bluuebunny/crossref_metadata_2025 huggingface dataset:
Artificial Intelligence and Robotics in the Oil Industry: Will it Take My Job?
Authors: Agbaji Armstrong Lee
Published: December 2021

Historically, the oil and gas industry has been slow and extremely cautious to adopt emerging technologies. But in the Age of Artificial Intelligence (AI), the industry has broken from tradition. It has not only embraced AI; it is leading the pack. AI has not only changed what it now means to work in the oil industry, it has changed how companies create, capture, and deliver value. Thanks, or no thanks to automation, traditional oil industry skills and talents are now being threatened, and in most cases, rendered obsolete. Oil and gas industry day-to-day work is progressively gravitating towards software and algorithms, and today’s workers are resigning themselves to the fact that computers and robots will one day "take over" and do much of their work. The adoption of AI and how it might affect career prospects is currently causing a lot of anxiety among industry professionals.

This paper details how artificial intelligence, automation, and robotics has redefined what it now means to work in the oil industry, as well as the new challenges and responsibilities that the AI revolution presents. It takes a deep-dive into human-robot interaction, and underscores what AI can, and cannot do. It also identifies several traditional oilfield positions that have become endangered by automation, addresses the premonitions of professionals in these endangered roles, and lays out a roadmap on how to survive and thrive in a digitally transformed world.

The future of work is evolving, and new technologies are changing how talent is acquired, developed, and retained. That robots will someday "take our jobs" is not an impossible possibility. It is more of a reality than an exaggeration. Automation in the oil industry has achieved outcomes that go beyond human capabilities. In fact, the odds are overwhelming that AI that functions at a comparable level to humans will soon become ubiquitous in the industry. The big question is: How long will it take?

The oil industry of the future will not need large office complexes or a large workforce. Most of the work will be automated. Drilling rigs, production platforms, refineries, and petrochemical plants will not go away, but how work is done at these locations will be totally different. While the industry will never entirely lose its human touch, AI will be the foundation of the workforce of the future. How we react to the AI revolution today will shape the industry for generations to come. What should we do when AI changes our job functions and workforce? Should we be training AI, or should we be training humans?
The Effects of Interfacial Tension Dependent Relative Permeability on Sweep Efficiency and Oil Recovery Under Different Gas Injection Composition
Authors: Abd Karim Mohd Ghazali , Hidayat Wahyu , Abdulelah Alzahrani
Published: December 2021

The objective of this paper is to investigate the effects of interfacial tension dependent relative permeability (Kr_IFT) on oil displacement and recovery under different gas injection compositions utilizing a compositional simulation model. Oil production under miscible gas injection will result in variations of interfacial tension (IFT) due to changes in oil and gas compositions and other reservoir properties, such as pressure and temperature. Laboratory experiments show that changes in IFT will affect the two-phase relative permeability curve (Kr), especially for oil-gas system. Using a single relative permeability curve during the process from immiscible to miscible conditions will result in inaccurate gas mobility against water, which may lead to poor estimation of sweep efficiency and oil recovery. A synthetic sector compositional model was built to evaluate the effects of this phenomenon. Several simulation cases were investigated over different gas injection compositions (lean, rich and CO2), fluid properties and reservoir characterizations to demonstrate the impact of these parameters. Simulation model results show that the application of Kr_IFT on gas injection simulation modelling has captured different displacement behavior to provide better estimation of oil recovery and identify any upside potential.
Multi-Fidelity Bayesian Approach for History Matching in Reservoir Simulation
Authors: Santoso Ryan , He Xupeng , Alsinan Marwa , Figueroa Hernandez Ruben , Kwak Hyung , Hoteit Hussein
Published: December 2021

History matching is a critical step within the reservoir management process to synchronize the simulation model with the production data. The history-matched model can be used for planning optimum field development and performing optimization and uncertainty quantifications. We present a novel history matching workflow based on a Bayesian framework that accommodates subsurface uncertainties. Our workflow involves three different model resolutions within the Bayesian framework: 1) a coarse low-fidelity model to update the prior range, 2) a fine low-fidelity model to represent the high-fidelity model, and 3) a high-fidelity model to re-construct the real response. The low-fidelity model is constructed by a multivariate polynomial function, while the high-fidelity model is based on the reservoir simulation model. We firstly develop a coarse low-fidelity model using a two-level Design of Experiment (DoE), which aims to provide a better prior. We secondly use Latin Hypercube Sampling (LHS) to construct the fine low-fidelity model to be deployed in the Bayesian runs, where we use the Metropolis-Hastings algorithm. Finally, the posterior is fed into the high-fidelity model to evaluate the matching quality. This work demonstrates the importance of including uncertainties in history matching. Bayesian provides a robust framework to allow uncertainty quantification within the reservoir history matching. Under uniform prior, the convergence of the Bayesian is very sensitive to the parameter ranges. When the solution is far from the mean of the parameter ranges, the Bayesian introduces bios and deviates from the observed data. Our results show that updating the prior from the coarse low-fidelity model accelerates the Bayesian convergence and improves the matching convergence. Bayesian requires a huge number of runs to produce an accurate posterior. Running the high-fidelity model multiple times is expensive. Our workflow tackles this problem by deploying a fine low-fidelity model to represent the high-fidelity model in the main runs. This fine low-fidelity model is fast to run, while it honors the physics and accuracy of the high-fidelity model. We also use ANOVA sensitivity analysis to measure the importance of each parameter. The ranking gives awareness to the significant ones that may contribute to the matching accuracy. We demonstrate our workflow for a geothermal reservoir with static and operational uncertainties. Our workflow produces accurate matching of thermal recovery factor and produced-enthalpy rate with physically-consistent posteriors. We present a novel workflow to account for uncertainty in reservoir history matching involving multi-resolution interaction. The proposed method is generic and can be readily applied within existing history-matching workflows in reservoir simulation.
Laser Technology for Downhole Applications; Past, Present and Future
Authors: Batarseh Sameeh , Mutairi Saad , San Roman Alerigi Damian , Al Harith Abdullah
Published: December 2021

The objective of this work is to provide an overview of high power laser program since it is inception and to provide the strategy to make it reality. An overview of the past two decades, current and future plan to deploy the technology in the field.

Laser attracted the oil and gas industry as an innovative non-damaging technology and alternatives to current practices. The lab success conducted over the past 20 years performing experiments on thousands of representative rock samples proved the key parameter for successful laser operation in the field. The technology is not only a non-damaging but also improves flow properties and communication between the wellbore and the hydrocarbon bearing formation.

For the past two decades, researchers attempted to deploy high power laser technology for several downhole applications due to its unique properties such as accuracy, precision, and power. The power of the earlier laser generation was insufficient to penetrate subsurface formations. Recent advancement in the high power laser technology generates new and evolved systems that are more compact, efficient, and cost effective for downhole applications.

Thousands of rocks have been exposed to high power lasers radiations for several downhole applications such as perforation, drilling and heating. The success of the technology demonstrated that in all rock types, the flow properties were enhanced regardless of their compressive strength and hardness. Laser also has unique futures such as the precision in controlling and orienting the energy in any direction regardless of the reservoir stress orientation and magnitude. The beam is generated at the surface and delivered downhole via fiber optics cable, it can be targeted directly to the pay zone to enable production from challenging zones that cannot and could not be achieved with current technology. The technology provides small footprint and environmentally friendly technology, it provides waterless technology as an alternative to water base fracturing technology.
Managing Sanding Risk in Sandstone Reservoir Through a New Constitutive Model
Authors: Subbiah Surej Kumar , Samsuri Ariffin , Mohamad-Hussein Assef , Jaafar Mohd Zaidi , Chen Yingru , Pearce Andrew , Ranjan Kumar Rajeev , Paramanathan Rajendra Nath , de Groot Lex
Published: December 2021

Sandstone reservoir failure during hydrocarbon production can cause negative impact on the oil/gas field development economics. Loss of integrity and hydrocarbon leakage due to downhole or surface erosion can decrease the risk of operational safety. Therefore, a proper understanding of the best formulation to manage and find the balance between productivity and sand risk is very important. Making decisions for the best and most economical completion design needs a full and proper sanding risk analysis driven by geomechanics modeling. The accuracy of modeling the reservoir rock mechanical behavior and the failure analysis depends on the selection of the constitutive model (failure criteria) specially to understand the failure and post failure mechanisms. Thus, an appropriate constitutive model/criterion is required as most of the current model/criteria are not developed for a weak rock material honoring the non-linearity and post failure (softening) process. Therefore, a new and novel elasto-plastic constitutive model for sandstone rock has been investigated and developed. The effort started with a sequence of triaxial tests at different confining pressures on core samples. Different types of rock have been tested during the developing and validation of the constitutive model. Comparison with other existing failure criteria was also performed. As the results, the newly developed constitutive model is better honoring the full spectrum of elasto-plastic rock mechanical behavior (softening and post-failure) which is important for oil and gas applications, specifically for sand production and drilling i.e. failure stabilization due to stress relief. The formulation and process are demonstrated with a case study for an old gas field, where a few gas wells have been shut-in due to severe sand production. The sand production predictive models have been validated with downhole pressure. The wells have been side-tracked and recompleted using the new sand failure prediction, using the new formulation resulted in restoring sand-free production at former rates. The novelty of this study would be in finding the right formula to best design the predictive model and to avoid any sand production when using the newly developed constitutive model.
An Experimental and Simulation Study of CO2 Sequestration in an Underground Formations; Impact on Geomechanical and Petrophysical Properties
Authors: Fatima Sobia , Khan Hafiz Muhammad Mutahhar , Tariq Zeeshan , Abdalla Mohammad , Mahmoud Mohamed
Published: December 2021

Carbon dioxide (CO2) sequestration is a technique to store CO2 into an underground formation. CO2 can cause a severe reaction with the underground formation and injection tubing inside the well. Successful CO2 storage into underground formations depends on many factors such as efficient sealing, no escaping from the storage, and minimum corrosion to injection tubing/casing. Therefore, proper planning involving thorough study and reaction kinetics of CO2 with the underground formation is indeed necessary for proper planning.

The main aim and objective of this study are to investigate the effect of CO2 storage with different cap rocks such as tight carbonate and shale under simulated reservoir conditions. The samples were stored for different times such as 10, 20, and 120 days. The objectives of the study were achieved by carrying out extensive laboratory experiments before and after sequestration. The laboratory experiments included were rock compressive and tensile strength tests, petrophysical tests, and rock mechanical tests. The laboratory results were later used to investigate the reaction kinetics study of CO2 with the underground formation using CMG simulation software. The effect of injection rate, the point of injection, purity of the injection fluid, reservoir heterogeneity, reservoir depth, and minimum miscibility pressure was analyzed.

In this simulation model, CO2 is injected for 25 years using CMG-GEM simulation software and then the fate of CO2 post injection is modeled for the next 225 years. The simulation results showed a notable effect on the mechanical strength and petrophysical parameters of the rock after sequestration, also the solubility of CO2 decreases with the increase in salinity and injection pressure. The results also showed that the storage of CO2 increases the petrophysical properties of porosity and permeability of the formation rock when the storage period is more than 20 days because of calcite precipitation and CO2 dissolution. A storage period of fewer than 20 days does not show any significant effect on the porosity and permeability of carbonate reservoir rock. A sensitivity analysis was carried out which showed that the rate of CO2 sequestration is sensitive to the mineral-water reaction kinetic constants. The sensitivity of CO2 sequestration to the rate constants decreases in magnitude respectively for different clay minerals.

The new simulation model considers the effect of reaction kinetics and geomechanical parameters. The new model is capable of predicting the compatibility of CO2 sequestration for a particular field for a particular time.
Utilizing Microseismic to Monitor Fracture Geometry in a Horizontal Well in a Tight Sandstone Formation
Authors: Sani Abu M. , AlQasim Hatim S. , Alidi Rayan A.
Published: December 2021

This paper presents the use of real-time microseismic (MS) monitoring to understand hydraulic fracturing of a horizontal well drilled in the minimum stress direction within a high-temperature high-pressure (HTHP) tight sandstone formation. The well achieved a reservoir contact of more than 3,500 ft. Careful planning of the monitoring well and treatment well setup enabled capture of high quality MS events resulting in useful information on the regional maximum horizontal stress and offers an understanding of the fracture geometry with respect to clusters and stage spacing in relation to fracture propagation and growth. The maximum horizontal stress based on MS events was found to be different from the expected value with fracture azimuth off by more than 25 degree among the stages. Transverse fracture propagation was observed with overlapping MS events across stages. Upward fracture height growth was dominant in tighter stages. MS fracture length and height in excess of 500 ft and 100 ft, respectively, were created for most of the stages resulting in stimulated volumes that are high. Bigger fracture jobs yielded longer fracture length and were more confined in height growth. MS events fracture lengths and heights were found to be on average 1.36 and 1.30 times, respectively, to those of pressure-match.
Experimental Study and Prediction Model for Hydrate Plugging Formation in Single-Pass Gas-Dominated Pipes with Diameter Reduction
Authors: Zhang Jianbo , Wang Zhiyuan , Chen Shengnan , Pei Jihao , Ma Nan , Tong Shikun , Lou Wenqiang , Sun Baojiang
Published: December 2021

Gas hydrate plugging in flowlines acts as a major blockage risk in oil, gas, and natural gas hydrate production. Current studies on hydrate plugging is mainly conducted in pipes with a constant diameter, whereas the effects of varying diameters have been less explored. Pipes with diameter reductions are very common in the oil and gas production process. Herein, by performing experiments with pipes of four different sizes, including one with a constant diameter and three with diameter reductions, the hydrate plugging in single-pass gas-dominated pipes with diameter reduction is investigated systematically, the results of which show that the existence of diameter reduction can facilitate the deposition of hydrate particles on pipe walls and the formation of a hydrate deposition layer. Meanwhile, hydrate sloughing occurs during the growth of the hydrate deposition layer under fluid shear force. With the increase in the diameter reduction ratio or subcooling for hydrate formation, the hydrate deposition is observed to increase significantly, thus resulting in the reduction of time for hydrate plugging. According to these results, the hydrate plugging mechanism in pipes with diameter reduction is proposed. Further, in combination with the hydrate deposition difference between the inside and outside of the arc-shaped low-speed area, a new numerical model is established for hydrate plugging prediction in the pipe with diameter reduction, which can predict the growth and evolution of the hydrate deposition layer accurately with the consideration of the diameter’s reduction. The results of this work provide a valuable guidance for the targeted prevention and management of hydrate plugging in flowlines with diameter reductions.
Effectiveness of a Primary Care Program to Increase Physical Activity in People With Dementia and Their Family Caregivers (AFISDEMYF Study).
Authors: DE DIOS-RODRIGUEZ Elena , PATINO-ALONSO María C , GONZÁLEZ-SÁNCHEZ Susana , RIPOLL Joana , TAMAYO-MORALES Olaya , MORA-SIMÓN Sara , UNZUETA-ARCE Jaime , GÓMEZ-MARCOS Manuel A , GARCÍA-ORTIZ Luis , RODRÍGUEZ-SÁNCHEZ Emiliano
Published: December 2021

Aim: To evaluate the effectiveness of an intervention in primary health care designed to increase physical activity in people with dementia and their family caregivers.Methods: A cluster-randomized multicentre clinical trial was carried out.Participants: 140 people with dementia (median age 82 years;63.6% women) and 176 caregivers (median age 62 years ;72.7% women). Seventy patients and 80 caregivers were assigned to the Control Group (CG) and 70 patients and 96 caregivers to the Intervention Group (IG). The physical activity was measured with the pedometer and with the IPAQ-SF questionnaire. The intervention consisted of applying in primary care the program promoting physical activity (PEPAF) for 3 months. The changes observed at 6 months were analyzed. Results:In people with dementia, in the pedometer assessment a decrease was observed in both groups, but it was larger in the CG both in the total number step/day lower in the IG than in the CG and in the aerobic steps / day (52.89 vs -615.93). The activity reported with the IPAQ-SF decreased more in IG, both in the MET/min/week (-258.470 vs -148.23) and in the MVPA min/week. In caregivers the pedometer assessment showed that total steps/day increased more in the IG, as did aerobic steps/day (356.91 vs -12.95). The IPAQ-SF a smaller increase in global activity was declared in the IG than in the CG (545.25 MET/min/week vs 609.55), but the increase in vigorous activity was greater. No differences were found in changes in the functional status and the cognitive performances of people with dementia nor in the mental health in the caregivers, but systolic blood pressure, the Family APGAR and overload in the IG did improve.Conclusions: The results suggest that the intervention carried out may be effective on physical activity in both patients and caregivers. It can also improve systolic blood pressure, the Family APGAR and overload in caregivers. This is the first study to implement a primary care intervention aimed at simultaneously increasing physical activity in people with dementia and their relatives. These results reinforce the importance of using objective measures in clinical trials in people with dementia.Trial registration number: NCT 02044887.
More Adherence To A Mediterranean Dietary Pattern is Associated With A Lower Insomnia Score
Authors: yaghtin Zahra , Yuzbashian Emad , Ghayour-mobarhan Majid , Khayyatzadeh Sayyed Saeid
Published: December 2021

Background: Previous studies has shown that low quality diet is correlated with chronic sleep disorders. Mediterranean dietary pattern is considered as a high quality diet which has been shown to have beneficial effects on overall health. Thus, the aim of our study was to investigate the correlation between adherence to Mediterranean dietary pattern and insomnia score in a population of adolescent girls.Methods: Total Data of 734 adolescent girls between 12-18 years old has been considered in this cross-sectional study. To assess dietary intake, a food frequency questionnaire was used. To assess the inherence to Mediterranean dietary style, a modified model of Mediterranean diet was applied and the scores were ranged from 0-9. A valideated version of Insomnia Severity Index questionnaire wss used to assess insomnia. To explore the associations between MED-style diet and insomnia, logistic regression was conducted in crude and adjusted models.Results: The participants with higher adherence to MED-style diet had higher intake of fruits, vegetables, nuts, fish, total energy intake, carbohydrate, dietary fiber, potassium, Beta-carotene, vitamin C, iron and folate. A significant inverse association between adherence to the MED-style diet score and insomnia score was obtained in crude model (β= -0.125; P-value = 0.019) and also after adjustment for confounding variables (β= -0.120; P=0.048).Conclusion: There is an inverse relationship between adherence to the Mediterranean dietary style and the prevalence of insomnia among Iranian adolescent girls. Prospective studies are necessary to confirm these results and clarify whether a causal relationship exists.
Professional Self-Understanding of Teachers in Different Career Stages: A Phenomenological Analysis
Authors: Yağan Ersin , Özgenel Mustafa , Baydar Fatih
Published: December 2021

Teachers’ sense of identity plays a central role in understanding their actions as individuals inside and outside the classroom. Therefore, it is important to determine teachers’ understanding of who they are. Thus, teachers’ opinions about their professional self-understanding in the study were aimed to be analysed. In line with this purpose, the qualitative research method was used to address teachers’ views on their professional self-understanding holistically, and the research was carried out according to the phenomenology pattern. The research study group consists of 44 teachers working in primary, secondary, and high schools located in the Pendik district of Istanbul. Research data were obtained as a result of in-depth interviews with teachers through semi-structured interview forms. The findings obtained were grouped under five themes: “Image, Respect, Job Motivation, Perception of Duty, and Future Views”, taking into account the relevant literature. The study revealed that professional self-understanding is closely affected by emotions and teachers’ social status.
Therapeutic Exercise to Improve Motor Function Among Children with Down Syndrome Aged 0 to 3 Years: A Systematic Literature Review
Authors: Rodríguez-Grande Eliana-Isabel , Buitrago-Lopez Adriana , Torres-Narvaez Martha-Rocio , Serrano-Villar Yannely , Verdugo-Paiva Francisca , Ávila Camila
Published: December 2021

Objective: To determine the effect of therapeutic exercises on the motor function of children with Down syndrome (DS) aged 0 to 3 years.Data Sources: A search was carried out on PubMed, PEDro, EMBASE, SCIELO, Lilacs, Cochrane library without publication date restrictions for the terms.Study Selection: The search yielded 1384 eligible articles, which were screened by 2 reviewers. RCTs that would have evaluated the effectiveness of therapeutic exercise were selected, and that would have reported the effectiveness in the outcomes.Data Extraction: The methodology and results of the studies were critically appraised in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes guidelines. Data Synthesis: Six studies were included. Two types of therapeutic exercises, aerobic and neuromuscular, were identified. A therapeutic aerobic exercise was performed using the treadmill, while a neuromuscular exercise was done using unstable surfaces. The exercise frequency ranged from three days to five days a week, and the duration of each session was between six and 15 minutes. Conclusion: There is moderate to high evidence to support that therapeutic exercise promotes the occurrence of motor patterns such as gait patterns and enhances the motor skills of children with DS aged 0 to 3 years.
Development and Validation of an Apoptosis-Related Genes Signature in Patients with Gastric Cancer
Authors: Yang Jianqiao , Shang Liang , Li Leping , Wang Zixiao , Dong Kangdi , Li Han , Liu Jin
Published: December 2021

Background: Gastric cancer (GC) is a common malignant tumour of the digestive tract. the prognosis of GC patients is still not optimistic. Apoptosis-related genes (ARGs) plays an important role in the development, invasion, metastasis and drug resistance of GC. Therefore, assessing the interaction between ARGs and the prognosis of GC patients may help identify specific biomarkers.Methods: Differentially expressed genes (DEGs) were identified by integrating gene expression profiling analyses from The Cancer Genome Atlas (TCGA) GC cohort and Gene Set Enrichment Analysis (GSEA) Database. Then, a risk score model was built based on Kaplan-Meier (K-M), least absolute shrinkage and selector operation (LASSO), and multivariate Cox regression analyses. Another cohort (GSE84426) was used for external validation. By combining risk scores with clinical variables, a nomogram was constructed to predict the prognosis of GC patients. Results: We screened 39 DEGS and established a three-gene signature(CAV1、F2、LUM) based on 161 ARGs. In addition, three-gene signature was identified as an independent factor in predicting the prognosis of GC patients and validated in an external independent cohort. Finally, we developed a nomogram that can be applied to clinical practice.Conclusions: Our study established a three-gene signature of GC based on ARGs that has reference significance for in-depth research on the apoptosis mechanism of GC and the exploration of new clinical treatment strategies.
Sodium citrate-assisted prussian blue analogues as K-rich cathode materials for sodium ion batteries
Authors: li Peng , Gu Genfei , Jiang Yong , Cui Baoyin , Sun Minrui , Zheng Shiyou
Published: December 2021

Prussian blue analogue (PBA), as the cathode material of sodium ion batteries (SIBs), has attracted much attention because of its low price and open three-dimensional channel structure. However, the traditional methods for preparing PBA have high crystallization rate, high water content and many structural defects, which hinder the development of PBA for the application of in batteries. To solve the above problems, in this study, sodium citrate was used to improve the nucleation rate and crystallinity. Herein, PBM1 synthesized by this method not only has good crystallinity and regular particles, but also shows excellent electrochemical performance when used as cathode in SIBs. Under the current density of 0.05A/g, it has a specific capacity of 109.6 mAh/g. At a current density of 0.1A/g, the reversible specific capacity could keep as high as 95.0 mAh/g and with a coulombic efficiency of almost 100% after 300 cycles.
Comparative Transcriptomic Analysis of Two Cucumis Melo Var. Saccharinus Germplasms Differing in Fruit Physical and Chemical Characteristics
Authors: Liang Renfan , Su Yicheng , Qin Xiaojuan , Gao Zhongkui , Fu Zhixin , Qiu Huijun , Lin Xu , Zhu Jinlian
Published: December 2021

Background: Hami melon (Cucumis melo var. saccharinus) is a popular fruit in China noted for its excellent taste, which is largely determined by its physical and chemical characteristics, including flesh texture, sugar content, aroma, and nutrient composition. However, the mechanisms through which the associated with these characteristics are regulated have not yet been sufficiently determined. In this study, we monitored changes in the fruits of two germplasms differing in physical and chemical characteristics throughout the period of fruit development. Results: Ripe fruit of the bred variety ‘Guimi’ had significantly higher soluble sugar contents than the fruit of the common variety ‘Yaolong’, whereas differences in fruit shape and color between these two germplasms were observed during the course of development. Comparative transcriptome analysis, conducted to identify regulators and pathways underlying the observed differences at corresponding stages of development, revealed a higher number of differentially expressed genes (DEGs) in Guimi than in Yaolong. Moreover, most of the DEGs detected during early fruit development of Guimi were associated with cell wall biogenesis. Temporal analysis of the identified DEGs revealed similar trends in the enrichment of downregulated genes in both germplasms, although there were certain differences in the enrichment trends of upregulated genes. Further analyses revealed trends in the differential changes of multiple genes involved in cell wall biogenesis and sugar metabolism during fruit ripening.Conclusions: We were thus able to identify a number of genes associated with the ripening of Hami melon, which will accordingly provide novel insights into the molecular mechanisms underlying the development of fruit characteristics in these melons.
Accurate THz Ellipsometry Using Calibration in Time Domain
Authors: Mazaheri Zahra , Koral Can , Andreone Antonello
Published: December 2021

We report on the realisation of a customized THz Time Domain Spectroscopic Ellipsometer (THz-TDSE) based on fiber-coupled photoconductive antennas, operating in a wide range of incident angles and allowing also standard transmission spectroscopy without any optical realignment. To ensure accurate parameter extraction for a broad range of materials, we developed a fast and effective algorithm-assisted method to calibrate the setup and compensate for the nonideality in the response of the THz system. The procedure allows to minimise errors induced by imperfect response of the antennas and polarizers, imprecise setting of the impinging and receiving angles in the goniometric mechanical arms, and unavoidable mismatches in the THz beam optics. Differently from other calibration methods applied in the literature, our approach compares in time domain the ellipsometric derived electric field s- and p-polarised components at a given angle of incidence with the reconstructed ones, attained by using the complex dielectric function of a known sample. The calibrated response is determined with high precision by setting the system in transmission mode. In order to validate the technique, ellipsometric measurements have been carried out at various angle of incidences on a number of materials both in solid and liquid form, and their data compared with what obtained by conventional THz spectroscopy. Results show that THz-TDSE accompanied with an accurate calibration procedure is an effective technique for material characterization, especially in case of samples with a high absorption rate that are not easily investigated through transmission measurements.
Automated vitrification of cryo-EM samples with controllable sample thickness using suction and real-time optical inspection
Authors: Koning Roman , Vader Hildo , Nugteren Martijn van , Grocutt Peter , Yang Wen , Renault Ludovic , Koster Abraham , Kamp Arnold , Schwertner Michael
Published: December 2021

Speed and efficiency of data collection and image processing in cryo electron microscopy have increased over the last decade. However, cryo specimen preparation techniques have lagged behind and faster, more reproducible specimen preparation devices are needed. Here we present a new vitrification device with highly automated sample handling, requiring only limited user interaction. Moreover, the device allows inspection of thin films using light microscopy, since excess liquid is removed through suction by tubes, not blotting paper. In combination with dew-point control, this enables thin film preparation in a controlled and reproducible manner. The advantage is that quality of the prepared cryo specimen is characterized prior to electron microscopy data acquisition. Practicality and performance of the device are illustrated by experimental results obtained by vitrification of protein suspensions, lipid vesicles, bacterial and human cells, followed by imaged using single particle analysis, cryo electron tomography and cryo correlated light and electron microscopy.
DDPG-Based Continuous Thickness and Tension Coupling Control for the Unsteady Cold Rolling Process
Authors: Zeng Wenying , Wang Jinkuan , Zhang Yan , Han Yinghua , Zhao Qiang
Published: December 2021

Cold rolling is an important part of the iron and steel industry, and the unsteady rolling process of cold rolling usually brings significant influences on the stability of product quality. In the unsteady rolling process, various disturbances and uncertainties such as variable lubrication state, variable equipment working conditions lead to difficulties in the establishment of state space model of thickness and tension, which has become a thorny problem in thickness and tension control. In this paper, we present a model-free controller based on Deep Deterministic Policy Gradient(DDPG), which can continuously control the thickness tension of the unsteady rolling process without the mathematical model. We first formulate the thickness and tension control problem to Markov Decision Process(MDP). We apply strategies such as dividing state space variables with mechanism model, defining reward function and state normalization, the random disturbance and complex uncertainties of unsteady cold rolling process are coped with by utilizing the DDPG controller. In addition, these strategies also ensure the learning performance and stability of the DDPG controller under random disturbance. Simulations and experiments show that the proposed the DDPG controller does not require any prior knowledge of uncertain parameters and can operate without knowing unsteady rolling mathematical models, which has better accuracy, stability and rapidity for thickness and tension in the unsteady rolling process than proportional integral(PI) controller. The artificial intelligence-based controller brings both product quality improvement and intelligence to cold rolling.
Prevalence of Peptic Ulcer Disease and Associated Factors Among Dyspeptic Patients At Endoscopy Unit, University of Gondar Hospital, Northwest Ethiopia
Authors: Assefa Belete , Tadesse Abilo , Abay Zinahebizu , Abebe Alula , Tesfaye Tsebaot , Tadesse Melaku , Lakew Ayenew Molla
Published: December 2021

Background: Dyspepsia is a common complaint in upper gastrointestinal disorders. It is described as predominant epigastric pain lasting for at least one month. Peptic Ulcer Disease (PUD) occurs in 5-15% of patients with dyspepsia. Helicobacter pylori (H.pylori) infection and non-steroidal anti-inflammatory drugs (NSAIDs)/aspirin (ASA) use are widely known risk factors for PUD. This research article aimed to determine the prevalence of PUD and associated factors among dyspeptic patients at the endoscopy unit, University of Gondar hospital, Northwest Ethiopia.Methods: A hospital-based cross-sectional study was conducted at University of Gondar hospital. A sample of 218 adults who presented with the complaint of dyspepsia, and underwent endoscopic evaluation were interviewed from June 1 to November 30, 2020. A consecutive sampling method was used to recruit the study subjects. Relevant clinical history was obtained from patients’ medical records. Upper gastrointestinal endoscopy was used to confirm the presence of peptic ulcer disease. The Data were entered into EpiData version 4.6.0.2 and exported to SPSS version 20 for analysis. Logistic regression analysis was used to identify associated factors with the occurrence of PUD among dyspeptic patients. P-value <0.05 was used to declare a statistically significant association.Results: A total of 218 dyspeptic patients who underwent upper gastrointestinal endoscopic evaluations were included in the study. The PUD was diagnosed in one-third of patients with dyspepsia. Dyspeptic patients with active H. pylori infection (AOR=6.3, 95%CI: 2.96-13.38) and NSAIDs/ASA use (AOR=6.2, 95%CI: 2.93-13.36) were at higher risk of developing PUD.Conclusion: The magnitude of active H. pylori infection among symptomatic PUD patients was high. So then, a “test-and-treat” strategy is advised. Cautious use of NSAIDs/ASA is required as it is readily available over-the-counter.
Solvation Structure and Interfacial Regulation for Extremely Stable Zinc Metal Anodes Operating in a Wide Range of Temperatures
Authors: Xiong Peixun , Kang Yingbo , Yao Nan , Chen Xiang , Zeng Lingxing , Dou Qingyun , Han Xiaotong , Rana Harpalsinh , Tian Zhenchuan , Park Jeong Hee , Zhang Qiang , Park Ho Seok
Published: December 2021

Aqueous zinc-metal batteries are promising for large-scale energy storage owing to their reasonable energy density, safety and low cost. However, their practical applications are limited by hydrogen evolution, corrosion, and dendrite formation of Zn anode and there is trade-off between efficiency and stability at high and low temperatures. Herein, we propose a solvation chemistry regulation strategy that can adjust the Zn2+-solvation structure and in situ form a robust and Zn2+-conducting Zn5(CO3)2(OH)6 SEI on the Zn surface, using hybrid electrolytes of water and a polar aprotic N, N-dimethylformamide. As verified by experimental characterizations and computational analyses, the unique solvation structure and the newly formed solid electrolyte interface are created by hybrid electrolytes, resulting in highly reversible and dendrite-free Zn plating/stripping process as well as thermal stability and high ionic conductivity from −30 to 70 °C. The Zn||Zn symmetric cells in hybrid electrolytes are very stable over 2500 h at 25 ℃ and 2000 h even at –20 ℃. Thus, the stability and reversibility of the hybrid zinc-ion capacitors with Zn metal anode in hybrid electrolytes are firstly achieved in a wide and extreme temperature range, demonstrating high capacity retentions and Coulombic efficiencies over 14000, 10000, and 600 cycles at 25, −20, and 70 ℃, respectively.
Ethical challenges in palliative sedation of adults: protocol for a systematic review of current clinical practice guidelines
Authors: TOMCZYK Martyna , JAQUES Cécile , JOX Ralf J.
Published: December 2021

Introduction:

This study aims to identify the full spectrum of ethical challenges of all forms of palliative sedation for adults as presented in current clinical practice guidelines (CPGs), and to determine whether CPGs specify ethical challenges of this therapy for cancer and non-cancer patients and, if so, how exactly they do this. To the best of our knowledge, no studies have yet investigated this topic. The purpose is purely descriptive; our aim is not to make any kind of normative judgements on these challenges. Nor is our aim to assess the quality of the CPGs.
Methods and analysis

: We will perform a systematic review of CPGs on palliative sedation for adults via five electronic databases, grey literature search tools, citation tracking, and contact with palliative care experts. Current CPGs validated by an international, national, or regional authority, published in English, German, French, Italian, or Polish, from 2000 to the date of the search, will be subjected to content analysis at the textual, linguistic, and thematic levels. This study protocol is reported in accordance with the PRISMA-P criteria and registered on PROSPERO.
Discussion

The results of our systematic review can help raise awareness and understanding of the complexity of ethical problems, rigorously guide reflection in this field, and be useful in elaborating ethical guidelines in an interdisciplinary approach, in order to have a positive impact on the quality of patient care, education and training, and research in respect of this complex and challenging practice.
Maternal Perception of Breastfeeding in Children with Unilateral Cleft Lip and Palate: A Qualitative Research Work
Authors: Cerón-Zapata Ana María , Martínez-Delgado María Cecilia , Calderón-Higuita Gloria Emilia
Published: December 2021

Background : Unilateral cleft lip and / or palate (UCLP) is one of the most common congenital craniofacial difference. The objective of this study was to describe maternal perception of breastfeeding in children with unilateral cleft lip and palate and to assess the role of breastfeeding counseling. Methods : Qualitative descriptive method and phenomenological analysis were used to analyze the narratives. 28 mothers of patients with nonsyndromic UCLP treated with nasoalveolar molding (NAM) between April 2015 and April 2018 were strategically selected and interviewed after NAM treatment. Framework analysis was conducted for qualitative data. The CES University ethical committee approved the study. Results : The findings resulted in six main categories: First contact with the CLP program, access to early diagnosis and timely treatment, perceptions of parents about health personnel on breastfeeding of CLP patients, perceptions of mothers toward breastfeeding, perception of advantages and disadvantages of the NAM technique regarding breastfeeding and assessment of the CLP program. The interviewed mothers, both prenatally and postnatally, stated the advantages of initiating the process prenatally. There are still difficulties for reaching a timely diagnosis. Several mothers stated that health professionals and assistants determined the hospitalization, installation of a nasogastric tube or feeding through a baby bottle or syringe, which prevented the first contact between mother and child. Even though the breastfeeding process is difficult for these mothers, they acknowledged its immense advantages. Interviewed mothers considered the use of the NAM advantageous as the obturator allowed a better bottle-feeding process. The program generates satisfaction, motivation, expectations and happiness to the mothers who initiated this therapy with their children. Conclusion : The participants related difficulties with breastfeeding. Mothers acknowledged the clinical results when using the NAM obturator, as well as the support provided by the breastfeeding consultant.
The Role of Hyperleptinaemia and Low Values of Interleukin 10 in De Novo DSA Production After Kidney Transplantation
Authors: Dedinská Ivana , Kantárová Daniela , Machaleková Katarina , Graňák Karol , Vnučák Matej , Laca Ľudovít , Mokáň Marián
Published: December 2021

Background
White adipose tissue secretes a number of peptide hormones. The aim of this paper was to determine the role of leptin, adiponectin and interleukin-10 and interleukin-6 on the development of graft rejection in protocol biopsy after kidney transplantation.
Methods
In a prospective analysis (n = 104), we monitored the values of leptin, adiponectin, IL-6, and IL-10 prior to the transplantation and in the 3rd month after the transplantation. The protocol biopsy of the graft was performed in the 3rd month after the transplantation. The group was divided into the following according to the biopsy result: negative result, IFTA 1, borderline, and DSA positive.
Results
After adjusting for the differences in the baseline recipient and donor characteristics, we identified the hyperleptinaemia baseline (HR = 2.0444, P = 0.0341) and month 3 (HR = 49.8043, P < 0.0001) as independent risk factors for borderline changes in the protocol biopsy. The hyperleptinaemia baseline (HR = 7.4979, P = 0.0071) and month 3 (HR = 9.7432, P = 0.0057) are independent risk factors for de novo DSA positivity. A low value of IL-10 month 3 is a risk factor for de novo DSA positivity (HR = 3.0746, P = 0.0388).
Conclusions
Higher leptin levels and low values of IL-10 might play a role in rejection and de novo DSA production.
Detection of EGFR Mutation Distribution and Transcriptional Variants in IDH-Wildtype High-Grade Gliomas Using a Next-Generation Sequencing Oncopanel
Authors: Higa Nayuta , Akahane Toshiaki , Hamada Taiji , Yonezawa Hajime , Uchida Hiroyuki , Makino Ryutaro , Watanabe Shoji , Takajo Tomoko , Yokoyama Seiya , Kirishima Mari , Fujio Shingo , Hanaya Ryosuke , Tanimoto Akihide , Yoshimoto Koji
Published: December 2021

\Purpose: To detect the epidermal growth factor receptor gene (EGFR) mutation profile and transcriptional variants in high-grade gliomas (HGGs), we sequenced EGFR and evaluated the EGFR splicing profile using a next-generation sequencing (NGS) oncopanel. Methods: We analyzed 124 HGGs—10 grade Ⅲ IDH-wildtype anaplastic astrocytomas (AAs) and 114 grade Ⅳ IDH-wildtype glioblastomas (GBMs). Results: The EGFR mutations were observed in 6.0% of grade Ⅳ GBMs and in 33% of grade Ⅲ AAs. Four cases harbored missense mutations in the EGFR kinase domain (L747A, S768I, V774M, and T790M). A total of 25% of the GBMs showed EGFR amplification. Moreover, 27% of the EGFR mutations occurred in the kinase domain. EGFRvⅢ positivity was detected in 8.0% of EGFR-amplified GBMs. We identified two other EGFR variants in GBM cases with deletions of exons 6–7 (Δe 6-7) (one case) and exons 2–14 (Δe 2-14) (two cases). Interestingly, in one case, the initial EGFRvIII mutation transformed into an EGFR Δe 2-14 mutation during recurrence. The frequency of EGFR alterations in our cohort was lower but the frequency of EGFR mutations in the kinase domain in our cohort was higher than that in The Cancer Genome Atlas and Memorial Sloan Kettering Cancer Center cohorts. Conclusions: We suggested that the EGFR gene profiles of GBM differ among cohorts and identified rare EGFR variants with longitudinal and temporal transformations of EGFRvⅢ.