bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Step-Wise Method for Measuring Thermophysical Parameters of an Isotropic Material, Considering the Effect of Thermal Contact Resistance and Lateral Convection Losses
Authors: Dia Mohameth , Diallo Mamadou Salif , Faye Mactar , Sambou Vincent 
Published: September 2024

Abstract
This work proposes a model based on the step-wise method to identify conductivity and heat capacity. Contrary to conventional models, this model considers the thermal properties of the heating element, the thermal contact resistance at the measurement point, and the lateral convection losses around the device. The mathematical model is solved using a numerical approach based on the finite element method (FEM) to obtain the temperature distribution over the entire measurement device. This temperature field is generated by the passage of electric current through a flat electrical resistor made of thin metal foil (Kapton). Heat is produced as a progressive function. A thermocouple placed at a distance from the heat source measures the temperature response. A sensitivity analysis showed that the heating element parameters did not affect the long-term estimates. Additionally, this sensitivity analysis showed the possibility of estimating conductivity, heat capacity, contact resistance, and convection coefficient. Experimental data obtained with this model on two materials are compared with results obtained using conventional methods (HotDisk TPS2200, fluxmeter). There is a 2.5% difference between the thermal conductivities obtained with our model and the HotDisk and fluxmeter methods. The maximum relative error in thermal capacity is 6%.
A Wide-Bandwidth and High-Resolution Identification Method for the Dynamic Characteristics of Annular Gas Seals Using Hilbert Transform
Authors: Wang Tianhao , Li Zhigang , Li Jun 
Published: September 2024

Abstract
Efficient and accurate parameter identification methods are urgently needed to develop high-performance sealing devices. Although the existing prediction methods have been widely validated, researchers are still grappling with the tradeoff between frequency resolution and computational cost. This paper proposed a Hilbert-transform-based time-frequency analysis method to identify the dynamic characteristics of annular gas seals. The frequency-sweep whirling orbit model (FSM) was adopted as the excitation signal of rotor whirling motion. The transient flow field within the seal clearance was numerically simulated by the computational fluid dynamic (CFD) solution combined with the mesh deformation technique. The empirical amplitude-modulated (AM) and frequency-modulated (FM) decomposition and the direct quadrature method were utilized to approximate the analytic signals of monitored response forces. High-resolution and frequency-dependent dynamic coefficients were determined by the Hilbert transform (HT) of the linear response-force/rotor-motion model. To validate the present method and determine the frequency-sweep mode, the dynamic coefficients of three typical annular gas seals, including a labyrinth seal (LABY), a fully partitioned pocket damper seal (FPDS), and a hole-pattern seal (HPS), were evaluated by the linear and quadratic frequency-sweep modes, respectively. The results indicate that the dynamic coefficients obtained by the quadratic FSM are all in good agreement with the experimental data, and have almost the same accuracy as the well-known multifrequency whirling orbit model (MFM). Combined with the proposed adaptive time-step scheme, the present method can obtain high-frequency-resolution dynamic coefficients of annular gas seals with a 48.6% reduction in computational time compared to MFM. Furthermore, the application of the present method in wide-bandwidth cases was also illustrated.
Fabrication Time Diagrams for In-Space Manufacturing of Large Reticulated Structures
Authors: Bhundiya Harsh G. , Marshall Michael A. , Cordero Zachary C. 
Published: September 2024

Abstract
In-space manufacturing (ISM), or the construction of structures from raw feedstock materials in the space environment, is a promising approach for building large, external support structures for future space missions. Most research and development on ISM to date has focused on ground-based or microgravity-based demonstrations of candidate fabrication processes; however, the combined design of the ISM spacecraft and the fabrication process has not been fully investigated. In this paper, we estimate the fabrication times for truss support structures subject to various spacecraft constraints, including the available fabrication power, the attitude control system (ACS) authority, and the avoidance of control–structure interactions. Using the key assumptions of (1) a fabrication process that sequentially extrudes struts, (2) a fixed spacecraft orientation, and (3) negligible effects of environmental disturbance torques, we generate fabrication time diagrams that depict the dominant constraints and estimates of the fabrication time for a range of dimensions. Our results indicate that for large, dense reticulated geometries such as the curved gridshell and tetrahedral truss, the angular momentum storage of the spacecraft ACS is the dominant constraint on fabrication time. Additionally, our results suggest the following strategies for reducing fabrication time: manufacturing with multiple spacecraft; using stiff, lightweight feedstock; maximizing fabrication power and ACS capability; and minimizing spacecraft bus mass. These strategies represent design tradeoffs, emphasizing how the design of an ISM spacecraft cannot be considered independently of the fabricated structure.
Ultrasound-Enabled Adaptive Protocol for Fast Charging of Lithium-Ion Batteries
Authors: Im Ganghyeok , Lu Wei , Popa Bogdan Ioan , Epureanu Bogdan I. 
Published: September 2024

Abstract
This paper introduces an ultrasound-assisted multistage constant current (UA-MSCC) charging protocol to enhance the charging performance of lithium-ion batteries. In this approach, ultrasound is applied during the final portion of each MSCC charging phase. Experimental results demonstrate that ultrasound decreases the internal resistance of pouch cells by up to 7%, leading to significant increase in charging capacity during each MSCC stage. The overall charging time is reduced by 26% compared to the conventional constant current–constant voltage (CCCV) protocol. The performance improvement delivered by this ultrasound-assisted charging approach is especially large when the battery is charged at low temperatures and to a partial capacity. Notably, the application of ultrasound improves the coulombic efficiency to levels comparable to that at the room temperature when charging in cold environments (0 °C). This approach can be applied to commercial batteries to immediately improve their charging performance, and can be seamlessly integrated into battery management systems. Unlike approaches that necessitate electrode material modifications or electrolyte additives, which require a long development time, this UA-MSCC charging protocol offers a practical and easily applicable solution for improving the battery charging performance.
Heat Transfer Performance Analysis of Medium–Deep Coaxial Borehole Heat Exchanger: Combination of Heat Extraction Operation Test and Numerical Simulation
Authors: Li Jiangbo , Lei Yanzi , Li Lei , Chen Sihao 
Published: September 2024

Abstract
Geothermal energy is a clean and renewable energy source that can effectively reduce carbon emissions. Coaxial borehole heat exchanger (CBHE) is a crucial component of the geothermal mining system. To understand the heat transfer mechanism of a CBHE and to design its construction, this paper analyzes the geotechnical thermal response characteristics of CBHE under constant power conditions. comsol was used to simulate the performance of the heat exchanger during intermittent operation in both summer and winter. The results indicate that the inlet water temperature and the thermal conductivity of the grouting material have a weak impact on the energy efficiency coefficient of the heat exchanger. The energy efficiency coefficient can increase by about 22% when the inner pipe's thermal conductivity is low. The temperature difference between the medium flowing into the inner pipe at the bottom of a shallow-cased buried pipe and the medium flowing out of the inner pipe defines the thermal short-circuit value. The influence on the thermal short-circuit value is on the order of the inner pipe thermal conductivity, grouting material thermal conductivity, and the inlet water temperature. The fluctuation of soil temperature in the summer is greater than that in the winter, and the soil temperature of shallow-buried pipes is easier to recover in the winter. The characteristic law obtained in this paper provides a valuable reference for the scientific design of CBHE.
Research on Thermal Comfort of Human Body Under Localized Automotive Air Conditioning
Authors: Wang Jingyu , Xie Xinran , Hu Xingjun , Wang Binbin , Guo Peng , Yu Tianming 
Published: September 2024

Abstract
In this study, we design localized automotive air conditioning to balance the contradiction between the thermal comfort of the driver in the cockpit and the energy-saving and environmental protection of an automobile's air conditioner. The simplified model of a certain car cockpit is selected as the research object. Three types of air outlet structures of localized automotive air conditioning are designed, and numerical simulation is performed to study flow field distribution and human thermal comfort in the cockpit under different air outlet combinations of localized automotive air conditioning. The final evaluation result indicates that the thermal comfort of the driver is good under localized automotive air conditioning. Moreover, the energy-saving effect of localized automotive air conditioning is remarkable and its cooling rate is faster. Localized automotive air conditioning achieves about 41.4% more energy saving than ordinary automotive air conditioning.
Parallel Force Feedback Device Design With Constant Jacobian Matrix and Net Weight Fully Balanced
Authors: Jin Zhaopeng , Zhao Yanzhi , Liu Yajun , Shan Yu , Sun Yue 
Published: September 2024

Abstract
Force feedback devices offer realistic and intuitive feedback to operators, and achieving higher accuracy and transparency has been a prominent research focus in this field. However, errors in real-time force or position calculations are inevitable, which can have adverse effects on the accuracy of the equipment. This article presents the design of a parallel mechanism that incorporates a constant force and velocity mapping relationship based on the type synthesis of the constant Jacobian matrix. Specifically, the mechanism maintains a fixed direction of force applied to the operating platform by the drive pair, which is mounted on the fixed platform in each limb, irrespective of position changes. This unique feature enables the mechanism to achieve a complete net weight balance. The implementation method is detailed in this article, which involves adding appropriate counterweights to achieve a balance between the weight of the connecting rod and the overall gravity of the operating platform. Furthermore, the optimization of structural parameters helps to improve the performance of the developed prototype. The proposed design scheme not only addresses the fundamental reduction of errors caused by real-time force and position mapping solving but also enhances operational transparency. Finally, simulation and experimental tests are conducted to validate the proposed theory.
A very versatile molecular machine
Authors: Manson Michael D. 
Published: September 2024

ABSTRACT

In this issue (J Bacteriol. 206: e0014024,
https://doi.org/10.1128/jb.00140-24
), Ridone and Baker describe hybrids between two 5:2 heteroheptameric ion-powered motors. Chimeras were constructed between stator units of a bacterial flagellum and ExbBD of the Ton outer-membrane transport system. Only one of the 14 hybrids supported swimming in
Escherichia coli
. Three additional residue changes at sites distant from the hybrid region enhanced motility. This work suggests that flagellar stator units and ExbBD share an ancestor that diverged during evolution to perform different tasks.
Development of inducible promoter and CRISPRi plasmids functional in
Rickettsia rickettsii
Authors: Nock Adam M. , Clark Tina R. , Hackstadt Ted 
Published: September 2024

ABSTRACT

Rickettsia rickettsii
is an obligate intracellular, tick-borne bacterium that causes Rocky Mountain spotted fever. The demanding nature of cultivating these bacteria within host cells and the labor involved in obtaining clonal isolates have severely limited progress regarding the development of compatible genetic tools to study this pathogen. Conditional expression of genes that might be toxic or have an otherwise undesirable effect is the next logical goal to expand upon the constitutive expression plasmids generated thus far. We describe the construction of an inducible promoter system based on the tet-On system, leveraging design elements from the anhydrotetracycline-inducible promoter system used for
Borrelia burgdorferi
and one of the few characterized rickettsial promoters for the outer membrane gene,
rompB
(
sca5
). The functionality of this promoter is demonstrated via fluorescence of induced mScarlet production and was then used to construct a generalized inducible expression vector for
R. rickettsii
. The development of a functional inducible promoter was then applied to the construction of a CRISPR interference plasmid as a means to reduce or essentially silence the transcription of targeted genes. We demonstrate the viability of a simplified, single vector CRISPRi system to disrupt gene expression in
R. rickettsii
targeting the type IV secreted effector
rarP2
and autotransporter peptidase
rapL
as examples.

IMPORTANCE

This work expands upon the genetic toolbox available for
R. rickettsii
. We describe both an inducible promoter and CRISPRi system compatible with
Rickettsia
, which may provide key instruments for the development of further tools. The development of an inducible promoter system allows for the overexpression of genes, which might be toxic when expressed constitutively. The CRISPRi system enables the ability to knock down genes with specificity, and critically, genes that may be essential and could not otherwise be knocked out. These developments may provide the foundation for unlocking genetic tools for other pathogens of the order Rickettsiales, such as the
Anaplasma
,
Orientia
, and
Ehrlichia
for which there are currently no inducible promoters or CRISPRi platforms.
Anaerobic Oxidation of Oil by Microbial Communities of Bottom Sediments of a Natural Oil Seepage Site (Bolshaya Zelenovskaya, Middle Baikal)
Authors: Pavlova O. N. , Bukin S. V. , Izosimova O. N. , Chernitsina S. M. , Ivanov V. G. , Khabuev A. V. , Pogodaeva T. V. , Elovskaya I. S. , Gorshkov A. G. , Zemskaya T. I. 
Published: September 2024

Abstract
The microbial communities of bottom sediments of the Bolshaya Zelenovskaya oil seepage site (Lake Baikal) were investigated to assess their diversity and potential functional activity in the anaerobic degradation of oil. Microorganisms of the subsurface and deep sediment layers were grown in enrichment cultures supplemented with oil and various electron acceptors for 1 year at 10°C, and it was found that the concentrations of n-alkanes and polyaromatic hydrocarbons decreased by 1.2–2 and 2.2–2.8 times, respectively. Hydrocarbon conversion was accompanied by generation of hydrocarbon gases (methane and ethane). The microbial community of subsurface sediments had a higher bacterial diversity than the community of deep horizons and was composed of microorganisms specialized in degradation of a broad range of substrates, including oil hydrocarbons. The community of the deep sediment layer was dominated by Atribacterota, Caldisericota, and Bathyarchaeia (Thermoproteota), as well as members of the “rare biosphere”: Elusimicrobiota and Candidatus Hadarchaeota. Apparently, oil degradation in the bottom sediments of Lake Baikal is primarily mediated by members of the phyla Bacillota, Pseudomonadota, Chloroflexota, Actinomycetota, Desulfobacterota, Atribacterota, Halobacteriota, and Bathyarchaeia (Thermoproteota).
Comparative Genomics of Carbohydrate Utilization in Bacteria of the Family Sphaerochaetaceae: Evolutionary Origin of the Genes Encoding Galacturonidase and Unsaturated Rhamnogalacturonyl Hydrolase
Authors: Troshina O. Yu. , Naumoff D. G. , Rechkina V. I. , Shcherbakova V. A. 
Published: September 2024

Abstract
A comparative analysis of carbohydrate degradation proteins encoded in the currently available genomic sequences of bacteria of the family Sphaerochaetaceae, namely Sphaerochaeta associata GLS2T, S. globosa BuddyT, S. pleomorpha GrapesT, S. halotolerans 4-11T, S. halotolerans 585, Sphaerochaeta sp. S2, Sphaerochaeta sp. PS, and Parasphaerochaetacoccoides SPN1T was carried out. The genomes of Sphaerochaeta spp. encode a medium-sized and diverse set of proteins potentially involved in the degradation of different classes of carbohydrates, mainly oligosaccharides. All studied genomes encode glycoside hydrolases of the GH1, GH2, GH3, GH4, GH13, GH20, GH28, GH36, GH43, GH57, GH63, GH77 and GH105 families, as well as carbohydrate esterases of the CE8 and CE9 families. All studied bacteria, with the exception of P. coccoides SPN1T, have many genes of the GH31 family proteins. The studied members of Sphaerochaetaceae do not have genes coding for endo-β-acetylmuramidase (lysozyme) of the GH23 family, which participates in peptidoglycan turnover. However, the genomes of S. associata, S. globosa, Sphaerochaeta sp. PS, and S. pleomorpha contain exo-β-acetylmuramidase genes (GH171 family). A significant part of the genes encoding carbohydrate degradation enzymes have the closest homologues among representatives of the phyla Bacillota, Bacteroidota, and Pseudomonadota. The genomes of the studied bacteria encode proteins that could potentially be involved in the degradation of pectin. The ability of the Sphaerochaetaceae members to use pectin for growth, as well as the evolutionary origin of the genes encoding potential α-galacturonidase (GH4 family) and unsaturated glucuronyl/rhamnogalacturonyl hydrolase (GH105 family), which participate in the degradation of pectin components, were studied.
Speciation and formation constants of aqueous lanthanum (III) chloride complexes from 5 to 80 °C by Raman spectroscopy
Authors: Persaud Avinaash A. , Sasidharanpillai Swaroop , Cox Jenny S. , Tremaine Peter R. 
Published: September 2024

Lanthanum chloride solutions were studied both computationally and by polarized Raman spectroscopy to determine the aqueous species present and their equilibrium constants. Four species were predicted from Gaussian 16 computations using density functional theory: La(H2O)9 3+, LaCl(H2O)8 2+, LaCl2(H2O)6 2+, and LaCl3(H2O)4 0. Both LaCl(H2O)8 2+ and LaCl2(H2O)6 + were identified in the reduced isotropic solvent-subtracted Raman spectra from their La–Cl vibrational bands at 234 and 221 cm−1, respectively. The spectra did not change significantly with temperature from 5 to 80 °C, and the Raman bands for each species could not be fitted with sufficient accuracy to determine the scattering coefficients directly from the experimental data. Instead, the computed scattering coefficients from Gaussian 16 (B3LYP with the Los Alamos National Laboratory 2-double-zeta effective core potential and 6-311+G(d,p) basis set) were to be used to obtain the equilibrium concentrations of LaCl(H2O)8 2+ and LaCl2(H2O)6 +, from which the concentration of La(H2O)9 3+ was determined. The concentration dependent formation quotients were fitted with the specific ion interaction (SIT) activity coefficient model to determine the stepwise formation constants K0, 1 and K1, 2, from 5 to 80 °C. Both K0, 1 and K1, 2 showed minor increases with temperature.
Circular orbits of accretion flow around charged black hole coupled with a nonlinear electrodynamics field
Authors: Rehman H. , Abbas G. , Zhu Tao , Wu Qiang , Mustafa G. 
Published: September 2024

AbstractThis study investigates the particle’s geodesic motion and accretion around the spherically symmetric Reissner–Nordström black hole coupled with a nonlinear electrodynamics field. The formation of the disc-like structure in the accretion process arises from the geodesic motion exhibited by particles near the black hole. In the equatorial plane, we analyze the circular orbits of particles and their stability in detail. The analysis of the fluid’s critical flow, maximum accretion rate, radiant flux energy, radioactive efficiency, and radiant temperature are also examined near the central object. We analyze the perturbations experienced by particles throughout, employing restoring forces and the oscillatory behavior of the particles around the black hole. Our results show that the NED parameter $$\zeta $$
ζ
affects the circular geodesics of particles and the maximum accretion rate of the Reissner–Nordström black hole coupled with nonlinear electrodynamics.
Comparison of short-term breathing rate asymmetry of preeclamptic and normotensive women in labor
Authors: Gonzalez-Reyes Ximena , Mendieta-Zerón Hugo , Abarca-Castro Eric Alonso , Talavera-Peña Ana Karen , Santiago-Fuentes Laura Mercedes , Reyes-Lagos José Javier 
Published: September 2024

AbstractBreathing rate asymmetry (BRA) refers to the observed disparities in the acceleration and deceleration phases of human respiration. The techniques employed to assess BRA could also be utilized in exploring hypertensive disorders like pre-eclampsia, which is known to cause autonomic cardiorespiratory changes. This study explores features of complexity, including the asymmetry (time irreversibility) of short-term breath-to-breath breathing rate variability among women with severe and moderate pre-eclampsia features compared to those with normal blood pressure. In our study, we retrospectively analyzed continuous respirogram recordings from women in labor, including those diagnosed with severe pre-eclampsia (SP = 22), moderate pre-eclampsia (P = 19), and normotensive control group (C = 35). Using these data, we calculated 5 min of breath-to-breath (BB) time series to measure Porta's index (P%), Guzik's index (G%), and Ehlers' index (E), alongside measures of asymmetrical entropy, including the entropy of acceleration runs (HAR), the entropy of deceleration runs (HDR), and total entropy (H). In addition, Fuzzy Entropy (FuzzEn) and Multiscale Fuzzy Entropy (MFE) over timescales 1–20 were calculated from the BB time series. The nonlinearity was assessed by surrogate analysis. The study's results revealed significant differences in short-term BRA; specifically, mean values of G% and E were the lowest in SP compared to C and P. Conversely, mean values of the HDR were higher in the SP group than the C. Higher mean values of MFE and a greater percentage of nonlinearity were observed in the SP group as compared to the C group. Our results suggest that women with severe pre-eclampsia may exhibit a higher short-term BRA characterized by a lower contribution of breathing rate decelerations to short-term variability, higher irregularity and nonlinearity of BB time series, and particularly more irregular behavior of decelerations compared to normotensive women. This may indicate a potential modification in the autonomic control of breathing rate and breathing instability.