bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular structure and vibrational spectra of 2-(4-bromophenyl)-3-(4-hydroxyphenyl) 1,3-thiazolidin-4-one and its selenium analogue: Insights using HF and DFT methods
Authors: Kavitha Helen P. , Rhyman Lydia , Ramasami Ponnadurai 
Published: October 2018

Abstract
2-(4-Bromophenyl)-3-(4-hydroxyphenyl)-1,3-thiazolidin-4-one and its selenium analogue were studied in the gas phase using HF and DFT methods. The functionals considered were B3LYP, BP86 and M06. The basis set for all the atoms was 6-311++ G(d,p). Molecular parameters such as bond lengths, bond angles, rotational constants, dipole moments, electronic energies, and vibrational parameters namely harmonic vibrational frequencies and relative intensities were computed for these compounds. Atomization energies, HOMO-LUMO gaps and natural charges on the atoms were also calculated. The molecular parameters and the vibrational spectra of sulfur compound are in good agreement with the experimental data. Therefore, the data for the selenium analogue should be helpful in its future characterization.
A prospective study of patients’ pain intensity after cardiac surgery and a qualitative review: effects of examiners’ gender on patient reporting
Authors: Meyer-Frießem Christine H. , Szalaty Patrycja , Zahn Peter K. , Pogatzki-Zahn Esther M. 
Published: October 2018

Abstract

Background and aims
As indicated by experimental studies, reports of pain intensity may depend on the examiner’s gender. Until now, it is unclear whether this is relevant in clinical routine. This study investigated prospectively whether the gender of assessor plays a role in patients’ pain reports and whether this role differs in male and female patients.

Methods
165 patients (66.4 years±0.63; 118 males) scheduled for heart surgery were allocated consecutively to one examiner out of four students of both genders: two females and two males (aged 24.3 years±1.7). Therefore, the following study groups were defined: Group 1: female assessors-female patients, 2: female-male; 3: male-female, 4: male-male. Using a standardized analgesic scheme, patients were asked to rank their pain intensity on a numeric rating scale (NRS: 0–10), postoperatively. Statistics: Kruskal-Wallis, Mann-Whitney; p<0.05. Additionally, a qualitative literature review of the databases Medline and CENTRAL was performed focusing on experimental and clinical studies on experimenter gender bias. Due to the review, this prospective clinical study was designed to investigate whether patients after surgery report lower pain intensities when assessed by a female compared to a male assessor.

Results
Summarizing all patients, pain intensity on POD_1 was rated 4.0±2.4 on NRS and decreased on POD_2 to 3.0±2.1 [H(3)=37.941, p=0.000]. On average, pain intensity did not differ between males and females (NRS: 3.5 vs. 3.6). Only on the second postoperative day, more intense pain was reported in front of female assessors and less intense pain in front of male assessors (NRS: 3.4 vs. 2.4; p=0.000). A main effect for the four groups was seen (p=0.003): male patients reported higher pain scores to female assessors (NRS: 3.5 vs. 2.3; p=0.000).

Conclusions
Together, contrary to the expectations, patients after cardiac surgery reported a higher pain intensity in front of a female and a lower pain intensity in front of a male assessor. In particular, female caregivers may heighten the reported pain intensity up to 1.2 NRS-points; this bias seems to be more relevant for male patients.

Implications
Therefore, despite some methodological weakness, our data suggest that attention should be paid to a rather small, but somehow significant and consistent examiner gender bias after cardiac surgery especially in male patients. Further clinical studies are needed to show the true extent of clinical relevance and exact mechanisms underlying these gender reporting bias.
The Echocardiography Quality Framework: a comprehensive, patient-centered approach to quality assurance and continuous service improvement
Authors: Masani Navroz 
Published: October 2018

Abstract
The Echocardiography Quality Framework (EQF) is a unique, comprehensive, holistic approach to improving all aspects of an echocardiography service. The EQF is a patientcentered program, combining Quality Assurance and Continuous Service Improvement. The framework encompasses measures of (i) the quality of echocardiography, (ii) reproducibility and consistency, (iii) education and training, and (iv) customer feedback. The EQF is scalable and adaptable to benefit any echocardiography service. A catalogue or library of supporting documents is being developed by the British Society of Echocardiography (BSE), to be made available to any participating department. A mechanism and online infrastructure for (optional) national registration or assessment is being developed, to be used as a standalone adjunct or linked to BSE Departmental Accreditation. The principles that underpin the EQF may be applied to other imaging disciplines and, ultimately, other medical or surgical specialties.
Pragmatics of Crisis-Motivated Humour in Computer Mediated Platforms in Nigeria
Authors: Akinola Ayodele James 
Published: October 2018

Humour, an established means of releasing stress and tension has attracted scholarly attention over the years. In the Nigerian discourse context, studies on Crisis-Motivated Humour (CMH) via CMC platforms are scanty. This paper investigates humour shared through the social media which reflects the socioeconomic/political challenges in Nigeria in order to identify CMH as a form of humour through which real-life experiences of other people can be understood. Ethnography of Communication and Pragmatic act theory serve as the theoretical framework. Ten anonymous humorous compositions were randomly selected from WhatsApp and Facebook. CMH is a creative composition of jokes which reflects the Nigerians’ experiences, perceptions, imaginations and assumptions. They are purposefully composed by Nigerians, in order to downplay the effects of the crisis and bring temporary reliefs to the audience. These jokes elicit amusement, high-level wits and satirise the crisis situation(s). CMH are composed mainly in English with a blend of pidgin and a reflection of some Nigerianism. They are replete with verifiable, but exaggerated facts deployed through varying practs. Use of the first person singular pronoun ‘I’ and second person singular/plural ‘you’ with the use of simple present tense of verb among other grammatical elements, are a norm. All these make some of the jokes believable and also establish CMH as a unique genre of humour with an unlimited audience. CMH are often preserve-able and re-usable and thus serve as a relevant medium through which political leaders can assess the plights of the populace and access first-hand information on the ‘real’ impacts of the crisis.
A Monte Carlo Simulation Study Robustness of MANOVA Test Statistics in Bernoulli Distribution
Authors: Şahin Mustafa , Koç Şeyma 
Published: October 2018

The aim
of this study is to compare the robustness of Manova test statistics against
Type I error rate using the Monte Carlo simulation technique. In the method,
numbers are generated according to constant and increasing variance for g=3,4,5 group p=3,5,7 dependent variables n=10,30,60
sample size using the R. Numbers have been produced using these 54
combinations. Pillai Trace test statistic has been the least deviating from the
nominal α =0.05
value. Wilk Lambda and Hotelling-Lawley Trace test results were close to each
other. The researchers can decide according to the comparison results of the
analysis's suggested decision stage.
Reference Class Forecasting Method in Predicting Construction Project Duration
Authors: Bayram Savaş , Al-jıbourı Saad 
Published: October 2018

Project
delay is a global problem affecting construction and other industries in many
countries. Its impact on planning and budgeting can be serious for all
stakeholders involved and difficult to resolve. The purpose of this study is to
analyze the reliability of duration estimates of public building projects based
on actual duration of similar projects carried out in the past.Turkey is used
as a case study for this purpose and data from 643 public building projects
completed in Turkey were collected. The data include contract durations, actual
durations as well as the total construction areas for all projects. Reference
Class Forecasting (RCF) method is proposed and used to investigate whether it
would be possible to produce reliable and realistic project duration forecasts
based on such data. RCF can realistically predict the actual final duration of
the projects of different reference classes for various levels of acceptable
risks. Original estimates of the contract durations in Turkey are generally
optimistic or underestimated. Government buildings with the highest average
construction area required lower uplift values on the estimated durations to
produce accurate and realistic forecasts.So far the RCF method has been broadly
applied to predict project cost rather than duration. This paper describes it
use for forecasting duration in building projects.
Diabetes mellitus tipo 2 podría predecir una pérdida subóptima de peso después de una cirugía bariátrica
Authors: Núñez-Núñez Mizael A. , León-Verdín M. Guadalupe , Muñoz-Montes Norberto , Rodríguez-García Judith , Trujillo-Ortiz J. Abraham , Martínez-Cordero Claudia 
Published: October 2018

Introducción: la cirugía bariátrica no beneficia a todos los pacientes. Identificar a los pacientes gravemente obesos que tendrán éxito después de la cirugía bariátrica sigue siendo un reto para el equipo transdiciplinario. El objetivo de este estudio retrospectivo fue analizar factores dietéticos preoperatorios que pudieran predecir una pérdida de peso exitosa después de la cirugía bariátrica.Métodos: el estudio retrospectivo incluyó a pacientes sometidos a una cirugía de bypass gástrico laparoscópico en Y de Roux como procedimiento para obesidad severa (n = 84). Datos demográficos del paciente, comorbilidades, factores dietéticos y los resultados de pérdida de peso se extrajeron de la historia clínica electrónica.Resultados: la diabetes mellitus tipo 2 (DM2) se asoció con una pérdida subóptima de peso después de una cirugía de bypass gástrico laparoscópicoen Y de Roux.Conclusiones: aunque la cirugía bariátrica sigue siendo el tratamiento más efectivo para los pacientes con obesidad severa, es fundamental desarrollar estrategias para mejorar y mantener la pérdida de peso, especialmente en pacientes con DM2. Evaluar las características dietéticas de los candidatos a cirugía bariátrica es crucial.
Nanoparticles as Foam Stabilizer for Steam-Foam Process
Authors: Khajehpour Maryam , Reza Etminan S.. , Goldman Jon , Wassmuth Fred , Bryant Steven 
Published: October 2018

Summary
Steam foams have been considered effective additives for unconventional oil-recovery processes. Conventionally, for steam-foam applications, chemical additives are injected with steam. However, this procedure can have serious challenges because of poor thermal stability of additives and high volume of additives loss caused by adsorption to the rock surface. To overcome these limitations, nanoparticles can be used as novel additives to improve generation and stabilization of the foams for steam-foam applications.
In this study, silica nanoparticles in synergy with surfactants have been used as steam additives. Dynamic light scattering (DLS), a foam-height test using N2 at reservoir conditions, and thermal-stability analysis were designed to measure nanoparticle size distribution in brine, foamability, and thermal stability of the additive solutions, respectively. Subsequently, coreflooding tests were performed to evaluate the synergistic effect of nanoparticles and surfactants on the foam performance and oil recovery. We observed an optimal ratio of nanoparticle and surfactant that yields the best foam-generation performance in bulk medium. Herein, surface-treated silica nanoparticles have been tested with two of our candidate surfactants. The nanoparticles alone generate a small amount of foam, whereas each surfactant generates a small-to-moderate amount of foam. Synergy is demonstrated by the system that contains 0.1-wt% nanoparticles (the optimal concentration) and 0.5-wt% surfactant solution at neutral pH (≈7), as it leads to approximately 67 and 50% greater foam height, respectively, for Surfactants A and B than foam height observed in tests with surfactants only, in bulk medium. Corefloods with coinjected steam and water containing nanoparticles and surfactant confirm the synergy, exhibiting measurable improvement in mobility-reduction factor (MRF) and steam control, compared with coinjection of steam and water containing only surfactant.
A Semianalytical Model for Pressure-Transient Analysis of Fractured Wells in Unconventional Plays With Arbitrarily Distributed Discrete Fractures
Authors: Chen Zhiming , Liao Xinwei , Sepehrnoori Kamy , Yu Wei 
Published: October 2018

Summary
In this paper, we present an efficient semianalytical model for pressure-transient analysis in fractured wells by considering arbitrarily distributed fracture networks. The semianalytical model included three domains: matrix, hydraulic-fracture networks, and discrete natural fractures. Using the line-source function, we developed the diffusivity equation for fluid flow in matrix. By applying the vertex-analysis technique, we eliminated the flow interplay at fracture intersections and established the diffusivity equations for fluid flow in hydraulic-fracture networks and isolated natural fractures. The pressure-transient solution of these diffusivity equations was obtained using Laplace transforms and the Stehfest numerical inversion.
Results showed that with the discrete natural fractures, a “V-shaped” pressure derivative (the classical dual-porosity feature of naturally fractured reservoirs) emerged. With the hydraulic-fracture networks, the reservoir system would exhibit pressure behaviors such as “pseudoboundary-dominated flow,” “fracture-interference flow,” and “fluid-feed flow.” All these pressure characteristics were dependent on the properties and geometries of natural/hydraulic fractures. In addition, through synthetic field application, we found that different (natural/hydraulic) fracture distributions and geometries had distinct behaviors of pressure derivatives, which may provide an effective tool to identify the properties of randomly distributed natural fractures as well as complex hydraulic fractures in unconventional plays.
Centrifugal Pump Head Prediction using Affinity Laws Modified for Viscosity
Authors: Patil Abhay , Morrison Gerald , Delgado Adolfo , Casillas Hector 
Published: October 2018

Abstract
A new approach based on the similitude principle is used to evaluate the effect of fluid viscosity on pump performance. A well validated CFD technique of the entire stage of a mixed flow pump including the secondary flow path is utilized to develop this method. Simulations are carried out at different fluid viscosities representing the pump performance in laminar as well as turbulent flow regimes. The non-dimensional parameters such as head coefficient (Ψ), flow coefficient (ϕ) and rotational Reynolds number (Re) are utilized to characterize the pump performance. The head coefficient data for all viscosities collapsed to two separate lines when represented as a function of Φ∗Rew−a with each representing the separate flow regime for pump flow. The exponent "a" (called the Morrison number) is characterized as a function of the rotational Reynolds number and the specific speed of the pump. This procedure has the potential to completely characterize the performance of any pump with any specific speed at any operational speed, however, a larger data base is required to completely populate the Morrison number plot.
Efficacy of Surfactants in Rich Gas Shale Wells
Authors: Alzhanov Yermek , Karami Hamidreza , Pereyra Eduardo , Gamboa Jose 
Published: October 2018

Abstract
Foam lift has proven to be an effective method to mitigate liquid loading in unconventional resource (UCR) wells. Water-soluble surfactants are commonly used when liquid loading is mainly caused by formation water. There is a larger uncertainty involving the efficacy of water-soluble surfactant at water cuts below 80%. Therefore, oil-soluble surfactants are recommended. However, high oil-soluble surfactant price causes a significant increment in Opex, which can make the well production uneconomical.
Flow loop tests have been carried out in a closed-loop 2″ ID facility to emulate continuous backside foam injection. The oil condensate is emulated using a low density commercial isoparaffin oil, while tap water and compressed air are used instead of formation water and natural gas. The experiments are conducted at water cut values that range between 70% and 100% for surfactant concentration of 250 ppm. The foamer surfactant is a commercial water-soluble surfactant that is commonly used in oil field applications. The liquid loading onset is primary parameter obtained from each test through video and data analysis. Other parameters such as flow pattern and pressure gradient are also reported.
The experimental results show that liquid loading initiates at gas flow rates around 252 MSCFD for air-water flow in a 2-in. ID tubing. Adding the condensate fraction with a fixed total liquid rate and no surfactant slightly increases the critical gas rate. After surfactant injection, the reduction in critical gas flow rate is approximately 40% for most water cuts except the case of 70% water cut, where the oil presence seems to inhibit the surfactant effectiveness. Visual observations at this case show a significant reduction in generated foam, and relatively similar flow pattern transitions as the case of no surfactant. These results demonstrate that water-soluble surfactants are very effective in mitigating liquid loading at high water cuts, but their effectiveness reduces as water cut decreases. This causes an increase in the critical gas flow rate despite foam injection.
Currently, most operators aim to produce from condensate-rich shale in order to increase profit. The results of this study offer a first look in the following two issues. First, the effect of oil in liquid loading is investigated and the effectiveness of surfactant at different water cuts is evaluated. Second, the results can be used to design cost effective treatments based on water-soluble surfactants. Most literature about the effect of water cut on surfactant injection effectiveness is based on small scale lab. This experimental study is one of the few flow loop tests to investigate the effect of oil on the onset of liquid loading with surfactant.
End of Tubing and Packer Placement Effects on Gas Lift Operations in Toe Down Gas Wells
Authors: Nair J.. , Pereyra E.. , Sarica C.. 
Published: October 2018

Abstract
Gas lift operations in toe-down gas wells are usually dictated by convenience or knowledge based on previous experience. Parameters such as end of tubing location and packer placement are vital in determining efficacy of gas lift operations, alongside injection rate and injection location. The aim of this study is to quantify the effects of these parameters. The scope of this study is to provide guidelines to help assist design of gas lift systems for toe down gas wells.
A large scale experimental facility was constructed to study gas lift operations in toe-down gas wells. Air and water were used as test fluids, and the flow rates studied were those typically seen in toe down gas wells, resulting in slug flow being the dominant flow regime. Three end of tubing locations were studied, and in two of these locations the effect of a packer was quantified. Two different injection locations were studied as part of this study. Flow parameters such as pressure drop, holdup and slug characteristics were measured along the test facility.
Experimental results indicated that gas lift operations do not significantly affect the behavior of flow parameters such as holdup and pressure, upstream of the point of injection. The most significant effect of gas lift is observed to be a reduction of pressure drop fluctuations downstream of the point of injection. Packer placement also significantly affects gas lift performance, and it was observed that packered configurations are more efficient. Also, for a given end of tubing location, gas lift injection at the deepest point is observed to be the most effective in reducing pressure drop fluctuations.
This is the first experimental study conducted on the effect of end of tubing location and packer placement on gas lift operations on a large-scale test facility with field scale diameters for casing and tubing. Packer placement is currently dictated by mechanical concerns and depth limitations. This study addresses potential risks and benefits of running a packer as deep as possible, from a hydrodynamic standpoint.
Integrated Well Interference Modeling Reveals Optimized Well Completion and Spacing in the Marcellus Shale
Authors: Pankaj Piyush , Shukla Priyavrat , Kavousi Payam , Carr Timothy 
Published: October 2018

Abstract
Naturally fractured reservoirs such as the Marcellus shale require an integrated reservoir modeling approach to determine well spacing and well-to-well interference. The Marcellus Shale Energy and Environment Laboratory (MSEEL) is a joint project between universities, companies, and government to develop and test new completion technologies and acquire a robust understanding of the Marcellus shale. The study presented in this paper aims to reveal an approach to determine reservoir depletion with time through coupled geological modeling and geomechanical evaluation followed by completion and well performance history matching for a multiwell pad in the Marcellus shale.
The geomechanical model was prepared with interpreted vertical log data. A discrete natural fracture (DFN) model was created and used to determine the complexity of hydraulic fracture geometry simulated through complex fracture models on a two well pad. The microseismic data obtained during the hydraulic fracture simulations served as a constraining parameter for the hydraulic fracture footprint in these wells. Sensitivity to the DFN is realized by parametric variations of DFN properties to achieve a calibrated fracture geometry. Reservoir simulation and history matching the well production data confirmed the subsurface production response to the hydraulic fractures. Well spacing sensitivity was done to reveal the optimum distance that the wells need to be spaced to maximize recovery and number of wells per section.
Hydraulic fracture geometry was found to be a result of the calibration parameters, such as horizontal stress anisotropy, fracturing fluid leakoff, and the DFN. The availability of microseismic data and production history matching through integrated numerical simulation are therefore critical elements to bring unique representation of the subsurface reaction to the injected fracturing fluid. This approach can therefore be consistently applied to evaluate well spacing and interference in time for the subsequent wells completed in the Marcellus. With the current completion design and pumping treatments, the optimal well spacing of 990 ft was determined between the wells in this study. However, wells to be completed in the future needs to be modeled due to the heterogeneity in the reservoir properties to ensure that wells are not either underspaced to cause well production interference or overspaced to create upswept hydrocarbon reserves in the formation.
By adopting the key learnings and approach followed in this paper, operators can maximize subsurface understanding and will be able to place their wellbore in a nongeometric pattern based on reservoir heterogeneity to optimize well spacing and improve recovery.