bluuebunny/crossref_metadata_2025 huggingface dataset:
Kv4.2 knockout mice display learning and memory deficits in the Lashley maze
Authors: Smith Gregory D. , Gao Nan , Lugo Joaquin N.
Published: October 2016

Background: Potassium channels have been shown to be involved in neural plasticity and learning. Kv4.2 is a subunit of the A-type potassium channel. Kv4.2 channels modulate excitability in the dendrites of pyramidal neurons in the cortex and hippocampus. Deletion of Kv4.2 results in spatial learning and conditioned fear deficits; however, previous studies have only examined deletion of Kv4.2 in aversive learning tests.

Methods: For the current study, we used the Lashley maze as an appetitive learning test. We examined Kv4.2 wildtype (WT) and knockout (KO) mice in the Lashley maze over 4 days during adulthood. The first day consisted of habituating the mice to the maze. The mice then received five trials per day for the next 3 days. The number of errors and the time to the goal box was recorded for each trial. The goal box contained a weigh boat with an appetitive reward (gelatin with sugar). There was an intertrial interval of 15 minutes.

Results: We found that Kv4.2 KO mice committed more errors across the trials compared to the WT mice p<0.001. There was no difference in the latency to find the goal box over the period.

Discussion: Our finding that deletion of Kv4.2 resulted in more errors in the Lashley maze across 15 trials contribute to a growing body of evidence that Kv4.2 channels are significantly involved in learning and memory.
Influence of Heat Treatment on the Mechanical Properties of Ni Films on 430 Stainless Steel Substrate
Authors: Pan Yong , Cui Junwei , Lei Weixin , Zhou Jie , Ma Zengsheng
Published: October 2016

Effects of heat treatment on the mechanical properties of Ni films on 430 stainless steel substrate were investigated. The Ni films were annealed at heat treatment temperatures ranging from 0 °C to 800 °C for 2 h. The surface morphology, composition, and texture orientation of Ni films were studied by scanning electron microscopy, energy dispersive spectrometry, and X-ray diffraction. The load–indentation depth curves of Ni films before and after heat treatment were measured by using nanoindentation method. In conjunction with finite element modeling and dimensional analysis, the stress–strain relationships of Ni films on 430 stainless steel substrate at different temperatures are successfully obtained by using a power-law hardening model.
On case and tense: The role of grounding in differential subject marking
Authors: Lestrade Sander , de Hoop Helen
Published: October 2016

In this paper, we propose a uniform motivation for subject case alternations that align with distinctions in tense and aspect and those that align with a distinction between stage- and individual-level predication. We argue that both follow from an economical use of case marking that is made possible by grounding. If the argument function of an event participant can be determined on the basis of information available in the here and now, the use of case marking can be judged redundant and suspended because of economy.
Soliloquies Divine: God's Self-Addressed Rhetoric in the Old Testament
Authors: Arrington Phillip K.
Published: October 2016

Very little has been written about the quite noticeable tendency of God to address himself in the Old Testament, starting with the opening chapters in Genesis and continuing, intermittently, until 2 Kings. These speeches may very well be the oldest examples we have of what James Hirsh calls “self-addressed soliloquies,” but they cannot be analyzed based on some of the theoretical ideas of Kenneth Burke, Chaim Perelman and Lucie Olbrechts-Tyteca, Augustine (who invented the term), or Harold Bloom. As my analysis of these speeches shows, God's rhetoric in these speeches, his ethos, is highly elliptical, ironic, and contradicts most of what readers expect from a soliloquy.
EFFECT OF DIFFERENT REMEDIATION TECHNIQUES AND DOSAGES OF PHOSPHORUS FERTILIZER ON SOIL QUALITY AND KLEKAP PRODUCTION IN ACID SULFATE SOIL AFFECTED AQUACULTURE PONDS
Authors: Mustafa Akhmad , Sammut Jesmond
Published: October 2016

Acid sulfate soils (ASS) contain sufficient pyrite which, when oxidised following excavation for brackishwater aquaculture ponds, will generate acid and mobilise toxic metals. Production in affected ponds can be low due to poor growth of shrimp and fish, mass mortalities of stock and low plankton blooms. The resultant low soil pH can also cause poor klekap production due to the retention of phosphorus associated with elevated concentrations of Fe and Al in the pond soils. A series of experiments was conducted to determine the effects of different soil amelioration techniques and dosage of phosphorus (P) on soil and klekap production under laboratory conditions. The treatments consisted of two factors. The first factor tested was different techniques for ASS improvement (non-improvement, improvement through liming and improvement through remediation involving forced oxidation of pyrite, flooding and flushing of oxidation products). The second factor tested was phosphorus dosages, that is, with phosphorus and without phosphorus-based fertilizer. Each treatment had three replications. The experiment showed that liming and remediation had the same effect on several soil variables; they raised the soi pH (pHF, pHFOX, pHKCl) and decreased SPOS, Fe and Al. Remediation of ASS decreased retention of P and increased available-P of soil, whereas liming did not show a significant effect on retention of P and available-P in the doses used for this experiment. The interaction between the different soil improvement techniques and phosphorus fertilising showed a significant effect on klekap production with the highest klekap production of 23.21 mg/cm2 found in remediated soil and with a phosphorus fertiliser dosage of 75 kg/ha.
THE EFFECTS OF STORAGE TEMPERATURE AND TYPES OF MEDIA ON THE SURVIVAL RATE OF S. agalactiae BACTERIOPHAGE
Authors: Lusiastuti Angela Mariana , Sumiati Tuti , Priadi Adin
Published: October 2016

The successful effect of phages in phage therapy has been proven by an increase of the presence of phages in survivors. Seven previously isolated phages were used to examine the effects of storage temperature and types of media on their survival rate. Phages PSaT-18, PSaT-19, PSaT-20 and PSaT-21 isolated from a Streptococcosis-infected Tilapia (Oreochromis niloticus) were used in this study. Phages PSaG-1, PSaG-2 and PSaG-3 were isolated from a diseased Gouramy (Osphronemus gouramy). All of the phages were stored in refrigerator at temperature of 8oC and kept in two types of media, Brain Heart Infusion Broth (BHIB) and BHIB enriched with glycerol. To determine the lytic activity of the phages, 20 μL of each phage suspension was poured onto BHIA plate and incubated at 25oC for 24 to 48 hours. The result showed that phages PSaT-18, PSaT-19, PSaT-20 and PSaT-21 have lytic activity against S. agalactiae and S. iniae than phages PSaG-1, PSaG-2, and PSaG-3. Phages PSaT-18, PSaT-19, PSaT-20, and PSaT-21 always survived up to three weeks and phage PSaT-18 in BHIB have the highest potential as a candidate of phage therapy for Streptococcosis.
VARIASI GENETIK HASIL PERSILANGAN NILA BEST DENGAN RED NIFI DAN NIRWANA MENGGUNAKAN PENANDA RAPD
Authors: Iskandariah Iskandariah , Kusmini Irin Iriana , Arifin Otong Zenal , Gustiano Rudhy
Published: October 2016

Penelitian mengenai variasi genetik dari hibridisasi 3 varian ikan nila (BEST, Red NIFI, dan Nirwana) telah dilakukan di Laboratorium Molekuler Biologi, Balai Riset Perikanan Budidaya Air Tawar (BRPBAT) Bogor. Tujuan penelitian ini adalah untuk mengetahui keragaman genetik hasil hibridisasi antara nila BEST, Nirwana, dan Red NIFI dengan menggunakan metode Random Amplified Polymorphism DNA (RAPD). Amplifikasi DNA menggunakan primer OPA-02, OPA-03, dan OPC-05. Hasil analisis menunjukkan bahwa persentase polimorfisme berkisar antara 18,1818%–42,4242%, dengan nilai heterozigositas 0,0733-0,1564 dan jarak genetik antar populasi 0,3735–0,5300. Keragaman genetik tertinggi diperoleh pada hasil hibridisasi antara nila BEST dengan Nirwana. Nilai polimorfisme meningkat sebesar 10,6060% dan heterozigositas 0,0352 pada populasi hasil hibridisasi dibandingkan dengan populasi true breeding. Hal ini menunjukkan bahwa hibridisasi dapat meningkatkan nilai keragaman genetik dari suatu populasi ikan.
MENJADIKAN PERIKANAN BUDIDAYA SEBAGAI INKUBATOR BISNIS MANDIRI: PELAJARAN BERHARGA DARI TAIWAN
Authors: Nugroho Estu
Published: October 2016

Keberhasilan Taiwan dalam bidang budidaya perikanan merupakan suatu hal yang dapat dijadikan contoh pembelajaran dalam pengembangan budidaya di Indonesia, dengan penyesuaian keadaan di Indonesia. Pada prinsipnya keberhasilan Taiwan dipengaruhi oleh beberapa faktor, di antaranya adalah: kejelian dalam memilih komoditas, kesuksesan penerapan teknologi tepat guna serta peranan yang kuat dari pemerintah, perguruan tinggi, dan asosiasi dalam bidang perikanan. Komoditas yang mempunyai nilai ekonomis yang tinggi menjadi acuan pengembangan produk khususnya ekspor. Teknologi dengan memanfaatkan bahan baku serta sumberdaya alam yang ada di daerah setempat merupakan andalan pembudidaya dalam menaikkan produktivitas melalui penyediaan air yang berkualitas, pakan yang ramah lingkungan, benih yang berkualitas serta penggunaan bahan herbal untuk kekebalan. Penyediaan infrastruktur sarana dan prasarana, penyediaan dana yang mudah dan murah serta jalur transfer teknologi yang jelas mempunyai peranan yang penting.
Number System of the Noun Phrases Modified by Demonstrative Pronouns in Mandarin Chinese
Authors: Yu 刘宇 Liu
Published: October 2016

This paper aims to account for the number system of the noun phrases modified by the demonstrative pronouns in Mandarin Chinese. The cross-linguistic analysis indicates that the noun phrases modified by the demonstrative pronouns in both English and Mandarin Chinese have developed a rigorous grammatical system to represent the property of number. However, whereas the English noun phrases highlight the distinction between singular and plural forms, the Chinese ones tend to distinguish specific quantity from indefinite quantity. A new classificatory framework is proposed to analyse the ‘Demonstrative Pronoun + NP’ structure in Mandarin Chinese, and to explain its unique grammatical behaviours.
Extraction and characterization of liver oil from silky shark
Authors: Rozi Anhar , Suseno Sugeng Heri , Jacoeb Agoes Mardiono
Published: October 2016

Silky shark liver was 10-15% of its body mass and 50% of oil is contained in the liver. The aimed of
this study was to determine heavy metal content, fatty acid profile on raw material, extraction of its oil, and
parameter of oxidation. The method of heavy metal test stated on the SNI and fatty acid analysis referred
to AOAC. The extraction was oven methode at 50, 60, 70, and 80°C in 8 hours. Cadmium (Cd) as the
highest heavy metal content with 0.88±0.01 ppm, SFA was 18.46% composed by palmitic acid dominantly
(12.59%). The MUFA was 24.54 % with the highest oleic acid (17.86%). PUFA was 19.11 % that consist of
DHA (14.35%) as the most abundantly present while EPA was 1.50%. Shark liver oil which was extracted
at 50°C had the highest yield (24.47%). The oxidation of silky shark liver oil extraction indicated the best
treatment at 50°C with peroxide value (PV), p-Anisidine value (p-AV), percentage of free fatty acid (% FFA),
acid value (AV), and total oxidation (TOTOX) were 7.26±1.27 mEq/kg, 16.79±0.28 mEq/kg, 5.47±0.12%,
10.88±0.25 mg KOH/kg, and 31.31±2.26 mEq/kg respectively.
Chemical and Microbiology Characteristic of Smoked and Seasoned African Catfish Fillet Affected by Canning Processing
Authors: Murda Yusuf Kalingga , Husni Amir , Budhiyanti Siti Ari , Herwati Ervika Rahayu Novita
Published: October 2016

African catfish (Clarias gariepinus) many cultivated by the farmers, however if not treated quickly
damaged. One treatment that can maintain quality product african catfish is by smoked and canning. The
aim of this study was to determine the chemical and microbiological characteristics of smoked African
catfish fillet with seasoning packaged cans during storage. Preparation of research carried out by soaking
the African catfish fillet into seasonings and liquid smoke concentration of 10% by immersion for 1
minute, and then next process of curing and drying. Products that are ripe weighed 110 g and signed
into cans sized Ø 301x205. Added medium brine concentration 5% and vegetable oil as much as 100
ml, a process exhausting and seaming. The last stage is performed a sterilization process (126oC for 20
minutes), cooling and incubation (24oC for 2 weeks). Observations deterioration of product quality of
smoked African catfish fillet with seasoning performed at weeks 0, 2, 4, 6 and 8. Tests conducted include
chemical test which includes test TVB, pH and peroxide value and microbiological testing in the form
of TPC. The results showed that the combined treatment of the fumigation and the addition of medium
(saline 5% and solution of vegetable oil) combined with treatment canning able to maintain product
quality of smoked African catfish fillet with seasoning, based TVB, pH, peroxide value and TPC during
storage.
Los "prima", "secunda" y "tertia spolia opima"
Authors: Riesco Álvarez Hipólito Benjamín
Published: October 2016

Todos los despojos opimos conquistados por los generales romanos fueron consagrados a Júpiter Feretrio; pero con ocasión de cada uno de ellos los dedicantes tuvieron que ofrecer un sacrificio a Júpiter, a Marte y a Quirino, respectivamente. La calificación de prima, secunda y tertia respondería, en principio, a cuestiones cronológicas y, en segundo lugar, a cuestiones de importancia, a juzgar por los sacrificios y la remuneración que la ley de Numa fijaba para cada caso.
El concepto de "sagrado" en latín: el adjetivo "sacer" en los diez primeros libros de Tito Livio
Authors: Barrio de la Fuente Carmen
Published: October 2016

El concepto de "sagrado" en latín: el adjetivo "sacer" en los diez primeros libros de Tito Livio
In Vitro Fertilization Outcome After Intracytoplasmic Sperm Injection with Fresh and with Frozen-Thawed Epididymal Spermatozoa
Authors: Lubis Hilma Putri
Published: October 2016

Introduction

Testicular epididymal sperm aspiration (TESA) is one of the method  to retrieve sperm from the testes in men with azoospermia. The aim of the study is to compare the In vitro fertilization (IVF) outcome of intracytoplasmic sperm injection (ICSI)-ET cycles with fresh testicular epididymal spermatozoa obtained on the same day with  oocyte retrieval and with frozen-thawed testicular epididymal spermatozoa.

Material & Methods

A retrospective comparative analysis of  patients who underwent fresh TESA and frozen-thawed TESA in ICSI-ET cycles from January 2012 to December 2014 in Halim Fertility Center was done. Fresh testicular epididymal sperm aspiration (fresh TESA) was performed on the same day with oocyte retrieval in 28 cycles and the frozen-thawed testicular epididymal sperm aspiration (frozen-thawed TESA) was used in 30 cycles.  

Results

The two groups were comparable in terms of the ages of male and female patients, etiology of infertility and duration of infertility. Fertilization rates in fresh TESA group were 53,5% and in frozen-thawed TESA group, fertilization rates were 50%. There was no statistically significant difference between the groups. Clinical pregnancy rates in fresh TESA group were 35,7%  and in frozen-thawed TESA group, clinical pregnancy rates were 26,7% and statistically there was no significant difference between the groups.

Conclusion
There is no significant difference in the in vitro fertilization outcome of intracytoplasmic sperm injection (ICSI)-ET cycles between fresh TESA and frozen-thawed TESA .
Correlation between Follicular Fluid’s Androgen Level and Fertilization Rate in Poor Responder Patients Undergone IVF: A Prospective Cohort Done in Yasmin IVF Clinic, Jakarta, Indonesia
Authors: Wiweko Budi
Published: October 2016

Introduction Androstenedione (A4), testosterone (T), and dehidroepiandrosterone (DHEA) are known to be involved in folliculogenesis and follicular maturity. Lower follicular androgen levels in poor responder due to malfunctioned granulosa and theca cells and decreased inhibin B production will decrease FSH and LH. However, androgenic follicular fluid might also induce follicular atresia, decreased oocytes viability, thus affecting fertilization. The aim of current study is to find the correlation between intra-follicular androgen levels and fertilization rate, specifically in poor responder whom contributed in 84% cancelled cycle.

Material and Methods This prospective cohort study was done at Yasmin IVF Clinic, Jakarta, Indonesia, in January 2014-March 2015. Infertile women undergone IVF were asked to participate, grouped into poor responder and other, and the androgen levels in the follicular fluid of each consenting patients were measured.

Results From total 62 patients, aged 23-47 years old (37.6±5,068), there were 21 poor responders, whereas the other 41 patients with other indication. In poor responder group, levels of androstenedione, testosterone, and DHEA were 50.8 – 272.3 (103.5 ± 59.9), 383.2 – 1747.9 (1114.4 ± 373.2), 11.3 – 454.8 (151.3 ± 96.8), whereas in other group the androgen levels were 44.3 – 326.8 (95.1 ± 61.2), 414.1 – 1463.7 (976.9 ± 258.4), 44.6 – 265.8 (132.7 ± 61.3) with the correlation with fertilization rate 0.609, 0.095, and 0.361 respectively.

 

Conclusion Correlation between follicular androgen levels and fertilization rate found to be not significantly different. The low number of subjects might cause this result, as well as the presence of bias, e.g.male factor and endometriosis might also affect fertilization. A multi-center study with larger sample size added with thorough analysis is needed to reconfirm current data.
Do Personality Traits Matter in Chinese Academics’ Teaching Approaches?
Authors: Zhang Li-fang
Published: October 2016

This research aimed at identifying the statistically predictive relationship of personality traits to teaching approaches. The NEO Five-Factor Inventory and the Approaches to Teaching Inventory were administered to 268 academics from six elite universities in mainland China. Results showed that personality traits significantly contributed to teaching approaches beyond gender, type of institution, and taught academic discipline. Specifically, as expected, openness was beneficial to the conceptual-change teaching approach, whereas neuroticism was conducive to the information-transmission teaching approach. Furthermore, extraversion was related to the conceptual-change teaching approach, whereas agreeableness was associated with the information-transmission teaching approach. Implications of these findings are discussed with respect to academics and university senior managers.
The Phonological Word and Stress Shift in Northern Kurmanji Kurdish
Authors: Mohammed Hasan Aveen
Published: October 2016

It is generally believed that stress in Kurdish is word-final. However, closer examination reveals several kinds of exceptions. This study proposes a unified analysis of regular and irregular stress patterns in Northern Kurmanji. It analyses the stress-assignment rule on the basis of a framework of prosodic phonology that divides the representation of speech into hierarchically organised units. It proposes the phonological word as the domain of stress rule and a number of other phonological processes such as glide insertion, resyllabification, vowel deletion, vowel shortening. Additionally, it proposes the cyclic analysis as the method of the rule application. Cases of stress rule violation are considered as instances of stress-shift which are conditioned by different phonological and syntactical factors or they can be accounted for by using recursive structure and phrase stress rule.
Retail banking in the Czech Republic – a comparison of consumer prices between 2011 and 2014
Authors: Rod Aleš , Čermáková Klára
Published: October 2016

The banking sector has been developing very rapidly in the past century. In Czechoslovakia as well as in other post-communist countries, the development differed due to specifics of the centrally planned system with a monobank and no official competition in retail banking. This specific factor influenced the development of the banking industry after 1990, when big banks used information asymmetry in individual parts of profit seeking (esp. income diversification). Growing competition, development of information technology and growing literacy of bank customers have decreased retail prices only after 2011, as shown by performed comparison of retail prices of banking services in the examined period. Using comparison of retail banking clients clusters the paper identifies factors of significant decrease of retail prices of bank services. We focus on discussing these factors, mainly growing competition, growing financial literacy, lowering transaction costs. This paper raises a very important question whether the “big four” on the retail banking market would keep their hegemony or the competition on this market would prevail. To answer this question is the aim of our next research.
Does Firm Age Affect Profitability? Evidence from Turkey
Authors: Akben-Selcuk Elif
Published: October 2016

The objective of this study is to investigate the impact of firm age on the profitability of Turkish firms listed on Borsa Istanbul. Using a dataset covering the years between 2005 and 2014 and consisting of 302 non-financial firms per year on the average, a fixed effects model with robust standard errors is estimated. Results reveal that there is a negative and convex relationship between firm age and profitability measured by return on assets, return on equity or gross profit margin. This suggests that younger firms start to see a decline in their profitability from the beginning but they may become profitable again at an old age. Implications are provided.
"Vaguely Right or Precisely Wrong?": Making Probabilistic Cost, Time, and Performance Estimates for Bluefields Appraisal
Authors: Surovtsev Dmitry , Sungurov Anton
Published: October 2016

We conducted a practical case study that aims at estimating the shapes and parameters of probability distributions for key cost, time and activity performance inputs required by a risk, resource, and value simulator to conduct a stochastic valuation of a new exploration asset.

We analyzed a sample of 73 shallow offshore fields in Australia retrieved from a global field-by-field database that includes reserves, production profiles, financials, valuation, breakeven prices, ownership and other key metrics for global oil and gas fields, discoveries and exploration licenses.

The reviewed facilities concepts includes 40 steel platforms, 2 concrete gravity-based developments, 10 projects with extended reach drilling, 4 FPSO, and 17 subsea tie-backs. The aggregate CAPEX of projects in the sample over 1965–2015 is USD 99.1 billion (in nominal terms), which is commensurate with the total asset size of the Australian offshore petroleum industry.

We estimate probability distributions for all full-cycle parameters required to generate Monte Carlo CAPEX, OPEX, and production profiles. In particular, these include facility CAPEX per unit peak, development phase duration and scheduling rules, drilling expenditures per barrel of oil equivalent, cost of exploration and appraisal wells, OPEX-to-CAPEX ratio, abandonment cost ratio, fraction of hydrocarbons produced yearly at plateau, fraction of hydrocarbons remaining at end-of-plateau, terminal production rate, and fraction pre-drilled wells. Most of the above were found to be log-normally distributed.

The paper presents a simple yet robust workflow relying on real industry data that enabled assessing value, risks, and uncertainties of upstream assets at exploration and early appraisal stages. It can be seamlessly extended to other basins owing to a rich coverage of the online field analogs database.

The ultimate outcome of the study—a probabilistic value assessment of new exploration asset—represents a modern appraisal methodology relying on a corporation-wide software platform.
A Novel Strategy for Restoring the Well Integrity by Curing High Annulus-B Pressure and Zonal Communication
Authors: Ansari Arsalan A. , Ringrose David , Libdi Ziad , Larsen Arne G.
Published: October 2016

The petroleum industry is performing extensive research into rectifying structural well integrity issues, mainly caused by migration of hydrocarbon fluids to surface through microchannels, due to poor cementation, resulting in the inability to provide integral barriers in the 9⅝″ casing × 12¼″ hole annulus. As a consequence, the well life can be extended and the older wells can be restored back to production and injection, resulting in long term fulfilling of the increasing global demand for additional energy requirement. Annulus-B Remediation using HydraWell Technology is one of the innovative approaches that can be utilized in wells to provide strong integral cement barriers behind the 9⅝″ production casing to prevent reservoir fluids migrating to surface. This approach is gaining increased popularity due to a number of economic and environmental advantages such as restoring the well production/injection with minimum workover costs and risk due to less complex operations, mitigate environmental concerns by avoiding excessive steel cuttings like section milling and eliminating the complexity associated to re-entry risk as incase of section milling.

The research utilizes a novel technology to execute a repair of wells with failed Annulus-B barrier integrity by providing integral cement barriers in the 9⅝″ × 13⅜″ casing annulus above the reservoir for wells experiencing migration of hydrocarbons from reservoir through the 9⅝″ × 13⅜″ casing annulus. The planned methodology starts with completion recovery followed by running noise, temperature and cement bond logs in order to evaluate the cement quality behind 9⅝" casing above the reservoir.

Findings from the noise/temperature logs and oil sample evaluation indicated that oil is migrating from the reservoir, through 9⅝″ × 13⅜″ casing annulus, dripping at surface through the 30″ conductor pipe. The cement bond logs indicate poor cement behind 9⅝″ casing above the reservoir. Therefore, Remediation technology was successfully utilized as it delivers effective jet washing and subsequent cleaning of the annular space using specialized tools and thereafter spraying cement to create a 100-feet competent cement barrier behind the casings for effective isolation and the prevention of pressure communication to the surface via Annulus-B. Furthermore, a 7″ short tie-back was installed over the perforated cemented interval. Hence, the 9⅝" casing was re-established as a well barrier element in the well, allowing the injection rate for the well to be restored.

This strategy may be developed as a very cost effective technology as it saves the operator approximately 5-8 days per well with associated significant CAPEX and OPEX savings by avoiding additional costs associated with complexity of operations in section milling. It is feasible to be applied in offshore wells requiring remediation of failed Annulus-B integrity with reduced rig time and the associated costs with minimum environmental risk.
Evaluation of Natural Fracturing to Develop Induced Fracturing Methods Best Suited for Low-Permeability Reservoirs
Authors: Maganov N. U. , Khisamov R. S. , Bazarevskaya V. G. , Podavalov V. B.
Published: October 2016

Main fields in the Republic of Tatarstan have entered the closing stage of development characterized by high extent of reserves depletion (86 % of OOIP) and increase of the share of unconventionsl hard-to-recover reserves (from 33 % to 80 %). A considerable portion of PJSC TATNEFT’s unconventional reserves (36 %) is found, primarily, in carbonate and carbonate-silicious (shale) low porosity/permeability or fractured reservoirs, which are very challenging targets. In this light, study of low-permeability and porous reservoirs has recently acquired a prime importance. Comprehensive studies are needed to understand stress and strain properties of reservoir rocks in challenging geomechanical in-situ conditions.

To understand fracturing pattern of carbonate reservoirs in Tatarstan, the Company has been employing different survey methods, including aerial and space imagery, side-view seismic location (SVSL), offset vertical seismic profiling, tracer surveys, core analysis, including oriented and quick capture cores, 3D CDP seismic survey. Particular attention has been given to analyses of drilling troubles and vertical and horizontal wells’ performance. The results obtained make it possible to select optimal orientations of horizontal wellbores with a view to maximize future production.

This paper presents the Bavlinskoye oil field case study. Recommendations on downhole surveys are presented, as well as guidelines to select an optimal orientation of a horizontal wellbore in fractured reservoirs.
TAML-5 Intelligent ERD Offshore Well: A Case Story of Successful Application in the North Caspian
Authors: Ruzhnikov Alexey , Latypov Artur , Dubovik Alexander , Zvyagin Vasily
Published: October 2016

The TAML-5 intelligent extended reach drilling (ERD) offshore well was the first of this type in the North Caspian Sea. The initial preparation and detailed follow up allowed to complete the well in a timely manner, without non-productive time and without deviation from the plan. This paper discusses the methodology used to prepare for the well construction process including the thought process, risk management, contingency planning, challenges faced, engineering and management solutions, results obtained and lesson learned.

To ensure an adequate level of readiness, the preparation started early in advance. The process included global offset analysis of similar wells from around the world. Then in depth engineering study of every operation was performed by splitting all activities in subtasks and reviewing all details. This resulted in strategy for well integrity and contingency plans for every operation and tracking of equipment and tools from the factory to the rig. To ensure the consistency of all phases, a multidisciplinary team was set up and followed the well from beginning to end.

The detailed operational procedures led to a deep understanding of the process by all involved parties. This was a vital part of the process when initial plans had to be changed and re-worked. While, it was not possible to simply implement the results of the large offset analysis, it provided a solid engineering basis for all decisions taken. Even though the contingency plans were not used on this specific well, the post job analysis showed that it is necessary to keep the same level, or even higher, of contingency planning for future wells.

The output from this paper is the thought processand the actual methodology, including the special aspects that needed to be taken into account for the proper preparation and execution of a trouble free TAML-5 ERD well. The methodology can be implemented in any field worldwide, specially on multilateral wells with high-level completions.
Successful Application of In-Situ Time-Delayed Non-Aqueous Drilling Fluid Filter Cake Removal System Offshore Caspian Sea
Authors: Khalilov Ruslan , Salimov Azar , Samarskiy Alexey , Kharitonov Andrey
Published: October 2016

A major national oil company in the Republic of Azerbaijan began drilling and production in a new field where it had little previous offset knowledge. The service company contracted by the operator recommended the use of an oil-based drilling fluids system to significantly reduce operational risks and costs based on its 5 years of experience in the region. Central to all field developments is the challenge of maximizing production. Here, this was addressed through a technical process using a sequence of steps for laboratory testing, risk assessments, and design of service. As a result, the operator approved the use of the non-aqueous reservoir drill-in fluid system and an in-situ time-delayed breaker system (ISTDBS) treatment for all future wells in the field.

After running standalone screens, the operator's wells were displaced with 1.67-specific gravity (SG) CaBr2 brine, and operations were performed to spot the ISTDBS to remove the filter cake deposited by the drill-in fluid and thus maximize productivity. The ISTDBS consists of the following components: carrier fluid (brine), spacer (viscosified), surfactant/solvent, pH-control chemical, shale stabilizer, and filter-cake removal agent (acid precursor). The challenge of using breaker technology for non-aqueous filter cake removal is the efficiency of the surfactant and acid hydrolysis to work in tandem. Laboratory testing protocols were used for validation of the treatment.

In total, six treatments have been performed successfully to-date, showing a 35% increase in the operator's productivity index (PI) from that predicted for wells treated with the ISTDBS. Compared to previously drilled offset wells in the field, the rate of production for the first well treated with the ISTDBS showed a 6.8 fold increase.
Hybrid High Dogleg Rotary Steerable System: New Approach for Through-Tubing Rotary Drilling and Deep Kick-Off wells in the Gullfaks Field, North Sea
Authors: Nadezhdin M. , Koberg U.
Published: October 2016

The goal for TTRD wells and deep kick-off sidetrack wells is to reach the pay zone with one single section. A geological target is often located at a significant distance from the kick-off point, demanding a well path profile with a medium/high radius curve followed by an extended horizontal section. In the past a two run strategy was considered to be the right choice for similar well profiles in Gullfaks field: a motor BHA was used to drill the curve, and a rotary steerable system to drill the horizontal interval. Introduction of the new high dogleg rotary steerable system made it possible to apply the benefits of continuous rotation (faster drilling, smooth wellbores with full directional control and better hole cleaning) to trajectories previously only drillable by downhole mud motors due to high dogleg requirements. The paper describes a new approach for drilling challenging highly deviated reentry wells in one run on example of a one particular TTRD well drilled in North Sea.
Experimental Studies and Analysis of Gas-Jet Device's Operation Characteristics for Oil and Gas Production in Abnormal Operating Conditions
Authors: Fedorov Aleksei E. , Verbitsky Vladimir S. , Goridko Kirill A.
Published: October 2016

Nowadays one of the most actual issues in oil & gas production on the fields is increasing of workover interval, especially in conditions of underdeveloped infrastructure of petroleum objects.

In this paper the gas-jet technologies of the well reactivation and the well operation in abnormal operational conditions are proposed to solve actual problems of hydrocarbons (HC) production. This method is proposed as alternative of traditional jet pump (JP) technology.

Analysis of current theories and practices of jet device (JD) application illustrated that today the least researched JD are JD for ejection passive fluid by power high pressure gas. They are named gas-jet devices (GJD). In this connection experimental studies of GJD were carried out.

In this paper the results of complex experimental studies of gas-jet gas devices (GJGD) and two-phase gas-jet liquid devices (GJLD) and summarized characteristics of their work are described.

As result of theoretical analysis and experimental studies optimal design of sonic GJD with the cylindrical throat depending on the type of passive stream was determined. Also influence of passive and power fluid on characteristics of GJD work was studied.

Based on high volume of experimental studies results the procedure of GJD calculation for specific technological conditions was created. Moreover the technological schemes of optimization of gaslift wells on the Eastern Area of Orenburg Oil-Gas Condensate Field (EA OOGCF) and reactivation and operation of water-flooded gas wells by using wellhead and downhole GJD were proposed.
After Closure Analysis as an Appraisal Approach
Authors: Usmanova A. , Smith P. , Rylance M.
Published: October 2016

Conventional appraisal consists of drilling, completing and producing a number of wells, with each of these wells being required to establish a production history and sufficient offtake to demonstrate a substantial connected volume. The technique of After Closure Analysis (ACA) offers a complementary or alternative approach to conventional testing, to establish important formation characteristics such as transmissibility (kh//), pore pressure and connected volumes. The principal advantage being that the approach is substantially less time consuming and costly than conventional approaches, particularly in the case of tight formations where substantial enhancement/stimulation may be required in order to establish any sustainable production in the first place.

ACA consists of injecting a fixed volume of fluid above fracturing pressure and at relatively low rates, and then subsequently monitoring the pressure decline response. This approach potentially allows for the calculation of a highly accurate assessment of the transmissibility and combined with formation fluid data the effective kh to this formation fluid. While this technique has been utilised for some time, the application of ACA has been fairly limited in established fields as a reasonably accurate reservoir pressure is required for a meaningful result and therefore depleted environments can present issues. However, in the case of Exploration and Appraisal, formation pressure is typically undisturbed and therefore this approach is well suited and in fact ideal in this case.

The paper will present a series of case histories in a variety of hydrocarbon bearing environments and work the details from the initial concept through demonstration of the results. Additionally, a suite of complimentary pressure transient analyses using conventional approaches will demonstrate the validity of the results. The case histories will clearly demonstrate the relative value that can be achieved by this technique, with direct comparison to conventional approaches. The value of the approach in tighter rock environments will be directly demonstrated. Additionally, a suite of type-curves and selection graphs will be presented that can be used to determine pumping-stage design and decline period requirements. Finally, a suite of lessons learned and operational considerations will be provided in order to maximise the overall efficiency of the approach.

Conventional appraisal approaches require extensive flow-periods and substantial fluid offtake to determine the immediate region of influence/connectivity. The use of ACA offers a supportive and complimentary technique that in combination with a reduced set of conventional test wells offers to augment the datasets available for interpretation at just a fraction of the cost/time of conventional methods. In remote and hard-to-recover areas where such conventional tests can prove inefficient, this technique offers an alternative and complementary means of appraising formations.
Multiphase Inflow Quantification for Horizontal Wells Based on High-Sensitivity Spectral Noise Logging and Temperature Modelling
Authors: Ipatov A. I. , Nemirovitch G. M. , Nikolaev M. N. , Shigapov I. N. , Aslanyan A. M. , Aslanyan I. Y. , Petrova I. A.
Published: October 2016

A pilot project comprising several closely-spaced wells from one pad was carried out in the green East Messoyakha field for further study of properties in this field. The target zone in this field is the oil rim of a highly stratified reservoir containing a gas cap and an aquifer. The field is developed with a system of horizontal wells with horizontal sections up to 1000 m long. Development of such reservoirs always calls for monitoring inflow zones and inflowing fluid composition for timely prevention of gas and water ingress into the wellbore resulting from coning or lateral breakthroughs through the highly permeable zones and for assessment of the reservoir depletion. Horizontal wells in this field are completed with uncemented liners and packers, which makes the task of reservoir flow analysis even more complicated due to the complexity of flow geometry behind the liner.

Accordingly, logging techniques that have a sufficiently deep radius of investigation to be able to collect the required information about the reservoir, such as spectral noise logging (SNL) and high-precision temperature logging (HPT) were used for profiling inflows from the reservoir into the horizontal wellbore section. The SNL tool captures noise signals produced by reservoir fluid flows and has a radius of investigation up to several metres. Such noise signals have a distinctive frequency signature and can be therefore extracted from the entire noise spectrum recorded in the well. Identification of flowing zones using SNL technique is based on this principle. To quantify inflows from the formation, a temperature log analysis is performed using TermoSimTM software system that can simulate thermal processes in the wellbore, surrounding rocks and flow units, and estimate inflow rates by solving the inverse problem. As the survey was conducted in closely-spaced wells, numerical simulations were run with the same subset of input parameters (such as initial temperature distribution etc), which greatly improved the inflow profile reliability.

As a result of the derived inflow profiles analysis, the sources of water encroachment and high gas content in oil during well operation were identified. The inflow profile correlation analysis applied to a group of closely-spaced wells helped to understand the general principles of reservoir-to-wellbore flow geometry in specific geological environment. Data interpretation results were used for planning well interventions with the purpose of improving the performance of production well. The resulting inflow profiles might be incorporated into the field hydrodynamic model to enhance its predictive ability.
Intelligent Control System for Gas-Condensate Field: A Holistic Automated Smart Workflow Approach
Authors: Fomin Vitaliy , Kushmanov Pavel , Purwar Suryansh , Aksenov Mikhail , Durygin Nikolay , Golovin Oleg , Solovyev Iliya , Govorkov Denis , Vedernikova Yuliya , Iskakov Daulet
Published: October 2016

Gas condensate fields present unique challenges regarding data acquisition, data quality, exception-based surveillance, flow modeling, nodal analysis, well testing, allocation, and visualization. Although existing tools and methods address many of these aspects, it is possible to streamline processes and explore increased production efficiency methods. This paper addresses these challenges; it presents a case study of an intelligent control system implementation for a gas-condensate field based on a unified data model, integrated modeling, and cross-domain workflows.

This paper presents a transformative, intelligent, and automated work process, referred to here as "smart workflows." As part of these workflows, virtual gauges are used that are based on inflow models and lifts, adjustable valves, and modular networks. The workflows are implemented on a truly open end-to-end platform that enables the coupling of multiple databases, streamlining of data for an integrated analysis of the measurements and model calculations, and ascertaining the mismatch between the two. The workflows also initialize adaptive self-tuning procedures.

The smart workflows enable engineers to achieve various improvements, including an integrated structure of process data model to enable quick access to validated data, monitoring and control functions to a gas-condensate field in real time, and reduced downtime and operational costs. The smart workflow also supports functions that include collection and verification of measurement data, configuration of the integrated solution component models, evaluation of the action of root causes, and planning of operation scenarios.

As part of the implemented system, an integrated information system data structure sets the degree of relatedness of tasks, each of which can be initialized depending on work situations and/or operator commands.

Such comprehensive analysis of the data provides reliable integrated system configuration parameters of the model, which increases the accuracy of the calculations used in the optimal planning of the operational scenarios.
Modelling of Hydraulic Fractures Propagation in the Layered Elastoplastic Media
Authors: Stefanov Y. P. , Bek D. D. , Akhtyamova A. I. , Myasnikov A. V.
Published: October 2016

One of the understudied problems of hydraulic fracturing are patterns and mechanisms of cracks propagation in the media containing plastic enclaves and layers. The importance of this problem is related to the development of unconventional reservoirs, which may contain a significant amount of clays and kerogen. Apparently, under specific conditions, such formations manifest plastic properties and failure mechanism is of viscous nature and is attended by remarkable plastic deformations. Thus, the question about crack propagation pattern in the layered formations with great contrast in strength and elastoplastic properties is arisen.

Bazhen shale formation could be referred to such unconventional reservoirs. The formation covers an area of almost one million square kilometers and contains about 18 trillion tons of organic matter. The reservoir is built up of interstratification of clay, siliceous and carbonate layers with kerogen, organic matter and other minerals particles, which results in the heterogeneous distribution of mentioned above characteristics of massive.

The goal of this research is the investigation of specific of cracks propagation in the media, containing plastic layers and layers with contrast strength properties. The study was carried out by using the numerical simulation of deformation and failure process of medium with the initial crack of a given length. Calculations were performed using software package where the system of equations of continuum mechanics including equations of motion and consistency and constitutive relations of material behavior were solved numerically. Material behavior is defined in terms of modified Drucker-Prager model with unassociated flaw law.

The emphasis is on the investigation of crack propagation character in the medium with various properties and revealing the conditions under which branching of cracks may occur. As leading factors affecting the cracks propagation character, strength and elastoplastic properties, thickness and relative position of layers and initial stress distribution are considered. Further significant factor defining character of cracks propagation is rate of load application in terms of pressure increasing rate and its changing on the tip of the crack, which as a result determine distribution of pressure in the growing crack