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Author (up) Amaku, M.; Coutinho, F.A.B.; Massad, E. file  url
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  Title Why dengue and yellow fever coexist in some areas of the world and not in others? Type Journal Article
  Year 2011 Publication Bio Systems Abbreviated Journal Biosystems  
  Volume 106 Issue 2-3 Pages 111-120  
  Keywords Adaptive Immunity/*immunology; Aedes/*virology; Africa/epidemiology; Animals; Asia/epidemiology; Computer Simulation; *Demography; Dengue/*epidemiology/immunology/transmission; Humans; Insect Vectors/*virology; *Models, Biological; South America/epidemiology; Species Specificity; Yellow Fever/*epidemiology/immunology/transmission  
  Abstract Urban yellow fever and dengue coexist in Africa but not in Asia and South America. In this paper, we examine four hypotheses (and various combinations thereof) to explain the absence of yellow fever in urban areas of Asia and South America. In addition, we examine an additional hypothesis that offers an explanation of the coexistence of the infections in Africa while at the same time explaining their lack of coexistence in Asia. The hypotheses we tested to explain the nonexistence of yellow fever in Asia are the following: (1) the Asian Aedes aegypti is relatively incompetent to transmit yellow fever; (2) there would exist a competition between dengue and yellow fever viruses within the mosquitoes, as suggested by in vitro studies in which the dengue virus always wins; (3) when an A. aegypti mosquito that is infected by or latent for yellow fever acquires dengue, it becomes latent for dengue due to internal competition within the mosquito between the two viruses; (4) there is an important cross-immunity between yellow fever and other flaviviruses, dengue in particular, such that a person recovered from a bout of dengue exhibits a diminished susceptibility to yellow fever. This latter hypothesis is referred to below as the “Asian hypothesis.” Finally, we hypothesize that: (5) the coexistence of the infections in Africa is due to the low prevalence of the mosquito Aedes albopictus in Africa, as it competes with A. aegypti. We will refer to this latter hypothesis as the “African hypothesis.” We construct a model of transmission that allows all of the above hypotheses to be tested. We conclude that the Asian and the African hypotheses can explain the observed phenomena, whereas other hypotheses fail to do so.  
  Call Number Serial 1532  
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Author (up) Aveskamp, M.M.; Verkley, G.J.M.; de Gruyter, J.; Murace, M.A.; Perello, A.; Woudenberg, J.H.C.; Groenewald, J.Z.; Crous, P.W. file  url
openurl 
  Title DNA phylogeny reveals polyphyly of Phoma section Peyronellaea and multiple taxonomic novelties Type Journal Article
  Year 2009 Publication Mycologia Abbreviated Journal Mycologia  
  Volume 101 Issue 3 Pages 363-382  
  Keywords Actins/analysis/genetics; Ascomycota/*classification/cytology/genetics; Biodiversity; DNA, Fungal/*analysis/genetics; DNA, Ribosomal Spacer/analysis/genetics; Genetic Speciation; Genetic Variation; Molecular Sequence Data; *Phylogeny; Polymerase Chain Reaction; Sequence Alignment; Sequence Analysis, DNA; Species Specificity; Tubulin/analysis/genetics  
  Abstract Species of the anamorph genus Phoma are commonly isolated from a wide range of ecological niches. They are notoriously difficult to identify due to the paucity of morphological features and the plasticity of these when cultivated on agar media. Species linked to Phoma section Peyronellaea are typified by the production of dictyochlamydospores and thus have additional characters to use in taxon delineation. However, the taxonomy of this section is still not fully understood. Furthermore the production of such chlamydospores also is known in some other sections of Phoma. DNA sequences were generated from three loci, namely ITS, actin, and 3-tubulin, to clarify the phylogeny of Phoma taxa that produce dictyochlamydospores. Results were unable to support section Peyronellaea as a taxonomic entity. Dictyochlamydospore formation appears to be a feature that developed, or was lost, many times during the evolution of Phoma. Furthermore, based on the multigene analyses, five new Phoma species could be delineated while a further five required taxonomic revision to be consistent with the genetic variation observed.  
  Call Number Serial 1999  
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Author (up) Callaway, R.M.; Brooker, R.W.; Choler, P.; Kikvidze, Z.; Lortie, C.J.; Michalet, R.; Paolini, L.; Pugnaire, F.I.; Newingham, B.; Aschehoug, E.T.; Armas, C.; Kikodze, D.; Cook, B.J. file  url
openurl 
  Title Positive interactions among alpine plants increase with stress Type Journal Article
  Year 2002 Publication Nature Abbreviated Journal Nature  
  Volume 417 Issue 6891 Pages 844-848  
  Keywords Atmospheric Pressure; Biomass; *Ecosystem; Geography; Plant Development; *Plant Physiological Phenomena; Reproduction; Species Specificity; Temperature; Stress  
  Abstract Plants can have positive effects on each other. For example, the accumulation of nutrients, provision of shade, amelioration of disturbance, or protection from herbivores by some species can enhance the performance of neighbouring species. Thus the notion that the distributions and abundances of plant species are independent of other species may be inadequate as a theoretical underpinning for understanding species coexistence and diversity. But there have been no large-scale experiments designed to examine the generality of positive interactions in plant communities and their importance relative to competition. Here we show that the biomass, growth and reproduction of alpine plant species are higher when other plants are nearby. In an experiment conducted in subalpine and alpine plant communities with 115 species in 11 different mountain ranges, we find that competition generally, but not exclusively, dominates interactions at lower elevations where conditions are less physically stressful. In contrast, at high elevations where abiotic stress is high the interactions among plants are predominantly positive. Furthermore, across all high and low sites positive interactions are more important at sites with low temperatures in the early summer, but competition prevails at warmer sites.  
  Call Number Serial 2154  
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Author (up) Curtis, A.; Lyons, V.; Fink, G. file  url
openurl 
  Title The human hypothalamic LHRH precursor is the same size as that in rat and mouse hypothalamus Type Journal Article
  Year 1983 Publication Biochemical and Biophysical Research Communications Abbreviated Journal Biochem Biophys Res Commun  
  Volume 117 Issue 3 Pages 872-877  
  Keywords Aged; Animals; Female; Gonadotropin-Releasing Hormone/*biosynthesis; Humans; Hypothalamus/*metabolism; Male; Mice; Molecular Weight; Protein Biosynthesis; Protein Precursors/*isolation & purification; Rats; Species Specificity  
  Abstract The synthesis of the decapeptide luteinizing hormone releasing hormone (LHRH) in human, rat and mouse brain has been investigated by studying the in vitro translation products of Poly A+ mRNA extracts from the hypothalamus. The translation products of all three species contained a single 28000 MW polypeptide which immunoprecipitated with a specific anti-LHRH serum. This polypeptide was not present in the translation products of Poly A+ mRNA extracts from the hypothalamus of the hypogonadal mouse, a mutant strain totally deficient in LHRH. These results show that in the human, rat and normal mouse, LHRH is synthesized as a component of a precursor peptide with a molecular weight of 28000.  
  Call Number Serial 325  
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Author (up) Gatenby, A.A.; Boccara, M.; Baulcombe, D.C.; Rothstein, S.J. file  url
openurl 
  Title Expression of a wheat alpha-amylase gene in Escherichia coli: recognition of the translational initiation site and the signal peptide Type Journal Article
  Year 1986 Publication Gene Abbreviated Journal Gene  
  Volume 45 Issue 1 Pages 11-18  
  Keywords DNA/genetics; Escherichia coli/genetics; Plant Proteins/*biosynthesis/genetics; Protein Biosynthesis; Protein Processing, Post-Translational; Protein Sorting Signals/metabolism; Recombinant Fusion Proteins/*biosynthesis/genetics/secretion; Recombinant Proteins/*biosynthesis; Species Specificity; Triticum/enzymology/genetics; alpha-Amylases/*biosynthesis/genetics/secretion; beta-Lactamases/genetics  
  Abstract Transcription of a full-length cDNA clone of wheat alpha-amylase using a lac promoter in Escherichia coli results in synthesis of a precursor alpha-amylase polypeptide of the correct size, indicating that translation initiates correctly. Recognition of the plant translational initiation site by E. coli ribosomes is 15-20% as efficient as the ribosome-binding site of the beta-lactamase gene when it is fused to alpha-amylase. The alpha-amylase signal peptide is recognised in E. coli resulting in secretion of the enzyme into the periplasmic space; deletion of the signal peptide prevents secretion. Replacement of the alpha-amylase signal peptide with a beta-lactamase signal peptide also enables the bacterial cell to secrete the enzyme. The presence of the beta-lactamase and the alpha-amylase signal peptides in tandem results in secretion of the enzyme and removal of both signal peptides.  
  Call Number Serial 498  
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Author (up) Meneses, A.; Ponce-Lopez, T.; Tellez, R.; Gonzalez, R.; Castillo, C.; Gasbarri, A. file  url
openurl 
  Title Effects of d-amphetamine on short- and long-term memory in spontaneously hypertensive, Wistar-Kyoto and Sprague-Dawley rats Type Journal Article
  Year 2011 Publication Behavioural Brain Research Abbreviated Journal Behav Brain Res  
  Volume 216 Issue 1 Pages 472-476  
  Keywords Amphetamine/*pharmacology; Analysis of Variance; Animals; Central Nervous System Stimulants/pharmacology; Male; Memory, Long-Term/*drug effects; Memory, Short-Term/*drug effects; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Rats, Sprague-Dawley; Species Specificity  
  Abstract Diverse studies indicate that the attention deficit hyperactivity disorder (ADHD) is associated with alterations in encoding processes, including working or short-term memory. Some ADHD dysfunctional domains are reflected in the spontaneously hypertensive rat (SHR). Here SHR-saline group showed significantly poor STM and LTM relative to SD and WKY saline rats. SD and WKY rats treated with d-amphetamine displayed better STM and LTM, compared to SD-vehicle, WKY-vehicle or SHR-d-amphetamine groups.  
  Call Number Serial 1367  
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Author (up) Muller, G.C.; Hogsette, J.A.; Beier, J.C.; Traore, S.F.; Toure, M.B.; Traore, M.M.; Bah, S.; Doumbia, S.; Schlein, Y. file  url
openurl 
  Title Attraction of Stomoxys sp. to various fruits and flowers in Mali Type Journal Article
  Year 2012 Publication Medical and Veterinary Entomology Abbreviated Journal Med Vet Entomol  
  Volume 26 Issue 2 Pages 178-187  
  Keywords Animals; Feeding Behavior; Flowers; Fruit; Mali; Muscidae--physiology; Species Specificity  
  Abstract The attraction of three Stomoxys species to 26 fruits and 26 flowers of different plant species was investigated in two different sites in Mali during 2008. Stomoxys niger bilineatus Grunberg (Diptera: Muscidae) was attracted to a wider spectrum of species, significantly attracted by four fruits and eight flowers compared with control traps, whereas S. sitiens Rondani (Diptera: Muscidae) was attracted to six fruits and seven flowers of different plants, and S. calcitrans L. (Diptera: Muscidae) was only attracted to one fruit and three flowers. Cold anthrone assays showed a significantly higher prevalence of sugar feeding amongst all three species at the lagoon site than at the site near Mopti. The rhythm of activity study shows temporally separated blood- and sugar-feeding periods for S. niger bilineatus and S. sitiens, but not for S. calcitrans. A comparison between blood and sugar feeding throughout the day shows that sugar feeding activity is as frequent as blood feeding activity. Because not much is known about the preferred sugar sources for Stomoxys species in their natural habitats, the present study provides valuable information regarding the attraction capability of several plants with possible future implication for Stomoxys control strategies.  
  Call Number Serial 403  
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Author (up) Pamplona, R.; Portero-Otin, M.; Requena, J.R.; Thorpe, S.R.; Herrero, A.; Barja, G. file  url
openurl 
  Title A low degree of fatty acid unsaturation leads to lower lipid peroxidation and lipoxidation-derived protein modification in heart mitochondria of the longevous pigeon than in the short-lived rat Type Journal Article
  Year 1999 Publication Mechanisms of Ageing and Development Abbreviated Journal Mech Ageing Dev  
  Volume 106 Issue 3 Pages 283-296  
  Keywords Aging/*physiology; Animals; Cardiolipins/metabolism; Columbidae; Fatty Acids, Unsaturated/*metabolism; *Lipid Peroxidation/physiology; Longevity/*physiology; Male; Malondialdehyde/metabolism; Mitochondria, Heart/*metabolism; Myocardium/metabolism; Phosphatidylcholines/metabolism; Phosphatidylethanolamines/metabolism; Rats; Rats, Wistar; Species Specificity  
  Abstract Birds have a maximum longevity (MLSP) much greater than mammals of similar metabolic rate and body size. Thus, they are ideal models to identify longevity characteristics not linked to low metabolic rates. In this investigation, we show that the fatty acid double bond content of total lipids and phosphatidylcholine, phosphatidylethanolamine and cardiolipin fractions of heart mitochondria is intrinsically lower in pigeons (MLSP = 35 years) than in rats (MLSP = 4 years). This is mainly due to a lower content of the most highly unsaturated docosahexaenoic acid (22:6n-3) and in some fractions arachidonic acid (20:4n-6). The lower double bond content leads to a lower sensitivity to in vitro lipid peroxidation, and is associated with a lower concentration of lipid peroxidation products in vivo, and a lower level of malondialdehyde-lysine protein adducts in heart mitochondria of pigeons than rats. These results, together with those previously obtained in other species or tissues, suggest that a low degree of fatty acid unsaturation is a general characteristic of longevous homeothermic vertebrate animals both when they have low metabolic rates (mammals of large body size) or high metabolic rates (small sized birds). This constitutive trait helps to protect their tissues and mitochondria against lipid peroxidation and oxidative protein modification and can be a factor contributing to their slow rate of aging. The results also show, for the first time in a physiological model, that lipid peroxidizability is related to lipoxidative protein damage.  
  Call Number Serial 123  
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Author (up) Poorter, H.; Niklas, K.J.; Reich, P.B.; Oleksyn, J.; Poot, P.; Mommer, L. file  url
openurl 
  Title Biomass allocation to leaves, stems and roots: meta-analyses of interspecific variation and environmental control Type Journal Article
  Year 2012 Publication The New Phytologist Abbreviated Journal New Phytol  
  Volume 193 Issue 1 Pages 30-50  
  Keywords Biomass; Plant Leaves--growth & development; Plant Roots--growth & development; Plant Stems--growth & development; Species Specificity  
  Abstract We quantified the biomass allocation patterns to leaves, stems and roots in vegetative plants, and how this is influenced by the growth environment, plant size, evolutionary history and competition. Dose-response curves of allocation were constructed by means of a meta-analysis from a wide array of experimental data. They show that the fraction of whole-plant mass represented by leaves (LMF) increases most strongly with nutrients and decreases most strongly with light. Correction for size-induced allocation patterns diminishes the LMF-response to light, but makes the effect of temperature on LMF more apparent. There is a clear phylogenetic effect on allocation, as eudicots invest relatively more than monocots in leaves, as do gymnosperms compared with woody angiosperms. Plants grown at high densities show a clear increase in the stem fraction. However, in most comparisons across species groups or environmental factors, the variation in LMF is smaller than the variation in one of the other components of the growth analysis equation: the leaf area : leaf mass ratio (SLA). In competitive situations, the stem mass fraction increases to a smaller extent than the specific stem length (stem length : stem mass). Thus, we conclude that plants generally are less able to adjust allocation than to alter organ morphology.  
  Call Number Serial 490  
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Author (up) Smith, A.R.; D'Annunzio, L.; Smith, A.E.; Sharma, A.; Hofmann, C.M.; Marshall, N.J.; Carleton, K.L. file  url
openurl 
  Title Intraspecific cone opsin expression variation in the cichlids of Lake Malawi Type Journal Article
  Year 2011 Publication Molecular Ecology Abbreviated Journal Mol Ecol  
  Volume 20 Issue 2 Pages 299-310  
  Keywords Africa; Animals; Cichlids/*genetics/physiology; Color Vision; Cone Opsins/*genetics; Evolution, Molecular; Fresh Water; *Gene Expression; Genetic Variation; Light; Phylogeny; Polymerase Chain Reaction; Retinal Cone Photoreceptor Cells/*metabolism; Sequence Analysis, DNA; Species Specificity; Visual Acuity/*genetics  
  Abstract The expression of cone opsin genes is a primary determinant of the characteristics of colour vision. Interspecific variation in opsin expression is common in African cichlids. It is correlated with foraging among cichlids from Lake Malawi, and with ambient light environment among cichlids from Lake Victoria. In this study, we tested whether gene expression varied within species such that it might be important in contributing to divergence. We hypothesized that light attenuation with depth would be correlated with predictable changes in gene expression in Lake Malawi, and that this variation would tune visual sensitivities to match the ambient light environment. We observed significant differences in cone opsin expression in three different comparisons among populations of the same species. Higher LWS expression was found in shallow versus deep Copadichromis eucinostomus. In Metriaclima zebra, individuals from Zimbawe Rock expressed significantly more SWS2B than those from Thumbi West Island, although these locales have similar ambient light environments. Finally, Tropheops gracilior from deeper water had significantly more variation in expression than their shallow counterparts. These results support that gene expression varies significantly between populations of the same species. Surprisingly, these results could not be explained by predicted visual performance as models predicted that differential expression patterns did not confer sensitivity advantages at different depths. This suggested that expression variation did not confer a local sensitivity advantage. Therefore, our findings were contrary to a primary requirement of the sensory bias hypothesis. As such, other explanations for intraspecific gene expression variation need to be tested.  
  Call Number Serial 2063  
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