2020

Objective: Chronic cerebral ischemia leads to vascular cognitive impairment (VCI) that exacerbates along with ischemia time and eventually develops into dementia. Recent advances in molecular neuroimaging contribute to understand its pathological characteristics. We previously traced the anisotropic diffusion of water molecules suggests that chronic cerebral ischemia leads to irreversible progressive damage to white matter integrity. However, the abnormalities of gray matter activity following chronic cerebral ischemia remains not entirely understood.Methods: In this study, in vivo hydrogen proton magnetic resonance spectroscopy (1H-MRS) was applied to longitudinally track the neurochemical metabolic disorder of gray matter associated with working memory, and optogenetics modulation of neurochemical metabolism was performed for targeted treatment of VCI. Results: The results showed that the concentration of N-acetylaspartate (NAA) in the right hippocampus, left hippocampus, right medial prefrontal cortex (mPFC) and mediodorsal thalamus was decreased as early as 7 days after chronic cerebral ischemia, subsequently gamma-aminobutyric acid (GABA) declined whereas myo-inositol (mI) and glutamate (Glu) increased at 14 days, as well as choline (Cho) lost at 28 days, concurrently the change of Glu and GABA in the mPFC and hippocampus was ischemia time-dependent manner within 1 month. Behaviorally, working memory and object recognition memory were impaired at 14 days, 28 days that significantly correlated with neurochemical metabolic disorders. Interestingly, using optogenetics modulation of PV neurons in the mPFC, the metabolic abnormalities of NAA and GABA in working memory neural circuit could be repaired after chronic cerebral ischemia, together with behavior improvements. Conclusions: These findings suggested that as early as 1~4 weeks after chronic cerebral ischemia, the metabolism of NAA, Glu, mI and Cho was synchronously impaired in neural circuit of hippocampus-mediodorsal thalamus-mPFC, and the loss of GABA delayed in the hippocampus, and optogenetics modulation of parvalbumin (PV) neurons in the mPFC can improve the neurochemical metabolism of working memory neural circuit and enhance working memory.
Evaluation of symptoms, radiological findings, laboratory data and outcome in COVID-19 patients with chronic kidney disease at Tehran, Iran
Authors: Keshmiri Yasaman Sadat , Mirzaie Sina Khosravi , Sali Shahnaz , Yadegarynia Davood , Abolghasemi Sara , Tehrani Shabnam , Zamani Amir , Derisi Mohamad Mehdi
Published: November 2020

Background: Chronic kidney disease (CKD) patients are a large population and of significant importance. Except for having an underlying disease, they have some other risk factors, for example, old age, impaired immune function, and other comorbidities that make them more susceptible to the new SARS-COV2 infection.Methods: As data on CKD patients with SARS-CoV-2 Infection is limited, we decided to carry out a cross-sectional study at Labbafinezhad Hospital on 78 CKD patients with approved COVID-19 infection either on dialysis or not. We have also incorporated CKD patients with kidney transplant history. Results: The mean age of the patients was 64.04 years, including 53 women and 25 men. Among all symptoms, dyspnea (19.2%) was the most prevalent one. Laboratory data analysis shows an increase in LDH, Creatinine, and ESR and CRP levels. The most common finding on chest CT-Scan was bilateral ground-glass opacity detected in 31 (86.1%) patients, followed by pleural effusion (12.8%) and atelectasis (19%). Among included patients, 53 (74.6%) had hypoxia (o2 saturation 94% and lower), 47 (81%) had tachypnea (respiratory rate over 16) and 9 (23.1%) had some reduction in the level of consciousness (GCS lower than 15). Conclusion: Due to the important effect of underlying medical conditions on the outcome of COVID-19 patients, evaluation of clinical manifestations, radiologic findings, laboratory data, and outcome of COVID-19 patients with chronic kidney disease is important to establish a perspective for physicians to manage CKD patients.
Reaching the unreached: effectiveness and satisfaction with community-directed distribution of sulfadoxine-pyrimethamine for preventing malaria in pregnancy in rural South-East, Nigeria
Authors: Okedo-Alex Ijeoma Nkem , Akamike Ifeyinwa Chizoba , Alo Chihurumnanya , Agu Adaoha Pearl , Nzeh Chinyere Benedicta , Chinwendu Ndukwe Daniel , Okoro Odii Ogonna , Abateneh Dejene Derseh , Uneke Chigozie Jesse
Published: November 2020

Background Innovative community strategies to increase intermittent preventive treatment with sulfadoxine-pyrimethamine (IPTp-SP) coverage is advocated particularly in rural areas, where health infrastructure is weakest and malaria transmission highest. This study involved proof-of-concept implementation research to determine satisfaction with and effectiveness of community-directed distribution of IPTp-SP on uptake among pregnant women in Ebonyi State, Nigeria. Methods This before-and-after study was carried out in 2019 in a rural community in Ebonyi State Nigeria. The intervention involved advocacy visits, community-wide sensitizations on malaria prevention, house-to-house directly observed IPTp-SP administration, and follow-up visits by trained community-selected community-directed distributors (CDDs). Monthly IPTp-SP coverage was assessed over 5 months and data analysed using SPSS version 20.Results During the study, 229 women received the first dose of IPTp while 60 pregnant women received 5 or more doses of IPTp. The uptake of ≥3 IPTp doses increased from 31.4% before the community-directed distribution of IPTp to 71.6% (P <0.001) by the fourth month post-initiation of the community-directed distribution of IPTp. Sleeping under insecticide-treated net (ITN) the night before the survey increased from 62.4 to 84.3% (P <0.001) while reporting of fever during pregnancy decreased from 64.9 to 17.0% (P <0.001). Although antenatal clinic utilization increased in the primary health centre serving the community, traditional birth attendants and patent medicine vendors in the community remained more patronized. Post-intervention, most mothers rated CDD services well (93.6%), were satisfied (97.6%), and preferred community IPTp administration to facility administration (92.3%).Conclusions Community-directed distribution of IPTp-SP improved uptake of IPTp-SP and ITN use. Mothers were satisfied with the services. The authors recommend sustained large-scale implementation of community-directed distribution of IPTp with active community engagement.
Problems in measuring the JTC-bias in patients with psychotic disorders with the fish task: A secondary analysis of a baseline assessment of a randomized controlled trial 
Authors: Pytlik Nico , Soll Daniel , Hesse Klaus , Moritz Steffen , Bechdolf Andreas , Herrlich Jutta , Kircher Tilo , Klingberg Stefan , Landsberg Martin W. , Müller Bernhard W. , Wiedemann Georg , Wittorf Andreas , Wölwer Wolfgang , Wagner Michael , Mehl Stephanie
Published: November 2020

Background: The jumping to conclusions bias (JTC) is considered to be an important causal factor in theoretical models for the formation and maintenance of delusions. However, recent meta-analytic findings show a rather equivocal pattern of results regarding associations between JTC and delusions. Thus, the present study aims to investigate in a large sample whether the JTC-bias is more pronounced in patients with psychotic disorders in comparison to controls and whether the JTC bias is associated with a more severe delusional conviction, persecutory delusions, and positive symptoms in general.Methods: Patients with psychotic disorders (n = 300) enrolled in a therapy trial and healthy controls (n = 51) conducted a variant of the beads task (fish task) as a measure for the JTC-bias at the start of the trial. Further, clinical interviews were used to assess patients’ delusional severity and delusional conviction. Results: There were no statistically significant differences between patients with psychotic disorders (with 53% displaying the JTC-bias) and controls (41%). Furthermore, there were no statistically significant correlations between JTC measures and persecutory delusions, delusional conviction, and positive symptoms.Conclusions: We found no differences in JTC between patients with psychotic disorders and healthy controls, which is in part in line with meta-analytic findings using a wide range of JTC task variants. Interestingly, patients with psychotic disorders displayed JTC rates commonly found in the literature, while healthy control subjects showed an unexpectedly high level of JTC. The task variant we used in the present study (fish task) is discussed as a potential reason for our results, as it may induce a more deliberative reasoning style in controls as compared to the traditional beads task. Furthermore, possible implications for the measurement of the JTC-bias, in general, are discussed.Trial Registration: ISRCTN29242879 (isrctn.com), date of registration: April 12th 2006
The pathological features of hip abductor tendon tears – a cadaveric study
Authors: Zhu Mark , Smith Brittany , Krishna Sanjeev , Musson David S. , Riordan Peter R. , McGlashan Sue R. , Cornish Jillian , Munro Jacob T.
Published: November 2020

Background: The hip abductors are crucial in maintaining pelvic stability. Tears in these tendons are common and often debilitating. There is uncertainty regarding both the histological and macroscopic features of hip abductor tears. This study aims to clarify both the macroscopic and microscopic features of the tendon and enthesis in hip abductor tendon tears.Methods: Thirty-six cadavers with an average age of 81 were dissected, and the hip abductor mechanisms removed en-bloc. The presence, location and size of the tears were recorded and analysed. The samples were processed into histological blocks and viewed using both transmitted and polarised light. Tendon histology was graded using the modified Movin’s score in three sections (deep, middle and superficial layers) and the enthesis graded separately using 5-point criteria. Analysis of variance was used to confirm histological features associated with tears. Results: Tears were found in 24 of 36 samples (67%). The most common finding was an isolated tear in the gluteus minimus (46%), followed by concurrent gluteus medius and gluteus minimus tears (33%). Histology revealed significantly more degeneration in both the tendon (p=0.0005) and enthesis (p=0.0011) when tears were present. Furthermore, these changes were concentrated in the deeper layers of the tendon (p=0.0002) and enthesis (p=0.003). Conclusion: This study demonstrated degeneration as the primary pathology underlying hip abductor tendon tears. Degenerative changes occur in both the tendon and enthesis, with the deeper layers predominantly affected. These findings are important for guiding surgical repair techniques and to aid the development of novel materials and biologics.
Hiding in Plain Sight: The Absence of Consideration of the Gendered Dimensions in ‘Source’ Country Perspectives of Health Worker Migration
Authors: Bourgeault Ivy Lynn , Runnels Vivien , Atanackovic Jelena , Spitzer Denise , Roberts Margaret Walton
Published: November 2020

Background: Gender roles and relations affect both the drivers and experiences of health worker migration, yet policy responses rarely consider these gender dimensions. This lack of explicit attention from source country perspectives can lead to inadequate policy responses. Methods: A Canadian-led research team with co-investigators in the Philippines, South Africa, and India examined the causes, consequences and policy responses to the international migration of health workers from these ‘source’ countries through documentary, interview and survey data with workers and country-based stakeholders. Here we undertake an explicit gender-based analysis highlighting the gender-related influences and implications that emerged from the published literature and policy documents from the decade 2005 to 2015; in-depth interviews with 117 stakeholders; and surveys conducted with 3,580 health workers. Results: The literature on health worker migration from South Africa, India and the Philippines reveal that gender can mediate access and participation in health worker training, employment, and migration. Our analysis of survey data from nurses, physicians and other health workers in South Africa, India and the Philippines and interviews with policy stakeholders, however, reveals a curious absence of how gender might mediate health worker migration. Stakeholders in South Africa described female health workers as “preferred” for “innate” personal characteristics and cultural reasons, and in India that men are directed away from nursing roles particularly because they are considered only for women. That inadequate remuneration was identified as a key migration driver amongst survey respondents in India and the Philippines, where nurses predominated in our sample, may be linked to the impact of underlying gender-based pay inequity. The literature suggests that migration may improve social status of women nurses, but it may also expose them to deskilling, as a result of intersecting racism and sexism in their destination country. Regardless of these underlying influences in migration decision-making, gender is rarely considered either as an important contextual influence or analytic category in the policy responses.Conclusion: An explicit gender-based analysis on health worker migration could offer useful insights for health and social policy responses and emphasize the importance of equity considerations to their decisions in these countries.
Craniofacial morphology/phenotypes influence on mandibular range of movement in the design of a mandibular advancement device
Authors: Sanz Pedro Mayoral , Reyes Mariano Garcia , Torras Alex Bataller , Castillo JA Cabrera , Lagravere Manuel
Published: November 2020

Background. The mandibular opening path movements have different directions according to the craniofacial morphology of the patient but always downward and backward, therefore increasing the collapse of the upper airway. The aim of this work is to determine if there is a relationship between the craniofacial morphology and the mandibular movement to help understand the impact on the mandibular position. Methods. 52 students with full permanent dentition aged 19 to 23 years (mean 21.3 SD 1.7; 29 females and 23 males), participated in the study. Each subject had a lateral cephalometric radiograph taken. The opening angle was determined for two levels of vertical openings at 5 and 10 mm.Results. The opening angle showed a greater variability between subjects ranging from 63.15 to 77.08 for 5 mm angle and from for 61.65 to 75.72 for the 10 mm angle. Differences of facial phenotypes was evident when comparing the individual dissoccluding angle of the low angle horizontal pattern and high angle vertical pattern.Conclusions. The opening angle is related to craniofacial morphology with higher vertical anterior and shorter anteroposterior faces having a more horizontal path of mandibular movement than shorter vertical anterior and longer anteroposterior subjects who have a more vertical path.
Influencing Factors for Prevention of Postpartum Hemorrhage and Early Detection of Childbearing Women at Risk in Northern Province of Rwanda: Beneficiary and Health Worker Perspectives
Authors: Bazirete Oliva , Nzayirambaho Manassé , Umubyeyi Aline , Uwimana Marie Chantal , Marilyn Evans
Published: November 2020

Background: Reduction of maternal mortality and morbidity is a major global health priority. However, much remains unknown regarding factors associated with postpartum hemorrhage (PPH) among childbearing women in the Rwandan context. The aim of this study is to explore the influencing factors for prevention of PPH and early detection of childbearing women at risk as perceived by beneficiaries and health workers in the Northern Province of Rwanda. Methods: A qualitative descriptive exploratory study was drawn from a larger sequential exploratory‐mixed methods study. Semi‐structured interviews were conducted with 11 women who experienced PPH within the 6 months prior to interview. In addition, focus group discussions were conducted with: women’s partners or close relatives (2 focus groups), community health workers (CHWs) in charge of maternal health (2 focus groups) and health care providers (3 focus groups). A socio ecological model was used to develop interview guides to describe factors related to early detection and prevention of PPH in consideration of individual attributes, interpersonal, family and peer influences, intermediary determinants of health and structural determinants. The research protocol was approved by the University of Rwanda, College of Medicine and Health Sciences Institutional Ethics Review Board. Results: We generated four interrelated themes: (1) Meaning of PPH: beliefs, knowledge and understanding of PPH: (2) Organizational factors; (3) Caring and family involvement and (4) Perceived risk factors and barriers to PPH prevention. The findings from this study indicate that PPH was poorly understood by women and their partners. Family members and CHWs feel that their role for the prevention of PPH is to get the woman to the health facility on time. The main factors associated with PPH as described by participants were multiparty and retained placenta. Low socioeconomic status and delays to access health care were identified as the main barriers for the prevention of PPH. Conclusions: Addressing the identified factors could enhance early prevention of PPH among childbearing women. Placing emphasis on developing strategies for early detection of women at higher risk of developing PPH, continuous professional development of health care providers, developing educational materials for CHWs and family members could improve the prevention of PPH. Involvement of all levels of the health system was recommended for a proactive prevention of PPH. Further quantitative research, using case control design is warranted to develop a screening tool for early detection of PPH risk factors for a proactive prevention.
Maintaining proper health records improves machine learning predictions for novel 2019-nCoV
Authors: KHAN KOFFKA , Ramsahai Emilie
Published: November 2020

Background: An ongoing outbreak of a novel coronavirus (2019-nCoV) pneumonia continues to aect the whole world including major countries such as China, USA, Italy, France and the United Kingdom. We present outcome ('recovered', 'isolated' or 'death') risk estimates of 2019-nCoV over 'early' datasets. A major consideration is the likelihood of death for patients with 2019-nCoV.Method: Accounting for the impact of the variations in the reporting rate of 2019-nCoV, we used machine learning techniques (AdaBoost, bagging, extra-trees, decision trees and k-nearest neighbour classiers) on two 2019-nCoVdatasets obtained from Kaggle on March 30, 2020. We used 'country', 'age' and 'gender' as features to predict outcome for both datasets. We included the patient's 'disease' history (only present in the second dataset) to predict the outcome for the second dataset.Results: The use of a patient's 'disease' history improves the prediction of 'death' by more than 7-fold. The models ignoring a patent's 'disease' history performed poorly in test predictions.Conclusion: Our ndings indicate the potential of using a patient's 'disease' history as part of the feature set in machine learning techniques to improve 2019-nCoV predictions. This development can have a positive eect on predictive patient treatment and can result in easing currently overburdened healthcare systems worldwide, especially with the increasing prevalence of second and third wave re-infections in some countries.
A nomogramic model based on clinical and laboratory parameters at admission for predicting the survival of COVID-19 patients
Authors: Ma Xiaojun , Wang Huifang , Huang Junwei , Geng Yan , Jiang Shuqi , Zhou Qiuping , Chen Xuan , Hu Hongping , Li Weifeng , Zhou Chengbin , Gao Xinglin , Peng Na , Deng Yiyu
Published: November 2020

Background and AimCOVID-19 has become a major global threat. The present study aimed to develop a nomogram model to predict the survival of COVID-19 patients based on their clinical and laboratory data at admission.MethodsCOVID-19 patients who were admitted at Hankou Hospital and Huoshenshan Hospital in Wuhan, China from January 12, 2020 to March 20, 2020, whose outcome during the hospitalization was known, were retrospectively reviewed. The categorical variables were compared using Pearson’s χ2-test or Fisher’s exact test, and continuous variables were analyzed using Student’s t-test or Mann Whitney U-test, as appropriate. Then, variables with a P-value of ≤0.1 were included in the log-binomial model, and merely these independent risk factors were used to establish the nomogram model. The discrimination of the nomogram was evaluated using the area under the receiver operating characteristic curve (AUC), and internally verified using the Bootstrap method.ResultsA total of 262 patients (134 surviving and 128 non-surviving patients) were included in the analysis. Seven variables, which included age (relative risk [RR]: 0.905, 95% confidence interval [CI]: 0.868-0.944; P<0.001), chronic heart disease (CHD, RR: 0.045, 95% CI: 0.0097-0.205; P<0.001, the percentage of lymphocytes (Lym%, RR: 1.125, 95% CI: 1.041-1.216; P=0.0029), platelets (RR: 1.008, 95% CI: 1.003-1.012; P=0.001), C-reaction protein (RR: 0.982, 95% CI: 0.973-0.991; P<0.001), lactate dehydrogenase (LDH, RR: 0.993, 95% CI: 0.990-0.997; P<0.001) and D-dimer (RR: 0.734, 95% CI: 0.617-0.879; P<0.001), were identified as the independent risk factors. The nomogram model based on these factors exhibited a good discrimination, with an AUC of 0.948 (95% CI: 0.923-0.973).ConclusionA nomogram based on age, CHD, Lym%, platelets, C-reaction protein, LDH and D-dimer was established to accurately predict the prognosis of COVID-19 patients. This can be used as an alerting tool for clinicians to take early intervention measures, when necessary.
Development of an Engineered Peptide Antagonist against Periostin to Overcome Doxorubicin Resistance in Breast Cancer
Authors: Oo Khine Kyaw , Kamolhan Thanpawee , Soni Anish , Thongchot Suyanee , Mitrpant Chalermchai , O-charoenrat Pornchai , Thuwajit Chanitra , Thuwajit Peti
Published: November 2020

Background: Chemoresistance is one of the main problems in treatment of cancer. Periostin (PN) is a stromal protein which is mostly secreted from cancer associated fibroblasts in the tumor microenvironment and can promote cancer progression including cell survival, metastasis, and chemoresistance. The main objective of this study was to develop an anti-PN peptide from the bacteriophage library to overcome PN effects in breast cancer (BCA) cells. Methods: A twelve amino acids bacteriophage display library was used for biopanning against the PN active site. A selected clone was sequenced and analyzed for peptide primary structure. A peptide was synthesized and tested for the binding affinity to PN. PN effects including a proliferation, migration and a drug sensitivity test were performed using PN overexpression BCA cells or PN treatment and inhibited by an anti-PN peptide. An intracellular signaling mechanism of inhibition was studied by western blot analysis. Lastly, PN expressions in BCA patients were analyzed along with clinical data. Results: The results showed that a candidate anti-PN peptide was synthesized and showed affinity binding to PN. PN could increase proliferation and migration of BCA cells and these effects could be inhibited by an anti-PN peptide. There was significant resistance to doxorubicin in PN-overexpressed BCA cells and this effect could be reversed by an anti-PN peptide in associations with phosphorylation of AKT and expression of survivin. In BCA patients, serum PN showed a correlation with tissue PN expression but there was no significant correlation with clinical data. Conclusions: This finding supports that anti-PN peptide is expected to be used in the development of peptide therapy to reduce PN-induced chemoresistance in BCA.