bluuebunny/crossref_metadata_2025 huggingface dataset:
Extending GPU-accelerated Gaussian integrals in the TeraChem software package to f type orbitals: Implementation and applications
Authors: Wang Yuanheng , Hait Diptarka , Johnson K. Grace , Fajen O. Jonathan , Zhang Juncheng Harry , Guerrero Rubén D. , Martínez Todd J.
Published: November 2024

The increasing availability of graphics processing units (GPUs) for scientific computing has prompted interest in accelerating quantum chemical calculations through their use. However, the complexity of integral kernels for high angular momentum basis functions often limits the utility of GPU implementations with large basis sets or for metal containing systems. In this work, we report the implementation of f function support in the GPU-accelerated TeraChem software package through the development of efficient kernels for the evaluation of Hamiltonian integrals. The high efficiency of the resulting code is demonstrated through density functional theory (DFT) calculations on increasingly large organic molecules and transition metal complexes, as well as coupled cluster singles and doubles calculations on water clusters. Preliminary investigations into Ni(I) catalysis with DFT and the photochemistry of MnH(CH3) with complete active space self-consistent field are also carried out. Overall, our GPU-accelerated software appears to be well-suited for fast simulation of large transition metal containing systems, as well as organic molecules.
Self-correction of the optical distortion effect of thermal plumes in particle image velocimetry
Authors: Bao Xiyuan , Lithgow-Bertelloni Carolina
Published: November 2024

Optical distortion caused by changes in the refractive index of fluid flow is a common issue in flow visualization using techniques, such as particle image velocimetry (PIV). In thermally driven convection, this distortion can severely interfere with PIV results due to the ubiquitous density and, therefore, refractive index heterogeneity in the fluid. The distortion also varies spatially and temporally, adding to the challenge. We propose a composite filter, the shadow-affected PIV region filter, which combines a series of conventional image filters to address this issue, focusing on optical distortion of thermal plumes in laminar flow. We verify the effectiveness of the filter using both synthetic particle images created from ray tracing and real particle images from the laboratory. For the first time, we effectively mitigate the optical distortion from plumes while preserving the in-plane plume velocity and overall flow pattern, with the PIV data alone. Our filter is efficient and does not require additional measurements, expensive ray tracing, or a large dataset to begin with. It can be extended to separate the flow field and the effect of optical distortion in other fluid experiments when the two components are visually distinct. Additionally, this filter can serve as a baseline algorithm for comparison when developing more advanced methods like neural networks.
Blood flow through a stenosed left anterior descending coronary artery: Evaluation of loss coefficients in one-dimensional fluid–structure interaction model
Authors: Vemula Mohankrishna , Pothukuchi Harish
Published: November 2024

Coronary arterial flow is affected by conditions such as atherosclerosis and stenosis resulting in coronary artery disease. Quantifying the flow fields across arteries is a key aspect in the functional assessment of occlusive arterial disease. An essential aspect of blood flow modeling is the mechanical interaction between the fluid flow and the arterial vessel wall. The present study focuses on the modeling of blood flow within the left anterior descending artery affected with stenosis. A one-dimensional (1D) model was developed to study the transient blood flow characteristics in the artery. The 1D model is coupled with the material tube law to account for the flexibility of the arterial wall. The loss coefficients that account for the local viscous and turbulent losses across the stenosis region are estimated accurately in terms of the varying local cross-sectional area, instead of empirical constants used in the literature. It was observed that the magnitude of viscous losses decreases with an increase in the severity of stenosis. For lower degree of stenosis (<30%), the local turbulent losses are insignificant compared to the viscous losses. The maximum deformation of the vessel wall is ∼0.12mm at t=0.45s for s=70%. During the cardiac cycle (T=0.9s), the artery is observed to be experiencing dilation (Δr>0) in the upstream region, whereas contraction (Δr<0) in the downstream region for all the values of severity (s). A fractional flow reserve of 58.53% was noticed in a stenosed artery of 70% severity.
Ensemble Monte Carlo transport studies of zinc-blende cuprous halides
Authors: Kim Min Hyeok , Kong Byoung Don
Published: November 2024

We present a comprehensive theoretical analysis of intrinsic high-field transport in cuprous halides: CuCl, CuBr, and CuI. Ensemble Monte Carlo transport simulations were performed based on analytical approximations of the multi-valley and three-band electronic structure model. The deformation potentials, extracted from carrier–phonon interaction matrix elements calculated via the Wannier function approach, were employed to determine scattering rates. Our detailed analysis uncovers intriguing transport characteristics based on the complex valence band structures, resulting from spin–orbit coupling and band inversion. Remarkably, the hole mobility in CuI was exceptionally high, reaching up to 193 cm2/V s, while CuCl exhibited unusual temperature dependencies in hole transport. Additionally, the electron mobility in CuI was found to be 254 cm2/V s, indicating a minimal disparity between carrier mobilities, which is advantageous for optoelectronic applications.
Josephson traveling wave parametric amplifiers with plasma oscillation phase matching
Authors: Rizvanov E. , Kern S. , Neilinger P. , Grajcar M.
Published: November 2024

High gain and large bandwidth of traveling-wave parametric amplifier exploiting the nonlinearity of Josephson Junctions can be achieved by fulfilling the so-called phase-matching condition. This condition is usually addressed by placing resonant structures along the waveguide or by periodic modulations of its parameters, creating gaps in the waveguide’s dispersion. Here, we propose to employ the Josephson junctions, which constitute the centerline of the amplifier, as resonant elements for phase matching. By numerical simulations in JoSIM (and WRspice) software, we show that Josephson plasma oscillations can be utilized to create wave vector mismatch sufficient for phase matching as well as to prevent the conversion of the pump energy to higher harmonics. The proposed traveling wave parametric amplifier design has a gain of 15 dB and a 3 GHz bandwidth, which is comparable to the state-of-the-art TWPAs.
Dynamic visualization study of in situ cleaning of polystyrene microparticles off silicon wafer surface
Authors: Wu Qian , Zhao Hui , Liu Haifeng
Published: November 2024

With the improvement of chip performance, the requirements for cleaning the surface of silicon wafers are becoming higher. However, due to equipment and technology, it is difficult to observe the complex motion processes of particles at the microscopic scale. In this paper, an in situ dynamic visualization experiment on the cleaning of Polystyrene Latex (PSL) on the surface of silicon wafers is carried out by using a high-speed camera and image processing software. The mechanical behavior of PSL particles in fluid was investigated on a microscopic scale, and the trajectory and force of the polystyrene particles on the surface of the wafers were visualized, which provided a new perspective for understanding the complex cleaning process. Theoretical models were developed to explain the motion characteristics of the particles by calculating parameters such as van der Waals force, surface tension, and trailing force, and these models provide a theoretical basis for optimizing the cleaning process. There are four particle motion modes in the fluid: (1) interface capture, where the particles on the surface of silicon wafer are trapped by gas–liquid interface under surface tension; (2) particle collision, where the particles captured by the water film collide with the particles on the wafer surface to make the latter leave the silicon wafer; (3) jump attachment, where the particles jump and attach to the surface of the particle group under the action of lift; and (4) wall surface movement, where the particles start up under the action of water flow and then leave the silicon wafer quickly.
Calibration of the Reynolds stress model for turbulent round free jets based on jet half-width
Authors: Turutoglu Cem , Cadirci Sertac , Yilmaz Serdar , Erdem Duygu
Published: November 2024

Reynolds stress model (RSM) turbulence models are expected to yield more accurate numerical results for flows with strong anisotropy, such as round free jets, because they directly solve Reynolds stresses rather than modeling them. However, when computational fluid dynamics (CFD) analyses were performed at moderate jet Reynolds numbers using the isotropization by production (IP) RSM model, it was observed that the calculated jet half-widths, decay constants, and spreading rates differed from experimental results due to uncertainties inherent in the turbulence model. In this study, the closure coefficients of the IP RSM turbulence model were calibrated using a variant of the Multi-Objective Genetic Algorithm based on jet half-width data obtained experimentally in the near-field region of the jet. With the use of appropriate discretization schemes and computational grids, the calibrated coefficient combination for the IP RSM turbulence model showed improved accuracy in modeling jet half-widths at Reynolds numbers of 10 000 and 20 000, reducing the errors of calculated decay constants and spreading rates approximately from 2% to 1% and from 16% to 5%, respectively. A detailed examination of the turbulence budget along the longitudinal axis in the self-similar region revealed that the new model coefficients enhanced the modeling of diffusion term but compromised the advection term. As a result of the altered advection term, increased error margins were observed in turbulence intensity (TI) and velocity distribution along the jet centerline, although dissipation along the axis was improved. Consequently, the modeling error in jet half-width calculations using the CFD method was decreased, enhancing the computational cost-effectiveness of the RSM turbulence model compared to more complex turbulence models.
Iron-molybdenum cofactor synthesis by a thermophilic nitrogenase devoid of the scaffold NifEN
Authors: Payá-Tormo Lucía , Echavarri-Erasun Carlos , Makarovsky-Saavedra Natalia , Pérez-González Ana , Yang Zhi-Yong , Guo Yisong , Seefeldt Lance C. , Rubio Luis M.
Published: November 2024

The maturation and installation of the active site metal cluster (FeMo-co, Fe
7
S
9
CMo-
R
-homocitrate) in Mo-dependent nitrogenase requires the protein product of the
nifB
gene for production of the FeS cluster precursor (NifB-co, [Fe
8
S
9
C]) and the action of the maturase complex composed of the protein products from the
nifE
and
nifN
genes. However, some putative diazotrophic bacteria, like
Roseiflexus
sp. RS-1, lack the
nifEN
genes, suggesting an alternative pathway for maturation of FeMo-co that does not require NifEN. In this study, the
Roseiflexus
NifH, NifB, and apo-NifDK proteins produced in

Escherichia coli

are shown to be sufficient for FeMo-co maturation and insertion into the NifDK protein to achieve active nitrogenase. The
E. coli
expressed NifDK

RS

contained P-clusters but was devoid of FeMo-co (referred to as apo-NifDK

RS

). Apo-NifDK

RS

could be activated for N
2
reduction by addition of preformed FeMo-co. Further, it was found that apo-NifDK

RS

plus
E. coli
produced NifB

RS

and NifH

RS

were sufficient to yield active NifDK

RS

when incubated with the necessary substrates (homocitrate, molybdate, and
S
-adenosylmethionine [SAM]), demonstrating that these proteins can replace the need for NifEN in maturation of Mo-nitrogenase. The
E. coli
produced NifH

RS

and NifB

RS

proteins were independently shown to be functional. The reconstituted NifDK

RS

demonstrated reduction of N
2
, protons, and acetylene in ratios observed for

Azotobacter
vinelandii

NifDK. These findings reveal a distinct NifEN-independent pathway for nitrogenase activation involving NifH

RS

, NifB

RS

, and apo-NifDK

RS

.
Bioenergetic suppression by redox-active metabolites promotes antibiotic tolerance in
Pseudomonas aeruginosa
Authors: Horak Richard D. , Ciemniecki John A. , Newman Dianne K.
Published: November 2024

The proton-motive force (PMF), consisting of a pH gradient and a membrane potential (ΔΨ) underpins many processes essential to bacterial growth and/or survival. Yet bacteria often enter a bioenergetically diminished state characterized by a low PMF. Consequently, they have increased tolerance for diverse stressors, including clinical antibiotics. Despite the ubiquity of low metabolic rates in the environment, the extent to which bacteria have agency over entry into such a low-bioenergetic state has received relatively little attention. Here, we tested the hypothesis that production of redox-active metabolites (RAMs) could drive such a physiological transition.
Pseudomonas aeruginosa
is an opportunistic pathogen that produces phenazines, model RAMs that are highly toxic in the presence of molecular oxygen (O
2
). Under oxic conditions, the phenazines pyocyanin and phenazine-1-carboximide, as well as toxoflavin—a RAM produced by
Burkholderia
species—suppress the ΔΨ in distinct ways across distributions of single cells, reduce the efficiency of proton pumping, and lower cellular adenosine-triphosphate (ATP) levels. In planktonic culture, the degree and rate by which each RAM lowers the ΔΨ correlates with the protection it confers against antibiotics that strongly impact cellular energy flux. This bioenergetic suppression requires the RAM’s presence and corresponds to its cellular reduction rate and abiotic oxidation rate by O
2
; it can be reversed by increasing the ΔΨ with nigericin. RAMs similarly impact the bioenergetic state of cells in (hyp)oxic biofilm aggregates. Collectively, these findings demonstrate that bacteria can suppress their bioenergetic state by the production of endogenous toxins in a manner that bolsters stress resilience.
The chloroplast ATP synthase redox domain in
Chlamydomonas reinhardtii
eludes activity regulation for heterotrophic dark metabolism
Authors: Lebok Lando , Buchert Felix
Published: November 2024

To maintain CO
2
fixation in the Calvin–Benson–Bassham cycle, multistep regulation of the chloroplast ATP synthase (CF
1
F
o
) is crucial to balance the ATP output of photosynthesis with protection of the apparatus. A well-studied mechanism is thiol modulation; a light/dark regulation through reversible cleavage of a disulfide in the CF
1
F
o
γ-subunit. The disulfide hampers ATP synthesis and hydrolysis reactions in dark-adapted CF
1
F
o
from land plants by increasing the required transmembrane electrochemical proton gradient (

Δ

μ
∼

H

+

). Here, we show in
Chlamydomonas reinhardtii
that algal CF
1
F
o
is differently regulated in vivo. A specific hairpin structure in the γ-subunit redox domain disconnects activity regulation from disulfide formation in the dark. Electrochromic shift measurements suggested that the hairpin kept wild-type CF
1
F
o
active, whereas the enzyme was switched off in algal mutant cells expressing a plant-like hairpin structure. The hairpin segment swap resulted in an elevated

Δ

μ
∼

H

+

threshold to activate plant-like CF
1
F
o
, increased by ~1.4 photosystem (PS) I charge separations. The resulting dark-equilibrated

Δ

μ
∼

H

+

dropped in the mutants by ~2.7 PSI charge separation equivalents. Photobioreactor experiments showed no phenotypes in autotrophic aerated mutant cultures. In contrast, chlorophyll fluorescence measurements under heterotrophic dark conditions point to an altered dark metabolism in cells with the plant-like CF
1
F
o
as the result of bioenergetic deviations from wild-type. Our results suggest that the lifestyle of
C. reinhardtii
requires a specific CF
1
F
o
dark regulation that partakes in metabolic coupling between the chloroplast and acetate-fueled mitochondria.
An outcome-defining role for the triple-helical domain in regulating collagen-I assembly
Authors: Yammine Kathryn M. , Li Rasia C. , Borgula Isabella M. , Mirda Abularach Sophia , DiChiara Andrew S. , Raines Ronald T. , Shoulders Matthew D.
Published: November 2024

Collagens are the foundational component of diverse tissues, including skin, bone, cartilage, and basement membranes, and are the most abundant protein class in animals. The fibrillar collagens are large, complex, multidomain proteins, all containing the characteristic triple helix motif. The most prevalent collagens are heterotrimeric, meaning that cells express at least two distinctive procollagen polypeptides that must assemble into specific heterotrimer compositions. The molecular mechanisms ensuring correct heterotrimeric assemblies are poorly understood – even for the most common collagen, type-I. The longstanding paradigm is that assembly is controlled entirely by the ~30 kDa globular C-propeptide (C-Pro) domain. Still, this dominating model for procollagen assembly has left many questions unanswered. Here, we show that the C-Pro paradigm is incomplete. In addition to the critical role of the C-Pro domain in templating assembly, we find that the amino acid sequence near the C terminus of procollagen’s triple-helical domain plays an essential role in defining procollagen assembly outcomes. These sequences near the C terminus of the triple-helical domain encode conformationally stabilizing features that ensure only desirable C-Pro-mediated trimeric templates are committed to irreversible triple-helix folding. Incorrect C-Pro trimer assemblies avoid commitment to triple-helix formation thanks to destabilizing features in the amino acid sequences of their triple helix. Incorrect C-Pro assemblies are consequently able to dissociate and search for new binding partners. These findings provide a distinctive perspective on the mechanism of procollagen assembly, revealing the molecular basis by which incorrect homotrimer assemblies are avoided and setting the stage for a deeper understanding of the biogenesis of this ubiquitous protein.
Correlations and signaling in the Schrödinger–Newton model
Authors: Aleksander Gruca Jacek , Kumar Ankit , Ganardi Ray , Arumugam Paramasivan , Kropielnicka Karolina , Paterek Tomasz
Published: November 2024

The Schrödinger–Newton (SN) model is a semi-classical theory in which, in addition to mutual attraction, massive quantum particles interact with their own gravitational fields. While there are many studies on the phenomenology of single particles, correlation dynamics in multipartite systems is largely unexplored. Here, we show that the SN interactions preserve the product form of the initial state of a many-body system, yet on average agreeing with classical mechanics of continuous mass distributions. This leads to a simple test of the model, based on verifying bipartite gravitational evolution towards non-product states. We show using standard quantum mechanics that, with currently accessible single-particle parameters, two masses released from harmonic traps get correlated well before any observable entanglement is accumulated. Therefore, the SN model can be tested with setups aimed at observation of gravitational entanglement with significantly relaxed requirements on coherence time. We also present a mixed-state extension of the model that avoids superluminal signaling.
Charged Nariai black holes on the dark bubble
Authors: Danielsson Ulf , Van Hemelryck Vincent
Published: November 2024

In this paper, we realise the charged Nariai black hole on a braneworld from a nucleated bubble in AdS5, known as the dark bubble model. Geometrically, the black hole takes the form of a cylindrical spacetime pulling on the dark bubble. This is realised by a brane embedding in an AdS5 black string background. Identifying the brane with a D3-brane in string theory allows us to determine a relation between the fine structure constant and the string coupling,

α
EM

=

3
2

g
s

, which was previously obtained for a microscopic black hole. We also speculate on the consequences for the Festina Lente bound and neutrino masses.
Riemannian manifold-aided data-driven diagnosis of photovoltaic hot spots
Authors: Wu Lingrui , Yi Hui , Yang Chen , Hongtian Chen and
Published: November 2024

This paper proposes a novel data-driven approach for hot-spot fault detection in photovoltaic (PV) modules, utilizing a curved Riemannian manifold (RM) to characterize the sample space. The proposed method detects hot spots in PV systems by mining geometric features in high-dimensional data. The RM-based method combines the geometric properties of RMs for fault detection. In addition, it also provides information about the severity of the hot spots. The proposed method has three main advantages: (1) it is capable of actively learning fault characteristics and can be applied to diagnose various degrees of hot spots; (2) unlike other data-driven methods, the proposed method considers non-Euclidean spatial data features, which further improves the accuracy of the method and reduces the false alarm rate; (3) it does not rely on mathematical models or expert knowledge, making it able to meet the real-time monitoring needs of actual PV systems. The effectiveness and superiority of the proposed approach are verified through 12 sets of hot spots tests conducted on a PV experimental platform.
Several families of entanglement criteria for multipartite quantum systems based on the generalized Wigner–Yanase skew information and variance
Authors: Hong Yan , Hao Xinlan , Gao Limin
Published: November 2024

Quantum entanglement plays a critical role in many quantum applications, but detecting entanglement, especially in multipartite or high-dimensional quantum systems, remains a challenge. In this paper, we propose several families of entanglement criteria for detecting entanglement in multipartite or high-dimensional quantum states by the generalized Wigner–Yanase skew information

I
s

(
ρ
,
X
)

for

−
1
⩽
s
⩽
0

and variance. We also reveal a complementary character between the criteria based on the generalized Wigner–Yanase skew information and an alternative one based on variance through specific examples. We illustrate the merits of these criteria and show that the combination of the entanglement criteria has a stronger detection capability, as it is capable of detecting entangled states that remain unrecognized by other criteria.
Strengthening Study on Microsphere Particle Peening for Flexspline Surface of Harmonic Reducer
Authors: Zhang Feifei , Gong Taimin , Huang Songkai , He Kai , Xu Hui
Published: November 2024

The service stability of the flexspline directly affects the service life of the harmonic reducer. Its main failure modes are fatigue fracture of the flexspline, damage of the flexible bearing, tooth wear or transmission slip, the above problems are often sprouted and developed from the surface. Researches show the novel surface treatment technology-Microsphere Particle Peening can significantly enhance the surface performance of the flexspline of the harmonic reducer, and thus improve its fatigue resistance. Therefore, studying this novel shot peening technology has significant scientific significance and practical value. In this paper, Microsphere Particle Peening is adopted to strength the flexspline surface and the effects of three different Microsphere Particle Peening conditions on the surface performance of the flexspline is analyzed. The research results indicate that Microsphere Particle Peening technology can introduce larger residual compressive stress, reduce the surface roughness, increase the surface hardness, improve the microstructure morphology, and effectively control the deformation amount of the flexspline by controlling the processing parameters of Microsphere Particle Peening. Therefore, Microsphere Particle Peening technology has broad engineering application prospects in the surface strengthening of precision components.
Fabrication of Self-powered Silicon Microneedles for Transdermal Drug Delivery
Authors: Wu Jiajun , Li Xinhui , Yan Xiaoxiao , Tang Gang , Li Yuwen , Li Zhibiao
Published: November 2024

Transdermal drug delivery has been widely studied in recent years. Compared with other methods of drug delivery, this method has many advantages, such as convenient, improving patient compliance and avoiding first-pass effect. However, the low efficiency of this method needs to be overcome. In this paper, a micro-invasive transdermal drug delivery mechanism with synergic coupling of microneedle force field and triboelectric field is proposed, which can enhance the efficiency of transdermal drug delivery and is easy to operate and use. First, a silicon solid microneedle array was fabricated by micromachining technology, and its size parameters could be flexibly adjusted. Second, a metal layer with microstructure was fabricated on the back of the microneedle by sputtering technology as the positive friction layer of the triboelectric structure. Last, the microneedle and the triboelectric structure were combined into a single composite structure by using FPC wires. The experimental results showed that the transdermal amount increased with the increase of external excitation force, frequency and the number of microneedle arrays. Under the same conditions, the skin penetration of the two mechanisms combined was 3-8 times higher than that of the single use.
Failure Analysis of Burst Tube Caused by Corrosion Thinning of the Tube Wall of Boiler Economizer
Authors: Liu Haiyun , Xiang Zhi , Wang Lei , Wu Zuhang , Wang Yuan
Published: November 2024

A boiler economizer is in continuous operation during several burst pipes. Burst tubes are located near the elbow below the weld, and the weld on both sides of the tube wall is thinning seriously. There is a flue gas formation vortex in the furnace chamber; the outer wall of the tubes is thicker ash, and fins and tubes are corroded to varying degrees. This study employed meticulous macroscopic observation, precise chemical composition analysis, detailed metallography, advanced scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) to determine the causes of the coal economizer tube burst and tube wall thinning, ensuring the accuracy of the findings. The chemical composition, microstructure, and grain size of the base material met the requirements of the relevant standards. The heat-affected zone and weld seam show the Widmannstatten structure, a superheated tissue caused by excessive heat input during welding. The outer wall of the pipe corrosion is more serious, resulting in serious wall thinning, and ultimately, the pipe bursts, unable to withstand the pressure inside the pipe. It was eventually determined that the cause of the pipe burst was that the operating temperature of the economizer was close to the dew point, and the flue gas contained sulfur dioxide, sulfur trioxide, and hydrogen chloride that met water vapor at that temperature to form acid. Acid on the outer wall of the pipe was caused by flue gas dew point corrosion, seriously causing the pipe wall to thin. When the pipe wall is thinned to a certain extent due to corrosion, it cannot withstand the pressure inside the pipe, and rupture will occur.
Evolution of Microstructure and Hardness during Carburization Heat Treatment of Heavy-duty Gear Steels: Numerical Prediction and Experimental Study
Authors: Du Zunzhong , Wu Zehua , Chen Xuan , Chen Qiyuan , Yuan Yuedong , Wang Xiaonan , Chen Jialu
Published: November 2024

In order to solve the problems of long process cycle, low efficiency and high cost in the carburization heat treatment process of 18Cr2Ni4WA heavy-duty gear steel. The carbon concentration distribution of 18Cr2Ni4WA steel under conventional carburizing process at 930℃ was studied by combining numerical simulation with experimental research. The results show that the carbon concentration distribution predicted by the simulation is in good agreement with the experimental results. The microstructure of the surface layer after low-temperature tempering consists mainly of fine acicular tempered martensite, while the core consists mainly of lath tempered martensite and bainite. The increase in hardness after carburization is mainly attributed to the solid solution strengthening of the carbon atoms. The increase in hardness after cryogenic treatment is mainly attributed to the precipitation strengthening of the carbides. In addition, compared to the conventional carburization at 930°C, the high temperature carburizations at 950°C and 970°C reduced the carburization time by 37.2% and 53.5%, respectively.
Ship Forebody Optimization Based on Rankine Source Method
Authors: Song Shengyao , Zhang Baoji
Published: November 2024

The shape of the ship’s forebody has a greater impact on the ship’s resistance, and a reasonable optimization of the forebody can play a role in reducing the propulsion power and optimizing the resistance performance. Under the premise of Rankine source method of potential flow wave theory as the theoretical basis, SHIPFLOW software is used as the calculation tool, and CAESES software is used as the optimization tool to study the optimal design of the ship with minimum wave resistance. In the optimization process, a real ship is taken as the object, and the optimal solution of the rising wave resistance coefficient is calculated with the rising wave resistance coefficient as the objective function and the ship speed and displacement as the constraints. The real ship is selected as the mother ship, the parameters of the hull shape are taken as the design variables, and the shape of the forebody is optimized by the Lackenby shift method, so as to obtain a ship shape with less wave resistance at the same speed and within the displacement limit. The results show that the improved ship shape has obvious effect of reducing the wave resistance, which verifies the effectiveness and feasibility of this method for ship shape optimization
Forecast, analytical and trend analysis of the development of the agro-industrial complex of Russia in the main agri-food markets as an area of state strategic guidelines
Authors: Moroz O N , Medvedsky D A
Published: November 2024

The modern structure of the Russian agro-industrial complex has the properties of consolidation, expansion and prevalence of agricultural organizations and agricultural holdings, as evidenced by the factor of their provision for about two-thirds of the total agricultural production. This circumstance states the growing dominance of large agricultural business and the progressive evolution of the agricultural sector, as well as the reduction in the importance of individual farms of the population. In the course of the study, the current state of development of the agro-industrial complex of Russia is considered, a forecast, analytical and trend analysis of the development of the domestic agro-industrial complex is carried out through the prism of the fundamental agri-food markets and the contours of the subsequent progress in the development of the agricultural sector in the context of the evolving restructuring of the social, economic and political situation are determined. The novelty of the research lies in the presentation of forecast estimates and trends in the development of the main agri-food markets of the Russian agro-industrial complex, which determine the presumptive transformation of the agrarian mechanism of Russia in the medium and long term: destabilization of international political and trade-economic cooperation, intensification of economic restrictive measures, as well as fundamentally new state priorities. The agricultural sector of the economy tends to react extremely sharply to the current situation in recent years, manifested in unstable international economic relations and foreign policy crises, which directly negatively affects the conditions for the functioning of the agricultural business. The presented forecast scenario for the development of agri-food markets will contribute to the formation of directions for state strategic management, planning and regulation of the agro-industrial complex for the medium and long term.
Assessment of the regional development of the agricultural sector in the context of digital transformation
Authors: Kivarina Mariya , Yurina Nataliya
Published: November 2024

The current stage of agricultural development is characterized by its susceptibility to the latest changes caused by the introduction of digital technologies into the processes of organizing economic activity. This leads to the need for an economic assessment of the state of the industry to determine its readiness for transformation in the context of digitalization. This issue is particularly relevant for the regional economy, in which high-tech digital agriculture can become a source of growth in the ecosystem of innovative development of the agro-industrial complex of the country. Therefore, the purpose of the article is to study certain aspects of the functioning of agriculture in the Novgorod region, which act as determinants of the development of the industry in the context of digitalization. The paper identifies the factors influencing the digital transformation of agricultural organizations, as well as identifies the specifics of the functioning of the industry in the region during the transition to a digital business model.
State and prospects for the development of hemp cultivation in the Russian Federation
Authors: Bikbaeva Gulnur , Islamgulov Damir , Lubova Tatiana
Published: November 2024

The article discusses the prerequisites for the revival of the hemp industry. The reasons for the reduction in hemp sown areas and the state of hemp production in different years are shown. The characteristics of this crop as a raw material for the processing industry are given. Numerous types of products obtained from hemp during processing are given. The prospects for the further development of hemp through the federal target program “Development of breeding and seed production of industrial crops in the Russian Federation” are considered. Data are presented on the sown areas on the territory of the Russian Federation from 2010 to 2023, on the territory of the Republic of Bashkortostan from 2021 to 2023.
Digital Metrics of Agro-Industrial Complex: Intelligent Monitoring of Grain Production
Authors: Arinichev I V , Sidorov V A , Arinicheva I V
Published: November 2024

The article examines the basic conditions for the digitalization of grain production monitoring, including data collection organization, IT infrastructure selection, as well as changes in organizational culture and personnel training. The digitalization of the monitoring process involves the use of modern technologies such as neural networks and computer vision to enhance the accuracy and promptness of crop condition monitoring. Special attention is given to the implementation of digital solutions and overcoming barriers that hinder the digital transformation of grain fields. The principles of monitoring organization presented in the article lay the foundation for efficient and sustainable production, ensuring the quality and safety of grain products, contributing to the strengthening of the country’s food security, enhancing the resilience of the agro-industrial complex, and can become a conceptual basis for the development of the intelligent component of grain production.
Productive features of the first heifers of the red steppe breed under different systems of housing and forming of production groups
Authors: Elzhirokova Zalina , Yurin Denis , Gneush Anna , Tletseruk Irina , Ulimbashev Murat
Published: November 2024

The purpose of the research is to establish the productive qualities of the first heifers of the red steppe breed with different technologies of housing and forming a production group of newly-calved cows. Intergroup differences in the milk yield of the first heifers were established, which amounted to 176 kg of milk in favor of individuals who lactated separately from adult cows (P>0.95). The yield of protein and fat during lactation also prevailed in the experimental group of heifers by 3.5-3.8%. According to the milk content index, the first heifers kept together with adult livestock were inferior to the individuals of the experimental group by an average of 1.4%. The differences in the content of first heifers in the summer period were expressed in the superiority of milk yield of first heifers, which were grazed on pastures, during the pasture period at the level of 262 kg (P>0.95), provided them with superiority in milk production for the entire period of first lactation by an average of 289 kg of milk (P>0.95), as well as in yield milk fat and protein. As a result, the milk content index of the first heifers of the experimental group reached 1225 kg against 1161 kg in the control (P>0.95).
Productivity and resistance of sheep depending on the grazing period duration
Authors: Konik Nina , Kapitonova Elena , Krasnova Oksana , Kubatieva Zalina , Brantova Marzyat
Published: November 2024

The purpose of the research is to establish the productive qualities and resistance of the sheep organism at different periods of keeping sheep on pastures. Studies on improving the pasture use system were carried out on three groups of sheep with the beginning of the pasture season on April 25: Group I – with the end of the pasture season on October 15, II – on November 15, and III – on December 15. The data obtained indicate that the females kept on pastures for a longer time exceeded their peers of other groups by 1.6-2.0 kg in live weight. Before being driven to pastures on April 20, their live weight also turned out to be higher by 0.8-1.2 kg, and during their stay on pastures – by 0.7-1.6 kg, which indicates the expediency of longer grazing of sheep. In terms of live weight, the superiority of late weaning compared to the average was 1.25%, over group I (early term) – 5.23% (P>0.95). The blood of young ewes with a long grazing period contained more leukocytes, gamma globulins, erythrocytes and, most importantly, hemoglobin.
Features of growth and meat productivity of Hereford and Kalmyk bull calves
Authors: Kairov Valery , Kapitonova Elena , Krasnova Oksana , Konik Nina , Kubatieva Zalina
Published: November 2024

The purpose of the research is to study the peculiarities of growth and meat productivity of Hereford and Kalmyk bull calves bred in the conditions of the foothill zone of the Central Caucasus. The object of the research were Hereford (group I) and Kalmyk (group II) bull calves. A more complete realization of the genetic growth potential of Hereford cattle took place by the end of the research – at the age of 18 months, when the superiority of animals of this breed over the Kalmyk breed representatives was 22.6 kg (P>0.99). Heavier hot carcasses of Herefords with a difference of 18.8 kg (P>0.99) testified to their greater fullness. As a result of the differences in the mass of the hot carcass and internal fat, the highest slaughter weight and its yield were obtained from representatives of the Hereford breed, who surpassed their peers of the Kalmyk breed in these indicators by an average of 21.4 kg (P>0.99) and 2.8 abs.% (P>0.99), respectively.
Efficiency of precision farming systems application in the implementation of main tillage
Authors: Moisseyenko O V , Ivanchenko P G , Voitsekhovskaya L A , Jabassova Zh G , Kukhar V S
Published: November 2024

The main direction of crop production development is transformation from traditional agro-technologies to resource- and energy-saving technologies. One of the options of developing resource- and energy-saving technologies is precision farming technologies. Implementation of these technologies will provide optimal results in crop production. However, the use of tractors, agricultural machines and combines in the system of effective precision farming is possible, based on the analysis and substantiated conclusions of modern scientific and technical information. As well as the possibilities for specific natural and production conditions. Thus, the purpose of the study is to increase the efficiency of precision farming systems in the implementation of main tillage. The article presents the results of comparative tests of disc ripper “John Deere” (model 2720) in combination with tractors “Claas” (model AXION 950). The tests were conducted in the process of main tillage in the system of precision agriculture. The fields of “Agricultural Experimental Station “Zarechnoye” LLP, located in Kostanay region, Kostanay oblast, were chosen as a testing ground. During the comparative testing process, the objective was to determine the impact of the automatic driving system “Claas GPS PILOT” on certain indicators, in particular agrotechnical, technical-operational and economic indicators of their functioning. The conditions of comparative tests are typical for farms located in the areas of Northern Kazakhstan producing grain crops. The results of tests demonstrated that the application of automatic driving system “Claas GPS PILOT” on main tillage, disc ripper “John Deere” (model 2720) in combination with a tractor “Claas” (model AXION 950) allows to increase the working width of the machine by 24 cm, increase the shift productivity of the machine by 4.8%, reduce specific fuel consumption by 4.9%, specific energy costs by 2.9-6.1%, total cash outlay by 521.0 tenge/ hectare and get annual savings of total cash outlay of 294.5 thousand tenge.
To determine the cut height of fallen stems
Authors: Salikhova M N , Aleksandrov V A , Galchak I P , Aleksandrova N A , Kukhar V S
Published: November 2024

A significant part of the harvested crops lies down by the beginning of harvesting, and the harvesting of fallen bread cereals is accompanied by an increase in grain losses. The productivity and quality of the cutting devices of harvesting machines, which are used for harvesting crops, largely depend on the cut height of the fallen stems. It was found out that with an increase in the cut height, grain losses increase, and with its decrease, the efficiency of agricultural machinery decreases due to clogging of mechanisms with plants and soil. The article considers the analytical dependencies between the characteristics of the height of the cut stems, the soil surface and the cutting machine in its general movement across the field. The basic formulas of such dependencies are given.
Features of organic agriculture development in Asian countries
Authors: Khoruzhy L I , Kagirova M V , Kirillova S S , Romantseva Yu N , Anokhin I A
Published: November 2024

The implementation of Sustainable Development Goals stimulates the use of new innovative technologies in production processes of the most resource-intensive types of economic activity in most countries of the world. The modern agricultural sector, which uses land and water resources to ensure food security in countries, aims to preserve soil fertility, the quality of water resources, air and biodiversity. That is why organic agriculture is gaining popularity not only in developed, but also in lower-income countries, including Asian countries. In recent years, countries such as China and India have increased the production of various types of products several times; moreover, their consumption is constantly increasing, which is the basis for achieving the goal of preserving the health of the nation. The study is aimed at identifying natural and economic factors in the development of production, consumption and export of organic products; existing risks. The choice of the object of study is due to the fact that China, India and Indonesia are the leading countries, among the top ten countries in terms of population, these countries are large in extent, in other words, the size of their territory allows them to produce various types of agricultural products; Vietnam and Thailand were chosen due to the fact that the countries are quite unique in terms of climatic conditions, which is why they produce unique types of products and have been actively increasing the production of organic products in recent years. Based on the methods of structural and comparative analysis, aligning time series, stable trends towards an increase in export volumes were identified, and the reasons for the increase in the production of organic products were substantiated.
Microplastics and Climate Change: Analyzing the Environmental Impact and Mitigation Strategies
Authors: Abdullayeva Maya , Yaqubov Ramil
Published: November 2024

Plastics have become integral to modern society due to their versatility and economic benefits, resulting in unprecedented global production levels. However, this convenience comes at a significant environmental cost, with plastic pollution posing severe threats to ecosystems and human health. Amidst growing concerns, the COVID-19 pandemic has exacerbated the plastic pollution crisis, particularly with the surge in single-use plastic consumption. Moreover, the insidious role of plastics in exacerbating climate change is increasingly recognized, with plastic-related greenhouse gas emissions presenting a significant challenge to global climate goals. This article analyzes the direct and indirect contributions of plastic to greenhouse gas emissions, encompassing various waste management methods and the production lifecycle of plastics. Through a comprehensive assessment, the urgent need for intervention strategies to mitigate the consequences of plastic pollution and its climate-related impacts is determined. Efforts to reduce plastic’s impact on climate include promoting bio-based alternatives, transitioning to low-carbon production methods, banning single-use plastics, and improving waste management practices. By adopting these strategies, we can address the detrimental impact of plastic pollution on our planet and climate, moving towards a more sustainable future.
Judges
Authors: He Xin
Published: November 2024

Chapter 2 scrutinizes the judges’ work, exploring their backgrounds, responsibilities, and aspirations. It highlights the impact of recent legal professionalism reforms, which have increased state control over judges, making them more accountable than independent. The chapter distinguishes between legitimate and illegitimate extralegal influences on judges, arguing that the decline of the latter has led to an increase in the former. It examines the impacts of these influences on judges’ workloads, promotions, and prestige, and notes a shift from hierarchical to panoptic control. Overall, Chapter 2 provides a vivid and penetrating analysis of the experiences and challenges facing judges in China’s evolving judicial system.
People’s Assessors
Authors: He Xin
Published: November 2024

Chapter 3 focuses on the role of people’s assessors in China’s judicial system. It examines recent reforms aimed at enhancing their decision-making power and explores the impact of the new Assessors’ Law. The chapter highlights the dilemma facing the institution, as the regime wants to present an image of judicial democracy but cannot afford to lose control. Despite significant investments and efforts to improve the assessors’ role, progress remains limited. The impact of lay participation is rather limited. The lay assessors deliberate together with the judges and thus are heavily influenced by them; more importantly, the state tightly controls the courts’ decision-making process, further minimizing lay assessors’ impact. Overall, Chapter 3 provides a sharp analysis of the challenges facing people’s assessors in China’s evolving judicial system.