bluuebunny/crossref_metadata_2025_split huggingface dataset:
Integrated Hydraulic Fracture Geometry Evaluation Based on Pre-Cambrian Tight Silicylate Reservoir in South Oman Salt Basin
Authors: Smirnov Dmitrii , Isaee Omar AL , Moiseenkov Alexey , Al Hadhrami Abdullah , Shabibi Hilal , Kaabi Saqer , Sayapov Ernest 
Published: January 2022

Abstract
Pre-Cambrian South Oman tight silicilyte reservoirs are very challenging for the development due to poor permeability less than 0.1 mD and laminated texture. Successful hydraulic fracturing is a key for the long commercial production. One of the main parameter for frac planning and optimization is fracture geometry. The objective of this study was summarizing results comparison from different logging methods and recommended best practices for logging program targeting fracture geometry evaluation.
The novel method in the region for hydraulic fracture height and orientation evaluation is cross-dipole cased hole acoustic logging. The method allows to evaluate fracture geometry based on the acoustic anisotropy changes after frac operations in the near wellbore area. The memory sonic log combined with the Gyro was acquired before and after frac operations in the cased hole. The acoustic data was compared with Spectral Noise log, Chemical and Radioactive tracers, Production Logging and pre-frac model. Extensive logging program allow to complete integrated evaluation, define methods limitations and advantages, summarize best practices and optimum logging program for the future wells.
The challenges in combining memory cross-dipole sonic log and gyro in cased hole were effectively resolved. The acoustic anisotropy analysis successfully confirms stresses and predominant hydraulic fractures orientation. Fracture height was confirmed based on results from different logging methods. Tracers are well known method for the fracture height evaluation after hydraulic frac operations. The Spectral Noise log is perfect tool to evaluate hydraulically active fracture height in the near wellbore area. The combination of cased hole acoustic and noise logging methods is a powerful complex for hydraulic fracture geometry evaluation. The main limitations and challenges for sonic log are cement bond quality and hole conditions after frac operations. Noise log has limited depth of investigation. However, in combination with production and temperature logging provides reliable fit for purpose capabilities.
The abilities of sonic anisotropy analysis for fracture height and hydraulic fracture orientation were confirmed. The optimum logging program for fracture geometry evaluation was defined and recommended for replication in projects were fracture geometry evaluation is required for hydraulic fracturing optimization.
Improved Efficiency and Reliability of Hydraulic Fracture Modeling and Design with Standardized Stress Inputs for South Oil Fields in Sultanate of Oman
Authors: Al Zadjali Ruqaiya , Mahaja Sandeep , M. Molenaar Mathieu 
Published: January 2022

Abstract
Hydraulic Fracturing (HF) is widely used in PDO in low permeability tight gas formations to enhance production. The application of HF has been expanded to the Oil South as conventional practice in enhancing the recovery and production at lower cost.
HF stimulation is used in a number of prospects in the south Oman, targeting sandstone formations such as Gharif, Al Khlata, Karim and Khaleel, most of which have undergone depletion.
Fracture dimension are influenced by a combination of operational, well design and subsurface parameters such as injected fluid properties, injection rate, well inclination and azimuth, rock mechanical properties, formation stresses (i.e. fracture pressures) etc. Accurate fracture pressure estimate in HF design and modeling improves reliability of HF placement, which is the key for improved production performance of HF. HF treatments in the studied fields provide large volumes of valuable data.
Developing standardized tables and charts can streamline the process to generate input parameters for HF modeling and design in an efficient and consistent manner. Results of the study can assist with developing guidelines and workflow and for HF operations.
Field HF data from more than 100 wells in south Oman fields were analyzed to derive the magnitude of breakdown pressure (BP), Fracture Breakdown Pressure (FBP), Instantaneous Shut-In Pressure (ISIP) pressure, and Fracture Closure Pressure (FCP) and develop input correlations for HF design. Estimated initial FCP (in-situ pore pressure conditions) is in the range of 15.6 - 16 kPa/mTVD at reservoir formation pressure gradient of about 10.8 kPa/m TVD bdf. However, most of the fields have undergone variable degree of depletion prior to the HF operation. Horizontal stresses in the reservoir decrease with depletion, it is therefore important to assess the reduction of FCP with reduction in pore pressure (stress depletion). Depletion stress path coefficient (i.e. change on FCP as a fraction of change in pore pressure) was derived based on historic field data and used to predict reduction of FCP as a function of future depletion. Data from this field indicates that the magnitude of decrease in fracture pressure is about 50% of the pore pressure change.
Based on the data analysis of available HF data, standardized charts and tables were developed to estimate FCP, FBP, and ISIP values. Ratios of FBP and ISIP to FCP were computed to establish trend with depth to provide inputs to HF planning and design. Results indicate FBP/FCP ratio ranges between 1.24-1.35 and ISIP/FCP ratio ranges between 1.1 to 1.2.
Developed workflow and standardized tables, charts and trends provide reliable predictions inputs for HF modeling and design. Incorporating these data can be leveraged to optimize parameters for HF design and modeling for future wells.
4D Geomechanical Research for Fracturing Optimization of Low-Permeability Reservoir
Authors: Zheng Sheng , Zhou Wei , Wang Xiaoguang , Chen Liang , Xie Dan , Cheng Hongjie , Lian Liming , Jiang Zhibin , Qu Huailin , Qu Liming , Qi Lisha , Yang Xiao 
Published: January 2022

Abstract
China has abundant low-permeability oil and gas resources. A lot of practice has proved that low-permeability reservoirs must undergo hydraulic fracturing to obtain commercial production capacity. Geomechanical characteristics are the key factor for fracturing. It plays a very important role in the oil field exploration and production. It is not only the driving force for oil and gas migration, but also provides a basis for wellbore stability analysis and drilling optimization design. The state of the formation stress field and the mechanical properties of the rock jointly determine the direction, shape and orientation of the fracture extension of the fracturing. Together it affects the stimulation effect of fracturing. Realizing the high-efficiency development of low-permeability reservoirs is a key and difficult problem facing for oil filed operator. Horizontal wells drilling and hydraulic fracturing are the core technology for increasing single well production in low-permeability reservoirs. The effectiveness of reservoir reconstruction directly determines the production capacity of the reservoir. In order to clarify the influence of static and dynamic geomechanics on the scale of reservoir stimulation in the process of horizontal well fracturing, and ultimately provide effective technical support for the formulation and optimization of reservoir stimulation design. This study is based on the study of single well one-dimensional geomechanics, using the structural characteristics and seismic attributes of low-permeability reservoirs to study the characteristics of the three-dimensional spatial distribution of mechanics. On this basis, combined with real-time fracturing treatment data and micro-seismic monitoring data, dynamic (four-dimensional) stress field simulations are continuously carried out. The research results can be mainly used to guide the optimization of reservoir stimulation and the evaluation of filed development plan.
No Need for Radio Active Tracer When Mother Nature Helps Detecting the Effective Hydraulic Fracture Height
Authors: Lukmanov Rinat , Jabri Said , Ibrahim Ehab 
Published: January 2022

Abstract
The tight gas reservoirs of Haima Supergroup provide the majority of gas production in the Sultanate of Oman. The paper discusses a possibility of using the anomalies from natural radioactivity to evaluate the fracture height for complex tight gas in mature fields of Oman.
The standard industry practice is adding radioactive isotopes to the proppant. Spectral Gamma Ray log is used to determine near wellbore traced proppant placement. Spectral Noise log in combination with Production logs helps to identify the active fractures contributing to production. These methods complement each other, but they are obviously associated with costs. Hence, majority of wells are fracced without tracers or any other fracture height diagnostics. However, in several brown fields, an alternative approach to identify fracture height has been developed which provides fit-for-purpose results. It is based on the analysis of naturally occurring radioactive minerals (NORM) precipitation. The anomalies were observed in the many gas reservoirs even in cases when tracers were not used. At certain conditions, these anomalies can be used to characterize fracture propagation and optimize future wells hydraulic Fracture design.
A high number of PLTs and well test information were analyzed. Since tight formations normally don't produce without fracturing, radioactive anomalies flag the contributing intervals and hence fracture propagation. The main element of analysis procedure is related to that fact that if no tracers applied, the discrepancy between normalized Open Hole Gamma Ray and Gamma Ray taken during PLT after 6-12 months of production can be used instead to establish fracture height. This method cannot be applied for immediate interpretation of fracture propagation because time is required to precipitate NORM and using the anomalies concept. The advantage of this method is that it can be used in some fields to estimate the frac effectiveness of wells without artificial tracers.
It is normally assumed that the Natural radioactivity anomalies appear mainly due to co-production of the formation water. However, in the fields of interest the anomalies appear in wells producing only gas and condensate. This observation provides an opportunity for active fracture height determination at minimum cost.
Transcriptome Analysis of Cultivated and Wild Ginseng in Different Growth Years Revealed the Regulatory Mechanism of Ginsenosides
Authors: Fang Xiaoxue , Wang Manqi , Zhou Xinteng , Wang Huan , Wang Huaying , Xiao Hongxing 
Published: January 2022

Abstract
Background: As a famous Chinese medicine, ginseng has been used in the world for nearly 5,000 years. Wild ginseng is endangered due to environmental damage. Thus, cultivated ginseng is developed to replace wild ginseng. The morphological and physiological characteristics of both wild ginseng and cultivated ginseng change during growth, and the mechanism of this change is not yet understood. Results: This study performed transcriptome sequencing on the roots, stems and leaves of cultivated ginseng and wild ginseng with different growth years, exploring the effect of growth years on gene expression in ginseng. The number of DEGs in cultivated ginseng is more than that in wild ginseng. Based on the weighted gene co-expression network analysis, we found that the growth years significantly affected the gene expression of MAPK signaling pathway - plant and terpenoid backbone biosynthesis pathway in cultivated ginseng, but had no effects in wild ginseng. Furthermore, the growth years had significant effects on the genes related to ginsenoside synthesis in cultivated ginseng, and the effects were different in the roots, stems and leaves. However, it had little influence on the expression of genes related to ginsenoside synthesis in wild ginseng and no effect on leaves. These results showed wild ginseng was less affected by growth years than cultivated ginseng. Furthermore, HMGR, SS, DXS, DS, IspF, AACT, CYP450 and UGTs were related with MYB, NAC, AP2/ERF, bHLH and WRKY transcription factors. Growth years may regulate genes for ginsenoside synthesis by influencing these transcription factors, thereby affecting the content of ginsenosides. Conclusions: This study complemented the gaps in the genetic information of wild ginseng in different growth periods and different tissues and provided a new insight into the mechanism of ginsenoside regulation.
Hydrochemical and Stable Isotope Analyses Show Limited Interactions Between Groundwater and Lake Water in the Lake Bosomtwi Impact Crater, Ghana.
Authors: Loh Yvonne Sena Akosua , Fynn Obed Fiifi , Manu Evans , Afrifa George Yamoah , Addai Millicent Obeng , Akurugu Bismark Awinbire , Yidana Sandow Mark 
Published: January 2022

Abstract
The relationship between groundwater and surface water in the Lake Bosumtwi impact crater has been assessed using hydrochemical data and stable water isotopes of δ18O and δD. This study aimed to define likely groundwater flow and recharge zones, estimate the rate of evaporation, and examine the relationship between the lake and groundwater in the study area. The results of Q-Mode hierarchical cluster analysis (HCA) clearly differentiate the lake water from the groundwater based on their spatial relationship. These preliminary results indicated that groundwater recharge occurs on the hilltops of the crater, where it is slightly acidic with low levels of dissolved minerals, characterized by short residence time and rapid unrestricted vertical infiltration and recharge. The groundwater becomes more mineralized with longer contact times and deeper circulation with the host rock, while it flows from the recharge areas towards the lake at lower elevations. Analyses of stable water isotopes of δ18O and δD showed a high evaporation rate on the lake surface, of ~90% with a relatively significant evaporative enrichment, whereas groundwater showed a relatively lower evaporation rate ranging between 54-60%. Both reservoirs do not appear to be hydraulically connected, and where such a connection exists, it is expected to favour the lake.
Total Hip Arthroplasty: Psychometric Validation of the Italian Version of Forgotten Joint Score (FJS-12)
Authors: Longo Umile Giuseppe , Salvatore Giuseppe , De Salvatore Sergio , Santamaria Giulia , Indiveri Anna , Piergentili Ilaria , De Marinis Maria Grazia , Denaro Vincenzo 
Published: January 2022

Abstract
Background: Patient’s satisfaction after surgery was traditionally assessed by pre, and post-surgical scores and Patient-Reported Outcome Measures (PROMs) scales. Patients treated by Total hip arthroplasty (THA) usually perform well; therefore, it is useful to have a PROMs’ scale with a low ceiling effect as the Forgotten Joint Score-12 (FJS-12). PROMs have to be validated in the local language to be used. This study aims to perform a psychometric validation of the Italian version of FJS-12 in a group of consecutive patients treated by THA.Methods: Each patient completed both the Italian version of FJS-12 and Western Ontario and McMaster University Osteoarthritis Index (WOMAC) in preoperative evaluation, after two weeks and 1 month, 3 months and 6 months postoperative follow-up. The reliability, internal consistency, test-retest reliability, and measurement error were evaluated.Results: 53 patients were included. Cronbach’s α between 0.6 and 0.9 indicated good internal consistency for the FJS-12. The test-retest reliability was acceptable. The Pearson correlation coefficient between the FJS-12 and WOMAC was 0.238 (P=0.087) at baseline, r = 0.637 (P < 0.001) at 1 month, r = 0.490 (P < 0.001) at 3 months and r = 0.572 (P < 0.001) at 6 months. The ceiling effect was above the acceptable range (15%) for FJS-12 in 1 month (26.4%) and WOMAC in 6 months follow-up (24.5%).Conclusions: An excellent test-retest reliability, a good internal consistency, and a good validity by medium-high correlation with the WOMAC were assessed for FJS-12. However, the responsiveness for the FJS-12 score was not assessed.
Shared Manufacturing in A Differentiated Duopoly with Capacity Constraints
Authors: Chen Junlong , Sun Chaoqun , Liu Jiali 
Published: January 2022

Abstract
This study sets up a differentiated duopoly model considering capacity constraints and shared manufacturing, investigates the equilibrium results, examines the effects of product differentiation and capacity constraints in three scenarios, and compares the equilibrium outcomes in three cases under Cournot and Stackelberg competition. We find that capacity constraints affect the relationships among product differentiation, equilibrium results, and the market share of enterprises. Shared manufacturing impacts the degree of excess capacity, profits, consumer surplus, and social welfare; however, it may sometimes play a negative role in alleviating excess capacity. Moreover, Cournot competition is a better choice for enterprises with capacity constraints compared to Stackelberg competition.
Self-controlled Sequencing Suggests that Somatic Mutations of Signaling, Transcription and Tumor Suppression Genes are a Precondition for AML Transformation in MDS
Authors: Xu Feng , Wu Ling-Yun , Guo Juan , He Qi , Zhang Zheng , Li Xiao 
Published: January 2022

Abstract
Background
The transformation biology of secondary AML from MDS is still not fully understood. Here, we performed a large cohort of paired self-controlled sequences including target, whole-exome and single cell sequencing to search AML transformation-related mutations (TRMs).
Methods
39 target genes from paired samples from 72 patients with MDS who had undergone AML transformation were analyzed by next generation target sequencing. Whole exome and single-cell RNA sequencing were used to verify the dynamics of transformation.
Results
The target sequencing results showed that sixty-four out of the 72 (88.9%) patients presented presumptive TRMs involving activated signaling, transcription factors, or tumor suppressors. Of the 64 patients, most of TRMs (62.5%, 40 cases) emerged at the leukemia transformation point. All three of the remaining eight patients analyzed by paired whole exome sequencing showed TRMs which are not included in the reference targets. No patient with MDS developed into AML only by acquiring mutations involved in epigenetic modulation or RNA splicing. Single-cell sequencing in one pair sample indicated that the activated cell signaling route was related to TRMs which take place prior to phenotypic development. Of note, target sequencing defined TRMs were limited to a small set of seven genes (in the order: NRAS/KRAS, CEBPA, TP53, FLT3, CBL, PTPN11 and RUNX1, accounted for nearly 90.0% of the TRMs).
Conclusions
Somatic mutations involving in signaling, transcription factors, or tumor suppressors appeared to be a precondition for AML transformation from MDS. The TRMs may be considered as new therapy targets.
Effect of Neoadjuvant Iodine-125 Brachytherapy Upon Resection of Glioma
Authors: Wang Congxiao , Liu Chao , Jiang Han , Zhang Wei , Yang Lili , Li Xueda , Li Zixiang , Peng Lijing , Hu Xiaokun , Sun Peng 
Published: January 2022

Abstract
Background: A more extensive surgical resection of glioma contributes to improved overall survival (OS) and progression-free survival (PFS). However, some of the patients lost the chance of surgical resection when the tumor involves critical structures. Purpose: The present study aimed to assess the feasibility of neoadjuvant 125I brachytherapy followed by total gross resection for initially inoperable glioma.Methods:Six patients diagnosed with inoperable glioma due to invasion of eloquent areas, bi-hemispheric diffusion, or large tumor volume received 125I brachytherapy. Surgical resection was performed when the tumor shrank, allowing a safe resection, assessed by the neurosurgeons. Patients were followed up after surgery.Results:Tumor shrinkage after adjuvant 125I brachytherapy enabled a total gross resection of all six patients. Four patients were still alive at the last follow-up, with the longest survival time of more than 50 months, two of which returned to a normal life with the KPS of 100. Another two patients got a neurological injury with the KPS of 80 and 50, respectively. One patient with grade Ⅱ glioma died 34 months, and another patient with grade Ⅳ glioma died 40 months later after the combined therapy.Conclusions: In the present study, the results demonstrated that 125I brachytherapy enabled a complete resection of patients with initially unresectable gliomas. 125I brachytherapy may offer a proper neoadjuvant therapy method for glioma.
Mineralogy and physic-chemical characteristics of indurated shale quarry waste and influence of firing temperature on their ceramic properties for incorporation in production of roofing tile
Authors: Nweke Obisi Matthias , Omeokachie Adolphus I , Okogbue Celestine O , Eze Hilary N 
Published: January 2022

Abstract
Quarry wastes from indurated shales with huge reserves across Abakaliki, Southeastern Nigeria were evaluated for use as raw materials in manufacturing of roofing tile. Firstly, the indurated shales were investigated by their mineralogical (X-ray diffraction, XRD), chemical (X-ray fluorescence) and physical (grain size distribution and Atterberg limits) characteristics. As technologies of building-related ceramic production involved firing to varying temperatures, ISQW samples were fired to determine their technological properties (linear shrinkage, weight loss, water absorption, bulk density and flexural strength). From the results, ISQWs composed predominately of fine particles (clayey-silt) with medium plasticity. The XRD revealed predominance of illite-chlorite-vermiculite with high contents of quartz and variable percentage of carbonate and feldspar. The oxides were dominated by SiO2 and Al2O3, low contents of ferromagnesian elements with considerable amounts of alkali (K2O and Na2O) which can act as fluxes and may have effect during sintering. The CaO concentrations are variable and relate to carbonate contents. Characterizations based on compositional ternary, clay workability chart and Winkler diagrams revealed their acceptable level for ceramic applications. The Winkler and McNally diagrams revealed heterogeneous behaviors as the samples fell within vertical corrugated bricks, perforated products and tiles production. The ISQWs fired at 1000oC revealed considerable weight loss, linear shrinkage and water absorption with unsatisfactory performance for flexural strength. Flexural strength increased as firing temperature increased due to the formation of dense phase. Beneficiation of ISQWs in order to achieve excellent properties and reduce sintering temperature for their usability in production of roofing tiles is recommended.