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Sample records for distribution ultrastructural localization

  1. Transport, ultrastructural localization, and distribution of chemical forms of lead in radish (Raphanus sativus L.).

    Science.gov (United States)

    Wang, Yan; Shen, Hong; Xu, Liang; Zhu, Xianwen; Li, Chao; Zhang, Wei; Xie, Yang; Gong, Yiqin; Liu, Liwang

    2015-01-01

    Lead (Pb), a ubiquitous but highly toxic heavy metal (HM), is harmful to human health through various pathways including by ingestion of contaminated vegetables. Radish is a worldwide root vegetable crop with significant health and nutritional benefits. However, little is known about Pb translocation and distribution within radish plants after its uptake by the roots. In this study, Pb stress was induced using Pb(NO3)2 in hydroponic culture, aiming to characterize the transport, ultrastructural localization, and distribution of chemical forms of Pb in different tissues of radish. The results showed that the majority of Pb (85.76-98.72%) was retained in underground organs including lateral roots, root heads and taproot skins, while a small proportion of Pb was absorbed by root flesh (0.44-1.56%) or transported to the shoot (1.28-14.24%). A large proportion of Pb (74.11-99.30%) was integrated with undissolved Pb oxalate, protein and pectates forming Pb-phosphate complexes. Moreover, a low-Pb-accumulating line of radish showed a higher proportion of Pb in water-soluble form compared with a high-Pb-accumulating line. Subcellular distribution analysis showed that a large proportion of Pb was bound to cell wall fraction in lateral roots (71.08-80.40%) and taproot skin (46.22-77.94%), while the leaves and roots had 28.36-39.37% and 27.35-46.51% of Pb stored in the soluble fraction, respectively. Furthermore, transmission electron microscopy (TEM) revealed Pb precipitates in intercellular space, cell wall, plasma lemma and vacuoles. Fractionation results also showed the accumulation of Pb on the cell wall, intercellular space and vacuole, and low uptake of undissolved Pb oxalate, protein, pectates and Pb-phosphate complexes, which might be due to low transport efficiency and Pb tolerance of radish. These findings would provide insight into molecular mechanism of Pb uptake and translocation in radish and facilitate development of low-Pb-content cultivars in root vegetable

  2. Transport, ultrastructural localization and distribution of chemical forms of lead in radish (Raphanus sativus L.

    Directory of Open Access Journals (Sweden)

    Yan eWang

    2015-05-01

    Full Text Available Lead (Pb, a ubiquitous but highly toxic heavy metal, is harmful to human health through various pathways including by ingestion of contaminated vegetables. Radish is a worldwide root vegetable crop with significant health and nutritional benefits. However, little is known about Pb translocation and distribution within radish plants after its uptake by the roots. In this study, Pb stress was induced using Pb(NO32 in hydroponic culture, aiming to characterize the transport, ultrastructural localization and distribution of chemical forms of Pb in different tissues of radish. The results showed that the majority of Pb (85.76–98.72% was retained in underground organs including lateral roots, root heads and taproot skins, while a small proportion of Pb was absorbed by root flesh (0.44–1.56% or transported to the shoot (1.28-14.24%. A large proportion of Pb (74.11–99.30% was integrated with undissolved Pb oxalate, protein and pectates forming Pb-phosphate complexes. Moreover, a low-Pb-accumulating line of radish showed a higher proportion of Pb in water-soluble form compared with a high-Pb-accumulating line. Subcellular distribution analysis showed that a large proportion of Pb was bound to cell wall fraction in lateral roots (71.08–80.40% and taproot skin (46.22–77.94%, while the leaves and roots had 28.36–39.37% and 27.35–46.51% of Pb stored in the soluble fraction, respectively. Furthermore, transmission electron microscopy (TEM revealed Pb precipitates in intercellular space, cell wall, plasma lemma and vacuoles. Fractionation results also showed the accumulation of Pb on the cell wall, intercellular space and vacuole, and low uptake of undissolved Pb oxalate, protein, pectates and Pb–phosphate complexes, which might be due to low transport efficiency and Pb tolerance of radish. These findings would provide insight into molecular mechanism of Pb uptake and translocation in radish and facilitate development of low

  3. Three-dimensional ultrastructural analyses of anterior pituitary gland expose spatial relationships between endocrine cell secretory granule localization and capillary distribution.

    Science.gov (United States)

    Yoshitomi, Munetake; Ohta, Keisuke; Kanazawa, Tomonoshin; Togo, Akinobu; Hirashima, Shingo; Uemura, Kei-Ichiro; Okayama, Satoko; Morioka, Motohiro; Nakamura, Kei-Ichiro

    2016-10-31

    Endocrine and endothelial cells of the anterior pituitary gland frequently make close appositions or contacts, and the secretory granules of each endocrine cell tend to accumulate at the perivascular regions, which is generally considered to facilitate secretory functions of these cells. However, three-dimensional relationships between the localization pattern of secretory granules and blood vessels are not fully understood. To define and characterize these spatial relationships, we used scanning electron microscopy (SEM) three-dimensional reconstruction method based on focused ion-beam slicing and scanning electron microscopy (FIB/SEM). Full three-dimensional cellular architectures of the anterior pituitary tissue at ultrastructural resolution revealed that about 70% of endocrine cells were in apposition to the endothelial cells, while almost 30% of endocrine cells were entirely isolated from perivascular space in the tissue. Our three-dimensional analyses also visualized the distribution pattern of secretory granules in individual endocrine cells, showing an accumulation of secretory granules in regions in close apposition to the blood vessels in many cases. However, secretory granules in cells isolated from the perivascular region tended to distribute uniformly in the cytoplasm of these cells. These data suggest that the cellular interactions between the endocrine and endothelial cells promote an uneven cytoplasmic distribution of the secretory granules.

  4. Ultrastructural immunocytochemical localization of chondroitin sulfate proteoglycan in Bruch's membrane of the rat

    DEFF Research Database (Denmark)

    Lin, W L; Essner, E; McCarthy, K J

    1992-01-01

    Two monoclonal antibodies (Mab 4D5 and 2D6) raised against the core protein of a basement membrane chondroitin sulfate proteoglycan from Reichert's membrane of the rat, were used for ultrastructural immunoperoxidase localization of this protein in Bruch's membrane of the rat. Immunoreactivity...

  5. Pancreatic PEComa: a case report with ultrastructural localization of HMB-45 within melanosomes.

    Science.gov (United States)

    Finzi, Giovanna; Micello, Donata; Wizemann, Giorgio; Sessa, Fausto; Capella, Carlo

    2012-04-01

    PEComas (perivascular epithelioid cell tumors) represent a group of mesenchymal neoplasms showing characteristic morphologic, immunohistochemical, ultrastructural, and genetic features. These neoplasms are usually considered benign, being often well circumscribed by a thin capsule and showing scarce atypia. However, in some cases, they show local invasion and multiple metastases and cause the patient's death. PEComas have been found in many locations, but only 7 cases have been described in the pancreas to date. Here, the authors report an additional case of this rare neoplasm and demonstrate the HMB-45 immunoreactivity of melanosomes or premelanosomes at the ultrastructural level.

  6. Histological and ultrastructural localization of antigen B in the metacestode of Taenia solium

    Energy Technology Data Exchange (ETDEWEB)

    Laclette, J.P.; Merchant, M.T.; Willms, K.

    1987-02-01

    The morphological localization of antigen B (AgB) in the tissues of the Taenia solium metacestode was studied by immunological and biochemical methods. Indirect immunofluorescence carried out on vibratome sections showed that AgB is widely distributed throughout the tissue. A more intense fluorescence was observed in the tegumentary cytons of the bladder wall and in the lumen of the spiral canal of the invaginated scolex. Ultrastructural analysis of larvae washed in PBS after dissection from meat and then incubated with rabbit antibodies against AgB, followed by peroxidase-labeled goat anti-rabbit IgG, did not exhibit electron-dense material on the external surface. Larvae fixed in glutaraldehyde immediately after dissection and exposed to the immunoperoxidase reagents did exhibit electron-dense material on microtriches, indicating that AgB is only loosely bound to the external surface. Crude extracts of surface-radioiodinated cysticerci analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) contained no labeled proteins with the molecular weight of AgB. Autoradiography of the immunoelectrophoretograms in which the crude extract was confronted with antibodies to AgB demonstrated that this antigen was not labeled, and therefore is not exposed on the tegumentary surface. The results suggest that AgB is synthesized by the tegumentary cytons of the parasite and secreted through the tegumental membrane into the host tissues and the lumen of the spiral canal.

  7. Histological and ultrastructural localization of antigen B in the metacestode of Taenia solium

    International Nuclear Information System (INIS)

    Laclette, J.P.; Merchant, M.T.; Willms, K.

    1987-01-01

    The morphological localization of antigen B (AgB) in the tissues of the Taenia solium metacestode was studied by immunological and biochemical methods. Indirect immunofluorescence carried out on vibratome sections showed that AgB is widely distributed throughout the tissue. A more intense fluorescence was observed in the tegumentary cytons of the bladder wall and in the lumen of the spiral canal of the invaginated scolex. Ultrastructural analysis of larvae washed in PBS after dissection from meat and then incubated with rabbit antibodies against AgB, followed by peroxidase-labeled goat anti-rabbit IgG, did not exhibit electron-dense material on the external surface. Larvae fixed in glutaraldehyde immediately after dissection and exposed to the immunoperoxidase reagents did exhibit electron-dense material on microtriches, indicating that AgB is only loosely bound to the external surface. Crude extracts of surface-radioiodinated cysticerci analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) contained no labeled proteins with the molecular weight of AgB. Autoradiography of the immunoelectrophoretograms in which the crude extract was confronted with antibodies to AgB demonstrated that this antigen was not labeled, and therefore is not exposed on the tegumentary surface. The results suggest that AgB is synthesized by the tegumentary cytons of the parasite and secreted through the tegumental membrane into the host tissues and the lumen of the spiral canal

  8. Ultrastructural localization of human papilloma virus by nonradioactive in situ hybridization on tissue of human cervical intraepithelial neoplasia

    DEFF Research Database (Denmark)

    Multhaupt, H A; Rafferty, P A; Warhol, M J

    1992-01-01

    BACKGROUND: A nonradioactive in situ hybridization was developed to localize human papilloma virus (HPV) at the ultrastructural level. EXPERIMENTAL DESIGN: Cervical biopsies from human uterine cervices clinically suspicious of condyloma were embedded in Lowicryl K4M at low temperature...

  9. ANF and exocrine pancreas: ultrastructural autoradiographic localization in acinar cells

    International Nuclear Information System (INIS)

    Chabot, J.G.; Morel, G.; Belles-Isles, M.; Jeandel, L.; Heisler, S.

    1988-01-01

    Atrial natriuretic factor (ANF) binding sites have been recently demonstrated to be present in exocrine pancreas by an in vitro autoradiographic approach. An autoradiographic study was carried out to identify the exocrine cells containing ANF binding sites and to monitor the fate of 125 I-labeled ANF in acinar cells after removal of pancreas at specific time intervals (1-30 min) after intravenous administration. At the light microscopic level, silver grains were found over acinar and centroacinar cells. Concomitant injection of an excess of unlabeled ANF inhibited the binding of labeled peptide by approximately 60%. At the electron microscopic level, the time-course study in acinar cells has revealed that of the cell compartments examined, plasma membrane, Golgi apparatus, mitochondria, and zymogen granules, the nucleus had distinct labeling patterns. Plasma membrane was maximally labeled 1 and 2 min after injection with 125 I-ANF. Golgi apparatus was significantly labeled from 2 to 30 min after injection, mitochondria from 1 to 30 min after injection, zymogen granules at 1 and 15 min, and the nucleus only at 30 min. The lysosomal compartment was not labeled during the 30-min observation period. These results suggest that after binding to the plasma membrane, ANF is rapidly internalized and distributed to the intracellular organelles as a function of time. Labeling of the zymogen granules suggests that they may bind ANF and that the atrial peptide may be secreted by acinar cells. The significance of association of radioactivity with mitochondria and nuclei remains to be elucidated but may represent intracellular sites of action of ANF complementary to those on plasma membranes

  10. Silicon in Imperata cylindrica (L.) P. Beauv: content, distribution, and ultrastructure.

    Science.gov (United States)

    Rufo, Lourdes; Franco, Alejandro; de la Fuente, Vicenta

    2014-07-01

    Silicon concentration, distribution, and ultrastructure of silicon deposits in the Poaceae Imperata cylindrica (L.) P. Beauv. have been studied. This grass, known for its medicinal uses and also for Fe hyperaccumulation and biomineralization capacities, showed a concentration of silicon of 13,705 ± 9,607 mg/kg dry weight. Silicon was found as an important constituent of cell walls of the epidermis of the whole plant. Silica deposits were found in silica bodies, endodermis, and different cells with silicon-collapsed lumen as bulliforms, cortical, and sclerenchyma cells. Transmission electron microscope observations of these deposits revealed an amorphous material of an ultrastructure similar to that previously reported in silica bodies of other Poaceae.

  11. Ultrastructural changes and the distribution of arabinogalactan proteins during somatic embryogenesis of banana (Musa spp. AAA cv. 'Yueyoukang 1').

    Science.gov (United States)

    Pan, Xiao; Yang, Xiao; Lin, Guimei; Zou, Ru; Chen, Houbin; Samaj, Jozef; Xu, Chunxiang

    2011-08-01

    A better understanding of somatic embryogenesis in banana (Musa spp.) may provide a practical way to improve regeneration of banana plants. In this study, we applied scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to visualize the ultrastructural changes during somatic embryogenesis of banana (Musa AAA cv. 'Yueyoukang 1'). We also used histological and immunohistochemical techniques with 16 monoclonal antibodies to study the spatial distribution and cellular/subcellular localization of different arabinogalactan protein (AGP) components of the cell wall during somatic embryogenesis. Histological study with periodic acid-Schiff staining documented diverse embryogenic stages from embryogenic cells (ECs) to the late embryos. SEM revealed a mesh-like structure on the surface of proembryos which represented an early structural marker of somatic embryogenesis. TEM showed that ECs were rich in juvenile mitochondria, endoplasmic reticulum and Golgi stacks. Cells in proembryos and early globular embryos resembled ECs, but they were more vacuolated, showed more regular nuclei and slightly more developed organelles. Immunocytochemical study revealed that the signal of most AGP epitopes was stronger in starch-rich cells when compared with typical ECs. The main AGP component in the extracellular matrix surface network of banana proembryos was the MAC204 epitope. Later, AGP immunolabelling patterns varied with the developmental stages of the embryos. These results about developmental regulation of AGP epitopes along with developmental changes in the ultrastructure of cells are providing new insights into the somatic embryogenesis of banana. Copyright © Physiologia Plantarum 2011.

  12. Effect of heat shock on ultrastructure and calcium distribution in Lavandula pinnata L. glandular trichomes.

    Science.gov (United States)

    Huang, S S; Kirchoff, B K; Liao, J P

    2013-02-01

    The effects of heat shock (HS) on the ultrastructure and calcium distribution of Lavandula pinnata secretory trichomes are examined using transmission electron microscopy and potassium antimonate precipitation. After 48-h HS at 40°C, plastids become distorted and lack stroma and osmiophilic deposits, the cristae of the mitochondria become indistinct, the endoplasmic reticulum acquires a chain-like appearance with ribosomes prominently attached to the lamellae, and the plasma and organelle membranes become distorted. Heat shock is associated with a decrease in calcium precipitates in the trichomes, while the number of precipitates increases in the mesophyll cells. Prolonged exposure to elevated calcium levels may be toxic to the mesophyll cells, while the lack of calcium in the glands cell may deprive them of the normal protective advantages of elevated calcium levels. The inequality in calcium distribution may result not only from uptake from the transpiration stream, but also from redistribution of calcium from the trichomes to the mesophyll cells.

  13. Ultrastructural Localization and Molecular Associations of HCV Capsid Protein in Jurkat T Cells

    Directory of Open Access Journals (Sweden)

    Cecilia Fernández-Ponce

    2018-01-01

    Full Text Available Hepatitis C virus core protein is a highly basic viral protein that multimerizes with itself to form the viral capsid. When expressed in CD4+ T lymphocytes, it can induce modifications in several essential cellular and biological networks. To shed light on the mechanisms underlying the alterations caused by the viral protein, we have analyzed HCV-core subcellular localization and its associations with host proteins in Jurkat T cells. In order to investigate the intracellular localization of Hepatitis C virus core protein, we have used a lentiviral system to transduce Jurkat T cells and subsequently localize the protein using immunoelectron microscopy techniques. We found that in Jurkat T cells, Hepatitis C virus core protein mostly localizes in the nucleus and specifically in the nucleolus. In addition, we performed pull-down assays combined with Mass Spectrometry Analysis, to identify proteins that associate with Hepatitis C virus core in Jurkat T cells. We found proteins such as NOLC1, PP1γ, ILF3, and C1QBP implicated in localization and/or traffic to the nucleolus. HCV-core associated proteins are implicated in RNA processing and RNA virus infection as well as in functions previously shown to be altered in Hepatitis C virus core expressing CD4+ T cells, such as cell cycle delay, decreased proliferation, and induction of a regulatory phenotype. Thus, in the current work, we show the ultrastructural localization of Hepatitis C virus core and the first profile of HCV core associated proteins in T cells, and we discuss the functions and interconnections of these proteins in molecular networks where relevant biological modifications have been described upon the expression of Hepatitis C virus core protein. Thereby, the current work constitutes a necessary step toward understanding the mechanisms underlying HCV core mediated alterations that had been described in relevant biological processes in CD4+ T cells.

  14. Distribution and ultrastructure of pigment cells in the skins of normal and albino adult turbot, Scophthalmus Maximus

    Institute of Scientific and Technical Information of China (English)

    GUO Huarong; HUANG Bing; QI Fei; ZHANG Shicui

    2007-01-01

    The distribution and ultrastructure of pigment cells in skins of normal and albino adult turbots were examined with transmission electron microscopy (TEM). Three types of pigment cells of melanophore, iridophore and xanthophore have been recognized in adult turbot skins. The skin color depends mainly on the amount and distribution of melanophore and iridophore, as xanthophore is quite rare. No pigment cells can be found in the epidermis of the skins. In the pigmented ocular skin of the turbot, melanophore and iridophore are usually co-localized in the dermis. This is quite different from the distribution in larvae skin. In albino and white blind skins of adult turbots, however, only iridophore monolayer still exists, while the melanophore monolayer disappears. This cytological evidence explains why the albino adult turbot, unlike its larvae, could never resume its body color no matter what environmental and nutritional conditions were provided. Endocytosis is quite active in the cellular membrane of the iridophore. This might be related to the formation of reflective platelet and stability of the iridophore.

  15. Localization of serotonin and ultrastructure of serotonergic neutrons in the nervous system of fasciola hepatica

    International Nuclear Information System (INIS)

    Huang Shile; Cheng Bing; Rong Yaofang

    1993-01-01

    Rabbits antisera were raised against an antigen prepared by coupling 5-HT to bovine serum albumin (BSA) using formaldehyde as a coupling reagent. The fresh adult Fasciola hepatica were fixed with 4% formaldehyde and sectioned on a cryostat. The sections were stained by indirect immunofluorescence technique. Abundant immunofluorescence specific for 5-HT was observed in ganglion cell bodies and their processes, the transverse commissure that connects two ganglia and longitudinal axes extending from the ganglia. Immuno-reactivity to 5-HT was also found in the nerve fibre innervating tegument, gut wall, the epithelium of testes or ovary, the musculature of uterus and ootype, etc. The ultrastructure of serotonergic neurons was visualized. As in other invertebrates, the serotonergic neutrons of Fasciola hepatica consisted of cell bodies, axons, synapses, herring bodies and neuromuscular junctions. The nerve cell bodies were aggregatively located in ganglia and many dispersed spherical granular vesicles were present in cytoplasm. The nerve axons branched out to the muscles forming synapses, where synaptic vesicles contained 5-HT dense-core granules were found. The distribution of 5-HT within the neurons strongly suggested that 5-HT was functioning as a neurotrasmitter in Fasciola hepatica

  16. Uptake, depuration, and distribution of selenium in Daphnia and its effects on survival and ultrastructure

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, T.W. (Pan American Univ., Edinburg, TX); Freeman, S.R.; Dumont, J.N.

    1980-01-01

    Selenium is an important essential nutritional trace element which has been shown to provide protection against certain other metal poisoning. However, it is a suspected carcinogen and teratogen. The uptake, depuration, and toxicity of selenium in Daphnia pulex have been examined. The LC/sub 50/ at 48 and 96 h for juvenile animals is 0.6 mg/L and 0.1 mg/L, respectively, and for adults it is 1.3 mg/L and 0.5 mg/L, respectively. Uptake in adult unfed animals is rapid, reaching a maximum at about 12 h, but depuration is slow. In fed animals, uptake is slower, reaching a maximum at 96 h, but initial depuration is followed by a slower prolonged loss. Localization in cells is primarily in the cytoplasmic compartment although evidence is presented which suggests nucleolar localization. Ultrastructural damage is detected by 16 h after exposure and is initially confined to the mitochondria. Dense deposits accumulate in the mitochondrial matrices. The nature of these deposits is unknown; they may represent a calcium- or phosphate-selenium complex. With time, the mitochondria degenerate. It is clear that relatively low concentrations of selenium are toxic to these aquatic organisms and render them incapable of survival in the natural environment. Concentrations higher than those lethal to Daphnia can be expected, at least in local areas, from the burning or conversion of fossil fuels.

  17. A locally adaptive normal distribution

    DEFF Research Database (Denmark)

    Arvanitidis, Georgios; Hansen, Lars Kai; Hauberg, Søren

    2016-01-01

    entropy distribution under the given metric. The underlying metric is, however, non-parametric. We develop a maximum likelihood algorithm to infer the distribution parameters that relies on a combination of gradient descent and Monte Carlo integration. We further extend the LAND to mixture models......The multivariate normal density is a monotonic function of the distance to the mean, and its ellipsoidal shape is due to the underlying Euclidean metric. We suggest to replace this metric with a locally adaptive, smoothly changing (Riemannian) metric that favors regions of high local density...

  18. Local distribution and franchising rights

    International Nuclear Information System (INIS)

    Penick, V.; Grant, R.; McKelvey, S.; Cramm, K.

    1998-01-01

    A summary of local distribution and franchising rights in Nova Scotia and New Brunswick is presented. The Gas Distribution Act calls for two distinct sets of regulations : broad regulations to be made by the provinces, and more technical procedural regulations to be made by the Utility and Review Board. The focus of this paper is on how municipalities will be affected by the regulations and how franchising within a local area will work. The overall objective is to ensure free competition in gas sales

  19. Local distribution and franchising rights

    Energy Technology Data Exchange (ETDEWEB)

    Penick, V. [McInnes, Cooper and Robertson, Halifax, NS (Canada); Grant, R.; McKelvey, S. [Stirling Scales, NB (Canada); Cramm, K. [Maritimes NRG, Halifax, NS (Canada)

    1998-12-31

    A summary of local distribution and franchising rights in Nova Scotia and New Brunswick is presented. The Gas Distribution Act calls for two distinct sets of regulations : broad regulations to be made by the provinces, and more technical procedural regulations to be made by the Utility and Review Board. The focus of this paper is on how municipalities will be affected by the regulations and how franchising within a local area will work. The overall objective is to ensure free competition in gas sales.

  20. Ultrastructural localization of actin and actin-binding proteins in the nucleus

    Czech Academy of Sciences Publication Activity Database

    Dingová, Hana; Fukalová, Jana; Maninová, Miloslava; Philimonenko, Vlada; Hozák, Pavel

    2009-01-01

    Roč. 131, č. 3 (2009), s. 425-434 ISSN 0948-6143 R&D Projects: GA MŠk LC545 Grant - others:MŠk(CZ) LC06063 Program:LC Institutional research plan: CEZ:AV0Z50520514 Keywords : nuclear actin * ultrastructure * actin–binding proteins Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.021, year: 2009

  1. Ultrastructural and immunohistochemical localization of plasma membrane Ca2+-ATPase 4 in Ca2+-transporting epithelia

    DEFF Research Database (Denmark)

    Alexander, R Todd; Beggs, Megan R; Zamani, Reza

    2015-01-01

    role in transcellular Ca(2+) flux and investigated the localization and regulation of Pmca4 in Ca(2+)-transporting epithelia. Using antibodies directed specifically against Pmca4, we found it expressed only in the smooth muscle layer of mouse and human intestine, while pan-specific Pmca antibodies...... the cortical thick ascending limbs, macula densa, and early distal tubules as well as smooth muscle layers surrounding renal vessels. In human kidney, a similar pattern of distribution was observed, with highest PMCA4 expression in NCC positive tubules. Electron microscopy demonstrated Pmca4 localization...... in distal nephron cells at both the basolateral membrane and intracellular perinuclear compartments, but not submembranous vesicles, suggesting rapid trafficking to the plasma membrane is unlikely to occur in vivo. Pmca4 expression was not altered by perturbations in Ca(2+) balance, pointing...

  2. Human skin basement membrane-associated heparan sulphate proteoglycan: distinctive differences in ultrastructural localization as a function of developmental age

    DEFF Research Database (Denmark)

    Horiguchi, Y; Fine, J D; Couchman, J R

    1991-01-01

    was identical to that observed in neonatal and adult human skin. These findings demonstrate that active remodelling of the dermo-epidermal junction occurs during at least the first two trimesters, and affects not only basement membrane-associated structures but also specific antigens.......Recent studies have demonstrated that skin basement membrane components are expressed within the dermo-epidermal junction in an orderly sequence during human foetal development. We have investigated the ultrastructural localization of basement membrane-related antigens in human foetal skin...... at different developmental ages using two monoclonal antibodies to a well-characterized basement membrane-associated heparan sulphate proteoglycan. A series of foetal skin specimens (range, 54-142 gestational days) were examined using an immunoperoxidase immunoelectron microscopic technique. In specimens...

  3. Ultrastructural autoradiographic localization of exogenous arachidonic acid in cultured endothelial and smooth muscle cells

    International Nuclear Information System (INIS)

    Tasca, S.I.; Galis, Z.

    1988-01-01

    The uptake and intracellular localization of exogenous arachidonic acid (AA) were investigated in cultured endothelial (EC) and smooth muscle cells (SMC) isolated from bovine aorta. The [ 14 C]AA uptake was assessed biochemically and by light and electron microscopic autoradiography. The highest values of silver grain surface density were associated with the mitochondria, lysosomes, and the Golgi apparatus of the EC. The grain linear density was greater on the nuclear envelope than on plasmalemma. On SMC, the grain density was highest on lipid droplets whereas the linear densities of the nuclear envelope and plasmalemma were similar. The share of each subcellular compartment in the AA distribution was estimated as the percentage of the individual silver grain count out of the total cell-associated radioactivity. The results showed that cytoplasm (including endoplasmic reticulum, ribosomes, and small vesicles) made the main contribution followed by the nucleus and at lower values by other organelles. These subcompartments may represent the intracellular sites from which AA could be mobilized for prostanoid synthesis by EC and SMC. (author)

  4. Ultrastructural localization of lead in Stigeoclonium tenue (chlorophyceae, ulotrichales) as demonstrated by cytochemical and x-ray microanalysis

    Energy Technology Data Exchange (ETDEWEB)

    Silverberg, B A

    1975-12-01

    Results of ultrastructural studies and TEM-X-ray microanalysis of the ulotrichalean alga Stigeoclonium tenue experimentally exposed to increasing concentrations of lead nitrate are presented. A fine-structural examination of the cells revealed that detectable amounts of lead (Pb) had entered the cytoplasm and could be recognized most easily as electron-dense precipitates localized on the cell wall and within the two large peripheral vacuoles. Dense deposits were never observed in mitochondria, plastids or nuclei. Pinocytotic vacuoles containing lead spheroids are removed endocytotically to the cytoplasmic vacuoles, rendering the Pb innocuous. The evidence suggests that the cell wall and vacuoles are important structures in maintaining a relatively low cytoplasmic concentration of lead, thereby reducing the toxic effects of lead ions on sensitive cellular functions. At high concentrations, ranging from 0.15 to 0.5 mg Pb/l, noticeable alterations in the fine structure of the chloroplast are evident. A method is described for the visualization of Pb deposits in fresh, chemically fixed and plastic-embedded material using a saturated solution of sodium rhodizonate.

  5. Ultrastructure of collagen fibers and distribution of extracellular matrix in the temporomandibular disk of the human fetus and adult.

    Science.gov (United States)

    Takahashi, H; Sato, I

    2001-12-01

    We quantitatively examined the distribution of these differences in extracellular matrices (collagen types I, III, and fibronectin) and elastic fibers under confocal laser scanning microscopy and electron scanning microscopy in terms of their contribution to the mechanics of the TMJ during development and in adults. Elastic fibers were found in the anterior and posterior bands in adults aged 40 years, and a few elastic fibers in the anterior band of the disk in adults aged 80 to 90 years. The extracellular matrix contents of the TMJ disk are shown in various detected levels in the anterior, intermediate, posterior bands of TMJ disk. During development, collagen fibers are arranged in a complex fashion from 28 weeks' gestation. These ultrastructures of the embryonic TMJ are resembled to that of adults aged the 40s, however the difference in extracellular matrix distribution found in embryonic stages and adults. They might reflect the differences in function between mastication and sucking or the changes in shape and form as results of functional disorders of the TMJ.

  6. Influence of different metal ions on the ultrastructure, biochemical properties, and protein localization of the K562 cell nuclear matrix.

    Science.gov (United States)

    Neri, L M; Bortul, R; Zweyer, M; Tabellini, G; Borgatti, P; Marchisio, M; Bareggi, R; Capitani, S; Martelli, A M

    1999-06-01

    The higher order of chromatin organization is thought to be determined by the nuclear matrix, a mainly proteinaceous structure that would act as a nucleoskeleton. The matrix is obtained from isolated nuclei by a series of extraction steps involving the use of high salt and nonspecific nucleases, which remove chromatin and other loosely bound components. It is currently under debate whether these structures, isolated in vitro by unphysiological extraction buffers, correspond to a nucleoskeleton existing in vivo. In most cell types investigated, the nuclear matrix does not spontaneously resist these extractions steps; rather, it must be stabilized before the application of extracting agents. In this study nuclei, isolated from K562 human erythroleukemia cells, were stabilized by incubation with different metal ions (Ca2+, Cu2+, Zn2+, Cd2+), and the matrix was obtained by extraction with 2 M NaCl. By means of ultrastructural analysis of the resulting structures, we determined that, except for Ca2+, all the other metals induced a stabilization of the matrix, which retained the inner fibrogranular network and residual nucleoli. The biochemical composition, analyzed by two-dimensional gel electrophoresis separation, exhibited a distinct matrix polypeptide pattern, characteristic of each type of stabilizing ion employed. We also investigated to what extent metal ions could maintain in the final structures the original distribution of three inner matrix components, i.e. NuMA, topoisomerase IIalpha, and RNP. Confocal microscopy analysis showed that only NuMa, and, to a lesser extent, topoisomerase IIalpha, were unaffected by stabilization with divalent ions. On the contrary, the fluorescent RNP patterns detected in the resulting matrices were always disarranged, irrespective of the stabilization procedure. These results indicate that several metal ions are powerful stabilizing agents of the nuclear matrix prepared from K562 erythroleukemia cells and also strengthen the

  7. Ultrastructural localization of uranium biosorption in Penicillium digitatum by stem x-ray microanalysis

    International Nuclear Information System (INIS)

    Galun, M.; Galun, E.

    1987-01-01

    When Penicillium digitatum Saccardo cultures are exposed to aqueous solutions containing soluble uranium salts, considerable amounts of this element are accumulated in the fungal mycelium. The accumulated uranium is retained after thorough rinsing with distilled water but is removed by alkali carbonate solutions. Analysis of thick sections (0.5 μm) of the fungal hyphae with TEM, after incubation in UO 2 Cl 2 solutions of varying concentrations under both light and dark conditions, revealed conspicuous crystal-like deposits in UO 2 Cl 2 -exposed hyphae, but none in the control hyphae. Thick sections were necessary for crystal visualization. Using energy-dispersive X-ray analysis, uranium was detected as the only heavy element in these crystals. Uranium crystal biosorption was localized on the outside surface of the hyphal cell wall (following short exposures to relatively low uranium concentrations) or inside the cell wall (following long exposure to relatively high uranium concentrations). In some cases, crystal-like deposits of uranium salts were located on the outside surface as well as inside the cell. (author)

  8. Restructuring local distribution services: Possibilities and limitations

    Energy Technology Data Exchange (ETDEWEB)

    Duann, D.J.

    1994-08-01

    The restructuring of local distribution services is now the focus of the natural gas industry. It is the last major step in the ``reconstitution`` of the natural gas industry and a critical clement in realizing the full benefits of regulatory and market reforms that already have taken place in the wellhead and interstate markets. It could also be the most important regulatory initiative for most end-use customers because they are affected directly by the costs and reliability of distribution services. Several factors contribute to the current emphasis on distribution service restructuring. They include the unbundling and restructuring of upstream markets, a realization of the limitations of supply-side options (such as gas procurement oversight), and the increased diversity and volatility of gas demand facing local distribution companies. Local distribution service is not one but a series of activities that start with commodity gas procurement and extend to transportation, load balancing, storage, and metering and billing of services provided. There are also considerable differences in the economies of scale and scope associated with these various activities. Thus, a mixture of supply arrangements (such as a competitive market or a monopoly) is required for the most efficient delivery of local distribution services. A distinction must be made between the supply of commodity gas and the provision of a bundled distribution service. This distinction and identification of the best supply arrangements for various distribution service components are the most critical factors in developing appropriate restructuring policies. For most state public utility commissions the criteria for service restructuring should include pursuing the economies of scale and scope in gas distribution, differentiating and matching gas service reliability and quality with customer requirements, and controlling costs associated with the search, negotiation, and contracting of gas services.

  9. Mapping the subcellular distribution of biomolecules at the ultrastructural level by ion microscopy.

    Science.gov (United States)

    Galle, P; Escaig, F; Dantin, F; Zhang, L

    1996-05-01

    Analytical ion microscopy, a method proposed and developed in 1960 by Casting and Slodzian at the Orsay University (France), makes it possible to obtain easily and rapidly analytical images representing the distribution in a tissue section of elements or isotopes (beginning from the three isotopes of hydrogen until to transuranic elements), even when these elements or isotopes are at a trace concentration of 1 ppm or less. This method has been applied to study the subcellular distribution of different varieties of biomolecules. The subcellular location of these molecules can be easily determined when the molecules contain in their structures a specific atom such as fluorine, iodine, bromine or platinum, what is the case of many pharmaceutical drugs. In this situation, the distribution of these specific atoms can be considered as representative of the distribution of the corresponding molecule. In other cases, the molecules must be labelled with an isotope which may be either radioactive or stable. Recent developments in ion microscopy allow the obtention of their chemical images at ultra structural level. In this paper we present the results obtained with the prototype of a new Scanning Ion Microscope used for the study of the intracellular distribution of different varieties of molecules: glucocorticoids, estrogens, pharmaceutical drugs and pyrimidine analogues.

  10. Distribution costs -- the cost of local delivery

    International Nuclear Information System (INIS)

    Winger, N.; Zarnett, P.; Carr, J.

    2000-01-01

    Most of the power transmission system in the province of Ontario is owned and operated as a regulated monopoly by Ontario Hydro Services Company (OHSC). Local distribution systems deliver to end-users from bulk supply points within a service territory. OHSC distributes to approximately one million, mostly rural customers, while the approximately 250 municipal utilities together serve about two million, mostly urban customers. Under the Energy Competition Act of 1998 local distribution companies will face some new challenges, including unbundled billing systems, a broader range of distribution costs, increased costs, made up of corporate taxes or payments in lieu of taxes and added costs for regulatory affairs. The consultants provide a detailed discussion of the components of distribution costs, the three components of the typical budget process (capital expenditures, (CAPEX), operating and maintenance (O and M) and administration and corporate (GA and C), a summary of some typical distribution costs in Ontario, and the estimated impacts of the Energy Competition Act (ECA) compliance on charges and rates. Various mitigation strategies are also reviewed. Among these are joint ventures by local distribution companies to reduce ECA compliance costs, re-examination of controllable costs, temporary reduction of the allowable return on equity (ROE) by 50 per cent, and/or reducing the competitive transition charge (CTC). It is estimated that either one of these two reductions could eliminate the full amount of the five to seven per cent uplift in delivered energy service costs. The conclusion of the consultants is that local distribution delivery charges will make up a greater proportion of end-user cost in the future than it has in the past. An increase to customers of about five per cent is expected when the competitive electricity market opens and unbundled billing begins. The cost increase could be mitigated by a combination of actions that would be needed for about

  11. Composition and distribution of elements and ultrastructural topography of a human cardiac calculus.

    Science.gov (United States)

    Cheng, Ching-Li; Chang, Hsiao-Huang; Huang, Pei-Jung; Chu, Yu-Ting; Lin, Shan-Yang

    2013-04-01

    Trace elements (TEs) may contribute to the formation of calculi or stones or be involved in the aetiopathogenesis of stone diseases. The compositions and spatial distribution of elements from the inner nucleus to outer crust of the cardiac calculus were investigated by energy-dispersive X-ray fluorescence (EDXRF) spectrometer. The surface topograph, distribution map of elements, elemental and chemical compositions were also determined by environmental scanning electron microscope (ESEM)-energy-dispersive X-ray (EDX) analysis. Twenty-five elements were identifiable from 18 positions on the cardiac calculus by EDXRF spectrometer, in which the highest concentrations of toxic TEs (Ni, Pt, Hg, Sn, Pb, W, Au, Al, Si) and higher levels of essential TEs (Ca, Sr, Cr, P) were detected. A moderate positive Pearson's correlation between TEs concentrations of Mg, Ca or P and location differences from centre to periphery in the cardiac calculus was observed. A positive correlation was also found for Ca/Zn and Ca/Cu, indicating the gradual increase of calcium concentration from inner nucleus to outer crust of cardiac calculus. The drop-like nodules/crystals on the surface of petrous part of cardiac calculus were observed from ESEM analysis. ESEM-EDX analysis determined the calculus to be predominantly composed of calcium hydroxyapatite and cholesterol, as indicated by the petrous surface and drop-like nodules/crystals, respectively. This composition was confirmed using a portable Raman analyser. The spatial distribution analysis indicated a gradual increase in Mg, P and Ca concentrations from the inner nucleus to the outer crust of the cardiac calculus. The major chemical compositions of calcium hydroxyapatite and cholesterol were detected on this cardiac calculus.

  12. Shaped input distributions for structural damage localization

    DEFF Research Database (Denmark)

    Ulriksen, Martin Dalgaard; Bernal, Dionisio; Damkilde, Lars

    2018-01-01

    localization method is cast that operates on the premise of shaping inputs—whose spatial distribution is fixed—by use of a model, such that these inputs, in one structural subdomain at a time, suppress certain steady-state vibration quantities (depending on the type of damage one seeks to interrogate for......). Accordingly, damage is localized when the vibration signature induced by the shaped inputs in the damaged state corresponds to that in the reference state, hereby implying that the approach does not point directly to damage. Instead, it operates with interrogation based on postulated damage patterns...

  13. Distributed formation tracking using local coordinate systems

    DEFF Research Database (Denmark)

    Yang, Qingkai; Cao, Ming; Garcia de Marina, Hector

    2018-01-01

    This paper studies the formation tracking problem for multi-agent systems, for which a distributed estimator–controller scheme is designed relying only on the agents’ local coordinate systems such that the centroid of the controlled formation tracks a given trajectory. By introducing a gradient...... descent term into the estimator, the explicit knowledge of the bound of the agents’ speed is not necessary in contrast to existing works, and each agent is able to compute the centroid of the whole formation in finite time. Then, based on the centroid estimation, a distributed control algorithm...

  14. [Tooth macromorphological and ultrastructural analysis of osteological material from the medieval locality of St. Panteleimon Church in Nis].

    Science.gov (United States)

    Mitić, Nadica; Mitić, Aleksandar; Mitić, Vladimir; Savić, Vojin; Nikolić, Marija

    2010-01-01

    Analysis of macromorphological and ultrastructural tooth characteristics of osteological material from the medieval site of St. Pantaleimon Church in Nis provides us with insight on the life, nutrition and habits of medieval population, as well as the structure and composition of their teeth. The aim of this research, based on the tooth inspection of skeletal remains from the medieval site of St. Pantaleimon Church in Nis, was to analyze macromorphological characteristics, ultrastructure of the dental tissue of maxillary and mandibular molars, canines and incisors, as well as their chemical composition. Macromorphological and ultrastructural analysis of the dental tissue of osteological material dating from the 12th century included 1312 teeth with advanced abrasion. Macromorphological changes were detected by using a dental mirror, probe and radiography. After irrigation, the teeth were prepared using the standard procedure and analyzed by scanning electronic microscopy (JEOL-JSM-5300). Chemical analysis was done by expanded downscaling (EDS) method for Mg, P, Ca. The analysis detected second degree abrasions of all teeth in individuals aged 20-25 years. Third and fourth degree abrasions of teeth were detected in individuals aged over 40 years. Ultrastructural analysis showed a complete obliteration of dentin tubules and pulp of the lower incisors, the apposition of intratubular dentin inside the tubules, as well as extensive deformity and loss of dentin structure on molars with preserved pulp volume and nerve fiber calcification. The calcification of nerve fibers showed that the formation of intratubular dentin was proportional with the biological potential of pulp and the degree of abrasion, and inversely proportional with the size of dentin surface. Chemical analysis showed that in the analyzed teeth Ca composition was slightly lower than that in the control group, P composition was almost identical, while Mg composition was multiply increased in comparison to

  15. Fluorescence Localization and Comparative Ultrastructural Study of Periplocoside NW from Periploca sepium Bunge in the Midgut of the Oriental Amyworm, Mythimna separata Walker (Lepidoptera: Noctuidae

    Directory of Open Access Journals (Sweden)

    Mingxing Feng

    2014-05-01

    Full Text Available Periplocoside NW (PSNW is a novel insecticidal compound isolated from the root bark of Periploca sepium Bunge and has potent stomach toxicity against some insect pests. Previous studies showed that the Mythimna separata larva is sensitive to PSNW, but the Agrotis ispilon larva is insensitive. In this study, preliminary target localization on the midgut of M. separata larvae was conducted via a fluorescence labeling technique. A comparative ultrastructural study on the effects of PSNW on the midguts of M. separata and A. ispilon larvae was performed. Symptom observation results showed that typical stomach toxicity was induced by PSNW in M. separata larvae. Fluorescence localization results showed that PSNW binds to the midgut cells of M. separata larvae. Ultrastructure observations showed destruction of the microvilli, organelle, and cytomembrane in the midgut cells of M. separata larvae, whereas no obvious changes were observed in midgut cells of A. ispilon larvae. These results were consistent with the insecticidal activity of PSNW. Therefore, PSNW might act on the midgut tissues of the insects, and one or more binding sites of PSNW may exist in M. separata larvae midgut cell cytomembranes.

  16. Expression dynamics and ultrastructural localization of epitope-tagged Abutilon mosaic virus nuclear shuttle and movement proteins in Nicotiana benthamiana cells

    International Nuclear Information System (INIS)

    Kleinow, Tatjana; Tanwir, Fariha; Kocher, Cornelia; Krenz, Bjoern; Wege, Christina; Jeske, Holger

    2009-01-01

    The geminivirus Abutilon mosaic virus (AbMV) encodes two proteins which are essential for viral spread within plants. The nuclear shuttle protein (NSP) transfers viral DNA between the nucleus and cytoplasm, whereas the movement protein (MP) facilitates transport between cells through plasmodesmata and long-distance via phloem. An inducible overexpression system for epitope-tagged NSP and MP in plants yielded unprecedented amounts of both proteins. Western blots revealed extensive posttranslational modification and truncation for MP, but not for NSP. Ultrastructural examination of Nicotiana benthamiana tissues showed characteristic nucleopathic alterations, including fibrillar rings, when epitope-tagged NSP and MP were simultaneously expressed in leaves locally infected with an AbMV DNA A in which the coat protein gene was replaced by a green fluorescent protein encoding gene. Immunogold labelling localized NSP in the nucleoplasm and in the fibrillar rings. MP appeared at the cell periphery, probably the plasma membrane, and plasmodesmata.

  17. Short-term influence of Cu, Zn, Ni and Cd excess on metabolism, ultrastructure and distribution of elements in lichen Xanthoria parietina (L.) Th. Fr.

    Science.gov (United States)

    Piovár, J; Weidinger, M; Bačkor, M; Bačkorová, M; Lichtscheidl, I

    2017-11-01

    Lichens are symbiotic organisms that are very sensitive to heavy metal pollution. However, there is little evidence of how heavy metal pollution affects the physiological status, ultrastructural changes and distribution of elements in the layers of lichen thalli. For this purpose we simulated metal pollution to lichens and studied its impact on Xanthoria parietina. Thalli were treated with the heavy metals Cu, Zn, Ni, Cd in the form of sulfates at concentrations of 100µM and 500µM during 24, 48 and 72h. Untreated lichens served as controls. We assessed the status of physiological parameters (fluorescence and integrity of chlorophyll a, content of soluble proteins and ergosterol), ultrastructural changes, especially to the photobiont, and the distribution of elements in the layers of thalli in relation to treatment with heavy metals. We found positive correlations between the content of all tested heavy metals and the physiological response. We assessed the toxicity of the selected metals as follows: Cd >= Cu >= Ni > Zn, based on the effects on the photobiont layer in the lichen thallus and physiological measurements. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Regional expression and ultrastructural localization of EphA7 in the hippocampus and cerebellum of adult rat.

    Science.gov (United States)

    Amegandjin, Clara A; Jammow, Wafaa; Laforest, Sylvie; Riad, Mustapha; Baharnoori, Moogeh; Badeaux, Frédérique; DesGroseillers, Luc; Murai, Keith K; Pasquale, Elena B; Drolet, Guy; Doucet, Guy

    2016-08-15

    EphA7 is expressed in the adult central nervous system (CNS), where its roles are yet poorly defined. We mapped its distribution using in situ hybridization (ISH) and immunohistochemistry (IHC) combined with light (LM) and electron microscopy (EM) in adult rat and mouse brain. The strongest ISH signal was in the hippocampal pyramidal and granule cell layers. Moderate levels were detected in habenula, striatum, amygdala, the cingulate, piriform and entorhinal cortex, and in cerebellum, notably the Purkinje cell layer. The IHC signal distribution was consistent with ISH results, with transport of the protein to processes, as exemplified in the hippocampal neuropil layers and weakly stained pyramidal cell layers. In contrast, in the cerebellum, the Purkinje cell bodies were the most strongly immunolabeled elements. EM localized the cell surface-expression of EphA7 essentially in postsynaptic densities (PSDs) of dendritic spines and shafts, and on some astrocytic leaflets, in both hippocampus and cerebellum. Perikaryal and dendritic labeling was mostly intracellular, associated with the synthetic and trafficking machineries. Immunopositive vesicles were also observed in axons and axon terminals. Quantitative analysis in EM showed significant differences in the frequency of labeled elements between regions. Notably, labeled dendrites were ∼3-5 times less frequent in cerebellum than in hippocampus, but they were individually endowed with ∼10-40 times higher frequencies of PSDs, on their shafts and spines. The cell surface localization of EphA7, being preferentially in PSDs, and in perisynaptic astrocytic leaflets, provides morphologic evidence that EphA7 plays key roles in adult CNS synaptic maintenance, plasticity, or function. J. Comp. Neurol. 524:2462-2478, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  19. Ultrastructural changes in nucleoli and fibrillar centers under the effect of local ultraviolet microbeam irradiation of interphase culture cells

    International Nuclear Information System (INIS)

    Zatsepina, O.V.; Voronkova, L.N.; Sakharov, V.N.; Chentsov, Y.S.

    1989-01-01

    As shown previously, ultraviolet (uv) microbeam irradiation of one of the two mature nucleoli within an interphase cell nucleus causes significant diminution and inactivation of the irradiated nucleolus and compensatory growth and activation of the nonirradiated one. In the present work we describe the results of an ultrastructural study of this phenomenon. The changes in the nucleoli were examined by means of complete series of ultrathin sections obtained from seven irradiated pig kidney cells. The compensatory hypertrophy of the nonirradiated nucleoli is shown to be accompanied by a nearly twofold increase in the number of fibrillar centers (FCs) and by a decrease in their linear dimensions compared with the control cells of the same ploidy. In the degraded nucleoli the number of FCs decreases, but their dimensions increase. Ultraviolet microbeam irradiation causes dramatic diminution of the dense fibrillar component within the irradiated nucleoli as well. The nucleolar capacity for compensatory hypertrophy indicates that in addition to active ribosomal genes, mature nucleoli also contain silent genes capable of being activated under extreme conditions to sustain the required level of rRNA synthesis. It is assumed that activation of latent ribosomal genes is accompanied by FC fragmentation without a considerable increase in their total volume per cell

  20. Local search in physical distribution management

    NARCIS (Netherlands)

    G.A.P. Kindervater (Gerard); M.W.P. Savelsbergh (Martin)

    1992-01-01

    textabstractPhysical distribution management presents a variety of decision making problems at three levels of strategic, tactical and operational planning. The importance of effective and efficient distribution management is evident from its associated costs. Physical distribution management at the

  1. Ultrastructural observations on giardiasis in a mouse model. II. Endosymbiosis and organelle distribution in Giardia muris and Giardia lamblia.

    Science.gov (United States)

    Nemanic, P C; Owen, R L; Stevens, D P; Mueller, J C

    1979-08-01

    Ultrastructural observations of Giardia muris in a mouse model revealed endosymbiotic microbes not previously reported in Giardia. Endosymbionts 240--360 nm wide, 600--1,400 nm long, and with an internal structure similar to that of bacilli were not seen entering Giardia but were found and appeared to divide within Giardia. No evidence was found of digestion of the endosymbionts by the giardia host in either the trophozoite or the cyst form. Endosymbionts were concentrated centrally around the nuclear area and were uncommon in peripheral feeding regions. The same cellular organelles seen in G. muris were found in Giardia lamblia from human jejunal biopsy material, but no endosymbionts were identified in G. lamblia trophozoites from the seven patients examined. Endosymbionts within Giardia may be found to alter trophozoite pathogenicity, metabolism, range of infectivity, antigenic surface characteristics, and host specificity, as they do in other protozoa.

  2. Pricing local distribution services in a competitive market

    International Nuclear Information System (INIS)

    Duann, D.J.

    1995-12-01

    Unbundling and restructuring of local distribution services is the focus of the natural gas industry. As a result of regulatory reforms, a competitive local distribution market has emerged, and the validity of traditional cost-based regulation is being questioned. One alternative is to completely unbundle local distribution services and transform the local distribution company into a common carrier for intrastate transportation services. Three kinds of alternative pricing mechanisms are examined. For firm intrastate transportation services, cost-based pricing is the preferred method unless it can be shown that a competitive secondary market can be established and maintained. Pricing interruptible transportation capacity is discussed

  3. A Scalable Local Algorithm for Distributed Multivariate Regression

    Data.gov (United States)

    National Aeronautics and Space Administration — This paper offers a local distributed algorithm for multivariate regression in large peer-to-peer environments. The algorithm can be used for distributed...

  4. An Efficient Local Algorithm for Distributed Multivariate Regression

    Data.gov (United States)

    National Aeronautics and Space Administration — This paper offers a local distributed algorithm for multivariate regression in large peer-to-peer environments. The algorithm is designed for distributed...

  5. ARG3.1/ARC expression in hippocampal dentate gyrus astrocytes: ultrastructural evidence and co-localization with glial fibrillary acidic protein

    Czech Academy of Sciences Publication Activity Database

    Rodríguez, J.J.; Davies, H.A.; Errington, M.L.; Verkhratsky, Alexei; Bliss, T.V.P.; Stewart, M.G.

    2008-01-01

    Roč. 12, č. 2 (2008), s. 671-678 ISSN 1582-1838 Institutional research plan: CEZ:AV0Z50390512 Keywords : Hippocampus * Ultrastructure * Glia Subject RIV: FH - Neurology Impact factor: 5.114, year: 2008

  6. Semi-quantitative ultrastructural analysis of the localization and neuropeptide content of gonadotropin releasing hormone nerve terminals in the median eminence throughout the estrous cycle of the rat.

    Science.gov (United States)

    Prevot, V; Dutoit, S; Croix, D; Tramu, G; Beauvillain, J C

    1998-05-01

    The ultrastructural appearance of gonadotropin releasing hormone-immunoreactive elements was studied in the external zone of the median eminence of adult female Wistar rats. On the one hand, the purpose of the study was to determine the distribution of gonadotropin releasing hormone terminals towards the parenchymatous basal lamina at the level of hypothalamo-hypophyseal portal vessels, throughout the estrous cycle. On the other hand, we have semi-quantified the gonadotropin releasing hormone content in nerve terminals or preterminals during this physiological condition. A morphometric study was coupled to a colloidal 15 mn gold postembedding immunocytochemistry procedure. Animals were killed at 09.00 on diestrus II, 0.900, 10.00, 13.00, 17.00 and 18.00 on proestrus and 09.00 on estrus (n = 4-8 rats/group). A preliminary light microscopic study was carried out to identify an antero-posterior part of median eminence strongly immunostained by anti-gonadotropin releasing hormone antibodies but which was, in addition, easily spotted. This last condition was necessary to make a good comparison between each animal. Contacts between gonadotropin releasing hormone nerve terminals and the basal lamina were observed only the day of proestrus. Such contacts, however, were rare and in the great majority of cases, gonadotropin releasing hormone terminals are separated from basal lamina by tanycytic end feet. The morphometric analysis showed no significant variation in average distance between gonadotropin releasing hormone terminals and capillaries throughout the estrous cycle. Consequently, it did not appear that a large neuroglial plasticity exists during the estrous cycle. However, the observation of contacts only on proestrus together with some ultrastructural images evoke the possibility of a slight plasticity. The semi-quantitative results show that the content of gonadotropin releasing hormone in the nerve endings presented two peaks on proestrus: one at 09.00 (23 +/- 5

  7. Ultra-structural cell distribution of the melanoma marker iodobenzamide: improved potentiality of SIMS imaging in life sciences

    Directory of Open Access Journals (Sweden)

    Papon Janine

    2004-04-01

    Full Text Available Abstract Background Analytical imaging by secondary ion mass spectrometry (SIMS provides images representative of the distribution of a specific ion within a sample surface. For the last fifteen years, concerted collaborative research to design a new ion microprobe with high technical standards in both mass and lateral resolution as well as in sensitivity has led to the CAMECA NanoSims 50, recently introduced onto the market. This instrument has decisive capabilities, which allow biological applications of SIMS microscopy at a level previously inaccessible. Its potential is illustrated here by the demonstration of the specific affinity of a melanoma marker for melanin. This finding is of great importance for the diagnosis and/or treatment of malignant melanoma, a tumour whose worldwide incidence is continuously growing. Methods The characteristics of the instrument are briefly described and an example of application is given. This example deals with the intracellular localization of an iodo-benzamide used as a diagnostic tool for the scintigraphic detection of melanic cells (e.g. metastasis of malignant melanoma. B16 melanoma cells were injected intravenously to C57BL6/J1/co mice. Multiple B16 melanoma colonies developed in the lungs of treated animals within three weeks. Iodobenzamide was injected intravenously in tumour bearing mice six hours before sacrifice. Small pieces of lung were prepared for SIMS analysis. Results Mouse lung B16 melanoma colonies were observed with high lateral resolution. Cyanide ions gave "histological" images of the cell, representative of the distribution of C and N containing molecules (e.g. proteins, nucleic acids, melanin, etc. while phosphorus ions are mainly produced by nucleic acids. Iodine was detected only in melanosomes, confirming the specific affinity of the drug for melanin. No drug was found in normal lung tissue. Conclusion This study demonstrates the potential of SIMS microscopy, which allows the

  8. Automated leak localization performance without detailed demand distribution data

    NARCIS (Netherlands)

    Moors, Janneke; Scholten, L.; van der Hoek, J.P.; den Besten, J.

    2018-01-01

    Automatic leak localization has been suggested to reduce the time and personnel efforts needed to localize
    (small) leaks. Yet, the available methods require a detailed demand distribution model for successful
    calibration and good leak localization performance. The main aim of this work was

  9. Binding-energy distribution and dephasing of localized biexcitons

    DEFF Research Database (Denmark)

    Langbein, Wolfgang Werner; Hvam, Jørn Märcher; Umlauff, M.

    1997-01-01

    We report on the binding energy and dephasing of localized biexciton states in narrow ZnSe multiple quantum wells. The measured binding-energy distribution of the localized biexcitons shows a width of 2.2 meV centered at 8.5 meV, and is fairly independent of the exciton localization energy. In fo...

  10. Distribution and ultrastructure of neurons in opossum piriform cortex displaying immunoreactivity to GABA and GAD and high-affinity tritiated GABA uptake

    International Nuclear Information System (INIS)

    Haberly, L.B.; Hansen, D.J.; Feig, S.L.; Presto, S.

    1987-01-01

    GABAergic neurons have been identified in the piriform cortex of the opossum at light and electron microscopic levels by immunocytochemical localization of GABA and the GABA-synthesizing enzyme glutamic acid decarboxylase and by autoradiographic visualization of high-affinity 3 H-GABA uptake. Four major neuron populations have been distinguished on the basis of soma size, shape, and segregation at specific depths and locations: large horizontal cells in layer Ia of the anterior piriform cortex, small globular cells with thin dendrites concentrated in layers Ib and II of the posterior piriform cortex, and multipolar and fusiform cells concentrated in the deep part of layer III in anterior and posterior parts of the piriform cortex and the subjacent endopiriform nucleus. All four populations were well visualized with both antisera, but the large layer Ia horizontal cells displayed only very light 3 H-GABA uptake, thus suggesting a lack of local axon collaterals or lack of high-affinity GABA uptake sites. The large, ultrastructurally distinctive somata of layer Ia horizontal cells receive a very small number of symmetrical synapses; the thin, axonlike dendrites of small globular cells are exclusively postsynaptic and receive large numbers of both symmetrical and asymmetrical synapses, in contrast to somata which receive a small number of both types; and the deep multipolar and fusiform cells receive a highly variable number of symmetrical and asymmetrical synapses on somata and proximal dendrites. Labeled puncta of axon terminal dimensions were found in large numbers in the neuropil surrounding pyramidal cell somata in layer II and in the endopiriform nucleus. Moderately large numbers of labeled puncta were found in layer I at the depth of pyramidal cell apical dendrites with greater numbers in layer Ia at the depth of distal apical segments than in layer Ib

  11. New power distribution challenges at the local scale

    International Nuclear Information System (INIS)

    Delage, Marion; Cadoux, Florent; Petit, Marc

    2016-01-01

    Distribution grids are facing the connection of both more and more variable distributed generation sources and new loads such as electric vehicles. Then distribution grid operators evolve to distribution system operators (DSOs) with new flexibilities (power control of distributed energy sources) to complete their traditional planning and operation tools. In the future, additional distributed resources could be used, such as demand response and storage. DSOs are becoming actors of a global electrical system where power balancing must be ensured at the European level with local constraints (congestion and voltage), and with power flows from transmission to distribution grids but also inside the distribution grid or from distribution to transmission. Sensors and data availability are key issues to enable these transformations. This paper defines some general concerns and present European issues with illustrations from the French electrical system. (authors)

  12. Optical distribution of local oscillators in future telecommunication satellite payloads

    Science.gov (United States)

    Benazet, Benoît; Sotom, Michel; Maignan, Michel; Berthon, Jacques

    2017-11-01

    The distribution of high spectral purity reference signals over optical fibre in future telecommunication satellite payloads is presented. Several types of applications are considered, including the distribution of a reference frequency at 10 MHz (Ultra-Stable Reference Oscillator) as well as the distribution of a radiofrequency oscillator around 800 MHz (Master Local Oscillator). The results of both experimental and theoretical studies are reported. In order to meet phase noise requirements for the USRO distribution, the use of an optimised receiver circuit based on an optically synchronised oscillator is investigated. Finally, the optical distribution of microwave local oscillators at frequencies exceeding 20 GHz is described. Such a scheme paves the way to more advanced sub-systems involving optical frequency-mixing and optical transmission of microwave signals, with applications to multiple-beam active antennas.

  13. Error Control in Distributed Node Self-Localization

    Directory of Open Access Journals (Sweden)

    Ying Zhang

    2008-03-01

    Full Text Available Location information of nodes in an ad hoc sensor network is essential to many tasks such as routing, cooperative sensing, and service delivery. Distributed node self-localization is lightweight and requires little communication overhead, but often suffers from the adverse effects of error propagation. Unlike other localization papers which focus on designing elaborate localization algorithms, this paper takes a different perspective, focusing on the error propagation problem, addressing questions such as where localization error comes from and how it propagates from node to node. To prevent error from propagating and accumulating, we develop an error-control mechanism based on characterization of node uncertainties and discrimination between neighboring nodes. The error-control mechanism uses only local knowledge and is fully decentralized. Simulation results have shown that the active selection strategy significantly mitigates the effect of error propagation for both range and directional sensors. It greatly improves localization accuracy and robustness.

  14. Adenosine A2A Receptor in the Monkey Basal Ganglia: Ultrastructural Localization and Colocalization With the Metabotropic Glutamate Receptor 5 in the Striatum

    OpenAIRE

    Bogenpohl, James W.; Ritter, Stefanie L.; Hall, Randy A.; Smith, Yoland

    2012-01-01

    The adenosine A2A receptor (A2AR) is a potential drug target for the treatment of Parkinson’s disease and other neurological disorders. In rodents, the therapeutic efficacy of A2AR modulation is improved by concomitant modulation of the metabotropic glutamate receptor 5 (mGluR5). To elucidate the anatomical substrate(s) through which these therapeutic benefits could be mediated, pre-embedding electron microscopy immunohistochemistry was used to conduct a detailed, quantitative ultrastructural...

  15. Distribution and ultrastructure of interstitial cells of Cajal in the mouse colon, using antibodies to Kit and Kit(W-lacZ) mice

    DEFF Research Database (Denmark)

    Vanderwinden, J M; Rumessen, J J; Bernex, F

    2000-01-01

    kinase receptor Kit as a marker. Sections and whole mounts were studied by confocal microscopy after double immunofluorescence with specific antibodies. The ultrastructure of Kit-expressing cells was examined by electron microcopy in KitW-lacz/+ transgenic mice, which carry the lacz gene inserted...

  16. Food availability and accessibility in the local food distribution ...

    African Journals Online (AJOL)

    Objectives: The objective was to understand the local food distribution system in Avian Park, with a focus on food availability and accessibility. Study design: This was a quantitative food store survey that employed semi-structured interviews and focus group discussions. Setting: The study was conducted in Avian Park, ...

  17. Gas-leak localization using distributed ultrasonic sensors

    Science.gov (United States)

    Huseynov, Javid; Baliga, Shankar; Dillencourt, Michael; Bic, Lubomir; Bagherzadeh, Nader

    2009-03-01

    We propose an ultrasonic gas leak localization system based on a distributed network of sensors. The system deploys highly sensitive miniature Micro-Electro-Mechanical Systems (MEMS) microphones and uses a suite of energy-decay (ED) and time-delay of arrival (TDOA) algorithms for localizing a source of a gas leak. Statistical tools such as the maximum likelihood (ML) and the least squares (LS) estimators are used for approximating the source location when closed-form solutions fail in the presence of ambient background nuisance and inherent electronic noise. The proposed localization algorithms were implemented and tested using a Java-based simulation platform connected to four or more distributed MEMS microphones observing a broadband nitrogen leak from an orifice. The performance of centralized and decentralized algorithms under ED and TDOA schemes is analyzed and compared in terms of communication overhead and accuracy in presence of additive white Gaussian noise (AWGN).

  18. Locally Minimum Storage Regenerating Codes in Distributed Cloud Storage Systems

    Institute of Scientific and Technical Information of China (English)

    Jing Wang; Wei Luo; Wei Liang; Xiangyang Liu; Xiaodai Dong

    2017-01-01

    In distributed cloud storage sys-tems, inevitably there exist multiple node fail-ures at the same time. The existing methods of regenerating codes, including minimum storage regenerating (MSR) codes and mini-mum bandwidth regenerating (MBR) codes, are mainly to repair one single or several failed nodes, unable to meet the repair need of distributed cloud storage systems. In this paper, we present locally minimum storage re-generating (LMSR) codes to recover multiple failed nodes at the same time. Specifically, the nodes in distributed cloud storage systems are divided into multiple local groups, and in each local group (4, 2) or (5, 3) MSR codes are constructed. Moreover, the grouping method of storage nodes and the repairing process of failed nodes in local groups are studied. The-oretical analysis shows that LMSR codes can achieve the same storage overhead as MSR codes. Furthermore, we verify by means of simulation that, compared with MSR codes, LMSR codes can reduce the repair bandwidth and disk I/O overhead effectively.

  19. Local Information as a Resource in Distributed Quantum Systems

    Science.gov (United States)

    Horodecki, Michał; Horodecki, Karol; Horodecki, Paweł; Horodecki, Ryszard; Oppenheim, Jonathan; Sende, Aditi; Sen, Ujjwal

    2003-03-01

    A new paradigm for distributed quantum systems where information is a valuable resource is developed. After finding a unique measure for information, we construct a scheme for its manipulation in analogy with entanglement theory. In this scheme, instead of maximally entangled states, two parties distill local states. We show that, surprisingly, the main tools of entanglement theory are general enough to work in this opposite scheme. Up to plausible assumptions, we show that the amount of information that must be lost during the protocol of concentration of local information can be expressed as the relative entropy distance from some special set of states.

  20. Climate Controls AM Fungal Distributions from Global to Local Scales

    Science.gov (United States)

    Kivlin, S. N.; Hawkes, C.; Muscarella, R.; Treseder, K. K.; Kazenel, M.; Lynn, J.; Rudgers, J.

    2016-12-01

    Arbuscular mycorrhizal (AM) fungi have key functions in terrestrial biogeochemical processes; thus, determining the relative importance of climate, edaphic factors, and plant community composition on their geographic distributions can improve predictions of their sensitivity to global change. Local adaptation by AM fungi to plant hosts, soil nutrients, and climate suggests that all of these factors may control fungal geographic distributions, but their relative importance is unknown. We created species distribution models for 142 AM fungal taxa at the global scale with data from GenBank. We compared climate variables (BioClim and soil moisture), edaphic variables (phosphorus, carbon, pH, and clay content), and plant variables using model selection on models with (1) all variables, (2) climatic variables only (including soil moisture) and (3) resource-related variables only (all other soil parameters and NPP) using the MaxEnt algorithm evaluated with ENMEval. We also evaluated whether drivers of AM fungal distributions were phylogenetically conserved. To test whether global correlates of AM fungal distributions were reflected at local scales, we then surveyed AM fungi in nine plant hosts along three elevation gradients in the Upper Gunnison Basin, Colorado, USA. At the global scale, the distributions of 55% of AM fungal taxa were affected by both climate and soil resources, whereas 16% were only affected by climate and 29% were only affected by soil resources. Even for AM fungi that were affected by both climate and resources, the effects of climatic variables nearly always outweighed those of resources. Soil moisture and isothermality were the main climatic and NPP and soil carbon the main resource related factors influencing AM fungal distributions. Distributions of closely related AM fungal taxa were similarly affected by climate, but not by resources. Local scale surveys of AM fungi across elevations confirmed that climate was a key driver of AM fungal

  1. Localizing Value of Pain Distribution Patterns in Cervical Spondylosis

    OpenAIRE

    Bunyaratavej, Krishnapundha; Montriwiwatnchai, Peerapong; Siwanuwatn, Rungsak; Khaoroptham, Surachai

    2015-01-01

    Study Design Prospective observational study. Purpose To investigate the value of pain distribution in localizing appropriate surgical levels in patients with cervical spondylosis. Overview of Literature Previous studies have investigated the value of pain drawings in its correlation with various features in degenerative spine diseases including surgical outcome, magnetic resonance imaging findings, discographic study, and psychogenic issues. However, there is no previous study on the value o...

  2. Local viscosity distribution in bifurcating microfluidic blood flows

    Science.gov (United States)

    Kaliviotis, E.; Sherwood, J. M.; Balabani, S.

    2018-03-01

    The red blood cell (RBC) aggregation phenomenon is majorly responsible for the non-Newtonian nature of blood, influencing the blood flow characteristics in the microvasculature. Of considerable interest is the behaviour of the fluid at the bifurcating regions. In vitro experiments, using microchannels, have shown that RBC aggregation, at certain flow conditions, affects the bluntness and skewness of the velocity profile, the local RBC concentration, and the cell-depleted layer at the channel walls. In addition, the developed RBC aggregates appear unevenly distributed in the outlets of these channels depending on their spatial distribution in the feeding branch, and on the flow conditions in the outlet branches. In the present work, constitutive equations of blood viscosity, from earlier work of the authors, are applied to flows in a T-type bifurcating microchannel to examine the local viscosity characteristics. Viscosity maps are derived for various flow distributions in the outlet branches of the channel, and the location of maximum viscosity magnitude is obtained. The viscosity does not appear significantly elevated in the branches of lower flow rate as would be expected on the basis of the low shear therein, and the maximum magnitude appears in the vicinity of the junction, and towards the side of the outlet branch with the higher flow rate. The study demonstrates that in the branches of lower flow rate, the local viscosity is also low, helping us to explain why the effects of physiological red blood cell aggregation have no adverse effects in terms of in vivo vascular resistance.

  3. Molecular characterization, tissue distribution, and ultrastructural localization of adipokinetic hormones in the CNS of the firebug Pyrrhocoris apterus (Heteroptera, Insecta)

    Czech Academy of Sciences Publication Activity Database

    Kodrík, Dalibor; Stašková, Tereza; Jedličková, V.; Weyda, F.; Závodská, Radka; Pflegerová, Jitka

    2015-01-01

    Roč. 210, Jan 1 (2015), s. 1-11 ISSN 0016-6480 R&D Projects: GA ČR GA14-07172S Institutional support: RVO:60077344 Keywords : AKH * pre-pro-hormone * insect brain Subject RIV: ED - Physiology Impact factor: 2.667, year: 2015 http://www.sciencedirect.com/science/article/pii/S0016648014004158

  4. The ultrastructure of interphase nucleoli of PK-cells during their compensatory hypertrophy and degradation as a result of local UV microirradiation

    International Nuclear Information System (INIS)

    Zatsepina, O.V.; Voronkova, L.N.; Sakharov, V.N.; Chentsov, Yu.S.; AN SSSR, Moscow

    1988-01-01

    The ultrastructure of degraded and hypertrophic nucleoli in pig embryo kidney cells was studied using serial superfine sections. It is shown that nucleolus compensator hypertrophy is accompanied by a sufficient increase of the number of fibrillary centers (FC) and by a reduction of their linear dimensions as compared to the control; in degraded nucleoli the FC number is reduced and their dimensions are increased. On the whole the degraded nucleolus structural changes after UV-micro-irradiation correspond to the changes caused by an action of other rRNA synthesis inhibitors known. The nucleolus ability to compensator hypertropy shows that apart from operating ribosome genes, latent p-gens, which cn be activated under extreme conditions to keep the necessary rRNA synthesis level, exist in a cell. An assumption is made that such an activation is accompanied by ''fragmentation'' of pre-existing FC into smaller and more multiple ones

  5. Risk analysis for a local gas distribution network

    International Nuclear Information System (INIS)

    Peters, J.W.

    1991-01-01

    Cost control and service reliability are popular topics when discussing strategic issues facing local distribution companies (LDCs) in the 1990s. The ability to provide secure and uninterrupted gas service is crucial for growth and company image, both with the public and regulatory agencies. At the same time, the industry is facing unprecedented competition from alternate fuels, and cost control is essential for maintaining a competitive edge in the market. On the surface, it would appear that cost control and service reliability are contradictory terms. Improvement in service reliability should cost something, or does it? Risk analysis can provide the answer from a distribution design perspective. From a gas distribution engineer's perspective, projects such as loops, backfeeds and even valve placement are designed to reduce, minimize and/or eliminate potential customer outages. These projects improve service reliability by acting as backups should a failure occur on a component of the distribution network. These contingency projects are cost-effective but their longterm benefit or true value is under question. Their purpose is to maintain supply to an area in the distribution network in the event of a failure somewhere else. Two phrases, potential customer outages and in the event of failure, identify uncertainty

  6. Higher-order momentum distributions and locally affine LDDMM registration

    DEFF Research Database (Denmark)

    Sommer, Stefan Horst; Nielsen, Mads; Darkner, Sune

    2013-01-01

    description of affine transformations and subsequent compact description of non-translational movement in a globally nonrigid deformation. The resulting representation contains directly interpretable information from both mathematical and modeling perspectives. We develop the mathematical construction......To achieve sparse parametrizations that allow intuitive analysis, we aim to represent deformation with a basis containing interpretable elements, and we wish to use elements that have the description capacity to represent the deformation compactly. To accomplish this, we introduce in this paper...... higher-order momentum distributions in the large deformation diffeomorphic metric mapping (LDDMM) registration framework. While the zeroth-order moments previously used in LDDMM only describe local displacement, the first-order momenta that are proposed here represent a basis that allows local...

  7. Localizing value of pain distribution patterns in cervical spondylosis.

    Science.gov (United States)

    Bunyaratavej, Krishnapundha; Montriwiwatnchai, Peerapong; Siwanuwatn, Rungsak; Khaoroptham, Surachai

    2015-04-01

    Prospective observational study. To investigate the value of pain distribution in localizing appropriate surgical levels in patients with cervical spondylosis. Previous studies have investigated the value of pain drawings in its correlation with various features in degenerative spine diseases including surgical outcome, magnetic resonance imaging findings, discographic study, and psychogenic issues. However, there is no previous study on the value of pain drawings in identifying symptomatic levels for the surgery in cervical spondylosis. The study collected data from patients with cervical spondylosis who underwent surgical treatment between August 2009 and July 2012. Pain diagrams drawn separately by each patient and physician were collected. Pain distribution patterns among various levels of surgery were analyzed by the chi-square test. Agreement between different pairs of data, including pain diagrams drawn by each patient and physician, intra-examiner agreement on interpretation of pain diagrams, inter-examiner agreement on interpretation of pain diagrams, interpretation of pain diagram by examiners and actual surgery, was analyzed by Kappa statistics. The study group consisted of 19 men and 28 women with an average age of 55.2 years. Average duration of symptoms was 16.8 months. There was no difference in the pain distribution pattern at any level of surgery. The agreement between pain diagram drawn by each patient and physician was moderate. Intra-examiner agreement was moderate. There was slight agreement of inter-examiners, examiners versus actual surgery. Pain distribution pattern by itself has limited value in identifying surgical levels in patients with cervical spondylosis.

  8. Ultrastructural study of chromoplast components rich in glycolipids

    OpenAIRE

    Wrischer, Mercedes; Prebeg, Tatjana; Magnus, Volker; Ljubešić, Nikola

    2001-01-01

    A cytochemical method for the ultrastructural localization of glycolipids, performed on thin sections, was used in the study of tubular chromoplasts. The method gave clear pictures of structures that contained glycolipids, while other chemical constituents were not stained. The method was tested on two flowers (Impatients noli-tangere L. and Thunbergia alata Boj. ex Sims) containing different types of tubular chromoplasts. The ultrastructure and mode of development of the two types of tubu...

  9. Forecasting an invasive species’ distribution with global distribution data, local data, and physiological information

    Science.gov (United States)

    Jarnevich, Catherine S.; Young, Nicholas E.; Talbert, Marian; Talbert, Colin

    2018-01-01

    Understanding invasive species distributions and potential invasions often requires broad‐scale information on the environmental tolerances of the species. Further, resource managers are often faced with knowing these broad‐scale relationships as well as nuanced environmental factors related to their landscape that influence where an invasive species occurs and potentially could occur. Using invasive buffelgrass (Cenchrus ciliaris), we developed global models and local models for Saguaro National Park, Arizona, USA, based on location records and literature on physiological tolerances to environmental factors to investigate whether environmental relationships of a species at a global scale are also important at local scales. In addition to correlative models with five commonly used algorithms, we also developed a model using a priori user‐defined relationships between occurrence and environmental characteristics based on a literature review. All correlative models at both scales performed well based on statistical evaluations. The user‐defined curves closely matched those produced by the correlative models, indicating that the correlative models may be capturing mechanisms driving the distribution of buffelgrass. Given climate projections for the region, both global and local models indicate that conditions at Saguaro National Park may become more suitable for buffelgrass. Combining global and local data with correlative models and physiological information provided a holistic approach to forecasting invasive species distributions.

  10. Mesoscale characterization of local property distributions in heterogeneous electrodes

    Science.gov (United States)

    Hsu, Tim; Epting, William K.; Mahbub, Rubayyat; Nuhfer, Noel T.; Bhattacharya, Sudip; Lei, Yinkai; Miller, Herbert M.; Ohodnicki, Paul R.; Gerdes, Kirk R.; Abernathy, Harry W.; Hackett, Gregory A.; Rollett, Anthony D.; De Graef, Marc; Litster, Shawn; Salvador, Paul A.

    2018-05-01

    The performance of electrochemical devices depends on the three-dimensional (3D) distributions of microstructural features in their electrodes. Several mature methods exist to characterize 3D microstructures over the microscale (tens of microns), which are useful in understanding homogeneous electrodes. However, methods that capture mesoscale (hundreds of microns) volumes at appropriate resolution (tens of nm) are lacking, though they are needed to understand more common, less ideal electrodes. Using serial sectioning with a Xe plasma focused ion beam combined with scanning electron microscopy (Xe PFIB-SEM), two commercial solid oxide fuel cell (SOFC) electrodes are reconstructed over volumes of 126 × 73 × 12.5 and 124 × 110 × 8 μm3 with a resolution on the order of ≈ 503 nm3. The mesoscale distributions of microscale structural features are quantified and both microscale and mesoscale inhomogeneities are found. We analyze the origin of inhomogeneity over different length scales by comparing experimental and synthetic microstructures, generated with different particle size distributions, with such synthetic microstructures capturing well the high-frequency heterogeneity. Effective medium theory models indicate that significant mesoscale variations in local electrochemical activity are expected throughout such electrodes. These methods offer improved understanding of the performance of complex electrodes in energy conversion devices.

  11. Sex differences in hippocampal estradiol-induced N-methyl-D-aspartic acid binding and ultrastructural localization of estrogen receptor-alpha.

    Science.gov (United States)

    Romeo, Russell D; McCarthy, J Brian; Wang, Athena; Milner, Teresa A; McEwen, Bruce S

    2005-01-01

    Estradiol increases dendritic spine density and synaptogenesis in the CA1 region of the female hippocampus. This effect is specific to females, as estradiol-treated males fail to show increases in hippocampal spine density. Estradiol-induced spinogenesis in the female is dependent upon upregulation of the N-methyl-D-aspartic acid (NMDA) receptor as well as on non-nuclear estrogen receptors (ER), including those found in dendrites. Thus, in the male, the inability of estradiol to induce spinogenesis may be related to a failure of estradiol to increase hippocampal NMDA receptors as well as a paucity of dendritic ER. In the first experiment, we sought to investigate this possibility by assessing NMDA receptor binding, using [(3)H]-glutamate autoradiography, in estradiol-treated males and females. We found that while estradiol increases NMDA binding in gonadectomized females, estradiol fails to modulate NMDA binding in gonadectomized males. To further investigate sex differences in the hippocampus, we conducted a second separate, but related, ultrastructural study in which we quantified ERalpha-immunoreactivity (ERalpha-ir) in neuronal profiles in the CA1 region of the hippocampus in intact males and females in diestrus and proestrus. Consistent with previous reports in the female, we found ERalpha-ir in several extranuclear sites including dendrites, spines, terminals and axons. Statistical analyses revealed that females in proestrus had a 114.3% increase in ERalpha-labeled dendritic spines compared to females in diestrus and intact males. Taken together, these studies suggest that both the ability of estrogen to increase NMDA binding in the hippocampus and the presence of ERalpha in dendritic spines may contribute to the observed sex difference in estradiol-induced hippocampal spinogenesis. Copyright (c) 2005 S. Karger AG, Basel.

  12. Fiber optic distributed temperature sensing for fire source localization

    Science.gov (United States)

    Sun, Miao; Tang, Yuquan; Yang, Shuang; Sigrist, Markus W.; Li, Jun; Dong, Fengzhong

    2017-08-01

    A method for localizing a fire source based on a distributed temperature sensor system is proposed. Two sections of optical fibers were placed orthogonally to each other as the sensing elements. A tray of alcohol was lit to act as a fire outbreak in a cabinet with an uneven ceiling to simulate a real scene of fire. Experiments were carried out to demonstrate the feasibility of the method. Rather large fluctuations and systematic errors with respect to predicting the exact room coordinates of the fire source caused by the uneven ceiling were observed. Two mathematical methods (smoothing recorded temperature curves and finding temperature peak positions) to improve the prediction accuracy are presented, and the experimental results indicate that the fluctuation ranges and systematic errors are significantly reduced. The proposed scheme is simple and appears reliable enough to locate a fire source in large spaces.

  13. Functional brain networks develop from a "local to distributed" organization.

    Directory of Open Access Journals (Sweden)

    Damien A Fair

    2009-05-01

    Full Text Available The mature human brain is organized into a collection of specialized functional networks that flexibly interact to support various cognitive functions. Studies of development often attempt to identify the organizing principles that guide the maturation of these functional networks. In this report, we combine resting state functional connectivity MRI (rs-fcMRI, graph analysis, community detection, and spring-embedding visualization techniques to analyze four separate networks defined in earlier studies. As we have previously reported, we find, across development, a trend toward 'segregation' (a general decrease in correlation strength between regions close in anatomical space and 'integration' (an increased correlation strength between selected regions distant in space. The generalization of these earlier trends across multiple networks suggests that this is a general developmental principle for changes in functional connectivity that would extend to large-scale graph theoretic analyses of large-scale brain networks. Communities in children are predominantly arranged by anatomical proximity, while communities in adults predominantly reflect functional relationships, as defined from adult fMRI studies. In sum, over development, the organization of multiple functional networks shifts from a local anatomical emphasis in children to a more "distributed" architecture in young adults. We argue that this "local to distributed" developmental characterization has important implications for understanding the development of neural systems underlying cognition. Further, graph metrics (e.g., clustering coefficients and average path lengths are similar in child and adult graphs, with both showing "small-world"-like properties, while community detection by modularity optimization reveals stable communities within the graphs that are clearly different between young children and young adults. These observations suggest that early school age children and adults

  14. Functional brain networks develop from a "local to distributed" organization.

    Science.gov (United States)

    Fair, Damien A; Cohen, Alexander L; Power, Jonathan D; Dosenbach, Nico U F; Church, Jessica A; Miezin, Francis M; Schlaggar, Bradley L; Petersen, Steven E

    2009-05-01

    The mature human brain is organized into a collection of specialized functional networks that flexibly interact to support various cognitive functions. Studies of development often attempt to identify the organizing principles that guide the maturation of these functional networks. In this report, we combine resting state functional connectivity MRI (rs-fcMRI), graph analysis, community detection, and spring-embedding visualization techniques to analyze four separate networks defined in earlier studies. As we have previously reported, we find, across development, a trend toward 'segregation' (a general decrease in correlation strength) between regions close in anatomical space and 'integration' (an increased correlation strength) between selected regions distant in space. The generalization of these earlier trends across multiple networks suggests that this is a general developmental principle for changes in functional connectivity that would extend to large-scale graph theoretic analyses of large-scale brain networks. Communities in children are predominantly arranged by anatomical proximity, while communities in adults predominantly reflect functional relationships, as defined from adult fMRI studies. In sum, over development, the organization of multiple functional networks shifts from a local anatomical emphasis in children to a more "distributed" architecture in young adults. We argue that this "local to distributed" developmental characterization has important implications for understanding the development of neural systems underlying cognition. Further, graph metrics (e.g., clustering coefficients and average path lengths) are similar in child and adult graphs, with both showing "small-world"-like properties, while community detection by modularity optimization reveals stable communities within the graphs that are clearly different between young children and young adults. These observations suggest that early school age children and adults both have

  15. Subspace Learning via Local Probability Distribution for Hyperspectral Image Classification

    Directory of Open Access Journals (Sweden)

    Huiwu Luo

    2015-01-01

    Full Text Available The computational procedure of hyperspectral image (HSI is extremely complex, not only due to the high dimensional information, but also due to the highly correlated data structure. The need of effective processing and analyzing of HSI has met many difficulties. It has been evidenced that dimensionality reduction has been found to be a powerful tool for high dimensional data analysis. Local Fisher’s liner discriminant analysis (LFDA is an effective method to treat HSI processing. In this paper, a novel approach, called PD-LFDA, is proposed to overcome the weakness of LFDA. PD-LFDA emphasizes the probability distribution (PD in LFDA, where the maximum distance is replaced with local variance for the construction of weight matrix and the class prior probability is applied to compute the affinity matrix. The proposed approach increases the discriminant ability of the transformed features in low dimensional space. Experimental results on Indian Pines 1992 data indicate that the proposed approach significantly outperforms the traditional alternatives.

  16. Power Consumption Evaluation of Distributed Computing Network Considering Traffic Locality

    Science.gov (United States)

    Ogawa, Yukio; Hasegawa, Go; Murata, Masayuki

    When computing resources are consolidated in a few huge data centers, a massive amount of data is transferred to each data center over a wide area network (WAN). This results in increased power consumption in the WAN. A distributed computing network (DCN), such as a content delivery network, can reduce the traffic from/to the data center, thereby decreasing the power consumed in the WAN. In this paper, we focus on the energy-saving aspect of the DCN and evaluate its effectiveness, especially considering traffic locality, i.e., the amount of traffic related to the geographical vicinity. We first formulate the problem of optimizing the DCN power consumption and describe the DCN in detail. Then, numerical evaluations show that, when there is strong traffic locality and the router has ideal energy proportionality, the system's power consumption is reduced to about 50% of the power consumed in the case where a DCN is not used; moreover, this advantage becomes even larger (up to about 30%) when the data center is located farthest from the center of the network topology.

  17. Distributed SLAM Using Improved Particle Filter for Mobile Robot Localization

    Directory of Open Access Journals (Sweden)

    Fujun Pei

    2014-01-01

    Full Text Available The distributed SLAM system has a similar estimation performance and requires only one-fifth of the computation time compared with centralized particle filter. However, particle impoverishment is inevitably because of the random particles prediction and resampling applied in generic particle filter, especially in SLAM problem that involves a large number of dimensions. In this paper, particle filter use in distributed SLAM was improved in two aspects. First, we improved the important function of the local filters in particle filter. The adaptive values were used to replace a set of constants in the computational process of importance function, which improved the robustness of the particle filter. Second, an information fusion method was proposed by mixing the innovation method and the number of effective particles method, which combined the advantages of these two methods. And this paper extends the previously known convergence results for particle filter to prove that improved particle filter converges to the optimal filter in mean square as the number of particles goes to infinity. The experiment results show that the proposed algorithm improved the virtue of the DPF-SLAM system in isolate faults and enabled the system to have a better tolerance and robustness.

  18. Constraining particle dark matter using local galaxy distribution

    International Nuclear Information System (INIS)

    Ando, Shin’ichiro; Ishiwata, Koji

    2016-01-01

    It has been long discussed that cosmic rays may contain signals of dark matter. In the last couple of years an anomaly of cosmic-ray positrons has drawn a lot of attentions, and recently an excess in cosmic-ray anti-proton has been reported by AMS-02 collaboration. Both excesses may indicate towards decaying or annihilating dark matter with a mass of around 1–10 TeV. In this article we study the gamma rays from dark matter and constraints from cross correlations with distribution of galaxies, particularly in a local volume. We find that gamma rays due to inverse-Compton process have large intensity, and hence they give stringent constraints on dark matter scenarios in the TeV scale mass regime. Taking the recent developments in modeling astrophysical gamma-ray sources as well as comprehensive possibilities of the final state products of dark matter decay or annihilation into account, we show that the parameter regions of decaying dark matter that are suggested to explain the excesses are excluded. We also discuss the constrains on annihilating scenarios.

  19. Spatial Distribution Of Local Markets In Ife North Local Government Area

    Directory of Open Access Journals (Sweden)

    OMOTOYE-OMISORE Oyelola

    2015-08-01

    Full Text Available Researches have been carried out in the past by several authors concerning agricultural marketing without the use of geospatial techniques. This research therefore is meant to show the efficacy of Geographical Information System GIS in local market distribution. The role of market place as a man-made feature where goods and services are exchanged for the purpose of satisfying human needs cannot be overemphasized especially in the general development of villages and towns. This study shows the effectiveness of GIS without the use of metrics method to determine the agricultural market locations and closeness of the markets in Ife North Local Government area. Different kinds of people bring their goods from far and near villages for sale and sustainability in this research both primary and secondary data were collected. Primary data includes the use of Global Positioning System GPS receiver to collect coordinate points of the existing markets. It also involves verbal interview with market women. While secondary data were sourced from administrative maps and satellite images of the area of study it was geo-referenced and digitized. Arc Map was used to run average nearest neighbor analysis. Base on the analysis performed the major constraint facing the market people is poor road network which affect majority of the farmers in transporting their goods from remote villages as indicated in this study. As a result new markets sites were proposed with the use of geospatial techniques for easy accessibility.

  20. Data Locality via Coordinated Caching for Distributed Processing

    Science.gov (United States)

    Fischer, M.; Kuehn, E.; Giffels, M.; Jung, C.

    2016-10-01

    To enable data locality, we have developed an approach of adding coordinated caches to existing compute clusters. Since the data stored locally is volatile and selected dynamically, only a fraction of local storage space is required. Our approach allows to freely select the degree at which data locality is provided. It may be used to work in conjunction with large network bandwidths, providing only highly used data to reduce peak loads. Alternatively, local storage may be scaled up to perform data analysis even with low network bandwidth. To prove the applicability of our approach, we have developed a prototype implementing all required functionality. It integrates seamlessly into batch systems, requiring practically no adjustments by users. We have now been actively using this prototype on a test cluster for HEP analyses. Specifically, it has been integral to our jet energy calibration analyses for CMS during run 2. The system has proven to be easily usable, while providing substantial performance improvements. Since confirming the applicability for our use case, we have investigated the design in a more general way. Simulations show that many infrastructure setups can benefit from our approach. For example, it may enable us to dynamically provide data locality in opportunistic cloud resources. The experience we have gained from our prototype enables us to realistically assess the feasibility for general production use.

  1. Distribution of MN blood group types in local populations in ...

    Indian Academy of Sciences (India)

    lation, which measures how many people come into the local population, was then .... 1986). In contrast, the Japanese have only 30.9%. (Furuhata et al. ... also came from nearby towns, all of which, Isabela included, are composed of ...

  2. Age and sex distribution of blindness in Ahoada East Local ...

    African Journals Online (AJOL)

    Background: Differences exist in the impact of blindness by age and sex; the overall risk of death being higher for blind males than females. Aim: To describe the age and sex differences among the blind in Ahoada-East Local Government Area (LGA) of Rivers State, Nigeria. Methods: Age and sex data were analyzed for 24 ...

  3. Global and local consistencies in distributed fault diagnosis for discrete-event systems

    NARCIS (Netherlands)

    Su, R.; Wonham, W.M.

    2005-01-01

    In this paper, we present a unified framework for distributed diagnosis. We first introduce the concepts of global and local consistency in terms of supremal global and local supports, then present two distributed diagnosis problems based on them. After that, we provide algorithms to achieve

  4. Supervisor Localization: A Top-Down Approach to Distributed Control of Discrete-Event Systems

    International Nuclear Information System (INIS)

    Cai, K.; Wonham, W. M.

    2009-01-01

    A purely distributed control paradigm is proposed for discrete-event systems (DES). In contrast to control by one or more external supervisors, distributed control aims to design built-in strategies for individual agents. First a distributed optimal nonblocking control problem is formulated. To solve it, a top-down localization procedure is developed which systematically decomposes an external supervisor into local controllers while preserving optimality and nonblockingness. An efficient localization algorithm is provided to carry out the computation, and an automated guided vehicles (AGV) example presented for illustration. Finally, the 'easiest' and 'hardest' boundary cases of localization are discussed.

  5. Mapping local and global variability in plant trait distributions

    Energy Technology Data Exchange (ETDEWEB)

    Butler, Ethan E.; Datta, Abhirup; Flores-Moreno, Habacuc; Chen, Ming; Wythers, Kirk R.; Fazayeli, Farideh; Banerjee, Arindam; Atkin, Owen K.; Kattge, Jens; Amiaud, Bernard; Blonder, Benjamin; Boenisch, Gerhard; Bond-Lamberty, Ben; Brown, Kerry A.; Byun, Chaeho; Campetella, Giandiego; Cerabolini, Bruno E. L.; Cornelissen, Johannes H. C.; Craine, Joseph M.; Craven, Dylan; de Vries, Franciska T.; Díaz, Sandra; Domingues, Tomas F.; Forey, Estelle; González-Melo, Andrés; Gross, Nicolas; Han, Wenxuan; Hattingh, Wesley N.; Hickler, Thomas; Jansen, Steven; Kramer, Koen; Kraft, Nathan J. B.; Kurokawa, Hiroko; Laughlin, Daniel C.; Meir, Patrick; Minden, Vanessa; Niinemets, Ülo; Onoda, Yusuke; Peñuelas, Josep; Read, Quentin; Sack, Lawren; Schamp, Brandon; Soudzilovskaia, Nadejda A.; Spasojevic, Marko J.; Sosinski, Enio; Thornton, Peter E.; Valladares, Fernando; van Bodegom, Peter M.; Williams, Mathew; Wirth, Christian; Reich, Peter B.

    2017-12-01

    Accurate trait-environment relationships and global maps of plant trait distributions represent a needed stepping stone in global biogeography and are critical constraints of key parameters for land models. Here, we use a global data set of plant traits to map trait distributions closely coupled to photosynthesis and foliar respiration: specific leaf area (SLA), and dry mass-based concentrations of leaf nitrogen (Nm) and phosphorus (Pm); We propose two models to extrapolate geographically sparse point data to continuous spatial surfaces. The first is a categorical model using species mean trait values, categorized into plant functional types (PFTs) and extrapolating to PFT occurrence ranges identified by remote sensing. The second is a Bayesian spatial model that incorporates information about PFT, location and environmental covariates to estimate trait distributions. Both models are further stratified by varying the number of PFTs; The performance of the models was evaluated based on their explanatory and predictive ability. The Bayesian spatial model leveraging the largest number of PFTs produced the best maps; The interpolation of full trait distributions enables a wider diversity of vegetation to be represented across the land surface. These maps may be used as input to Earth System Models and to evaluate other estimates of functional diversity.

  6. Distribution of local anesthetics between aqueous and liposome phases

    Czech Academy of Sciences Publication Activity Database

    Ruokonen, S. K.; Duša, Filip; Rantamäki, A. H.; Robciuc, A.; Holma, P.; Holopainen, J. M.; Abdel-Rehim, M.; Wiedmer, S. K.

    2017-01-01

    Roč. 1479, JAN (2017), s. 194-203 ISSN 0021-9673 Institutional support: RVO:68081715 Keywords : liposome electrokinetic chromatography * distribution constants * EOF markers Subject RIV: CB - Analytical Chemistry, Separation OBOR OECD: Analytical chemistry Impact factor: 3.981, year: 2016

  7. Raman imaging to investigate ultrastructure and composition of plant cell walls : distribution of lignin and cellulose in black spruce wood (Picea mariana)

    Science.gov (United States)

    Umesh P. Agarwal

    2006-01-01

    A detailed understanding of the structural organization of the cell wall of vascular plants is important from both the perspectives of plant biology and chemistry and of commercial utilization. A state-of-the-art 633-nm laser-based confocal Raman microscope was used to determine the distribution of cell wall components in the cross section of black spruce wood in situ...

  8. Regional Distribution Shifts Help Explain Local Changes in Wintering Raptor Abundance: Implications for Interpreting Population Trends

    OpenAIRE

    Paprocki, Neil; Heath, Julie A.; Novak, Stephen J.

    2014-01-01

    Studies of multiple taxa across broad-scales suggest that species distributions are shifting poleward in response to global climate change. Recognizing the influence of distribution shifts on population indices will be an important part of interpreting trends within management units because current practice often assumes that changes in local populations reflect local habitat conditions. However, the individual- and population-level processes that drive distribution shifts may occur across a ...

  9. Distributed generation connected to the local network - a guide

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This guide provides advice to the developers and operators of small distributed generation plant (including microgenerators) in the UK about the practical issues associated with connecting their plant and trading their output. Particular attention is given to sales revenues and how to access these revenue streams, including the mechanisms for purchasing Renewable Obligation Certificates (ROCs). The guide clarifies key terms, explains the wholesale trading system and provides an overview of sales opportunities (including ROCs and Levy Exemption Certificates (LECs)). Requirements on small distributed generation (including licensing, claiming class exemptions and metering) are described and the commercial aspects of connection (including the recent reduction in the barriers to connection) examined. Microgeneration (ie generators below 10 kW) issues are covered in their own chapter. The six appendices contain: background information about the industry; a list of purchasers of electricity from small distributed generators; descriptions of the generation, transmission and supply industries; information about industry standards and their governance; the role of government departments and institutions; and a glossary and other links.

  10. An Autonomous Distributed Fault-Tolerant Local Positioning System

    Science.gov (United States)

    Malekpour, Mahyar R.

    2017-01-01

    We describe a fault-tolerant, GPS-independent (Global Positioning System) distributed autonomous positioning system for static/mobile objects and present solutions for providing highly-accurate geo-location data for the static/mobile objects in dynamic environments. The reliability and accuracy of a positioning system fundamentally depends on two factors; its timeliness in broadcasting signals and the knowledge of its geometry, i.e., locations and distances of the beacons. Existing distributed positioning systems either synchronize to a common external source like GPS or establish their own time synchrony using a scheme similar to a master-slave by designating a particular beacon as the master and other beacons synchronize to it, resulting in a single point of failure. Another drawback of existing positioning systems is their lack of addressing various fault manifestations, in particular, communication link failures, which, as in wireless networks, are increasingly dominating the process failures and are typically transient and mobile, in the sense that they typically affect different messages to/from different processes over time.

  11. Possibilities of ultrastructural localization of steroids

    International Nuclear Information System (INIS)

    Magalhaes, M.M.

    1976-01-01

    The application of radioautography to frozen thin sections of the adrenal gland was attempted. The procedure followed was described. In frozen thin sections of unfixed and unembedded material it was possible to identify the nuclei, mitochondria and endoplasmic reticulum spaces. Since the most important metabolic steps of steroidogenesis take place in the latter two compartments, it was deemed worthwhile to attempt radioautography of these sections after cholesterol administration. For this purpose, adrenal slices were incubated in a medium containing 200 μCi of 3 H-cholesterol during 3 minutes

  12. Ultrastructural analysis of the structure and distribution of the adherens junctions in the rats’ ventricular myocardium during postnatal stages of ontogeny after the infl uence of chronic prenatal hypoxia

    Directory of Open Access Journals (Sweden)

    N. S. Petruk

    2013-12-01

    Full Text Available Background. Antenatal and prenatal hypoxia causes changes in all the organs of fetuses and newborns and in the heart, particularly. Hypoxic damage of the cardiovascular system occurs in 40-70% of newborns. Currently we observe the increase of meaning of the morphological studies for the prenatal diagnosis of human’s heart diseases. It’s known that in adaptive remodeling of cardiomyocytes in the postnatal cardiogenesis of rat redistribution of diffusely located intercellular junctions from the periphery to the terminal areas of the cell occurs. The formation of a definitive pattern of intercellular junctions is completed at the puberty. But how chronic prenatal hypoxia influences the specialized adherens junctions in the rats’ ventricular myocardium is completely unknown and this requires further study. Objective. To provide complex qualitative and quantitative comparative ultrastructural analysis of the intercellular connection changes in rat ventricular myocardium on the stages of postnatal ontogenesis in the norm and under the chronic fetal hypoxia. Materials and methods. We have conducted ultrastructural analysis and distribution of the adherens junctions in the rats’ ventricles on the 1st, 3rd, 7th, 14th, 30th days during postnatal ontogeny and among mature animals in the normal development and under the chronic fetal hypoxia. Experimental chronic hypoxia was modeled by intraperitoneal injection of 1% aqueous solution of the NaNO2 in a daily dose of 50 mg/kg of body weight in the term from 10th to 21st days of pregnancy. Transmission electron microscopy, morphometric and statistical methods were applied. Pairwise comparisons between means of different groups were performed using a Student t-test where, for each couple of normally distributed populations, the null hypothesis that the means are equal was verified. Results. Pronounced increase (80,6%; p <0,05 of the content of desmosomes in the intercalated disk in the period from 7th

  13. Supervisor localization a top-down approach to distributed control of discrete-event systems

    CERN Document Server

    Cai, Kai

    2016-01-01

    This monograph presents a systematic top-down approach to distributed control synthesis of discrete-event systems (DES). The approach is called supervisor localization; its essence is the allocation of external supervisory control action to individual component agents as their internal control strategies. The procedure is: first synthesize a monolithic supervisor, to achieve globally optimal and nonblocking controlled behavior, then decompose the monolithic supervisor into local controllers, one for each agent. The collective behavior of the resulting local controllers is identical to that achieved by the monolithic supervisor. The basic localization theory is first presented in the Ramadge–Wonham language-based supervisory control framework, then demonstrated with distributed control examples of multi-robot formations, manufacturing systems, and distributed algorithms. An architectural approach is adopted to apply localization to large-scale DES; this yields a heterarchical localization procedure, which is...

  14. Tools for Local and Distributed Climate Data Access

    Science.gov (United States)

    Schweitzer, R.; O'Brien, K.; Burger, E. F.; Smith, K. M.; Manke, A. B.; Radhakrishnan, A.; Balaji, V.

    2017-12-01

    Last year we reported on our efforts to adapt existing tools to facilitate model development. During the lifecycle of a Climate Model Intercomparison Project (CMIP), data must be quality controlled before it can be published and studied. Like previous efforts, the next CMIP6 will produce an unprecedented volume of data. For an institution, modelling group or modeller the volume of data is unmanageable without tools that organize and automate as many processes as possible. Even if a modelling group has tools for data and metadata management, it often falls on individuals to do the initial quality assessment for a model run with bespoke tools. Using individually crafted tools can lead to interruptions when project personnel change and may result in inconsistencies and duplication of effort across groups. This talk will expand on our experiences using available tools (Ferret/PyFerret, the Live Access Server, the GFDL Curator, the GFDL Model Development Database Interface and the THREDDS Data Server) to seamlessly automate the data assembly process to give users "one-click" access to a rich suite of Web-based analysis and comparison tools. On the surface, it appears that this collection of tools is well suited to the task, but our experience of the last year taught us that the data volume and distributed storage adds a number of challenges in adapting the tools for this task. Quality control and initial evaluation add their own set of challenges. We will discuss how we addressed the needs of QC researchers by expanding standard tools to include specialized plots and leveraged the configurability of the tools to add specific user defined analysis operations so they are available to everyone using the system. We also report on our efforts to overcome some of the technical barriers for wide adoption of the tools by providing pre-built containers that are easily deployed in virtual machine and cloud environments. Finally, we will offer some suggestions for added features

  15. Active local distribution network management for embedded generation

    Energy Technology Data Exchange (ETDEWEB)

    White, S.

    2005-07-01

    With the newer electric power transmission networks, there is a requirement for power to flow in two different directions and this calls for more intelligent forms of management. To satisfy these demands, GENEVAC has produced a controller that aims to increase the energy that power plants can feed to the distribution networks. The software and hardware have undergone trials at two 33/11 kV substations in England. The hardware was designed to monitor voltage, current and phase angle at various points in the network. The software estimates the value of the voltages at every node in the network. The results showed good correlation between estimated and measured voltages: other findings are reported. Recommendations for further work are made including development of a full commercial system. The study was conducted by Econnect Ltd under contract to the DTI.

  16. Energy gradients and the geographic distribution of local ant diversity.

    Science.gov (United States)

    Kaspari, Michael; Ward, Philip S; Yuan, May

    2004-08-01

    Geographical diversity gradients, even among local communities, can ultimately arise from geographical differences in speciation and extinction rates. We evaluated three models--energy-speciation, energy-abundance, and area--that predict how geographic trends in net diversification rates generate trends in diversity. We sampled 96 litter ant communities from four provinces: Australia, Madagascar, North America, and South America. The energy-speciation hypothesis best predicted ant species richness by accurately predicting the slope of the temperature diversity curve, and accounting for most of the variation in diversity. The communities showed a strong latitudinal gradient in species richness as well as inter-province differences in diversity. The former vanished in the temperature-diversity residuals, suggesting that the latitudinal gradient arises primarily from higher diversification rates in the tropics. However, inter-province differences in diversity persisted in those residuals--South American communities remained more diverse than those in North America and Australia even after the effects of temperature were removed.

  17. METALLICITY DISTRIBUTION FUNCTIONS OF FOUR LOCAL GROUP DWARF GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Ross, Teresa L.; Holtzman, Jon [Department of Astronomy, New Mexico State University, P.O. Box 30001, MSC 4500, Las Cruces, NM 88003-8001 (United States); Saha, Abhijit [NOAO, 950 Cherry Avenue, Tucson, AZ 85726-6732 (United States); Anthony-Twarog, Barbara J., E-mail: rosst@nmsu.edu, E-mail: holtz@nmsu.edu, E-mail: bjat@ku.edu [Department of Physics and Astronomy, University of Kansas, Lawrence, KS 66045-7582 (United States)

    2015-06-15

    We present stellar metallicities in Leo I, Leo II, IC 1613, and Phoenix dwarf galaxies derived from medium (F390M) and broad (F555W, F814W) band photometry using the Wide Field Camera 3 instrument on board the Hubble Space Telescope. We measured metallicity distribution functions (MDFs) in two ways, (1) matching stars to isochrones in color–color diagrams and (2) solving for the best linear combination of synthetic populations to match the observed color–color diagram. The synthetic technique reduces the effect of photometric scatter and produces MDFs 30%–50% narrower than the MDFs produced from individually matched stars. We fit the synthetic and individual MDFs to analytical chemical evolution models (CEMs) to quantify the enrichment and the effect of gas flows within the galaxies. Additionally, we measure stellar metallicity gradients in Leo I and II. For IC 1613 and Phoenix our data do not have the radial extent to confirm a metallicity gradient for either galaxy. We find the MDF of Leo I (dwarf spheroidal) to be very peaked with a steep metal-rich cutoff and an extended metal-poor tail, while Leo II (dwarf spheroidal), Phoenix (dwarf transition), and IC 1613 (dwarf irregular) have wider, less peaked MDFs than Leo I. A simple CEM is not the best fit for any of our galaxies; therefore we also fit the “Best Accretion Model” of Lynden-Bell. For Leo II, IC 1613, and Phoenix we find similar accretion parameters for the CEM even though they all have different effective yields, masses, star formation histories, and morphologies. We suggest that the dynamical history of a galaxy is reflected in the MDF, where broad MDFs are seen in galaxies that have chemically evolved in relative isolation and narrowly peaked MDFs are seen in galaxies that have experienced more complicated dynamical interactions concurrent with their chemical evolution.

  18. A Local Scalable Distributed EM Algorithm for Large P2P Networks

    Data.gov (United States)

    National Aeronautics and Space Administration — his paper describes a local and distributed expectation maximization algorithm for learning parameters of Gaussian mixture models (GMM) in large peer-to-peer (P2P)...

  19. A Local Scalable Distributed Expectation Maximization Algorithm for Large Peer-to-Peer Networks

    Data.gov (United States)

    National Aeronautics and Space Administration — This paper describes a local and distributed expectation maximization algorithm for learning parameters of Gaussian mixture models (GMM) in large peer-to-peer (P2P)...

  20. A Local Asynchronous Distributed Privacy Preserving Feature Selection Algorithm for Large Peer-to-Peer Networks

    Data.gov (United States)

    National Aeronautics and Space Administration — In this paper we develop a local distributed privacy preserving algorithm for feature selection in a large peer-to-peer environment. Feature selection is often used...

  1. Study of the localization of slaughterhouses and distribution center of broilers agroindustries in Distrito Federal

    Directory of Open Access Journals (Sweden)

    Eliane Almeida do Carmo

    2011-02-01

    Full Text Available The work investigated the localization of an avian industry and optimized its net, from the corporatives to the consumers, determining the amount of slaughterhouses and distribution centers that the concern should possess and their localization in order to minimize costs. From the collection of real data and by utilizing tools of Geographic Information Systems and binary linear programming, the optimum setting for the net as well the setting of several alternative scenarios were determined. The objective function utilized minimizes the sum of the costs of the slaughterhouse localization, the costs of the localization of the distribution center, the production costs and shipment of the living chickens from the corporatives to the slaughterhouse, the costs of slaughter and shipment as far as the distribution center and the storage costs in the distribution center and shipment to the end clients. The optimum scenario obtained takes into account only the establishment of a slaughterhouse and a distribution center of increased capacity, standing out scale gains. The results support the localization of slaughterhouses close to the coporatives and distribution centers close to the clients submitted to the several restrictions imposed by the local reality.

  2. COM-LOC: A Distributed Range-Free Localization Algorithm in Wireless Networks

    NARCIS (Netherlands)

    Dil, B.J.; Havinga, Paul J.M.; Marusic, S; Palaniswami, M; Gubbi, J.; Law, Y.W.

    2009-01-01

    This paper investigates distributed range-free localization in wireless networks using a communication protocol called sum-dist which is commonly employed by localization algorithms. With this protocol, the reference nodes flood the network in order to estimate the shortest distance between the

  3. Local, distributed topology control for large-scale wireless ad-hoc networks

    NARCIS (Netherlands)

    Nieberg, T.; Hurink, Johann L.

    In this document, topology control of a large-scale, wireless network by a distributed algorithm that uses only locally available information is presented. Topology control algorithms adjust the transmission power of wireless nodes to create a desired topology. The algorithm, named local power

  4. Regional Distribution Shifts Help Explain Local Changes in Wintering Raptor Abundance: Implications for Interpreting Population Trends

    Science.gov (United States)

    Paprocki, Neil; Heath, Julie A.; Novak, Stephen J.

    2014-01-01

    Studies of multiple taxa across broad-scales suggest that species distributions are shifting poleward in response to global climate change. Recognizing the influence of distribution shifts on population indices will be an important part of interpreting trends within management units because current practice often assumes that changes in local populations reflect local habitat conditions. However, the individual- and population-level processes that drive distribution shifts may occur across a large, regional scale and have little to do with the habitats within the management unit. We examined the latitudinal center of abundance for the winter distributions of six western North America raptor species using Christmas Bird Counts from 1975–2011. Also, we considered whether population indices within western North America Bird Conservation Regions (BCRs) were explained by distribution shifts. All six raptors had significant poleward shifts in their wintering distributions over time. Rough-legged Hawks (Buteo lagopus) and Golden Eagles (Aquila chrysaetos) showed the fastest rate of change, with 8.41 km yr−1 and 7.74 km yr−1 shifts, respectively. Raptors may be particularly responsive to warming winters because of variable migration tendencies, intraspecific competition for nesting sites that drives males to winter farther north, or both. Overall, 40% of BCR population trend models were improved by incorporating information about wintering distributions; however, support for the effect of distribution on BCR indices varied by species with Rough-legged Hawks showing the most evidence. These results emphasize the importance of understanding how regional distribution shifts influence local-scale population indices. If global climate change is altering distribution patterns, then trends within some management units may not reflect changes in local habitat conditions. The methods used to monitor and manage bird populations within local BCRs will fundamentally change as

  5. Regional distribution shifts help explain local changes in wintering raptor abundance: implications for interpreting population trends.

    Directory of Open Access Journals (Sweden)

    Neil Paprocki

    Full Text Available Studies of multiple taxa across broad-scales suggest that species distributions are shifting poleward in response to global climate change. Recognizing the influence of distribution shifts on population indices will be an important part of interpreting trends within management units because current practice often assumes that changes in local populations reflect local habitat conditions. However, the individual- and population-level processes that drive distribution shifts may occur across a large, regional scale and have little to do with the habitats within the management unit. We examined the latitudinal center of abundance for the winter distributions of six western North America raptor species using Christmas Bird Counts from 1975-2011. Also, we considered whether population indices within western North America Bird Conservation Regions (BCRs were explained by distribution shifts. All six raptors had significant poleward shifts in their wintering distributions over time. Rough-legged Hawks (Buteo lagopus and Golden Eagles (Aquila chrysaetos showed the fastest rate of change, with 8.41 km yr(-1 and 7.74 km yr(-1 shifts, respectively. Raptors may be particularly responsive to warming winters because of variable migration tendencies, intraspecific competition for nesting sites that drives males to winter farther north, or both. Overall, 40% of BCR population trend models were improved by incorporating information about wintering distributions; however, support for the effect of distribution on BCR indices varied by species with Rough-legged Hawks showing the most evidence. These results emphasize the importance of understanding how regional distribution shifts influence local-scale population indices. If global climate change is altering distribution patterns, then trends within some management units may not reflect changes in local habitat conditions. The methods used to monitor and manage bird populations within local BCRs will fundamentally

  6. Myocardial distribution of I131-labeled hexadecenoic acid in relation to the dog local coronary flow

    International Nuclear Information System (INIS)

    Riche, F.; Busquet, G.; Pilichowski, P.; Wolf, J.E.; Mathieu, J.P.; Comet, M.; Pernin, C.; Vidal, M.; Vincens, M.; Godart, J.

    1981-01-01

    20 anesthetized and thoracotomized dogs are studied. The local myocardial blood flow is measured with sup(99m)Tc human albumin microspheres. The intramyocardial distribution of the 16-I(131)-9-hexadecenoic acid in relation to local blood flow is studied in basal conditions (7 dogs), after experimental infarction (6 dogs) and postischemic reactive hyperhemia (7 dogs). We conclude that during basal condition, after infarction but not during reactive hyperhemia, the distribution of the labeled fatty acid reflect the local variations of blood flow [fr

  7. Novel active contour model based on multi-variate local Gaussian distribution for local segmentation of MR brain images

    Science.gov (United States)

    Zheng, Qiang; Li, Honglun; Fan, Baode; Wu, Shuanhu; Xu, Jindong

    2017-12-01

    Active contour model (ACM) has been one of the most widely utilized methods in magnetic resonance (MR) brain image segmentation because of its ability of capturing topology changes. However, most of the existing ACMs only consider single-slice information in MR brain image data, i.e., the information used in ACMs based segmentation method is extracted only from one slice of MR brain image, which cannot take full advantage of the adjacent slice images' information, and cannot satisfy the local segmentation of MR brain images. In this paper, a novel ACM is proposed to solve the problem discussed above, which is based on multi-variate local Gaussian distribution and combines the adjacent slice images' information in MR brain image data to satisfy segmentation. The segmentation is finally achieved through maximizing the likelihood estimation. Experiments demonstrate the advantages of the proposed ACM over the single-slice ACM in local segmentation of MR brain image series.

  8. Development of neural network for analysis of local power distributions in BWR fuel bundles

    International Nuclear Information System (INIS)

    Tanabe, Akira; Yamamoto, Toru; Shinfuku, Kimihiro; Nakamae, Takuji.

    1993-01-01

    A neural network model has been developed to learn the local power distributions in a BWR fuel bundle. A two layers neural network with total 128 elements is used for this model. The neural network learns 33 cases of local power peaking factors of fuel rods with given enrichment distribution as the teacher signals, which were calculated by a fuel bundle nuclear analysis code based on precise physical models. This neural network model studied well the teacher signals within 1 % error. It is also able to calculate the local power distributions within several % error for the different enrichment distributions from the teacher signals when the average enrichment is close to 2 %. This neural network is simple and the computing speed of this model is 300 times faster than that of the precise nuclear analysis code. This model was applied to survey the enrichment distribution to meet a target local power distribution in a fuel bundle, and the enrichment distribution with flat power shape are obtained within short computing time. (author)

  9. Local Flexibility Market Design for Aggregators Providing Multiple Flexibility Services at Distribution Network Level

    Directory of Open Access Journals (Sweden)

    Pol Olivella-Rosell

    2018-04-01

    Full Text Available This paper presents a general description of local flexibility markets as a market-based management mechanism for aggregators. The high penetration of distributed energy resources introduces new flexibility services like prosumer or community self-balancing, congestion management and time-of-use optimization. This work is focused on the flexibility framework to enable multiple participants to compete for selling or buying flexibility. In this framework, the aggregator acts as a local market operator and supervises flexibility transactions of the local energy community. Local market participation is voluntary. Potential flexibility stakeholders are the distribution system operator, the balance responsible party and end-users themselves. Flexibility is sold by means of loads, generators, storage units and electric vehicles. Finally, this paper presents needed interactions between all local market stakeholders, the corresponding inputs and outputs of local market operation algorithms from participants and a case study to highlight the application of the local flexibility market in three scenarios. The local market framework could postpone grid upgrades, reduce energy costs and increase distribution grids’ hosting capacity.

  10. Inference for Local Distributions at High Sampling Frequencies: A Bootstrap Approach

    DEFF Research Database (Denmark)

    Hounyo, Ulrich; Varneskov, Rasmus T.

    of "large" jumps. Our locally dependent wild bootstrap (LDWB) accommodate issues related to the stochastic scale and jumps as well as account for a special block-wise dependence structure induced by sampling errors. We show that the LDWB replicates first and second-order limit theory from the usual...... empirical process and the stochastic scale estimate, respectively, as well as an asymptotic bias. Moreover, we design the LDWB sufficiently general to establish asymptotic equivalence between it and and a nonparametric local block bootstrap, also introduced here, up to second-order distribution theory....... Finally, we introduce LDWB-aided Kolmogorov-Smirnov tests for local Gaussianity as well as local von-Mises statistics, with and without bootstrap inference, and establish their asymptotic validity using the second-order distribution theory. The finite sample performance of CLT and LDWB-aided local...

  11. A hand-held sensor for analyses of local distributions of magnetic fields and losses

    CERN Document Server

    Krismanic, G; Baumgartinger, N

    2000-01-01

    The paper describes a novel sensor for non-destructive analyses of local field and loss distributions in laminated soft magnetic cores, such as transformer cores. It was designed for rapid information on comparative local degrees of inhomogeneity, e.g., for the estimation of local building factors. Similar to a magnifying glass with handle, the compact hand-held sensor contains extremely sharp needle electrodes for the detection of the induction vector B as well as double-field coils for the vector H. Losses P are derived from the Poynting law. Applied to inner -- or also outer -- core regions, the sensor yields instantaneous computer displays of local H, B, and P.

  12. Composition and distribution of cell wall phenolic compounds in flax (Linum usitatissimum L.) stem tissues

    NARCIS (Netherlands)

    Gorshkova, T.A.; Salnikov, V.V.; Pogodina, N.M.; Chemikosova, S.B.; Yablokova, E.V.; Ulanov, A.V.; Ageeva, M.V.; Dam, van J.E.G.; Lozovaya, V.V.

    2000-01-01

    Cell wall phenolic compounds were analysed in xylem and bast fibre-rich peels of flax stems by biochemical, histochemical and ultrastructural approaches. Localization of cell wall phenolics by the enzyme-gold method using laccase revealed several gold particle distribution patterns. One of the major

  13. Distributed Power Allocation for Wireless Sensor Network Localization: A Potential Game Approach.

    Science.gov (United States)

    Ke, Mingxing; Li, Ding; Tian, Shiwei; Zhang, Yuli; Tong, Kaixiang; Xu, Yuhua

    2018-05-08

    The problem of distributed power allocation in wireless sensor network (WSN) localization systems is investigated in this paper, using the game theoretic approach. Existing research focuses on the minimization of the localization errors of individual agent nodes over all anchor nodes subject to power budgets. When the service area and the distribution of target nodes are considered, finding the optimal trade-off between localization accuracy and power consumption is a new critical task. To cope with this issue, we propose a power allocation game where each anchor node minimizes the square position error bound (SPEB) of the service area penalized by its individual power. Meanwhile, it is proven that the power allocation game is an exact potential game which has one pure Nash equilibrium (NE) at least. In addition, we also prove the existence of an ϵ -equilibrium point, which is a refinement of NE and the better response dynamic approach can reach the end solution. Analytical and simulation results demonstrate that: (i) when prior distribution information is available, the proposed strategies have better localization accuracy than the uniform strategies; (ii) when prior distribution information is unknown, the performance of the proposed strategies outperforms power management strategies based on the second-order cone program (SOCP) for particular agent nodes after obtaining the estimated distribution of agent nodes. In addition, proposed strategies also provide an instructional trade-off between power consumption and localization accuracy.

  14. Surface micro-distributions of pigment and the relation between smearing and local mass distribution

    International Nuclear Information System (INIS)

    Buelow, K.; Kristiansson, P.; Larsson, T.; Malmberg, S.; Elfman, M.; Malmqvist, K.; Pallon, J.; Shariff, A.

    2001-01-01

    In this work, the process of smearing and its time evolution have been investigated. When smearing occurs, the print is removed from the printed paper and colours other parts of the paper or the printing press and destroys the final product. To study the re-distribution of ink, cyan ink with Cu as a tracer in the coloured pigment has been used. Non-printed paper has been pressed against the paper, 1 and 5 s after the printing. The micro-distributions of ink on both printed and non-printed papers have then been studied using particle-induced X-ray emission (PIXE). Basis weight was measured with the off-axis scanning transmission ion microscopy (STIM) technique and this data was correlated with the data from the print. One conclusion is that the process of smearing is not dependent on the shape of the pigment distribution, i.e. copper, or the content of copper in a specific pixel. On the contrary, the smearing was found to be related to the structure of the paper and that it mainly occurs where the paper is thicker

  15. Ultrastructure of the human preovulatory oocyte.

    Science.gov (United States)

    Szöllösi, D; Mandelbaum, J; Plachot, M; Salat-Baroux, J; Cohen, J

    1986-08-01

    The ultrastructure of preovulatory human oocyte-cumulus complexes was described after inducing maturation by clomiphene, human menopausal gonadotropin (hMG), human chorionic gonadotropin (hCG) treatment. The majority of the oocytes was at metaphase II of meiosis, with a radially orientated spindle. The oocyte surface was covered by a multitude of microvilli. Cortical granules were nonuniformly distributed along the cortex. A cytoplasmic polarization was observed. The cytoplasmic organelles were in general uniformly dispersed, with the exception of a narrow segment within which cytoplasmic membranes and mitochondria formed clusters. The spindle was usually found at the borderline between the two regions of the cytoplasm. The functional significance of this polarization is not yet known.

  16. Optimal distribution of temperature points in μSR measurement of local field

    International Nuclear Information System (INIS)

    Pełka, R.; Zieliński, P.M.; Konieczny, P.; Wasiutyński, T.

    2013-01-01

    Three possible distributions of temperature points in the μSR measurement of local field (order parameter) are discussed. The least square method is applied to estimate the scale of the deviations of the fitted parameters from the true values. It indicates that the distribution corresponding to a uniform section of the order parameter values (uniform-in-signal) incurs the smallest errors. The distribution constructed on the basis of the zeros of the Chebyshev polynomials yields comparable uncertainties, while the uniform-in-temperature distribution turns out to be least effective incurring considerably larger errors. These findings can be useful while planning an order parameter measurement in the μSR experiment

  17. Combined local current distribution measurements and high resolution neutron radiography of operating direct methanol fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, Alexander; Wippermann, Klaus [Forschungszentrum Juelich GmbH (Germany). Inst. of Energy Research, IEF-3: Fuel Cells; Sanders, Tilman [RWTH Aachen (DE). Inst. for Power Electronics and Electrical Drives (ISEA); Arlt, Tobias [Helmholtz Centre Berlin (Germany). Inst. for Applied Materials

    2010-07-01

    Neutron radiography allows the investigation of the local fluid distribution in direct methanol fuel cells (DMFCs) under operating conditions. Spatial resolutions in the order of some tens of micrometers at the full test cell area are achieved. This offers the possibility to study practice-oriented, large stack cells with an active area of several hundred cm{sup 2} as well as specially designed, small test cells with an area of some cm{sup 2}. Combined studies of high resolution neutron radiography and segmented cell measurements are especially valuable, because they enable a correlation of local fluid distribution and local performance [1, 2]. The knowledge of this interdependency is essential to optimise the water management and performance respecting a homogeneous fluid, current and temperature distribution and to achieve high performance and durability of DMFCs. (orig.)

  18. A density distribution algorithm for bone incorporating local orthotropy, modal analysis and theories of cellular solids.

    Science.gov (United States)

    Impelluso, Thomas J

    2003-06-01

    An algorithm for bone remodeling is presented which allows for both a redistribution of density and a continuous change of principal material directions for the orthotropic material properties of bone. It employs a modal analysis to add density for growth and a local effective strain based analysis to redistribute density. General re-distribution functions are presented. The model utilizes theories of cellular solids to relate density and strength. The code predicts the same general density distributions and local orthotropy as observed in reality.

  19. Procedure of non-contacting local mass density and mass density distribution measurements

    International Nuclear Information System (INIS)

    Menzel, M.; Winkler, K.

    1985-01-01

    The invention has been aimed at a procedure of non-contacting local mass density and/or mass density distribution measurements i.e. without the interfering influence of sensors or probes. It can be applied to installations, apparatuses and pipings of chemical engineering, to tank constructions and transportation on extreme temperature and/or pressure conditions and aggressive media influences respectively. The procedure has utilized an ionizing quantum radiation whereby its unknown weakening and scattering is compensated by a suitable combination of scattering and transmission counter rate measurements in such a way that the local mass densities and the mass density distribution respectively are determinable

  20. Local and global stability for Lotka-Volterra systems with distributed delays and instantaneous negative feedbacks

    Science.gov (United States)

    Faria, Teresa; Oliveira, José J.

    This paper addresses the local and global stability of n-dimensional Lotka-Volterra systems with distributed delays and instantaneous negative feedbacks. Necessary and sufficient conditions for local stability independent of the choice of the delay functions are given, by imposing a weak nondelayed diagonal dominance which cancels the delayed competition effect. The global asymptotic stability of positive equilibria is established under conditions slightly stronger than the ones required for the linear stability. For the case of monotone interactions, however, sharper conditions are presented. This paper generalizes known results for discrete delays to systems with distributed delays. Several applications illustrate the results.

  1. Multiobjective Memetic Estimation of Distribution Algorithm Based on an Incremental Tournament Local Searcher

    Directory of Open Access Journals (Sweden)

    Kaifeng Yang

    2014-01-01

    Full Text Available A novel hybrid multiobjective algorithm is presented in this paper, which combines a new multiobjective estimation of distribution algorithm, an efficient local searcher and ε-dominance. Besides, two multiobjective problems with variable linkages strictly based on manifold distribution are proposed. The Pareto set to the continuous multiobjective optimization problems, in the decision space, is a piecewise low-dimensional continuous manifold. The regularity by the manifold features just build probability distribution model by globally statistical information from the population, yet, the efficiency of promising individuals is not well exploited, which is not beneficial to search and optimization process. Hereby, an incremental tournament local searcher is designed to exploit local information efficiently and accelerate convergence to the true Pareto-optimal front. Besides, since ε-dominance is a strategy that can make multiobjective algorithm gain well distributed solutions and has low computational complexity, ε-dominance and the incremental tournament local searcher are combined here. The novel memetic multiobjective estimation of distribution algorithm, MMEDA, was proposed accordingly. The algorithm is validated by experiment on twenty-two test problems with and without variable linkages of diverse complexities. Compared with three state-of-the-art multiobjective optimization algorithms, our algorithm achieves comparable results in terms of convergence and diversity metrics.

  2. Multiobjective memetic estimation of distribution algorithm based on an incremental tournament local searcher.

    Science.gov (United States)

    Yang, Kaifeng; Mu, Li; Yang, Dongdong; Zou, Feng; Wang, Lei; Jiang, Qiaoyong

    2014-01-01

    A novel hybrid multiobjective algorithm is presented in this paper, which combines a new multiobjective estimation of distribution algorithm, an efficient local searcher and ε-dominance. Besides, two multiobjective problems with variable linkages strictly based on manifold distribution are proposed. The Pareto set to the continuous multiobjective optimization problems, in the decision space, is a piecewise low-dimensional continuous manifold. The regularity by the manifold features just build probability distribution model by globally statistical information from the population, yet, the efficiency of promising individuals is not well exploited, which is not beneficial to search and optimization process. Hereby, an incremental tournament local searcher is designed to exploit local information efficiently and accelerate convergence to the true Pareto-optimal front. Besides, since ε-dominance is a strategy that can make multiobjective algorithm gain well distributed solutions and has low computational complexity, ε-dominance and the incremental tournament local searcher are combined here. The novel memetic multiobjective estimation of distribution algorithm, MMEDA, was proposed accordingly. The algorithm is validated by experiment on twenty-two test problems with and without variable linkages of diverse complexities. Compared with three state-of-the-art multiobjective optimization algorithms, our algorithm achieves comparable results in terms of convergence and diversity metrics.

  3. Fire Source Localization Based on Distributed Temperature Sensing by a Dual-Line Optical Fiber System.

    Science.gov (United States)

    Sun, Miao; Tang, Yuquan; Yang, Shuang; Li, Jun; Sigrist, Markus W; Dong, Fengzhong

    2016-06-06

    We propose a method for localizing a fire source using an optical fiber distributed temperature sensor system. A section of two parallel optical fibers employed as the sensing element is installed near the ceiling of a closed room in which the fire source is located. By measuring the temperature of hot air flows, the problem of three-dimensional fire source localization is transformed to two dimensions. The method of the source location is verified with experiments using burning alcohol as fire source, and it is demonstrated that the method represents a robust and reliable technique for localizing a fire source also for long sensing ranges.

  4. SPATIAL DISTRIBUTIONS OF ABSORPTION, LOCAL SUPPRESSION, AND EMISSIVITY REDUCTION OF SOLAR ACOUSTIC WAVES IN MAGNETIC REGIONS

    International Nuclear Information System (INIS)

    Chou, D.-Y.; Yang, M.-H.; Zhao Hui; Liang Zhichao; Sun, M.-T.

    2009-01-01

    Observed acoustic power in magnetic regions is lower than the quiet Sun because of absorption, emissivity reduction, and local suppression of solar acoustic waves in magnetic regions. In the previous studies, we have developed a method to measure the coefficients of absorption, emissivity reduction, and local suppression of sunspots. In this study, we go one step further to measure the spatial distributions of three coefficients in two active regions, NOAA 9055 and 9057. The maps of absorption, emissivity reduction, and local suppression coefficients correlate with the magnetic map, including plage regions, except the emissivity reduction coefficient of NOAA 9055 where the emissivity reduction coefficient is too weak and lost among the noise.

  5. Fire Source Localization Based on Distributed Temperature Sensing by a Dual-Line Optical Fiber System

    Directory of Open Access Journals (Sweden)

    Miao Sun

    2016-06-01

    Full Text Available We propose a method for localizing a fire source using an optical fiber distributed temperature sensor system. A section of two parallel optical fibers employed as the sensing element is installed near the ceiling of a closed room in which the fire source is located. By measuring the temperature of hot air flows, the problem of three-dimensional fire source localization is transformed to two dimensions. The method of the source location is verified with experiments using burning alcohol as fire source, and it is demonstrated that the method represents a robust and reliable technique for localizing a fire source also for long sensing ranges.

  6. Local host specialization, host-switching, and dispersal shape the regional distributions of avian haemosporidian parasites.

    Science.gov (United States)

    Ellis, Vincenzo A; Collins, Michael D; Medeiros, Matthew C I; Sari, Eloisa H R; Coffey, Elyse D; Dickerson, Rebecca C; Lugarini, Camile; Stratford, Jeffrey A; Henry, Donata R; Merrill, Loren; Matthews, Alix E; Hanson, Alison A; Roberts, Jackson R; Joyce, Michael; Kunkel, Melanie R; Ricklefs, Robert E

    2015-09-08

    The drivers of regional parasite distributions are poorly understood, especially in comparison with those of free-living species. For vector-transmitted parasites, in particular, distributions might be influenced by host-switching and by parasite dispersal with primary hosts and vectors. We surveyed haemosporidian blood parasites (Plasmodium and Haemoproteus) of small land birds in eastern North America to characterize a regional parasite community. Distributions of parasite populations generally reflected distributions of their hosts across the region. However, when the interdependence between hosts and parasites was controlled statistically, local host assemblages were related to regional climatic gradients, but parasite assemblages were not. Moreover, because parasite assemblage similarity does not decrease with distance when controlling for host assemblages and climate, parasites evidently disperse readily within the distributions of their hosts. The degree of specialization on hosts varied in some parasite lineages over short periods and small geographic distances independently of the diversity of available hosts and potentially competing parasite lineages. Nonrandom spatial turnover was apparent in parasite lineages infecting one host species that was well-sampled within a single year across its range, plausibly reflecting localized adaptations of hosts and parasites. Overall, populations of avian hosts generally determine the geographic distributions of haemosporidian parasites. However, parasites are not dispersal-limited within their host distributions, and they may switch hosts readily.

  7. Distributed push-pull estimation for node localization in wireless sensor networks

    NARCIS (Netherlands)

    Dang, Viet-Hung; Le Viet Duc, L Duc; Lee, Young-Koo; Lee, Sungyoung

    A great deal of research achievements on localization in wireless sensor networks (WSNs) has been obtained in recent years. Nevertheless, its interesting challenges in terms of cost-reduction, accuracy improvement, scalability, and distributed ability design have led to the development of a new

  8. Carriers' localization and thermal redistribution in post growth voluntarily tuned quantum dashes' size/composition distribution

    International Nuclear Information System (INIS)

    Alouane, M.H. Hadj; Helali, A.; Morris, D.; Maaref, H.; Aimez, V.; Salem, B.; Gendry, M.

    2014-01-01

    This paper treats the impact of post growth tuned InAs/InP quantum dashes' (QDas) size/composition distribution on carriers' localization and thermal redistribution. The spread of this distribution depends on the experimental conditions used for the phosphorus ion implantation enhanced intermixing process. Atypical temperature-dependent luminescence properties have been observed and found to be strongly dependent on the amount of QDas size/composition dispersion. The experimental results have been reproduced by a model that takes into account the width of the QDas localized states distribution and consequent thermally induced carriers' redistribution. This model gives critical temperature values marking the beginning and the end of carriers delocalization and thermal transfer processes via an intermixing induced carrier's transfer channel located below the wetting layer states. -- Highlights: • We examine optical properties of post growth tuned QDas size/composition distribution. • Carriers' localization and thermal redistribution within inhomogeneously intermixed QDas are the origin of the atypical temperature-dependent luminescence properties. • Localized states ensemble's model is successively used to interpret the experimental results. • The carriers thermal transfer processes occur via an intermixing induced channel located below the wetting layer states. • Intermixing degree strongly influence the critical temperatures marking the beginning and the end of the carriers thermal transfer processes

  9. Predictive Distribution of the Dirichlet Mixture Model by the Local Variational Inference Method

    DEFF Research Database (Denmark)

    Ma, Zhanyu; Leijon, Arne; Tan, Zheng-Hua

    2014-01-01

    the predictive likelihood of the new upcoming data, especially when the amount of training data is small. The Bayesian estimation of a Dirichlet mixture model (DMM) is, in general, not analytically tractable. In our previous work, we have proposed a global variational inference-based method for approximately...... calculating the posterior distributions of the parameters in the DMM analytically. In this paper, we extend our previous study for the DMM and propose an algorithm to calculate the predictive distribution of the DMM with the local variational inference (LVI) method. The true predictive distribution of the DMM...... is analytically intractable. By considering the concave property of the multivariate inverse beta function, we introduce an upper-bound to the true predictive distribution. As the global minimum of this upper-bound exists, the problem is reduced to seek an approximation to the true predictive distribution...

  10. Ultrastructural researches on rabbit myxomatosis. Lymphnodal lesions.

    Science.gov (United States)

    Marcato, P S; Simoni, P

    1977-07-01

    Ultrastructural examination of head and neck lymph nodes in rabbits with spontaneous subacute myxomatosis showed fusion of immature reticuloendothelial cells which lead to the formation of polykarocytes. There was no ultrastructural evidence of viral infection of these polykaryocytes. Histiosyncytial lymphadenitis can be considered a specific lesion of myxomatosis.

  11. Feature Extraction Method for High Impedance Ground Fault Localization in Radial Power Distribution Networks

    DEFF Research Database (Denmark)

    Jensen, Kåre Jean; Munk, Steen M.; Sørensen, John Aasted

    1998-01-01

    A new approach to the localization of high impedance ground faults in compensated radial power distribution networks is presented. The total size of such networks is often very large and a major part of the monitoring of these is carried out manually. The increasing complexity of industrial...... of three phase voltages and currents. The method consists of a feature extractor, based on a grid description of the feeder by impulse responses, and a neural network for ground fault localization. The emphasis of this paper is the feature extractor, and the detection of the time instance of a ground fault...... processes and communication systems lead to demands for improved monitoring of power distribution networks so that the quality of power delivery can be kept at a controlled level. The ground fault localization method for each feeder in a network is based on the centralized frequency broadband measurement...

  12. Distributed model predictive control for constrained nonlinear systems with decoupled local dynamics.

    Science.gov (United States)

    Zhao, Meng; Ding, Baocang

    2015-03-01

    This paper considers the distributed model predictive control (MPC) of nonlinear large-scale systems with dynamically decoupled subsystems. According to the coupled state in the overall cost function of centralized MPC, the neighbors are confirmed and fixed for each subsystem, and the overall objective function is disassembled into each local optimization. In order to guarantee the closed-loop stability of distributed MPC algorithm, the overall compatibility constraint for centralized MPC algorithm is decomposed into each local controller. The communication between each subsystem and its neighbors is relatively low, only the current states before optimization and the optimized input variables after optimization are being transferred. For each local controller, the quasi-infinite horizon MPC algorithm is adopted, and the global closed-loop system is proven to be exponentially stable. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  13. Optimization of distribution piping network in district cooling system using genetic algorithm with local search

    International Nuclear Information System (INIS)

    Chan, Apple L.S.; Hanby, Vic I.; Chow, T.T.

    2007-01-01

    A district cooling system is a sustainable means of distribution of cooling energy through mass production. A cooling medium like chilled water is generated at a central refrigeration plant and supplied to serve a group of consumer buildings through a piping network. Because of the substantial capital investment involved, an optimal design of the distribution piping configuration is one of the crucial factors for successful implementation of the district cooling scheme. In the present study, genetic algorithm (GA) incorporated with local search techniques was developed to find the optimal/near optimal configuration of the piping network in a hypothetical site. The effect of local search, mutation rate and frequency of local search on the performance of the GA in terms of both solution quality and computation time were investigated and presented in this paper

  14. Scalable and Fully Distributed Localization in Large-Scale Sensor Networks

    Directory of Open Access Journals (Sweden)

    Miao Jin

    2017-06-01

    Full Text Available This work proposes a novel connectivity-based localization algorithm, well suitable for large-scale sensor networks with complex shapes and a non-uniform nodal distribution. In contrast to current state-of-the-art connectivity-based localization methods, the proposed algorithm is highly scalable with linear computation and communication costs with respect to the size of the network; and fully distributed where each node only needs the information of its neighbors without cumbersome partitioning and merging process. The algorithm is theoretically guaranteed and numerically stable. Moreover, the algorithm can be readily extended to the localization of networks with a one-hop transmission range distance measurement, and the propagation of the measurement error at one sensor node is limited within a small area of the network around the node. Extensive simulations and comparison with other methods under various representative network settings are carried out, showing the superior performance of the proposed algorithm.

  15. Distribution of local magnetic field of vortex lattice near anisotropic superconductor surface in inclined external fields

    International Nuclear Information System (INIS)

    Efremova, S.A.; Tsarevskij, S.L.

    1997-01-01

    Magnetic field distribution in a unit cell of the Abrikosov vortex lattice near the surface of monoaxial anisotropic type-ii superconductors in inclined external magnetic field has been found in the framework of London model for the cases when the symmetry axis is perpendicular and parallel to the superconductor surface interface. Distribution of local magnetic field as a function of the distance from the superconductor interface surface and external field inclination angle has been obtained. Using high-Tc superconductor Y-Ba-Cu-O by way of examples, it has been shown that the study of local magnetic field distribution function, depending on external magnetic field inclination angle towards the superconductor symmetry axis and towards the superconductor surface, can provide important data on anisotropic properties of the superconductor [ru

  16. Local and Widely Distributed EEG Activity in Schizophrenia With Prevalence of Negative Symptoms.

    Science.gov (United States)

    Grin-Yatsenko, Vera A; Ponomarev, Valery A; Pronina, Marina V; Poliakov, Yury I; Plotnikova, Irina V; Kropotov, Juri D

    2017-09-01

    We evaluated EEG frequency abnormalities in resting state (eyes closed and eyes open) EEG in a group of chronic schizophrenia patients as compared with healthy subjects. The study included 3 methods of analysis of deviation of EEG characteristics: genuine EEG, current source density (CSD), and group independent component (gIC). All 3 methods have shown that the EEG in schizophrenia patients is characterized by enhanced low-frequency (delta and theta) and high-frequency (beta) activity in comparison with the control group. However, the spatial pattern of differences was dependent on the type of method used. Comparative analysis has shown that increased EEG power in schizophrenia patients apparently concerns both widely spatially distributed components and local components of signal. Furthermore, the observed differences in the delta and theta range can be described mainly by the local components, and those in the beta range mostly by spatially widely distributed ones. The possible nature of the widely distributed activity is discussed.

  17. Detection prospects for high energy neutrino sources from the anisotropic matter distribution in the local universe

    DEFF Research Database (Denmark)

    Mertsch, Philipp; Rameez, Mohamed; Tamborra, Irene

    2017-01-01

    Constraints on the number and luminosity of the sources of the cosmic neutrinos detected by IceCube have been set by targeted searches for point sources. We set complementary constraints by using the 2MASS Redshift Survey (2MRS) catalogue, which maps the matter distribution of the local Universe....... Assuming that the distribution of the neutrino sources follows that of matter we look for correlations between `warm' spots on the IceCube skymap and the 2MRS matter distribution. Through Monte Carlo simulations of the expected number of neutrino multiplets and careful modelling of the detector performance...... (including that of IceCube-Gen2) we demonstrate that sources with local density exceeding $10^{-6} \\, \\text{Mpc}^{-3}$ and neutrino luminosity $L_{\

  18. Nanoscale Correlated Disorder in Out-of-Equilibrium Myelin Ultrastructure.

    Science.gov (United States)

    Campi, Gaetano; Di Gioacchino, Michael; Poccia, Nicola; Ricci, Alessandro; Burghammer, Manfred; Ciasca, Gabriele; Bianconi, Antonio

    2018-01-23

    Ultrastructural fluctuations at nanoscale are fundamental to assess properties and functionalities of advanced out-of-equilibrium materials. We have taken myelin as a model of supramolecular assembly in out-of-equilibrium living matter. Myelin sheath is a simple stable multilamellar structure of high relevance and impact in biomedicine. Although it is known that myelin has a quasi-crystalline ultrastructure, there is no information on its fluctuations at nanoscale in different states due to limitations of the available standard techniques. To overcome these limitations, we have used scanning micro X-ray diffraction, which is a unique non-invasive probe of both reciprocal and real space to visualize statistical fluctuations of myelin order of the sciatic nerve of Xenopus laevis. The results show that the ultrastructure period of the myelin is stabilized by large anticorrelated fluctuations at nanoscale, between hydrophobic and hydrophilic layers. The ratio between the total thickness of hydrophilic and hydrophobic layers defines the conformational parameter, which describes the different states of myelin. Our key result is that myelin in its out-of-equilibrium functional state fluctuates point-to-point between different conformations showing a correlated disorder described by a Levy distribution. As the system approaches the thermodynamic equilibrium in an aged state, the disorder loses its correlation degree and the structural fluctuation distribution changes to Gaussian. In a denatured state at low pH, it changes to a completely disordered stage. Our results aim to clarify the degradation mechanism in biological systems by associating these states with ultrastructural dynamic fluctuations at nanoscale.

  19. We are not the 99 percent: quantifying asphericity in the distribution of Local Group satellites

    Science.gov (United States)

    Forero-Romero, Jaime E.; Arias, Verónica

    2018-05-01

    We use simulations to build an analytic probability distribution for the asphericity in the satellite distribution around Local Group (LG) type galaxies in the Lambda Cold Dark Matter (LCDM) paradigm. We use this distribution to estimate the atypicality of the satellite distributions in the LG even when the underlying simulations do not have enough systems fully resembling the LG in terms of its typical masses, separation and kinematics. We demonstrate the method using three different simulations (Illustris-1, Illustris-1-Dark and ELVIS) and a number of satellites ranging from 11 to 15. Detailed results differ greatly among the simulations suggesting a strong influence of the typical DM halo mass, the number of satellites and the simulated baryonic effects. However, there are three common trends. First, at most 2% of the pairs are expected to have satellite distributions with the same asphericity as the LG; second, at most 80% of the pairs have a halo with a satellite distribution as aspherical as in M31; and third, at most 4% of the pairs have a halo with satellite distribution as planar as in the MW. These quantitative results place the LG at the level of a 3σ outlier in the LCDM paradigm. We suggest that understanding the reasons for this atypicality requires quantifying the asphericity probability distribution as a function of halo mass and large scale environment. The approach presented here can facilitate that kind of study and other comparisons between different numerical setups and choices to study satellites around LG pairs in simulations.

  20. Predicting Posttraumatic Stress Symptom Prevalence and Local Distribution after an Earthquake with Scarce Data.

    Science.gov (United States)

    Dussaillant, Francisca; Apablaza, Mauricio

    2017-08-01

    After a major earthquake, the assignment of scarce mental health emergency personnel to different geographic areas is crucial to the effective management of the crisis. The scarce information that is available in the aftermath of a disaster may be valuable in helping predict where are the populations that are in most need. The objectives of this study were to derive algorithms to predict posttraumatic stress (PTS) symptom prevalence and local distribution after an earthquake and to test whether there are algorithms that require few input data and are still reasonably predictive. A rich database of PTS symptoms, informed after Chile's 2010 earthquake and tsunami, was used. Several model specifications for the mean and centiles of the distribution of PTS symptoms, together with posttraumatic stress disorder (PTSD) prevalence, were estimated via linear and quantile regressions. The models varied in the set of covariates included. Adjusted R2 for the most liberal specifications (in terms of numbers of covariates included) ranged from 0.62 to 0.74, depending on the outcome. When only including peak ground acceleration (PGA), poverty rate, and household damage in linear and quadratic form, predictive capacity was still good (adjusted R2 from 0.59 to 0.67 were obtained). Information about local poverty, household damage, and PGA can be used as an aid to predict PTS symptom prevalence and local distribution after an earthquake. This can be of help to improve the assignment of mental health personnel to the affected localities. Dussaillant F , Apablaza M . Predicting posttraumatic stress symptom prevalence and local distribution after an earthquake with scarce data. Prehosp Disaster Med. 2017;32(4):357-367.

  1. Distributed embedded controller development with petri nets application to globally-asynchronous locally-synchronous systems

    CERN Document Server

    Moutinho, Filipe de Carvalho

    2016-01-01

    This book describes a model-based development approach for globally-asynchronous locally-synchronous distributed embedded controllers.  This approach uses Petri nets as modeling formalism to create platform and network independent models supporting the use of design automation tools.  To support this development approach, the Petri nets class in use is extended with time-domains and asynchronous-channels. The authors’ approach uses models not only providing a better understanding of the distributed controller and improving the communication among the stakeholders, but also to be ready to support the entire lifecycle, including the simulation, the verification (using model-checking tools), the implementation (relying on automatic code generators), and the deployment of the distributed controller into specific platforms. Uses a graphical and intuitive modeling formalism supported by design automation tools; Enables verification, ensuring that the distributed controller was correctly specified; Provides flex...

  2. Model-based monitoring techniques for leakage localization in distribution water networks

    OpenAIRE

    Meseguer Amela, Jordi; Mirats Tur, Josep Maria; Cembrano Gennari, Gabriela; Puig Cayuela, Vicenç

    2015-01-01

    This is an open access article under the CC BY-NC-ND license This paper describes an integrated model-based monitoring framework for leakage localization in district-metered areas (DMA) of water distribution networks, which takes advantage of the availability of a hydraulic model of the network. The leakage localization methodology is based on the use of flow and pressure sensors at the DMA inlets and a limited number of pressure sensors deployed inside the DMA. The placement of these sens...

  3. Post- and interseismic deformation due to both localized and distributed creep at depth (Invited)

    Science.gov (United States)

    Hetland, E. A.; Zhang, G.; Hines, T.

    2013-12-01

    There are two end-member representations of the ductile lithosphere (i.e., the lower crust and uppermost mantle) commonly used in models of post- and interseismic deformation around strike-slip faults: either (1) laterally homogeneous ductile layers, with sharp contrasts in rheological properties between the layers, in which creep is distributed; or (2) discrete extensions of the fault at depth in which creep is fully localized. The most realistic representation of the ductile lithosphere on earthquake cycle time scales likely falls between these two end-members. Researchers have considered both distributed and localized creep when interpreting post- and interseismic deformation, although the two mechanisms are most commonly treated separately, with the localized creep often approximated by kinematic slip on planar faults. There are a few noteworthy models that considered the feedback between both distributed and localized creep, although those models were largely constrained to 2D geometries of infinite length faults. The thickness of shear zones in the ductile lithosphere may be comparable to the locking depth of the fault, and the existence of a deep shear zone does not preclude the possibility that some distributed creep occurs in the surrounding lithosphere. Furthermore, variations in rheology, including both rheological models and their parameters, may be more subtle than the discrete contrasts typically assumed. In this presentation, we consider models of postseismic deformation following a finite length, strike-slip fault, as well as models of interseismic deformation around an infinite length strike-slip fault. Both sets of models are capable of localized and distributed creep at depth, and use Maxwell viscoelasticity. We show that the horizontal surface velocities during the early postseismic period are most sensitive to the viscosity of the shear zone; however during much of the interseismic period the shear zone is not apparent from the surface

  4. Distributed Classification of Localization Attacks in Sensor Networks Using Exchange-Based Feature Extraction and Classifier

    Directory of Open Access Journals (Sweden)

    Su-Zhe Wang

    2016-01-01

    Full Text Available Secure localization under different forms of attack has become an essential task in wireless sensor networks. Despite the significant research efforts in detecting the malicious nodes, the problem of localization attack type recognition has not yet been well addressed. Motivated by this concern, we propose a novel exchange-based attack classification algorithm. This is achieved by a distributed expectation maximization extractor integrated with the PECPR-MKSVM classifier. First, the mixed distribution features based on the probabilistic modeling are extracted using a distributed expectation maximization algorithm. After feature extraction, by introducing the theory from support vector machine, an extensive contractive Peaceman-Rachford splitting method is derived to build the distributed classifier that diffuses the iteration calculation among neighbor sensors. To verify the efficiency of the distributed recognition scheme, four groups of experiments were carried out under various conditions. The average success rate of the proposed classification algorithm obtained in the presented experiments for external attacks is excellent and has achieved about 93.9% in some cases. These testing results demonstrate that the proposed algorithm can produce much greater recognition rate, and it can be also more robust and efficient even in the presence of excessive malicious scenario.

  5. Distributed Fiber-Optic Sensor for Detection and Localization of Acoustic Vibrations

    Directory of Open Access Journals (Sweden)

    Sifta Radim

    2015-03-01

    Full Text Available A sensing system utilizing a standard optical fiber as a distributed sensor for the detection and localization of mechanical vibrations is presented. Vibrations can be caused by various external factors, like moving people, cars, trains, and other objects producing mechanical vibrations that are sensed by a fiber. In our laboratory we have designed a sensing system based on the Φ-OTDR (phase sensitive Optical Time Domain Reflectometry using an extremely narrow laser and EDFAs.

  6. Distributed collaborative processing in wireless sensor networks with application to target localization and beamforming

    OpenAIRE

    Béjar Haro, Benjamín

    2013-01-01

    Abstract The proliferation of wireless sensor networks and the variety of envisioned applications associated with them has motivated the development of distributed algorithms for collaborative processing over networked systems. One of the applications that has attracted the attention of the researchers is that of target localization where the nodes of the network try to estimate the position of an unknown target that lies within its coverage area. Particularly challenging is the problem of es...

  7. Harmonic Differential Quadrature Analysis of Soft-Core Sandwich Panels under Locally Distributed Loads

    Directory of Open Access Journals (Sweden)

    Xinwei Wang

    2016-11-01

    Full Text Available Sandwich structures are widely used in practice and thus various engineering theories adopting simplifying assumptions are available. However, most engineering theories of beams, plates and shells cannot recover all stresses accurately through their constitutive equations. Therefore, the soft-core is directly modeled by two-dimensional (2D elasticity theory without any pre-assumption on the displacement field. The top and bottom faces act like the elastic supports on the top and bottom edges of the core. The differential equations of the 2D core are then solved by the harmonic differential quadrature method (HDQM. To circumvent the difficulties in dealing with the locally distributed load by point discrete methods such as the HDQM, a general and rigorous way is proposed to treat the locally distributed load. Detailed formulations are provided. The static behavior of sandwich panels under different locally distributed loads is investigated. For verification, results are compared with data obtained by ABAQUS with very fine meshes. A high degree of accuracy on both displacement and stress has been observed.

  8. Application of Learning Methods to Local Electric Field Distributions in Defected Dielectric Materials

    Science.gov (United States)

    Ferris, Kim; Jones, Dumont

    2014-03-01

    Local electric fields reflect the structural and dielectric fluctuations in a semiconductor, and affect the material performance both for electron transport and carrier lifetime properties. In this paper, we use the LOCALF methodology with periodic boundary conditions to examine the local electric field distributions and its perturbations for II-VI (CdTe, Cd(1-x)Zn(x)Te) semiconductors, containing Te inclusions and small fluctuations in the local dielectric susceptibility. With inclusion of the induced-field term, the electric field distribution shows enhancements and diminishments compared to the macroscopic applied field, reflecting the microstructure characteristics of the dielectric. Learning methods are applied to these distributions to assess the spatial extent of the perturbation, and determine an electric field defined defect size as compared to its physical dimension. Critical concentrations of defects are assessed in terms of defect formation energies. This work was supported by the US Department of Homeland Security, Domestic Nuclear Detection Office, under competitively awarded contract/IAA HSHQDC-08-X-00872-e. This support does not constitute an express or implied endorsement on the part of the Gov't.

  9. Time distributions of recurrences of immunogenic and nonimmunogenic tumors following local irradiation

    International Nuclear Information System (INIS)

    Suit, H.D.; Sedlacek, R.; Fagundes, L.; Goitein, M.; Rothman, K.J.

    1978-01-01

    Three hundred and fourteen mice received single-dose irradiation of the right leg and thigh as treatment of an 8-mm mammary carcinoma isotransplant, and were then observed until death, usually by 1000 days. The time distributions of death due to local recurrence, radiation-induced sarcoma, distant metastasis in the absence of local regrowth, second primary, intercurrent disease, and unknown causes have been evaluated. The times for the transplant tumor inoculum to grow to an 8-mm tumor and the times of death due to local regrowth, distant metastasis, or induced tumor were all approximately log-normally distributed. Of the 128 recurrences, the latest-appearing 3 were at 300, 323, and 436 days; no recurrences were noted during the time period from 436 to 1000 days. These findings have been interpreted to mean that in some cases absolute cure of mice of the tumor in the leg was achieved by radiation alone at the dose levels employed. Radiation-induced sarcomas began to appear after 300 days. The time of appearance of the radiation-induced tumors was inversely related to radiation dose. Similar data for an immunogenic fibrosarcoma show that recurrences appeared earlier and were more closely bunched with respect to time than the recurrences of mammary carcinoma. The time distribution of the development of radiation-induced tumors in non-tumor-bearing animals was also approximately long-normally distributed; the slope of the time distribution curve was the same as that for radiation-induced tumors in mice which had been treated for tumor

  10. OPTIMIZATION OF THE POSITION OF THE LOCAL DISTRIBUTION CENTRE OF THE REGIONAL POST LOGISTICS NETWORK

    Directory of Open Access Journals (Sweden)

    Paweł DROŹDZIEL

    2017-09-01

    Full Text Available The phenomenon of the present postal services is the fact that, customers expect the lowest price while maintaining the availability, security and on time delivery of mail items. We can find that, the costs associated with transport of the postal substrate is one of the most important factors affecting the total cost of the postal services. These transport costs depend on various factors such as the investment in vehicles purchase, operational costs of the postal vehicles (costs of maintenance, repairs, fuel costs of the vehicle, etc. labour costs of the drivers and so on. For this reason, it is important to find such an operational - organizational solutions that can reduce the costs associated with the transportation of postal shipments, resulting in reducing the total cost of postal services. One option to do this is to minimize the length of postal transportation routes. This article presents the approach based on the application of graph theory to optimize existing connections of postal logistics network. Published results is oriented to revaluate existing position of local centre and find a location for the new local distribution centre potentially. New location of local distribution centre can to optimize (minimize the total transport costs of the local postal transportation network in area of the Lublin Province.

  11. Local multiplicity adjustment for the spatial scan statistic using the Gumbel distribution.

    Science.gov (United States)

    Gangnon, Ronald E

    2012-03-01

    The spatial scan statistic is an important and widely used tool for cluster detection. It is based on the simultaneous evaluation of the statistical significance of the maximum likelihood ratio test statistic over a large collection of potential clusters. In most cluster detection problems, there is variation in the extent of local multiplicity across the study region. For example, using a fixed maximum geographic radius for clusters, urban areas typically have many overlapping potential clusters, whereas rural areas have relatively few. The spatial scan statistic does not account for local multiplicity variation. We describe a previously proposed local multiplicity adjustment based on a nested Bonferroni correction and propose a novel adjustment based on a Gumbel distribution approximation to the distribution of a local scan statistic. We compare the performance of all three statistics in terms of power and a novel unbiased cluster detection criterion. These methods are then applied to the well-known New York leukemia dataset and a Wisconsin breast cancer incidence dataset. © 2011, The International Biometric Society.

  12. A Self-Organizing Incremental Neural Network based on local distribution learning.

    Science.gov (United States)

    Xing, Youlu; Shi, Xiaofeng; Shen, Furao; Zhou, Ke; Zhao, Jinxi

    2016-12-01

    In this paper, we propose an unsupervised incremental learning neural network based on local distribution learning, which is called Local Distribution Self-Organizing Incremental Neural Network (LD-SOINN). The LD-SOINN combines the advantages of incremental learning and matrix learning. It can automatically discover suitable nodes to fit the learning data in an incremental way without a priori knowledge such as the structure of the network. The nodes of the network store rich local information regarding the learning data. The adaptive vigilance parameter guarantees that LD-SOINN is able to add new nodes for new knowledge automatically and the number of nodes will not grow unlimitedly. While the learning process continues, nodes that are close to each other and have similar principal components are merged to obtain a concise local representation, which we call a relaxation data representation. A denoising process based on density is designed to reduce the influence of noise. Experiments show that the LD-SOINN performs well on both artificial and real-word data. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Evaluation of local power distribution with fine-mesh core model for the HTTR

    International Nuclear Information System (INIS)

    Murata, Isao; Yamashita, Kiyonobu; Maruyama, So; Shindo, Ryuichi; Fujimoto, Nozomu; Sudo, Yukio; Nakata, Tetsuo.

    1991-01-01

    An evaluation method of the local power distribution was developed considering the radial and axial heterogeneity caused by fuel rods, BP rods and block end graphite for the High Temperature Engineering Test Reactor (HTTR) in Japan Atomic Energy Research Institute (JAERI). The evaluation method was verified through the analyses of critical assembly experiments. A good agreement was obtained between calculations and measurements and the difference was less than 3 % on the power distribution. This method was applied to the core design for the HTTR to evaluate the maximum fuel temperature. From these results, it was confirmed that this evaluation method has an enough accuracy and is able to predict the detailed power distribution of the HTTR. (author)

  14. Correlation between local hemodynamics and lesion distribution in a novel aortic regurgitation murine model of atherosclerosis.

    Science.gov (United States)

    Hoi, Yiemeng; Zhou, Yu-Qing; Zhang, Xiaoli; Henkelman, R Mark; Steinman, David A

    2011-05-01

    Following surgical induction of aortic valve regurgitation (AR), extensive atherosclerotic plaque development along the descending thoracic and abdominal aorta of Ldlr⁻/⁻ mice has been reported, with distinct spatial distributions suggestive of a strong local hemodynamic influence. The objective of this study was to test, using image-based computational fluid dynamics (CFD), whether this is indeed the case. The lumen geometry was reconstructed from micro-CT scanning of a control Ldlr⁻/⁻ mouse, and CFD simulations were carried out for both AR and control flow conditions derived from Doppler ultrasound measurements and literature data. Maps of time-averaged wall shear stress magnitude (TAWSS), oscillatory shear index (OSI) and relative residence time (RRT) were compared against the spatial distributions of plaque stained with oil red O, previously acquired in a group of AR and control mice. Maps of OSI and RRT were found to be consistent with plaque distributions in the AR mice and the absence of plaque in the control mice. TAWSS was uniformly lower under control vs. AR flow conditions, suggesting that levels (> 100 dyn/cm²) exceeded those required to alone induce a pro-atherogenic response. Simulations of a straightened CFD model confirmed the importance of anatomical curvature for explaining the spatial distribution of lesions in the AR mice. In summary, oscillatory and retrograde flow induced in the AR mice, without concomitant low shear, may exacerbate or accelerate lesion formation, but the distinct anatomical curvature of the mouse aorta is responsible for the spatial distribution of lesions.

  15. Distributed Water Pollution Source Localization with Mobile UV-Visible Spectrometer Probes in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Junjie Ma

    2018-02-01

    Full Text Available Pollution accidents that occur in surface waters, especially in drinking water source areas, greatly threaten the urban water supply system. During water pollution source localization, there are complicated pollutant spreading conditions and pollutant concentrations vary in a wide range. This paper provides a scalable total solution, investigating a distributed localization method in wireless sensor networks equipped with mobile ultraviolet-visible (UV-visible spectrometer probes. A wireless sensor network is defined for water quality monitoring, where unmanned surface vehicles and buoys serve as mobile and stationary nodes, respectively. Both types of nodes carry UV-visible spectrometer probes to acquire in-situ multiple water quality parameter measurements, in which a self-adaptive optical path mechanism is designed to flexibly adjust the measurement range. A novel distributed algorithm, called Dual-PSO, is proposed to search for the water pollution source, where one particle swarm optimization (PSO procedure computes the water quality multi-parameter measurements on each node, utilizing UV-visible absorption spectra, and another one finds the global solution of the pollution source position, regarding mobile nodes as particles. Besides, this algorithm uses entropy to dynamically recognize the most sensitive parameter during searching. Experimental results demonstrate that online multi-parameter monitoring of a drinking water source area with a wide dynamic range is achieved by this wireless sensor network and water pollution sources are localized efficiently with low-cost mobile node paths.

  16. Distributed Water Pollution Source Localization with Mobile UV-Visible Spectrometer Probes in Wireless Sensor Networks.

    Science.gov (United States)

    Ma, Junjie; Meng, Fansheng; Zhou, Yuexi; Wang, Yeyao; Shi, Ping

    2018-02-16

    Pollution accidents that occur in surface waters, especially in drinking water source areas, greatly threaten the urban water supply system. During water pollution source localization, there are complicated pollutant spreading conditions and pollutant concentrations vary in a wide range. This paper provides a scalable total solution, investigating a distributed localization method in wireless sensor networks equipped with mobile ultraviolet-visible (UV-visible) spectrometer probes. A wireless sensor network is defined for water quality monitoring, where unmanned surface vehicles and buoys serve as mobile and stationary nodes, respectively. Both types of nodes carry UV-visible spectrometer probes to acquire in-situ multiple water quality parameter measurements, in which a self-adaptive optical path mechanism is designed to flexibly adjust the measurement range. A novel distributed algorithm, called Dual-PSO, is proposed to search for the water pollution source, where one particle swarm optimization (PSO) procedure computes the water quality multi-parameter measurements on each node, utilizing UV-visible absorption spectra, and another one finds the global solution of the pollution source position, regarding mobile nodes as particles. Besides, this algorithm uses entropy to dynamically recognize the most sensitive parameter during searching. Experimental results demonstrate that online multi-parameter monitoring of a drinking water source area with a wide dynamic range is achieved by this wireless sensor network and water pollution sources are localized efficiently with low-cost mobile node paths.

  17. Multi-isocenter stereotactic radiotherapy: implications for target dose distributions of systematic and random localization errors

    International Nuclear Information System (INIS)

    Ebert, M.A.; Zavgorodni, S.F.; Kendrick, L.A.; Weston, S.; Harper, C.S.

    2001-01-01

    Purpose: This investigation examined the effect of alignment and localization errors on dose distributions in stereotactic radiotherapy (SRT) with arced circular fields. In particular, it was desired to determine the effect of systematic and random localization errors on multi-isocenter treatments. Methods and Materials: A research version of the FastPlan system from Surgical Navigation Technologies was used to generate a series of SRT plans of varying complexity. These plans were used to examine the influence of random setup errors by recalculating dose distributions with successive setup errors convolved into the off-axis ratio data tables used in the dose calculation. The influence of systematic errors was investigated by displacing isocenters from their planned positions. Results: For single-isocenter plans, it is found that the influences of setup error are strongly dependent on the size of the target volume, with minimum doses decreasing most significantly with increasing random and systematic alignment error. For multi-isocenter plans, similar variations in target dose are encountered, with this result benefiting from the conventional method of prescribing to a lower isodose value for multi-isocenter treatments relative to single-isocenter treatments. Conclusions: It is recommended that the systematic errors associated with target localization in SRT be tracked via a thorough quality assurance program, and that random setup errors be minimized by use of a sufficiently robust relocation system. These errors should also be accounted for by incorporating corrections into the treatment planning algorithm or, alternatively, by inclusion of sufficient margins in target definition

  18. Study of Climate Change Impact to Local Rainfall Distribution in Lampung Provinces

    Directory of Open Access Journals (Sweden)

    Tumiar Katarina Manik

    2016-08-01

    Full Text Available Global warming which leads to climate change has potential affect to Indonesia agriculture activities and production. Analyzing rainfall pattern and distribution is important to investigate the impact of global climate change to local climate. This study using rainfall data from 1976-2010 from both lowland and upland area of Lampung Province. The results show that rainfall tends to decrease since the 1990s which related to the years with El Nino event. Monsoonal pattern- having rain and dry season- still excist in Lampung; however, since most rain fell below the average, it could not meet crops water need. Farmers conclude that dry seasons were longer and seasonal pattern has been changed. Global climate change might affect Lampung rainfall distribution through changes on sea surface temperature which could intensify the El Nino effect. Therefore, watching the El Nino phenomena and how global warming affects it, is important in predicting local climate especially the rainfall distribution in order to prevent significant loss in agriculture productivities.

  19. Detection prospects for high energy neutrino sources from the anisotropic matter distribution in the local Universe

    Energy Technology Data Exchange (ETDEWEB)

    Mertsch, Philipp; Rameez, Mohamed; Tamborra, Irene, E-mail: mertsch@nbi.ku.dk, E-mail: mohamed.rameez@nbi.ku.dk, E-mail: tamborra@nbi.ku.dk [Niels Bohr International Academy, Niels Bohr Institute, Blegdamsvej 17, 2100 Copenhagen (Denmark)

    2017-03-01

    Constraints on the number and luminosity of the sources of the cosmic neutrinos detected by IceCube have been set by targeted searches for point sources. We set complementary constraints by using the 2MASS Redshift Survey (2MRS) catalogue, which maps the matter distribution of the local Universe. Assuming that the distribution of the neutrino sources follows that of matter, we look for correlations between ''warm'' spots on the IceCube skymap and the 2MRS matter distribution. Through Monte Carlo simulations of the expected number of neutrino multiplets and careful modelling of the detector performance (including that of IceCube-Gen2), we demonstrate that sources with local density exceeding 10{sup −6} Mpc{sup −3} and neutrino luminosity L {sub ν} ∼< 10{sup 42} erg s{sup −1} (10{sup 41} erg s{sup −1}) will be efficiently revealed by our method using IceCube (IceCube-Gen2). At low luminosities such as will be probed by IceCube-Gen2, the sensitivity of this analysis is superior to requiring statistically significant direct observation of a point source.

  20. Experience of BESIII data production with local cluster and distributed computing model

    International Nuclear Information System (INIS)

    Deng, Z Y; Li, W D; Liu, H M; Sun, Y Z; Zhang, X M; Lin, L; Nicholson, C; Zhemchugov, A

    2012-01-01

    The BES III detector is a new spectrometer which works on the upgraded high-luminosity collider, BEPCII. The BES III experiment studies physics in the tau-charm energy region from 2 GeV to 4.6 GeV . From 2009 to 2011, BEPCII has produced 106M ψ(2S) events, 225M J/ψ events, 2.8 fb −1 ψ(3770) data, and 500 pb −1 data at 4.01 GeV. All the data samples were processed successfully and many important physics results have been achieved based on these samples. Doing data production correctly and efficiently with limited CPU and storage resources is a big challenge. This paper will describe the implementation of the experiment-specific data production for BESIII in detail, including data calibration with event-level parallel computing model, data reconstruction, inclusive Monte Carlo generation, random trigger background mixing and multi-stream data skimming. Now, with the data sample increasing rapidly, there is a growing demand to move from solely using a local cluster to a more distributed computing model. A distributed computing environment is being set up and expected to go into production use in 2012. The experience of BESIII data production, both with a local cluster and with a distributed computing model, is presented here.

  1. Distributed Input and State Estimation Using Local Information in Heterogeneous Sensor Networks

    Directory of Open Access Journals (Sweden)

    Dzung Tran

    2017-07-01

    Full Text Available A new distributed input and state estimation architecture is introduced and analyzed for heterogeneous sensor networks. Specifically, nodes of a given sensor network are allowed to have heterogeneous information roles in the sense that a subset of nodes can be active (that is, subject to observations of a process of interest and the rest can be passive (that is, subject to no observation. Both fixed and varying active and passive roles of sensor nodes in the network are investigated. In addition, these nodes are allowed to have non-identical sensor modalities under the common underlying assumption that they have complimentary properties distributed over the sensor network to achieve collective observability. The key feature of our framework is that it utilizes local information not only during the execution of the proposed distributed input and state estimation architecture but also in its design in that global uniform ultimate boundedness of error dynamics is guaranteed once each node satisfies given local stability conditions independent from the graph topology and neighboring information of these nodes. As a special case (e.g., when all nodes are active and a positive real condition is satisfied, the asymptotic stability can be achieved with our algorithm. Several illustrative numerical examples are further provided to demonstrate the efficacy of the proposed architecture.

  2. Addressing potential local adaptation in species distribution models: implications for conservation under climate change

    Science.gov (United States)

    Hällfors, Maria Helena; Liao, Jishan; Dzurisin, Jason D. K.; Grundel, Ralph; Hyvärinen, Marko; Towle, Kevin; Wu, Grace C.; Hellmann, Jessica J.

    2016-01-01

    Species distribution models (SDMs) have been criticized for involving assumptions that ignore or categorize many ecologically relevant factors such as dispersal ability and biotic interactions. Another potential source of model error is the assumption that species are ecologically uniform in their climatic tolerances across their range. Typically, SDMs to treat a species as a single entity, although populations of many species differ due to local adaptation or other genetic differentiation. Not taking local adaptation into account, may lead to incorrect range prediction and therefore misplaced conservation efforts. A constraint is that we often do not know the degree to which populations are locally adapted, however. Lacking experimental evidence, we still can evaluate niche differentiation within a species' range to promote better conservation decisions. We explore possible conservation implications of making type I or type II errors in this context. For each of two species, we construct three separate MaxEnt models, one considering the species as a single population and two of disjunct populations. PCA analyses and response curves indicate different climate characteristics in the current environments of the populations. Model projections into future climates indicate minimal overlap between areas predicted to be climatically suitable by the whole species versus population-based models. We present a workflow for addressing uncertainty surrounding local adaptation in SDM application and illustrate the value of conducting population-based models to compare with whole-species models. These comparisons might result in more cautious management actions when alternative range outcomes are considered.

  3. Compressing Sensing Based Source Localization for Controlled Acoustic Signals Using Distributed Microphone Arrays

    Directory of Open Access Journals (Sweden)

    Wei Ke

    2017-01-01

    Full Text Available In order to enhance the accuracy of sound source localization in noisy and reverberant environments, this paper proposes an adaptive sound source localization method based on distributed microphone arrays. Since sound sources lie at a few points in the discrete spatial domain, our method can exploit this inherent sparsity to convert the localization problem into a sparse recovery problem based on the compressive sensing (CS theory. In this method, a two-step discrete cosine transform- (DCT- based feature extraction approach is utilized to cover both short-time and long-time properties of acoustic signals and reduce the dimensions of the sparse model. In addition, an online dictionary learning (DL method is used to adjust the dictionary for matching the changes of audio signals, and then the sparse solution could better represent location estimations. Moreover, we propose an improved block-sparse reconstruction algorithm using approximate l0 norm minimization to enhance reconstruction performance for sparse signals in low signal-noise ratio (SNR conditions. The effectiveness of the proposed scheme is demonstrated by simulation results and experimental results where substantial improvement for localization performance can be obtained in the noisy and reverberant conditions.

  4. Impact of localized microwave hyperthermia on the pH-distribution in malignant tumors

    International Nuclear Information System (INIS)

    Vaupel, P.

    1982-01-01

    The impact of localized microwave hyperthermia (2.45 GHz) on the tissue pH-distribution was investigated in C3H mause mammary tumors. The measurements were performed in microareas of the tissue using pH-microelectrodes with tip diameters of approximately 1 μm. pH-readings during localized heating revealed that tissue temperatures exceeding 42 0 C were followed by a pronounced pH-drop in tumors with a negligible amount of necrosis. Tissue pH-values measured immediately after heating (43 0 C for 60 min) were lowered by an average of 0.54 +- 0.19 pH-units as compared with preheating data (2p [de

  5. Local Voltage Control in Distribution Networks: A Game-Theoretic Perspective

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Xinyang; Tian, Jie; Chen, Lijun; Dall' Anese, Emiliano

    2016-11-21

    Inverter-based voltage regulation is gaining importance to alleviate emerging reliability and power-quality concerns related to distribution systems with high penetration of photovoltaic (PV) systems. This paper seeks contribution in the domain of reactive power compensation by establishing stability of local Volt/VAr controllers. In lieu of the approximate linear surrogate used in the existing work, the paper establishes existence and uniqueness of an equilibrium point using nonlinear AC power flow model. Key to this end is to consider a nonlinear dynamical system with non-incremental local Volt/VAr control, cast the Volt/VAr dynamics as a game, and leverage the fixed-point theorem as well as pertinent contraction mapping argument. Numerical examples are provided to complement the analytical results.

  6. Highly localized distributed Brillouin scattering response in a photonic integrated circuit

    Science.gov (United States)

    Zarifi, Atiyeh; Stiller, Birgit; Merklein, Moritz; Li, Neuton; Vu, Khu; Choi, Duk-Yong; Ma, Pan; Madden, Stephen J.; Eggleton, Benjamin J.

    2018-03-01

    The interaction of optical and acoustic waves via stimulated Brillouin scattering (SBS) has recently reached on-chip platforms, which has opened new fields of applications ranging from integrated microwave photonics and on-chip narrow-linewidth lasers, to phonon-based optical delay and signal processing schemes. Since SBS is an effect that scales exponentially with interaction length, on-chip implementation on a short length scale is challenging, requiring carefully designed waveguides with optimized opto-acoustic overlap. In this work, we use the principle of Brillouin optical correlation domain analysis to locally measure the SBS spectrum with high spatial resolution of 800 μm and perform a distributed measurement of the Brillouin spectrum along a spiral waveguide in a photonic integrated circuit. This approach gives access to local opto-acoustic properties of the waveguides, including the Brillouin frequency shift and linewidth, essential information for the further development of high quality photonic-phononic waveguides for SBS applications.

  7. Self-Intersection Local Times of Generalized Mixed Fractional Brownian Motion as White Noise Distributions

    International Nuclear Information System (INIS)

    Suryawan, Herry P.; Gunarso, Boby

    2017-01-01

    The generalized mixed fractional Brownian motion is defined by taking linear combinations of a finite number of independent fractional Brownian motions with different Hurst parameters. It is a Gaussian process with stationary increments, posseses self-similarity property, and, in general, is neither a Markov process nor a martingale. In this paper we study the generalized mixed fractional Brownian motion within white noise analysis framework. As a main result, we prove that for any spatial dimension and for arbitrary Hurst parameter the self-intersection local times of the generalized mixed fractional Brownian motions, after a suitable renormalization, are well-defined as Hida white noise distributions. The chaos expansions of the self-intersection local times in the terms of Wick powers of white noises are also presented. (paper)

  8. Local Voltage Control in Distribution Networks: A Game-Theoretic Perspective: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Xinyang; Tian, Jie; Chen, Lijun; Dall' Anese, Emiliano

    2016-09-01

    Inverter-based voltage regulation is gaining importance to alleviate emerging reliability and power-quality concerns related to distribution systems with high penetration of photovoltaic (PV) systems. This paper seeks contribution in the domain of reactive power compensation by establishing stability of local Volt/VAr controllers. In lieu of the approximate linear surrogate used in the existing work, the paper establishes existence and uniqueness of an equilibrium point using nonlinear AC power flow model. Key to this end is to consider a nonlinear dynamical system with non-incremental local Volt/VAr control, cast the Volt/VAr dynamics as a game, and leverage the fixed-point theorem as well as pertinent contraction mapping argument. Numerical examples are provided to complement the analytical results.

  9. Distribution and localization of the harmonic magnon modes in a one-dimensional Heisenberg spin glass

    Science.gov (United States)

    Boukahil, A.; Huber, D. L.

    1989-09-01

    The harmonic magnon modes in a one-dimensional Heisenberg spin glass having nearest-neighbor exchange interactions of fixed magnitude and random sign are investigated. The Lyapounov exponent is calculated for chains of 107-108 spins over the interval 0Stinchcombe and Pimentel using transfer-matrix techniques; at higher frequencies, gaps appear in the spectrum. At low frequencies, the localization length diverges as ω-2/3. A formal connection is established between the spin glass and the one-dimensional discretized Schrödinger equation. By making use of the connection, it is shown that the theory of Derrida and Gardner, which was developed for weak potential disorder, can account quantitatively for the distribution and localization of the low-frequency magnon modes in the spin-glass model.

  10. Evolution of the distribution of baryons in a simulated Local Group Universe

    Science.gov (United States)

    Peirani, S.

    2012-12-01

    Using hydrodynamical zoom simulations in the standard ΛCDM cosmology, we have investigated the evolution of the distribution of baryons (gas and stars) in a local group-type universe. We found that physical mechanisms able to drive the gas out of the virial radius at high redshifts (such as AGN) will have a stronger impact on the deficit of baryons in the mass budget of Milky Way type-galaxies at present times than those that expel the gas in the longer, late phases of galaxy formation.

  11. Experimental validation of a distributed algorithm for dynamic spectrum access in local area networks

    DEFF Research Database (Denmark)

    Tonelli, Oscar; Berardinelli, Gilberto; Tavares, Fernando Menezes Leitão

    2013-01-01

    Next generation wireless networks aim at a significant improvement of the spectral efficiency in order to meet the dramatic increase in data service demand. In local area scenarios user-deployed base stations are expected to take place, thus making the centralized planning of frequency resources...... activities with the Autonomous Component Carrier Selection (ACCS) algorithm, a distributed solution for interference management among small neighboring cells. A preliminary evaluation of the algorithm performance is provided considering its live execution on a software defined radio network testbed...

  12. Non--Local Approach to the Analysis of the Stress Distribution in Granular Systems.

    Science.gov (United States)

    Scott, J. E.; Kenkre, V. M.; Hurd, A. J.

    1998-03-01

    A continuum mechanical theory of the stress distribution in granular materials is presented, where the transformation of the vertical spatial coordinate into a formal time variable converts the study of the static stress distribution into a generally non--Markoffian, i.e., memory-possessing (non-local) propagation analysis. Previous treatments (J. -P). Bouchaud, M. E. Cates, and P. Claudin, J. Phys. I France 5, 639 (1995). (C. -h). Liu, S. R. Nagel, D. A. Schecter, S. N. Coppersmith, S. Majumdar, O. Narayan, and T. A. Witten, Science 269, 513 (1995). are shown to be particular cases of our theory corresponding to, respectively, wave-like and dif fusive limits of the general evolution. Calculations are presented for the example of ceramic or metal powder compaction in dies, with emphasis on the understanding of previously unexplained features as seen in experimental data found in the literature o ver the past 50 years. Specific proposals for new experimental investigations are presented.

  13. A voting-based star identification algorithm utilizing local and global distribution

    Science.gov (United States)

    Fan, Qiaoyun; Zhong, Xuyang; Sun, Junhua

    2018-03-01

    A novel star identification algorithm based on voting scheme is presented in this paper. In the proposed algorithm, the global distribution and local distribution of sensor stars are fully utilized, and the stratified voting scheme is adopted to obtain the candidates for sensor stars. The database optimization is employed to reduce its memory requirement and improve the robustness of the proposed algorithm. The simulation shows that the proposed algorithm exhibits 99.81% identification rate with 2-pixel standard deviations of positional noises and 0.322-Mv magnitude noises. Compared with two similar algorithms, the proposed algorithm is more robust towards noise, and the average identification time and required memory is less. Furthermore, the real sky test shows that the proposed algorithm performs well on the real star images.

  14. Large developing receptive fields using a distributed and locally reprogrammable address-event receiver.

    Science.gov (United States)

    Bamford, Simeon A; Murray, Alan F; Willshaw, David J

    2010-02-01

    A distributed and locally reprogrammable address-event receiver has been designed, in which incoming address-events are monitored simultaneously by all synapses, allowing for arbitrarily large axonal fan-out without reducing channel capacity. Synapses can change the address of their presynaptic neuron, allowing the distributed implementation of a biologically realistic learning rule, with both synapse formation and elimination (synaptic rewiring). Probabilistic synapse formation leads to topographic map development, made possible by a cross-chip current-mode calculation of Euclidean distance. As well as synaptic plasticity in rewiring, synapses change weights using a competitive Hebbian learning rule (spike-timing-dependent plasticity). The weight plasticity allows receptive fields to be modified based on spatio-temporal correlations in the inputs, and the rewiring plasticity allows these modifications to become embedded in the network topology.

  15. Microstructure and Ultrastructure Alterations in the Pallium of Immature Mice Exposed to Cadmium.

    Science.gov (United States)

    Yang, X F; Han, Q G; Liu, D Y; Zhang, H T; Fan, G Y; Ma, J Y; Wang, Z L

    2016-11-01

    The aim of this study was to investigate microstructure and ultrastructure alterations in the pallium of immature mice exposed to cadmium. Forty immature mice were randomly divided into control, 1/100 LD 50 (1.87 mg/kg, low), 1/50 LD 50 (3.74 mg/kg, medium), and 1/25 LD 50 (7.48 mg/kg, high) dose groups. After oral cadmium exposure for 40 days, the pallium of mice was obtained for microstructure and ultrastructure studies. The results showed that both microstructure and ultrastructure alterations of the pallium were observed in all treated mice and the most obvious alterations were in the high dose group. Microstructural analysis showed seriously congested capillary in the pia mater of the pallium in the high cadmium group. Meanwhile, vacuolar degenerate or karyopyknosis presented in some neurocytes, capillary quantity, and the number of apoptotic cells increased, some neurocytes became hypertrophy, the pia mater separated from the cortex, and local hemorrhage and accompanied inflammatory cell infiltration were also observed. Ultrastructural analysis showed that rough endoplasmic reticulum was expanded, heterochromatin marginalized, perinuclear space distinctly broadened, swelling and vacuolization mitochondria appeared, synapse was swelling, presynaptic and postsynaptic membranes presented fusion, and most of mitochondrial cristae were ambiguous. The results indicated that cadmium exposure for 40 days induced dose-dependent microstructure and ultrastructure alterations in pallium of immature mice.

  16. The reorganization of root anatomy and ultrastructure of syncytial cells in tomato (Lycopersicon esculentum Mill. infected with potato cyst nematode (Globodera rostochiensis Woll.

    Directory of Open Access Journals (Sweden)

    Sylwia Fudali

    2011-01-01

    Full Text Available The sequence of anatomical and ultrastructural events leading to the syncytium development in tomato roots infected with Globodera rostochiensis was examined. The syncytia were preferentially induced in cortical or pericyclic cells in the elongation zone of root. They developed towards the vascular cylinder by incorporation of new cells via local cell wall breakdown. After surrounding primary phloem bundle and reaching xylem tracheary elements syncytia spread along vascular cylinder. Roots in primary state of growth seemed to be the best place for syncytium induction as syncytia formed in the zone of secondary growth were less hypertrophied. At the ultrastructural level syncytial elements were characterized by strong hypertrophy, breakdown of central vacuole, increased volume of cytoplasm, proliferation of organelles, and enlargement of nuclei. On the syncytial wall adjoining vessels the cell wall ingrowths were formed, while the syncytial walls at interface of phloem were considerably thickened. They lacked of functional plasmodesmata and did not form any ingrowths. Using immunofluorescent-labelling and immunogold-labelling methods tomato expansin 5 protein was localized in nematode infected roots. The distribution of LeEXP A5 was restricted only to the walls of syncytia. The protein distribution pattern indicated that LeEXP A5 could mediates cell wall expansion during hypertrophy of syncytial elements.

  17. Ultrastructural features of the internodes’ surface in horsetail (Equisetum arvense L.

    Directory of Open Access Journals (Sweden)

    Myroslava Stakhiv

    2013-04-01

    Full Text Available The ultrastructure of the outer surface of the common horsetail stem was studied. Through electron microscopic analysis we showed that silica plates on the surface of Equisetum arvense L. stem are distributed evenly, not tight, in thin layer. Thus, compact arrangement of particles on the internodes causes high mechanical strength and stiffness of the E. arvensestem and lateral branches.

  18. Distribution and absorption of local anesthetics in inferior alveolar nerve block: evaluation by magnetic resonance imaging.

    Science.gov (United States)

    Ay, Sinan; Küçük, Dervisşhan; Gümüş, Cesur; Kara, M Isa

    2011-11-01

    The aim of this study was to evaluate the distribution and absorption of local anesthetic solutions in inferior alveolar nerve block using magnetic resonance imaging. Forty healthy volunteers were divided into 4 groups and injected with 1.5 mL for inferior alveolar nerve block and 0.3 mL for lingual nerve block. The solutions used for the different groups were 2% lidocaine, 2% lidocaine with 0.125 mg/mL epinephrine, 4% articaine with 0.006 mg/mL epinephrine, and 4% articaine with 0.012 mg/mL epinephrine. All subjects had axial T2-weighted and fat-suppressed images at 0, 60, and 120 minutes after injection. The localization, area, and intensity (signal characteristics) of the solutions were analyzed and onset and duration times of the anesthesia were recorded. There were no significant differences between groups with regard to the intensity and area of the solutions at 0, 60, and 120 minutes after injection, but differences were found within each group. No between-group differences were found on magnetic resonance imaging in the distribution and absorption of lidocaine with or without epinephrine and articaine with 0.006 and 0.012 mg/mL epinephrine. All solutions were noticeably absorbed at 120 minutes after injection. Copyright © 2011 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  19. Community financing of local ivermectin distribution in Nigeria: potential payment and cost-recovery outlook.

    Science.gov (United States)

    Onwujekwe, O E; Shu, E N; Okonkwo, P O

    2000-04-01

    The preferred payment mechanism in a community financing scheme for local ivermectin distribution was elicited from randomly selected household heads from three communities in Nigeria using interviewer-administered structured questionnaires. The majority of the respondents in the three communities were prepared to pay for local ivermectin distribution. Additionally, the average amounts the respondents were prepared to pay per person treated ($0.28, $0.30 and $0.38 in Nike, Achi and Toro, respectively) were all more than the $0.20 ceiling recommended by the partners of the African Programme on Onchocerciasis Control (APOC). Thus, the cost-recovery outlook is bright in these communities. However, the preferred payment modality varied. Fee-for-service was the predominant payment modality in the Achi and Nike communities, while the Toro community preferred pre-payment. This study demonstrates that many communities have different payment preferences for endemic disease control efforts. This knowledge will help in developing acceptable and sustainable schemes. The imposition of unacceptable payment mechanisms will lead to an unwillingness to pay.

  20. Interpreting dark matter direct detection independently of the local velocity and density distribution

    International Nuclear Information System (INIS)

    Fox, Patrick J.; Kribs, Graham D.; Tait, Tim M. P.

    2011-01-01

    We demonstrate precisely what particle physics information can be extracted from a single direct detection observation of dark matter while making absolutely no assumptions about the local velocity distribution and local density of dark matter. Our central conclusions follow from a very simple observation: the velocity distribution of dark matter is positive definite, f(v)≥0. We demonstrate the utility of this result in several ways. First, we show a falling deconvoluted recoil spectrum (deconvoluted of the nuclear form factor), such as from ordinary elastic scattering, can be 'mocked up' by any mass of dark matter above a kinematic minimum. As an example, we show that dark matter much heavier than previously considered can explain the CoGeNT excess. Specifically, m χ Ge can be in just as good agreement as light dark matter, while m χ >m Ge depends on understanding the sensitivity of xenon to dark matter at very low recoil energies, E R < or approx. 6 keVnr. Second, we show that any rise in the deconvoluted recoil spectrum represents distinct particle physics information that cannot be faked by an arbitrary f(v). As examples of resulting nontrivial particle physics, we show that inelastic dark matter and dark matter with a form factor can both yield such a rise.

  1. Stabilization analysis of Euler-Bernoulli beam equation with locally distributed disturbance

    Directory of Open Access Journals (Sweden)

    Pengcheng HAN

    2017-12-01

    Full Text Available In order to enrich the system stability theory of the control theories, taking Euler-Bernoulli beam equation as the research subject, the stability of Euler-Bernoulli beam equation with locally distributed disturbance is studied. A feedback controller based on output is designed to reduce the effects of the disturbances. The well-posedness of the nonlinear closed-loop system is investigated by the theory of maximal monotone operator, namely the existence and uniqueness of solutions for the closed-loop system. An appropriate state space is established, an appropriate inner product is defined, and a non-linear operator satisfying this state space is defined. Then, the system is transformed into the form of evolution equation. Based on this, the existence and uniqueness of solutions for the closed-loop system are proved. The asymptotic stability of the system is studied by constructing an appropriate Lyapunov function, which proves the asymptotic stability of the closed-loop system. The result shows that designing proper anti-interference controller is the foundation of investigating the system stability, and the research of the stability of Euler-bernoulli beam equation with locally distributed disturbance can prove the asymptotic stability of the system. This method can be extended to study the other equations such as wave equation, Timoshenko beam equation, Schrodinger equation, etc.

  2. THE STRESS STATE OF THE RADIALLY INHOMOGENEOUS HEMISPHERICAL SHELL UNDER LOCALLY DISTRIBUTED VERTICAL LOAD

    Directory of Open Access Journals (Sweden)

    Andreev Vladimir Igorevich

    2018-01-01

    Full Text Available Subject: one of the promising trends in the development of structural mechanics is the development of methods for solving problems in the theory of elasticity for bodies with continuous inhomogeneity of any deformation characteristics: these methods make it possible to use the strength of the material most fully. In this paper, we consider the two-dimensional problem for the case when a vertical, locally distributed load acts on the hemisphere and the inhomogeneity is caused by the influence of the temperature field. Research objectives: derive governing system of equations in spherical coordinates for determination of the stress state of the radially inhomogeneous hemispherical shell under locally distributed vertical load. Materials and methods: as a mechanical model, we chose a thick-walled reinforced concrete shell (hemisphere with inner and outer radii a and b, respectively, b > a. The shell’s parameters are a = 3.3 m, b = 4.5 m, Poisson’s ratio ν = 0.16; the load parameters are f = 10MPa - vertical localized load distributed over the outer face, θ0 = 30°, temperature on the internal surface of the shell Ta = 500 °C, temperature on the external surface of the shell Tb = 0 °C. The resulting boundary-value problem (a system of differential equations with variable coefficients is solved using the Maple software package. Results: maximal compressive stresses σr with allowance for material inhomogeneity are reduced by 10 % compared with the case when the inhomogeneity is ignored. But it is not so important compared with a 3-fold decrease in the tensile stress σθ on the inner surface and a 2-fold reduction in the tensile stress σθ on the outer surface of the hemisphere as concretes generally have a tensile strength substantially smaller than the compressive strength. Conclusions: the method presented in this article makes it possible to reduce the deformation characteristics of the material, i.e. it leads to a reduction in stresses

  3. Automated local bright feature image analysis of nuclear protein distribution identifies changes in tissue phenotype

    International Nuclear Information System (INIS)

    Knowles, David; Sudar, Damir; Bator, Carol; Bissell, Mina

    2006-01-01

    The organization of nuclear proteins is linked to cell and tissue phenotypes. When cells arrest proliferation, undergo apoptosis, or differentiate, the distribution of nuclear proteins changes. Conversely, forced alteration of the distribution of nuclear proteins modifies cell phenotype. Immunostaining and fluorescence microscopy have been critical for such findings. However, there is an increasing need for quantitative analysis of nuclear protein distribution to decipher epigenetic relationships between nuclear structure and cell phenotype, and to unravel the mechanisms linking nuclear structure and function. We have developed imaging methods to quantify the distribution of fluorescently-stained nuclear protein NuMA in different mammary phenotypes obtained using three-dimensional cell culture. Automated image segmentation of DAPI-stained nuclei was generated to isolate thousands of nuclei from three-dimensional confocal images. Prominent features of fluorescently-stained NuMA were detected using a novel local bright feature analysis technique, and their normalized spatial density calculated as a function of the distance from the nuclear perimeter to its center. The results revealed marked changes in the distribution of the density of NuMA bright features as non-neoplastic cells underwent phenotypically normal acinar morphogenesis. In contrast, we did not detect any reorganization of NuMA during the formation of tumor nodules by malignant cells. Importantly, the analysis also discriminated proliferating non-neoplastic cells from proliferating malignant cells, suggesting that these imaging methods are capable of identifying alterations linked not only to the proliferation status but also to the malignant character of cells. We believe that this quantitative analysis will have additional applications for classifying normal and pathological tissues

  4. HERUS: the far-IR/submm spectral energy distributions of local ULIRGs and photometric atlas

    Science.gov (United States)

    Clements, D. L.; Pearson, C.; Farrah, D.; Greenslade, J.; Bernard-Salas, Jeronimo; González-Alfonso, E.; Afonso, J.; Efstathiou, A.; Rigopoulou, D.; Lebouteiller, V.; Hurley, P. D.; Spoon, H.

    2018-04-01

    We present the Herschel-SPIRE photometric atlas for a complete flux limited sample of 43 local ultraluminous infrared galaxies (ULIRGs), selected at 60 μm by IRAS, as part of the HERschel ULIRG Survey (HERUS). Photometry observations were obtained using the SPIRE instrument at 250, 350, and 500 μm. We describe these observations, present the results, and combine the new observations with data from IRAS to examine the far-infrared spectral energy distributions (SEDs) of these sources. We fit the observed SEDs of HERUS objects with a simple parametrized modified blackbody model, where temperature and emissivity β are free parameters. We compare the fitted values to those of non-ULIRG local galaxies, and find, in agreement with earlier results, that HERUS ULIRGs have warmer dust (median temperature T = 37.9 ± 4.7 K compared to 21.3 ± 3.4 K) but a similar β distribution (median β = 1.7 compared to 1.8) to the Herschel reference sample (HRS, Cortese et al. 2014) galaxies. Dust masses are found to be in the range of 107.5-109 M⊙, significantly higher than that of HRS sources. We compare our results for local ULIRGs with higher redshift samples selected at 250 and 850 μm. These latter sources generally have cooler dust and/or redder 100-to-250 μm colours than our 60 μm-selected ULIRGs. We show that this difference may in part be the result of the sources being selected at different wavelengths rather than being a simple indication of rapid evolution in the properties of the population.

  5. Distributed Evaluation of Local Sensitivity Analysis (DELSA), with application to hydrologic models

    Science.gov (United States)

    Rakovec, O.; Hill, M. C.; Clark, M. P.; Weerts, A. H.; Teuling, A. J.; Uijlenhoet, R.

    2014-01-01

    This paper presents a hybrid local-global sensitivity analysis method termed the Distributed Evaluation of Local Sensitivity Analysis (DELSA), which is used here to identify important and unimportant parameters and evaluate how model parameter importance changes as parameter values change. DELSA uses derivative-based "local" methods to obtain the distribution of parameter sensitivity across the parameter space, which promotes consideration of sensitivity analysis results in the context of simulated dynamics. This work presents DELSA, discusses how it relates to existing methods, and uses two hydrologic test cases to compare its performance with the popular global, variance-based Sobol' method. The first test case is a simple nonlinear reservoir model with two parameters. The second test case involves five alternative "bucket-style" hydrologic models with up to 14 parameters applied to a medium-sized catchment (200 km2) in the Belgian Ardennes. Results show that in both examples, Sobol' and DELSA identify similar important and unimportant parameters, with DELSA enabling more detailed insight at much lower computational cost. For example, in the real-world problem the time delay in runoff is the most important parameter in all models, but DELSA shows that for about 20% of parameter sets it is not important at all and alternative mechanisms and parameters dominate. Moreover, the time delay was identified as important in regions producing poor model fits, whereas other parameters were identified as more important in regions of the parameter space producing better model fits. The ability to understand how parameter importance varies through parameter space is critical to inform decisions about, for example, additional data collection and model development. The ability to perform such analyses with modest computational requirements provides exciting opportunities to evaluate complicated models as well as many alternative models.

  6. Observability and Estimation of Distributed Space Systems via Local Information-Exchange Networks

    Science.gov (United States)

    Fathpour, Nanaz; Hadaegh, Fred Y.; Mesbahi, Mehran; Rahmani, Amirreza

    2011-01-01

    Spacecraft formation flying involves the coordination of states among multiple spacecraft through relative sensing, inter-spacecraft communication, and control. Most existing formation-flying estimation algorithms can only be supported via highly centralized, all-to-all, static relative sensing. New algorithms are proposed that are scalable, modular, and robust to variations in the topology and link characteristics of the formation exchange network. These distributed algorithms rely on a local information exchange network, relaxing the assumptions on existing algorithms. Distributed space systems rely on a signal transmission network among multiple spacecraft for their operation. Control and coordination among multiple spacecraft in a formation is facilitated via a network of relative sensing and interspacecraft communications. Guidance, navigation, and control rely on the sensing network. This network becomes more complex the more spacecraft are added, or as mission requirements become more complex. The observability of a formation state was observed by a set of local observations from a particular node in the formation. Formation observability can be parameterized in terms of the matrices appearing in the formation dynamics and observation matrices. An agreement protocol was used as a mechanism for observing formation states from local measurements. An agreement protocol is essentially an unforced dynamic system whose trajectory is governed by the interconnection geometry and initial condition of each node, with a goal of reaching a common value of interest. The observability of the interconnected system depends on the geometry of the network, as well as the position of the observer relative to the topology. For the first time, critical GN&C (guidance, navigation, and control estimation) subsystems are synthesized by bringing the contribution of the spacecraft information-exchange network to the forefront of algorithmic analysis and design. The result is a

  7. Predicting habitat suitability for rare plants at local spatial scales using a species distribution model.

    Science.gov (United States)

    Gogol-Prokurat, Melanie

    2011-01-01

    If species distribution models (SDMs) can rank habitat suitability at a local scale, they may be a valuable conservation planning tool for rare, patchily distributed species. This study assessed the ability of Maxent, an SDM reported to be appropriate for modeling rare species, to rank habitat suitability at a local scale for four edaphic endemic rare plants of gabbroic soils in El Dorado County, California, and examined the effects of grain size, spatial extent, and fine-grain environmental predictors on local-scale model accuracy. Models were developed using species occurrence data mapped on public lands and were evaluated using an independent data set of presence and absence locations on surrounding lands, mimicking a typical conservation-planning scenario that prioritizes potential habitat on unsurveyed lands surrounding known occurrences. Maxent produced models that were successful at discriminating between suitable and unsuitable habitat at the local scale for all four species, and predicted habitat suitability values were proportional to likelihood of occurrence or population abundance for three of four species. Unfortunately, models with the best discrimination (i.e., AUC) were not always the most useful for ranking habitat suitability. The use of independent test data showed metrics that were valuable for evaluating which variables and model choices (e.g., grain, extent) to use in guiding habitat prioritization for conservation of these species. A goodness-of-fit test was used to determine whether habitat suitability values ranked habitat suitability on a continuous scale. If they did not, a minimum acceptable error predicted area criterion was used to determine the threshold for classifying habitat as suitable or unsuitable. I found a trade-off between model extent and the use of fine-grain environmental variables: goodness of fit was improved at larger extents, and fine-grain environmental variables improved local-scale accuracy, but fine-grain variables

  8. Quasiparticle density of states, localization, and distributed disorder in the cuprate superconductors

    Science.gov (United States)

    Sulangi, Miguel Antonio; Zaanen, Jan

    2018-04-01

    We explore the effects of various kinds of random disorder on the quasiparticle density of states of two-dimensional d -wave superconductors using an exact real-space method, incorporating realistic details known about the cuprates. Random on-site energy and pointlike unitary impurity models are found to give rise to a vanishing DOS at the Fermi energy for narrow distributions and low concentrations, respectively, and lead to a finite, but suppressed, DOS at unrealistically large levels of disorder. Smooth disorder arising from impurities located away from the copper-oxide planes meanwhile gives rise to a finite DOS at realistic impurity concentrations. For the case of smooth disorder whose average potential is zero, a resonance is found at zero energy for the quasiparticle DOS at large impurity concentrations. We discuss the implications of these results on the computed low-temperature specific heat, the behavior of which we find is strongly affected by the amount of disorder present in the system. We also compute the localization length as a function of disorder strength for various types of disorder and find that intermediate- and high-energy states are quasiextended for low disorder, and that states near the Fermi energy are strongly localized and have a localization length that exhibits an unusual dependence on the amount of disorder. We comment on the origin of disorder in the cuprates and provide constraints on these based on known results from scanning tunneling spectroscopy and specific heat experiments.

  9. Neutron radiography characterization of an operating proton exchange membrane fuel cell with localized current distribution measurements

    International Nuclear Information System (INIS)

    Gagliardo, J.J.; Owejan, J.P.; Trabold, T.A.; Tighe, T.W.

    2009-01-01

    Neutron radiography has proven to be a powerful tool to study and understand the effects of liquid water in an operating fuel cell. In the present work, this experimental method is coupled with locally resolved current and ohmic resistance measurements, giving additional insight into water management and fuel cell performance under a variety of conditions. The effects of varying the inlet humidification level and the current density of the 50 cm 2 cell are studied by simultaneously monitoring electrochemical performance with a 10x10 matrix of current sensors, and liquid water volumes are measured using the National Institute of Standards and Technology (NIST) neutron imaging facility. A counter flow, straight channel proton exchange membrane (PEM) fuel cell is used to demonstrate localized performance loss corresponds to water-filled channels that impede gas transport to the catalyst layer, thereby creating an area that has low current density. Furthermore, certain operating conditions causing excess water accumulation in the channels can result in localized proton resistance increase, a result that can only be accurately observed with combined radiography and distributed electrochemical measurements.

  10. Global and local emission impact assessment of distributed cogeneration systems with partial-load models

    International Nuclear Information System (INIS)

    Mancarella, Pierluigi; Chicco, Gianfranco

    2009-01-01

    Small-scale distributed cogeneration technologies represent a key resource to increase generation efficiency and reduce greenhouse gas emissions with respect to conventional separate production means. However, the diffusion of distributed cogeneration within urban areas, where air quality standards are quite stringent, brings about environmental concerns on a local level. In addition, partial-load emission worsening is often overlooked, which could lead to biased evaluations of the energy system environmental performance. In this paper, a comprehensive emission assessment framework suitable for addressing distributed cogeneration systems is formulated. Local and global emission impact models are presented to identify upper and lower boundary values of the environmental pressure from pollutants that would be emitted from reference technologies, to be compared to the actual emissions from distributed cogeneration. This provides synthetic information on the relative environmental impact from small-scale CHP sources, useful for general indicative and non-site-specific studies. The emission models are formulated according to an electrical output-based emission factor approach, through which off-design operation and relevant performance are easily accounted for. In particular, in order to address the issues that could arise under off-design operation, an equivalent load model is incorporated within the proposed framework, by exploiting the duration curve of the cogenerator loading and the emissions associated to each loading level. In this way, it is possible to quantify the contribution to the emissions from cogeneration systems that might operate at partial loads for a significant portion of their operation time, as for instance in load-tracking applications. Suitability of the proposed methodology is discussed with respect to hazardous air pollutants such as NO x and CO, as well as to greenhouse gases such as CO 2 . Two case study applications based on the emission

  11. Spatial distribution of nanoparticles in PWR nanofluid coolant subjected to local nucleate boiling

    Energy Technology Data Exchange (ETDEWEB)

    Mirghaffari, Reza; Jahanfarnia, Gholamreza [Islamic Azad Univ., Tehran (Iran, Islamic Republic of). Dept. of Nuclear Engineering

    2016-12-15

    Nanofluids have shown to be promising as an alternative for a PWR reactor coolant or as a safety system coolant to cover the core in the event of a loss of coolant accident. The nanoparticles distribution and neutronic parameters are intensively affected by the local boiling of nanofluid coolant. The main goal of this study was the physical-mathematical modeling of the nanoparticles distribution in the nucleate boiling of nanofluids within the viscous sublayer. Nanoparticles concentration, especially near the heat transfer surfaces, plays a significant role in the enhancement of thermal conductivity of nanofluids and prediction of CHF, Hide Out and Return phenomena. By solving the equation of convection-diffusion for the liquid phase near the heating surface and the bulk stream, the effect of heat flux on the distribution of nanoparticles was studied. The steady state mass conservation equations for liquids, vapors and nanoparticles were written for the flow boiling within the viscous sublayer adjacent the fuel cladding surface. The derived differential equations were discretized by the finite difference method and were solved numerically. It was found out that by increasing the surface heat flux, the concentration of nanoparticles increased.

  12. The Hierarchical Distribution of the Young Stellar Clusters in Six Local Star-forming Galaxies

    Energy Technology Data Exchange (ETDEWEB)

    Grasha, K.; Calzetti, D. [Astronomy Department, University of Massachusetts, Amherst, MA 01003 (United States); Adamo, A.; Messa, M. [Dept. of Astronomy, The Oskar Klein Centre, Stockholm University, Stockholm (Sweden); Kim, H. [Gemini Observatory, La Serena (Chile); Elmegreen, B. G. [IBM Research Division, T.J. Watson Research Center, Yorktown Hts., NY (United States); Gouliermis, D. A. [Zentrum für Astronomie der Universität Heidelberg, Institut für Theoretische Astrophysik, Albert-Ueberle-Str. 2, D-69120 Heidelberg (Germany); Dale, D. A. [Dept. of Physics and Astronomy, University of Wyoming, Laramie, WY (United States); Fumagalli, M. [Institute for Computational Cosmology and Centre for Extragalactic Astronomy, Durham University, Durham (United Kingdom); Grebel, E. K.; Shabani, F. [Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, D-69120 Heidelberg (Germany); Johnson, K. E. [Dept. of Astronomy, University of Virginia, Charlottesville, VA (United States); Kahre, L. [Dept. of Astronomy, New Mexico State University, Las Cruces, NM (United States); Kennicutt, R. C. [Institute of Astronomy, University of Cambridge, Cambridge (United Kingdom); Pellerin, A. [Dept. of Physics and Astronomy, State University of New York at Geneseo, Geneseo NY (United States); Ryon, J. E.; Ubeda, L. [Space Telescope Science Institute, Baltimore, MD (United States); Smith, L. J. [European Space Agency/Space Telescope Science Institute, Baltimore, MD (United States); Thilker, D., E-mail: kgrasha@astro.umass.edu [Dept. of Physics and Astronomy, The Johns Hopkins University, Baltimore, MD (United States)

    2017-05-10

    We present a study of the hierarchical clustering of the young stellar clusters in six local (3–15 Mpc) star-forming galaxies using Hubble Space Telescope broadband WFC3/UVIS UV and optical images from the Treasury Program LEGUS (Legacy ExtraGalactic UV Survey). We identified 3685 likely clusters and associations, each visually classified by their morphology, and we use the angular two-point correlation function to study the clustering of these stellar systems. We find that the spatial distribution of the young clusters and associations are clustered with respect to each other, forming large, unbound hierarchical star-forming complexes that are in general very young. The strength of the clustering decreases with increasing age of the star clusters and stellar associations, becoming more homogeneously distributed after ∼40–60 Myr and on scales larger than a few hundred parsecs. In all galaxies, the associations exhibit a global behavior that is distinct and more strongly correlated from compact clusters. Thus, populations of clusters are more evolved than associations in terms of their spatial distribution, traveling significantly from their birth site within a few tens of Myr, whereas associations show evidence of disruption occurring very quickly after their formation. The clustering of the stellar systems resembles that of a turbulent interstellar medium that drives the star formation process, correlating the components in unbound star-forming complexes in a hierarchical manner, dispersing shortly after formation, suggestive of a single, continuous mode of star formation across all galaxies.

  13. The Hierarchical Distribution of the Young Stellar Clusters in Six Local Star-forming Galaxies

    Science.gov (United States)

    Grasha, K.; Calzetti, D.; Adamo, A.; Kim, H.; Elmegreen, B. G.; Gouliermis, D. A.; Dale, D. A.; Fumagalli, M.; Grebel, E. K.; Johnson, K. E.; Kahre, L.; Kennicutt, R. C.; Messa, M.; Pellerin, A.; Ryon, J. E.; Smith, L. J.; Shabani, F.; Thilker, D.; Ubeda, L.

    2017-05-01

    We present a study of the hierarchical clustering of the young stellar clusters in six local (3-15 Mpc) star-forming galaxies using Hubble Space Telescope broadband WFC3/UVIS UV and optical images from the Treasury Program LEGUS (Legacy ExtraGalactic UV Survey). We identified 3685 likely clusters and associations, each visually classified by their morphology, and we use the angular two-point correlation function to study the clustering of these stellar systems. We find that the spatial distribution of the young clusters and associations are clustered with respect to each other, forming large, unbound hierarchical star-forming complexes that are in general very young. The strength of the clustering decreases with increasing age of the star clusters and stellar associations, becoming more homogeneously distributed after ˜40-60 Myr and on scales larger than a few hundred parsecs. In all galaxies, the associations exhibit a global behavior that is distinct and more strongly correlated from compact clusters. Thus, populations of clusters are more evolved than associations in terms of their spatial distribution, traveling significantly from their birth site within a few tens of Myr, whereas associations show evidence of disruption occurring very quickly after their formation. The clustering of the stellar systems resembles that of a turbulent interstellar medium that drives the star formation process, correlating the components in unbound star-forming complexes in a hierarchical manner, dispersing shortly after formation, suggestive of a single, continuous mode of star formation across all galaxies.

  14. The Hierarchical Distribution of the Young Stellar Clusters in Six Local Star-forming Galaxies

    International Nuclear Information System (INIS)

    Grasha, K.; Calzetti, D.; Adamo, A.; Messa, M.; Kim, H.; Elmegreen, B. G.; Gouliermis, D. A.; Dale, D. A.; Fumagalli, M.; Grebel, E. K.; Shabani, F.; Johnson, K. E.; Kahre, L.; Kennicutt, R. C.; Pellerin, A.; Ryon, J. E.; Ubeda, L.; Smith, L. J.; Thilker, D.

    2017-01-01

    We present a study of the hierarchical clustering of the young stellar clusters in six local (3–15 Mpc) star-forming galaxies using Hubble Space Telescope broadband WFC3/UVIS UV and optical images from the Treasury Program LEGUS (Legacy ExtraGalactic UV Survey). We identified 3685 likely clusters and associations, each visually classified by their morphology, and we use the angular two-point correlation function to study the clustering of these stellar systems. We find that the spatial distribution of the young clusters and associations are clustered with respect to each other, forming large, unbound hierarchical star-forming complexes that are in general very young. The strength of the clustering decreases with increasing age of the star clusters and stellar associations, becoming more homogeneously distributed after ∼40–60 Myr and on scales larger than a few hundred parsecs. In all galaxies, the associations exhibit a global behavior that is distinct and more strongly correlated from compact clusters. Thus, populations of clusters are more evolved than associations in terms of their spatial distribution, traveling significantly from their birth site within a few tens of Myr, whereas associations show evidence of disruption occurring very quickly after their formation. The clustering of the stellar systems resembles that of a turbulent interstellar medium that drives the star formation process, correlating the components in unbound star-forming complexes in a hierarchical manner, dispersing shortly after formation, suggestive of a single, continuous mode of star formation across all galaxies.

  15. Experimental investigation of localized stress-induced leakage current distribution in gate dielectrics using array test circuit

    Science.gov (United States)

    Park, Hyeonwoo; Teramoto, Akinobu; Kuroda, Rihito; Suwa, Tomoyuki; Sugawa, Shigetoshi

    2018-04-01

    Localized stress-induced leakage current (SILC) has become a major problem in the reliability of flash memories. To reduce it, clarifying the SILC mechanism is important, and statistical measurement and analysis have to be carried out. In this study, we applied an array test circuit that can measure the SILC distribution of more than 80,000 nMOSFETs with various gate areas at a high speed (within 80 s) and a high accuracy (on the 10-17 A current order). The results clarified that the distributions of localized SILC in different gate areas follow a universal distribution assuming the same SILC defect density distribution per unit area, and the current of localized SILC defects does not scale down with the gate area. Moreover, the distribution of SILC defect density and its dependence on the oxide field for measurement (E OX-Measure) were experimentally determined for fabricated devices.

  16. Local knowledge, use pattern and geographical distribution of Moringa oleifera Lam. (Moringaceae) in Nigeria.

    Science.gov (United States)

    Popoola, Jacob O; Obembe, Olawole O

    2013-11-25

    All parts of Moringa oleifera are medicinally valuable with overlapping uses in treating myriads of ailments and diseases including body pains and weakness, fever, asthma, cough, blood pressure, arthritis, diabetes, epilepsy, wound, and skin infection. Moringa also has robust ability to challenge terminal diseases such as HIV/AIDs infections, chronic anemia, cancer, malaria and hemorrhage. The present study was to obtain ethnobotanical information on the use and local knowledge variation, geographical distribution, and to collect different landraces of Moringa oleifera from the different agro-ecological regions in Nigeria, for further studies. Ethnobotanical data were collected through face to face interviews, semi structured questionnaires and discussions with selected people who had knowledge about the plant. The fidelity level (FL %) and use value for different use categories of Moringa oleifera and its parts were estimated. The variation in ethnobotanical knowledge was evaluated by comparing the mean use value among ethnic, gender and age groups using sample T test. Garmi GPS was used to determine the locations (latitude and longitude) and height in different areas to assess the geographical spread of the species. Seven (7) categories of use (Food, medicine, fodder, fencing, firewood, gum and coagulant) were recorded for Moringa oleifera. Food and medicinal uses showed highest fidelity level while the leaves and the seeds were the plant parts most utilized for the same purposes. There were significant differences among the ethnic, gender and age groups regarding the ethno-botanical use value. The geographical distribution pattern shows that the Moringa oleifera is well distributed in all ecological zones of Nigeria, well adapted to the varied climatic conditions and gaining unprecedented awareness among the people. Though considered an introduced species, Moringa oleifera has found wide acceptance, recognition and usefulness among the various ethnicities in the

  17. On the sufficient conditions of the localization of the Fourier-Laplace series of distributions from liouville classes

    International Nuclear Information System (INIS)

    Ahmedov, Anvarjon A; Nurullah bin Rasedee, Ahmad Fadly; Rakhimov, Abdumalik

    2013-01-01

    In this work we investigate the localization principle of the Fourier-Laplace series of the distribution. Here we prove the sufficient conditions of the localization of the Riesz means of the spectral expansions of the Laplace-Beltrami operator on the unit sphere.

  18. Windows .NET Network Distributed Basic Local Alignment Search Toolkit (W.ND-BLAST

    Directory of Open Access Journals (Sweden)

    Oliver Melvin J

    2005-04-01

    Full Text Available Abstract Background BLAST is one of the most common and useful tools for Genetic Research. This paper describes a software application we have termed Windows .NET Distributed Basic Local Alignment Search Toolkit (W.ND-BLAST, which enhances the BLAST utility by improving usability, fault recovery, and scalability in a Windows desktop environment. Our goal was to develop an easy to use, fault tolerant, high-throughput BLAST solution that incorporates a comprehensive BLAST result viewer with curation and annotation functionality. Results W.ND-BLAST is a comprehensive Windows-based software toolkit that targets researchers, including those with minimal computer skills, and provides the ability increase the performance of BLAST by distributing BLAST queries to any number of Windows based machines across local area networks (LAN. W.ND-BLAST provides intuitive Graphic User Interfaces (GUI for BLAST database creation, BLAST execution, BLAST output evaluation and BLAST result exportation. This software also provides several layers of fault tolerance and fault recovery to prevent loss of data if nodes or master machines fail. This paper lays out the functionality of W.ND-BLAST. W.ND-BLAST displays close to 100% performance efficiency when distributing tasks to 12 remote computers of the same performance class. A high throughput BLAST job which took 662.68 minutes (11 hours on one average machine was completed in 44.97 minutes when distributed to 17 nodes, which included lower performance class machines. Finally, there is a comprehensive high-throughput BLAST Output Viewer (BOV and Annotation Engine components, which provides comprehensive exportation of BLAST hits to text files, annotated fasta files, tables, or association files. Conclusion W.ND-BLAST provides an interactive tool that allows scientists to easily utilizing their available computing resources for high throughput and comprehensive sequence analyses. The install package for W.ND-BLAST is

  19. STOMATOLOGIC ASPECTS IN THERAPY OF LOCALLY DISTRIBUTED CANCER OF ORAL CAVITY MUCUS

    Directory of Open Access Journals (Sweden)

    G. G. Matyakin

    2013-01-01

    Full Text Available Aim of the investigation: to improve prophylaxis of dental complications during the therapy in the patients with locally distributed cancer of oral cavity mucus.Materials. Results of sanation of oral cavity in 305 patients with cancer of oral and pharyngeal area are analyzed.Results. The best results are noted in the patients given surgical sanation before chemo-radial therapy. The most number of complications is observed when teeth were extracted after chemical therapy in the period of radial therapy at summary focal dose above 20 Gy as well as in the late periods after radial therapy.Conclusion. A complex of preventive measures with using haemostatic sponge with canamycin in such patients decreases the number of complications and the terms of healing of alveoli of extracted teeth.

  20. Research on fully distributed optical fiber sensing security system localization algorithm

    Science.gov (United States)

    Wu, Xu; Hou, Jiacheng; Liu, Kun; Liu, Tiegen

    2013-12-01

    A new fully distributed optical fiber sensing and location technology based on the Mach-Zehnder interferometers is studied. In this security system, a new climbing point locating algorithm based on short-time average zero-crossing rate is presented. By calculating the zero-crossing rates of the multiple grouped data separately, it not only utilizes the advantages of the frequency analysis method to determine the most effective data group more accurately, but also meets the requirement of the real-time monitoring system. Supplemented with short-term energy calculation group signal, the most effective data group can be quickly picked out. Finally, the accurate location of the climbing point can be effectively achieved through the cross-correlation localization algorithm. The experimental results show that the proposed algorithm can realize the accurate location of the climbing point and meanwhile the outside interference noise of the non-climbing behavior can be effectively filtered out.

  1. First-principles momentum-dependent local ansatz wavefunction and momentum distribution function bands of iron

    International Nuclear Information System (INIS)

    Kakehashi, Yoshiro; Chandra, Sumal

    2016-01-01

    We have developed a first-principles local ansatz wavefunction approach with momentum-dependent variational parameters on the basis of the tight-binding LDA+U Hamiltonian. The theory goes beyond the first-principles Gutzwiller approach and quantitatively describes correlated electron systems. Using the theory, we find that the momentum distribution function (MDF) bands of paramagnetic bcc Fe along high-symmetry lines show a large deviation from the Fermi–Dirac function for the d electrons with e g symmetry and yield the momentum-dependent mass enhancement factors. The calculated average mass enhancement m*/m = 1.65 is consistent with low-temperature specific heat data as well as recent angle-resolved photoemission spectroscopy (ARPES) data. (author)

  2. First-Principles Momentum-Dependent Local Ansatz Wavefunction and Momentum Distribution Function Bands of Iron

    Science.gov (United States)

    Kakehashi, Yoshiro; Chandra, Sumal

    2016-04-01

    We have developed a first-principles local ansatz wavefunction approach with momentum-dependent variational parameters on the basis of the tight-binding LDA+U Hamiltonian. The theory goes beyond the first-principles Gutzwiller approach and quantitatively describes correlated electron systems. Using the theory, we find that the momentum distribution function (MDF) bands of paramagnetic bcc Fe along high-symmetry lines show a large deviation from the Fermi-Dirac function for the d electrons with eg symmetry and yield the momentum-dependent mass enhancement factors. The calculated average mass enhancement m*/m = 1.65 is consistent with low-temperature specific heat data as well as recent angle-resolved photoemission spectroscopy (ARPES) data.

  3. Managing electricity procurement cost and risk by a local distribution company

    International Nuclear Information System (INIS)

    Chikeung Woo; Karimov, R.I.; Horowitz, I.

    2004-01-01

    A local electricity distribution company (LDC) can satisfy some of its future electricity requirements through self-generation and volatile spot markets, and the remainder through fixed-price forward contracts that will reduce its exposure to the inherent risk of spot-price volatility. A theoretical framework is developed for determining the forward-contract purchase that minimizes the LDCs expected procurement cost, subject to a cost-exposure constraint. The answers to the questions of ''What to buy?'' and ''How to buy?'' are illustrated using an example of a hypothetical LDC that is based on a municipal utility in Florida. It is shown that the LDCs procurement decision is consistent with least-cost procurement subject to a cost-exposure constraint, and that an internet-based multi-round auction can produce competitive price quotes for its desired forward purchase. (author)

  4. Managing electricity procurement cost and risk by a local distribution company

    International Nuclear Information System (INIS)

    Woo, C.-K.; Karimov, R.I.; Horowitz, Ira

    2004-01-01

    A local electricity distribution company (LDC) can satisfy some of its future electricity requirements through self-generation and volatile spot markets, and the remainder through fixed-price forward contracts that will reduce its exposure to the inherent risk of spot-price volatility. A theoretical framework is developed for determining the forward-contract purchase that minimizes the LDCs expected procurement cost, subject to a cost-exposure constraint. The answers to the questions of 'What to buy?' and 'How to buy?' are illustrated using an example of a hypothetical LDC that is based on a municipal utility in Florida. It is shown that the LDCs procurement decision is consistent with least-cost procurement subject to a cost-exposure constraint, and that an internet-based multi-round auction can produce competitive price quotes for its desired forward purchase

  5. Light-sheet fluorescence imaging to localize cardiac lineage and protein distribution

    Science.gov (United States)

    Ding, Yichen; Lee, Juhyun; Ma, Jianguo; Sung, Kevin; Yokota, Tomohiro; Singh, Neha; Dooraghi, Mojdeh; Abiri, Parinaz; Wang, Yibin; Kulkarni, Rajan P.; Nakano, Atsushi; Nguyen, Thao P.; Fei, Peng; Hsiai, Tzung K.

    2017-02-01

    Light-sheet fluorescence microscopy (LSFM) serves to advance developmental research and regenerative medicine. Coupled with the paralleled advances in fluorescence-friendly tissue clearing technique, our cardiac LSFM enables dual-sided illumination to rapidly uncover the architecture of murine hearts over 10 by 10 by 10 mm3 in volume; thereby allowing for localizing progenitor differentiation to the cardiomyocyte lineage and AAV9-mediated expression of exogenous transmembrane potassium channels with high contrast and resolution. Without the steps of stitching image columns, pivoting the light-sheet and sectioning the heart mechanically, we establish a holistic strategy for 3-dimentional reconstruction of the “digital murine heart” to assess aberrant cardiac structures as well as the spatial distribution of the cardiac lineages in neonates and ion-channels in adults.

  6. Accelerated Enveloping Distribution Sampling: Enabling Sampling of Multiple End States while Preserving Local Energy Minima.

    Science.gov (United States)

    Perthold, Jan Walther; Oostenbrink, Chris

    2018-05-17

    Enveloping distribution sampling (EDS) is an efficient approach to calculate multiple free-energy differences from a single molecular dynamics (MD) simulation. However, the construction of an appropriate reference-state Hamiltonian that samples all states efficiently is not straightforward. We propose a novel approach for the construction of the EDS reference-state Hamiltonian, related to a previously described procedure to smoothen energy landscapes. In contrast to previously suggested EDS approaches, our reference-state Hamiltonian preserves local energy minima of the combined end-states. Moreover, we propose an intuitive, robust and efficient parameter optimization scheme to tune EDS Hamiltonian parameters. We demonstrate the proposed method with established and novel test systems and conclude that our approach allows for the automated calculation of multiple free-energy differences from a single simulation. Accelerated EDS promises to be a robust and user-friendly method to compute free-energy differences based on solid statistical mechanics.

  7. The inner magnetosphere ion composition and local time distribution over a solar cycle

    Science.gov (United States)

    Kistler, L. M.; Mouikis, C. G.

    2016-03-01

    Using the Cluster/Composition and Distribution Function (CODIF) analyzer data set from 2001 to 2013, a full solar cycle, we determine the ion distributions for H+, He+, and O+ in the inner magnetosphere (L < 12) over the energy range 40 eV to 40 keV as a function magnetic local time, solar EUV (F10.7), and geomagnetic activity (Kp). Concentrating on L = 6-7 for comparison with previous studies at geosynchronous orbit, we determine both the average flux at 90° pitch angle and the pitch angle anisotropy as a function of energy and magnetic local time. We clearly see the minimum in the H+ spectrum that results from the competition between eastward and westward drifts. The feature is weaker in O+ and He+, leading to higher O+/H+ and He+/H+ ratios in the affected region, and also to a higher pitch angle anisotropy, both features expected from the long-term effects of charge exchange. We also determine how the nightside L = 6-7 densities and temperatures vary with geomagnetic activity (Kp) and solar EUV (F10.7). Consistent with other studies, we find that the O+ density and relative abundance increase significantly with both Kp and F10.7. He+ density increases with F10.7, but not significantly with Kp. The temperatures of all species decrease with increasing F10.7. The O+ and He+ densities increase from L = 12 to L ~ 3-4, both absolutely and relative to H+, and then drop off sharply. The results give a comprehensive view of the inner magnetosphere using a contiguous long-term data set that supports much of the earlier work from GEOS, ISEE, Active Magnetospheric Particle Tracer Explorers, and Polar from previous solar cycles.

  8. A new approach for beam hardening correction based on the local spectrum distributions

    International Nuclear Information System (INIS)

    Rasoulpour, Naser; Kamali-Asl, Alireza; Hemmati, Hamidreza

    2015-01-01

    Energy dependence of material absorption and polychromatic nature of x-ray beams in the Computed Tomography (CT) causes a phenomenon which called “beam hardening”. The purpose of this study is to provide a novel approach for Beam Hardening (BH) correction. This approach is based on the linear attenuation coefficients of Local Spectrum Distributions (LSDs) in the various depths of a phantom. The proposed method includes two steps. Firstly, the hardened spectra in various depths of the phantom (or LSDs) are estimated based on the Expectation Maximization (EM) algorithm for arbitrary thickness interval of known materials in the phantom. The performance of LSD estimation technique is evaluated by applying random Gaussian noise to transmission data. Then, the linear attenuation coefficients with regarding to the mean energy of LSDs are obtained. Secondly, a correction function based on the calculated attenuation coefficients is derived in order to correct polychromatic raw data. Since a correction function has been used for the conversion of the polychromatic data to the monochromatic data, the effect of BH in proposed reconstruction must be reduced in comparison with polychromatic reconstruction. The proposed approach has been assessed in the phantoms which involve less than two materials, but the correction function has been extended for using in the constructed phantoms with more than two materials. The relative mean energy difference in the LSDs estimations based on the noise-free transmission data was less than 1.5%. Also, it shows an acceptable value when a random Gaussian noise is applied to the transmission data. The amount of cupping artifact in the proposed reconstruction method has been effectively reduced and proposed reconstruction profile is uniform more than polychromatic reconstruction profile. - Highlights: • A novel Beam Hardening (BH) correction approach was described. • A new concept named Local Spectrum Distributions (LSDs) was used to BH

  9. A new approach for beam hardening correction based on the local spectrum distributions

    Energy Technology Data Exchange (ETDEWEB)

    Rasoulpour, Naser; Kamali-Asl, Alireza, E-mail: a_kamali@sbu.ac.ir; Hemmati, Hamidreza

    2015-09-11

    Energy dependence of material absorption and polychromatic nature of x-ray beams in the Computed Tomography (CT) causes a phenomenon which called “beam hardening”. The purpose of this study is to provide a novel approach for Beam Hardening (BH) correction. This approach is based on the linear attenuation coefficients of Local Spectrum Distributions (LSDs) in the various depths of a phantom. The proposed method includes two steps. Firstly, the hardened spectra in various depths of the phantom (or LSDs) are estimated based on the Expectation Maximization (EM) algorithm for arbitrary thickness interval of known materials in the phantom. The performance of LSD estimation technique is evaluated by applying random Gaussian noise to transmission data. Then, the linear attenuation coefficients with regarding to the mean energy of LSDs are obtained. Secondly, a correction function based on the calculated attenuation coefficients is derived in order to correct polychromatic raw data. Since a correction function has been used for the conversion of the polychromatic data to the monochromatic data, the effect of BH in proposed reconstruction must be reduced in comparison with polychromatic reconstruction. The proposed approach has been assessed in the phantoms which involve less than two materials, but the correction function has been extended for using in the constructed phantoms with more than two materials. The relative mean energy difference in the LSDs estimations based on the noise-free transmission data was less than 1.5%. Also, it shows an acceptable value when a random Gaussian noise is applied to the transmission data. The amount of cupping artifact in the proposed reconstruction method has been effectively reduced and proposed reconstruction profile is uniform more than polychromatic reconstruction profile. - Highlights: • A novel Beam Hardening (BH) correction approach was described. • A new concept named Local Spectrum Distributions (LSDs) was used to BH

  10. Ultrastructural changes in rabbits liver after irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Cieciura, L; Bartel, H; Orkisz, S

    1975-01-01

    Ultrastructural changes in hepatocytes observed 1 to 30 days after irradiation are presented. The dose absorbed was 550 rad (LD 33/30). Electron microscopy studies showed that early and more distinct changes were observed in mitochondria within 24 hours. Disintegration of endoplasmic reticulum and vacuolization of cytoplasm were seen on the 3rd day after irradiation. From the 9th day, the ultrastructural picture of hepatocytes became normal. In the liver in this period the increase in number of large hypertrophic macrophages was noted.

  11. STRUCTURE IN THE 3D GALAXY DISTRIBUTION. II. VOIDS AND WATERSHEDS OF LOCAL MAXIMA AND MINIMA

    International Nuclear Information System (INIS)

    Way, M. J.; Gazis, P. R.; Scargle, Jeffrey D.

    2015-01-01

    The major uncertainties in studies of the multi-scale structure of the universe arise not from observational errors but from the variety of legitimate definitions and detection methods for individual structures. To facilitate the study of these methodological dependencies, we have carried out 12 different analyses defining structures in various ways. This has been done in a purely geometrical way by utilizing the HOP algorithm as a unique parameter-free method of assigning groups of galaxies to local density maxima or minima. From three density estimation techniques (smoothing kernels, Bayesian blocks, and self-organizing maps) applied to three data sets (the Sloan Digital Sky Survey Data Release 7, the Millennium simulation, and randomly distributed points) we tabulate information that can be used to construct catalogs of structures connected to local density maxima and minima. We also introduce a void finder that utilizes a method to assemble Delaunay tetrahedra into connected structures and characterizes regions empty of galaxies in the source catalog

  12. Distributed and collaborative: Experiences of local leadership of a first-year experience program

    Directory of Open Access Journals (Sweden)

    Jo McKenzie

    2017-07-01

    Full Text Available Local level leadership of the first year experience (FYE is critical for engaging academic and professional staff in working collaboratively on a whole of institution focus on student transition and success. This paper describes ways in which local informal leadership is experienced at faculty level in an institutional FYE program, based on interviews with faculty coordinators and small grant recipients. Initial analysis using the distributed leadership tenets described by Jones, Hadgraft, Harvey, Lefoe, and Ryland (2014 revealed features that enabled success, such as collaborative communities, as well as faculty differences influenced by the strength of the external mandate for change in the FYE. More fine-grained analysis indicated further themes in engaging others, enabling and enacting the FYE program that fostered internal mandates for change: gaining buy-in; being opportunistic; making use of evidence of success and recognition; along with the need for collegial support for coordinators and self-perceptions of leadership being about making connections, collaboration, trust and expertise.

  13. Highly localized distributed Brillouin scattering response in a photonic integrated circuit

    Directory of Open Access Journals (Sweden)

    Atiyeh Zarifi

    2018-03-01

    Full Text Available The interaction of optical and acoustic waves via stimulated Brillouin scattering (SBS has recently reached on-chip platforms, which has opened new fields of applications ranging from integrated microwave photonics and on-chip narrow-linewidth lasers, to phonon-based optical delay and signal processing schemes. Since SBS is an effect that scales exponentially with interaction length, on-chip implementation on a short length scale is challenging, requiring carefully designed waveguides with optimized opto-acoustic overlap. In this work, we use the principle of Brillouin optical correlation domain analysis to locally measure the SBS spectrum with high spatial resolution of 800 μm and perform a distributed measurement of the Brillouin spectrum along a spiral waveguide in a photonic integrated circuit. This approach gives access to local opto-acoustic properties of the waveguides, including the Brillouin frequency shift and linewidth, essential information for the further development of high quality photonic-phononic waveguides for SBS applications.

  14. Local-Field Distribution of Two Dielectric Inclusions at Small Separation

    Science.gov (United States)

    Siu, Yuet-Lun; Yu, Kin-Wah

    2001-03-01

    When two dielectric inclusions approach to each other in a composite medium, significant mutual polarization effects must occur. These effects are multipolar in nature and are difficult to treat from first principles(J. D. Jackson, Classical Electrodynamics), 2nd edition, (Wiley, New York, 1975).. In this work, we employ the discrete-dipole theory(B. T. Draine and P. J. Flatau, J. Opt. Soc. Am. A 11) 1491 (1994). to account for the mutual polarization effects by dividing the inclusions into many small subparts. We begin the calculation at small inclusion sizes and large separation, where the point-dipole limit being valid, and proceed to larger inclusion sizes and small separation, for which the mutual polarization effect becomes important. Then, we apply the theory to determine the dipole moment of each subpart self-consistently. In this way, each dipole moment yields the local electric field, which in turn polarizes the neighboring dipoles. We also begin the calculation at small inclusion sizes and large separation, where the point-dipole limit being valid, and proceed to larger inclusion sizes and small separation. Our resluts indicate that convergence is achieved with moderate computational effects. The results produce valuable information about the local electric field distribution, which is relevant to optical absorption due to surface phonon-polaritons of ionic microcrystals.

  15. Pilot-multiplexed continuous-variable quantum key distribution with a real local oscillator

    Science.gov (United States)

    Wang, Tao; Huang, Peng; Zhou, Yingming; Liu, Weiqi; Zeng, Guihua

    2018-01-01

    We propose a pilot-multiplexed continuous-variable quantum key distribution (CVQKD) scheme based on a local local oscillator (LLO). Our scheme utilizes time-multiplexing and polarization-multiplexing techniques to dramatically isolate the quantum signal from the pilot, employs two heterodyne detectors to separately detect the signal and the pilot, and adopts a phase compensation method to almost eliminate the multifrequency phase jitter. In order to analyze the performance of our scheme, a general LLO noise model is constructed. Besides the phase noise and the modulation noise, the photon-leakage noise from the reference path and the quantization noise due to the analog-to-digital converter (ADC) are also considered, which are first analyzed in the LLO regime. Under such general noise model, our scheme has a higher key rate and longer secure distance compared with the preexisting LLO schemes. Moreover, we also conduct an experiment to verify our pilot-multiplexed scheme. Results show that it maintains a low level of the phase noise and is expected to obtain a 554-Kbps secure key rate within a 15-km distance under the finite-size effect.

  16. Myocardial distribution of I/sup 131/-labeled hexadecenoic acid in relation to the dog local coronary flow

    Energy Technology Data Exchange (ETDEWEB)

    Riche, F.; Busquet, G.; Pilichowski, P.; Wolf, J.E.; Mathieu, J.P.; Comet, M.; Pernin, C. (Centre Hospitalier Regional, 38 - Grenoble (France)); Vidal, M.; Vincens, M.; Godart, J. (Grenoble-1 Univ., 38 (France). Inst. des Sciences Nucleaires)

    1981-01-01

    20 anesthetized and thoracotomized dogs are studied. The local myocardial blood flow is measured with sup(99m)Tc human albumin microspheres. The intramyocardial distribution of the 16-I(131)-9-hexadecenoic acid in relation to local blood flow is studied in basal conditions (7 dogs), after experimental infarction (6 dogs) and postischemic reactive hyperhemia (7 dogs). We conclude that during basal condition, after infarction but not during reactive hyperhemia, the distribution of the labeled fatty acid reflect the local variations of blood flow.

  17. Seasonal and Local Characteristics of Lightning Outages of Power Distribution Lines in Hokuriku Area

    Science.gov (United States)

    Sugimoto, Hitoshi; Shimasaki, Katsuhiko

    The proportion of the lightning outages in all outages on Japanese 6.6kV distribution lines is high with approximately 20 percent, and then lightning protections are very important for supply reliability of 6.6kV lines. It is effective for the lightning performance to apply countermeasures in order of the area where a large number of the lightning outages occur. Winter lightning occurs in Hokuriku area, therefore it is also important to understand the seasonal characteristics of the lightning outages. In summer 70 percent of the lightning outages on distribution lines in Hokuriku area were due to sparkover, such as power wire breakings and failures of pole-mounted transformers. However, in winter almost half of lightning-damaged equipments were surge arrester failures. The number of the lightning outages per lightning strokes detected by the lightning location system (LLS) in winter was 4.4 times larger than that in summer. The authors have presumed the occurrence of lightning outages from lightning stroke density, 50% value of lightning current and installation rate of lightning protection equipments and overhead ground wire by multiple regression analysis. The presumed results suggest the local difference in the lightning outages.

  18. Gas source localization and gas distribution mapping with a micro-drone

    Energy Technology Data Exchange (ETDEWEB)

    Neumann, Patrick P.

    2013-07-01

    The objective of this Ph.D. thesis is the development and validation of a VTOL-based (Vertical Take Off and Landing) micro-drone for the measurement of gas concentrations, to locate gas emission sources, and to build gas distribution maps. Gas distribution mapping and localization of a static gas source are complex tasks due to the turbulent nature of gas transport under natural conditions and becomes even more challenging when airborne. This is especially so, when using a VTOL-based micro-drone that induces disturbances through its rotors, which heavily affects gas distribution. Besides the adaptation of a micro-drone for gas concentration measurements, a novel method for the determination of the wind vector in real-time is presented. The on-board sensors for the flight control of the micro-drone provide a basis for the wind vector calculation. Furthermore, robot operating software for controlling the micro-drone autonomously is developed and used to validate the algorithms developed within this Ph.D. thesis in simulations and real-world experiments. Three biologically inspired algorithms for locating gas sources are adapted and developed for use with the micro-drone: the surge-cast algorithm (a variant of the silkworm moth algorithm), the zigzag / dung beetle algorithm, and a newly developed algorithm called ''pseudo gradient algorithm''. The latter extracts from two spatially separated measuring positions the information necessary (concentration gradient and mean wind direction) to follow a gas plume to its emission source. The performance of the algorithms is evaluated in simulations and real-world experiments. The distance overhead and the gas source localization success rate are used as main performance criteria for comparing the algorithms. Next, a new method for gas source localization (GSL) based on a particle filter (PF) is presented. Each particle represents a weighted hypothesis of the gas source position. As a first step, the PF

  19. Gas source localization and gas distribution mapping with a micro-drone

    International Nuclear Information System (INIS)

    Neumann, Patrick P.

    2013-01-01

    The objective of this Ph.D. thesis is the development and validation of a VTOL-based (Vertical Take Off and Landing) micro-drone for the measurement of gas concentrations, to locate gas emission sources, and to build gas distribution maps. Gas distribution mapping and localization of a static gas source are complex tasks due to the turbulent nature of gas transport under natural conditions and becomes even more challenging when airborne. This is especially so, when using a VTOL-based micro-drone that induces disturbances through its rotors, which heavily affects gas distribution. Besides the adaptation of a micro-drone for gas concentration measurements, a novel method for the determination of the wind vector in real-time is presented. The on-board sensors for the flight control of the micro-drone provide a basis for the wind vector calculation. Furthermore, robot operating software for controlling the micro-drone autonomously is developed and used to validate the algorithms developed within this Ph.D. thesis in simulations and real-world experiments. Three biologically inspired algorithms for locating gas sources are adapted and developed for use with the micro-drone: the surge-cast algorithm (a variant of the silkworm moth algorithm), the zigzag / dung beetle algorithm, and a newly developed algorithm called ''pseudo gradient algorithm''. The latter extracts from two spatially separated measuring positions the information necessary (concentration gradient and mean wind direction) to follow a gas plume to its emission source. The performance of the algorithms is evaluated in simulations and real-world experiments. The distance overhead and the gas source localization success rate are used as main performance criteria for comparing the algorithms. Next, a new method for gas source localization (GSL) based on a particle filter (PF) is presented. Each particle represents a weighted hypothesis of the gas source position. As a first step, the PF-based GSL algorithm

  20. Gas source localization and gas distribution mapping with a micro-drone

    Energy Technology Data Exchange (ETDEWEB)

    Neumann, Patrick P.

    2013-07-01

    The objective of this Ph.D. thesis is the development and validation of a VTOL-based (Vertical Take Off and Landing) micro-drone for the measurement of gas concentrations, to locate gas emission sources, and to build gas distribution maps. Gas distribution mapping and localization of a static gas source are complex tasks due to the turbulent nature of gas transport under natural conditions and becomes even more challenging when airborne. This is especially so, when using a VTOL-based micro-drone that induces disturbances through its rotors, which heavily affects gas distribution. Besides the adaptation of a micro-drone for gas concentration measurements, a novel method for the determination of the wind vector in real-time is presented. The on-board sensors for the flight control of the micro-drone provide a basis for the wind vector calculation. Furthermore, robot operating software for controlling the micro-drone autonomously is developed and used to validate the algorithms developed within this Ph.D. thesis in simulations and real-world experiments. Three biologically inspired algorithms for locating gas sources are adapted and developed for use with the micro-drone: the surge-cast algorithm (a variant of the silkworm moth algorithm), the zigzag / dung beetle algorithm, and a newly developed algorithm called ''pseudo gradient algorithm''. The latter extracts from two spatially separated measuring positions the information necessary (concentration gradient and mean wind direction) to follow a gas plume to its emission source. The performance of the algorithms is evaluated in simulations and real-world experiments. The distance overhead and the gas source localization success rate are used as main performance criteria for comparing the algorithms. Next, a new method for gas source localization (GSL) based on a particle filter (PF) is presented. Each particle represents a weighted hypothesis of the gas source position. As a first step, the PF-based GSL algorithm

  1. Histochemical and ultrastructural studies on the calcareous corpuscles and eggs of Taenia taeniaeformis and Dipylidium caninum.

    Science.gov (United States)

    Khalifa, Refaat M A; Mazen, Nawal A M; Marawan, Aziza M A; Thabit, Hasnaa T M

    2011-08-01

    Calcareous corpuscles were noticed by several previous workers to be present in larval and adult cestodes without knowing their function. However, nothing was mentioned in the available literature about distribution of these corpuscles and their density, structure and composition in different parts of the body of different cestodes. Hence, in the present work, a comparative study of their distribution, density, histochemical and ultrastructural characters in different parts of the body was performed in Taenia taeniaeformis and Dipylidium caninum. Due to the presence of the eggs in their gravid segments, their histochemical and ultrastructural characteristics were also studied. It was found that the size, location and density of the calcareous bodies were different in different body parts of the same and the other cestode. Histochemically, the main component of these corpuscles was calcium; while other constituents as polysaccharides, lipids, protrins and mucopolysaccharides were found in their outer rim. Ultrastructurally, they were quite similar in the two studied cestodes and different stages of their development were exhibited. Histochemically, the eggs of both cestodes were similar in their contents. However, some ultrastructural differences have been demonstrated particularly in relation to the size and shape of the rods in the embryophore and the structures in between the embryophore and onchosphere.

  2. Atrial natriuretic peptide (ANP)-granules: ultrastructure ...

    African Journals Online (AJOL)

    ANP) are present in the four regions of the atrial-auricular complex (two atria and two auricles). ANP-immunoreactivity was detected in all granules from the four regions. Ultrastructurally, atrial myocytes show the presence of very electron dense ...

  3. EVIDENCE FOR A ∼300 MEGAPARSEC SCALE UNDER-DENSITY IN THE LOCAL GALAXY DISTRIBUTION

    Energy Technology Data Exchange (ETDEWEB)

    Keenan, R. C. [Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei 10617, Taiwan (China); Barger, A. J. [Department of Astronomy, University of Wisconsin-Madison, 475 North Charter Street, Madison, WI 53706 (United States); Cowie, L. L. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States)

    2013-09-20

    stellar mass density as a function of distance follows a similar trend. Assuming that luminous matter traces the underlying dark matter distribution, this implies that the local mass density of the universe may be lower than the global mass density on a scale and amplitude sufficient to introduce significant biases into the determination of basic cosmological observables. An under-density of roughly this scale and amplitude could resolve the apparent tension between direct measurements of the Hubble constant and those inferred by Planck.

  4. Local ISM 3D Distribution and Soft X-ray Background Inferences for Nearby Hot Gas

    Science.gov (United States)

    Puspitarini, L.; Lallement, R.; Snowden, Steven L.; Vergely, J.-L.; Snowden, S.

    2014-01-01

    Three-dimensional (3D) interstellar medium (ISM) maps can be used to locate not only interstellar (IS) clouds, but also IS bubbles between the clouds that are blown by stellar winds and supernovae, and are filled by hot gas. To demonstrate this, and to derive a clearer picture of the local ISM, we compare our recent 3D IS dust distribution maps to the ROSAT diffuse Xray background maps after removal of heliospheric emission. In the Galactic plane, there is a good correspondence between the locations and extents of the mapped nearby cavities and the soft (0.25 keV) background emission distribution, showing that most of these nearby cavities contribute to this soft X-ray emission. Assuming a constant dust to gas ratio and homogeneous 106 K hot gas filling the cavities, we modeled in a simple way the 0.25 keV surface brightness along the Galactic plane as seen from the Sun, taking into account the absorption by the mapped clouds. The data-model comparison favors the existence of hot gas in the solar neighborhood, the so-called Local Bubble (LB). The inferred mean pressure in the local cavities is found to be approx.9,400/cu cm K, in agreement with previous studies, providing a validation test for the method. On the other hand, the model overestimates the emission from the huge cavities located in the third quadrant. Using CaII absorption data, we show that the dust to CaII ratio is very small in those regions, implying the presence of a large quantity of lower temperature (non-X-ray emitting) ionized gas and as a consequence a reduction of the volume filled by hot gas, explaining at least part of the discrepancy. In the meridian plane, the two main brightness enhancements coincide well with the LB's most elongated parts and chimneys connecting the LB to the halo, but no particular nearby cavity is found towards the enhancement in the direction of the bright North Polar Spur (NPS) at high latitude. We searched in the 3D maps for the source regions of the higher energy

  5. local

    Directory of Open Access Journals (Sweden)

    Abílio Amiguinho

    2005-01-01

    Full Text Available The process of socio-educational territorialisation in rural contexts is the topic of this text. The theme corresponds to a challenge to address it having as main axis of discussion either the problem of social exclusion or that of local development. The reasons to locate the discussion in this last field of analysis are discussed in the first part of the text. Theoretical and political reasons are there articulated because the question is about projects whose intentions and practices call for the political both in the theoretical debate and in the choices that anticipate intervention. From research conducted for several years, I use contributions that aim at discuss and enlighten how school can be a potential locus of local development. Its identification and recognition as local institution (either because of those that work and live in it or because of those that act in the surrounding context are crucial steps to progressively constitute school as a partner for development. The promotion of the local values and roots, the reconstruction of socio-personal and local identities, the production of sociabilities and the equation and solution of shared problems were the dimensions of a socio-educative intervention, markedly globalising. This scenario, as it is argued, was also, intentionally, one of transformation and of deliberate change of school and of the administration of the educative territoires.

  6. Active damage localization for plate-like structures using wireless sensors and a distributed algorithm

    International Nuclear Information System (INIS)

    Liu, L; Yuan, F G

    2008-01-01

    Wireless structural health monitoring (SHM) systems have emerged as a promising technology for robust and cost-effective structural monitoring. However, the applications of wireless sensors on active diagnosis for structural health monitoring (SHM) have not been extensively investigated. Due to limited energy sources, battery-powered wireless sensors can only perform limited functions and are expected to operate at a low duty cycle. Conventional designs are not suitable for sensing high frequency signals, e.g. in the ultrasonic frequency range. More importantly, algorithms to detect structural damage with a vast amount of data usually require considerable processing and communication time and result in unaffordable power consumption for wireless sensors. In this study, an energy-efficient wireless sensor for supporting high frequency signals and a distributed damage localization algorithm for plate-like structures are proposed, discussed and validated to supplement recent advances made for active sensing-based SHM. First, the power consumption of a wireless sensor is discussed and identified. Then the design of a wireless sensor for active diagnosis using piezoelectric sensors is introduced. The newly developed wireless sensor utilizes an optimized combination of field programmable gate array (FPGA) and conventional microcontroller to address the tradeoff between power consumption and speed requirement. The proposed damage localization algorithm, based on an energy decay model, enables wireless sensors to be practically used in active diagnosis. The power consumption for data communication can be minimized while the power budget for data processing can still be affordable for a battery-powered wireless sensor. The Levenberg–Marquardt method is employed in a mains-powered sensor node or PC to locate damage. Experimental results and discussion on the improvement of power efficiency are given

  7. Local electricity market design for the coordination of distributed energy resources at district level

    NARCIS (Netherlands)

    Ampatzis, M.; Nguyen, P.H.; Kling, W.L.

    2014-01-01

    The increasing penetration of distributed energy resources at the distribution grid level creates concerns about their successful integration in the existing electric grid, designed for centralized generation by large power plants. Failure to the proper integration of distributed energy resources

  8. Improving electrical power systems reliability through locally controlled distributed curtailable load

    Science.gov (United States)

    Dehbozorgi, Mohammad Reza

    2000-10-01

    Improvements in power system reliability have always been of interest to both power companies and customers. Since there are no sizable electrical energy storage elements in electrical power systems, the generated power should match the load demand at any given time. Failure to meet this balance may cause severe system problems, including loss of generation and system blackouts. This thesis proposes a methodology which can respond to either loss of generation or loss of load. It is based on switching of electric water heaters using power system frequency as the controlling signal. The proposed methodology encounters, and the thesis has addressed, the following associated problems. The controller must be interfaced with the existing thermostat control. When necessary to switch on loads, the water in the tank should not be overheated. Rapid switching of blocks of load, or chattering, has been considered. The contributions of the thesis are: (A) A system has been proposed which makes a significant portion of the distributed loads connected to a power system to behave in a predetermined manner to improve the power system response during disturbances. (B) The action of the proposed system is transparent to the customers. (C) The thesis proposes a simple analysis for determining the amount of such loads which might be switched and relates this amount to the size of the disturbances which can occur in the utility. (D) The proposed system acts without any formal communication links, solely using the embedded information present system-wide. (E) The methodology of the thesis proposes switching of water heater loads based on a simple, localized frequency set-point controller. The thesis has identified the consequent problem of rapid switching of distributed loads, which is referred to as chattering. (F) Two approaches have been proposed to reduce chattering to tolerable levels. (G) A frequency controller has been designed and built according to the specifications required to

  9. Did a local distribution company procure prudently during the California electricity crisis?

    International Nuclear Information System (INIS)

    Woo, C.-K.; Lloyd, Debra; Clayton, William

    2006-01-01

    To manage cost risk, prudent procurement of electric power requires that some portion of a buyer's energy demand be met through long-term contracting. Under cost-of-service regulation or performance-based regulation, a local distribution company (LDC) should be allowed to fully recover all prudently incurred power procurement costs. However, the regulatory test of prudence is an ex post review with the threat of disallowance. This paper presents an economic analysis of procurement prudence involving a small LDC, Bear Valley Electric Service (BVES), which serves a resort area in Southern California. The key findings are: (a) high and volatile prices and rolling blackouts characterized the market environment faced by the owner of BVES, Southern California Water Company (SCWC), at its signing of a 5-year fixed price contract; (b) SCWC was a price-taker with no incentive to act imprudently; (c) the contract was obtained via a competitive bidding process; (d) the contract price was comparable to the benchmark price of contemporaneous contracts; (e) the fixed price contract was economic when compared to available alternatives; and (f) despite (a)-(e), a negotiated settlement with the state regulator and a large user resulted in substantial disallowance. The policy implication is that a regulator should approve a prudent procurement plan proposed by an LDC to remove the unreasonable risk of an ex post review. If the LDC strictly adheres to the plan, the resulting electricity purchases are per se prudent and should entitle the LDC to full cost recovery

  10. Local field distribution near corrugated interfaces: Green function formalism versus effective medium theory

    International Nuclear Information System (INIS)

    Choy, C.W.; Xiao, J.J.; Yu, K.W.

    2007-01-01

    The recent Green function formalism (GFF) has been used to study the local field distribution near a periodic interface separating two homogeneous media of different dielectric constants. In the GFF, the integral equations can be solved conveniently because of the existence of an analytic expression for the kernel (Greenian). However, due to a severe singularity in the Greenian, the formalism was formerly applied to compute the electric fields away from the interface region. In this work, we have succeeded in extending the GFF to compute the electric field inside the interface region by taking advantage of a sum rule. To our surprise, the strengths of the electric fields are quite similar in both media across the interface, despite of the large difference in dielectric constants. Moreover, we propose a simple effective medium approximation (EMA) to compute the electric field inside the interface region. We show that the EMA can indeed give an excellent description of the electric field, except near a surface plasmon resonance

  11. Integrated resource planning for local gas distribution companies: A critical review of regulatory policy issues

    International Nuclear Information System (INIS)

    Harunuzzaman, M.; Islam, M.

    1994-08-01

    According to the report, public utility commissions (PUCs) are increasingly adopting, or considering the adoption of integrated resource planning (IRP) for local gas distribution companies (LDCs). The Energy Policy Act of 1992 (EPAct) requires PUCs to consider IRP for gas LDCs. This study has two major objectives: (1) to help PUCs develop appropriate regulatory approaches with regard to IRP for gas LDCs; and (2) to help PUCs respond to the EPAct directive. The study finds that it is appropriate for PUCs to pursue energy efficiency within the traditional regulatory framework of minimizing private costs of energy production and delivery; and PUCs should play a limited role in addressing environmental externalities. The study also finds that in promoting energy efficiency, PUCs should pursue policies that are incentive-based, procompetitive, and sensitive to rate impacts. The study evaluates a number of traditional and nontraditional ratemaking mechanisms on the basis of cost minimization, energy efficiency, competitiveness, and other criteria. The mechanisms evaluated include direct recovery of DSM expenses, lost revenue adjustments for DSM options, revenue decoupling mechanisms, sharing of DSM cost savings, performance-based rate of return for DSM, provision of DSM as a separate service, deregulation of DSM service, price caps, and deregulation of the noncore gas market. The study concludes with general recommendations for regulatory approaches and ratemaking mechanisms that PUCs may wish to consider in advancing IRP objectives

  12. Radiofrequency Field Distribution Assessment in Indoor Areas Covered by Wireless Local Area Network

    Directory of Open Access Journals (Sweden)

    HELBET, R.

    2009-02-01

    Full Text Available Electromagnetic environment becomes day by day more congested. Radio communication systems in the short range are now part of everyday life, and there is a need to also assess the pollution level due to their emission if we take into account human health and protection. There is consistent scientific evidence that environmental electromagnetic field may cause undesirable biological effects or even health hazards. Present paper aims at giving a view on exposure level due to wireless local area networks (WLAN emission solely, as part of environmental radiofrequency pollution. Highly accurate measurements were made indoor by using a frequency-selective measurement system and identifying the correct settings for an error-minimum assessment. We focused on analysis of the electric flux density distribution inside a room, in the far field of the emitting antennas, in case of a single network communication channel. We analyze the influence the network configuration parameters have on the field level. Distance from the source and traffic rate are also important parameters that affect the exposure level. Our measurements indicate that in the immediate vicinity of the WLAN stations the average field may reach as much as 13% from the present accepted reference levels given in the human exposure standards.

  13. Local and landscape-scale biotic correlates of mistletoe distribution in Mediterranean pine forests

    Energy Technology Data Exchange (ETDEWEB)

    Roura-Pascual, N.; Brotons, L.; Garcia, D.; Zamora, R.; Caceres, M. de

    2012-11-01

    The study of the spatial patterns of species allows the examination of hypotheses on the most plausible ecological processes and factors determining their distribution. To investigate the determinants of parasite species on Mediterranean forests at regional scales, occurrence data of the European Misletoe (Viscum album) in Catalonia (NE Iberian Peninsula) were extracted from forest inventory data and combined with different types of explanatory variables by means of generalized linear mixed models. The presence of mistletoes in stands of Pinus halepensis seems to be determined by multiple factors (climatic conditions, and characteristics of the host tree and landscape structure) operating at different spatial scales, with the availability of orchards of Olea europaea in the surroundings playing a relevant role. These results suggest that host quality and landscape structure are important mediators of plant-plant and plant-animal interactions and, therefore, management of mistletoe populations should be conducted at both local (i.e. clearing of infected host trees) and landscape scales (e.g. controlling the availability of nutrient-rich food sources that attract bird dispersers). Research and management at landscape-scales are necessary to anticipate the negative consequence of land-use changes in Mediterranean forests. (Author) 38 refs.

  14. Effect of local automatic control rods on three-dimensional calculations of the power distribution in an RBMK

    International Nuclear Information System (INIS)

    Pogosbekyan, L.R.; Lysov, D.A.; Bronitskii, L.L.

    1993-01-01

    Numerical simulators and information systems that support nuclear reactor operators must have fast models to estimate how fuel reloads and control rod displacement affect neutron and power distributions in the core. The consequences of reloads and control rod displacement cannot be evaluated correctly without considering local automatic control-rod operations in maintaining the radial power distribution. Fast three-dimensional models to estimate the effects of reloads and displacement of the control and safety rods have already been examined. I.V. Zonov et al. used the following assumptions in their calculational model: (1) the full-scale problem could be reduced a three-dimensional fragment of a locally perturbed core, and (2) the boundary conditions of the fragment and its total power were constant. The last assumption considers approximately how local automatic control rods stabilize the radial power distribution, but three dimensional calculations with these rods are not considered. These assumptions were introduced to obtain high computational speed. I.L. Bronitskii et al. considered in more detail how moving the local automatic control rods affect the power dimensional in the three-dimensional fragment, because, with on-line monitoring of the reload process, information on control rod positions is periodically renewed, and the calculations are done in real time. This model to predict the three-dimensional power distribution to (1) do a preliminary reload analysis, and (2) prepare the core for reloading did not consider the effect of perturbations from the local automatic control rods. Here we examine a model of a stationary neutron distribution. On one hand it gives results in an acceptable computation time; on the other it is a full-scale three-dimensional model and considers how local automatic control rods affect both the radial and axial power distribution

  15. Explaining local-scale species distributions: relative contributions of spatial autocorrelation and landscape heterogeneity for an avian assemblage.

    Directory of Open Access Journals (Sweden)

    Brady J Mattsson

    Full Text Available Understanding interactions between mobile species distributions and landcover characteristics remains an outstanding challenge in ecology. Multiple factors could explain species distributions including endogenous evolutionary traits leading to conspecific clustering and endogenous habitat features that support life history requirements. Birds are a useful taxon for examining hypotheses about the relative importance of these factors among species in a community. We developed a hierarchical Bayes approach to model the relationships between bird species occupancy and local landcover variables accounting for spatial autocorrelation, species similarities, and partial observability. We fit alternative occupancy models to detections of 90 bird species observed during repeat visits to 316 point-counts forming a 400-m grid throughout the Patuxent Wildlife Research Refuge in Maryland, USA. Models with landcover variables performed significantly better than our autologistic and null models, supporting the hypothesis that local landcover heterogeneity is important as an exogenous driver for species distributions. Conspecific clustering alone was a comparatively poor descriptor of local community composition, but there was evidence for spatial autocorrelation in all species. Considerable uncertainty remains whether landcover combined with spatial autocorrelation is most parsimonious for describing bird species distributions at a local scale. Spatial structuring may be weaker at intermediate scales within which dispersal is less frequent, information flows are localized, and landcover types become spatially diversified and therefore exhibit little aggregation. Examining such hypotheses across species assemblages contributes to our understanding of community-level associations with conspecifics and landscape composition.

  16. Locality-Aware Task Scheduling and Data Distribution for OpenMP Programs on NUMA Systems and Manycore Processors

    Directory of Open Access Journals (Sweden)

    Ananya Muddukrishna

    2015-01-01

    Full Text Available Performance degradation due to nonuniform data access latencies has worsened on NUMA systems and can now be felt on-chip in manycore processors. Distributing data across NUMA nodes and manycore processor caches is necessary to reduce the impact of nonuniform latencies. However, techniques for distributing data are error-prone and fragile and require low-level architectural knowledge. Existing task scheduling policies favor quick load-balancing at the expense of locality and ignore NUMA node/manycore cache access latencies while scheduling. Locality-aware scheduling, in conjunction with or as a replacement for existing scheduling, is necessary to minimize NUMA effects and sustain performance. We present a data distribution and locality-aware scheduling technique for task-based OpenMP programs executing on NUMA systems and manycore processors. Our technique relieves the programmer from thinking of NUMA system/manycore processor architecture details by delegating data distribution to the runtime system and uses task data dependence information to guide the scheduling of OpenMP tasks to reduce data stall times. We demonstrate our technique on a four-socket AMD Opteron machine with eight NUMA nodes and on the TILEPro64 processor and identify that data distribution and locality-aware task scheduling improve performance up to 69% for scientific benchmarks compared to default policies and yet provide an architecture-oblivious approach for programmers.

  17. The changing food outlet distributions and local contextual factors in the United States.

    Science.gov (United States)

    Chen, Hsin-Jen; Wang, Youfa

    2014-01-16

    Little is known about the dynamics of the food outlet distributions associated with local contextual factors in the U.S. This study examines the changes in food stores/services at the 5-digit Zip Code Tabulated Area (ZCTA5) level in the U.S., and assesses contextual factors associated with the changes. Data from 27,878 ZCTA5s in the contiguous United States without an extreme change in the number of 6 types of food stores/services (supermarkets, small-size grocery stores, convenience stores, fresh/specialty food markets, carry-out restaurants, and full-service restaurants) were used. ZCTA5s' contextual factors were from the 2000 Census. Numbers of food stores/services were derived from the Census Business Pattern databases. Linear regression models assessed contextual factors' influences (racial/ethnic compositions, poverty rate, urbanization level, and foreign-born population%) on 1-year changes in food stores/services during 2000-2001, adjusted for population size, total business change, and census regions. Small-size grocery stores and fresh/specialty food markets increased more and convenience stores decreased more in Hispanic-predominant than other areas. Among supermarket-free places, new supermarkets were less likely to be introduced into black-predominant than white-predominant areas (odds ratio (OR) = 0.52, 95% CI = 0.30-0.92). However, among areas without the following type of store at baseline, supermarket (OR = 0.48 (0.33-0.70)), small-size grocery stores (OR = 1.32 (1.08-1.62)), and fresh/specialty food markets (OR = 0.70 (0.53-0.92)) were less likely to be introduced into areas of low foreign-born population than into areas of high foreign-born population. Higher poverty rate was associated with a greater decrease in supermarket, a less decrease in small-size grocery stores, and a less increase in carry-out restaurants (all p for trends restaurants than suburban areas. Local area characteristics affect 1-year changes in food

  18. Biological distribution of reactor produced 18F-FDG. Local experience

    International Nuclear Information System (INIS)

    Sierralta, M.P.; Massardo, T.; Gil, M.C.; Chandia, M.; Godoy, N.; Troncoso, F.; Jofre, M.J.

    2002-01-01

    Introduction: Quality control through an animal model that relates bio distribution of a substance is fundamental prior to using it in human beings. For the evaluation of myocardial viability after recent myocardial infarction, the use of reactor produced 18F-FDG (a radiotracer usually obtained in cyclotron) is proposed, production of wish had never been attempted in our country. The aim of the study was to compare the specific activities found in the different tissues after the injection of this reactor produced radiopharmaceutical with those obtained by others authors with cyclotron 18F-FDG. Material WISTAR female white mice, men weight 25,28 +/- 1,09 g (23,8-26,9 range) in standard support conditions was used. 1,22 MBq (33 mCi) of 18F-FDG were injected in a lateral tail vein. Previously anaesthetised with Chloroform, the animals were sacrificed by jugular section at 5, 30 and 60 minutes intervals post injection. Blood and organs were removed (liver, lungs, heart, brain, urine plus bladder, kidneys, femur, muscle and quivers), placed in vials, then weighed, and finally taken to a Gamma Packard Minaxi γ Auto-gamma 5000 serie counter to obtain the counts per minute (cpm) (previously the empty vials were weighed too). At same time, STANDARDS (STD) (3 dilutions) cpm and BACKGROUND (BKG) cpm were collected. We calculate 1) mean BKG cpm, 2) mean STD cpm, who then were corrected by decay factor and dilution, and 3) each one of the tissues cpm, that then were corrected by decay factor, divided by the corresponding dilution cpm and multiplied by 100 to obtain the Injected Activity % (IA%). Finally, the IA% was divided by the tissue weight and get the Specific Activity (SA). Mean and standard deviation for each tissue at the 3 intervals were calculated. Results: The uptake distribution at 30 and 60 minutes were similar between reactor and cyclotron produced 18F-FDG, with significant bigger SA in heart and brain respect of the rest organs. There were significant

  19. Biological distribution of reactor produced 18F-FDG. Local experience

    Energy Technology Data Exchange (ETDEWEB)

    Sierralta, M P [University of Chile Clinical Hospital Nuclear Medicine Centre, Santiago (Chile); Military Hospital Nuclear Medicine Department, Santiago (Chile); Massardo, T [University of Chile Clinical Hospital Nuclear Medicine Centre, Santiago (Chile); Gil, M C [CGM Nuclear, Santiago (Chile); Chandia, M; Godoy, N; Troncoso, F [CCHEN, CEN La Reina, Santiago (Chile); Jofre, M J [Military Hospital Nuclear Medicine Department, Santiago (Chile)

    2002-09-01

    Introduction: Quality control through an animal model that relates bio distribution of a substance is fundamental prior to using it in human beings. For the evaluation of myocardial viability after recent myocardial infarction, the use of reactor produced 18F-FDG (a radiotracer usually obtained in cyclotron) is proposed, production of wish had never been attempted in our country. The aim of the study was to compare the specific activities found in the different tissues after the injection of this reactor produced radiopharmaceutical with those obtained by others authors with cyclotron 18F-FDG. Material WISTAR female white mice, men weight 25,28 +/- 1,09 g (23,8-26,9 range) in standard support conditions was used. 1,22 MBq (33 mCi) of 18F-FDG were injected in a lateral tail vein. Previously anaesthetised with Chloroform, the animals were sacrificed by jugular section at 5, 30 and 60 minutes intervals post injection. Blood and organs were removed (liver, lungs, heart, brain, urine plus bladder, kidneys, femur, muscle and quivers), placed in vials, then weighed, and finally taken to a Gamma Packard Minaxi {gamma} Auto-gamma 5000 serie counter to obtain the counts per minute (cpm) (previously the empty vials were weighed too). At same time, STANDARDS (STD) (3 dilutions) cpm and BACKGROUND (BKG) cpm were collected. We calculate 1) mean BKG cpm, 2) mean STD cpm, who then were corrected by decay factor and dilution, and 3) each one of the tissues cpm, that then were corrected by decay factor, divided by the corresponding dilution cpm and multiplied by 100 to obtain the Injected Activity % (IA%). Finally, the IA% was divided by the tissue weight and get the Specific Activity (SA). Mean and standard deviation for each tissue at the 3 intervals were calculated. Results: The uptake distribution at 30 and 60 minutes were similar between reactor and cyclotron produced 18F-FDG, with significant bigger SA in heart and brain respect of the rest organs. There were significant

  20. The Magnetic Local Time Distribution of Energetic Electrons in the Radiation Belt Region

    Science.gov (United States)

    Allison, H. J.

    2017-12-01

    Using fourteen years of electron flux data from the National Oceanic and Atmospheric Administration Polar Operational Environmental Satellites (POES), a statistical study of the magnetic local time (MLT) distribution of the electron population is performed across a range of activity levels, defined by AE, AE*, Kp, solar wind velocity (Vsw), and VswBz. Three electron energies (>30, >100, and >300 keV) are considered. Dawn-dusk flux asymmetries larger than order of magnitude were observed for >30 and >100 keV electrons. For >300 keV electrons, dawn-dusk asymmetries were primarily due to a decrease in the average dusk-side flux beyond L* ˜ 4.5 that arose with increasing activity. For the >30 keV population, substorm injections enhance the dawn-side flux, which may not reach the dusk-side as the electrons can be on open drift paths and lost to the magnetopause. The asymmetries in the >300 keV population are attributed to the combination of magnetopause shadowing and >300 keV electron injections by large electric fields. We suggest that 3D radiation belt models could set the minimum energy boundary (Emin) to 30 keV or above at L* ˜6 during periods of low activity. However, for more moderate conditions, Emin should be larger than 100 keV and, for very extreme activities, ˜300 keV. Our observations show the extent that in-situ electron flux readings may vary during active periods due to the MLT of the satellite and highlight the importance of 4D radiation belt models to fully understand radiation belt processes.

  1. Local multipoint distribution system (LDMS) versus free-space optical (FSO) networks

    Science.gov (United States)

    Willebrand, Heinz A.; Clark, Gerald R.; Willson, Bryan; Andreu von Euw, Christian G.; Roy, Joe; Mayhew, Laurel M.

    2001-11-01

    This paper compares two emerging broadband access methodologies, Free Space Optics (FSO) and Local Multipoint Distribution System (LMDS) and the atmospheric propagation characteristics of each when exposed to a dynamically changing channel. The comparison focuses on bandwidth, availability, and distance requirements for the new broadband market and how LMDS and FSO can be used to meet these requirements. Possible network topologies and their associated costs are examined. This comparison takes into account the total cost of deployment, including equipment costs, installation fees, access fees, and spectrum licensing fees. LMDS and FSO are compared on speed of deployment, scalability, aggregate bandwidth, and bandwidth per customer. Present and projected capabilities of each technology are considered for their suitability in different locations in the network, from the Wide Area Network (WAN), to the Metropolitan Area Network (MAN), all the way to Last Mile Access. There is a discussion on the relative performance of LMDS and FSO, focusing on the different factors that can affect link availability. Since network design is a large factor in assuring overall reliability, the flexibility of each technology with regard to network design is compared. LMDS and FSO are both line of sight, space-propagated technologies, and as such, they are both susceptible to path impediments and atmospheric attenuation, dispersion, scattering, and absorption. LMDS and FSO are affected very differently by different meteorological phenomena. Problematic atmospheric conditions are, specifically scintillation, rainfall, and fog, are examined. In addition to a discussion of these conditions, various techniques for minimizing atmospheric and environmental effects are investigated. The paper concludes with a summary of findings and recommendations for a number of broadband wireless applications.

  2. Local time distribution of the SSC-associated HF-Doppler frequency shifts

    International Nuclear Information System (INIS)

    Kikuchi, T.; Sugiuchi, H.; Ishimine, T.

    1985-01-01

    The HF-Doppler frequency shift observed at the storm's sudden commencement is composed of a frequency increase (+) and decrease (-), and classified into four types, SCF(+ -), SCF(- +), SCF(+) and SCF(-). Since the latter two types are special cases of the former two types, two different kinds of electrical field exist in the F region and cause the ExB drift motion of plasma. HUANG (1976) interpreted the frequency increase of SCF(+ -) as due to the westward induction electric field proportional to delta H/ delta t and the succeeding frequency decrease due to the eastward conduction electric field which produces ionospheric currents responsible for the magnetic increase on the ground. In spite of his success in interpreting the SCF(+ -), some other interpretations are needed for the explanation of the whole set of SCF's, particularly SCF(- +). Local time distributions of the SCF's are derived from 41 SCF's which are observed on the HF standard signal (JJY) as received in Okinawa (path length =1600 km) and Kokubunji (60 km). It is shown that the SCF(+ -) appears mainly during the day, whereas the SCF(- +) is observed during the night. The results indicate that the preliminary frequency shift (+) of SCF(+ -) and (-) of SCF(- +) is caused by a westward electric field in the dayside hemisphere, while by an eastward electric field in the nightside hemisphere. The main frequency shift (-) of SCF(+ -) and (+) of SCF(- +) is caused by the reversed electric field. Consequently, the preliminary frequency shift is caused by the dusk-to-dawn electric field, while the main frequency shift by the dawn-to-dusk electric field

  3. Local time distribution of the SSC-associated HF-Doppler frequency shifts

    Science.gov (United States)

    Kikuchi, T.; Sugiuchi, H.; Ishimine, T.

    1985-01-01

    The HF-Doppler frequency shift observed at the storm's sudden commencement is composed of a frequency increase (+) and decrease (-), and classified into four types, SCF(+ -), SCF(- +), SCF(+) and SCF(-). Since the latter two types are special cases of the former two types, two different kinds of electrical field exist in the F region and cause the ExB drift motion of plasma. HUANG (1976) interpreted the frequency increase of SCF(+ -) as due to the westward induction electric field proportional to delta H/ delta t and the succeeding frequency decrease due to the eastward conduction electric field which produces ionospheric currents responsible for the magnetic increase on the ground. In spite of his success in interpreting the SCF(+ -), some other interpretations are needed for the explanation of the whole set of SCF's, particularly SCF(- +). Local time distributions of the SCF's are derived from 41 SCF's which are observed on the HF standard signal (JJY) as received in Okinawa (path length =1600 km) and Kokubunji (60 km). It is shown that the SCF(+ -) appears mainly during the day, whereas the SCF(- +) is observed during the night. The results indicate that the preliminary frequency shift (+) of SCF(+ -) and (-) of SCF(- +) is caused by a westward electric field in the dayside hemisphere, while by an eastward electric field in the nightside hemisphere. The main frequency shift (-) of SCF(+ -) and (+) of SCF(- +) is caused by the reversed electric field. Consequently, the preliminary frequency shift is caused by the dusk-to-dawn electric field, while the main frequency shift by the dawn-to-dusk electric field.

  4. Assessing water resources in Azerbaijan using a local distributed model forced and constrained with global data

    Science.gov (United States)

    Bouaziz, Laurène; Hegnauer, Mark; Schellekens, Jaap; Sperna Weiland, Frederiek; ten Velden, Corine

    2017-04-01

    In many countries, data is scarce, incomplete and often not easily shared. In these cases, global satellite and reanalysis data provide an alternative to assess water resources. To assess water resources in Azerbaijan, a completely distributed and physically based hydrological wflow-sbm model was set-up for the entire Kura basin. We used SRTM elevation data, a locally available river map and one from OpenStreetMap to derive the drainage direction network at the model resolution of approximately 1x1 km. OpenStreetMap data was also used to derive the fraction of paved area per cell to account for the reduced infiltration capacity (c.f. Schellekens et al. 2014). We used the results of a global study to derive root zone capacity based on climate data (Wang-Erlandsson et al., 2016). To account for the variation in vegetation cover over the year, monthly averages of Leaf Area Index, based on MODIS data, were used. For the soil-related parameters, we used global estimates as provided by Dai et al. (2013). This enabled the rapid derivation of a first estimate of parameter values for our hydrological model. Digitized local meteorological observations were scarce and available only for limited time period. Therefore several sources of global meteorological data were evaluated: (1) EU-WATCH global precipitation, temperature and derived potential evaporation for the period 1958-2001 (Harding et al., 2011), (2) WFDEI precipitation, temperature and derived potential evaporation for the period 1979-2014 (by Weedon et al., 2014), (3) MSWEP precipitation (Beck et al., 2016) and (4) local precipitation data from more than 200 stations in the Kura basin were available from the NOAA website for a period up to 1991. The latter, together with data archives from Azerbaijan, were used as a benchmark to evaluate the global precipitation datasets for the overlapping period 1958-1991. By comparing the datasets, we found that monthly mean precipitation of EU-WATCH and WFDEI coincided well

  5. Nucleolar ultrastructure in bovine nuclear transfer embryos

    DEFF Research Database (Denmark)

    Kanka, J; Smith, S D; Soloy, E

    1999-01-01

    in nuclear morphology as a transformation of the nucleolus precursor body into a functional rRNA synthesising nucleolus with a characteristic ultrastructure. We examined nucleolar ultrastructure in bovine in vitro produced (control) embryos and in nuclear transfer embryos reconstructed from a MII phase...... at 1 hr after fusion and, by 3 hr after fusion, it was restored again. At this time, the reticulated fibrillo-granular nucleolus had an almost round shape. The nucleolar precursor body seen in the two-cell stage nuclear transfer embryos consisted of intermingled filamentous components and secondary...... time intervals after fusion. In the two-cell stage nuclear transfer embryo, the originally reticulated nucleolus of the donor blastomere had changed into a typical nucleolar precursor body consisting of a homogeneous fibrillar structure. A primary vacuole appeared in the four-cell stage nuclear...

  6. Ultrastructural and Histochemical Characterization of the Zebra Mussel Adhesive Apparatus

    Science.gov (United States)

    Farsad, Nikrooz

    Since their accidental introduction into the Great Lakes in mid- to late-1980s, the freshwater zebra mussels, Dreissena polymorpha, have colonized most lakes and waterways across eastern North America. Their rapid spread is partly attributed to their ability to tenaciously attach to hard substrates via an adhesive apparatus called the byssus, resulting in serious environmental and economic impacts. A detailed ultrastructural study of the byssus revealed a 10 nm adhesive layer at the attachment interface. Distributions of the main adhesive amino acid, 3,4-dihydroxyphenylalanine (DOPA), and its oxidizing (cross-linking) enzyme, catechol oxidase, were determined histochemically. It was found that, upon aging, DOPA levels remained high in the portion of the byssus closest to the interface, consistent with an adhesive role. In contrast, reduced levels of DOPA corresponded well with high levels of catechol oxidase in the load-bearing component of the byssus, presumably forming cross-links and increasing the cohesive strength.

  7. Autoradiographic and ultrastructural studies on the human fibro-atheromatous plaque

    Energy Technology Data Exchange (ETDEWEB)

    Villaschi, S.; Spagnoli, L.G. (Universita degli Studi, Rome (Italy). Istituto di Anatomia ed Istologia Patologica)

    1983-07-01

    Foam cells, either myogenic or macrophagic, are commonly detected in experimental and human fibro-atheromatous plaques. Their role in human atherosclerosis is not yet understood. This paper reports on a preliminary autoradiographic study combined with ultrastructural observations in the human fibro-atheromatous plaque. Most of the autoradiographic silver grains appeared on foam cells and monocytelike cells, thus suggesting a local proliferation of these cells.

  8. Autoradiographic and ultrastructural studies on the human fibro-atheromatous plaque

    International Nuclear Information System (INIS)

    Villaschi, Sergio; Spagnoli, L.G.

    1983-01-01

    Foam cells, either myogenic or macrophagic, are commonly detected in experimental and human fibro-atheromatous plaques. Their role in human atherosclerosis is not yet understood. This paper reports on a preliminary autoradiographic study combined with ultrastructural observations in the human fibro-atheromatous plaque. Most of the autoradiographic silver grains appeared on foam cells and monocytelike cells, thus suggesting a local proliferation of these cells. (author)

  9. Effect of Local Strain Distribution of Cold-Rolled Alloy 690 on Primary Water Stress Corrosion Crack Growth Behavior

    Directory of Open Access Journals (Sweden)

    Kim S.-W.

    2017-06-01

    Full Text Available This work aims to study the stress corrosion crack growth behavior of cold-rolled Alloy 690 in the primary water of a pressurized water reactor. Compared with Alloy 600, which shows typical intergranular cracking along high angle grain boundaries, the cold-rolled Alloy 690, with its heterogeneous microstructure, revealed an abnormal crack growth behavior in mixed mode, that is, in transgranular cracking near a banded region, and in intergranular cracking in a matrix region. From local strain distribution analysis based on local mis-orientation, measured along the crack path using the electron back scattered diffraction method, it was suggested that the abnormal behavior was attributable to a heterogeneity of local strain distribution. In the cold-rolled Alloy 690, the stress corrosion crack grew through a highly strained area formed by a prior cold-rolling process in a direction perpendicular to the maximum principal stress applied during a subsequent stress corrosion cracking test.

  10. Histology and ultrastructure of the integumental chromatophores in tokay gecko (Gekko gecko) (Linnaeus, 1758) skin

    OpenAIRE

    Szyd?owski, Pawe?; Madej, Jan Pawe?; Mazurkiewicz-Kania, Marta

    2017-01-01

    This paper describes the relationship between the arrangement of dermal chromatophores in tokay gecko (Gekko gecko) skin and the formation of wild-type colouration, with emphasis on the ultrastructure of chromatophores. The samples of the tokay gecko skin were collected from wild-type colouration adult specimens. Morphology and distribution of chromatophores was determined by using light microscopy and transmission electron microscopy. The present study revealed that orange/red coloured skin ...

  11. The changing food outlet distributions and local contextual factors in the United States

    Science.gov (United States)

    2014-01-01

    Background Little is known about the dynamics of the food outlet distributions associated with local contextual factors in the U.S. This study examines the changes in food stores/services at the 5-digit Zip Code Tabulated Area (ZCTA5) level in the U.S., and assesses contextual factors associated with the changes. Methods Data from 27,878 ZCTA5s in the contiguous United States without an extreme change in the number of 6 types of food stores/services (supermarkets, small-size grocery stores, convenience stores, fresh/specialty food markets, carry-out restaurants, and full-service restaurants) were used. ZCTA5s’ contextual factors were from the 2000 Census. Numbers of food stores/services were derived from the Census Business Pattern databases. Linear regression models assessed contextual factors’ influences (racial/ethnic compositions, poverty rate, urbanization level, and foreign-born population%) on 1-year changes in food stores/services during 2000–2001, adjusted for population size, total business change, and census regions. Results Small-size grocery stores and fresh/specialty food markets increased more and convenience stores decreased more in Hispanic-predominant than other areas. Among supermarket-free places, new supermarkets were less likely to be introduced into black-predominant than white-predominant areas (odds ratio (OR) = 0.52, 95% CI = 0.30-0.92). However, among areas without the following type of store at baseline, supermarket (OR = 0.48 (0.33-0.70)), small-size grocery stores (OR = 1.32 (1.08-1.62)), and fresh/specialty food markets (OR = 0.70 (0.53-0.92)) were less likely to be introduced into areas of low foreign-born population than into areas of high foreign-born population. Higher poverty rate was associated with a greater decrease in supermarket, a less decrease in small-size grocery stores, and a less increase in carry-out restaurants (all p for trends <0.001). Urban areas experienced more increases in full

  12. Localizing Fracture Hydromechanical Response using Fiber Optic Distributed Acoustic Sensing in a Fractured Bedock Aquifer

    Science.gov (United States)

    Ciervo, C.; Becker, M.; Cole, M. C.; Coleman, T.; Mondanos, M.

    2017-12-01

    Measuring fracture mechanical behavior in response to changes in fluid pressure is critical for understanding flow through petroleum reservoirs, predicting hydrothermal responses in geothermal fields, and monitoring geologic carbon sequestration injection. Distributed acoustic sensing (DAS) is new, but commercially available fiber optic technology that offers a novel approach to characterize fractured bedrock systems. DAS was originally designed to measure the amplitude, frequency, and phase of an acoustic wave, and is therefore capable of detecting strains at exceedingly small scales. Though normally used to measure frequencies in the Hz to kHz range, we adapted DAS to measure fracture displacements in response to periodic hydraulic pulses in the mHz frequency range. A field experiment was conducted in a fractured bedrock aquifer to test the ability of DAS to measure fracture mechanical response to oscillatory well tests. Fiber optic cable was deployed in a well, and coupled to the borehole wall using a flexible impermeable liner designed with an air coupled transducer to measure fluid pressure at the target fracture zone. Two types of cable were tested, a loose tube and tight buffered, to determine the effects of cable construction. Both strain and pressure were measured across the known fracture zone hydraulically connected to a well 30 m away. The companion well was subjected to alternating pumping and injection with periods between 2 and 18 minutes. Raw DAS data were collected as strain rate measured every 0.25 m along the fiber with a gauge length of 10 m, at a sampling rate of 1 kHz. Strain rate was converted to strain by integrating with respect to time. DAS measured periodic strains of less than 1 nm/m in response to periodic injection and pumping at the companion well. Strain was observed by DAS only at the depth of the hydraulically connected fracture zone. Thus, the magnitude and response of the strain could be both localized with depth and measured

  13. Distributed illumination control with local sensing and actuation in networked lighting systems

    NARCIS (Netherlands)

    Caicedo Fernandez, D.R.; Pandharipande, A.

    2013-01-01

    We consider the problem of illumination control in a networked lighting system wherein luminaires have local sensing and actuation capabilities. Each luminaire (i) consists of a light emitting diode (LED) based light source dimmable by a local controller, (ii) is actuated based on sensing

  14. Changes in root gravitropism, ultrastructure, and calcium balance of pea root statocytes induced by A23187

    Science.gov (United States)

    Belyavskaya, N.

    The role for calcium in the regulation of a wide variety of cellular events in plants is well known. Calcium signaling has been implicated in plant gravitropism. A carboxylic acid antibiotic A23187 (calcimycin) has been widely used in biological studies since it can translocate calcium across membranes. Seedlings of Pisum sativum L. cv. Uladovsky germinated in a vertically oriented cylinder of moist filter paper soaked in water during 4.5 day had been treated with 10-5 M A23187 for 12 hr. Tips of primary roots of control and A23187-treated pea seedlings were fixed for electron microscopy and electron cytochemistry. Experiments with Pisum sativum 5- day seedlings placed horizontally for 4 h after treatment with 10 μM A23187 during 12 h found that the graviresponsiveness of their primary roots was lost completely (91 % of roots) or inhibited (24 +/- 6° in comparison with 88 +/- 8° in control). At ultrastructural level, there were observed distribution of amyloplasts around the nucleus, remarkable lengthening of statocytes, advanced vacuolization, changes in dictyosome structure, ER fragmentation, cell wall thinning in A23187-treated statocytes. Cytochemical study has indicated that statocytes exposed to calcimycin have contained a number of Ca-pyroantimonate granules detected Ca 2 + ions in organelles and hyaloplasm (unlike the control ones). The deposits were mainly associated with the plasma membrane. Among organelles, mitochondria were notable for their ability to accumulate Ca 2 +. In amyloplasts, a fine precipitate was predominately located in their stroma and envelope lumens. In cell walls, deposits of the reaction product were observed along the periphery and in the median zone. Localization of electron-dense granules of lead phosphate, which indicated Ca 2 +- ATPase activities in pea statocytes exposed to A23187, was generally consistent with that in untreated roots. Apart from plasma membrane, chromatin, and nucleolus components, the cytochemical reaction

  15. Research on suitable heating conditions during local PWHT. Pt. 1. Influence of heating conditions on temperature distribution

    International Nuclear Information System (INIS)

    Tanaka, Jinkichi; Horii, Yukihiko; Sato, Masanobu; Murakawa, Hidekazu; Wang Jianhua

    1999-01-01

    To improve weld joint properties a heat treatment so called post weld heat treatment (PWHT) is often implemented for steel weldment. Generally, the PWHT is conducted in a furnace at a factory. But in site welds such as the girth joint of pipe, a local PWHT is applied using electric heater and so on. In the local PWHT steep temperature gradient occurs depending on the heating condition and it leads to rise of the thermal stress in addition to the welding residual stress. However, heating condition is not always defined the same in some standards. Therefore, suitable heat conditions for the local PWHT were studied supposing the power plant and so on experimentally and theoretically. Temperature distribution and thermal strains under different heating conditions were measured during the local PWHT using carbon steel pipes of 340 mm in diameter and 53 mm in wall thickness. The temperature gradient, thermal strain were also analyzed using Finite Element Method (FEM) as axis-symmetric model. Further, the influences of pipe size and heat transfer coefficient on the temperature distribution were analyzed and suitable heating source widths for various pipe sizes were proposed from the viewpoint of temperature distribution. (orig.)

  16. Dutch gas distribution grid goes green: decision support tool for local biogas utilization

    NARCIS (Netherlands)

    Weidenaar, Teade; Hoekstra, Sipke; Wolters, Mannes

    2011-01-01

    A Decision Support Tool (DST) has been developed that will aid Distribution Service Operators (DSOs) in their decision making process on which investments to make in the gas distribution grid in order to facilitate the use of biogas. The DST considers both the conversion of biogas to electricity as

  17. The Reviewing of Distributed Power Sources Impact on Fallout’s Localization in 22 kV Network

    Directory of Open Access Journals (Sweden)

    Peter Bracinik

    2008-01-01

    Full Text Available The aim of this paper is to point out some facts that will occur by fault localization in 22 kV networks after the implementation of distributed power sources, especially wind power plants. This paper describes possible connection of these sources into power system in regard to their rated output. It also presents short theoretical background for short circuit calculation in 22 kV network. Then several examples explaining how the point of wind power plant connection can influence network’s operation during short-circuits and consequential fault’s localization are described in the second part of this paper

  18. Local authorities faced with electricity market liberalization. The role of cities in electricity production and distribution in the Swiss Confederation

    International Nuclear Information System (INIS)

    Storelli, St.

    2008-01-01

    In Switzerland, cities are highly involved in producing and - mainly - distributing electrical power. To those cities, defining what universal service and public interest service are seems essential, when faced with the opening energy markets. Such services can be guaranteed through concession contracts granted to companies conducting business on the city's territory It is the interest of regional distribution companies (one thousand in Switzerland...) to free themselves of local political requirements that could impair their growth. This new independence, combined with the good community service guarantee, should help those companies continue to contribute to the economic and lasting growth of the regions they have always served. (author)

  19. Using distributed processing on a local area network to increase available computing power

    International Nuclear Information System (INIS)

    Capps, K.S.; Sherry, K.J.

    1996-01-01

    The migration from central computers to desktop computers distributed the total computing horsepower of a system over many different machines. A typical engineering office may have several networked desktop computers that are sometimes idle, especially after work hours and when people are absent. Users would benefit if applications were able to use these networked computers collectively. This paper describes a method of distributing the workload of an application on one desktop system to otherwise idle systems on the network. The authors present this discussion from a developer's viewpoint, because the developer must modify an application before the user can realize any benefit of distributed computing on available systems

  20. Method of determining local distribution of water or aqueous solutions penetrated into plastics

    International Nuclear Information System (INIS)

    Krejci, M.; Joks, Z.

    1983-01-01

    Penetrating water is labelled with tritium and the distribution is autoradiographically monitored. The discovery consists in that the plastic with the penetrating water or aqueous solution is cooled with liquid nitrogen and under the stream of liquid nitrogen the plastic is cut and exposed on the autoradiographic film in the freezer at temperatures from -15 to -30 degC. The autoradiogram will show the distribution of water in the whole area of the section. The described method may be used to detect water distribution also in filled plastics. (J.P.)

  1. Ultrastructural findings in Hashimoto's thyroiditis and focal lymphocytic thyroiditis with reference to giant cell formation.

    Science.gov (United States)

    Knecht, H; Hedinger, C E

    1982-09-01

    Ultrastructural findings in two cases of Hashimoto's disease and two cases of focal lymphocytic thyroiditis are reported. Stimulated thyrocytes, oncocytes and degenerating thyrocytes were observed in all cases. Multinucleated thyrocytes and epithelial pseudogiant cells were identified in Hashimoto's disease only. Infiltrating lymphocytes, plasma cells, monocytes and macrophages were present in all cases. The ultrastructure of germinal centres was similar to that seen in lymphatic organs. Giant cells of both intra- and extrafollicular localization were seen in Hashimoto's disease. Most of the giant cells were macrophage-derived. Two different ways of giant cell formation were identified: besides the familiar dissolution of plasma membranes of adjacent macrophages, another mechanism of fusion was observed. At sites of contact, peculiar membrane structures were developed and disintegration of plasma membranes occurred in parts adjacent to these structures. These are not identical to desmosomes and are different from Langerhans' granules. They probably represent special organelles for the initiation of cellular fusion.

  2. Histoenzymatic and ultrastructural changes in the hepatocytes of gamma-irradiated rabbits

    Energy Technology Data Exchange (ETDEWEB)

    Cieciura, L; Bartel, H; Kaczmarek, B; Harazna, J; Orkisz, S [Wojskowa Akademia Medyczna, Lodz (Poland)

    1976-01-01

    Ultrastructural changes and intracellular enzyme activities in the hepatocytes were studied in rabbits irradiated with 550 rads of gamma rays at 1, 3, 6, 9, 15 and 30 days after irradiation. Swelling and marked rarefaction of the mitochondrial matrix observed on the first day were followed by gradual condensation of the matrix between the 6th and 9th day. This state was accompanied by marked reduction in the succinate dehydrogenase activity, which gradually returned to the normal by the 30th day of observation. In the hyaloplasm, the most intense changes developed between the third and sixth day and were manifested by clearing of the cytoplasm and marked fragmentation of the endoplasmic membranes, with concurrent negligible decline of the lactate dehydrogenase activity and unchanged glucose-6-phosphate activity. In the Golgi apparatus, vacuolization of the cytoplasm and fragmentation of smooth membranes were most pronounced on the 6th day and were correlated with a weakened and diffuse reaction for thiamine pyrophospatase. The alkaline phosphatase activity was irregularly distributed in the lobule. The activities of lysosomal hydrolases, i.e. acid phosphatase, ..beta..-glucuronidase and non-specific esterase, had various localizations within the lobules. The strongest deviations from the normal and of longest duration (up to 9 days) were seen in the Browicz-Kupffer cells. Complex studies on the same material conducted concurrently with the use of different methods showed that radiation damages structure and function in unequal degrees. Moreover, within the same organ the cellular response to ionizing radiation varies according to the character, localization and functional state of the cells. Deviations from the normal state occur between the first and ninth days, most of the structural and functional elements show signs of return to the normal about the 15th day after irradiation.

  3. Ultrastructural findings in noncompaction prevail with neuromuscular disorders.

    Science.gov (United States)

    Finsterer, Josef; Stöllberger, Claudia

    2013-01-01

    Little is known about the ultrastructural abnormalities of left ventricular hypertrabeculation/noncompaction (LVHT). This literature review aimed to summarize and discuss ultrastructural abnormalities described in LVHT so far. The literature search was conducted via MEDLINE using the search terms 'non-compaction', 'noncompaction', 'left ventricular hypertrabeculation', 'spongy myocardium' in combination with the terms 'ultra-structural', or 'electron microscopy'. Altogether, 11 studies reporting ultrastructural investigations of LVHT were retrieved. In these 11 studies, data on 13 patients with LVHT were presented. Ultrastructural abnormalities found in these study patients were generally nonspecific and included an increase in the number of mitochondria (n = 3), abnormally shaped mitochondria (n = 2), distorted cristae (n = 3), sarcomeric derangement (n = 3), immature cardiomyocytes (n = 1), lipid-like inclusions (n = 1), enlarged interstitial spaces (n = 1), increased interstitial collagen (n = 1), or increased glycogen (n = 1). The morphological abnormalities were most prominent in patients with a neuromuscular disorder like Barth syndrome or mitochondrial myopathy. Only in few patients with LVHT, ultrastructural investigations have been performed so far. Ultrastructural abnormalities in LVHT are nonspecific and most prominent in patients with a neuromuscular disorder. There is a strong need to carry out thorough ultrastructural investigations of LVHT to contribute to the understanding of this still unexplained myocardial abnormality.

  4. Inter-relationships of haplosporidians deduced from ultrastructural studies

    NARCIS (Netherlands)

    Hine, P.M.; Carnegie, R.B.; Burreson, E.M.; Engelsma, M.Y.

    2009-01-01

    We reviewed papers reporting haplosporidian ultrastructure to compare inter-relationships based on ultrastructure with those based on molecular data, to identify features that may be important in haplosporidian taxonomy, and to consider parasite taxonomy in relation to host taxonomy. There were

  5. Distributed Bayesian Computation and Self-Organized Learning in Sheets of Spiking Neurons with Local Lateral Inhibition.

    Directory of Open Access Journals (Sweden)

    Johannes Bill

    Full Text Available During the last decade, Bayesian probability theory has emerged as a framework in cognitive science and neuroscience for describing perception, reasoning and learning of mammals. However, our understanding of how probabilistic computations could be organized in the brain, and how the observed connectivity structure of cortical microcircuits supports these calculations, is rudimentary at best. In this study, we investigate statistical inference and self-organized learning in a spatially extended spiking network model, that accommodates both local competitive and large-scale associative aspects of neural information processing, under a unified Bayesian account. Specifically, we show how the spiking dynamics of a recurrent network with lateral excitation and local inhibition in response to distributed spiking input, can be understood as sampling from a variational posterior distribution of a well-defined implicit probabilistic model. This interpretation further permits a rigorous analytical treatment of experience-dependent plasticity on the network level. Using machine learning theory, we derive update rules for neuron and synapse parameters which equate with Hebbian synaptic and homeostatic intrinsic plasticity rules in a neural implementation. In computer simulations, we demonstrate that the interplay of these plasticity rules leads to the emergence of probabilistic local experts that form distributed assemblies of similarly tuned cells communicating through lateral excitatory connections. The resulting sparse distributed spike code of a well-adapted network carries compressed information on salient input features combined with prior experience on correlations among them. Our theory predicts that the emergence of such efficient representations benefits from network architectures in which the range of local inhibition matches the spatial extent of pyramidal cells that share common afferent input.

  6. Distributed Bayesian Computation and Self-Organized Learning in Sheets of Spiking Neurons with Local Lateral Inhibition

    Science.gov (United States)

    Bill, Johannes; Buesing, Lars; Habenschuss, Stefan; Nessler, Bernhard; Maass, Wolfgang; Legenstein, Robert

    2015-01-01

    During the last decade, Bayesian probability theory has emerged as a framework in cognitive science and neuroscience for describing perception, reasoning and learning of mammals. However, our understanding of how probabilistic computations could be organized in the brain, and how the observed connectivity structure of cortical microcircuits supports these calculations, is rudimentary at best. In this study, we investigate statistical inference and self-organized learning in a spatially extended spiking network model, that accommodates both local competitive and large-scale associative aspects of neural information processing, under a unified Bayesian account. Specifically, we show how the spiking dynamics of a recurrent network with lateral excitation and local inhibition in response to distributed spiking input, can be understood as sampling from a variational posterior distribution of a well-defined implicit probabilistic model. This interpretation further permits a rigorous analytical treatment of experience-dependent plasticity on the network level. Using machine learning theory, we derive update rules for neuron and synapse parameters which equate with Hebbian synaptic and homeostatic intrinsic plasticity rules in a neural implementation. In computer simulations, we demonstrate that the interplay of these plasticity rules leads to the emergence of probabilistic local experts that form distributed assemblies of similarly tuned cells communicating through lateral excitatory connections. The resulting sparse distributed spike code of a well-adapted network carries compressed information on salient input features combined with prior experience on correlations among them. Our theory predicts that the emergence of such efficient representations benefits from network architectures in which the range of local inhibition matches the spatial extent of pyramidal cells that share common afferent input. PMID:26284370

  7. A trade-off between local and distributed information processing associated with remote episodic versus semantic memory.

    Science.gov (United States)

    Heisz, Jennifer J; Vakorin, Vasily; Ross, Bernhard; Levine, Brian; McIntosh, Anthony R

    2014-01-01

    Episodic memory and semantic memory produce very different subjective experiences yet rely on overlapping networks of brain regions for processing. Traditional approaches for characterizing functional brain networks emphasize static states of function and thus are blind to the dynamic information processing within and across brain regions. This study used information theoretic measures of entropy to quantify changes in the complexity of the brain's response as measured by magnetoencephalography while participants listened to audio recordings describing past personal episodic and general semantic events. Personal episodic recordings evoked richer subjective mnemonic experiences and more complex brain responses than general semantic recordings. Critically, we observed a trade-off between the relative contribution of local versus distributed entropy, such that personal episodic recordings produced relatively more local entropy whereas general semantic recordings produced relatively more distributed entropy. Changes in the relative contributions of local and distributed entropy to the total complexity of the system provides a potential mechanism that allows the same network of brain regions to represent cognitive information as either specific episodes or more general semantic knowledge.

  8. Experimental and numerical study of impact of voltage fluctuate, flicker and power factor wave electric generator to local distribution

    Science.gov (United States)

    Hadi, Nik Azran Ab; Rashid, Wan Norhisyam Abd; Hashim, Nik Mohd Zarifie; Mohamad, Najmiah Radiah; Kadmin, Ahmad Fauzan

    2017-10-01

    Electricity is the most powerful energy source in the world. Engineer and technologist combined and cooperated to invent a new low-cost technology and free carbon emission where the carbon emission issue is a major concern now due to global warming. Renewable energy sources such as hydro, wind and wave are becoming widespread to reduce the carbon emissions, on the other hand, this effort needs several novel methods, techniques and technologies compared to coal-based power. Power quality of renewable sources needs in depth research and endless study to improve renewable energy technologies. The aim of this project is to investigate the impact of renewable electric generator on its local distribution system. The power farm was designed to connect to the local distribution system and it will be investigated and analyzed to make sure that energy which is supplied to customer is clean. The MATLAB tools are used to simulate the overall analysis. At the end of the project, a summary of identifying various voltage fluctuates data sources is presented in terms of voltage flicker. A suggestion of the analysis impact of wave power generation on its local distribution is also presented for the development of wave generator farms.

  9. Local Scour : Influence of an exponential eddy viscosity distribution on the longitudial flow velocity

    NARCIS (Netherlands)

    Hoffmans, G.J.C.M.

    1988-01-01

    The general purpose of this research project is to model mathematically the local scour downstream of a structure (2-D). The model has to simulate the development of the scour as a function of the time. Basically two models are necessary namely a flow model and a morphological model. The latter

  10. Distributed Transmitter Localization by Power Difference of Arrival (PDOA) on a Network of GNU Radio Sensors

    Science.gov (United States)

    2015-02-03

    requiring the least hardware investment is to localize by received signal strength [1, 4, 5]. Because our intended scenario of low-complexity...MHz were taken with a spectrum analyzer program on the USRP and a range finder was used to measure the distance between the emitter and sensor

  11. Aerodynamic design of horizontal axis wind turbine with innovative local linearization of chord and twist distributions

    DEFF Research Database (Denmark)

    Tahani, Mojtaba; Kavari, Ghazale; Masdari, Mehran

    2017-01-01

    This study is aimed to aerodynamically design a 1 mega-Watt horizontal axis wind turbine in order to obtain the maximum power coefficient by linearizing the chord and twist distributions. A new linearization method has been used for chord and twist distributions by crossing tangent line through...... the geometry of the blades determines the power generated by rotor, designing the blade is a very important issue. Herein, calculations are done for different types of airfoil families namely Risø-A1-21, Risø-A1-18, S809, S814 and Du 93-W-210. Hence, the effect of selecting different airfoil families is also...

  12. Ultrastructural observations of target-organs of the crayfish Orconectes limosus exposed to metallic pollutants: application to uranium

    International Nuclear Information System (INIS)

    Grasset, G.; Simon, O.; Floriani, M.

    2004-01-01

    Using electron microscopy associated with energy dispersive X-ray microanalysis (EDAXTEM), ultrastructure and elemental analysis in subcellular micro-localization can bring understanding to both metabolic cycle of a metallic pollutant and its potential effects at the subcellular scale. The approach consists in comparing both structures and micro-localization in various tissues/organs ultrathin sections (70-140 nm thickness) obtained from control organisms (i.e. not exposed to a given metal) and exposed organisms. However, the observations of ultrastructural effects of metal exposure involved robust comparison to reference subcellular and cellular organization. Consequently, preliminary developments presented in this poster have been performed from the non-contaminated freshwater crayfish Orconectes limosus (adult at inter-moult state). Studies of ultrastructural images and elemental composition of subcellular mineral deposits were carried out on target organs of uranium accumulation such as the digestive gland, the gills, the intestine and the antennal gland, organs participating in the detoxification, primary accumulation and depuration mechanisms. Observations indicated cell-specific architecture (identification of main organelles, frequency, length of cells), the range of natural variation of the cell organisation between individuals and identification of cellular types. Information will allow then to focus on these identified specific organization after metallic exposure. These ultrastructural observations performed on reference organisms constitute necessarily a first set of data for the cellular metallic effects analysis. (author)

  13. Ultrastructural Morphology of Sperm from Human Globozoospermia

    Directory of Open Access Journals (Sweden)

    Giuseppe Ricci

    2015-01-01

    Full Text Available Globozoospermia is a rare disorder characterized by the presence of sperm with round head, lacking acrosome. Coiling tail around the nucleus has been reported since early human studies, but no specific significance has conferred it. By contrast, studies on animal models suggest that coiling tail around the nucleus could represent a crucial step of defective spermatogenesis, resulting in round-headed sperm. No observations, so far, support the transfer of this hypothesis to human globozoospermia. The purpose of this work was to compare ultrastructural morphology of human and mouse model globozoospermic sperm. Sperm have been investigated by using scanning and transmission electron microscopy. The images that we obtained show significant similarities to those described in GOPC knockout mice, an animal model of globozoospermia. By using this model as reference, we were able to identify the probable steps of the tail coiling process in human globozoospermia. Although we have no evidence that there is the same pathophysiology in man and knocked-out mouse, the similarities between these ultrastructural observations in human and those in the experimental model are very suggestive. This is the first demonstration of the existence of relevant morphological homologies between the tail coiling in animal model and human globozoospermia.

  14. Ultrastructure, biology, and phylogenetic relationships of kinorhyncha.

    Science.gov (United States)

    Neuhaus, Birger; Higgins, Robert P

    2002-07-01

    The article summarizes current knowledge mainly about the (functional) morphology and ultrastructure, but also about the biology, development, and evolution of the Kinorhyncha. The Kinorhyncha are microscopic, bilaterally symmetrical, exclusively free-living, benthic, marine animals and ecologically part of the meiofauna. They occur throughout the world from the intertidal to the deep sea, generally in sediments but sometimes associated with plants or other animals. From adult stages 141 species are known, but 38 species have been described from juvenile stages. The trunk is arranged into 11 segments as evidenced by cuticular plates, sensory spots, setae or spines, nervous system, musculature, and subcuticular glands. The ultrastructure of several organ systems and the postembryonic development are known for very few species. Almost no data are available about the embryology and only a single gene has been sequenced for a single species. The phylogenetic relationships within Kinorhyncha are unresolved. Priapulida, Loricifera, and Kinorhyncha are grouped together as Scalidophora, but arguments are found for every possible sistergroup relationship within this taxon. The recently published Ecdysozoa hypothesis suggests a closer relationship of the Scalidophora, Nematoda, Nematomorpha, Tardigrada, Onychophora, and Arthropoda.

  15. Climate change and plant distribution: local models predict high-elevation persistence

    DEFF Research Database (Denmark)

    Randin, Christophe F.; Engler, Robin; Normand, Signe

    2009-01-01

    Mountain ecosystems will likely be affected by global warming during the 21st century, with substantial biodiversity loss predicted by species distribution models (SDMs). Depending on the geographic extent, elevation range, and spatial resolution of data used in making these models, different rates...

  16. Enhanced Local Grid Voltage Support Method for High Penetration of Distributed Generators

    DEFF Research Database (Denmark)

    Demirok, Erhan; Sera, Dezso; Rodriguez, Pedro

    2011-01-01

    Grid voltage rise and thermal loading of network components are the most remarkable barriers to allow high number of distributed generator (DG) connections on the medium voltage (MV) and low voltage (LV) electricity networks. The other barriers such as grid power quality (harmonics, voltage...

  17. Enhancing guideline-based decision support with distributed computation through local mobile application

    NARCIS (Netherlands)

    Shalom, Erez; Shahar, Yuval; Goldstein, Ayelet; Ariel, Elior; Quaglini, Silvana; Sacchi, Lucia; Fung, L.S.N.; Jones, Valerie M.; Broens, T.H.F.; García-Sáez, Gema; Hernando, Elena

    2014-01-01

    We introduce the need for a distributed guideline-based decision support (DSS) process, describe its characteristics, and explain how we implemented this process within the European Union’s MobiGuide project. In particular, we have developed a mechanism of sequential, piecemeal projection, i.e.,

  18. Distribution patterns of wintering sea ducks in relation to the North Atlantic Oscillation and local environmental characteristics

    Science.gov (United States)

    Zipkin, Elise F.; Gardner, Beth; Gilbert, Andrew T.; O'Connell, Allan F.; Royle, J. Andrew; Silverman, Emily D.

    2010-01-01

    Twelve species of North American sea ducks (Tribe Mergini) winter off the eastern coast of the United States and Canada. Yet, despite their seasonal proximity to urbanized areas in this region, there is limited information on patterns of wintering sea duck habitat use. It is difficult to gather information on sea ducks because of the relative inaccessibility of their offshore locations, their high degree of mobility, and their aggregated distributions. To characterize environmental conditions that affect wintering distributions, as well as their geographic ranges, we analyzed count data on five species of sea ducks (black scoters Melanitta nigra americana, surf scoters M. perspicillata, white-winged scoters M. fusca, common eiders Somateria mollissima, and long-tailed ducks Clangula hyemalis) that were collected during the Atlantic Flyway Sea Duck Survey for ten years starting in the early 1990s. We modeled count data for each species within ten-nautical-mile linear survey segments using a zero-inflated negative binomial model that included four local-scale habitat covariates (sea surface temperature, mean bottom depth, maximum bottom slope, and a variable to indicate if the segment was in a bay or not), one broad-scale covariate (the North Atlantic Oscillation), and a temporal correlation component. Our results indicate that species distributions have strong latitudinal gradients and consistency in local habitat use. The North Atlantic Oscillation was the only environmental covariate that had a significant (but variable) effect on the expected count for all five species, suggesting that broad-scale climatic conditions may be directly or indirectly important to the distributions of wintering sea ducks. Our results provide critical information on species-habitat associations, elucidate the complicated relationship between the North Atlantic Oscillation, sea surface temperature, and local sea duck abundances, and should be useful in assessing the impacts of climate

  19. Local administration of siRNA through Microneedle: Optimization, Bio-distribution, Tumor Suppression and Toxicity

    Science.gov (United States)

    Tang, Tao; Deng, Yan; Chen, Jiao; Zhao, Yi; Yue, Ruifeng; Choy, Kwong Wai; Wang, Chi Chiu; Du, Quan; Xu, Yan; Han, Linxiao; Chung, Tony Kwok Hung

    2016-07-01

    Although RNA interference may become a novel therapeutic approach for cancer treatment, target-site accumulation of siRNA to achieve therapeutic dosage will be a major problem. Microneedle represents a better way to deliver siRNAs and we have evaluated for the first time the capability of a silicon microneedle array for delivery of Gapdh siRNA to the skin in vivo and the results showed that the microneedle arrays could effectively deliver siRNA to relevant regions of the skin noninvasively. For the further study in this field, we evaluated the efficacy of the injectable microneedle device for local delivery of siRNA to the mouse xenograft. The results presented here indicate that local administration of siRNA through injectable microneedle could effectively deliver siRNA into the tumor region, and inhibit tumor progression without major adverse effects.

  20. Model-based leakage localization in drinking water distribution networks using structured residuals

    OpenAIRE

    Puig Cayuela, Vicenç; Rosich, Albert

    2013-01-01

    In this paper, a new model based approach to leakage localization in drinking water networks is proposed based on generating a set of structured residuals. The residual evaluation is based on a numerical method based on an enhanced Newton-Raphson algorithm. The proposed method is suitable for water network systems because the non-linearities of the model make impossible to derive analytical residuals. Furthermore, the computed residuals are designed so that leaks are decoupled, which impro...

  1. Statistical distribution of the local purity in a large quantum system

    International Nuclear Information System (INIS)

    De Pasquale, A; Pascazio, S; Facchi, P; Giovannetti, V; Parisi, G; Scardicchio, A

    2012-01-01

    The local purity of large many-body quantum systems can be studied by following a statistical mechanical approach based on a random matrix model. Restricting the analysis to the case of global pure states, this method proved to be successful, and a full characterization of the statistical properties of the local purity was obtained by computing the partition function of the problem. Here we generalize these techniques to the case of global mixed states. In this context, by uniformly sampling the phase space of states with assigned global mixedness, we determine the exact expression of the first two moments of the local purity and a general expression for the moments of higher order. This generalizes previous results obtained for globally pure configurations. Furthermore, through the introduction of a partition function for a suitable canonical ensemble, we compute the approximate expression of the first moment of the marginal purity in the high-temperature regime. In the process, we establish a formal connection with the theory of quantum twirling maps that provides an alternative, possibly fruitful, way of performing the calculation. (paper)

  2. Action-at-a-distance metamaterials: Distributed local actuation through far-field global forces

    Science.gov (United States)

    Hedayati, R.; Mirzaali, M. J.; Vergani, L.; Zadpoor, A. A.

    2018-03-01

    Mechanical metamaterials are a sub-category of designer materials where the geometry of the material at the small-scale is rationally designed to give rise to unusual properties and functionalities. Here, we propose the concept of "action-at-a-distance" metamaterials where a specific pattern of local deformation is programmed into the fabric of (cellular) materials. The desired pattern of local actuation could then be achieved simply through the application of one single global and far-field force. We proposed graded designs of auxetic and conventional unit cells with changing Poisson's ratios as a way of making "action-at-a-distance" metamaterials. We explored five types of graded designs including linear, two types of radial gradients, checkered, and striped. Specimens were fabricated with indirect additive manufacturing and tested under compression, tension, and shear. Full-field strain maps measured with digital image correlation confirmed different patterns of local actuation under similar far-field strains. These materials have potential applications in soft (wearable) robotics and exosuits.

  3. Action-at-a-distance metamaterials: Distributed local actuation through far-field global forces

    Directory of Open Access Journals (Sweden)

    R. Hedayati

    2018-03-01

    Full Text Available Mechanical metamaterials are a sub-category of designer materials where the geometry of the material at the small-scale is rationally designed to give rise to unusual properties and functionalities. Here, we propose the concept of “action-at-a-distance” metamaterials where a specific pattern of local deformation is programmed into the fabric of (cellular materials. The desired pattern of local actuation could then be achieved simply through the application of one single global and far-field force. We proposed graded designs of auxetic and conventional unit cells with changing Poisson’s ratios as a way of making “action-at-a-distance” metamaterials. We explored five types of graded designs including linear, two types of radial gradients, checkered, and striped. Specimens were fabricated with indirect additive manufacturing and tested under compression, tension, and shear. Full-field strain maps measured with digital image correlation confirmed different patterns of local actuation under similar far-field strains. These materials have potential applications in soft (wearable robotics and exosuits.

  4. The notion of participatory democracy in relation to local ward committees: The distribution of power

    Directory of Open Access Journals (Sweden)

    Leepo J. Modise

    2017-10-01

    Full Text Available This article comprises four important parts: first, the two important components of democracy, namely participatory and non-participatory or representative democracy will be discussed with special reference to the distribution of powers. Second, it will address the roles and responsibilities of ward committees within the democratic society. Third, the ethical question of the basis of the committee members’ capacity to serve on the ward committees in relation to coercive leadership (tyranny of the majority will be investigated. Fourth, the theological standpoint on the distribution of powers or participatory democracy and the role of the church to improve participatory democracy will be discussed. The research question is the following: What can be done by the country to improve participatory democracy in South Africa, through engagement with ward committees?

  5. African and local wind-blown dist contributions at three rural sites in SE Spain: the aerosol size distribution

    International Nuclear Information System (INIS)

    Orza, J. A. G.; Cabello, M.; Lidon, V.; Martinez, J.

    2009-01-01

    The entrainment of particulate material into the atmosphere by wind action on surface soils both disturbed and natural, as well as directly due to human activities like agricultural practices, mineral industry operations, construction works and traffic, is a significant contribution to the aerosol load in Mediterranean semi-arid areas. A further crustal contribution in the region comes from the frequent arrival of African mineral dust plumes. We summarize some of the results obtained after 4-6 month campaigns at three rural sites in SE Spain where the aerosol number size distribution (31 size bins between 0.25 and 32 μm) was continuously measured. The influence of both local wind speed and the arrival of air masses loaded with African dust on the airborne particulate distribution is assessed. Similarities and differences between the three locations give information that allows a better understanding of the influence of both local wind speed and African dust outbreaks (ADO), while highlight what is mostly related to local features. (Author)

  6. Direct measurements show decreasing methane emissions from natural gas local distribution systems in the United States.

    Science.gov (United States)

    Lamb, Brian K; Edburg, Steven L; Ferrara, Thomas W; Howard, Touché; Harrison, Matthew R; Kolb, Charles E; Townsend-Small, Amy; Dyck, Wesley; Possolo, Antonio; Whetstone, James R

    2015-04-21

    Fugitive losses from natural gas distribution systems are a significant source of anthropogenic methane. Here, we report on a national sampling program to measure methane emissions from 13 urban distribution systems across the U.S. Emission factors were derived from direct measurements at 230 underground pipeline leaks and 229 metering and regulating facilities using stratified random sampling. When these new emission factors are combined with estimates for customer meters, maintenance, and upsets, and current pipeline miles and numbers of facilities, the total estimate is 393 Gg/yr with a 95% upper confidence limit of 854 Gg/yr (0.10% to 0.22% of the methane delivered nationwide). This fraction includes emissions from city gates to the customer meter, but does not include other urban sources or those downstream of customer meters. The upper confidence limit accounts for the skewed distribution of measurements, where a few large emitters accounted for most of the emissions. This emission estimate is 36% to 70% less than the 2011 EPA inventory, (based largely on 1990s emission data), and reflects significant upgrades at metering and regulating stations, improvements in leak detection and maintenance activities, as well as potential effects from differences in methodologies between the two studies.

  7. Changes in ultrastructure of rat ovaries after early postnatal x-ray irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, A [Juntendo Univ., Tokyo (Japan). School of Medicine

    1975-02-01

    Female rats were irradiated with 190R of X-rays at 10 days of age and the ovarian ultrastructures were studied 4 and 7 months after irradiation. Ultrastructural changes were found in germinal epithelial cells, in fibroblasts in the tunica albuginea and in interstitial cells. The germinal epithelial cells exhibited various signs of degeneration but no sign of proliferation. Electron density of their basal part was reduced considerably. Their mitochondria became swollen and free ribosomes were decreased in number. The nuclei often protruded from the free surface of these cells. These cells frequently fragmented and, finally, complete desquamation occurred. The basement membrane became unevently thickened. Nuclei of enlarged fibroblasts in the tunica albuginea became irregularly ellipsoid in shape, and the nuclear envelope was occasionally invaginated. Various cytoplasmic organelles of the fibroblasts were well-developed. Some abnormal invasion of cytoplasm into the nucleus was found in the interstitial cells showing the ultrastructural characteristics of steroid hormone synthesis. Various cytoplasmic roganelles and inclusions invaded into the nuclei of these cells and the nuclear envelope sometimes disappeared locally. These interstitial cells contained a large number of irregular-shaped electron dense mitochondria with vesicular cristae, and numerous dilated vesicles of smooth-surfaced endoplasmic reticulum (SER). The cells of the anovular follicles in the irradiated ovaries resembled, in fine structure, the granulosa cells in normal primary follicles of non-irradiated ovaries. These cells seemed to be less affected by early postnatal irradiation.

  8. Stochastic scheduling of local distribution systems considering high penetration of plug-in electric vehicles and renewable energy sources

    International Nuclear Information System (INIS)

    Tabatabaee, Sajad; Mortazavi, Seyed Saeedallah; Niknam, Taher

    2017-01-01

    This paper investigates the optimal scheduling of electric power units in the renewable based local distribution systems considering plug-in electric vehicles (PEVs). The appearance of PEVs in the electric grid can create new challenges for the operation of distributed generations and power units inside the network. In order to deal with this issue, a new stochastic optimization method is devised to let the central controll manage the power units and charging behavior of PEVs. The problem formulation aims to minimize the total cost of the network including the cost of power supply for loads and PEVs as well as the cost of energy not supplied (ENS) as the reliability costs. In order to make PEVs as opportunity for the grid, the vehicle-2-grid (V2G) technology is employed to reduce the operational costs. To model the high uncertain behavior of wind turbine, photovoltaics and the charging and discharging pattern of PEVs, a new stochastic power flow based on unscented transform is proposed. Finally, a new optimization algorithm based on bat algorithm (BA) is proposed to solve the problem optimally. The satisfying performance of the proposed stochastic method is tested on a grid-connected local distribution system. - Highlights: • Introduction of stochastic method to assess Plug-in Electric Vehicles effects on the microgrid. • Assessing the role of V2G technology on battery aging and degradation costs. • Use of BA for solving the proposed problem. • Introduction of a new modification method for the BA.

  9. Measuring agglomerate size distribution and dependence of localized surface plasmon resonance absorbance on gold nanoparticle agglomerate size using analytical ultracentrifugation.

    Science.gov (United States)

    Zook, Justin M; Rastogi, Vinayak; Maccuspie, Robert I; Keene, Athena M; Fagan, Jeffrey

    2011-10-25

    Agglomeration of nanoparticles during measurements in relevant biological and environmental media is a frequent problem in nanomaterial property characterization. The primary problem is typically that any changes to the size distribution can dramatically affect the potential nanotoxicity or other size-determined properties, such as the absorbance signal in a biosensor measurement. Herein we demonstrate analytical ultracentrifugation (AUC) as a powerful method for measuring two critical characteristics of nanoparticle (NP) agglomerates in situ in biological media: the NP agglomerate size distribution, and the localized surface plasmon resonance (LSPR) absorbance spectrum of precise sizes of gold NP agglomerates. To characterize the size distribution, we present a theoretical framework for calculating the hydrodynamic diameter distribution of NP agglomerates from their sedimentation coefficient distribution. We measure sedimentation rates for monomers, dimers, and trimers, as well as for larger agglomerates with up to 600 NPs. The AUC size distributions were found generally to be broader than the size distributions estimated from dynamic light scattering and diffusion-limited colloidal aggregation theory, an alternative bulk measurement method that relies on several assumptions. In addition, the measured sedimentation coefficients can be used in nanotoxicity studies to predict how quickly the agglomerates sediment out of solution under normal gravitational forces, such as in the environment. We also calculate the absorbance spectra for monomer, dimer, trimer, and larger gold NP agglomerates up to 600 NPs, to enable a better understanding of LSPR biosensors. Finally, we validate a new method that uses these spectra to deconvolute the net absorbance spectrum of an unknown bulk sample and approximate the proportions of monomers, dimers, and trimers in a polydisperse sample of small agglomerates, so that every sample does not need to be measured by AUC. These results

  10. Colleters in Caryocar brasiliense (Caryocaraceae ontogenesis, ultrastructure and secretion

    Directory of Open Access Journals (Sweden)

    E. A. S. Paiva

    Full Text Available Colleters are widely distributed and have been reported in several taxa. However, the only report of colleters in the Caryocaraceae family is in Caryocar brasiliense. This study purports to describe the distribution, structure and ultrastructure of colleters in C. brasiliense. Vegetative shoot apices with stipules in different stages of development were collected, fixed, and processed by light, transmission and scanning electron microscopy. Colleters occur on the stipule adaxial face and are differentiated on younger stipules, remaining functional until senescence. Stipules are deciduous, falling before the beginning of leaf expansion. Colleter secretion is abundant, filling all the space delimited by the stipule. Colleter origin is mixed, involving the protoderm and ground meristem. In this species, colleters are finger-shaped, consisting of a column of non-secretory central cells and a secretory epithelium whose cells are arranged in palisades. Secretory epithelium cells show dense cytoplasm, rough endoplasmic reticulum (RER segments, free ribosomes, mitochondria, and abundant well developed dictyosomes. The colleters central cell shows a flocculated cytoplasm and developed vacuole. These cells have a small lobated nucleus with an inconspicuous nucleolus. Mitochondria and RER stand out in the organelles. There is evidence of granulocrine secretion and colleter involvement with protection of the apical meristem and leaves in the initial stages of development.

  11. Local and latitudinal variation in abundance: the mechanisms shaping the distribution of an ecosystem engineer.

    Science.gov (United States)

    Crutsinger, Gregory M; Gonzalez, Angélica L; Crawford, Kerri M; Sanders, Nathan J

    2013-01-01

    Ecological processes that determine the abundance of species within ecological communities vary across space and time. These scale-dependent processes are especially important when they affect key members of a community, such as ecosystem engineers that create shelter and food resources for other species. Yet, few studies have examined the suite of processes that shape the abundance of ecosystem engineers. Here, we evaluated the relative influence of temporal variation, local processes, and latitude on the abundance of an engineering insect-a rosette-galling midge, Rhopalomyia solidaginis (Diptera: Cecidomyiidae). Over a period of 3-5 years, we studied the density and size of galls across a suite of local experiments that manipulated genetic variation, soil nutrient availability, and the removal of other insects from the host plant, Solidago altissima (tall goldenrod). We also surveyed gall density within a single growing season across a 2,300 km latitudinal transect of goldenrod populations in the eastern United States. At the local scale, we found that host-plant genotypic variation was the best predictor of rosette gall density and size within a single year. We found that the removal of other insect herbivores resulted in an increase in gall density and size. The amendment of soil nutrients for four years had no effect on gall density, but galls were smaller in carbon-added plots compared to control and nitrogen additions. Finally, we observed that gall density varied several fold across years. At the biogeographic scale, we observed that the density of rosette gallers peaked at mid-latitudes. Using meta-analytic approaches, we found that the effect size of time, followed by host-plant genetic variation and latitude were the best predictors of gall density. Taken together, our study provides a unique comparison of multiple factors across different spatial and temporal scales that govern engineering insect herbivore density.

  12. Advanced Twisted Pair Cables for Distributed Local Area Networks in Intelligent Structure Systems

    Science.gov (United States)

    Semenov, Andrey

    2018-03-01

    The possibility of a significant increase in the length of cable communication channels of local area networks of automation and engineering support systems of buildings in the case of their implementation on balanced twisted pair cables is shown. Assuming a direct connection scheme and an effective speed of 100 Mbit/s, analytical relationships are obtained for the calculation of the maximum communication distance. The necessity of using in the linear part of such systems of twisted pair cables with U/UTP structure and interference parameters at the level of category 5e is grounded.

  13. INTEGRATED MANAGEMENT SYSTEMS IN LOCAL PUBLIC ENTERPRIZE FOR PRODUCTION, DISTRIBUTION AND CLEANING OF WASTED WATER

    Directory of Open Access Journals (Sweden)

    Slavko Arsovski

    2007-06-01

    Full Text Available Appearance of large number of management systems, with different and sometimes divergent demands, needs reconsideration of their implementation strategies and their integration in one integrated management system (IMS. So defined IMS would be designed and implemented in different areas. In this paper is presented basic concept of integration of partical management systems in areas of quality (ISO 9001, environmental protection (ISO 14001, occupational health (ISO 18001, food safety (ISO 22000 and accreditation of laboratories (ISO17025/ISO17020. As a pilot organization is choosed local public enterprise for production, supply and drain of water.

  14. Ultrastructural characteristics of spermatogenesis in Pallas's mastiff bat, Molossus molossus (Chiroptera: Molossidae).

    Science.gov (United States)

    Beguelini, Mateus R; Taboga, Sebastião R; Morielle-Versute, Eliana

    2012-07-01

    Despite the large number of species, their wide distribution, and unique reproductive characteristics, Neotropical bats have been poorly studied, and important aspects of the reproduction of these animals have not been elucidated. We made an ultrastructural analysis of spermatogenesis in Molossus molossus (Molossidae). The process of spermatogonial differentiation is similar to that found in other bats and is also relatively similar to that of Primates, with three main spermatogonia types: A(d), A(p), and B. Meiotic divisions proceed similarly to those of most mammals, and spermiogenesis is clearly divided into 12 steps, in the middle of the range known for bats (9-16 steps). Formation of the acrosome is similar to that known from other mammals; however, the ultrastructure of spermatozoa was found to have unique characteristics, including many wavy acrosomal projections on its surface, which seems to be specific for the family Molossidae. Comparing the ultrastructure of the spermatozoon of M. molossus with other bats already study, we observed that three characters vary: morphology of the outer dense fibers, of the perforatorium, and of the spermatozoon head. The great similarity of morphological characters between M. molossus and Platyrrhinus lineatus suggests that M. molossus is more closely related to the Phyllostomidae than to the Rhinolophidae and the Vespertilionidae. Copyright © 2012 Wiley Periodicals, Inc.

  15. Distribution of Endogenous NO Regulates Early Gravitropic Response and PIN2 Localization in Arabidopsis Roots

    Directory of Open Access Journals (Sweden)

    Ramiro París

    2018-04-01

    Full Text Available High-resolution and automated image analysis of individual roots demonstrated that endogenous nitric oxide (NO contribute significantly to gravitropism of Arabidopsis roots. Lowering of endogenous NO concentrations strongly reduced and even reversed gravitropism, resulting in upward bending, without affecting root growth rate. Notably, the asymmetric accumulation of NO along the upper and lower sides of roots correlated with a positive gravitropic response. Detection of NO by the specific DAF-FM DA fluorescent probe revealed that NO was higher at the lower side of horizontally-oriented roots returning to initial values 2 h after the onset of gravistimulation. We demonstrate that NO promotes plasma membrane re-localization of PIN2 in epidermal cells, which is required during the early root gravitropic response. The dynamic and asymmetric localization of both auxin and NO is critical to regulate auxin polar transport during gravitropism. Our results collectively suggest that, although auxin and NO crosstalk occurs at different levels of regulation, they converge in the regulation of PIN2 membrane trafficking in gravistimulated roots, supporting the notion that a temporally and spatially coordinated network of signal molecules could participate in the early phases of auxin polar transport during gravitropism.

  16. Distributed, signal strength-based indoor localization algorithm for use in healthcare environments.

    Science.gov (United States)

    Wyffels, Jeroen; De Brabanter, Jos; Crombez, Pieter; Verhoeve, Piet; Nauwelaers, Bart; De Strycker, Lieven

    2014-11-01

    In current healthcare environments, a trend toward mobile and personalized interactions between people and nurse call systems is strongly noticeable. Therefore, it should be possible to locate patients at all times and in all places throughout the care facility. This paper aims at describing a method by which a mobile node can locate itself indoors, based on signal strength measurements and a minimal amount of yes/no decisions. The algorithm has been developed specifically for use in a healthcare environment. With extensive testing and statistical support, we prove that our algorithm can be used in a healthcare setting with an envisioned level of localization accuracy up to room revel (or region level in a corridor), while avoiding heavy investments since the hardware of an existing nurse call network can be reused. The approach opted for leads to very high scalability, since thousands of mobile nodes can locate themselves. Network timing issues and localization update delays are avoided, which ensures that a patient can receive the needed care in a time and resources efficient way.

  17. Wearable Sensor Localization Considering Mixed Distributed Sources in Health Monitoring Systems.

    Science.gov (United States)

    Wan, Liangtian; Han, Guangjie; Wang, Hao; Shu, Lei; Feng, Nanxing; Peng, Bao

    2016-03-12

    In health monitoring systems, the base station (BS) and the wearable sensors communicate with each other to construct a virtual multiple input and multiple output (VMIMO) system. In real applications, the signal that the BS received is a distributed source because of the scattering, reflection, diffraction and refraction in the propagation path. In this paper, a 2D direction-of-arrival (DOA) estimation algorithm for incoherently-distributed (ID) and coherently-distributed (CD) sources is proposed based on multiple VMIMO systems. ID and CD sources are separated through the second-order blind identification (SOBI) algorithm. The traditional estimating signal parameters via the rotational invariance technique (ESPRIT)-based algorithm is valid only for one-dimensional (1D) DOA estimation for the ID source. By constructing the signal subspace, two rotational invariant relationships are constructed. Then, we extend the ESPRIT to estimate 2D DOAs for ID sources. For DOA estimation of CD sources, two rational invariance relationships are constructed based on the application of generalized steering vectors (GSVs). Then, the ESPRIT-based algorithm is used for estimating the eigenvalues of two rational invariance matrices, which contain the angular parameters. The expressions of azimuth and elevation for ID and CD sources have closed forms, which means that the spectrum peak searching is avoided. Therefore, compared to the traditional 2D DOA estimation algorithms, the proposed algorithm imposes significantly low computational complexity. The intersecting point of two rays, which come from two different directions measured by two uniform rectangle arrays (URA), can be regarded as the location of the biosensor (wearable sensor). Three BSs adopting the smart antenna (SA) technique cooperate with each other to locate the wearable sensors using the angulation positioning method. Simulation results demonstrate the effectiveness of the proposed algorithm.

  18. Abiotic and biotic controls on local spatial distribution and performance of Boechera stricta

    Directory of Open Access Journals (Sweden)

    KUSUM J NAITHANI

    2014-07-01

    Full Text Available This study investigates the relative influence of biotic and abiotic factors on community dynamics using an integrated approach and highlights the influence of space on genotypic and phenotypic traits in plant community structure. We examined the relative influence of topography, environment, spatial distance, and intra- and interspecific interactions on spatial distribution and performance of Boechera stricta (rockcress, a close perennial relative of model plant Arabidopsis. First, using Bayesian kriging, we mapped the topography and environmental gradients and explored the spatial distribution of naturally occurring rockcress plants and two neighbors, Taraxacum officinale (dandelion and Solidago missouriensis (goldenrod found in close proximity within a typical diverse meadow community across topographic and environmental gradients. We then evaluated direct and indirect relationships among variables using Mantel path analysis and developed a network displaying abiotic and biotic interactions in this community. We found significant spatial autocorrelation among rockcress individuals, either because of common microhabitats as displayed by high density of individuals at lower elevation and high soil moisture area, or limited dispersal as shown by significant spatial autocorrelation of naturally occurring inbred lines, or a combination of both. Goldenrod and dandelion density around rockcress does not show any direct relationship with rockcress fecundity, possibly due to spatial segregation of resources. However, dandelion density around rockcress shows an indirect negative influence on rockcress fecundity via herbivory, indicating interspecific competition. Overall, we suggest that common microhabitat preference and limited dispersal are the main drivers for spatial distribution. However, intra-specific interactions and insect herbivory are the main drivers of rockcress performance in the meadow community.

  19. Feasibility study of Self Powered Neutron Detectors in Fast Reactors for detecting local change in neutron flux distribution

    International Nuclear Information System (INIS)

    Jammes, Christian; Filliatre, Philippe; Verma, Vasudha; Hellesen, Carl; Jacobsson Svard, Staffan

    2015-01-01

    Neutron flux monitoring system forms an integral part of the design of a Generation IV sodium cooled fast reactor system. Diverse possibilities of detector systems installation have to be investigated with respect to practicality and feasibility according to the detection parameters. In this paper, we demonstrate the feasibility of using self powered neutron detectors as in-core detectors in fast reactors for detecting local change in neutron flux distribution. We show that the gamma contribution from fission products decay in the fuel and activation of structural materials is very small compared to the fission gammas. Thus, it is possible for the in-core SPND signal to follow changes in local neutron flux as they are proportional to each other. This implies that the signal from an in-core SPND can provide dynamic information on the neutron flux perturbations occurring inside the reactor core. (authors)

  20. Feasibility study of Self Powered Neutron Detectors in Fast Reactors for detecting local change in neutron flux distribution

    Energy Technology Data Exchange (ETDEWEB)

    Jammes, Christian; Filliatre, Philippe [CEA, DEN, DER, Instrumentation Sensors and Dosimetry Laboratory, Cadarache, F-13108 St Paul-Lez-Durance, (France); Verma, Vasudha; Hellesen, Carl; Jacobsson Svard, Staffan [Division of Applied Nuclear Physics, Uppsala University, SE-75120 Uppsala, (Sweden)

    2015-07-01

    Neutron flux monitoring system forms an integral part of the design of a Generation IV sodium cooled fast reactor system. Diverse possibilities of detector systems installation have to be investigated with respect to practicality and feasibility according to the detection parameters. In this paper, we demonstrate the feasibility of using self powered neutron detectors as in-core detectors in fast reactors for detecting local change in neutron flux distribution. We show that the gamma contribution from fission products decay in the fuel and activation of structural materials is very small compared to the fission gammas. Thus, it is possible for the in-core SPND signal to follow changes in local neutron flux as they are proportional to each other. This implies that the signal from an in-core SPND can provide dynamic information on the neutron flux perturbations occurring inside the reactor core. (authors)

  1. Zinc distribution and localization in primed maize seeds and its translocation during early seedling development

    DEFF Research Database (Denmark)

    Imran, Muhammad; Garbe-Schönberg, Dieter; Neumann, Günter

    2017-01-01

    Zinc (Zn) priming is a technique used to increase seed Zn reserves for improving seed quality, crop growth, and enhancing stress tolerance in crop plants. The present study demonstrated the effect of water and Zn priming on the distribution and accumulation of endogenous and primed Zn in maize...... seeds (Zea mays L.). Zn concentration in unprimed, water and Zn primed seeds and germinated seedlings were analyzed by ICP-MS (Inductivity Coupled Plasma Mass Spectroscopy). DTZ (Diphenyle Thio-Carbazone) staining method and LA-ICP-MS (Laser Ablation Inductivity Coupled Plasma Mass Spectroscopy...

  2. Heterogeneity of acute myeloblastic leukemia without maturation: an ultrastructural study.

    Science.gov (United States)

    Hamamoto, K; Date, M; Taniguchi, H; Nagano, T; Kishimoto, Y; Kimura, T; Fukuhara, S

    1995-01-01

    We demonstrated by ultrastructural examination that the leukemic blasts of 13 patients with acute myeloblastic leukemia (AML) without maturation (M1 in the French-American-British classification) showed heterogeneous features. In 7 patients, the leukemic blasts had a high level of light microscopic myeloperoxidase positivity (> 50%). Ultrastructurally, the cells were myeloblast-promyelocytes with 100% myeloperoxidase positivity, and these 7 patients appeared to have typical AML. In contrast, the remaining 6 patients had leukemic blasts with a low myeloperoxidase positivity (undifferentiated blasts. The former group had a better prognosis than the latter, indicating that ultrastructural analysis of M1 leukemia may help predict the response to therapy.

  3. The Localized Discovery and Recovery for Query Packet Losses in Wireless Sensor Networks with Distributed Detector Clusters

    Directory of Open Access Journals (Sweden)

    Ryu Miura

    2013-06-01

    Full Text Available An essential application of wireless sensor networks is to successfully respond to user queries. Query packet losses occur in the query dissemination due to wireless communication problems such as interference, multipath fading, packet collisions, etc. The losses of query messages at sensor nodes result in the failure of sensor nodes reporting the requested data. Hence, the reliable and successful dissemination of query messages to sensor nodes is a non-trivial problem. The target of this paper is to enable highly successful query delivery to sensor nodes by localized and energy-efficient discovery, and recovery of query losses. We adopt local and collective cooperation among sensor nodes to increase the success rate of distributed discoveries and recoveries. To enable the scalability in the operations of discoveries and recoveries, we employ a distributed name resolution mechanism at each sensor node to allow sensor nodes to self-detect the correlated queries and query losses, and then efficiently locally respond to the query losses. We prove that the collective discovery of query losses has a high impact on the success of query dissemination and reveal that scalability can be achieved by using the proposed approach. We further study the novel features of the cooperation and competition in the collective recovery at PHY and MAC layers, and show that the appropriate number of detectors can achieve optimal successful recovery rate. We evaluate the proposed approach with both mathematical analyses and computer simulations. The proposed approach enables a high rate of successful delivery of query messages and it results in short route lengths to recover from query losses. The proposed approach is scalable and operates in a fully distributed manner.

  4. Semiempirical theory of level spacing distribution beyond the Berry-Robnik regime: modeling the localization and the tunneling effects

    International Nuclear Information System (INIS)

    Batistic, Benjamin; Robnik, Marko

    2010-01-01

    In this work we study the level spacing distribution in the classically mixed-type quantum systems (which are generic), exhibiting regular motion on invariant tori for some initial conditions and chaotic motion for the complementary initial conditions. In the asymptotic regime of the sufficiently deep semiclassical limit (sufficiently small effective Planck constant) the Berry and Robnik (1984 J. Phys. A: Math. Gen. 17 2413) picture applies, which is very well established. We present a new quasi-universal semiempirical theory of the level spacing distribution in a regime away from the Berry-Robnik regime (the near semiclassical limit), by describing both the dynamical localization effects of chaotic eigenstates, and the tunneling effects which couple regular and chaotic eigenstates. The theory works extremely well in the 2D mixed-type billiard system introduced by Robnik (1983 J. Phys. A: Math. Gen. 16 3971) and is also tested in other systems (mushroom billiard and Prosen billiard).

  5. Local area distribution of fallout radionuclides from Fukushima Daiichi Nuclear Power Plant determined by autoradiography analysis

    International Nuclear Information System (INIS)

    Sakamoto, Fuminori; Ohnuki, Toshihiko; Kozai, Naofumi; Igarashi, Shosuke; Yamasaki, Shinya; Yoshida, Zenko; Tanaka, Shunichi

    2012-01-01

    The environmental behavior of radioactive Cs in the fallout from the accident of the Fukushima Daiichi Nuclear Power Plant has been studied by measuring its spatial distribution on/in trees, plants, and surface soil beneath the plants using autoradiography analysis. The results of autoradiography analysis showed that radioactive Cs was distributed on the branches and leaves of trees that were present during the accident and that only a small fraction of radioactive Cs was transported to new branches and leaves grown after the accident. Radioactive Cs was present on the grass and rice stubble on the soils, but not in the soils beneath the grass and rice stubble, indicating that the radioactive Cs was deposited on the grass and the rice plant. In addition, the ratio of the radioactive Cs that penetrated into the soil layer by weathering was very small two months after the accident. These results indicate that trees and other plants are the reservoir of the fallout Cs and function to retard the fallout Cs migration with rain water. (author)

  6. THE STELLAR NUMBER DENSITY DISTRIBUTION IN THE LOCAL SOLAR NEIGHBORHOOD IS NORTH-SOUTH ASYMMETRIC

    Energy Technology Data Exchange (ETDEWEB)

    Yanny, Brian [Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Gardner, Susan [Department of Physics and Astronomy, University of Kentucky, Lexington, KY 40506-0055 (United States)

    2013-11-10

    We study the number density distribution of a sample of K and M dwarf stars, matched north and south of the Galactic plane within a distance of 2 kpc from the Sun, using observations from the Ninth Data Release of the Sloan Digital Sky Survey. We determine distances using the photometric parallax method, and in this context systematic effects exist which could potentially impact the determination of the number density profile with height from the Galactic plane—and ultimately affect a number density north-south asymmetry. They include: (1) the calibration of the various photometric parallax relations, (2) the ability to separate dwarfs from giants in our sample, (3) the role of stellar population differences such as age and metallicity, (4) the ability to determine the offset of the Sun from the Galactic plane, and (5) the correction for reddening from dust in the Galactic plane, though our stars are at high Galactic latitudes. We find the various analyzed systematic effects to have a negligible impact on our observed asymmetry, and using a new and larger sample of stars we confirm and refine the earlier discovery of Widrow et al. of a significant Galactic north-south asymmetry in the stellar number density distribution.

  7. THE STELLAR NUMBER DENSITY DISTRIBUTION IN THE LOCAL SOLAR NEIGHBORHOOD IS NORTH-SOUTH ASYMMETRIC

    Energy Technology Data Exchange (ETDEWEB)

    Yanny, Brian; Gardner, Susan

    2013-10-17

    We study the number density distribution of a sample of K and M dwarf stars, matched North and South of the Galactic plane within a distance of 2 kpc from the sun, using observations from the Ninth Data Release of the Sloan Digital Sky Survey. We determine distances using the photometric parallax method, and in this context systematic effects exist which could potentially impact the determination of the number density profile with height from the Galactic plane --- and ultimately affect a number density North-South asymmetry. They include: (i) the calibration of the various photometric parallax relations, (ii) the ability to separate dwarfs from giants in our sample, (iii) the role of stellar population differences such as age and metallicity, (iv) the ability to determine the offset of the sun from the Galactic plane, and (v) the correction for reddening from dust in the Galactic plane, though our stars are at high Galactic latitudes. We find the various analyzed systematic effects to have a negligible impact on our observed asymmetry, and using a new and larger sample of stars we confirm and refine the earlier discovery of Widrow et al. of a significant Galactic North-South asymmetry in the stellar number density distribution.

  8. Optimization of the kernel functions in a probabilistic neural network analyzing the local pattern distribution.

    Science.gov (United States)

    Galleske, I; Castellanos, J

    2002-05-01

    This article proposes a procedure for the automatic determination of the elements of the covariance matrix of the gaussian kernel function of probabilistic neural networks. Two matrices, a rotation matrix and a matrix of variances, can be calculated by analyzing the local environment of each training pattern. The combination of them will form the covariance matrix of each training pattern. This automation has two advantages: First, it will free the neural network designer from indicating the complete covariance matrix, and second, it will result in a network with better generalization ability than the original model. A variation of the famous two-spiral problem and real-world examples from the UCI Machine Learning Repository will show a classification rate not only better than the original probabilistic neural network but also that this model can outperform other well-known classification techniques.

  9. Generalized Gibbs distribution and energy localization in the semiclassical FPU problem

    Science.gov (United States)

    Hipolito, Rafael; Danshita, Ippei; Oganesyan, Vadim; Polkovnikov, Anatoli

    2011-03-01

    We investigate dynamics of the weakly interacting quantum mechanical Fermi-Pasta-Ulam (qFPU) model in the semiclassical limit below the stochasticity threshold. Within this limit we find that initial quantum fluctuations lead to the damping of FPU oscillations and relaxation of the system to a slowly evolving steady state with energy localized within few momentum modes. We find that in large systems this state can be described by the generalized Gibbs ensemble (GGE), with the Lagrange multipliers being very weak functions of time. This ensembles gives accurate description of the instantaneous correlation functions, both quadratic and quartic. Based on these results we conjecture that GGE generically appears as a prethermalized state in weakly non-integrable systems.

  10. Tissue distribution and tumour localization of 99m-technetium-labelled liposomes in cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, V J; Ryman, B E; Jewkes, R F; Jeyasingh, K; Tattersall, M N.H.; Newlands, E S; Kaye, S B

    1979-07-01

    The possible use of liposomes (Phospholipid vesicles) to direct cytotoxic drugs to tumours led to the investigation of the tissue localization of i.v. injected sup(99m) Tc-labelled liposomes in cancer patients. 20 mg or 300 mg doses of liposomal lipid (7:2:1 molar ratio of phosphatidylcholine: cholesterol: phosphatidic acid) were used in a study of 13 patients with advanced cancer and one with polycythaemia rubra vera (PRV). In all cases except the patient with PRV the major site of uptake of the label was the liver and spleen. In the patient with PRV the liver uptake was greatly reduced and the major site of uptake was found in regions corresponding to marrow. With the exception of one patient with a primary hepatoma, there was no significant tumour uptake of the label.

  11. Distributed Pedestrian Detection Alerts Based on Data Fusion with Accurate Localization

    Directory of Open Access Journals (Sweden)

    Arturo de la Escalera

    2013-09-01

    Full Text Available Among Advanced Driver Assistance Systems (ADAS pedestrian detection is a common issue due to the vulnerability of pedestrians in the event of accidents. In the present work, a novel approach for pedestrian detection based on data fusion is presented. Data fusion helps to overcome the limitations inherent to each detection system (computer vision and laser scanner and provides accurate and trustable tracking of any pedestrian movement. The application is complemented by an efficient communication protocol, able to alert vehicles in the surroundings by a fast and reliable communication. The combination of a powerful location, based on a GPS with inertial measurement, and accurate obstacle localization based on data fusion has allowed locating the detected pedestrians with high accuracy. Tests proved the viability of the detection system and the efficiency of the communication, even at long distances. By the use of the alert communication, dangerous situations such as occlusions or misdetections can be avoided.

  12. Distributed pedestrian detection alerts based on data fusion with accurate localization.

    Science.gov (United States)

    García, Fernando; Jiménez, Felipe; Anaya, José Javier; Armingol, José María; Naranjo, José Eugenio; de la Escalera, Arturo

    2013-09-04

    Among Advanced Driver Assistance Systems (ADAS) pedestrian detection is a common issue due to the vulnerability of pedestrians in the event of accidents. In the present work, a novel approach for pedestrian detection based on data fusion is presented. Data fusion helps to overcome the limitations inherent to each detection system (computer vision and laser scanner) and provides accurate and trustable tracking of any pedestrian movement. The application is complemented by an efficient communication protocol, able to alert vehicles in the surroundings by a fast and reliable communication. The combination of a powerful location, based on a GPS with inertial measurement, and accurate obstacle localization based on data fusion has allowed locating the detected pedestrians with high accuracy. Tests proved the viability of the detection system and the efficiency of the communication, even at long distances. By the use of the alert communication, dangerous situations such as occlusions or misdetections can be avoided.

  13. Conventional and conformal technique of external beam radiotherapy in locally advanced cervical cancer: Dose distribution, tumor response, and side effects

    Science.gov (United States)

    Mutrikah, N.; Winarno, H.; Amalia, T.; Djakaria, M.

    2017-08-01

    The objective of this study was to compare conventional and conformal techniques of external beam radiotherapy (EBRT) in terms of the dose distribution, tumor response, and side effects in the treatment of locally advanced cervical cancer patients. A retrospective cohort study was conducted on cervical cancer patients who underwent EBRT before brachytherapy in the Radiotherapy Department of Cipto Mangunkusumo Hospital. The prescribed dose distribution, tumor response, and acute side effects of EBRT using conventional and conformal techniques were investigated. In total, 51 patients who underwent EBRT using conventional techniques (25 cases using Cobalt-60 and 26 cases using a linear accelerator (LINAC)) and 29 patients who underwent EBRT using conformal techniques were included in the study. The distribution of the prescribed dose in the target had an impact on the patient’s final response to EBRT. The complete response rate of patients to conformal techniques was significantly greater (58%) than that of patients to conventional techniques (42%). No severe acute local side effects were seen in any of the patients (Radiation Therapy Oncology Group (RTOG) grades 3-4). The distribution of the dose and volume to the gastrointestinal tract affected the proportion of mild acute side effects (RTOG grades 1-2). The urinary bladder was significantly greater using conventional techniques (Cobalt-60/LINAC) than using conformal techniques at 72% and 78% compared to 28% and 22%, respectively. The use of conformal techniques in pelvic radiation therapy is suggested in radiotherapy centers with CT simulators and 3D Radiotherapy Treatment Planning Systems (RTPSs) to decrease some uncertainties in radiotherapy planning. The use of AP/PA pelvic radiation techniques with Cobalt-60 should be limited in body thicknesses equal to or less than 18 cm. When using conformal techniques, delineation should be applied in the small bowel, as it is considered a critical organ according to RTOG

  14. Modelling chemical abundance distributions for dwarf galaxies in the Local Group: the impact of turbulent metal diffusion

    Science.gov (United States)

    Escala, Ivanna; Wetzel, Andrew; Kirby, Evan N.; Hopkins, Philip F.; Ma, Xiangcheng; Wheeler, Coral; Kereš, Dušan; Faucher-Giguère, Claude-André; Quataert, Eliot

    2018-02-01

    We investigate stellar metallicity distribution functions (MDFs), including Fe and α-element abundances, in dwarf galaxies from the Feedback in Realistic Environment (FIRE) project. We examine both isolated dwarf galaxies and those that are satellites of a Milky Way-mass galaxy. In particular, we study the effects of including a sub-grid turbulent model for the diffusion of metals in gas. Simulations that include diffusion have narrower MDFs and abundance ratio distributions, because diffusion drives individual gas and star particles towards the average metallicity. This effect provides significantly better agreement with observed abundance distributions in dwarf galaxies in the Local Group, including small intrinsic scatter in [α/Fe] versus [Fe/H] of ≲0.1 dex. This small intrinsic scatter arises in our simulations because the interstellar medium in dwarf galaxies is well mixed at nearly all cosmic times, such that stars that form at a given time have similar abundances to ≲0.1 dex. Thus, most of the scatter in abundances at z = 0 arises from redshift evolution and not from instantaneous scatter in the ISM. We find similar MDF widths and intrinsic scatter for satellite and isolated dwarf galaxies, which suggests that environmental effects play a minor role compared with internal chemical evolution in our simulations. Overall, with the inclusion of metal diffusion, our simulations reproduce abundance distribution widths of observed low-mass galaxies, enabling detailed studies of chemical evolution in galaxy formation.

  15. Ultrastructural diversity between centrioles of eukaryotes.

    Science.gov (United States)

    Gupta, Akshari; Kitagawa, Daiju

    2018-02-16

    Several decades of centriole research have revealed the beautiful symmetry present in these microtubule-based organelles, which are required to form centrosomes, cilia, and flagella in many eukaryotes. Centriole architecture is largely conserved across most organisms, however, individual centriolar features such as the central cartwheel or microtubule walls exhibit considerable variability when examined with finer resolution. Here, we review the ultrastructural characteristics of centrioles in commonly studied organisms, highlighting the subtle and not-so-subtle differences between specific structural components of these centrioles. Additionally, we survey some non-canonical centriole structures that have been discovered in various species, from the coaxial bicentrioles of protists and lower land plants to the giant irregular centrioles of the fungus gnat Sciara. Finally, we speculate on the functional significance of these differences between centrioles, and the contribution of individual structural elements such as the cartwheel or microtubules towards the stability of centrioles.Centriole structure, cartwheel, triplet microtubules, SAS-6, centrosome.

  16. Ultrastructure of developing ascospores in Sordaria brevicollis.

    Science.gov (United States)

    Hackett, C J; Chen, K C

    1976-05-01

    The ultrastructure of ascospore wall formation in the pyrenomycete Sordaria brevicollis was studied in developing asci at progressive time intervals. From early spore delimitation through final stage of maturation, the wall of the ascospore differentiated into four composite layers, the periascosporium the delineation ascosporium, the subascosproium, and the endoascosproium, While ascospores were at the hyaline stage of development,they possessed only the periascosporium and delineation ascosporium as their wall components. At about 7 to 8 days from the initiation of the cross, the spores developed a yellow color, and this coloration was always associated with the elaboration of the subascorsporium just internal to the ascosporium. Asthe spores continued to progressively darken in color, the subascosporium was seen to increase in complexity, electron density, and thickness. Soon after the formation of the subascosporium, the endoascosporium began to develop de novo and was, therefore, the last wall layer formed as the spore approached maturity.

  17. Somatostatinoma: collision with neurofibroma and ultrastructural features.

    Science.gov (United States)

    Varikatt, W; Yong, J L C; Killingsworth, M C

    2006-11-01

    The clinical presentation, histopathology and immunoelectron microscopic features of two cases of duodenal somatostatinoma are described, one of which is a hitherto unreported example of a collision tumour with a neurofibroma. Ultrastructural morphometric immunoelectron microscopy studies revealed the presence of four types of cells in both tumours, but there was no difference in the proportions of these cells between the collision tumour and the non-collision tumour. Neurosecretory granules ranging in size from 255-815 nm were generally larger than those previously reported for somatostatinomas and somatostatin was identified in granules of all sizes across this range. Neither tumour was associated with the somatostatinoma syndrome comprising associated diabetes mellitis, steatorrhoea and cholelithiasis.

  18. Ultrastructure and properties of Paecilomyces lilacinus spores

    Energy Technology Data Exchange (ETDEWEB)

    Holland, R.J.; Gunasekera, T.S. [Macquarie Univ., Dept. of Biological Sciences, Sydney (Australia); Williams, K.L. [Proteome Systems Ltd., Sydney (Australia); Nevalainen, K.M.H. [Dept. of Biological Sciences, Macquarie University, Sydney (Australia)

    2002-10-01

    Strains of the filamentous soil fungus Paecilomyces lilacinus are currently being developed for use as biological control agents against root-knot, cyst, and other plant-parasitic nematodes. The inoculum applied in the field consists mainly of spores. This study was undertaken to examine the size, ultrastructure, and rodlet layers of P. lilacinus spores and the effect of the culture method on structural and functional spore properties. A rodlet layer was identified on aerial spores only. Other differences noted between aerial spores and those produced in submerged culture included the size and appearance of spores and thickness of spore coat layers when examined with transmission electron microscopy. The two spore types differed in UV tolerance, with aerial spores being less sensitive to environmentally relevant UV radiation. Also, viability after drying and storage was better with the aerial spores. Both spore types exhibited similar nematophagous ability. (author)

  19. Ultrastructure and properties of Paecilomyces lilacinus spores

    International Nuclear Information System (INIS)

    Holland, R.J.; Gunasekera, T.S.; Williams, K.L.; Nevalainen, K.M.H.

    2002-01-01

    Strains of the filamentous soil fungus Paecilomyces lilacinus are currently being developed for use as biological control agents against root-knot, cyst, and other plant-parasitic nematodes. The inoculum applied in the field consists mainly of spores. This study was undertaken to examine the size, ultrastructure, and rodlet layers of P. lilacinus spores and the effect of the culture method on structural and functional spore properties. A rodlet layer was identified on aerial spores only. Other differences noted between aerial spores and those produced in submerged culture included the size and appearance of spores and thickness of spore coat layers when examined with transmission electron microscopy. The two spore types differed in UV tolerance, with aerial spores being less sensitive to environmentally relevant UV radiation. Also, viability after drying and storage was better with the aerial spores. Both spore types exhibited similar nematophagous ability. (author)

  20. Localization, distribution, and connectivity of neuropeptide Y in the human and porcine retinas - a comparative study

    DEFF Research Database (Denmark)

    Christiansen, Anders Tolstrup; Kiilgaard, Jens Folke; Klemp, Kristian

    2018-01-01

    retinal signaling. These findings extend existing knowledge on NPY and NPY-expressing cells in the human and porcine retina showing a high degree of comparability. The extensive distribution and connectivity of NPY-ir cells described in the present study further highlights the potential importance of NPY......Neuropeptide Y (NPY) is a peptide neurotransmitter abundantly expressed in the mammalian retina. Since its discovery, NPY has been studied in retinas of several species, but detailed characterization of morphology, cell-type, and connectivity has never been conducted in larger mammals including...... humans and pigs. As the pig due to size and cellular composition is a well-suited animal for retinal research, we chose to compare the endogenous NPY system of the human retina to that of pigs to support future research in this field. In the present study, using immunohistochemistry, confocal microscopy...

  1. Local flow distribution analysis inside the reactor pools of KALIMER-600 and PDRC performance test facility

    International Nuclear Information System (INIS)

    Jeong, Ji Hwan; Hwang, Seong Won; Choi, Kyeong Sik

    2010-05-01

    In the study, 3-dimensional thermal hydraulic analysis was carried out focusing on the thermal hydraulic behavior inside the reactor pools for both KALIMER-600 and one-fifth scale-down test facility. STAR-CD, one of the commercial CFD codes, was used to analyze 3-dimensional incompressible steady-state thermal hydraulic behavior in both designs of KALIMER-600 and the scale-down test facility. In the KALIMER-600 CFD analysis, the pressure drops in the core and IHX gave a good agreement within 1% error range. It was found that the porous media model was appropriate to analyze the pressure distribution inside reactor core and IHX. Also, a validation analysis showed the pressure drop through the porous media under the condition of 80% flow rate and thermal power was calculated 64% less than in 100% condition giving a physically reasonable analytic result. Since the temperatures in the hot-side pool and cold-side pool were estimated to be very close to 540 and 390 .deg. C specified on the design values respectively, the CFD models of heat source and sink was confirmed. Through the study, the methodology of 3-dimensional CFD analysis about KALIMER-600 has been established and proven. Performed with the methodology, the analysis data such as flow velocity, temperature and pressure distribution were compared by normalizing those data for the actual sized modeling and scale-down modeling. As a result, the characteristics of thermal hydraulic behavior were almost identical for the actual sized modeling and scale-down modeling and the similarity scaling law used in the design of the sodium test facility by KAERI was found to be correct

  2. Distribution of oxytocin and co-localization with arginine vasopressin in the brain of mice.

    Science.gov (United States)

    Otero-García, Marcos; Agustín-Pavón, Carmen; Lanuza, Enrique; Martínez-García, Fernando

    2016-09-01

    Oxytocin (OT) and vasopressin (AVP) play a major role in social behaviours. Mice have become the species of choice for neurobiology of social behaviour due to identification of mouse pheromones and the advantage of genetically modified mice. However, neuroanatomical data on nonapeptidergic systems in mice are fragmentary, especially concerning the central distribution of OT. Therefore, we analyse the immunoreactivity for OT and its neurophysin in the brain of male and female mice (strain CD1). Further, we combine immunofluorescent detection of OT and AVP to locate cells co-expressing both peptides and their putative axonal processes. The results indicate that OT is present in cells of the neurosecretory paraventricular (Pa) and supraoptic hypothalamic nuclei (SON). From the anterior SON, OTergic cells extend into the medial amygdala, where a sparse cell population occupies its ventral anterior and posterior divisions. Co-expression of OT and AVP in these nuclei is rare. Moreover, a remarkable OTergic cell group is found near the ventral bed nucleus of the stria terminalis (BST), distributed between the anterodorsal preoptic nucleus and the nucleus of anterior commissure (ADP/AC). This cell group, the rostral edge of the Pa and the periventricular hypothalamus display frequent OT + AVP double labelling, with a general dominance of OT over AVP immunoreactivity. Fibres with similar immunoreactivity profile innervate the accumbens shell and core, central amygdala and portions of the intervening BST. These data, together with data in the literature on rats, suggest that the projections of ADP/AC nonapeptidergic cells onto these brain centres could promote pup-motivated behaviours and inhibit pup avoidance during motherhood.

  3. Radiation distribution through serpentine concrete using local materials and its application as a reactor biological shield

    International Nuclear Information System (INIS)

    Kansouh, W.A.

    2012-01-01

    Highlights: ► New serpentine concrete was made and examined as a reactor biological shield. ► Ilmenite–limonite concrete is a better reactor biological shield. ► New serpentine concrete is a better reactor fast neutrons shield than ordinary and hematite–serpentine concretes. ► Serpentine concrete has lower properties as a reactor total gamma rays shields. - Abstract: In the present work attempt has been made to estimate the shielding parameters of the new serpentine concrete (density = 2.4 g/cm 3 ) using local materials on the shielding parameters for two types of heat resistant concretes, namely hematite–serpentine (density = 2.5 g/cm 3 ) and ilmenite–limonite (density = 2.9 g/cm 3 ). Shielding parameters for ordinary concrete (density = 2.3 g/cm 3 ) were also discussed. These parameters were determined experimentally for serpentine concrete and compared with previously published values for other concretes, which had also been obtained using local materials. The leakage spectra of reactor fast neutrons and total gamma photon beams from cylindrical samples of these concrete shields were also investigated using a collimated beam from ET-RR-1 reactor. A neutron–gamma spectrometer was used in order to obtain pulse height spectra of reactor fast neutrons and the total gamma rays leakage through the investigated concrete samples. These spectra were utilized to obtain the energy spectra required in these investigations. Removal cross section Σ R (E n ) and linear attenuation coefficient μ(E g ) for reactor fast neutrons and total gamma rays and their relative coefficients were evaluated and presented. Measured results were compared with those previously measured for other concretes. The results show that ilmenite–limonite concrete is a better reactor biological shield than the other three concretes. Serpentine concrete under investigation is a better reactor fast neutrons shield than ordinary and hematite–serpentine concretes. Serpentine concrete

  4. Localization of fugitive methane emission from natural gas distribution network of Titas Gas

    Directory of Open Access Journals (Sweden)

    Mandal Pradip C.

    2017-03-01

    Full Text Available The aim of this paper is to localize the fugitive leaks from the above ground facilities of the existing system of Titas Gas (TG after developing mathematical model for fugitive emission. Soap screening techniques and Gasurveyor 500 series instrument were used in this study for detecting potential leaks. Leaked gas was quantified using either Hi-Flow gas sampler or bagging measurements system. The results show that the respective potential gas leaking point of City Gate Station (CGS, commercial Regulating and Metering Station (RMS, industrial RMS, residential RMS and Town Bordering Station (TBS/ District Regulating Station (DRS are scrubber dump valve (average leak rate 217.00 L/min, insulating point (average leak rate 4.04 L/min, tube fitting connector (average leak rate 8.00 L/min, connector (average leak rate 1.55 L/min and pressure relief valve (average leak rate 437.92 L/min. Fugitive methane emission can be reduced by stopping leaks of fittings or components having high KLeak value.

  5. An Overview: Distribution, Production, and Diversity of Local Landraces of Buckwheat in Nepal

    Directory of Open Access Journals (Sweden)

    Dol Raj Luitel

    2017-01-01

    Full Text Available Buckwheat is a sixth staple food crop after rice, wheat, maize, finger millet, and barley in Nepal. It is considered as an alternate cereal and poor man’s crop, representing an important food supply in remote places of Himalayas. It is the best crop in higher altitude in terms of adaptation to different climatic variables and easily fitted to different cropping patterns due to short duration. It is cultivated on marginal land in 61 out of 75 districts of Nepal from some 60 m to 4500 m asl, especially hilly and mountain districts like Rukum, Rolpa, Jajarkot, Dolpa, Humla, Jumla, Kalikot, Kavre, Dolakha, and Okhaldhunga. Sweet buckwheat varieties are generally grown in midhill and Terai but Tartary buckwheat varieties are grown in higher altitude. There are altogether 19 local landraces of sweat buckwheat and 37 for Tartary buckwheat listed from Nepal. The largest producers are China, USA, and Russia and Japan is principal user of global buckwheat grown in the world. In Nepal, it is cultivated in 10510 ha area with production of 10355 t/yr and yield of 0.983 t/ha. It has also medicinal value used in different forms including all its parts so the demand of buckwheat is increasing.

  6. Distributed 3D Source Localization from 2D DOA Measurements Using Multiple Linear Arrays

    Directory of Open Access Journals (Sweden)

    Antonio Canclini

    2017-01-01

    Full Text Available This manuscript addresses the problem of 3D source localization from direction of arrivals (DOAs in wireless acoustic sensor networks. In this context, multiple sensors measure the DOA of the source, and a central node combines the measurements to yield the source location estimate. Traditional approaches require 3D DOA measurements; that is, each sensor estimates the azimuth and elevation of the source by means of a microphone array, typically in a planar or spherical configuration. The proposed methodology aims at reducing the hardware and computational costs by combining measurements related to 2D DOAs estimated from linear arrays arbitrarily displaced in the 3D space. Each sensor measures the DOA in the plane containing the array and the source. Measurements are then translated into an equivalent planar geometry, in which a set of coplanar equivalent arrays observe the source preserving the original DOAs. This formulation is exploited to define a cost function, whose minimization leads to the source location estimation. An extensive simulation campaign validates the proposed approach and compares its accuracy with state-of-the-art methodologies.

  7. Successfully Changing the Landscape of Information Distribution: Extension Food Website Reaches People Locally and Globally

    Directory of Open Access Journals (Sweden)

    Alice Henneman

    2016-02-01

    Full Text Available The goal of the Food website was to develop Internet-based content that was relevant and reached the general public and multiplier groups, such as educators, health professionals, and media outlets. The purpose of this paper was to examine whether a multi-modal approach to information delivery through increases in and changes to content, electronic mailing list creation, and social media posting impacted user access, traffic channels, and referrals from 2010 to 2014. When comparing 2010-2011 versus 2013-2014, there was a 150% increase in total pageviews, 197% increase in unique pageviews, and a 39% increase in average time spent on a page. Since 2010, the website had over 5.2 million total pageviews, 3.1 million sessions, and 2.6 million users. In 2014, top social media referrals included Pinterest, Facebook, LinkedIn, and Twitter. Age of visitors ranged from 18 to 65+, with 45% being 18-34 years old. Approximately 70% were female. Visitors came from 229 countries/territories and 18,237 different cities. The website connects Nebraska and the world to the exciting food research and information generated at the University of Nebraska-Lincoln and is playing an increasingly important role in shaping the future of food in the local and global community.

  8. Power spectrum tomography of dark matter annihilation with local galaxy distribution

    Energy Technology Data Exchange (ETDEWEB)

    Ando, Shin' ichiro, E-mail: s.ando@uva.nl [GRAPPA Institute, University of Amsterdam, 1098 XH Amsterdam (Netherlands)

    2014-10-01

    Cross-correlating the gamma-ray background with local galaxy catalogs potentially gives stringent constraints on dark matter annihilation. We provide updated theoretical estimates of sensitivities to the annihilation cross section from gamma-ray data with Fermi telescope and 2MASS galaxy catalogs, by elaborating the galaxy power spectrum and astrophysical backgrounds, and adopting the Markov-Chain Monte Carlo simulations. In particular, we show that taking tomographic approach by dividing the galaxy catalogs into more than one redshift slice will improve the sensitivity by a factor of a few to several. If dark matter halos contain lots of bright substructures, yielding a large annihilation boost (e.g., a factor of ∼100 for galaxy-size halos), then one may be able to probe the canonical annihilation cross section for thermal production mechanism up to masses of ∼700 GeV. Even with modest substructure boost (e.g., a factor of ∼10 for galaxy-size halos), on the other hand, the sensitivities could still reach a factor of three larger than the canonical cross section for dark matter masses of tens to a few hundreds of GeV.

  9. New locality of Hymenochaete cruenta in the Olbina nature reserve and revisiting of distribution of this fungus in Poland

    Directory of Open Access Journals (Sweden)

    Marta Brygida Kujawska

    2016-12-01

    Full Text Available Hymenochaete cruenta is a saprotrophic fungus, grown mainly on the bark of dead branches and trunks of Abies trees and thus the distribution of this fungus in Poland and other European countries is closely connected with natural range of silver fir. Despite its wide range, H. cruenta is considered as rare in the whole area of its occurrence. In this paper, we present a new locality of H. cruenta, discovered in May and September 2016 in the Olbina nature reserve (southern Wielkopolska Lowland, Kalisz Forest District. Ecological notes and macro- and microscopic feature of basidiocarps of this fungus are presented. Additionally, the current distribution of H. cruenta in Poland comprising 78 localities is provided. The rank of H. cruenta among threatened species categories in different European countries is discussed. It seems that the species is rare and threatened in Poland, and it should be still classified as “vulnerable” on the red list of macrofungi. The significance of H. cruenta for diversity of mycobiota and the necessity of further research on the dynamic of occurrence of H. cruenta inside and outside of the natural range of A. alba is underlined.

  10. Forward-weighted CADIS method for variance reduction of Monte Carlo calculations of distributions and multiple localized quantities

    International Nuclear Information System (INIS)

    Wagner, J. C.; Blakeman, E. D.; Peplow, D. E.

    2009-01-01

    This paper presents a new hybrid (Monte Carlo/deterministic) method for increasing the efficiency of Monte Carlo calculations of distributions, such as flux or dose rate distributions (e.g., mesh tallies), as well as responses at multiple localized detectors and spectra. This method, referred to as Forward-Weighted CADIS (FW-CADIS), is a variation on the Consistent Adjoint Driven Importance Sampling (CADIS) method, which has been used for some time to very effectively improve the efficiency of Monte Carlo calculations of localized quantities, e.g., flux, dose, or reaction rate at a specific location. The basis of this method is the development of an importance function that represents the importance of particles to the objective of uniform Monte Carlo particle density in the desired tally regions. Implementation of this method utilizes the results from a forward deterministic calculation to develop a forward-weighted source for a deterministic adjoint calculation. The resulting adjoint function is then used to generate consistent space- and energy-dependent source biasing parameters and weight windows that are used in a forward Monte Carlo calculation to obtain approximately uniform statistical uncertainties in the desired tally regions. The FW-CADIS method has been implemented in the ADVANTG/MCNP framework and has been fully automated within the MAVRIC sequence of SCALE 6. Results of the application of the method to enabling the calculation of dose rates throughout an entire full-scale pressurized-water reactor facility are presented and discussed. (authors)

  11. Orthobunyavirus ultrastructure and the curious tripodal glycoprotein spike.

    Directory of Open Access Journals (Sweden)

    Thomas A Bowden

    Full Text Available The genus Orthobunyavirus within the family Bunyaviridae constitutes an expanding group of emerging viruses, which threaten human and animal health. Despite the medical importance, little is known about orthobunyavirus structure, a prerequisite for understanding virus assembly and entry. Here, using electron cryo-tomography, we report the ultrastructure of Bunyamwera virus, the prototypic member of this genus. Whilst Bunyamwera virions are pleomorphic in shape, they display a locally ordered lattice of glycoprotein spikes. Each spike protrudes 18 nm from the viral membrane and becomes disordered upon introduction to an acidic environment. Using sub-tomogram averaging, we derived a three-dimensional model of the trimeric pre-fusion glycoprotein spike to 3-nm resolution. The glycoprotein spike consists mainly of the putative class-II fusion glycoprotein and exhibits a unique tripod-like arrangement. Protein-protein contacts between neighbouring spikes occur at membrane-proximal regions and intra-spike contacts at membrane-distal regions. This trimeric assembly deviates from previously observed fusion glycoprotein arrangements, suggesting a greater than anticipated repertoire of viral fusion glycoprotein oligomerization. Our study provides evidence of a pH-dependent conformational change that occurs during orthobunyaviral entry into host cells and a blueprint for the structure of this group of emerging pathogens.

  12. Localized zinc distribution in shark vertebrae suggests differential deposition during ontogeny and across vertebral structures.

    Science.gov (United States)

    Raoult, Vincent; Howell, Nicholas; Zahra, David; Peddemors, Victor M; Howard, Daryl L; de Jonge, Martin D; Buchan, Benjamin L; Williamson, Jane E

    2018-01-01

    The development of shark vertebrae and the possible drivers of inter- and intra-specific differences in vertebral structure are poorly understood. Shark vertebrae are used to examine life-history traits related to trophic ecology, movement patterns, and the management of fisheries; a better understanding of their development would be beneficial to many fields of research that rely on these calcified structures. This study used Scanning X-ray Fluorescence Microscopy to observe zinc distribution within vertebrae of ten shark species from five different orders. Zinc was mostly localised within the intermedialis and was generally detected at levels an order of magnitude lower in the corpus calcareum. In most species, zinc concentrations were higher pre-birth mark, indicating a high rate of pre-natal zinc deposition. These results suggest there are inter-specific differences in elemental deposition within vertebrae. Since the deposition of zinc is physiologically-driven, these differences suggest that the processes of growth and deposition are potentially different in the intermedialis and corpus calcareum, and that caution should be taken when extrapolating information such as annual growth bands from one structure to the other. Together these results suggest that the high inter-specific variation in vertebral zinc deposition and associated physiologies may explain the varying effectiveness of ageing methodologies applied to elasmobranch vertebrae.

  13. Spatial distribution of limited resources and local density regulation in juvenile Atlantic salmon.

    Science.gov (United States)

    Finstad, Anders G; Einum, Sigurd; Ugedal, Ola; Forseth, Torbjørn

    2009-01-01

    1. Spatial heterogeneity of resources may influence competition among individuals and thus have a fundamental role in shaping population dynamics and carrying capacity. In the present study, we identify shelter opportunities as a limiting resource for juvenile Atlantic salmon (Salmo salar L.). Experimental and field studies are combined in order to demonstrate how the spatial distribution of shelters may influence population dynamics on both within and among population scales. 2. In closed experimental streams, fish performance scaled negatively with decreasing shelter availability and increasing densities. In contrast, the fish in open stream channels dispersed according to shelter availability and performance of fish remaining in the streams did not depend on initial density or shelters. 3. The field study confirmed that spatial variation in densities of 1-year-old juveniles was governed both by initial recruit density and shelter availability. Strength of density-dependent population regulation, measured as carrying capacity, increased with decreasing number of shelters. 4. Nine rivers were surveyed for spatial variation in shelter availability and increased shelter heterogeneity tended to decrease maximum observed population size (measured using catch statistics of adult salmon as a proxy). 5. Our studies highlight the importance of small-scale within-population spatial structure in population dynamics and demonstrate that not only the absolute amount of limiting resources but also their spatial arrangement can be an important factor influencing population carrying capacity.

  14. Traffic and trend analysis of local- and wide-area networks for a distributed PACS implementation

    Science.gov (United States)

    Gac, Robert J., Jr.; Harding, Douglas, Jr.; Weiser, John C.; Chacko, Anna K.; Radvany, Martin; Romlein, John R.

    2000-05-01

    Inductive Modeling Techniques (IMT) in a stand alone, distributed Picture Archiving and Communication System (PACS) or telemedicine environment can be utilized to monitor SNMP (Simple Network Management Protocol) enabled devices such as network switches, servers or workstations. A comprehensive approach using IMT is presented across the stages of the PACS lifecycle: Pre-PACS, Implementation, and Clinical Use. At each stage of the cycle, the results of IMT can be utilized to assist in assessing and forecasting future system loading. This loading represents a clinical trend analysis equating to the clinical workflow and delivery of services. Specific attention is directed to an understanding and thorough depiction of IMT methodology, focusing on the use of SNMP, the Management Information Base (MIB), and the data stream output that is mapped and placed in an object-oriented database and made available for web-based, real time, in-depth viewing and/or analysis. A thorough description of these outputs is presented, spotlighting potential report applications such as system failures; existing system, CPU, workstation, server and LAN/WAN link utilization; packet rates; application isolation; notification of system alarms; fault isolation; high/low bandwidth users; and data transfer rates. These types of data are increasingly required for programming LAN/WAN upgrades as digital imaging and PACS are implemented.

  15. Localized zinc distribution in shark vertebrae suggests differential deposition during ontogeny and across vertebral structures.

    Directory of Open Access Journals (Sweden)

    Vincent Raoult

    Full Text Available The development of shark vertebrae and the possible drivers of inter- and intra-specific differences in vertebral structure are poorly understood. Shark vertebrae are used to examine life-history traits related to trophic ecology, movement patterns, and the management of fisheries; a better understanding of their development would be beneficial to many fields of research that rely on these calcified structures. This study used Scanning X-ray Fluorescence Microscopy to observe zinc distribution within vertebrae of ten shark species from five different orders. Zinc was mostly localised within the intermedialis and was generally detected at levels an order of magnitude lower in the corpus calcareum. In most species, zinc concentrations were higher pre-birth mark, indicating a high rate of pre-natal zinc deposition. These results suggest there are inter-specific differences in elemental deposition within vertebrae. Since the deposition of zinc is physiologically-driven, these differences suggest that the processes of growth and deposition are potentially different in the intermedialis and corpus calcareum, and that caution should be taken when extrapolating information such as annual growth bands from one structure to the other. Together these results suggest that the high inter-specific variation in vertebral zinc deposition and associated physiologies may explain the varying effectiveness of ageing methodologies applied to elasmobranch vertebrae.

  16. Systemic distribution, subcellular localization and differential expression of sphingosine-1-phosphate receptors in benign and malignant human tissues.

    Science.gov (United States)

    Wang, Chunyi; Mao, Jinghe; Redfield, Samantha; Mo, Yinyuan; Lage, Janice M; Zhou, Xinchun

    2014-10-01

    Five sphingosine-1-phosphate receptors (S1PR): S1PR1, S1PR2, S1PR3, S1PR4 and S1PR5 (S1PR1-5) have been shown to be involved in the proliferation and progression of various cancers. However, none of the S1PRs have been systemically investigated. In this study, we performed immunohistochemistry (IHC) for S1PR1-S1PR5 on different tissues, in order to simultaneously determine the systemic distribution, subcellular localization and expression level of all five S1PRs. We constructed tissue microarrays (TMAs) from 384 formalin-fixed paraffin-embedded (FFPE) blocks containing 183 benign and 201 malignant tissues from 34 human organs/systems. Then we performed IHC for all five S1PRs simultaneously on these TMA slides. The distribution, subcellular localization and expression of each S1PR were determined for each tissue. The data in benign and malignant tissues from the same organ/tissue were then compared using the Student's t-test. In order to reconfirm the subcellular localization of each S1PR as determined by IHC, immunocytochemistry (ICC) was performed on several malignant cell lines. We found that all five S1PRs are widely distributed in multiple human organs/systems. All S1PRs are expressed in both the cytoplasm and nucleus, except S1PR3, whose IHC signals are only seen in the nucleus. Interestingly, the S1PRs are rarely expressed on cellular membranes. Each S1PR is unique in its organ distribution, subcellular localization and expression level in benign and malignant tissues. Among the five S1PRs, S1PR5 has the highest expression level (in either the nucleus or cytoplasm), with S1PR1, 3, 2 and 4 following in descending order. Strong nuclear expression was seen for S1PR1, S1PR3 and S1PR5, whereas S1PR2 and S1PR4 show only weak staining. Four organs/tissues (adrenal gland, liver, brain and colon) show significant differences in IHC scores for the multiple S1PRs (nuclear and/or cytoplasmic), nine (stomach, lymphoid tissues, lung, ovary, cervix, pancreas, skin, soft

  17. NHE3 in an ancestral vertebrate: primary sequence, distribution, localization, and function in gills.

    Science.gov (United States)

    Choe, Keith P; Kato, Akira; Hirose, Shigehisa; Plata, Consuelo; Sindic, Aleksandra; Romero, Michael F; Claiborne, J B; Evans, David H

    2005-11-01

    In mammals, the Na+/H+ exchanger 3 (NHE3) is expressed with Na+/K+-ATPase in renal proximal tubules, where it secretes H+ and absorbs Na+ to maintain blood pH and volume. In elasmobranchs (sharks, skates, and stingrays), the gills are the dominant site of pH and osmoregulation. This study was conducted to determine whether epithelial NHE homologs exist in elasmobranchs and, if so, to localize their expression in gills and determine whether their expression is altered by environmental salinity or hypercapnia. Degenerate primers and RT-PCR were used to deduce partial sequences of mammalian NHE2 and NHE3 homologs from the gills of the euryhaline Atlantic stingray (Dasyatis sabina). Real-time PCR was then used to demonstrate that mRNA expression of the NHE3 homolog increased when stingrays were transferred to low salinities but not during hypercapnia. Expression of the NHE2 homolog did not change with either treatment. Rapid amplification of cDNA was then used to deduce the complete sequence of a putative NHE3. The 2,744-base pair cDNA includes a coding region for a 2,511-amino acid protein that is 70% identical to human NHE3 (SLC9A3). Antisera generated against the carboxyl tail of the putative stingray NHE3 labeled the apical membranes of Na+/K+-ATPase-rich epithelial cells, and acclimation to freshwater caused a redistribution of labeling in the gills. This study provides the first NHE3 cloned from an elasmobranch and is the first to demonstrate an increase in gill NHE3 expression during acclimation to low salinities, suggesting that NHE3 can absorb Na+ from ion-poor environments.

  18. Linear distributed source modeling of local field potentials recorded with intra-cortical electrode arrays.

    Directory of Open Access Journals (Sweden)

    Rikkert Hindriks

    Full Text Available Planar intra-cortical electrode (Utah arrays provide a unique window into the spatial organization of cortical activity. Reconstruction of the current source density (CSD underlying such recordings, however, requires "inverting" Poisson's equation. For inter-laminar recordings, this is commonly done by the CSD method, which consists in taking the second-order spatial derivative of the recorded local field potentials (LFPs. Although the CSD method has been tremendously successful in mapping the current generators underlying inter-laminar LFPs, its application to planar recordings is more challenging. While for inter-laminar recordings the CSD method seems reasonably robust against violations of its assumptions, is it unclear as to what extent this holds for planar recordings. One of the objectives of this study is to characterize the conditions under which the CSD method can be successfully applied to Utah array data. Using forward modeling, we find that for spatially coherent CSDs, the CSD method yields inaccurate reconstructions due to volume-conducted contamination from currents in deeper cortical layers. An alternative approach is to "invert" a constructed forward model. The advantage of this approach is that any a priori knowledge about the geometrical and electrical properties of the tissue can be taken into account. Although several inverse methods have been proposed for LFP data, the applicability of existing electroencephalographic (EEG and magnetoencephalographic (MEG inverse methods to LFP data is largely unexplored. Another objective of our study therefore, is to assess the applicability of the most commonly used EEG/MEG inverse methods to Utah array data. Our main conclusion is that these inverse methods provide more accurate CSD reconstructions than the CSD method. We illustrate the inverse methods using event-related potentials recorded from primary visual cortex of a macaque monkey during a motion discrimination task.

  19. A local energy management of a hybrid PV-storage based distributed generation for microgrids

    International Nuclear Information System (INIS)

    Choudar, Adel; Boukhetala, Djamel; Barkat, Said; Brucker, Jean-Michel

    2015-01-01

    Highlights: • The proposed system is based on photovoltaic system, batteries and ultra-capacitors. • Batteries are used as an energy source, ultra-capacitors are used as a fast power regulator. • An energy management strategy, to operate a grid connected active PV system (APS). • Different levels of the control system are studied and organized in a hierarchical control structure. • Different operating modes are explained (island, limited PV power, normal, fast recovering). - Abstract: The presented work focuses on energy management strategy, to operate a grid connected active PV system (APS) in a microgrid. A microgrid is a smart grid in a small scale which can be stand-alone or grid-tied. The proposed system is based on photovoltaic system, batteries and ultra-capacitors. Three converters are used to interface the elements of the APS to a common DC-link capacitor. The presented control strategy manages the power flow between the converters and the grid through the DC-link in order to maintain the grid power demand coming from the grid operator. Batteries are used as an energy source, to stabilize and permit the APS units to run at a constant and stable output power, damping peak surges in electricity demand and to store the excess of energy from the PV array. Ultra-capacitors are used as a fast power regulator to: limit the battery’s current, regulate the DC-link voltage when the disconnection mode occurs and to deliver a smooth power to the grid, despite primary source and load fluctuations. Several operating modes are presented to manage locally the power flows between the various sources, taking into account the state of charge of batteries (SOC), the energy level of ultra-capacitors (Lev), the available PV power and the power demand from the grid operator

  20. [Distribution patterns of canopy and understory tree species at local scale in a Tierra Firme forest, the Colombian Amazonia].

    Science.gov (United States)

    Barreto-Silva, Juan Sebastian; López, Dairon Cárdenas; Montoya, Alvaro Javier Duque

    2014-03-01

    The effect of environmental variation on the structure of tree communities in tropical forests is still under debate. There is evidence that in landscapes like Tierra Firme forest, where the environmental gradient decreases at a local level, the effect of soil on the distribution patterns of plant species is minimal, happens to be random or is due to biological processes. In contrast, in studies with different kinds of plants from tropical forests, a greater effect on floristic composition of varying soil and topography has been reported. To assess this, the current study was carried out in a permanent plot of ten hectares in the Amacayacu National Park, Colombian Amazonia. To run the analysis, floristic and environmental variations were obtained according to tree species abundance categories and growth forms. In order to quantify the role played by both environmental filtering and dispersal limitation, the variation of the spatial configuration was included. We used Detrended Correspondence Analysis and Canonical Correspondence Analysis, followed by a variation partitioning, to analyze the species distribution patterns. The spatial template was evaluated using the Principal Coordinates of Neighbor Matrix method. We recorded 14 074 individuals from 1 053 species and 80 families. The most abundant families were Myristicaceae, Moraceae, Meliaceae, Arecaceae and Lecythidaceae, coinciding with other studies from Northwest Amazonia. Beta diversity was relatively low within the plot. Soils were very poor, had high aluminum concentration and were predominantly clayey. The floristic differences explained along the ten hectares plot were mainly associated to biological processes, such as dispersal limitation. The largest proportion of community variation in our dataset was unexplained by either environmental or spatial data. In conclusion, these results support random processes as the major drivers of the spatial variation of tree species at a local scale on Tierra Firme

  1. An ESPRIT-Based Approach for 2-D Localization of Incoherently Distributed Sources in Massive MIMO Systems

    Science.gov (United States)

    Hu, Anzhong; Lv, Tiejun; Gao, Hui; Zhang, Zhang; Yang, Shaoshi

    2014-10-01

    In this paper, an approach of estimating signal parameters via rotational invariance technique (ESPRIT) is proposed for two-dimensional (2-D) localization of incoherently distributed (ID) sources in large-scale/massive multiple-input multiple-output (MIMO) systems. The traditional ESPRIT-based methods are valid only for one-dimensional (1-D) localization of the ID sources. By contrast, in the proposed approach the signal subspace is constructed for estimating the nominal azimuth and elevation direction-of-arrivals and the angular spreads. The proposed estimator enjoys closed-form expressions and hence it bypasses the searching over the entire feasible field. Therefore, it imposes significantly lower computational complexity than the conventional 2-D estimation approaches. Our analysis shows that the estimation performance of the proposed approach improves when the large-scale/massive MIMO systems are employed. The approximate Cram\\'{e}r-Rao bound of the proposed estimator for the 2-D localization is also derived. Numerical results demonstrate that albeit the proposed estimation method is comparable with the traditional 2-D estimators in terms of performance, it benefits from a remarkably lower computational complexity.

  2. Micromechanical analysis of martensite distribution on strain localization in dual phase steels by scanning electron microscopy and crystal plasticity simulation

    Energy Technology Data Exchange (ETDEWEB)

    Jafari, M. [Department of Mechanical Engineering, Isfahan University of Technology, Isfahan (Iran, Islamic Republic of); Ziaei-Rad, S., E-mail: szrad@cc.iut.ac.ir [Department of Mechanical Engineering, Isfahan University of Technology, Isfahan (Iran, Islamic Republic of); Saeidi, N. [Department of Materials Engineering, Isfahan University of Technology, Isfahan (Iran, Islamic Republic of); Jamshidian, M. [Department of Mechanical Engineering, Isfahan University of Technology, Isfahan (Iran, Islamic Republic of)

    2016-07-18

    The morphology and distribution of the dispersed martensite islands in the ferrite matrix plays a key role in the formation of shear bands in dual phase steels. In this study, we investigate the relationship between the martensite dispersion and the strain localization regions due to the formation of shear bands in fine-grained DP 780 steel, employing experimental observations as well as numerical simulations. SEM studies of the deformed microstructure showed that voids nucleated at ferrite-martensite interface within larger ferrite grains and regions with low local martensite fraction. The experimental results were precisely analyzed by finite element simulations based on the theory of crystal plasticity. A parametric study was then performed to obtain a deeper insight in to the effect of martensite dispersion on the strain localization of the neighboring ferrite. Crystal plasticity simulation results revealed that in a more regular structure compared to a random structure, a greater region of the ferrite phase contributes to accommodate plasticity. In addition, these regions limit the formation of main shear bands by creating barriers against stress concentration regions, results in lower growth and interaction of stress concentration regions with each others.

  3. Distribution of C-myc Antisense Oligonucleotides in Rabbits after Local Delivery by Implanted Gelatin Coated Piatinium -iridium Stent

    Institute of Scientific and Technical Information of China (English)

    张新霞; 庞志功; 崔长琮; 许香广; 胡雪松; 方卫华

    2003-01-01

    Objectives To assess the feasibility, efficiency and tissue distribution of localdelivered c - myc antisense oligonucleotides (ASODN)by implanted gelatin coated Platinium- Iridium (Pt-Ir) stent. Methods Gelatin coated Pt- Ir stentwhich absorbed carboxyfluorescein - 5 - succimidylester (FAM) labeled c -myc ASODN were implantedin the right carotid arteries of 6 rabbits under vision.Blood samples were collected at the indicated times.The target artery、 left carotid artery、 heart、 liver andkidney obtained at 45 minutes、 2 hours and 6hours. The concentration of c - myc ASODN in plasmaand tissues were determined by Thin Layer Fluorome-try. Tissue distribution of c- myc ASODN were as-sessed by fluorescence microscopy. Results At 45min, 2 h, 6 h, the concentration of FAM labeled c -myc ASODN in target artery was 244.39, 194.44,126.94(μg/g tissues) respectively, and the deliveryefficiency were 44.4% 、 35.4% and 23.1% respec-tively. At the same indicated time point, the plasmaconcentration was 8.41, 5. 83, 14.75 (μg/ml) respec-tively. Therefore c -myc ASODN concentrations in thetarget vessel were 29、 33 and 9 -fold higher than thatin the plasma. There was circumferential distribution oflabeled c -myc in the area of highest fluorescein co-inciding with the site of medial dissecting from stent-ing, and the label was most intense in target vesselmedia harvested at 45 min time point and then dis-persed to adventitia. Conclusions Gelatin coated Pt- Ir stent mediated local delivery of c - myc ASODN isfeasible and efficient. The localization of ASODN ismainly in target vessel wall.

  4. A hybrid downscaling procedure for estimating the vertical distribution of ambient temperature in local scale

    Science.gov (United States)

    Yiannikopoulou, I.; Philippopoulos, K.; Deligiorgi, D.

    2012-04-01

    The vertical thermal structure of the atmosphere is defined by a combination of dynamic and radiation transfer processes and plays an important role in describing the meteorological conditions at local scales. The scope of this work is to develop and quantify the predictive ability of a hybrid dynamic-statistical downscaling procedure to estimate the vertical profile of ambient temperature at finer spatial scales. The study focuses on the warm period of the year (June - August) and the method is applied to an urban coastal site (Hellinikon), located in eastern Mediterranean. The two-step methodology initially involves the dynamic downscaling of coarse resolution climate data via the RegCM4.0 regional climate model and subsequently the statistical downscaling of the modeled outputs by developing and training site-specific artificial neural networks (ANN). The 2.5ox2.5o gridded NCEP-DOE Reanalysis 2 dataset is used as initial and boundary conditions for the dynamic downscaling element of the methodology, which enhances the regional representivity of the dataset to 20km and provides modeled fields in 18 vertical levels. The regional climate modeling results are compared versus the upper-air Hellinikon radiosonde observations and the mean absolute error (MAE) is calculated between the four grid point values nearest to the station and the ambient temperature at the standard and significant pressure levels. The statistical downscaling element of the methodology consists of an ensemble of ANN models, one for each pressure level, which are trained separately and employ the regional scale RegCM4.0 output. The ANN models are theoretically capable of estimating any measurable input-output function to any desired degree of accuracy. In this study they are used as non-linear function approximators for identifying the relationship between a number of predictor variables and the ambient temperature at the various vertical levels. An insight of the statistically derived input

  5. Spectral narrowing and spin echo for localized carriers with heavy-tailed L evy distribution of hopping times

    Energy Technology Data Exchange (ETDEWEB)

    Yue, Z. [Univ. of Utah, Salt Lake City, UT (United States); Mkhitaryan, Vagharsh [Ames Lab. and Iowa State Univ., Ames, IA (United States); Raikh, M. E. [Univ. of Utah, Salt Lake City, UT (United States)

    2016-02-02

    We study analytically the free induction decay and the spin echo decay originating from the localized carriers moving between the sites which host random magnetic fields. Due to disorder in the site positions and energies, the on-site residence times, , are widely spread according to the L evy distribution. The power-law tail ∝ τ-1-∝ in the distribution of does not affect the conventional spectral narrowing for α > 2, but leads to a dramatic acceleration of the free induction decay in the domain 2 > α > 1. The next abrupt acceleration of the decay takes place as becomes smaller than 1. In the latter domain the decay does not follow a simple-exponent law. To capture the behavior of the average spin in this domain, we solve the evolution equation for the average spin using the approach different from the conventional approach based on the Laplace transform. Unlike the free induction decay, the tail in the distribution of the residence times leads to the slow decay of the spin echo. The echo is dominated by realizations of the carrier motion for which the number of sites, visited by the carrier, is minimal.

  6. Seeding method influences warm-season grass abundance and distribution but not local diversity in grassland restoration

    Science.gov (United States)

    Yurkonis, Kathryn A.; Wilsey, Brian J.; Moloney, Kirk A.; Drobney, Pauline; Larson, Diane L.

    2010-01-01

    Ecological theory predicts that the arrangement of seedlings in newly restored communities may influence future species diversity and composition. We test the prediction that smaller distances between neighboring seeds in drill seeded grassland plantings would result in lower species diversity, greater weed abundance, and larger conspecific patch sizes than otherwise similar broadcast seeded plantings. A diverse grassland seed mix was either drill seeded, which places seeds in equally spaced rows, or broadcast seeded, which spreads seeds across the ground surface, into 24 plots in each of three sites in 2005. In summer 2007, we measured species abundance in a 1 m2 quadrat in each plot and mapped common species within the quadrat by recording the most abundant species in each of 64 cells. Quadrat-scale diversity and weed abundance were similar between drilled and broadcast plots, suggesting that processes that limited establishment and controlled invasion were not affected by such fine-scale seed distribution. However, native warm-season (C4) grasses were more abundant and occurred in less compact patches in drilled plots. This difference in C4 grass abundance and distribution may result from increased germination or vegetative propagation of C4 grasses in drilled plots. Our findings suggest that local plant density may control fine-scale heterogeneity and species composition in restored grasslands, processes that need to be further investigated to determine whether seed distributions can be manipulated to increase diversity in restored grasslands.

  7. Comparison of pigment cell ultrastructure and organisation in the dermis of marble trout and brown trout, and first description of erythrophore ultrastructure in salmonids.

    Science.gov (United States)

    Djurdjevič, Ida; Kreft, Mateja Erdani; Sušnik Bajec, Simona

    2015-11-01

    Skin pigmentation in animals is an important trait with many functions. The present study focused on two closely related salmonid species, marble trout (Salmo marmoratus) and brown trout (S. trutta), which display an uncommon labyrinthine (marble-like) and spot skin pattern, respectively. To determine the role of chromatophore type in the different formation of skin pigment patterns in the two species, the distribution and ultrastructure of chromatophores was examined with light microscopy and transmission electron microscopy. The presence of three types of chromatophores in trout skin was confirmed: melanophores; xanthophores; and iridophores. In addition, using correlative microscopy, erythrophore ultrastructure in salmonids was described for the first time. Two types of erythrophores are distinguished, both located exclusively in the skin of brown trout: type 1 in black spot skin sections similar to xanthophores; and type 2 with a unique ultrastructure, located only in red spot skin sections. Morphologically, the difference between the light and dark pigmentation of trout skin depends primarily on the position and density of melanophores, in the dark region covering other chromatophores, and in the light region with the iridophores and xanthophores usually exposed. With larger amounts of melanophores, absence of xanthophores and presence of erythrophores type 1 and type L iridophores in the black spot compared with the light regions and the presence of erythrophores type 2 in the red spot, a higher level of pigment cell organisation in the skin of brown trout compared with that of marble trout was demonstrated. Even though the skin regions with chromatophores were well defined, not all the chromatophores were in direct contact, either homophilically or heterophilically, with each other. In addition to short-range interactions, an important role of the cellular environment and long-range interactions between chromatophores in promoting adult pigment pattern

  8. Towards A Complete Census of Compton-thick AGN and N_H Distribution in the Local Universe

    Science.gov (United States)

    Annuar, A.; Gandhi, P.; Alexander, D.; Asmus, D.; Goulding, A.; Harrison, C.; Lansbury, G.

    2014-07-01

    Many studies have shown that Compton-thick AGNs (CTAGNs) provide important contribution to the cosmic X-ray background spectrum (˜25% at 20keV). They are expected to dominate the Seyfert 2 population in the local universe, yet only ˜20 bona fide CTAGNs are known. We present an updated census of CTAGN population in the local universe using a volume-limited AGN sample complete to D=15Mpc. Intrinsic relations between 2-10keV X-ray luminosity and mid-IR emission at 12μm, [OIV]λ25.68μm and [NeV]λ14.32μm are investigated, and it is found that the emission at 12μm has the tightest correlation with the X-ray luminosity.Candidates for CTAGN are then selected using this relation and by comparing their 12μm luminosity with the observed X-ray luminosity.We also investigate the Compton-thick nature of these sources using the optical [OIII]λ5007{A}:X-ray diagnostic for comparison, and find that 35-50% of the sample are Compton-thick,of which 10-20% would be missed with the optical approach.Finally, we estimate the intrinsic N_{H} distribution of AGN population in the local universe from this analysis, and show that up to 70% of the sources are heavily obscured (N_{H}>10^{23} cm^{-2}), with ≥50% lying in the Compton-thick regime (N_{H}>10^{24} cm^{-2}).This work provides a well-defined local benchmark for AGN obscuration studies.

  9. Balanites aegyptiaca (L. Delile: geographical distribution and ethnobotanical knowledge by local populations in the Ferlo (north Senegal

    Directory of Open Access Journals (Sweden)

    Sagna, MB.

    2014-01-01

    Full Text Available Balanites aegyptiaca (L. Delile is a species of tropical flora for which the variety aegyptiaca is adapted to Sahelian climate. The species is among those chosen for the restoration of Sahelian ecosystems in the context of the pan-African reforestation project, the Great Green Wall for the Sahara and Sahel Initiative (GGW. This study redefines the distribution range and its ecology and studies its uses in the Ferlo region in the north of Senegal using surveys carried out among the local population. The eco-geographical study shows that the species occupies several Sahel-Saharan regions of Africa and the Middle East. With broad ecological amplitude, it is very resistant to drought and relatively indifferent to the type of soil. Results of the ethno-botanical survey show that local people in the Ferlo region have a wealth of knowledge and expertise on B. aegyptiaca. These surveys also revealed the extent to which local populations rely on the tree for food, fodder, construction and medicine. The fruit and wood are the most highly prized parts of the tree, with the greatest use of the fruit in people's diets. In medicinal terms, B. aegyptiaca is used to treat several affections. Marketing the fruits could be of socio-economic interest for local people, and in particular, for women. This study is particularly opportune since B. aegyptiaca var. aegyptiaca is currently being planted in large numbers within the Great Green Wall for the Sahara and the Sahel Initiative (GGW. It also provides information that could help in better management of this natural resource, adapted both to the hostile Sahelian climate and of great use to Mankind.

  10. Organization of cytokeratin cytoskeleton and germ plasm in the vegetal cortex of Xenopus laevis oocytes depends on coding and non-coding RNAs: Three-dimensional and ultrastructural analysis

    International Nuclear Information System (INIS)

    Kloc, Malgorzata; Bilinski, Szczepan; Dougherty, Matthew T.

    2007-01-01

    Recent studies discovered a novel structural role of RNA in maintaining the integrity of the mitotic spindle and cellular cytoskeleton. In Xenopus laevis, non-coding Xlsirts and coding VegT RNAs play a structural role in anchoring localized RNAs, maintaining the organization of the cytokeratin cytoskeleton and germinal granules in the oocyte vegetal cortex and in subsequent development of the germline in the embryo. We studied the ultrastructural effects of antisense oligonucleotide driven ablation of Xlsirts and VegT RNAs on the organization of the cytokeratin, germ plasm and other components of the vegetal cortex. We developed a novel method to immunolabel and visualize cytokeratin at the electron microscopy level, which allowed us to reconstruct the ultrastructural organization of the cytokeratin network relative to the components of the vegetal cortex in Xenopus oocytes. The removal of Xlsirts and VegT RNAs not only disrupts the cytokeratin cytoskeleton but also has a profound transcript-specific effect on the anchoring and distribution of germ plasm islands and their germinal granules and the arrangement of yolk platelets within the vegetal cortex. We suggest that the cytokeratin cytoskeleton plays a role in anchoring of germ plasm islands within the vegetal cortex and germinal granules within the germ plasm islands

  11. The local distribution of radiation quality of a collimated fast neutron beam from 15 MeV deuterons on beryllium

    International Nuclear Information System (INIS)

    Fidorra, J.; Booz, J.

    1978-01-01

    The local distribution of radiation quality (ysub(F), ysub(D)) of a collimated fast neutron beam from 14 MeV deuterons on Beryllium was studied with a spherical 1/2 inch EG and G proportional counter simulating a diameter of 2μm. The deuterons were accelerated by the compact cyclotron CV-28 of the Kernforschungsanlage Juelich. The collimator was constructed by the Cyclotron Corporation. The mean neutron energy was 6 MeV. The measurements were performed in air and in a water phantom at a target skin distance of 125 cm. The energy deposition spectra of fast neutrons obtained at various positions were separated into three components of different radiation quality: the gamma component, the recoil proton component, and the heavy ion component

  12. The Regional and Local Distribution of Funds Allocated by the European Agricultural Fund for Rural Development in Romania

    Directory of Open Access Journals (Sweden)

    ALINA-MIRELA MARCU

    2013-01-01

    Full Text Available The objective of this study is to present and analyze the regional and local distribution of the funds allocated by the European Agricultural Fund for Rural Development (EAFRD, European fund that finances rural development in Romania, in the post-accession period. This financing instrument was created by the European Union with the order to continue the main directions of investment of Special Pre-Accession Programme for Agriculture and Rural Development (SAPARD. As a member state of the European Union, Romania observes the principles of the Common Agricultural Policy (CAP while the development of the Romanian rural area for the programming period 2007-2013 is supported by the European Community through the National Rural Development Programme (RDP. This approach pays special attention to improving the quality of life in rural areas and the diversification of the rural economy because local communities in Romania have experienced some changes in this period, while accessing EAFRD funds contributed to increased regional disparities between developed and poor areas.

  13. Ultrastructural studies of synthetic apatite crystals.

    Science.gov (United States)

    Arends, J; Jongebloed, W L

    1979-03-01

    In this paper a survey is given of some ultrastructural properties of synthetic hydroxyapatite. The preparation method by which single crystals with a length in the range of 0.1-3.0mm and a defined purity and stoïchiometry can be produced is given. Two groups of materials are considered in detail: carbonate-rich (greater than 0.1% CO3) and low-carbonate hydroxyapatites. The experiments on carbonate-rich material, being the most interesting from a biological point of view, show that acids attack at an active site in the hexagonal basal-plane of the crystals. Later on the crystals dissolve in the center of the crystal parallel to the c-axis forming tube-like structures. The active site can be protected from dissolution if the crystals are pretreated by EHDP or MFP. A comparison with lattice defect theory shows that most likely dislocations of the "hollow-core" type are responsible for the preferential dissolution.

  14. Ultrastructural Characterization of Zika Virus Replication Factories

    Directory of Open Access Journals (Sweden)

    Mirko Cortese

    2017-02-01

    Full Text Available Summary: A global concern has emerged with the pandemic spread of Zika virus (ZIKV infections that can cause severe neurological symptoms in adults and newborns. ZIKV is a positive-strand RNA virus replicating in virus-induced membranous replication factories (RFs. Here we used various imaging techniques to investigate the ultrastructural details of ZIKV RFs and their relationship with host cell organelles. Analyses of human hepatic cells and neural progenitor cells infected with ZIKV revealed endoplasmic reticulum (ER membrane invaginations containing pore-like openings toward the cytosol, reminiscent to RFs in Dengue virus-infected cells. Both the MR766 African strain and the H/PF/2013 Asian strain, the latter linked to neurological diseases, induce RFs of similar architecture. Importantly, ZIKV infection causes a drastic reorganization of microtubules and intermediate filaments forming cage-like structures surrounding the viral RF. Consistently, ZIKV replication is suppressed by cytoskeleton-targeting drugs. Thus, ZIKV RFs are tightly linked to rearrangements of the host cell cytoskeleton. : Cortese et al. show that ZIKV infection in both human hepatoma and neuronal progenitor cells induces drastic structural modification of the cellular architecture. Microtubules and intermediate filaments surround the viral replication factory composed of vesicles corresponding to ER membrane invagination toward the ER lumen. Importantly, alteration of microtubule flexibility impairs ZIKV replication. Keywords: Zika virus, flavivirus, human neural progenitor cells, replication factories, replication organelles, microtubules, intermediate filaments, electron microscopy, electron tomography, live-cell imaging

  15. Local influence of south-east France topography and land cover on the distribution and characteristics of intense rainfall cells

    Science.gov (United States)

    Renard, Florent

    2017-04-01

    The Greater Lyon area is strongly built up, grouping 58 communes and a population of 1.3 million in approximately 500 km2. The flood risk is high as the territory is crossed by two large watercourses and by streams with torrential flow. Floods may also occur in case of runoff after heavy rain or because of a rise in the groundwater level. The whole territory can therefore be affected, and it is necessary to possess in-depth knowledge of the depths, causes and consequences of rainfall to achieve better management of precipitation in urban areas and to reduce flood risk. This study is thus focused on the effects of topography and land cover on the occurrence, intensity and area of intense rainfall cells. They are identified by local radar meteorology (C-band) combined with a processing algorithm running in a geographic information system (GIS) which identified 109,979 weighted mean centres of them in a sample composed of the five most intense rainfall events from 2001 to 2005. First, analysis of spatial distribution at an overall scale is performed, completed by study at a more detailed scale. The results show that the distribution of high-intensity rainfall cells is spread in cluster form. Subsequently, comparison of intense rainfall cells with the topography shows that cell density is closely linked with land slope but that, above all, urbanised zones feature nearly twice as many rainfall cells as farm land or forest, with more intense intensity.

  16. Predicting local distributions of erosion-corrosion wear sites for the piping in the nuclear power plant using CFD models

    International Nuclear Information System (INIS)

    Ferng, Y.M.

    2008-01-01

    The erosion-corrosion (E/C) wear is an essential degradation mechanism for the piping in the nuclear power plant, which results in the oxide mass loss from the inside of piping, the wall thinning, and even the pipe break. The pipe break induced by the E/C wear may cause costly plant repairs and personal injures. The measurement of pipe wall thickness is a useful tool for the power plant to prevent this incident. In this paper, CFD models are proposed to predict the local distributions of E/C wear sites, which include both the two-phase hydrodynamic model and the E/C models. The impacts of centrifugal and gravitational forces on the liquid droplet behaviors within the piping can be reasonably captured by the two-phase model. Coupled with these calculated flow characteristics, the E/C models can predicted the wear site distributions that show satisfactory agreement with the plant measurements. Therefore, the models proposed herein can assist in the pipe wall monitoring program for the nuclear power plant by way of concentrating the measuring point on the possible sites of severe E/C wear for the piping and reducing the measurement labor works

  17. First-Principles Momentum Dependent Local Ansatz Approach to the Momentum Distribution Function in Iron-Group Transition Metals

    Science.gov (United States)

    Kakehashi, Yoshiro; Chandra, Sumal

    2017-03-01

    The momentum distribution function (MDF) bands of iron-group transition metals from Sc to Cu have been investigated on the basis of the first-principles momentum dependent local ansatz wavefunction method. It is found that the MDF for d electrons show a strong momentum dependence and a large deviation from the Fermi-Dirac distribution function along high-symmetry lines of the first Brillouin zone, while the sp electrons behave as independent electrons. In particular, the deviation in bcc Fe (fcc Ni) is shown to be enhanced by the narrow eg (t2g) bands with flat dispersion in the vicinity of the Fermi level. Mass enhancement factors (MEF) calculated from the jump on the Fermi surface are also shown to be momentum dependent. Large mass enhancements of Mn and Fe are found to be caused by spin fluctuations due to d electrons, while that for Ni is mainly caused by charge fluctuations. Calculated MEF are consistent with electronic specific heat data as well as recent angle resolved photoemission spectroscopy data.

  18. Pattern recognition in spaces of probability distributions for the analysis of edge-localized modes in tokamak plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Shabbir, Aqsa

    2016-07-07

    In this doctoral work, pattern recognition techniques are developed and applied to data from tokamak plasmas, in order to contribute to a systematic analysis of edge-localized modes (ELMs). We employ probabilistic models for a quantitative data description geared towards an enhanced systematization of ELM phenomenology. Hence, we start from the point of view that the fundamental object resulting from the observation of a system is a probability distribution, with every single measurement providing a sample from this distribution. In exploring the patterns emerging from the various ELM regimes and relations, we need methods that can handle the intrinsic probabilistic nature of the data. The original contributions of this work are twofold. First, several novel pattern recognition methods in non-Euclidean spaces of probability distribution functions (PDFs) are developed and validated. The second main contribution lies in the application of these and other techniques to a systematic analysis of ELMs in tokamak plasmas. In regard to the methodological aims of the work, we employ the framework of information geometry to develop pattern visualization and classification methods in spaces of probability distributions. In information geometry, a family of probability distributions is considered as a Riemannian manifold. Every point on the manifold represents a single PDF and the distribution parameters provide local coordinates on the manifold. The Fisher information plays the role of a Riemannian metric tensor, enabling calculation of geodesic curves on the surface. The length of such curves yields the geodesic distance (GD) on probabilistic manifolds, which is a natural similarity (distance) measure between PDFs. Equipped with a suitable distance measure, we extrapolate several distance-based pattern recognition methods to the manifold setting. This includes k-nearest neighbor (kNN) and conformal predictor (CP) methods for classification, as well as multidimensional

  19. Pattern recognition in spaces of probability distributions for the analysis of edge-localized modes in tokamak plasmas

    International Nuclear Information System (INIS)

    Shabbir, Aqsa

    2016-01-01

    In this doctoral work, pattern recognition techniques are developed and applied to data from tokamak plasmas, in order to contribute to a systematic analysis of edge-localized modes (ELMs). We employ probabilistic models for a quantitative data description geared towards an enhanced systematization of ELM phenomenology. Hence, we start from the point of view that the fundamental object resulting from the observation of a system is a probability distribution, with every single measurement providing a sample from this distribution. In exploring the patterns emerging from the various ELM regimes and relations, we need methods that can handle the intrinsic probabilistic nature of the data. The original contributions of this work are twofold. First, several novel pattern recognition methods in non-Euclidean spaces of probability distribution functions (PDFs) are developed and validated. The second main contribution lies in the application of these and other techniques to a systematic analysis of ELMs in tokamak plasmas. In regard to the methodological aims of the work, we employ the framework of information geometry to develop pattern visualization and classification methods in spaces of probability distributions. In information geometry, a family of probability distributions is considered as a Riemannian manifold. Every point on the manifold represents a single PDF and the distribution parameters provide local coordinates on the manifold. The Fisher information plays the role of a Riemannian metric tensor, enabling calculation of geodesic curves on the surface. The length of such curves yields the geodesic distance (GD) on probabilistic manifolds, which is a natural similarity (distance) measure between PDFs. Equipped with a suitable distance measure, we extrapolate several distance-based pattern recognition methods to the manifold setting. This includes k-nearest neighbor (kNN) and conformal predictor (CP) methods for classification, as well as multidimensional

  20. Experimental analysis of considering the sound pressure distribution pattern at the ear canal entrance as an unrevealed head-related localization clue

    Institute of Scientific and Technical Information of China (English)

    TONG Xin; QI Na; MENG Zihou

    2018-01-01

    By analyzing the differences between binaural recording and real listening,it was deduced that there were some unrevealed auditory localization clues,and the sound pressure distribution pattern at the entrance of ear canal was probably a clue.It was proved through the listening test that the unrevealed auditory localization clues really exist with the reduction to absurdity.And the effective frequency bands of the unrevealed localization clues were induced and summed.The result of finite element based simulations showed that the pressure distribution at the entrance of ear canal was non-uniform,and the pattern was related to the direction of sound source.And it was proved that the sound pressure distribution pattern at the entrance of the ear canal carried the sound source direction information and could be used as an unrevealed localization cluc.The frequency bands in which the sound pressure distribution patterns had significant differences between front and back sound source directions were roughly matched with the effective frequency bands of unrevealed localization clues obtained from the listening tests.To some extent,it supports the hypothesis that the sound pressure distribution pattern could be a kind of unrevealed auditory localization clues.

  1. Distribution of involved regional lymph nodes in recurrent and locally advanced breast cancer and its impact on target definition

    International Nuclear Information System (INIS)

    Chen Jian; Ma Jinli; Zhang Shengjian; Yang Zhaozhi; Cai Gang; Feng Yan; Guo Xiaomao; Chen Jiayi

    2011-01-01

    Objective: The frequency and the anatomic distribution of involved regional nodes in recurrent and locally advanced breast cancer were analyzed, in order to evaluate the rational of conventional regional node radiation technique and provide evidence for target definition of breast cancer . Methods: Patients with recurrent or locally advanced breast cancer who were treated in our hospital from August 2003 to December 2009 were included in this study. 111 patients had contrast enhanced chest CT images of the whole regional nodes before treatment. The regional nodes were categorized into 8 anatomical substructures including medial and lateral supraclavicular nodes ( SC-M, SC-L), axilla nodes ( ALN )- I , II , III, infra clavicular nodes (IFN), Rotter's nodes (RN) and internal mammary nodes (IMN). The frequency of involvement and anatomical distribution of the involved nodes on CT images were analyzed. Results: A total of 111 patients were enrolled this study and 199 anatomical substructures with involved nodes were identified. The frequency of involvement were : SC-M 33, SC-L 21, ALN- I 30, ALN-II 25, ALN-III + IFN 35, RN 27, IMN 28. Supraclavicular region and axilla were the most frequently involved area (72.3%). The average depth of the SC-M and SC-L nodes was 33.48 mm ± 10. 57 mm and 45.62 mm ±20. 45 mm, and 51.5% and 71.4% of the SC-M and SC-L nodes were located more than 3 cm deep from the skin. The axilla nodes were located cranial and caudal to the axillary vein in 5 and 20 locally advanced breast cancer patients and in 64 and 28 patients who received prior axillary dissection. The majority of involved IMN was located within the first 3 intercostal spaces (26/28). The average distance between the center of involved IMN and chest skin was 24. 23 mm ± 10. 28 mm. The average distance between the center of involved IMN and midline of the body was 29. 38 mm ±6. 7 mm. The center of involved IMN was 6.19 mm ±5.73 mm lateral and 5.73 mm ± 4. 56 mm posterior to

  2. Distribution

    Science.gov (United States)

    John R. Jones

    1985-01-01

    Quaking aspen is the most widely distributed native North American tree species (Little 1971, Sargent 1890). It grows in a great diversity of regions, environments, and communities (Harshberger 1911). Only one deciduous tree species in the world, the closely related Eurasian aspen (Populus tremula), has a wider range (Weigle and Frothingham 1911)....

  3. Predicting the impacts of climate change on animal distributions: the importance of local adaptation and species' traits

    Energy Technology Data Exchange (ETDEWEB)

    HELLMANN, J. J.; LOBO, N. F.

    2011-12-20

    The geographic range limits of many species are strongly affected by climate and are expected to change under global warming. For species that are able to track changing climate over broad geographic areas, we expect to see shifts in species distributions toward the poles and away from the equator. A number of ecological and evolutionary factors, however, could restrict this shifting or redistribution under climate change. These factors include restricted habitat availability, restricted capacity for or barriers to movement, or reduced abundance of colonists due the perturbation effect of climate change. This research project examined the last of these constraints - that climate change could perturb local conditions to which populations are adapted, reducing the likelihood that a species will shift its distribution by diminishing the number of potential colonists. In the most extreme cases, species ranges could collapse over a broad geographic area with no poleward migration and an increased risk of species extinction. Changes in individual species ranges are the processes that drive larger phenomena such as changes in land cover, ecosystem type, and even changes in carbon cycling. For example, consider the poleward range shift and population outbreaks of the mountain pine beetle that has decimated millions of acres of Douglas fir trees in the western US and Canada. Standing dead trees cause forest fires and release vast quantities of carbon to the atmosphere. The beetle likely shifted its range because it is not locally adapted across its range, and it appears to be limited by winter low temperatures that have steadily increased in the last decades. To understand range and abundance changes like the pine beetle, we must reveal the extent of adaptive variation across species ranges - and the physiological basis of that adaptation - to know if other species will change as readily as the pine beetle. Ecologists tend to assume that range shifts are the dominant

  4. In situ localization and tissue distribution of ostreid herpesvirus 1 proteins in infected Pacific oyster, Crassostrea gigas.

    Science.gov (United States)

    Martenot, Claire; Segarra, Amélie; Baillon, Laury; Faury, Nicole; Houssin, Maryline; Renault, Tristan

    2016-05-01

    Immunohistochemistry (IHC) assays were conducted on paraffin sections from experimentally infected spat and unchallenged spat produced in hatchery to determine the tissue distribution of three viral proteins within the Pacific oyster, Crassostrea gigas. Polyclonal antibodies were produced from recombinant proteins corresponding to two putative membrane proteins and one putative apoptosis inhibitor encoded by ORF 25, 72, and 87, respectively. Results were then compared to those obtained by in situ hybridization performed on the same individuals, and showed a substantial agreement according to Landis and Koch numeric scale. Positive signals were mainly observed in connective tissue of gills, mantle, adductor muscle, heart, digestive gland, labial palps, and gonads of infected spat. Positive signals were also reported in digestive epithelia. However, few positive signals were also observed in healthy appearing oysters (unchallenged spat) and could be due to virus persistence after a primary infection. Cellular localization of staining seemed to be linked to the function of the viral protein targeted. A nucleus staining was preferentially observed with antibodies targeting the putative apoptosis inhibitor protein whereas a cytoplasmic localization was obtained using antibodies recognizing putative membrane proteins. The detection of viral proteins was often associated with histopathological changes previously reported during OsHV-1 infection by histology and transmission electron microscopy. Within the 6h after viral suspension injection, positive signals were almost at the maximal level with the three antibodies and all studied organs appeared infected at 28h post viral injection. Connective tissue appeared to be a privileged site for OsHV-1 replication even if positive signals were observed in the epithelium cells of different organs which may be interpreted as a hypothetical portal of entry or release for the virus. IHC constitutes a suited method for analyzing the

  5. An ultrastructural and irradiation study of diffuse and localised kinetochore

    International Nuclear Information System (INIS)

    Bokhari, F.S.

    1979-05-01

    An electron microscope study of plant types Luzula nivea and Cyperus eragrostis with diffuse kinetochores and Crepis neglecta with localised kinetochore showed that Luzula has a rather different kinetochore organisation from Cyperus, with features approaching the localised type of Crepis. These studies included an examination of the ultrastructure of the kinetochore at metaphase at low magnification in control and irradiated material of Luzula; the chromosomal ultrastructure at high magnification at interphase and all stages of mitosis in Luzula, Cyperus and Crepis; and the ultrastructure of the nucleolus in Luzula, Cyperus and Crepis. Light microscopic studies were also performed showing the effects of irradiation on first mitotic division in Cyperus, Luzula and Crepis, mitotic aberrations in Cyperus and Crepis and meiosis in Cyperus. Finally, the survival with the diffuse as opposed to the localised kinetochore in M 1 and M 2 generations following seed irradiation was studied. (U.K.)

  6. Ultrastructural hepatocellular features associated with severe hepatic lipidosis in cats.

    Science.gov (United States)

    Center, S A; Guida, L; Zanelli, M J; Dougherty, E; Cummings, J; King, J

    1993-05-01

    In this study, we compared hepatic ultrastructure in healthy cats, in cats with severe hepatic lipidosis, and in cats with experimentally induced, chronic, extrahepatic bile duct occlusion. Ultrastructural features unique to the lipidosis syndrome included an apparent reduction in number of peroxisomes and alteration in their morphologic features. The quantity of endoplasmic reticulum, Golgi complexes, and lysosomes was subjectively reduced, and paucity of cytosolic glycogen was observed. Bile canaliculi appeared collapsed because of cytosolic distention with lipid. Mitochondria were reduced in number and were markedly pleomorphic. Cristae assumed a variety of shapes, lengths, and orientations. Ultrastructural features of bile duct occlusion were similar to those described in other species and differed from those in cats with hepatic lipidosis.

  7. Chromium-Induced Ultrastructural Changes and Oxidative Stress in Roots of Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Eleftherios P. Eleftheriou

    2015-07-01

    Full Text Available Chromium (Cr is an abundant heavy metal in nature, toxic to living organisms. As it is widely used in industry and leather tanning, it may accumulate locally at high concentrations, raising concerns for human health hazards. Though Cr effects have extensively been investigated in animals and mammals, in plants they are poorly understood. The present study was then undertaken to determine the ultrastructural malformations induced by hexavalent chromium [Cr(VI], the most toxic form provided as 100 μM potassium dichromate (K2Cr2O7, in the root tip cells of the model plant Arabidopsis thaliana. A concentration-dependent decrease of root growth and a time-dependent increase of dead cells, callose deposition, hydrogen peroxide (H2O2 production and peroxidase activity were found in Cr(VI-treated seedlings, mostly at the transition root zone. In the same zone, nuclei remained ultrastructurally unaffected, but in the meristematic zone some nuclei displayed bulbous outgrowths or contained tubular structures. Endoplasmic reticulum (ER was less affected under Cr(VI stress, but Golgi bodies appeared severely disintegrated. Moreover, mitochondria and plastids became spherical and displayed translucent stroma with diminished internal membranes, but noteworthy is that their double-membrane envelopes remained structurally intact. Starch grains and electron dense deposits occurred in the plastids. Amorphous material was also deposited in the cell walls, the middle lamella and the vacuoles. Some vacuoles were collapsed, but the tonoplast appeared integral. The plasma membrane was structurally unaffected and the cytoplasm contained opaque lipid droplets and dense electron deposits. All electron dense deposits presumably consisted of Cr that is sequestered from sensitive sites, thus contributing to metal tolerance. It is concluded that the ultrastructural changes are reactive oxygen species (ROS-correlated and the malformations observed are organelle specific.

  8. THE HERSCHEL EXPLOITATION OF LOCAL GALAXY ANDROMEDA (HELGA). VI. THE DISTRIBUTION AND PROPERTIES OF MOLECULAR CLOUD ASSOCIATIONS IN M31

    Energy Technology Data Exchange (ETDEWEB)

    Kirk, J. M. [Jeremiah Horrocks Institute, University of Central Lancashire, Preston PR1 2HE (United Kingdom); Gear, W. K.; Smith, M. W. L.; Ford, G.; Eales, S. A.; Gomez, H. L. [School of Physics and Astronomy, Cardiff University, Queens Buildings, The Parade, Cardiff, Wales CF24 3AA (United Kingdom); Fritz, J.; Baes, M.; De Looze, I.; Gentile, G.; Gordon, K.; Verstappen, J.; Viaene, S. [Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281 S9, B-9000 Gent (Belgium); Bendo, G. J. [UK ALMA Regional Centre Node, Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom); O' Halloran, B. [Astrophysics Group, Imperial College, Blackett Laboratory, Prince Consort Road, London SW7 2AZ (United Kingdom); Madden, S. C.; Lebouteiller, V. [Laboratoire AIM, CEA/DSM-CNRS-Université Paris Diderot, Irfu/Service, Paris, F-91190 Gif-sur-Yvette (France); Roman-Duval, J. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Boselli, A. [Laboratoire d' Astrophysique de Marseille, UMR 7326 CNRS, 38 rue F. Joliot-Curie, F-13388 Marseille (France); Cooray, A. [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); and others

    2015-01-01

    In this paper we present a catalog of giant molecular clouds (GMCs) in the Andromeda (M31) galaxy extracted from the Herschel Exploitation of Local Galaxy Andromeda (HELGA) data set. GMCs are identified from the Herschel maps using a hierarchical source extraction algorithm. We present the results of this new catalog and characterize the spatial distribution and spectral energy properties of its clouds based on the radial dust/gas properties found by Smith et al. A total of 326 GMCs in the mass range 10{sup 4}-10{sup 7} M {sub ☉} are identified; their cumulative mass distribution is found to be proportional to M {sup –2.34}, in agreement with earlier studies. The GMCs appear to follow the same correlation of cloud mass to L {sub CO} observed in the Milky Way. However, comparison between this catalog and interferometry studies also shows that the GMCs are substructured below the Herschel resolution limit, suggesting that we are observing associations of GMCs. Following Gordon et al., we study the spatial structure of M31 by splitting the observed structure into a set of spiral arms and offset rings. We fit radii of 10.3 and 15.5 kpc to the two most prominent rings. We then fit a logarithmic spiral with a pitch angle of 8.°9 to the GMCs not associated with either ring. Last, we comment on the effects of deprojection on our results and investigate the effect different models for M31's inclination will have on the projection of an unperturbed spiral arm system.

  9. Local distribution of wall static pressure and heat transfer on a rough flat plate impinged by a slot air jet

    Science.gov (United States)

    Meda, Adimurthy; Katti, Vadiraj V.

    2017-08-01

    The present work experimentally investigates the local distribution of wall static pressure and the heat transfer coefficient on a rough flat plate impinged by a slot air jet. The experimental parameters include, nozzle-to-plate spacing (Z /D h = 0.5-10.0), axial distance from stagnation point ( x/D h ), size of detached rib ( b = 4-12 mm) and Reynolds number ( Re = 2500-20,000). The wall static pressure on the surface is recorded using a Pitot tube and a differential pressure transmitter. Infrared thermal imaging technique is used to capture the temperature distribution on the target surface. It is observed that, the maximum wall static pressure occurs at the stagnation point ( x/D h = 0) for all nozzle-to-plate spacing ( Z/D h ) and rib dimensions studied. Coefficient of wall static pressure ( C p ) decreases monotonically with x/D h . Sub atmospheric pressure is evident in the detached rib configurations for jet to plate spacing up to 6.0 for all ribs studied. Sub atmospheric region is stronger at Z/D h = 0.5 due to the fluid accelerating under the rib. As nozzle to plate spacing ( Z/D h ) increases, the sub-atmospheric region becomes weak and vanishes gradually. Reasonable enhancement in both C p as well as Nu is observed for the detached rib configuration. Enhancement is found to decrease with the increase in the rib width. The results of the study can be used in optimizing the cooling system design.

  10. New large-deviation local theorems for sums of independent and identically distributed random vectors when the limit distribution is α-stable

    OpenAIRE

    Nagaev, Alexander; Zaigraev, Alexander

    2005-01-01

    A class of absolutely continuous distributions in Rd is considered. Each distribution belongs to the domain of normal attraction of an α-stable law. The limit law is characterized by a spectral measure which is absolutely continuous with respect to the spherical Lebesgue measure. The large-deviation problem for sums of independent and identically distributed random vectors when the underlying distribution belongs to that class is studied. At the focus of attention are the deviations in the di...

  11. Spermatogenesis and sperm ultrastructure in the polychaete genus Ophryotrocha (Dorvilleidae)

    Science.gov (United States)

    Pfannenstiel, Hans-Dieter; Grünig, Charlotte

    1990-06-01

    The details of spermatogenesis and spermiogenesis are described for Ophryotrocha puerilis. The ultrastructure of mature sperm is shown for O. puerilis, O. hartmanni, O. gracilis, O. diadema, O. labronica, and O. notoglandulata. Clusters of sixteen cells each are proliferated by two stem cells in each setigerous segment of O. puerilis representing the very early stages of both oogenesis and spermatogenesis. In each spermatocyte-I cluster, the cells are interconnected by cytoplasmic bridges. Early, clusters are enveloped by peritoneal sheath cells. These transient gonad walls break down prior to meiosis. The meiotic processes may start in the clusters with the cells still interconnected, or during breakdown of the original cluster, giving rise to smaller subclusters of both spermatocytes I and spermatocytes II with various numbers of cells. Finally, spermatid tetrads are present. As spermiogenesis progresses, the tetrads disintegrate. Golgi vesicles in both spermatocytes and spermatids contain electron-dense material, presumably preacrosomal. The acrosome is formed by such vesicles. In the six species studied here, the acrosomes appear to be of a similar overall structure but are of different shape. Centrioles are usually located beneath the acrosome. The distal centriole forms the basal body of a flagellum-like cytoplasmic process. The microtubules of these flagellar equivalents do not show a normal ciliar arrangement. The flagellar equivalent appears to be non-motile. In O. hartmanni and in O. notoglandulata, a flagellar equivalent is missing. Microtubules originating from the proximal end of the distal centriole stretch to the nuclear envelope. This feature appears to be especially conspicuous in O. puerilis and in O. labronica. In O. labronica and in O. notoglandulata, bundles of microtubules paralleling the cell perimeter appear to stabilise the sperm. Various numbers of mitochondria are either randomly distributed around the nucleus or accumulate on one side

  12. The role of immunohistochemistry, electron microscopy, and ultrastructural cytochemistry in the diagnosis of mixed carcinoma-neuroendocrine neoplasms.

    Science.gov (United States)

    Graham, A R; Payne, C M; Nagle, R B; Angel, E

    1987-02-01

    We studied four mixed carcinoma-neuroendocrine neoplasms from gastrointestinal tract and pancreas by routine light microscopy (LM), immunohistochemistry (IH), electron microscopy (EM), and ultrastructural cytochemistry (UC). By LM, the individual tumors showed fairly pure neuroendocrine (carcinoid) or epithelial (papillary) patterns, mixed neuroendocrine-carcinoma features and poorly-differentiated tumor in sheets and nests which did not lend itself to morphologic characterization. IH demonstrated mixed expression, within different areas of the same neoplasm, of epithelial antigens (keratins and carcinoembryonic antigen [CEA]) and neuroendocrine markers (neuron-specific enolase [NSE], bombesin and neurohormonal peptides). By EM, each tumor showed ultrastructural features of epithelial and neuroendocrine differentiation which varied substantially in terms of number of cells involved and their distribution; two of the neoplasms showed biphasic differentiation within single cells. The nature of the neurosecretory granules was verified with the uranaffin reaction (UR). This study illustrates the value of combining LM, IH, EM and UC for the identification of mixed carcinoma-neuroendocrine lesions.

  13. Distributed and localized horizontal tectonic deformation as inferred from drainage network geometry and topology: A case study from Lebanon

    Science.gov (United States)

    Goren, Liran; Castelltort, Sébastien; Klinger, Yann

    2016-04-01

    Partitioning of horizontal deformation between localized and distributed modes in regions of oblique tectonic convergence is, in many cases, hard to quantify. As a case study, we consider the Dead Sea Fault System that changes its orientation across Lebanon and forms a restraining bend. The oblique deformation along the Lebanese restraining bend is characterized by a complex suite of tectonic structures, among which, the Yammouneh fault, is believed to be the main strand that relays deformation from the southern section to the northern section of the Dead Sea Fault System. However, uncertainties regarding slip rates along the Yammouneh fault and strain partitioning in Lebanon still prevail. In the current work we use the geometry and topology of river basins together with numerical modeling to evaluate modes and rates of the horizontal deformation in Mount Lebanon that is associated with the Arabia-Sinai relative plate motion. We focus on river basins that drain Mount Lebanon to the Mediterranean and originate close to the Yammouneh fault. We quantify a systematic counterclockwise rotation of these basins and evaluate drainage area disequilibrium using an application of the χ mapping technique, which aims at estimating the degree of geometrical and topological disequilibrium in river networks. The analysis indicates a systematic spatial pattern whereby tributaries of the rotated basins appear to experience drainage area loss or gain with respect to channel length. A kinematic model that is informed by river basin geometry reveals that since the late Miocene, about a quarter of the relative plate motion parallel to the plate boundary has been distributed along a wide band of deformation to the west of the Yammouneh fault. Taken together with previous, shorter-term estimates, the model indicates little variation of slip rate along the Yammouneh fault since the late Miocene. Kinematic model results are compatible with late Miocene paleomagnetic rotations in western

  14. Early studies of placental ultrastructure by electron microscopy

    DEFF Research Database (Denmark)

    Carter, A M; Enders, A C

    2016-01-01

    many other scientists to Washington University in St. Louis. Work on human placental ultrastructure was initiated at Cambridge and Kyoto whilst domestic animals were initially studied by Björkman in Stockholm and electron micrographs of bat placenta were published by Wimsatt of Cornell University......BACKGROUND: Transmission electron microscopy (TEM) was first applied to study placental ultrastructure in the 1950's. We review those early studies and mention the scientists that employed or encouraged the use of TEM. FINDINGS: Among the pioneers Edward W. Dempsey was a key figure who attracted...

  15. Ultrastructural studies of Biomphalaria glabrata (Say, 1818) embryo

    International Nuclear Information System (INIS)

    Kikuchi, O.K.; Okazaki, K.; Kawano, T.; Ribeiro, A.A.G.F.C.

    1988-09-01

    Ultrastructural studies of Biomphalaria glabrata embryos (MOllusca: Gastropoda), and important snail vector of schistosomiasis has not been explored. In the present work it was evaluated a suitable electron microscopical technique for embryos processing. Promising results was obtained with double fixation in 1% glutaraldehyde plus 1% osmium tetroxide in 0.05 M cacodylate buffer (pH 7.4), preliminary staining overnight in 1% uranyl acetate and embedding in EPON or Polylite under vacuum. It was used embryos at young trochophore stage wich is characterized by active organogenesis. Some ultrastructural aspects of B. glabrata embryos cells are presented. (author) [pt

  16. Distribution of local critical current along sample length and its relation to overall current in a long Bi2223/Ag superconducting composite tape

    International Nuclear Information System (INIS)

    Ochiai, S; Doko, D; Okuda, H; Oh, S S; Ha, D W

    2006-01-01

    The distribution of the local critical current and the n-value along the sample length and its relation to the overall critical current were studied experimentally and analytically for the bent multifilamentary Bi2223/Ag/Ag-Mg alloy superconducting composite tape. Then, based on the results, it was attempted to simulate on a computer the dependence of the critical current on the sample length. The main results are summarized as follows. The experimentally observed relation of the distributed local critical current and n-value to the overall critical current was described comprehensively with a simple voltage summation model, in which the sample was regarded as a one-dimensional series circuit. The sample length dependence of the critical current was reproduced on the computer by a Monte Carlo simulation incorporating the voltage summation model and the regression analysis results for the local critical current distribution and the relation of the n-value to the critical current

  17. Simplification of neural network model for predicting local power distributions of BWR fuel bundle using learning algorithm with forgetting

    International Nuclear Information System (INIS)

    Tanabe, Akira; Yamamoto, Toru; Shinfuku, Kimihiro; Nakamae, Takuji; Nishide, Fusayo.

    1995-01-01

    Previously a two-layered neural network model was developed to predict the relation between fissile enrichment of each fuel rod and local power distribution in a BWR fuel bundle. This model was obtained intuitively based on 33 patterns of training signals after an intensive survey of the models. Recently, a learning algorithm with forgetting was reported to simplify neural network models. It is an interesting subject what kind of model will be obtained if this algorithm is applied to the complex three-layered model which learns the same training signals. A three-layered model which is expanded to have direct connections between the 1st and the 3rd layer elements has been constructed and the learning method of normal back propagation was applied first to this model. The forgetting algorithm was then added to this learning process. The connections concerned with the 2nd layer elements disappeared and the 2nd layer has become unnecessary. It took a longer computing time by an order to learn the same training signals than the simple back propagation, but the two-layered model was obtained autonomously from the expanded three-layered model. (author)

  18. Tissue distribution, subcellular localization and endocrine disruption patterns induced by Cr and Mn in the crab Ucides cordatus

    International Nuclear Information System (INIS)

    Correa, Jose Dias; Ramos da Silva, Miguel; Bastos da Silva, Antonio Carlos; Araujo de Lima, Silene Maria; Malm, Olaf; Allodi, Silvana

    2005-01-01

    The essential trace elements Cr and Mn are toxic at high concentrations and information about low concentration is insufficient in the literature. In polluted mangroves, the crab Ucides cordatus can represent a useful tool to assess information on the potential impact of trace elements like Cr and Mn on the environment, since this species is comestible and thus, commercially negotiated. Therefore, U. cordatus crabs were exposed in vivo to different concentrations of Cr and Mn solved in seawater and had their tissue distribution and subcellular deposits evaluated. The gill, hepatopancreas and muscle concentrations were determined by atomic absorption spectroscopy and the results showed that Cr and Mn presented the highest values in the gills rather than in the hepatopancreas and muscular tissue. Electron microscopy and analytical X-ray microanalysis revealed Cr precipitates on the gill surface, co-localized with epiphyte bacteria. In addition, since Cr and Mn did not equally accumulate in most of the tissues studied, glycemic rate of animals, which received injections of extracts of eyestalks of the contaminated crabs, were measured in order to evaluate whether the studied concentrations of Cr and Mn could produce any metabolic alteration. The results indicated that extracts of the eyestalks of crabs submitted to Cr and Mn salts and injected into normal crabs markedly influenced crustacean hyperglycemic hormone synthesis and/or release. The results are discussed with respect to sensitivity of the employed methods and the possible significance of the concentrations of Cr and Mn in the organisms

  19. Targeted disruption of the mouse Csrp2 gene encoding the cysteine- and glycine-rich LIM domain protein CRP2 result in subtle alteration of cardiac ultrastructure

    Directory of Open Access Journals (Sweden)

    Stoll Doris

    2008-08-01

    Full Text Available Abstract Background The cysteine and glycine rich protein 2 (CRP2 encoded by the Csrp2 gene is a LIM domain protein expressed in the vascular system, particularly in smooth muscle cells. It exhibits a bimodal subcellular distribution, accumulating at actin-based filaments in the cytosol and in the nucleus. In order to analyze the function of CRP2 in vivo, we disrupted the Csrp2 gene in mice and analysed the resulting phenotype. Results A ~17.3 kbp fragment of the murine Csrp2 gene containing exon 3 through 6 was isolated. Using this construct we confirmed the recently determined chromosomal localization (Chromosome 10, best fit location between markers D10Mit203 proximal and D10Mit150 central. A gene disruption cassette was cloned into exon 4 and a mouse strain lacking functional Csrp2 was generated. Mice lacking CRP2 are viable and fertile and have no obvious deficits in reproduction and survival. However, detailed histological and electron microscopic studies reveal that CRP2-deficient mice have subtle alterations in their cardiac ultrastructure. In these mice, the cardiomyocytes display a slight increase in their thickness, indicating moderate hypertrophy at the cellular level. Although the expression of several intercalated disc-associated proteins such as β-catenin, N-RAP and connexin-43 were not affected in these mice, the distribution of respective proteins was changed within heart tissue. Conclusion We conclude that the lack of CRP2 is associated with alterations in cardiomyocyte thickness and hypertrophy.

  20. Enhancement in statistical and image analysis for in situ µSXRF studies of elemental distribution and co-localization, using Dioscorea balcanica

    International Nuclear Information System (INIS)

    Dučić, Tanja; Borchert, Manuela; Savić, Aleksandar; Kalauzi, Aleksandar; Mitrović, Aleksandra; Radotić, Ksenija

    2013-01-01

    Synchrotron-radiation-based X-ray microfluorescence has been used for in situ investigation of the distribution of micronutrient and macronutrient elements in an unstained cross section of a stem of monocotyledonous liana plant Dioscorea balcanica Košanin. The elemental allocation has been quantified and the grouping/co-localization in straight and twisted stem internodes has been analysed. Synchrotron-based X-ray microfluorescence (µSXRF) is an analytical method suitable for in situ investigation of the distribution of micronutrient and macronutrient elements in several-micrometres-thick unstained biological samples, e.g. single cells and tissues. Elements are mapped and quantified at sub-p.p.m. concentrations. In this study the quantity, distribution and grouping/co-localization of various elements have been identified in straight and twisted internodes of the stems of the monocotyledonous climber D. balcanica Košanin. Three different statistical methods were employed to analyse the macro-nutrient and micronutrient distributions and co-localization. Macronutrient elements (K, P, Ca, Cl) are distributed homogeneously in both straight and twisted internodes. Micronutrient elements are mostly grouped in the vasculature and in the sclerenchyma cell layer. In addition, co-localization of micronutrient elements is much more prominent in twisted than in straight internodes. These image analyses and statistical methods provided very similar outcomes and could be applied to various types of biological samples imaged by µSXRF

  1. Histopathology of Middle East respiratory syndrome coronovirus (MERS-CoV) infection - clinicopathological and ultrastructural study.

    Science.gov (United States)

    Alsaad, Khaled O; Hajeer, Ali H; Al Balwi, Mohammed; Al Moaiqel, Mohammed; Al Oudah, Nourah; Al Ajlan, Abdulaziz; AlJohani, Sameera; Alsolamy, Sami; Gmati, Giamal E; Balkhy, Hanan; Al-Jahdali, Hamdan H; Baharoon, Salim A; Arabi, Yaseen M

    2018-02-01

    The pathogenesis, viral localization and histopathological features of Middle East respiratory syndrome - coronavirus (MERS-CoV) in humans are not described sufficiently. The aims of this study were to explore and define the spectrum of histological and ultrastructural pathological changes affecting various organs in a patient with MERS-CoV infection and represent a base of MERS-CoV histopathology. We analysed the post-mortem histopathological findings and investigated localisation of viral particles in the pulmonary and extrapulmonary tissue by transmission electron microscopic examination in a 33-year-old male patient of T cell lymphoma, who acquired MERS-CoV infection. Tissue needle biopsies were obtained from brain, heart, lung, liver, kidney and skeletal muscle. All samples were collected within 45 min from death to reduce tissue decomposition and artefact. Histopathological examination showed necrotising pneumonia, pulmonary diffuse alveolar damage, acute kidney injury, portal and lobular hepatitis and myositis with muscle atrophic changes. The brain and heart were histologically unremarkable. Ultrastructurally, viral particles were localised in the pneumocytes, pulmonary macrophages, renal proximal tubular epithelial cells and macrophages infiltrating the skeletal muscles. The results highlight the pulmonary and extrapulmonary pathological changes of MERS-CoV infection and provide the first evidence of the viral presence in human renal tissue, which suggests tissue trophism for MERS-CoV in kidney. © 2017 John Wiley & Sons Ltd.

  2. Pb and Cd on growth, leaf ultrastructure and essential oil yield mint (Mentha arvensis L.

    Directory of Open Access Journals (Sweden)

    Caroline Nery Jezler

    2015-03-01

    Full Text Available Contamination of medicinal plants with heavy metals as Pb and Cd can affect the growth and the essential oil production of the plants and represent a risk to those who consume as medicine. This study aimed to evaluate the effects of absorption and localization of Pb and Cd on growth, ultrastructural aspects of leaves and essential oil yield and composition of Mentha arvensis, applied on the soil with increasing concentrations (8, 16, 32, 64 and 128mg kg-1. There was a differential absorption of Pb and Cd by M. arvensis mainly concentrated in the roots. Pb was found in small amounts in the leaves while Cd largely exceeded the safety limit without symptoms of toxicity. The ultrastructural analysis revealed the metal accumulation on vesicles surrounding the mitochondria and the presence of electron dense deposits surrounding the mitochondria, nucleus and chloroplasts. Little changes caused by Pb and Cd application were not enough to affect the growth and essential oil yield and composition of M. arvensis

  3. GEITLERINEMA SPECIES (OSCILLATORIALES, CYANOBACTERIA) REVEALED BY CELLULAR MORPHOLOGY, ULTRASTRUCTURE, AND DNA SEQUENCING(1).

    Science.gov (United States)

    Do Carmo Bittencourt-Oliveira, Maria; Do Nascimento Moura, Ariadne; De Oliveira, Mariana Cabral; Sidnei Massola, Nelson

    2009-06-01

    Geitlerinema amphibium (C. Agardh ex Gomont) Anagn. and G. unigranulatum (Rama N. Singh) Komárek et M. T. P. Azevedo are morphologically close species with characteristics frequently overlapping. Ten strains of Geitlerinema (six of G. amphibium and four of G. unigranulatum) were analyzed by DNA sequencing and transmission electronic and optical microscopy. Among the investigated strains, the two species were not separated with respect to cellular dimensions, and cellular width was the most varying characteristic. The number and localization of granules, as well as other ultrastructural characteristics, did not provide a means to discriminate between the two species. The two species were not separated either by geography or environment. These results were further corroborated by the analysis of the cpcB-cpcA intergenic spacer (PC-IGS) sequences. Given the fact that morphology is very uniform, plus the coexistence of these populations in the same habitat, it would be nearly impossible to distinguish between them in nature. On the other hand, two of the analyzed strains were distinct from all others based on the PC-IGS sequences, in spite of their morphological similarity. PC-IGS sequences indicate that these two strains could be a different species of Geitlerinema. Using morphology, cell ultrastructure, and PC-IGS sequences, it is not possible to distinguish G. amphibium and G. unigranulatum. Therefore, they should be treated as one species, G. unigranulatum as a synonym of G. amphibium. © 2009 Phycological Society of America.

  4. Histological and Ultrastructural Effects of Ultrasound-induced Cavitation on Human Skin Adipose Tissue.

    Science.gov (United States)

    Bani, Daniele; Quattrini Li, Alessandro; Freschi, Giancarlo; Russo, Giulia Lo

    2013-09-01

    In aesthetic medicine, the most promising techniques for noninvasive body sculpturing purposes are based on ultrasound-induced fat cavitation. Liporeductive ultrasound devices afford clinically relevant subcutaneous fat pad reduction without significant adverse reactions. This study aims at evaluating the histological and ultrastructural changes induced by ultrasound cavitation on the different cell components of human skin. Control and ultrasound-treated ex vivo abdominal full-thickness skin samples and skin biopsies from patients pretreated with or without ultrasound cavitation were studied histologically, morphometrically, and ultrastructurally to evaluate possible changes in adipocyte size and morphology. Adipocyte apoptosis and triglyceride release were also assayed. Clinical evaluation of the effects of 4 weekly ultrasound vs sham treatments was performed by plicometry. Compared with the sham-treated control samples, ultrasound cavitation induced a statistically significant reduction in the size of the adipocytes (P ultrasound treatment caused a significant reduction of abdominal fat. This study further strengthens the current notion that noninvasive transcutaneous ultrasound cavitation is a promising and safe technology for localized reduction of fat and provides experimental evidence for its specific mechanism of action on the adipocytes.

  5. Echinococcus multilocularis Leuckart, 1863 (Taeniidae): new data on sperm ultrastructure.

    Science.gov (United States)

    Miquel, Jordi; Świderski, Zdzisław; Azzouz-Maache, Samira; Pétavy, Anne-Françoise

    2016-06-01

    The present study establishes the ultrastructural organisation of the mature spermatozoon of Echinococcus multilocularis, which is essential for future research on the location of specific proteins involved in the sperm development in this species and also in Echinococcus granulosus. Thus, the ultrastructural characteristics of the sperm cell are described by means of transmission electron microscopy. The spermatozoon of E. multilocularis is a filiform cell, which is tapered at both extremities and lacks mitochondria. It exhibits all the characteristics of type VII spermatozoon of tapeworms, namely a single axoneme, crested bodies, spiralled cortical microtubules and nucleus, a periaxonemal sheath and intracytoplasmic walls. Other characteristics observed in the male gamete are the presence of a >900-nm long apical cone in its anterior extremity and only the axoneme in its posterior extremity. The ultrastructural characters of the spermatozoon of E. multilocularis are compared with those of other cestodes studied to date, with particular emphasis on representatives of the genus Taenia. The most interesting finding concerns the presence of two helical crested bodies in E. multilocularis while in the studied species of Taenia, there is only one crested body. Future ultrastructural studies of other species of the genus Echinococcus would be of particular interest in order to confirm whether or not the presence of two crested bodies is a characteristic of this genus.

  6. Biological, Histological and Ultra-Structural Studies of Female Mullet ...

    African Journals Online (AJOL)

    Biological, Histological and Ultra-Structural Studies of Female Mullet, Mugil cephalus , Ovaries Collected from Different Habitats during Annual Reproductive Cycle. ... 35 and 52 cm, respectively; whereas, the total number of ripe ova in brackish water fish ranged from 0.57±0.14 to 3.81±0.59 x106 for the same length groups.

  7. Ultrastructure of interstitial cells in subserosa of human colon

    DEFF Research Database (Denmark)

    Rumessen, Jüri Johannes; Vanderwinden, Jean-Marie; Hansen, Alastair

    2013-01-01

    vesicles) were prominent. The IC-SS ultrastructure was different from that of FLC in the longitudinal layer, which had no caveolae and fewer intermediate filaments. Peg-and-socket junctions between IC-SS and between IC-SS and muscle cells were present, and IC-SS processes had close, selective appositions...

  8. Ultrastructure of Proechinophthirus zumpti (Anoplura, Echinophthiriidae by scanning electron microscopy

    Directory of Open Access Journals (Sweden)

    Dolores del Carmen Castro

    2002-09-01

    Full Text Available The ultrastructure of Proechinophthirus zumpti Werneck, 1955, mainly the external chorionic features of the egg, is described through electronic microscopy techniques. This species was first cited in Argentina, infesting Arctocephalus australis (Zimmermann, 1873. The morphological adaptations of adults and nymphs are described in both species of Proechinophthirus parasitic on Otariidae: P. fluctus (Ferris, 1916 and P. zumpti.

  9. Surface ultrastructure of third-instar Megaselia scalaris (Diptera: Phoridae

    Directory of Open Access Journals (Sweden)

    Sukontason Kabkaew L

    2002-01-01

    Full Text Available We describe some ultrastructure of the third-instar Megaselia scalaris (Diptera: Phoridae using scanning electron microscopy, with the cephalic segment, anterior spiracle and posterior spiracle being emphasized. This study provides the taxonomic information of this larval species, which may be useful to differentiate from other closely-related species.

  10. The ultrastructure of the midgut epithelium in millipedes (Myriapoda, Diplopoda)

    Czech Academy of Sciences Publication Activity Database

    Sosinka, A.; Rost-Roszkowska, M.M.; Vilímová, J.; Tajovský, Karel; Kszuk-Jendrysik, M.; Chajec, Ł.; Sonakowska, L.; Kamińska, K.; Hyra, M.; Poprawa, I.

    2014-01-01

    Roč. 43, č. 5 (2014), s. 477-492 ISSN 1467-8039 Institutional support: RVO:60077344 Keywords : digestive cells * midgut epithelium * millipedes * regenerative cells * secretory cells * ultrastructure Subject RIV: EG - Zoology Impact factor: 1.650, year: 2014

  11. Age-related ultrastructural and monoamine oxidase changes in the rat optic nerve.

    Science.gov (United States)

    Taurone, S; Ripandelli, G; Minni, A; Lattanzi, R; Miglietta, S; Pepe, N; Fumagalli, L; Micera, A; Pastore, F S; Artico, M

    2016-01-01

    The aim of this paper is to study the morphology and the distribution of the monoamine oxidase enzymatic system in the optic nerve of 4 month-old Wistar (young) and 28 month-old Wistar (old) rats. The optic nerve was harvested from 20 young and old rats. The segment of optic nerve was divided longitudinally into two pieces, each 0.1 mm in length. The first piece was used for transmission electron microscopy. The second piece was stained with histochemical reaction for monoamine oxidase. The agerelated changes in the optic nerve of rats include micro-anatomical details, ultrastructure and monoamine oxidase histochemical staining. A strong decrease of the thin nerve fibers and a swelling of the thick ones can be observed in optic nerve fibers of old rats. Increased monoamine oxidase histochemical staining of the optic nerve of aged rats is well demonstrated. The increase of meningeal shealth and the decrease of thin nerve fibers of the optic nerve in old rats are well documented. Morphological, ultrastructural and histochemical changes observed in optic nerve fibers of the old rats show a close relation with aging.

  12. [An ultrastructural study of oogenesis in the planarian Schmidtea mediterranea (Platyhelminthe, Paludicola)].

    Science.gov (United States)

    Harrath, Abdul Halim; Alwasal, Saleh H; Alhazza, Ibrahim; Zghal, Fathia; Tekaya, Saida

    2011-07-01

    The ovary of the freshwater planarian Schmidtea mediterranea has been studied for the first time using both light and electron microscopy methods. The ultrastructure of the ovary revealed two types of cells: accessory cells and germinal cells at various stages of differentiation, distributed along a maturation axis. Initially, oogonia underwent cytoplasm growth due to the development of organelles, such as endoplasmic reticulum, Golgi complex, and mitochondria, which are all involved in the production of cytoplasmic inclusions or yolk globules. It is shown that the chromatoid body and fibrogranular aggregates may participate in the synthesis of vitelline inclusions. When completely mature, the oocytes have become larger, due to the accumulation of nutritive inclusions, which are round in shape and have a paracrystalline structure. These inclusions are interpreted as being yolk globules and may represent a kind of nutritive material for the developing embryo. These ultrastructural features of the ovary agree with the available phylogenetic tree, based on morphological and karyological characters that considers Schmidtea group as a genus and not a subgenus. The presence of sperm between the oocytes suggests that fertilization may occur within the ovary, representing an uncommon condition within the Triclads, in which fertilization usually takes places outside of the ovaries. Copyright © 2011 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  13. Building blocks of the GIPU, Italian Group of Ultrastructural Pathology.

    Science.gov (United States)

    Papa, V; Costa, R; Cenacchi, G

    2016-06-01

    The Italian Group of Ultrastructural Pathology, GIPU, is a scientific organization committed to promote the art and science of Electron Microscopy (EM) in the pathology field in Italy, sharing its professional work with a public audience. The history of the GIPU goes back to 1990s when a founder group set up the Italian Group of Ultrastructural Diagnostic (GIDU) in Milan. The central focus of annual meetings was on EM, transmission and scanning one, about interesting cases in which it was instrumental in diagnosis. In the 1990s, ultrastructure was still the gold standard for cell/tissue morphology, biology, biochemistry, diagnostic pathology, and played an important role in tailored medicine. So, especially transmission EM, could play a critical role in the diagnosis of various diseases as in human as in animals. Best topics of the annual scientific meetings of the group were kidney, muscle, heart, and liver pathology, infertility, neuropathology, respiratory diseases, skin diseases, storage diseases, tumor pathology, infectious diseases, parasitology, veterinary pathology and more. Nowadays, EM is a method whose importance for diagnosis and pathology is well established: it is still essential in several pathologies, helpful in others, and welcome implemented in eclectic research pathology. Omission of EM likely makes the studies suboptimal and wasteful. So, from 2007 the name of the group has been changed to the Italian Group of Ultrastructural Pathology (GIPU) to favor broader applications of EM also to pathology research field. During last decades, GIDU/GIPU has interconnected with international (Society for Ultrastructural Pathology) and european (European Society of Pathology and Joint Meeting with the European Electron Microscopy Working Group) scientific society, according its statute. By 1991, GIPU has had 40 members: membership in this Group is still open and welcome to all pathologists, PhD, electron microscopy technologists, pathology trainees, and

  14. Distributional justice in Swedish wind power development – An odds ratio analysis of windmill localization and local residents’ socio-economic characteristics

    International Nuclear Information System (INIS)

    Liljenfeldt, Johanna; Pettersson, Örjan

    2017-01-01

    With a fast rise in large-scale wind power development in Sweden and other countries in recent years, issues related to energy justice generally and distributional justice specifically have become concerns in windmill siting. Some research, for instance, has indicated that it is easier to build windmills in economically marginalized communities. The evidence for this, however, is still limited. Thus, this study aims to statistically evaluate the extent to which the decisions to approve or reject windmill proposals in Sweden can be explained by factors related to the socio-economic characteristics of people living in the areas surrounding windmill sites. The study is based on an odds ratio analysis of decisions on all windmill proposals in Sweden, in which geo-referenced socio-economic data on an individual level for all inhabitants within 3 and 10 km of the windmill sites are studied. The results show skewness in the distribution of windmills, with a higher likelihood of rejection in areas with more highly educated people and people working in the private sector, compared to a higher likelihood of approval in areas with more unemployed people. This skewness, while not necessarily unjust, warrants further policy and research attention to distributional justice issues when developing wind power. - Highlights: • The distributional justice of windmill siting in Sweden is statistically evaluated. • Windmill siting decisions are related to people's socio-economic characteristics. • The results indicate some distributional skewness for wind power development. • The study gives statistical rigour and generalisability to energy justice findings. • The results warrant follow-ups and policy guides for how to handle benefit-sharing.

  15. Histopathological confirmation of similar intramucosal distribution of fluorescein in both intravenous administration and local mucosal application for probe-based confocal laser endomicroscopy of the normal stomach.

    Science.gov (United States)

    Nonaka, Kouichi; Ohata, Ken; Ban, Shinichi; Ichihara, Shin; Takasugi, Rumi; Minato, Yohei; Tashima, Tomoaki; Matsuyama, Yasushi; Takita, Maiko; Matsuhashi, Nobuyuki; Neumann, Helmut

    2015-12-16

    Probe-based confocal laser endomicroscopy (pCLE) is capable of acquiring in vivo magnified cross-section images of the gastric mucosa. Intravenous injection of fluorescein sodium is used for confocal imaging. However, it is still under debate if local administration of the dye to the mucosa is also effective for confocal imaging as it is not yet clear if topical application also reveals the intramucosal distribution of fluorescein. The objective of this study was to evaluate the intramucosal distribution of fluorescein sodium after topical application and to compare the distribution to the conventional intravenous injection used for confocal imaging. pCLE of the stomach uninfected with Helicobacter pylori was performed in a healthy male employing intravenous administration and local mucosal application of fluorescein. The mucosa of the lower gastric body was biopsied 1 min and 5 min after intravenous administration or local mucosal application of fluorescein, and the distribution of fluorescein in the biopsy samples was examined histologically. Green fluorescence was already observed in the cytoplasm of fundic glandular cells in the biopsied deep mucosa 1 min after local mucosal application of fluorescein. It was also observed in the foveolar lumen and inter-foveolar lamina propria, although it was noted at only a few sites. In the tissue biopsied 5 min after the local mucosal application of fluorescein, green fluorescence was more frequently noted in the cytoplasm of fundic glandular cells than in that 1 min after the local mucosal application of fluorescein, although obvious green fluorescence was not identified in the foveolar lumen or inter-foveolar lamina propria. The distribution of intravenously administered fluorescein in the cytoplasm of fundic glandular cells was also clearly observed similarly to that after local mucosal application of fluorescein. Green fluorescence in more cells was observed in many cells 5 min after intravenous administration compared

  16. Distribution Analysis of the Local Critical Temperature and Current Density in YBCO Coated Conductors using Low-temperature Scanning Laser and Hall Probe Microscopy

    International Nuclear Information System (INIS)

    Park, S. K.; Cho, B. R.; Park, H. Y.; Ri, H. C.

    2011-01-01

    Distribution of the local critical temperature and current density in YBCO coated conductors were analyzed using Low-temperature Scanning Laser and Hall Probe Microscopy (LTSLHPM). We prepared YBCO coated conductors of various bridge types to study the spatial distribution of the critical temperature and the current density in single and multi bridges. LTSLHPM system was modified for detailed linescan or two-dimensional scan both scanning laser and scanning Hall probe method simultaneously. We analyzed the local critical temperature of single and multi bridges from series of several linescans of scanning laser microscopy. We also investigated local current density and hysteresis curve of single bridge from experimental results of scanning Hall probe microscopy.

  17. Research article Ultrastructural studies and molecular ...

    Indian Academy of Sciences (India)

    mayank dwivedi

    In addition, this symbiosis influences the distribution and rarity of ... Orchid mycorrhizae are restricted to the angiosperm family, Orchidaceae, which is one .... genetic, hormonal, and environmental variables in the development of root hairs in ...

  18. Evaluation of stability and size distribution of sunflower oil-coated micro bubbles for localized drug delivery.

    Science.gov (United States)

    Filho, Walter Duarte de Araujo; Schneider, Fábio Kurt; Morales, Rigoberto E M

    2012-09-20

    Micro bubbles were initially introduced as contrast agents for ultrasound examinations as they are able to modify the signal-to-noise ratio in imaging, thus improving the assessment of clinical information on human tissue. Recent developments have demonstrated the feasibility of using these bubbles as drug carriers in localized delivery. In micro fluidics devices for generation of micro bubbles, the bubbles are formed at interface of liquid gas through a strangulation process. A device that uses these features can produce micro bubbles with small size dispersion in a single step. A T-junction micro fluidic device constructed using 3D prototyping was made for the production of mono dispersed micro bubbles. These micro bubbles use sunflower oil as a lipid layer. Stability studies for micro bubbles with diameters different generated from a liquid phase of the same viscosity were conducted to evaluate whether micro bubbles can be used as drug carriers. The biocompatibility of coating layer, the ability to withstand environmental pressure variations combined with echogenicity, are key factors that they can safely play the role of drug transporters. The normal distribution curve with small dispersion of the diameter of bubbles validates the process of generating micro bubbles with low value of variation coefficient, i.e., 0.381 at 1.90%. The results also showed the feasibility of using sunflower oil as the lipid matrix with stable population of bubbles over 217 minutes for micro bubbles with an average diameter of 313.04 μm and 121 minutes for micro bubbles with an average diameter of 73.74 μm, considering bubbles with air as gaseous phase. The results indicate that the micro fluidic device designed can be used for producing micro bubbles with low variation coefficient using sunflower oil as a coating of micro bubbles. These carriers were stable for periods of time that are long enough for clinical applications even when regular air is used as the gas phase. Improved

  19. Evaluation of stability and size distribution of sunflower oil-coated micro bubbles for localized drug delivery

    Directory of Open Access Journals (Sweden)

    Filho WalterDuartedeAraujo

    2012-09-01

    Full Text Available Abstract Background Micro bubbles were initially introduced as contrast agents for ultrasound examinations as they are able to modify the signal-to-noise ratio in imaging, thus improving the assessment of clinical information on human tissue. Recent developments have demonstrated the feasibility of using these bubbles as drug carriers in localized delivery. In micro fluidics devices for generation of micro bubbles, the bubbles are formed at interface of liquid gas through a strangulation process. A device that uses these features can produce micro bubbles with small size dispersion in a single step. Methods A T-junction micro fluidic device constructed using 3D prototyping was made for the production of mono dispersed micro bubbles. These micro bubbles use sunflower oil as a lipid layer. Stability studies for micro bubbles with diameters different generated from a liquid phase of the same viscosity were conducted to evaluate whether micro bubbles can be used as drug carriers. The biocompatibility of coating layer, the ability to withstand environmental pressure variations combined with echogenicity, are key factors that they can safely play the role of drug transporters. Results The normal distribution curve with small dispersion of the diameter of bubbles validates the process of generating micro bubbles with low value of variation coefficient, i.e., 0.381 at 1.90%. The results also showed the feasibility of using sunflower oil as the lipid matrix with stable population of bubbles over 217 minutes for micro bubbles with an average diameter of 313.04 μm and 121 minutes for micro bubbles with an average diameter of 73.74 μm, considering bubbles with air as gaseous phase. Conclusion The results indicate that the micro fluidic device designed can be used for producing micro bubbles with low variation coefficient using sunflower oil as a coating of micro bubbles. These carriers were stable for periods of time that are long enough for clinical

  20. Formation of tight junctions between neighboring podocytes is an early ultrastructural feature in experimental crescentic glomerulonephritis

    Directory of Open Access Journals (Sweden)

    Succar L

    2016-11-01

    Full Text Available Lena Succar,1 Ross A Boadle,2 David C Harris,1,3 Gopala K Rangan1,3 1Centre for Transplant and Renal Research, The Westmead Institute for Medical Research, The University of Sydney, 2Electron Microscopy Laboratory, Institute of Clinical Pathology and Medical Research, Westmead Hospital, 3Department of Renal Medicine, Westmead Hospital, Western Sydney Local Health District, Westmead, Sydney, NSW, Australia Purpose: In crescentic glomerulonephritis (CGN, the development of cellular bridges between podocytes and parietal epithelial cells (PECs triggers glomerular crescent formation. However, the sequential changes in glomerular ultrastructure in CGN are not well defined. This study investigated the time course of glomerular ultrastructure in experimental CGN. Methods: Transmission electron microscopy (TEM was performed using kidney samples from rats with nephrotoxic serum nephritis (NSN from day 1 to day 14. Morphometric analysis was conducted on randomly selected glomeruli captured on TEM digital images. Results: On day 1 of NSN, there was widespread formation of focal contacts between the cell bodies of neighboring podocytes, and tight junctions were evident at the site of cell-to-cell contact. This was confirmed by the increased expression of the tight junction molecule, zonula occludens-1 (ZO-1, which localized to the points of podocyte cell–cell body contact. On day 2, the interpodocyte distance decreased and the glomerular basement membrane thickness increased. Foot process effacement (FPE was segmental on day 3 and diffuse by day 5, accompanied by the formation of podocyte cellular bridges with Bowman’s capsule, as confirmed by a decrease in podocyte-to-PEC distance. Fibrinoid necrosis and cellular crescents were evident in all glomeruli by days 7 and 14. In vitro, the exposure of podocytes to macrophage-conditioned media altered cellular morphology and caused an intracellular redistribution of ZO-1. Conclusion: The formation of tight

  1. A revised geographical range for Liolaemus elongates Koslowsky, 1896 (Squamata: Liolaemini in Argentina: review of reported and new-data based distribution with new localities

    Directory of Open Access Journals (Sweden)

    Ignacio Minoli

    2013-12-01

    Full Text Available Estimating the effective geographical ranges of species is central to species-oriented conservation and management. In this paper, we review the geographical distribution of Liolaemus elongatus Koslowsky, 1896 with three new records for northern Chubut and southern Río Negro provinces, Argentina. Based on detailed locality records pooled from multiple data sources, including new records obtained for this study, we revise the range of L. elongatus sensu stricto and provide geographical distribution maps comparing the previously recognized range to that proposed herein. Our results show that L. elongatus possesses a much more limited geographic distribution than previously thought, being restricted to areas south of 38°S latitude; the newly proposed range is merely half the species formerly recognized geographical distribution.

  2. [Extra skeletal Ewing's sarcoma. Report of two cases. Ultrastructural study of one case (author's transl)].

    Science.gov (United States)

    Krulik, M; Brechot, J M; de Saint-Maur, P; Lecomte, D; Mougeot-Martin, M; Audebert, A A; Zylberait, D; Debray, J

    The authors report two cases of extra skeletal Ewing's sarcoma. The first case concerns a 26 years old woman presenting a tumor at the level of the sacrum area, locally recurrent, metastazing to the lungs and the lumbar column, despite of radiotherapy and chemotherapy and leading to death after a course of 18 months. The second one is that of a 30 years old man bearing a tumor of the shoulder area probably already metastazed to bones, rapidly recurrent and metastazing to the lungs and cause of death after 9 months in spite of intensive therapy. About these 2 observations a review of the literature of the cases of extra skeletal Ewing's sarcoma is done. Whatever nosologic discussion it seems that Ewing's sarcoma may present essentially as a tumor of soft tissues. An ultrastructural study has been performed in the second case. The findings are similar to those reported in Ewing's sarcoma.

  3. Accumulation of enriched uranium UO2F2 in ultrastructure as studied by electron microscopic autoradiography

    International Nuclear Information System (INIS)

    Zhu Shoupeng; Wang Yuanchang

    1992-01-01

    A study was made on the retention of soluble enriched uranium UO 2 F 2 in ultrastructure by electron microscopic autoradiography. The early dynamic accumulation of radioactivity in the body showed that enriched uranium UO 2 F 2 was mainly localized in kidneys, especially accumulated in epithelial cells of proximal convoluted tubules leading to degeneration and necrosis of the tubules. In liver cells, enriched uranium UO 2 F 2 at first deposited in nuclei of the cells and in soluble proteins of the plasma, and later accumulated selectively in mitochondria and lysosomes. On electron microscopic autoradiographic study it was shown that the dynamic retention of radioactivity of enriched uranium UO 2 F 2 in skeleton increased steadily through the time period of exposure. Enriched uranium UO 2 F 2 chiefly deposited in nuclei and mitochondria of osteoblasts as well as of osteoclasts

  4. Stereomicroscopic and ultrastructural characterization of propionitrile-induced duodenal ulcer in the rat

    DEFF Research Database (Denmark)

    Poulsen, Steen Seier

    1978-01-01

    Acute duodenal ulcer produced by subcutaneous injection of propionitrile in rats was studied by stereo, light, and electron microscopy in order to gain insight into the localization and mechanism of initial cell injury. Stereomicroscopy revealed an initial fissuring and splitting of the tips...... of the villus folds within 4 hours after two injections of propionitrile. This was followed by sloughing of the epithelium, shortening and effacement of the villus folds, and within 24 hours the appearance of discrete ulcers in the mucosa of the proximal duodenum. In most of the rats, two ulcers developed......: the first and larger ulcer was on the antimesenteric side of the duodenum, and the other, a small and more superficial one, was on the opposite wall. Ultrastructural lesions appeared in the absorptive epithelial cells of the proximal duodenum within 5 hours following a single dose of propionitrile...

  5. Ultrastructural and Energy dispersive analysis of inorganic inclusions in a muscle biopsy

    International Nuclear Information System (INIS)

    Dodson, R.F.; Castillo-Mozun, P.; Hieger, L.R.; Williams, M.G. Jr.

    1981-01-01

    A muscle biopsy that, by light microscopy, exhibited mild atrophy consistent with chronic denervating disease was submitted for ultrastructural analysis. Inorganic structures within the tissue were defined by energy dispersive analysis as aluminosilicates, magnesium silicates, and iron deposits. These structures were localized in the interstitial (intercollagenous) area and in high concentrations within degenerated muscle bundles. An alteration of the blood/muscle barrier has obviously occurred; however, the extent to which the end result commonly occurs in humans is unknown. Clarification of the question raised by this observation will have to be derived from animal studies, and clinicians must have an awareness of the need for electron microscopy/energy-dispersive x-ray analysis in muscle biopsies from patients with similar therapeutic backgrounds

  6. Relation of immediate and delayed thallium-201 distribution to localization of iodine-125 antimyosin antibody in acute experimental myocardial infarction

    International Nuclear Information System (INIS)

    Khaw, B.A.; Strauss, H.W.; Pohost, G.M.; Fallon, J.T.; Katus, H.A.; Haber, E.

    1983-01-01

    Thallium-201 (TI-201) distribution in acute experimental myocardial infarction (MI) (n . 18) was compared with cardiac-specific antimyosin Fab (AM-Fab) uptake, a specific marker for myocardial necrosis. When antimyosin was injected 4 hours after ligation with TI-201 administered 23 hours 55 minutes later and measurement of myocardial distribution determined 5 minutes after intravenous administration of TI-201, (1) TI-201 distribution closely correlated with microsphere regional blood flow, and (2) an inverse exponential relation to iodine-125 (I-125) AM-Fab uptake was apparent. In another group of 4 animals, TI-201 and AM-Fab were administered intravenously 4 hours after MI, and 36 hours later myocardial distribution was measured. This delayed TI-201 distribution had a close inverse linear correlation with I-125 AM-Fab uptake. This inverse linear relation also was apparent in 28-hour-old MIs in dogs (n . 4) where collateral circulation had been established. TI-201 was administered intravenously at 27 hours after MI, and TI-201 distribution was determined 1 hour later. The present study demonstrated that whereas immediate TI-201 distribution is flow-limited, delayed TI-201 distribution is a marker of cell viability which, due to prolonged circulation time and redistribution, is not flow-limited

  7. Influence of regional and local topography on the distribution of polymetallic nodules in Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Kodagali, V.N.

    of polymetallic nodules with a patchy distribution. Areas with less relief have lesser abundance but a regular distribution. North-south topographic profiles have a smoother sea floor than the east-west ones. Near the minor faults, the abundance is high. Mn, Ni...

  8. Modelling local distribution of an Arctic dwarf shrub indicates an important role for remote sensing of snow cover

    NARCIS (Netherlands)

    Beck, PSA; Kalmbach, E; Joly, D; Stien, A; Nilsen, L

    2005-01-01

    Despite the intensive research effort directed at predicting the effects of climate change on plants in the Arctic, the impact of environmental change on species' distributions remains difficult to quantify. Predictive habitat distribution models provide a tool to predict the geographical

  9. Effect of the irradiance distribution from light curing units on the local micro-hardness of the surface of dental resins.

    Science.gov (United States)

    Haenel, Thomas; Hausnerová, Berenika; Steinhaus, Johannes; Price, Richard B T; Sullivan, Braden; Moeginger, Bernhard

    2015-02-01

    An inhomogeneous irradiance distribution from a light-curing unit (LCU) can locally cause inhomogeneous curing with locally inadequately cured and/or over-cured areas causing e.g. monomer elution or internal shrinkage stresses, and thus reduce the lifetime of dental resin based composite (RBC) restorations. The aim of the study is to determine both the irradiance distribution of two light curing units (LCUs) and its influence on the local mechanical properties of a RBC. Specimens of Arabesk TOP OA2 were irradiated for 5, 20, and 80s using a Bluephase® 20i LCU in the Low mode (666mW/cm(2)), in the Turbo mode (2222mW/cm(2)) and a Celalux® 2 (1264mW/cm(2)). The degree of conversion (DC) was determined with an ATR-FTIR. The Knoop micro-hardness (average of five specimens) was measured on the specimen surface after 24h of dark and dry storage at room temperature. The irradiance distribution affected the hardness distribution across the surface of the specimens. The hardness distribution corresponded well to the inhomogeneous irradiance distributions of the LCU. The highest reaction rates occurred after approximately 2s light exposure. A DC of 40% was reached after 3.6 or 5.7s, depending on the LCU. The inhomogeneous hardness distribution was still evident after 80s of light exposure. The irradiance distribution from a LCU is reflected in the hardness distribution across the surface. Irradiance level of the LCU and light exposure time do not affect the pattern of the hardness distribution--only the hardness level. In areas of low irradiation this may result in inadequate resin polymerization, poor physical properties, and hence premature failure of the restorations as they are usually much smaller than the investigated specimens. It has to be stressed that inhomogeneous does not necessarily mean poor if in all areas of the restoration enough light intensity is introduced to achieve a high degree of cure. Copyright © 2014 Academy of Dental Materials. Published by

  10. Ultrastructure of Withania Somnifera (L.) Dunal pollen grains

    International Nuclear Information System (INIS)

    Alwadie, H.M.

    2002-01-01

    Light, scanning and transmission electron microscopy were used to study the morphology and ultrastructure of Withania Somnifera (L.) Dunall pollen grains. Light microscopic examination revealed that the pollen grains are tri- or tetrazonocoplate grains, approximately as long as broad, measuring 29-um. Scanning electron microscopic observation showed that surface sculpturing of the pollen is scarbate-granulate. Ultrathin sections as examined by transmission electron microscope showed that the pollen contained numerous starch grains, lipid droplets, endoplasmic reticulum and vesicles of dictyosomes. Two layers of the pollen wall were also distinguished, the outer wall (exine) divided into ektexine and endexine as well as the inner layer (intine). The nutritive values of Withania pollen are discussed. The importance of studying the ultrastructure of pollen grains as a new tool in palynology is also discussed. (author)

  11. Ultrastructure and mitochondrial numbers in pre- and postpubertal pig oocytes

    DEFF Research Database (Denmark)

    Pedersen, Hanne Skovsgaard; Callesen, Henrik; Løvendahl, Peter

    2016-01-01

    Prepubertal pig oocytes are associated with lower developmental competence. The aim of this experiment was to conduct an exhaustive survey of oocyte ultrastructure and to use a design-unbiased stereological approach to quantify the numerical density and total number of mitochondria in oocytes...... with different diameters from pre- and postpubertal pigs. The ultrastructure of smaller prepubertal immature oocytes indicated active cells in close contact with cumulus cells. The postpubertal oocytes were more quiescent cell types. The small prepubertal oocytes had a lower total mitochondrial number......, but no differences were observed in mitochondrial densities between groups. Mature postpubertal oocytes adhered to the following characteristics: presence of metaphase II, lack of contact between cumulus cells and oocyte, absence of rough endoplasmic reticulum and Golgi complexes, peripheral location of cortical...

  12. Axoglial contacts in the area postrema of the cat - An ultrastructural study

    Science.gov (United States)

    Damelio, Fernando E.; Gibbs, Michael A.; Mehler, William R.; Philpott, Delbert E.; Savage, Wayne

    1986-01-01

    Axoglial contacts were observed in an ultrastructural study of the area postrema of the cat. According to the disposition of the electron-dense projections attached to the adjoining membranes these contacts were classified as symmetrical or asymmetrical. The axon profiles contained aggregations of clear vesicles randomly distributed or grouped in clusters adjacent to the electron-dense projections. Dense core vesicles were occasionally seen. The neuroglial profiles were either astrocytic or ependymoglial in nature. The astrocytes showed a clear cytoplasm, polymorphous vesicles, mitochondria, glycogen granules, and bundles of filaments. The ependymal cells, in contrast, had a more electron-dense and granular appearance, tubular structures, irregular vesicular formations, profiles of smooth reticuloendoplasm, and filaments grouped in bundles or isolated in the cytoplasm. The possibility that these contacts might play a role in the chemical transfer from neurons to glial cells is discussed on the basis of existing biochemical data.

  13. Cytogenetical and ultrastructural effects of copper on root meristem cells of Allium sativum L.

    Science.gov (United States)

    Liu, Donghua; Jiang, Wusheng; Meng, Qingmin; Zou, Jin; Gu, Jiegang; Zeng, Muai

    2009-04-01

    Different copper concentrations, as well as different exposure times, were applied to investigate both cytogenetical and ultrastructural alterations in garlic (Allium sativum L.) meristem cells. Results showed that the mitotic index decreased progressively when either copper concentration or exposure time increased. C-mitosis, anaphase bridges, chromosome stickiness and broken nuclei were observed in the copper treated root tip cells. Some particulates containing the argyrophilic NOR-associated proteins were distributed in the nucleus of the root-tip cells and the amount of this particulate material progressively increased with increasing exposure time. Finally, the nucleolar material was extruded from the nucleus into the cytoplasm. Also, increased dictyosome vesicles in number, formation of cytoplasmic vesicles containing electron dense granules, altered mitochondrial shape, disruption of nuclear membranes, condensation of chromatin material, disintegration of organelles were observed. The mechanisms of detoxification and tolerance of copper are briefly discussed.

  14. Ultrastructural study of myelinating cells and sub-pial astrocytes in developing rat spinal cord.

    Science.gov (United States)

    Nagashima, K

    1979-12-01

    The anterior funiculus of the spinal cervical cord of post-natal rats was examined ultrastructurally. The myelinating cells found one day after brith contained a large amount of evenly distributed ribosomes up to the outer tongue of mesaxons, representing the cytoplasmic density. These cells were separated by astrocytic processes from the pial basement membrane, even when they were located on the pial surface. Astrocytes contained glial fibrils from one day onwards and often attached their processes to the pial basement membrane. Although the cytoplasmic processes of astrocytes occasionally wrapped axons, they were never shown to form the initial layer of myelin sheaths. However, the tenuous processes of the sub-pial astrocytes were occasionally rolled in myelin lamellae, as if a part of the myelin sheaths was constructed by astrocytic processes. The interpretation for this finding is discussed in relation to function and potency of the astrocytes, and variations and anomalies of nervous ontogeny.

  15. Enzymatic and ultrastructural study of lysosomes in rats bearing radiation-induced thyroid follicular carcinoma

    International Nuclear Information System (INIS)

    Starling, J.R.; Clifton, K.H.; Norback, D.H.

    1981-01-01

    Radiation-induced well-differentiated and poorly differentiated follicular thyroid cancers were transplanted into the intrascapular fat pads of male Fisher 144 rats. The tumors grew in the recipient rats and after a time interval were removed and studied along with normal rat thyroids for lysosomal activity and ultrastructural characteristics. Plasma from experimental and control rats was also studied for lysosomal activity. Rats with radiation-induced thyroid carcinoma had a decrease in growth rate compared with normal rats. There was no significant increase in plasma lysosomal enzymes in the experimental rats. Well-differentiated thyroid carcinomatous tissue showed increased total activities of lysosomal enzymes as well as a difference in subcellular distribution compared with normal and poorly differentiated carcinomatous tissue. Electron microscopy of normal and carcinomatous tissue demonstrated the greatest number of lysosomes in the well-differentiated carcinoma and the fewest in the poorly differentiated carcinoma

  16. Ultrastructural Changes in Cherimoya Fruit Injured by Chilling

    OpenAIRE

    Gutierrez, Margarita; Mar Sola, Maria del; Pascual, Luis; Rodriguez-Garcia, Maria Isabel; Vargas, Alberto M.

    1992-01-01

    Cherimoya (Annona cherimola Mill.) is an important fruit crop that is grown in the South of Spain. Ultrastructural modifications of cherimoya fruit were studied after low-temperature storage. When cherimoya was stored at 4 oc for 6 days, the starch grains did not suffer degradation and the cell walls remained intact. The membrane systems were severely damaged , result ing in a loss of cell compartmentalization. Cherimoya rewarmed to 22 0 C after 9 days of low temperature storage is not able t...

  17. Ultrastructural muscle and neuro-muscular junction alterations in polymyositis

    Directory of Open Access Journals (Sweden)

    L. L. Babakova

    2012-01-01

    Full Text Available Ultrastructural analysis of 7 biopsies from m.palmaris longus and m.deltoideus in patients with confirmed polymyositis revealed alterationand degeneration of muscle fibers and anomalies of neuro-muscular junction (NMJ. The NMJ abnormalities and following denervation ofmuscle fibers in polymyositis start with subsynaptic damages. The occurance of regeneration features in muscle fibers at any stage is characteristic for PM.

  18. Ultrastructural features of Mimulus aurantiacus (Scrophulariaceae) pollen tubes in vivo

    OpenAIRE

    Ekici,Nuran; Dane,Feruzan; Olgun,Göksel

    2009-01-01

    The aim of this study is to give information on ultrastructure of in vivo pollen tubes of Mimulus aurantiacus which were collected from the Botanical Garden of the University of California at Berkeley. Materials were prepared according to electron microscopy methods and examined under Zeiss electron microscope. Four zones were examined in the pollen tubes of Mimulus aurantiacus. APICAL ZONE: Mitochondria, smooth endoplasmic reticulum, rough endoplasmic reticulum, dictyosomes and secretory ves...

  19. Ultrastructure and cytochemistry of cardiac intramitochondrial glycogen.

    Science.gov (United States)

    Sótonyi, P; Somogyi, E; Nemes, A; Juhász-Nagy, S

    1976-01-01

    Authors have observed abnormalities of glycogen localization in cardiac muscle, after normothermic cardiac arrest. The identification of these intramitrochondrial particles as glycogen was confirmed by selective staining with periodic acid-lead citrat, periodic acid-thiosemicarbazide protein methods and by their selective removal from tissue sections by alfa-amylase. The intramitochondrial glycogen particles were of beta-type. Some intramitochondrial particles were surrounded by paired membranes which resulted from protrusion of parts of mitochondrial membrane.

  20. Ultrastructural alterations in adult Schistosoma mansoni caused by artemether

    Directory of Open Access Journals (Sweden)

    Shuhua Xiao

    2002-07-01

    Full Text Available Progress has been made over the last decade with the development and clinical use of artemether as an agent against major human schistosome parasites. The tegument has been identified as a key target of artemether, implying detailed studies on ultrastructural damage induced by this compound. We performed a temporal examination, employing a transmission electron microscope to assess the pattern and extent of ultrastructural alterations in adult Schistosoma mansoni harboured in mice treated with a single dose of 400 mg/kg artemether. Eight hours post-treatment, damage to the tegument and subtegumental structures was seen. Tegumental alterations reached a peak 3 days after treatment and were characterized by swelling, fusion of distal cytoplasma, focal lysis of the tegumental matrix and vacuolisation. Tubercles and sensory organelles frequently degenerated or collapsed. Typical features of subtegumental alterations, including muscle fibres, syncytium and parenchyma tissues, were focal or extensive lysis, vacuolisation and degeneration of mitochondria. Severe alterations were also observed in gut epithelial cells and vitelline cells of female worms. Our findings of artemether-induced ultrastructural alterations in adult S. mansoni confirm previous results obtained with juvenile S. mansoni and S. japonicum of different ages.

  1. Ultrastructural Changes in the Liver of Intravenous Heroin Addicts

    Directory of Open Access Journals (Sweden)

    Goran Ilić

    2010-02-01

    Full Text Available The ultrastructural research has a decisive role in gathering the knowledge on the liver’s response to the influence of some drugs. The aim of the study was to perform an ultrastructurai analysis of the liver in chronic intravenous heroin addicts.The study involved the autopsy conducted on 40 bodies of intravenous heroin addicts and 10 control autopsies. The liver tissue was fixed in glutaraldehyde and moulded with epon for investigation purposes of ultrastructural changes. The analysis was performed using the method of transmission electron microscopy.In the group of intravenous heroin addicts, the liver autopsy samples showed degenerative vesicular and fat changes, chronic active and persistent hepatitis, cirrhosis, reduction in the amount of glycogen in hepatocytes, as well as the Kupffer cell’s dominant hypertrophy. Various changes occur in organelles, plasma membrane of hepatocytes and biliary channels as well as in the nucleus.The most important ultrastructural findings include: hyperplasia and hypertrophy of the smooth endoplasmic reticulum, which is histologically proven vesicular degeneration of hepatocyte occurring as a result of the increased synthesis of enzymes of smooth endoplasmic reticulum due to chronic intravenous heroin intake, and the presence of continuous basal membrane followed by transformation of the sinusoids into capillaries (in the cases of chronic active hepatitis and cirrhosis which leads to a disorder of microcirculation and further progress of cirrhosis.

  2. Ultrastructural morphometry of parotid acinar cells following fractionated irradiation

    International Nuclear Information System (INIS)

    Grehn, A.-L.; Gustafsson, H.; Franzen, L.; Thornell, L.-E.; Henriksson, R.

    1997-01-01

    The aim of this study was to evaluate the long term effects on the ultrastructure of parotid glands after fractionated irradiation. The method implemented involved 5 x 6 Gy and 5 x 8 Gy, Monday to Friday 6 MV photons. By unilateral irradiation, the contralateral parotid gland served as a control. Although irradiation diminished the acinar cell density in light microscopic sections from 75 to 32% after 5 x 8 Gy of irradiation, ultrastructural morphometry could not detect any statistically significant differences in acinar cell size, nuclear size, nuclear density, granule area, mean granule size, or granule density. In general, greater differences were seen between rats receiving 30 or 40 Gy, on both the irradiated and the control side, than between the irradiated side and the control side. This was interpreted as due to differences in the nutritional state of the animals. This analysis concluded that individual acinar cells that survive irradiation seem not to be damaged in the long term when evaluated at the ultrastructural level. The study further stresses the importance of adequate sampling sizes and the use of adequate controls. (author)

  3. Ultrastructure of spermatozoa in cobia, Rachycentron canadum (Linnaeus, 1766).

    Science.gov (United States)

    Dhanasekar, Krishnamoorthy; Selvakumar, Narasimman; Munuswamy, Natesan

    2018-02-01

    Ultrastructure and development of spermatozoa in cobia, Rachycentron canadum are described. Sections through the testis show different developmental stages viz, Spermatocytes, spermatids and sperm. Spermatozoa of R. canadum exhibit the configuration of uniflagellated, anacrosomal Type I aquasperm, typical for externally fertilizing fish. Mature spermatozoon is seen with a prominent head and long cylindrical flagellum. Ultrastructure of sperm shows invaginated 'U' shaped nucleus and other organelles. The mitochondrial matrix is electron-dense with irregular arrangement of the cristae. The nucleus reveals a deep invagination (nuclear fossa) in which the centriolar complex is located. The centriolar complex lies inside the nuclear fossa and is composed of a proximal and a distal centriole. The two centrioles are placed perpendicular to each other. The flagellum has a typical eukaryotic organization (microtubule doublets 9 + 2 pattern) and measures around 36.21 ± 0.42 μm in length. This study for the first time provides a comprehensive detail on the ultrastructure and developmental process of sperm in cobia, R. canadum. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Influence of a transport current on the local magnetic field distribution in sintered YBa2Cu3Ox

    International Nuclear Information System (INIS)

    Zimmermann, P.; Keller, H.; Kuendig, W.; Puempin, B.; Savic, I.M.; Schneider, J.W.; Simmler, H.; Kaldis, E.; Rusiecki, S.

    1991-01-01

    The influence of a transport current on the magnetic flux-line distribution in sintered YBCO was studied by means of μSR. Pronounced differences between zero-field-cooled (ZFC) and field-cooled (FC) signals and irreversible behavior were observed. In the ZFC case even a small transport current (10 A/cm 2 ) tends to order irreversibly the inhomogeneous flux-line distribution considerably, suggesting a broad distribution of pinning barriers. However, for a FC sample no noticeable change in the flux distribution in the presence of a transport current (up to 40 A/cm 2 ) was detected, indicating that the FC state represents a stable flux-line configuration. (orig.)

  5. Do poorer people have poorer access to local resources and facilities? The distribution of local resources by area deprivation in Glasgow, Scotland☆

    Science.gov (United States)

    Macintyre, Sally; Macdonald, Laura; Ellaway, Anne

    2008-01-01

    It has commonly been suggested that in modern cities individual or household deprivation (for example, low income or education) is amplified by area level deprivation (for example, lack of jobs or good schools), in ways which damage the health of the poorest and increase health inequalities. The aim of this study was to determine the location of a range of resources and exposures by deprivation in a UK city. We examined the location of 42 resources in Glasgow City, Scotland, in 2005–2006, by quintile of small area deprivation. Measures included number per 1000 population, network distance to nearest resource, and percentage of data zones containing at least one of each type of resource. Twelve resources had higher density in, and/or were closer to or more common in, more deprived neighbourhoods: public nurseries, public primary schools, police stations, pharmacies, credit unions, post offices, bus stops, bingo halls, public swimming pools, public sports centres, outdoor play areas, and vacant and derelict land/buildings. Sixteen had higher density in, and/or were closer to, or more common in, more affluent neighbourhoods: public secondary schools, private schools, banks, building societies, museums/art galleries, railway stations, subway stations, tennis courts, bowling greens, private health clubs, private swimming pools, colleges, A & E hospitals, parks, waste disposal sites, and tourist attractions. Private nurseries, Universities, fire stations, general, dental and ophthalmic practices, pawn brokers, ATMs, supermarkets, fast food chains, cafes, public libraries, golf courses, and cinemas showed no clear pattern by deprivation. Thus it appears that in the early 21st century access to resources does not always disadvantage poorer neighbourhoods in the UK. We conclude that we need to ensure that theories and policies are based on up-to-date and context-specific empirical evidence on the distribution of neighbourhood resources, and to engage in further research

  6. Do poorer people have poorer access to local resources and facilities? The distribution of local resources by area deprivation in Glasgow, Scotland.

    Science.gov (United States)

    Macintyre, Sally; Macdonald, Laura; Ellaway, Anne

    2008-09-01

    It has commonly been suggested that in modern cities individual or household deprivation (for example, low income or education) is amplified by area level deprivation (for example, lack of jobs or good schools), in ways which damage the health of the poorest and increase health inequalities. The aim of this study was to determine the location of a range of resources and exposures by deprivation in a UK city. We examined the location of 42 resources in Glasgow City, Scotland, in 2005-2006, by quintile of small area deprivation. Measures included number per 1000 population, network distance to nearest resource, and percentage of data zones containing at least one of each type of resource. Twelve resources had higher density in, and/or were closer to or more common in, more deprived neighbourhoods: public nurseries, public primary schools, police stations, pharmacies, credit unions, post offices, bus stops, bingo halls, public swimming pools, public sports centres, outdoor play areas, and vacant and derelict land/buildings. Sixteen had higher density in, and/or were closer to, or more common in, more affluent neighbourhoods: public secondary schools, private schools, banks, building societies, museums/art galleries, railway stations, subway stations, tennis courts, bowling greens, private health clubs, private swimming pools, colleges, A & E hospitals, parks, waste disposal sites, and tourist attractions. Private nurseries, Universities, fire stations, general, dental and ophthalmic practices, pawn brokers, ATMs, supermarkets, fast food chains, cafes, public libraries, golf courses, and cinemas showed no clear pattern by deprivation. Thus it appears that in the early 21st century access to resources does not always disadvantage poorer neighbourhoods in the UK. We conclude that we need to ensure that theories and policies are based on up-to-date and context-specific empirical evidence on the distribution of neighbourhood resources, and to engage in further research on

  7. The EM autoradiographic distribution of label in tissue blocks of pallidum incorporating [3H]-Leu-enkephalin and [3H]-naloxone in vitro

    International Nuclear Information System (INIS)

    Csillag, A.; Hajos, F.

    1985-01-01

    The distribution of radioactivity in pallidal tissue blocks incubated in the presence of either a tritiated enkephalin analogue or [ 3 H]-naloxone, was examined using EM autoradiography. The quantitative evaluation was based on the principle of proportional grain counting. The results showed a preferential accumulating of silver grains over dendrites in the enkephalin-labelled tissue. Following naloxone-labelling, a slight enrichment of grains over axonal elements was found. The findings provide ultrastructural support for previous biochemical data which suggested that different types of opiate binding sites have different tissue localizations. (author)

  8. Iris ultrastructure in patients with synechiae as revealed by in vivo laser scanning confocal microscopy : In vivo iris ultrastructure in patients with Synechiae by Laser Scanning Confocal Microscopy.

    Science.gov (United States)

    Li, Ming; Cheng, Hongbo; Guo, Ping; Zhang, Chun; Tang, Song; Wang, Shusheng

    2016-04-26

    Iris plays important roles in ocular physiology and disease pathogenesis. Currently it is technically challenging to noninvasively examine the human iris ultrastructure in vivo. The purpose of the current study is to reveal human iris ultrastructure in patients with synechiae by using noninvasive in vivo laser scanning confocal microscopy (LSCM). The ultrastructure of iris in thirty one patients, each with synechiae but transparent cornea, was examined by in vivo LSCM. Five characteristic iris ultrastructures was revealed in patients with synechiae by in vivo LSCM, which include: 1. tree trunk-like structure; 2. tree branch/bush-like structure; 3. Fruit-like structure; 4. Epithelioid-like structure; 5. deep structure. Pigment granules can be observed as a loose structure on the top of the arborization structure. In iris-associated diseases with Tyndall's Phenomenon and keratic precipitates, the pigment particles are more likely to fall off from the arborization structure. The ultrastructure of iris in patients with synechiae has been visualized using in vivo LSCM. Five iris ultrastructures can be clearly observed, with some of the structures maybe disease-associated. The fall-off of the pigment particles may cause the Tyndall's Phenomenon positive. In vivo LSCM provides a non-invasive approach to observe the human iris ultrastructure under certain eye disease conditions, which sets up a foundation to visualize certain iris-associated diseases in the future.

  9. Fuel-element temperature nonstationary distribution caused by local pulsations of the factor of heat transfer to a coolant

    International Nuclear Information System (INIS)

    Pupko, V.Ya.

    1978-01-01

    The equation of nonstationary heat transfer caused by the appearance of a local pulse jump in the factor of heat transfer to a coolant is solved analytically for a cylindrical fuel element. The problem solution is generalized to a case of the periodically pulsating factor of heat transfer according to its value in an arbitrary point of the fuel element surface

  10. Spatial clustering and halo occupation distribution modelling of local AGN via cross-correlation measurements with 2MASS galaxies

    Science.gov (United States)

    Krumpe, Mirko; Miyaji, Takamitsu; Coil, Alison L.; Aceves, Hector

    2018-02-01

    We present the clustering properties and halo occupation distribution (HOD) modelling of very low redshift, hard X-ray-detected active galactic nuclei (AGN) using cross-correlation function measurements with Two-Micron All Sky Survey galaxies. Spanning a redshift range of 0.007 2MASS galaxies.

  11. Ultrastructural and Molecular Characterisation of an Heterosporis-Like Microsporidian in Australian Sea Snakes (Hydrophiinae.

    Directory of Open Access Journals (Sweden)

    Amber K Gillett

    Full Text Available Four sea snakes (two Hydrophis major, one Hydrophis platurus, one Hydrophis elegans were found washed ashore on different beaches in the Sunshine Coast region and Fraser Island in Queensland, Australia between 2007-2013. Each snake had multiple granulomas and locally extensive regions of pallor evident in the hypaxial and intercostal musculature along the body. Lesions in two individuals were also associated with vertebral and rib fractures. Histological examination revealed granulomas scattered throughout skeletal muscle, subcutaneous adipose tissue and fractured bone. These were composed of dense aggregates of microsporidian spores surrounded by a mantle of macrophages. Sequences (ssrRNA were obtained from lesions in three sea snakes and all revealed 99% similarity with Heterosporis anguillarum from the Japanese eel (Anguillarum japonica. However, ultrastructural characteristics of the organism were not consistent with those of previous descriptions. Electron microscopic examination of skeletal muscle revealed large cysts (not xenomas bound by walls of fibrillar material (Heterosporis-like sporophorocyst walls were not detected. The cysts contained numerous mature microsporidian spores arranged in small clusters, sometimes apparently within sporophorous vesicles. The microspores were monomorphic, oval and measured 2.5-3.0 μm by 1.6-1.8 μm. They contained isofilar polar filaments with 11 (infrequently 9-12 coils arranged in two ranks. This is the first published report of a microsporidian infection in hydrophiid sea snakes. This discovery shows microsporidia with molecular affinities to Heterosporis anguillarum but ultrastructural characters most consistent with the genus Pleistophora (but no hitherto described species. Further studies are required to determine whether the microsporidian presented here belongs to the genus Heterosporis, or to a polymorphic species group as suggested by the recognition of a robust Pleistophora

  12. Localized iron supply triggers lateral root elongation in Arabidopsis by altering the AUX1-mediated auxin distribution.

    Science.gov (United States)

    Giehl, Ricardo F H; Lima, Joni E; von Wirén, Nicolaus

    2012-01-01

    Root system architecture depends on nutrient availability, which shapes primary and lateral root development in a nutrient-specific manner. To better understand how nutrient signals are integrated into root developmental programs, we investigated the morphological response of Arabidopsis thaliana roots to iron (Fe). Relative to a homogeneous supply, localized Fe supply in horizontally separated agar plates doubled lateral root length without having a differential effect on lateral root number. In the Fe uptake-defective mutant iron-regulated transporter1 (irt1), lateral root development was severely repressed, but a requirement for IRT1 could be circumvented by Fe application to shoots, indicating that symplastic Fe triggered the local elongation of lateral roots. The Fe-stimulated emergence of lateral root primordia and root cell elongation depended on the rootward auxin stream and was accompanied by a higher activity of the auxin reporter DR5-β-glucuronidase in lateral root apices. A crucial role of the auxin transporter AUXIN RESISTANT1 (AUX1) in Fe-triggered lateral root elongation was indicated by Fe-responsive AUX1 promoter activities in lateral root apices and by the failure of the aux1-T mutant to elongate lateral roots into Fe-enriched agar patches. We conclude that a local symplastic Fe gradient in lateral roots upregulates AUX1 to accumulate auxin in lateral root apices as a prerequisite for lateral root elongation.

  13. A comparison of neuronal growth cone and cell body membrane: electrophysiological and ultrastructural properties.

    Science.gov (United States)

    Guthrie, P B; Lee, R E; Kater, S B

    1989-10-01

    This study investigated a broad set of general electrophysiological and ultrastructural features of growth cone and cell body membrane of individual neurons where membrane from different regions of the same neuron can be directly compared. Growth cones were surgically isolated from identified adult Helisoma neurons in culture and compared with the cell body using whole-cell patch-clamp recording techniques. All isolated growth cones generated overshooting regenerative action potentials. Five neurons (buccal neurons B4, B5, and B19; pedal neurons P1 and P5) were selected that displayed distinctive action potential waveforms. In all cases, the growth cone action potential was indistinguishable from the cell body action potential and different from growth cones from other identified neurons. Two of these neurons (B5 and B19) were studied further using voltage-clamp procedures; growth cones and cell bodies again revealed major similarities within one neuron type and differences between neuron types. The only suggested difference between the growth cone and cell body was an apparent reduction in the magnitude of the A-current in the growth cone. Peak inward and outward current densities, as with other electrophysiological features, were different between neuron types, but were, again, similar between the growth cone and the cell body of the same neuron. Freeze-fracture analysis of intramembraneous particles (IMPs) was also performed on identified regions of the same neuron in culture. Both the density and the size distribution of IMPs were the same in growth cone, cell body, and neurite membranes. In these general electrophysiological and ultrastructural characteristics, therefore, growth cone membranes appear to retain the identity of the parent neuron cell body membrane.

  14. Towards A Complete Census of the Compton-thick AGN population and the NH Distribution of AGN in the Local Universe.

    Science.gov (United States)

    Annuar, A.

    2015-09-01

    We present updated results from an ongoing project to establish the most unbiased census of the Compton- thick active galactic nucleus (CTAGN) population and the intrinsic column density (NH) distribution of the overall AGN population in the local universe, using a sample of mid-infrared (mid-IR) selected AGN within 15 Mpc. We find that 20% of the AGN in the sample are bona-fide CTAGN based upon hard X-ray studies (E > 10 keV). More candidates are then selected using multiwavelength techniques, i.e. mid-IR:X-ray and optical [OIII]5007:X-ray flux ratios. Based on these analyses along with evidence from previous literature, we initially find a further 25% of potential candidates. We then observed two of these candidates, NGC 5643 and NGC 3486, using NuSTAR and is able to confirm the former as a CTAGN and rule out the latter as an obscured AGN. This constrains the total CTAGN population in the sample to 25-40%, though it could potentially be as high as 65% accounting for those that still lack data. Finally, we use these results to estimate the intrinsic NH distribution of the local AGN population. Two more of our CTAGN candidates are scheduled to be observed by NuSTAR, bringing the completeness of hard X-ray energy data of the sample to 65%. This work provides a well-defined local benchmark for AGN unification studies.

  15. Nuclear distribution of the Trypanosoma cruzi RNA Pol I subunit RPA31 during growth and metacyclogenesis, and characterization of its nuclear localization signal.

    Science.gov (United States)

    Canela-Pérez, Israel; López-Villaseñor, Imelda; Cevallos, Ana María; Hernández, Roberto

    2018-03-01

    Trypanosoma cruzi is the aetiologic agent of Chagas disease. Our research group studies ribosomal RNA (rRNA) gene transcription and nucleolus dynamics in this species of trypanosomes. RPA31 is an essential subunit of RNA polymerase I (Pol I) whose presence is apparently restricted to trypanosomes. Using fluorescent-tagged versions of this protein (TcRPA31-EGFP), we describe its nuclear distribution during growth and metacyclogenesis. Our findings indicate that TcRPA31-EGFP alters its nuclear presence from concentrated nucleolar localization in exponentially growing epimastigotes to a dispersed granular distribution in the nucleoplasm of stationary epimastigotes and metacyclic trypomastigotes. These changes likely reflect a structural redistribution of the Pol I transcription machinery in quiescent cellular stages where downregulation of rRNA synthesis is known to occur. In addition, and related to the nuclear internalization of this protein, the presence of a classical bipartite-type nuclear localization signal was identified towards its C-terminal end. The functionality of this motif was demonstrated by its partial or total deletion in recombinant versions of the tagged fluorescent protein. Moreover, ivermectin inhibited the nuclear localization of the labelled chimaera, suggesting the involvement of the importin α/β transport system.

  16. Micro-macro model for prediction of local temperature distribution in heterogeneous and two-phase media

    Directory of Open Access Journals (Sweden)

    Furmański Piotr

    2014-09-01

    Full Text Available Heat flow in heterogeneous media with complex microstructure follows tortuous path and therefore determination of temperature distribution in them is a challenging task. Two-scales, micro-macro model of heat conduction with phase change in such media was considered in the paper. A relation between temperature distribution on the microscopic level, i.e., on the level of details of microstructure, and the temperature distribution on the macroscopic level, i.e., on the level where the properties were homogenized and treated as effective, was derived. The expansion applied to this relation allowed to obtain its more simplified, approximate form corresponding to separation of micro- and macro-scales. Then the validity of this model was checked by performing calculations for 2D microstructure of a composite made of two constituents. The range of application of the proposed micro-macro model was considered in transient states of heat conduction both for the case when the phase change in the material is present and when it is absent. Variation of the effective thermal conductivity with time was considered and a criterion was found for which application of the considered model is justified.

  17. Distribution, management and diversity of yam local varieties in Brazil: a study on Dioscorea alataL.

    Directory of Open Access Journals (Sweden)

    MVBM Siqueira

    Full Text Available Widely spread in the tropics, yams were introduced into Brazil during the colonial period and are currently grown throughout the country. Despite its importance as a pharmacological and food source, there is a lack of studies describing how and where this tuber is grown in Brazil. The aim of this study was to provide an overview of the cultivation and distribution of Dioscorea alata in different Brazilian regions. A total of 63 farmers were visited in different municipalities and communities in four regions in the country: South, Southeast, Northeast and Midwest. Semi-structured interviews were conducted to collect socio-economic, use, management and diversity data for this crop. The majority of interviewers were men, married, with children, using retirement benefits and agriculture as income and family labour as the main support in the yam cultivation. A wide distribution of this species was found, with the occurrence of D. alata in the four sampled regions. A variety of vernacular names for this species was collected, differing according to the region where it is cultivated. Most farmers cultivate yams in fields, however an increased usage of home gardens for the cultivation of this tuber was found. Also, most farmers cultivate yams in association with other crops in areas of different sizes and slash and burn practices, although mostly disappearing, are still being used by many farmers. The results of this study provide more concrete data on the distribution and diversity of this important crop.

  18. Abundance and Summer Distribution of a Local Stock of Black Sea Bottlenose Dolphins, Tursiops truncatus (Cetacea, Delphinidae, in Coastal Waters near Sudak (Ukraine, Crimea

    Directory of Open Access Journals (Sweden)

    Gladilina E. V.

    2016-02-01

    Full Text Available The first assessment of abundance of a local population of bottlenose dolphins in the Black Sea (near the Sudak coast in 2011–2012 has been conducted: the results of a mark-recapture study of photo identified animals were complemented by a vessel line transect survey. The overall abundance of a population was estimated at between 621 ± 198 and 715 ± 267 animals (Chapman and Petersen estimates, and the majority of members of the population were recorded in the surveyed area. The summer range covered the area of a few hundred square kilometers, similar to migrating coastal stocks in other world regions. The greatest density of distribution was observed in August in sea 45–60 m deep; in addition, frequent approaches to the coastline are usual for dolphins of this stock. These trends in distribution may be partly explained by distribution of prey. Interaction with sprat trawling fisheries can be a factor shaping the local population structure. Coastal waters of Sudak and adjoining sea areas are an important habitat for bottlenose dolphins in the northern Black Sea, significant for their conservation.

  19. Evolution of biological sequences implies an extreme value distribution of type I for both global and local pairwise alignment scores.

    Science.gov (United States)

    Bastien, Olivier; Maréchal, Eric

    2008-08-07

    Confidence in pairwise alignments of biological sequences, obtained by various methods such as Blast or Smith-Waterman, is critical for automatic analyses of genomic data. Two statistical models have been proposed. In the asymptotic limit of long sequences, the Karlin-Altschul model is based on the computation of a P-value, assuming that the number of high scoring matching regions above a threshold is Poisson distributed. Alternatively, the Lipman-Pearson model is based on the computation of a Z-value from a random score distribution obtained by a Monte-Carlo simulation. Z-values allow the deduction of an upper bound of the P-value (1/Z-value2) following the TULIP theorem. Simulations of Z-value distribution is known to fit with a Gumbel law. This remarkable property was not demonstrated and had no obvious biological support. We built a model of evolution of sequences based on aging, as meant in Reliability Theory, using the fact that the amount of information shared between an initial sequence and the sequences in its lineage (i.e., mutual information in Information Theory) is a decreasing function of time. This quantity is simply measured by a sequence alignment score. In systems aging, the failure rate is related to the systems longevity. The system can be a machine with structured components, or a living entity or population. "Reliability" refers to the ability to operate properly according to a standard. Here, the "reliability" of a sequence refers to the ability to conserve a sufficient functional level at the folded and maturated protein level (positive selection pressure). Homologous sequences were considered as systems 1) having a high redundancy of information reflected by the magnitude of their alignment scores, 2) which components are the amino acids that can independently be damaged by random DNA mutations. From these assumptions, we deduced that information shared at each amino acid position evolved with a constant rate, corresponding to the

  20. Evolution of biological sequences implies an extreme value distribution of type I for both global and local pairwise alignment scores

    Directory of Open Access Journals (Sweden)

    Maréchal Eric

    2008-08-01

    Full Text Available Abstract Background Confidence in pairwise alignments of biological sequences, obtained by various methods such as Blast or Smith-Waterman, is critical for automatic analyses of genomic data. Two statistical models have been proposed. In the asymptotic limit of long sequences, the Karlin-Altschul model is based on the computation of a P-value, assuming that the number of high scoring matching regions above a threshold is Poisson distributed. Alternatively, the Lipman-Pearson model is based on the computation of a Z-value from a random score distribution obtained by a Monte-Carlo simulation. Z-values allow the deduction of an upper bound of the P-value (1/Z-value2 following the TULIP theorem. Simulations of Z-value distribution is known to fit with a Gumbel law. This remarkable property was not demonstrated and had no obvious biological support. Results We built a model of evolution of sequences based on aging, as meant in Reliability Theory, using the fact that the amount of information shared between an initial sequence and the sequences in its lineage (i.e., mutual information in Information Theory is a decreasing function of time. This quantity is simply measured by a sequence alignment score. In systems aging, the failure rate is related to the systems longevity. The system can be a machine with structured components, or a living entity or population. "Reliability" refers to the ability to operate properly according to a standard. Here, the "reliability" of a sequence refers to the ability to conserve a sufficient functional level at the folded and maturated protein level (positive selection pressure. Homologous sequences were considered as systems 1 having a high redundancy of information reflected by the magnitude of their alignment scores, 2 which components are the amino acids that can independently be damaged by random DNA mutations. From these assumptions, we deduced that information shared at each amino acid position evolved with a

  1. Histopathological, Ultrastructural and Apoptotic Changes in Diabetic Rat Placenta

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    Mehmet Gül

    2015-09-01

    Full Text Available Background: The exchange of substances between mother and fetus via the placenta plays a vital role during development. A number of developmental disorders in the fetus and placenta are observed during diabetic pregnancies. Diabetes, together with placental apoptosis, can lead to developmental and functional disorders. Aims: Histological, ultrastructural and apoptotic changes were investigated in the placenta of streptozotocin (STZ induced diabetic rats. Study Design: Animal experimentation. Methods: In this study, a total of 12 female Wistar Albino rats (control (n=6 and diabetic (n=6 were used. Rats in the diabetic group, following the administration of a single dose of STZ, showed blood glucose levels higher than 200 mg/dL after 72 hours. When pregnancy was detected after the rats were bred, two pieces of placenta and the fetuses were collected on the 20th day of pregnancy by cesarean incision under ketamine/xylazine anesthesia from in four rats from the control and diabetic groups. Placenta tissues were processed for light microscopy and transmission electron microscopy (TEM. Hematoxylin-eosin (HE and periodic acid Schiff-diastase (PAS-D staining for light microscopic and caspase-3 staining for immunohistochemical investigations were performed for each placenta. Electron microscopy was performed on thin sections contrasted with uranyl acetate and lead nitrate. Results: Weight gain in the placenta and fetuses of diabetic rats and thinning of the decidual layer, thickening of the hemal membrane, apoptotic bodies, congestion in intervillous spaces, increased PAS-D staining in decidual cells and caspase-3 immunoreactivity were observed in the diabetic group. After the ultrastructural examination, the apoptotic appearance of the nuclei of trophoblastic cells, edema and intracytoplasmic vacuolization, glycogen accumulation, dilation of the endoplasmic reticulum and myelin figures were observed. In addition, capillary basement membrane thickening

  2. Surface topography and ultrastructural changes of mucinous carcinoma breast cells.

    Science.gov (United States)

    Voloudakis, G E; Baltatzis, G E; Agnantis, N J; Arnogianaki, N; Misitzis, J; Voloudakis-Baltatzis, I

    2007-01-01

    Mucinous carcinoma of the breast (MCB) is histologically classified into 2 groups: (1) pure MCB and (2) mixed MCB. Pure MCB carries a better diagnosis than mixed MCB. This research relates to the cell surface topography and ultrastructure of the cells in the above cases and aims to find the differences between them, by means of two methods: scanning electron microscopy (SEM) and transmission electron microscopy (TEM). For the SEM examination, it was necessary to initially culture the MCB tissues and then proceed with the usual SEM method. In contrast, for the TEM technique, MCB tissues were initially fixed followed by the classic TEM method. The authors found the topography of pure MCB cases to be without nodes. The cell membrane was smooth, with numerous pores and small ruffles that covered the entire cell. The ultrastructural appearance of the same cases was with a normal cell membrane containing abundant collagen fibers. They also had many small vesicles containing mucin as well as secretory droplets. In contrast the mixed MCB had a number of lymph nodes and their cell surface topography showed stronger changes such as microvilli, numerous blebs, ruffles and many long projections. Their ultrastructure showed very long microvilli with large cytoplasmic inclusions and extracellular mucin collections, electron-dense material vacuoles, and many important cytoplasmic organelles. An important fact is that mixed MCB also contains areas of infiltrating ductal carcinoma. These cells of the cytoplasmic organelles are clearly responsible for the synthesis, storage, and secretion of the characteristic mucin of this tumor type. Evidently, this abnormal mucin production and the abundance of secretory granules along with the long projections observed in the topographical structure might be responsible for transferring tumor cells to neighboring organs, thus being responsible for metastatic disease.

  3. SEASONAL DISTRIBUTION OF MALARIA VECTORS (DIPTERA: CULICIDAE IN RURAL LOCALITIES OF PORTO VELHO, RONDÔNIA, BRAZILIAN AMAZON

    Directory of Open Access Journals (Sweden)

    Luiz Herman Soares GIL

    2015-06-01

    Full Text Available We conducted a survey of the malaria vectors in an area where a power line had been constructed, between the municipalities of Porto Velho and Rio Branco, in the states of Rondônia and Acre, respectively. The present paper relates to the results of the survey of Anopheles fauna conducted in the state of Rondônia. Mosquito field collections were performed in six villages along the federal highway BR 364 in the municipality of Porto Velho, namely Porto Velho, Jaci Paraná, Mutum Paraná, Vila Abunã, Vista Alegre do Abunã, and Extrema. Mosquito captures were performed at three distinct sites in each locality during the months of February, July, and October 2011 using a protected human-landing catch method; outdoor and indoor captures were conducted simultaneously at each site for six hours. In the six sampled areas, we captured 2,185 mosquitoes belonging to seven Anopheles species. Of these specimens, 95.1% consisted of Anopheles darlingi, 1.8% An. triannulatus l.s., 1.7% An. deaneorum, 0.8% An. konderi l.s., 0.4 An. braziliensis, 0.1% An. albitarsis l.s., and 0.1% An. benarrochi. An. darlingi was the only species found in all localities; the remaining species occurred in sites with specific characteristics.

  4. High-spatial-resolution localization algorithm based on cascade deconvolution in a distributed Sagnac interferometer invasion monitoring system.

    Science.gov (United States)

    Pi, Shaohua; Wang, Bingjie; Zhao, Jiang; Sun, Qi

    2016-10-10

    In the Sagnac fiber optic interferometer system, the phase difference signal can be illustrated as a convolution of the waveform of the invasion with its occurring-position-associated transfer function h(t); deconvolution is introduced to improve the spatial resolution of the localization. In general, to get a 26 m spatial resolution at a sampling rate of 4×106  s-1, the algorithm should mainly go through three steps after the preprocessing operations. First, the decimated phase difference signal is transformed from the time domain into the real cepstrum domain, where a probable region of invasion distance can be ascertained. Second, a narrower region of invasion distance is acquired by coarsely assuming and sweeping a transfer function h(t) within the probable region and examining where the restored invasion waveform x(t) gets its minimum standard deviation. Third, fine sweeping the narrow region point by point with the same criteria is used to get the final localization. Also, the original waveform of invasion can be restored for the first time as a by-product, which provides more accurate and pure characteristics for further processing, such as subsequent pattern recognition.

  5. Uniform spatial distribution of collagen fibril radii within tendon implies local activation of pC-collagen at individual fibrils

    Science.gov (United States)

    Rutenberg, Andrew D.; Brown, Aidan I.; Kreplak, Laurent

    2016-08-01

    Collagen fibril cross-sectional radii show no systematic variation between the interior and the periphery of fibril bundles, indicating an effectively constant rate of collagen incorporation into fibrils throughout the bundle. Such spatially homogeneous incorporation constrains the extracellular diffusion of collagen precursors from sources at the bundle boundary to sinks at the growing fibrils. With a coarse-grained diffusion equation we determine stringent bounds, using parameters extracted from published experimental measurements of tendon development. From the lack of new fibril formation after birth, we further require that the concentration of diffusing precursors stays below the critical concentration for fibril nucleation. We find that the combination of the diffusive bound, which requires larger concentrations to ensure homogeneous fibril radii, and lack of nucleation, which requires lower concentrations, is only marginally consistent with fully processed collagen using conservative bounds. More realistic bounds may leave no consistent concentrations. Therefore, we propose that unprocessed pC-collagen diffuses from the bundle periphery followed by local C-proteinase activity and subsequent collagen incorporation at each fibril. We suggest that C-proteinase is localized within bundles, at fibril surfaces, during radial fibrillar growth. The much greater critical concentration of pC-collagen, as compared to fully processed collagen, then provides broad consistency between homogeneous fibril radii and the lack of fibril nucleation during fibril growth.

  6. Intracellular ice and cell survival in cryo-exposed embryonic axes of recalcitrant seeds of Acer saccharinum: an ultrastructural study of factors affecting cell and ice structures.

    Science.gov (United States)

    Wesley-Smith, James; Berjak, Patricia; Pammenter, N W; Walters, Christina

    2014-03-01

    Cryopreservation is the only long-term conservation strategy available for germplasm of recalcitrant-seeded species. Efforts to cryopreserve this form of germplasm are hampered by potentially lethal intracellular freezing events; thus, it is important to understand the relationships among cryo-exposure techniques, water content, structure and survival. Undried embryonic axes of Acer saccharinum and those rapidly dried to two different water contents were cooled at three rates and re-warmed at two rates. Ultrastructural observations were carried out on radicle and shoot tips prepared by freeze-fracture and freeze-substitution to assess immediate (i.e. pre-thaw) responses to cooling treatments. Survival of axes was assessed in vitro. Intracellular ice formation was not necessarily lethal. Embryo cells survived when crystal diameter was between 0·2 and 0·4 µm and fewer than 20 crystals were distributed per μm(2) in the cytoplasm. Ice was not uniformly distributed within the cells. In fully hydrated axes cooled at an intermediate rate, the interiors of many organelles were apparently ice-free; this may have prevented the disruption of vital intracellular machinery. Intracytoplasmic ice formation did not apparently impact the integrity of the plasmalemma. The maximum number of ice crystals was far greater in shoot apices, which were more sensitive than radicles to cryo-exposure. The findings challenge the accepted paradigm that intracellular ice formation is always lethal, as the results show that cells can survive intracellular ice if crystals are small and localized in the cytoplasm. Further understanding of the interactions among water content, cooling rate, cell structure and ice structure is required to optimize cryopreservation treatments without undue reliance on empirical approaches.

  7. Hillslope characterization: Identifying key controls on local-scale plant communities' distribution using remote sensing and subsurface data fusion.

    Science.gov (United States)

    Falco, N.; Wainwright, H. M.; Dafflon, B.; Leger, E.; Peterson, J.; Steltzer, H.; Wilmer, C.; Williams, K. H.; Hubbard, S. S.

    2017-12-01

    Mountainous watershed systems are characterized by extreme heterogeneity in hydrological and pedological properties that influence biotic activities, plant communities and their dynamics. To gain predictive understanding of how ecosystem and watershed system evolve under climate change, it is critical to capture such heterogeneity and to quantify the effect of key environmental variables such as topography, and soil properties. In this study, we exploit advanced geophysical and remote sensing techniques - coupled with machine learning - to better characterize and quantify the interactions between plant communities' distribution and subsurface properties. First, we have developed a remote sensing data fusion framework based on the random forest (RF) classification algorithm to estimate the spatial distribution of plant communities. The framework allows the integration of both plant spectral and structural information, which are derived from multispectral satellite images and airborne LiDAR data. We then use the RF method to evaluate the estimated plant community map, exploiting the subsurface properties (such as bedrock depth, soil moisture and other properties) and geomorphological parameters (such as slope, curvature) as predictors. Datasets include high-resolution geophysical data (electrical resistivity tomography) and LiDAR digital elevation maps. We demonstrate our approach on a mountain hillslope and meadow within the East River watershed in Colorado, which is considered to be a representative headwater catchment in the Upper Colorado Basin. The obtained results show the existence of co-evolution between above and below-ground processes; in particular, dominant shrub communities in wet and flat areas. We show that successful integration of remote sensing data with geophysical measurements allows identifying and quantifying the key environmental controls on plant communities' distribution, and provides insights into their potential changes in the future

  8. Inverter sizing of grid-connected photovoltaic systems in the light of local solar resource distribution characteristics and temperature

    Energy Technology Data Exchange (ETDEWEB)

    Burger, Bruno [Fraunhofer-Institute for Solar Energy Systems ISE, Department of Electrical Energy Systems, Heidenhofstr. 2, 79110 Freiburg (Germany); Ruether, Ricardo [LABSOLAR-Laboratorio de Energia Solar, LabEEE-Laboratorio de Eficiencia Energetica em Edificacoes, Universidade Federal de Santa Catarina/UFSC, Caixa Postal 476, Florianopolis-SC 88040-900 (Brazil)

    2006-01-15

    Inverter sizing strategies for grid-connected photovoltaic (PV) systems often do not take into account site-dependent peculiarities of ambient temperature, inverter operating temperature and solar irradiation distribution characteristics. The operating temperature affects PV modules and inverters in different ways and PV systems will hardly ever have a DC output equal to or above their STC-rated nominal power. Inverters are usually sized with a nominal AC output power some 30% (sometimes even more) below the PV array nominal power. In this paper, we show that this practice might lead to considerable energy losses, especially in the case of PV technologies with high temperature coefficients of power operating at sites with cold climates and of PV technologies with low temperature coefficients of power operating at sites with warm climates and an energy distribution of sunlight shifted to higher irradiation levels. In energy markets where PV kWh are paid premium tariffs, like in Germany, energy yield optimization might result in a favorable payback of the extra capital invested in a larger inverter. This paper discusses how the time resolution of solar radiation data influences the correct sizing of PV plants. We demonstrate that using instant (10s) irradiation values instead of average hourly irradiation values leads to considerable differences in optimum inverter sizing. When calculating inverter yearly efficiency values using both, hourly averages and 1-min averages, we can show that with increased time resolution of solar irradiation data there are higher calculated losses due to inverter undersizing. This reveals that hourly averages hide important irradiation peaks that need to be considered. We performed these calculations for data sets from pyranometer readings from Freiburg (48{sup o}N, Germany) and Florianopolis (27{sup o}S, Brazil) to further show the peculiarities of the site-dependent distribution of irradiation levels and its effects on inverter sizing

  9. Derivation of the probability distribution function for the local density of states of a disordered quantum wire via the replica trick and supersymmetry

    International Nuclear Information System (INIS)

    Bunder, J.E.J.E.; McKenzie, R.H.Ross H.

    2001-01-01

    We consider the statistical properties of the local density of states of a one-dimensional Dirac equation in the presence of various types of disorder with Gaussian white-noise distribution. It is shown how either the replica trick or supersymmetry can be used to calculate exactly all the moments of the local density of states. Careful attention is paid to how the results change if the local density of states is averaged over atomic length scales. For both the replica trick and supersymmetry the problem is reduced to finding the ground state of a zero-dimensional Hamiltonian which is written solely in terms of a pair of coupled 'spins' which are elements of u(1,1). This ground state is explicitly found for the particular case of the Dirac equation corresponding to an infinite metallic quantum wire with a single conduction channel. The calculated moments of the local density of states agree with those found previously by Al'tshuler and Prigodin [Sov. Phys. JETP 68 (1989) 198] using a technique based on recursion relations for Feynman diagrams

  10. [Spermatogonia types in tepezcuintle (Cuniculus paca). Ultrastructural study].

    Science.gov (United States)

    Ureña, F; Bolaños, R; Rojas, N; Suárez, R; Quesada, R

    1988-11-01

    Ultrastructural studies of different types of spermatogonia by thin section techniques and transmission electron microscopy showed that Cuniculus paca has two types of Type A spermatogonia (A-O and A-1). Samples were taken at different stages of the cycle in the seminiferous tubule epithelium presented a similar pattern as those of other rodents. Type B spermatogonia are similar to those of the rat, the difference being that the heterochromatic zones are larger and more numerous. Both characteristics differentiate them from preleptotenic spermatocytes.

  11. Simultaneous detection of multiple targets for ultrastructural immunocytochemistry

    Czech Academy of Sciences Publication Activity Database

    Philimonenko, Vlada; Filimonenko, Anatolij; Šloufová, I.; Hrubý, Martin; Novotný, F.; Halbhuber, Z.; Krivjanská, M.; Nebesářová, Jana; Šlouf, Miroslav; Hozák, Pavel

    2014-01-01

    Roč. 141, č. 3 (2014), s. 229-239 ISSN 0948-6143 R&D Projects: GA AV ČR KAN200520704; GA TA ČR TE01020118; GA ČR GAP305/11/2232; GA MŠk LD12063 Grant - others:Human Frontier Science Program(FR) RGP0017/2013 Institutional research plan: CEZ:AV0Z50520514 Institutional support: RVO:61389013 ; RVO:60077344 ; RVO:68378050 Keywords : Immunolabeling * Metal nanoparticles * Electron microscopy * Cell nucleus * Ultrastructure * Phosphatidylinositol-4,5-Bisphosphate (PIP2) Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.927, year: 2013

  12. Pathology of mitochondria in MELAS syndrome: an ultrastructural study.

    Science.gov (United States)

    Felczak, Paulina; Lewandowska, Eliza; Stępniak, Iwona; Ołdak, Monika; Pollak, Agnieszka; Lechowicz, Urszula; Pasennik, Elżbieta; Stępień, Tomasz; Wierzba-Bobrowicz, Teresa

    Ultrastructural changes in skeletal muscle biopsy in a 24-year-old female patient with clinically suspected mitochondrial encephalomyopathy lactic acidosis and stroke-like episodes (MELAS) syndrome are presented. We observed proliferation and/or pleomorphism of mitochondria in skeletal muscle and smooth muscle cells of arterioles, as well as in pericytes of capillaries. Paracrystalline inclusions were found only in damaged mitochondria of skeletal muscle. Genetic testing revealed a point mutation in A3243G tRNALeu(UUR) typical for MELAS syndrome. We conclude that differentiated pathological changes of mitochondria in the studied types of cells may be associated with the different energy requirements of these cells.

  13. The ultrastructural basis of steroid production in the Y-organ and the mandibular organ of the crabs Hemigrapsus nudus (Dana) and Carcinus maenas L.

    Science.gov (United States)

    Buchholz, C; Adelung, D

    1980-01-01

    The ultrastructure of the steroid producing Y-organ and the mandibular organ of the crustaceans Hemigrapsus nudus and Carcinus maenas has been studied with reference to the well investigated steroid secreting cells (SSC) of mammals. In accordance with the most important characteristic of mammalian SSC, abundant SER could be shown in the Y-organ, where it is unevenly distributed. The amount of SER seems to vary in correlation with the secretion of moulting hormone during the moult cycle. Most Y-organ cells contain a great number of mitochondria of the tubular type, another important characteristic of mammalian SSC. The ultrastructure of the mandibular organ of C. maenas differs considerably from that of the Y-organ. Some SER was found, mitochondria of unusual shape and size were conspicuous. No definite conclusion as to the function of the mandibular organ is yet to be drawn.

  14. Loveridge’s Angolan geckos, Afroedura karroica bogerti and Pachydactylus scutatus angolensis (Sauria, Gekkonidae: new distribution records, comments on type localities and taxonomic status

    Directory of Open Access Journals (Sweden)

    William R. Branch

    2017-03-01

    Full Text Available In 1944 Loveridge described two new geckos from Angola Afroedura karroica bogerti and Pachydactylus scutatus angolensis. The descriptions of both species have vague and confusing type localities and refinements are suggested based on early expedition reports historical accounts from the region and a review of cartographic material. Numerous new distribution records are reported for both species from expeditions undertaken from 1956–2016 by the authors or their colleagues. The taxonomic status of both species has changed but new material from diverse habitats altitudes and geological substrates indicates that further taxonomic adjustments are likely in order to reflect additional cryptic diversity.

  15. Re-distribution of brachytherapy dose using a differential dose prescription adapted to risk of local failure in low-risk prostate cancer patients

    DEFF Research Database (Denmark)

    Rylander, Susanne; Polders, Daniel; Steggerda, Marcel J

    2015-01-01

    BACKGROUND AND PURPOSE: We investigated the application of a differential target- and dose prescription concept for low-dose-rate prostate brachytherapy (LDR-BT), involving a re-distribution of dose according to risk of local failure and treatment-related morbidity. MATERIAL AND METHODS: Our study......- and dose prescription concept of prescribing a lower dose to the whole gland and an escalated dose to the GTV using LDR-BT seed planning was technically feasible and resulted in a significant dose-reduction to urethra and bladder neck....

  16. Local controls on sediment accumulation and distribution in a fjord in the West Antarctic Peninsula: implications for palaeoenvironmental interpretations

    Directory of Open Access Journals (Sweden)

    Yuribia P. Munoz

    2016-08-01

    Full Text Available We analyse surface sediment and its distribution in Flandres Bay, West Antarctic Peninsula, in order to understand modern day sediment dispersal patterns in a fjord with retreating, tidewater glaciers. The surface sediment descriptions of 41 cores are included in this study. The sediment facies described include muddy diatomaceous ooze, diatomaceous mud, pebbly mud, sandy mud and mud, with scattered pebbles present in most samples. In contrast to a traditional conceptual model of glacial sediment distribution in fjords, grain size in Flandres Bay generally coarsens from the inner to outer bay. The smallest grain size sediments were found in the bay head and are interpreted as fine-grained deposits resulting from meltwater plumes and sediment gravity flows occurring close to the glacier front. The middle of the bay is characterized by a high silt percentage, which correlates to diatom-rich sediments. Sediments in the outer bay have a high component of coarse material, which is interpreted as being the result of winnowing from currents moving from the Bellingshausen Sea into the Gerlache Strait. Palaeoenvironmental reconstructions of glacial environments often use grain size as an indicator of proximity to the ice margin. After a detailed analysis of a large number of cores collected in the study area, our findings highlight the variability in sedimentation patterns within a fjord and provide a valuable evidence of the complexity that may occur in the sedimentary record.

  17. Processes affecting altitudinal distribution of invasive Ageratina adenophora in western Himalaya: The role of local adaptation and the importance of different life-cycle stages.

    Science.gov (United States)

    Datta, Arunava; Kühn, Ingolf; Ahmad, Mustaqeem; Michalski, Stefan; Auge, Harald

    2017-01-01

    The spread of invasive plants along elevational gradients is considered a threat to fragile mountain ecosystems, but it can also provide the opportunity to better understand some of the basic processes driving the success of invasive species. Ageratina adenophora (Asteraceae) is an invasive plant of global importance and has a broad distribution along elevational gradients in the Western Himalayas. Our study aimed at understanding the role of evolutionary processes (e.g. local adaptation and clinal differentiation) and different life history stages in shaping the distribution pattern of the invasive plant along an elevational gradient in the Western Himalaya. We carried out extensive distributional surveys, established a reciprocal transplant experiment with common gardens at three elevational levels, and measured a suite of traits related to germination, growth, reproduction and phenology. Our results showed a lack of local adaptation, and we did not find any evidence for clinal differentiation in any measured trait except a rather weak signal for plant height. We found that seed germination was the crucial life-cycle transition in determining the lower range limit while winter mortality of plants shaped the upper range limit in our study area, thus explaining the hump shaped distribution pattern. Differences in trait values between gardens for most traits indicated a high degree of phenotypic plasticity. Possible causes such as apomixis, seed dispersal among sites, and pre-adaptation might have confounded evolutionary processes to act upon. Our results suggest that the success and spread of Ageratina adenophora are dependent on different life history stages at different elevations that are controlled by abiotic conditions.

  18. Simulating the effects of climate change on the distribution of an invasive plant, using a high resolution, local scale, mechanistic approach: challenges and insights.

    Science.gov (United States)

    Fennell, Mark; Murphy, James E; Gallagher, Tommy; Osborne, Bruce

    2013-04-01

    The growing economic and ecological damage associated with biological invasions, which will likely be exacerbated by climate change, necessitates improved projections of invasive spread. Generally, potential changes in species distribution are investigated using climate envelope models; however, the reliability of such models has been questioned and they are not suitable for use at local scales. At this scale, mechanistic models are more appropriate. This paper discusses some key requirements for mechanistic models and utilises a newly developed model (PSS[gt]) that incorporates the influence of habitat type and related features (e.g., roads and rivers), as well as demographic processes and propagule dispersal dynamics, to model climate induced changes in the distribution of an invasive plant (Gunnera tinctoria) at a local scale. A new methodology is introduced, dynamic baseline benchmarking, which distinguishes climate-induced alterations in species distributions from other potential drivers of change. Using this approach, it was concluded that climate change, based on IPCC and C4i projections, has the potential to increase the spread-rate and intensity of G. tinctoria invasions. Increases in the number of individuals were primarily due to intensification of invasion in areas already invaded or in areas projected to be invaded in the dynamic baseline scenario. Temperature had the largest influence on changes in plant distributions. Water availability also had a large influence and introduced the most uncertainty in the projections. Additionally, due to the difficulties of parameterising models such as this, the process has been streamlined by utilising methods for estimating unknown variables and selecting only essential parameters. © 2012 Blackwell Publishing Ltd.

  19. Determination of local-area distribution and relocation of radioactive cesium in trees from Fukushima Daiichi Nuclear Power Plant by autoradiography analysis

    International Nuclear Information System (INIS)

    Sakamoto, Fuminori; Ohnuki, Toshihiko; Kozai, Naofumi; Yamasaki, Shinya; Yoshida, Zenko; Nanba, Kenji

    2013-01-01

    The local area distribution and relocation of radioactive cesium deposited in trees after the 2011 tsunami-related accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP) have been studied by measuring the spatial distribution of cesium on/in trees by autoradiography analysis. Samples of trees were collected from places located between 4 and 55 km from FDNPP approximately 2, 8, 20, and 22 months after the accident. The autoradiography analyses of Cryptomeria japonica, Torreya nucifera, and Thujopsis dolabrata var. hondae samples collected approximately 2 and 8 months after the accident showed that radioactive Cs was mainly distributed as spots on the branches and leaves of the trees emerged before the accident, and was detected in negligible amounts in new branch and leaves that emerged after the accident. On the contrary, radioactive Cs was detected at the outermost tip of the branches in the trees collected 20 months after the accident. Morus alba samples collected 22 months after the accident contained radioactive Cs inside and outside their stems, even though no radioactive Cs was detected in their roots, strongly suggesting that a certain amount of radioactive Cs was translocated from the outside to the inside of stems. These results indicate that the distribution of radioactive Cs deposited on/in the trees gradually changes with time (scale: year). (author)

  20. Tracer test modeling for characterizing heterogeneity and local scale residence time distribution in an artificial recharge site.

    Science.gov (United States)

    Valhondo, Cristina; Martinez-Landa, Lurdes; Carrera, Jesús; Hidalgo, Juan J.; Ayora, Carlos

    2017-04-01

    Artificial recharge of aquifers (AR) is a standard technique to replenish and enhance groundwater resources, that have widely been used due to the increasing demand of quality water. AR through infiltration basins consists on infiltrate surface water, that might be affected in more or less degree by treatment plant effluents, runoff and others undesirables water sources, into an aquifer. The water quality enhances during the passage through the soil and organic matter, nutrients, organic contaminants, and bacteria are reduced mainly due to biodegradation and adsorption. Therefore, one of the goals of AR is to ensure a good quality status of the aquifer even if lesser quality water is used for recharge. Understand the behavior and transport of the potential contaminants is essential for an appropriate management of the artificial recharge system. The knowledge of the flux distribution around the recharge system and the relationship between the recharge system and the aquifer (area affected by the recharge, mixing ratios of recharged and native groundwater, travel times) is essential to achieve this goal. Evaluate the flux distribution is not always simple because the complexity and heterogeneity of natural systems. Indeed, it is not so much regulate by hydraulic conductivity of the different geological units as by their continuity and inter-connectivity particularly in the vertical direction. In summary for an appropriate management of an artificial recharge system it is needed to acknowledge the heterogeneity of the media. Aiming at characterizing the residence time distribution (RTDs) of a pilot artificial recharge system and the extent to which heterogeneity affects RTDs, we performed and evaluated a pulse injection tracer test. The artificial recharge system was simulated as a multilayer model which was used to evaluate the measured breakthrough curves at six monitoring points. Flow and transport parameters were calibrated under two hypotheses. The first

  1. Ultrastructural observations of chemical peeling for skin rejuvenation (ultrastructural changes of the skin due to chemical peeling).

    Science.gov (United States)

    Omi, Tokuya; Sato, Shigeru; Numano, Kayoko; Kawana, Seiji

    2010-02-01

    Chemical peeling of the skin is commonly used as a means to treat photoaging, but the mechanism underlying its efficacy has not yet been fully clarified. We recently conducted chemical peeling of the skin with glycolic acid and lactic acid and observed it at the ultrastructural level. No changes in the horny layer or the upper epidermal layer were observed but there was dissociation and vacuolation between the basal cells and increases in vimentin filaments within fibroblasts and endothelial cells were seen. These findings suggest that chemical peeling of the skin with this type of agent directly induces collagen formation within the dermis and thus directly stimulates remodeling of the dermis.

  2. Demonstration of thin film pair distribution function analysis (tfPDF for the study of local structure in amorphous and crystalline thin films

    Directory of Open Access Journals (Sweden)

    Kirsten M. Ø. Jensen

    2015-09-01

    Full Text Available By means of normal-incidence, high-flux and high-energy X-rays, total scattering data for pair distribution function (PDF analysis have been obtained from thin films (tf, suitable for local structure analysis. By using amorphous substrates as support for the films, the standard Rapid Acquisition PDF setup can be applied and the scattering signal from the film can be isolated from the total scattering data through subtraction of an independently measured background signal. No angular corrections to the data are needed, as would be the case for grazing incidence measurements. The `tfPDF' method is illustrated through studies of as-deposited (i.e. amorphous and crystalline FeSb3 films, where the local structure analysis gives insight into the stabilization of the metastable skutterudite FeSb3 phase. The films were prepared by depositing ultra-thin alternating layers of Fe and Sb, which interdiffuse and after annealing crystallize to form the FeSb3 structure. The tfPDF data show that the amorphous precursor phase consists of corner-sharing FeSb6 octahedra with motifs highly resembling the local structure in crystalline FeSb3. Analysis of the amorphous structure allows the prediction of whether the final crystalline product will form the FeSb3 phase with or without excess Sb present. The study thus illustrates how analysis of the local structure in amorphous precursor films can help to understand crystallization processes of metastable phases and opens for a range of new local structure studies of thin films.

  3. Ultrastructural and metabolic changes in osteoblasts exposed to uranyl nitrate

    International Nuclear Information System (INIS)

    Tasat, D.R.; Orona, N.S.; Mandalunis, P.M.; Cabrini, R.L.; Ubios, A.M.

    2007-01-01

    Exposure to uranium is an occupational hazard to workers who continually handle uranium and an environmental risk to the population at large. Since the cellular and molecular pathways of uranium toxicity in osteoblast cells are still unknown, the aim of the present work was to evaluate the adverse effects of uranyl nitrate (UN) on osteoblasts both in vivo and in vitro. Herein we studied the osteoblastic ultrastructural changes induced by UN in vivo and analyzed cell proliferation, generation of reactive oxygen species (ROS), apoptosis, and alkaline phosphatase (APh) activity in osteoblasts exposed to various UN concentrations (0.1, 1, 10, and 100 μM) in vitro. Cell proliferation was quantified by means of the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, ROS was determined using the nitro blue tetrazolium test, apoptosis was morphologically determined using Hoechst 3332 and APh activity was assayed spectrophotometrically. Electron microscopy revealed that the ultrastructure of active and inactive osteoblasts exposed to uranium presented cytoplasmic and nuclear alterations. In vitro, 1-100 μM UN failed to modify cell proliferation ratio and to induce apoptosis. ROS generation increased in a dose-dependent manner in all tested doses. APh activity was found to decrease in 1-100 μM UN-treated cells vs. controls. Our results show that UN modifies osteoblast cell metabolism by increasing ROS generation and reducing APh activity, suggesting that ROS may play a more complex role in cell physiology than simply causing oxidative damage. (orig.)

  4. Ultrastructural evaluation of gingival connective tissue in hereditary gingival fibromatosis.

    Science.gov (United States)

    Pêgo, Sabina Pena B; de Faria, Paulo Rogério; Santos, Luis Antônio N; Coletta, Ricardo D; de Aquino, Sibele Nascimento; Martelli-Júnior, Hercílio

    2016-07-01

    To describe the ultrastructural features of hereditary gingival fibromatosis (HGF) in affected family members and compare microscopic findings with normal gingival (NG) tissue. Gingival tissue samples from nine patients with HGF from five unrelated families were evaluated by transmission electron microscopy. Nine NG tissue samples were used for comparison. Areas containing collagen fibrils forming loops and folds were observed in both groups, whereas oxytalan fibers were frequently identified in the HGF group. The diameter of collagen fibrils and the interfibrillar space among them were more uniform in the NG group than in the HGF group. Fibroblasts were the most common cells found in both the HGF and NG groups and exhibited enlarged, rough endoplasmic reticulum, mitochondria with well-preserved crests, conspicuous nucleoli, and euchromatic chromatin. Other cells, such as mast cells, plasma cells, and macrophages, were also observed. HGF tissues had ultrastructural characteristics that were very similar to those of NG tissues. Oxytalan fibers were observed more frequently in the HGF samples than in the NG samples. Other studies of HGF in patients from different families should be performed to better understand the pathogenesis of this hereditary condition. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Collyricloides massanae (Digenea, Collyriclidae: spermatozoon ultrastructure and phylogenetic importance

    Directory of Open Access Journals (Sweden)

    Bakhoum Abdoulaye Jacque

    2014-01-01

    Full Text Available The spermatological characteristics of Collyricloides massanae (Digenea: Collyriclidae, a parasite of Apodemus sylvaticus caught in France, were studied by means of transmission electron microscopy. The mature sperm of C. massanae presents two axonemes of different lengths with the 9 + “1” pattern of the Trepaxonemata, two bundles of parallel cortical microtubules, external ornamentation of the plasma membrane, spine-like bodies, one mitochondrion, a nucleus and granules of glycogen. An analysis of spermatological organisation emphasised some differences between the mature spermatozoon of C. massanae and those reported in the Gorgoderoidea species studied to date, specially belonging to the families Dicrocoeliidae, Paragonimidae and Troglotrematidae. The ultrastructural criteria described in C. massanae such as the morphology of both anterior and posterior spermatozoon extremities, the association “external ornamentation + cortical microtubules”, the type 2 of external ornamentation and the spine-like bodies would allow us to bring closer the Collyriclidae to Microphalloidea. However, further ultrastructural and molecular studies are needed particularly in the unexplored taxa in order to fully resolve the phylogenetic position of the Collyriclidae.

  6. Ultrastructural investigation on radiation resistant microbial isolates of bacillus coagulans

    International Nuclear Information System (INIS)

    Tawfik, Z.S.

    1992-01-01

    Radiation resistant strains of bacillus coagulans were isolated from environmental atmospheric surrounding industrial cobalt-60 irradiator. D 1 0 value of the studied isolate was found to be 3.3 KGy. Ultrastructure studies were performed on control isolates as well as on isolates exposed to challenging doses of 12, 15 and 25 KGy. These dose values were delivered at two different dose rate values 40 Gy/min and 300 Gy/min. Ultrastructure studies showed small differences due to dose rate effect. These differences were not sufficient to cause lethality changes. It was demonstrated that the growing effect of dose value is concentrated on cellular material rather than on cellular membrane damages. The severeness of cell damage, due to received dose increase, was also demonstrated. Results suggest that repeated sub culturing may lead to repair of cell damage when it is subjected to sub sterilizing doses. This fact is of special interest when the sterilizing dose might be splitted in more than one fraction at different latent periods

  7. The Ultrastructural Effects of Sulfachloropyrazine on Toxoplasma Gondii Tachyzoites

    Directory of Open Access Journals (Sweden)

    YB Zeng

    2013-03-01

    Full Text Available Background: Toxoplasmosis is one of the most common parasitic infections of humans and other mammals. This study was aimed to understand the mechanism of action of veterinary medicine-sulfachlo­ropyrazine (SPZ, 99.97% against Toxoplasma gondii.Methods: T. gondii tachyzoites were soaked in PBS (as a control or SPZ (250 mg/mL for 2 h at 37 °C. After being processed, any ultrastructural changes of the tachyzoites that had occurred were observed by Scanning Electron Microscopy (SEM and Transmission Electron Microscopy (TEM.Results: The tachyzoites from control groups with a uniform size had a smooth surface and intact cell or nuclear membranes. In addition, an oval-shaped nucleus, conoids and micronemes were also observed. By contrast, many parasites from the SPZ-treated groups were detrimentally affected by the treatment. Some appeared to be of the vacuolization in their cytoplasm, with the substantial reduc­tion in the number of dense granules and the blur of some organelles.Conclusion: The morphology and ultrastructure of tachyzoites can be affected significantly by SPZ, which might kill the parasite by inhibiting its energy metabolism, inducing apoptosis and damaging its structure. The study provides an experimental basis for further study on the mechanism of SPZ against T. gondii.

  8. Ultrastructural, autoradiographic and electrophoretic examinations of Chara tomentosa spermiogenesis

    Directory of Open Access Journals (Sweden)

    Maria Kwiatkowska

    2014-01-01

    Full Text Available Ultrastructure of a spermatid nucleus changes many times during spermiogenesis. Condensed chromatin forms irregular clusters during phases I-II, a continuous ring adjacent to a nuclear envelope during phases III-V and a network occupying the whole nucleus during phase VI. In advanced spermiogenesis dense chromatin disappears and short randomly positioned fibrils arise, then long parallel ones are found (phase VIII which during phase IX form a lamellar structure. In mature spermatozoids (phase X chromatin becomes extremely condensed. 3H-arginine and 3H-lysine incorporation into spermatids during 2-min incubation is intensive during phases IN, decreases during phases VI, VII and becomes very low during phases VIII-IX. Capillary electrophoresis has shown that during Chara tomentosa spermiogenesis replacement of histones with basic proteins whose mobility is comparable to that of salmon protamines takes place. At the beginning of spermiogenesis core and linker histones are found in spermatids. During early spermiogenesis protamine-like proteins appear and their amount increases in late spermiogenesis when core histones are still present. In mature spermatozoids only protamine-like proteins represented by 3 fractions: 9.1 kDa, 9.6 kDa, 11.2 kDa are found. Disappearance of linker histones following their modification precedes disappearance of core histones. The results indicate that dynamic rearrangement of chromatin ultrastructure and aminoacid incorporation rate during spermiogenesis are reflected in basic nuclear protein changes.

  9. Giardia agilis: Ultrastructure of the Trophozoites in the Frog Intestine

    Directory of Open Access Journals (Sweden)

    Maria Inês L Sogayar

    1998-05-01

    Full Text Available Intestine samples of Bufo sp. tadpoles with parasitism confirmed for Giardia agilis were studied by transmission electron microscopy. The G. agilis trophozoites were long and thin. The plasma membrane was sometimes undulated and the cytoplasm, adjacent to the dorsal and ventral regions, showed numerous vacuoles. The two nuclei presented prominent nucleoli. The cytoplasm was electron-dense with free ribosomes, glycogen and rough endoplasmic reticulum-like structures. Polyhedral inclusions were observed in the cytoplasm and outside the protozoan; some of these inclusions exhibited membrane disruption. The flagella ultrastructure is typical, with the caudal pair accompanied by the funis. Next to the anterior pair, osmiophilic material was noticed. The ventro-lateral flange was short and thick, supported by the marginal plates that penetrated into its distal extremity; only its distal portion had adjacent osmiophilic filament. The G. agilis trophozoites showed the general subcellular feature of the genus. However, the ventro-lateral flange ultrastructure was an intermediate type between G. muris and G. duodenalis.

  10. Ultrastructural study of the chromatoid body in planarian regenerative cells

    Energy Technology Data Exchange (ETDEWEB)

    Hori, I. (Kanazawa Medical Univ., Ishikawa (Japan))

    1982-04-01

    The present paper deals with the ultrastructural changes of chromatoid bodies in planarian regenerative cells under normal and experimental conditions. A close relationship was usually observed between chromatoid bodies and pore regions of the nuclear envelope in these cells. The chromatoid bodies continued to decrease in size during cytodifferentiation of regenerative cells, though they did not disappear entirely throughout the regeneration processes. Cytochemistry and (/sup 3/H)uridine autoradiography have shown that the chromatoid body contains RNA. The typical morphological effect of actinomycin D became apparent in three organelles, i.e., nucleolus, polysome and chromatoid body. Ultrastructural changes in nucleoli were observed to occur after actinomycin treatment (20 ..mu..g/ml). The exposure to a higher dose of actinomycin (50 ..mu..g/ml) caused a decay of chromatoid bodies while nuclear envelopes retained numerous pores. Both the nucleoli and the chromatoid bodies disappeared in the sequential stages. Within the cytoplasm of such cells disintegration of a polysomal pattern was correlated with the disappearance of chromatoid bodies. The significance of the planarian chromatoid body is discussed in relation to differentiation of the regenerative cells.

  11. Ultrastructural study of tissues surrounding replanted teeth and dental implants.

    Science.gov (United States)

    Shioya, Kazuhiro; Sawada, Takashi; Miake, Yasuo; Inoue, Sadayuki; Yanagisawa, Takaaki

    2009-03-01

    The aim of this study was to describe the ultrastructure of the dentogingival border at replanted teeth and implants. Wistar rats (8 weeks old) were divided into groups for replantation and implantation experiments. In the former, the upper right first molars were extracted and then immediately replanted. In the latter, pure titanium implants were used. All tissues were fixed, demineralized and embedded in epoxy resin for ultrastructural observations. One week after replantation, the junctional epithelium was lost, and the oral sulcular epithelium covered the enamel surface. The amount of the epithelium increased in 2 weeks, and resembled the junctional epithelium, and the internal basal lamina and hemidesmosomes were formed in 4 weeks. One week after implantation, peri-implant epithelium was formed, and in 2 and 4 weeks, this epithelium with aggregated connective tissue cells were observed. In 8 weeks, the peri-implant epithelium receded, and aligned special cells with surrounding elongated fibroblasts and bundles of collagen fibers appeared to seal the implant interface. In replantation of the tooth, the internal basal lamina remained at the surface of the enamel of the replanted tooth, which is likely to be related to regeneration of the junctional epithelium and the attachment apparatus at the epithelium-tooth interface. Following implantation, a layer of cells with characteristics of connective tissue cells, but no junctional epithelium and attachment apparatus, was formed to seal the site of the implant.

  12. Dietary adaptions in the ultrastructure of dinosaur dentine.

    Science.gov (United States)

    Brink, Kirstin S; Chen, Yu-Cheng; Wu, Ya-Na; Liu, Wei-Min; Shieh, Dar-Bin; Huang, Timothy D; Sun, Chi-Kuang; Reisz, Robert R

    2016-12-01

    Teeth are key to understanding the feeding ecology of both extant and extinct vertebrates. Recent studies have highlighted the previously unrecognized complexity of dinosaur dentitions and how specific tooth tissues and tooth shapes differ between taxa with different diets. However, it is unknown how the ultrastructure of these tooth tissues contributes to the differences in feeding style between taxa. In this study, we use third harmonic generation microscopy and scanning electron microscopy to examine the ultrastructure of the dentine in herbivorous and carnivorous dinosaurs to understand how the structure of this tissue contributes to the overall utility of the tooth. Morphometric analyses of dentinal tubule diameter, density and branching rates reveal a strong signal for dietary preferences, with herbivorous saurischian and ornithischian dinosaurs consistently having higher dentinal tubule density than their carnivorous relatives. We hypothesize that this relates to the hardness of the dentine, where herbivorous taxa have dentine that is more resistant to breakage and wear at the dentine-enamel junction than carnivorous taxa. This study advocates the detailed study of dentine and the use of advanced microscopy techniques to understand the evolution of dentition and feeding ecology in extinct vertebrates. © 2016 The Author(s).

  13. Partial distribution strategy of local conflict in evidence theory%证据推理中局部冲突部分分配策略

    Institute of Scientific and Technical Information of China (English)

    曹洁; 孟兴

    2012-01-01

    为了解决证据理论中冲突证据合成问题,提出了一种局部冲突部分分配策略.该策略假设证据具有一致可信度,设定一个阈值,将大于该阈值的局部冲突按比例分配给产生该冲突的焦元,并用标准合成规则对证据进行融合,使合成的结果更加可靠.仿真结果表明该策略能有效解决冲突证据合成问题.%In order to solve the problem of conflict evidence combination in standard evidence theory, this paper proposed a kind of partial distribution strategy of local conflict. Assuming that the evidences had consistent reliability, the method proportionally distributed the local conflicts which was greater than threshold to those focus elements which contributed to the conflict. Then, it used the standard combination rule to achieve evidence fusion and obtained more reliable results. The simulation results demonstrate that the proposed method can effectively solve the problem to conflict evidence combination.

  14. The influence of local glucose oxidase activity on the potential/current distribution on stainless steel: A study by the wire beam electrode method

    Energy Technology Data Exchange (ETDEWEB)

    Wang Wei [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, College of Chemistry and Chemical Engineering, Qingdao, 266100 (China)], E-mail: wwei@ouc.edu.cn; Zhang Xia [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, College of Chemistry and Chemical Engineering, Qingdao, 266100 (China); Wang Jia [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, College of Chemistry and Chemical Engineering, Qingdao, 266100 (China); State Key Laboratory for Corrosion and Protection, Shenyang, 110016 (China)

    2009-09-30

    The wire beam electrode (WBE) method was first used to study the activity of local glucose oxidase (GOD) on stainless steel surface in seawater. Glucose oxidase was immobilized in calcium alginate gel capsules, which were embedded in a layer of artificial biofilm (calcium alginate gel) on the WBE surface. The potential/current distributions on the WBE surface were mapped using a newly developed device for the WBE method in our lab. The results demonstrated that the catalysis of H{sub 2}O{sub 2} formation by GOD can produce local noble potential peaks and cathodic current zones on the stainless steel surface. An interesting fluctuant current distribution around cathodic zones was observed the first time. The potential and current maps showed that the enzyme heterogeneity of the artificial biofilm caused a corresponding electrochemical heterogeneity at the biofilm/metal interface. The application of the WBE method to ennoblement study enables us to observe the heterogeneous electrochemistry at biofilm/stainless steel interface directly, providing us with a powerful tool to investigate other biofilm-related processes such as microbially influenced corrosion (MIC)

  15. The influence of local glucose oxidase activity on the potential/current distribution on stainless steel: A study by the wire beam electrode method

    International Nuclear Information System (INIS)

    Wang Wei; Zhang Xia; Wang Jia

    2009-01-01

    The wire beam electrode (WBE) method was first used to study the activity of local glucose oxidase (GOD) on stainless steel surface in seawater. Glucose oxidase was immobilized in calcium alginate gel capsules, which were embedded in a layer of artificial biofilm (calcium alginate gel) on the WBE surface. The potential/current distributions on the WBE surface were mapped using a newly developed device for the WBE method in our lab. The results demonstrated that the catalysis of H 2 O 2 formation by GOD can produce local noble potential peaks and cathodic current zones on the stainless steel surface. An interesting fluctuant current distribution around cathodic zones was observed the first time. The potential and current maps showed that the enzyme heterogeneity of the artificial biofilm caused a corresponding electrochemical heterogeneity at the biofilm/metal interface. The application of the WBE method to ennoblement study enables us to observe the heterogeneous electrochemistry at biofilm/stainless steel interface directly, providing us with a powerful tool to investigate other biofilm-related processes such as microbially influenced corrosion (MIC).

  16. Value of the quantity and distribution of subarachnoid haemorrhage on CT in the localization of ruptured cerebral aneurysm

    International Nuclear Information System (INIS)

    Karttunen, A.I.; Jartti, P.H.; Haapea, M.; Ukkola, V.A.; Sajanti, J.

    2003-01-01

    Computed tomography (CT) is the 'gold standard' for detecting subarachnoid haemorrhage (SAH) and digital subtraction angiography (DSA) for visualising the vascular pathology. We studied retrospectively 180 patients with subarachnoid haemorrhage (SAH) who underwent first non-enhanced computed tomography (CT), then digital subtraction angiography (DSA) and finally operative aneurysm clipping. Our aim was to assess if the location of the ruptured aneurysm could be predicted on the basis of the quantity and distribution of haemorrhage on the initial CT scan. 180 patients with SAH were retrospectively studied. All the CT and DSA examinations were performed at the same hospital. CT was performed within 24 hours after the initial haemorrhage. DSA was performed alter the CT, within 48 hours after the initial haemorrhage. Two neuroradiologists, blind to the DSA results, analysed and scored independently the quantity and distribution of the haemorrhage and predicted the site of the ruptured aneurysm on the basis of the non-enhanced CT. DSA provided the location of the ruptured aneurysm. All the patients were operated upon, and the location of the ruptured aneurysm was determined. The overall reliability value (r,-value) between the two neuroradiologists for locating all ruptured aneurysms was 0.780. The corresponding value for the right MCA was 0.911, that for the left MCA 0.877 and that for the AcoA 0.736. Not all of the rc-values were calculated, either because the location of the rupture was constant or because the number of ruptures in the vessel was too small. Subarachnoid haemorrhage with a parenchymal hematoma is an excellent predictor of the site of the ruptured aneurysm with a statistical significance of p = 0.003. The quantity and pattern of the blood clot an CT within the day of onset of SAH is a reliable and quick cool for locating a ruptured MCA or AcoA aneurysm. It is not, however, reliable for locating other ruptured aneurysms. Subarachnoid haemorrhage with a

  17. Vertical distribution of 90Sr and 137 Cs in uncultivated soil in three localities of central Bohemia

    International Nuclear Information System (INIS)

    Schlesingerova, E.; Hejnova, P.; Tecl, J.; Mirchi, R.; Setrna, L.; Macurova, L.

    2005-01-01

    The purpose of this work was study the vertical distribution of 90 Sr and 137 Cs in uncultivated soils. The radionuclide contents in different soil layers and the cumulative deposition of radionuclides at the study sites were to be established with a view to possible identification of their sources. The present paper investigated the vertical distribution of 90 Sr and 137 Cs in uncultivated soil samples in central Bohemia and inventory of these radionuclides at representative sampling sites. These data provide the information about the availability, movement and environmental behaviour of these important radionuclides in the study region. The cumulative deposition of 90 Sr at sites 1, 2 and 3 were found of 700, 1390 and 970 Bq/m 2 , respectively, The cumulative deposition of 137 Cs at sites 1, 2 and 3 were found of 260, 510 and 10000 Bq/m 2 , respectively. The obtained values of 9S r are about 47% lower than the value of UNSCEAR inventories, but our average value of 137 Cs (3590 Bq/m 2 ) agree with the cumulative deposition of 137 Cs from the atmospheric nuclear tests in northern 40 grad - 50 grad temperate zone according UNSCEAR inventories. The radioactive decay should have reduced the reported 90 Sr and 137 Cs inventories in the northern hemisphere to 2190 Bq/m 2 and 3580 Bq/m 2 , respectively. The concentration of 90 Sr and 137 Cs increased proportionally to the SOM content in soil, but the difference of the degree of correlation among 90 Sr and 137 CS could be explained by the fact that SOM held 137 Cs more strongly than 90 Sr. 137 Cs showed very low mobility in soil profiles in undisturbed soils, therefore, it was concentrated in the upper 10 cm of the soils. Although the concentration of 90 Sr increased with organic content through an anion exchange reaction, which is enhanced by SOM keeping high cationic exchange capacity, the retention of Sr was relatively weak in contrast to Cs. It is related with high mobility of Sr that is a member of group II in the

  18. Cellular and ultrastructural characterization of the grey-morph phenotype in southern right whales (Eubalaena australis).

    Science.gov (United States)

    Eroh, Guy D; Clayton, Fred C; Florell, Scott R; Cassidy, Pamela B; Chirife, Andrea; Marón, Carina F; Valenzuela, Luciano O; Campbell, Michael S; Seger, Jon; Rowntree, Victoria J; Leachman, Sancy A

    2017-01-01

    Southern right whales (SRWs, Eubalena australis) are polymorphic for an X-linked pigmentation pattern known as grey morphism. Most SRWs have completely black skin with white patches on their bellies and occasionally on their backs; these patches remain white as the whale ages. Grey morphs (previously referred to as partial albinos) appear mostly white at birth, with a splattering of rounded black marks; but as the whales age, the white skin gradually changes to a brownish grey color. The cellular and developmental bases of grey morphism are not understood. Here we describe cellular and ultrastructural features of grey-morph skin in relation to that of normal, wild-type skin. Melanocytes were identified histologically and counted, and melanosomes were measured using transmission electron microscopy. Grey-morph skin had fewer melanocytes when compared to wild-type skin, suggesting reduced melanocyte survival, migration, or proliferation in these whales. Grey-morph melanocytes had smaller melanosomes relative to wild-type skin, normal transport of melanosomes to surrounding keratinocytes, and normal localization of melanin granules above the keratinocyte nuclei. These findings indicate that SRW grey-morph pigmentation patterns are caused by reduced numbers of melanocytes in the skin, as well as by reduced amounts of melanin production and/or reduced sizes of mature melanosomes. Grey morphism is distinct from piebaldism and albinism found in other species, which are genetic pigmentation conditions resulting from the local absence of melanocytes, or the inability to synthesize melanin, respectively.

  19. Docosahexaenoic Acid Conjugation Enhances Distribution and Safety of siRNA upon Local Administration in Mouse Brain

    Directory of Open Access Journals (Sweden)

    Mehran Nikan

    2016-01-01

    Full Text Available The use of siRNA-based therapies for the treatment of neurodegenerative disease requires efficient, nontoxic distribution to the affected brain parenchyma, notably the striatum and cortex. Here, we describe the synthesis and activity of a fully chemically modified siRNA that is directly conjugated to docosahexaenoic acid (DHA, the most abundant polyunsaturated fatty acid in the mammalian brain. DHA conjugation enables enhanced siRNA retention throughout both the ipsilateral striatum and cortex following a single, intrastriatal injection (ranging from 6–60 μg. Within these tissues, DHA conjugation promotes internalization by both neurons and astrocytes. We demonstrate efficient and specific silencing of Huntingtin mRNA expression in both the ipsilateral striatum (up to 73% and cortex (up to 51% after 1 week. Moreover, following a bilateral intrastriatal injection (60 μg, we achieve up to 80% silencing of a secondary target, Cyclophilin B, at both the mRNA and protein level. Importantly, DHA-hsiRNAs do not induce neural cell death or measurable innate immune activation following administration of concentrations over 20 times above the efficacious dose. Thus, DHA conjugation is a novel strategy for improving siRNA activity in mouse brain, with potential to act as a new therapeutic platform for the treatment of neurodegenerative disorders.

  20. Damage localization using a power-efficient distributed on-board signal processing algorithm in a wireless sensor network

    International Nuclear Information System (INIS)

    Liu, Lei; Liu, Shuntao; Yuan, Fuh-Gwo

    2012-01-01

    A distributed on-board algorithm that is embedded and executed within a group of wireless sensors to locate structural damages in isotropic plates is presented. The algorithm is based on an energy-decay model of Lamb waves and singular value decomposition (SVD) to determine damage locations. A sensor group consists of a small number of sensors, each of which independently collects wave signals and evaluates wave energy upon an external triggering signal sent from a base station. The energy values, usually a few bytes in length, are then sent to the base station to determine the presence and location of damages. In comparison with traditional centralized approaches in which whole datasets are required to be transmitted, the proposed algorithm yields much less wireless communication traffic, yet with a modest amount of computation required within sensors. Experiments have shown that the algorithm is robust to locate damage for isotropic plate structures and is very power efficient, with more than an order-of-magnitude power saving

  1. Numerical modelling of local deposition patients, activity distributions and cellular hit probabilities of inhaled radon progenies in human airways

    International Nuclear Information System (INIS)

    Farkas, A.; Balashazy, I.; Szoeke, I.

    2003-01-01

    The general objective of our research is modelling the biophysical processes of the effects of inhaled radon progenies. This effort is related to the rejection or support of the linear no threshold (LNT) dose-effect hypothesis, which seems to be one of the most challenging tasks of current radiation protection. Our approximation and results may also serve as a useful tool for lung cancer models. In this study, deposition patterns, activity distributions and alpha-hit probabilities of inhaled radon progenies in the large airways of the human tracheobronchial tree are computed. The airflow fields and related particle deposition patterns strongly depend on the shape of airway geometry and breathing pattern. Computed deposition patterns of attached an unattached radon progenies are strongly inhomogeneous creating hot spots at the carinal regions and downstream of the inner sides of the daughter airways. The results suggest that in the vicinity of the carinal regions the multiple hit probabilities are quite high even at low average doses and increase exponentially in the low-dose range. Thus, even the so-called low doses may present high doses for large clusters of cells. The cell transformation probabilities are much higher in these regions and this phenomenon cannot be modeled with average burdens. (authors)

  2. Localization, distribution, and connectivity of neuropeptide Y in the human and porcine retinas-A comparative study.

    Science.gov (United States)

    Christiansen, Anders Tolstrup; Kiilgaard, Jens Folke; Klemp, Kristian; Woldbye, David Paul Drucker; Hannibal, Jens

    2018-04-17

    Neuropeptide Y (NPY) is a peptide neurotransmitter abundantly expressed in the mammalian retina. Since its discovery, NPY has been studied in retinas of several species, but detailed characterization of morphology, cell-type, and connectivity has never been conducted in larger mammals including humans and pigs. As the pig due to size and cellular composition is a well-suited animal for retinal research, we chose to compare the endogenous NPY system of the human retina to that of pigs to support future research in this field. In the present study, using immunohistochemistry, confocal microscopy and 3D reconstructions, we found NPY to be expressed in GABAergic and calretinin-immunoreactive (-ir) amacrine cells of both species as well as parvalbumin-ir amacrine cells of humans. Furthermore, we identified at least two different types of medium- to wide-field NPY-ir amacrine cells. Finally, we detected likely synaptic appositions between the NPY-ir amacrine cells and melanopsin- and nonmelanopsin-ir ganglion cells, GABAergic and dopaminergic amacrine cells, rod bipolar cells, and horizontal cells, suggesting that NPY-ir cells play diverse roles in modulation of both image and non-image forming retinal signaling. These findings extend existing knowledge on NPY and NPY-expressing cells in the human and porcine retina showing a high degree of comparability. The extensive distribution and connectivity of NPY-ir cells described in the present study further highlights the potential importance of NPY signaling in retinal function. © 2018 Wiley Periodicals, Inc.

  3. Urban soil geochemistry in Athens, Greece: The importance of local geology in controlling the distribution of potentially harmful trace elements.

    Science.gov (United States)

    Argyraki, Ariadne; Kelepertzis, Efstratios

    2014-06-01

    Understanding urban soil geochemistry is a challenging task because of the complicated layering of the urban landscape and the profound impact of large cities on the chemical dispersion of harmful trace elements. A systematic geochemical soil survey was performed across Greater Athens and Piraeus, Greece. Surface soil samples (0-10cm) were collected from 238 sampling sites on a regular 1×1km grid and were digested by a HNO3-HCl-HClO4-HF mixture. A combination of multivariate statistics and Geographical Information System approaches was applied for discriminating natural from anthropogenic sources using 4 major elements, 9 trace metals, and 2 metalloids. Based on these analyses the lack of heavy industry in Athens was demonstrated by the influence of geology on the local soil chemistry with this accounting for 49% of the variability in the major elements, as well as Cr, Ni, Co, and possibly As (median values of 102, 141, 16 and 24mg kg(-1) respectively). The contribution to soil chemistry of classical urban contaminants including Pb, Cu, Zn, Sn, Sb, and Cd (medians of 45, 39, 98, 3.6, 1.7 and 0.3mg kg(-1) respectively) was also observed; significant correlations were identified between concentrations and urbanization indicators, including vehicular traffic, urban land use, population density, and timing of urbanization. Analysis of soil heterogeneity and spatial variability of soil composition in the Greater Athens and Piraeus area provided a representation of the extent of anthropogenic modifications on natural element loadings. The concentrations of Ni, Cr, and As were relatively high compared to those in other cities around the world, and further investigation should characterize and evaluate their geochemical reactivity. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Integrating local pastoral knowledge, participatory mapping, and species distribution modeling for risk assessment of invasive rubber vine (Cryptostegia grandiflora in Ethiopia's Afar region

    Directory of Open Access Journals (Sweden)

    Matthew W. Luizza

    2016-03-01

    Full Text Available The threats posed by invasive plants span ecosystems and economies worldwide. Local knowledge of biological invasions has proven beneficial for invasive species research, but to date no work has integrated this knowledge with species distribution modeling for invasion risk assessments. In this study, we integrated pastoral knowledge with Maxent modeling to assess the suitable habitat and potential impacts of invasive Cryptostegia grandiflora Robx. Ex R.Br. (rubber vine in Ethiopia's Afar region. We conducted focus groups with seven villages across the Amibara and Awash-Fentale districts. Pastoral knowledge revealed the growing threat of rubber vine, which to date has received limited attention in Ethiopia, and whose presence in Afar was previously unknown to our team. Rubber vine occurrence points were collected in the field with pastoralists and processed in Maxent with MODIS-derived vegetation indices, topographic data, and anthropogenic variables. We tested model fit using a jackknife procedure and validated the final model with an independent occurrence data set collected through participatory mapping activities with pastoralists. A Multivariate Environmental Similarity Surface analysis revealed areas with novel environmental conditions for future targeted surveys. Model performance was evaluated using area under the receiver-operating characteristic curve (AUC and showed good fit across the jackknife models (average AUC = 0.80 and the final model (test AUC = 0.96. Our results reveal the growing threat rubber vine poses to Afar, with suitable habitat extending downstream of its current known location in the middle Awash River basin. Local pastoral knowledge provided important context for its rapid expansion due to acute changes in seasonality and habitat alteration, in addition to threats posed to numerous endemic tree species that provide critical provisioning ecosystem services. This work demonstrates the utility of integrating local

  5. Spatial ecological processes and local factors predict the distribution and abundance of spawning by steelhead (Oncorhynchus mykiss across a complex riverscape.

    Directory of Open Access Journals (Sweden)

    Jeffrey A Falke

    Full Text Available Processes that influence habitat selection in landscapes involve the interaction of habitat composition and configuration and are particularly important for species with complex life cycles. We assessed the relative influence of landscape spatial processes and local habitat characteristics on patterns in the distribution and abundance of spawning steelhead (Oncorhynchus mykiss, a threatened salmonid fish, across ∼15,000 stream km in the John Day River basin, Oregon, USA. We used hurdle regression and a multi-model information theoretic approach to identify the relative importance of covariates representing key aspects of the steelhead life cycle (e.g., site access, spawning habitat quality, juvenile survival at two spatial scales: within 2-km long survey reaches (local sites and ecological neighborhoods (5 km surrounding the local sites. Based on Akaike's Information Criterion, models that included covariates describing ecological neighborhoods provided the best description of the distribution and abundance of steelhead spawning given the data. Among these covariates, our representation of offspring survival (growing-season-degree-days, °C had the strongest effect size (7x relative to other predictors. Predictive performances of model-averaged composite and neighborhood-only models were better than a site-only model based on both occurrence (percentage of sites correctly classified = 0.80±0.03 SD, 0.78±0.02 vs. 0.62±0.05, respectively and counts (root mean square error = 3.37, 3.93 vs. 5.57, respectively. The importance of both temperature and stream flow for steelhead spawning suggest this species may be highly sensitive to impacts of land and water uses, and to projected climate impacts in the region and that landscape context, complementation, and connectivity will drive how this species responds to future environments.

  6. Localization Accuracy of Distributed Inverse Solutions for Electric and Magnetic Source Imaging of Interictal Epileptic Discharges in Patients with Focal Epilepsy.

    Science.gov (United States)

    Heers, Marcel; Chowdhury, Rasheda A; Hedrich, Tanguy; Dubeau, François; Hall, Jeffery A; Lina, Jean-Marc; Grova, Christophe; Kobayashi, Eliane

    2016-01-01

    Distributed inverse solutions aim to realistically reconstruct the origin of interictal epileptic discharges (IEDs) from noninvasively recorded electroencephalography (EEG) and magnetoencephalography (MEG) signals. Our aim was to compare the performance of different distributed inverse solutions in localizing IEDs: coherent maximum entropy on the mean (cMEM), hierarchical Bayesian implementations of independent identically distributed sources (IID, minimum norm prior) and spatially coherent sources (COH, spatial smoothness prior). Source maxima (i.e., the vertex with the maximum source amplitude) of IEDs in 14 EEG and 19 MEG studies from 15 patients with focal epilepsy were analyzed. We visually compared their concordance with intracranial EEG (iEEG) based on 17 cortical regions of interest and their spatial dispersion around source maxima. Magnetic source imaging (MSI) maxima from cMEM were most often confirmed by iEEG (cMEM: 14/19, COH: 9/19, IID: 8/19 studies). COH electric source imaging (ESI) maxima co-localized best with iEEG (cMEM: 8/14, COH: 11/14, IID: 10/14 studies). In addition, cMEM was less spatially spread than COH and IID for ESI and MSI (p < 0.001 Bonferroni-corrected post hoc t test). Highest positive predictive values for cortical regions with IEDs in iEEG could be obtained with cMEM for MSI and with COH for ESI. Additional realistic EEG/MEG simulations confirmed our findings. Accurate spatially extended sources, as found in cMEM (ESI and MSI) and COH (ESI) are desirable for source imaging of IEDs because this might influence surgical decision. Our simulations suggest that COH and IID overestimate the spatial extent of the generators compared to cMEM.

  7. Measures of Dependence for α-Stable Distributed Processes and Its Application to Diagnostics of Local Damage in Presence of Impulsive Noise

    Directory of Open Access Journals (Sweden)

    Grzegorz Żak

    2017-01-01

    Full Text Available Local damage detection in rotating machinery is simply searching for cyclic impulsive signal in noisy observation. Such raw signal is mixture of various components with specific properties (deterministic, random, cyclic, impulsive, etc.. The problem appears when the investigated process is based on one of the heavy-tailed distributions. In this case the classical measure can not be considered. Therefore, alternative measures of dependence adequate for such processes should be considered. In this paper we examine the structure of dependence of alpha-stable based systems expressed by means of two measures, namely, codifference and covariation. The reason for using alpha-stable distribution is simple and intuitive: signal of interest is impulsive so its distribution is heavy-tailed. The main goal is to introduce a new technique for estimation of covariation. Due to the complex nature of such vibration signals applying novel methods instead of classical ones is recommended. Classical algorithms usually are based on the assumption that theoretical second moment is finite, which is not true in case of the data acquired on the faulty components. Main advantage of our proposed algorithm is independence from second moment assumption.

  8. A User-Adaptive Algorithm for Activity Recognition Based on K-Means Clustering, Local Outlier Factor, and Multivariate Gaussian Distribution

    Directory of Open Access Journals (Sweden)

    Shizhen Zhao

    2018-06-01

    Full Text Available Mobile activity recognition is significant to the development of human-centric pervasive applications including elderly care, personalized recommendations, etc. Nevertheless, the distribution of inertial sensor data can be influenced to a great extent by varying users. This means that the performance of an activity recognition classifier trained by one user’s dataset will degenerate when transferred to others. In this study, we focus on building a personalized classifier to detect four categories of human activities: light intensity activity, moderate intensity activity, vigorous intensity activity, and fall. In order to solve the problem caused by different distributions of inertial sensor signals, a user-adaptive algorithm based on K-Means clustering, local outlier factor (LOF, and multivariate Gaussian distribution (MGD is proposed. To automatically cluster and annotate a specific user’s activity data, an improved K-Means algorithm with a novel initialization method is designed. By quantifying the samples’ informative degree in a labeled individual dataset, the most profitable samples can be selected for activity recognition model adaption. Through experiments, we conclude that our proposed models can adapt to new users with good recognition performance.

  9. Community Composition and Ultrastructure of a Nitrate-Dependent Anaerobic Methane-Oxidizing Enrichment Culture.

    Science.gov (United States)

    Gambelli, Lavinia; Guerrero-Cruz, Simon; Mesman, Rob J; Cremers, Geert; Jetten, Mike S M; Op den Camp, Huub J M; Kartal, Boran; Lueke, Claudia; van Niftrik, Laura

    2018-02-01

    Methane is a very potent greenhouse gas and can be oxidized aerobically or anaerobically through microbe-mediated processes, thus decreasing methane emissions in the atmosphere. Using a complementary array of methods, including phylogenetic analysis, physiological experiments, and light and electron microscopy techniques (including electron tomography), we investigated the community composition and ultrastructure of a continuous bioreactor enrichment culture, in which anaerobic oxidation of methane (AOM) was coupled to nitrate reduction. A membrane bioreactor was seeded with AOM biomass and continuously fed with excess methane. After 150 days, the bioreactor reached a daily consumption of 10 mmol nitrate · liter -1 · day -1 The biomass consisted of aggregates that were dominated by nitrate-dependent anaerobic methane-oxidizing " Candidatus Methanoperedens"-like archaea (40%) and nitrite-dependent anaerobic methane-oxidizing " Candidatus Methylomirabilis"-like bacteria (50%). The " Ca Methanoperedens" spp. were identified by fluorescence in situ hybridization and immunogold localization of the methyl-coenzyme M reductase (Mcr) enzyme, which was located in the cytoplasm. The " Ca Methanoperedens" sp. aggregates consisted of slightly irregular coccoid cells (∼1.5-μm diameter) which produced extruding tubular structures and putative cell-to-cell contacts among each other. " Ca Methylomirabilis" sp. bacteria exhibited the polygonal cell shape typical of this genus. In AOM archaea and bacteria, cytochrome c proteins were localized in the cytoplasm and periplasm, respectively, by cytochrome staining. Our results indicate that AOM bacteria and archaea might work closely together in the process of anaerobic methane oxidation, as the bacteria depend on the archaea for nitrite. Future studies will be aimed at elucidating the function of the cell-to-cell interactions in nitrate-dependent AOM. IMPORTANCE Microorganisms performing nitrate- and nitrite-dependent anaerobic

  10. Histology and ultrastructure of the integumental chromatophores in tokay gecko (Gekko gecko) (Linnaeus, 1758) skin.

    Science.gov (United States)

    Szydłowski, Paweł; Madej, Jan Paweł; Mazurkiewicz-Kania, Marta

    2017-01-01

    This paper describes the relationship between the arrangement of dermal chromatophores in tokay gecko ( Gekko gecko ) skin and the formation of wild-type colouration, with emphasis on the ultrastructure of chromatophores. The samples of the tokay gecko skin were collected from wild-type colouration adult specimens. Morphology and distribution of chromatophores was determined by using light microscopy and transmission electron microscopy. The present study revealed that orange/red coloured skin of G. gecko contained erythrophores, which were located under basement membrane, and usually comprised deeper situated iridophores and melanophores which were form single layer with iridophores or were occupying the deepest region of dermis. In orange/red coloured skin, erythrophores were the predominant chromatophores. However in blue areas these cells occurred in small numbers or were not noticed at all. In blue pigmented areas predominated iridophores and melanophores. Iridophores were found just under basement membrane, but this superficial location of iridophores occured only in areas without erythrophores. Distribution of erythrophores, melanophores, and iridophores determines the characteristic blue colour of the tokay gecko skin with orange/red dots on the whole body.

  11. First ultrastructural data on the human tapeworm Taenia asiatica eggs by scanning and transmission electron microscopy (SEM, TEM).

    Science.gov (United States)

    Galán-Puchades, M Teresa; Yang, Yichao; Marcilla, Antonio; Choe, Seongjun; Park, Hansol; Osuna, Antonio; Eom, Keeseon S

    2016-09-01

    Humans are definitive hosts of three species of the Taenia genus, namely Taenia solium, Taenia saginata and Taenia asiatica. The relative novelty of the latter explains the lack of knowledge concerning certain relevant aspects related to this parasite, such as its definite geographical distribution and whether its eggs can infect humans or not. So far, only the eggs of T. solium are known to be infective for humans, producing cysticercosis. Although eggs contain the infective stage, the oncosphere, there is a lack of research on the ultrastructure of eggs of human taeniids. We show, for the first time, the ultrastructure of eggs of T. asiatica by means of SEM and TEM analyses. We detected all the envelopes, namely the egg shell, vitelline layer, outer embryophoric membrane, embryophore, granular layer, basal membrane, oncospheral membrane and oncospheral tegument. Hooks surrounded by myofibrils and glycogen-like particles, the two types of secretory granules of the penetration glands, as well as several nuclei and mitochondria were also revealed in the oncospheres. In addition to the already known structures in eggs from other Taenia species, the presence of two types of small vesicles is described herein, possibly corresponding to exosomes and ectosomes because of their shape and size, which could participate in the host/parasite intercellular communication.

  12. Transmission electron microscopy, fluorescence microscopy, and confocal raman microscopic analysis of ultrastructural and compositional heterogeneity of Cornus alba L. wood cell wall.

    Science.gov (United States)

    Ma, Jianfeng; Ji, Zhe; Zhou, Xia; Zhang, Zhiheng; Xu, Feng

    2013-02-01

    Transmission electron microscopy (TEM), fluorescence microscopy, and confocal Raman microscopy can be used to characterize ultrastructural and compositional heterogeneity of plant cell walls. In this study, TEM observations revealed the ultrastructural characterization of Cornus alba L. fiber, vessel, axial parenchyma, ray parenchyma, and pit membrane between cells, notably with the ray parenchyma consisting of two well-defined layers. Fluorescence microscopy evidenced that cell corner midd