bluuebunny/crossref_metadata_2025 huggingface dataset:
Photocatalytic mineralization of chlorpyrifos using CdS/MAX-phase nanocomposites and detailed investigation of the mechanism and degradation pathways
Authors: Patel Jinal , Gaur Rama , Shahabuddin Syed , Tyagi Inderjeet
Published: October 2024

Synthesis of CdS/MAX-phase nanocomposites by a thermal decomposition approach and their utilization for the photocatalytic mineralization of CPY from aqueous solution.
Feature selection and data‐driven model for predicting the remaining useful life of lithium‐ion batteries
Authors: Zhang Yuhao , Han Yunfei , Cai Tao , Xie Jia , Cheng Shijie
Published: October 2024

To ensure long and reliable operation of lithium‐ion battery storage workstations, accurate, fast, and stable lifetime prediction is crucial. However, due to the complex and interrelated ageing mechanisms of Li‐ion batteries, using physical model‐based methods for accurate description is challenging. Therefore, building data‐driven models based on direct measurement data (voltage, current, capacity, etc.) during battery operation may be a more effective approach. This paper employs a time series analysis of discharge capacity/voltage curves to perform feature predication. The goal is to predict the state of health using a short‐term model and the remaining useful life of batteries using a long‐term iterative model. The validity of this method is verified using the open‐source MIT battery dataset. Comparisons with models reported in the literature demonstrate that this method is generalisable and ensures accuracy across a wider range of predictions.
Study on transient electric shock characteristics between human body and metal clothes hanger on residential platform near UHV AC transmission lines
Authors: He Wangling , Zhang Ke , Wan Baoquan , Zhao Jun , Zhang Yinlu , Liu Yunpeng , Zhou Dasen , Zhang Tianyu
Published: October 2024

With the development of ultra‐high‐voltage (UHV) and extra‐high‐voltage transmission lines in China, the transmission lines are gradually approaching the residential areas. The phenomenon of induced electric shock caused by electrostatic induction effect can cause dissatisfaction and complaints from nearby residents. In this paper, a full‐size steel‐framed residential test platform was constructed near a 1000‐kV UHV alternating current (AC) transmission line, the transient shock characteristics of human bodies and metal hangers in different scenarios was investigated, then the relationship between transient shock energy and subjective perception of the human body was discussed. In addition, the shielding effect of shielding wires for transient electric shock situations is analyzed. It was found that the worst‐case scenario occurred when the grounded human body came into contact with the insulated metal clothes hanger, even eliciting a noticeable sensation of pain. In addition, increasing metal shielding wire number has a significant effect on weakening induced electric shocks.
Real‐time reliability evaluation method for IGBT module in MMC based on junction temperature and bond wire failure online monitoring
Authors: Dongye Zhonghao , Zhang Wuyu , Qi Lei , Gu Bowen , Shen Hong , Zhang Xiangyu , Cui Xiang
Published: October 2024

The lack of an MMC reliability evaluation approach that incorporates data on essential components' health monitoring in the already related research prevents reliability from being further improved. Therefore, this article proposes a real‐time reliability evaluation method of the multi‐state IGBT module in MMC through iterative calculation of the Markov chain model. The degradation process of the IGBT module is divided into multiple states based on the monitored bond wire failure, and the failure rate of the IGBT module is updated in real time using the accumulated monitoring data of junction temperature. The proposed method can more accurately reflect the real state of MMC compared with the binary state evaluation method. Besides, a multi‐channel high‐speed data acquisition board is designed to measuring the gate voltage and collector voltage of the IGBT for the health evaluation of IGBT modules in MMC; the typically measured results validate the effectiveness of the data acquisition board.
An optimal parameter design method for cascaded H‐bridge multi‐level converter in wind farm
Authors: Xiao Huagen , Zhang Yongxi
Published: October 2024

The cascaded H‐bridge multi‐level converter is the main topology of high‐voltage and high‐capacity converter in renewable energy power generation, energy storage system and reactive power compensation equipment. The parameter design of cascaded H‐bridge multi‐level converters directly determines the material cost and performance. Taking the output current distortion rate and the ripple voltage of the capacitor of the cascaded H‐bridge multi‐level converter as the constraint conditions, this paper proposes an overall parameter optimal design method of the cascaded H‐bridge multi‐level converter based on the optimization of the total material cost. Finally, the effectiveness of the proposed parameter design method is verified by the simulation result.
Evaluation of radon concentrations in drinking water available in Baghdad Governorate markets, Iraq
Authors: Abdulkhaleq Nour A. , Kareem Dawood Salwah , Mohammed Qader Kzal , Yakoob Taher Sally
Published: October 2024

Radon dust was measured in 15 samples Results: The mass of radon in potable water from Baghdad Governorate markets ranged from 3.5 (Bq/m3) to 74 (Bq/m3) with a mean value of 26.6 ±25.311 (Bq/m3). illustrated The annual effective dose (Ed) results for each group (3 months, 10 years, 15 years, and adults). The Ed values for the 3-month age group range from 0.10 to 0.88 μSv/year. as seen for the 10-year age group they range from 0.02 to 0.96 μSv/year; as seen for the 15-year age group they range from 0.13 to 0.98 μSv/year and as seen for the adult age group they range from 0.07 to 0.92 μSv/year Results indicated that the content of radon- 222 in healthy drinking water in Baghdad's market was within permissible limits set by the World Health Organization in 2008 and United Nations Scientific Committee on the Effects of Atomic Radiation in 2000. The annual effective dose of drinking water for infants in Baghdad's market is also within these limits.
Forecasting the environmental safety of water resources using neural networks
Authors: Evsuykov Dmitry , Degtyareva Ksenia , Boyko Andrei , Kukartsev Anatoliy
Published: October 2024

In this study, a neural network model has been developed to analyze the suitability of water based on its chemical and physical characteristics. The ecological significance of the task is due to the need for effective monitoring of the quality of water resources, which are an essential element of ecosystems and directly affect human health and the environment. The model has demonstrated a high accuracy of 87%, which confirms its effectiveness for automated analysis of water quality. The results of the study indicate the importance of parameters such as pH and concentration of pollutants for determining the suitability of water. The developed model can be implemented into environmental monitoring systems, providing more rapid and accurate detection of pollution and improving decision-making processes in water resources management.
Predicting tree survival in agroforestry systems using machine learning classification algorithms
Authors: Kravtsov Kirill , Kukartsev Vladislav , Stepanova Elina , Soloveva Tatiana
Published: October 2024

This article discusses the application of machine learning algorithms to predict the survival of trees in agroforestry systems. Forests play a key role in maintaining ecological balance and biodiversity, but their survival is subject to many threats, including climate change, anthropogenic impacts, diseases and pests. The study used a dataset containing data on various factors affecting the survival of trees, such as the content of phenols, the presence of arbuscular mycorrhizal fungi (AMF), lignin and non- structural carbohydrates (NSC). The classification model was built using the C4.5 decision tree algorithm, which demonstrated high accuracy (86.02%) in predicting the survival of trees. Correlation analysis revealed that phenols and AMF are the most significant factors determining the survival of trees. These results highlight the importance of biochemical and symbiotic factors for tree health. The article also discusses the importance of various factors and suggests directions for future research aimed at improving the management of forest ecosystems in agroforestry systems. The use of machine learning methods allows not only to improve the accuracy of forecasting, but also to develop more effective strategies for the conservation and sustainable management of forests.
Comparative characteristics of soddy-podzolic plowed and fallow lands for the organic farming
Authors: Ymma M. , Naumov V.D. , Strelkov D.A. , Sedykh V.A. , Kamennih N.L. , Shmakova K.A. , Radchenko E.P.
Published: October 2024

Agricultural lands are being actively withdrawn from the circulation. These lands are now fallow lands and go through the natural and anthropogenic processes like soil formation, tinning, bogging, swarding, weediness with bushes, weed, as well as with scrubs of birches and pines. Hence, the soil formation and functioning conditions and their ecological functions have significantly changed. Natural processes of vegetation recovery begin on the abandoned agricultural lands which leads to the recovery of forests. As a result, there occur soils which differ from the climatic type and arable soils. Practically all existing now statistic data can be summarized by saying that the character of changes in the chemical properties is closely related to the properties both of the soil, age of the fallow land and biocenosis. Taking into account patterns of reclamation preserve under the forest quite long in particular high concentration of nutritional chemicals and humus. The main objective of this investigation is to analyze the changing patterns of the composition and properties of soils which are not used in agriculture for a long time, for instance, soddy- podzolic plowed and fallow lands of the Mozhaisky district of the Moscow Region. The authors stated after the investigation that the soddy-podzolic plowed and fallow soils of different age differ insignificantly in the power of the humus-accumulated horizon (from 2.1% to 2.3%) and the distribution character of humus along the profile. Long existence of soils under fallow is not followed with changes in such properties as the reaction of environment, sum of absorbed bases, the hydrolytic acidity. On the arable lands the coefficient of soil fertility is 0.62, on the fallow ones up to 10 years old ⎯ 0.63 and on the fallow ones between 10 and 20 years old ⎯ 0.64.
Structure and calculations of the test stand for piston hydraulic cylinder trials
Authors: Rybak Alexander , Meskhi Besarion , Rudoy Dmitry , Olshevskaya Anastasiya , Pelipenko Alexey , Serdyukova Yuliya , Teplyakova Svetlana , Ovchinikov Ivan , Prutskov Alexey
Published: October 2024

When testing finished products of mechanical engineering, including hydraulic engineering, a large amount of energy has to be expended, which, as a rule, is irretrievably lost, while contaminating the environment. In this regard, the problem of energy saving in testing processes is given great attention. One of the directions of energy saving in testing of hydraulic machines is energy recovery. The purpose of the work is to develop the structure and circuit diagram of the test bench for piston hydraulic cylinders, providing the recovery of part of the energy used for testing. Piston hydraulic cylinders are widely used in hydraulic drives of mobile machines and in various stationary technological equipment. Working time of a hydraulic cylinder up to failure is regulated by the manufacturer, as a rule the number of operation cycles or the total length of the hydraulic cylinder piston passage is indicated. In the process of achieving the goal proposed structure of the test bench for piston hydraulic cylinders and developed its schematic diagram. On the basis of application of the theory of volumetric stiffness the modeling of the stand functioning process is made. A computer program based on the SimInTech software package has been developed, preliminary calculations of the test bench functioning process have been made, and the characteristics of the test bench functioning have been obtained.
Properties of ceramic coatings in engine cylinder liners restoration using combined technology
Authors: Popov Nikita , Chavdarov Anatoly
Published: October 2024

In the course of vehicle operation with internal combustion engines, due to various reasons, defects occur on the cylinder mirror, resulting in the need for repair work to eliminate them. For non-cylinder blocks most often requires replacement with a new block, which is economically very costly. The technologies of liner restoration are very diverse and their application depends on the available equipment and material of the liner. The aim of the work is to develop a new combined technology for the restoration of liners and cylinder blocks regardless of the material for their manufacture. As a technology of restoration of the geometry of the mirror of the liner the method of cold gas dynamic spraying with the use of aluminum powder is considered. Subsequent application of the plasma electrolytic oxidation (PEO) technology makes it possible to obtain on the mirror a ceramic coating with thickness of 80-100 microns, which is sufficient for long-term operation of the internal combustion engine. On the basis of GZ-195N liner the technology of cylinder mirror restoration was worked out and the process of plasma electrolytic oxidation (PEO) was carried out. Research has shown that the hardening of the coating occurs to the depth of 100 microns required by the technology. The wear resistance of the coating exceeds the wear resistance of the reference sample, its wear factor is 1.27 times less than that of the reference pair. The possibility of using the technology of aluminum coating by cold spray on any metal makes the combined technology of cylinder liner repair applicable to achieve the desired result - to restore the performance of the cylinder block or liner and increase their wear resistance. The obtained positive results require the development of industrial technology of combined coating and experimental testing on a running engine.
Rice husk ash and zeolite-siliceous rock as sources of amorphous silicon dioxide
Authors: Gotlib Elena , Mishagin Kirill , Gabdulkhayev Kamil , Sokolova Alla
Published: October 2024

The present article is referred to the study of amorphous analogs of silicon dioxide obtained from raw materials of plant and fossil origin available on the domestic market. Silicate fillers of crystalline structure are less preferrable for filling ceramic and polymer composite materials due to their lower reaction capacity. Rice husk ash, a large-tonnage agricultural waste, and zeolite-siliceous rock of Tatar-Shatrashanskoye deposit were used as sources of amorphous silicon dioxide in the given study. Having analyzed the received experimental data, the authors concluded that application of both industrially produced silicon dioxide derived form the rice husk ash and zeolite-siliceous rock by the solid phase method allows obtaining effective wollastonite- and diopside-containing fillers for composite building materials. The high content of amorphous silicon dioxide in the obtained calcium and magnesium silicates enables to lower the temperature of their synthesis and to increase the industrial output of target wollastonite and diopside, and also to reduce the content of undesirable admixtures in their composition. The availability of large- tonnage alternative silicates can be seen as a sustainable alternative that brings ecological, technical and economic benefits to construction industry.
Hydrogen energy in Russia: Development forecasts
Authors: Minasyan Larisa , Blagin Anatoly , Kaneeva Anna , Leshcheva Olga , Popova Inna
Published: October 2024

The features of the Russian approach to the development of hydrogen energy with the aim of achieving the goal of carbon neutrality, designated by the United Nations, are considered. The advantages of the country's resource base have been identified, such as large reserves of natural gas, water sources, nuclear energy, as well as the existing infrastructure of production and supply chains. It is noted that in recent years there has been an attitude towards technological breakthroughs in this field based on the existing scientific groundwork and potential for further improvement of methods of production, storage and transportation of hydrogen. Government regulation and support for the development of this industry in partnership with the business community plays an important role. Pilot projects for the production of low-carbon and carbon- free hydrogen and ammonia were discussed, a number of which have already been commissioned. It is concluded that although 75% of newly commissioned capacities are green hydrogen production, trends towards reducing the carbon footprint of blue hydrogen persist. Both types have very noticeable negative manifestations, and in conditions of uncertainty it is still difficult to predict the priority of each of them.
Fast neutrons and gamma rays shielding properties for some nylon composite
Authors: Kareem Dawood Salwah , Ghali Ishnayyin Hadeel , Fadhil Mkhaiber Ahmed , Hatim Naseef Hadia
Published: October 2024

In this study, The removal parameters of macroscopic fast neutron cross-section, linear gamma ray attenuation, mean free path, and half-value layer (half-value thickness) were calculated for a polymer composite containing nylon 6 as a base material and starch powder, silica oxide, and calcium carbonate as reinforcement materials for different energies (0.05, 0.1, 0.3, 0.6, 0.8, 1, 3, 7, 10, 15) and for various concentrations (5, 10, 15, 20, 25). We used the x-com program to calculate gamma ray attenuation values. The results showed that the macroscopic cross-section of fast neutron attenuation and the linear attenuation coefficient for gamma rays increase with increasing reinforcement materials concentration, while the values of half-value layer decrease with increasing concentrations. When the energy increases, the half-value layer and the mean free path also increase, however, the values of the linear attenuation coefficient decrease.
Determination of tribotechnical properties of polymers depending on the test conditions
Authors: Biryukov Vladimir
Published: October 2024

The paper presents the results of morphological and tribotechnical tests of samples of ultrahigh molecular weight polyethylene (UHMWPE), high molecular weight polyethylene (HMWPE), polyethylene terephthalate (PET), polyoxymethylene (POM). Tribotechnical tests were carried out on a friction machine with a vertical axis of rotation of the spindle according to the scheme: “the end of the annular surface of the counter–flange sleeve (steel 40Kh, 48-52 HRC) is a plane (wide side of the polymer sample).” The moment of friction and the load on the samples were determined using strain gauges placed in the friction machine in continuous mode. The effect of the surface roughness of a 40Kh steel counter-tile on the friction coefficients when tested without lubricant and in the presence of hydraulic oil MGE-10A at a constant sliding speed has been established. The maximum values of the friction coefficients were obtained during friction without lubrication after processing the end face of the counter-tile with sandpaper P180 and P1200. The minimum values of the friction coefficients were obtained by lubricating MGE-10A after processing with sandpaper P1200 of a 40Kh steel counterplate. According to the morphology of the friction surfaces, the main wear mechanisms for UHMWPE, micro-cutting, HWMPE and PET, micro-cutting and plowing and for POM, fatigue wear and plowing are determined.
An approach to logical-mathematical computer modeling of linear and nonlinear dynamical systems
Authors: Zaytsev Anatoly , Kravchenko Vyacheslav , Shirapov Dashadondok
Published: October 2024

The paper deals with the problem of modeling linear and nonlinear dynamical systems using information technologies and programming. The processes of modeling, synthesis and inference of solutions to problems are considered, and the possibility of their integration within the described approach is shown. The substantive aspects of the development of special mathematical and algorithmic support for the construction of a software system for the analysis and processing of expert information for the purposes of automated synthesis and inference of solutions are briefly outlined. The aim of the work is to create a new approach of logical-mathematical computer modeling of linear and nonlinear dynamical systems and to develop a prototype of a software computational expert system based on it. As a result of the research, a universal approach of logical-mathematical computer modeling of linear and nonlinear dynamical systems has been developed and proposed. The proposed approach can be used to organize the process of computer modeling and automated synthesis of task solutions with the output of their results. The mathematical model of the knowledge base and process of its construction for the selected subject area, as well as the algorithm for outputting solutions to problems with its software implementation in the Python programming language, are shown. Examples of solution output for various linear and nonlinear problems are given. The developed prototype of the software computational expert system using the proposed logical- mathematical approach will significantly simplify the process of modeling dynamical systems and make the solution of problems' simpler and more understandable.
Partial discharges in power transformers
Authors: Lopatchenko Gleb , Groshev Alexander , Lukonin Alexey , Kuimov Denis , Yurov Alexander
Published: October 2024

Tansformers are among the most responsible and expensive elements of the power system, therefore monitoring the technical condition of the transformer is an important and urgent task. One of the signs of aging of insulation in a transformer may be partial discharges (PD), leading to its further failure. The use of monitoring systems based on PD analysis makes it possible to prevent the severe consequences of short circuits in transformers and, as a result, achieve significant economic effects during the operation of controlled high-voltage equipment. The transformer monitoring system based on the partial discharge method is complex and not always effective, because fixed discharges in transformer insulation can be observed for years and do not lead to breakdown, and among the PD it is not always possible to identify the leader's transition to the through phase in time, which creates sufficient conditions for breakdown. In practice, the discharge test is performed using chromatographic analysis of dissolved gases in oil (CADG) or by measuring discharge activity. The article analyzes the effectiveness of PD control methods and the need to develop mathematical models of partial discharges that allow studying the dynamics of the streamer-leader transition in controlled isolation.
Control systems with Thyristor converters
Authors: Alferov G. , Ivanov G. , Korolev V.
Published: October 2024

A system is considered, in the control loop of which there are thyristor converters or a special type of indirect control system. An example of constructing self-oscillations in a system describing the behavior of electrical devices using such elements in the control loop is given. Solutions for self-oscillations of a given period are constructed. Conditions for the existence of orbital asymptotic stability and Lyapunov stability for periodic solutions with a given period are presented, and a control loop is synthesized that ensures the existence of such solutions.
Characterisation of Nano Aluminium Oxide Filled Hybrid Cotton Glass FRP Composite Structures
Authors: Jyothula Sunil Kumar , K Chinna Maddaiah , GB Veeresh Kumar , Muhammed Anaz Khan
Published: October 2024

Natural fiber-based composite manufacturing is now an expanding field of study, and it is the preferred option not only because of its exceptional qualities such as light weight, rigidity, low density and superior mechanical properties, but also because it is affordable, biodegradable, fully or mostly recyclable and renewable. A Glass Fibre is a type of Reinforced Polymer (GFRP) made of tiny glass fibers embedded in a plastic matrix. Hybridization of natural and synthetic fibres has to be done to overcome the shortfall of these fibres. When compared to single Fibre Reinforced Polymer (FRP) composites, fibre-reinforced hybrid composites offer improved mechanical, thermal, and damping characteristics. The goal of this research is to see how Nano Aluminum Oxide (Al2O3) fillers affect the characteristics of hybrid cotton-glass FRP composites. The vacuum bagging technique was used to make nano Al2O3 particles - hybrid cotton-glass FRP composites out of glass fibre chopped strand mat, cotton fabric, epoxy resin, and nano-Al2O3 fillers. The nano Al2O3 fillers were integrated in different weight (wt.) ratios in the FRP and the effect on tensile, flexural and impact properties were examined.
Récepteurs des œstrogènes et vieillissement artériel
Authors: Marjollet Juline , Buscato Mélissa , Davezac Morgane , Vessieres Emilie , Gosset Anna , Adlanmerini Marine , Henrion Daniel , Lenfant Francoise , Arnal Jean-François , Fontaine Coralie
Published: October 2024

Les maladies cardiovasculaires (MCV) sont souvent perçues comme étant principalement masculines, alors qu’elles représentent la première cause de mortalité chez les femmes. Bien que les effets bénéfiques des œstrogènes soient bien établis chez les organismes jeunes, la question de savoir si les œstrogènes exogènes peuvent prolonger la protection contre les MCV après le début de la ménopause n’est toujours pas résolue. Cette revue décrit les études sur les effets des œstrogènes sur les artères, en mettant l’accent sur l’impact du vieillissement sur l’endothélium. Nous aborderons également l’impact de l’âge sur l’expression et la signalisation des récepteurs des œstrogènes (ER), avant d’exposer le progrès des connaissances sur les mécanismes d’action d’ERα afin d’optimiser le traitement hormonal de la ménopause.
Numerical modelling of hygro-mechanical behavior of Rhecktophyllum Camerunense vegatable fibers
Authors: Noutegomo Boris , Betene Ebanda Fabien , Atangana Ateba
Published: October 2024

Indeed the influence of humidity on the mechanical behavior of Rhecktophyllum Camerunense (RC) vegatable fiber was studied using numerical modelling and simulation. This method was used to investigate the hygromechanical caracteristics of the vegetable fiber that should be difficult to obtain experimentally. Another goal is to compare the results obtained experimentally and analytically in others works. The Finite Element Analysis using ANSYS sofware enables us to discretize a continuous problem and obtain an approximated solution. The Modeling Geometry adopted was an assembly of three concentric cylinders representing the sublayers S1, S2 and S3 of the fiber. The numerical model developed is a decoupled hygromechanical model. Thus the first stage of this model concerns the consideration of hygroscopy by simulating the diffusion of water within the material. Secondly, the mechanical calculation is carried out by taking as loading the results of the purely hygroscopic calculation, expressed in the form of hygroscopic fields. Identification of input parameters for the numerical simulation was found in literature. The results coroborated with the ones of literature and shown that humidity decrease the mechanical properties of RC vegetable fiber.
Association of Borderline Fetal Growth with Progression with Fetal Growth Restriction
Authors: Bronner Baillie A. , Holod Monique , Schermerhorn Margaret , Sung Juliana , Mccormick Anna C. , Reyes Samantha De Los
Published: October 2024

Objective This study aimed to evaluate if an estimated fetal weight (EFW) between 10 and 15th percentiles at the time of anatomy ultrasound, referred to as borderline fetal growth, is associated with progression to fetal growth restriction (FGR) on subsequent ultrasound, delivery of a small for gestational age (SGA) neonate, or neonatal intensive care (NICU) admission.

Study design We performed a secondary analysis using the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-be (nuMom2b) data. The exposures were normotensive pregnancies with non-anomalous singleton gestations with normal growth, defined as EFW >15th percentile at the anatomy scan compared to borderline fetal growth fetuses defined as those with an EFW in the 10 to 15th percentiles. The primary outcome was FGR at subsequent ultrasound, defined as EFW or AC <10%. The secondary outcomes were NICU admission and SGA neonate. Univariable analyses were performed comparing maternal baseline demographic and clinical characteristics. Multivariable analysis was performed for the primary outcome with variables adjusted a priori for body mass index, smoking status, race/ethnicity, insurance status, and drug use.

Results In total, 4,883 patients met inclusion criteria with 114 in the borderline fetal growth group and 4,769 in the normal growth group. There were no significant differences in maternal demographic or medical characteristics. In adjusted multivariable analysis, patients with borderline growth had significantly higher odds of being diagnosed with FGR at their subsequent scan (adjusted odds ratio [aOR] = 6.68, confidence interval [CI]: 3.98–11.20) compared to those with normal growth. For secondary outcomes, patients with borderline fetal growth were significantly more likely to have SGA neonates (6.14 vs. 2.67%, p = 0.025). There was no difference in admissions to the NICU between groups.

Conclusion Diagnosis of borderline fetal growth at the time of the anatomy scan was associated with significantly increased odds of progression to FGR at subsequent scans and delivery of an SGA neonate.

Key Points
Efficacy and safety of endoscopic ultrasonography-guided ethanol injections of small pancreatic neuroendocrine neoplasms: a prospective multicenter study
Authors: Matsumoto Kazuyuki , Kato Hironari , Itoi Takao , Kitano Masayuki , Hara Kazuo , Kuwatani Masaki , Takenaka Mamoru , Ashida Reiko , Mukai Shuntaro , Okuno Nozomi , Kawakubo Kazumichi , Yamazaki Tatsuhiro , Sakurai Jun , Nakatsuka Yuki , Yoshida Michihiro , Otsuka Motoyuki
Published: October 2024

Endoscopic ultrasonography (EUS)-guided ethanol injection (EI) has recently been introduced as one of the management strategies for pancreatic neuroendocrine neoplasms (PNENs); however, its role as a surgical alternative is unclear. We evaluated the efficacy and safety of EUS-EI in treating small PNENs through a prospective multicenter study.

Patients with grade 1 tumors of ≤15 mm confirmed by pathology were included. The primary end point assessed efficacy and safety, measuring complete ablation using computed tomography at 1 and 6 months, prevention of adverse events (AEs) within 1 month, severe pancreatic fistula at 1 month, and incidence/worsening of diabetes mellitus (DM) at 6 months. The composite end point of EUS-EI was compared with that of historical results of a study based on surgical treatment.

25 patients with PNENs, with a median tumor size of 10.1 mm, were treated using EUS-EI. The composite primary end point was achieved by 76.0% of patients (19/25; 95%CI 54.9%–90.6%), a proportion significantly higher than that of surgical treatment (P = 0.008). Regarding efficacy, 88.0% (22/25) of patients achieved complete ablation at 1 and 6 months (95%CI 68.8%–97.5%). Regarding safety, 96.0% (24/25) of patients had no severe AEs within 1 month (95%CI 79.7%–99.9%). No patients had severe pancreatic fistulas at 1 month, and 84.0% (21/25) had no incidence or exacerbation, or both, of DM at 6 months (95%CI 63.9%–95.5%).

EUS-EI is safe and could be a potent treatment option for patients with small PNENs.
Artificial intelligence for low income countries
Authors: Khan Muhammad Salar , Umer Hamza , Faruqe Farhana
Published: October 2024

The global adoption rate of artificial intelligence (AI) is rising, indicating its transformative potential. However, this adoption is far from uniform, with low-income countries (LICs) trailing behind significantly. Despite needing AI for development, LICs face multiple challenges in harnessing its benefits, exacerbating existing global disparities in technology adoption. In spite of the potentially important role that AI can play in the development of LICs, AI literature overlooks these countries, with research predominantly focused on more advanced economies. This lack of inclusivity contradicts the principles of distributive justice and global equity, prompting us to explore the importance of AI for LICs, offer a theoretical grounding for AI catch-up, identify effective AI domains, and propose strategies to bridge the AI gap. Drawing insights from the leapfrogging and absorptive capacities literature, our position paper presents the feasibility of AI catch-up in LICs. One crucial finding is that there is no one-size-fits-all approach to achieving AI catch-up. LICs with strong foundations could favor leapfrogging strategies, while those lacking such foundations might find learning and acquisition prescriptions from absorptive capacity literature more relevant. The article also makes policy recommendations that advocate for the swift integration of AI into critical LIC domains such as health, education, energy, and governance. While LICs must address challenges related to digital infrastructure, human capital, institutional robustness, and effective policymaking, among others, we believe that advanced AI economies and relevant international organizations like UNESCO, OECD, USAID, and the World Bank can support LICs in AI catch-up through tech transfer, grants, and assistance. Overall, our work envisions global AI use that effectively bridges development and innovation disparities.
Boundary algebras of the Kitaev quantum double model
Authors: Chuah Chian Yeong , Hungar Brett , Kawagoe Kyle , Penneys David , Tomba Mario , Wallick Daniel , Wei Shuqi
Published: October 2024

The recent article by Jones et al. [arXiv:2307.12552 (2023)] gave local topological order (LTO) axioms for a quantum spin system, showed they held in Kitaev’s Toric Code and in Levin-Wen string net models, and gave a bulk boundary correspondence to describe bulk excitations in terms of the boundary net of algebras. In this article, we prove the LTO axioms for Kitaev’s Quantum Double model for a finite group G. We identify the boundary nets of algebras with fusion categorical nets associated to (Hilb(G),C[G]) or (Rep(G),CG) depending on whether the boundary cut is rough or smooth, respectively. This allows us to make connections to the work of Ogata [Ann. Henri Poincaré 25, 2353–2387 (2024)] on the type of the cone von Neumann algebras in the algebraic quantum field theory approach to topological superselection sectors. We show that the boundary algebras can also be calculated from a trivial G-symmetry protected topological phase (G-SPT), and that the gauging map preserves the boundary algebras. Finally, we compute the boundary algebras for the (3 + 1)D Quantum Double model associated to an Abelian group.
Hole and electron spin lifetime in lightly n-doped silicon at low temperatures
Authors: Zucchetti C. , Scali F. , Ballabio A. , Bollani M. , Isella G. , Ferrari G. , Finazzi M. , Ciccacci F. , Bottegoni F.
Published: October 2024

We report on photoinduced inverse spin-Hall effect (ISHE) measurements as a function of the incident photon energy in the 4–50 K temperature range for a Pt/n-doped Si junction. Optical spin injection allows generating a spin-oriented population of electrons and holes around the Δ valleys and Γ point of the Si Brillouin zone, respectively. Spin-polarized carriers cross the Pt/Si contact and then enter the Pt overlayer, where spin-to-charge conversion occurs by means of spin-dependent scattering with Pt nuclei. For temperatures T up to 20 K, most of the dopants are not ionized, so that the electric field, stemming from the contact potential between Pt and Si, extends to the whole Si substrate, which becomes insulating, and only spin-oriented holes reach the Pt layer and contribute to the ISHE spectra. For T>20 K, donors are partially ionized, and the resulting space charge close to the Pt/Si interface leads to the formation of a Schottky contact where the electric field rapidly vanishes within a few micrometers. As a consequence, also spin-polarized electrons enter Pt by means of thermionic emission, contributing to the ISHE signal. We numerically solve the one-dimensional spin drift-diffusion equations for holes and electrons and estimate the temperature dependence of the spin lifetime in Si for both populations, demonstrating that Si may serve as a versatile platform for spintronic applications, able to leverage both electrons and holes.
Controllable and fast growth of high-quality atomically thin and atomically flat Bi2O2Se films
Authors: Feng Yusen , Chen Pei , Li Nian , Li Menglu , Liang Suzhe , Xu Minghui , Zhao Yan , Gong Jie , Zhang Shu , Leng Huaqian , Zhou Yuanyuan , Wang Yong , Xiao Haiyan , Zhang Ke , Qiao Liang
Published: October 2024

As a promising 2D material, bismuth oxyselenide (Bi2O2Se) has demonstrated significant potential to overcome existing technical barriers in various electronic device applications due to its unique physical properties like high symmetry, adjustable electronic structure, and ultra-high electron mobility. However, the rapid growth of Bi2O2Se films down to a few atomic layers with precise control remains a significant challenge. In this work, the growth of two-dimensional (2D) Bi2O2Se thin films by the pulsed laser deposition (PLD) method is systematically investigated. By controlling temperature, oxygen pressure, laser energy density, and laser emission frequency, we finally prepare atomically thin and flat Bi2O2Se (001) thin films on the (001) surface of SrTiO3. Importantly, we provide a fundamental and unique perspective toward understanding the growth process of atomically thin and flat Bi2O2Se films, and the growth process primarily proceeds in four steps. Moreover, the combined results of the crystallinity quality, surface morphology, and the chemical states demonstrate the PLD-growth of high-quality Bi2O2Se films in a controllable and fast mode.
Improvement of charge trapping memory performance by modulating band alignment with oxygen plasma
Authors: Chai Puhao , Zhu Jun , Li Kuangkuang , Chen Jiale
Published: October 2024

Metal-oxide charge trapping memory (CTM) integration into amorphous and organic flexible devices encounters challenges due to high-temperature treatment. Our approach enhances memory performance via room-temperature oxygen plasma treatment, subtly adjusting surface band alignment without changing the original material structure and surface roughness. Infiltration of oxygen plasma induces band alignment bending, creating a barrier for charge trapping. The device with oxygen plasma treatment exhibits an impressive 19.06 V memory window and a charge trapping density of 3.58 × 1013/cm2. In comparison, the memory window of untreated device only has 5.56 V, demonstrating that oxygen plasma treatment significantly improves memory characteristics. The charge retention rate exhibits outstanding stability, potentially reaching 94% after a decade. It should be noted that careful control during plasma treatment is crucial to maintaining optimal memory effects. This facile, efficient technique, applicable to various oxide layers, offers a way for future advancements in metal-oxide CTM technology.
Improved modularity and new features in ipie: Toward even larger AFQMC calculations on CPUs and GPUs at zero and finite temperatures
Authors: Jiang Tong , Baumgarten Moritz K. A. , Loos Pierre-François , Mahajan Ankit , Scemama Anthony , Ung Shu Fay , Zhang Jinghong , Malone Fionn D. , Lee Joonho
Published: October 2024

ipie is a Python-based auxiliary-field quantum Monte Carlo (AFQMC) package that has undergone substantial improvements since its initial release [Malone et al., J. Chem. Theory Comput. 19(1), 109–121 (2023)]. This paper outlines the improved modularity and new capabilities implemented in ipie. We highlight the ease of incorporating different trial and walker types and the seamless integration of ipie with external libraries. We enable distributed Hamiltonian simulations of large systems that otherwise would not fit on a single central processing unit node or graphics processing unit (GPU) card. This development enabled us to compute the interaction energy of a benzene dimer with 84 electrons and 1512 orbitals with multi-GPUs. Using CUDA and cupy for NVIDIA GPUs, ipie supports GPU-accelerated multi-slater determinant trial wavefunctions [Huang et al. arXiv:2406.08314 (2024)] to enable efficient and highly accurate simulations of large-scale systems. This allows for near-exact ground state energies of multi-reference clusters, [Cu2O2]2+ and [Fe2S2(SCH3)4]2−. We also describe implementations of free projection AFQMC, finite temperature AFQMC, AFQMC for electron–phonon systems, and automatic differentiation in AFQMC for calculating physical properties. These advancements position ipie as a leading platform for AFQMC research in quantum chemistry, facilitating more complex and ambitious computational method development and their applications.
Thermal transport and spin–phonon interaction in magnetic Janus Cr2X3S3 (X = Br, I) monolayers
Authors: Singh Rana Ajay Partap , Bera Chandan
Published: October 2024

Comprehending the relationship between spin and phonons is essential to regulate the lattice thermal conductivity in 2D magnetic materials. Lattice thermal conductivity is a relevant part to consider in magnetic data storage and the working of spin-based devices. In this article, we examined the origin and effect of spin–phonon coupling (SPC) on the lattice thermal conductivity of pristine CrI3 monolayer-based Janus monolayers Cr2X3S3 (X=Br,I). We find a high SPC in these Janus monolayers due to in-plane Cr–S atomic vibrations. We observe a reduction in the lattice thermal conductivity at Janus monolayer magnetic states (∼52.3% in Cr2Br3S3 and ∼63.9% in Cr2I3S3) compared to its paramagnetic states. The analysis is also conducted to determine which magnetic state has more anharmonicity using potential energy wells. A wide range of 2D magnetic materials can benefit from our results in the future development of spin-based thermal devices.
Electric-field-induced enhancement of exciton binding energy in one-dimensional phosphorene atomic chain
Authors: Huang Wenzhuo , Zhong Jun , Sheng Weidong
Published: October 2024

An electric field normally increases the separation between the electron and hole in an exciton without intrinsic polarization and suppresses their Coulombic interaction, resulting in the reduction of its binding energy. Our study of one-dimensional (1D) excitons in phosphorene atomic chains, by using the exact diagonalization method, however, reveals that an electric field applied along the chain axis actually increases the exciton binding energies. Further analysis shows that the electric field tends to enhance the long-range interaction between the electron and hole while suppressing their short-range interaction by inducing an alternating charge distribution along the atomic chain. The zigzag symmetry is believed to account for this unique excitonic phenomenon in the 1D system.
Application of artificial neural networking to scrutinize the three-dimensional stagnation-point flow with variable physical properties
Authors: Saleem Sana , Ul Haq Rizwan , Mustafa M. , Soomro F. A.
Published: October 2024

This work examines the steady three-dimensional stagnation point of an electrically conducting Newtonian fluid under Oberbeck–Boussinesq approximation. This article is concerned with the boundary-layer formation over the vertical sheet. An analysis has been carried out to investigate the influence of variable fluid properties in mixed convection three-dimensional flow of viscous fluid by a vertical surface with heat transfer. The mathematical model incorporates by considering temperature-dependent variations in viscosity and thermal conductivity. The governing equations are transformed into nonlinear partial differential equations by appropriate transformation and admit local-similar solutions. The flow has to satisfy ordinary differential equations whose solution depends upon different parameters such as mixed convection parameter λ and variable viscosity θr, and c1 shows 3-dimensional motion of flow. Quantitative analysis of the flow field and heat transfer characteristics is conducted using graphs and numerical values obtained through Bvp4c MATLAB. A novel approach using Artificial Neural Networks (ANNs) has been used to accurately predict heat transfer parameters. The ANN model is trained using a comprehensive dataset obtained from numerical simulations and experimental measurements. The inputs to the ANN include relevant flow parameters such as Reynolds number, Prandtl number, and geometrical characteristics, while the outputs are the corresponding skin friction and the Nusselt number. The results indicate that the ANN model exhibits excellent predictive accuracy compared to traditional empirical correlations and computational fluid dynamics simulations. The graphical representation of emergent parameters has been explored, along with a corresponding discussion. The comparison is being made between the effects of constant and variable fluid properties.
High-fidelity reconstruction of porous cathode microstructures from FIB-SEM data with deep learning
Authors: Sun Yujian , Pan Hongyi , Wang Bitong , Li Yu , Wang Xuelong , Li Jizhou , Yu Xiqian
Published: October 2024

Accurate modeling of lithium-ion battery (LIB) electrode microstructures provides essential references for understanding degradation mechanisms and optimizing materials. Traditional segmentation methods often struggle to accurately capture the complex microstructures of porous LIB electrodes in focused ion beam scanning electron microscopy (FIB-SEM) data. In this work, we develop a deep learning model based on the Swin Transformer to segment FIB-SEM data of a lithium cobalt oxide electrode, utilizing fused secondary and backscattered electron images. The proposed approach outperforms other deep learning methods, enabling the acquirement of 3D microstructure with reduced particle elongated artifacts. Analyses of the segmented microstructures reveal improved electrode tortuosity and pore connectivity crucial for ion and electron transport, emphasizing the necessity of accurate 3D modeling for reliable battery performance predictions. These results suggest a path toward voxel-level degradation analysis through more sensible battery simulation on high-fidelity microstructure models directly twinned from real porous electrodes.