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Surface wildfire in conifer broad-leaved forests of the Hyrcanian region of Iran:short-term effect on regeneration and damage to trees

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Journal of Forestry Research 2015年第2期26卷 425-434页

作者： Seyed Abdolkhalegh Yadegarnejad Mehdi Dylam Jafarabad Najmeh Mohammadi Savadkoohi department of Forestry Gorgan University of Agricultural Sciences and Natural Resources Forest Engineering Sari Agricultural Sciences and Natural Resources University

Wildfires in recent years have resulted in degradation and damage to the Hyrcanian forest ecosystems in Northern *** study was carried out to investigate fire damage to trees and changes in regeneration in early-season growth after wildfires in the Golestan *** this purpose,a random sampling plan was used,with 60 circular plots（each plot is 1000 m2） for each stand and 240 circular（25 m2） plots for regeneration within the burned and unburned areas,*** each plot,habitat factors were recorded,including crown canopy percentage,forest stratum,herb-layer cover percentage,species,diameter at breast height,tree and regeneration quality,and quantity of seedlings and *** results showed that bark is an important factor for fire resistance in Hyrcanian *** Persian ironwood and European yew has the highest and lowest fire resistance;as broad leave species are more resistant than needle leaf *** of regeneration in unburned area was higher than burned area,and statistical analysis showed significant differences for all species between two *** effects on sapling were different among species which indicates sapling has different resistance to *** floor fuel,season,stand composition and microclimate have more effects on fire severity while environmental factors,regeneration and management practices shaping future composition stands.

关键词： Broad leave European yew Seedling and sapling Wildfire

The Lanthanide Tetrad Effect in Argillic Alteration: An Example from the Jizvan District, Northern Iran

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1468-1485页

作者： Ali ABEDINI Mansour REZAEI AZIZI Ali Asghar CALAGARI department of Geology Faculty of Sciences Urmia University department of Earth sciences Faculty of Natural Sciences University of Tabriz

Intrusion of quartz-monzodioritic igneous bodies of Oligocene age into Eocene lithic crystal tufts and trachy-basalts resulted in the occurrence of a widespread argillic alteration zone in the Jizvan district （northern Iran）. Mineralogically, the argillie alteration zone includes minerals such as kaolinite, quartz, smectite, pyrophyllite, muscovite-illite, alunite, rutile, calcite, feldspar, chlorite, hematite and goethite. Therefore, the non-CHARAC behaviour for trace elements in the argillic samples is reflected in the non-chondritic Y/Ho and Zr/Hf ratios and the irregular REE patterns, which appear related to the tetrad effect phenomenon. The chondrite-normalized REE distribution patterns indicate both concave （W-shaped） and convex （M-shaped） tetrad effects in the argillic samples. Based on the field evidence and the results from geochemical studies, it can be concluded that the samples from the argillic alteration zone having high fourth tetrad effect values （〉0.30） were developed in the fault and breccia zones. The results indicate that factors such as preferential scavenging by Mn-oxides, crystallization of clay minerals, fluid-rock interaction, overprint of hypogene mineral assemblage by supergene ones, and the structural control, have all played an important role in the occurrence of tetrad effects in samples of the argillic zone in the Jizvan district.

关键词： REE geochemistry tetrad effect argillic alteration Jizvan Iran

ImSpiRE: image feature-aided spatial resolution enhancement method

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Science China Life sciences 2025年第1期68卷 272-283页

作者： Yuwei Hua Yizhi Zhang Zhenming Guo Shan Bian Yong Zhang State Key Laboratory of Cardiovascular Diseases and Medical Innovation Center Institute for Regenerative MedicineDepartment of NeurosurgeryShanghai East HospitalShanghai Key Laboratory of Signaling and Disease ResearchFrontier Science Center for Stem Cell ResearchSchool of Life Sciences and TechnologyTongji University

The resolution of most spatially resolved transcriptomic technologies usually cannot attain the single-cell level, limiting their applications in biological discoveries. Here, we introduce ImSpiRE, an image feature-aided spatial resolution enhancement method for in situ capturing spatial transcriptome. Taking the information stored in histological images, ImSpiRE solves an optimal transport problem to redistribute the expression profiles of spots to construct new transcriptional profiles with enhanced resolution, together with extending the gene expression profiles into unmeasured regions. Applications to multiple datasets confirm that ImSpiRE can enhance spatial resolution to the subspot level while contributing to the discovery of tissue domains, signaling communication patterns, and spatiotemporal characterization.

关键词： spatial transcriptome histological images spatial resolution enhancement

Evaluation of entomopathogenic Bacillus sphaericus isolated from Lombok beach area against mosquito larvae

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Asian Pacific Journal of Tropical Biomedicine 2016年第2期6卷 148-154页

作者： Bambang Fajar Suryadi Bagyo Yanuwiadi Tri Ardyati Suharjono Suharjono department of Biology Faculty of Mathematics Natural Sciences Mataram University department of Biology Faculty of Mathematics Natural Sciences Brawijaya University

Objective: To isolate, characterize and evaluate toxicity of Bacillus sphaericus(B. sphaericus) from beach area of Lombok ***: Soil was collected from determined locations and suspended in sterile physiological saline water. After heat shock was applied, suspension was spread on NYSM agar medium. Colonies grown were then observed and isolated. Colony, cell morphology,and biochemical/physiological characteristics were tested and compared to B. sphaericus2362 as standard. Initial toxicity testing was done against three species of mosquito larvae(Culex quinquefasciatus, Anopheles aconitus and Aedes aegypti) and isolates that showed more than 50% larvae killing will be assayed to obtain LC_(50) and LC_(90)values within 48 *** technique were conducted to obtain 16 s r DNA amplicon for sequencing and to detect toxin-expressing genes(using multiplex PCR).Results: Twenty isolates of B. sphaericus have been collected from 20 determined locations and their characteristics were in agreement with standard B. sphaericus characteristics. Bioassay testing showed that four isolates(namely isolate MNT, SLG, TJL2 and PLG) were mildly toxic against all larvae. The rests were either low toxic or non-toxic at *** analysis showed that all four isolates were clustered with other known mildly and highly toxic strains. The multiplex PCR result showed four toxic isolates owned 1–2bands from Bin toxin genes and three bands from Mtx toxin genes, whereas 16 isolates with low to non-toxic characteristics showed only three bands from Mtx toxin ***: Four toxic isolates of B. sphaericus were isolated from beach area of Lombok Island. They showed mild toxicity against larvae of three mosquito species.

关键词： Bacillus sphaericus Lombok Island Mosquito larvae Culex quinquefasciatus Anopheles aconitus Aedes aegypti

Tunable colors and conductivity by electroless growth of Cu/Cu2O particles on sol-gel modified cellulose

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Nano Research 2020年第10期13卷 2658-2664页

作者： Justus Landsiedel Waleri Root Christian Schramm Alexander Menzel Steffen Witzleben Thomas Bechtold Tung Pham Research Institute for Textile Chemistry and Textile Physics University of Innsbruck6850 DornbirnAustria department of physical Chemistry University of Innsbruck6020 InmsbruckAustria department of natural sciences Bonn Rhein sSieg University of Applied Sciences5359 RheinbachGermany

Development of colored surfaces by formation of nano-structured aggregates is a widely used strategy in nature to color lightweight structures (e.g. butterflies) without the use of dye pigments. The deposition of nanoscale particles mimics nature in it’s approach coloring surfaces. This work presents sol-gel modification of cellulose surfaces used to form a template for growth of Cu/Cu2O core–shell particles with defined size-distributions. Besides improving the adhesion of the deposited particulate material, the sol-gel matrix serves as a template for the control of particle sizes of the Cu/Cu2O structures, and as a consequence of particle size variation the surface color is tunable. As an example, red color was achieved with an average particle size of 35 nm, and shifts gradually to blue appearance when particles have grown to 80 nm on the sol-gel modified fabric. The copper concentration on representative fabrics is kept low to avoid modifying the textile characteristics and were all in the range of 150–170 mg per g of cellulose material. As a result of copper deposition on the surface of the material, the cellulose fabric also became electrically conductive. Remarkably, the electrical conductivity was found to be dependent on the average particle sizes of the deposits and thus related to the change in observed color. The generation of color by growth of nano-sized particles on sol-gel templates provides a highly promising approach to stain surfaces by physical effects without use of synthetic colorants, which opens a new strategy to improve environmental profile of coloration.

关键词： electroless copper deposition sol-gel support thin film structural coloration tunable sheet resistance LSPR

Decay pathways of superexcited states of nitrous oxide

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Chinese Physics B 2014年第5期23卷 253-256页

作者：林梅刘亚伟钟志萍朱林繁 Hefei National Laboratory for physical sciences at Microscale Department of Modern PhysicsUniversity of Science and Technology of China School of physical sciences University of the Chinese Academy of Sciences

The ionization and ionic dissociation of the superexcited state of N20 are studied by using electron energy loss spectroscopy and positive ion time-of-flight mass spectroscopy at different momentum transfers; that is, 0 and 0.23 a.u. （atomic unit） . The transitions at 13.8 eV and 14.0 eV are reassigned as 3pπ（000） and 3pσ（000） converging to A^2∑＋, respectively. The competition between the main decay pathways of superexcited states at different momentum transfers is revealed. It is found that 3dσ converging to C^2∑＋ mainly decays into N2O^＋ while 4dσ can decay into both N2^O＋ and NO^＋.

关键词： ionization continuum superexcited states decay channel nitrous oxide

Ce-substituted Lithium Ferrite:Preparation and Electrical Relaxation Studies

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Journal of Materials Science & Technology 2014年第4期30卷 335-341页

作者： Viswarupa Mohanty Rajesh Cheruku Lakshmi Vijayan G.Govindaraj department of Physics School of PhysicalChemical and Applied SciencesPondicherry University

Ce-substituted lithium ferrite, Li0.5CexFe2.5-x04 （x = 0, 0.05 and 0.1 ） compositions were synthesized from metal nitrates and citric acid by the solution combustion process by keeping the oxidizer to fuel ratio at unity. The thermal decomposition process was investigated by thermogravimetry-differential thermal analysis, which showed a stable phase formation above 600 ℃. The phase composition and molecular bonding of Li0.5CexFe2.5_x04 were characterized by X-ray powder diffraction analysis and Fourier transform infrared spectroscopy, respectively. An extensive study of electrical relaxation process has been represented with impedance and modulus as a function of frequency at different temperatures. The activation energy obtained from both the formalisms was found to be equal within the error. The dc conductivity and hopping frequency were thermally activated and their activation energies were found to be in the range of 0.69-0.64 eV for x = 0.05. The scaling of modulus and impedance were used to understand the electrical relaxation behaviour of the compositions and they suggest the time temperature superposition principle.

关键词： Lithium ferrite Solution combustion synthesis Inverse spinel Electrical relaxation process and scaling

Anisotropic transport properties and topological Hall effect in the annealed kagome antiferromagnet FeGe

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Science China(Physics,Mechanics & Astronomy) 2025年

作者： Jiajun Ma Chenfei Shi Yantao Cao Yuwei Zhang Yazhou Li Jiaxing Liao Jialu Wang Wenhe Jiao Hanjie Guo Chenchao Xu Shixun Cao Jianhui Dai Jin-Ke Bao Yuke Li School of Physics Hangzhou Key Laboratory of Quantum Matters Hangzhou Normal University department of Physics Materials Genome Institute and International Center for Quantum and Molecular StructuresShanghai University Songshan Lake Materials Laboratory School of physical Science and Technology Lanzhou University Key Laboratory of Quantum Precision Measurement of Zhejiang Province Department of Applied PhysicsZhejiang University of Technology

Electron correlation often gives birth to various orders in quantum materials. Recently, a strongly correlated kagome antiferromagnet FeGe is discovered to undergo a charge density wave transition inside the A-type antiferromagnetic state, providing an opportunity to explore the interplay between charge order and magnetism. Here, we reported the observation of anisotropic resistivity and Hall effect, along with a topological Hall effect, in the annealed FeGe crystals. As the current flows along the abplane, the temperature dependence of ρabexhibits a distinct resistivity loop related to a first-order transition at Tcdw. The applied magnetic fields do not alter Tcdwbut can induce a spin-flop transition at Hsf. Consequently, a field-induced large topological Hall effect is observed in the canting antiferromagnetic（CAFM） state below Tcant, which is possibly attributed to the non-trivial spin texture during the spin-flop process. Whereas, as current is parallel to c-axis, both the field-induced transitions in ρcand χcdisappear. Instead, the Hall resistivity in the annealed FeGe significantly exhibits a deviation from the linear *** findings provide valuable insight into revealing the interplay among magnetism, charge order and topology in the kagome magnets.

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Zero group velocity longitudinal modes in an isotropic cylinder

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Acta Mechanica Sinica 2018年第3期34卷 475-481页

作者： Takasar Hussain Faiz Ahmad Muhammad Ozair department of Mathematics COMSATS Institute of Information Technology School of natural sciences National University of Sciences and Technology

Zero group velocity （ZGV） modes are studied in an isotropic cylinder. The L （0, 2） mode behaves anomalously for the materials with a value of the bulk velocity ratio, to, in the range √2 〈 κ 〈 2.64 and normally otherwise. All higher modes, except the first few, have no ZGV point for all isotropic materials. This is explained analytically by finding the slope of phase velocity dispersion curves of modes first when the phase velocity equals κ and then at their initial state.

关键词： Isotropic cylinder Longitudinal modes Zerogroup velocity point