bluuebunny/crossref_metadata_2025 huggingface dataset:
Pre-Exposure to Dennettia tripetala Ethanolic Fruit Extract Prevents Biochemical Alterations in Rats Subsequently Exposed to a Single Dose of Carbon Tetrachloride
Authors: Iseghohi Sylvia O. , Orhue Noghayin E.J. , Omage Kingsley
Published: February 2017

Dennettia tripetala(DT) is consumed in West Africa as a spice. It is also used in traditional medicine for treating cough, fever and other ailments. Its fruits have been shown to possess phytochemicals with proven antioxidant capabilities. DT roots elicitin vitroantioxidant capabilities similar to that of ascorbic acid. In this study, we evaluated the potency of the ethanol extract of DT fruits in preventing liver damage induced by a single oral administration of Carbon tetrachloride (CCl4). Thirty female Wistar albino rats were randomized into six groups of five animals each: Group A served as control, Groups B-D were given increasing doses (250, 500 and 1000mg/kg b.w respectively) of DT extract for 14 days by gavage; on day 15, they were given CCl4(3ml/kg bw) by gavage. Group E was given the highest dose of DT for 14 days without CCl4while Group F was given only CCl4on day 15. Administration of CCl4resulted in liver and kidney injury detected as significant increases in plasma ALT, AST, ALP and GGT activities as well as plasma total protein, urea, creatinine, plasma and liver triglyceride and cholesterol as well as liver and kidney malondialdehyde concentrations. CCl4also caused a reduction in liver and kidney SOD and catalase activities as well as plasma albumin concentration. Pre-treatment withDennettiatripetalahowever, significantly prevented damage to the liver and kidney. Under the conditions of this study,Dennettia tripetalashows potential in preventing liver and kidney damage and has no noticeable side effects.
Flavonoids and Diarylheptanoids: Neuroprotective Activities of Phytochemicals
Authors: Parasram Kathyani
Published: February 2017

Plants are often used as sources of lead compounds with phenolic compounds frequently attributed to physiological effects. Flavonoids and diarylheptanoids are important groups of phenolic compounds that impart antioxidant, antitumorgenic, antinflammatory, and neuroprotective effects. These neuroprotective effects can be harnessed to develop treatments for neurodegenerative diseases, such as Alzheimer’s and Parkinson’s disease. Recent discoveries have characterized new neuroprotective compounds and/or sources and tested treatments on cell lines and model animals to improve treatments for future persons with neurodegenerative disorders.
Fostering Practice Self-Efficacy: An Exercise to Promote Student Self-Efficacy and Evidence-Based Practice
Authors: Ogden Lydia
Published: February 2017

This teaching note describes my experience discovering and addressing challenges to graduating baccalaureate social work students' self-efficacy, particularly on the use of a substance-use-oriented evidence-based practice (EBP) in fieldwork placements. This discovery led to the development of an exercise, presented here, to proactively identify and address such challenges. The exercise consists of a structured discussion that invokes theory and professional responsibility, followed by the instructor modeling role playing for the class. The exercise culminates in dyadic role playing between students with individualized feedback provided by the professor. In addition to promoting student self-efficacy, the exercise is designed to address practice competencies specified by the Council on Social Work Education's Educational Policy and Accreditation Standards and specifically to promote the use of EBP in the field.
Honoring Resilience Narratives: Protective Factors Among Indigenous Women Experiencing Intimate Partner Violence
Authors: Burnette Catherine , Hefflinger Timothy
Published: February 2017

Despite the need for education among undergraduate social work students and practitioners to provide culturally relevant services to address the disproportionate rates of violence against Indigenous women in the United States, little is known about which factors Indigenous women identify as protective. Thus, the purpose of this article is to uncover Indigenous women's narratives of resilience or emergent protective factors related to experiences of intimate partner violence (IPV). As part of a broader critical ethnography, results emerged from thematic analysis of ethnographic interviews with 29 Indigenous women who had experienced IPV. Women reported the following protective factors: (a) an educational orientation; (b) affirming talents and abilities; (c) constructive coping, which included helping others and expressing emotions; (d) faith; (e) optimism and resilience perspectives; and (f) self-reliance and inner strength. Identified protective factors may guide education for social work students and practitioners regarding how to engage in strengths-based practice with these populations.
Predatory Journals : Do Not Enter
Authors: Khan Faizan , Moher David
Published: February 2017

AbstractThe escalation in open-access publishing has fueled the rise of questionable businesses, namely, ‘predatory’ journals. Predatory journals and their publishers seek manuscripts through aggressive electronic solicitation and execute flawed peer-review practices, consequently undermining the scholarly record and current research cultures, globally. As these journals are not indexed in any legitimate databases, the research they publish is often undiscoverable and fails to be disseminated to a worldwide readership. Acknowledging this threat to the credibility of science, this article aims to alert researchers at various levels of their career of the increasing global issue of predatory journals, and offer helpful advice and resources for identifying and avoiding them. RésuméL’essor de la publication en accès libre a alimenté l’expansion d’entreprises douteuses, à savoir des revues « prédatrices ». Les revues prédatrices et leurs éditeurs recherchent des manuscrits au moyen de requêtes électroniques agressives et effectuent des évaluations erronées par les pairs, compromettant ainsi les archives scientifiques et les présentes cultures de recherche dans l’ensemble. Puisque ces revues ne sont pas répertoriées dans des bases de données légitimes, la recherche qu’elles publient est souvent introuvable et ne parvient pas à être diffusée à un lectorat mondial. En reconnaissant cette menace à la crédibilité scientifique, cet article vise à alerter les chercheurs à diverses étapes de leur carrière du problème global croissant que constituent les revues prédatrices, et à leur offrir des conseils utiles et des ressources permettant de les identifier et de les éviter.
Do we need to screen and treat pregnant women for subclinical hypothyroidism? A cross sectional study in a rural tertiary centre in Kerala, India
Authors: K. R. Radha , Sugunan Nishu , C. R. Resmy
Published: February 2017

Background: Hypothyroidism (HT) is associated with maternal and perinatal morbidity. Subclinical HT rather than overt occur in pregnancy, because overt HT causes infertility. Treatment of overt HT was beneficial in reducing the fetal and maternal complications, Usefulness of correcting subclinical hypothyroidism was doubtful, hence Universal screening of pregnant women was not recommended.Methods: Cross sectional study, conducted in the department of obstetrics and gynecology, Government Medical College, Thrissur, Kerala, India. 50 consecutive cases of subclinical hypothyroidism in pregnancy were analyzed for Thyroid function, antenatal, natal, postnatal complications. Perinatal complications, including neonatal hypothyroidism also noted. Statistical analysis done using computer software Epi info3.4. Data expressed in its frequency and percentage, continuous data in mean.Results: All women in the study group received levothyroxine during pregnancy from time of diagnosis. At the time of delivery 84% women were euthyroid and 16% hypothyroid. Complications like anemia 36%, abruption 4%, and postpartum hemorrhage 6% showed a statistically significant association, while pre-eclampsia 20%, preterm labor 22% had no statistically significant association. Comparing the women who are euthyroid as a result of levothyroxine supplementation to women inadequately treated, complications like anemia (33% versus 50%, p value 0.042), abruption (0% versus 4%, p value0.023), PPH (2% versus 6%, p value 0.014) were significantly less in well controlled.Conclusions: Significant association was noted between inadequately treated hypothyroidism and maternal complications like anaemia, placental abruption, placenta previa, PPH, preterm delivery, and caesarean section rate for foetal distress. Universal screening of pregnant women for thyroid status is recommended.
Epidemiology of patients with bad cervix attending gynaecology OPD of a tertiary care centre in Western Uttar Pradesh, India
Authors: Bhatnagar Kriti , Baghel Kalpana
Published: February 2017

Background: Cervical cancer is one of the biggest health problems of women around the world. An estimated 4,70,000 new cases are diagnosed worldwide annually with about 80% of these being in developing countries with India contributing to about a quarter of it. Pap smear and colposcopy are two non-invasive methods for screening of cervical cancer with varying sensitivity and specificity. This study uses these along with histopathology to find out premalignant lesions in women of rural western Uttar Pradesh, India and to find their correlation with various socio-demographic features.Methods: This prospective clinical study was carried out in department of Obstetrics and Gynaecology in Muzaffarnagar Medical College from 1st January 2012 to 31st December 2014. Those patients who fulfilled the inclusion criteria had their Pap smear done at first visit followed by colposcopy when cytology report was available. Colposcopically indicated biopsy was done only in those patients who had suspicious areas on colposcopy.Results: Out of total 500 women included in the study majority although having a bad cervix were having a normal pap smear (45%). LSIL and HSIL were present in 17.4% and 9.8% respectively. Squamous metaplasia was the most common abnormal finding seen in 12.2% of cases followed by acetowhite areas (7.6%). Only 137 patients who had abnormal colposcopic findings were subjected to biopsy.Conclusions: In present study it was found that increasing age, early age at coitarche and high parity are risk factors for high grade lesions. Colposcopy served as a tool to decrease the need for invasive procedure i.e biopsy.
Comparative analysis of non-descent vaginal hysterectomy versus total abdominal hysterectomy in benign uterine disorders
Authors: Abrol Shivani , Rashid Shazia , Jabeen Farhat , Kaul Shiveta
Published: February 2017

Background: Hysterectomy is the most common operation performed by gynecologist, next to caesarean section. Currently, there are three main types of hysterectomy operations in practice for benign diseases-Abdominal hysterectomy (AH), vaginal hysterectomy (VH) and Laparoscopic hysterectomy (LH). Vaginal route for non-descent uterus is an acceptable method of hysterectomy. The objective of present study was to compare the operating time, intraoperative and postoperative complications between VH and TAH in non-descent uterus.Methods: The study was conducted in the Postgraduate department of Gynaecology and Obstetrics for a period of 18 months between April 2013 to October 2014 in the Government Lalla Ded Hospital - an associated hospital of Government Medical College, Srinagar; which is the sole tertiary care referral centre in the valley.Results: Over the study period 100 patients were taken, 50 patients underwent non-descent vaginal hysterectomy and labelled as group A and 50 patients were under went total abdominal hysterectomy and labelled as group B. It was seen that intraoperative complications and postoperative complications were less in group A patients and operating time is also less with group A patients when compared with group B patients.Conclusions: From the present study, it was concluded that NDVH is associated with less blood loss during surgery, quicker recovery, and early mobilization, less operative and less postoperative morbidity when compared to TAH. NDVH is a less invasive technique with shorter hospital stay and faster convalescence.
Evaluation of perinatal outcome in women presented with first trimester vaginal bleeding: our experience
Authors: Rai Priyanka , Kumari Girija , Kumari Kalpana , Jaiswal Deepshikha
Published: February 2017

Background: First trimester vaginal bleeding (FTVB) plays a role in occurrence of late pregnancy complications in both mother and infant. Late pregnancy outcomes in mothers and infants are the main concerns for the obstetricians. The purpose of this study was to assess the perinatal outcome of pregnancies complicated by first trimester vaginal bleeding.Methods: The present study included total 100 singleton pregnant women with history of FTVB whose pregnancy was confirmed chemically. Patients were closely observed and follow up done 2 weekly upto 36 weeks and weekly after that. Late pregnancy outcomes such as gestational hypertension, pre eclampsia, placental abruption, preterm delivery and pre mature rupture of membranes in the mothers and  low birth weight, intrauterine growth ristriction, apgar score after 1 and 5 minutes,  and  NICU admission in new born were calculated.Results: Incidence of PROM, gestational hypertension and placental abruption is more in women with FTVB. However there infant had higher rate of IUGR and LBW. Apgar score after 1 and 5 minutes were less than 5 and admission to NICU too.Conclusions: FTVB is an important factor to predict both the maternal and fetal outcomes in late pregnancy. It is therefore important to evaluate and consider these pregnancies as high risk group and provide careful antenatal care.
Привлечение бизнеса к участию в государственном управлении: опыт и проблемы
Authors: Борщевский Георгий Александрович
Published: February 2017

В статье обосновано утверждение, что в современном мире социальные процессы значительно осложняются наличием информационных технологий и новых средств коммуникаций. В связи с этим возникает необходимость в совершенствовании процессов взаимодействия государства и бизнеса.
Показано, что, реализуя принципы открытости, государственная власть упрощает себе задачу создания эффективного механизма взаимодействия с предпринимательским сообществом. Чем сложнее устроено общество, тем серьезнее требования, которым такой интерфейс должен удовлетворять. Вовлечение представителей экспертного сообщества и предпринимательства в поиск таких решений повышает степень их доверия государству и его представителям на всех уровнях власти.
Рассмотрены конкретные примеры привлечения представителей экспертов бизнеса к побуждению и принятию государственных решений: деятельность Общественной палаты РФ, общественных палат субъектов РФ, общественных советов при органах государственной власти. Дан критический обзор практики проведения общественного контроля, антикоррупционной экспертизы и оценки регулирующего воздействия проектов правовых актов. Рассмотрены проблемы и перспективы совершенствования политики открытости государственных органов власти.
Resultados de la evaluación de sostenibilidad de la estructura urbana del Área Metropolitana de Mendoza a la luz de una metodología específica
Authors: García Schilardi María Emilia
Published: February 2017

Desde la década de los noventa se desarrollan fuertes procesos de urbanización a escala mundial. Son las ciudades los ámbitos en donde las personas residen y (re)producen su vida cotidiana y en donde se generan los más fuertes impactos ambientales negativos.En este contexto, toma relevancia la consideración de características deseables de sostenibilidad urbana para la mejora de la vida cotidiana en las ciudades o sistemas urbanos del siglo xxi. Este trabajo tiene como objetivo evaluar la sostenibilidad de la estructura urbana del área metropolitana de Mendoza a través del marco metodológico propuesto por Camagni y Pozueta. Se adopta, entonces, una metodología de análisis de información a través de indicadores expresados en tablas y cartografía. Es decir, en este artículo se presentan los resultados de aplicar una metodología y unos indicadores a la realidad cuantitativa del área metropolitana de Mendoza. Como principal resultado se detecta que el área en estudio no alcanza los estándares mínimos de sostenibilidad y se proponen algunas medidas para revertir esa situación.
“EF” Method for Determination Books Inventory Number on Book Acquisition at Library Of Lampung University Case Study : Acquisition Book At 2012 And 2013
Authors: Fitriani Erni
Published: February 2017

Inventory is an activity of book registration or recording bibliographic data collection into the main book or book inventory in accordance with the type of collection. Before September 2012, the inventory of books, especially in determining books inventory number, have been done by manual counting, so it often goes wrong in the book inventory. In November 2012 at the Library of Lampung University, Acquisition Book Division received 1473 titles/7357 copies. In 2013, the Library have received 1684 titles/16.870 copies. The books that received from the publishers was composed in a box in random order. The aims of “EF” method are: 1) to determine books inventory number easier, more effective, and faster; 2) to minimize the error in determining books inventory number. The method used is descriptive quantitative which consists of making a description, an image or picture in a systematic and factual from the existing problems which is to determine the books inventory number: a case study in acquisition books in 2012 and 2013. The results and conclusion are “EF” method in determining the books inventory number in 2012 and 2013 is easier, more effective, and faster, and “EF’ method can minimize errors in determining the books inventory number.
Fulfillment Research Resources through Access Financial Report fo Go Public Company at Library STIE Perbanas Surabaya Perpustakaan STIE Perbanas Surabaya
Authors: Bestari Melati Purba
Published: February 2017

Modern libraries are characterized by the diversity of information services to users, including to fulfill the information needs of researchers. Fulfilling the information requirements for this research group is very important because the information provided affect the quality of research. Library of STIE Perbanas Surabaya efforts to fulfill the information needs of researchers is to provide research resources through the provision of access annual and financial report for go public company. To provide convenience to users who do research and need annual and financial report for go public, library of STIE Perbanas Surabaya provide easy access through online catalog. To fulfill the annual and financial report for go public company, library tracked data on Indonesian stock exchange and go public company. Library attempts to provide easy access to information is expected to support a process that requires researchers and annual and financial report data so as to improve the quality and quantity of scientific works in the field of economics science, especially for subject of banking, finance and business.
Informational Books for Children
Authors: Asri Tri Mega
Published: February 2017

The ignorance of reading activity is a result of condition in which people are not accustomed to read because they are not familiar with the culture of writing. It is fueled by the entry of telecommunications technologies and broadcasting, especially children digital native generation. The ability to speak and communicate in children is very influential in the development of social interaction. Besides the language and communication skills are directly related to the process of thinking and developments in the search for solutions to problems in children. Informational books is one medium that can help the development of language and communication skills in children. Informational books can convey knowledge of all the things they want to know the child, about science, about everything that exists and happens around the child to see the writing in a language that has a characteristic and image. The method used is literature study and data collection techniques to conduct a study review of the relevant literature. Informational books children as a means of communication, various forms of media including books have a major influence in shaping attitudes and behavior of children. A wide variety of informational books that has developed its own current trend where its use on children in need of assistance.
Medicinal Value of Curcuma cassia roxb: An Overview
Authors: Bhupendra Sahu  , Rameshroo Kenwat  , Shashikant Chandrakar
Published: February 2017

Curcuma caesia is commonly known as kali haldi and it belongs to the family Zingiberaceae.  Black turmeric is an uncommon endemic as well as ethno medicinally important of South East Asia. This herb is available throughout north-east, central India, Papi Hills of East Godavari, West Godavari, and Andhra Pradesh. In the traditional system of medicine, fresh and dried rhizomes of Curcuma caesia are used in treating leucoderma, asthma, tumours, piles, bronchitis, bruises etc. Curcuma caesia has scientifically studied for various therapeutical activities like antioxidant, antibacterial, antipyretic, larvicidal, insecticidal, antimicrobial, wound healing and anti-hyperglycaemic. The present review is an effort to give a detailed survey of the literature on its, phytochemistry, traditional uses and therapeutical studies.
Implementation method experiments on student results on substances being material and its amendment in class VII SMP Negeri 22
Authors: Trisianawati Eka , Nurhayati Nurhayati , Beniwati Lusi
Published: February 2017

The aims of this research were to know: (1) the average student learning outcomes in states of matter and changes the material that is taught by an experimental method in class VII SMP Negeri 22 Pontianak; (2) the average student laerning outcomes in states of matter and changes the material that is taught by  conventional method in class VII SMP Negeri 22 Pontianak; (3) the average difference in student learning outcomes given the experimental method to the average student learning outcomes given conventional methods in states of matter and changes the material in class VII SMP Negeri 22 Pontianak . This research was a quasi-experimental design with Nonequivalent Control Group Design. The study population was all students of class VII SMP Negeri 22 Pontianak which consists of five classes, namely class VII A, VII B, VII C, VII D and E VII academic year 2015/2016, with a sampling technique that cluster random sampling. Based on the results of class VII A by Not set" href="#43308853"> lottery was chosen as an experimental class and class VII D as the control class. The data collection technique used is the technique of measurement. Data collection tool used is a form of essay test. The hypothesis was tested using the t-test. Based on the results of data analysis can be concluded that: (1) the average student learning outcomes in states of matter and changes the material that is taught by an experimental method in class VII SMP Negeri 22 Pontianak is 64.96, (2) the average student learning outcomes in material states of matter and the changes that are taught by conventional methods in class VII SMP Negeri 22 Pontianak is 49.85, and (3) there are differences in the average student learning outcomes given the experimental method to the average student learning outcomes given in the conventional method material phase transition and changes in class VII SMP Negeri 22 Pontianak.
Peranan Sifat Fisikokimia Sorgum dalam Diversifikasi Pangan dan Industri serta Prospek Pengembangannya
Authors: Suarni Suarni
Published: February 2017

Pemanfaatan sorgum untuk pangan dan industri dari bahan setengah jadi (sorgum sosoh, tepung, dan pati) sebaiknya berlandaskan pada karakter sifat fisikokimia. Hasil penelitian menunjukkan bahwa setiap varietas sorgum memiliki sifat fisikokimia dan komponen bioaktif fungsional yang berbeda. Informasi ini dapat menjadi pertimbangan awal dalam memilih varietas sorgum sesuai dengan produk yang diinginkan. Berbagai inovasi teknologi produk pangan dan industri berbasis sorgum, termasuk gula cair dan bioetanol dari batang sorgum manis telah dihasilkan. Untuk mempromosikan sorgum sebagai bahan diversifikasi pangan dan industri yang prospektif, diperlukan dukungan riset, iptek, dan kebijakan. Tersedianya varietas unggul sorgum, yang didukung dengan inovasi teknologi pengolahan pangan dan industri yang memadai, menjadikan komoditas ini potensial untuk dikembangkan.
 
Does Unit-Slope Beyond Maximum Producing Time Always Represent BDF in RTA?
Authors: Hasan S. S. , Mattar L.
Published: February 2017

Production data is usually analyzed by plotting the normalized rate (q/Δp) Vs. Material Balance Time (MBT) on a log-log scale. A late-time unit-slope is usually interpreted as boundary-dominated flow (BDF) and can be used to calculate the reservoir volume. However, a decreasing flow rate not only causes MBT to be larger than Maximum Producing Time (MPT), in certain cases it can also create an artifact of false unit-slope giving the wrong impression of achieving BDF. There are claims in the literature (Agnia et al., 2012) that all data beyond MPT should be ignored.

This paper presents a detailed analysis of the issue, and investigates the conditions under which data beyond the MPT should be ignored. Three different reservoir models have been used with associated pertinent flow regimes to cover and demonstrate the subject. Specifically, it addresses questions such as: What causes MBT to be larger than MPT?; Under what conditions can that data be meaningful? and Should MBT data that extend past the MPT must always be ignored?

The question whether MBT is valid beyond MPT and under what conditions, has been investigated in great detail in this paper. The observations are that: If flow is transient, then any data beyond MPT should be ignored (except for a constant flowing pressure).If flow is boundary-dominated, data beyond MPT is valid and it accentuates the correct interpretation.To differentiate between transient and boundary-dominated flow, use of external information is often necessary.Bad data will often manifest themselves beyond MPT and should probably be ignored.

It has been shown that even when flow is transient, a unit-slope may be observed on the q/Δp Vs. MBT plot. This is a false trend and will give the wrong HCIIP. When the flow is Transient, the volume of investigation is still increasing with time, and any volume corresponds to a "minimum." Observations during this study indicate that the "calculated volume" based on the apparent (false) unit-slope data is approximately one-half of the "correct reservoir volume." However, when flow is boundary-dominated, the observed unit-slope on the q/Δp Vs. MBT plot is a true trend and will give the correct HCIIP.
Waterflooding a Multi-layered Tight Oil Reservoir Developed with Hydraulically Fractured Horizontal Wells
Authors: Hustak Crystal , Dieva Rous , Baker Richard , MacIsaac Ben , Frankiw Ken , Clark Bryan
Published: February 2017

A successful waterflood can be implemented in a multi-layered tight oil reservoir developed with horizontal multi-fractured wells. This paper forecasts the recovery factor that can be achieved in such a reservoir as well as discusses the challenges of analyzing and modelling tight oil reservoirs developed with multi-fractured horizontal wells.

With some unconventional reservoirs that are hydraulically fractured, a phenomenon exists whereby material balance and simulation indicate pressure support from a water source that is not always obvious. This phenomenon is believed to be related to the multi-layered silts/shales in the reservoir and is not typically seen in simulation of conventional higher permeability reservoirs (Kair >10 mD). Although, the exact petrophysical nature of the silts/shale reservoir layers in this project are not well defined at this time, a successful production history match can be achived by incorporating their input into a simulation model.
Localized Reservoir Characterization Model for Hydraulic Fracturing Design in Tight Reservoirs
Authors: Olusola Bukola , Boury Nahla , Aguilera Roberto
Published: February 2017

Tight reservoirs with low and ultralow permeability must be successfully stimulated to produce at economic oil or gas rates. For this reason, costs of drilling and completing wells are very high in tight reservoirs. In order to reduce these costs, operators have often tried to replicate the same or similar hydraulic fracturing designs that have been successfully used in previous wells in the same geological area. This strategy sometimes results in unexpected surprises and operational challenges leading to unsuccessful stimulations and poor production performance. The major reason behind these challenges is that tight reservoirs exhibit a localized behavior with changes in reservoir quality such as mineralogy, hydrocarbon content, and thickness across the same reservoir.

In order to study the localized behavior of tight reservoirs; three wells that penetrated the Eaglebine formation in Texas were evaluated. The Eaglebine formation contains both the Eagle Ford and the Woodbine reservoirs. The combined Eagle Ford and Woodbine (Eaglebine) reservoir can sometimes exceed 1,000 feet in thickness. These reservoirs are present at depths between 6,500 and 15,000 feet in East Texas. In some areas, the Eaglebine contains a large percentage of silica-rich sands interbedded in organic rich shale and carbonate layers.

This paper investigates the reasons as to why same hydraulic fracturing techniques should not be applied necessarily for every well in the same geological area. Furthermore, it demonstrates how we can exploit the localized reservoir behavior to plan for future wells despite limited data availability. Data from mud logs, well logs, and cores, including mineralogy and geomechanical data are integrated to build the localized reservoir characterization model that can be used to plan how each individual well should be hydraulically fractured. The model provides information such as location of organic-rich zones, brittle zones, and ductile zones in a geological area. Lastly, it recommends the type of fracture fluid that can yield a successful stimulation operation in ductile or brittle zones.
Limitations of Current Type Curves in Characterizing SRV; and Development of EFR Type Curves
Authors: Barzin Yalda , Mattar Louis
Published: February 2017

Success of the unconventional multi-fractured horizontal well revolution depends on creation of a Stimulated Reservoir Volume (SRV). Advances in stimulation technology have been geared towards creating increasingly larger SRV's. However, the techniques for evaluating the size and shape of the SRV from production data analysis have not kept pace, and need to be improved.

In this paper, we review the diagnostic methods that are currently used, and share learnings obtained from analyzing hundreds of unconventional wells from different unconventional plays. We describe the existing specialized analyses, namely plots utilizing square-root of time (and other time functions), along with type curves that were developed for Compound Linear Flow. We demonstrate that even though these type curves do not account for SRV, they can still be used partially to learn about the SRV characteristics.

We have studied the behavior of the EFR (Enhanced Frac Region) model and show how it deviates from the Compound Linear Flow type curves. We demonstrate that what is often considered to be linear flow is only a transition between two flow regimes and results in misinterpretation of the linear flow parameters, and consequently, of SRV properties.

We have developed a new EFR type curve that helps characterize the SRV. It should provide a better understanding and interpretation of the currently accepted multi-fractured horizontal well/reservoir system, and improve the diagnostic analysis that precedes and reinforces modeling.
CO2-Oil Interactions in Tight Rocks: An Experimental Study
Authors: Habibi Ali , Yassin Mahmood Reza , Dehghanpour Hassan , Bryan Donald
Published: February 2017

This paper presents comprehensive rock-fluid experiments to study the possibility of oil recovery improvement when CO2 is injected as a fracturing fluid in the Montney tight-oil play, located in the Western Canadian Sedimentary Basin. This study consists of four phases: In phase 1, we conduct constant composition expansion (CCE) tests with different CO2 concentrations using a PVT cell. In phase 2, we visualize CO2-oil interactions at reservoir pressure and temperature in a custom-designed visual cell. Then, we conduct SEM/EDS analysis on the solid precipitates in the visual cell due to CO2-oil interactions. In phase 3, we soak the oil-saturated core plugs in the visual cell, pressurize the cell with CO2, and measure the oil recovery. In phase 4, we conduct cyclic CO2 tests using a core flooding system, and measure the oil recovery. We also evaluate the oil viscosity and wettability of the core plugs before and after cyclic CO2 process.

The results of the CCE tests conducted using the PVT cell and visualization tests conducted using the visual cell show that CO2 can significantly dissolve into and expand the Montney oil. The results of the CO2 soaking tests and cyclic CO2 process show that the oil swelling due to CO2-oil interactions results in high oil recovery factor from the oil-saturated core plugs. In addition, we observe solid precipitates due to CO2-oil interactions at the bulk-phase conditions in the visual cell. SEM/EDS analysis on the solid precipitates show the existence of carbon and sulfur, the main components of asphaltene. The results of IP-143 test confirm the formation asphaltene when the Montney oil contacts CO2 at reservoir conditions.
The Impact of Completion Technique on Well Performance
Authors: Anderson D. M. , Thompson J. M. , Popp M. , Behmanesh H. , Liang P.
Published: February 2017

There are several different technologies available for completing and stimulating multi-stage horizontal wells. By far the most common of these is to use a cemented liner with multiple perforation clusters treated simultaneously in a single stage (plug-and-perf). One alternative method gaining popularity also employs the use of a cemented liner but with sliding sleeves allowing for single point entry into the formation (pinpoint). The objective of this paper is to compare the expected and observed reservoir performance resulting from each of these approaches.

To accomplish the objectives, two methods are appliedtheoretical and experimental. The theoretical approach uses a hydraulic fracture simulator to predict fracture geometry for both plug-and-perf and pinpoint completion techniques for a predefined set of treatment parameters. A reservoir simulator is then used to predict production and ultimate recovery for each case. The experimental approach involves choosing a drilling spacing unit (DSU) where these two completion techniques have been applied (in close proximity) while controlling, or normalizing for, as many other reservoir and completion variables as possible. The well performance data is analyzed using rate transient analysis (RTA), and the results compared to the predictions made by the theoretical models.

Theoretical modeling predicts that slightly better reservoir performance ought to be obtained in pinpoint completions, over plug-and-perf. Experimental (empirical) analysis of actual well performance data supports the theoretical predictions directionally, but significantly exceeds the uplift predicted by the theoretical models. Ideally, the experimental data should be collected under controlled conditions. In reality, this is not the case as operations on a typical well pad (as is the case in this study) are continuously subjected to disturbances, unconstrained variables and incomplete and/or inaccurate measurements. Thus, results from RTA are somewhat subjective and error prone. The confidence of these results improve dramatically as the sample data set increases.

To our knowledge, this work represents the first objective comparison of different completion types using rate transient analysis as an evaluation tool. The experimental benchmarking procedure introduced in this work is novel and represents a significant improvement over existing industry standards for understanding how completion technology can impact well performance.
Building Type Wells for Appraisal of Unconventional Resource Plays
Authors: Miller P. , Frechette N. , Kellett K. D.
Published: February 2017

Building type wells for unconventional resource plays in early phases of development is a significant challenge for industry. Although the application of statistical techniques to type wells is gaining acceptance, it is often unclear to evaluators how these techniques can be applied to accurately capture the full range of uncertainty in the average single well estimated ultimate recovery for a geologic subset. This lack of clarity in proper methodology is especially apparent when very few analogue wells exist, or a very limited amount of production history is available. The objective of this paper is to present an integrated workflow that can be used to build P90, mean, and P10 type wells, which represent the range of potential outcomes for the geologic subset in an unconventional resource play. Through this workflow, the evaluator obtains an understanding of the key value drivers for a geologic subset and can compare and rank different geologic subsets. The proposed workflow is illustrated with an example from a North American unconventional play.
Investigation of Shale Pore Compressibility Impact on Production with Reservoir Simulation
Authors: Davudov Davud , Moghanloo Rouzbeh Ghanbarnezhad , Lan Yuzheng , Vice Dalton
Published: February 2017

This study introduces a novel outlook on a shale pore system and pore compressibility values in shale gas formations. Pore volume compressibility is one of the vital reservoir properties in order to optimize the production of hydrocarbons in an accurate way in shale formations. However, the use of pore compressibility is often oversimplified in reservoir analysis. Correcting for pore compressibility allows for improved accuracy in both geomechanic aspects and hydrocarbon reserve evaluation. In this work, we analyze pore compressibility values and its impact on production performance for several major North American shale plays.

We divide porosity of the system into accessible and inaccessible pores, and incorporate inaccessible pores with grains into the part of the rock that is not accessible. Generally speaking, accessible pores contribute to flow directly while inaccessible pores do not.

We present a mathematical model using Mercury Injection Capillary Pressure (MICP) data to determine accessible pore and inaccessible part of the rock (IRP) compressibility as a function of pressure. During MICP testing in a typical shale sample, the rock sample experiences conformance, compression, and intrusion as effective pressure increases. We characterize the compressibility value based on MICP data as a function of pressure. The calculated compressibility values for accessible pores generally appear to be much greater (two to three orders of magnitude) than those of IRP.

Next, we studied how calculated accessible pore compressibility can affect gas recovery in shale gas plays. Numerical approach is used to evaluate impact of compressibility on gas production. Reservoir compaction is generally regarded as total pore compressibility, which has a value ranging within the 10−6 magnitude. By recognizing the part of the pore system that actually contributes to production and identifying its compressibility, we can substitute total pore compressibility with accessible pore compressibility. Our results indicate that substitution of accessible pore compressibility with total compressibility can significantly change the reservoir behavior prediction. Moreover, results suggest that at initial stage high compressibility value will contribute to production significantly. However, at the same time, this high compressibility in shale matrix, will lead to pore throat closure, thus loss of connectivity at later time.

The outcome of the paper changes the industry’s take on prediction of the reservoir performance, especially the rock compaction mechanism. This study finds that shale production owing to rock compaction is in fact much greater than what has been often regarded. Having a better understanding of pore compressibility effect leads to better reservoir estimation, production prediction, and less failed wells due to economic feasibility inaccuracies.
Rock-Fluid Interactions in the Duvernay Formation: Measurement of Wettability and Imbibition Oil Recovery
Authors: Begum Momotaj , Reza Yassin Mahmood , Dehghanpour Hassan , Dunn Lindsay
Published: February 2017

In this study, we evaluate the wettability of shale samples drilled in the Duvernay Formation, which is a source-rock reservoir located in the Western Canadian Sedimentary Basin (WCSB). We use reservoir oil and brine to conduct air-liquid contact angle and air-liquid spontaneous imbibition tests for wettability measurements. We characterize the shale samples by measuring pressure-decay permeability, effective porosity, initial oil and water saturations, mineralogy, total organic carbon (TOC) content, and conducting rock-eval pyrolysis tests. We also conduct Scanning Electron Microscope (SEM) and energy-dispersive x-ray spectroscopy (EDS) analyses on the shale samples to characterize the location and size of pores. After evaluation of wettability, we conduct soaking experiments. First, we measure liquid-liquid contact angles for the droplets of the soaking fluids and reservoir oil equilibrated on surface of the rock samples. Then, we immerse the oil-saturated samples in the soaking fluids with different compositions and physical properties. The we record the oil volume produced due to spontaneous imbibition of the soaking fluids. The soaking fluids are characterized by measuring surface tension, interfacial tension (IFT), viscosity, and pH. We analyze the results of soaking tests and investigate the controlling parameters affecting oil recover factor (RF).

The results of wettability measurements demonstrate that the shale samples have stronger wetting affinity to oil compared with brine. The positive correlations of TOC content with effective porosity and pressure-decay permeability suggest that the majority of connected pores are present within the organic matter. Organic porosity may explain the strong oil-wetness of the shale samples. The SEM/EDS analyses also show the abundance of organic nanopores within organic matter. The results of liquid-liquid contact angle tests show that a reduction in IFT of the soaking fluid leads to an increase in wetting affinity of rock to soaking fluid. The results also show that oil RF is higher for soaking fluids with lower IFT, which can be explained by wettability alteration. The shale samples have higher wetting affinity to soaking fluids with lower IFT, leading to an increase in the driving capillary pressure and, consequently to higher oil recovery by spontaneous imbibition. In addition, comparing the results of air-brine imbibition with soaking tests suggests that adding surfactant to the soaking fluid may alter the wettability of organic pores towards more water-wetness, leading to the displacement of oil from hydrophobic organic pores.
Flexible Cement Slurry Survives Multistage Hydraulic Fracturing Treatment
Authors: Hudson M. D. , Sheperd P. , Ricci J.
Published: February 2017

Multistage hydraulic fracturingturing treatments in unconventional wells have greatly increased the number and magnitude of stress cycles that must be withstood by primary cement jobs. The stress cycling of hydraulic fracturingturing on Portland Cement, with its intrinsic mechanical properties, may present a risk to long-term well integrity. By modifying the mechanical properties of the set-cement to make it more flexible, the risk of compromising well integrity during hydraulic fracturingturing treatments can be reduced.

The mechanical properties of set-cement designs can be tested in a laboratory setting. This allows quantification of the compressive strength, tensile strength, Young's modulus, and Poisson's ratio of the set cement. Hydraulic fracturingturing design software can be used to quantify the pressure and temperature cycles to which the inner diameter of the primary casing string will be subjected. A mathematical model is used to predict the potential risk of mechanical failure of the set cement based on the mechanical properties and the pressure and temperature cycles of the expected treatment. The mathematical model identifies risk of failure in tension, compression, and de-bonding.

By adding flexible materials to Portland Cement in a reduced water, tri-modal particle-size-distribution blend, the Young's modulus can be reduced while relatively high compressive and tensile strength is maintained. According to the mathematical model, a cement sheath with these properties is at a low risk of mechanical failure in any of the three failure modes up to a certain hydraulic fracturingturing pressure. Wireline logging tools use ultrasonic waves to measure acoustic impedance and flexural attenuation for cement evaluation. These readings are used to assess the integrity of the cement sheath in a 360° solid/liquid/gas map around the casing. These logging data can be used to determine the presence and extent of damage to the cement sheath during the hydraulic fracturingturing operation.

A hydraulic fracturingturing treatment was applied to a well cemented with optimized flexible and trimodal properties. Cement evaluation logs were run before and after treatment for comparison. The post-fracturingturing log showed no damage to the annular cement sheath.