bluuebunny/crossref_metadata_2025 huggingface dataset:
Location of deposits of non-metallic ores in Russia and the technogenic impact of mining on the environment
Authors: Kozhiev Kh Kh , Gabaraev O Z , Khaliev M S-U
Published: May 2022

The article substantiates the need to strengthen the mineral resource base for the production of non-ferrous metals through the involvement in the operation of substandard raw materials, primarily those stored in tailings dumps for the enrichment of metal ores. The results of the analysis of reserves of ore deposits are presented in comparison with the situation in the world. Quantitative data on the state of the mineral resource base of non-ferrous metal ores in Russia and the provision of industry with metal raw materials are given. The role of mineral resources in protecting the geopolitical interests of Russia is shown. It is noted that Russia lags behind technologically developed countries in a number of indicators of production and consumption of mineral resources. It is concluded that the development of technogenic deposits using innovative technologies is a real step towards strengthening the mineral resource base of Russia, therefore, research on the direction of mining mentioned in the article is relevant.
Influence of formation drilling conditions on the choice of well stimulation method
Authors: Gabzalilova A Kh , Garifullina Z A
Published: May 2022

The paper considers the influence of crank radius change on pumping unit kinematics during the dynamic fluid level control between tubing and casing in order to reduce the string fault rate. To improve the quality of prediction of these factors, the calculation of the movement of the polished rod over time is carried out using the Fourier variable separation method: the product of the balance bar head of a pumping unit defined as the movement of the slider of the pumping mechanism (in a straight line – like the chords of a circle), and the difference of such a chord with the length of the circle section equivalent to the movement of the articulated joint of the balance bar with the connecting rod. As a result, the accuracy of calculations is improved and the solution of the problem is simplified.
Environmental and natural leaching processes in underground ore mining
Authors: Galachieva S V , Stas G V , Izotova I I
Published: May 2022

The minimization of the negative impact of the products of natural leaching of metal ores on the ecosystems of the environment is justified. It is shown that the reason for the formation of ore leaching solutions is the use of development technologies without filling voids. The results of observations are systematized and the concept of environmental management by combining the potentials of enterprises in the region is substantiated. The efficiency of using dolomite waste to reduce the leaching front by filling technological voids with dolomite-based mixtures is shown. The results of the study of the intensity and danger of natural leaching, taking into account the zoning of mineralization within the orefield, are presented. Measures to reduce the level of natural leaching are recommended. A leaching model is proposed that describes physicochemical processes as stages of reactions occurring in the ore mass. The algorithm of substantiation of environmental technologies is given. The ecological and economic criterion of the effectiveness of the implementation of environmental measures is proposed. The processes of natural leaching of metals are adequate, which makes it possible to control their development. Natural leaching is a consequence of the insufficient level of applied development technologies and can be minimized.
Ecology and utilization of ore dressing tailings
Authors: Gabaraev O Z , Konovalova T G , Turluev R R
Published: May 2022

Based on the study of ways to increase the efficiency of metal production through the use of technologies for leaching substandard ores in terms of metal content, a data bank was formed and an algorithm for controlling the processes of leaching substandard non-ferrous ores in terms of metal content was proposed. The concept of the development of technogenic deposits by leaching metals is proposed as an important direction of rational use of subsurface resources. The development of an algorithm for controlling the process of leaching non-ferrous metals from substandard raw materials is a tool for compensating losses of valuable and scarce raw materials allowed in the technological chain. Aspects of the mechanochemical technology of extracting metals to obtain an ecological and economic effect and radical hardening of the mineral and raw material base of mining have been studied.
Analysis of the technology for increasing the recovery and intensification of hydrocarbon production
Authors: Bosikov I I , Egorova E V , Rapatskaya L A
Published: May 2022

The analysis and improvement of the method of additional stimulation of horizontal wells – carrying out multi-zone hydraulic fracturing, which allows to significantly increase the productivity of the well, increase the drainage area, which is especially important in formations with low permeability. In this paper, the oil recovery methods used at the Yuzhnoye field, the method of modeling hydraulic fracturing were considered, and hydraulic fracturing of a highly permeable formation was simulated for two wells 1 and 3 (double-wellbore) in this field. The optimization of the hydraulic fracture design is aimed at creating a fracture of maximum conductivity and minimum length. Since neocom is a highly permeable formation, the TSO (tipscreenout) technology is proposed for hydraulic fracturing – this is end screening. This TSO technology is successfully applied at the Prudhoe Bay field (USA), in the Gulf of Mexico, Indonesia, the North Sea, Canada, Brazil, Venezuela, Vietnam, Saudi Arabia. In Russia, an example of successful design and execution is the hydraulic fracturing operation with TSO in well 4370 of the Muravlenkovskoye field, Noyabrskneftegaz company. The hydraulic fracturing method will increase the vertical permeability and unite the disparate parts of the reservoir, which will make it possible to more efficiently develop the reserves of the Neocomian deposits in the field, system for electricity consumption for the purpose of short-term forecasting of electricity consumption.
The combining different-scale studies in a reservoir simulation model of a deposit with a fractured-cavernous type of carbonate reservoir
Authors: Beltiukov D A , Kochnev A A , Galkin S V
Published: May 2022

When constructing reservoir simulation models of complex reservoirs, it is necessary to take into account the zonal heterogeneity of the filtration and reservoir properties and the influence of secondary processes on the filtration characteristics of the deposit. The underestimation of complex mining and geological conditions negatively affects the forecast for technological and economic indicators of the field development. The paper presents an approach to creating a reservoir simulation model of a complex reservoir based on the integration of different-scale research that allow us to judge the alternation of different types of reservoirs along the lateral and vertical lines. As a result, a refined reservoir permeability cube is constructed which allows us to take into account the influence of the fracturing and cavernous reservoir on the technological indicators of development.
Prospects for waste-free utilization of ore dressing tailings
Authors: Golik V I , Turluev R R , Alpeisov A T
Published: May 2022

The information about the state of the use of natural resources in Russia is given and the need to search for new sources of raw materials for industry is justified. There is a tendency to reduce the production capacity and the rate of extraction of metal ores, which does not allow the use of the infrastructure of mining enterprises and creates the problem of processing substandard ore deposits and disposal of accumulated waste. The concept of deep processing of substandard metal-containing raw materials and a strategy for the survival of mining enterprises, including the use of metal leaching technologies, is formulated. The advantages of technologies with the leaching of metals from mineral raw materials at the stages of its processing are characterized. The advantages of leaching in disintegrators are shown by comparison with the indicators of the basic variant. It is noted that mechanochemical activation improves the quality of concretes made on the basis of recycled tailings. Managing the properties of recyclable materials allows you to implement the principles of resource conservation with an economic effect. It is concluded that the recommended technology is the real direction of technological modification of production.
Improving the efficiency of exploration and development of oil and gas fields in the conditions of frequently interbedding rocks
Authors: Minnivaleev T N , Nosirov D Sh , Kuleshova L S , Minnivaleev A N , Gizzatullina A A
Published: May 2022

Exploration and development of mineral deposits largely affects the dynamics of development of the oil and gas industry in the country. An important stage in the field development is the design of technologies for constructing wells, and the drilling process itself. The appropriate modes and drilling tools create conditions for the maximum oil recovery. In this paper, based on the analysis of existing well drilling technologies and features of the mining and geological conditions of the fields, the use of a new technological solution is substantiated and recommendations are given for its implementation in the Yuzhno-Priobskoye field. The feature of the Yuzhno-Priobskoye field is frequent interbedding, that is, alternation of some rock layers by others. These layers exhibit different mechanical properties, such as hardness, elasticity, and abrasiveness, which arise certain difficulties in the field exploration and development. The proposed technological solution significantly increases the efficiency of mining and geological operations.
Description and prospects of oil and gas potential of the Middle Devonian – Lower Frasnian complex of the south-east of the Timan-Pechora province
Authors: Kuznetsova E A
Published: May 2022

The article is devoted to the assessment of the petroleum potential of the deep Middle Devonian – Lower Frasnian oil and gas complex in the south-east of the Timan-Pechora oil and gas province. Within the Verkhnepechorskaya depression of the Pre-Ural foredeep and in the south of the Pechora-Kolvinsky aulakogen, several wells were drilled with a depth of more than 5 km, some of which opened deposits of the Lower Paleozoic. These strata are difficult to access and poorly studied, and the prospects for their oil and gas potential are unclear. The article describes the composition of the complex, gives geochemical characteristics, describes reservoir properties, and presents the results of 1 and 2D basin modeling. Models of the zoning of catagenesis are presented. The oil and gas complex includes a variety of oil and gas source rocks. It is possible to allocate collectors, as well as seals. In the Middle Devonian – Lower Frasnian sediments, the processes of oil, gas and gas condensate generation took place, which could ensure the formation of deposits both in the deep strata of the Middle Paleozoic, and in the overlying horizons. The generation and accumulation of hydrocarbons in deep-buried sediments occurred at a favorable time for the formation of deposits.
Comprehensive approach to carbonate rocks typing based on core laboratory experiments data
Authors: Raznitsyn A V , Putilov I S , Melkishev O A
Published: May 2022

The paper presents results of the comprehensive approach to identification of complicated carbonate rocks types. The subject of research is the Mishrif formation core from one of the Mesopotamian oil-and-gas province field wells. At the first stage the 3 lithological petrophysical rocks types were identified based on core nuclear magnetic resonance experiments taking into account structural features, which are determined with description data of thin sections. At the second stage the 5 petrophysical rocks types were identified based on routine and special core analyses taking into account secondary changes influence, which is determined by thin sections description data. The identified petrophysical rocks types were described in detail, linear discriminant functions were deduced. These functions allow predicting the identified petrophysical types with the suggested parameters. Comparison of the lithological petrophysical and petrophysical types has shown that the pore space structure of the studied deposits depended on two factors: the first is structural features and the second is postdepositional alterations.
Investigation and analysis of cement slurries
Authors: Shemelina O N , Ovchinnikov V P , Shemelin S S , Dolgova U V , Pavelyeva Yu N , Minchenko Yu S
Published: May 2022

Laboratory studies of grouting slurries and cement compositions corresponding to specific mining and geological conditions are an important link in the design and construction of wells. In this work, a study of the rheological and physical-mechanical properties of cement grouting mixture and grouting cements was carried out. In the research for laboratory tests, samples of ground-bed mortars “GranTSEM - 7 BG” and “CemFrost”, “CemFrost Lite - 5” were used. For the qualitative process of cementing, the analysis of grouting slurries was carried out with the study of changes in the consistencies of grouting slurries over time. Thus, the acceleration of the process of drilling observation and production wells depends on the correct selected cement slurry. As a result, of the studies carried out, it was revealed that the introduction of additives into the cement slurry that bind the barrier water and the drilling fluid helps to reduce fluid loss and increases the specific surface area, which speeds up the drilling process.
Assessment of the impact of geological and production parameters on the effectiveness of acid fracturing in the fields with carbonate reservoirs
Authors: Voronova E V , Petrova L V , Gutorov A Yu
Published: May 2022

A number of different geological and production parameters affecting successful acid fracturing are considered in the conditions of carbonate reservoirs of oil fields in Bashkortostan. The study results are of use for assessing the effectiveness of geological and technical measures and for a more reasonable choice of candidate wells for acid fracturing.
Laboratory experiments on oil displacement using complexes based on enzyme solutions on a reservoir model
Authors: Veliev E M , Mukhametshin V V , Kuleshova L S , Veliev M M , Shchetnikov V I , Thanh Vu Viet , Samigullina L Z
Published: May 2022

It is shown that the oil recovery of all tested samples increases after treatment with the enzyme solution; the oil displacement coefficient varies within 7.23 – 10.59%. The change in values is associated with various characteristics of core samples in terms of porosity, permeability, initial oil saturation, as well as lithological composition. The model clearly demonstrates that the differential pressure decreases after enzyme solution treatment. This indicates that the presence of the enzyme solution changes the wettability of oil with oil-bearing rock. Oil is easily displaced from the core sample and, therefore, the permeability of the core sample increases. The outcomes of studying water permeability of core samples before and after injection of the enzyme solution reveal that the sample permeability increases when using the enzyme solution (the recovery coefficient of the core sample permeability is 1.34-1.68).
Determination of cutting process parameters for tooth of excavator active bucket
Authors: Muravskiy A K
Published: May 2022

Excavators with the active buckets are able to produce digging frozen, durable soils and hard rocks. The widespread introduction of active buckets is constrained by a number of reasons, including an incomplete theoretical description of the active bucket operation and the process of interaction of the active bucket with soil and rock. In this work, the absolute speed of movement of the cutting edge of the tooth, the cutting angle and the clearance angle of cutting are mathematically determined.
The role of deep faults in the structure formation of the TCFD, the distribution of hydrocarbon accumulations, and thermomineral sources
Authors: Daykaev A A , Abubakarova E A , Elzhaev A S , Khasanov M A , Ezirbaev T B , Germakhanova D U , Alieva Kh A , Shaipova A A
Published: May 2022

The work purpose was to assess the prospects of oil and gas potential of the western part of the Tersko-Caspian trough (TCT) concerning the development of deep-sunk areas in the light of modern ideas about the deep-seated formation of hydrocarbons. The main tasks are to analyze the ideas about the formation mechanism of the tectonic structure and formation of hydrocarbon accumulations; to study the relationships between the formation processes, migration, and the areal distribution of hydrocarbon accumulations; to determine the main prerequisites for the deep genesis of oil and gas. The scientific novelty lies in a comprehensive approach to the study of the formation processes of hydrocarbons, migration, the formation of traps, and patterns of placement of hydrocarbon accumulations. The article describes the mechanisms of formation of the Tersk and Sunzha composite anticline as the main zones of oil and gas accumulation. It is suggested that the formation of high-amplitude anticline folds in the upper cretaceous deposits resulted from the vertical migration of high-pressure fluids along deep faults with the breakthrough of their upper horizons of the sedimentary cover into the late-orogenic folding stages. The main prerequisites for the deep genesis of oil and gas are listed as pronounced uneven distribution of hydrocarbon accumulations, AHFP, hydrochemical anomalies, etc.
Results of identification of ineffective oil objects in carbonate reservoirs
Authors: Grezina O A
Published: May 2022

The article presents data on the selection of oil analogous objects using multidimensional exploration analysis of geological and physical parameters. The main components and ineffective objects in the carbonate reservoirs of the Tournaisian stage confined to tectonic elements within the inner and outer zones of the Cis-Ural passive margin of the East European paleocontinent were analyzed. The study showed that the use of codes of the tectonic elements to which the facilities belong as a grouping variable makes it possible to identify groups with common characteristics. It is recommended to apply the successful experience of stimulating oil production by acid-implosion in the wells of the Tournaisian stage of the Almetyevsk peak field to the facilities of the same and adjacent (Belebeevsko-Shkapovskaya peak) groups with close axe coordinates for the main components.
The influence of reservoir rock fractures on the efficiency of geotechnical jobs on the Yamal oilfields
Authors: Sharapov A S
Published: May 2022

At present, the majority of Yamal oilfields are characterized by low debits. That is why geotechnical jobs (GTJ) are conducted here to increase oil production. Thus, this article analyzes predicted and actual efficiency of GTJ on nineteen Yamal oilfields in 2010-2017. Therefore, the purpose of the article is to provide information on the quantity and efficiency of GTJ on Yamal oilfields as well as to interpret the results obtained. The question is how reservoir rock fractures influence GTJ. So, much attention is given to the efficiency of hydraulic fracturing operation (HFO) in relation to the rate of field tectonical diversity. In fact, our analysis shows that physical and chemical methods take the leading place among the quantity of actual operations. It was also found that the biggest incremental oil production was obtained from drilling horizontal drain holes, but the smallest quantity – from remedial cementing. Furthermore, the results presented here show the dependence of HFO efficiency on the rate of field diversity. In conclusion, actual data prove that double permeability of reservoir rock increases the efficiency of well perforation, HFO and physical and chemical methods as well as its dependence on the rate of field diversity. The findings are of direct practical relevance.
Gas content and gas-dynamic characteristics of rocks of the IV-p horizon of the Starobin deposit of potash salts
Authors: Bobrov D A , Litvinovskaya N A , Nesterov E A
Published: May 2022

The article presents the results of studies of the gas content and gas-dynamic characteristics of the free gas contained in the salt rocks of the IV ℃ p horizon of the Starobin deposit of potash salts. The research was carried out in the workings of the Petrikovsky ore enrichment plant. The IV-p horizon was discovered for the first time and data on the content of free gas in the rocks have not existed until now. Given that mining operations in other potash horizons and areas of the field are regularly accompanied by various gas-dynamic phenomena, all commissioned horizons and new areas should be examined for the content of free gas in the rocks and at the rock contacts. For the research, mine instrumental observations were used according to the methodology developed at the Mining Institute of the Ural Branch of the Russian Academy of Sciences. The obtained data serve as the basis for the development of recommendations for the safe conduct of mining operations in the rocks of the IV – p horizon.
The comparison of methods for modeling seismic impact on buildings and structures
Authors: Kravchenko G M , Trufanova E V , Mazhiev K Kh , Mazhiev Adam Kh , Mazhiev Aslan Kh , Mazhieva A Kh
Published: May 2022

The article compares methods for modeling seismic effects on buildings and structures to improve the structural safety of design solutions. A linear-spectral method of accounting for seismic impact and an integral model are considered. Seismic loads are determined along the main axes of the building under study, taking into account translational and rotational effects. The orientation of the cosines of the seismic impact on the building is calculated. The assessment of participation factors for each form of natural fluctuations is carried out. Combinations of seismic loads are compiled, their influence on the stress-strain state of the building frame structures is analyzed. Recommendations for modeling the seismic impact on buildings and structures by the finite element method have been developed. The proposed algorithm for modeling seismic effects by the finite element method allows determining the most dangerous propagation of seismic effects in accordance with the modal analysis of the frame of a multi-storey building.
Initial strength analysis of reinforced concrete monolithic supports for spherical and cylindrical mine workings
Authors: Zaitsev A V , Kutergin A V , Fukalov A A , Votinov A S , Kolytchev I Yu
Published: May 2022

By using decomposition of hoop and radial components of the displacement vector to the trigonometrical and generalized power series, we obtained the new exact analytical solutions to problems of the equilibrium state of thick-walled heavy anisotropic central-and axial-symmetric bodies fixed on their external surfaces and subject to uniform internal lateral pressure. The estimation of an initial strength of cylindrical and spherical reinforced concrete monolithic mine working supports for a long-term storage of gas and oil is carried out on the basis of a multicriteria approach taking into account real damage mechanisms. They include damage from tension or compression in radial, hoop and axial directions, and from transversal and antiplane shear) of anisotropic axial- and central-symmetric bodies.
Assessment of the fracture stress of clay-carbonate rocks of the Vereiskian reservoir for oil fields in the Perm region
Authors: Votinov A S , Zaitsev A V , Rozhkova Yu A , Osovetsky B M , Seredin V V
Published: May 2022

Currently, one of the most effective stimulating oil production methods from the Vereiskian production zones of oil fields in Perm Krai is proppant hydraulic fracturing (PHF). The effectiveness of the method largely depends on the geometric dimensions of the fracture and the optimal distribution of the proppant in it. The mudstones of the Vereiskian stage limit the growth of the fracture in height, but in certain cases its can be broken in the course of hydraulic fracturing. In this regard, the determination of the conditions for their fracturing is an urgent and important task. In the absence of rock samples of proper quality, the chemical composition of mudstones was determined during the study. The obtained results are compared with the existing data on the minerals of the montmorillonite group of clays. To determine the parameters of the ultimate stress state of the formation, a Mohr’s circle of stress is constructed using the known values of the compressive stress and the angle of internal friction of the clays. As a result, the fracture stress of mudstones is obtained, which is in the range of bottom-hole pressures during hydraulic fracturing, that is, there is a possibility of fracture growth outside the target interval.
Improving the technology of opening productive layers to boost the productivity of exploration and production wells
Authors: Chizhov A P , Andreev V E , Kuleshova L S , Mukhametshin V V , Andreev A V , Chibisov A V
Published: May 2022

The article describes the results of improving the well construction completion technology. The factors and processes decreasing technological indicators of new exploration and production wells are analyzed. Research is based on systemic approaches to solving complex scientific and technical problems. The parameters of implementation of the improved technology are presented. The results of field trials intended to implement the technology in the construction of wells in Russian regions are analyzed.
Experience of applying the shock wave impact method for the bottomhole zone
Authors: Khusnutdinova R R , Petrova L V , Yusupova L F , Gilyazetdinov R A
Published: May 2022

Improving the processes of exploration and development of fields, as well as increasing the productivity of oil reserves using physicochemical methods are one of the main tasks in stabilizing oil recovery and increasing the oil recovery factor. The most rational method used for hard-to-recover reserves is the shock-wave impact technology. This method can stimulate the release of energy from anomalously stressed zones and intensify the influx of hydrocarbons from deep layers of the Earth along the tectonic faults and sub-vertical inversion ring structures. The article presents the results of a study of the shock-wave impact on production wells of the Sabanchinskoye field and discusses factors that reduce the profitability of this technology.
Temperature-baric behavior of the effective thermal conductivity of sandstones
Authors: Emirov S N , Aliverdiev A A , Aliev R M , Beybalaev V D , Ramazanova E N , Amirova AA
Published: May 2022

The paper presents the results of measurements of the effective thermal conductivity of three sandstone samples exhibiting different structural ordering in the temperature range 273-523 K and pressures from atmospheric to 400 MPa, as well as (2) a low-parameter model, described as a temperature dependence at a fixed pressure and the pressure dependence at a fixed temperature. It also describes the influence of pressure on the nature of the temperature dependence. The samples from the following deposits were studied: (1) Kochubei, the Republic of Dagestan, (2) Buinaksk, the Republic of Dagestan, and (3) the Tyumen superdeep well. It was shown that the cumulative increase in temperature and pressure for sandstones with different structural ordering (even when the absolute values of the effective thermal conductivity at atmospheric pressure and room temperature are close) can have a qualitative difference and with a predominantly amorphous ordering, it must be taken into account when compiling temperature models in the terrestrial bark.
Turbulent drag reduction by spanwise slot blowing pulsed plasma actuation
Authors: ZHENG Borui , JIN Yuanzhong , YU Minghao , LI Yueqiang , WU Bin , CHEN Quanlong
Published: May 2022

This work studies the turbulent drag reduction (TDR) effect of a flat plate model using a spanwise slot blowing pulsed plasma actuator (SBP-PA). Wind tunnel experiments are carried out under a Reynolds number of 1.445 × 104. Using a hot-wire anemometer and an electrical data acquisition system, the influences of millisecond pulsed plasma actuation with different burst frequencies and duty cycles on the microscale coherent structures near the wall of the turbulent boundary layer (TBL) are studied. The experimental results show that the SBP-PA can effectively reduce the frictional drag of the TBL. When the duty cycle exceeds 30%, the TDR rate is greater than 11%, and the optimal drag reduction rate of 13.69% is obtained at a duty cycle of 50%. Furthermore, optimizing the electrical parameters reveals that increasing the burst frequency significantly reduces the velocity distribution in the logarithmic region of the TBL. When the normalized burst frequency reaches f
+ = 2π
f
p
d/U
∞ = 7.196, the optimal TDR effectiveness is 16.97%, indicating a resonance phenomenon between the pulsed plasma actuation and the microscale coherent structures near the wall. Therefore, reasonably selecting the electrical parameters of the plasma actuator is expected to significantly improve the TDR effect.
Classification of steel based on laser-induced breakdown spectroscopy combined with restricted Boltzmann machine and support vector machine
Authors: ZENG Qingdong , CHEN Guanghui , LI Wenxin , LI Zitao , TONG Juhong , YUAN Mengtian , WANG Boyun , MA Honghua , LIU Yang , GUO Lianbo , YU Huaqing
Published: May 2022

In recent years, a laser-induced breakdown spectrometer (LIBS) combined with machine learning has been widely developed for steel classification. However, the much redundant information of LIBS spectra increases the computation complexity for classification. In this work, restricted Boltzmann machines (RBM) and principal component analysis (PCA) were used for dimension reduction of datasets, respectively. Then, a support vector machine (SVM) was adopted to process feature information. Two models (RBM-SVM and PCA-SVM) are compared in terms of performance. After optimization, the accuracy of the RBM-SVM model can achieve 100%, and the maximum dimension reduction time is 33.18 s, which is nearly half of that of the PCA model (53.19 s). These results preliminarily indicate that LIBS combined with RBM-SVM has great potential in the real-time classification of steel.
Thermodynamics and optimal protocols of multidimensional quadratic Brownian systems
Authors: Abiuso Paolo , Holubec Viktor , Anders Janet , Ye Zhuolin , Cerisola Federico , Perarnau-Llobet Martí
Published: May 2022

We characterize finite-time thermodynamic processes of multidimensional quadratic overdamped systems. Analytic expressions are provided for heat, work, and dissipation for any evolution of the system covariance matrix. The Bures-Wasserstein metric between covariance matrices naturally emerges as the local quantifier of dissipation. General principles of how to apply these geometric tools to identify optimal protocols are discussed. Focusing on the relevant slow-driving limit, we show how these results can be used to analyze cases in which the experimental control over the system is partial.
A rolling bearing status monitoring method based on subband spectral fuzzy description
Authors: Harhoud Brahim , Ramdani Messaoud , Lachouri Abderrazak , Bekaik Mounir
Published: May 2022

Vibration signals provided by rotating machinery are informative signals about their operating states. By nature, the vibration signal behavior is non-stationary. To this end, the extraction of discriminating and fault-sensitive parameters is a major challenge in the field of monitoring rotating machines. Conventional fault diagnosis methods based on signal processing use statistical feature parameters in time domain, frequency domain and time-frequency representation. In this article, a new method is proposed for the detection and classification of bearing defects based on spectral subband using frequency membership functions. Statistical parameters including subband energy, Center frequency, root variance frequency and Shannon entropy are considered. Compared to the common features, the extracted parameters can provide discriminating information. These feature parameters are finally fed into a generalized RBF neural network system trained with the Resilient Backpropagation (Rprop) algorithm to classify seven pre-established fault types in ball bearings operating under multiple shaft speeds and load conditions. The results suggest that the proposed system can significantly improve the diagnostic performance in terms of accuracy and estimation of the bearing fault level.
NO2 sensing with CdS nanowires at room temperature under green light illumination
Authors: Li Peipei , Jin Hongqiang , Yu Jia , Chen Weiming , Zhao Runqing , Cao Changyan , Song Weiguo
Published: May 2022

Detection of ppb-level NO2 gas under atmosphere is urgent to meet the requirements of the rapidly developing internet of things. Compared with traditional sensing methods, light illumination has been considered as a key approach for excellent gas sensor performance under moderate conditions. Herein, we developed a green-light-assisted gas sensor based on cadmium sulfide nanowires (CdS NWs) that has good NO2 sensing capability at ambient temperature. The response values of NO2 are 236% and 11% to 10 ppm and 12.5 ppb, respectively. Furthermore, the CdS NWs sensor has a high selectivity for NO2 over a variety of interference gases, as well as good stability. The cleaning light activation and the sulfur vacancy-trapped charge behavior of CdS NWs are observed, which suggest a light-assisted sensing mechanism. These results suggest that light-induced charge separation behavior might significantly improve gas-sensing characteristics.
Clinical Use of Extracellular Vesicles in the Management of Male and Female Pattern Hair Loss: A Preliminary Retrospective Institutional Review Board Safety and Efficacy Study
Authors: Sasaki Gordon H
Published: May 2022

Background

Pattern hair loss is a common disorder in female and male patients.

Objectives

To assess the safety, efficacy, and satisfaction of a single extracellular vesicle (EV) treatment over 6 months.

Methods

A retrospective open-label study among 22 female and 9 male patients who demonstrated early stages of alopecia or were in remission from previous medical and surgical treatments. The amount of undiluted or diluted volumes of EV solution used was determined by the extent and degree of alopecia. Global photography, Patient Global Aesthetic Improvement Scale (PGAIS) and Investigator Global Aesthetic Improvement Scale (IGAIS) questionnaires, and trichoscan measurements were compared at baseline and 6 months in 3 response categories.

Results

Frequent growth responses were observed: older aged females and younger aged males, shorter history of alopecia, earlier stages of hair loss, larger and undiluted volumes of XoFlo, previous positive responses to medical and surgical treatments, and absence or control of disease factors affecting the hair. Global photography, trichoscan for density, follicle diameter, terminal: vellus ratio, and PGAIS/IGAIS satisfaction questionnaires at baseline and 6 months were useful in assessing clinical efficacy. No significant adverse reactions were observed.

Conclusions

Intradermal injections with varying doses of EVs were safe and effective among indicated alopecic female and male patients. Findings suggest that the presence of positive factors, absence of conditions known to negatively affect hair growth, and administration of larger volumes of XoFlo may have a significant influence on the use of this new cell-free therapy.

Level of Evidence: 4
ExplorATE: a new pipeline to explore active transposable elements from RNA-seq data
Authors: Femenias Martin M , Santos Juan C , Sites Jack W , Avila Luciano J , Morando Mariana
Published: May 2022

Motivation

Transposable elements (TEs) are ubiquitous in genomes and many remain active. TEs comprise an important fraction of the transcriptomes with potential effects on the host genome, either by generating deleterious mutations or promoting evolutionary novelties. However, their functional study is limited by the difficulty in their identification and quantification, particularly in non-model organisms.

Results

We developed a new pipeline [explore active transposable elements (ExplorATE)] implemented in R and bash that allows the quantification of active TEs in both model and non-model organisms. ExplorATE creates TE-specific indexes and uses the Selective Alignment (SA) to filter out co-transcribed transposons within genes based on alignment scores. Moreover, our software incorporates a Wicker-like criteria to refine a set of target TEs and avoid spurious mapping. Based on simulated and real data, we show that the SA strategy adopted by ExplorATE achieved better estimates of non-co-transcribed elements than other available alignment-based or mapping-based software. ExplorATE results showed high congruence with alignment-based tools with and without a reference genome, yet ExplorATE required less execution time. Likewise, ExplorATE expands and complements most previous TE analyses by incorporating the co-transcription and multi-mapping effects during quantification, and provides a seamless integration with other downstream tools within the R environment.

Availability and implementation

Source code is available at https://github.com/FemeniasM/ExplorATEproject and https://github.com/FemeniasM/ExplorATE_shell_script. Data available on request.

Supplementary information

Supplementary data are available at Bioinformatics online.
Associations of lung cancer risk with biomarkers of Helicobacter pylori infection
Authors: Yoon Hyung-Suk , Shu Xiao-Ou , Cai Hui , Zheng Wei , Wu Jie , Wen Wanqing , Courtney Regina , Shidal Chris , Waterboer Tim , Blot William J , Cai Qiuyin
Published: May 2022

Helicobacter pylori infection has been suggested to be associated with lung cancer risk. However, information is lacking on whether the association differs by H. pylori antigen. We conducted a nested case-control study within the Southern Community Cohort Study, including 295 incident lung cancer cases and 295 controls. Helicobacter pylori multiplex serology assay was performed to detect antibodies to 15 H. pylori proteins. Conditional logistic regression was used to estimate odds ratios (ORs) and confidence intervals (95% CIs) after adjustment for covariates. Overall H. pylori+ was associated with a non-statistically significant increased risk of lung cancer (OR: 1.29; 95% CI: 0.85–1.95). Significant associations, however, were observed for H. pylori+ VacA+ (OR: 1.64; 95% CI: 1.02–2.62) and H. pylori+ Catalase+ (OR: 1.75; 95% CI: 1.11–2.77). The positive association of H. pylori+ Catalase+ with lung cancer risk was predominantly seen among African Americans (OR: 2.09; 95% CI: 1.11–3.95) but not European Americans (OR: 1.20; 95% CI: 0.56–2.54). Among participants who smoked ≥ 30 pack-years, overall H. pylori+ (OR: 1.85; 95% CI: 1.02–3.35), H. pylori+ CagA+ (OR: 2.77; 95% CI: 1.35–5.70), H. pylori+ VacA+ (OR: 2.53; 95% CI: 1.25–5.13) and H. pylori+ HP1564+ (OR: 2.01; 95% CI: 1.07–3.77) were associated with increased risk of lung cancer. Our study provides novel evidence that associations of H. pylori infection with lung cancer risk differ by H. pylori biomarker, may be more evident among African Americans and may be modified by smoking habits. Furthermore, studies are warranted to confirm our findings.
Paving the Way Towards Precision Vaccinology: The Paradigm of Myocarditis After Coronavirus Disease 2019 (COVID-19) Vaccination
Authors: Lagousi Theano , Papadatou Ioanna , Strempas Petros , Chatzikalil Elena , Spoulou Vana
Published: May 2022

Systems vaccinology approaches have introduced novel tools for the evaluation of the safety profile of novel vaccine antigens by developing biomarkers of vaccine reactogenicity associated with potential adverse events. The use of such approaches may prove extremely advantageous in the context of a global pandemic where accelerated approval of new vaccine formulations for all ages is essential for the containment of the epidemic. The spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has had devastating effects on global health, but the emergency authorization of mRNA vaccines significantly reduced SARS-CoV-2–associated morbidity and mortality. Despite their favorable safety profile in adult populations, recent reports have raised concerns about an association of the mRNA-based vaccines with acute myocarditis, predominantly among male adolescents and young adults following the second vaccine dose. Here, we review data on myocarditis epidemiology following SARS-CoV-2 mRNA vaccination and describe potential mechanisms involved that may explain the sex- and age-related differences, focusing on mRNA immune reactivity. The case of vaccine-associated myocarditis highlights the need to incorporate precision vaccinology approaches for the development of safe and effective vaccines for everyone.
How Drivers of Seasonality in Respiratory Infections May Impact Vaccine Strategy: A Case Study in How Coronavirus Disease 2019 (COVID-19) May Help Us Solve One of Influenza’s Biggest Challenges
Authors: Lofgren Eric T , Naumova Elena N , Gorski Jack , Naumov Yuri , Fefferman Nina H
Published: May 2022

Vaccines against seasonal infections like influenza offer a recurring testbed, encompassing challenges in design, implementation, and uptake to combat a both familiar and ever-shifting threat. One of the pervading mysteries of influenza epidemiology is what causes the distinctive seasonal outbreak pattern. Proposed theories each suggest different paths forward in being able to tailor precision vaccines and/or deploy them most effectively. One of the greatest challenges in contrasting and supporting these theories is, of course, that there is no means by which to actually test them. In this communication we revisit theories and explore how the ongoing coronavirus disease 2019 (COVID-19) pandemic might provide a unique opportunity to better understand the global circulation of respiratory infections. We discuss how vaccine strategies may be targeted and improved by both isolating drivers and understanding the immunological consequences of seasonality, and how these insights about influenza vaccines may generalize to vaccines for other seasonal respiratory infections.
Constitutive expression of the global regulator AbrB restores the growth defect of a genome-reduced Bacillus subtilis strain and improves its metabolite production
Authors: Yamamoto Junya , Chumsakul Onuma , Toya Yoshihiro , Morimoto Takuya , Liu Shenghao , Masuda Kenta , Kageyama Yasushi , Hirasawa Takashi , Matsuda Fumio , Ogasawara Naotake , Shimizu Hiroshi , Yoshida Ken-ichi , Oshima Taku , Ishikawa Shu
Published: May 2022

Partial bacterial genome reduction by genome engineering can improve the productivity of various metabolites, possibly via deletion of non-essential genome regions involved in undesirable metabolic pathways competing with pathways for the desired end products. However, such reduction may cause growth defects. Genome reduction of Bacillus subtilis MGB874 increases the productivity of cellulases and proteases but reduces their growth rate. Here, we show that this growth defect could be restored by silencing redundant or less important genes affecting exponential growth by manipulating the global transcription factor AbrB. Comparative transcriptome analysis revealed that AbrB-regulated genes were upregulated and those involved in central metabolic pathway and synthetic pathways of amino acids and purine/pyrimidine nucleotides were downregulated in MGB874 compared with the wild-type strain, which we speculated were the cause of the growth defects. By constitutively expressing high levels of AbrB, AbrB regulon genes were repressed, while glycolytic flux increased, thereby restoring the growth rate to wild-type levels. This manipulation also enhanced the productivity of metabolites including γ-polyglutamic acid. This study provides the first evidence that undesired features induced by genome reduction can be relieved, at least partly, by manipulating a global transcription regulation system. A similar strategy could be applied to other genome engineering-based challenges aiming toward efficient material production in bacteria.
Syncope in a pregnant woman with repaired Tetralogy of Fallot: a case report
Authors: Ghazaryan Nare , Adamyan Miqayel , Khachatryan Lianna , Hovakimyan Tatevik
Published: May 2022

Background

Tetralogy of Fallot (TOF) is one of the most widespread cyanotic congenital heart disease (CHD), which can be successfully repaired in the neonatal period. However, residual problems and the surgical technique itself can create a favourable basis for arrhythmias and conduction abnormalities in these patients. Sometimes, these arrhythmias may worsen during pregnancy and require urgent intervention.

Case summary

This is a case of a 25-year-old woman, who underwent a surgical repair of TOF at the age of 2 years. She suffered an ischaemic stroke postoperatively, which was complicated with secondary seizures and syncope. These episodes were evaluated as epilepsy. The patient was admitted to our hospital with the above-mentioned complaints in the 10th week of pregnancy. A comprehensive cardiac examination was performed. Her presyncopal event was captured during Holter monitoring, which documented a severe dysfunction of the sinus node. She was diagnosed with postoperative sick sinus syndrome and implanted with a permanent dual-chamber pacemaker (PM). After the operation, the patient did not have any episodes of syncope or seizures and the PM check-up showed almost 30% of atrial pacing.

Conclusion

No matter how obvious the neurological or other nature of syncope may seem, it is advised to exclude the cardiac origin of syncope, especially in patients with repaired CHD. One of the most common complications after surgery of CHD is rhythm and conduction disturbances. In some of these cases, permanent PM implantation can be unavoidable, even during pregnancy. The implantation of the PM device during pregnancy can be performed safely.