Text provides data on all key aspects of metallic materials, including narrative information on metallurgical and related topics. Chapters have been extensively revised or rewritten completely to ...reflect the current state of the art. Coverage has been expanded to include data on additional classes of metallic materials, heat-treatment technologies, and more. Provides an invaluable reference source for all workers, libraries and research laboratories in the field of engineering and metallurgy.
Viral infection of mammalian host results in the activation of innate immune responses. Toll-like receptors (TLRs) have been shown to mediate the recognition of many types of pathogens, including ...viruses. The genomes of viruses possess unique characteristics that are not found in mammalian genomes, such as high CpG content and double-stranded RNA. These genomic nucleic acids serve as molecular signatures associated with viral infections. Here we show that TLR7 recognizes the single-stranded RNA viruses, vesicular stomatitis virus and influenza virus. The recognition of these viruses by plasmacytoid dendritic cells and B cells through TLR7 results in their activation of costimulatory molecules and production of cytokines. Moreover, this recognition required intact endocytic pathways. Mice deficient in either the TLR7 or the TLR adaptor protein MyD88 demonstrated reduced responses to in vivo infection with vesicular stomatitis virus. These results demonstrate microbial ligand recognition by TLR7 and provide insights into the pathways used by the innate immune cells in the recognition of viral pathogens.
Iron and steel plants producing steel via the blast furnace-basic oxygen furnace (BF-BOF) route constitute among the largest single point CO2 emitters within the European Union (EU). As the iron ore ...reduction process in the blast furnace is fully dependent on carbon mainly supplied by coal and coke, bioenergy is the only renewable that presents a possibility for their partial substitution. Using the BeWhere model, this work optimised the mobilization and use of biomass resources within the EU in order to identify the opportunities that bioenergy can bring to the 30 operating BF-BOF plants.
The results demonstrate competition for the available biomass resources within existing industries and economically unappealing prices of the bio-based fuels. A carbon dioxide price of 60 € t−1 is required to substitute 20% of the CO2 emissions from the fossil fuels use, while a price of 140 € t−1 is needed to reach the maximum potential of 42%. The possibility to use organic wastes to produce hydrochar would not enhance the maximum emission reduction potential, but it would broaden the available feedstock during the low levels of substitution.
The scope for bioenergy integration is different for each plant and so consideration of its deployment should be treated individually. Therefore, the EU-ETS (Emission Trading System) may not be the best policy tool for bioenergy as an emission reduction strategy for the iron and steel industry, as it does not differentiate between the opportunities across the different steel plants and creates additional costs for the already struggling European steel industry.
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•Full biomass demand by iron and steel plants can be met in the EU.•Use of bio-products in steel plants is viable only at a high CO2 price.•Hydrothermal carbonisation of waste could help initial fossil fuel substitution.•Maximum CO2 emission reduction possible is 91 Mt per year (42%).•Imposing required CO2 price would significantly impact steel production costs.
Abstract
Orchids are one of the largest plant families and are commercially traded for a variety of purposes, including as ornamental plants, medicinal products and food. These markets involve ...thousands of species, which may be traded legally or illegally, sustainably or unsustainably, and take place at local, national or international scales. In this review, we provide the first overview of commercial orchid trade globally and highlight the main types that involve wild-collected plants. Much of this trade is the result of illegal harvest meaning that it is little documented and is absent from official statistics, at the same time as being of growing conservation concern. We discuss the associated legal–regulatory context, identify key conservation challenges and highlight four key priorities for addressing these challenges. These are to (1) research trade dynamics and the impacts of harvest; (2) strengthen the legal trade of orchids; (3) adopt measures to reduce illegal trade; and (4) raise the profile of orchid trade among policy makers, conservationists and the public.
A recent explosion in newly discovered vascular growth factors has coincided with exploitation of powerful new genetic approaches for studying vascular development. An emerging rule is that all of ...these factors must be used in perfect harmony to form functional vessels. These new findings also demand re-evaluation of therapeutic efforts aimed at regulating blood vessel growth in ischaemia, cancer and other pathological settings.
Genetic deletion studies have shown that haploinsufficiency of Delta-like ligand (Dll) 4, a transmembrane ligand for the Notch family of receptors, results in major vascular defects and embryonic ...lethality. To better define the role of Dll4 during vascular growth and differentiation, we selected the postnatal retina as a model because its vasculature develops shortly after birth in a highly stereotypic manner, during which time it is accessible to experimental manipulation. We report that Dll4 expression is dynamically regulated by VEGF in the retinal vasculature, where it is most prominently expressed at the leading front of actively growing vessels. Deletion of a single Dll4 allele or pharmacologic inhibition of Dll4/Notch signaling by intraocular administration of either soluble Dll4-Fc or a blocking antibody against Dll4 all produced the same set of characteristic abnormalities in the developing retinal vasculature, most notably enhanced angiogenic sprouting and increased endothelial cell proliferation, resulting in the formation of a denser and more highly interconnected superficial capillary plexus. In a model of ischemic retinopathy, Dll4 blockade also enhanced angiogenic sprouting and regrowth of lost retinal vessels while suppressing ectopic pathological neovascularization. Our data demonstrate that Dll4 is induced by VEGF as a negative feedback regulator and acts to prevent overexuberant angiogenic sprouting, promoting the timely formation of a well differentiated vascular network.
Transient liquid phase bonding Gale, W.F.; Butts, D.A.
Science and technology of welding and joining,
08/2004, Letnik:
9, Številka:
4
Journal Article
Recenzirano
A review of the transient liquid phase (TLP) bonding process is presented in this paper. This review concentrates on the mechanisms of the TLP process, including both microstructural development and ...wettability aspects. However, design related issues and engineering applications are also considered. The paper explains how the TLP bonding process offers the potential for producing joints with microstructures and hence mechanical properties that are similar to those of the parent materials. The process of isothermal solidification is discussed at some length. The paper considers the ways in which specific microstructural features of the substrate material-interlayer material combination influence microstructural development. A distinction is drawn between cases where the progression of isothermal solidification dominates the final microstructure and those where events occurring after the completion of isothermal solidification are paramount. The paper describes the practical limitations on the production of parent-metal-like microstructures and the complexity of microstructural development in real materials, especially where dissimilar substrates are involved. Modification of the TLP bonding process to accommodate cases of limited solid solubility and/or low diffusion coefficients is discussed.
VEGF and Angiopoietin-1 requisitely collaborate during blood vessel development. While Angiopoietin-1 obligately activates its Tie2 receptor, Angiopoietin-2 can activate Tie2 on some cells, while it ...blocks Tie2 activation on others. Our analysis of mice lacking Angiopoietin-2 reveals that Angiopoietin-2 is dispensable for embryonic vascular development but is requisite for subsequent angiogenic remodeling. Unexpectedly, mice lacking Angiopoietin-2 also exhibit major lymphatic vessel defects. Genetic rescue with Angiopoietin-1 corrects the lymphatic, but not the angiogenesis, defects, suggesting that Angiopoietin-2 acts as a Tie2 agonist in the former setting, but as an antagonist in the latter setting. Our studies define a vascular growth factor whose primary role is in postnatal angiogenic remodeling and also demonstrate that members of the VEGF and Angiopoietin families collaborate during development of the lymphatic vasculature.
Obsessive-compulsive disorder (OCD) is a common psychiatric disorder defined by the presence of obsessive thoughts and repetitive compulsive actions, and it often encompasses anxiety and depressive ...symptoms. Recently, the corticostriatal circuitry has been implicated in the pathogenesis of OCD. However, the etiology, pathophysiology and molecular basis of OCD remain unknown. Several studies indicate that the pathogenesis of OCD has a genetic component. Here we demonstrate that loss of a neuron-specific transmembrane protein, SLIT and NTRK-like protein-5 (Slitrk5), leads to OCD-like behaviors in mice, which manifests as excessive self-grooming and increased anxiety-like behaviors, and is alleviated by the selective serotonin reuptake inhibitor fluoxetine. Slitrk5−/− mice show selective overactivation of the orbitofrontal cortex, abnormalities in striatal anatomy and cell morphology and alterations in glutamate receptor composition, which contribute to deficient corticostriatal neurotransmission. Thus, our studies identify Slitrk5 as an essential molecule at corticostriatal synapses and provide a new mouse model of OCD-like behaviors.
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