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Synthetic and Systems Biotechnology 2022年第2期7卷 671-682页

作者： joshua c.corpuz Javier O.Sanlley Michael D.Burkart Department of chemistry and Biochemistry University of California-San Diego9500 Gilman DriveLa JollaCA92093-0358USA

Non-ribosomal peptide synthetases(NRPSs)are attractive targets for biosynthetic pathway engineering due to their modular architecture and the therapeutic relevance of their *** catalysis mediated by specific protein-protein interactions formed between the peptidyl carrier protein(PcP)and its partner enzymes,NRPS enzymology and control remains fertile ground for *** review focuses on the recent efforts within structural biology by compiling high-resolution structural data that shed light into the various protein-protein interfaces formed between the PcP and its partner enzymes,including the phosphopantetheinyl transferase(PPTase),adenylation(A)domain,condensation(c)domain,thioesterase(TE)domain and other tailoring enzymes within the *** our understanding of how the PcP recognizes partner proteins with the potential to use directed evolution and combinatorial biosynthetic methods will enhance future efforts in discovery and production of new bioactive compounds.

关键词： Natural products Protein-protein interactions Non-ribosomal peptide synthetase Peptidyl carrier protein combinatorial biosynthesis Synthetic biology

A system-on-chip microwave photonic processor solves dynamic RF interference in real time with picosecond latency

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Light(Science & Applications) 2024年第1期13卷 91-102页

作者： Weipeng Zhang joshua c.Lederman Thomas Ferreira de Lima Jiawei Zhang Simon Bilodeau Leila Hudson Alexander Tait Bhavin J.Shastri Paul R.Prucnal Department of Electrical and computer Engineering Princeton UniversityPrinceton08544NJUSA NEc Laboratories America Princeton08540NJUSA Department of Electrical and computer Engineering Queen’s UniversityKingstonK7L 3N6OntarioCanada Department of Physics Engineering Physics and AstronomyQueen’s UniversityKingstonK7L 3N6OntarioCanada

Radio-frequency interference is a growing concern as wireless technology advances,with potentially life-threatening consequences like interference between radar altimeters and 5 G cellular *** transceivers mix signals with varying ratios over time,posing challenges for conventional digital signal processing(DSP)due to its high *** challenges will worsen as future wireless technologies adopt higher carrier frequencies and data ***,conventional DSPs,already on the brink of their clock frequency limit,are expected to offer only marginal speed *** paper introduces a photonic processor to address dynamic interference through blind source separation(BSS).Our system-on-chip processor employs a fully integrated photonic signal pathway in the analogue domain,enabling rapid demixing of received mixtures and recovering the signal-of-interest in under 15 *** reduction in latency surpasses electronic counterparts by more than three orders of *** complement the photonic processor,electronic peripherals based on field-programmable gate array(FPGA)assess the effectiveness of demixing and continuously update demixing weights at a rate of up to 305 *** compact setup features precise dithering weight control,impedance-controlled circuit board and optical fibre packaging,suitable for handheld and mobile *** experimentally demonstrate the processor’s ability to suppress transmission errors and maintain signal-to-noise ratios in two scenarios,radar altimeters and mobile *** work pioneers the real-time adaptability of integrated silicon photonics,enabling online learning and weight adjustments,and showcasing practical operational applications for photonic processing.

关键词： processor mixing dynamic

The effect of Laves phases and nano-precipitates on the electrochemical corrosion resistance of Mg-Al-ca alloys under alkaline conditions

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Journal of Magnesium and Alloys 2024年第6期12卷 2447-2461页

作者： Markus Felten Veronika chaineux Siyuan Zhang Ali Tehranchi Tilmann Hickel christina Scheu joshua Spille Marta Lipińska-chwałek Joachim Mayer Benjamin Berkels Marcus Hans Imke Greving Silja Flenner Sandra Sefa Daniela Zander chair of corrosion and corrosion Protection RWTH Aachen UniversityAachen 52072 Germany Max-Planck-Institut für Eisenforschung GmbH Düsseldorf 40237 Germany central Facility for Electron Microscopy RWTH Aachen UniversityAachen 52074 Germany Ernst Ruska-centre for Microscopy and Spectroscopy with Electrons Forschungszentrum Jülich GmbHJülich 52428Germany Mathematical Image and Signal Processing Aachen Institute for Advanced Study in Computational Engineering ScienceRWTH Aachen UniversityAachen 52062 Germany Materials chemistry RWTH Aachen UniversityAachen 52074 Germany Institute of Materials Physics Helmholtz-Zentrum HereonGeesthacht 21502 Germany

The electrochemical corrosion mechanisms of Mg alloys were extensively studied in previous investigations of different chemical com-positions,modified surface states and various electrolyte ***,recent research focused on the active state of Mg dissolution,leading to unresolved effects of secondary phases adjacent to a stableα-solid solution passive *** present study investigates the fundamental electrochemical corrosion mechanisms of three different Laves phases with varying phase morphologies and phase fractions in the passive state of Mg-Al-ca *** microstructure was characterized by(transmission-)electron microscopy and synchrotron-based transmission X-ray *** electrochemical corrosion resistance was determined with a standard three-electrode setup and advanced in-situ flow cell measurements.A new electrochemical activity sequence(c15>c36>α-Mg>c14)was obtained,as a result of a stable passive layer formation on theα-solid ***,nm-scale Mg-rich precipitates were identified within the Laves phases,which tend to inhibit the corrosion kinetics.

关键词： Laves phase STEM Magnesium corrosion Passive layer

Dynamics of self-hybridized exciton–polaritons in 2D halide perovskites

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Light(Science & Applications) 2024年第1期13卷 13-22页

作者： Surendra B.Anantharaman Jason Lynch christopher E.Stevens christopher Munley chentao Li Jin Hou Hao Zhang Andrew Torma Thomas Darlington Francis coen Kevin Li Arka Majumdar PJames Schuck Aditya Mohite Hayk Harutyunyan joshua R.Hendrickson Deep Jariwala Department of Electrical and Systems Engineering University of PennsylvaniaPhiladelphiaPA19104USA KBR Inc. BeavercreekOH45431USA Air Force Research Laboratory Sensors DirectorateWright-Patterson Air Force BaseOH45433USA Department of Physics University of WashingtonSeattleWA98195USA Department of Physics Emory UniversityAtlantaGA30322USA Department of chemical and Biomolecular Engineering Rice UniversityHoustonTX77005USA Department of Materials Science and Nanoengineering Rice UniversityHoustonTX77005USA Applied Physics Program Smalley‐Curl InstituteRice UniversityHoustonTX77005USA Department of Mechanical Engineering Columbia UniversityNew YorkNY10027USA Department of Electrical and computer Engineering University of WashingtonSeattleWA98195USA

Excitons,bound electron–hole pairs,in two-dimensional hybrid organic inorganic perovskites(2D HOIPs)are capable of forming hybrid light-matter states known as exciton-polaritons(E–Ps)when the excitonic medium is confined in an optical *** the case of 2D HOIPs,they can self-hybridize into E–Ps at specific thicknesses of the HOIP crystals that form a resonant optical cavity with the ***,the fundamental properties of these self-hybridized E–Ps in 2D HOIPs,including their role in ultrafast energy and/or charge transfer at interfaces,remain ***,we demonstrate that>0.5µm thick 2D HOIP crystals on Au substrates are capable of supporting multiple-orders of self-hybridized E–P *** E–Ps have high Q factors(>100)and modulate the optical dispersion for the crystal to enhance sub-gap absorption and *** varying excitation energy and ultrafast measurements,we also confirm energy transfer from higher energy E–Ps to lower energy E–***,we also demonstrate that E–Ps are capable of charge transport and transfer at *** findings provide new insights into charge and energy transfer in E–Ps opening new opportunities towards their manipulation for polaritonic devices.

关键词： charge polar excitation

Synergistic Interactions of Soil and Vegetation in Agroforestry Systems in Mitigating climate change in Upper East Region, Ghana

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American Journal of climate change 2024年第2期13卷 140-162页

作者： joshua A. Adombire Abdul-Wahab M. Imoro Eunice Essel Nang B. Douti Department of Environmental Science C. K. Tedam University of Technology and Applied Sciences Navrongo Ghana Department of Forestry and Forest Resources Management University for Development Studies Tamale Ghana Department of crop Science and Biotechnology C. K. Tedam University of Technology and Applied Sciences Navrongo Ghana

climate change has been a global pandemic with its adverse impacts affecting environments and livelihoods. This has been largely attributed to anthropogenic activities which generate large amounts of Green House Gases (GHGs), notably carbon dioxide (cO2), methane (cH4), and nitrous oxide (N2O) among others. In the Upper East of Ghana, climate change manifests in erratic rainfalls, drought, high temperatures, high wind speeds, high intensity rainfall, windstorms, flooding, declining vegetation cover, perennial devastating bushfires etc. Practices such as burning farm residues, use of dung as fuel for cooking, excessive application of nitrogenous fertilizers, and deforestation that are prevalent in the region exacerbate the situation. Although, efforts made by governmental and none-governmental organizations to mitigate climate change through afforestation, agroforestry and promotion of less fuelwood consuming cook stoves, land management practices antagonize these efforts as more cO2 is generated than the carrying capacity of vegetation in the region. Research findings have established the role of trees and soil in carbon sequestration in mitigating climate. However, there is limited knowledge on how the vegetation and soil in agroforestry interplay in mitigation climate change. It is against this background that this review seeks to investigate how vegetation and soil in an agroforestry interact synergistically to sequester carbon and contribute to mitigating climate change in Upper East region of Ghana. In this review, it was discovered soil stored more carbon than vegetation in an agroforestry system and is much effective in mitigating climate change. It was found out that in order to make soil and vegetation in an agroforestry system interact synergistically to effectively mitigate climate change, climate Smart Agriculture practice which integrates trees, and perennials crops effectively mitigates climate. The review concluded that tillage practices that ensure r

关键词： climate change carbon Sequestration Agroforestry Photosynthesis Nutrient Mining Synergistic

Prevalence and Demographic Distributions of Pre-Eclampsia among Pregnant Women at Ho Teaching Hospital

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Open Journal of Obstetrics and Gynecology 2024年第4期14卷 621-636页

作者： Adwoa Nyarko joshua A. Kunfah David Z. Kolbilla collins Adombire Akayuure Jamilatu B. Kappiah Sylvanus Kampo Department of Physician Assistantship School of Medicine University of Health and Allied Sciences Ho Ghana Department of Anaesthesia Wa Regional Hospital Wa Ghana Department of Obstetrics and Gynecology School of Medicine University for Development Studies Tamale Ghana Department of Nursing School of Nursing and Midwifery C. K. Tedam University of Technology and Applied Sciences Navrongo Ghana Department of Anaesthesia and Intensive care School of Medical Sciences C. K. Tedam University of Technology and Applied Sciences Navrongo Ghana

Background: In Sub-Saharan Africa, pre-eclampsia remains a major health problem contributing to high rates of maternal mortality. Despite this condition having adverse effects on maternal and child health, its prevalence and associated risk factors are still significant, especially in developing countries including Ghana. This study aimed to assess the prevalence and demographic distributions associated with pre-eclampsia among pregnant women at the Ho Teaching Hospital. Methods: A facility-based retrospective study was conducted by reviewing available data or hospital records of pregnant mothers admitted to the labor and maternity wards from January 2018 to December 2020. All pregnant women who were diagnosed with pre-eclampsia within this period were included in the study. The data were collected using a structured checklist. Results: 5609 data on pregnant women from 2018 to 2020 were recorded. Out of the 5609 data recorded, 314 pre-eclampsia cases were recorded giving an overall prevalence of 5.6%. The yearly prevalence for 2018, 2019, and 2020 were 4.6%, 5.6%, and 6.6%, respectively. The most recorded pre-eclampsia cases were seen among women within the age group of 18 - 24 years. The data showed that 112 (35.7%) of the pregnant women who had pre-eclampsia were nulliparous. Pre-eclampsia-associated maternal and fetal complications were;preterm delivery 221 (70.4%), intrauterine fetal death 62 (19.7%), eclampsia 9 (2.9%), HELLP syndrome 5 (1.6%) and maternal death 17 (5.4%). Associated factors of pre-eclampsia were parity, level of education, and occupation (p ≤ 0.05). conclusion: The findings of this study showed a rising trend in the incidence of pre-eclampsia over the years at the Ho Teaching Hospital. Parity, level of education, and occupation were found to be associated with developing pre-eclampsia.

关键词： Pre-Eclampsia Prevalence Demographic Distributions Risk Factors Antenatal Maternal

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何谓新唯物主义:通向操演性新唯物主义

世界哲学 2024年第2期 33-45页

作者： [美]c.甘布 [美]J.哈南 [美]T.奈尔牛小雪(译) 华盛顿大学传播系丹佛大学传播系丹佛大学哲学系复旦大学哲学学院

当代西方新唯物主义的共识在于质疑人类中心主义预设,并要求恢复物质自身的活力。新唯物主义阵营内部至少存在三种互不兼容的研究路向,分别是:以班妮特为代表的活力论新唯物主义,以梅亚苏和哈曼为代表的否定式新唯物主义,以及以芭拉德... 详细信息

当代西方新唯物主义的共识在于质疑人类中心主义预设,并要求恢复物质自身的活力。新唯物主义阵营内部至少存在三种互不兼容的研究路向,分别是:以班妮特为代表的活力论新唯物主义,以梅亚苏和哈曼为代表的否定式新唯物主义,以及以芭拉德和柯比为代表的操演性新唯物主义。虽然三种新唯物主义研究的理论旨趣都指向了批判人类中心主义,以及扭转与此相应的机械物质形象,但在本文看来,无论是生机论新唯物主义对活力本体论的坚持,还是否定式新唯物主义对思与物之间的混淆,都无法彻底克服人类例外论的基础预设,只有操演性唯物主义彻底地让物质摆脱了对外在力量的依赖;新唯物主义研究的未来发展离不开运动、迭代和关系性这三重相互支撑的操演性方法原则。

关键词：生机论新唯物主义否定式新唯物主义操演性思辨实在论面向对象的本体论

First-Principles Investigation of charge Transfer Mechanism of B-Doped 3c-Sic Semiconductor Material

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World Journal of condensed Matter Physics 2024年第2期14卷 35-44页

作者： Abdullahi Alkali Dauda Muhammad Yusuf Onimisi Adeyemi joshua Owolabi Hameed Adeneyi Lawal Hassan Muhammad Gambo Bashir Mohammed Aliyu Surajo Bala Muhammad Lamido Madugu Muhammad Abdurrahman Nainna Johnson Akinade Bamikole Physics Department Faculty of Science Air Force Institute of Technology Kaduna Nigeria Physics Department Faculty of Science Nigeria Defence Academy Kaduna Nigeria Physics Department Umaru Musa Yar&#8217adua University Batagarawa Nigeria Physics Department Faculty of Science Gombe State University Gombe Nigeria Physics Department Federal University of Lafia Lafia Nigeria

This study delves into the charge transfer mechanism of boron (B)-doped 3c-Sic through first-principles investigations. We explore the effects of B doping on the electronic properties of 3c-Sic, focusing on a 12.5% impurity concentration. Our comprehensive analysis encompasses structural properties, electronic band structures, and charge density distributions. The optimized lattice constant and band gap energy of 3c-Sic were found to be 4.373 Å and 1.36 eV respectively, which is in agreement with previous research (Bui, 2012;Muchiri et al., 2018). Our results show that B doping narrows the band gap, enhances electrical conductivity, and influences charge transfer interactions. The charge density analysis reveals substantial interactions between B dopants and surrounding carbon atoms. This work not only enhances our understanding of the material’s electronic properties, but also highlights the importance of charge density analysis for characterizing charge transfer mechanisms and their implications in the 3c-Sic semiconductors.

关键词： First-Principles calculations DFT Boron (B)-Doped 3c-Sic charge Transfer

A New Artificial Neural Network Method for Solving Schrodinger Equations on Unbounded Domains

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communications in computational Physics 2022年第9期32卷 1039-1060页

作者： joshua P.Wilson Weizhong Dai Aniruddha Bora Jacob c.Boyt Mathematics and Statistics College of Engineering and ScienceLouisiana Tech UniversityRustonLA 71272USA Division of Applied Mathematics Brown UniversityProvidenceRI 02906USA

The simulation for particle or soliton propagation based on linear or nonlinear Schrodinger equations on unbounded domains requires the computational domain to be bounded,and therefore,a special boundary treatment such as an absorbing boundary condition(ABc)or a perfectly matched layer(PML)is needed so that the reflections of outgoing waves at the boundary can be minimized in order to prevent the destruction of the *** article presents a new artificial neural network(ANN)method for solving linear and nonlinear Schrodinger equations on unbounded *** particular,this method randomly selects training points only from the bounded computational space-time domain,and the loss function involves only the initial condition and the Schrodinger equation itself in the computational domainwithout any boundary ***,unlike standard ANNmethods that calculate gradients using expensive automatic differentiation,this method uses accurate finitedifference approximations for the physical gradients in the Schrodinger *** addition,a Metropolis-Hastings algorithm is implemented for preferentially selecting regions of high loss in the computational domain allowing for the use of fewer training points in each *** such,the present training method uses fewer training points and less computation time for convergence of the loss function as compared with the standard ANN *** new ANN method is illustrated using three examples.

关键词： Linear and nonlinear Schrodinger equations artificial neural network method convergence soliton and particle propagations

Initial assessment of imports of chlorinated paraffins into Nigeria and the need of improvement of the Stockholm and Rotterdam conventions

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Emerging contaminants 2022年第1期8卷 360-370页

作者： joshua O.Babayemi Innocent c.Nnorom Roland Weber Environmental Management and Toxicology Department of Biological SciencesUniversity of Medical Sciences OndoNigeria Anchor University centre for Global Health Nigeria Department of Pure and Industrial chemistry Abia State University UturuNigeria POPs Environmental consulting 73527Schw€abisch GmündGermany

Short-chain and medium-chain chlorinated paraffins(SccPs/MccPs)are of concern due to their persistence,bioaccumulation,and *** were listed in 2017 as persistent organic pollutants(POPs)in the Stockholm convention and Rotterdam convention for Prior Informed consent(PIc)*** are evaluated in the POPs Reviewing committee for *** in Africa demonstrate high SccP/MccP levels in house dust and human ***,this study undertook an initial assessment of the production and import situation in *** Nigerian government has not assessed SccPs yet and has no registered exemptions for SccPs and therefore should not produce or use ***,Nigeria has not notified Rotterdam convention of PIc procedure and,therefore,no SccP should be imported into *** no local production of SccPs/MccPs was observed in Nigeria,this study therefore compiled data on importation of SccPs/MccPs and products which may likely contain these chemicals from the UN comtrade Database for the period 1996 to *** the listing of SccPs in the Rotterdam convention,there is still no specific Harmonized System(HS)codes for SccPs/*** study therefore used HS codes of product categories known to contain SccPs/*** substance categories under which SccP/MccPs are usually imported include plasticisers and other product categories that amounted to 229,779 and 518,342 tonnes respectively but without specific information on the type of *** 39%of PVc and rubber imports of 2,683,015 tonnes and 3,516,052 tonnes respectively contain *** on the SccP and MccP impact factors from literature for china,the highest amount of SccP(33,712 tonnes)was imported in the different PVc products while rubber products accounted to 1386 tonnes and PUR foam to 2331 *** amount of imported MccPs in PVc products(25,599 tonnes)and rubber products(32,317 tonnes)was in the same order of magnitude while MccP imported in PUR foam was estimated

关键词： SccPs/MccPs Plasticisers Importation PVc HS code Inventory Nigeria