bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Experimental Evaluation of Thermochemical Fracturing in Layered Formations
Authors: Tariq Zeeshan , Mahmoud Mohamed , Abdulraheem Abdulazeez , Al-Shehri Dhafer , Al-Nakhli Ayman , Asad Abdul 
Published: February 2020

Abstract
Current global energy demand and supply gap needs the best engineering methods to recover hydrocarbons from the unconventional hydrocarbon resources. Unconventional resources mostly found in highly stressed, over pressured, and deep formations, where the rock strength and integrity both are very high. The pressure at which the rock fractures or simply the breakdown pressure is directly correlated with the rock tensile strength and the stresses acting on them from the surrounding formations. When fracturing these kinds of rocks, the hydraulic fracturing operation becomes much more challenging and difficult, and in some scenarios reached to the maximum pumping capacity limits. This reduces the operational gap to optimally placed hydraulic fractures.
In the present research study, a novel thermochemical fracturing approach is presented to reduce the breakdown pressure of the high-strength layered formations. The new approach not only reduces the breakdown pressure of the layered rocks but also generate highly conductive fractures which can penetrate in most of the layers being subjected to fracturing. The hydraulic fracturing experiments presented in this study are carried out on four layered cement block samples. The composition of cement blocks is synthesized in this way that it simulates the real rocks.
The results showed that the newly proposed thermochemical fracturing approach reduced the breakdown pressure in layered rocks from 1495 psia (reference breakdown pressure recorded from conventional hydraulic fracturing technique) to 1107 psia. The post treatment experimental analysis showed that the thermochemical fracturing approach resulted in deep and long fractures, passing through majority of the layers while conventional hydraulic fracturing resulted in a thin fracture affected only the top layer. Thermochemical fluids injection caused the creation of microfractures, improved the porosity and permeability, and reduces the Young's modulus of the rocks. The new technique is cost effective, non-toxic, and sustainable in terms of no environmental hazards.
Uplifting the Profitability of a Mature Gas Giant in Pakistan Using Diminutive Sidetracks
Authors: Bugti Jahanzeb Ali , Ahmed Sheraz 
Published: February 2020

Abstract
One of the key challenges for Oil and Gas industry in current (low price) scenario, is efficient handling of mature Assets. This is because of the fact that reasonable amount of hydrocarbons still exist in such reservoirs but in scattered and partially-drained locations. Moreover, lower production rates, combined with ever-increasing costs, hardly satisfies the economic screening criteria for their expansion with new wells. This study presents an approach used on such a Mature Gas Giant in Pakistan, in order to re-vitalize old wells and exploit the scattered sweet spots (still prevailing in reservoir), with the help of a robust engineering and geological strategy.
The field under study was discovered in 1950s, in the eastern onshore area of Pakistan. The primary reservoir, under study, is a depletion drive fractured limestone i.e. no pressure support was observed in P/Z data. At present, more than 92% of the EUR has already been produced from this reservoir, which translates to 82% of Field In-Place volume. However, the performances of multiple wells have gone down with time, due to the depletion in Reservoir Pressure and the channeling of water towards producing wells-through the faulted/fractured zone. To cut water production and arrest the Annual field decline of 7-8 %, various activities have been carried out, including cementing, tubing size reductions, chemicals; but all the efforts went in vain.
In this paper, a detailed approach is presented, that was taken to tap the undrained areas in the vicinity of the existing producers - suffering from water hold ups and low gas rate problems. The Production logs were used first to identify the water production zone. Afterwards, a comprehensive algorithm was developed to analyze the Geological and Geophysical parameters and identify the undrained prospects while keeping minimal capital exposure. So far, a gain of around 10 MMScfd have been observed with the help of two engineered Sidetracks - which has added around 10 - 15 BCF reserves in our portfolio.
The most common issues encountered in a mature asset are liquid loading and water breakthrough. This study illustrates the methodology to resolve such issues with minimum investment towards the end of field life. It focuses on the benefits of sidetracks as a production enhancement tool, to reduce the annual decline. This paper offers an innovative approach, to utilize each geological and engineering data set in a systematic manner, in order to re-work old wells at optimum locations to evade issues affiliated with gas entrapment and water production. In the end, the paper also describes the evaluation process of production gains, geology, well construction, and completion types, that can be adapted to reap maximum rewards in such mature fields.
Experimental Investigation of Newly Synthesized Gemini Surfactants as Shale Inhibitors in Drilling Fluids
Authors: Murtaza Mobeen , Kamal Muhammad Shahzad , Hussain Syed Muhammad , Mahmoud Mohamed 
Published: February 2020

Abstract
Environmental concerns and the economic aspects curtail usage of oil-based drilling fluids (OBDF) during the drilling operations through shale formations. The OBDF is highly effective in controlling the swelling potential of the clay-rich shale formations in oil/gas wells. Hydration of shale formation by water-based drilling fluids (WBDF) leads to several problems such as collapse of boreholes, tight holes and stuck pipe which may preclude further drilling and time loss in rectifying the problems, leading to heavy economic losses. Designing the drilling fluid that reduces the interaction with shale, is important for safe and efficient drilling. This study investigates the new gemini surfactants as shale swelling inhibitors in the field of drilling.
To assess the performance of new cationic Gemini surfactants two reliable clay sources were considered. The first clay (Kaolinite) is from an unconventional formation and the second is sodium bentonite. The inhibition characteristics of gemini surfactants were tested using a dynamic swelling tester.
Different formulations based on commercially available solutions for shale swelling inhibitors were applied and compared with cationic shale inhibitor. It was observed that the new gemini surfactants reduced the shale swelling by different percentages for various gemini surfactants based on their spacer length. It also showed acceptable performance compare with common shale inhibitors used in the industry.
Employing Innovative Distributed Temperature Sensing Technique for Conclusive Downhole Leak Detection via Coiled Tubing: A Case Study from Pakistan
Authors: Khalid Aizaz , Briones Victor , Ramondenc Pierre , Mhiri Adnene , Khan Rao Shafin , Molero Nestor , Kamran Muhammad , Ali Syed Dost , Rashid Kamran , Mallah Sohail Ahmed 
Published: February 2020

Abstract
Leak identification across well completions is a crucial operation in the oil and gas industry. A failure of well barriers can result in uncontrolled release of hydrocarbons and pose major risks to personnel and environment. Downhole gauges are widely used to provide pinpoint measurements of pressure and temperature across the completion; however, those measurements alone are insufficient to properly diagnose single or multiple well integrity issues. Alternative well intervention methods are needed to qualitatively estimate the location and number of potential leaks.
For the past decade, distributed temperature sensing (DTS) has been used in wellbore completions and surface pipelines with preinstalled fiber optic lines to identify leaks by monitoring and processing temperature profiles across the length of the installation. The proposed methodology makes use of a similar principle, relying on coiled tubing (CT) to deploy the fiber optics and conduct DTS integrity assessment in wells completed without fiber optic lines. This use of fiber optics inside a CT pipe also provides simultaneous real-time downhole measurements, which include CT internal and annulus pressures, and casing collar locator (CCL), for precise depth control and accurate correlation of well parameters.
In the south of Pakistan, the tubing-casing annulus pressure of a high-temperature gas well increased to near flowing wellhead pressure at the tubing, giving a clear indication that at least one of the completion components had failed, resulting in flow of hydrocarbons to the annulus. Yet, the high wellbore temperature limited conveyance of conventional logging tools to assess downhole completion integrity. A thorough analysis of well hydraulics was first conducted to gather the possible options to identify the leak using DTS. This enabled the determination of a workflow aiming to create enough differential pressure to generate particular temperature disturbance. CT equipped with fiber optics was run and stationed across the complete wellbore length, and DTS data were acquired for approximately twelve hours under changing well conditions, including shut-in and flowing periods. The acquired temperature information for each phase, along with pressure information, helped to narrow down the location of possible leak points.
This methodology enabled the identification of a single, major leak point located at an expansion joint in the completion. The operator was able to riglessly set an annular plug to restore integrity, thus saving significant workover cost and time.
The Corrosion-Metallurgical Aspects of Sucker Rods and Their Oil Well Service Performance
Authors: Radd F.J. , McGlasson R.L. 
Published: February 2020

Published in Petroleum Transactions, AIME, Volume 201, 1954, pages 73–80.

Abstract
The mechanisms of corrosion and corrosion fatigue damages to sucker rods are examined from a fundamental electrochemical viewpoint, and the relationships of sucker rod microstructures to these damaging effects are defined. The common corrosive agents in crude oil production and storage are discussed as to types of attacks that they cause. The variations of fatigue strength with alloy content, surface preparation, and stress ranges are analyzed. Finally, conclusions are drawn as to how microstructures largely influence and control sucker rod performance.

Introduction
Greater than 90 per cent of the crude oil produced by artificial lift methods is produced through sucker rod pumping systems. In the USA each year more than $14 million is spent for sucker rods in new and old pumping installations. It is important to make this investment a wise one.
Essentially, the sucker rod system is a long series of steel rods, operating under alternating stress loadings and under mechanical vibrations, which connect the surface power source with the subsurface pump. These rods often operate in a variety of corrosive media, including water, brines, carbon dioxide, hydrogen sulfide, and air.
Basically, this paper is concerned with the problem of the behavior of certain steels in various corrosive media under high and dynamic stress patterns. The main objective of this paper is to show how, once, the stress effects and the corrosive environments are defined, one can still realize structural control and beneficial influence upon corrosion and corrosion fatigue.
Clinical Features and Survival of Pregnancy-Associated Breast Cancer: A Retrospective Study of 203 Cases in China
Authors: Han Bo-yue , Li Xiao-guang , Zhao Hai-yun , Hu Xin , Ling Hong 
Published: February 2020

Abstract
Purpose: Pregnancy-associated breast cancer (PABC) is an aggressive disease, and sinceChinese authoritybegan to encourage childbearing in 2015, the incidence of PABC has increased. This study investigated the characteristics and survival of PABC patients. Methods: Patients with PABC who underwent surgery at Fudan University, Shanghai Cancer Center between 2005 and 2018 were enrolled.Data concerning the tumor characteristics, maternal state (whether first or non-first pregnancy ) and survival outcome were recorded. Pearson Chi-square tests were used to compare the characteristics of the tumors, and Kaplan-Meier methods were used to perform the survival analysis. Results: Overall, 203 PABC patients were recruited. Since 2015, 65.5% of non-first pregnant women were diagnosed with breast cancer, it’s 5.7 fold of the incidence of PABC in non-first pregnant women. No significant differences in tumor characteristics were observed between the patients who were in their first pregnancy and those in non-first pregnancy. Among the entire PABC population, luminal B breast cancer accounted for the largest proportion (38.4%), followed by triple-negative breast cancer (TNBC, 30.0%). The distribution of the molecular subtypes of PABC and non-PABC differed (P<0.001) as follows: in the PABC patients, Luminal B 38.4%, Triple negative breast cancer (TNBC) 30.1%, Human Epidermal Growth Factor Receptor 2 (HER-2) overexpression 15.8%, and Luminal A 10.8%; in the non-PABC patients, Luminal A 50.9%, Luminal B 20.1%, TNBC 17.4%, and HER-2 overexpression 8.0%. The 3-year disease free survival (DFS) of all PABC patients was 80.3%. The 3-year DFS of the patients in the first-pregnancy group was 78.4%, and that of the patients in the non-first-pregnancy group was 83.7% (P=0.325). Conclusions: Our study proved that the proportion of women who developed PABC during the second or third pregnancy was extremely high relative to the newborn populations. The patients in the PABC population tended to present more luminal B and TNBC breast cancer than the non-PABC patients.
Why institutional delivery is still the last option to rural women in North West Ethiopia: Qualitative study
Authors: Babbel Netsanet Fentahun , Wasihun Yosef , Mekonnen Wubegzier , Alemayehu Mulunesh Alemayehu Mulunesh 
Published: February 2020

Abstract
Background: Whatever the actions has been implemented, home delivery preference in Ethiopia is still over 72%. To date, no studies explored why institutional delivery is still the last option to rural women in Ethiopia. This study was conducted to explore the reason why institutional delivery is still the last option to rural women in Awi Zone Northwest Ethiopia.
Methods : An explanatory qualitative study was conducted from February to March 2014. Participants were selected purposively and written informed consent was sought. Twelve reproductive aged females, ten religious and twelve community leaders and sixteen key informants were participated. Data were collected by using semi-structured questionnaire using focused group discussion and in-depth interview guides. Thick description and peer debriefing were applied to assure data quality. Thematic analysis framework was used to analyse the data.
Results : The study revealed that institutional delivery is still the last option to the study area. Individual related factors like information gap, low risk Perception to pregnancy and delivery have been mentioned as drive factors for not using institutional delivery. Community related factors of women’s poor position to decision, beliefs and cultural practices for home delivery preference affects institutional delivery. In addition, health facility related barriers like inaccessibility of health facility, infrastructure, lack of privacy during delivery, misconducts of health care providers and high risk perception to health facility delivery were repeated raised as reasons of last option of institutional delivery.
Conclusion: This study elucidated that home delivery preference was existed, given high social and cultural price for home delivery and misconceptions towards institutional delivery. Thus, the Ethiopian government together with its partners should focus on accessing health facilities, infrastructure, equipping health facilities with essential materials and skilled health professionals and increasing knowledge of the community, avert communities’ misconceptions and deep-rooted socio-cultural beliefs towards institutional delivery.
EphB4/ TNFR2/ERK/MAPK signaling pathway comprises a signaling axis to mediate the positive effect of TNF-α on osteogenic differentiation
Authors: Zhang Yu , Yang Chengzhe , Ge Shaohua , Wang Limei , Zhang Jin , Yang Pishan 
Published: February 2020

Abstract
Background : Low concentrations of tumor necrosis factor-alpha (TNF-α) and its receptor TNFR2 are both reported to promote osteogenic differentiation of osteoblast precursor cells. Moreover, low concentrations of TNF-α up-regulate the expression of EphB4. However, the molecular mechanisms underlying TNF-α-induced osteogenic differentiation and the roles of TNFR2 and EphB4 have not been fully elucidated. Results : This study showed that with increase in ALP activity, mRNA and protein expression of RUNX2, BSP and EphB4, TNFR2 expression was significantly promoted under 0.5 ng/ml TNF-α stimulation in osteoblast precursor cells MC3T3-E1. After TNFR2 was inhibited by gene knockdown with lentivirus-mediated shRNA interference or by a neutralizing antibody against TNFR2, the pro-osteogenic effect of TNF-α was partly reversed, but up-regulation of EphB4 by TNF-α kept unchanged. With EphB4 forward signaling suppressed by a potent inhibitor of EphB4 auto-phosphorylation, NVP-BHG712, TNF-α-enhanced expressions of TNFR2, BSP and Runx2 were significantly decreased. Further investigation into the signaling pathways revealed that TNF-α significantly augmented expression of p -JNK, p -ERK and p -p38, however, only p -ERK expression was significantly inhibited in TNFR2-knockdown cells. In addition, the ERK pathway inhibitor, U0126 (10μM), significantly inhibited the protein levels of RUNX2 and BSP when compared with cells treated with TNF-α only. Conclusions : The EphB4, TNFR2 and ERK/MAPK signaling pathway comprise a signaling axis to mediate the positive effect of TNF-α on osteogenic differentiation.
Untreated dental caries prevalence and impact on the quality of life among 11 to14-year-old Egyptian schoolchildren: A cross-sectional study
Authors: Eid Samar , Khattab Nagwa , Elheeny Ahmad 
Published: February 2020

Abstract
Background
This study aimed to assess caries prevalence and experience among 11-14 years, school children, analyze demographic, socioeconomic, personal and professional dental care in relation to untreated carious lesions, and evaluates the effect of decayed teeth on early adolescents’ oral health-related quality of life (OHRQoL) .
Methods
A cross-sectional analytical investigation conducted on 1020 preparatory schoolchildren selected on the basis of a multistage sampling technique. Caries status of the participants detected via recording their caries experience and untreated cavities using DMFT and DT indices. OHRQoL was determined using a validated Arabic CPQ11-14 short-form questionnaire. Statistical methods for descriptive analysis, chi-square test, Independent-Samples T-Test and one-way analysis of variance (ANOVA) were used . Multi variate level Poisson regression analysis through a hierarchical approach was used to detect the influence of independent variables on DT scores. To declare the association between independent variables and QoL , a step-by-step, multivariate regression analysis was conducted .
Results
The average scores of DMFT and DT in this study were 2.97±1.29 and 1.66±1.24. Poisson regression analysis demonstrated that early adolescents whom their mothers with a lower level of education and of low socioeconomic status were 1.41 and 1.27 times respectively had higher DT scores when compared with their peers. Untreated cavities affected mainly by mother education, school type, family income, and regular dental appointments. Children with DMFT ≤ 3) or DT =0 recorded a statistically significant lower CPQ11-14 average score ( p ˂ 0.01) and ( p ˂ 0.0001) respectively.
Conclusions
Untreated carious cavities and caries experience were associated with lower socioeconomic, maternal education And less frequent tooth brushing. Untreated carious cavities have a significant negative impact on schoolchildren’s QoL .
Detection of Cercopithifilaria bainae infection in shelter dogs and ticks in Oklahoma, USA
Authors: Lineberry Megan W. , Sundstrom Kellee D. , Little Susan E. , Stayton Erin M. , Allen Kelly E. 
Published: February 2020

Abstract
Background

Cercopithifilaria bainae is a filarioid nematode of dogs. Infection with the parasite was not reported in the USA until 2017, when a dog with skin lesions in Florida was diagnosed. Brown dog ticks, Rhipicephalus sanguineus sensu lato, are the purported tick vectors, and are widespread in the USA. Therefore, C. bainae is likely present in additional states. Here, we tested dogs and ticks in Oklahoma for evidence of C. bainae infection.

Methods

Dermal punch biopsies were opportunistically collected from municipal shelter and client-owned dogs. Multiple skin samples collected from interscapular and head regions were tested by saline sedimentation to recover live microfilariae for morphometric identification and by PCR to amplify a 330 bp region of the filarioid 12S rRNA gene. Also, ticks observed on surveyed dogs were collected, identified to species level, and tested for filarioid DNA.

Results

A total of 496 saline sedimentations were performed on 230 shelter and 20 client-owned dogs. Cercopithifilaria bainae infections were identified in 2.6% (6/230) of shelter dogs by morphometry of microfilariae in sedimentations and/or amplification of DNA from skin. DNA sequences amplified from PCR positive skin samples were 99–100% identical to C. bainae reported in Italy. All skin samples from client-owned dogs were negative for filarioid infection by saline sedimentation and PCR. A total of 112 ticks, comprised of four species, were collected. Two of 72 R. sanguineus s.l., both engorged females found attached to a C. bainae infected dog, harbored C. bainae DNA (99–100% identity). One attached R. sanguineus s.l. male on the same dog harbored filarioid DNA sequence which was difficult to interpret at numerous base-pair locations, but was closest in identity (~80%) to C. bainae .

Conclusions

The distribution of C. bainae is more widespread than previously known. Here, we document C. bainae infections in dogs and DNA in brown dog ticks in Oklahoma for the first time. As brown dog ticks are commonly found throughout the USA, veterinarians in this region should consider C. bainae infection as a differential diagnosis in canine patients with dermatitis or polyarthritis.