bluuebunny/crossref_metadata_2025 huggingface dataset:
From Zoo to Social Media: The Evolution of Human-Captive Wildlife Relations
Authors: Lenzi Christian , Speiran Siobhan , Grasso Chiara
Published: February 2021

In the twenty-first century– an era of increasing domestic and international tourism- there are boundless opportunities to encounter wild animals both in their home countries and ex situ in zoological facilities around the world. Tourism activity– especially at accredited zoos and sanctuaries –plays a crucial role in the conservation of wild animal populations, and influences the welfare of individuals within involved species. Unfortunately, not all zoos and sanctuaries prioritize the conservation and welfare of their animals, such as those who promote irresponsible and mutually-harmful visitor-animal encounters for economic profit. While the relationship between visitors and animals at zoological facilities has shifted over time to match evolving morals and sentiments towards animals, there is still a storied tendency of visitors preferring close encounters with charismatic wild species. Since the 1970s, researchers’ attention has increasingly focused on assessing the influence of the visitor effect, which refers to the impact that viewing, touching, feeding, holding, and riding captive wildlife has on the animals. Many wildlife attractions promote such encounters, despite research suggesting that close interactions with visitors can cause stress and harm to involved species. Such activities are further promoted through the “selfie tourism” phenomenon, in which visitors capture images of themselves in too-close proximity to wild animals to be shared on social media. In this commentary, we consider the challenge of “selfie tourism”, and how it can promote unethical relationships between humans and wildlife and lead to deleterious implications for the animals’ conservation and welfare.
The Learning Process in The Classroom Through the Mind Mapping Approach from The Philosophy of Progressivism
Authors: Fredrik Jonathan , Wibowo Bagus Ardi
Published: February 2021

Education plays a role in human life to prevent people from poverty, underdevelopment, and ignorance so that it is necessary to change the way of thinking of humans themselves to overcome these problems. The progress of the human mindset is a form of change and cannot be separated from the achievement of creativity. This article aims to describe and explain the use of mind maps in mathematics learning from a progressivism point of view through the learning process carried out from the primary and secondary education levels to produce creative products that can help students improve learning achievement through the role of the teacher as a facilitator and students as a learning center. This article uses literature study method, data is collected and analyzed as secondary data including books, journals and proceedings relevant to the topic. The results showed that the mind map method could be used by teachers and students to change the concept of thinking through active student involvement through the making of mathematics learning materials, addition and building space and the area of a circle in an attractive graphic form. Progressivism views that progress in thinking is a process of change and through the mindmaping learning method the concept of subject matter can be visualized in the form of a graphic infrastructure that can stimulate the right and left brains so that it can be useful to free students from the snare of rules when starting to learn. The conclusion of this study is a change in mindset that is in line with the viewpoint of progressivism philosophy is through a mind map learning model that can produce student creativity products and the role of the teacher as a facilitator can occur.
Students’ Mathematical Communication Skills Based on Keirseys’ Personality Types of Idealist and Gender
Authors: Mulyastuti Indah Dwi , Budiyono Budiyono , Indriati Diari
Published: February 2021

Learning in the 21st century can be defined as learning that provides 21st century skills, one of which is communication. Mathematics learning allows students to communicate mathematical ideas clearly. Different personality types can affect the way they communicate, and other activities in learning mathematics. This study aims to describe students' mathematical communication skills in terms of Keirsey personality types, namely Idealist and gender who have Idealist personalities. Descriptive qualitative research was used in this research and was carried out at Junior High School Negeri 1 Purwodadi in the 2019/2020 school year. The research was conducted on the subject of class VIII I with idealist personality type, then selected 1 female student and 1 male student using purposive sampling. The researcher is the main research instrument with the help of observation guidelines, questionnaires, tests of mathematical communication skills and then interviews. The data collection technique is a triangulation technique by comparing the answers to the mathematical communication skills test and interviews. Data reduction, data presentation and drawing conclusions are data analysis techniques used in this study. Female students with idealist personality types communicate better mathematically than male students with idealist personality types as shown in the results of this study. 
Toyohashi University of Technology: The Direction the Center for Human-Robot Symbiosis Research Should Take and its Achievements to Date
Authors: Terashima Kazuhiko ,   Toyohashi University of Technology 1-1 Hibarigaoka, Tempaku-cho, Toyohashi 441-8580, Japan [Received: January 7, 2021]
Published: February 2021

In the preface of this special issue, we will discuss the achievements of the Toyohashi University of Technology and the Center for Human-Robot Symbiosis Research so far and the direction they should proceed in hereafter. In particular, the history of the establishment of the center, research results until now, future activity plans, and this special issue are described.
Generation of Optimal Coverage Paths for Mobile Robots Using Hybrid Genetic Algorithm
Authors: Schäfle Tobias Rainer , Mitschke Marcel , Uchiyama Naoki ,   Department of Mechanical Engineering, Toyohashi University of Technology 1-1 Hibarigaoka, Tempaku, Toyohashi, Aichi 441-8580, Japan,   Andreas Stihl AG & Co. KG Badstraße 115, Waiblingen 71336, Germany
Published: February 2021

This paper presents new optimal offline approaches to solve the coverage path planning problem. A novel hybrid genetic algorithm (HGA), which uses, the turn-away starting point and backtracking spiral algorithms for performing local search, is proposed for grid-based environmental representations. The HGA algorithm is validated using the following three different fitness functions: the number of cell visits, traveling time, and a new energy fitness function based on experimentally acquired energy values of fundamental motions. Computational results show that compared to conventional methods, HGA improves paths up to 38.4%; moreover, HGAs have a consistent fitness for different starting positions in an environment. Furthermore, experimental results prove the validity of the fitness function.
Development and Experimental Verification of a Person Tracking System of Mobile Robots Using Sensor Fusion of Inertial Measurement Unit and Laser Range Finder for Occlusion Avoidance
Authors: Funato Kazuhiro , Tasaki Ryosuke , Sakurai Hiroto , Terashima Kazuhiko ,   Toyohashi University of Technology 1-1 Hibarigaoka, Tempaku-cho, Toyohashi, Aichi 441-8580, Japan,   Aoyama Gakuin University 5-10-1 Fuchinobe, Chuo-ku, Sagamihara, Kanagawa 252-5258, Japan
Published: February 2021

The authors have been developing a mobile robot to assist doctors in hospitals in managing medical tools and patient electronic medical records. The robot tracks behind a mobile medical worker while maintaining a constant distance from the worker. However, it was difficult to detect objects in the sensor’s invisible region, called occlusion. In this study, we propose a sensor fusion method to estimate the position of a robot tracking target indirectly by an inertial measurement unit (IMU) in addition to the direct measurement by an laser range finder (LRF) and develop a human tracking system to avoid occlusion by a mobile robot. Based on this, we perform detailed experimental verification of tracking a specified person to verify the validity of the proposed method.
Study on Automatic Operation of Manual Wheelchair Prototype and Basic Experiments
Authors: Tobita Kazuteru ,   Shizuoka Institute of Science and Technology 2200-2 Toyosawa, Fukuroi-shi, Shizuoka 437-8555, Japan, Shikanai Yoshihito , Mima Kazuhiro
Published: February 2021

In nursing homes, repeatedly guiding several carereceivers in wheelchairs before and after meals is one of the factors that increase the burden on caregivers. A solution to this problem is to incorporate autonomous mobility functions into the wheelchair. Although many autonomous electric wheelchairs have been developed in the past, it is not reasonable to introduce them to all users of nursing homes from the standpoint of cost, charging, and maintenance. In this study, we are developing a detachable robot that can operate a manual wheelchair autonomously. The basic concept, target specifications, and design conditions are defined herein, and the results of basic experiments such as straight-line stability tests, obstacle sensor measurement tests, and self-position estimation are reported. The implementation of autonomous driving functions such as path generation and localization will be promoted in the future.
Effects of Presenting People Flow Information by Vibrotactile Stimulation for Visually Impaired People on Behavior Decision
Authors: Fujino Kanon ,   Department of Precision Mechanics, Chuo University  1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan, Niitsuma Mihoko
Published: February 2021

Many studies have been conducted on walking support for visually impaired people. However, only a few studies have contributed to the wide understanding of their surrounding environment. In this study, the focus was on the flow of people in environmental information. The flow of people is formed by the presence of many pedestrians in the surroundings of the walking environment. If visually impaired people can independently make decisions by grasping the dynamic environment of people flow, they can walk with ease and peace of mind. A method is proposed that extracts people flow information and selects the information necessary for understanding the environment. The method utilizes vibrotactile stimulation. The effectiveness of the proposed method in determining the surrounding environment and the influence of vibration information on behavior decisions were verified.
Repositioning the Independence of The Indonesian Waqf Board in the Development of National Waqf: A Critical Review of Law No. 41 of 2004 Concerning Waqf
Authors: Rimanto Rimanto , Zulhuda Sonny , Hermanto Agus
Published: February 2021

Juridically, the laws and regulations have weakened the Indonesian Waqf Board (BWI) in the regulation of waqf, so that the set goals of the Indonesian Waqf Board have not fully achieved, including advancing and developing national waqf. The overlapping management and supervision of waqf by other institutions is suspected of causing BWI’s duties and authorities’ inadequacy. Besides, several crucial problems, including the Indonesian Waqf Board (BWI), have implications for the stagnation of BWI provisions’ implementation. These regulations have not been followed by the Indonesian Muslim community as a whole. What is interesting to examine is why the Indonesian Waqf Board is unable to function correctly? This study’s objective was to find ideal constructions about the position, duties, and authorities of BWI in advancing and developing national waqf. This study was a scientific evaluation with its qualitative-descriptive-analytical characteristics. The method used was qualitative analysis, and the results were presented descriptively. The pattern of reconstructing authority of the Indonesian Waqf Board (BWI) was a study of Law Number 41 of 2004 concerning Waqf so that articles were compiled to lead to a genuinely independent, credible, and robust board in the governance of the Republic of Indonesia. Besides, it is necessary to have accreditation for BWI so that its management’s standardization is credible.Secara yuridis peraturan perundang-undangan terdapat pelemahan terhadap kedudukan Badan Wakaf Indonesia (BWI) dalam pengaturan perwakafan, sehingga berdampak pada belum sepenuhnya tercapai tujuan Badan Wakaf Indonesia dibentuk, yaitu memajukan dan mengembangkan perwakafan nasional. Adanya timpangtindih pembinaan dan pengawasan wakaf oleh lembaga lain, diduga sebagai penyebab tidak maksimalnya tugas dan wewanang BWI. Selain itu, ada  beberapa problematika yang krusial, tidak jelasnya status independensinya Badan Wakaf Indonesia (BWI) yang berimplikasi pada stagnansi pelaksanaan ketentuan BWI sehingga aturan tersebut belum diikuti oleh masyarakat Muslim Indonesia secara keseluruhan. Yang menarik untuk dikaji adalah mengapa Badan Wakaf Indonesia tidak dapat berfungsi sebagaimana mestinya? Tujuan penelitian ini untuk menemukan kontruksi edeal tentang kedudukan, tugas serta wewenang BWI dalam memajukan dan mengembangkan perwakafan nasional. Penelitian ini merupakan evaluasi ilmiah dengan sifatnya yakni kualitatif-deskriptif-analitis. Metode yang digunakan adalah analisa kualitatif, dan hasilnya disajikan secara deskriptif. Pola rekonstruksi toritas Badan Wakaf Indonesia (BWI) adalah penelitian terhadap Undang-Undang Nomor 41 Tahun 2004 Tentang Wakaf, sehingga tersusun pasal tentang BWI yang dapat menjadikan badan yang benar-benar independen, kridibel serta kuat dalam tata kelola pemerintahan Republik Indioonesia perlu adanya akreditasi terhadap BWI agar standarisasi pengelolaannya kredibel.
Towards New Sharia Governance for Islamic Financial Institutions
Authors: Abozaid Abdulazeem
Published: February 2021

Since its inception a few decades ago, the industry of Islamic banking and finance has been regulating itself in terms of Sharia governance. Although some regulatory authorities from within the industry, such as Accounting and Auditing Organization for Islamic Financial Institutions (AAOIFI) and Islamic Financial Services Board (IFSB), the Islamic banking and finance industry remains to a great extent self-regulated. This is because none of the resolutions or the regulatory authorities' standards are binding on the Islamic financial institution except when the institution itself willingly chooses to bind itself by them. Few countries have enforced some Sharia-governance-related regulations on their Islamic banks. However, in most cases, these regulations do not go beyond the requirement to formulate some Sharia controlling bodies, which are practically left to the same operating banks. Furthermore, some of the few existing regulatory authorities' standards and resolutions are conflicted with other resolutions issued by Fiqh academies. The paper addresses those issues by highlighting the shortcomings and then proposing the necessary reforms to help reach effective Shariah governance that would protect the industry from within and help it achieve its goals. The paper concludes by proposing a Shariah governance model that should overcome the challenges addressed in the study.Pada awal berdiri, Lembaga Keuangan Syariah merupakan lembaga keuangan yang menerapkan Hukum Syariah secara mandiri dalam sistem operasionalnya. Ia tidak tunduk pada peraturan lembaga keuangan konvensional, sehingga dapat terus berkomiten dalam menerapkan Hukum Syariah secara benar. Selanjutnya, muncullah beberapa otoritas peraturan yang berasal dari pengembangan Lembaga Keuangan Syariah. Diantaranya adalah Islamic Financial Services Board (IFSB) dan Accounting and Auditing Organization for Islamic Financial Institutions (AAOIFI). Hal ini tidak menyimpang dari kerangka peraturan Hukum Syariah, sebab standar peraturan dan keputusan yang dikeluarkan ditujukan khusus untuk Lembaga Keuangan Syariah saja. Beberapa Negara telah menerapkan peraturan tata kelola Hukum Syariah pada Bank Syariah mereka. Namun dalam banyak kasus, peraturan yang diterapkan tidak mampu mengontrol Lembaga Keuangan Syariah tersebut secara penuh. Sehingga, secara praktis proses pengawasan diserahkan kepada lembaga keuangan yang beroperasi. Akan tetapi, beberapa standar dan keputusan yang dikeluarkan oleh sebagian pemangku kebijakan bertentangan dengan keputusan yang dikeluarkan oleh beberapa akademi Fiqh. Artikel ini ditulis untuk menyoroti permasalahan yang timbul pada tata kelola Lembaga Keuangan Syariah, khususnya kekurangan yang tampak pada sistem tata kelola. Kemudian, penulis akan mengajukan usulan tentang efektifitas tata kelola Lembaga Keuangan Syariah yang bebas dari permasalahan.
Successful Application of Clusterization Development Strategy for Small and Scattered Fields
Authors: Wang Ruifeng , Xiaoling Yi , Xintao Yuan
Published: February 2021

This paper demonstrates an innovative clusterization approach to define development strategy for small and scattered fields in T Basin, which is located in landlocked central Africa. As a rifted basin, T basin is around 250 km long and 80 km wide under sub-Saharan desert environment. The operator started exploration in 2008 and had discovered over 40 oil fields scattered over the whole basin but with limited size. 30 small oilfields occupy only 20% of total OOIP. Therefore the discovered fields in T basin belong to small and scattered fields. To realize fast track development in landlocked desert and achieve economic robustness meanwhile is the huge challenge for the operator. Clusterization development strategy had been put forward to realize integrated asset development.

Clusterization is to define several oil field clusters based on the criteria of adjacency, reservoir characteristics etc. Each oil field cluster should have one and/or two relatively bigger oil field as the central fields. Satellite fields are grouped into adjacent central fields thus forming oil field clusters. The whole basin development optimization could be carried out on a two-tier level: 1) for the intra cluster level, central fields will be commissioned first and satellite fields could be ranked to substitute production plateau, satellite fields facilities could be skid-mounted and shared among satellite fields to reduce Capx. 2) for the oilfield cluster level, clusters could be ranked according to criteria of OOIP scale, productivity projection and commissioning complexity. Relatively concentrated oilfield clusters could be prioritized to arrive at long term production projection. The remaining clusters could serve as plateau maintenance purpose afterwards.

Five oilfield clusters had been defined under the guidance of clusterization strategy. Three oilfield clusters had been recommended for Phase I production after optimization on the inter-cluster and intra-cluster level. 60 KBOPD of productivity with longer plateau is expected from clusterization development with convincing economical parameters, which fully satisfy the requirement of long distance pipeline.

This paper had proposed an innovative clusterization approach to define development strategy for small and scattered oilfields in a landlocked basin. The two-tier optimization process inherent in the clusterization approach could be of strong reference value to similar marginal blocks and basins.
Petroleum Exploration Potential on Abu Gabra Formations in Fula Sub-basin, Muglad Basin, Sudan
Authors: Weili Ke , Guangya Zhang , Aixiang Liu , Yonglin Zheng , Yongjun Yu
Published: February 2021

Fula sub-basin is one of chasmic structure units with rich petroleum accumulation within Muglad basin. In the past, thick sandstones of Bentiu was considered as main petroleum accumulation targets sealed by faults and anticlines, and most petroleum generated by AG source kitchen has migrated to upper formations along big faults, and furthermore, sandstones inside AG formation of are thin with poor permeability and porosity caused by compaction. Recently, some works have been done specially on AG formation, including small fault interpretation, seismic sedimentary analysis and thin layer inversion, resulting in new petroleum discoveries within middle AG formation, which reveals that AG formation has also good petroleum accumulation abilities.

Comprehensive study shows that there developed many small faults within AG period, which could seal sandstones of AG formation laterally, forming effective faulted block within AG formation. Sandstones of delta and sub-water channel could be found. Within AG4 and AG2 formations, there are mainly lacustrine facies. Channel sandstones occurred regression and the area of alluvium fan decreased AG shale has high matter abundance, high hydrocarbon generating potential and kerogen type I, II with middle to high mature, showing good hydrocarbon generation ability. Although sandstones of AG formation have relatively low permeability and porosity, these sandstone have good logging response on hydrocarbon could be sealed by local surrounding mudstones and. All above reveals that AG combination is near-source reservoir combination.

Low-amplitude anticline and structure-lithology reservoir models are favorite reservoir models in Fula sub-basin. In the west slope, especially the lower places of the slope are the areas of huge sedimentary accumulation should be favorite prospects. As for the east slope, low-amplitude anticline bounded by small faults that developed during AG period should be the favorite area for exploration, which has been proved by successful drilling activities.

In Fula sub-basin, AG structure-lithology complex reservoir combination should be the favorite type for drilling as per under these two key factors, the petroleum could be well accumulated. Currently, there have two important petroleum discoveries of channel sandstone and delta sheet sandstone in AG formation, proving that AG formation still has good potential for drilling.
Appraising Carbon Geological Storage Potential in Unconventional Reservoirs Using Well-Testing Method: Engineering Parameters Analysis
Authors: Chen Z. M. , Liao X. W. , Zhao X. L. , Li X. J. , Jiang W. L. , Zhu L. T. , Wang L. , Xia Y. H.
Published: February 2021

Most of work focus on influences of reservoir parameters of depleted shales on carbon storage capacity. This is useful for selecting a good candidate as a repository. However, engineering parameters of shales are also important factors for carbon sequestration. So, necessary work is still needed.

Following a detailed introduction of a trilinear flow model for carbon sequestration (Chen et al., 2016), this paper continues to study impacts of engineering parameters on carbon storage potential. Firstly, the methodology for appraising carbon sequestration potential was introduced, containing (1) introducing the conceptual model, (2) developing the mathematical model, (3) obtaining the wellbore-pressure solution, (4) determining the injection time, and (5) appraising the carbon sequestration capacity. In the conceptual model, the shale formation were divided into two subsystems and three regions, including matrix subsystem, natural-fracture subsystems, hydraulic-fracture region, inner region, and outer region. With basic equations, a mathematical model was developed in those subsystems and regions. Then, based on the mathematical model, CO2 storage potential in abandoned shales was investigated at different values of fracture conductivity, fracture number, fracture length, inner permeability, and wellbore length. This meaningful work provides a guideline to select wells and monitoring facilities for storing CO2 in residual depleted shale reservoirs.
Regional Geological Study and Potential Prediction of the Rio Del Rey Basin (RDR), Offshore Cameroon
Authors: Altayeb Khalid O. , Yushan Su , Shixiang Wu , Zhankun Chen
Published: February 2021

Located in the eastern end of Niger delta; the Rio Del Rey (RDR) basin has a unique, complex multi-staged geological features and different types of Structures. This study has aimed to better understand the different structural and stratigraphic setting of the fields within the RDR basin and the way they control the hydrocarbon occurrences. To do that, an integrated 2D and 3D seismic interpretation was done targeting the toe thrust boundary, the upper Cretaceous unconformity and four key horizons of different depth levels in the Tertiary formations. Twelve regional profiles of contrastive orientations that cover the whole basin were interpreted to identify the regional structures; well correlation was done to identify the shallower tertiary settings while additional detailed grids of interpretation at the northeastern and southwestern corners and the seismic facies analysis of the whole RDR study area were used to classify the stratigraphic setting at the deeper regions. The results have revealed that the RDR basin is mainly controlled by thrusting, diapirism and detachment fault structures. The major toe thrust zone is found southern of Ngosso and trends in the northeast-southwestern direction. Gravitational tectonism becomes the primary deformation process shaping the structures as the sediments accumulation increases to the south and consequently, several shale ridges were formed. These ridges and their lateral movement from North to South along with the whole sediments increasing have caused a slope instability of the lower ductile Akata shale formation; what caused the forming of the detachment faults zone in the Northern and middle parts of the RDR basin. The Oongue Turbidites of Eocene were deposited in the northeastern part of the basin in deep water fans by the main sediments supply from the North and the East with various sand thicknesses due to the structural system. The hydrocarbon potential accumulations are found in the mid to upper Tertiary formations and the deeper Upper Cretaceous, but most of the oil and gas fields are located in shallower deltaic reservoirs associated with fault-bounded traps related to shale ridges and diapir structures. Considerable amounts of hydrocarbons were also found within the turbidites sands of Oongue (NE) and Isongo (SE).
Application of Analytic Hierarchy Process to Identify the Most Influencing Human Factors (HFs) and Performance Influencing Factors (PIFs) in Process Safety Accidents
Authors: Theophilus Stephen C. , Abikoye Olayinka G. , Arewa Andrew O. , Ifelebuegu Augustine O. , Esenowo Victor
Published: February 2021

Numerous studies suggest that 80% of accidents in hydrocarbon processing industries are as a result of human factors (HFs). While a lot is known of human factor influence to process accident, the effects of performance influencing factors (PIFs) on human factors in process accidents is not yet well understood. This study examined HFs and PIFs which influences the propagation of undesired occurrences in hydrocarbon processing industries. An illustrative case study of the Tesoro refinery accident was analysed. To affirm consistency in judgments, Analytic Hierarchy Process AHP – a multi-criteria decision-making method was used in identifying HFs and PIFs of critical events. BPMSG AHP computer program was also used to validate results obtained from the manual calculations. Three critical events namely non-routine operations (Event 1), manual manipulation of several isolation block valves (Event 2) and automated start-up operations of Naphtha Hydro-Treating unit (Event 3) were identified. The ranking of PIFs revealed that Procedures, Level of Supervision, Task Characteristics, and Skill Level were major influencing factors to the event. Analysis of human factors revealed that Job Factors had the most significant influence (41%), while the Individual Factors and Organisational Factors had (31%) and (28%) influence respectively. The consistency index (CI) and consistency ratios (CR) of the PIFs were 0.174 and 0.193 for critical Event 1; 0.170 and 0.120 for critical Event 2; and, 0.037 and 0.033 for critical Event 3 respectively. This showed consistency in judgments of the study on PIFs selected for the critical events identified. The Tesoro refinery accident was due to latent organisational and cultural failures.
United States Experience Regulating Unconventional Oil and Gas Development
Authors: Allison Edith
Published: February 2021

In the midst of aggressive anti-drilling campaigns by environmental organizations and well-publicized complaints by citizens unaccustomed to oil and gas operations, rigorous studies of unconventional oil and gas development show that there are no widespread or systemic impacts on drinking water resources in the United States. In addition, air pollution and greenhouse gas emissions have significantly declined with the growth in natural gas production and its use in power generation. Furthermore, induced seismicity from subsurface waste disposal has plummeted in response to industry initiatives and new regulations. This record of environmental protection reflects the fact that U.S. hydraulic fracturing, like other oil and gas operations, is highly regulated by the states. In addition, air emissions, operations on federal lands, and subsurface injection are subject to federal regulation.

Academic and government researchers have documented that chemicals and gas produced by hydraulic fracturing are not contaminating drinking water. However, as an added complication, methane occurs naturally in drinking water aquifers in some producing areas. In 2015, the U.S. Environmental Protection Agency (EPA) completed a four-year study of potential aquifer contamination from hydraulic fracturing and associated industry operations. The report found some impacts on drinking water including contamination of drinking water wells; however, the number of cases was small compared to the number of wells hydraulically fractured. The scientific peer-review and public critique of the study, which continues after more than a year, may recommend additional research.

The emotionally charged, anti-fracking campaigns provided important lessons to U.S. operators: pre-drilling, baseline data on water and air quality are essential to answering public concerns; infrastructure issues such as increased truck traffic on small, local roads are important to residents; and the initial failure to disclose the composition of hydraulic fracturing fluid intensified public concern.
Cost Reduction Strategies in Workover operations in the Face of Low Oil Price: The Agbada Workover Project
Authors: Eze Joy , Onakomaiya Oluwarotimi , Ogunrinde Ademola , Adegboyega Olusegun , Wopara James , Timibitei Fred , Ideh Matthew
Published: February 2021

The current low oil price has resulted in several continuous improvement drives particularly focused on capital efficiency. With over 60 producing oil fields and approximately 700 producing wells, some of which date back to the 60s, work over operations in Shell Petroleum Development Company (SPDC) is imperative. Having completed over twenty (20) Work Over operations in the last six years in SPDC, the importance of Work Over operations as a means to sustain production especially for relatively old, dysfunctional or non-compliant wells and keep the production funnel full at a relatively lower cost compared to new drills is more evident. Work over operations, defined as the repair and/or stimulation of existing wells in order to improve production performance presents the opportunity to maximize short term gains from already existing facilities.

The objective of the workover operations on Agbada ABC and XYZ was to restore well integrity with the installation of sub surface safety valves and gas lift mandrels instead of insert orifice while assuring the development of oil and associated gas. The insert orifice had been installed on both wells to enable gas lift operations from the Agbada Associated Gas Gathering (AGG) plant since they were unable to sustain natural flow. However, due to epileptic AGG, both wells quit frequently requiring nitrogen lift with an average Non-Productive Times (NPT) of 6 months per year while Agbada XYZ was put on cyclic production and had been a pressure build-up well with at least two weeks down time per month. The workover operation was therefore proposed to replace the existing (punched) tubing, install proper gas lift mandrels for optimum performance, reduce well operating cost arising from AGG outage and/or compressor failure and restore production in the reservoir.

This paper aims to discuss the cost reduction strategies such as collaboration, re-use, program optimization and operational efficiency applied in driving down Non-Productive Times (NPT) in the efficient delivery of these workover operations which resulted in <6% NPT, >30% time savings, ca. 40% cost savings and early return of wells to production.
Annular Barrier as an Alternative to Squeezes in Challenging Wells: Technology Review and Case Histories
Authors: Bagal Joseph , Onadeko Gbenga , Hazel Paul , Dagestad Vibjørn
Published: February 2021

The drilling industry has always relied on cement as a primary barrier. Although the cement represents about 5% of the well cost, when squeezes are required, cementing averages 17% of the well cost. Only 50% of the squeezes achieve the objective of establishing a barrier for well integrity. A little bit more than half of the failures can be attributed to operational challenges (pump failure, cement contamination), or design oversights (cement recipe, centralizers). However there are still cement failures with perfect design and field execution. These failures typically exhibit some of the following characteristics: high deviation, high pressure, washouts, natural fractures, long casing section, heterogeneous sands.

For these specific conditions, it is beneficial to add an assurance that would maintain the integrity of the well even in case of bad cement. Some of the assurances used include port collars, external casing packers (ECP) and swell packers. Port collars allow a squeeze above the first stage cement, while ECP serves as a base for a second stage cement, and swell packers provides a baffle for sustained casing pressure. A more recent technology is the well annular barrier that can form a combined barrier with cement, and can also be used as a stand-alone primary barrier.

The well annular barrier is a metal-expandable barrier that is expanded with hydraulic pressure. It is full bore, highly customizable, and qualified to ISO 14310. The metallurgy allows the packer to shape fit into either an open hole with irregular geometry or inside a casing to preclude annular pressure build up by giving a life-of-well reliable seal. The well annular barrier has been deployed in a variety of wells to achieve well integrity with and without cement, protect the B-annulus from sustained casing pressure, or serve as a barrier between reservoirs that cannot be commingled.

This paper performs a review of the technologies used for cement assurance, their advantages and disadvantages. Case histories of well annular barrier deployments are presented, including a case where the well annular barrier was used as a stand-alone well barrier element without the need for dispensation. This paper also discusses how the well annular barrier fits into the regulatory requirements for well construction providing to the drilling industry an alternative to cement for the purpose of well integrity.
Diagnosis patterns of sickle cell disease in Ghana: a secondary analysis using cohort data
Authors: Sims Alexandra M. , Bonsu Kwaku Osei , Urbonya Rebekah , Farooq Fatima , Tavernier Fitz , Yamamoto Marianna , VanOmen Sheri , Halford Brittne , Gorodinsky Polina , Issaka Rachel , Kpadenou Tulana , Douglas Rhonda , Wilson Samuel , Fu Clementine , Canter Danielle , Martin Duña , Novarra Austin , Graham Lewis , Sey Fredericka , Antwi-Boasiako Charles , Segbefia Cathy , Rodrigues Onike , Campbell Andrew
Published: February 2021

Background:

Despite having the highest prevalence of sickle cell disease (SCD), Sub-Saharan Africa lacks a robust screening program. We sought to capture the diagnosis patterns of SCD, particularly age and mechanism at SCD and age of first pain crisis, in Accra, Ghana.
Methods

We administered a survey to parents of offspring with SCD between 2009–2013 in Accra as a part of a larger cohort study and analyzed a subset of the data to determine diagnosis patterns. Univariate analyses were performed on diagnostic patterns; bivariate analyses were conducted to determine if patterns differ by offspring’s age, or their disease severity. Pearson’s chi-squared were calculated.
Results

Data was collected on 354 unique participants from parents. 44% were diagnosed with SCD by age four; 46% had experienced a pain crisis by the same age. 66% were diagnosed during pain crisis, either in acute (49%) or primary care (17%) settings. Younger (< 18 years) offspring were diagnosed with SCD at an earlier age (74% by four years old); in the adult ( > = 18 years) group, 30% were diagnosed by four years (p < 0.001). Few were diagnosed via newborn screen. Half with severe disease were diagnosed by age four, compared to 31% with mild disease (p = 0.009).
Conclusions

These findings reflect a reliance on diagnosis in acute settings, and a relative underutilization of systematic screening programs. By understanding current patterns, opportunities remain to more effectively detect and treat SCD in this high prevalence population.
Multiscale imaging of the rat brain using an integrated diceCT and histology workflow
Authors: Gignac Paul M. , O’Brien Haley D. , Sanchez Jimena , Sanroman Dolores Vazquez
Published: February 2021

Advancements in tissue visualization techniques have spurred significant gains in the biomedical sciences by enabling researchers to integrate their datasets across anatomical scales. Of particular import are techniques that enable the interpolation of multiple hierarchical scales in samples taken from the same individuals. This study demonstrates that two-dimensional histology techniques can be employed on neural tissues following three-dimensional diffusible iodine-based contrast-enhanced computed tomography (diceCT) without causing tissue degradation. This represents the first step toward a multiscale pipeline for brain visualization. We studied brains from adolescent male Sprague-Dawley rats, comparing experimental (diceCT-stained then de-stained) to control (without diceCT) brains to evaluate neural tissues for immunolabeling integrity, compare somata sizes, and distinguish neurons from glial cells within the telencephalon and diencephalon. We hypothesized that if experimental and control samples do not differ significantly in quantitative metrics, brain tissues are robust to the chemical, temperature, and radiation environments required for these multiple, successive imaging protocols. Visualizations for experimental brains were first captured via micro-computed tomography scanning of isolated, iodine-infused specimens. Samples were then cleared of iodine, serially sectioned, and prepared again using immunofluorescent, fluorescent, and cresyl violet labeling, followed by imaging with confocal and light microscopy, respectively. Our results show that many neural targets are resilient to diceCT imaging and compatible with downstream histological staining as part of a low-cost, multiscale brain imaging pipeline.
Examining of the countries in terms of water resources along with the effect of climate change by time series clustering
Authors: akay özlem
Published: February 2021

Today, the problem of climate change is addressed in many ways. The most important effect of climate change is the disruption of the water cycle. Therefore, the location and timing of the water resources in the world are changing. Water is an indispensable resource that connects all living things together and directly affects their lives. Water is not only a biological requirement for man, but also for economic, social, and cultural life itself. However, this resource, which is of vital importance, exists unfortunately in a limited amount on earth. This study aims to identify similar countries in terms of water resources by taking into account the changes in precipitation amounts together with climate change. For this purpose, a time series clustering analysis was conducted to precipitation amounts of 21 countries between 2009-2017 with the Hierarchical clustering and Partitioning Around Medoids (PAM) clustering methods. Countries are divided into two clusters and they were evaluated according to their water risk levels and populations. It should be noted that countries with low precipitation, high risk of water, and a high population should take urgent measures for climate change.
The prediction and assessment of the intrauterine fetal with umbilical cord around neck well-being by daily fetal movement counting chart (DFMC)
Authors: li zijun , Zhou Xin , Zheng Yaqin , Liu Min , Fu Xiaoying , Ye Aimei
Published: February 2021

Background

Currently, FM is a sole subjective index which depends on self-assessment of pregnant women, and it can objectively reflect the well being of intrauterine fetus. It has been the focus of obstetricians' research and attention how to quantify fetal movement (FM) and change it into a relatively objective evaluation index. We sought to predict and evaluate the well being of intrauterine fetal with umbilical cord around the neck (UCAN) by performance of daily fetal movement counting chart (DFMC).
Methods

To retrospectively select 100-case pregnant women who met the enrolled requirements, and whether the fetal was intrauterine safety or not was predicted by analysis of the DFMC before delivery. According to the different perinatal outcomes after delivery, 100-cases pregnant women were divided into intrauterine safety (IUS) group (44 cases) and intrauterine unsafe (IUNS) group (56 cases). And the independent risk factors of fetal intrauterine safety, including maternal age, gestational week, umbilical artery systolic blood flow to diastolic blood flow ratio (S/D), amniotic fluid index (AFI), modified Fischer score of non stress test (NST), DFMC and mode of delivery were analyzed by multi-factors Binary Logistic Regression.
Results

Only FM and mode of delivery were independent risk factors affecting fetal safety intrauterine (all p value < 0.05). There was no remarkable difference between DFMC prediction and clinical retrospective evaluation of fetal safety in natural delivery and forceps delivery (all P value > 0.05), except in cesarean section (p < 0.05). The sensitivity, specificity and Yuden index of DFMC for predicting the intrauterine safety in natural vaginal delivery were 86.5%, 90.0% and 0.77 respectively, and in cesarean section were 66.7%, 94.6% and 0.61, respectively. Abnormal DFMC may account for the highest proportion of emergency cesarean section (87.5%, 35/40).
Conclusions

DFMC can effectively predict and evaluate the well being of intrauterine fetus with UCAN. At the same time, it can also provide limited clinical proofs for pregnant women with UCAN to choose model of delivery.
Could the Crosstalk Between Mdscs and Tregs Have a Role in β-thalassemia?
Authors: Zahran Asmaa M , El-Badawy Omnia , Badawy Eman R. , Ghazaly Marwa , Saad Khaled , Mahmoud Khalid Hashim , Elhoufey Amira , Elsayh Khalid I.
Published: February 2021

Background: Secondary-iron overload, alloimmunization, and increased risk of infections are common complications in β-thalassemia major (BTM) patients. Tregs and myeloid-derived suppressor cells (MDSCs) play an essential role in preventing excessive immune responses. This research aimed to investigate the interaction between Tregs and MDSCs in BTM patients and their relation with disease severity.Methods: This case-control study included 26 patients with BTM and 23 healthy age- and sex-matched controls. All patients were investigated for complete blood picture, serum ferritin, and flow cytometric analysis of peripheral blood to detect Tregs, MDSCs, and MDSC subsets.Results: A significant increase was observed in the frequencies of Tregs and MDSCs, particularly MO-MDSCs, in the patients compared with the controls. These cells also showed direct relations with ferritin and TLC and an inverse association with hemoglobin. Furthermore, a positive correlation was seen between Tregs and each of the total MDSCs and MO-MDSCs. Conclusion: Our findings highlight the role Tregs and MDSCs cooperatively plays in the BTM and their importance in suppressing the high activity of the immune system found in those patients due to repeated blood transfusions and antigenic stimulation.
Recurrent KRAS Mutation and Co-mutation of KIT and SF3B1 in Melanoma of the Female Genital Tract
Authors: Cai Yuan-jun , Ke Long-feng , Zhang Wen-wen , Lu Jian-ping , Chen Yan-ping
Published: February 2021

Background: Malignant melanoma of the female genital tract is relatively uncommon and accounts for 5% of all melanomas in women. This study aimed to identify driver genes in melanoma of the female genital tract with the purpose of enhancing understanding of disease pathogenesis and identifying potential new therapeutic targets to develop effective therapies. Methods: KIT (CD117) and BRAF expression were detected immunohistochemically. Polymerase Chain Reaction (PCR) and Sanger sequencing techniques were performed to identify the mutational status of BRAF, NRAS, KRAS, NF1, KIT, PDGFRA and SF3B1 on 19 melanomas of the female genital tract, paired with 25 cutaneous melanomas, 18 acral melanomas and 11 melanomas of nasal cavity. Results: Somatic variant analysis identified KRAS (6/19; 32%) as the most commonly mutated gene, followed by KIT (4/19; 21%), SF3B1 (3/19; 16%) and NRAS (1/19; 5%). None of the cases were found to harbor BRAF, NF1 and PDGFRA mutations in melanomas of the female genital tract. However, none of the cases were found to harbor SF3B1 and KIT mutations in cutaneous melanomas, acral melanomas and melanomas of nasal cavity. Recurrent KIT mutations, as well as mutations in the less frequently mutated genes NRAS and SF3B1, were exclusively detected in vulvovaginal melanomas, but not in tumors arising in the cervix. However, recurrent KRAS mutations were detected in similar frequencies in tumors of the vulva, vagina, and cervix. Additionally, recurrent KRAS and KIT mutations occurred predominantly in polygonal and epithelioid cell types of melanoma in the female genital tract. Immunohistochemistry revealed moderate or strong cytoplasmic CD117 expression in 6 of the 19 cases (31.6%).Conclusions: We observed that gynecologic melanoma harbored distinct mutation rates in the KIT, BRAF, SF3B1, KRAS, and NRAS genes. Our findings support the notion that gynecologic melanoma is a distinct entity from non-gynecologic melanoma, and these findings offer insights into future therapeutic options for these patients.