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Organic Chemistry Frontiers 2022年第5期9卷 1321-1326页

作者： Mateus L.Stivanin Rafael d.C.Gallo Joao Paulo M.Spadeto Rodrigo A.Cormanich igor d.jurberg State University of Campinas Institute of ChemistryRua Monteiro Lobato 27013083-862 CampinasSPBrazil

A blue light-promoted reaction between aryldiazoacetates and different nucleophiles has been developed in the presence of THF(and other cyclic ethers)as the solvent,allowing the incorporation of these three elements into a single ***,this transformation represents an O–H insertion strategy of more complex alcohols into aryldiazoesters,without the need of pre-assembling *** method is mild and efficient and proceeds in the absence of metals,generally at room temperature.

关键词： temperature visible light

Cortical hem signaling center: functions, development, and potential implications for evolution and brain disorders

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Neural Regeneration Research 2025年第4期20卷 1079-1080页

作者： Victor V.Chizhikov igor Y.Iskusnykh department of Anatomy and Neurobiology University of Tennessee Health Science CenterMemphisTNUSA

development of the telencephalon relies upon several signaling centers-localized cellular populations that supply secreted factors to pattern the cortical *** such signaling center is the cortical hem,which arises during embryonic development at the telencephalic dorsal midline,adjacent to the choroid plexus and hippocampal primordium(Figure 1A).While the cortical hem has also been described in reptiles and birds,most of our knowledge about the developmental roles of the cortical hem is derived from the analysis in *** cortical hem produces several types of secreted molecules,including wingless-related integration site(Wnt)and bone morphogenetic(Bmp)*** cortical hem is particularly important for the development of the hippocampus,which is involved in learning and memory,and the neocortex,which is the most complex brain region that mediates multiple types of behavior and higher cognitive functions(Mangale et al.,2008;dal-Valle-Anton and Borrell,2022).

关键词： epithelium Figure center

Security breach:peripheral nerves provide unrestricted access for toxin delivery into the central nervous system

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Neural Regeneration Research 2023年第1期18卷 64-67页

作者： igor Lupinski Allison SLiang Randall d.McKinnon department of Neurosurgery and Member The Cancer Institute of New JerseyRutgers-Robert Wood Johnson Medical SchoolPiscatawayNJUSA

We explore the hypothesis that a potential explanation for the initiation of motor neuron disease is an unappreciated vulnerability in central nervous system defense,the direct delivery of neurotoxins into motor neurons via peripheral nerve retrograde *** further suggests a mechanism for focal initiation of neuro-degenerative diseases in general,with subsequent spread by network degeneration as suggested by the Frost-diamond *** propose this vulnerability may be a byproduct of vertebrate evolution in a benign aquatic environment,where external surfaces were not exposed to concentrated neurotoxins.

关键词： amyotrophic lateral sclerosis bioaccumulation neurodegeneration neuropathology neurotoxins peripheral nerves retrograde transport retrotoxicity suicide transport

design of Resilient Sensor Networks Balancing Resilience and Efficiency

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International Journal of disaster Risk Science 2024年第1期15卷 107-115页

作者： Sergey N.Vecherin Kiril d.Ratmanski Luke Hogewood igor Linkov Cold Regions Research and Engineering Laboratory Engineering Research and Development CenterHanoverNH 03755USA Environmental Laboratory Engineering Research and Development CenterVicksburgMS 39180USA

In recent years,the notion of resilience has been developed and applied in many technical areas,becoming exceptionally pertinent to disaster risk *** a disaster situation,accurate sensing information is the key to efficient recovery *** general,resilience aims to minimize the impact of disruptions to systems through the fast recovery of critical functionality,but resilient design may require redundancy and could increase *** this article,we describe a method based on binary linear programming for sensor network design balancing efficiency with *** application of the developed framework is demonstrated for the case of interior building surveillance utilizing infrared sensors in both twoand three-dimensional *** method provides optimal sensor placement,taking into account critical functionality and a desired level of resilience and considering sensor type and *** problem formulation,resilience requirements,and application of the optimization algorithm are described in *** of sensor locations with and without resilience requirements shows that resilient configuration requires redundancy in number of sensors and their intelligent *** tasks are successfully solved by the described method,which can be applied to strengthen the resilience of sensor networks by *** proposed methodology is suitable for large-scale optimization problems with many sensors and extensive coverage areas.

关键词： Binary linear programming Optimal sensor placement Redundant networks Resilience and efciency Resilient sensor networks

Improved Peptidyl Linkers for Self-Assembly of Semiconductor Quantum dot Bioconjugates

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Nano Research 2009年第2期2卷 121-129页

作者： Lorenzo Berti Paola Serena d'Agostino Kelly Boeneman igor L.Medintz CNR-INFM National Research Center on nanoStructures and bioSystems at Surfaces(S3)Via Campi213/A 41100 ModenaItaly University of California davis Medical Center SacramentoCA 95817USA Center for Bio/Molecular Science and Engineering Code 6900 U.S.Naval Research LaboratoryWashingtonDC 20375USA

We demonstrate improved peptide linkers which allow both conjugation to biomolecules such as dNA and self-assembly with luminescent semiconductor quantum dots.A hexahistidine peptidyl sequence was generated by standard solid phase peptide synthesis and modified with the succinimidyl ester of iodoacetamide to yield a thiol-reactive iodoacetyl polyhistidine *** reactive peptide was conjugated to dye-labeled thiolated dNA which was utilized as a model target *** gel electrophoresis and fluorescence resonance energy transfer analysis confirmed that the linker allowed the dNA to self-assemble with quantum dots via metal-affinity driven *** contrast to previous peptidyl linkers that were based on disulfide exchange and were thus labile to reduction,the reactive haloacetyl chemistry demonstrated here results in a more stable thioether bond linking the dNA to the peptide which can withstand strongly reducing environments such as the intracellular *** thiol groups occur naturally in proteins,can be engineered into cloned proteins,inserted into nascent peptides or added to dNA during synthesis,the chemistry demonstrated here can provide a simple method for self-assembling a variety of stable quantum dot bioconjugates.

关键词： Semiconductor quantum dot peptide dNA nanocrystal bioconjugation iodoacetyl sulfhydryl polyhistidine metal-affinity fluorescence fluorescence resonance energy transfer(FRET)

Nonabelian Jacobian of smooth projective surfaces-a survey

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Science China Mathematics 2013年第1期56卷 1-42页

作者： REIdER igor département de Mathématiques l'Université d'Angers2 Boulevard Lavoisier49045 Angers Cedex 01France

The nonabelian Jacobian J(X;L,d) of a smooth projective surface X is inspired by the classical theory of Jacobian of *** is built as a natural scheme interpolating between the Hilbert scheme X [d] of subschemes of length d of X and the stack M X(2,L,d) of torsion free sheaves of rank 2 on X having the determinant OX(L) and the second Chern class(= number) *** relates to such influential ideas as variations of Hodge structures,period maps,nonabelian Hodge theory,Homological mirror symmetry,perverse sheaves,geometric Langlands *** relations manifest themselves by the appearance of the following structures on J(X;L,d):1) a sheaf of reductive Lie algebras;2)(singular) Fano toric varieties whose hyperplane sections are(singular) Calabi-Yau varieties;3) trivalent *** is an expository paper giving an account of most of the main properties of J(X;L,d) uncovered in Reider 2006 and ArXiv:1103.4794v1.

关键词： Jacobian Hilbert scheme vector bundle

Active catalytic species generated in situ in zirconia incorporated hydrogen storage material magnesium hydride

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Journal of Magnesium and Alloys 2022年第3期10卷 852-861页

作者： d.Pukazhselvan K.S.Sandhya devaraj Ramasamy Aliaksandr Shaula igor Bdikin duncan Paul Fagg department of Mechanical Engineering Nanoengineering Research GroupCentre for Mechanical Technology and Automation(TEMA)University of AveiroAveiro 3810-193Portugal department of Chemistry Malankara Catholic CollegeKaliyakkavilaiTamil Nadu 629153India department of Computational Biology and Bioinformatics University of KeralaThiruvananthapuramKerala 695581India UIdM ESTGPolytechnic Institute of Viana do CasteloViana do Castelo 4900Portugal

This study explores how zirconia additive interacts with MgH_(2)to improve its hydrogen storage *** it is confirmed that the zirconia added MgH_(2)powder releases hydrogen at a temperature of about 50℃below that of the additive free MgH_(2).Subsequent tests by X ray diffraction(XRd)and infrared(IR)spectroscopy techniques reveal that the ZrO_(2) mixed MgH_(2)powder contains ZrHx(21.5)and MgO secondary *** observation is supported by the negative Gibbs free energy values obtained for the formation of ZrH_(2)/MgO from ZrO_(2)/MgH_(2)powder *** X ray photoelectron spectroscopy(XPS)study reveals that apart from Zr^(4+)cations,Zr^(2+) and zero valent Zr exist in the *** force microscopy(AFM)study reveals that the average grain size is 20 nm and the elemental line scan profiles further proves the existence of oxygen deficient Zr bearing phase(s).This study strengthens the belief that functional metal oxide additives in fact chemically interact with MgH_(2)to make active in-situ catalysts in the MgH_(2)system.

关键词： Hydrogen storage Binary hydrides Metal oxides Additives Nanocatalysis.

New solutions for old challenges in glaucoma treatment:is taurine an option to consider?

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Neural Regeneration Research 2021年第5期16卷 967-971页

作者： igor Iezhitsa Renu Agarwal School of Medicine International Medical UniversityKuala LumpurMalaysia Volgograd State Medical University Research Centre for Innovative MedicinesVolgogradRussian Federation

Glaucoma is a range of progressive optic neuropathies characterized by progressive retinal ganglion cell loss and visual field *** is recognized as a leading cause of irreversible blindness affecting more than 70 million people ***,reduction of intraocular pressure,a widely recognized risk factor for glaucoma development,is the only pharmacological strategy for slowing down retinal ganglion cell loss and disease ***,retinal ganglion cell death and visual field loss have been observed in normotensive glaucoma,suggesting that the disease process is partially independent of intraocular *** is one of the agents that have attracted attention of researchers *** has been shown to be involved in multiple cellular functions,including a central role as a neurotransmitter,as a trophic factor in the central nervous system development,as an osmolyte,as a neuromodulator,and as a *** also plays a role in the maintenance of the structural integrity of the membranes and in the regulation of calcium transport and *** is known to prevent N-methyl-d-aspartic acid-induced excitotoxic injury to retinal ganglion cells.A recently published study clearly demonstrated that taurine prevents retinal neuronal apoptosis both in vivo and in *** effect of taurine may be attributed to direct inhibition of apoptosis,an activation of brain derived neurotrophic factor-related neuroprotective mechanisms and reduction of retinal oxidative and nitrosative *** studies are needed to fully explore the potential of taurine as a neuroprotective agent,so that it can be applied in clinical practice,particularly for the treatment of *** objective of current review was to summarize recent evidence on neuroprotective properties of taurine in glaucoma.

关键词： apoptosis excitotoxicity glaucoma oxidative and nitrosative stresses retinal neuroprotection taurine

Single‑Photon Sources Based on Novel Color Centers in Silicon Carbide P–I–N diodes: Combining Theory and Experiment

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Nano-Micro Letters 2021年第5期13卷 192-203页

作者： igor A.Khramtsov dmitry Yu.Fedyanin Laboratory of Nanooptics and Plasmonics Center for Photonics and 2D MaterialsMoscow Institute of Physics and Technology141700DolgoprudnyRussian Federation

Point defects in the crystal lattice of SiC,known as color centers,have recently emerged as one of the most promising single-photon emitters for non-classical light ***,the search for the best color center that satisfies all the requirements of practical applications has only just *** color centers in SiC have been recently discovered but not yet ***,it is extremely challenging to understand their optoelectronic properties and evaluate their potential for use in practical single-photon ***,we present a theoretical approach that explains the experiments on single-photon electroluminescence(SPEL)of novel color centers in SiC p-i-n diodes and gives the possibility to engineer highly efficient single-photon emitting diodes based on ***,we develop a novel method of determining the electron and hole capture cross sections by the color center from experimental measurements of the SPEL rate and second-order *** other methods,the developed approach uses the experimental results at the single defect level that can be easily obtained as soon as a single-color center is identified in the i-type region of the SiC p-i-n diode.

关键词： Color centers Electron capture cross section Single-photon emitting diodes Single-photon electroluminescence Charge state control

On character sums with determinants

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Science China Mathematics 2023年第12期66卷 2693-2714页

作者： Etienne Fouvry igor E.Shparlinski CNRS Laboratoire de Mathématiques d'OrsayUniversité Paris-SaclayOrsay 91405France School of Mathematics and Statistics University of New South WalesSydneyNSW 2052Australia

We estimate weighted character sums with determinants ad-bc of 2×2 matrices modulo a prime p with entries a,b,c and d vary ing over the interval [1,N].Our goal is to obtain non-trivial bounds for values of N as small as *** particular,we achieve this goal,with a power saving,for N≥p^(1/8+ε) with any fixed ε>0,which is very likely to be the best possible unless the celebrated Burgess bound is improved,By other techniques,we also treat more general sums but sometimes for larger values of N.

关键词： character sum determinant Burgess bound