bluuebunny/crossref_metadata_2025_split huggingface dataset:
N-terminal propeptide of type III procollagen for predicting diastolic dysfunction in patients with myocardial infarction and preserved ejection fraction
Authors: Osokina A. V. , Karetnikova V. N. , Polikutina O. M. , Ivanova A. V. , Avramenko O. E. , Gruzdeva O, V. , Barbarash O. L. 
Published: February 2021

Aim. To study changes in the level of fibrotic scarring marker — the N-terminal propeptide type III procollagen (PIIINP) and structural and functional parameters with the assessment of diastolic function in patients a year after ST segment elevation myocardial infarction (STEMI) and preserved left ventricle (LV) contractility.Material and methods. At first, the study included 120 (100%) STEMI patients. Next, patients with an LV ejection fraction (EF) ≥50% were selected. The final analysis included 86 STEMI patients. Upon hospitalization, the patients underwent routine diagnostic tests, coronary angiography with stenting of culprit artery. Echocardiography and determination of venous blood PIIINP and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels was on the 1st (time point 1) and 12th day (time point 2) of disease and after a year (time point 3). To compare the obtained values of fibrotic scarring markers, a control group was formed, including 20 (100%) healthy volunteers, identical in age and sex with the studied sample.Results. On the first day of MI, 25 (29,1%) patients with signs of diastolic dysfunction (DD) were identified among those with preserved LVEF. After 1 year, the number of such patients increased by 10% (n=9). Initially increased (relative to the control group) concentration of PIIINP on the first day (311,2 [220,1; 376,3] ng/ml) decreased by the 12th day (223,3 [195,3; 312,1] ng/ml) and returned to the initial values a year after the MI (312,6 [228,0; 383,8] ng/ml). The NT-proBNP concentration during the hospitalization period did not exceed the reference values and did not differ between 1 and 2 time points (p=0,127). One year later, the NT-proBNP concentration significantly exceeded the values of the previous determinations and amounted to 124,4 pg/ml (p=0,043). According to the ROC analysis, with a PIIINP ≥387,8 ng/ml on the first day, the risk of DD increases (p=0,050, sensitivity, 84,62%, specificity, 55,56%) within a year after STEMI with preserved LVEF.Conclusion. The threshold of PIIINP (≥387,8 ng/ml) was established for the first day of MI, at which the risk of DD increases one year after the index event. An increase in NT-proBNP concentration one year after STEMI indicates the progression of heart failure.
Network-Based Earthquake Magnitude Determination via Deep Learning
Authors: Kuang Wenhuan , Yuan Congcong , Zhang Jie 
Published: February 2021

Abstract
The stability and robustness of determining earthquake magnitude are of great significance in earthquake monitoring and seismic hazard assessment. The routine workflow of determining earthquake local magnitude, such as the widely used Richter magnitude, may result in an unreliable measurement of earthquake magnitude because it relies on individual amplitude measurement of a single station, which is prone to be influenced by natural impulsive noise or anthropogenic noise. In this study, we present an automated estimation of earthquake magnitude by applying a deep-learning algorithm named magnitude neural network (MagNet) based on the full-waveform recordings from a network of seismic stations at China seismic experimental site (CSES). The MagNet consists of a compression component that extracts the global features of waveform data and an expansion component that yields a Gaussian probability distribution representing the magnitude estimation. The MagNet is trained with an augmented data set, which includes 21,700 training samples with evenly distributed magnitudes. From the prediction results on the test data set, the mean errors and standard deviations are −0.017 and 0.21, respectively, for 600 moderate earthquakes with magnitudes ranging from 3 to 5.9, and −0.011 and 0.14, respectively, for 70 small earthquakes with magnitudes ranging from 2.3 to 3.5. However, it remains challenging for large earthquakes (magnitude&gt;6.5), due to the lack of sufficient historical large earthquakes as training data. In addition, testing results show that the new method is capable of minimizing the impact of abnormal noises in the data. These results demonstrate the validity and merits of the proposed deep-learning method in predicting earthquake magnitude automatically.
A histopathological study of urinary bladder neoplasms
Authors: Makwana Seva V , Jhaveri Preeti N , Oza Kishan K , Shah Cherry K 
Published: February 2021

The present study was carried out to describe the Histopathological features of various neoplasms in the urinary bladder biopsies and to categorize the neoplastic lesions according to W.H.O (2016)/ISUP classification of urinary bladder tumors.A total of 37 cases, 28 urinary bladder biopsies (TURBT) and 9 cystectomy specimens of urinary bladder neoplasia [histologically proved] of patients were studied retrospectively over the period from June 2016- Oct 2018 in Pathology department of Smt. N.H.L. medical college. All cases of urothelial carcinomas were graded histologically according to WHO (2016)/ISUP classification.Maximum numbers of patients are in age group 60-69 years. Males (78.37%) are more frequently affected as compared to female. The most frequent Neoplastic findings in Urinary bladder is Invasive Papillary Urothelial carcinoma (81.06%); Low grade (37.8%) being more common than High grade (35.14%). A large percentage (80%) of high grade invasive urothelial cell carcinomas presented with muscle invasion.Invasion to the muscle propria layer correlates with high grade tumor. In 18.5% cases detrusor muscle was absent, hence the importance of including detrusor muscle in the biopsy specimens needs to be emphasized. We must accept the fact that grading is highly subjective and that in future various molecular and immunohistochemical studies will provide better reproducibility.
Spectrum of lesions of head and neck in a medical college of North India
Authors: Kumar Nikhilesh , Sharma Honey Bhasker , Bansal Megha , Gupta Monika 
Published: February 2021

Head and neck lesions especially oral cancers and pre-cancerous lesions have a high prevalence in India, especially in states like Uttar Pradesh pertaining to use of Pan masala, smokeless tobacco and zarda in the population. The lesions are common in patients of all age groups.This histopathology based study was conducted for the assessment of neoplastic and non-neoplastic lesions of head and neck in the region around North Indian city of Lucknow.This is a retrospective study conducted in the Department of Pathology, T S Misra Medical college and Hospital, Amausi, Lucknow. The head and neck cases for time period of two years and eight months were retrieved from the histopathologic section of department. Thorough analysis of these specimens was done and data was compiled based on histomorphological diagnosis and other parameters like site of lesion, sex and age group.Study was done for 189 biopsies from head and neck region. Peak incidence of case was seen in 21-50 years age group, in the overall age range 3 to 86 years of our study. Male outnumbered female by ratio of 1.77:1. 63 cases of the study were inflammatory, 40 cystic, 46 benign, 14 dysplastic and rest 26 cases were malignant. Commonest malignant lesion was Squamous cell carcinoma of the oral cavity.It was noteworthy that precancerous and malignant lesions of oral cavity constitute a high percentage of head and neck lesions for the present cohort of referral patients.
Exfoliative cytology of different body fluids- an important aid to primary diagnosis
Authors: Thakur Ajay Singh , Tiwari Avani , Chandrakar Pradeep , Choraria Amit , Choudhary Vivek 
Published: February 2021

Cytological examination of exfoliated cells in various effusion fluids is very challenging and of paramount importance for early diagnosis and management of various pathological processes. It is of utmost significance in identifying malignant cells and hence throws light on the cause, staging and prognosis of cancer. This study was carried out to know the different trends of various types of effusions for various pathological processes with an emphasis on malignant effusion in a tertiary care centre. Retrospective, analytical, observational study done over a period of one year from January 2019 to December 2019. A total of 418 cases including peritoneal and pleural and cerebrospinal fluid and urine were analyzed. Samples were centrifuged for five minutes at 2000 rpm and smears prepared from deposit were stained by Papanicolaou (PAP) and May-Grunwald- Giemsa (MGG) stains. Out of 418, 221 were peritoneal effusions, 172 were pleural, 20 cerebrospinal fluids and 5 urine. Out of 221 cases of peritoneal effusions, 144 were non neoplastic and 61 were malignant effusion. Out of total 172 pleural effusions 139 were non neoplastic and 27 neoplastic. Commonest malignancy in peritoneal and pleural fluid was adenocarcinoma from ovary and lung respectively. Cytological evaluation of various fluids is simple, rapid, inexpensive and less invasive tool with high accuracy and thereby reducing the need for invasive investigations. It is especially helpful in evaluating and staging malignancies thereby guiding the clinician in further management.
Real Time Borehole Stability Monitoring and Pre-drill Model Calibration using LWD Sonic — A Case Highlight.
Authors: Weaver Sophia , Xiao Xiaohui , Vines Rob 
Published: February 2021

Abstract
Borehole instability challenges can account for a significant percentage of non-productive time and associated costs in drilling. This is even more so in deepwater subsea wells due to high development costs coupled with the subsurface complexities associated with turbidite reservoirs. Pre-drill borehole stability studies in this field case were performed by evaluating offset well history and geophysical log data and calibrating these against direct well measurements and drilling experiences, with the objective of recommending the appropriate mud weight. However, the validation of the pre-drill borehole stability model derived from sonic data taken in the only offset well in the field was deemed necessary for effective borehole stability monitoring in this case. Additionally, the inability to run wireline in a highly deviated well fuelled the need for acoustic data acquisition using logging-while-drilling (LWD). Sonic data was acquired by LWD (a first in the field) and this aided mud weight optimization to successfully drill the well to TD without any borehole stability problems. This paper describes the application of this solution to managing well delivery uncertainties in a deepwater field and highlights the process, results and lessons from the event to aid future applications.
New Viewpoint on the Geology and Hydrocarbon Prospectivity of the Seychelles Plateau
Authors: Granath James , Rango Rolf , Emmet Pete , Ford Colin , Lambert Robert , Kasli Michael 
Published: February 2021

ABSTRACT
We have reprocessed, re-imaged, and interpreted 10000+ km of legacy 2D seismic data in the Seychelles, particularly in the western part of the Plateau. Seychelles data have been difficult to image, particularly for the Mesozoic section: volcanics are a major attenuator of low frequency signal, and a hard water bottom contributes to signal problems. Enhanced low frequency techniques were applied to improve the signal fidelity in the 4 to 20 Hz range, and to remove spectral notches of shallow geologic origin. These efforts have allowed a reasonable view of the structure of the Plateau to a depth equivalent to about 3.5 sec TWT, and permit a comparison of areas atop the Plateau to the south coast where the three 1980's Amoco wells were drilled. It is clear that the main Plateau area of the Seychelles (excluding the outlying territories) is comprised of several separate basins, each with similar Karoo, Cretaceous, and Cenozoic sections that relate to the East African and West Indian conjugate margins, but the basins each have nuanced tectono-stratigraphic histories. The previously recognized Correira Basin in the SE and the East and West South Coast Basins face the African conjugate margin; other unimaged ones complete the periphery of the Plateau. The interior of the Plateau is dominated by the Silhouette Basin to the west of the main islands and the Mahé Basin to the east. The co astal basins have harsh tectono-thermal histories comparable to other continental margins around the world; they are typically characterized by stretching, subsidence and breakaway from their respective conjugate margins. In contrast the interior basins are comparable to ‘failed’ rift systems such as the North Sea or the Gulf of Suez. The South Coastal Basins, for example, tend to be more extended which complicated interpretation of the Amoco wells, but they have significant upside, as exemplified by the Beau Vallon structure. The interior basins, on the other hand, have typically simpler structure: the Silhouette Basin contains a system of NW-trending linked normal faults that could easily harbor North Sea-sized hydrocarbon traps with a variety of rift-related reservoir possibilities. Bright, reflective, hard volcanic horizons are less common than usually presumed, but most of the basins may contain considerable pyroclastic material in parts of the section. All of the basins appear to be predominantly oil prone, with considerable upside prospectivity.
Barik Reservoir Description- An Evolving Concept
Authors: Rashdi Khalil Al , Spain David 
Published: February 2021

Abstract
Khazzan field, situated in Block 61 in northern Oman, contains hydrocarbons at several deep levels, including the Barik, Miqrat, Amin and Buah formations. The Barik and Amin reservoirs are being developed in the southern portion of the block to produce 1 bcf/d of gas by end 2017. The development, jointly owned by Oman Oil Company (40%) and BP (60% and operator), will cost over 16 billion US$ and will include a central processing facility and surface facilities for about 300 wells. Most of the wells will be 1000m long horizontal wells, completed using multiple hydraulic fracturing techniques. The two other reservoirs, Miqrat and Buah, contain high H2S levels; these will not be developed at this phase due to high subsurface uncertainties and the cost to process the sour development.
This paper presents a case study of an evolving reservoir description of a large, tight gas reservoir, the Barik Formation. It is rare to embark on a major “greenfield” reservoir development of a tight gas reservoir with limited static and almost no dynamic data. The reservoir description is essential to the successful evaluation and management of the inherent subsurface uncertainty at this stage in the field development. Building an associated appraisal plan and being flexible to new understanding is required to make the development a success. The reservoir description is guiding the ongoing appraisal activities in an attempt to reduce the risk and increase the overall project value.
This paper presents the evolution of the reservoir description over the last 6 years of BP activity in Block 61 in the Sultanate of Oman. It reviews three stages of reservoir description: Pre-Appraisal, Mid-Appraisal, and Development. The pre-appraisal description was built using the pre-bid data package and published literature to support the commercial access decisions. The Mid Appraisal description provided a health-check for development readiness and appraisal plan revision. Finally, the Development description is presented in a 3D geo-cellular model which is based on the summary of the appraisal activities and supporting field development learnings. The paper discusses these descriptions and the benefits of the changing description, explanation of the advantages of front end loading at the early appraisal stage and how this has led us to our current state
Multistage Horizontal Well Hydraulic Fracturing Stimulation Using Coiled Tubing to Produce Marginal Reserves from Brownfield: Case Histories and Lessons Learned
Authors: Hassan Amro , ElMeguid Ahmed Abd , Waheed Arshad , Salah Mohamed , ElKarim Essam Abd 
Published: February 2021

Abstract
The Baharyia formation is a common reservoir in the Western Desert of Egypt. It is characterized as a heterogeneous reservoir with low sand quality. It is comprised of fine-grained sandstone, thin, laminated, sand-poor parasequences with shale interbeds. The heterogeneity and low permeability of the Upper Baharyia reservoirs are the primary challenges to maintaining economic well productivity.
The interest in developing low permeability reservoirs stems from favorable economics attributed to advancements in horizontal well drilling and hydraulic fracturing technology, offering methods to increase production by increasing the contact area of the producing interval. Subsequently, it became apparent that wellbore contact alone was not always sufficient for providing production increases expected, thus requiring multistage hydraulic fracturing (MSHF) stimulation treatments to achieve production targets.
Primary well production analysis revealed that the cumulative production from the horizontal well discussed was enhanced from 37 to 70% of recoverable reserve and the recovery factor was doubled. From a production analogy standpoint, these resulted in reduced drilling of three vertical wells and had direct economic benefits by reducing the installed artificial lift strings, related expensive artificial lift equipment repairs, and the number of necessary workovers.
This paper takes a multidisciplinary approach to help understand productivity enhancement of low permeability reservoirs in the Western Desert of Egypt, through a detailed analysis of well performance and successful implementation of MSHF in horizontal wells to maximize drainage volume around the well. It is intended to serve as guidelines to help operators facing similar challenges.
Achieving Cementing Improvement in Horizontal Tight Gas Field Development
Authors: Ariyanto Pungki , Najwani Mohamed A. , Najwani Yaseen , Al Lawati Hani , Pfeiffer Jochen , Al Abri Muna 
Published: February 2021

Abstract
This paper outlines how a drilling team is meeting the challenge of cementing a production liner in deep horizontal drain sections in a tight sandstone reservoir. It is intended to show how the application of existing technologies and processes is leading to performance gain and improvements in cementing quality.
The full field development plan of the tight reservoir gas project in the Sultanate of Oman is based on drilling around 300 wells targeting gas producing horizons at measured depths of around 6,000m MD with 1,000m horizontal sections.
Effective cement placement for zonal isolation is critical across the production liner in order to contain fracture propagation in the correct zone. The first few attempts to cement the production liner in these wells had to overcome many challenges before finally achieving the well objectives. By looking at the complete system, rather than just the design of the cement slurry, the following criteria areas were identified:
- Slurry design
- Mud removal and cement slurry placement
- Liner hanger and float equipment
Improvements have been made in each of these areas, and the result has been delivery of a successfully optimised liner cementing design for all future horizontal wells.
Petrophysical and Fluid Flow Properties of a Tight Carbonate Source Rock Using Digital Rock Physics
Authors: Dernaika Moustafa , Jallad Osama Al , Koronfol Safouh , Suhrer Michael , Teh Woan Jing , Walls Joel , Matar Saad , Murthy Natarajan , Zekraoui Mohammed 
Published: February 2021

Abstract
The evaluation of shale is complicated by the structurally heterogeneous nature of fine-grained strata and their intricate pore networks, which are interdependent on many geologic factors including total organic carbon (TOC) content, mineralogy, maturity and grain-size. The ultra-low permeability of the shale rock requires massive hydraulic fracturing to enhance connectivity and increase permeability for the flow. To design an effective fracturing technique, it is necessary to have a good understanding of the reservoir characteristics and fluid flow properties at multiple scales.
In this work, representative core plug samples from a tight carbonate source rock in the Middle East were characterized at the core- and pore-scale levels using a Digital Rock Physics (DRP) workflow. The tight nature of the carbonate rocks prevented the use of conventional methods in measuring special core analysis (SCAL) data. Two-dimensional Scanning Electron Microscopy (SEM) and three-dimensional Focused Ion Beam (FIB)-SEM analysis were studied to characterize the organic matter content in the samples together with (organic and inorganic) porosity and matrix permeability. The FIB-SEM images in 3D were also used to determine petrophysical and fluid flow (SCAL) properties in primary drainage and imbibition modes.
A clear trend was observed between porosity and permeability related to identified rock fabrics and organic matter in the core. The organic matter was found to have an effect on the imbibition two-phase flow relative permeability and capillary pressure behavior and hysteresis trends among the analyzed samples. The data obtained from DRP provided information that can enhance the understanding of the pore systems and fluid flow properties in tight formations, which cannot be derived accurately using conventional methods.
$40 Billion Learning Curve: Leveraging Lessons Learned to Minimize the Overall Investment in Unconventional Plays
Authors: Fredd C.N.. N. , Daniels J.L.. L. , Baihly J.D.. D. 
Published: February 2021

AbstractThe industry has made significant advances in the way we exploit unconventional resources such as source rock and tight reservoirs. Innovations in horizontal drilling and multistage fracturing have unlocked previously uneconomical plays, and technology has brought a step change in operational efficiency. Lessons learned from unconventional resources highlight collaboration and integrated reservoir-centric workflows as common traits for economic success.The development of unconventional resources in North America was aided by the readily available infrastructure, water resources, expertise, and a general understanding of potential sweet spots due to numerous well penetrations. Even with these favorable conditions, an estimated 40% of unconventional wells are uneconomical due to spatial variability in reservoir characteristics, lateral heterogeneity along the wellbores, accuracy of well placement, and variability in drilling, completion, and stimulation practices. This non-ideal economic performance also ineffectively consumes local resources such as water and proppant.This paper provides a retrospective assessment of the Barnett Shale and Eagle Ford Shale to highlight lessons learned and the associated value of those learnings. The impact of applying technology and utilizing a data-driven approach based on measurements will be assessed in terms of the investment required to achieve a given hydrocarbon production. The results indicate that these unconventional plays could have been developed with well counts reduced by the thousands, water consumption reduced by billions of gallons, and investment savings in the billions of dollars if initially exploited by applying the key lessons learned from over the past 30 years. This potential reduction in investment amounts to $40 billion for the Barnett Shale (shale gas) plus the Eagle Ford Shale (oil window) and represents the significant value of moving along the learning curve. Fortunately, there is no need to repeat this learning curve investment, as key lessons learned can be applied to other unconventional plays around the world. This learning curve is of specific value in international plays where local infrastructure, supply, and market conditions may not be as favorable as in North America, hence necessitating a different approach to optimize the overall investment when developing unconventional plays.