Morphogenetic Characteristics of \u3cem\u3ePanicum Maximum\u3c/em\u3e cv. Aruana Subjected to Five Defoliation Stubble Heights and Two Frequencies

Tillers in grass swards are subject to size density compensation and this mechanism has been observed to follow the -3/2 self thinning rule. This theory assumes that tiller components (leaf lamina and stems) have a constant geometry as the sward is taller or shorter. In a re examination of this rule (SackvilleHamilton et al., 1995) observed that in grass swards the slope can be different from -3/2 depending on the extremes of defoliation (Hernandez-Garay et al., 1999). Therefore, the dimensionless measure, R (ratio tiller leaf area : volume) was proposed to isolate the tiller geometry component from the tiller size. Guinea grass is the second most sown grass in Brazilian pastures and cv. Aruana has been used successfully in the past ten years in sheep grazing systems. Since this bunch grass presents numerous aerial tillers that contribute to yield, the objective of this paper was to evaluate changes in tiller leaf area and volume on plants subjected to high frequency (simulating a continuous grazing), and low frequency defoliation (simulating an intermittent grazing), under different defoliation stubble heights

Diltiazem downregulates IL-12 production by human dendritic cells

It is well known that IL-12 plays a central role in the initiation and control of allogeneic immune response. It promotes the proliferation of lymphocytes and NK cells, cytotoxic activity of NK cells, and CTL. It was recently shown that IL-12 is involved in the regulation of T helper Th1-Th2 responses by exerting stimulatory effects on Th1 and inhibitory effects on Th2. This regulatory role is believed to result from the ability of IL-12 to induce IFN-γ production in activated T cells and NK cells.[1 and 2] Th1 cytokines (IL-2 and IFN-γ) promote both CTL and delayed-type hypersensitivity (DTH) responses, which are considered the principal effector mechanisms of allograft rejection. Diltiazem, a calcium channel blocker used in organ transplantation, is often included in clinical protocols in association with cyclosporin A and corticosteroids.[3] It was used initially because of its antinephrotoxic and antihypertensive effects, so that the undesirable side effects induced by immunosuppressive therapy could be reduced. We previously studied the effect of diltiazem on human mixed lymphocyte reactions (MLR) and on isolated human monocytes, showing the capacity of this drug to affect proinflammatory cytokine production.[4 and 5] Since dendritic cells (DCs) are the most effective antigen-presenting cells (APCs) to prime naive T cells, we were interested in determining the influence of diltiazem on human DCs. Human DCs generated from peripheral blood monocytes in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4) have been characterised as immature DCs. To become fully potent APCs, DCs must undergo maturation induced either by a proinflammatory signal such as lipopolysaccharide (LPS) or by interaction with CD40L expressed on activated T lymphocytes. [6] The ability of mature DCs to act as potent APCs is due to their high expression of MHC and costimulatory molecules and also to their production of cytokines, especially IL-12. Therefore, we determined the effect of diltiazem on cytokine production by human DCs with a particular interest in IL-1β, IL-6, TNF-α, and IL-12 production

Tiller Population Stability of Aruana Guineagrass Subjected to Cutting Severities and Fertilized with Nitrogen

Tiller appearance, death and survival rates determine the persistency of each grass species and their herbage accumulation. The balance between these factors may vary with frequency and intensity of grazing and nitrogen (N) fertilization. Separated analysis of data on tiller appearance and survival or death may not indicate if tiller population is stable in a given time, that is, if tiller appearance in relation to tiller survival is large enough to maintain tiller population stable. In order to avoid that, an integrated analysis of tiller appearance and death was used, the tiller population stability index (SI), as defined by Bahmani et al. (2003). Aruana Guineagrass (Panicum maximum Jacques cv. Aruana) is widely used as pasture for sheep, which are extremely susceptible to infestation by larvae of gastrointestinal parasites in tropical pasture-based systems. One way to mitigate this problem, reducing the need for the use of anthelmintics, is by managing pastures with post-grazing height low enough to favor the incidence of sunlight at the base of tussocks, killing and controlling larval development, without jeopardizing canopy regrowth and persistence. Sward targets for grazing Aruana Guineagrass correspond to a pre-grazing height of 30 cm, equivalent to 95% canopy light interception during regrowth, and a post-grazing height of 15 cm (Zanini et al. 2012). The objective of this experiment was to evaluate tiller population stability of Aruana Guineagrass subjected to cutting severities and N fertilization using the stability index

Production of Aruana Guinea Grass Submitted to Cutting Severities and Nitrogen Fertilization

Aruana Guineagrass (Panicum maximum Jacques cv. Aruana) is widely used as pasture for sheep, which are extremely susceptible to infestation by larvae of gastrointestinal parasites in tropical pasture-based systems (Zanini et al. 2012) A way to mitigate this problem, and consequently reduce the need for use of anthelmintics, is by managing pastures with post-grazing height low enough to favor the incidence of sunlight at the base of tussocks that will kill and control larval development, without jeopardizing canopy regrowth and persistence. The pre-grazing sward height recommended for Aruana Guineagrass is 30 cm, when the canopy intercepts 95% of the incident light, and a 15 cm post-grazing height (Zanini et al. 2012). As cutting severity and nitrogen (N) fertilization cause morphological and physiological adaptations in individual plants - altering the production of forage grasses - the objective of this study was to evaluate the accumulation of morphological components of Aruana Guineagrass subjected to cutting severities and N fertilization

Probing host pathogen cross-talk by transcriptional profiling of both Mycobacterium tuberculosis and infected human dendritic cells and macrophages

This study provides the proof of principle that probing the host and the microbe transcriptomes simultaneously is a valuable means to accessing unique information on host pathogen interactions. Our results also underline the extraordinary plasticity of host cell and pathogen responses to infection, and provide a solid framework to further understand the complex mechanisms involved in immunity to M. tuberculosis and in mycobacterial adaptation to different intracellular environments

A Roadmap for HEP Software and Computing R&D for the 2020s

Particle physics has an ambitious and broad experimental programme for the coming decades. This programme requires large investments in detector hardware, either to build new facilities and experiments, or to upgrade existing ones. Similarly, it requires commensurate investment in the R&D of software to acquire, manage, process, and analyse the shear amounts of data to be recorded. In planning for the HL-LHC in particular, it is critical that all of the collaborating stakeholders agree on the software goals and priorities, and that the efforts complement each other. In this spirit, this white paper describes the R&D activities required to prepare for this software upgrade.Peer reviewe