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Genetic distinctness of parthenogenetic forms of European Polydrusus weevils of the subgenus Scythodrusus

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Insect Science 2012年第2期19卷 183-194页

作者： Lukasz Kajtoch boris Korotyaev Dorota Lachowska-Cierlik Institute of Systematics and Evolution of Animals Polish Academy of Sciences Krakow Poland Zoological Institute Russian Academy of Sciences St. Petersburg Russia Institute of Zoology Jagiellonian University Krakow Poland

Among eight species of Polydrusus weevils which belong to subgenus Scythodrusus, at least two possess parthenogenetic forms： P （S.） inustus and P （S.）pilifer. Both of these species consist of dioecious populations in the Caspian area and of parthenogenetic populations in Eastern Europe （R （S.） inustus）, the Caucasus region （both species） and Middle Asia （P （S.）pilifer）. The origin of parthenogenesis in this subgenus is unresolved; however some data suggest that the parthenogenetic forms are of hybrid ancestry. The genetic distinctness of parthenogenetic Scythodrusus was assessed on the basis of COII, ITS2, EFI-a and Wolbachia wsp, 16S ribosomal DNA, ftsZ and hcpA sequence comparisons. Both taxa turned out to be monophyletic for all markers, which is an evidence against hybridization of their dioecious ancestors. On the other hand, a high frequency of heterozygous P （S.） inustus females suggests an origin resulting from hybridization between genetically distinct dioecious representatives of this species. Very similar strains of Wolbachia supergroup A were found in both species, indicating that they have been either inherited from a common ancestor or were transmitted between parthenogenetic Scythodrusus weevils and probably spread randomly across their ranges.

关键词： Coleoptera Curculionidae hybridization parthenogenesis phylogeny Polydrusus Wolbachia

Morphological control of cadmium sulfide nanostructures by electrophoretic deposition

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Particuology 2016年第1期14卷 73-77页

作者： Alejandro Vazquez Thelma Serrano boris Kharisov Idalia Gomez Universidad Autonoma de Nuevo Leon UANL Facultad de Ciencias Quimicas Av. Universidad S/N San Nicolas de los Garza Nuevo Leon 66451 Mexico

Thin films and one-dimensional CdS nanostructures were formed by electrophoretic deposition of nanoparticles with morphological control, Particles less than 1Ohm in diameter were prepared by a microwave assisted synthesis using trisodium citrate as capping agent. The particles were character- ized by UV-Vis spectrophotometry, dynamic light scattering, and X-ray diffraction. Nanoparticles in the resulting aqueous dispersion were electrodeposited without any further treatment on aluminum plates. The nanostructures consisted of thin films with surface roughness being tuned with the applied voltage. One-dimensional nanostructures were formed by varying the applied voltage and by changing the molar ratio of the precursors in the nanocrystal synthesis. These results illustrate two different mechanisms of electrophoretic deposition that lead to the formation of different nanostructures,

关键词： Electrophoretic deposition Nanostructure Nanoparticle

Diploidy in evolutionary algorithms for dynamic optimization problems A best-chromosome-wins dominance mechanism

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International Journal of Intelligent Computing and Cybernetics 2015年第4期8卷 312-329页

作者： boris Shabash Kay C.Wiese School of Computing Science Simon Fraser UniversityBurnabyCanada

Purpose–In this work,the authors show the performance of the proposed diploid scheme(a representation where each individual contains two genotypes)with respect to two dynamic optimization problems,while addressing drawbacks the authors have identified in previous works which compare diploid evolutionary algorithms(EAs)to standard *** paper aims to discuss this ***/methodology/approach–In the proposed diploid representation of EA,each individual possesses two copies of the *** order to convert this pair of genotypes to a single phenotype,each genotype is individually evaluated in relation to the fitness function and the best genotype is presented as the *** order to provide a fair and objective comparison,the authors make sure to compare populations which contain the same amount of genetic information,where the only difference is the arrangement and interpretation of the *** two representations are compared using two shifting fitness functions which change at regular intervals to displace the global optimum to a new ***–For small fitness landscapes the haploid(standard)and diploid algorithms perform comparably and are able to find the global optimum very ***,as the search space increases,rediscovering the global optimum becomes more difficult and the diploid algorithm outperforms the haploid algorithm with respect to how fast it relocates the new *** both algorithms use the same amount of genetic information,it is only fair to conclude it is the unique arrangement of the diploid algorithm that allows it to explore the search space ***/value–The diploid representation presented here is novel in that instead of adopting a dominance scheme for each allele(value)in the vector of values that is the genotype,dominance is adopted across the entire genotype in relation to its *** a result,this representation can be extended across any alphabet,for any optimization function.

关键词： Evolutionary computation Genetic algorithms Diploidy Dynamic optimization

Geoacoustic Inversion Using Time Reversal of Ocean Noise

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Chinese Physics Letters 2017年第9期34卷 62-65页

作者： Ji-Xing Qin boris Katsnelson Oleg Godin Zheng-Lin Li State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190 Department of Marine Geosciences School of Marine SciencesUniversity of HaifaHaifa 31905Israel Cooperative Institute for Research in EnvironmentM Sciences University of Colorado BoulderColorado 80309 USA

We present a passive geoacoustic inversion method using two hydrophones, which combines noise interferometry and time reversal mirror （TRM） techniques. Numerical simulations are firstly performed, in which strong fo- cusing occurs in the vicinity of one hydrophone when Green＇s function （GF） is back-propagated from the other hydrophone, with the position and strength of the focus being sensitive to sound speed and density in the bottom. We next extract the GF from the noise cross-correlation function measured by two hydrophones with 8025-m distance in the Shallow Water ＇06 experiment. After realizing the TRM process, sound speed and density in the bottom are inverted by optimizing focusing of the back-propagated GF. The passive inversion method is inherently environmentally friendly and low-cost.

关键词： Geoacoustic Inversion Using Time Reversal of Ocean Noise GF

Mechanism of the Initial Stage of Thermal Decomposition of Nitroguanidine

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火炸药学报 2023年第1期46卷 31-40页

作者： boris E.Krisyuk Danila A.Markin Timofey M.Sypko Viktor V.Zakharov Nikita V.Chukanov boris L.Korsunskiy Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry Russian Academy of Sciences142432prosp.Academician Semenov1ChernogolovkaMoscow RegionRussia Plekhanov Russian University of Economics Department of Chemistry and Physics36 Stremyanny laneMoscow 117997Russia Lomonosov Moscow State University Faculty of Fundamental Physical and Chemical engineeringGSP-11 Leninskie Goryp.51Moscow 119991Russia N.N.Semenov Federal Research Center for Chemical Physics Russian Academy of Science 4 Kosygina StreetBuilding 1Moscow 119991Russia

A theoretical and experimental study of the thermal decomposition of nitroguanidine(NQ) has been carried out. Various thermolysis channels were studied by quantum chemistry methods at the CCSD(or DLPNO-CCSD) level using the aug-cc-pVDZ basis set. It is shown that the lowest activation enthalpies(170-180kJ/mol) are characteristic of the reactions of NO2abstraction from the initial NQ and the reaction channel with the transfer of oxygen from the nitro group to carbon in the limiting stage. Additionally, the thermolysis of NQ was studied experimentally in a nonisothermal mode with heating rates from 1 to 10K/min. In these experiments, the weight loss of the sample, thermal effects, and mass spectra of the products were recorded. An analysis of the experimental data confirmed the results of a theoretical study of the mechanism of thermal decomposition of NQ. The main thermolysis products are N2O, HNCO, NH3, and NO2, which fully corresponds to quantum chemical calculations.

关键词： primary thermolysis steps quantum-chemical calculation mass spectrometry DSC TG

A version of Geiringer-like theorem for decision making in the environments with randomness and incomplete information

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International Journal of Intelligent Computing and Cybernetics 2012年第1期5卷 36-90页

作者： boris Mitavskiy Jonathan Rowe Chris Cannings Department of Computer Science Aberystwyth UniversityAberystwythUK School of Computer Science University of BirminghamBirminghamUK School of Mathematics and Statistics University of SheffieldSheffieldUK

Purpose-The purpose of this paper is to establish a version of a theorem that originated from population genetics and has been later adopted in evolutionary computation theory that will lead to novel Monte-Carlo sampling algorithms that provably increase the AI ***/methodology/approach-In the current paper the authors set up a mathematical framework,state and prove a version of a Geiringer-like theorem that is very well-suited for the development of Mote-Carlo sampling algorithms to cope with randomness and incomplete information to make ***-This work establishes an important theoretical link between classical population genetics,evolutionary computation theory and model free reinforcement learning *** only may the theory explain the success of the currently existing Monte-Carlo tree sampling methodology,but it also leads to the development of novel Monte-Carlo sampling techniques guided by rigorous mathematical *** implications-The theoretical foundations established in the current work provide guidance for the design of powerful Monte-Carlo sampling algorithms in model free reinforcement learning,to tackle numerous problems in computational ***/value-Establishing a Geiringer-like theorem with non-homologous recombination was a long-standing open problem in evolutionary computation *** from overcoming this challenge,in a mathematically elegant fashion and establishing a rather general and powerful version of the theorem,this work leads directly to the development of novel provably powerful algorithms for decision making in the environment involving randomness,hidden or incomplete information.

关键词： Decision making Programming and algorithm theory Monte Carlo methods Markov processes Reinforcement learning Partially observable Markov decision processes Monte Carlo tree search Geiringer theorem Evolutionary computation theory Markov chains

Sirolimus,bevacizumab,5-Fluorouracil and irinotecan for advanced colorectal cancer:A pilot study

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World Journal of Gastroenterology 2009年第34期15卷 4278-4283页

作者： Francois Ghiringhelli boris Guiu Bruno Chauffert Sylvain Ladoire Department of Medical Oncology Georges-Francois Leclerc Cancer Center Department of Radiology Georges-Francois Leclerc Cancer Center

AIM： To evaluate the efficacy and the safety of combined 5-Fluorouracil, irinotecan, bevacizumab and sirolimus in refractory advanced colorectal carcinoma. METHODS： We initiated a regimen with at day 1 an injection （iv） of bevacizumab at 5 mg/kg, followed by 180 mg/m^2 irinotecan, followed by Leucovorin 400 mg/m^2, followed by a 5-Fluorouracil bolus 400 mg/m^2 and a 46-h infusion 2400 mg/m^2. Sirolimus was given orally as continuous administration of 2 mg twice a day every days. This treatment was repeated every 14 d. RESULTS： A total of 12 patients were enrolled. All patients presented with metastatic disease that had failed at least three lines of chemotherapy that contained oxaliplatin, irinotecan and bevacizumab. Cetuximab failure was also observed in all K-Ras wildtype patients. The median number of cycles was 8.5 （range 2-20） and clinical benefit was observed in eight patients. The median time to progression was 5 mo and the median survival was 8 too. Grade 3 neutropenia developed in four patients, and grade 3 diarrhea and stomatitis in ***： The combination regimen of 5-Fluorouracil,irinotecan, bevacizumab and sirolimus in advanced colorectal carcinoma after failure of dassical *** is feasible and promising. Further evaluation of this combination is required.

关键词： Colorectal cancer Bevacizumab 5-Fluorouracil Irinotecan Sirolimus Antineoplastic combinedchemotherapy protocols Angiogenesis

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宇宙主义与永生技术

艺术当代 2024年第1期23卷 16-21页

作者：鲍里斯·格罗伊斯翁晨(译) 纽约大学上海当代艺术博物馆复旦大学外文系

全球化使人们更加意识到自己与世界各地事件及宇宙事件的关联,如太阳活动与政治、社会生活之间的关系。20世纪初,费多罗夫提出宇宙主义,主张通过技术和社会组织实现已故之人的复活,并对技术与历史进步之间的关系提出逆向拷问。博物馆被... 详细信息

全球化使人们更加意识到自己与世界各地事件及宇宙事件的关联,如太阳活动与政治、社会生活之间的关系。20世纪初,费多罗夫提出宇宙主义,主张通过技术和社会组织实现已故之人的复活,并对技术与历史进步之间的关系提出逆向拷问。博物馆被认作是一种“面向过去的技术”,人类可以被赋予博物馆式的不朽性。不同于福柯现代国家的“生命权”,费多罗夫认为国家应该克服个体的自然死亡,以达到“彻底的生命权”,而艺术与政治、生命与技术、国家与博物馆的同化则是实现这种彻底性的手段。

关键词：宇宙主义博物馆星际旅行生命权

Bayesian force fields from active learning for simulation of inter-dimensional transformation of stanene

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npj Computational Materials 2021年第1期7卷 361-370页

作者： Yu Xie Jonathan Vandermause Lixin Sun Andrea Cepellotti boris Kozinsky John A.Paulson School of Engineering and Applied Sciences Harvard UniversityCambridgeMAUSA Robert Bosch LLC Research and Technology CenterCambridgeMAUSA

We present a way to dramatically accelerate Gaussian process models for interatomic force fields based on many-body kernels by mapping both forces and uncertainties onto functions of low-dimensional *** allows for automated active learning of models combining near-quantum accuracy,built-in uncertainty,and constant cost of evaluation that is comparable to classical analytical models,capable of simulating millions of *** this approach,we perform large-scale molecular dynamics simulations of the stability of the stanene *** discover an unusual phase transformation mechanism of 2D stanene,where ripples lead to nucleation of bilayer defects,densification into a disordered multilayer structure,followed by formation of bulk liquid at high temperature or nucleation and growth of the 3D bcc crystal at low *** presented method opens possibilities for rapid development of fast accurate uncertainty-aware models for simulating long-time large-scale dynamics of complex materials.

关键词： transformation dimensional fields