检索结果-南通市图书馆

npj Computational Materials 2020年第1期6卷 956-963页

作者： Nikolay Borodinov Matthias Lorenz Steven T.King Anton v.Ievlev olga S.Ovchinnikova Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37831USA University of Tennessee KnoxvilleTNUSA

Mass spectrometry imaging(MSI)plays a pivotal role in investigating the chemical nature of complex systems that underly our understanding in biology and *** fields of life science such as proteomics,lipidomics and metabolomics benefit from the ability to simultaneously identify molecules and pinpoint their distribution across a ***,achieving the necessary submicron spatial resolution to distinguish chemical differences between individual cells and generating intact molecular spectra is still a challenge with any single imaging ***,we developed an approach that combines two MSI techniques,matrix-assisted laser desorption/ionization(MALDI)and time-of-flight secondary ion mass spectrometry(ToF-SIMS),one with low spatial resolution but intact molecular spectra and the other with nanometer spatial resolution but fragmented molecular signatures,to predict molecular MSI spectra with submicron spatial resolution.

关键词： modal mass constrained

The forecast of fire impact on Pinus sylvestris renewal in southwestern Siberia

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Forestry Research 2021年第5期32卷 1911-1919页

作者： Stanislav NSannikov Nelly SSannikova Irina vPetrova olga E.Cherepanova Botanical Garden of the Ural Branch of Russian Academy of Science 202a8 Marta St.Yekaterinburg 620144Russia

Simulation of fire impact on forest floor renewal in pine forests was based on predictions for 2100 by the Canadian Climate Centre for increase in temperatures of by4.5℃and total precipitation by 14%in the West Siberian pre-forest-steppes and empirical regression relationships between them and the degree of burnt forest floor,as well as amount of Pinus sylvestris *** was predicted that by 2100,pine regeneration on fire prone sites under the canopy of the dominant forest type will increase by 29-54%compared to the 1980 s but on adjacent open sites,regeneration will decrease twice as *** means that the regeneration potential and pine population stability in pre-forest-steppes will become as poor as it is today.

关键词： Fire Forecast Stability Population Mathematical model Seeds Imitation model Undergrowth

Canine distemper virus as a threat to wild tigers in Russia and across their range

在线全文

学校读者我要写书评

暂无评论

Integrative Zoology 2015年第4期10卷 329-343页

作者： Martin GILBERT Svetlana v.SOUTYRINA Ivan v.SERYODKIN Nadezhda SULIKHAN olga v.UPHYRKINA Mikhail GONCHARUK Louise MATTHEWS Sarah CLEAvELAND Dale G.MIQUELLE Wildlife Conservation Society BronxNew YorkUSA Boyd Orr Centre for Population and Ecosystem Health Institute of BiodiversityAnimal Health and Comparative MedicineCollege of MedicalVeterinary and Life SciencesUniversity of GlasgowGlasgowUK Pacific Geographical Institute Far Eastern Branch of the Russian Academy of SciencesVladivostokRussia Far Eastern Federal University VladivostokRussia Institute of Biology and Soil Sciences Far Eastern Branch of the Russian Academy of SciencesVladivostokRussia Lazovskii State Nature Zapovednik LazoPrimorskii KraiRussia

Canine distemper virus(CDv)has recently been identified in populations of wild tigers in Russia and *** populations are generally too small to maintain CDv for long periods,but are at risk of infections arising from more abundant susceptible hosts that constitute a reservoir of *** CDv is an additive mortality factor,it could represent a significant threat to small,isolated tiger *** Russia,CDv was associated with the deaths of tigers in 2004 and 2010,and was coincident with a localized decline of tigers in Sikhote-Alin Biosphere Zapovednik(from 25 tigers in 2008 to 9 in 2012).Habitat continuity with surrounding areas likely played an important role in promoting an ongoing *** recommend steps be taken to assess the presence and the impact of CDv in all tiger range states,but should not detract focus away from the primary threats to tigers,which include habitat loss and fragmentation,poaching and retaliatory *** priorities include:(i)recognition and diagnosis of clinical cases of CDv in tigers when they occur;and(ii)collection of baseline data on the health of wild *** infection of individual tigers need not imply a conservation threat,and modeling should complement disease surveillance and targeted research to assess the potential impact to tiger populations across the range of ecosystems,population densities and climate extremes occupied by *** the role of domestic and wild carnivores as contributors to a local CDv reservoir is an important precursor to considering control measures.

关键词： canine distemper virus conservation threat extinction Panthera tigris altaica population decline

Alterations of morphology of lymphoid organs and peripheral blood indicators under the influence of gold nanoparticles in rats

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Innovative Optical Health Sciences 2016年第1期9卷 47-56页

作者： Alla B.Bucharskaya Svetlana S.Pakhomy olga v.Zlobina Galina N.Maslyakova olga v.Matveeva Irina O.Bugaeva Nikita A.Navolokin Boris N.Khlebtsov vladimir A.Bogatyrev Nikolai G.Khlebtsov valery v.Tuchin Saratov State Medical University 112 B.Kazach'ya str.Saratov 410012Russia Institute of Biochemistry and Physiology of Plants and Microorganisms RAS 13 Entuziastov Prospekt.Saratov 410049Russia Saratov State University 83 Astrakhanskaya str.Saratov 410012Russia§Institute of Precise Mechanics and Control of Russian Academy of Sciences 24Rabochaya str.Saratov 410028Russia Interdisciplinary Laboratory of Biophotonics Tomsk State University 36 Lenina str.Tomsk 634050Russia

At present,gold nanoparticles(GNPs)are widely used in biomedical applications such as cancer diagnostics and ***,the potential toxicity hazards of these nanomaterials and human safety concerns are gaining significant ***,we report the effects of prolonged peroral administration of GNPs with different sizes(2,15 and 50 nm)on morphological changes in lymphoid organs and indicators of peripheral blood of laboratory *** experiment was conducted on 24 white mongrel male rats weighing 180–220 g,gold nanospheres sizes 2,15 and 50nm were administered orally for 15 days at a dosage of 190g/kg of animal body *** GNPs were conjugated with polyethylene glycol to increase their biocompatibility and *** size-dependent decrease of the number of neutrophils and lymphocytes was noted in the study of peripheral blood,especially pronounced after administration of GNPs with size of 50 *** stimulation of myelocytic germ of hematopoiesis was recorded at morphological study of the bone *** signs of strengthening of the processes of differentiation and maturation of cellular elements were found in lymph nodes,which were showed as the increasing number of immunoblasts and large *** quantitative changes of cellular component morphology of lymphoid organs due to activation of migration,proliferation and di®erentiation of immune cells indicate the presence of immunostimulation effect of GNPs.

关键词： Gold nanoparticles lymphoid organs morphological changes bone marrow examination

Territorial Resilience Through visibility Analysis for Immediate Detection of Wildfires Integrating Fire Susceptibility,Geographical Features,and Optimization Methods

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Disaster Risk Science 2022年第4期13卷 621-635页

作者： Stavros Sakellariou George Sfoungaris olga Christopoulou Department of Agriculture Crop Production and Rural Environment University of Thessaly38446 VólosGreece Department of Planning and Regional Development University of Thessaly38334 VólosGreece Computer Science Department University of Crete70013 HeraklionCreteGreece

Climate change effects tend to reinforce the frequency and severity of wildfires worldwide,and early detection of wildfire events is considered of crucial *** primary aim of this study was the spatial optimization of fire resources(that is,watchtowers)considering the interplay of geographical features(that is,simulated burn probability to delimit fire vulnerability;topography effects;and accessibility to candidate watchtower locations)and geo-optimization techniques(exact programming methods)to find both an effective and financially feasible solution in terms of visibility coverage in Chalkidiki Prefecture of northern *** integration of all geographical features through the Analytical Hierarchy Process indicated the most appropriate territory for the installment of *** analysis guaranteed the independence and proximity of location options(applying spatial systematic sampling to avoid first order redundancy)across the *** conjunction of the above processes yielded 654 candidate watchtower positions in 151,890 ha of *** algorithm was designed to maximize the joint visible area and simultaneously minimize the number of candidate locations and overlapping effects(avoiding second order redundancy).The results indicate four differentiated location options in the study area:(1)75locations can cover 90%of the forests(maximum visible area);(2)47 locations can cover 85%of the forests;(3)31locations can cover 80.2%of the forests;and(4)16 locations can cover 70.6%of the *** last option is an e fficient solution because it covers about 71%of the forests with just half the number of watchtowers that would be required for the third option with only about 10%additional forest ***,the final choice of any location scheme is subject to agency priorities and their respective financial flexibility.

关键词： Burn probability Greece Spatial optimization Topography effects viewshed coverage Watchtowers Wildfire detection

Bacterial melanin promotes recovery after sciatic nerve injury in rats

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2015年第1期10卷 124-127页

作者： olga.v.Gevorkyan Irina B.Meliksetyan Tigran R.Petrosyan Anichka S.Hovsepyan Institute of Physiology National Academy of Sciences of Armenia Department of Kinesiology Armenian State Institute of Physical Culture Scientific and Production Center "Armbiotechnology" National Academy of Sciences of Armenia

Bacterial melanin, obtained from the mutant strain of Bacillus Thuringiensis, has been shown to promote recovery after central nervous system injury. It is hypothesized, in this study, that bacterial melanin can promote structural and functional recovery after peripheral nerve injury. Rats subjected to sciatic nerve transection were intramuscularly administered bacterial melanin. The sciatic nerve transected rats that did not receive intramuscular administration of bacterial melanin served as controls. Behavior tests showed that compared to control rats, the time taken for instrumental conditioned reflex recovery was significantly shorter and the ability to keep the balance on the rotating bar was significantly better in bacterial melanin-treated rats. Histomor- phological tests showed that bacterial melanin promoted axon regeneration after sciatic nerve injury. These findings suggest that bacterial melanin exhibits neuroprotective effects on injured sciatic nerve, contributes to limb motor function recovery, and therefore can be used for rehabil- itation treatment of peripheral nerve injury.

关键词： nerve regeneration peripheral nerve injury sciatic nerve injury bacterial melanin motor function histomorphology behaviors neural regeneration

Catalytic performance of ternary Mg-Al-Ce oxides for ethanol conversion into 1-butanol in a flow reactor

在线全文

学校读者我要写书评

暂无评论

燃料化学学报 2021年第3期49卷 346-357,I0001-I0010页

作者： olga v.Larina Karina v.valihura Pavlo I.Kyriienko Nina v.vlasenko Dmytro Yu.Balakin Ivan Khalakhan Katerina veltruská Tomaz Cendak Sergiy O.Soloviev Svitlana M.Orlyk L.v.Pisarzhevsky Institute of Physical Chemistry of the National Academy of Sciences of Ukraine 31 Prosp.Nauky03028 KyivUkraine Institute of Physics of the National Academy of Sciences of Ukraine 46 Prosp.Nauky03028 KyivUkraine Charles University Faculty of Mathematics and PhysicsDepartment of Surface and Plasma ScienceV Holešovičkách 218000 PragueCzech Republic National Institute of Chemistry Department of Inorganic Chemistry and TechnologyHajdrihova 19SI-1001 LjubljanaSlovenia

An investigation of hydrotalcite-derived ternary Mg-Al-Ce oxides as catalysts for vapour phase condensation of ethanol to 1-butanol in a flow reactor under atmospheric pressure was carried *** Mg-Al-Ce oxide systems with Mg/(Al+Ce)ratio from 1 to 4 were synthesized and characterized by XRD,SEM,NMR,and *** study of acid-base characteristics of the systems with different Mg/(Al+Ce)ratio by NH3/CO_(2)quasi-equilibrium thermal desorption techniques shows that the ratio of the catalyst oxide components(Mg,Al,Ce)can provide acid/base capacity ratio close to 3 for the effectivity of the target *** highest selectivity 68%is reached over Mg-Al-Ce oxide catalyst with the ratio of Mg/(Al+Ce)=2.

关键词： ethanol 1-butanol Mg-Al-Ce hydrotalcite-derived oxides acid-base properties

Extended Corey-Chaykovsky reactions:transformation of 2-hydroxychalcones to benzannulated 2,8-dioxabicyclo[3.2.1]octanes and 2,3-dihydrobenzofurans

在线全文

学校读者我要写书评

暂无评论

Organic Chemistry Frontiers 2022年第3期9卷 737-744页

作者： Alexander A.Fadeev Anton S.Makarov olga A.Ivanova Maxim G.Uchuskin Igor v.Trushkov Department of Chemistry Perm State UniversityBukireva 15Perm 614990Russian Federation Department of Chemistry M.V.Lomonosov Moscow State UniversityLeninskie Gory 1-3Moscow 119991Russian Federation N.D.Zelinsky Institute of Organic Chemistry Leninsky pr.47Moscow 119334Russian Federation. D.Rogachev National Medical Research Center of Pediatric Hematology Oncology and ImmunologySamory Mashela 1Moscow 117997Russian Federation

We report the divergent synthesis of benzannulated 2,8-dioxabicyclo[3.2.1]octanes and 2,3-dihydrobenzofurans using the concept of extended Corey-Chaykovsky *** this concept,2-hydroxychalcones were treated with the Corey ylide providing highly reactive donor-acceptor cyclopropanes that were introduced in a one pot manner for further transformations.

关键词： octane donor

Deep neural networks for understanding noisy data applied to physical property extraction in scanning probe microscopy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

npj Computational Materials 2019年第1期5卷 932-939页

作者： Nikolay Borodinov Sabine Neumayer Sergei v.Kalinin olga S.Ovchinnikova Rama K.vasudevan Stephen Jesse Center for Nanophase Materials Science Oak Ridge National LaboratoryOak RidgeTN 37831USA

The rapid development of spectral-imaging methods in scanning probe,electron,and optical microscopy in the last decade have given rise for large multidimensional *** many cases,the reduction of hyperspectral data to the lower-dimension materialsspecific parameters is based on functional fitting,where an approximate form of the fitting function is known,but the parameters of the function need to be ***,functional fits of noisy data realized via iterative methods,such as least-square gradient descent,often yield spurious results and are very sensitive to initial ***,we demonstrate an approach for the reduction of the hyperspectral data using a deep neural network approach.A combined deep neural network/least-square approach is shown to improve the effective signal-to-noise ratio of band-excitation piezoresponse force microscopy by more than an order of magnitude,allowing characterization when very small driving signals are used or when a material’s response is weak.

关键词： neural networks property

Comparison of growth mechanisms of undoped and nitrogen-doped carbon nanofibers on nickel-containing catalysts

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Catalysis 2016年第1期37卷 169-176页

作者： vladimir v.Chesnokov olga Yu.Podyacheva Alexander N.Shmakov Lidiya S.Kibis Andrei I.Boronin Zinfer R.Ismagilov 鲍列斯科夫催化研究所新西伯利亚国立大学煤炭化学和材料科学研究所

The growth mechanisms of carbon nanofibers on Ni catalysts and nitrogen-doped carbon nanofibers on Ni and Ni-Cu catalysts were *** growth of both types of nanofibers was found to occur by a mechanism that included the formation of surface non-stoichiometric nickel carbide followed by the dissolution and diffusion of carbon,or carbon and nitrogen into the bulk of the catalyst particles.

关键词： Carbon nanofibers Nitrogen doping Growth mechanism Nickel-based catalyst