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Detection of a Quasiperiodic Phenomenon of a Binary Star System Using Convolutional neural network

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Intelligent Automation & Soft Computing 2023年第9期37卷 2519-2535页

作者： Denis Benka Sabína Vasová michal Kebísek.maximilián Strémy Institute of Applied Informatics Automation and MechatronicsFaculty of Materials Science and TechnologySlovak University of TechnologyTrnava91724Slovakia

Pattern recognition algorithms are commonly utilized to discover certain patterns,particularly in image-based *** study focuses on quasiperiodic oscillations(QPO)in celestial objects referred to as cataclysmic variables(CV).We are dealing with interestingly indistinct QPO signals,which we analyze using a power density spectrum(PDS).The confidence in detecting the latter using certain statistical approaches may come out with less significance than the *** work with real and simulated QPO data of a CV called mV *** primary statistical tool for determining confidence levels is sigma *** aforementioned CV has scientifically proven QPO existence,but as indicated by our analysis,the QPO ended up falling below 1-σ,and such QPOs are not noteworthy based on the former *** intend to propose and ultimately train a convolutional neural network(CNN)using two types of QPO data with varying amounts of training dataset *** aim to demonstrate the accuracy and viability of the classification using a CNN in comparison to sigma *** resulting detection rate of our algorithm is very plausible,thus proving the effectiveness of CNNs in this scientific area.

关键词： Convolutional neural network quasi-periodic oscillation cataclysmic variable simulation

Fe-N-C catalysts for oxygen electroreduction under external magnetic fields:Reduction of magnetic O_(2) to nonmagnetic H_(2)O

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Journal of Energy Chemistry 2022年第1期31卷 296-308,I0008页

作者： Wojciech Kicinski Jakub P.sek.Agata Kowalczyk Sylwia Turczyniak-Surdacka Anna m.Nowicka Slawomir Dyjak Boguslaw Budner mikolaj Donten Institute of Chemistry Military University of Technology2 Kaliskiego Str.PL 00-908 WarsawPoland Faculty of Chemistry University of WarsawPasteura 1 StrPL 02-093 WarsawPoland Faculty of Chemistry Biological and Chemical Research CentreUniversity of WarsawZwirki i Wigury 101 StrPL 02-089 WarsawPoland Institute of Optoelectronics Military University of Technology.2 Kaliskiego StrPL 00-908 WarsawPoland

An extensive analysis of iron-nitrogen-carbon(Fe-N-C)electrocatalysts synthesis and activity is presented concerning synthesis conditions such as initial Fe content,pyrolysis temperature and atmosphere(inert N_(2),reducing NH_(3),oxidizing Cl_(2) and their sequential combinations)and the influence of an external magnetic field on their performance in oxygen reduction reaction(ORR).Thermosetting porous polymers doped with FeCl_(3) were utilized as the Fe-N-C catalysts *** pyrolysis temperature was varied within a 700-900℃*** temperature and atmosphere of pyrolysis strongly affect the porosity and compositi on of the resultant Fe-N-C catalysts,while the in itial amount of Fe precursor shows much weaker *** under NH_(3) yields materials similar to those pyrolyzed under an inert atmosphere(N_(2)).In contrast,pyrolysis under Cl_(2) yields carbon of peculiar character with highly disordered structure and extensive *** application of a static external magnetic field strongly enhances the ORR process(herein studied in an alkaline environment)and the enhancement correlates with the Fe content in the Fe-N-C *** Fe-N-C materials containing ferromagnetic iron phase embedded in N-doped microporous carbon constitute attractive catalysts for magnetic field-aided anion exchange membrane fuel cell technology.

关键词： Oxygen reduction reaction Fe-N-C catalyst PGm-free catalyst magnetic field Chronoamperometry Anion exchange membrane fuel cell (AEmFC)

Regeneration of neurotransmission transcriptome in a model of epileptic encephalopathy after antiinflammatory treatment

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neural Regeneration Research 2018年第10期13卷 1715-1718页

作者： Dumitru A.Iacobas Libor Velísek Center for Computational Systems Biology Prairie View AM University Prairie View TX USA D.P.Purpura Department of neuroscience Albert Einstein College of MedicineNew York NY USA Department of Cell Biology & Anatomy New York Medical CollegeValhalla NY USA Department of neurology New York Medical CollegeValhalla NY USA Department of Pediatrics New York Medical CollegeValhalla NY USA

Inflammation is an established etiopathogenesis factor of infantile spasms（IS）, a therapy-resistant epileptic syndrome of infancy. We investigated the IS-associated transcriptomic alterations of neurotransmission in rat hypothalamic arcuate nucleus, how they are corrected by antiinflamatory treatments and whether there are sex differences. IS was triggered by repeated intraperitoneal administration of N-methyl-D-aspartic acid following anti-inflammatory treatment（adreno-cortico-tropic-hormone（ACTH） or PmX53）or normal saline vehicle to prenatally exposed to betamethasone young rats. We found that treatments with both ACTH and PmX53 resulted in substantial recovery of the genomic fabrics of all types of synaptic transmission altered by IS. While ACTH represents the first line of treatment for IS, the even higher efficiency of PmX53（an antagonist of the complement C5 a receptor） in restoring the normal transcriptome was not expected. In addition to the childhood epilepsy, the recovery of the neurotransmission genomic fabrics by PmX53 also gives hope for the autism spectrum disorders that share a high comorbidity with IS. Our results revealed significant sex dichotomy in both IS-associated transcriptomic alterations（males more affected） and in the efficiency of PmX53 anti-inflammatory treatment（better for males）. Our data further suggest that anti-inflammatory treatments correcting alterations in the inflammatory transcriptome may become successful therapies for refractory epilepsies.

关键词： adreno-cortico-tropic-hormone autism cholinergic transmission hypothalamus infantile spasms microarrays PmX53 sex differences

Characterization of the High-Strength mg–3Nd–0.5Zn Alloy Prepared by Thermomechanical Processing

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Acta metallurgica Sinica(English Letters) 2019年第3期32卷 321-331页

作者： Ji■í Kub■sek.Drahomír Dvorsk■ Jozef Vesel■ Peter min■rik m■ria Zemkov■ Dalibor Vojtěch Department of metals and Corrosion Engineering Faculty of Chemical Technology University of Chemistry and Technology Prague Department of Physics of materials Charles University

magnesium alloys based on Nd and Zn are promising materials for both aviation industry and medical *** mechanical properties of these materials can be achieved by thermomechanical processing such as extrusion or rolling and by aging treatment, which can significantly strengthen the alloy. The question remains especially about the connection of texture strength created in the alloys based on the specific conditions of preparation. This work focuses on the mg–3 Nd–0.5 Zn magnesium alloy prepared by hot extrusion of the as-cast state at two different temperatures combined with heat pre-treatment. Extrusion ratio of 16 and rate of 0.2 mm/s at 350 and 400 °C were selected for material preparation. The structures of prepared materials were studied by scanning electron microscopy and transmission electron microscopy. The effect of microstructure on mechanical properties was evaluated. Obtained results revealed the strong effect of thermal pre-treatment on final microstructure and mechanical properties of extruded materials. The Hall–Petch relation between grain size and tensile yield strength has been suggested in this paper based on the literature review and presented data. The observed behavior strongly supports the fact that the Hall–Petch of extruded mg–3Nd–0.5 Zn alloys with different texture intensities cannot be clearly estimated and predicted. In addition, Hall–Petch relations presented in literature can be sufficiently obtained only for fraction of the mg–3Nd–0.5 Zn alloys.

关键词： mg–Nd–Zn alloys Extrusion Thermal treatment microstructure mechanical properties

The effect of powder size on the mechanical and corrosion properties and the ignition temperature of WE43 alloy prepared by spark plasma sintering

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Journal of magnesium and Alloys 2021年第4期9卷 1356-1369页

作者： Drahomír Dvorský JiríKubásek.michaela Roudnická Filip Pruša David necas Peter minárik Jitka Stráská Dalibor Vojtech University of Chemistry and Technology Faculty of Chemical TechnologyDepartment of Metals and Corrosion EngineeringTechnická516628 Praha 6–DejvicePragueCzech Republic Institute of Physics Czech Academy of ScienceNa Slovance 1999/218221 Praha 8PragueCzech Republic Department of Physics of materials Charles UniversityKe Karlovu 5Prague 12116Czech Republic

Powder metallurgy is a powerful method for the preparation of materials with superior *** work aimed to investigate the effect of powder size on the microstructure,mechanical,and corrosion properties of advanced WE43(mg-4Y-3REE-Zr)alloy prepared by spark plasma sintering(SPS).At the same time,the effect of HF pre-treatment of the powder on the properties of final compacted products is *** powder particles yielded microstructure with more interfaces formed by Y_(2)O_(3),or mgF_(2) and YF_(3).These interfaces work as barriers against corrosion,which greatly improves corrosion *** suggested pre-treatment of powder in HF further reduced the corrosion rate of the compacted *** the contrary,fragile interfaces of YF_(3) decreased mechanical properties as the crack primarily propagates through these *** original powder containing the mixture of all powder fractions exerted the best combination of mechanical *** size has also shown to affect ignition *** highest ignition temperature was measured for the finest powder fraction.

关键词： Powder metallurgy mechanical properties Corrosion Interface SPS

Two macrophages, osteoclasts and microglia: from development to pleiotropy

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Bone Research 2021年第2期9卷 143-152页

作者： Ji-Won Lee In-Hee Lee Tadahiro Iimura sek.Won Kong Department of nephrology Transplant Research ProgramBoston Children’s HospitalBostonMA 02115USA Department of Pharmacology Graduate School of Dental MedicineHokkaido UniversitySapporo 060-8586Japan Computational Health Informatics Program Boston Children’s HospitalBostonMA 02115USA Department of Pediatrics Harvard Medical SchoolBostonMA 02115USA

Tissue-resident macrophages are highly specialized to their tissue-specific microenvironments,activated by various inflammatory signals and modulated by genetic and environmental *** and microglia are distinct tissue-resident cells of the macrophage lineage in bone and brain that are responsible for pathological changes in osteoporosis and Alzheimer’s disease(AD),*** is more frequently observed in individuals with AD compared to the prevalence in general *** of AD is often delayed until underlying pathophysiological changes progress and cause irreversible damages in structure and function of *** such earlier diagnosis and intervention of individuals at higher risk would be indispensable to modify clinical *** is the phenomenon that a genetic variant affects multiple traits and the genetic correlation between two traits could suggest a shared molecular *** this review,we discuss that the Pyk2-mediated actin polymerization pathway in osteoclasts and microglia in bone and brain,respectively,is the horizontal pleiotropic mediator of shared risk factors for osteoporosis and AD.

关键词： diagnosis osteoporosis osteoclast

用于Friedel-Craft甲苯苯甲酰化反应的铟催化剂的多相化(英文)

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催化学报 2012年第11期33卷 1802-1808页

作者： Farook ADAm Kei Lin sek School of Chemical Sciences Universiti Sains MalaysiaPenang 11800Malaysia

Indium incorporated silica samples with different indium contents were synthesized using a template free sol-gel *** silica used was extracted from rice husk(RH) and the resulting catalyst was labeled as RH-xIn(x = 5%,10%,15%,and 20%).From the N2 adsorption analysis the presence of type IV isotherm in RH-blank and RH-xIn indicated the mesoporous nature of the *** the XRD pattern,a broad band at ca.2θ = 25° was observed for all the catalysts which showed them to be *** micrographs revealed that the material is composed of ***-Craft benzoylation of toluene was carried out using the RH-xIn *** optimum conditions for the benzoylation of toluene were determined and at 373 K,100% conversion and 89% selectivity for the para-product(i.e.4-methylbenzophenone) were obtained.

关键词： LFCO XRD 化学化学动力学

Superior Properties of mg–4Y–3RE–Zr Alloy Prepared by Powder metallurgy

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Journal of materials Science & Technology 2017年第7期33卷 652-660页

作者： Jirí Kubásek.Drahomír Dvorsky miroslav Cavojsky Dalibor Vojtěch Nad'a Beronská michaela Fousová Department of metals and Corrosion Engineering University of Chemistry and Technology PragueTechnická 5166 28 Prague 6Czech Republic Institute of materials and machine mechanics SAS Slovak Academy of SciencesDúbravskd cesta 9845 13 BratislavaSlovak Republic

magnesium alloys are important materials for application in the automotive and aviation industries. During the last few years, the number of possible applications as biodegradable implants in medicine has grown. mg-RE（rare earth） alloys belong to the most advanced group of products, offering the best combination of mechanical properties and corrosion resistance. Among these materials, WE43（mg-Y-Nd）is a very well-known commercial alloy that has been extensively studied for applications at increased temperatures and also in organisms. Although this material has been described, there are still possibilities to improve its properties and subsequently expand its applicability. Powder metallurgy has already been used for the preparation of magnesium alloys with superior mechanical properties and occasionally superior corrosion properties. Therefore, the present paper is oriented toward the preparation of mg-4Y-3RE-Zr（WE43） alloy by the powder metallurgy technique（WE43-Pm） and comparison of the final properties with the product of extrusion of as-cast ingot（WE43-Im）. Our processing leads to a partial improvement in the mechanical properties and superior corrosion resistance of WE43-Pm. The texture strength of WE43-Pm was low, and therefore, anisotropy of mechanical properties was suppressed.

关键词： magnesium alloys REEs(rare earth elements) Powder metallurgy mechanical properties Corrosion

Point-of-care ultrasound identification of pneumatosis intestinalis associated with Henoch-Schönlein purpura gastrointestinal involvement:A case report

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World Journal of Emergency medicine 2021年第1期12卷 76-78页

作者： sek.Wan Tan Vigil James Aswin Warier Gene Yong-kwang Ong Children’s Emergency KK Women’s and Children’s Hospital229899Singapore

Dear editor,Henoch-Schönlein purpura (HSP) is the commonestvasculitis in children, typically affecting children agedthree to ten years.[1] It is a multi-systemic vasculitismediated by type III hypersensitivity with deposition ofimmunoglobulin. An immune complex-mediated vasculitisaffects small vessels of the skin, joints, kidneys, andgastrointestinal (GI) tracts. HSP is usually a self-limitingcondition and resolves within six to eight weeks.[1]

关键词： gastrointestinal involvement Sch