80 research outputs found

    Absorption and nutrient concentration in apple (Pyrus mains L.)

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    In order to obtain the following informations: a) dry matter production and extraction of nutrients by the fruits at different ages; b) dry matter production and extraction of nutrient by the leaves and "trunk + branches" collected at the flowering stage; c) dry matter production and export of nutrients by pruning (leaves and branches) at the begining dormant stage; A trial was conducted on Latossolo Vermelho Escuro Orto group (Orthox) at Buri, São Paulo State, Brazil. The material was collected from 'Ohio Beauty' and 'Brazil' apples grafted on 'Doucin' 1-2; 3-4; 4-5 and 6-7 years old. The main conclusions were as follows: a) differences were observed on dry matter production by two varieties at the different stages of growth; b) differences were also observed between the two varieties on the matter production in the leaves and "trunk + branches" at the flowering stage, as well as by the leaves and branches pruned at the begining of dormant stages; c) differences were observed betwen the two varieties concerning to nutrient concentration (on dry matter basis) on the fruits collected at different stages of growth. Same results were observed on leaves and "trunk + branches" collected at flowering period; d) differences were observed on the exportation of the nutrients referring to growth period of fruit; e) at the flowering and dormant period, differences were observed on the contents of nutrients in the leaves, 'trunk + branches', on the two varieties; f) the nutrient exportation by the fruits obyed the following order: K>;N>;P>;S>;Ca>;Mg>;Fe>;B >; Cu >; Mn >; Zn >; Mo; g) the nutrient extration by the aerial part the apple trees obyed the following order: N >; K >; Ca >; Mg >; P >; S >; Fe >; B >; Cu = Mn = Zn.O ensaio foi conduzido com macieiras 'Ohio Beauty' e 'Brasil' com 1-2, 3-4, 4-5 r 6-7 anos, enxertadas sobre macieira 'Doucin,'no município de Buri (SP-Brasil), situadas sobre Latossolo Vermelho Escuro Orto, em espaçamento 5,5 x 3,0 m. Objetivou-se: 1) analisar a produção de matéria seca e extração de nutrientes pelos frutos em diferentes es tédios de desenvolvimento: 2) analisar a produção de matéria seca e extração de nutrientes por folhas e "tronco + galhos" coletados no florescimento e por folhas e galhos podados no início da dormência. Foram determinados teores de N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, Mo e Zn. Concluiu-se que: "Macieira 'Ohio Beauty" e 'Brasil' diferem nos acúmulos de matéria seca pelos frutos coletados, em diferentes estádios de desenvolvimento, nos acúmulos pelas folhas e "tronco+galhos" coletados no florescimento, e nos acúmulos pelas folhas e galhos podados no início da dormência. Macieiras 'Ohyo Beauty' e 'Brasil' diferem nas concentrações de nutrientes em frutos coletados em diferentes estádios de desenvolvimento, e nas concentra -ções em folhas e "tronco + galhos" coletados no florescimento. Macieiras Ohio Beauty' e 'Brasil' diferem na extração de nutrientes pelos frutos coletados em diferentes estádios de desenvolvimento, na extração por folhas e "tronco + galhos" no florescimento e na extração por folhas e galhos coletados no início da dormência. A extração de nutrientes pelos frutos obedece a seguinte ordem: K>;N>;P>;S>;Ca>;Mg >; Fe >; B >; Cu >; Mn >; Zn >; Mo. A extração de nutrientes pela macieira (parte aérea obedece a seguinte ordem: N >; P >; Ca >; Mg >; P>; S >; Fe >; B >; Cu = Mn = Zn

    Candidate Glutamatergic Neurons in the Visual System of Drosophila

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    The visual system of Drosophila contains approximately 60,000 neurons that are organized in parallel, retinotopically arranged columns. A large number of these neurons have been characterized in great anatomical detail. However, studies providing direct evidence for synaptic signaling and the neurotransmitter used by individual neurons are relatively sparse. Here we present a first layout of neurons in the Drosophila visual system that likely release glutamate as their major neurotransmitter. We identified 33 different types of neurons of the lamina, medulla, lobula and lobula plate. Based on the previous Golgi-staining analysis, the identified neurons are further classified into 16 major subgroups representing lamina monopolar (L), transmedullary (Tm), transmedullary Y (TmY), Y, medulla intrinsic (Mi, Mt, Pm, Dm, Mi Am), bushy T (T), translobula plate (Tlp), lobula intrinsic (Lcn, Lt, Li), lobula plate tangential (LPTCs) and lobula plate intrinsic (LPi) cell types. In addition, we found 11 cell types that were not described by the previous Golgi analysis. This classification of candidate glutamatergic neurons fosters the future neurogenetic dissection of information processing in circuits of the fly visual system

    Transcriptomic profiling of host-parasite interactions in the microsporidian <i>Trachipleistophora hominis</i>

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    BACKGROUND: Trachipleistophora hominis was isolated from an HIV/AIDS patient and is a member of a highly successful group of obligate intracellular parasites. METHODS: Here we have investigated the evolution of the parasite and the interplay between host and parasite gene expression using transcriptomics of T. hominis-infected rabbit kidney cells. RESULTS: T. hominis has about 30 % more genes than small-genome microsporidians. Highly expressed genes include those involved in growth, replication, defence against oxidative stress, and a large fraction of uncharacterised genes. Chaperones are also highly expressed and may buffer the deleterious effects of the large number of non-synonymous mutations observed in essential T. hominis genes. Host expression suggests a general cellular shutdown upon infection, but ATP, amino sugar and nucleotide sugar production appear enhanced, potentially providing the parasite with substrates it cannot make itself. Expression divergence of duplicated genes, including transporters used to acquire host metabolites, demonstrates ongoing functional diversification during microsporidian evolution. We identified overlapping transcription at more than 100 loci in the sparse T. hominis genome, demonstrating that this feature is not caused by genome compaction. The detection of additional transposons of insect origin strongly suggests that the natural host for T. hominis is an insect. CONCLUSIONS: Our results reveal that the evolution of contemporary microsporidian genomes is highly dynamic and innovative. Moreover, highly expressed T. hominis genes of unknown function include a cohort that are shared among all microsporidians, indicating that some strongly conserved features of the biology of these enormously successful parasites remain uncharacterised. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12864-015-1989-z) contains supplementary material, which is available to authorized users

    Evidence-based Kernels: Fundamental Units of Behavioral Influence

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    This paper describes evidence-based kernels, fundamental units of behavioral influence that appear to underlie effective prevention and treatment for children, adults, and families. A kernel is a behavior–influence procedure shown through experimental analysis to affect a specific behavior and that is indivisible in the sense that removing any of its components would render it inert. Existing evidence shows that a variety of kernels can influence behavior in context, and some evidence suggests that frequent use or sufficient use of some kernels may produce longer lasting behavioral shifts. The analysis of kernels could contribute to an empirically based theory of behavioral influence, augment existing prevention or treatment efforts, facilitate the dissemination of effective prevention and treatment practices, clarify the active ingredients in existing interventions, and contribute to efficiently developing interventions that are more effective. Kernels involve one or more of the following mechanisms of behavior influence: reinforcement, altering antecedents, changing verbal relational responding, or changing physiological states directly. The paper describes 52 of these kernels, and details practical, theoretical, and research implications, including calling for a national database of kernels that influence human behavior

    Purinergic signalling and immune cells

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    This review article provides a historical perspective on the role of purinergic signalling in the regulation of various subsets of immune cells from early discoveries to current understanding. It is now recognised that adenosine 5'-triphosphate (ATP) and other nucleotides are released from cells following stress or injury. They can act on virtually all subsets of immune cells through a spectrum of P2X ligand-gated ion channels and G protein-coupled P2Y receptors. Furthermore, ATP is rapidly degraded into adenosine by ectonucleotidases such as CD39 and CD73, and adenosine exerts additional regulatory effects through its own receptors. The resulting effect ranges from stimulation to tolerance depending on the amount and time courses of nucleotides released, and the balance between ATP and adenosine. This review identifies the various receptors involved in the different subsets of immune cells and their effects on the function of these cells

    Effective and safe proton pump inhibitor therapy in acid-related diseases – A position paper addressing benefits and potential harms of acid suppression

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    Epidemiologic studies of modifiable factors associated with cognition and dementia: systematic review and meta-analysis

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