2,213 research outputs found
The Microstructure of Wheat: Its Development and Conversion Into Bread
Wheat endosperm development has been studied in numerous laboratories. The genera 1 i zed scheme of protein body formation assembled from these data indicates that storage proteins are initially formed in the rough endoplasmic reticulum (RER). The storage proteins in RER may be processed via the Golgi apparatus into vesicles that enlarge by several mechanisms into membrane-bounded protein bodies. The prote in bodies are transported through the cytoplasm to the vacuole where they fuse with the tonoplast and deposit the protein granules into the vacuoles. The protein granules fuse with one another, lose water, and eventually become transformed into the matrix. The starchy endosperm is reduced to small particles of starch and protein during milling. These flour particles are dynamically rehydrated during dough formation. The protein forms the major structural network surrounding starch granules in doughs. The framework of bread crumb, however, is of dual composition; the protein network and a newly formed network of gelatinized starch
Contributing to WUDAPT: A Local Climate Zone Classification of Two Cities in Ukraine
Local climate zones (LCZs) divide the urban landscape into homogeneous types based on urban structure (i.e.,morphology of streets and buildings), urban cover (i.e., permeability of surfaces), construction materials, and human activities (i.e., anthropogenic heat). This classification scheme represents a standardized way of capturing the basic urban form of cities and is currently being applied globally as part of the world urban database and portal tools (WUDAPT) initiative. This paper assesses the transferability of the LCZ concept to two Ukrainian cities, i.e., Kyiv and Lviv, which differ in urban form and topography, and considers three ways to validate and verify this classification
scheme. An accuracy of 64% was achieved for Kyiv using an independent validation dataset while a comparison of the LCZ maps with the GlobeLand30 land cover map resulted in a match that was greater than 75% for both cities. There was also good correspondence between the urban classes in the LCZ maps and the urban points of interest in OpenStreetMap (OSM). However, further research is still required to produce a standardized validation protocol that could be used on a regular basis by contributors to WUDAPT to help produce more accurate LCZ maps in the future
Open Data for Global Multimodal Land Use Classification: Outcome of the 2017 IEEE GRSS Data Fusion Contest
In this paper, we present the scientific outcomes of the 2017 Data Fusion Contest organized by the Image Analysis and Data Fusion Technical Committee of the IEEE Geoscience and Remote Sensing Society. The 2017 Contest was aimed at addressing the problem of local climate zones classification based on a multitemporal and multimodal dataset, including image (Landsat 8 and Sentinel-2) and vector data (from OpenStreetMap). The competition, based on separate geographical locations for the training and testing of the proposed solution, aimed at models that were accurate (assessed by accuracy metrics on an undisclosed reference for the test cities), general (assessed by spreading the test cities across the globe), and computationally feasible (assessed by having a test phase of limited time). The techniques proposed by the participants to the Contest spanned across a rather broad range of topics, and of mixed ideas and methodologies deriving from computer vision and machine learning but also deeply rooted in the specificities of remote sensing. In particular, rigorous atmospheric correction, the use of multidate images, and the use of ensemble methods fusing results obtained from different data sources/time instants made the difference
Long-Term Potentiation: One Kind or Many?
Do neurobiologists aim to discover natural kinds? I address this question in this chapter via a critical analysis of classification practices operative across the 43-year history of research on long-term potentiation (LTP). I argue that this 43-year history supports the idea that the structure of scientific practice surrounding LTP research has remained an obstacle to the discovery of natural kinds
Potentiality in Biology
We take the potentialities that are studied in the biological sciences (e.g., totipotency) to be an important subtype of biological dispositions. The goal of this paper is twofold: first, we want to provide a detailed understanding of what biological dispositions are. We claim that two features are essential for dispositions in biology: the importance of the manifestation process and the diversity of conditions that need to be satisfied for the disposition to be manifest. Second, we demonstrate that the concept of a disposition (or potentiality) is a very useful tool for the analysis of the explanatory practice in the biological sciences. On the one hand it allows an in-depth analysis of the nature and diversity of the conditions under which biological systems display specific behaviors. On the other hand the concept of a disposition may serve a unificatory role in the philosophy of the natural sciences since it captures not only the explanatory practice of biology, but of all natural sciences. Towards the end we will briefly come back to the notion of a potentiality in biology
Vacuole Formation in Wheat Starchy Endosperm
The formation of vacuoles in wheat (Triticum aestivum cv. Highbury) starchy endosperm cells was studied using electron microscopy. Some vacuoles were always present, even in the coenocytic cytoplasm. The first formed endosperm cells were highly vacuolated, but became filled with cytoplasm as they grew older. Various-sized pieces of cytoplasm were found in vacuoles of developing endosperm cells, probably as a result of autophagic sequestration. The membranes of the autographic vacuoles appeared to originate from the rough endoplasmic reticulum and from extensions of already-formed vacuoles. Autographic activity was confirmed by localizing the hydrolytic enzyme acid phosphatase within the vacuoles. The rough endoplasmic reticulum (RER) also stained positive for this enzyme
Associations of Starch Gel Hardness, Granule Size, Waxy Allelic Expression, Thermal Pasting, Milling Quality, and Kernel Texture of 12 Soft Wheat Cultivars
Starches were isolated from 12 soft wheat (Triticum aestivum L.) cultivars and were characterized for waxy (Wx) allelic expression, thermal pasting characteristics, and starch granule size. Gels were produced from the thermally degraded starches and were evaluated using large deformation rheological measurements. Data were compared with cultivar kernel texture, milling characteristics, starch chemical analyses, and flour pasting characteristics. Larger flour yields were produced from cultivars that had larger starch granules. Flour yield also was correlated with lower amylose content and greater starch content. Harder starch gels were correlated with higher levels of amylose content and softer kernel texture. The cultivar Fillmore, which had a partial waxy mutation at the B locus, produced the highest peak pasting viscosity and the lowest gel hardness. Softer textured wheats had greater lipid‐complexed amylose and starch phosphorus contents and had less total starch content. Among these wheats of the soft market class, softer textured wheats had larger starch granules and harder textured wheats had smaller starch granules. In part, this may explain why soft wheats vary in texture. The smaller granules have larger surface area available for noncovalent bonding with the endosperm protein matrix and they also may pack more efficiently, producing harder endosperm.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141588/1/cche0163.pd
Weak-strong uniqueness property for the full Navier-Stokes-Fourier system
The Navier-Stokes-Fourier system describing the motion of a compressible,
viscous, and heat conducting fluid is known to possess global-in-time weak
solutions for any initial data of finite energy. We show that a weak solution
coincides with the strong solution, emanating from the same initial data, as
long as the latter exists. In particular, strong solutions are unique within
the class of weak solutions
H-ferritin ferroxidase induces cytoprotective pathways and inhibits microvascular stasis in transgenic sickle mice
Hemolysis, oxidative stress, inflammation, vaso-occlusion and organ infarction are hallmarks of sickle cell disease (SCD). We have previously shown that increases in heme oxygenase-1 (HO-1) activity detoxify heme and inhibit vaso-occlusion in transgenic mouse models of SCD. HO-1 releases Fe2+ from heme, and the ferritin heavy chain (FHC) ferroxidase oxidizes iron to catalytically-inactive Fe3+ inside ferritin. FHC overexpression has been shown to be cytoprotective. In this study, we hypothesized that overexpression of FHC and its ferroxidase activity will inhibit inflammation and microvascular stasis in transgenic sickle mice in response to stroma-free hemoglobin. We utilized a Sleeping Beauty transposase plasmid to deliver a human wild-type-ferritin heavy chain (wt-hFHC) transposable element by hydrodynamic tail vein injections to NY1DD SCD mice. Control mice were infused with the same volume of lactated Ringer's solution (LRS) or a triple missense human FHC (ms-hFHC) plasmid with no ferroxidase activity. Eight weeks later, LRS-injected mice had ~40% microvascular stasis (% non-flowing venules) when infused with stroma-free hemoglobin at 1 h, while mice overexpressing wt-hFHC had only 5% stasis (p< 0.05), and ms-hFHC mice had 33% stasis suggesting vascular protection by ferroxidase active wt-hFHC. The wt-hFHC SCD mice had marked increases in splenic hFHC mRNA and hepatic hFHC protein, light chain ferritin, 5-aminolevulinic acid synthase (5-ALA-synthase), heme content, ferroportin, nuclear factor erythroid 2-related factor 2 (Nrf2), nuclear hFHC, and microsomal HO-1 activity and protein, and a decrease in activated nuclear phosho-nuclear factor-kappa B (NF-κB) p65. HO-1 activity was not essential for the protection by FHC. We conclude that wt-hFHC ferroxidase activity enhances cytoprotective Nrf2-regulated proteins including HO-1, thereby resulting in decreased NF-κB-activation, inflammation and microvascular stasis in transgenic SCD mice
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