110,217 research outputs found

    Seasonal Shoot-Feeding by \u3ci\u3eTomicus Piniperda\u3c/i\u3e (Coleoptera: Scolytidae) in Michigan

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    Seasonal shoot-feeding by Tomicus piniperda (L.) was monitored at 2­ week intervals on 15 Scotch pine, Pinus sylvestris L., trees from 8 April through 16 November 1994 in southern Michigan. All shoots that showed evidence of T. piniperda attack were removed every two weeks. In 1994, initial spring flight of T. piniperda began on 22 March. At least two live T. piniperda adults were found on the 15 trees on each sampling date from 8 April through 1 November 1994. In addition, at least one freshly attacked, beetle- free shoot was found on each sampling date except for 1 November. The greatest numbers of newly attacked shoots, with or without adults present, were found from mid-June through mid-August. All adults found in April and May were likely parent adults, while those from June onward were primarily brood adults. Therefore, at all times of the year, live T. piniperda adults can be found on live pine trees, either feeding in the shoots or overwintering at the base of the trunk. Implications of these findings are provided in light of the US federal quarantine on T. piniperda

    CHARACTER ASSESSMENT, GENUS LEVEL BOUNDARIES, AND PHYLOGENETIC ANALYSES OF THE FAMILY RHACOPHORIDAE:: A REVIEW AND PRESENT DAY STATUS

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    The first comprehensive phylogenetic analysis of the family Rhacophoridae was conducted by Liem (1970) scoring 81 species for 36 morphological characters. Channing (1989), in a reanalysis of Liem’s study, produced a phylogenetic hypothesis different from that of Liem. We compared the two studies and produced a third phylogenetic hypothesis based on the same characters. We also present the synapomorphic characters from Liem that define the major clades and each genus within the family. Finally, we summarize intergeneric relationships within the family as hypothesized by other studies, and the family’s current status as it relates to other ranoid families

    Sugar Maple Borer (Coleoptera: Cerambycidae) Activity Associated With Periods of Severe Defoliation

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    A perusal of previous research on sugar maple borer, Glycobius speciosus, in northern New York State strongly associates severe early and late season defoliation with increased borer damage. This re-examination of earlier work suggests foliage protection may be necessary when forest management objectives are concerned with wood volume and quality

    Acoustic properties of fine‐grained sediments from Emerald Basin: Toward an inversion for physical properties using the Biot–Stoll model

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    Acoustic data from two long cores, comprising marine clays and silts taken from Emerald Basin off Nova Scotia, are presented. High‐resolution measurements of compressional wavevelocity,attenuation, and power law exponent are made using ultrasonic frequencies between 100 to 1000 kHz. The observed values of the frequency dependence of attenuation suggest that a nonconstant Q mechanism is needed to explain these data, and Biot–Stoll theory is used to model the experimental results. An inversion scheme is used to constrain physical parameters in the Biot–Stoll dispersion relation. The inversion shows that there is a restricted range of permeability and grain size. By assigning reasonable values for grain size in the inversion, the Biot–Stoll model predicts unique values for the permeability and frame bulk modulus that agree well with estimates made by other means

    Explanation and Cognition

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    These essays draw on work in the history and philosophy of science, the philosophy of mind and language, the development of concepts in children, conceptual.

    From Stochastic Mixability to Fast Rates

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    Empirical risk minimization (ERM) is a fundamental learning rule for statistical learning problems where the data is generated according to some unknown distribution P\mathsf{P} and returns a hypothesis ff chosen from a fixed class F\mathcal{F} with small loss \ell. In the parametric setting, depending upon (,F,P)(\ell, \mathcal{F},\mathsf{P}) ERM can have slow (1/n)(1/\sqrt{n}) or fast (1/n)(1/n) rates of convergence of the excess risk as a function of the sample size nn. There exist several results that give sufficient conditions for fast rates in terms of joint properties of \ell, F\mathcal{F}, and P\mathsf{P}, such as the margin condition and the Bernstein condition. In the non-statistical prediction with expert advice setting, there is an analogous slow and fast rate phenomenon, and it is entirely characterized in terms of the mixability of the loss \ell (there being no role there for F\mathcal{F} or P\mathsf{P}). The notion of stochastic mixability builds a bridge between these two models of learning, reducing to classical mixability in a special case. The present paper presents a direct proof of fast rates for ERM in terms of stochastic mixability of (,F,P)(\ell,\mathcal{F}, \mathsf{P}), and in so doing provides new insight into the fast-rates phenomenon. The proof exploits an old result of Kemperman on the solution to the general moment problem. We also show a partial converse that suggests a characterization of fast rates for ERM in terms of stochastic mixability is possible.Comment: 21 pages, accepted to NIPS 201

    Deinstitutionalization as a Function of Interagency Planning: A Case Study

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