bluuebunny/crossref_metadata_2025 huggingface dataset:
The harsh microenvironment in early breast cancer selects for a Warburg phenotype
Authors: Damaghi Mehdi , West Jeffrey , Robertson-Tessi Mark , Xu Liping , Ferrall-Fairbanks Meghan C. , Stewart Paul A. , Persi Erez , Fridley Brooke L. , Altrock Philipp M. , Gatenby Robert A. , Sims Peter A. , Anderson Alexander R. A. , Gillies Robert J.
Published: January 2021

Significance

Glucose is converted to energy through “fermentation” or “oxidation.” Generally, if oxygen is available, cells will oxidize glucose to CO
2
because it is more efficient than fermentation, which produces lactic acid. But Warburg noted that cancers ferment glucose at a “remarkable” rate even if O
2
is available! This “Warburg Effect” is still misunderstood because it doesn’t make sense that a cell would ferment glucose when it could get much more energy by oxidizing it. The current paper goes to the heart of this problem by defining the microenvironmental conditions that exist in early cancers that would select for a Warburg Effect. This is important because such cells are much more aggressive and like to lead to cancers that are lethal.
The natural axis of transmitter receptor distribution in the human cerebral cortex
Authors: Goulas Alexandros , Changeux Jean-Pierre , Wagstyl Konrad , Amunts Katrin , Palomero-Gallagher Nicola , Hilgetag Claus C.
Published: January 2021

Significance

Communication between cells in the brain relies on different types of transmitter receptors. Can we uncover organizational principles that harness the diversity of such signatures across the brain? We focus on the human cerebral cortex and demonstrate that the distribution of receptors forms a natural axis that stretches from association to sensory areas. Moreover, traversing this axis entails changes in the diversity, excitability, and mirrored density that reflect a basic division in receptor types, that is, ionotropic and metabotropic receptors. The unraveled principles offer explanatory depth for diverse phenomena and entail concrete, testable predictions.
A simple method to measure DC electric field with space charges
Authors: Zhang Bo , Meng Yongchang , He Jinliang
Published: January 2021

DC partial discharge in gas generates many space charges. Because these charges move with the electric field, change the electric field and accumulate on the surface of sensors, it is difficult to measure the electric field in the space. Based on the relationship between the charge accumulated on the surface of the dielectric in the ion flow field and the applied electric field, this paper proposes a simple method to measure the electric field with space charges using a suspended dielectric as a sensor. By testing the charge accumulated on the suspended dielectric, the applied electric field can be determined. The method is verified and the factors that affect the measurement result are investigated by experiments in a predictable and controllable ion flow field. The results show that when saturation of the accumulation of the space charge on the suspended disc is reached, the total accumulated surface charges are linear with the normal component of the external applied electric field. The ion flow density just affects the speed of the charge accumulation and does not affect the amount of saturated surface charges. The relationship coefficient between the surface charge and the electric field can be obtained through calibration. Unlike other methods that regard the accumulation of charge on the sensor as the key interference, the method in this article just uses the accumulation characteristics of the charge on the sensor, which is simple and feasible.
Focused laser differential interferometer response to shock waves
Authors: Lawson J M , Austin J M
Published: January 2021

The focused laser differential interferometer (FLDI) can be used to measure rapid density fluctuations non-intrusively in high-speed flow applications. Being a non-imaging shearing interferometer, FLDI response can be accurately modeled using a paraxial ray-tracing scheme. We present the details of a new numerical implementation of this scheme, capable of accepting flow-field input from analytical models, computational fluid dynamics (CFD) results, and experimental data. This implementation has previously been validated for static (laminar jet) and dynamic (ultrasound-generated) changes in index of refraction by Lawson et al. In this work, we examine the FLDI response to shock waves propagating at up to Mach 10, in Caltech’s hypervelocity expansion tube. While the timescale and approximate form of the signal can be recovered using a simple inviscid, planar shock model, it is found that the inclusion of viscous shock effects allows an accurate simulation of both the magnitude and detailed shape of the experimental response. This is a further analytical validation of the FLDI model that extends beyond the results of the existing dynamic validation case. The model implementation is then coupled to a CFD code, and predictions reproduce experimental FLDI response to a complex shock-dominated flow-field.
A designed flow-through microsystem for accurate and fast measurement of gas sensors at the ppb level
Authors: Zhang Jingjing , Ning Zhanwu , Zhao Peng , Liu Jinhua , Zhang Yanni , Liu Weijie , Liu Ning , Jia Yiting
Published: January 2021

The characteristic parameters of gas sensors depend highly on the method used to evaluate them. This paper presents a flow-through microsystem for accurate and fast measurement of gas sensors, especially for the sensor with a fast response and high sensitivity at the ppb level. The microsystem consists of four parts, i.e. a dynamic multiple gas handling unit, a test gas preheater, an olive-like test chamber with an inner volume of 4.98 ml and data analysis apparatus. Thereinto, the multiple gas handling unit was constructed to meet the needs of dynamical sensor response tests, and the olive-like test chamber was designed based on the principles of low background interference and fast replacement of ambient conditions, which was optimized by computational fluid dynamics simulation and verified by its airtightness and applicable flow rate range. For a flow rate of 300 ml min−1, it can discern that the replacement time for the chamber ambient gas test was about 1 s. Finally, performance tests for two commercial sensors and one home-made sensor were carried out on this microsystem. The results showed that this system can serve as a means of highly sensitive (ppb level) and fast gas sensor evaluation, and the measured values obtained by this system can be considered to be closer to a sensor’s true values.
Experimental and numerical characterization of a radio-frequency plasma source with a DC-grounded electrode configuration using a quarter-wavelength filter
Authors: Soni Kunal , Moser Lucas , Donkó Zoltán , Hartmann Peter , Korolov Ihor , Antunes Rodrigo , Juhasz Zoltan , Steiner Roland , Marot Laurent , Meyer Ernst
Published: January 2021

We present a combined experimental and numerical investigation of the plasma properties in an asymmetric capacitively coupled radio frequency plasma source using argon discharge. Besides driving the system in the conventional way, which results in a high negative self-bias voltage

V

DC

due to the asymmetric configuration, we also connect a ‘quarter-wavelength filter’ to the powered electrode, which lifts its DC potential to zero. At the powered side of the plasma, we employ electrodes with conducting and insulating surfaces, as well as electrodes combining both in different proportions (‘hybrid electrodes’). Measurements are carried out for the plasma potential, the electron density and temperature in the bulk plasma, as well as for the flux-energy distribution of the ions at the grounded surface of the system. The nature of the surface of the powered electrode as well as the presence of the quarter-wavelength filter are found to highly influence the plasma potential,

V

p

‾

. For the electrode with a conducting surface

V

p

‾

∼

20 V and ∼150 V are found in the absence and the presence of the filter, respectively. For the electrode with an insulating surface, the self-bias voltage builds up directly at the plasma interface, thus the filter has no effect and a plasma potential of ∼20 V is found. For the electrodes with different conducting/insulating proportions of their surface,

V

p

‾

ranges between the above values. Particle-in-Cell/Monte Carlo Collisions calculations for identical conditions with hybrid electrodes predict double-peaked ion energy distribution at the powered electrode with peaks corresponding to

e

V

p

‾

and

e
(

V

p

‾

−

V

DC

)

along with a lowering of the plasma potential (whencompared to wholly conducting electrode), a trend that is observed experimentally. These studies are of great importance for the application of similar plasma sources with in-situ cleaning of mirrors in fusion devices and the results can be extended to a variety of plasma processing applications.
Soliton trains after interaction quenches in Bose mixtures
Authors: Cidrim André , Salasnich Luca , Macrì Tommaso
Published: January 2021

We investigate the quench dynamics of a two-component Bose mixture and study the onset of modulational instability, which leads the system far from equilibrium. Analogous to the single-component counterpart, this phenomenon results in the creation of trains of bright solitons. We provide an analytical estimate of the number of solitons at long times after the quench for each of the two components based on the most unstable mode of the Bogoliubov spectrum, which agrees well with our simulations for quenches to the weak attractive regime when the two components possess equal intraspecies interactions and loss rates. We also explain the significantly different soliton dynamics in a realistic experimental homonuclear potassium mixture in terms of different intraspecies interaction and loss rates. We investigate the quench dynamics of the particle number of each component estimating the characteristic time for the appearance of modulational instability for a variety of interaction strengths and loss rates. Finally we evaluate the influence of the beyond-mean-field contribution, which is crucial for the ground-state properties of the mixture, in the quench dynamics for both the evolution of the particle number and the radial width of the mixture. In particular, even for quenches to strongly attractive effective interactions we do not observe the dynamical formation of solitonic droplets.
Potential Applications of Big Data for Managing the COVID-19 Pandemic
Authors: Pradana A R , Madjid S R , Prayitno H J , Utami R D , Dharmawan Y
Published: January 2021

COVID-19 caused by SARS-CoV-2 is being global pandemic which the number of positive confirmed cases and deaths increase massively and rapidly. Big data is a technology can be used for analysing the trend pattern of coronavirus and prevent the spreading of it. Few countries already use big data as a strategy in managing the ongoing of COVID-19 pandemic. This research uses descriptive analytical research to describe the findings of previous research information with a simplified approach. The aim of this research is knowing how big data used for managing the outbreak of COVID-19 by detecting cases, predicting cases and tracking contact through the use of various data characteristics in some countries around the world. Several countries that have used big data to help manage COVID-19 pandemic are Taiwan, China, Korea, Australia. Taiwan uses credit card and geographic route for tracking the routes of tourists, China uses Baidu Maps Traffic Flow as local maps for knowing distribution of aircraft passenger who have potential high risk to get infected by COVID-19, Korea uses insurance data from Korean National Health Insurance Service for knowing the community with hypertension history who have protentional high risk to get infected by COVID-19 and Australia uses application COVIDSafe for handling the spreading by detecting ambient contact. The ongoing of COVID-19 pandemic in the world has caused the big data technology to be considered to be applied in a country so it hopes can reduce the negative impacts caused in several fields.
Mathematical creative thinking ability and problem centered learning
Authors: Desmayanasari D , Hardianti D , Machromah I U , Rohaeti T , Arsisari A
Published: January 2021

This research aims to determine the improvement of students’ mathematical creative thinking ability through Problem Centered Learning (PCL) approach. This research is a quasi-experimental with a non-equivalent research design. The population of this research were the eighth-grade students of SMP Negeri in Bandung. The sample of this research was determined by purposive sampling. The sample consisted of 62 students who were divided into two classes, experimental class and control class. The experimental class uses the PCL approach, while the control class uses conventional learning. Each class consists of 31 students. The data of students’ mathematical creative thinking ability were obtained by using test techniques. The improvement was proven by n-gain value of students’ pre-test and post-test. The conclusions obtained from the data analysis and discussion, there is a significant difference in the improvement mathematical creative thinking ability between high EMA in the PCL group and medium EMA in conventional learning. Based on EMA, PCL can be applied in high EMA classes. While students with medium and low EMA need further research so that students’ mathematical abilities can be improved by PCL.
Improving The Quality of Mathematics Learning Based On Society’s Potency in Junior High School
Authors: Nur Hafida Siti Hadiyati , Santoso  , Sutama  , Nurhidayat  , Dalman  , Hesti  , Kusumaningtyas Dian Artha
Published: January 2021

The objectives of this study were to describe the society’s empowerment in improving the quality of the learning media, learning process, and learning assessment in school. This research applied qualitative with ethnography research design. The data were collected by in-depth interview, observation, and documentation; while the data analysis technique used was the interactive analysis. The results of the study showed the following conclusions. (1) In order to gain good quality learning, it is a must to prepare a good learning media. The minimum component in developing the learning media (syllabus and lesson plan) must content the learning objectives, learning material, study source, and learning assessment. (2) The learning process must use various ways to encourage students’ interest and curiosity, including using various methods, using language styles that are not monotonous, asking questions that guide students’ creativity, using multi-method and multimedia, and giving assignments individually and in groups to students. (3) The assessment becomes a very important thing to determine the level of success in the learning that has been done.
Computational Thinking Lesson in Improving Digital Literacy for Rural Area Children via CS Unplugged
Authors: Yuliana Irma , Hermawan Hardika Dwi , Prayitno Harun Joko , Ratih Koesomo , Adhantoro Muhammad Syahriandi , Hidayati Herlina , Ibrahim Mohd Hairy
Published: January 2021

The advantage of computational tools over human brains is the speed, but the initiative ability of human brains is not owned by computational tools. The perfect combination of thinking and computing lays the foundation of science and gives birth to a series of achievements in technology. The introduction of technology through the subjects of Information and Communication Technology (ICT) in schools nowadays is just limited to using the applications. Computational thinking gives knowledge that builds structural thinking, critical power, and creativity by learning the computing process itself. These are what people need to enhance digital literacy. The way to learn it could be in many strategies. CS Unplugged was used in this research to deliver computational thinking in a simple way related to minimum infrastructure in the remote area for the children at elementary schools. Some activities were done as kinaesthetic learning in certain topics of CS Unplugged. This kind of method does not need some computer devices to get children closer to computer science. A challenge was given to assess the ability of ICT learning which is computational thinking. The children show their enthusiasm for learning, proved by their final score in a challenge. The children’s score significantly improved in learning ICT by using CS Unplugged.
Development of Learning Media Using Android-Based Articulate Storyline Software for Teaching Algebra in Junior High School
Authors: Arum Nissa Amanda Dinda , Toyib Muhamad , Sutarni Sri , Akip Erwin , Kadir Surni , Ahmad  , Solikin Asep
Published: January 2021

Mathematics is a science that deals with the study of abstract forms so that it requires objects or visual aids to concretize them to become more tangible and clear. Science and technology has developed rapidly in education, one of which is an android-based learning media. The purpose of this study was to develop an Android-based learning media on mathematics specifically in the form of algebraic for students in grade VII of SMP Negeri 2 Kartasura. Furthermore, after the development, the validity and feasibility tests were conducted by media experts, material experts, learning practitioners and students. This research conducted by Research and Development (R&D) method. In its development, 6 stages must be passed namely the analysis phase, the planning phase, the development phase, the verification phase, the validation phase, and the final phase with the learning media called OBAR. The developed media was feasible with the result of validation from media experts obtaining an average score of 3.94, was valid. The result of the validation from material experts obtained an average score of 4.5, was very valid. The results of validation by learning practitioners obtained an average score of 4.2, was valid. Moreover, the validation of the students’ responses obtained an average score of 4.54, was most feasible category.
Visual, Auditory, and Kinesthetic Students: How They Solve PISA-Oriented Mathematics Problems?
Authors: Ishartono Naufal , Faiziyah Nuqthy , Sutarni Sri , Putri Amalia Budiana , Fatmasari Lina W S , Sayuti Muh , Rahmaniati Rita , Yunus Melor Md
Published: January 2021

Mathematical problems are given to students to train themselves in their thinking skills and to find out the level of thinking that each student has. Mathematical problem solving is influenced by the level of students’ thinking ability. The purpose of this study was to analyze students’ high-order thinking skills in solving PISA-oriented math problems in terms of learning styles. This type of research is a mix method with a Concurrent Triangulation Strategy design. The population of all students of class X SMA Negeri 2 Surakarta samples in the study of several students in the population. The sampling technique used purposive sampling. Data collection techniques using interviews, documentation, and tests. The results of the study: 1) There was no difference in ability between students’ visual, auditory and kinesthetic learning styles in solving PISA-oriented math problems. 2) There are 23 students who have a visual learning style or 70% of the population. 30% of them are in the high category, 44% are in the medium category, and 26% are in the low category. 3) There are 8 students who have an auditory learning style or 24% of the population. 62.5% of them are in the medium category, and 37.5% are in the low category. 4) There are 2 students who have a kinesthetic learning style, the two students are one in the medium category and one in the low category. In general, each visual auditory and kinesthetic student has the ability to analyze, evaluate, and create as part of the higher order thinking component. However, each of them has a weakness in these abilities.
Metacognitions of Senior High Students in Solving Mathematics Problems
Authors: Narimo Sabar , Sutama  , Prayitno Harun Joko , Fuadi Djalal , Novitasari Meggy , Setiawan Oki , Handayani Tri Kinasih , Rahim Fauziah Abdul
Published: January 2021

This is an ethnographic qualitative research of which three main objectives are to describe the 1) advanced, 2) intermediate, and 3) low metacognition levels in solving mathematics problem. In conducting the research, purposive sampling technique was used to determine the research subjects that were the students (i.e. the students with advanced, intermediate, and low metacognition levels) of X IPA 3 class of SMA Negeri 2 Surakarta. The data were collected through observations, documentations, and interviews in which the data validity was measured using triangulation between the sources and the methods used. Afterwards, the data were analyzed inductively. The results of this research suggested that: 1) students with advanced metacognition level are able to perform all the characteristics of awareness aspect in indicator A1, three characteristics of evaluation aspect of indicator E1, and two characteristics of regulation aspect in indicator R1, 2) students with intermediate metacognition level are able to perform four characteristics of awareness aspect in A1, two characteristics of evaluation aspect in E1 indicator, and two characteristics of regulation aspect in R1, 3) students with low metacognition level are able to perform two characteristics of awareness aspect in A1, two characteristics of evaluation aspects in E1, and one characteristic of regulation aspect in R1.
Determinant Factors of Responsibilities and its Impact on Mathematics Learning Outcome of Junior High School Students
Authors: Sutama  , Nur Hafida Siti Hadiyati , Prayitno Harun Joko , Machromah Isnaeni Umi , Kusuma Nadia Trisha , Nurhidayat  , Fatchurahman M.
Published: January 2021

The purpose of this article is twofold: 1) Testing the communication support and organizational culture for learning outcomes in Mathematics indirectly through learning responsibilities, 2) Testing communication support, and organizational culture for learning responsibilities. The research type is correlational quantitative. The study population was 267 students of SMP Negeri 2 Kartasura, Sukoharjo, in 2019/2020. A sample of 160 students was determined by the Slovin formula. Sampling was done by proportional random sampling by lottery. Data collection techniques were carried out with documentation and a closed questionnaire. Data analysis techniques employed path analysis. The results of the study revealed that 1) there was no communication support, school organizational culture, and learning responsibility jointly for mathematics learning outcomes with α = 0.05. Partially, communication, organizational culture, and responsibility significantly supported direct learning outcomes in mathematics. 2) Communication and organizational culture simultaneously supported learning responsibilities with α = 0.05. The amount of communication support and organizational culture simultaneously towards learning responsibilities was 4.9%. Communication support for learning responsibilities was 2.0164%. Besides, organizational culture support for learning responsibilities was 2.56%.
Research High Temperature Characteristics of 4.5kV New Power Semiconductor Device with Wave-based RC-GCT Structure
Authors: Zhao Bo , Luo Xianghua , Tang Chuan , Song Qingchao , Lu Lifu , Xu Baobo
Published: January 2021

In this paper, the effect of temperature change on the static and dynamic characteristics of power semiconductor devices is simulated by ISE-TCAD software with 4.5 kV power semiconductor device wavy base regions RC-GCT. the results show that the forward voltage drop UF of the device increases with the increase of temperature at high current density, the forward opening and turning off time of the device becomes longer, and the trailing current increases. The results of this study have certain reference value for the design and development of IGCT for new power semiconductor devices.
A Hybrid LED Sink Driver Combining a Buck-Boost Converter and a Switched-Capacitor Step-Up Converter with Nested Topology
Authors: Eguchi K , Shibata A , Do W , Asadi F
Published: January 2021

For LED lighting applications, this paper presents a novel light emitting diode (LED) sink driver with high voltage gains. Unlike traditional LED sink drivers, the proposed LED sink driver consists of a buck-boost converter and a switched-capacitor (SC) step-up converter with nested topology, where an input voltage is converted twice by cascading these two converter blocks. Therefore, the proposed hybrid topology enables the LED sink driver to achieve not only flexible control of an output voltage but also high voltage gains and few passive components. The characteristics of the proposed LED sink driver are investigated by theoretical analysis, simulation program with integrated circuit emphasis (SPICE) simulations, and breadboard experiments. In the performed simulations, the power efficiency of the proposed driver reaches about 80 % at 500 mW when the duty factor is 0.5. Furthermore, the experiment demonstrates high voltage gains and flexible controllability of an output voltage.
Research and Development Scheme of Zero Line Live Fault Device for Low Voltage Overhead Line
Authors: Zhenyu Mao , Hongzhi Zhou , Hui Huang , Ming Tang
Published: January 2021

In order to reduce the frequency of zero line live faults on overhead lines in low-voltage stations and shorten the time for maintenance and repair when zero line live faults occur, the existing zero line live fault repair methods are summarized, and the Preventive measures, and proposed a fast fixed-point device research scheme for the live line zero line live fault of low-voltage overhead lines. The simulation criterion of live line live fault of the zero line is studied with the help of simulation software such as ATP-EMTP. Live fault type identification model to improve the accuracy of fault type diagnosis. It is expected that the location of the zero line live fault can be located in a shorter time. This solution will greatly reduce the manpower and material input during the live line maintenance work. Maintenance time has engineering transformation value.
Ultra-Low Power Current Reference Based on Flat Band Difference of MOSFETs
Authors: Shinde Suhas Vishwasrao
Published: January 2021

In this paper, an ultra-low power MOS current reference circuit is presented. It is based on the flat band voltage difference of oppositely doped polysilicon gate MOSFETs which are operated in weak inversion. It describes a method to achieve zero temperature coefficient of reference current at target temperature. Simulation results show 20nA reference current with temperature drift of 165ppm/°C. Simulated 3σ monte carlo process and mismatch variation of current is 11.2nA. After trimming it is reduced to 808pA. Typical quiescent current is 22.5nA at 3.75V nominal supply voltage.
An alternative ex vivo method to evaluate the osseointegration of Ti–6Al–4V alloy also combined with collagen
Authors: Veronesi Francesca , Torricelli Paola , Martini Lucia , Tschon Matilde , Giavaresi Gianluca , Bellini Davide , Casagranda Veronica , Alemani Fabio , Fini Milena
Published: January 2021

Due to the increasing number of orthopedic implantation surgery and advancements in biomaterial manufacturing, chemistry and topography, there is an increasing need of reliable and rapid methods for the preclinical investigation of osseointegration and bone ingrowth. Implant surface composition and topography increase osteogenicity, osteoinductivity, osteoconductivity and osseointegration of a prosthesis. Among the biomaterials used to manufacture an orthopedic prosthesis, titanium alloy (Ti–6Al–4V) is the most used. Type I collagen (COLL I) induces cell function, adhesion, differentiation and bone extracellular matrix component secretion and it is reported to improve osseointegration if immobilized on the alloy surface. The aim of the present study was to evaluate the feasibility of an alternative ex vivo model, developed by culturing rabbit cortical bone segments with Ti–6Al–4V alloy cylinders (Ti-POR), fabricated through the process of electron beam melting (EBM), to evaluate osseointegration. In addition, a comparison was made with Ti-POR coated with COLL I (Ti-POR-COLL) to evaluate osseointegration in terms of bone-to-implant contact (BIC) and new bone formation (nBAr/TAr) at 30, 60 and 90 d of culture. After 30 and 60 d of culture, BIC and nBAr/TAr resulted significantly higher in Ti-POR-COLL implants than in Ti-POR. No differences have been found at 90 d of culture. With the developed model it was possible to distinguish the biomaterial properties and behavior. This study defined and confirmed for the first time the validity of the alternative ex vivo method to evaluate osseointegration and that COLL I improves osseointegration and bone growth of Ti–6Al–4V fabricated through EBM.
Increasing lifetime maximum intensity of rapidly intensifying tropical cyclones over the western North Pacific
Authors: Song Jinjie , Klotzbach Philip J , Duan Yihong
Published: January 2021

The long-term trend in the annual mean lifetime maximum intensity (LMI) of rapidly intensifying tropical cyclones (RI-TCs) over the western North Pacific (WNP) is investigated in this study. During 1970–2019, a notable upward trend is observed in the average RI-TC LMI, which is primarily linked to a significant increase in the mean intensification rate prior to LMI. This intensification rate increase is caused by an increase in the mean magnitude of RI cases. By contrast there is no significant change in the RI ratio, which is calculated as the proportion of 24 h RI records to all 24 h records before a RI-TC reaches its LMI. Furthermore, there is a significantly greater RI magnitude west of 155° E, where the vast majority of RI cases occur on average. Over this region, there are significant increases in sea surface temperatures, TC heat potential, 700–500 hPa relative humidity and 200 hPa divergence during 1970–2019. Only a small region of significantly reduced 850–200 hPa vertical wind shear is observed to the northeast of the Philippines from 1970–2019. These results imply that both thermodynamic and dynamic variables play an important role in modulating RI magnitude over the WNP.
The continuous spontaneous localization layering effect from a lattice perspective
Authors: Adler Stephen L , Bassi Angelo , Carlesso Matteo
Published: January 2021

For a solid lattice, we rederive the continuous spontaneous localization (CSL) noise total energy gain of a test mass starting from a Lindblad formulation, and from a similar starting point rederive the geometry factor governing center of mass energy gain. We then suggest that the geometry factor can be used as a way to distinguish between low temperature cantilever motion saturation arising from CSL noise, and saturation arising from thermal leakage.
CHINESE, PAKISTANI AND INDIAN POLICY IN THE ARCTIC AND RUSSIAN STANCE
Authors: Krasnozhenova E E , Kulik S V , Pronina V , Yu Eidemiller K , Karabushenko P L
Published: January 2021

The article is dedicated to outlining possible ways of extending Russian presence in the Arctic through cooperation with the Asian emerging economies (namely China, India and Pakistan). In the first part Beijing, Delhi, Islamabad ambitions in the circumpolar north are analyzed. For more comprehensive analysis the insight into tensions withing China-India-Pakistan triangle is given. In the second part the author demonstrates existing formats of Russian cooperation with China and India (both bilateral and multilateral ones). The scheme of establishing mutually beneficial Moscow-Beijing cooperation, based on both sides` advantages and weaknesses, is elaborated.
Environmental control: from inertia of the standard biomonitoring to speed of the online one
Authors: Gudimov A V , Komarova E P
Published: January 2021

Standard biomonitoring system based on sampling technology is not capable of efficient environmental control and ecosystem protection from anthropogenic impacts and followed degradation because of its extremely delayed response to any environmental changes and pollution first of all. Contemporary approach to ecological biomonitoring turns to on-line control of environmental safety. New online technologies and systems of ecological control based on monitoring of the activity parameters in some species-biosensors have been intensively introduced in many countries since 90s as biological early warning systems (BEWS) such as Musselmonitor. The next step is the development of up-to-date technology from simple BEWS to online biosensor monitoring (OBM) in natural ecosystems as a promising tool for immediate detecting of environmental changes and aquatic toxicity in particular. The first technology of online ecological monitoring has been developed in MMBI (1985-2016) from basic to applied research. It was established, that to obtain the reliable OBM technology the background behavior must be properly investigated for long time prior to online-biomonitoring implementation in the field. Nowadays the main task for online biosensor monitoring is the bioindication technology for recognizing of any harm pollution effects online in any time span.
Obtaining carbohydrate biopolymers (prebiotics) from brown algae
Authors: Sokolan N I , Kuranova L K
Published: January 2021

The article discusses the issues of obtaining prebiotic food additives - an actual area of research in modern food technology. The test results determined the safety of the brown algae Ascophyllum nodosum and Fucus vesiculos growing on the littoral of the Barents Sea. Fucus algae contain significant the amount of alginic acid in terms of absolutely dry weight (a.d.w.) which proves the possibility of using them as raw materials for the production of sodium alginate. It was shown in the work that it is preferable to use Fucus vesiculosus for this purpose, since the content of alginic acid in it and the yield of finished products are higher. Studies of frozen algae in storage revealed a significant loss of water even after a month of storage of raw materials, while during storage of dried algae, the qualitative composition of the product remains constant. The properties of sodium alginate samples obtained from different types of fucus algae were studied. It was found that sodium alginates in appearance represent a free-flowing substance in the form of small thin plates, from light to dark brown in color, without taste and odor. Fucus sodium alginate can be used as a prebiotic, since it is a highly viscous biopolymer and belongs to natural dietary fiber.
Problems and perspectives of the ineffective gold-bearing deposits development
Authors: Latysheva M A
Published: January 2021

This article discusses the problems and prospects of mining placer gold not only in the Trans-Baikal Territory but also in Russia as a whole. The reduction of reserves in placers and a decrease in the quality of minerals in them open up new prospects for the extraction of this precious metal. The ineffective placers, of which, according to preliminary estimates, there are approximately 600 in the Trans-Baikal Territory, can become promising objects in gold mining. However, there are some negative factors that will complicate the gold mining operations. The mining of alluvial gold, even with the best existing technologies, remains a sector of high environmental risk; in many settlements, a gradual decrease in the population and the “extinction” of settlements is predicted, whereas illegal gold mining is gaining traction. Neither the regional nor the federal institutions of environmental supervision are now able to resist the destruction and degradation of nature from the mining of placer gold. In general, this leads to an increase in the negative impact of alluvial gold mining on natural systems and the socioeconomic sustainable development of the regions and municipalities, in which this type of activity is carried out, as well as an increase in accumulated environmental damage. The presented organizational and economic mechanism for the development of ineffective placers will contribute to solving the problems observed in the industry and will allow the implementation of measures proposed by public persons.
Defining the rate of air emissions fee
Authors: Ivanova M P , Tagaeva T O
Published: January 2021

Industrial production disturbs the balance of an already delicate environment, and there is a negative impact on the microclimate in the area that is imposed due to cross-regional pollution. The essence of the problem is the movement of hazardous air pollutants throughout the atmosphere over the long distances, and the issue of government control over the air emissions acquires cross-regional significance. Additionally, particular attention should be paid to the question of payment for air emissions. Today, the economic instruments to reduce the negative environmental impact and to ensure compliance with the environmental regulations are only partially applied. All mentioned above underline the need for consideration of the given problem, which can be solved by the additinal method. Therefore, the authors of the present paper suggest a method to define the rate of air emissions fee (currently there are no rates applied). Besides, it should be stressed that this method would allow for effective calculation of payments for harmful pollutant discharge into air. The research outcomes can be used to further develop environmental regulations.
The transformation and dynamics of land resources in the Trans-Baikal Territory
Authors: Pomazkova N V , Faleychik L M
Published: January 2021

We investigated the structure of land resources in the Trans-Baikal Territory and considered the dynamics of various land categories from 2000 to 2019. There are no significant shifts in the distribution of land between land users. Over the past decades, there has been an increase in the lands of specially protected natural areas and the forest lands at the expense of agricultural lands and land reserve. The total area of agricultural land is 7,985.8 thousand hectares or 18.5% of the region’s area. The results of the analysis allow us to conclude that in the Trans-Baikal Territory, the possibilities for a significant increase in arable land are very limited. According to our estimates, approximately 65% of the area in the region is elevated areas, and 67.1% of the area is slope areas. Moreover, most areas in the municipal districts can be classified as zones with erosion-prone conditions for agriculture. The analysis of the land resources in the Trans-Baikal Territory using geoinformation technologies revealed the terrain features of the municipal districts in the context of the slopes. The existing economic and environmental risks of land involved in the industrial and agricultural production require a transition to adaptive landscape land-use systems.
Professional training future geography teachers
Authors: Tyunkova I A
Published: January 2021

The article presents the experience of geography teachers’ training at the Pedagogical Institute of Irkutsk State University. We considered the fields of concern and activities that contribute to the effective formation of methodological and professional skills. It was revealed that the diverse extracurricular activities in geography, carried out in the interaction of the pedagogical university with public organizations, municipal information and methodological center and schools, is effective for the development of creative abilities of future teachers. The engagement of students in the created information and education space directly affects the result of the educational process, develops the ability to solve professional issues. Practical knowledge in the development and implementation of joint cultural and educational activities to popularize geography allows students to apply their experience and skills. Hands-on experience with advanced teachers of geography of the city and region, participation in scientific and practical conferences and methodological seminars makes it possible to form a stable motivation of graduates to pursue a master‘s degree and improve their professional qualifications. This practice allows mastering and using basic scientific and theoretical knowledge and practical skills in professional activities, is one of the mechanisms for managing education quality in training competitive specialists.
Quality of life as a dominant of increasing life security in the region (as exemplified by Irkutsk oblast)
Authors: Veselova V N
Published: January 2021

Assessment relevance of the social security of population in situation of low standards of living and life quality is of paramount importance. The article examines the quality of life of the population as a dominant of increasing the social security of the region. We analyzed the quality of life according to the main living environments of the population and the parameters of its public health as exemplified by Irkutsk oblast for 2005 and 2018. All heterogeneous indicators are given in one measurement system – a rating, where the positions of Irkutsk oblast are determined in comparison with other constituent entities of the Russian Federation and regional trends are identified. The method of indicative analysis was used as an additional method. The assessment showed that the main macroeconomic indicators the region is in the top twenty ratings of leading regions among the subjects of the Russian Federation over the period under review. By the main parameters of the living standards Irkutsk oblast significantly worsened its position by 2018 and entered the top twenty outsider regions. By the level of environmental pollution, the region also belongs to the outsider regions, consistently occupying the last places in the rating. The cumulative impact of environmental quality is reflected in low level of public health. Within the framework of social security of population, we identified several threats: high level of poverty and unemployment, morbidity and mortality.
Vegetation features of the Olkha tableland
Authors: Korolkova E E
Published: January 2021

The vegetation of the Olkha tableland is located on the border of the Central Siberian subtaiga light-coniferous and South Siberian mountain-taiga dark-coniferous plant forms. The interpenetration of elements of these two large plant coenotypes leads to an increase in the flora-cenotic diversity and is of particular scientific interest. Currently, the entire territory of the tableland is included in the zone of active forestry use, which leads to serious disturbances and complete destruction of plant communities. Using the method of geobotanical mapping, a detailed study of the structure and dynamics of extension, an assessment of the disturbance was carried out, and the flora-cenotic diversity was revealed. Thanks to cartographic visualization, it can be seen that the distribution of plant communities in the territory is 50% subordinate to the altitudinal-belt subordinates. Microclimatic conditions play a great role in the change in the structure of indigenous vegetation, reflecting the features of the topography. Potentially, the territory is characterized by a predominance of dark coniferous and mixed dark coniferous-light coniferous forest communities. Approximately 15% of the territory is occupied by bog plant communities. There are also stone runs, stony placers, and rocky outliers uncovered by closed plant communities. Almost 76% of the vegetation of the plateau is represented by secondary (disturbed) small-leaved and coniferous-small-leaved forests, which are the result of active forest industrial use.
Where are the North Atlantic fish going, and where should fishermen go?
Authors: Li Chengxin , Zhao Liangchen , Li Dongyun , Chang Chenyang , Chen Jiakai , Jiang Chenlu
Published: January 2021

On September 23, 2019, the World Meteorological Organization WMO published the Global Climate Report 2015-2019, which explained the trend of global warming. The phenomenon of rising global ocean temperature in the report is also an issue that needs to be researched. It will make certain marine life be forced to migrate from their habitats, thus affecting the development of economic industries such as fisheries. As consultants to the Scottish North Atlantic Fisheries Management Association, in this work, we have launched a corresponding study on this issue. Corresponding mathematical models have been established, which can well predict the future distribution of fish populations. Questions are essentially predictions of the future distribution of North Atlantic fish stocks and their impact on fishing companies. So our first task is to build an identification and prediction model of future fish habitat space model (IPM-FFHS Model). Because this distribution is caused by changes in ocean temperature, we have established a prediction model for the average sea surface temperature of the North Atlantic region (AMO-BP Model) based on BP neural network to predict future SST. At the same time, other influential factors of the distribution can modify the model. The AMO-BP Model was then combined with the current distribution of the habitat of the fish to draw a predicted spatial image of the future habitat range. At last, we combined the IPM-FFHS Model to obtain the abandonment temperature threshold of the fishery to obtain the duration of fish migration and the survival environment under different effects.
Sensitivity Study on Influencing Factors of Coupled Motion Characteristics for Truss Spar
Authors: Shen Wenjun , Tan Zhonghua , Hu Chuanqi
Published: January 2021

In the absence of mooring condition, the heave and pitch coupled equations are established considering the effect of static stability and wave surface elevation for a truss spar platform. The influence of the change of the pitch period and the external excitation force (combined wave loads and wind loads together) on the stability of the heave-pitch coupling motion is studied by means of numerical iteration method. The results show that when the wave frequency is close to the natural heave frequency besides the heave-pitch frequency ratio is close to 2: 1, both of the amplitude of heave and pitch motion are increased considering the wind loads. It is about 12 percent increase for heave motion, while 8 percent for pitch motion. Meanwhile, there is a penetration phenomenon between heave and pitch. And the wind load play a more important role in pitch motion, the characteristic frequency of pitch motion will have an obvious change between 1/2 times sub harmonic motion frequency component and 1 time forced motion frequency component considering the wind load.
Technologies on Safe Construction Ventilation of Long-large Shield Tunnel with Low Gas in Metro
Authors: Zhao Wei , Meng Qingming , Liu Qi , Zhang Mengheng , Li Wei
Published: January 2021

Taking the project of long-large shield tunnel with low gas in Xingtian section of Chengdu Metro Line 18 as an example, A new construction ventilation method is established, which includes: the main tunnel ventilation with axial fans installed at the entrance of the tunnel and the local ventilation with jet fans installed in the shield and at the upper part of the bridge and the top of the 4# trailer for the rear supporting system; the connecting passage ventilation with a jet fan installed on the wall; the crossing ventilation with a jet fan installed in the middle of tunnel. The ventilation technology for safe construction of Metro long-large shield tunnel with low gas is established after detailed calculation of the fan selection, which is applied to finish safely and quickly construction task, and which provides reference for similar projects in the future.