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Steroidal scaffold decorations in Solanum alkaloid biosynthesis

Molecular Plant 2024年第8期17卷 1236-1254页

作者： Rosalind Lucier Mohamed o.Kamileen Yoko Nakamura Sofiia Serediuk Ranjit Barbole Jens Wurlitzer Maritta Kunert Sarah Heinicke Sarah E.o'Connor Prashant D.Sonawane Department of Natural Product Biosynthesis Max Planck Institute for Chemical Ecology07745 JenaGermany Research Group Biosynthesis and NMR Max Planck Institute for Chemical Ecology07745 JenaGermany Biochemical Sciences Division CSIR-National Chemical LaboratoryPune 411008MaharashtraIndia

Steroidal glycoalkaloids(SGAs)are specialized metabolites produced by hundreds of Solanum species,including important vegetable crops such as tomato,potato,and *** it has been known that SGAs play important roles in defense in plants and“anti-nutritional"effects(e.g.,toxicity and bitterness)to humans,many of these molecules have documented anti-cancer,anti-microbial,antiinflammatory,anti-viral,and anti-pyretic *** these,α-solasonine andα-solamargine isolated from black nightshade(Solanum nigrum)are reported to have potent anti-tumor,anti-proliferative,and anti-inflammatory ***,α-solasonine andα-solamargine,along with the core steroidal aglycone solasodine,are the most widespread SGAs produced among the Solanum ***,it is still unknown how plants synthesize these bioactive steroidal *** comparative metabolomictranscriptome-guided approach,biosynthetic logic,combinatorial expression in Nicotiana benthamiana,and functional recombinant enzyme assays,here we report the discovery of 12 enzymes from *** that converts the starting cholesterol precursorto solasodine aglycone,and the downstreamα-solasonine,α-solamargine,and malonyl-solamargine SGA *** further identified six enzymes from cultivated eggplant that catalyze the production ofα-solasonine,α-solamargine,and malonyl-solamargine SGAs from solasodine aglycone via glycosylation and atypical malonylation *** work provides the gene tool box and platform for engineering the production of high-value,steroidal bioactive molecules inheterologoushosts usingsyntheticbiology.

关键词： steroidal glycoalkaloids Solanum biosynthetic pathway α-solamargine malonyl-solamargine specialized metabolites

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Physico−mathematical model of the voltage−current characteristics of light-emitting diodes with quantum wells based on the Sah−Noyce−Shockley recombination mechanism

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Journal of Semiconductors 2024年第8期45卷 25-33页

作者： Fedor I.Manyakhin Dmitry o.Varlamov Vladimir P.Krylov Lyudmila o.Morketsova Arkady A.Skvortsov Vladimir K.Nikolaev Dinamics Strength of Machines and Resisance of MaterialsMoscow Polytechnic UniversityRussia Biomedical and Electronic Means and Technologies Vladimir State UniversityRussia Computer-Aided Design and Engineering National University of Science and Technology"MISiS"Russia

Herein,a physical and mathematical model of the voltage−current characteristics of a p−n heterostructure with quantum wells(QWs)is prepared using the Sah−Noyce−Shockley(SNS)recombination mechanism to show the SNS recombination rate of the correction function of the distribution of QWs in the space charge region of diode configuration.A comparison of the model voltage−current characteristics(VCCs)with the experimental ones reveals their *** technological parameters of the structure of the VCC model are determined experimentally using a nondestructive capacitive approach for determining the impurity distribution profile in the active region of the diode structure with a profile depth resolution of up to 10Å.The correction function in the expression of the recombination rate shows the possibility of determining the derivative of the VCCs of structures with QWs with a nonideality factor of up to 4.

关键词： light-emitting diodes with quantum wells voltage−current relation nonideality factor recombination mechanism Sah−Noyce−Shockley model

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High-precision inverse potentials for neutron-proton scattering using piece-wise smooth Morse functions

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Chinese Physics C 2024年第10期48卷 201-213页

作者： Ayushi Awasthi Arushi Sharma Ishwar Kant o.S.K.S.Sastri Department of Physics and Astronomical Science Central University of Himachal PradeshDharmshala176215India

The aim of this study is to construct inverse potentials for various ℓ-channels of neutron-proton scattering using a piece-wise smooth Morse function as a *** phase equations for single-channel states and the coupled equations of multi-channel scattering are solved numerically using the 5^(th) order Runge-kutta *** employ a piece-wise smooth reference potential comprising three Morse functions as the initial *** a machine learning-based genetic algorithm,we optimize the model parameters to minimize the mean-squared error between simulated and anticipated phase *** approach yields inverse potentials for both single and multichannel scattering,achieving convergence to a mean-squared error≤10^(-3).The resulting scattering lengths"a_(0)"and effective ranges"r"for ^(3)S_(1) and ^(1)S_(0) states,expressed as[a_(0),r],are found to be[5.445(5.424),1.770(1.760)]and[–23.741(–23.749),2.63(2.81)],respectively;these values are in excellent agreement with experimental ***,the calculated total scattering cross-sections are highly consistent with their experimental counterparts,having a percentage error of less than 1%.This computational approach can be easily extended to obtain interaction potentials for charged particle scattering.

关键词： inverse potentials neutron-proton scattering piece-wise smooth Morse function phase function method reference potential approach genetic algorithm

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Tri-axial accelerometry allows to determine parental food provisioning behaviour in a marine bird

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Avian Research 2024年第3期15卷 345-351页

作者： Monserrat Del Caño Flavio Quintana Giacomo Dell’omo Agustina Gómez-Laich Instituto de Biología de organismos Marinos(IBIoMAR) CONICETBoulevard Brown 2915U9120ACDPuerto MadrynChubutArgentina ornis Italica Piazza Crati 1500199RomeItaly Departamento de Ecología Genética y Evolución(EGE)and Instituto de EcologíaGenética y Evolución de Buenos Aires(IEGEBA)CONICETFacultad de CienciasExactas y NaturalesUniversidad de Buenos AiresPabellón II Ciudad UniversitariaC1428EGACiudad Autónoma de Buenos AiresArgentina

The study of parental food provisioning is essential for understanding the breeding ecology of *** conducted the first study using accelerometry to detect food provisioning in birds,using Support Vector Machine(SVM)models to identify when adults feed chicks of three different age *** were attached to the head of adult female Imperial Shags(Leucocarbo atriceps),and various attributes derived from the acceleration signals were used to train SVM models for each chick age *** performance improved with chick age class,with SVM models achieving high overall accuracy(>88%)and highest sensitivity in older chick categories(>91%).However,precision values,especially for younger chicks,remained relatively low(between 26%and 45%).The application of a time filter based on the minimum duration of the observed food provisioning behaviours for each chick age category,improved model performance by reducing false provisioning behaviours,particularly in the model for older chicks,which showed the highest precision(72.4%).This study highlights the effectiveness of accelerometry and machine learning in studying parental food provisioning in birds,providing a rapid and accurate data collection method to complement traditional *** described methodology can be applied to any bird species that exhibits distinctive movements while feeding its offspring and has suitable characteristics for attaching an accelerometer to the body part that best captures this ***,it is hoped that the results of this study will contribute to future research on key questions in parental investment theory and reproductive strategies in birds.

关键词： Accelerometry Food provisioning Imperial shag Leucocarbo atriceps Seabird Support vector machine

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Development of bismuth-based solutions for well plugging and abandonment:A review

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Petroleum Research 2024年第2期9卷 250-264页

作者： Lewaa Hmadeh Marcelo Anunciação Jaculli Behzad Elahifar Sigbjørn Sangesland Norwegian University of Science and Technology PTSValgrindaS.P.Andersens veg 15 ANorway

Plugging and abandonment(P&A)is a crucial step of the well life *** of how long one stretches the productive life of a well,P&A operations will have to be carried out *** current panorama of our industry includes many wells to be plugged and abandoned,with steep requirements to abide by both regulations and societal *** this context,we must guarantee that no leakage occurs with an eternal perspective in *** has been the prime material for this task,but recent studies have indicated the potential of degradation over time-especially in corrosive environments-and the creation of leaking paths due to its *** has opened up a path toward the usage of alternative *** of the emerging candidates is bismuth,a metal with the unique characteristic of expanding when *** a trait could improve the overall sealability of wellbores and especially during P&*** article discusses the current status of bismuth sealing technologies,introducing the basics of bismuth,the ongoing efforts to qualify it as a barrier material,its potential applications,and the challenges that still need to be *** latest research indicates promising results in terms of its usage as a barrier element.

关键词： Bismuth plugs Bismuth-tin alloys Well plugging and abandonment Well integrity

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Music as medicine for traumatic brain injury:a perspective on future research directions

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Neural Regeneration Research 2024年第10期19卷 2105-2106页

作者： Anthony E.Kline Eleni H.Moschonas Corina o.Bondi Department of Physical Medicine&Rehabilitation University of PittsburghPittsburghPAUSA Safar Center for Resuscitation Research University of PittsburghPittsburghPAUSA Center for Neuroscience University of PittsburghPittsburghPAUSA Department of Critical Care Medicine University of PittsburghPittsburghPAUSA Center for the Neural Basis of Cognition University of PittsburghPittsburghPAUSA Department of Psychology University of PittsburghPittsburghPAUSA Department of Neurobiology University of PittsburghPittsburghPAUSA

Traumatic brain injury(TBI) impacts 69 million individuals globally each year and is a leading cause of death and disability(Dewan et al.,2019).The majority of moderate-to-severe TBI survivors endure long-lasting disturbances in motor,cognitive,and affect that negatively impacts their *** a plethora of research on pharmacological interventions for TBI has been conducted,none has translated to the clinic,thus advocating for the evaluation of nonpharmacological therapeutic approaches that may increase translational success.

关键词： injury traumatic

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Myelin histology:a key tool in nervous system research

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Neural Regeneration Research 2024年第2期19卷 277-281页

作者： Óscar Darío García-García Víctor Carriel Jesús Chato-Astrain Department of Histology Tissue Engineering GroupUniversity of Granada&Instituto de Investigación Biosanitaria ibs.GRANADAGranadaSpain

The myelin sheath is a lipoprotein-rich,multilayered structure capable of increasing conduction velocity in central and peripheral myelinated nerve *** to the complex structure and composition of myelin,various histological techniques have been developed over the centuries to evaluate myelin under normal,pathological or experimental ***,methods to assess myelin integrity or content are key tools in both clinical diagnosis and neuroscience *** this review,we provide an updated summary of the composition and structure of the myelin sheath and discuss some histological procedures,from tissue fixation and processing techniques to the most used and practical myelin histological staining *** the lipoprotein nature of myelin,the main features and technical details of the different available methods that can be used to evaluate the lipid or protein components of myelin are described,as well as the precise ultrastructural techniques.

关键词： fluorescence microscopy histology light microscopy lipid histochemistry metallographic techniques myelin histochemistry myelin immunohistochemistry myelin structure&composition myelin ultrastructural evaluation tissue fixation&processing

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Determination of critical state line(CSL)for silty-sandy iron ore tailings subjected to low-high confining pressures

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1684-1695页

作者： Nilo Cesar Consoli João Vítor de Azambuja Carvalho Alexia Cindy Wagner Hugo Carlos Scheuermann Filho Inácio Carvalho Pedro Pazzoto Cacciari João Paulo de Sousa Silva Civil Engineering Universidade Federal do Rio Grande do SulPorto AlegreRS90035-190Brazil Exploration and Mineral Projects-Mineral Development Centre VALE S.A.Santa LuziaMG33040-900Brazil Department of Civil Geological and Mining EngineeringPolytechnique MontrealQuebecH3C 3A7Canada

The disposal of filtered tailings in high dry stacks can induce particle breakage,changing the material's behaviour during the structure's *** grading changes influence material properties at the critical state,and this is not mature for intermediate artificial soils(tailings)in a broad range of confining *** this paper,it aims to describe the behaviour of iron ore tailings in a spectrum of confining pressures broader than the reported in previous studies.A series of consolidated drained(CD)triaxial tests was carried out with confining pressures ranging from 0.075 MPa to 120 *** results show that the amount of breakage plays an essential role in the response of iron ore *** existence of curved critical state line(CSL)in both specific volume(ν)-logarithm of mean effective stress(p′)and deviatoric stress(q)-mean effective stress(p′)planes,and different responses in the deviatoric stress-axial strain-volumetric strain curves were *** inverse S-shaped equation was proposed to represent the silty-sandy tailings'behaviour up to high pressures onν-lnp′*** proposed equation provides a basis for enhancing constitutive models and considers the evolution of the grading up to severe loading *** adjustment considered three regions with different responses associated with particle breakage at different pressure levels.

关键词： Tailings Iron ore tailings dry stacking Silty-sandy material Critical state soil mechanics High confining pressures Particle breakage

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3D printing of poly(ethyleneimine)-functionalized Mg-Al mixed metal oxide monoliths for direct air capture of Co_(2)

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Journal of Energy Chemistry 2024年第9期96卷 491-500页

作者： Qingyang Shao Zhuozhen Gan Bingyao Ge Xuyi Liu Chunping Chen Dermot o’Hare Xuancan Zhu Research Center of Solar Power&Refrigeration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Chemistry Research Laboratory Department of ChemistryUniversity of OxfordOxford OX13TAUK

Direct air capture(DAC)of Co_(2)plays an indispensable role in achieving carbon-neutral goals as one of the key negative emission *** large air flows are required to capture the ultradilute Co_(2)from the air,lab-synthesized adsorbents in powder form may cause unacceptable gas pressure drops and poor heat and mass transfer efficiencies.A structured adsorbent is essential for the implementation of gas-solid contactors for cost-and energy-efficient DAC *** this study,efficient adsorbent poly(ethyleneimine)(PEI)-functionalized Mg-Al-Co_(3)layered double hydroxide(LDH)-derived mixed metal oxides(MMos)are three-dimensional(3D)printed into monoliths for the first time with more than 90%adsorbent *** printing process has been optimized by initially printing the LDH powder into monoliths followed by calcination into MMo *** structure exhibits a 32.7%higher specific surface area and a 46.1%higher pore volume,as compared to the direct printing of the MMo powder into a *** impregnation of PEI,the monolith demonstrates a large adsorption capacity(1.82 mmol/g)and fast kinetics(0.7 mmol/g/h)using a Co_(2)feed gas at 400 ppm at 25℃,one of the highest values among the shaped DAC *** of the amino-polymers during the post-printing process affects the diffusion of Co_(2),resulting in slower adsorption kinetics of pre-impregnation monoliths compared to post-impregnation *** optimal PEI/MeoH ratio for the post-impregnation solution prevents pores clogging that would affect both adsorption capacity and kinetics.

关键词： 3D printing Mixed metal oxides Amine functionalization Structured adsorbent Direct air capture

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Sensing nanoscale electromagnetic forces when the heat is on

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National Science Review 2024年第07期 64-65页

作者： Eric o.Potma Department of Chemistry University of California

In scanning probe microscopy(SPM),a sharp tip scans across a sample to produce an image with nanometer-scale resolution or better. SPM contrast is derived from the physical interplay between the tip and the sample. A special class of SPM techniques measures forces when the tip–sample junction is illuminated by an external light source. Photo-induced forces can be sensitive to the optical properties of the sample, thus enabling nanoscale imaging with spectroscopic,material-specific contrast.

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