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Author (up) Ashraf, M.; Habib-ur-Rehman,
Title Interactive effects of nitrate and long-term waterlogging on growth, water relations, and gaseous exchange properties of maize (Zea mays L.) Type Journal Article
Year 1999 Publication Plant Science Abbreviated Journal Plant Science
Volume 144 Issue 1 Pages 35-43
Keywords Growth; Chlorophyll contents; Maize; Net assimilation; Stomatal conductance; Waterlogging
Abstract The interactive effect of additional amount of NO3-N and long-term waterlogging on maize was studied in glasshouse conditions. Forty-two-day-old plants were subjected to continuous flooding for 21 days at three different NO3-N regimes (196, 294 and 392 mg N kg−1 soil). Shoot fresh mass and leaf area of waterlogged plants reduced significantly at two higher NO3 regimes. Leaf water potential was generally decreased, whereas osmotic potential increased in all waterlogged plants but much reduction in leaf water potential was found at the highest external NO3 regime. Leaf turgor potential decreased due to waterlogging but this decrease progressed with increase in external NO3 concentration. Chlorophylls ‘a’ and ‘b’ increased in non-waterlogged plants with increase in NO3 concentration of the growth medium, but these two pigments decreased significantly due to waterlogging particularly at the two higher NO3 regimes. Chlorophyll a/b ratio increased linearly in non-waterlogged plants with increase in external NO3 regimes but the ratio remained almost unchanged due to waterlogging. Waterlogging caused a reduction in net photosynthesis and stomatal conductance but no effect of additional amount of NO3 was observed on these two variables. Transpiration was also decreased as a result of waterlogging but a marked reduction in this variable was observed at the highest external NO3 concentration. Water-use efficiency increased with increase in external NO3 concentration in both waterlogged and non-waterlogged plants. Although waterlogging caused a reduction in substomatal CO2 concentration, it generally increased in both waterlogged and non-waterlogged plants due to supplementary NO3, particularly at its highest concentration. From these results, it is clear that supplementary NO3 in the growth medium of maize plants experiencing long-term waterlogging had injurious effect on growth.
Call Number Serial 618
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Author (up) Barnett, R.C.; Brennan, R.T.; Gareis, K.C.
Title A Closer Look at the Measurement of Burnout Type Journal Article
Year 1999 Publication Journal of Applied Biobehavioral Research Abbreviated Journal J Appl Biobehav Res
Volume 4 Issue 2 Pages 65-78
Keywords Burnout; Emotional exhaustion; Professional efficacy; Cynicism; Maslach Burnout Inventory
Abstract Burnout, a widely studied syndrome, has been defined as comprising three factorially distinct symptoms: emotional exhaustion, decreased sense of professional efficacy, and cynicism. The most common measure is the Maslach Burnout Inventory (MBI; Maslach, Jackson, & Leiter, 1996). We identified and corrected two flaws in the MBI, namely: (a) items purport to assess feelings, but half do not directly concern feelings; and (b) response categories are not mutually exclusive, rendering results difficult to interpret and inflating measurement error. The revised and original scales are highly correlated and have similar factor structures, interfactor correlation patterns, reliability, and construct-related evidence of validity. The revised scale corrects flaws in the original while retaining its strengths and should, therefore, be used in future studies.
Call Number Serial 738
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Author (up) Battista, J.R.; Earl, A.M.; Park, M.J.
Title Why is Deinococcus radiodurans so resistant to ionizing radiation? Type Journal Article
Year 1999 Publication Trends in Microbiology Abbreviated Journal Trends Microbiol
Volume 7 Issue 9 Pages 362-365
Keywords DNA Damage; DNA Replication; DNA, Bacterial/metabolism; *Gamma Rays; Genome, Bacterial; Gram-Positive Cocci/genetics/growth & development/*radiation effects; *Radiation Tolerance; Recombination, Genetic
Abstract When exponential-phase cultures of Deinococcus radiodurans are exposed to a 5000-Gray dose of gamma radiation, individual cells suffer massive DNA damage. Despite this insult to their genetic integrity, these cells survive without loss of viability or evidence of mutation, repairing the damage by as-yet-poorly-understood mechanisms.
Call Number Serial 1020
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Author (up) Baylis, H.A.; Furuichi, T.; Yoshikawa, F.; Mikoshiba, K.; Sattelle, D.B.
Title Inositol 1,4,5-trisphosphate receptors are strongly expressed in the nervous system, pharynx, intestine, gonad and excretory cell of Caenorhabditis elegans and are encoded by a single gene (itr-1) Type Journal Article
Year 1999 Publication Journal of Molecular Biology Abbreviated Journal J Mol Biol
Volume 294 Issue 2 Pages 467-476
Keywords Amino Acid Sequence; Animals; Animals, Genetically Modified; Binding Sites; Caenorhabditis elegans/*genetics; Calcium Channels/*genetics/*metabolism; Cell Membrane/genetics/metabolism; Conserved Sequence; Gene Expression Profiling; Gonads/metabolism; Helminth Proteins/*genetics/*metabolism; Inositol 1,4,5-Trisphosphate Receptors; Intestines/metabolism; Molecular Sequence Data; Nervous System/metabolism; Pharynx/metabolism; RNA, Messenger; Receptors, Cytoplasmic and Nuclear/*genetics/*metabolism; Rectum/cytology/metabolism
Abstract Inositol 1,4,5-trisphosphate (InsP3) activates receptors (InsP3Rs) that mediate intracellular Ca(2+ )release, thereby modulating intracellular calcium signals and regulating important aspects of cellular physiology and gene expression. To further our understanding of InsP3Rs we have characterised InsP3Rs and the InsP3R gene, itr-1, from the model organism Caenorhabditis elegans. cDNAs encoding InsP3Rs were cloned enabling us to: (a) identify three putative transcription start sites that result in alternative mRNA 5' ends: (b) detect alternative splicing at three sites and: (c) determine the full genomic organisation of the itr-1 gene. The InsP3R protein (ITR-1) is approximately 42 % identical with known InsP3Rs and possesses conserved structural features. When the putative InsP3 binding domain was expressed in Escherichia coli, specific binding of InsP3 was detected. Using antibodies against ITR-1 we detected a protein of 220 kDa in C. elegans membranes. These antibodies and itr-1::GFP (green fluorescent protein) reporter constructs were used to determine the expression pattern of itr-1 in C. elegans. Strong expression was observed in the intestine, pharynx, nerve ring, excretory cell and gonad. These results demonstrate the high degree of structural and functional conservation of InsP3Rs from nematodes to mammals and the utility of C. elegans as a system for studies on InsP3R mediated signalling.
Call Number Serial 309
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Author (up) Brackett, R.E.
Title Incidence, contributing factors, and control of bacterial pathogens in produce Type Journal Article
Year 1999 Publication Postharvest Biology and Technology Abbreviated Journal Postharvest Biology and Technology
Volume 15 Issue 3 Pages 305-311. *Strategian Select*
Keywords Fresh produce; Food safety; Bacterial pathogens; Food poisoning
Abstract The importance of bacterial pathogens in the transmission of foodborne illness has become apparent in recent years. Several large, well-publicized outbreaks of foodborne illness have been linked to cantaloupe, tomatoes, lettuce, alfalfa sprouts, and both apple and orange juices. In addition, numerous other smaller scale outbreaks linked to these and other commodities have also been reported. Although contributing factors have not been determined in all cases, several notable causes have been proposed. In particular, cross contamination with fecal matter of both domestic as well as wild animals have been suggested. In addition, contact with contaminated water has also been identified as a source of contamination. However, the use of untreated manure or sewage, lack of field sanitation, poorly or unsanitized transportation vehicles, and contamination by handlers are also suggested as potential contributing factors. Control of foodborne pathogens in produce must begin before produce is even planted by avoiding fields which have been subjected to flooding, on which animals have been recently grazed, or have otherwise been contaminated with manure. After planting, only clean potable water should be used for irrigation and harvesting equipment should be thoroughly cleaned and sanitized. Both field workers and packinghouse and processing plant personnel should be instructed in proper personal hygiene and provided with adequate sanitary and handwashing facilities. Vehicles transporting finished products should be sanitized, properly loaded to provide adequate air circulation, and maintained at proper temperatures. Likewise, retail display cases must be kept clean and at proper refrigeration temperatures. Finally, consumers should be informed as to proper handling of produce, particularly in the case of new generation products such as modified atmosphere packaged produce.
Call Number Serial 1673
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Author (up) Cassell, J.; McNeill, D.; McCullough, K.-E.
Title Speech-gesture mismatches: Evidence for one underlying representation of linguistic and nonlinguistic information Type Journal Article
Year 1999 Publication Pragmatics and Cognition Abbreviated Journal P&C
Volume 7 Issue 1 Pages 1-34
Abstract Adults and children spontaneously produce gestures while they speak, and such gestures appear to support and expand on the information communicated by the verbal channel. Little research, however, has been carried out to examine the role played by gesture in the listener's representation of accumulating information. Do listeners attend to the gestures that accompany narrative speech? In what kinds of relationships between gesture and speech do listeners attend to the gestural channel? If listeners do attend to information received in gesture, how is this information represented— is it 'tagged' as originating in the gestural channel? In this article research is described that addresses these questions. Results show that listeners do attend to information conveyed in gesture, when that information supplements or even contradicts the information conveyed by speech. And information received via gesture is available for retelling in speech. These results are taken to demonstrate that gesture is not taken by the listener to be epiphenomenal to the act of speaking, or a simple manual translation of speech. But they also suggest that the information conveyed in a discourse may be represented in a manner that is neither gesture nor language, although accessible to both channels.

Subject Headings: Speech; Gesture; Linguistic

Keywords: Speech-gesture mismatches: Evidence for one underlying representation of linguistic and nonlinguistic information
Call Number Serial 2660
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Author (up) Crider, M.E.; Cooper, R.L.
Title Importance of stimulation paradigm in determining facilitation and effects of neuromodulation Type Journal Article
Year 1999 Publication Brain Research Abbreviated Journal Brain Res
Volume 842 Issue 2 Pages 324-331
Keywords Animals; Astacoidea; Axons/*physiology; Electric Stimulation; Electromyography; Evoked Potentials; In Vitro Techniques; Membrane Potentials; Muscle, Skeletal/innervation/physiology; Nerve Endings/physiology; Neuromuscular Junction/*physiology; Synaptic Transmission/physiology
Abstract Evoked synaptic activity within the CNS and at the neuromuscular junction in most in vivo preparations studied occurs not with single isolated stimuli, but with trains, or bursts, of stimuli. Although for ease in studying the mechanisms of vesicular synaptic transmission one often uses single discrete stimuli, the true mechanisms in the animal may be far more complex. When repetitive stimuli are present at a nerve terminal, often a heightened (i.e., facilitated) postsynaptic potential can be as a result. Facilitation is commonly used as an index of synaptic function and plasticity induced by chronic stimulation or by neuromodulation. The mechanisms that give rise to facilitation are thought to be the same that may underlie short-term learning and memory [C.H. Bailey, E.R. Kandel, Structural changes accompanying memory storage. Annu. Rev. Physiol. 55 (1993) 397-426.]. Differences in short term facilitation (STF) are seen depending on the conventional stimulation paradigm (twin pulse, train, or continuous) used to induce facilitation. Thus, a battery of paradigms should be used to characterize synaptic function to obtain a closer understanding of the possible in vivo conditions.
Call Number Serial 1593
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Author (up) Davidson; Irwin
Title The functional neuroanatomy of emotion and affective style Type Journal Article
Year 1999 Publication Trends in Cognitive Sciences Abbreviated Journal Trends Cogn Sci
Volume 3 Issue 1 Pages 11-21
Keywords Emotion; Brain function; Neuroimaging; Prefrontal cortex; Amygdala; Neuroscience; Review
Abstract Recently, there has been a convergence in lesion and neuroimaging data in the identification of circuits underlying positive and negative emotion in the human brain. Emphasis is placed on the prefrontal cortex (PFC) and the amygdala as two key components of this circuitry. Emotion guides action and organizes behavior towards salient goals. To accomplish this, it is essential that the organism have a means of representing affect in the absence of immediate elicitors. It is proposed that the PFC plays a crucial role in affective working memory. The ventromedial sector of the PFC is most directly involved in the representation of elementary positive and negative emotional states while the dorsolateral PFC may be involved in the representation of the goal states towards which these elementary positive and negative states are directed. The amygdala has been consistently identified as playing a crucial role in both the perception of emotional cues and the production of emotional responses, with some evidence suggesting that it is particularly involved with fear-related negative affect. Individual differences in amygdala activation are implicated in dispositional affective styles and increased reactivity to negative incentives. The ventral striatum, anterior cingulate and insular cortex also provide unique contributions to emotional processing.
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Author (up) Elliott, D.; Binsted, G.; Heath, M.
Title The control of goal-directed limb movements: Correcting errors in the trajectory Type Journal Article
Year 1999 Publication Human Movement Science Abbreviated Journal Human Movement Science
Volume 18 Issue 2-3 Pages 121-136
Abstract A number of recent models of limb control have attempted to explain speed-accuracy trade-off in goal-directed movements on the basis of the characteristics of the muscular impulses that are specified prior to movement initiation. In contrast, studies from our laboratory have demonstrated that, even for very rapid aiming movements, the characteristics of the movement trajectory change with the availability of visual information about the position of the limb and the target during the movement. Moreover, when the movement of the limb is perturbed at movement initiation by an electromagnetic force, performers can rapidly adjust their aiming movements in order to hit the target if visual feedback is available. The performer can also rapidly adjust to unexpected changes in target size and amplitude. Visually based adjustments to the movement trajectory can be either discrete or continuous.

Subject Headings: Vision; Motor control; Speed-accuracy

Keywords: The control of goal-directed limb movements: Correcting errors in the trajectory
Call Number Serial 2781
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Author (up) Elliott, K.J.; L. Hendrick, R.; Major, A.E.; Vose, J.M.; Swank, W.T.
Title Vegetation dynamics after a prescribed fire in the southern Appalachians Type Journal Article
Year 1999 Publication Forest Ecology and Management Abbreviated Journal Forest Ecology and Management
Volume 114 Issue 2-3 Pages 199-213
Keywords Pine–oak heath; Restoration; Mortality; Kalmia latifolia; Pinus rigida; Quercusspp.; Herbaceous flora; Diversity; Species nomenclature follows Radford et al. (1968)
Abstract In April 1995, the USDA Forest Service conducted a prescribed burn along with a south-facing slope of southern Appalachian watershed, Nantahala National Forest, western NC. Fire had been excluded for over 70 years and the purpose of the burn was to create a mosaic of fire intensities to restore a degraded pine/hardwood community and to stimulate forage production and promote oak regeneration along a hillslope gradient. Permanent plots were sampled at three locations along a gradient from 1500 to 1700 m. Plot locations corresponded to three community types: mesic, near-riparian cove (low slope); dry, mixed-oak (mid slope); and xeric, pine/hardwood (ridge). Before burning (1994–1995) and post-burn (summer, 1995 and summer, 1996) vegetation measurements were used to determine the effects of fire on the mortality and regeneration of overstory trees, understory shrubs, and herbaceous species. After the burn, mortality was highest (31%) at the ridge location, substantially reducing overstory (from 26.84 pre-burn to 19.05 m2 ha−1 post-burn) and understory shrub (from 6.52 pre-burn to 0.37 m2 ha−1 post-burn) basal area. At the mid-slope position, mortality was only 3%, and no mortality occurred at the low slope. Not surprisingly, percent mortality corresponded to the level of fire intensity. Basal area of Kalmia latifolia, Gaylussacia baccata, and Vaccinium spp. were substantially reduced after the fire, but density increased due to prolific sprouting. The prescribed fire had varying effects on species richness and diversity across the hillslope gradient. On the ridge, diversity was significantly increased in the understory and herb-layer, but decreased in the overstory. On the mid slope, no change was observed in the overstory, but diversity significantly decreased in the understory. On the low slope, no change was observed in the overstory or understory.
Call Number Serial 1765
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