bluuebunny/crossref_metadata_2025 huggingface dataset:
Time to Survive
Authors: Cherkasov P.
Published: February 2021

The article covers one of the most difficult periods in IMEMO history, which dates back to 1990s, when Russia was going through the deepest (since 1917) structural transformation. This transformation also affected the field of science, which significantly lost its former government support. Allocations from the budget (less than 40% as compared to the previous period) were not enough even to pay wages to employees, aside from material and technical provision of researches. Research institutes, being part of the Russian Academy of Sciences, were forced to look for additional sources of funding to provide financial support to scientists and further researches. IMEMO was not an exception. Amid massive brain drain of the most skillful young scientists from the field of science, the IMEMO management by all chances strived for retaining the core of the scientific potential. All resorts were exploited: space was leased, separate scientific and commercial enterprises of small business were established within the IMEMO territory, search for grants both domestically and abroad was encouraged, employees assignment to foreign scientific centers was practiced, double job holding was rewarded for those who needed it. From the money raised, the Fund of Scientific, Technical and Social Development of the Institute and the Fund of Social Support to Scientists were established, which helped mitigate the financial situation among employees. In 1990s, IMEMO was one of the rare institutes of the Russian Academy of Sciences not to practice delay in wages payment, with salaries volume exceeding those at similar academic centers, though the task was just to make both ends meet. Despite the difficulties, the research team continued to work. Books and articles appeared, international conferences were held, policy recommendations delivered. The “World Economy and International Relations” journal played a significant role publishing the results of the most interesting researches.
Post-Bipolar World: Peaceful Coexistence or Chaos?
Authors: Lukin A.
Published: February 2021

The article explores characteristics of the international relations bipolar system, changes occurred after its collapse and the future of post-bipolar world, focusing on the role of non-Western actors in it. On one hand, the bipolar system provided stability of international relations, but on the other – lead to competition between the U.S. and the USSR for the influence on the third countries, which sometimes resulted in armed conflicts in the third states. The collapse of the Soviet Union convinced the West both in the universality of its development model and the necessity to spread it all over the world. Now it is clear that the “democratism” ideology failed politically and culturally. The Western model has neither become a panacea for eliminating disparities between countries on different stages of development, nor the only example of successful and strong governance. New power centers, such as Russia, China, India and Brazil, have been successfully developing after the collapse of the Soviet Union. Their influence has been growing along with that of the West, and even though they did not necessarily directly confront it, they never shared all its values, yet never actively imposed their positions on the rest of the world. Regional powers (Nigeria, Venezuela, etc.) are also playing a more significant role in the emerging system, although sometimes they may join the alliances with more powerful countries to achieve their goals (as Vietnam does with the U.S. in its conflict with China). Russia’s reluctance to follow the West in its development created the first serious alternative to the existing unipolar world model and its values, so naturally and widely accepted by the Western actors. Whereas China with its rapid economic development is also posing a challenge to the ideology of "democratism" proving that the economic welfare is achievable outside the Western political model. As for Russia, its role in the modern world is still not defined. The Russian Federation wants to become an independent power unit and a center of the Eurasian integration. However, it is not clear whether it has resources of all kinds to implement this idea, – moreover, its economic dependence on the West is still too strong to insist on further confrontation. Instead, Russia (as well as its partners in the Eurasian Economic Union) could use Eurasian integration platforms to act as an "ambassador" of Asia in Europe and that of Europe in Asia. Acknowledgements. The article has been supported by the grant of the Faculty of World Economy and International Affairs, National Research University Higher School of Economics in 2016.
Beyond Hirsh-index: Status signals among Russian researchers
Authors: Sokolov M. M.
Published: February 2021

The article presents the results of a study of signals conveying positive or negative messages about social scientists. We surveyed sociologists actively publishing in the Russian language (N = 810). Subjects were asked to respond to a hypothetical situation in which they were to assess CVs of a fictional applicant for a grant competition. Attributes of scholars comprising a standard academic biography differed markedly both in their salience and in the degree of consensus about their importance. A book written single-handedly was the most unanimously recognized symbol of academic merit among Russian sociologists. The least agreement was about the signals related to the presence at the international intellectual scene (teaching in a “well-known European university”, publishing in international periodicals) and to the participation in dissertation production (supervising or serving as a reviewer of many dissertations). Importance of these groups of signals depends on the overall orientation to the local or global audience and age. There were much more consensus about the attributes in different ways discrediting scientists, such as plagiarizing or multiple publications.
Library science knowledge: continuity and dynamics
Authors: Varganova G. V.
Published: February 2021

Continuity of knowledge is the objective regularity of library science development. Library science is characterized by non- cumulated model of cognitive potential growth. The processes of new knowledge generation, actualization and complementation go on continuously, although unevenly, with varying degrees of intensity at different historical stages. The goal of the article is rationale for continuity and dynamics as the main instruments of library science knowledge development. The article is based on data analyses (including content-analyses) in the framework of methodology of inductive approach. Traditions and innovations are the main categories that provide continuality and dynamics in library knowledge growth and its further enhancement. The author considers the ideological impact on library science development, shows the influence of political changes on library science and the professional community. The article gives examples of Marxist ideology blocking the creation of new scientific ideas, determining the nature and content of research programs and the methodological tools chosen by scientists. Continuity in science can be strengthen by organization and fulfilling microhistorical researches. Portraits can creates a good basis for biographical and prosopographic research. Portraits of researchers presented in scientific, popular science, memoirs and other texts give an idea not only about their lives, but also about the features of the historical era. The role of creating portraits, as well as biographical and prosopographical research, is very important for understanding the processes of dynamics and continuity in the development of library science knowledge. Studying the professional career of practitioners and researchers allows getting answers to questions related to the origins of ideas, concepts, and theories, and helps tracing the complex path of transition from practical activities to library science. These types of research help to identify the social background of researchers, understand their beliefs and motivation to improve practice based on the use of scientific knowledge. Biographical and prosopographical research contributes to the removal of many misconceptions on the development of library science at different historical stages. Local history research is also important for studying and understanding the development of library science and the features of professional and personal life of researchers who have contributed to its cognitive enrichment. The integration of the results of local history, biographical and prosopographical research allows the creation a more complete picture of the development of library science in the historical perspective.
Children’s books in Canada: history of development and current issues
Authors: Pavlenko S. V.
Published: February 2021

The article studies the history of the development of children’s books in Canada. The author emphasises the main political, socio-economic and cultural factors that affect this process and form its unique characteristics. The hypothesis that «Canadian cultural identity» cannot yet be defined since it is continually, significantly affected by domestic issues and foreign cultures is proposed and analysed.

The author analyses the historical way of Canadian children’s book development. The different stages of this development are taken into account: from the total domination of foreign children’s books on the Canadian market to the resurrection and reflection of the First Nation people’s history and culture in the new books of Canadian writers. The author suggests that the modern stage of the Canadian Children’s books existence gives these books a power to become an instrument of Canadian cultural identification.

Different concepts of formation of the term Canadian children’s books are evaluated and their commonality and differences are underlined. The author defines the criteria that modern researchers, writers, publishers, cultural foundations and non-profit organizations use to describe the uniqueness of Canadian children’s books.

The system of government and private financial support for Canadian writers, illustrators and publishers is described. The main strategies for support and promotion of Canadian children’s books inside Canada are analysed.
American and Russian children’s literature at the beginning of the 21st century. The diversity of possibilities
Authors: Bukhina O. B.
Published: February 2021

Comparing changes in publication policies, the influence of translated books, and an important role that women writers play now, author analyzed new tendencies in American and Russian children’s and teens’ literature. The author concludes that American picture books reflect the varieties of contemporary experiences, and the Russian ones thrive with poetry and non-fiction. The comparison of teens’ literature of both countries shows a lot of similarities; both encompass more sensitive topics, such as illness, death, suicide, drugs, psychological trauma, and bulling.
Curriculum 2013 Based on The Philosophy Perspective of Progressivism
Authors: Noviyanti Ika Nurma
Published: February 2021

It should be understood that curriculum is the heart of education. The education curriculum in Indonesia has undergone various changes which are based on refining the previous curriculum as well as the 2013 Curriculum which synchronizes the previous curriculum. The philosophical foundation used in designing the curriculum is very important in determining educational goals. The results of the research show that the 2013 Curriculum can increase changes in knowledge, attitudes, and skills towards students for the realization of better character education. The 2013 curriculum has a goal of giving birth to an active, innovative and creative generation that aims to reduce ignorance, poverty and underdevelopment in life. The 2013 curriculum has a philosophical basis that adopts a foreign philosophy or is called an inclusive eclectic which is then synchronized with the Indonesian national education system. Progressivism is an educational philosophy that focuses on a process, where the 2013 Curriculum in theory focuses more on students. The 2013 curriculum illustrates if students must get learning that is in accordance with the development of the times in order to give birth to a generation of reformers and every competency in students is assessed as a whole both knowledge, attitudes, and skills.
Soft Robotics: Research, Challenges, and Prospects
Authors: Zhao Wenchuan ,   School of Mechanical Engineering, Shenyang University of Technology No.111, Shenliao West Road, Economic and Technological Development Zone, Shenyang 110870, China, Zhang Yu , Wang Ning
Published: February 2021

The soft robot is a kind of continuum robot, which is mainly made of soft elastic material or malleable material. It can be continuously deformed in a limited space, and can obtain energy in large bending or high curvature distortion. It has obvious advantages such as high security of human-computer interaction, strong adaptability of unstructured environment, high driving efficiency, low maintenance cost, etc. It has wide application prospects in the fields of industrial production, defense military, medical rehabilitation, exploration, and so on. From the perspective of the bionic mechanism, this paper introduces the soft robots corresponding to insect crawling, snake crawling, fish swimming, elephant trunk, arm, etc. According to different driving modes, the soft robots can be classified into pneumatic-hydraulic driven, intelligent material driven, chemical reaction driven, and so on. The mechanical modeling, control strategy, material, and manufacturing methods of soft robot are summarized, and the application fields of soft robot are introduced. This paper analyzes the main challenges faced by the research on the key technologies of soft robots, summarizes and analyzes them, and puts forward the prospects for the future research of soft robots. The development trend of the future is to develop the soft robot with the characteristics of micro-scale, rigid-flexible coupling, variable stiffness, multi-functional, high integration, and intelligence of driving sensor control.
Stabilization System for UAV Landing on Rough Ground by Adaptive 3D Sensing and High-Speed Landing Gear Adjustment
Authors: Ikura Mikihiro ,   Graduate School of Information Science and Technology, The University of Tokyo 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan, Miyashita Leo , Ishikawa Masatoshi
Published: February 2021

This paper proposes a real-time landing gear control system based on adaptive and high-speed 3D sensing to enable the safe landing of unmanned aerial vehicles (UAVs) on rough ground. The proposed system controls the measurement area on the ground according to the position and attitude of the UAV and enables high-speed 3D sensing of the focused areas in which the landing gears are expected to contact the ground. Furthermore, the spatio-temporal resolution of the measurement can be improved by focusing a measurement area and the proposed system can recognize the detailed shape of the ground and the dynamics. These detailed measurement results are used to control the lengths of the landing gears at high speed, and it is ensured that all the landing gears contact the ground simultaneously to reduce the instability at touchdown. In the experiment setup, the proposed system realized high-speed sensing for heights of contact points of two landing gears at a rate of 100 Hz and almost simultaneous contact on ground within 36 ms.
Modulation of Velocity Perception by Engine Vibration While Driving
Authors: Tachiiri Motoki ,   Nagoya Institute of Technology Gokisocho, Showa-ku, Nagoya, Aichi 466-8555, Japan, Tanaka Yoshihiro , Sano Akihito
Published: February 2021

While driving a vehicle, perceiving velocity is important for appropriate operation and is one of the most important factors for preventing collisions and traffic congestion. In contexts where perceiving velocity changes is difficult, such as on an undulating road, the velocity may exceed the speed limit or traffic congestion may occur due to heavy braking to avoid a collision. Hence, we proposed a method of modulating the perception of velocity through tactile stimulation to promote adequate operation for the driver. In contrast to methods using visual and auditory stimulation, this method has advantages of not increasing the visual cognitive load, not disturbing the enjoyment of music, and reliably stimulating the driver. In this study, we constructed a velocity perception model based on vibrotactile stimulation induced by the engine speed and proposed a method of changing the vibrotactile stimulation by altering the shift position of the transmission to modulate the perception of velocity without additional vibration actuators, regardless of the actual velocity. We measured the seat and engine vibration using two different vehicles. The results demonstrated that the peak acceleration frequencies are proportional to engine speed, indicating that the vibration depends upon the engine speed, not the velocity. We implemented a method of changing the shift position in an actual vehicle and verified the feasibility of the method through a psychophysical experiment. The results showed that drivers perceived a higher velocity with increasing engine speed and lower velocity with decreasing engine speed.
Study of Neural-Kinematics Architectures for Model-Less Calibration of Industrial Robots
Authors: Tiboni Monica ,   Università degli Studi di Brescia via Branze 38, Brescia 25123, Italy, Legnani Giovanni , Pellegrini Nicola
Published: February 2021

Modeless industrial robot calibration plays an important role in the increasing employment of robots in industry. This approach allows to develop a procedure able to compensate the pose errors without complex parametric model. The paper presents a study aimed at comparing neural-kinematic (N-K) architectures for a modeless non-parametric robotic calibration. A multilayer perceptron feed-forward neural network, trained in a supervised manner with the back-propagation learning technique, is coupled in different modes with the ideal kinematic model of the robot. A comparative performance analysis of different neural-kinematic architectures was executed on a two degrees of freedom SCARA manipulator, for direct and inverse kinematics. Afterward the optimal schemes have been identified and further tested on a three degrees of freedom full SCARA robot and on a Stewart platform. The analysis on simulated data shows that the accuracy of the robot pose can be improved by an order of magnitude after compensation.
Wellbore Strengthening in Narrow Margin Drilling
Authors: Benyeogor Ogochukwu , Awe Sunday , Amah Obinna , Ugochukwu Oseme , Erinle Adeyemi , Akinfolarin Ayodele , Oseme Ugochukwu
Published: February 2021

Natural gas is one of the cleanest energy sources, its uses range from fueling power stations to cooking and heating. Global demand for natural gas is expected to rise in the coming years. Meeting these energy demands means drilling deeper exploration and development wells to access huge volumes of gas present under high pressure and high temperature (HPHT) conditions. Despite the attractiveness of the reward, managing the narrow drilling window between the reservoir pore pressure and the formation fracture gradient has remained a major source of cost escalation and non-productive time on HPHT projects. In order to improve the economics of HPHT projects, technologies like Managed Pressure Drilling and borehole strengthening have been used as a means of mitigating the risks associated with narrow margin drilling, thus enabling a paradigm shift from traditional casing seat selection methodology.

In the Niger Delta, it is not uncommon to observe significant jumps in pore pressure values in proximate high pressure formations. The simplification of well designs and successful drilling operations are often challenged by the need to navigate through series of high pressured reservoirs in narrow margin windows. Compliance with process safety requirements requires selection of mud weight that is low enough to prevent mud loss and high enough to overbalance the reservoir pressure. Mud loss induced by formation fracture is often encountered in tight margin drilling, and when this happens, the focus shifts to strengthening the damaged wellbore using various techniques such as pumping chemical resins to seal off the loss zones. Various degrees of results have been achieved when borehole strengthening techniques are deployed with the objective of restoring wellbore integrity in both permeable and non-permeable formations. Successful deployments have resulted in achieving the well objectives safely and cost effectively.

This paper details loss of wellbore integrity experienced on an HPHT well in the Niger delta and the wellbore strengthening strategy that was used to restore the strength in a non-permeable formation. It sheds light on how understanding the nature of the fracture, rock lithology as well as proper job execution can restore a damaged wellbore to its previous strengths. A Cost reduction approach to the execution of the strategy is also discussed.
Structural Inversion, Reactivation and Extensional Detachment and Their Influence on the Formation and Preservation of Hydrocarbon Accumulations in Northern Western Desert of Egypt
Authors: Sun Ziming
Published: February 2021

The northern Western Desert Basins of Egypt experienced a complex evolutionary history and several transformation of tectonic stress field properties. An integrated analysis of geological and geophysical data reveals that structural inversion, reactivation and extensional detachment develop in the area, and have a significant effect on formation and preservation of hydrocarbon accumulations. Such an analysis is paramount for prospect evaluation, risk mitigation, and therefore improving the exploration success rate.

The rifting in Jurassic and early Cretaceous formed several faulted-depression basins with boundary normal faults in the area. A few boundary normal faults were reactivated in late Cretaceous to Eocene period as reverse faults with dextral compressive features, giving birth to a series of inverted anticlines over them. Compressive wrenching movement on the boundary faults greatly weakened their lateral sealing capacity and accordingly enhanced the vertical conduit capacity of hydrocarbon migration from the Jurassic source kitchen to Cretaceous inverted anticlines along the boundary faults. This is why Cretaceous inverted anticlines show a high concentration of hydrocarbon accumulations whereas there are few oil discoveries in the lower Alam El Bueib (AEB) formation and Jurassic along the boundary faults.

Reactivation of basin boundary normal faults in late Tertiary to present abounds in the area. Most of them are surface penetrating, which are vital to the existing hydrocarbon accumulations because the reactivation could not only make poor the preservation of the existing hydrocarbon accumulations and cause the redistribution of hydrocarbons, but also it would destroy the existing hydrocarbon accumulations. Some unsuccessful wells can be attributed to the reactivation of basin boundary normal faults in late Tertiary to present. Some prospects associated with the reactivation of basin boundary normal faults have the same or similar hydrocarbon preservation risks as the unsuccessful wells.

By integrating seismic interpretation and lithologic assemblage and thickness variation of the AEB formation, an extensional detachment fault was recognized in Alamein Basin. The detachment, located in the mudstone-dominated AEB 5-6 intervals, makes hydrocarbon migration difficult from Jurassic source kitchen to Cretaceous traps because the vertical migration pathways have been cut off by it, and are unfavorable for the formation of hydrocarbon accumulation above it.
Innovations in Carbon (iv) Oxide Capture and Sequestration for Operations, Engineering and Technology
Authors: Lilian Simiyu E. , Konez Sandra
Published: February 2021

Fossil fuel combustion supplies more than 85% of energy for industrial activities and thus it is the main source of greenhouse gases in the form of CO2. This is expected to remain unchanged for a long time as the world energy consumption doubles. Renewable energy is often a better option since it is environmental friendly but its technologies are not financially available for most countries. Carbon (iv)oxide capture and sequestration (CCS) is necessary for meaningful greenhouse gases reduction in the immediate future. CCS could reduce emissions by 19%. This is an important bridge between our lifestyle and an environmental friendly world. The components of CCS system include; capture (separation and compression), transport, injection and finally monitoring.

Power plants which are gas and coal fired are the main source of CO2. Other candidate sources include; cement production plants, refineries, petrochemical industries, oil and gas processing firms and natural gas wells

The methods of capturing CO2 are pre-combustion, post-combustion and oxy-combustion/oxy-fuel.

Possible sequestration places for the captured CO2 include; geological storage, for example depleted oil and gas reservoir, enhanced oil recovery, un-minable coal seams and deep saline formations, ocean storage, mineral carbonation and algal growth. Each of the methods above have their advantages and shortcomings as discussed in the research paper.

CO2 can be utilized in various ways like, conversion into renewable fuels, formic acid, syngas, methane and methanol, utilizing CO2 as a feedstock for organic and inorganic carbonates, urea and biodegradable polymers as well as non-conversion use of CO2 for example as a geothermal fluid, used in enhanced oil recovery and beverage making. The challenges of CCS are; high cost of capture transport and injection, environmental and safety, subsurface uncertainty, legal and regulatory issues. Trappings contribute to storage of CO2 in a site. They include; Structural and stratigraphic, residual, solubility, mineral trappings.

In conclusion, an approach that integrates different methods of capture and storage of CO2 may be a practical solution for CCS.
A Case Study of the Successful Deployment of Tractor Conveyed Perforation in Highly Inclined Well
Authors: Isehunwa Oloruntoba , Eze Joy , Ogunrinde Ademola , Boms Allen Aka
Published: February 2021

Well A is one of the only two wells on the XY reservoir structure providing the optimum drainage point on that reservoir. However, Well X had been shut in due to high sand production and had been flagged as ‘non-integral’ with regards to SPDC Well Integrity Management (WIM) policy due to its faulty Tubing Retrievable Surface Controlled Subsurface Safety Valve (TRSCSSSV). The well was thus scheduled for repairs.

The objective of the workover operation as with most others done in SPDC was to restore integrity of the well, remediate sand control and improve production across the XY reservoir.

On re-entry into the well, a mechanical restriction was met in the high angle section of the well thus impeding access to drain hole. A review of the situation, showed a possible collapse of the lower completions (sand screen) possibly due to high sand production. An attempt at sand clean-up was futile.

This paper describes the unconventional but successful deployment of wireline conveyed perforation gun on tractor in SPDC to perforate this highly deviated well, thus, providing drainage access and recovering 2.14 MMstb of oil and 0.79 BScf of associated gas.

Amongst several options including the use of coiled tubing or wireline as means of perforation, the tractor conveyed guns stood out for a highly inclined well such as Well A. The Well Tractor functions with an electric over hydraulic power relationship and uses its wheel section to push the passenger tool downhole as cable is fed off the electric line unit. The make-up of the tractor conveyed system makes it suitable for high angle wells while providing a cost savings over other systems.
Practical Experience in Rig Move and Workover Operations in an Amphibious Terrain: A Case Study of Escravos Beach Rig Move and Workover Operations
Authors: Eze Joy , Onakomaiya Oluwarotimi , Ogunrinde Ademola , Adegboyega Olusegun , Wopara James , Timibitei Fred , Ideh Matthew
Published: February 2021

The exploration and production of oil and gas mostly occurs in remote locations, so as to minimize human exposure and Health Security Safety and Environment (HSSE) risks. Shell Companies in Nigeria is not any different having operated for over 50 years in Nigeria with the largest footprint of all the international oil and gas companies operating in the country spanning over land, swamp, shallow waters and offshore terrains. Shell Petroleum Development Company, the operator of a joint venture (the SPDC JV) between the government-owned Nigerian National Petroleum Corporation – NNPC (55% share), Shell (30%), Total E&P Nigeria Ltd (10%) and the ENI subsidiary Agip Oil Company Limited (5%) focuses mostly on onshore and shallow water oil and gas production in the Niger Delta with about 60+ producing oil and gas fields and a network of approximately 5,000 kilometers of oil and gas pipelines and flow lines spread across the Niger Delta.

Escravos Beach is over 60km from the closest major city, Warri, a major oil and gas zone in the Niger Delta. It is bounded by the Escravos River to the East, Chevron canal to the North and the Atlantic Ocean to the South and is covered with predominantly mangrove forest especially along the creeks and consists of a number of natural and man-made waterways (rivers, creeks and canals).

Unlike most other onshore operations, this location can only be accessed via the waterways; thus requiring the rig equipment and every other equipment to be channeled via the waterways and subsequently on land to arrive at the site. The amphibious nature of this operation requires a combination of onshore and swamp requirements with increased HSSE exposure, logistics requirement and cost. This paper aims to highlight the practical experience garnered in the rig move and workover operations of Rig XYZ which operated in the Escravos Beach region.
Cost-Effective Directional Drilling and Logging-While-Drilling Operational/Maintenance Model Aids an East Africa Operator to Deliver Its Remote Location Exploration Campaign
Authors: Lunney Iain
Published: February 2021

In a cost-sensitive market driven by depressed commodity prices, significant capital challenges exist for operators interested in pursuing exploration activities in remote environments to define their producible reserves. This paper explores the organizational and operational model developed by a service company over several remote area mobilizations; this model resulted in an optimized low-cost service delivery model characterized by top quartile operational key performance indicators (KPIs). The model centralizes critical functions of an operational organization into discrete service units that are located near the operational location or that provide remote assistance with communication and reporting lines in place to function effectively. Top quartile operational performance and tool availability is a result of placing a remote repair and maintenance facility that includes containerized specialty modules near the operational area. The upfront bottomhole assembly engineering, 24/7 monitoring, and proactive feedback of logged data, drillstring dynamics, and wellbore hydraulics are performed by a core team of subject matter experts in their respective disciplines from an established centralized operating center. The operational KPIs over the course of the six well exploration campaign provided substantial evidence to support the reliability of the model and the high level of experience used in both the remote maintenance facility and the operations center support team.
Novel Well Flow-Control Valve for Flexible Well Completion and Application in Commingled Production of Oil and Gas in West Africa
Authors: Bagal Joseph , Hallaire Maximilien , Hazel Paul
Published: February 2021

This paper presents the development, qualification and field trial of a novel well flow valve that delivers unlimited zonal selectivity in single skin lower completion without the use of control lines. Control lines have limitations and risks due to complexity during deployment, restrictions on the number of zones, complications with liner hanger feed thru and associated wet connects. It is desirable to remove the control lines whilst maintaining the functionality of multi zone, variable choke flow control.

The well flow valve is a full-bore, reliable and robust mechanically operated sleeve, qualified in accordance with ISO14998 including multiple open/close cycles, at a sustained unloading pressure of 1,500 psi, with highly customizable flow ports.

The need for such a solution was identified by an operator in West Africa. The well objective was elevated from a gas producer to a well that required the flexibility to produce gas or oil with gas lift capability. The well flow valve was selected and required on site variable choke capability for both oil and gas production, with choke position verification, ability to handle dirty gas production without risk of plugging, compliant with a high rate and high pressure proppant frac along with ease of operation and long term reliability.

The field trial included a high pressure proppant frac in the oil zone. In the shallower gas zone, three well flow valves were used to deliver variable choking capability from maximum gas flow rate with minimal delta P adjusting down to a choke size suitable for gas lift. The well flow valves were operated using a high expansion shifting key conveyed on eline through the 3 ½" production tubing. The shifting key expanded in the 4 ½" lower completion to open/close individually all the well flow valves in a single trip. Incorporating this new product overcame the challenges presented and met the objective of commingled production of oil and gas. The well flow control valve demonstrated flexibility through design, supply chain, manufacturing, and operations. This paper will also outline the future road map covering further developments of the well flow valve and its incorporation into an enhanced flexible lower liner solution aimed at lowering well completion costs and risks.
The Risk of Stroke after Acute Myocardial Infarction in Patients with and without Atrial fibrillation: A Nationwide Cohort Study in Taiwan
Authors: Chiang Cheng-Hung , Hung Wan-Ting , Huang Wei-Chun , Lin Kun-Chang , Cheng Chin-Chang , Kuo Feng-Yu
Published: February 2021

Background
Both acute myocardial infarction (AMI) and atrial fibrillation (AF) are risks for stroke. The risk of stroke after AMI may be different in patients with or without AF. The aim of this study was to evaluate the impact of AF on stroke in patients after first AMI.
Methods
This is a retrospective nationwide cohort study. A total of 170,472 patients who had the primary diagnosis of first AMI between 2000 and 2012 were enrolled. Among them, 8,530 patients with AF were identified. Propensity score matching technique was used to match 8,530 patients without AF with similar ages and genders. All patients were followed until stroke or 31 December 2012, whichever occurred first. Kaplan–Meier cumulative survival curves were constructed to compare stroke between AMI patients with and without AF.
Results
Overall, 12-year stroke rate was higher in patients with AF than without AF (log rank P-value < 0.001), including in different genders, ages, or intervention subgroups. In patients with AF, those with preexisted AF had higher stroke rates in male gender, age below 65 years, and with intervention subgroups than those with new-onset AF. In Cox proportional-hazard regression analysis, AF was an independent risk factor for stroke after first AMI (hazard ratio, 1.67; 95% confidence interval, 1.5–1.87).
Conclusions
AF significantly increased stroke risks after first AMI. In patients with AF, those with preexisting AF have higher stroke risks in male genders, ages below 65 years, and with interventions than those with new-onset AF.
The C2-symmetry colorimetric dye based on a thiosemicarbazone derivative and its cadmium complex for detecting heavy metal cations (Ni2+, Co2+, Cd2+, and Cu2+) collectively, in DMF
Authors: Hishimone Phillipus N , Hamukwaya Eunike , Uahengo Veikko
Published: February 2021

The field of chemosensing has been experiencing an exponential expansion in recent times, due to increased demands for simpler and user-friendly analytical techniques, in order to combat and confront the challenges of industrial pollutions in the 21 st century. Metal complex-based chemosensors have received little attention while exhibiting excellent sensing properties, comparing to their organic counterparts. Thus, a thiosemicarbazone-based ( H ) and its cadmium complex ( P ) were synthesized, characterized and their photophysical and chemosensing properties were investigated in DMF solvent. The addition of molar equivalents of selected cations (of nitrates or chloride salts) to H and P , produced visually detectable colour changes as well as remarkable spectral shifts. Explicitly, the two probes ( H and P ) were able to collectively discriminate heavy metal cations such as Cd 2+ , Co 2+ , Zn 2+ , Cu 2+ , Ni 2+, and Ag + , both in DMF, among all other heavy metal cations tested. None of the anions could be detected by H or P , even when the tetrabutylammonium salts (TBAs) were used, the action presumably ascribed to the solvent effect. Thus, H and P can be used to selectively and sensitively detect the presence of heavy metal cations, via naked-eye detectable colour changes in an aqueous soluble solvent such as DMF.
Cloning and characterization of the DIR1 promoter from Eucommia ulmoides Oliv and its response to hormonal and abiotic stress.
Authors: Ziyun Li , Biao Li , yichen Zhao , Degang Zhao
Published: February 2021

The lignans of Eucommia ulmoides have been extensively studied and shown to have a dual mechanism of regulating blood pressure. Studies have shown that DIR1 is a key gene in the biosynthetic pathway of lignans in Eucommia ulmoides Oliv. In this study, a 2000 bp upstream promoter sequence was cloned, and part of the sequence (1495 bp) and its 5'-end truncated segment were constructed into the pCAMBIA1391Z expression plasmid upstream of ß-glucuronidase (GUS). Agrobacterium-mediated genetic transformation produced stable transgenic tobacco lines. The results showed that although both full-length and truncated promoters could initiate GUS expression, their levels were influenced by the degree of deletion at the 5' end. GUS histochemical staining showed that the core promoter region was located in the region containing the transcription initiation site (TIS) within 212 bp. In addition, the DIR1 promoter responded to environmental and hormonal stressors, such as jasmonic acid (MeJA), abscisic acid (ABA), D-mannitol (drought mimic), and high concentrations of NaCl. In transgenic tobacco seedlings, MeJA, D-mannitol, and ABA could activate the DIR1 promoter, whereas high concentrations of NaCl could inhibit it. In E. ulmoides Oliv seedlings, MeJA, NaCl, and D-mannitol activated the DIR1 promoter, whereas ABA had an inhibitory effect. In summary, our findings provide a theoretical basis for the use of the DIR1 promoter in plant genetic engineering, indicating its potential. Our study also presents novel insights for lignan biosynthesis and sheds light on the mechanisms of E. ulmoides Oliv in response to stress.
Numerical Design and Frequency Response of all group-IV alloys based MQW Transistor Laser
Authors: Ranjan Ravi , Pareek Prakash , Das Mukul Kumar , Pandey Saurabh Kumar
Published: February 2021

In this work, a theoretical model is developed for n-p-n mid-infrared transistor laser (TL) with strain-balanced Ge0.85Sn0.15 multiple quantum well (MQW) structure in the base. Variation of optical confinement factor, modal gain and threshold current density have been rigorously investigated for different number of QWs (N) in MQW structure. The result shows that overall optical confinement factor and modal gain increase with N. The frequency response of MQWTL for common base (CB) configuration is estimated from small signal relationship between the photon density and emitter current density by solving laser rate equation and continuity equation considering the virtual states as a conversion mechanism. Increment of N causes modulation bandwidth to initially increase and then decreases with N, which reveals a shifting of device nature for higher values of N. The results also suggest that on judicious selection of N, the proposed device can become a viable monolithic light source.
The Effects of Ionotropic GABA Receptor Blockage on Brain in Sepsis-induced Rats
Authors: Ates Gulten , Ozkok Elif , Gundogan Gul Ipek , Tamer Sule
Published: February 2021

Encephalopathy develops following sepsis, which is defined as life-threatening organ failure due to the irregular response of a host to infection. It has high mortality and morbidity rates. In this study, we aimed to investigate the effects of inflammation on brain tissue, and the effects of the GABAA receptor antagonist bicuculline in rats with sepsis. Sepsis was experimentally generated in rats using LPS. The rats were divided into four groups as control, LPS (10 mg/kg i.p.), bicuculline (1.5 mg/kg bicuculline methiodide s.c.), and LPS + bicuculline. Electrophysiologic recordings and body temperature measurements were completed at the 24th hour after injection, and blood samples were taken from the heart for measurements of biochemical parameters. TNF-α, IL-10, and GABA levels were measured using ELISA, and MDA levels were measured using the Bouge method from brain tissue. Tissue imaging was performed with S100-ß, NEUN, and synaptophysin antibody using immunofluorescence staining. One-way ANOVA and the Tukey test were used in statistical analysis. Inflammatory parameters increased in brain tissue in the LPS group compared with the control group. The immunofluorescence staining results in brain tissues were as follows: S-100ß involvement increased, and NeuN and synaptophysin involvement decreased in the LPS group. In electrophysiologic recordings, activity consistent with acute non-focal seizures was observed in the LPS group; however, it was consistent with the resting status in other groups. We suggest that the GABAA antagonist bicuculline methiodide may be a prophylactic agent in sepsis, which caused the impaired neurotransmitter balance, increased pro-inflammatory cytokine and lipid peroxidation, and decreased anti-inflammatory cytokine levels.
Tilt illumination for structured illumination imaging
Authors: Jin Xin , Ding Xuemei , Tan Jiubin , Shen Cheng , Zhou Xuyang , Liu Shutian , Liu Zhengjun
Published: February 2021

To achieve super-resolution imaging, the information in higher frequency of the observed sample is collected by illuminating with a structure beam for a limited optical transfer function (OTF). In this paper, tilt illumination mode is introduced to structured illumination microscopy (SIM) for enhancing lateral resolution. More sample spectrum more than traditional SIM, can be obtained by detector. Thus, SIM with tilt illumination can be improved at the aspect of lateral imaging resolution.
Significance of Glasgow prognostic scores in NSCLC patients treated with immunotherapy after platinum-based cytotoxic chemotherapy
Authors: Kang Hye Seon , Shin Ah Young , Yeo Chang Dong , Kim Sung Kyoung , Park Chan Kwon , Kim Ju Sang , Kim Seung Joon , Lee Sang Haak , Kim Jin Woo
Published: February 2021

Background: The Glasgow prognostic score (GPS) reflects the host’s systemic inflammatory response and is a validated prognostic factor in lung cancer. However, little is known about the prognostic role in non-small cell lung cancer (NSCLC) patients treated with immunotherapy after platinum-based cytotoxic chemotherapy.Methods: This study used a lung cancer cohort of the Catholic Medical Center of Korea between January 2018 and September 2020. We included patients who were diagnosed with unresectable advanced stage NSCLC or recurrent disease after pulmonary resection and had received at least one regimen of platinum-based chemotherapy before the administration of immunotherapy. The prognostic value of the GPS was assessed in patients with NSCLC treated with anti-PD1 or anti-PD-L1 (pembrolizumab, nivolumab, or atezolizumab). The GPS was calculated using C-reactive protein and albumin concentrations within one week before starting anti-PD1 or anti-PD-L1 treatment. Results: A total of 78 patients with NSCLC treated with immunotherapy as second or further-line therapy after platinum-based chemotherapy were included in the study. Kaplan-Meier analysis revealed that higher GPS values were significant predictors of shorter immune-related progression-free survival (irPFS) (log-rank P < 0.001) and overall survival (OS) (log-rank P < 0.001). In the Cox regression multivariate analysis, the hazard ratios for irPFS were 0.249 (95% confidence interval [CI]: 0.084 – 0.739, P = 0.012) for PD-L1 expression ≥ 50% and 9.73 (95% CI: 2.931 – 32.298, P < 0.001) for a GPS of 2 relative to a GPS of 0. Older age (P = 0.033), lower PD-L1 expression (P = 0.036), and higher GPS values (P = 0.007) were independently associated with shorter OS.Conclusions: Higher GPS values were identified as a poor prognostic factor for OS and irPFS in NSCLC patients who received immunotherapy as second or further-line therapy after platinum-based chemotherapy.
Ten-year follow up of cosmetic outcome, overall survival, and disease-free survival in endoscope-assisted partial mastectomy with filling of dead space using absorbable mesh for stage ≤IIA breast cancer: Comparison with conventional conservative method
Authors: Takemoto Nobuyuki , Koyanagi Ai , Yamamoto Hiroshi
Published: February 2021

Background

Data on long-term cosmetic outcome, overall survival, and disease-free survival of endoscope-assisted partial mastectomy (EAPM) for breast cancer are scarce. Thus, we examined these outcomes after a 10-year follow-up period, and compared with conventional conservative method (CCM).
Patients and Methods:

Data on 257 patients with stage ≤ IIA breast cancer who underwent CCM (n = 125) or EAPM (n = 132) were analyzed. Cosmetic outcome at 2, 5, and 10 years was evaluated by 5 criteria (breast retraction assessment, nipple deviation, atrophy, skin change, scar). For overall mortality, breast cancer-specific mortality, and recurrence, the risk by operation method was tested by Log-rank tests.
Results

EAPM performed significantly better than CCM in terms of cosmetic outcomes for location B at 2, 5, and 10 year-follow ups. As for cosmetic outcomes by individual criteria, EAPM had significantly higher proportions of satisfactory results for scar across all follow-up periods, and atrophy at 2-year and 10-year follow-up. There were no significant differences in terms of overall mortality, breast cancer-specific mortality, and recurrence between EAPM and CCM. The rates of patients who experienced local recurrence were similar between CCM and EAPM.
Conclusion

EAPM is better than CCM in terms of long-term cosmetic outcome, especially for location B. As a surgical treatment for breast cancer, EAPM is comparable to CCM in terms of mortality and recurrence.