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Howl variation across Himalayan, North African, Indian, and Holarctic wolf clades： tracing divergence in the world＇s oldest wolf lineages using acoustics

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current Zoology 2017年第3期63卷 341-348页

作者： Lauren HENNELLY Bilal HABIB Holly root-GUTTERIDGE Vicente PALAcIOS Daniela PASSILONGO Department of Animal Ecology and conservation Biology Wildlife Institute of India Dehradun India Department of Biology Syracuse University New York 13210 USA cavanilles Institute for Biodiversity and Evolutionary Biology University of Valencia Avenue de Blasce Ibanez Valencia 46010 Spain Ricerca sulla Selvaggina e sui Miglioramenti Ambientali a Fini Faunistici (c.I.R.Se.M.A.E) Piazzale delle Cascine 18 Firenze 1-50144 Italy

Vocal divergence within species often corresponds to morphological, environmental, and genetic differences between populations. Wolf howls are long-range signals that encode individual, group, and subspecies differences, yet the factors that may drive this variation are poorly understood. Furthermore, the taxonomic division within the canis genus remains contended and additional data are required to clarify the position of the Himalayan, North African, and Indian wolves within canis lupus. We recorded 451 howls from the 3 most basal wolf lineages-Himalayan c. lupus chanco-Himalayan haplotype, North African c. lupus lupaster, and Indian c. lupus pallipes wolves-and present a howl acoustic description within each clade. With an additional 619 howls from 7 Holarctic subspecies, we used a random forest classifier and principal component analysis on 9 acoustic parameters to assess whether Himalayan, North African, and Indian wolf howls ex- hibit acoustic differences compared to each other and Holarctic wolf howls. Generally, both the North African and Indian wolf howls exhibited high mean fundamental frequency （F0） and short duration compared to the Holarctic clade. In contrast, the Himalayan wolf howls typically had lower mean F0, unmodulated frequencies, and short howls compared to Holarctic wolf howls. The Himalayan and North African wolves had the most acoustically distinct howls and differed significantly from each other and to the Holarctic wolves. Along with the influence of body size and environmental differences, these results suggest that genetic divergence and/or geographic distance may play an important role in understanding howl variation across subspecies.

关键词： acoustic variation canis lupus geographic variation mammal communication.

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Seimatoric acid and colletonoic acid:Two new compounds from the endophytic fungi,Seimatosporium *** colletotrichum sp.

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chinese chemical Letters 2014年第12期25卷 1577-1579页

作者： Hidayat Hussain Natalia root Farah Jabeen Ahmed Al-Harrasi Ahmed Al-Rawahi Manzoor Ahmad Zahid Hassan Ghulam Abbas Fazal Mabood Afzal Shah Amin Badshah Amjad Khan Riaz Ahmad Ivan R.Green Siegfried Draeger Barbara Schulz Karsten Krohn Department of chemistry University of PaderbornWarburger Strasse 100Paderborn 33098Germany UoN chair of Oman's Medicinal Plants and Marine Natural Products University of NizwaP.O.Box 33Postal Code 616Birkat Al MauzNizwaOman Department of chemistry University of MalakandChakdaraDir(L)Pakistan Department of chemistry CIITAbbottabad CampusAbbottabad 22060Pakistan Department of chemistry Quaid-i-Azam UniversityIslamabad 45320Pakistan Department of Biotechnology Quaid-i-Azam UniversityIslamabad 45320Pakistan Department of chemistry and Polymer Science University of StellenboschP/Bag X1Matieland 7602South Africa Institute of Microbiology University of BraunschweigSpielmannstraβe 7Braunschweig 38106Germany

A new metabolite,named seimatoric acid（1）,representing a new oxobutanoic acid derivative has been isolated from Seimatosporium sp., in addition to four known compounds viz.,2-hydroxymethyl-4β,5α,6β-trihydroxycyclohex-2-enone（2）,（-）-phyllostine（3）,（＋）-epiepoxydon（4） and（＋）-epoxydon monoacetate（5）.Similarly one new benzoic acid derivative,named colletonoic acid（6） was isolated from the ethyl acetate fraction of colletotrichum *** structures of the new compounds were elucidated by detailed ^1 H NMR,^13c NMR,cOSY,*** spectroscopic analysis,and *** acid（1）was also isolated from another taxonomical unidentified fungal strain 4295 in *** structures of the known compounds were elucidated by their spectral data comparison to literature *** studies showed that colletonoic acid（6） showed good antibacterial,antifungal,and antialgal activities.

关键词： Seimatosporium sp. colletotrichum sp. Activity Natural product

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A simple criterion for finite time stability with application to impacted buckling of elastic columns

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Applied Mathematics and Mechanics(English Edition) 2018年第3期39卷 305-316页

作者： c.Q.RU Department of Mechanical Engineering University of Alberta

The existing theories of finite-time stability depend on a prescribed bound on initial disturbances and a prescribed threshold for allowable responses. It remains a challenge to identify the critical value of loading parameter for finite time instability observed in experiments without the need of specifying any prescribed threshold for al- lowable responses. Based on an energy balance analysis of a simple dynamic system, this paper proposes a general criterion for finite time stability which indicates that finite time stability of a linear dynamic system with constant coefficients during a given time interval [0, tf] is guaranteed provided the product of its maximum growth rate （determined by the maximum eigen-root pl 〉0） and the duration tf does not exceed 2, i.e., pltf 〈2. The proposed criterion （pltf=2） is applied to several problems of impacted buckling of elastic columns：（i） an elastic column impacted by a striking mass, （ii） longitudinal impact of an elastic column on a rigid wall, and （iii） an elastic column compressed at a constant speed （＂Hoff problem＂）, in which the time-varying axial force is replaced approximately by its average value over the time duration. comparison of critical parameters predicted by the proposed criterion with available experimental and simulation data shows that the proposed criterion is in robust reasonable agreement with the known data, which suggests that the proposed simple criterion （pltf---2） can be used to estimate critical parameters for finite time stability of dynamic systems governed by linear equations with constant coefficients.

关键词： finite time stability, buckling impact, elastic column, Hoff problem, dy-namic buckling, stability criterion

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Allelopathic effect of Acorus tatarinowii upon algae

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Journal of Environmental Sciences 2001年第4期13卷 481-484页

作者： He, c.-q. Wang, c.-k. Dept. of Environmental Science/Eng. Shanghai University Shanghai 200072 China

Besides competing with algae for light and mineral nutrients (i. e. N, P, etc.), the root system of Acorus tatarinowii excretes some chemical substances, which injure and eliminate alga cells, to inhibit the growth of the algae. When the algae cells were treated in 'A. tatarinowii water', some of the chlorophyll a were destroyed and the photosynthetic rate of algae decreased markedly and the ability of alga cells to deoxidize triphenyltetrazolium chloride (TTc) reduced greatly. Then alga cells turned from bright red to bluish green under fluorescence microscope. These showed that the allelopathic effects of A. tatarinowii on algae were obvious and planting A. tatarinowii can control some green algae. The experiment on the extractions of the secretions of the root system showed that the inhibitory effect had a concentration effect. If the concentration of the root secretion was below 30 μl/disc, the inhibitory rate was negative; if it was over 45 μl/disc, the inhibitory rate was positive. This proved that the influence of the root secretion on the same acceptor was a kind of concentration effect. When the concentration of the root secretion was low, it promoted the growth of algae; when the concentration reached a definite threshold value, it restrained the growth of algae. In present case, the threshold value was between 30 μl/disc and 45 μl/disc.

关键词： Algae cells chlorophyll concentration (process) Deoxidants Photosynthesis

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Illustrated Idioms

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英语学习 2002年第3期 27-27页

作者： c.root & K.Blanchard

nosy-overly curious about the affairs of others⊙My neighbor is very *** is always askingme personal questions that I don’t want ***-sensible and calm⊙Helena is a Ievelheaded *** never doesanything foolish.a blue-co... 详细信息

关键词： Illustrated Idioms

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Effect of different water supply on morphology, growth and physiological characteristics of Salix psammophila seedlings in Maowusu sandland, china

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Journal of Environmental Sciences 2001年第4期13卷 411-417页

作者： Xiao, c.-W. Lab. Quantitative Vegetation Ecol. Institute of Botany Chinese Academy of Sciences Beijing 100093 China

Response pattern was investigated for seedlings of Salix psammophila, a dominant shrub in Maowusu sandland, to the simulated precipitation change by artificially controlling water supply at four levels. The growth characters, in terms of plant height, stem diameter, total branch number, total leaf number and area, total bifurcation ratio, total branch lenght and branch number, branch lenght, leaf number and leaf area of each branch order, and leaf, branch and root biomass significantly increased when water supply increased. That water supply had significant effect on biomass allocation showed different investment pattern of biomass resource of the seedlings grown under different water supply treatments. Stomatal density of abaxial leaf surface decreased, and stomatal apparatus length and width of adaxial and abaxial leaf surface increased with the increase of water supply, while Stomatal density of adaxial leaf surface was not affected by water supply. Water supply obviously affected the diumal changes of photosynthetic rate, and the photosynthetic rate of the seedlings showed strongly midday depression grown under the 157.5 mm water supply, but not grown under higher water supply. Additionally the assimilation-light response curves and flourescence efficiency more showed that water supply improve photosynthesis capacity. Finally, S. psammophila seedlings stood out by their slow growth and relatively high investments in root growth in order to reduce tissue losing rate and consumption of water resource for keeping water balance under water stress. The seedlings that grown under rich water supply did by their fast growth and relatively high investments in branch and leaf growth in order to improve the power of capturing light energy for higher photosynthesis.

关键词： Biomass Fluorescence Morphology Photosynthesis Physiology Plants (botany) Precipitation (chemical) Seed Tissue

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Illustrated Idioms

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英语学习 2002年第2期 64-64页

作者： c.root K.Blanchard

a white-collar worker-professional, someone whoworks in an office (usually refersto the middle and upper class)⊙ Harris is a computerprogrammer. He is a white-collar *** (my)time-to avoidhurrying⊙I have to make an i...

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Transcriptome analysis of sugar beet root maggot （Tetanops myopaeformis） genes modulated by the Beta vulgaris host

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Insect Science 2018年第2期25卷 222-234页

作者： Haiyan Li Ann c. Smigocki USDA-ARS Molecular Plant Pathology Laboratory Beltsville Maryland US

Sugar beet root maggot （SBRM, Tetanops myopaeformis von R6der） is a major but poorly understood insect pest of sugar beet （Beta vulgaris L.）. The molecular mecha- nisms underlying plant defense responses are well documented, however, little information is available about complementary mechanisms for insect adaptive responses to overcome host resistance. To date, no studies have been published on SBRM gene expression pro- filing. Suppressive subtractive hybridization （SSH） generated more than 300 SBRM ESTs differentially expressed in the interaction of the pest with a moderately resistant （F1016） and a susceptible （F1010） sugar beet line. Blast2GO v. 3.2 search indicated that over 40% of the differentially expressed genes had known functions, primarily driven by fruit fly D. melanogaster genes. Expression patterns of 18 selected EST clones were confirmed by RT-PcR analysis. Gene Ontology （GO） analysis predicted a dominance of metabolic and catalytic genes involved in the interaction of SBRM with its host. SBRM genes function- ing during development, regulation, cellular process, signaling and under stress conditions were annotated. SBRM genes that were common or unique in response to resistant or susceptible interactions with the host were identified and their possible roles in insect responses to the host are discussed.

关键词： Beta vulgaris resistant sugar beet root maggot suppressive subtractivehybridization susceptible transcriptome

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The role of rhizobacteria in rice plants: Growth and mitigation of toxicity

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Journal of Integrative Agriculture 2018年第12期17卷 2636-2647页

作者： Marcela c F Rêgo Aline F cardoso Thayná da c Ferreira Marta c c de Filippi Telma F V Batista Rafael G Viana Gisele B da Silva Plant Protection Laboratory Institute of Agrarian Sciences Federal Rural University of Amazon Phytopathology Laboratory Brazilian Enterprise for Agricultural Research-Rice and Beans

Allelopathic compounds reduce the growth and productivity of upland rice plants, especially in consecutive plantations. The rhizobacteria Pseudomonas fluorescens BRM-32111 and Burkholderia pyrrocinia BRM-32113 have been recorded as growth promoters in rice. This study was developed to understand the effect of the application of rhizobacteria on upland rice plants in consecutive plantations. Experiments were conducted in a completely randomized design with four replications of four treatments: rice seed inoculated with P. fluorescens BRM-32111, rice seed inoculated with B. pyrrocinia BRM-32113(both sown on soil with rice residue), non-inoculated plants sown on soil with rice residue(control with residue(WR)), and non-inoculated plants on soil with no residue(NR). roots and seedling growth were adversely affected by allelopathic compounds in control WR plants. Plants inoculated with rhizobacteria P. fluorescens BRM-32111 or B. pyrrocinia BRM-32113 induced an increase of 88% in biomass, 3% in the leaf area, 40% in length, 67% in root biomass, 21% in chlorophyll a, 53% in chlorophyll(a+b), 50% in rate of carbon assimilation(A), 227% in A/rubisco carboxylation efficiency(ci) and 63% in water use efficiency(WUE) compared to control WR plants. These results indicate that rhizobacteria P. fluorescens BRM-32111 and B. pyrrocinia BRM-32113 increase the tolerance of rice plants to stress from allelochemicals. There are possible practical agricultural applications of these results for mitigating the effects of environmental allelochemistry on upland rice.

关键词： allelopathy B.pyrrocinia P.fluorescens rhizobacteria rice

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Machine learning prediction of magnetic properties of Fe-based metallic glasses considering glass forming ability

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Journal of Materials Science & Technology 2022年第8期103卷 113-120页

作者： Xin Li Guangcun Shan c.H.Shek School of Instrumentation Science and Opto-electronics Engineering Beihang UniversityBeijing 100191China Department of Materials Science and Engineering City University of Hong KongKowloon TongHong Kong SARChina

Fe-based metallic glasses(MGs)have shown great commercial values due to their excellent soft magnetic *** prediction with consideration of glass forming ability(GFA)is of great signifi-cance for developing novel functional Fe-based ***,theories or models established based on condensed matter physics exhibit limited accuracy and some *** this work,based on 618 Fe-based MGs samples collected from published works,machine learning(ML)models were well trained to predict saturated magnetization(B_(s))of Fe-based *** was treated as a feature using the experimental data of the supercooled liquid region(△T_(x)).Three ML algorithms,namely eXtreme gradient boosting(XGBoost),artificial neural networks(ANN)and random forest(RF),were *** feature selection and hyperparameter tuning,XGBoost showed the best predictive performance on the randomly split test dataset with determination coefficient(R^(2))of 0.942,mean absolute percent error(MAPE)of 5.563%,and root mean squared error(RMSE)of 0.078 T.A variety of feature importance rankings derived by XGBoost models showed that T_(x) played an important role in the predictive performance of the *** work showed the proposed ML method can simultaneously aggregate GFA and other features in ther-modynamics,kinetics and structures to predict the magnetic properties of Fe-based MGs with excellent accuracy.

关键词： Metallic glasses Soft magnetic properties Glass forming ability Machine learning Non-linear regression

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