bluuebunny/crossref_metadata_2025 huggingface dataset:
Conservation laws of the complex short pulse equation and coupled complex short pulse equations
Authors: Zhang Lihua , Shen Bo , Han Shuxin , Wang Gangwei , Wang Lingshu
Published: May 2022

In this paper, the complex short pulse equation and the coupled complex short pulse equations that can describe the ultra-short pulse propagation in optical fibers are investigated. The two complex nonlinear models are turned into multi-component real models by proper transformations. Lie symmetries are obtained via the classical Lie group method, and the results for the coupled complex short pulse equations contain the existing results as particular cases. Based on the linearizing operator and adjoint linearizing operator for the two real systems, adjoint symmetries can be obtained. Explicit conservation laws are constructed using the symmetry/adjoint symmetry pair (SA) method. Relationships between the nonlinear self-adjointness method and the SA method are investigated.
Enhancement of charging performance of quantum battery via quantum coherence of bath
Authors: Yu Wen-Li , Zhang Yun , Li Hai , Wei Guang-Fen , Han Li-Ping , Tian Feng , Zou Jian
Published: May 2022

An open quantum battery (QB) model of a single qubit system charging in a coherent auxiliary bath (CAB) consisting of a series of independent coherent ancillae is considered. According to the collision charging protocol we derive a quantum master equation and obtain the analytical solution of QB in a steady state. We find that the full charging capacity (or the maximal extractable work (MEW)) of QB, in the weak QB-ancilla coupling limit, is positively correlated with the coherence magnitude of ancilla. Combining with the numerical simulations we compare with the charging properties of QB at finite coupling strength, such as the MEW, average charging power and the charging efficiency, when considering the bath to be a thermal auxiliary bath (TAB) and a CAB, respectively. We find that when the QB with CAB, in the weak coupling regime, is in fully charging, both its capacity and charging efficiency can go beyond its classical counterpart, and they increase with the increase of coherence magnitude of ancilla. In addition, the MEW of QB in the regime of relative strong coupling and strong coherent magnitude shows the oscillatory behavior with the charging time increasing, and the first peak value can even be larger than the full charging MEW of QB. This also leads to a much larger average charging power than that of QB with TAB in a short-time charging process. These features suggest that with the help of quantum coherence of CAB it becomes feasible to switch the charging schemes between the long-time slow charging protocol with large capacity and high efficiency and the short-time rapid charging protocol with highly charging power only by adjusting the coupling strength of QB-ancilla. This work clearly demonstrates that the quantum coherence of bath can not only serve as the role of “fuel” of QB to be utilized to improve the QB’s charging performance but also provide an alternative way to integrate the different charging protocols into a single QB.
Improving the spatial resolution of artificial vision using midget retinal ganglion cell populations modeled at the human fovea
Authors: Italiano Michael L , Guo Tianruo , Lovell Nigel H , Tsai David
Published: May 2022

Objective. Retinal prostheses seek to create artificial vision by stimulating surviving retinal neurons of patients with profound vision impairment. Notwithstanding tremendous research efforts, the performance of all implants tested to date has remained rudimentary, incapable of overcoming the threshold for legal blindness. To maximize the perceptual efficacy of retinal prostheses, a device must be capable of controlling retinal neurons with greater spatiotemporal precision. Most studies of retinal stimulation were derived from either non-primate species or the peripheral primate retina. We investigated if artificial stimulation could leverage the high spatial resolution afforded by the neural substrates at the primate fovea and surrounding regions to achieve improved percept qualities. Approach. We began by developing a new computational model capable of generating anatomically accurate retinal ganglion cell (RGC) populations within the human central retina. Next, multiple RGC populations across the central retina were stimulated in-silico to compare clinical and recently proposed neurostimulation configurations based on their ability to improve perceptual efficacy and reduce activation thresholds. Main results. Our model uniquely upholds eccentricity-dependent characteristics such as RGC density and dendritic field diameter, whilst incorporating anatomically accurate features such as axon projection and three-dimensional (3D) RGC layering, features often forgone in favor of reduced computational complexity. Following epiretinal stimulation, the RGCs in our model produced response patterns in shapes akin to the complex and non-trivial percepts reported in clinical trials. Our results also demonstrated that even within the neuron-dense central retina, epiretinal stimulation using a multi-return hexapolar electrode arrangement could reliably achieve spatially focused RGC activation and could achieve single-cell excitation in 56% of all tested locations. Significance. This study establishes an anatomically accurate 3D model of RGC populations within the human central retina and demonstrates the potential for an epiretinal hexapolar configuration to achieve consistent, spatially confined retinal responses, even within the unique and neuron-dense foveal region. Our results and model promote the prospect and optimization of higher spatial resolution in future epiretinal implants.
Assessment of advanced fluid neutral models for the neutral atoms in the plasma edge and application in ITER geometry
Authors: Van Uytven Wim , Dekeyser Wouter , Blommaert Maarten , Carli Stefano , Baelmans Martine
Published: May 2022

The neutral atoms in the plasma edge of nuclear fusion devices are typically modeled using either a fluid or kinetic approach. The kinetic approach is most accurate, but it has two main disadvantages. First, the usual solution of the high-dimensional kinetic equation using Monte Carlo techniques introduces statistical noise, which hampers the convergence of the coupled plasma-neutral model. Second, the computational time strongly increases for highly collisional regimes. For these reasons, deterministic fluid neutral models remain an attractive alternative, in particular for the highly collisional conditions where their accuracy is expected to be high. In recent years, efforts have been undertaken to improve the agreement between the fluid and kinetic approach by introducing consistent transport coefficients and consistent boundary conditions in the fluid models. In this work, these so-called advanced fluid neutral models are further enhanced by introducing different strategies to cope with the high heterogeneity of the ion-neutral collisionality encountered in realistic plasma-edge geometries, namely isotropic neutral flux limiters and an automated selection criterion for the optimal neutral boundary conditions. The validity of the resulting fluid neutral models is thoroughly assessed for various representative simulation cases with different geometries, divertor collisionalities, and wall materials, including, for the first time, simulations in a realistic ITER plasma edge geometry. Strong quantitative agreement between the fluid and kinetic models is achieved for cases with highest divertor collisionality.
Granular Matrigel: restructuring a trusted extracellular matrix material for improved permeability
Authors: Mahdieh Zahra , Cherne Michelle D , Fredrikson Jacob P , Sidar Barkan , Sanchez Humberto S , Chang Connie B , Bimczok Diane , Wilking James N
Published: May 2022

Matrigel is a polymeric extracellular matrix material produced by mouse cancer cells. Over the past four decades, Matrigel has been shown to support a wide variety of two- and three-dimensional cell and tissue culture applications including organoids. Despite widespread use, transport of molecules, cells, and colloidal particles through Matrigel can be limited. These limitations restrict cell growth, viability, and function and limit Matrigel applications. A strategy to improve transport through a hydrogel without modifying the chemistry or composition of the gel is to physically restructure the material into microscopic microgels and then pack them together to form a porous material. These ‘granular’ hydrogels have been created using a variety of synthetic hydrogels, but granular hydrogels composed of Matrigel have not yet been reported. Here we present a drop-based microfluidics approach for structuring Matrigel into a three-dimensional, mesoporous material composed of packed Matrigel microgels, which we call granular Matrigel. We show that restructuring Matrigel in this manner enhances the transport of colloidal particles and human dendritic cells (DCs) through the gel while providing sufficient mechanical support for culture of human gastric organoids (HGOs) and co-culture of human DCs with HGOs.
Synthesis of smart carriers based on tryptophan-functionalized magnetic nanoparticles and its application in 5-fluorouracil delivery
Authors: Tokmedash Mohammad Asadi , Seyyedi Zadeh Elham , Balouchi Elham Nezami , Salehi Zeinab , Ardestani Mehdi Shafiee
Published: May 2022

Multifunctional nanocarriers, specifically for tumor targeting and traceable features, have been increasingly considered in cancer therapies. Herein, a novel targeting agent (TA), tryptophan (TRP), was proposed for the synthesis of functionalized (3-aminopropyl) triethoxysilane-iron oxide nanoparticles using two methods, creating a smart drug delivery system (DDS). In one method, two-step, glutaraldehyde (GA) as a linker, bonded TRP and amino-functionalized magnetite, and in the second method, one step, TRP binding was carried out by (3-dimethyl aminopropyl)-N’-ethyl carbodiimide hydrochloride (EDC)/N-hydroxysuccinimide ester. The synthesis yield of the second method was 7% higher than the first method. After synthesizing DDS, 5-fluorouracil (5-FU) was loaded on nanocarriers and was observed TRP functionalized nanoparticles by GA have better loading efficiency, which was 50% greater than the product from the one-step method. A pH-sensitive release profile was also studied for 5-FU/DDS with the release of almost 75% and 50% at pH 5.5 and 7.4, respectively. To analyze the biological aspects of nanocarriers, human breast cancer, MCF-7, and embryonic kidney, HEK293, cell lines were used for cellular uptake and 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assays. In vitro studies confirmed that TRP can act as a TA as its cellular uptake through cancerous cells was 40% greater than normal cells, and the MTT assay confirmed that using DDS can increase and decrease the cell viability of normal cells and cancerous cells, respectively, compared to free drug. Therefore, it was concluded that advanced nano-assembly is a great candidate for breast cancer cell-targeted delivery.
Community-based participatory research for low-cost air pollution monitoring in the wake of unconventional oil and gas development in the Ohio River Valley: Empowering impacted residents through community science
Authors: Raheja Garima , Harper Leatra , Hoffman Ana , Gorby Yuri , Freese Lyssa , O’Leary Brendan , Deron Nathan , Smith Shannon , Auch Ted , Goodwin Melissa , Westervelt Daniel M
Published: May 2022

Belmont County, Ohio is heavily dominated by unconventional oil and gas development that results in high levels of ambient air pollution. Residents here chose to work with a national volunteer network to develop a method of participatory science to answer questions about the association between impact on the health of their community and pollution exposure from the many industrial point sources in the county and surrounding area and river valley. After first directing their questions to the government agencies responsible for permitting and protecting public health, residents noted the lack of detailed data and understanding of the impact of these industries. These residents and environmental advocates are using the resulting science to open a dialogue with the EPA in hopes to ultimately collaboratively develop air quality standards that better protect public health. Results from comparing measurements from a citizen-led participatory low-cost, high-density air pollution sensor network of 35 particulate matter and 25 volatile organic compound sensors against regulatory monitors show low correlations (consistently R2 < 0.55). This network analysis combined with complementary models of emission plumes are revealing the inadequacy of the sparse regulatory air pollution monitoring network in the area, and opening many avenues for public health officials to further verify people’s experiences and act in the interest of residents’ health with enforcement and informed permitting practices. Further, the collaborative best practices developed by this study serve as a launchpad for other community science efforts looking to monitor local air quality in response to industrial growth.
Multidecadal variability of ENSO in a recharge oscillator framework
Authors: Crespo Lander R , Belén Rodríguez-Fonseca Mª , Polo Irene , Keenlyside Noel , Dommenget Dietmar
Published: May 2022

We use a conceptual recharge oscillator model to identify changes in El Niño and the Southern Oscillation (ENSO) statistics and dynamics during the observational record. The variability of ENSO has increased during the 20th century. The cross-correlation between sea surface temperature (SST) and warm water volume (WWV) has also changed during the observational record. From the 1970s onwards, the SST drives WWV anomalies with a lead-time of ten months and the WWV feedbacks onto the SST with a lead-time of eight months. This is reminiscent of a recharge-discharge mechanism of the upper ocean heat content. The full recharge-discharge mechanism is only observed from the 1970s onwards. This could be the result of the degradation of the quality of observations in the early part of the 20th century. However, it may also be a consequence of decadal changes in the coupling between WWV and SST. Additional analysis fitting the recharge oscillator model to the coupled state-of-the-art climate models indicates that ENSO properties show little decadal changes in the climate models. The disagreement in changes in ENSO properties between the reanalysis and the climate models can be due to errors in the available observational data or due to the models missing the low frequency variability and decadal wind trends. Longer and more reliable observational records would be required to validate our results.
Improving the relationships between Indigenous rights holders and researchers in the Arctic: an invitation for change in funding and collaboration
Authors: Doering Nina Nikola , Dudeck Stephan , Elverum Shelly , Fisher Charleen , Henriksen Jan Erik , Herrmann Thora Martina , Kramvig Britt , Laptander Roza , Milton Justin , Omma Elle Merete , Saxinger Gertrude , Scheepstra Annette J M , Wilson Katherine
Published: May 2022

Truly transdisciplinary approaches are needed to tackle the complex problems that the Arctic is facing at the moment. Collaboration between Indigenous rights holders and researchers through co-creative research approaches can result in high-quality research outcomes, but crucially also address colonial legacies and power imbalances, enhance mutual trust, and respect the rights of Indigenous Peoples. However, to be successful, collaborative research projects have specific requirements regarding research designs, timeframes, and dissemination of results, which often do not fit into the frameworks of academic calendars and funding guidelines. Funding agencies in particular play an important role in enabling (or disabling) meaningful collaboration between Indigenous rights holders and researchers. There is an urgent need to re-think existing funding-structures. This article will propose a new paradigm for the financing of Arctic research, which centres around the inclusion of Indigenous partners, researchers, and institutions from the initial planning stages of funding programmes to the final stages of research projects. These findings and recommendations have been contextualized based on critical reflections of the co-authors, a group of Indigenous and non-Indigenous partners, who have practiced their own collaborative work process, the challenges encountered, and lessons learned.
Large-scale citizen science programs can support ecological and climate change assessments
Authors: Crimmins Theresa M , Crimmins Michael A
Published: May 2022

Large-scale citizen science programs have the potential to support national climate and ecosystem assessments by providing data useful in estimating both status and trends in key phenomena. In this study, we demonstrate how opportunistic, unbalanced observations of biological phenomena contributed through a national-scale citizen science program can be used to (a) identify and evaluate candidate biotic climate change indicators and (b) generate yearly estimates of status of selected indicators. Using observations of plant phenology contributed toNature’s Notebook, the USA National Phenology Network’s citizen science program, we demonstrate a procedure for identifying biotic indicators as well as several approaches leveraging these opportunistically-sampled data points to generate yearly status measures. Because the period of record for this dataset is relatively short and inconsistently sampled (13 yr), we focus on estimates of status, though over time, these measurements could be leveraged to also estimate trends. We first applied various spatial, seasonal, and biological criteria to narrow down the list of candidate indicators. We then constructed latitude-elevation models for individual species-phenophase events using all observations. This allowed us to visualize differences between predicted and reported phenophase onset dates in a year as anomalies, with the expectation that these anomalies—representing earlier or later activity in the species of interest—reflect plant response to local springtime temperatures. Plotting yearly anomalies revealed regions with geographic coherence as well as outliers. We also show how yearly anomaly values can be reduced to a single measure to characterize the early or late nature of phenological activity in a particular year. Finally, we demonstrate how the latitude-elevation models can be leveraged to characterize the pace at which phenological transitions occur along latitude gradients on a year-by-year basis.
Decomposing the effect of anomalous diffusion enables direct calculation of the Hurst exponent and model classification for single random paths
Authors: Meyer Philipp G , Aghion Erez , Kantz Holger
Published: May 2022

Recently, a large number of research teams from around the world collaborated in the so-called ‘anomalous diffusion challenge’. Its aim: to develop and compare new techniques for inferring stochastic models from given unknown time series, and estimate the anomalous diffusion exponent in data. We use various numerical methods to directly obtain this exponent using the path increments, and develop a questionnaire for model selection based on feature analysis of a set of known stochastic processes given as candidates. Here, we present the theoretical background of the automated algorithm which we put for these tasks in the diffusion challenge, as a counter to other pure data-driven approaches.
Island and lake size distributions in gradient percolation
Authors: Manna S S
Published: May 2022

The well known problem of gradient percolation has been revisited to study the probability distribution of island sizes. It is observed that like the ordinary percolation, this distribution is also described by a power law decaying function but the associated critical exponents are found to be different. Because of the underlying gradient for the occupation probability, the average value of the island sizes also has a gradient. The variation of the average island size with the probability of occupation along the gradient has been studied together with its scaling analysis. Further, we have introduced and studied the gradient bond percolation and on studying the island size distribution statistics, we have obtained very similar results. We have also studied the characteristics of the diffusion profile of the particle system on a lattice which is initially half filled and half empty. Here also we observe the same value for the island size probability distribution exponent. Finally, the same study has been repeated for the nonlinear gradient percolation and the value of the island size distribution exponent is found to be a function of the strength of the nonlinear parameter.
Processing and use of waste from the mining industry
Authors: Golik V I , Polovneva S I , Turluyev R R
Published: May 2022

An increase in the extraction of resources is accompanied by their losses and dilution of ores due to the technogenic impact on ore-bearing massifs. The possibility of preserving the earth’s surface is provided by technologies with filling technological voids with hardening mixtures based on leach tailings, the insufficient activity of which is increased by processing in disintegrators under the influence of high energy. Experimental proof of the possibility of controlling the state of the hardening mixture was obtained in the course of many years of use of the disintegrator as part of the filling complex. The possibility of replacing cement with activated tailings has been proven not only as inert fillers but also as binders, which makes it possible to replace commercial cement with cheaper production of commercial products. Utilization of metals from enrichment tailings of various types of minerals allows the use of secondary tailings without restrictions on sanitary requirements. The combined effect of mechanical and chemical energies allows waste-free disposal of enrichment tailings and creates, in essence, a new base of metal raw materials to meet the needs of industry.
Evaluation of the variability of the oil viscosity of the Permian-Carboniferous reservoir Usinskoye field
Authors: Kultysheva S N , Raspopov A V , Khizhnyak G P
Published: May 2022

The article describes the results of assessing the variability of the viscosity of reservoir oil from the Permian-Carboniferous reservoir of the Usinsk field, obtained on the basis of sampling, research and analysis of downhole samples. Emphasis is placed on the study of oil properties (viscosity, gas content, molar mass, resin content, etc.) in the edge of the reservoir; a number of regularities in the change in viscosity over the area and section of the reservoir have been identified, which can later be used to optimize technologies for the development of super-viscous oil.
A study of the effect of the limiting shear gradient on the pressure recovery curve during hydraulic fracturing
Authors: Yusupova L F , Khusnutdinova R R , Gilyazetdinov R A , Almukhametova E M
Published: May 2022

The article analyzes the effect of the limiting shear gradient of viscoplastic oil on the results of interpretation of well testing by the pressure recovery curve (PRC) method following the methods of stimulation by hydraulic fracturing. The lack of mobile water in the collector was analyzed. An analysis of the effect of the limiting shear gradient on the pressure build-up curve and interpretation results was conducted. According to the results of interpretation by the pressure recovery curve method in the presence of a limiting shear gradient in oil, curves were constructed for various dependences and deviations were revealed.
Analysis of the state of exploitation of flooded Mesozoic reservoirs of the Grozny oil-bearing region exposed to anthropogenic impact
Authors: Khaladov A Sh , Bulchaev N D , Duskaev M Z , Bakaev M-A E , Taramov Yu Kh , Khasiev D Kh , Gazabieva Z Kh , Yamaletdinova A A
Published: May 2022

One of the main features of the exploitation of Mesozoic reservoirs in the Grozny oil-bearing region is an extremely short life of flooded production wells, which lasts not more than 10% of productive life from water appearance in the well production to its complete flooding.
Methods for forecast of oil-bearing capacity by the example of the JS2/1 layer within the Surgut arch
Authors: Turabaeva A V , Belkina V A
Published: May 2022

In order to increase the efficiency of geological exploration (GE), adequate geological models (AGM) must be created, enabling the identification of the most prospective oil-bearing areas. It should be pointed out that an extensive base of methods for building AGM exists nowadays. At the same time, there are practically no publications on substantiation of formalised criteria for ranking zones for GE with various geological risks. This paper proposes a model that provides ranking of the area according to the quality of reservoir rocks, based on the model’s strict decision rule. Based on the joint analysis of the quality maps of reservoir rocks and paleorelief, an oil potential map has been built. Efficiency of the method is shown by the example of the JS2/1 layer of continental genesis, characterised by the complex geological structure.
Karachay-Cherkessia – international landscape and geoecological landfill
Authors: Kipkeeva P A , Potapenko Ya Yu , Shubaeva N V. , Abaykhanova A A , Borlakova F M
Published: May 2022

Landscape and geoecological study served a response to global climate change and the threat of a global environmental crisis. The scientists of the Teberdinsky State Biosphere Reserve, Stavropol State University and the Department of Natural Geography of Karachay-Cherkess State University made the greatest contribution to the development of this sphere. Modern study on geology, geography, biology, toponymy, geomorphology, geoecology was conducted, an improved methodology for assessing the degree of anthropogenic impact on the natural environment was proposed, GIS technologies were mastered and introduced into the education and research. In 2019, the 1st International Conference was held in Karachaevsk, the main principle of which was the concept of balanced development of mountain territories.
The effect of polymer-cement mortars with additives of aluminosilicate microspheres on the reservoir properties of exploration and production wells
Authors: Kadyrov R R , Mukhametshin V V , Kuleshova L S , Kobishcha D I , Safiullina A R
Published: May 2022

The article shows that the use of lightweight grouting solution with hollow aluminosilicate microspheres can reduce the time and the cost of materials spent on securing exploration wells, ensure the rise of solution to the design height. Improved strength and fracturing of the stone ensures resistance to fracture during perforation, and a sufficiently strong bond can ensure tightness of the annulus in exploration and production wells.
Oil Potential Prospects of Domanik sediments in the North-East of the Volga-Urals
Authors: Krivoshchekov S N
Published: May 2022

Due to the depletion of available mineral and raw material resources of conventional sediments there is a need to search for new promising areas of oil and gas exploration in Perm Krai. This article addresses Domanik sediments as a new source of hydrocarbons. Stratigraphically, these sediments belong to the Sargayev, Domanik and Mendym horizons and lithologically they are mainly represented by tight carbonate sediments and shales. These sediments are the main oil-source strata in the Volga-Ural province. The paper analyses the geological structure and distribution of these sediments in the study area. Thereupon, exploration recommendations have been formulated for the next few years. These mainly include subject-matter research, core sampling in the Domanik Formation sediments, special studies of reservoir properties, reactivation and study of discovered oil deposits in the Domanik strata. The main activities should be concentrated in the south and south-west of Perm Krai: in the area of the Bashkir Arch, in the south of the Upper-Kama Depression. The Solikamsk Depression is also of interest in this respect.
Technogenic impact on the environment during leaching
Authors: Razorenov Yu I , Klyuev R V , Guzueva E R
Published: May 2022

The results of the analysis of the theory and practice of leaching metals from substandard raw materials are presented. A brief historical reference is given on the leaching of metals from experimental leaching in the middle of the last century to industrial development in modern times. The direction of combining traditional and innovative technologies within a single technological process is formulated. The mechanism of underground block leaching of ores is described. A complex method of multi-factorial assessment of the existing natural and man-made factors of development is proposed. The parameters of the proposed technology and some aspects of its application are substantiated. Using the method of engineering forecasting, the prospects for leaching metals from substandard raw materials are assessed. The main results of the development of underground leaching of metals from sub-standard raw materials and the prospects for improving the method with the rational combination of underground leaching technologies with traditional mining technologies are formulated. It is concluded that the leaching of metals from substandard raw materials has prospects for development.
Use of acid fracturing to increase the production potential of subsoil users
Authors: Siraeva G M , Fattakhov I G , Kuleshova L S , Stepanova R R
Published: May 2022

The paper reflects the main problems of the search and development of Domanic deposits, including the following: complexity of the area search for promising sites; difficulty in extracting reservoir beds from well geophysical survey (GIS) data; low permeability of formations; low profitability of oil production; difficulty in reserve estimate and and registration. Oil and gas companies face problems such as the lack of reliable information on Domanic deposits from specific GIS studies, core samples, a significant risk of obtaining unprofitable flow rates, and a low degree of adaptation of existing oil production technologies to the products of Domanic deposits. The formation of reserves with mobile hydrocarbons is influenced by such parameters as: degree of maturity of source rocks; composition of substances; amount of minerals that determine the maturation of the organic substance and formation of the reservoir; presence of intervals with increased fragility, presence of impermeable layers that ensure the safety of deposits, etc. It was shown that the Domanic deposits should be developed using horizontal wells and multi-stage acid hydraulic fracturing treatment (HFT).
Forecasting the hydraulic fracturing efficiency when selecting wells for an event
Authors: Valeev A I , Mukhametshin V Sh , Anisimov V V
Published: May 2022

To this date, most of the oil and gas reserves are hard-to-recover, that is, they are located in deposits confined to low-permeability reservoirs. Hydraulic fracturing treatment (HFT) is one of the methods of production stimulation that allows making the oil recovery profitable from such reservoirs. The given article discusses regression analysis to predict HFT efficiency and select candidate wells.
Geological and statistical simulation for assessment of zonal oil and gas potential formation processes in the Visimskaya monocline
Authors: Galkin V I , Koshkin K A , Melkishev O A , Kozlova I A
Published: May 2022

The paper considers probabilistic approach application to assess zonal oil and gas potential of the Visimskaya monocline area. The earlier studies have shown that the processes of generation, migration and accumulation of hydrocarbons (HC) shall be most effectually assessed from a probabilistic standpoint. Generation processes are best described by a complex probabilistic criterion – PcompG
, migration and accumulation processes – by PcompMAC
[1]. These criteria were used to develop a multivariate statistical model – Pcompzon
, acting as an estimate of the system emergence regarding the zonal oil and gas potential. The values were ranked from maximum to minimum to assess the effect of PcompG
and PcompMAC
indicators on Pcompzon
at different ranges of its values. We successively built and analysed 379 models. The analysis of these models has shown that at Pcompzon>0.5 there is a congruent effect of PcompG
and PcompMAC
on this indicator, the effect being different at Pcompzon<0.5. A pattern of its variation over the area was built based on Pcompzon
values, which allowed differentiating the area of the Visimskaya monocline into a high-potential western part and a lower-potential eastern part.
Geological and Technological Parameters and Development of Deposits in Carbonate Reservoirs to Solve Exploration Tasks
Authors: Mukhametshin V Sh
Published: May 2022

More than 30 geological and technological parameters to affect the predicted production of reserves in carbonate reservoirs were studied to solve exploration tasks. A physical interpretation of the findings is given. The paper concludes that there is a need for complex geological and statistical modeling. The analysis does not give the parameters that most largely determine oil recovery due to their cross-correlation dependence. The final answer can be provided by a comprehensive oil recovery model involving all parameters and an analysis of cause-and-effect relationships.
Laboratory studies on the use of surfactant compositions to solve resource extraction problems
Authors: Ngia Ty Than , Veliev M M , Mukhametshin V Sh , Karimov S S , Veliev E M , Andreev A V
Published: May 2022

Based on studies on the interaction and heat resistance of some heat-resistant polymer additives at 128 °C, a sulfonated polyacrylamide polymer AN-125 is proposed as an additive for improving the viscosity of a surfactant composition. The results of experimental studies of a new surfactant composite prepared based on a mixture of ethoxylated and propoxylated sulfate, α-olefin sulfonate and alkylphenol ethoxylate with a concentration of 500 ppm and additives to improve the viscosity in the reservoir model from the deposit basement samples showed that the surface tension at the oil-solution boundary before the exposure to temperature is 0.19 mN/m, and after exposure to temperature 91 °C – 0.21 mN/m. The experimental studies of water and surfactant compositions injection on 5 prefabricated models composed of core samples of basement rocks covering a wide range of reservoir properties showed that the injection of the oil rim with compositions based on the mixture of ethoxylated and propoxylated sulfate, α-olefin sulfonate and alkylphenol ethoxylate with a concentration of 800 ppm and an additive of polymerasulfonated polyacylate increases the oil displacement ratio.
Possibilities of using fiber-optic sensors in the study of oil and gas wells
Authors: Shiryaev E O , Rybka V F , Kolychev I Yu
Published: May 2022

With an increase in the accuracy of fiber-optic sensors, the possibility of their use in various fields is being formed. In this article, the authors present their own experience in the implementation of fiber-optic technologies in geophysical surveys of wells, indicate current problems and prospects for the development of this direction in the region of activity. Since 2014, LLC “PITC Geofizika” has been actively developing the direction of fiber-optic temperature measurement systems. To date, these are measurements in more than 40 wells (15 wells are being measured at present time). As a result, we can say that today there is already a certain niche in the basket of the geophysical sector, confidently occupied with fiber-optic sensors technologies, but the prospects for the development of this technology are significant and are fully revealed only in the process of work. However, it is worth approaching the implementation of this method only with a complete understanding of the processes occurring in the well.
Assessment of applicability of preformed particle gels for Perm region oil fields
Authors: Rozhkova Yu A , Gurbanov V Sh , Efendiyev G M , Galkin S V
Published: May 2022

The application of preformed particle gels (PPG) in Russian oil fields is very limited. In this research the authors tried to find tools for primary screening of oil wells candidates for PPG application. For a fractured reservoir, the Warren-Rutt method was considered for estimating fracture sizes in injected oil wells. Taking into account the mechanical properties of the developed PPG, a powder fraction is recommended for starting treatment of oil wells. An express method for assessing the pressure index (PI) was considered for the primary selection of well candidates. PI provides information on reservoir heterogeneity. Using this method, the most promising candidates for the implementation of PPG technology were selected.
Diagnostics of traction motor of 1DT.003.11 type of electric train EP3D by modeling fuzzy linguistic parameters in matlab and fuzzy tech environment
Authors: Menshikov I A , Shorina A.V. , Kargin V A , Volgin A V , Moiseev A P , Volgina E V
Published: May 2022

The article presents the results of research in the field of diagnostics of a traction electric motor of the 1DT.003.11 type of the alternating current electric train of the EP3D series by simulating emergency modes of functioning of the fuzzy logic of a modular dynamical neural network. It is proposed to solve the problems of assessing the reliability of traction electric motors in railway transport with an increased service life using simulation modeling of the ANFIS modular neural network in the MATLAB package. The result of modeling the statistical diagnostic parameters of the traction motor is an assessment of the change in the linguistic coefficients of the residual life of the traction motor of the EP3D electric train and recommendations for the maintenance of traction electric motors, depending on their technical condition at the current time of operation.
Cofreeness in real bordism theory and the segal conjecture
Authors: Carrick Christian
Published: May 2022

We prove that the genuineC2nC_{2^n}-spectrumNC2C2nMURN_{C_{2}}^{C_{2^n}}MU_{\mathbb {R}}is cofree, for allnn. Our proof is a formal argument using chromatic hypercubes and the Slice Theorem of Hill, Hopkins, and Ravenel. We show that this gives a new proof of the Segal Conjecture forC2C_2, independent of Lin’s theorem.
ASHP National Survey of Pharmacy Practice in Hospital Settings: Clinical services and workforce—2021
Authors: Schneider Philip J , Pedersen Craig A , Ganio Michael C , Scheckelhoff Douglas J
Published: May 2022

Purpose

Results of the 2021 ASHP National Survey of Pharmacy Practice in Hospital Settings are presented.

Methods

Pharmacy directors at 1,498 general and children’s medical/surgical hospitals in the United States were surveyed using a mixed-mode method of contact by email and mail. Survey completion was online. IQVIA supplied data on hospital characteristics; the survey sample was drawn from IQVIA’s hospital database.

Results

The response rate was 21.9%. Pharmacists are routinely assigned to a majority of patients at least 8 hours per day, 5 days per week in 70.4% of hospitals. This is an increase from 60.8% in 2018 and has steadily increased over the past decade. Pharmacists independently prescribe medications pursuant to a diagnosis in 30.9% of hospitals, an increase from 21.1% in 2020. Pharmacists have prescribing authority in 67% of health-system ambulatory clinics and can recommend or schedule pharmacogenomics testing for drug and dosage selection in 11.4% of hospitals, an increase from 5.4% in 2019. Pharmacists are using electronic methods in 82.5% of hospitals to collect information for monitoring medication therapy. Shortages of entry-level pharmacy technicians are acute, with 73.4% of survey respondents reporting a shortage. Technician shortages have affected pharmacy operations and have prompted new recruitment and retention strategies.

Conclusion

Despite workforce challenges, clinical pharmacy services continue to expand to cover increasing numbers of patients with medication management services in both the inpatient and outpatient settings. The use of data analytics and pharmacy technicians has contributed to this evolution. Addressing the workforce challenges will be critical to sustain this progress.
The cost of attentional reorienting on conscious visual perception: an MEG study
Authors: Spagna Alfredo , Bayle Dimitri J , Romeo Zaira , Seidel-Malkinson Tal , Liu Jianghao , Yahia-Cherif Lydia , Chica Ana B , Bartolomeo Paolo
Published: May 2022

How do attentional networks influence conscious perception? To answer this question, we used magnetoencephalography in human participants and assessed the effects of spatially nonpredictive or predictive supra-threshold peripheral cues on the conscious perception of near-threshold Gabors. Three main results emerged. (i) As compared with invalid cues, both nonpredictive and predictive valid cues increased conscious detection. Yet, only predictive cues shifted the response criterion toward a more liberal decision (i.e. willingness to report the presence of a target under conditions of greater perceptual uncertainty) and affected target contrast leading to 50% detections. (ii) Conscious perception following valid predictive cues was associated to enhanced activity in frontoparietal networks. These responses were lateralized to the left hemisphere during attentional orienting and to the right hemisphere during target processing. The involvement of frontoparietal networks occurred earlier in valid than in invalid trials, a possible neural marker of the cost of re-orienting attention. (iii) When detected targets were preceded by invalid predictive cues, and thus reorienting to the target was required, neural responses occurred in left hemisphere temporo-occipital regions during attentional orienting, and in right hemisphere anterior insular and temporo-occipital regions during target processing. These results confirm and specify the role of frontoparietal networks in modulating conscious processing and detail how invalid orienting of spatial attention disrupts conscious processing.
Duration of Replication-Competent Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Shedding Among Patients With Severe or Critical Coronavirus Disease 2019 (COVID-19)
Authors: Kim Do Young , Lin Michael Y , Jennings Cheryl , Li Haiying , Jung Jae Hyung , Moore Nicholas M , Ghinai Isaac , Black Stephanie R , Zaccaro Daniel J , Brofman John , Hayden Mary K ,   for the CDC Prevention Epicenter Program
Published: May 2022

Background

Patterns of shedding replication-competent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in severe or critical COVID-19 are not well characterized. We investigated the duration of replication-competent SARS-CoV-2 shedding in upper and lower airway specimens from patients with severe or critical coronavirus disease 2019 (COVID-19).

Methods

We enrolled patients with active or recent severe or critical COVID-19 who were admitted to a tertiary care hospital intensive care unit (ICU) or long-term acute care hospital (LTACH) because of COVID-19. Respiratory specimens were collected at predefined intervals and tested for SARS-CoV-2 using viral culture and reverse transcription–quantitative polymerase chain reaction (RT-qPCR). Clinical and epidemiologic metadata were reviewed.

Results

We collected 529 respiratory specimens from 78 patients. Replication-competent virus was detected in 4 of 11 (36.3%) immunocompromised patients up to 45 days after symptom onset and in 1 of 67 (1.5%) immunocompetent patients 10 days after symptom onset (P = .001). All culture-positive patients were in the ICU cohort and had persistent or recurrent symptoms of COVID-19. Median time from symptom onset to first specimen collection was 15 days (range, 6–45) for ICU patients and 58.5 days (range, 34–139) for LTACH patients. SARS-CoV-2 RNA was detected in 40 of 50 (80%) ICU patients and 7 of 28 (25%) LTACH patients.

Conclusions

Immunocompromise and persistent or recurrent symptoms were associated with shedding of replication-competent SARS-CoV-2, supporting the need for improving respiratory symptoms in addition to time as criteria for discontinuation of transmission-based precautions. Our results suggest that the period of potential infectiousness among immunocompetent patients with severe or critical COVID-19 may be similar to that reported for patients with milder disease.
Design and multiperspectivity-based performance investigations of H-Darrieus vertical axis wind turbine through computational fluid dynamics adopted with moving reference frame approaches
Authors: Balamurugan Rohini Janaki , AL-bonsrulah Hussein A Z , Raja Vijayanandh , Kumar Lokeshkumar , Kannan Sri Diviyalakshmi , Madasamy Senthil Kumar , Rasheed Raffik , Rajendran Parvathy , Al-Bahrani Mohammed
Published: May 2022

The power output of a straight-bladed H-rotor Darrieus vertical axis wind turbine (HDVAWT) is explored in this article. The comparisons are performed between the NACA0018 airfoil and a series of Kline Fogelman modified NACA0018 airfoils. The computational fluid dynamics findings are first cross-checked with the experimental data, and the computational processes are validated as a consequence. Then, in CATIA, 12 airfoils were constructed by modifying the step thickness, step placement and trailing edge form to get an efficient model for the wind turbine. The approved computational processes are applied to all 13 models, and the results are obtained. In comparison to the NACA 0018 airfoil, the KFm3 airfoil with 12% step thickness and a rectangular trailing edge demonstrated a 47% efficiency under 6.65 m/s wind velocity and a rotational velocity of 120 RPM. The KFm3 airfoil also performed better when tested at 80 and 162 RPMs. Thus, the final HDVAWT has been presented for real-time applications, which is the primary goal of this work; also, the proposed HDVAWT outperforms all existing vertical axis wind turbines.
Restricted Tangent Bundles for General Free Rational Curves
Authors: Lehmann Brian , Riedl Eric
Published: May 2022

Suppose that $X$ is a smooth projective variety and that $C$ is a general member of a family of free rational curves on $X$. We prove several statements showing that the Harder–Narasimhan filtration of $T_{X}|_{C}$ is approximately the same as the restriction of the Harder–Narasimhan filtration of $T_{X}$ with respect to the class of $C$. When $X$ is a Fano variety, we prove that the set of all restricted tangent bundles for general free rational curves is controlled by a finite set of data. We then apply our work to analyze Peyre’s “freeness” formulation of Manin’s Conjecture in the setting of rational curves.
Molecular Evolution and Epidemiology of Parechovirus-A3 in Japan, 1997–2019
Authors: Aizawa Yuta , Kasamatsu Takuhiro , Nagasawa Koo , Watanabe Kanako , Saitoh Akihiko
Published: May 2022

Parechovirus-A3 (PeV-A3), first reported in 2004 in Japan, is an emerging pathogen that causes sepsis and meningoencephalitis in neonates and young infants. Although PeV-A3 has been identified worldwide, its epidemiological characteristics differ by region. To investigate the molecular evolution and epidemiology of PeV-A3, we performed genetic analyses of 131 PeV-A3 strains from the years 1997–2019 in Niigata, Japan. During 2016–2019, annual numbers remained steady, in contrast to the PeV-A3 epidemic interval of every 2–3 years that was observed in Japan from 2006. Bayesian evolutionary analysis of the complete viral protein 1 region revealed alternate dominant clusters during years of PeV-A3 epidemics. The branch including the oldest and first isolated PeV-A3 strains in Japan has been disrupted since 2001. The year of PeV-A3 emergence was estimated to be 1991. Continuous surveillance with genetic analyses of different regions will improve understanding of PeV-A3 epidemiology worldwide.