261 research outputs found

    Opportunities for Growing Short-Rotation Woody Crops in Agroforestry Practices

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    Technologies are readily available for growing hybrid poplars and willows in block plantings as short-rotation woody crops (SRWC) for fuel and fiber. SRWC species and technologies can also be incorporated into agricultural systems as agroforestry practices. Examples are windbreaks, living snowfences, β€œtimberbelts”, riparian buffer strips, and wastewater treatment plantings. Fast growth, convenient propagation (see AF Note - 11), and compatibility with conventional farming methods make SRWC suitable for use in agroforestry practices to provide multiple benefits such as solid wood and wood fiber products, water quality improvement, crop and soil protection, wildlife habitat, and buffers for agricultural/community interfaces

    Search for the standard model Higgs boson at LEP

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    The impact of maternal HIV infection on cord blood lymphocyte subsets and cytokine profile in exposed non-infected newborns

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    <p>Abstract</p> <p>Background</p> <p>Children born to HIV+ mothers are exposed intra-utero to several drugs and cytokines that can modify the developing immune system, and influence the newborn's immune response to infections and vaccines. We analyzed the relation between the distribution of cord blood lymphocyte subsets and cytokine profile in term newborns of HIV+ mothers using HAART during pregnancy and compared them to normal newborns.</p> <p>Methods</p> <p>In a prospective, controlled study, 36 mother-child pairs from HIV+ mothers and 15 HIV-uninfected mothers were studied. Hematological features and cytokine profiles of mothers at 35 weeks of pregnancy were examined. Maternal and cord lymphocyte subsets as well as B-cell maturation in cord blood were analyzed by flow cytometry. The non-stimulated, as well as BCG- and PHA-stimulated production of IL2, IL4, IL7, IL10, IL12, IFN-Ξ³ and TNF-alpha in mononuclear cell cultures from mothers and infants were quantified using ELISA.</p> <p>Results</p> <p>After one year follow-up none of the exposed infants became seropositive for HIV. An increase in B lymphocytes, especially the CD19/CD5+ ones, was observed in cord blood of HIV-exposed newborns. Children of HIV+ hard drug using mothers had also an increase of immature B-cells. Cord blood mononuclear cells of HIV-exposed newborns produced less IL-4 and IL-7 and more IL-10 and IFN-Ξ³ in culture than those of uninfected mothers. Cytokine values in supernatants were similar in infants and their mothers except for IFN-Ξ³ and TNF-alpha that were higher in HIV+ mothers, especially in drug abusing ones. Cord blood CD19/CD5+ lymphocytes showed a positive correlation with cord IL-7 and IL-10. A higher maternal age and smoking was associated with a decrease of cord blood CD4+ cells.</p> <p>Conclusions</p> <p>in uninfected infants born to HIV+ women, several immunological abnormalities were found, related to the residual maternal immune changes induced by the HIV infection and those associated with antiretroviral treatment. Maternal smoking was associated to changes in cord CD3/CD4 lymphocytes and maternal hard drug abuse was associated with more pronounced changes in the cord B cell line.</p

    Tidal evolution of disky dwarf galaxies in the Milky Way potential: the formation of dwarf spheroidals

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    We conduct high-resolution collisionless N-body simulations to investigate the tidal evolution of dwarf galaxies on an eccentric orbit in the Milky Way (MW) potential. The dwarfs originally consist of a low surface brightness stellar disk embedded in a cosmologically motivated dark matter halo. During 10 Gyr of dynamical evolution and after 5 pericentre passages the dwarfs suffer substantial mass loss and their stellar component undergoes a major morphological transformation from a disk to a bar and finally to a spheroid. The bar is preserved for most of the time as the angular momentum is transferred outside the galaxy. A dwarf spheroidal (dSph) galaxy is formed via gradual shortening of the bar. This work thus provides a comprehensive quantitative explanation of a potentially crucial morphological transformation mechanism for dwarf galaxies that operates in groups as well as in clusters. We compare three cases with different initial inclinations of the disk and find that the evolution is fastest when the disk is coplanar with the orbit. Despite the strong tidal perturbations and mass loss the dwarfs remain dark matter dominated. For most of the time the 1D stellar velocity dispersion, \sigma, follows the maximum circular velocity, V_{\rm max}, and they are both good tracers of the bound mass. Specifically, we find that M_{\rm bound} \propto V_{\rm max}^{3.5} and V_{\rm max} \sim \sqrt{3} \sigma in agreement with earlier studies based on pure dark matter simulations. The latter relation is based on directly measuring the stellar kinematics of the simulated dwarf and may thus be reliably used to map the observed stellar velocity dispersions of dSphs to halo circular velocities when addressing the missing satellites problem.Comment: 16 pages, 14 figures, significantly revised version with new simulations analyzed, accepted for publication in MNRA

    Nomenclature- and Database-Compatible Names for the Two Ebola Virus Variants that Emerged in Guinea and the Democratic Republic of the Congo in 2014

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    In 2014, Ebola virus (EBOV) was identified as the etiological agent of a large and still expanding outbreak of Ebola virus disease (EVD) in West Africa and a much more confined EVD outbreak in Middle Africa. Epidemiological and evolutionary analyses confirmed that all cases of both outbreaks are connected to a single introduction each of EBOV into human populations and that both outbreaks are not directly connected. Coding-complete genomic sequence analyses of isolates revealed that the two outbreaks were caused by two novel EBOV variants, and initial clinical observations suggest that neither of them should be considered strains. Here we present consensus decisions on naming for both variants (West Africa: β€œMakona”, Middle Africa: β€œLomela”) and provide database-compatible full, shortened, and abbreviated names that are in line with recently established filovirus sub-species nomenclatures

    Non-invasive muscle contraction assay to study rodent models of sarcopenia

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    <p>Abstract</p> <p>Background</p> <p>Age-related sarcopenia is a disease state of loss of muscle mass and strength that affects physical function and mobility leading to falls, fractures, and disability. The need for therapies to treat age-related sarcopenia has attracted intensive preclinical research. To facilitate the discovery of these therapies, we have developed a non-invasive rat muscle functional assay system to efficiently measure muscle force and evaluate the efficacy of drug candidates.</p> <p>Methods</p> <p>The lower leg muscles of anesthetized rats are artificially stimulated with surface electrodes on the knee holders and the heel support, causing the lower leg muscles to push isometric pedals that are attached to force transducers. We developed a stimulation protocol to perform a fatigability test that reveals functional muscle parameters like maximal force, the rate of fatigue, fatigue-resistant force, as well as a fatigable muscle force index. The system is evaluated in a rat aging model and a rat glucocorticoid-induced muscle loss model</p> <p>Results</p> <p>The aged rats were generally weaker than adult rats and showed a greater reduction in their fatigable force when compared to their fatigue-resistant force. Glucocorticoid treated rats mostly lost fatigable force and fatigued at a higher rate, indicating reduced force from glycolytic fibers with reduced energy reserves.</p> <p>Conclusions</p> <p>The involuntary contraction assay is a reliable system to assess muscle function in rodents and can be applied in preclinical research, including age-related sarcopenia and other myopathy.</p

    Molecular Characterization of a Novel Intracellular ADP-Ribosyl Cyclase

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    Background. ADP-ribosyl cyclases are remarkable enzymes capable of catalyzing multiple reactions including the synthesis of the novel and potent intracellular calcium mobilizing messengers, cyclic ADP-ribose and NAADP. Not all ADP-ribosyl cyclases however have been characterized at the molecular level. Moreover, those that have are located predominately at the outer cell surface and thus away from their cytosolic substrates. Methodology/Principal Findings. Here we report the molecular cloning of a novel expanded family of ADP-ribosyl cyclases from the sea urchin, an extensively used model organism for the study of inositol trisphosphate-independent calcium mobilization. We provide evidence that one of the isoforms (SpARC1) is a soluble protein that is targeted exclusively to the endoplasmic reticulum lumen when heterologously expressed. Catalytic activity of the recombinant protein was readily demonstrable in crude cell homogenates, even under conditions where luminal continuity was maintained. Conclusions/Significance. Our data reveal a new intracellular location for ADP-ribosyl cyclases and suggest that production of calcium mobilizing messengers may be compartmentalized
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