bluuebunny/crossref_metadata_2025 huggingface dataset:
Integration of Surface Facilities Constraints with Reservoir Model for Sulphur Production Management in Kashagan Field
Authors: Nogerbek Nurbol , Bukharbayeva Aigerim , Ali Samad , Amangaliyev Bagdad , Shambulov Mustafa , Hatiboglu Can
Published: October 2020

Kashagan oil field has been under production since September 2016. The produced oil is associated with considerable amounts of sour gas that must be processed or disposed of while minimizing flaring. This paper will focus on the methodology for field development planning and production forecasting, incorporating gas reinjection and sulphur management with the objective of optimizing production, subject to operational constraints and bottlenecks at surface facilities.

The field development plan includes reinjection of associated gas into the reservoir to increase oil production capacity at the surface and provide reservoir pressure support, while satisfying government regulations that do not allow continuous gas flaring. This requires analysis of H2S concentration and sulphur production, since the ultimate surface constraint at Kashagan field is sulphur processing capacity.

We describe reservoir modeling workflows for oil production optimization with integrated logic for gas balancing. The impact of sulphur management on oil production is studied under different scenarios using a high resolution, fully compositional reservoir model.

The procedures for management of the production facilities have been translated into reservoir simulation logic, including product streaming from facilities and processing constraints. This includes gas accounting and prioritization of gas with low H2S content to be processed at the sulphur recovery unit. The remaining gas with higher H2S content is sent back to the injection stream.

Workflows have been developed using tailored scripting with user-friendly input of facilities constraints using spreadsheets to enable the model to be maintained in a ‘live’ state. Automatic allocation methods are used for prediction forecasting that penalize higher gas production wells but still provide incremental oil production. Development of a product streaming model allows for reporting of production of liquefied petroleum gas (LPG), dew-pointed gas, etc., in addition to the standard simulation results.

The comprehensive guidelines provided in this paper can aid reservoir modeling and surveillance for a field through accurate analysis of actual operational constraints and bottlenecks as part of the planning process. The described gas and sulphur management logic provide pivotal information to enable the reservoir engineering and production teams to meet the challenges of development planning for a sour reservoir.
IPSM for Production Forecasting and Production Optimization in Giant Carbonate Field Kashagan
Authors: Bukharbayeva Aigerim , Hatiboglu Can , Mtchedlishvili George , Munsyzbayeva Dinara , Uap Berik , Muftakhidinov Baurzhan
Published: October 2020

This paper describes the application of Integrated Production System Modelling (IPSM) at Kashagan field. The IPSM is used for short-term, mid-term production plan and business plan forecasting, opportunity identification/validation and production optimization.

The IPSM modeling strategy is to build fit-for-purpose model which produces accurate results with minimal running time. IPSM enables integration of surface network (GAP) and reservoir simulator through Resolve by Petroleum Experts. This in turn helps to replicate actual field performance by incorporating field management logic (script) and modeling relevant system constraints. While there are many constraints governing the maximum production in Kashagan field, they can be summarized into two main constraints: injection capacity and sulphur processing capacity. Modeling of the latter is essential to consider the impact of composition change over time.

As a result of continuous improvement of existing model and close collaboration with multiple teams, IPSM model has proven its prediction capability with forecast accuracy of 99%. Current IPSM model is able to produce results for various streams: oil & gas production, gas injection, Sulphur throughput, etc.

Additionally, IPSM demonstrated its importance in identification and evaluation of various production opportunities / threats as well as its need in influencing management decisions. After calibration of pipeline network to match actual data, a substantial potential opportunity of optimizing existing wells capacity was revealed. This is vital not only for short-term production optimization needs but also for long-term predictions.

This paper presents several case studies and examples of application and value of Integrated Production System Model in the field. Learnings during implementation of a given feature are also described. Provided examples can be useful for other engineers practicing Integrated Production Model suite.
Development of Young Engineers in a Company Through Organization of Internal Competitions
Authors: Kurmankulov Alikhan , Ramatullayev Samat , Sidorov Dmitry
Published: October 2020

In this paper authors share an experience of one of many ways to foster professional development culture among young engineers through organization of an internal competitions. The competition was held among reservoir engineers working in different locations across the world with a purpose to accelerate and bring to a whole new level their knowledge about one of company flagship software products as well as to use it to solve tough real world industry challenges via application of latest technology and domain knowledge.

The competition was presented in a form of field optimization challenge using new high-fidelity reservoir simulator to give opportunity for everyone interested to learn and uncover simulator's broad and rich functionality. The challenge consisted of two optimization tasks targeting 1) recovery factor and 2) net present value (NPV). There were some field development constraints, such as drilling budget, availability of rig resources, surface facility capability, economic considerations – capital and operating expenditure. The model provided for this challenge represented a synthetic carbonate reservoir that has geological and petrophysical properties inspired by a real carbonate outcrop.

The duration of the challenge was one month. During this period participants tested different field development plan (FDP) scenarios and at the end submitted their solutions. The engagement level among young engineers and creative solutions presented are indicative of a success of this initiative. The competition not only allowed to apply their domain knowledge to tackle real field challenges but also propelled forward their knowledge on advanced features of the simulator.

Rich capabilities of the simulator allowed to implement complex operating logic to manage an asset along with getting hands-on experience designing and optimizing latest technologies such as intelligent completions. On top of that engineers learned to approach a problem from operator's point of view by optimizing capital and operating expenditure – finding a best spot for infill drilling, estimating optimal volume of fluid injection for pressure maintenance, dealing with water breakthrough in production wells and so on. The solutions were evaluated by an organizing committee in each category and winners received special awards. One of the authors of this paper had a privilege to be awarded the highest prize in "NPV optimization task".

Authors will share one many proven effective methods to develop young engineers within a company through engagement and interest to solve industry problems. Also, the paper will provide case studies from the challenge that may spark an interest in industry professionals in reservoir engineering domain along with some differentiating features of new high-fidelity reservoir simulator used in this competition.
Advanced Rod Pump Optimization Approach – Case Study
Authors: Sultabayev Arkhat
Published: October 2020

While most of the operators in Kazakhstan still rely on surface dynocards for rod pump diagnostic, this report shows the value of having pump (calculated) dynocards to obtain production insights. Thanks to mathematical calculations ("wave equation") a dynocard is cleared from all "system noises" and only what is happened at the pump is shown. Advantages of using downhole dynocard are discussed with real wells cases on several Kazakhstan mature fields.
Risk factors for Oil and Gas Workers on the Offshore Ice-Resistant Platform in the Caspian Sea
Authors: Korneeva Yana Aleksandrovna
Published: October 2020

The purpose of the study is to identify and describe uncomfortable factors and environmental conditions, as well as hazardous professional situations for fly-in-fly-out workers of an offshore oil platform in the Caspian Sea. The study was conducted on an ice-resistant offshore platform, the Caspian Sea, and was attended by 50 people (fly-in duration - 14 days). The research method is a questionnaire. The questionnaire developed by us included the following sections: general information about education and work experience; subjective assessment of the discomfort of climatic-geographical, industrial and social factors that affect workers during the fly-in period; subjective assessment of the danger of various situations that may arise during the fly-in period; subjective assessment of the hazard in the workplace and the factors contributing to its formation. As a result of the study, it was found that production factors and the likelihood of emergencies create greater discomfort for employees. In this connection, ensuring safety at the facility is of great relevance for the workers of the offshore oil production platform. Among social and household factors, the first place is the maintenance of relationships with relatives and friends, ensuring the possibility of communication and participation in family life. Positive family relationships, as well as a positive socio-psychological climate in the team are important resources for overcoming the adverse effects of environmental factors.
Waterflood Optimization Planning Based on MRT Analysis of Long-Term Bottom-Hole Pressure Records
Authors: Ganiev Bulat , Lutfullin Azat , Farakhova Rushana , Gulyaev Danila , Zinurov Linar , Aslanyan Arthur
Published: October 2020

In case of brown fields and fields currently undergoing drilling, it is highly important to revise field geology to effectively design pressure support and further refine the existing pressure maintenance system if required. At the same time, the analysis of cross-well interference using Multiwell Retrospective Testing (MRT) is very useful for assessing its effectiveness, and is the main tool, that was used at one of the fields in Tatarstan Republic.

Conventionally to identify the geological structure and assess the reservoir connectivity it is required to use tools that could be quite costly, require expensive field operations and take up a lot of time. These tools include seismic surveys, paleotectonic analysis of the survey zone, tracer surveys and interference tests. Each of these methods comes with well-known disadvantages: weak seismic sensitivity to low-amplitude faults, poor resolution of tectonic analysis, long duration of tracer surveys and their low performance against man-made fractures and inconsistent extension in lateral anisotropy of the reservoir, huge production losses during interference tests due to receiving well shut-ins. In this regard, the MRT technology was chosen as the main tool for assessing pressure support at the brown field. This technology is fully fledged and is currently being implemented at a large-scale, having passed the testing stage on both synthetic and actual fields (Aslanyan, 2019) (Aibazarov, 2019) (Ganiev, 2019) (Kovalenko, 2018) (Krichevsky, 2017). Based on previously collected bottom-hole pressure readings registered during the well production and on production history of a set of analysed wells, the of cross-well interference was restored using multi-well deconvolution algorithms as well as proposals for production increase.

In accordance with the conducted surveys, the reservoir geology was refined, inefficient injectors in terms of pressure support was identified, and it was advised to redistribute the injection to balance it out that will ultimately lead to production increase.
Effect of Pore Size Distribution on Phase Behavior of Sour Gas and Hydrocarbon Mixtures in Tight Oil Reservoirs
Authors: Wang Lei , Ismailova Jamilyam , Uteubayeva Yeldana , Chen Jiaheng , Kunzharikova Klara
Published: October 2020

Carbonate reservoirs in North Caspian Sea region of Kazakhstan produce high concentrations of sour gas or acidic gas species, including H2S and CO2. Effect of sour gas components on phase behavior of hydrocarbon mixtures in these fields needs to be clarified. In addition, some of these reservoir formations are very tight with majority of pores falling in the nanometer range. Therefore, nanoconfinement or capillary effect could play an important role on phase behavior during sour crude oil production and sour gas injection processes.

Gas chromatography was employed to analyze the composition of a live crude oil obtained from a Caspian reservoir and a nanopore system with a pore size distribution (PSD) that is characteristic of tight carbonate reservoirs was set up to regulate the vaporization sequence. Using a flash calculation procedure that incorporates capillary effect, phase behavior of sour crude oil in nanoporous media was studied. Specifically, pressure and temperature (PT) diagrams, constant composition expansion (CCE), constant volume depletion (CVD), and CVD with a critical gas saturation (CGS) were simulated and analyzed.

The live crude oil has an average molecular weight of 56.12 g/mol at bubble point pressure and reservoir temperature, containing 13.32 mol% H2S and 2.90 mol% CO2. PT diagrams showed that the bubble point pressure of sour crude oil is much lower than crude oil analogies that use CO2 and CH4 as substitutes by following the order: H2S<CO2<CH4. Nanoconfinement suppressed liquid vaporization in nanopores in CCE and CVD processes, thus keeping liquid phase at low density and viscosity. Setting a CGS helped expel liquid out of the nanopore system during depletion. CCE and CVD processes indicated that more than 42.0 vol% of the nanopores, including part of the 30 nm and all smaller pores, could be always occupied by liquid phase.

These findings are useful for designing, implementing, and simulating sour crude oil production and sour gas injection processes in tight carbonate reservoirs in the North Caspian Sea region.
Pressure Transient Analysis: Insight from Industry
Authors: Mukanov Adil , Kassenov Duman , Kudalsha Aimurat
Published: October 2020

PKKR JSC operates a couple of dozens of fields with more than a thousand wells. Consequently, a massive wells' surveillance program is conducted which includes pressure transient testing (PTT) and analysis (PTA). It leads to different kinds of cases which, eventually, help us to understand challenging issues. Thus, in the paper we try to shed light on how these data are critical to make the right decision with the aim of getting economical benefits for the company.

Field operation performs PTT on 70-80 wells annually such as pressure buildup and deliverability on producers, pressure falloff on injectors and interference tests on observation wells. All the tests are interpreted by the engineers of the company refusing from service companies during oil price decline in 2015 and purchasing commercial software. Using the software interpreter builds Horner and log-log plots, IPR curve which give the quantitative and qualitative parameters of near the wellbore, undamaged zones and outer boundary conditions. This information coupled with geological and production data are analyzed to gather puzzles into one full picture.

As the result of PTA the company could make important decisions which brought to millions of dollars of savings and earnings. The paper demonstrates standard cases, e.g. a pressure buildup test on a well helped to decide to execute fracturing and multiple time increase in oil rate was obtained. Oppositely, on another well falloff test showed presence of fractures, hereby, planned stimulation measures were cancelled in spite of low injectivity. In addition, falloff tests give additional information on how waterflooding is effectively carried out. Another case which was under active discussion includes the issue of converting a well to water injection, so we conducted an interference test and it reveals no response on adjacent producers. Again the company avoided the wrong decision and waste of money. Moreover, interference tests played a vital role in an extraordinary case where it was unclear how the wells produced gas more than reserves. Unexpectedly, the reason was a communication between two lithologically different reservoirs via fractures. So, it dramatically changed the geological concept of the field. There are other situations when PTA results help to characterize geometry of the reservoirs, presence of faults, their transmissibility, fractures distribution which all are critical for static modeling and dynamic simulation.

PTA is a crucial part of geology and petroleum engineering. It essentially helps engineers and managers to make right decisions. Sometimes it leads to big savings or significant profit earnings due to conducting or avoiding the works. Also PTA can change the geological picture of the whole field if properly analyzed. Thus, it is a powerful tool in the hands of geologists, reservoir and production engineers.
Simulation of Multistage Acid Fractures in Horizontal Well Using Multiple Grid Geometry: Tight Carbonate Reservoir Case
Authors: Volnov Ignatiy , Rojas Danny , Bibolova Assem , Lim Kok-Thye , Amiotte Jerome
Published: October 2020

Multiple methodologies and grid geometries were applied to model the production performance and uncertainties in the planning and execution of a pilot horizontal well with multiple hydraulic fractures. The well is located in a tight carbonate formation and the fracture will be induced hydraulically with acid. A methodology was established to scale the observations of the single well model to a full field scale. This, when calibrated against actual performance from the pilot well, will enable improvements in the planning the development of the target reservoir at full field scale.

The methodologies described in this paper consist of fine grid models to explicitly represent the fractures, a method to calibrate and represent the production performance on a coarse grid full field model.

In the fine grid model, the grid was geometric refined to fracture aperture grid size to capture the physics and flow behavior induced by the acid-fracs. Fracture plane conductivity is based on laboratory measurement of acid-frac experiments. The fine scale model was also used in sensitivity analysis to optimize the pilot well design such as number of fractures and desired fracture height growth, identify risk of water production and help formulate of mitigation strategies.

To enable modeling at full field scale – which is impractical with fine grid models – a novel methodology was established to calibrate a coarse grid field scale model to consistently reproduce the fine grid model behavior. This enables early planning of full field development should the performance of the pilot well support the application of multi acid-frac horizontal well as the preferred technology.
An Overview of Reserves and Resources Evaluation in Unconventionals
Authors: Canbaz Celal Hakan , Temizel Cenk , Ozesen Ahsen , Gayde Simel , Aksahan Firat
Published: October 2020

Reserve/Resource estimation plays a crucial role in a feasible oil and gas business. Tendency of producing more from unconventional reservoirs and their relatively new as well as different structure brought on a learning curve for the applications of new reservoir evaluation methods. This study clearly desribes all reserve and resource evaluation techniques, the latest developments in this area by providing a single-source up-to-date reference for reserves evaluation in unconventionals.

An extensive review of literature has been applied to describe all available reserve evaluation techniques and their utilization, applicability and robustness, the history of using these techniques, types of technologies which applied in conventional reservoirs and transferred to unconventionals, and their incremental benefits of usage.This paper includes a real worldwide case studies which are illustrated with applications, and briefly describes the challenges, drawbacks, also pros and cons case by case. In the end, each case leads to conclusions on the criteria of application of methods as they related to SPE, SEC and PRMS.

In this study, "reserve and resource estimation" of unconventional reservoirs is investigated. The techniques are described by giving their methodology, as well as identifying the crucial parameters and the key factors of the applying procedure for the estimations. For instance, the main key factor of reserves evaluation is consistency and abiding by the rules outlined by SEC, PRMS and other bodies in terms of technical and economic aspects.

Currently, some studies includes the certain examples of reserve evaluation methods in conventional reservoirs, and limited number of works in unconventionals. However, there is no study which is not only outlines the key elements in one study, but also deducts lessons from the real field applications that will shed light on the utilization of the methods in the future applications. This study will close the gap and become a reference study in unconventional oil industry.
Optimization of Well Testing for Current Reserves Estimation with Modern Wireline Formation Testers and Open Hole Logs in Exploration Wells Drilled in High Porosity Sandstone Suprasalt Sediments Field
Authors: Blinov Vladislav , Filimonov Anton , Ramatullaev Samat , Tasemenov Ernur , Saparova Saule
Published: October 2020

In Western Kazakhstan, post-salt high porosity clastic reservoirs of the Caspian Basin of Jurassic and Triassic age are represented by multilayer and multi-contact deposits having several gas-oil (GOC) and oil-water contacts (OWC), formed by channel deposits. Reservoirs have good formation properties. Application of advanced logging suite allows to delineate all the key reservoir properties, such as effective oil-saturated thicknesses, all the types of contacts (GOC, GWC, OWC) along with some other properties. However, in such type of reservoirs, it is important to determine a connectivity of individual lobes/lenses – different small parts of deposits. This can only be achieved via well testing and fluid sampling.

Traditional well testing has long been a must during the exploration stage to obtain vital information on reservoir dynamic properties. Usually, it is rather a tedious and time-consuming process, especially when there are many uncertainties on reservoir fluid saturations that can lead to increased well construction costs. This paper will discuss an example on how to optimize and accelerate well testing stage using advanced wireline formation tester and extended logging methods in an open hole, which, in turn, allows for faster commissioning of reservoirs into production.

It is important to note that wireline formation testers cannot fully replace traditional well testing of wells and reservoirs; however, they significantly expand and improve the capabilities traditional well testing has to offer. Therefore, the most optimal solution proposed by Embamunaigas was the joint use of results of wireline formation tester and traditional well test data in green fields. This workflow has successfully been tested in its license areas in recent years.
Maple Syrup Urine Disease in Brazilian Patients: Variants and Clinical Phenotype Heterogeneity
Authors: Margutti Ana Vitoria Barban , Silva Wilson Araújo , Garcia Daniel Fantozzi , de Molfetta Greice Andreotti , Marques Adriana Aparecida , Amorim Tatiana , Prazeres Vânia Mesquita Gadelha , Silva Raquel Tavares Boy da , Miura Irene Kazue , Neto João Seda , Santos Emerson de Santana , Santos Mara Lúcia Schmitz Ferreira , Lourenço Charles Marques , Tonon Tássia , Sperb-Ludwig Fernanda , de Souza Carolina Fischinger Moura , Schwartz Ida Vanessa Döederlein , Junior José Simon Camelo
Published: October 2020

Background: Maple syrup urine disease (MSUD) is an autosomal recessive inherited metabolic disease caused by deficient activity of the branched-chain α-keto acid dehydrogenase (BCKD) enzymatic complex. BCKD is a mitochondrial complex encoded by BCKDHA, BCKDHB, DBT, and DLD genes. MSUD is predominantly caused by Variants in BCKDHA, BCKDHB, and DBT genes encoding the E1α, E1β, and E2 subunits of BCKD complex, respectively. The aim of this study was to characterize the genetic basis of MSUD by identifying the point variants in BCKDHA, BCKDHB, and DBT genes in a cohort of Brazilian MSUD patients and to describe their phenotypic heterogeneity. It is a descriptive cross-sectional study with 21 MSUD patients involving molecular genotyping by Sanger sequencing. Results: Eight new variants predicted as pathogenic were found between 30 variants (damaging and non-damaging) identified in the 21 patients analyzed: one in the BCKDHA gene (p.Tyr120Ter); five in the BCKDHB gene (p.Gly131Val, p.Glu146Glnfs*13, p.Phe149Cysfs*9, p.Cys207Phe, and p.Lys211Asn); and two in the DBT gene (p.Glu148Ter and p.Glu417Val). Seventeen pathogenic variants were previously described and five variants showed no pathogenicity according to in silico analysis. Conclusion: Given that most of the patients received late diagnoses, the study results do not allow us to state that the molecular features of MSUD variant phenotypes are predictive of clinical severity.
Effectiveness and Tolerability of Repetitive Transcranial Magnetic Stimulation for Preventive Treatment of Episodic Migraine: A Single Centre, Randomised, Double-Blind, Sham-Controlled Phase 2 Trial (Magnet-EM).
Authors: Safiai Nabil Izzaatie Mohamad , Amir Nur Ain , Basri Hamidon bin , Mat Liyana Najwa Inche , Hoo Fan Kee , Khan Abdul Hanif Khan Yusof , Loh Wei Chao , Chia Peck Kee , Ramachandran Vasudevan , Din Hazwan Mat , Samsudin Intan Nureslyna , Fernandez Aaron , Mohamed Mohd Hazmi , Ching Siew Mooi , Hashim Hasnur Zaman , Sulaiman Wan Aliaa Wan
Published: October 2020

Background: This is a phase II randomised, double-blind, sham-controlled trial to evaluate the effectiveness and tolerability of repetitive transcranial magnetic stimulation for preventive treatment of episodic migraine among migraine subjects. Methods: Subjects age 18 to 60 years will undergo a baseline evaluation to establish the diagnosis of migraine based on International Classification of Headache Disorder 3rd Edition (ICHD-3). Those who fulfil the ICHD-3 criteria for episodic migraine and compliant to the headache diary during a month run-in period will be enrolled. A total of 76 subjects will be randomised to receive either transcranial magnetic stimulation or sham stimulation for 5 sessions within 2 weeks duration. Follow-up sessions will be conducted monthly for three consecutive months. Prior to treatment, subjects will be required to fill up questionnaires and undergo few procedures such as electroencephalography, transcranial doppler ultrasound and biochemical analysis for serum serotonin, serum calcitonin-gene related peptide and serum beta-endorphin. These procedures will be repeated at month 3 after receiving last treatment. The primary outcome measure of this study is the difference in mean monthly migraine days at baseline and at month 1, 2 and 3 after treatment sessions. Discussion: Following evidence from previous studies showing restoration of dorsolateral prefrontal cortex (DLPFC) activation to almost normal level, the rTMS intervention will target left DLPFC in this study. An intermediate duration of treatment sessions is selected for this study. It is set to five treatment sessions given within 2 weeks duration. Trial registration: NCT03556722. Transcranial Magnetic Stimulation in Episodic Migraine (Magnet-EM) was registered on 27th April 2018. https://clinicaltrials.gov/ct2/show/NCT03556722.
Neurological and psychological mechanisms of the specific and nonspecific effects of acupuncture on knee osteoarthritis: study protocol for a randomized, controlled, crossover trial
Authors: Li Jin-Ling , Zhang Na , Yan Chao-Qun , Tu Jian-Feng , Wang Li-Qiong , Qi You-Sheng , Liu Jun-Hong , Wang Xu , Liu Cun-Zhi
Published: October 2020

Background: Acupuncture, as one of the promising non-pharmacological interventions, has been proved to be beneficial for patients. However, the magnitude of acupuncture’s specific and nonspecific effects, as well as their neurological and psychological determinants, remain unclear. Therefore, this study is designed to examine the acupuncture efficacy, investigate whether the brain mechanisms between the specific and nonspecific effects of acupuncture are different, and to evaluate how psychological factors affect the acupuncture effects.Methods: This is a randomized, controlled, crossover clinical trial. A total of 60 patients with knee osteoarthritis will receive 4 weeks of acupuncture treatment and 4 weeks of sham acupuncture treatment in a random order separated by a washout period of 2 weeks. The changes in clinical characteristics based on pain-related scales will be assessed to investigate the clinical efficacy of acupuncture. Resting state functional magnetic resonance imaging (fMRI) scans will be used to identify the brain activity changes related to the specific and nonspecific effects of acupuncture. The questionnaires of psychological factors will be used to evaluate patients’ psychological properties. Correlation and mediation analyses will be conducted among psychological factors, brain activity changes and symptoms improvement to explore the neurological and psychological correlates of the acupuncture effects.Discussion: This study will concentrate on distinguishing and clarifying the specific and nonspecific effects of acupuncture. The results of this study may contribute to rationally optimize the acupuncture therapies by flexible application of the specific and nonspecific effects of acupuncture.Trial registration： Chinese Clinical Trial Registry, ChiCTR1900025807, Registered on 9 September 2019, http://www.chictr.org.cn/showproj.aspx?proj=41796)
Indonesian adolescents’ perspectives on smoking habits as a reference for a prevention program: a qualitative study
Authors: fithria fithria , Adlim Muhammad , Jannah Syarifah Rauzatul , Tahlil Teuku
Published: October 2020

Background: The prevalence of smoking among adolescents is high in Indonesia. Therefore, this qualitative research aimed to explore the perspectives of Muslim adolescents on smoking habits as a reference for developing effective prevention programs.Methods: Three focus group discussions involving 24 junior high school students (mean age=13.75 years) were the main source of data for this phenomenological qualitative study. The discussion guide was developed by the researchers based on the reviewed literature and validated by experts. The research findings were analyzed using an inductive content analysis with systematic steps based on the stages of qualitative data analysis.Results: Adolescent perspectives on smoking were grouped into two themes: perception of smoking and smoking-related factors. The perception of smoking encompassed three sub-themes: smoking as a social habit, contradictive feelings, and the Islamic perspective. The smoking-related factors included peer pressure, the parents’ smoking status, masculinity and curiosity. The results indicated that adolescents consider smoking as a social habit but with contradictory feelings. The smoking habit was also stimulated by peer pressure, imitating parents who smoke, feeling masculine and curiosity.Conclusion:. We suggest that health professionals who are interested in developing smoking prevention programs should consider the adolescent perspective on smoking so that the prevention program will be more effective and appropriate for adolescents.
RarERN Path: a methodology towards the optimisation of patients’ care pathways in rare and complex diseases developed within the European Reference Networks
Authors: Talarico Rosaria , Cannizzo Sara , Lorenzoni Valentina , Marinello Diana , Palla Ilaria , Pirri Salvatore , Ticciati Simone , Trieste Leopoldo , Triulzi Isotta , Terol Enrique , Bucher Anna , Turchetti Giuseppe
Published: October 2020

Background In 2017, the European Commission has launched the European Reference Networks (ERNs), virtual networks involving healthcare providers across Europe. The aim of the ERNs is to tackle complex and rare diseases and conditions that require highly specialized treatment and a concentration of knowledge and resources. The ERN on rare and complex connective tissue and musculoskeletal diseases (ERN ReCONNET) is one of the 24 ERNs approved that aims to improve the management of Rare and Complex Connective Tissue and Musculoskeletal Diseases. Objective The RarERN Path methodology aims to create a single reference organisational model for patients’ care pathways which, if applied in different contexts, helps to ensure an improved, cost-effective and patient-centred equal care to rare and complex diseases. Methods Starting from existing standard methods for the creation and elaboration of patients’ care pathways, a specific methodology was created in order to take advantage of the distinctive and peculiar characteristics of the ERNs. Specifically, the development of the RarERN Path methodology involved different stakeholders: health economists, clinicians and researchers expert in rare and complex diseases, communication experts, experts in patients’ involvement and narrative medicine and policy-makers. ResultsThe RarERN Path methodology foresees six consecutive phases, each with different and specific aims. Specifically, the six phases are represented by: Phase 1 - Mapping of existing patients’ care pathways and patients’ stories; Phase 2 – Design of an optimised common patients’ care pathway; Phase 3 – Consensus on an optimised common patients’ care pathway; Phase 4 – Key Performance Indicators (KPI) definition; Phase 5 – Refinement; Phase 6 – Pilot phase (optional).ConclusionThe application of RarERN Path to the different disease-specific and geographical contexts would help to ensure an improved, cost-effective and patient-centred equal care to rare and complex diseases across Europe as well as a possible tangible action towards the integration of ERNs into the different European healthcare systems.
Patterns and patient factors associated with loss to follow-up in the Muhimbili Sickle Cell Cohort, Tanzania
Authors: Masamu Upendo , Sangeda Raphael Zozimus , Kandoga Daniel , Ondego Jesca , Ndobho Florah , Mmbando Bruno , Nkya Siana , Msami Khadija , Makani Julie
Published: October 2020

Background: Monitoring patient's clinical attendance is a crucial means of improving retention in care and treatment programmes. Sickle cell patients' outcomes are improved by participation in comprehensive care programmes, but these benefits cannot be achieved when patients are lost from clinical care. In this study, patients are defined as loss to follow-up when they did not attend clinic for more than nine months. Precise information on the retention rate and characteristics of those who are not following their clinic appointments is needed to enable the implementation of interventions that will be effective in increasing the retention to care. Method: This was a retrospective study involving sickle cell patients registered in the Muhimbili Sickle Cohort in Tanzania. Descriptive and survival analysis techniques both non-parametric methods (Kaplan-Meier estimator and Log-rank test) and semi-parametric method (Cox’s proportional hazard model), were used. A p-value of 0.05 was considered significant to make an inference from the analysis. Results: A total of 5476 patients were registered in the cohort from 2004 to 2016. Of these, 3350 (58.13%) were actively participating in clinics, while 2126 (41.87%) were inactive, of which 1927 (35.19%) were loss to follow-up. We used data from 2004-2014 because between 2015-2016, patients were referred to other government hospitals. From the survival analysis results, pediatric (HR: 14.29,95% CI: 11.0071-18.5768, p <0.001) and children between 5-17 years [HR:2.61,95% CI:2.2324 - 3.0705, p< 0.001] patients were more likely to be loss to follow-up than the adult (18 and above years) patients. It was found that patients with above averages for hematocrit (HR: 2.38, 95% CI: 1.0076 - 1.0404, p=0.0039) or mean cell volume (HR: 4.28, (95% CI: 1.0260 - 1.0598, p<0.001) were more likely to be loss to follow-up than their counterparts. Conclusion: Loss to follow-up is evident in the cohort of patients in long term comprehensive care. It is, therefore, necessary to design interventions that improve patients’ retention. Suggested solutions include refresher training for health care workers and those responsible for patient follow-up on techniques for retaining patients and comprehensive transition programs to prepare patients who are moving from pediatric to adult clinics
Automatic Ventral Intermediate Nucleus Localization Based on Anterior Commissure and Posterior Commissure
Authors: Sarno Riyanarto , Sungkono Kelly Rossa , Rifqi Mohammad Ardika , Fahmi Achmad , Turchan Agus , Bajamal Abdul Hafid
Published: October 2020

The ventral intermediate nucleus (Vim), as the motor thalamic nuclei section, is a generally used target in brain lesion surgery or stimulation for decreasing tremors in people with Parkinson’s disease. Determining the exact position of Vim is challenging because Vim cannot be visualized clearly in commonly used magnetic resonance imaging (MR). Indirect methods, i.e., Coordinate-based targeting and Guiot’s, utilize anterior commissure and posterior commissure to detect the location of Vim. In practice, neurosurgeons manually implement these methods in existing neurosurgical planning software, so the accuracy of the targeting depends on their memory and foresight. Afterward, Coordinate-based targeting and Guiot’s locate Vim based on anterior commissure (AC) and posterior commissure (PC), so neurosurgeons must correctly determine AC and PC. This paper proposes automatic indirect methods and measures the accuracy of indirect methods in MRIs with correct and incorrect orientations of AC-PC planes. An objective of analyzing indirect methods in MRIs with incorrect orientations of AC-PC planes is to discover the most resilient indirect method with inaccuracy AC-PC planes. To develop automatic indirect methods, the first step is redefining the plane passing through three defined points, i.e., AC, PC, and midline reference, by a quaternion. Secondly, Coordinate-based targeting and Guiot’s are implemented to determine the Vim targeting location automatically. This paper converts the rules of those methods in voxels because the rules use millimeters while the three-dimensional MRIs use voxels. The experiment shows that Vim locations obtained by Guiot’s are more accurate than those by Coordinate-based targeting in MRIs with the correct orientation of AC-PC planes. Guiot’s has 0.05 mm smaller value of average error results than Coordinate-based targeting. In contrast, Vim locations based on Coordinate-based targeting are more accurate in the MRIs with the incorrect orientation of AC-PC planes. Coordinate-based targeting has 0.032 mm smaller value of average error results than Guiot’s.
Dietary nutrient intake related to higher grade cervical intraepithelial neoplasia risk: A Chinese population-based study
Authors: Wang Zhe , Yang Aimin , Yang Jing , Zhao Weihong , Wang Zhilian , Wang Wei , Wang Jintao , Song Jinghui , Li Li , Lv Weiguo , Li Dongyan , Liu Huiqiang , Wang Chen , Hao Min
Published: October 2020

Background: Dietary nutrient intake plays a significant role in carcinogenesis. Few studies have investigated the association between dietary nutrient intake and cervical intraepithelial neoplasia (CIN) risk in China. Methods: Data on 2,304 women from an ongoing cohort comprising 40,000 women from China in 2014 were included. We randomly selected 218 out of 2304 people as subjects during 2019. All participants were surveyed through in-person interviews, physical examinations, and laboratory tests. Clinical data were obtained from physical examinations and laboratory tests. Dietary intakes were assessed using a semiquantitative food frequency questionnaire. Nutrition intakes from 26 food sources were calculated using a comprehensive validated database. Descriptive statistics were used to describe the frequency and proportion, and mean and standard deviation of the demographic characteristics. Characteristics were examined for significant differences, and Pearson chi-square tests were used for categoric variables. Logistic regression was used to obtain odds ratios (ORs) and confidence intervals (CIs) for CIN risk in each nutritional ingredient quartile relative to that in the highest quartile. Results: The food frequency questionnaire exhibited acceptable reproducibility and reasonable validity in assessing nutrient intakes among these women. After adjusting for multiple confounders, several dietary nutrients showed significant associations with CIN2+ risk. Low dietary folate intake was associated with the risk of CIN2+ (first versus fourth quartile: OR=1.55, 95% CI: 1.03-2.33). Similar results were also observed for vitamin B6 (OR=1.63, 95% CI: 1.08-2.46), vitamin C (OR=1.59, 95% CI: 1.05-2.42), niacin (OR=1.65, 95% CI: 1.08-2.51), and vitamin K (second versus fourth quartile: OR=1.60, 95% CI: 1.05-2.44).Conclusions: Low folate; vitamin B6, C, and K; and niacin intakes were associated with CIN2+ risk. Nutrients may influence the development of higher grade CIN and cervical cancer.Trial registration: The study was registered in the Chinese Clinical Trial Register (ChiCTR-ROC-15006479) (http://www.chictr.org.cn).
Phase II study of sequential S-1 and cyclophosphamide therapy in patients with metastatic breast cancer
Authors: Yanai Keiko , Fujii Takaaki , Horiguchi Jun , Nakazawa Yuko , Kurozumi Sasagu , Obayashi Sayaka , Yajima Reina , Shirabe Ken
Published: October 2020

Background: S-1 and cyclophosphamide (CPA) can be given orally, and their combination may have great potential for treating metastatic breast cancer (MBC). A phase I study of sequential S-1 and CPA therapy was conducted in patients with MBC; the recommended doses that were determined for this regimen were 80 mg/m2/day for S-1 and 100 mg/m2/day for CPA. We then conducted a phase II study of this oral S-1 and CPA regimen.Methods: This was a single-arm, open-label, single-center prospective phase II study to evaluate the efficacy of a sequential S-1 and CPA regimen for MBC. S-1 was administered orally 2´/day for 14 consecutive days, and then CPA was administered orally 2´/day for 14 consecutive days in a repeating 4-week cycle (S-1 for 2 weeks, CPA for 2 weeks). The primary endpoint was the overall response rate (ORR). Secondary endpoints included the overall survival (OS), progression-free survival (PFS), clinical benefit rate (CBR) and safety.Results: Thirty-six patients were enrolled in this study. The overall response was complete response in 0 (0%), partial response in 12 (33.3%), stable disease in 12 (33.3%), and progressive disease in 11 (30.1%) patients. The ORR was 33.3% (12/36). The CBR was 66.7% (24/36). The median PFS was 9.5 months (95%CI: 7.8–12.6 months). The median OS was 20.2 months (95%CI: 15.0–25.4 months) Grade 3/4 adverse events included leukopenia in seven patients (19.4%). Dose reductions because of adverse events occurred in 12 patients (33.3%). There was no treatment-related mortality. Conclusion: The combination of sequential therapy with S-1 and CPA was tolerable and had efficacy with good disease control. Sequential therapy with S-1 and CPA may be a feasible new treatment option for patients with MBC; however, further study is warranted to explore the efficacy of this therapy.Trial registration: JRCT, JRCTs 031180296. Registered 2 December 2019 – Retrospectively registered, https://jrct.hiph.go.jp/latest-detail.jrcts031180296
Enhanced aging and thermal shock performance of Mn1.95-xCo0.21Ni0.84SrxO4 NTC ceramics
Authors: Li Haibing , Zhang H.M. , Thayil Islla P Ley , Chang Aimin , Sang Xu , Ma Xiuhua
Published: October 2020

Abstract: Herein, the Mn1.95-xCo0.21Ni0.84SrxO4 (MCNS) (0 ≤ x ≤ 0.15) based negative temperature coefficient (NTC) materials are prepared by co-precipitation method. The replacement of Mn by Sr plays a critical role in controlling the lattice parameter, relative density, microstructure and electrical properties. The lattice parameter and relative density increase with the increase of Sr content. A small amount of Sr restrains the grain growth and increases the bulk density. Moreover, the ρ25, B25/50, Ea and α values of MCNS ceramics are influenced by the Sr content and ranged from 1535.0-2053.6 Ω·cm, 3654-3709 K, 0.3149-0.3197 eV and -4.111--4.173%, respectively. The XPS results explain the transformation of MCNS ceramics from n- to p-type semiconductors. The conduction could arise from the hopping polaron between Mn3+/Mn4+ and Co2+/Co3+ in the octahedral sites. The impedance data analysis also discussed the conduction mechanism of the MCNS ceramic, while grain resistance dominates the whole resistance of the samples. Furthermore, the aging coefficient (△R/R) of MCNS ceramics is found to be < 0.2%, which indicates the stable distribution of cations in the spinel. Finally, the MCNS ceramics demonstrate excellent thermal durability with <1.3% of resistance shift after 100 thermal shock cycles.
Validation of APACHE II, APACHE III and SAPS II scores in in-hospital and one year mortality prediction in a mixed intensive care unit in Poland: a cohort study
Authors: Czajka Szymon , Ziębińska Katarzyna , Marczenko Konstanty , Posmyk Barbara , Szczepańska Anna , Krzych Łukasz
Published: October 2020

Background. There are several scores used for in-hospital mortality prediction in critical illness. Their application in a local scenario requires validation to ensure appropriate diagnostic accuracy. Moreover, their use in assessing post-discharge mortality in intensive care unit (ICU) survivors has not been extensively studied. We aimed to validate APACHE II, APACHE III and SAPS II scores in short- and long-term mortality prediction in a mixed adult ICU in Poland. APACHE II, APACHE III and SAPS II scores, with corresponding predicted mortality ratios, were calculated for 303 consecutive patients admitted to a 10-bed ICU in 2016. Short-term (in-hospital) and long-term (12-month post-discharge) mortality was assessed. Results. Median APACHE II, APACHE III and SAPS II scores were 19 (IQR 12-24), 67 (36.5-88) and 44 (27-56) points, with corresponding in-hospital mortality ratios of 25.8% (IQR 12.1-46.0), 18.5% (IQR 3.8-41.8) and 34.8% (IQR 7.9-59.8). Observed in-hospital mortality was 35.6%. Moreover, 12-month post-discharge mortality reached 17.4%. All the scores predicted in-hospital mortality (p<0.05): APACHE II (AUC=0.78; 95%CI 0.73-0.83), APACHE III (AUC=0.79; 95%CI 0.74-0.84) and SAPS II (AUC=0.79; 95%CI 0.74-0.84); as well as mortality after hospital discharge (p<0.05): APACHE II (AUC=0.71; 95%CI 0.64-0.78), APACHE III (AUC=0.72; 95%CI 0.65-0.78) and SAPS II (AUC=0.69; 95%CI 0.62-0.76), with no statistically significant difference between the scores (p>0.05). The calibration of the scores was good. Conclusions. All the scores are acceptable predictors of in-hospital mortality. In the case of post-discharge mortality, their diagnostic accuracy is lower and of borderline clinical relevance. Further studies are needed to create scores estimating the long-term prognosis of subjects successfully discharged from the ICU.