bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Novel Workflow for Optimizing Well Placement Under Geomechanical Constraints: A Case Study
Authors: An Cheng , Zhang Peng , Wesley Amanveer , Bardy Gaetan , Hall Kevin , Erdogan Meftun 
Published: August 2020

Abstract
A novel workflow to optimize well placement using geomechanical constraints is introduced to maximize production performance, reduce excessive simulation runs, and minimize drilling constraints by considering the local stress field and the petrophysical properties in a given reservoir. A case study is presented for optimization of horizontal well placement in the Monterey Formation of Miocene Age in California. First, a three-dimensional reservoir model of formation pressure, in situ stresses, petrophysical and rock properties were built from available petrophysical and well log data. Second, numerical modeling using material point method (MPM) was applied to generate the differential stress field, taking into consideration a three-dimensional natural fracture network in the reservoir model. Third, an optimization algorithm which incorporates petrophysical properties, natural fracture distribution, differential stresses, and mechanical stability was used to identify the best candidate locations for well placement. Finally, flow simulations were conducted to segregate each candidate location where both natural and hydraulic fractures were considered. Statistical methods identify optimal well positions in areas with low differential stress, high porosity, and high permeability. Several candidate locations for well placement were selected and flow simulations were conducted. A comparison of the production performance between the best candidates and other randomly selected well configurations indicates that the workflow can effectively recognize scenarios of optimum well placement. The proposed workflow provides practical insight on well placement optimization by reducing the number of required reservoir simulation runs and maximizing the hydrocarbon recovery.
Effect of Argon Concentration on Laminar Burning Velocity and Flame Speed of Hydrogen Mixtures in a Constant Volume Combustion Chamber
Authors: Morovatiyan Mohammadrasool , Shahsavan Martia , Aguilar Jonathan , Mack J. Hunter 
Published: August 2020

Abstract
Hydrogen combustion, coupled with the use of argon as a working fluid, is a promising approach to delivering clean and efficient energy from internal combustion (IC) engines. The use of hydrogen-oxygen-argon (H2/O2/Ar) mixtures in combustion aids in mitigating harmful environmental pollutants and enables a highly efficient energy conversion process. The use of argon as a working fluid decreases the NOx emissions and increases the thermal efficiency of internal combustion engines due to the high specific heat ratio of noble gases. In this study, premixed hydrogen combustion was investigated with the purpose of examining the effect of the full or partial substitution of argon for nitrogen in air on laminar burning velocity (LBV), flame speed, flame morphology, and instability. The experimental approach uses an optically accessible constant volume combustion chamber (CVCC) with central ignition; the spherical flame development was studied using a high-speed Z-type Schlieren visualization system. Moreover, a numerical model was developed to convert the experimental dynamic pressure rise data to laminar burning velocity. Coupling the model to a chemical equilibrium code aids in determining the burned gas properties. Additionally, an image processing technique has been suggested to compute the flame propagation speed. The experimental and numerical investigations indicate that increasing the concentration of argon as the working fluid in the mixture increases the laminar burning velocity and flame speed while extending the lean flammability limit.
Evaluating the Effects of Transient Purge Flow on Stator-Rotor Seal Performance
Authors: Berdanier Reid A. , DeShong Eric T. , Thole Karen A. , Robak Christopher 
Published: August 2020

Abstract
As modern engine designs target higher efficiencies through increased turbine inlet temperatures, critical turbine components are at increased risk of damage from conditions exceeding material melting temperatures. In particular, improperly designed underplatform hardware components are susceptible to damage when hot main gas path flow is ingested into the stator-rotor cavity. While all turbines inherently experience transients during operation, a majority of publicly available turbine studies have been executed using steady operating conditions or inherently transient “blowdown” rigs. For this reason, routine transient events are not well understood. To address this need, the present study utilized a combined experimental and computational approach. The test article is a continuous-duration, one-stage test turbine operating with true-scale engine hardware and seal geometries at engine-representative flow conditions. The nature of the continuous-duration facility uniquely supports the direct assessment of transient events through its ability to transition between steady-state operating conditions. The effects of a transient purge flow were investigated in this study to identify general trends for transient events in a full-scale engine. Results from multiple measurement techniques in the wheelspace region show an interdependence of transient purge flow with a thermal lag of the underplatform hardware. Through experiments conducted at different coolant-to-main gas path temperature ratios, the use of pressure measurements as an indicator of fully purged behavior was introduced, and a thermally driven influence on rim seal performance was quantified. The computational results show good agreement with experimental pressure measurements and provide insight into the physical mechanisms that drive the relationship between pressure and sealing effectiveness measurements observed for the tested geometry.
Venipuncture activates the cerebral cortex in children with intellectual disability
Authors: Bembich Stefano , Morabito Giuliana , Simeon Valentina , Strajn Tamara , Rutigliano Rosaria , Di Rocco Paola , Cont Gabriele , Risso Francesco Maria , Peri Francesca , Barbi Egidio 
Published: August 2020

ObjectiveTo evaluate the pattern of cortical activation during a painful procedure, such as a venipuncture, in children with intellectual disability and compare it with that of cognitively healthy children.Study design and settingA cohort study was conducted and cortical activation was assessed by multichannel cerebral near-infrared spectroscopy to monitor variations in oxyhaemoglobin and deoxyhaemoglobin (Hbb) in children with and without intellectual disability during a venipuncture for blood sampling with topical anaesthesia. Pain and distress were assessed as well using different validated pain scales (visual analogue scale and Non-Communicating Children’s Pain Checklist-Postoperative Version for children with intellectual disability), and compared between groups.Participants16 children with severe to profound intellectual disability and 20 cognitively healthy peers (age range: 4–17 years).ResultsWhen Hbb was analysed, children with intellectual disability exhibited a bilateral activation of the somatosensory (p<0.006) and right motor cortex (p=0.0045), whereas cognitively healthy peers never showed a cortical activation. Children with intellectual disability also showed more pain than controls (p=0.001).ConclusionsWhen subjected to a painful procedure, only children with intellectual disability show an activation of the cerebral cortex, even if topical anaesthesia is applied, and express more pain than cognitively healthy peers. The role of other issues in painful procedures, such as anxiety, fear or physical restraint, deserves further investigation.
Factors associated with blindness three months following treatment for acute
primary angle glaucoma
Authors: Li Shuning , Tang Guangxian , Fan Su Jie , Zhai Gang , Lv Jianhua , Zhang Hengli , Lu Wensheng , Jiang Jing , Lv Aiguo , Wang Ningli , Cao Kai , Zhao Jing , Vu Vivian , Mu Dapeng , Pan Xiaohua , Feng Hui , Hsia Yen C , Han Ying 
Published: August 2020

Aims
To study the risk factors associated with blindness after treatment of
acute primary angle closure (APAC), and to identify the critical time window to
decrease rate of blindness.

Methods
In this multicentre retrospective case series, 1030 consecutive subjects
(1164 eyes) with APAC in China were recruited. The rates of blindness were
analysed up to 3 months after treatment of APAC. A logistic regression was used
to identify the risk factors associated with blindness, including age, gender,
distance to hospital, rural or urban settings, treatment method, education
level, time from symptom to treatment (TST, hours) and presenting intraocular
pressure (IOP). The critical time window associated with a blindness rate of
≤1% was calculated based on a cubic function by fitting TST to the rate of
blindness at each time point.

Results
The rate of blindness after APAC was 12.54% after treatment. In
multivariate regression, education level, TST and presenting IOP were risk
factors for blindness (p=0.022, 0.004 and 0.001, respectively). The critical
time window associated with a blindness rate of ≤1% was 4.6 hours.

Conclusions and relevance
Education level, TST and presenting IOP were risk factors for blindness
after APAC. Timely medical treatment is key in reducing blindness after
APAC.
Prevalence and incidence of HIV among female sex workers and their clients: modelling the potential effects of intervention in Rwanda
Authors: Nsanzimana Sabin , Mills Edward J , Harari Ofir , Mugwaneza Placidie , Karita Etienne , Uwizihiwe Jean Paul , Park Jay JH , Dron Louis , Condo Jeanine , Bucher Heiner , Thorlund Kristian 
Published: August 2020

BackgroundRwanda has identified several targeted HIV prevention strategies, such as promotion of condom use and provision of antiretroviral therapy (ART) and pre-exposure prophylaxis (PrEP) for female sex workers (FSWs). Given this country’s limited resources, understanding how the HIV epidemic will be affected by these strategies is crucial.MethodsWe developed a Markov model to estimate the effects of targeted strategies to FSWs on the HIV prevalence/incidence in Rwanda from 2017 to 2027. Our model consists of the six states: HIV-; HIV+ undiagnosed/diagnosed pre-ART; HIV+ diagnosed with/without ART; and death. We considered three populations: FSWs, sex clients and the general population. For the period 2017–2027, the HIV epidemic among each of these population was estimated using Rwanda’s demographic, sexual risk behaviour and HIV-associated morbidity and mortality data.ResultsBetween 2017 and 2027, with no changes in the current condom and ART use, the overall number of people living with HIV is expected to increase from 344,971 to 402,451. HIV incidence will also decrease from 1.36 to 1.20 100 person-years. By 2027, a 30% improvement in consistent condom use among FSWs will result in absolute reduction of HIV prevalence among FSWs, sex clients and the general population by 7.86%, 5.97% and 0.17%, respectively. While recurring HIV testing and improving the ART coverage mildly reduced the prevalence/incidence among FSWs and sex clients, worsening the two (shown by our worst-case scenario) will result in an increase in the HIV prevalence/incidence among FSWs and sex clients. Introduction of PrEP to FSWs in 2019 will reduce the HIV incidence among FSWs by 1.28%.ConclusionsContinued efforts toward improving condom and ART use will be critical for Rwanda to continue their HIV epidemic control. Implementing a targeted intervention strategy in PrEP for FSWs will reduce the HIV epidemic in this high-risk population.
Latent safety threat identification during in situ simulation debriefing: a qualitative analysis
Authors: Shah Sparsh , McGowan Melissa , Petrosoniak Andrew 
Published: August 2020

BackgroundLatent safety threats (LSTs) in healthcare are hazards or conditions that risk patient safety but are not readily apparent without system stress. In situ simulation (ISS), followed by post-scenario debriefing is a common method to identify LSTs within the clinical environment. The function of post-ISS debriefing for LST identification is not well understood.ObjectivesThis study aims to qualitatively characterise the types of LSTs identified during ISS debriefing.MethodsWe conducted 12 ISS trauma scenarios followed by debriefing at a Canadian, Level 1 trauma centre. We designed the scenarios and debriefing for 15 and 20 min, respectively. Debriefings focused on LST identification, and each session was audio recorded and transcribed. We used an inductive approach with qualitative content analysis to code text data into an initial coding tree. We generated refined topics from the coded text data.ResultsWe identified five major topics: (1) communication and teamwork challenges, (2) system-level issues, (3) resource constraints, (4) positive team performance and (5) potential improvements to the current systems and processes.ConclusionsDuring simulation debriefing sessions for LST identification, participants discussed threats related to communication and interpersonal issues. Safety issues relating to equipment, processes and the physical space received less emphasis. These findings may guide health system leaders and simulation experts better understanding of the strengths and limitations of simulation debriefing for LST identification. Further studies are required to compare ISS-based LST identification techniques.
Risk factors for fatal drowning in a Greek region: a retrospective case–control study
Authors: Kevrekidis Dimitrios Phaedon , Brousa Evdokia , Mastrogianni Orthodoxia , Orfanidis Amvrosios , Gika Helen G , Raikos Nikolaos 
Published: August 2020

BackgroundFatal drowning is one of the leading causes of unintentional injury mortality worldwide and a persistent public health concern in Greece. While several pathologic and sociodemographic contributing factors have been previously identified, these have not been extensively investigated in conjunction with the effects of psychoactive substances.MethodsA retrospective case–control study of drowning deaths was conducted in the Greek regions of Northern Greece and Thessaly during a 10-year period. A regression model was constructed examining differences in detected substances, autopsy findings and sociodemographic characteristics between 240 victims of unintentional fatal submersion and 480 victims of other causes of sudden or violent death.ResultsThe majority of victims were males (69.4%) and foreign nationality was associated with increased odds of drowning. Cardiomegaly and coronary bypass grafts were significantly more likely to have been recorded among drowning victims, while the frequency of other circulatory system disorders was also elevated. Several of these findings were potential arrhythmogenic substrates which could adversely interact with the diving reflex. Selective serotonin reuptake inhibitors (SSRIs) were the most commonly detected pharmacological group (9.0%), and along with tramadol, there was an increased likelihood of exposure to them. These drugs have been previously associated with QT prolongation and other adverse effects which may contribute to fatal outcomes in a seawater environment. In contrast, there was a decreased risk of exposure to dependence-inducing drugs and paracetamol.ConclusionsMale sex, older age, foreign nationality and cardiovascular disease predisposed individuals to an elevated risk of fatal submersion. SSRI antidepressants and tramadol may contribute to this outcome.
Airborne occupational exposures and inflammatory biomarkers in the Lifelines cohort study
Authors: Faruque Md. Omar , Vonk Judith M. , Bültmann Ute , Boezen H. Marike 
Published: August 2020

IntroductionInflammatory biomarkers are associated with negative health outcomes. In this study, we investigated the associations between airborne occupational exposures and levels and changes in inflammatory biomarkers.MethodsWe included 79 604 adults at baseline from the Lifelines cohort of which 48 403 (60.8%) subjects were followed for a median of 4.5 years. Airborne occupational exposures at the current or last-held job at baseline were estimated with the occupational asthma-specific job-exposure matrix. Both in cross-sectional and longitudinal analyses, we used linear regression models (adjusted for age, sex, education, monthly income, body mass index, smoking, pack-years, asthma and anti-inflammatory medication) to investigate the associations between airborne occupational exposures (allergens, reactive chemicals, pesticides and micro-organisms) and inflammatory biomarkers (C reactive protein (CRP), eosinophils and neutrophils).ResultsIn the cross-sectional analyses, exposure to allergens, reactive chemicals and micro-organisms was associated with a lower (Log) CRP level (B(95% CI)=−0.05 (−0.08 to −0.02),–0.05(−0.08 to −0.02) and −0.09(−0.16 to −0.02), respectively). Likewise, exposure to allergens, reactive chemicals, pesticides and micro-organisms was associated with a lower (log) neutrophils count (−0.01 (−0.02 to −0.01), −0.01 (−0.02 to −0.01),–0.02 (−0.04 to −0.01) and −0.02(−0.03 to −0.01), respectively). No association between airborne occupational exposures and eosinophils count was found. In the longitudinal analyses, no association between airborne occupational exposures and changes in inflammatory biomarkers was found.ConclusionsAt baseline, airborne occupational exposures are inversely associated with inflammation; no effect of occupational exposures on inflammation was found at follow-up. In the future studies, details of occupational exposures, such as duration of exposures and cumulative exposures, need to be included to investigate the airborne occupational exposures and inflammatory biomarkers.
Echocardiographic diagnosis of right-to-left shunt using transoesophageal and transthoracic echocardiography
Authors: Lee Mirae , Oh Ju Hyeon 
Published: August 2020

BackgroundThe diagnosis and quantification of right-to-left shunt (RLS) using transthoracic echocardiography (TTE) as well as transoesophageal echocardiography (TOE) have not been well established. We aimed to diagnose RLS by TOE using direct visualisation of the shunt and to compare the diagnosis with TTE diagnosis using conventional methods.Methods and resultsWe evaluated 141 patients with ischaemic stroke for RLS by both non-sedation TOE and TTE using saline contrast and Valsalva manoeuvre. The amount (graded as 0 to IV) and timing of RLS were demonstrated. All patients were classified into four groups by TOE based on direct visualisation of shunt through a patent foramen ovale (PFO) or either pulmonary vein: no shunt (group 1: n=11), PFO (group 2: n=47), pulmonary RLS (group 3: n=25) and indeterminate RLS (group 4: n=58). All cases in group 3 showed delayed shunt, and all cases in group 4 had small shunt. On TTE findings, all cases with early appearing large shunt (cardiac cycles ≤3 and shunt grade ≥III) were group 2. Six of the eight patients with delayed appearing large shunt on TTE were group 3. TTE diagnosis of PFO using criteria of cardiac beats ≤3 and grade ≥II had a sensitivity of 85% and a specificity of 98% compared with TOE diagnosis using shunt visualisation.ConclusionsCompared with TOE using shunt visualisation, TTE accurately diagnosed large PFO using criteria of cardiac cycles ≤3 and shunt grade ≥III. TTE possibly diagnosed pulmonary shunt using criteria of cardiac cycles >3 and shunt grade ≥III. Both modalities showed limitations in diagnosing small amount of RLS.
Left ventricular mass and myocardial scarring in women with hypertensive disorders of pregnancy
Authors: Quesada Odayme , Park Ki , Wei Janet , Handberg Eileen , Shufelt Chrisandra , Minissian Margo , Cook-Wiens Galen , Zarrini Parham , Pacheco Christine , Tamarappoo Balaji , Thomson Louise E J , Berman Daniel S , Pepine Carl J , Bairey Merz Noel 
Published: August 2020

AimsHypertensive disorders of pregnancy (HDP) predict future cardiovascular events. We aim to investigate relations between HDP history and subsequent hypertension (HTN), myocardial structure and function, and late gadolinium enhancement (LGE) scar.Methods and resultsWe evaluated a prospective cohort of women with suspected ischaemia with no obstructive coronary artery disease (INOCA) who underwent stress/rest cardiac magnetic resonance imaging (cMRI) with LGE in the Women’s Ischemia Syndrome Evaluation-Coronary Vascular Dysfunction study. Self-reported history of pregnancy and HDP (gestational HTN, pre-eclampsia, toxaemia and eclampsia) were collected at enrollment. In our cohort of 346, 20% of women report a history of HDP. HDP history was associated with 3.2-fold increased odds of HTN. Women with a history ofbothHDP and HTN had higher cMRI measured left ventricular (LV) mass compared with women with HDP only (99.4±2.6 g vs 87.7±3.2 g, p=0.02). While we found a similar frequency of LGE scar, we observed a trend towards increased LGE scar size (5.1±3.4 g vs 8.0±3.4 g, p=0.09) among the women with HDP history compared to women without.ConclusionIn a high-risk cohort of women with suspected INOCA, 20% had a history of HDP. Women with HDP history were more likely to develop HTN. Our study demonstrates higher LV mass in women with HDP and concomitant HTN. Although the presence of LGE scar was not different in women with and without HDP history, we observed a trend towards larger scar size in women with HDP. Future studies are needed to better assess the relationship of HDP and cardiac morphology and LGE scarring in a larger cohort of women.
Why Tasmanian retailers stop selling tobacco and implications for tobacco control
Authors: Melody Shannon M , Martin-Gall Veronica A , Veitch Mark G 
Published: August 2020

IntroductionThe retail availability of tobacco is at odds with the health harms associated with tobacco smoking and undermines tobacco control efforts. Evidence suggests ease of access to tobacco through retail outlets contributes to smoking prevalence.ObjectiveThis study aimed to understand why retailers stop selling tobacco and explore possible implications for tobacco control.MethodsThe Tobacco Licensing Database maintained by the Department of Health Tasmania was used to identify and recruit past retailers who no longer held licences. Semistructured interviews were conducted to explore business demographics and the reasons they stopped selling tobacco. Interview findings were analysed using a thematic framework.ResultsTwenty former tobacco retailers participated, representing all business types except specialist tobacconists and large supermarkets. Retailers gave multiple reasons for ending tobacco sales, related to business considerations, security, tobacco regulations, ethics and health. Most often, the decision was business-related; health or ethical considerations were rarely a factor. Most retailers felt they played no role in mitigating tobacco-related harm.ConclusionsThis study provides insights into factors that make tobacco sales unattractive or unfeasible for low-volume outlets and may inform supply-focused tobacco control policy. A campaign that emphasises the possible business benefits of ending tobacco sales in favour of other higher-margin products may support retailers to transition away from tobacco sales. The regulatory obligations of selling tobacco are disincentives and create a less favourable retail environment.