University at Buffalo

About: University at Buffalo is a education organization based out in Buffalo, New York, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 33773 authors who have published 63840 publications receiving 2278954 citations. The organization is also known as: UB & State University of New York at Buffalo.

Three-dimensional reconstruction from projections: a review of algorithms.

Abstract: Publisher Summary This chapter provides an overview of three-dimensional reconstruction from projections. The chapter reviews the algorithms that have been proposed to solve the reconstruction problem. The known reconstruction algorithms are classified into four categories—summation, the use of Fourier transform, analytic solution of the integral equations, and series expansion approaches. For each class of algorithms several points need to be considered—a general intuitive description, a precise mathematical description of a typical reconstruction method of the class, and a brief description of other methods in the class. All algorithms for reconstruction take as input the projection data, and all produce as output an estimate of the original structure based on the available data. The estimate varies from method to method. The relative performance of the various methods depends on the object and how the data are collected. The simplest algorithm for reconstruction is to estimate the density at a point by adding all the ray sums of the rays through that point. The Fourier method depends on transforming the projections into the Fourier space, where they define part of the Fourier transform of the whole object. Each projection may be shown to yield values on a central section of the Fourier space, which is a line or plane through the origin at an angle corresponding to the direction of the projection in real space.

Multi-scale predictions of massive conifer mortality due to chronic temperature rise

Abstract: Research integrating experimental data and modelling to improve representation of plant physiological thresholds infers largely temperature-driven loss of conifer trees by 2100 across the southwestern USA and much of the Northern Hemisphere.

Phonotactics and Syllable Stress: Implications for the Processing of Spoken Nonsense Words:

Abstract: phonotactics Two experiments using bisyllabic CVCCVC nonsense words that varied in phonotactic probability and stress placement were conducted to examine the influences of phonotactic and metrical information on spoken word recognition. Experiment 1 examined participants' intuitions about the phonological "goodness" of nonsense words. Experiment 2 examined processing times for the same stimuli in a speeded auditory repetition task. The results of both studies provide further evidence that the phonotactic configuration and stress placement of spoken stimuli have important implications for the representation and processing of spoken words. syllable stress

Quantification, correlations and manipulations of wound-induced changes in jasmonic acid and nicotine in Nicotiana sylvestris

Abstract: Jasmonic acid (JA) is thought to be part of a signal-transduction pathway which dramatically increases de-novo nicotine synthesis in the roots and increases whole-plant (WP) nicotine pools in response to the wounding of the leaves in Nicotiana sylvestrisSpegazzini and Comes (Solanaceae). We report the synthesis of a doubly labeled JA ([1, 2-13C]JA) and use it as an internal standard to quantify by gas chromatography-mass spectrometry the changes in root and shoot JA pools in plants subjected to differing amounts of standardized leaf wounding. Wounding increased JA pools 10-fold locally in damaged leaves within 90 min and systemically in the roots (3.5-fold) 180 min after wounding. If JA functions as an intermediary between stimulus and response, quantitative relationships among the stimulus, JA, and the response should exist. To examine these relationships, we varied the number of punctures in four leaves and quantified both the resulting JA in damaged leaves after 90 min and the resulting WP nicotine concentration after 5 d. We found statistically significant, positive relationships among number of leaf punctures, endogenous JA, and WP nicotine accumulation. We used two inhibitors of wound-induced nicotine production, methyl salicylate and indole-3-acetic acid, to manipulate the relationships between wound-induced changes in JA and WP nicotine accumulation. Since wounding and the response to wounding occur in widely separated tissues, we applied inhibitors to different plant parts to examine their effects on the local and systemic components of this response. In all experiments, inhibition of the wound-induced increase in leaf JA 90 min after wounding was associated with the inhibition of the nicotine response 5 d after wounding. We conclude that wound-induced increases in leaf JA are an important component of this long-distance signal-transduction pathway.

Cement reinforced with short carbon fibers: a multifunctional material

Abstract: This is a review of cement-matrix composites containing short carbon fibers. These composites exhibit attractive tensile and flexural properties, low drying shrinkage, high specific heat, low thermal conductivity, high electrical conductivity, high corrosion resistance and weak thermoelectric behavior. Moreover, they facilitate the cathodic protection of steel reinforcement in concrete, and have the ability to sense their own strain, damage and temperature. Fiber surface treatment can improve numerous properties of the composites. Conventional carbon fibers of diameter 15 μm are more effective than 0.1 μm diameter carbon filaments as a reinforcement, but are much less effective for radio wave reflection (EMI shielding). Carbon fiber composites are superior to steel fiber composites for strain sensing, but are inferior to steel fiber composites in the thermoelectric behavior.