bluuebunny/crossref_metadata_2025 huggingface dataset:
Relationship of precipitation intensity in the form of snow with atmospheric electricity and radiothermal radiation of the snow cover
Authors: Kozlov Alexey , Kazantsev Vyacheslav
Published: May 2024

Remote radiophysical methods using artificial satellites of the Earth allow to determine physical and chemical parameters of the atmosphere. For this purpose, calibration subsatellite measurements are necessary. One of the natural phenomena to be studied is precipitation in the form of snow. This paper presents the results of ground-based measurements of radio-thermal radiation of snow cover at two wavelengths 0.88 cm and 1.35 cm, as well as the results of measurements of the variation of the vertical component of the surface atmospheric electric field strength during snowfall. The measurements were made near the ice-water phase transition temperature. The research site is located in the city of Chita (Russian Federation). A strong influence of air temperature on the measured values, especially at the ice-water phase transition temperature, was found.
Study of the characteristics of organic mining materials affecting their explosive properties
Authors: Skripnik Igor , Kaverzneva Tatyana , Ivakhnyuk Sergey , Savelev Dmitry , Panov Sergey , Kriklivyy Sergey
Published: May 2024

The article analyzes the explosive and fire-hazardous properties of coal dust of various dispersions using the example of coal mine dust. The authors proposed sample preparation methods for obtaining and studying dust fractions with a dispersity of less than 800 microns. The results of a study of the shapes of dust particles are presented. To study the characteristic particle sizes the authors suggested using the optical microscopy method implemented using a LEICA DM 4000 microscope and the “Image Scope Color” information processing application. To assess the reactivity of dust particles, the authors used a simultaneous thermal analysis method implemented using an STA 449 F1 Jupiter with NETZSCH Proteus Software. The results of a thermogravimetric study of narrow fractions of organic coal dust are presented. The influence of dispersion on the explosive properties of dusts has been established. The results obtained showed the need and expediency of further study of precisely fine fractions of explosive dusts of this kind.
An integrated approach to safety in the design and operation of open-pit mining facilities
Authors: Ermakova Ekaterina , Skripnik Igor , Panov Sergey , Kaverzneva Tatyana , Gorbunova Olga , Tsimberov Dmitry
Published: May 2024

The article presents a pioneering integrated approach to assessing compliance with environmental, fire, industrial safety, and labor protection requirements in open-pit mining operations. The study was conducted at two existing open-pit mining facilities located in the Trans-Baikal Territory of the Russian Federation, analyzing the causes of injuries, statistical data, and comparing the mining technologies used. The key findings emphasize that the efficiency of deposit development and the safety of mining operations are heavily dependent on the quality of the technical design. The article also discusses software systems used for the design of mining facilities, which enable monitoring of the safety and labor protection aspects during quarry operation. The results of the comparative analysis are expected to be of interest to both quarry design specialists and the engineering and technical personnel of existing open-pit mining facilities. This integrated approach represents a significant advancement in the field, providing a comprehensive framework for enhancing safety and operational efficiency in the mining industry.
Extraction of copper from copper processing plant waste by leaching
Authors: Mirzajanova Saodat , Saidova Malika , Beknazarova Gulnoza , Tukhtamurodov Farrukh , Choriyev Hikmatulla
Published: May 2024

On the territory of Uzbekistan, copper is mainly found in chalcopyrite’s and chalcocite’s, the enrichment of copper minerals results in waste and tailings as a result of technological processing. The processes of copper processing plants are complex and are constantly characterized by gradual technological processes. The technology of ore enrichment in its initial state can be enriched in several stages: grinding and crushing, flotation processes, gravitational methods, magnetic separation methods. As a result of technological processes, waste and tailings are formed, i.e. they are very poor and unsuitable for the recycling process. And these wastes harm the environment, accumulate and occupy large areas. An effective technology for extracting metals from waste is the process of leaching in the dump, and the ratio of leaching of sulfuric acid with tailings corresponds according to the technological scheme, that is, T : W = 1 : 15; 1 : 10; 1 : 7,5. The tail analysis was studied, which has a copper content of 0.534%, conducted by experiment after leaching, the amount of copper in the solution formed 1.66%. The copper in the solution turned into a solution 3 times more than in its original form.
Spectroscopic and thermal studies of mixed ligand coordination compounds of cobalt (II) with aspartic and dicarboxylic acids
Authors: Khusenov Kakhramon , Zayniddinova Gulchehra , Aliev Togaymurot , Karimov Zokir
Published: May 2024

The synthesis of complex compounds of cobalt (II) ion in the presence of aspartic and dicarboxylic acids has been studied by thermal and spectroscopic methods. Thermal decomposition processes of these compounds are studied on the basis of thermal analysis, and endo- and exoeffects are determined. The decomposition products of the compounds were studied on the basis of mass reduction by the thermogravimetric method. Based on the results of spectroscopic studies, the structural formulas of the synthesized coordination compounds are established.
Assessment of the quality of electricity by applying reactive power sources
Authors: Togayev Islom , Tovbaev Akram , Nodirov Gulom
Published: May 2024

In the quest to enhance electricity quality, various states and parameters play crucial roles, particularly in assessing the significance and capabilities of reactive power sources. The evolution of electricity systems in developed nations is marked by a vigorous pursuit of cutting-edge technologies to boost energy system efficiency, lower construction and operational costs of network infrastructure, and enhance power supply reliability. The issue of reactive power compensation and electricity quality is intricately linked to diverse consumer loads, voltage, and frequency considerations. This process entails elevating the system's active power factor to harmonize total power within the AC network, maintaining voltage levels, and mitigating harmonic distortions stemming from nonlinear industrial loads. Voltage stability measures are typically essential to curtail fluctuations along power transmission lines. Enhancing the system's operational reliability involves augmenting the maximum active power that reactive power compensation mechanisms can adjust.
Sine-cosine rotating transformers in zenith angle converters
Authors: Amirov Sulton , Ataullayev Aminjon
Published: May 2024

The article proposes a principle for constructing contactless primary zenith angle converters based on sine-cosine rotating transformers. This principle involves isolating signals caused by changes in the mutual induction coefficient between the primary and secondary windings and suggests using a reference signal to establish the required functional relationship. The study revealed that errors in displaying the sine and cosine functions stem from the identical maximum inductive resistances of mutual induction, active and inductive components of the secondary load circuits, and the asymmetry of the zero points, characterized by a nonperpendicular electrical angle. It has been determined that to enhance measurement accuracy, it is essential to eliminate the reciprocity of signal phases from the parameters of signal circuits.
Application of alternative technologies in repair of rolled and welded tube to tubesheet joints
Authors: Tokarev Andrei , Karetnikov Denis , Fairushin Airat
Published: May 2024

The article proposes a technology of repair of composite (i.e. obtained by welding and expanding) tube to tubesheet joints of heatexchanging apparatuses using friction welding operations devoid of heat treatment. The objective of the investigation was to determine the influence of using the proposed technology for repairing the composite joints made of 15Cr5Mo steel on the properties of the joint. Samples made by different technologies were tested for strength and tightness. The result of the study was the confirmation of compliance of the characteristics of the samples made by the proposed technology with the samples made by the currently widely used technology utilizes arc welding.
Computational study of band gap and structural effect of doped BiVO4
Authors: Gofurov Shukur , Bozorova Dilbar , Ismailova Oksana , Kadirova Zukhra
Published: May 2024

Density functional theory calculation using Quantum Espresso package was conducted to study band gap and structural effect of BiVO4 by doping elements like Zr, Mo and S, to substitute Bi, V and O. Band gap of BiVO4 has been reduced from 2.25 to 1.54 eV by ~8% S2- substitution with O2-. Distance between atoms V-O increased by changing to V-S, which effects vibration of the atoms in the structure. ~2% substitution Mo and Zr with Bi and V changed monoclinic BiVO4 to mix phase of tetragonal scheelite phase. It has been shown that XRD powder pattern of optimized structure can show (121) plane peak shifts by doping Mo or Zr in BiVO4 lattice.
Study of the wear resistance of hardened harrows of agricultural machines
Authors: Shutkin Alexey , Ishkov Aleksey , Shmykova Polina , Kalimullin Marat , Aksenov Alexey , Sakhapov Rustem , Yakushev Adel
Published: May 2024

The conducted research is devoted to the analysis of the wear resistance of materials used in reinforcing coatings of working bodies of agricultural machines subjected to friction under abrasive action in soil conditions. The aim of the study was to determine the degree of wear of the hardened teeth of the disc under the load of their impact on the soil in real operating conditions. The disk of a toothed harrow, which is a hardened working body of agricultural machinery, was used as an object of research. The individual teeth of this disc were the test samples. To increase the wear resistance of the teeth, a variety of reinforcing coatings were applied. The results of the study made it possible to comparatively evaluate the effectiveness of various reinforcing coatings and identify their effect on the wear resistance of the teeth of the disc. This study provides important data for further improvement of materials and technologies in agricultural engineering in order to increase the durability and efficiency of working bodies.
Rheological and strength properties of dynamic loading during cutting of finished flour products
Authors: Urinov Uygun , Amonov Mahmud
Published: May 2024

This article presents the findings of scientific research on the rheological and strength properties under dynamic loading conditions when cutting finished flour products. The study explores the main rheological characteristics and technological coefficients of rye bread cutting equipment, along with the results of cutting technology for various product types under dynamic bread loading. It is observed that as the speed of bladematerial interaction increases, the viscous properties of the deformable body decrease due to the inertia of the viscous components. Structural elements undergo spontaneous reorganization at varying frequencies in response to heat, highlighting a range of frequencies that dictate the ability to reconstruct all structural elements. The utilization of thin plate-like knives in multi-knife cutting machines is discussed for their high efficiency in cutting bread and bread products, minimal contact surface area, low tooling material consumption, and promising applications.
The concept of architectural reliability of software for ensuring the functioning of request-free measuring stations
Authors: Kovalev Igor , Kovalev Dmitry , Kovalev Roman , Podoplelova Valeria , Losev Vasiliy , Voroshilova Anna , Borovinsky Dmitry , Gadoeva Mavlyuda
Published: May 2024

The article proposes the concept of architectural reliability of software included in the hardware and software complex of request-free measuring stations. This concept is based on previously completed activities to shape the appearance of a complex of hardware and software for the functioning of measuring stations. It is noted that in order to solve problems related to increasing the architectural reliability of software, the security functions and information and logical interaction of the components of the measuring station are essential. Since software architecture is determined by the concept of architectural design, the work presents the stages of designing a complex software system. The description provided includes the basic operations of architectural design, with decomposition necessary to structure and organize system specifications. The final stage lists the main steps that should be taken to enhance the strategic influence of the software architecture on the functionality and reliability of the set of technical means for ensuring the operation of request-free measuring stations.
Fuzzy-logic system for regulating the temperature regime of a bioreactor in the process of bacterial oxidation
Authors: Jumaev Odil , Makhmudov Giyosjon , Isabekova Venera , Rakhimov Anvarjon , Orziyev Jonibek
Published: May 2024

In this article, a simulation model of an intelligent control system for a bioreactor used in the bacterial oxidation process of sulfide deposits with complex, gold-enriched content is developed using the functional blocks from the Fuzzy Logic Toolbox library in the MATLAB software package. Furthermore, the mathematical model of the bioreactor is represented through its transfer function in the significant adjustment channel. A rule base is established to regulate the variation of input and output parameters for the fuzzy control system. The study reveals that employing a fuzzy controller for bioreactor systems is an effective method for system adjustment.
Enhancing abrasion resistance testing for linoleum and rubber products: A proposal for improved device operation
Authors: Jumaev Odil , Ismoilov Muhriddin , Raxmatov Doston , Qalandarov Alisher
Published: May 2024

Quality assessment of linoleum and rubber products, including abrasion resistance, is crucial for ensuring their durability and performance. However, existing testing devices may exhibit drawbacks that affect the accuracy of assessments. This article proposes a solution to enhance device operation for more precise testing results. By employing a programmable logic controller (PLC) and tachometer, the rotation speed of the drum in the testing device can be precisely controlled, addressing issues of deviation and ensuring adherence to regulatory requirements. Through an in-depth analysis, this paper evaluates the proposed solution's potential to improve the accuracy of quality assessments and enhance product quality.
Stress in the tank case at mounting displacements and loads on nozzles
Authors: Zakirnichnaya Marina M. , Rubtsov Aleksey V. , Krivenkov Igor I. , Ilyasov Vadim R. , Mustafina Eliza R.
Published: May 2024

In the practice of operating capacitive equipment, production moments often arise due to technical re-equipment and changes in the operating parameters of tanks to meet specific requirements for equipment design in the technological process. Common reconstruction activities involve modifying process nozzles in technical device housings to align with process piping project specifications. Consequently, the stressed-deformed state in vessel bodies before and after reconstruction can vary significantly. During manufacturing or repair tasks, permissible installation displacements, such as the shifting of edges in joined cylindrical shell housings, may occur within regulatory limits. This study focuses on analyzing stress variations and stress distribution zones, considering the combined effects of these factors.
Impact of various factors on the cutting performance of knives when processing food products
Authors: Urinov Nasillo F. , Dubrovets Lyudmila V.
Published: May 2024

Determining the optimal geometric and kinematic characteristics of the working components is crucial for ensuring the quality performance of machines used in the cutting of semi-finished macaroni products. These characteristics define the primary operational properties of the working components, such as cutting ability, stability, and durability, and their appropriate selection ensures the technological reliability of cutting machines. The research presented in this article aims to investigate the dependence of a knife's cutting ability on a set of factors, including the type and conditions of the cutting process, the geometry of the knives, and the cutting force. The study involves an analytical examination of the cutting ability of knives during three main periods: running-in, steady-state, and blunting. Additionally, a block diagram is developed to optimize the parameters of the knife's microgeometry. The research methods employed include analytical investigations using engineering calculations.
Impact of microgeometric parameters on the sliding cutting behavior of macaroni products
Authors: Urinov Nasillo F. , Saidova Mukhabbat Kh.
Published: May 2024

The primary objectives of the food industry sectors in the Republic of Uzbekistan are to intensify and optimize technological processes, adopt new progressive equipment for efficient processing modes, reduce energy costs and raw material losses, and improve product quality. Accordingly, this article presents a solution to one of the problems and provides an analysis of the cutting ability of the tool based on the investigated set of blade microgeometry parameters. The research aims to determine the numerical values of the microgeometry parameters for lamellar knife blades, obtained through various formation methods, and to identify the nature of their changes during operation. Additionally, the study explores the possibility of achieving such blade microgeometry parameters during sharpening, which were obtained through the optimization of the cutting ability objective function. The system described in the article has been implemented using the method of microscopic examination of lamellar knives, which allows for the photography of the blade surface and facets, contributing to the visual control of the cutting-edge condition immediately after its formation and during operation.
Integration of a hydrogen fuel cell into an electric vehicle for mainline cargo transportation
Authors: Nesterenko Grigory , Nesterenko Irina , Karnaukhov Andrey , Voinash Sergey , Abdullazyanov Edward , Sabitov Linar
Published: May 2024

The paper considers the issue of providing electric power to electric traction tractors. The importance of using electric vehicles from the point of view of the environmental situation is described. The use of electric motors for mainline cargo transportation is justified. In this regard, improving the performance of cargo transportation systems is always an urgent task. Increasing the indicators of efficiency, environmental riendliness, reliability and ergonomics within the framework of traditional power plants used today seems unpromising. In this regard, the application of fundamentally new technical solutions in road freight transport is more relevant. The article provides the rationale for choosing a tractor prototype. Such a car is the KAMAZ-54901. It describes how the layout of the placement of the main units and assemblies in the design of an electric vehicle will be changed. The main difference between the proposed design and classic electric vehicles is the possibility of using hydrogen elements to provide electric energy to the engines. The principle of operation of a hydrogen fuel cell is described.
Methods and technical means of reducing power losses in 0.38 kV networks with a symmetering device
Authors: Turduev Ilyaz , Kochkonbaeva Buazhar , Abdyraeva Nuripa
Published: May 2024

The relevance of this paper is due to the need to solve a specific problem, which is the reduction of power losses in asymmetrical electric receivers. The purpose of this paper is to develop methodological prerequisites for analyzing ways to reduce power losses caused by asymmetry of currents in a 0.38 kV network and to study the influence of current asymmetry on the increase of electrical losses, as well as to determine the effectiveness of symmetrical devices in reducing these losses. Among the methods used, we should mention the analytical method, classification method, functional method, statistical method, synthesis method and others. This paper highlights the issue of developing a methodology and theoretical studies, as well as conducting experimental studies on additional power losses caused by asymmetry of currents and voltages in 0.38 kV networks using symmetrical devices. The solution of problems of power supply and improvement of electric power quality in such low-voltage networks is closely connected with the problem of current asymmetry reduction. This study is of practical importance as it contributes new scientific knowledge and offers practical recommendations for effective improvement of low-voltage power networks.
Friction in roller technological machines
Authors: Khurramov Shavkat , Sattorova Shodiyona , Xalmamatova Lola , Chorshanbiev Zafar
Published: May 2024

The study is devoted to solving the problem of determining the patterns of friction stress distribution in the symmetric roll module contact zone. A mathematical model was developed that describes the patterns of friction stress distribution in the contact zone of roll modules. It was established that the ratio of friction stress to normal stress in the contact zone of roll modules is not constant and changes at each point of the contact zone. It was revealed that the ratio of friction stress to normal stress depends on external forces acting on the roll supports, geometric and kinematic parameters of the roll module, and deformation properties of the strip and roller coating.
Optimization of hydraulic drive parameters of caterpillar forest loader
Authors: Karnaukhov Ilia V. , Babin Vladimir V. , Ivanov Alexey Yu. , Romanenko Maxim Yu. , Serebrennikov Yuri E.
Published: May 2024

The document discusses the methodology for calculating the optimal parameters of a tracked forest loader. Based on the data obtained, a mathematical model of the kinematics of machine drives was compiled when the cargo was released "through itself." As a result of the work, changes in the demand for force on the boom lifting hydraulic cylinder and graphs of the dependence of the forces of the hydraulic cylinders on the angles of rotation of the boom and rocker were built. Based on the results of the work, conclusions were made about the change in the moments changed by the cargo.
Prospects for the lithium deposits development in Ukraine
Authors: Lozhnikov Oleksii , Pavlychenko Artem , Shustov Oleksandr , Dereviahina Nataliia
Published: May 2024

The article is devoted to establishing the current state of lithium deposits exploration in Ukraine and the prospects for providing strategic sectors of the economy with this critical raw material. The countries with the most favourable conditions for the lithium extraction from ore and sediment deposits, as well as the potential of Ukraine on the world market, were determined. Global trends in lithium consumption in various industries, as well as its impact on market value, have been established. The main directions of lithium use of in high-tech sectors of the economy and forecast indicators of the level of consumption until 2035 are given, which confirms the critical role of this material in the construction of electric vehicles, renewable energy and the defence industry. The mining and geological conditions for the occurrence of lithium deposits have been established, which indicates the possibility of mining this material by underground and surface method. The geological characteristics of the largest Ukrainian lithium deposits have been studied, which allows determining further directions for its development. Estimated reserves of lithium have been established in the most significant deposits of Ukraine, which include Polokhivske, Shevchenkivske, Dobra and Kruta Balka. The approximate content of lithium in the ore of the specified deposits has been determined, which makes it possible to forecast the country’s resource availability with this critical raw material and the strengthening of global technological chains in the future.
Numerical modelling of flow and heat transport in closed mines. Case study Walsum drainage province in the Ruhr coal-mining area
Authors: Rudakov Dmytro , Inkin Oleksandr , Wohnlich Stefan , Schiffer Rolf
Published: May 2024

High geothermal potential and multiple mine-water-based geothermal installations in Germany and other countries improve the relevance of detailed studies and modeling of promising sites. In this context, we developed a numerical model of water flow and heat transport in the Walsum mine drainage province in the west of the Ruhr coalmining area using the available data on geology, mining, water levels, pumping, and the temperatures of deep rocks and mine water. The model was validated by varying the parameters of groundwater recharge and hydraulic conductivity to achieve sufficient consistency with measured inflows and pumping rates from the central pumping facility located in the Walsum 2 shaft. The calculated mine water temperature of 30.3 ºC is close to the average of the measured temperature varied within the range of 29 – 33 ºC during the last years of mine maintenance. Using the numerical model, we evaluated the expected thermal capacity of a hypothetical open-loop circulation system and two closed-loop geothermal systems within the study area. The installation and operation of these systems would enable the generation of a thermal capacity from a few dozen kW to 1 MW sufficient for small-size to mid-size heat consumers with insignificant impact on the high thermal energy potential of the Walsum mine drainage province.
Natural phytomelioration of the coastal water zone of man-made reservoirs in mining areas
Authors: Tyndyk Oleh , Popovych Vasyl , Sai Kateryna , Petlovanyi Mykhailo
Published: May 2024

Coal mine waste heaps are technogenic hazards that have been polluting the air, surface and groundwater, soil for years. At the UN Climate Conference COP26, held in November 2021 in Glasgow (Scotland), Ukraine and developed countries committed to carbon neutrality by 2060 and to abandoning fossil fuels by 2035. One of the largest technogenic factors in waste heaps is subterranean wastewater. Wastewater accumulates in the man-made reservoirs at the foot of the coal mine waste heaps. In our case, one of the most effective means of improving coal mining regions’ environmental quality is phytomelioration, particularly coastal and water reclamation. The article presents the results of research within the Lviv-Volyn coal basin (Ukraine). During the study of natural phytomelioration processes in the coastal zone of man-made reservoirs, it was found that vegetation develops within four zones: I – underwater vegetation that is permanently covered by water (22% of the total number of species); II – vegetation of fluctuating water levels (32%); III – vegetation of the coastal zone (14%); IV – vegetation above the coastal zone (32%). The species composition includes 37 species belonging to 20 families. By family composition, the largest share of the species composition belongs to representatives of Asteraceae (15%), Poaceae (11%), Potamogetonaceae (8%). The study of the species composition and family spectrum of coastal and aquatic phytomelioration processes is important in implementing environmental protection and ecological measures to improve the quality of the environment of technogenically affected coal mining areas.
Improvement of the transitional technology from open pit to underground mining of magnetite quartzite
Authors: Stupnik Mykola , Kalinichenkо Vsevolod , Kalinichenko Olena , Shepel Oleksandr , Pochtarev Alexey
Published: May 2024

The paper analyzes the disadvantages of the technology of iron ore open pit mining and current environmental problems of open pit mining. The paper also addresses problems of possible displacement and strains of rocks in the classical open pit mining method with extraction of minerals exclusively by open pit mining, studies current transitional technologies from open pit to integrated open pit-underground and subsequent underground mining, and presents an improved methodology for studying the stress-strain state of the massif during transition from open pit mining to integrated open pit-underground and subsequent underground mining. There are studied, developed and proposed options of environmentally friendly technologies of integrated open pit-underground mining with mining waste disposal in the worked-out space of underground mines and open pits, highly efficient calculation schemes for studying the stress-strain state of a rock massif during transition from open pit to underground mining with formation of protective barrier pillars, an option with the development of the lower room of stage II under protection of an ore pillar left within the contours of the upper room of stage I, and an option with the development of the lower room of stage II under protection of an artificial pillar made of the consolidating backfill in the upper room of stage I. The stress-strain state of the massif and possibilities of forming internal waste rock dumps when applying integrated open pit-underground mining technologies are studied and substantiated. Transition technologies from open pit to underground mining of iron ore raw materials under the bottom of an operating open pit are developed and proposed on the example of Kryvyi Rih iron ore basin.
Ischemic Hepatitis and Septic Shock Secondary to Murine Typhus Infection in Pregnancy
Authors: Berry Marissa , Wang Amanda M. , Lahham Rana F. , Zhang Xue , Pacheco Luis D.
Published: May 2024

Infection with murine typhus may be associated with significant morbidity. With nonspecific symptoms and laboratory abnormalities, diagnosis may be challenging. In this case, a pregnant patient presented with complaints of fevers and myalgias. Her laboratory results included severe transaminitis as well as thrombocytopenia and hyponatremia. She ultimately required vasopressor support and intensive care unit admission despite fluid resuscitation and broad-spectrum antibiotics. Empiric doxycycline was initiated due to suspicion for murine typhus, which laboratory testing later confirmed. Her clinical status improved with these interventions. This was a severe case of murine typhus resulting in septic shock and ischemic hepatitis. It is important to know the typical findings of murine typhus and consider it in a differential diagnosis, especially when practicing in endemic areas.
Research on temporal diversity in GVTs: limitations and a new research agenda
Authors: Taras Vas , Stahl Günter K. , Gunkel Marjaana , Kraemer Justin
Published: May 2024

In addition to cultural and demographic diversity, temporal diversity is increasingly recognized as a crucial factor affecting the dynamics and performance of global virtual teams (GVTs). However, research on temporal diversity tends to analyze the effects of only one source of timing differences at a time: either only time-zone differences or only chronotype differences among the team members. Such a single-focus approach is limiting, and could lead to biased conclusions. We provide a conceptual model that shows how analyzing only one source of temporal diversity at a time can produce an incomplete and even misleading picture. Based on the analysis of different temporal activation patternings, namely the arrangements of timing when team members can fully engage in project-related tasks, we demonstrate how the interplay between time zones and chronotypes can exacerbate or mitigate temporal diversity, resulting in temporal patterns that could be more or less advantageous for a GVT, depending on the team characteristics and nature of its task. We discuss the implications of failing to simultaneously consider both sources of temporal differences when analyzing timing differences among GVT members and provide a guide for future research and practice for handling the issue of temporal diversity more effectively.
Rapid vertebrate speciation via isolation, bottlenecks, and drift
Authors: Black Andrew N. , Heenkenda Erangi J. , Mathur Samarth , Willoughby Janna R. , Pierce Brian L. , Turner Sarah J. , Rizzuto David , DeWoody J. Andrew
Published: May 2024

Speciation is often driven by selective processes like those associated with viability, mate choice, or local adaptation, and “speciation genes” have been identified in many eukaryotic lineages. In contrast, neutral processes are rarely considered as the primary drivers of speciation, especially over short evolutionary timeframes. Here, we describe a rapid vertebrate speciation event driven primarily by genetic drift. The White Sands pupfish (
Cyprinodon tularosa
) is endemic to New Mexico’s Tularosa Basin where the species is currently managed as two Evolutionarily significant units (ESUs) and is of international conservation concern (Endangered). Whole-genome resequencing data from each ESU showed remarkably high and uniform levels of differentiation across the entire genome (global F
ST
≈ 0.40). Despite inhabiting ecologically dissimilar springs and streams, our whole-genome analysis revealed no discrete islands of divergence indicative of strong selection, even when we focused on an array of candidate genes. Demographic modeling of the joint allele frequency spectrum indicates the two ESUs split only ~4 to 5 kya and that both ESUs have undergone major bottlenecks within the last 2.5 millennia. Our results indicate the genome-wide disparities between the two ESUs are not driven by divergent selection but by neutral drift due to small population sizes, geographic isolation, and repeated bottlenecks. While rapid speciation is often driven by natural or sexual selection, here we show that isolation and drift have led to speciation within a few thousand generations. We discuss these evolutionary insights in light of the conservation management challenges they pose.
Physical immune escape: Weakened mechanical communication leads to escape of metastatic colorectal carcinoma cells from macrophages
Authors: Yang Chen , Dong Xinrui , Sun Bingrui , Cao Ting , Xie Ruipei , Zhang Yiyu , Yang Ziyue , Huang Jing , Lu Ying , Li Ming , Wang Xiaochen , Xu Ye , Ye Fangfu , Fan Qihui
Published: May 2024

The significance of biochemical cues in the tumor immune microenvironment in affecting cancer metastasis is well established, but the role of physical factors in the microenvironment remains largely unexplored. In this article, we investigated how the mechanical interaction between cancer cells and immune cells, mediated by extracellular matrix (ECM), influences immune escape of cancer cells. We focus on the mechanical regulation of macrophages’ targeting ability on two distinct types of colorectal carcinoma (CRC) cells with different metastatic potentials. Our results show that macrophages can effectively target CRC cells with low metastatic potential, due to the strong contraction exhibited by the cancer cells on the ECM, and that cancer cells with high metastatic potential demonstrated weakened contractions on the ECM and can thus evade macrophage attack to achieve immune escape. Our findings regarding the intricate mechanical interactions between immune cells and cancer cells can serve as a crucial reference for further exploration of cancer immunotherapy strategies.
Accelerating diabetic wound healing by ROS-scavenging lipid nanoparticle–mRNA formulation
Authors: Wang Siyu , Zhang Yuebao , Zhong Yichen , Xue Yonger , Liu Zhengwei , Wang Chang , Kang Diana D. , Li Haoyuan , Hou Xucheng , Tian Meng , Cao Dinglingge , Wang Leiming , Guo Kaiyuan , Deng Binbin , McComb David W. , Merad Miriam , Brown Brian D. , Dong Yizhou
Published: May 2024

Current treatment options for diabetic wounds face challenges due to low efficacy, as well as potential side effects and the necessity for repetitive treatments. To address these issues, we report a formulation utilizing trisulfide-derived lipid nanoparticle (TS LNP)-mRNA therapy to accelerate diabetic wound healing by repairing and reprogramming the microenvironment of the wounds. A library of reactive oxygen species (ROS)-responsive TS LNPs was designed and developed to encapsulate interleukin-4 (IL4) mRNA. TS2-IL4 LNP-mRNA effectively scavenges excess ROS at the wound site and induces the expression of IL4 in macrophages, promoting the polarization from the proinflammatory M1 to the anti-inflammatory M2 phenotype at the wound site. In a diabetic wound model of db/db mice, treatment with this formulation significantly accelerates wound healing by enhancing the formation of an intact epidermis, angiogenesis, and myofibroblasts. Overall, this TS LNP-mRNA platform not only provides a safe, effective, and convenient therapeutic strategy for diabetic wound healing but also holds great potential for clinical translation in both acute and chronic wound care.
Acoustic and articulatory variation of Mandarin diphthong /ou/
Authors: Chang Yung-hsiang Shawn
Published: May 2024

This study compared dynamic formant trajectories and corresponding ultrasound tongue data of the diphthong /ou/ in Taiwan Mandarin and Beijing Mandarin speakers. Results of the Generalized Additive Mixed Models (GAMM) analyses showed that both groups of speakers produced a clearly diphthongal /ou/, which contrasts with previous auditory-based accounts that /ou/ in Taiwan Mandarin may be monophthongal. The two dialects, however, had rather different phonetic realizations: Taiwan Mandarin had a significantly lower realization for the nucleus of /ou/ than its Beijing counterpart; Taiwan Mandarin also had a significantly more fronted realization for the offglide than Beijing Mandarin. The articulatory patterns mostly corresponded to the acoustic results, in that while tongue dorsum raising was found for all speakers in this study, an additional tongue dorsum fronting gesture was observed for the majority of the Taiwan Mandarin speakers. Together, the results suggest that the less studied dialectal variation in Mandarin vowels may be a promising line of investigation, particularly with parallel acoustic and articulatory data collection.
Gorani substrate within Kurdish
Authors: Mohammadirad Masoud
Published: May 2024

The traditional view within Kurdish linguistics is that the split between Central Kurdish (CK) and Northern
Kurdish (NK) is mainly the result of a Gorani substrate within the former group. More recent studies refute this hypothesis,
arguing instead that Kurdish was initially composed of two distinct but closely related subgroups and that the differences between
CK and NK are partly due to distinct source languages and partly due to ensuing contact with neighbouring languages. This study
aims to shed new light on the Gorani-substrate hypothesis within CK by examining a corpus-based study of the southernmost CK
dialects located within the historical Gorani heartland. Combining recent historical accounts of language shift from Gorani to CK
in the region with linguistic data, the paper claims that (i) Gorani borrowings and substrate features reflect different layers of
historical contact in Southern CK dialects and (ii) the Gorani substrate has caused a split in the morphosyntactic features across
vernaculars of CK, showcasing second-language learning in shaping the historically recent development of Southern CK dialects.
Hydrophobic residues in S1 modulate enzymatic function and voltage sensing in voltage-sensing phosphatase
Authors: Rayaprolu Vamseedhar , Miettinen Heini M. , Baker William D. , Young Victoria C. , Fisher Matthew , Mueller Gwendolyn , Rankin William O. , Kelley John T. , Ratzan William J. , Leong Lee Min , Davisson Joshua A. , Baker Bradley J. , Kohout Susy C.
Published: May 2024

The voltage-sensing domain (VSD) is a four-helix modular protein domain that converts electrical signals into conformational changes, leading to open pores and active enzymes. In most voltage-sensing proteins, the VSDs do not interact with one another, and the S1–S3 helices are considered mainly scaffolding, except in the voltage-sensing phosphatase (VSP) and the proton channel (Hv). To investigate its contribution to VSP function, we mutated four hydrophobic amino acids in S1 to alanine (F127, I131, I134, and L137), individually or in combination. Most of these mutations shifted the voltage dependence of activity to higher voltages; however, not all substrate reactions were the same. The kinetics of enzymatic activity were also altered, with some mutations significantly slowing down dephosphorylation. The voltage dependence of VSD motions was consistently shifted to lower voltages and indicated a second voltage-dependent motion. Additionally, none of the mutations broke the VSP dimer, indicating that the S1 impact could stem from intra- and/or intersubunit interactions. Lastly, when the same mutations were introduced into a genetically encoded voltage indicator, they dramatically altered the optical readings, making some of the kinetics faster and shifting the voltage dependence. These results indicate that the S1 helix in VSP plays a critical role in tuning the enzyme’s conformational response to membrane potential transients and influencing the function of the VSD.
Frequency selective rasorber based on cross bend resonators for wideband transmission and absorption
Authors: Li Xiu-Feng , Wang Chao , Wang Bing , Du JunZhao , Zhang Sheng-Jun , Wang Ru-Zhi
Published: May 2024

The wideband absorption and transmission of frequency-selective rasorber (FSR) remain a persistent challenge in the application of radar devices. In this article, a novel high performance wideband FSR design based on cross bend resonators was proposed. The FSR consists of an upper absorption lossy layer, which offers broad absorption and transmission bands, and a lower bandpass frequency-selective surface that enables a highly selective transmission of incident electromagnetic wave. Full wave simulation results showed that this novel design achieves an absorption bandwidth of 83.7% with more than 90% absorptivity in the frequency range of 5.2–12.7 GHz. Furthermore, the passband’s fractional bandwidth for the insertion loss (IL) less than −3 dB is 33.9%, ranging from 14.9 to 21 GHz, with the minimum IL recorded at 0.69 dB at 17.7 GHz. To further verify the proposed method, a prototype FSR with 10 × 10 units of 120 mm × 120 mm was fabricated and the performance of the FSR was tested. The experiment results were in good agreement with the simulated results, and it showed a significant monostatic radar cross-section reduction in the frequency range of 5.3 GHz to 18.3 GHz compared with a metallic plane of the same size.
A cross species thermoelectric and spatiotemporal analysis of alternans in live explanted hearts using dual voltage-calcium fluorescence optical mapping
Authors: Crispino Anna , Loppini Alessandro , Uzelac Ilija , Iravanian Shahriar , Bhatia Neal K , Burke Michael , Filippi Simonetta , Fenton Flavio H , Gizzi Alessio
Published: May 2024

Objective. Temperature plays a crucial role in influencing the spatiotemporal dynamics of the heart. Electrical instabilities due to specific thermal conditions typically lead to early period-doubling bifurcations and beat-to-beat alternans. These pro-arrhythmic phenomena manifest in voltage and calcium traces, resulting in compromised contractile behaviors. In such intricate scenario, dual optical mapping technique was used to uncover unexplored multi-scale and nonlinear couplings, essential for early detection and understanding of cardiac arrhythmia. Approach. We propose a methodological analysis of synchronized voltage-calcium signals for detecting alternans, restitution curves, and spatiotemporal alternans patterns under different thermal conditions, based on integral features calculation. To validate our approach, we conducted a cross-species investigation involving rabbit and guinea pig epicardial ventricular surfaces and human endocardial tissue under pacing-down protocols. Main results. We show that the proposed integral feature, as the area under the curve, could be an easily applicable indicator that may enhance the predictability of the onset and progression of cardiac alternans. Insights into spatiotemporal correlation analysis of characteristic spatial lengths across different heart species were further provided. Significance. Exploring cross-species thermoelectric features contributes to understanding temperature-dependent proarrhythmic regimes and their implications on coupled spatiotemporal voltage-calcium dynamics. The findings provide preliminary insights and potential strategies for enhancing arrhythmia detection and treatment.
Highly comparative time series analysis of oxygen saturation and heart rate to predict respiratory outcomes in extremely preterm infants
Authors: Qiu Jiaxing , Di Fiore Juliann M , Krishnamurthi Narayanan , Indic Premananda , Carroll John L , Claure Nelson , Kemp James S , Dennery Phyllis A , Ambalavanan Namasivayam , Weese-Mayer Debra E , Maria Hibbs Anna , Martin Richard J , Bancalari Eduardo , Hamvas Aaron , Randall Moorman J , Lake Douglas E ,   Pre-Vent Investigators, Krahn Katy N , Zimmet Amanda M , Hopkins Bradley S , Lonergan Erin K , Rand Casey M , Zadell Arlene , Nakhmani Arie , Carlo Waldemar A , Laney Deborah , Travers Colm P , Vanbuskirk Silvia , D’Ugard Carmen , Aguilar Ana Cecilia , Schott Alini , Hoffmann Julie , Linneman Laura
Published: May 2024

Objective. Highly comparative time series analysis (HCTSA) is a novel approach involving massive feature extraction using publicly available code from many disciplines. The Prematurity-Related Ventilatory Control (Pre-Vent) observational multicenter prospective study collected bedside monitor data from

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700

extremely preterm infants to identify physiologic features that predict respiratory outcomes. Approach. We calculated a subset of 33 HCTSA features on

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7

 M 10 min windows of oxygen saturation (SPO2) and heart rate (HR) from the Pre-Vent cohort to quantify predictive performance. This subset included representatives previously identified using unsupervised clustering on

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3500

HCTSA algorithms. We hypothesized that the best HCTSA algorithms would compare favorably to optimal PreVent physiologic predictor IH90_DPE (duration per event of intermittent hypoxemia events below 90%). Main Results. The top HCTSA features were from a cluster of algorithms associated with the autocorrelation of SPO2 time series and identified low frequency patterns of desaturation as high risk. These features had comparable performance to and were highly correlated with IH90_DPE but perhaps measure the physiologic status of an infant in a more robust way that warrants further investigation. The top HR HCTSA features were symbolic transformation measures that had previously been identified as strong predictors of neonatal mortality. HR metrics were only important predictors at early days of life which was likely due to the larger proportion of infants whose outcome was death by any cause. A simple HCTSA model using 3 top features outperformed IH90_DPE at day of life 7 (.778 versus .729) but was essentially equivalent at day of life 28 (.849 versus .850). Significance. These results validated the utility of a representative HCTSA approach but also provides additional evidence supporting IH90_DPE as an optimal predictor of respiratory outcomes.