Patrol rifle program

Examines the advantages and disadvantages of a department's having a comprehensive patrol rifle program

Text Organiztion and Structure in Science Textbooks

This study examined the text organization and structure of fourth and sixth grade science textbooks. This included prereading questions, advance organizers, margin notes, and type of text structure. In addition, chapter activities were classified as to the degree of problem solving skills developed by ranking the activities according to Bloom\u27s (1956) taxonomy of cognitive skills

Effect of Cultivar on Chlorophyll Meter and Canopy Reflectance Measurements in Cucumber

Optical sensors can be used to assess crop N status to assist with N fertilizer management. Differences between cultivars may affect optical sensor measurement. Cultivar effects on measurements made with the SPAD-502 (Soil Plant Analysis Development) meter and the MC-100 (Chlorophyll Concentration Meter), and of several vegetation indices measured with the Crop Circle ACS470 canopy reflectance sensor, were assessed. A cucumber (Cucumis sativus L.) crop was grown in a greenhouse, with three cultivars. Each cultivar received three N treatments, of increasing N concentration, being deficient (N1), sufficient (N2) and excessive (N3). There were significant differences between cultivars in the measurements made with both chlorophyll meters, particularly when N supply was sufficient and excessive (N2 and N3 treatments, respectively). There were no consistent differences between cultivars in vegetation indices. Optical sensor measurements were strongly linearly related to leaf N content in each of the three cultivars. The lack of a consistent effect of cultivar on the relationship with leaf N content suggests that a unique equation to estimate leaf N content from vegetation indices can be applied to all three cultivars. Results of chlorophyll meter measurements suggest that care should be taken when using sufficiency values, determined for a particular cultiva

The Cerebellum: A Neural System for the Study of Reinforcement Learning

In its strictest application, the term “reinforcement learning” refers to a computational approach to learning in which an agent (often a machine) interacts with a mutable environment to maximize reward through trial and error. The approach borrows essentials from several fields, most notably Computer Science, Behavioral Neuroscience, and Psychology. At the most basic level, a neural system capable of mediating reinforcement learning must be able to acquire sensory information about the external environment and internal milieu (either directly or through connectivities with other brain regions), must be able to select a behavior to be executed, and must be capable of providing evaluative feedback about the success of that behavior. Given that Psychology informs us that reinforcers, both positive and negative, are stimuli or consequences that increase the probability that the immediately antecedent behavior will be repeated and that reinforcer strength or viability is modulated by the organism's past experience with the reinforcer, its affect, and even the state of its muscles (e.g., eyes open or closed); it is the case that any neural system that supports reinforcement learning must also be sensitive to these same considerations. Once learning is established, such a neural system must finally be able to maintain continued response expression and prevent response drift. In this report, we examine both historical and recent evidence that the cerebellum satisfies all of these requirements. While we report evidence from a variety of learning paradigms, the majority of our discussion will focus on classical conditioning of the rabbit eye blink response as an ideal model system for the study of reinforcement and reinforcement learning

Evaluation of rations used in performance testing of bulls and steers

Cover title.Includes bibliographical references

The Use of Chlorophyll Meters to Assess Crop N Status and Derivation of Sufficiency Values for Sweet Pepper

Chlorophyll meters are promising tools for improving the nitrogen (N) management of vegetable crops. To facilitate on-farm use of these meters, sufficiency values that identify deficient and sufficient crop N status are required. This work evaluated the ability of three chlorophyll meters (SPAD-502, atLEAF+, and MC-100) to assess crop N status in sweet pepper. It also determined sufficiency values for optimal N nutrition for each meter for pepper. The experimental work was conducted in a greenhouse, in Almería, Spain, very similar to those used for commercial production, in three different crops grown with fertigation. In each crop, there were five treatments of different N concentration in the nutrient solution, applied in each irrigation, ranging from a very deficient to very excessive N supply. In general, chlorophyll meter measurements were strongly related to crop N status in all phenological stages of the three crops, indicating that these measurements are good indicators of the crop N status of pepper. Sufficiency values determined for each meter for the four major phenological stages were consistent between the three crops. This demonstrated the potential for using these meters with sufficiency values to improve the N management of commercial sweet pepper crops

Validity of Mixed 2D and 3D Cadastral Parcels in the Land Administration Domain Model

SUMMARY The Land Administration Domain Model (ISO 19152) (ISO-TC211 2012) defines a specific geometry form which allows the clean and simple mixing of 3D cadastral objects such as volumetric parcels with the more common 2D parcels. It does this by introducing a concept of boundary surfaces, known as "face strings". The unbounded nature in the vertical direction of the "face strings" corresponds to the unbounded nature of 2D parcels, that is, they comprise the boundaries of infinite 3D columns of space (see ISO-TC211 201

Microstructure, Elastic and Inelastic Properties of Partially Graphitized Biomorphic Carbons

The microstructural characteristics and amplitude dependences of the Young’s modulus E and internal friction (logarithmic decrement δ) of biocarbon matrices prepared by beech wood carbonization at temperatures Tcarb = 850–1600°C in the presence of a nickelcontaining catalyst have been studied. Using Xray diffraction and electron microscopy, it has been shown that the use of a nickel catalyst during carbon ization results in a partial graphitization of biocarbons at Tcarb ≥ 1000°C: the graphite phase is formed as 50 to 100nm globules at Tcarb = 1000°C and as 0.5 to 3.0μm globules at Tcarb = 1600°C. It has been found that the measured dependences E(Tcarb) and δ(Tcarb) contain three characteristic ranges of variations in the Young’s modulus and logarithmic decrement with a change in the carbonization temperature: E increases and δ decreases in the ranges Tcarb 1300°C; in the range 1000 < Tcarb < 1300°C, E sharply decreases and δ increases. The observed behavior of E(Tcarb) and δ(Tcarb) for biocarbons carbonized in the presence of nickel correlates with the evolution of their microstructure. The largest values of E are obtained for samples with Tcarb = 1000 and 1600°C. However, the samples with Tcarb = 1600°C exhibit a higher suscep tibility to microplasticity due to the presence of a globular graphite phase that is significantly larger in size and total volume.Peer reviewe

cAMP-mediated secretion of brain-derived neurotrophic factor in developing airway smooth muscle

AbstractModerate hyperoxic exposure in preterm infants contributes to subsequent airway dysfunction and to risk of developing recurrent wheeze and asthma. The regulatory mechanisms that can contribute to hyperoxia-induced airway dysfunction are still under investigation. Recent studies in mice show that hyperoxia increases brain-derived neurotrophic factor (BDNF), a growth factor that increases airway smooth muscle (ASM) proliferation and contractility. We assessed the mechanisms underlying effects of moderate hyperoxia (50% O2) on BDNF expression and secretion in developing human ASM. Hyperoxia increased BDNF secretion, but did not alter endogenous BDNF mRNA or intracellular protein levels. Exposure to hyperoxia significantly increased [Ca2+]i responses to histamine, an effect blunted by the BDNF chelator TrkB-Fc. Hyperoxia also increased ASM cAMP levels, associated with reduced PDE4 activity, but did not alter protein kinase A (PKA) activity or adenylyl cyclase mRNA levels. However, 50% O2 increased expression of Epac2, which is activated by cAMP and can regulate protein secretion. Silencing RNA studies indicated that Epac2, but not Epac1, is important for hyperoxia-induced BDNF secretion, while PKA inhibition did not influence BDNF secretion. In turn, BDNF had autocrine effects of enhancing ASM cAMP levels, an effect inhibited by TrkB and BDNF siRNAs. Together, these novel studies suggest that hyperoxia can modulate BDNF secretion, via cAMP-mediated Epac2 activation in ASM, resulting in a positive feedback effect of BDNF-mediated elevation in cAMP levels. The potential functional role of this pathway is to sustain BDNF secretion following hyperoxic stimulus, leading to enhanced ASM contractility and proliferation