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Sample records for lamina strengthens cell

  1. Robust nuclear lamina-based cell classification of aging and senescent cells.

    Science.gov (United States)

    Righolt, Christiaan H; van 't Hoff, Merel L R; Vermolen, Bart J; Young, Ian T; Raz, Vered

    2011-12-01

    Changes in the shape of the nuclear lamina are exhibited in senescent cells, as well as in cells expressing mutations in lamina genes. To identify cells with defects in the nuclear lamina we developed an imaging method that quantifies the intensity and curvature of the nuclear lamina. We show that this method accurately describes changes in the nuclear lamina. Spatial changes in nuclear lamina coincide with redistribution of lamin A proteins and local reduction in protein mobility in senescent cell. We suggest that local accumulation of lamin A in the nuclear envelope leads to bending of the structure. A quantitative distinction of the nuclear lamina shape in cell populations was found between fresh and senescent cells, and between primary myoblasts from young and old donors. Moreover, with this method mutations in lamina genes were significantly distinct from cells with wild-type genes. We suggest that this method can be applied to identify abnormal cells during aging, in in vitro propagation, and in lamina disorders.

  2. Genome-Nuclear Lamina Interactions Regulate Cardiac Stem Cell Lineage Restriction.

    Science.gov (United States)

    Poleshko, Andrey; Shah, Parisha P; Gupta, Mudit; Babu, Apoorva; Morley, Michael P; Manderfield, Lauren J; Ifkovits, Jamie L; Calderon, Damelys; Aghajanian, Haig; Sierra-Pagán, Javier E; Sun, Zheng; Wang, Qiaohong; Li, Li; Dubois, Nicole C; Morrisey, Edward E; Lazar, Mitchell A; Smith, Cheryl L; Epstein, Jonathan A; Jain, Rajan

    2017-10-19

    Progenitor cells differentiate into specialized cell types through coordinated expression of lineage-specific genes and modification of complex chromatin configurations. We demonstrate that a histone deacetylase (Hdac3) organizes heterochromatin at the nuclear lamina during cardiac progenitor lineage restriction. Specification of cardiomyocytes is associated with reorganization of peripheral heterochromatin, and independent of deacetylase activity, Hdac3 tethers peripheral heterochromatin containing lineage-relevant genes to the nuclear lamina. Deletion of Hdac3 in cardiac progenitor cells releases genomic regions from the nuclear periphery, leading to precocious cardiac gene expression and differentiation into cardiomyocytes; in contrast, restricting Hdac3 to the nuclear periphery rescues myogenesis in progenitors otherwise lacking Hdac3. Our results suggest that availability of genomic regions for activation by lineage-specific factors is regulated in part through dynamic chromatin-nuclear lamina interactions and that competence of a progenitor cell to respond to differentiation signals may depend upon coordinated movement of responding gene loci away from the nuclear periphery. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Electron microscopic observation of 137Cs-irradiated rat testis. Production of basal laminae for germ cells, despite their absence

    International Nuclear Information System (INIS)

    Sawada, Hajime; Esaki, Michiyo

    2003-01-01

    Whole body γ-ray irradiation of rats with caesium-137 ( 137 Cs) at embryonic day 20 induced marked reduction of the weight of the testis. Body weight and other tissues, however, seemed to remain normal. By light microscopy, complete loss of germ cells was observed in the testis. Other components, such as Sertoli cells and interstitial cells, seemed to be normal. The testes from day 8 postpartum rats contained very few spermatogonia compared with newborn rats, indicating loss of germ cells between days 0 and 8. In the adult, 137 Cs-irradiated testes showed two conspicuous features other than the loss of germ cells: empty vacuolar spaces between Sertoli cells and multilayered seminiferous tubule basal laminae (lamina densa). The junctional structures (ectoplasmic specializations) between Sertoli cells, however, seemed normal. The thickness of each layer of multilayered basal laminae was the same as that of normal rats and electron-lucent layers similar to lamina lucida were interposed between them. Of the empty vacuolar spaces between Sertoli cells, basal laminae bridge the gap. The basal laminae contained laminin, type IV collagen and heparan sulphate proteoglycan evenly distributed among layers, suggesting a normal composition. Rough estimation of the amount of basal laminae deposited in 137 Cs-irradiated rats indicates that it is within a range similar to that in normal testis. These features imply that Sertoli cells are, in part, determined perinatally to produce basal laminae for germ-line cells. (author)

  4. Proliferation and apoptosis of lamina propria CD4+ T cells from scid mice with inflammatory bowel disease

    DEFF Research Database (Denmark)

    Bregenholt, S; Reimann, J; Claesson, Mogens Helweg

    1998-01-01

    Scid mice transplanted with low numbers of syngeneic CD4+ T cells, develop a chronic and lethal inflammatory bowel disease (IBD) within 4-6 months. We have used in vivo 5-bromo2-deoxy-uridine (BrdU) labeling to assess the proliferation of lamina propria-derived CD4+ T cells in diseased scid mice....... The hourly rate of renewal of colonic lamina propria CD4+ T cells in diseased mice was 7% compared with 1.5% in normal BALB/c control mice. Transplantation of scid mice with in vitro activated CD4+ T cells accelerated the disease onset and development in a cell dose-dependent fashion when compared with non......-activated CD4+ T cells. In pulse-chase experiments it was shown that BrdU-labeled cells disappeared rapidly from the lamina propria of diseased mice. DNA analysis revealed that this was due to the presence of nearly four times as many apoptotic CD4+ T cells in diseased than in control mice. Further analyses...

  5. The majority of lamina propria CD4(+) T-cells from scid mice with colitis undergo Fas-mediated apoptosis in vivo

    DEFF Research Database (Denmark)

    Bregenholt, S; Petersen, T R; Claesson, Mogens Helweg

    2001-01-01

    We have previously shown that adoptively transferred CD4(+) T-cells mediate an chronic colitis in severe combined immune deficient (scid) mice. Colitis is accompanied by activation and apoptosis of Fas ligand and TNF-alpha expressing CD4(+) T-cells in the diseased colonic lamina propria (Eur. J....... Immunol. 28:3655 (1998)). Here we investigate the apoptosis-inducing mechanism in these lamina propria infiltrating CD4(+) T-cells. We observe that freshly isolated lamina propria CD4(+) T-cells can kill Fas transfected P815 mastocytoma cells in a TCR/CD3 redirected chromium-release assay, but do...... not express TNF-alpha mediated cytotoxicity. Pre-incubation of the isolated lamina propria CD4(+) T-cells with an anti-FasL antiserum partially blocked killing of the Fas transfected target cells, indicating a role for the Fas-FasL system in the killing process. Treatment of scid mice with colitis with anti-Fas...

  6. Fate of the Molar Dental Lamina in the Monophyodont Mouse

    Science.gov (United States)

    Dosedělová, Hana; Dumková, Jana; Lesot, Hervé; Glocová, Kristýna; Kunová, Michaela; Tucker, Abigail S.; Veselá, Iva; Krejčí, Pavel; Tichý, František; Hampl, Aleš; Buchtová, Marcela

    2015-01-01

    The successional dental lamina (SDL) plays an essential role in the development of replacement teeth in diphyodont and polyphyodont animals. A morphologically similar structure, the rudimental successional dental lamina (RSDL), has been described in monophyodont (only one tooth generation) lizards on the lingual side of the developing functional tooth. This rudimentary lamina regresses, which has been proposed to play a role in preventing the formation of future generations of teeth. A similar rudimentary lingual structure has been reported associated with the first molar in the monophyodont mouse, and we show that this structure is common to all murine molars. Intriguingly, a lingual lamina is also observed on the non-replacing molars of other diphyodont mammals (pig and hedgehog), initially appearing very similar to the successional dental lamina on the replacing teeth. We have analyzed the morphological as well as ultrastructural changes that occur during the development and loss of this molar lamina in the mouse, from its initiation at late embryonic stages to its disappearance at postnatal stages. We show that loss appears to be driven by a reduction in cell proliferation, down-regulation of the progenitor marker Sox2, with only a small number of cells undergoing programmed cell death. The lingual lamina was associated with the dental stalk, a short epithelial connection between the tooth germ and the oral epithelium. The dental stalk remained in contact with the oral epithelium throughout tooth development up to eruption when connective tissue and numerous capillaries progressively invaded the dental stalk. The buccal side of the dental stalk underwent keratinisation and became part of the gingival epithelium, while most of the lingual cells underwent programmed cell death and the tissue directly above the erupting tooth was shed into the oral cavity. PMID:26010446

  7. Significance of host cell kinases in herpes simplex virus type 1 egress and lamin-associated protein disassembly from the nuclear lamina

    International Nuclear Information System (INIS)

    Leach, Natalie R.; Roller, Richard J.

    2010-01-01

    The nuclear lamina is thought to be a steric barrier to the herpesvirus capsid. Disruption of the lamina accompanied by phosphorylation of lamina proteins is a conserved feature of herpesvirus infection. In HSV-1-infected cells, protein kinase C (PKC) alpha and delta isoforms are recruited to the nuclear membrane and PKC delta has been implicated in phosphorylation of emerin and lamin B. We tested two critical hypotheses about the mechanism and significance of lamina disruption. First, we show that chemical inhibition of all PKC isoforms reduced viral growth five-fold and inhibited capsid egress from the nucleus. However, specific inhibition of either conventional PKCs or PKC delta does not inhibit viral growth. Second, we show hyperphosphorylation of emerin by viral and cellular kinases is required for its disassociation from the lamina. These data support hypothesis that phosphorylation of lamina components mediates lamina disruption during HSV nuclear egress.

  8. Cytotoxic reactivity of gut lamina propria CD4+ alpha beta T cells in SCID mice with colitis

    DEFF Research Database (Denmark)

    Bonhagen, K; Thoma, S; Bland, P

    1996-01-01

    Polyclonal, mucosa-seeking memory/effector CD4+ T cells containing a large fraction of blasts activated in situ accumulate in the gut lamina propria of severe-combined immunodeficient (SCID) mice developing colitis after CD4+ T cell transplantation. CD4+ T cells isolated from different repopulated...

  9. Repopulation with IgA-containing cells of bronchial and intestinal lamina propria after transfer of homologous peyer's patch and bronchial lymphocytes

    International Nuclear Information System (INIS)

    Rudzik, R.; Clancy, R.L.; Perey, D.Y.E.; Day, R.P.; Bienenstock, J.

    1975-01-01

    Transfer of 50 million rabbit allogeneic lymphocytes from either bronchus-associated lymphoid tissue (BALT) or Peyer's patches into 1000 R x-irradiated recipients results, 6 days later, in predominant repopulation of gut and bronchial lamina propria, as well as spleen, with IgA-containing cells. After repopulation with BALT or Peyer's patch cells, lymphoid follicles in both gut and lung showed peripheral cellular membrane type of fluorescence with fluorescein-conjugated anti-IgA antisera only. Six days after x-irradiation alone, little evidence of repopulation was seen and immunofluorescent qualitative observations of gut and lung, and quantitative data in the spleen, confirmed these findings. After transfer of 50 million lymph node cells, very few immunoglobulin-containing cells were seen in the gut or bronchial lamina propria. These results suggest that there may be a common mucosal immunologic system, and that repopulation of gut and lung lamina propria may be through the organized lymphoid tissue therein. (U.S.)

  10. Quantification of the spatial organization of the nuclear lamina as a tool for cell classification

    NARCIS (Netherlands)

    Righolt, C.H.; Zatreanu, D.A.; Raz, V.

    2013-01-01

    The nuclear lamina is the structural scaffold of the nuclear envelope that plays multiple regulatory roles in chromatin organization and gene expression as well as a structural role in nuclear stability. The lamina proteins, also referred to as lamins, determine nuclear lamina organization and

  11. Isolation of Eosinophils from the Lamina Propria of the Murine Small Intestine.

    Science.gov (United States)

    Berek, Claudia; Beller, Alexander; Chu, Van Trung

    2016-01-01

    Only recently has it become apparent that eosinophils play a crucial role in mucosal immune homeostasis. Although eosinophils are the main cellular component of the lamina propria of the gastrointestinal tract, they have often been overlooked because they express numerous markers, which are normally used to characterize macrophages and/or dendritic cells. To study their function in mucosal immunity, it is important to isolate them with high purity and viability. Here, we describe a protocol to purify eosinophils from the lamina propria of the murine small intestine. The method involves preparation of the small intestine, removal of epithelial cells and digestion of the lamina propria to release eosinophils. A protocol to sort eosinophils is included.

  12. Activation of stretch-activated channels and maxi-K+ channels by membrane stress of human lamina cribrosa cells.

    LENUS (Irish Health Repository)

    Irnaten, Mustapha

    2009-01-01

    The lamina cribrosa (LC) region of the optic nerve head is considered the primary site of damage in glaucomatous optic neuropathy. Resident LC cells have a profibrotic potential when exposed to cyclical stretch. However, the mechanosensitive mechanisms of these cells remain unknown. Here the authors investigated the effects of membrane stretch on cell volume change and ion channel activity and examined the associated changes in intracellular calcium ([Ca(2+)](i)).

  13. Galanin-immunoreactivity identifies a distinct population of inhibitory interneurons in laminae I-III of the rat spinal cord

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    Watanabe Masahiko

    2011-05-01

    Full Text Available Abstract Background Inhibitory interneurons constitute 30-40% of neurons in laminae I-III and have an important anti-nociceptive role. However, because of the difficulty in classifying them we know little about their organisation. Previous studies have identified 3 non-overlapping groups of inhibitory interneuron, which contain neuropeptide Y (NPY, neuronal nitric oxide synthase (nNOS or parvalbumin, and have shown that these differ in postsynaptic targets. Some inhibitory interneurons contain galanin and the first aim of this study was to determine whether these form a different population from those containing NPY, nNOS or parvalbumin. We also estimated the proportion of neurons and GABAergic axons that contain galanin in laminae I-III. Results Galanin cells were concentrated in laminae I-IIo, with few in laminae IIi-III. Galanin showed minimal co-localisation with NPY, nNOS or parvalbumin in laminae I-II, but most galanin-containing cells in lamina III were nNOS-positive. Galanin cells constituted ~7%, 3% and 2% of all neurons in laminae I, II and III, and we estimate that this corresponds to 26%, 10% and 5% of the GABAergic neurons in these laminae. However, galanin was only found in ~6% of GABAergic boutons in laminae I-IIo, and ~1% of those in laminae IIi-III. Conclusions These results show that galanin, NPY, nNOS and parvalbumin can be used to define four distinct neurochemical populations of inhibitory interneurons. Together with results of a recent study, they suggest that the galanin and NPY populations account for around half of the inhibitory interneurons in lamina I and a quarter of those in lamina II.

  14. Neutrophil migration through preexisting holes in the basal laminae of alveolar capillaries and epithelium during streptococcal pneumonia.

    Science.gov (United States)

    Walker, D C; Behzad, A R; Chu, F

    1995-11-01

    The purpose of this study was to determine whether or not there are preexisting holes in the endothelial and epithelial basal laminae of alveolar walls and to determine the path taken by neutrophils as they migrate from the capillaries to the airspace of the alveoli during inflammation. Using transmission electron microscopy and serial thin sections of normal rabbit and mouse lung, we have demonstrated the presence of slit-like holes in the capillary basal laminae and round holes in the basal laminae of type 2 pneumocytes. The slits in the capillary basal laminae were observed at the intersection of the thick and thin walls where endothelium, pericytes, and fibroblasts make close contact. The round holes in the type 2 cell basal laminae were observed at sites of close contact with fibroblasts. Neutrophils were observed to migrate through these slits and holes during streptococcal pneumonia in rabbit lungs. We conclude that during inflammation in the lung, migrating neutrophils displace pericytes and fibroblasts from the slits in the capillary basal lamina and then crawl through these slits into the alveolar interstitium. We postulate that neutrophils find their way to type 2 pneumocytes by following interstitial fibroblasts. We believe that neutrophils displace fibroblasts from their close contacts with the type 2 cells and then crawl through the holes in the basal lamina into the basal lateral space of the type 2 cells. From there, neutrophils migrate into the alveolar airspace.

  15. Isolation and Flow Cytometry Analysis of Innate Lymphoid Cells from the Intestinal Lamina Propria.

    Science.gov (United States)

    Gronke, Konrad; Kofoed-Nielsen, Michael; Diefenbach, Andreas

    2017-01-01

    The intestinal mucosa constitutes the biggest surface area of the body. It is constantly challenged by bacteria, commensal and pathogenic, protozoa, and food-derived irritants. In order to maintain homeostasis, a complex network of signaling circuits has evolved that includes contributions of immune cells. In recent years a subset of lymphocytes, which belong to the innate immune system, has caught particular attention. These so-called innate lymphoid cells (ILC) reside within the lamina propria of the small and large intestines and rapidly respond to environmental challenges. They provide immunity to various types of infections but may also contribute to organ homeostasis as they produce factors acting on epithelial cells thereby enhancing barrier integrity. Here, we describe how these cells can be isolated from their environment and provide an in-depth protocol how to visualize the various ILC subsets by flow cytometry.

  16. Transient and Partial Nuclear Lamina Disruption Promotes Chromosome Movement in Early Meiotic Prophase.

    Science.gov (United States)

    Link, Jana; Paouneskou, Dimitra; Velkova, Maria; Daryabeigi, Anahita; Laos, Triin; Labella, Sara; Barroso, Consuelo; Pacheco Piñol, Sarai; Montoya, Alex; Kramer, Holger; Woglar, Alexander; Baudrimont, Antoine; Markert, Sebastian Mathias; Stigloher, Christian; Martinez-Perez, Enrique; Dammermann, Alexander; Alsheimer, Manfred; Zetka, Monique; Jantsch, Verena

    2018-04-23

    Meiotic chromosome movement is important for the pairwise alignment of homologous chromosomes, which is required for correct chromosome segregation. Movement is driven by cytoplasmic forces, transmitted to chromosome ends by nuclear membrane-spanning proteins. In animal cells, lamins form a prominent scaffold at the nuclear periphery, yet the role lamins play in meiotic chromosome movement is unclear. We show that chromosome movement correlates with reduced lamin association with the nuclear rim, which requires lamin phosphorylation at sites analogous to those that open lamina network crosslinks in mitosis. Failure to remodel the lamina results in delayed meiotic entry, altered chromatin organization, unpaired or interlocked chromosomes, and slowed chromosome movement. The remodeling kinases are delivered to lamins via chromosome ends coupled to the nuclear envelope, potentially enabling crosstalk between the lamina and chromosomal events. Thus, opening the lamina network plays a role in modulating contacts between chromosomes and the nuclear periphery during meiosis. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

  17. Mechanisms of nuclear lamina growth in interphase

    Czech Academy of Sciences Publication Activity Database

    Zhironkina, O.A.; Kurchashova, S.Y.; Pozharskaia, V.A.; Cherepanynets, V.D.; Strelkova, O.S.; Hozák, Pavel; Kireev, I.I.

    2016-01-01

    Roč. 145, č. 4 (2016), s. 419-432 ISSN 0948-6143 R&D Projects: GA ČR GA16-03403S Grant - others:Russian Fund for Basic Research(RU) 13-04-00885; Russian Fund for Basic Research(RU) 15-54-78077 Institutional support: RVO:68378050 Keywords : Nuclear lamina * Microdomains * Interphase * Nucleus * DNA replication * Cell cycle Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.553, year: 2016

  18. The influence of the level of lamina propria invasion and the prevalence of p53 nuclear accumulation on survival in stage T1 transitional cell bladder cancer

    DEFF Research Database (Denmark)

    Hermann, G G; Horn, T; Steven, K

    1998-01-01

    PURPOSE: We assessed the influence of the level of lamina propria invasion and the prevalence of p53 nuclear immunoreactivity on the survival of patients with stage T1 transitional cell bladder cancer. MATERIALS AND METHODS: All patients presenting with stage T1 bladder cancer were prospectively...... and routinely grouped according to the level of lamina propria invasion. Invasion of the tumor stalk was defined as stage T1a, invasion of the lamina propria proper superficial to the level of muscularis mucosa as stage T1b and into or deeper than the muscularis mucosa as stage T1c. The p53 nuclear...... related to age, level of lamina propria invasion and presence of p53 nuclear accumulation. For this subpopulation overall survival was 67%, and 79% for stage T1a, 70% for stage T1b and 57% for stage T1c (p

  19. Phosphorylation of ERK in neurokinin 1 receptor-expressing neurons in laminae III and IV of the rat spinal dorsal horn following noxious stimulation

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    Watanabe Masahiko

    2007-02-01

    Full Text Available Abstract Background There is a population of large neurons with cell bodies in laminae III and IV of the spinal dorsal horn which express the neurokinin 1 receptor (NK1r and have dendrites that enter the superficial laminae. Although it has been shown that these are all projection neurons and that they are innervated by substance P-containing (nociceptive primary afferents, we know little about their responses to noxious stimuli. In this study we have looked for phosphorylation of extracellular signal-regulated kinases (ERKs in these neurons in response to different types of noxious stimulus applied to one hindlimb of anaesthetised rats. The stimuli were mechanical (repeated pinching, thermal (immersion in water at 52°C or chemical (injection of 2% formaldehyde. Results Five minutes after each type of stimulus we observed numerous cells with phosphorylated ERK (pERK in laminae I and IIo, together with scattered positive cells in deeper laminae. We found that virtually all of the lamina III/IV NK1r-immunoreactive neurons contained pERK after each of these stimuli and that in the great majority of cases there was internalisation of the NK1r on the dorsal dendrites of these cells. In addition, we also saw neurons in lamina III that were pERK-positive but lacked the NK1r, and these were particularly evident in animals that had had the pinch stimulus. Conclusion Our results demonstrate that lamina III/IV NK1r-immunoreactive neurons show receptor internalisation and ERK phosphorylation after mechanical, thermal or chemical noxious stimuli.

  20. Characterizing lamina propria of human gastric mucosa by multiphoton microscopy

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    Liu, Y C; Yang, H Q; Zhuo, S M [Institute of Laser and Optoelectronics Technology, Fujian Provincial Key Laboratory for Photonics Technology, Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, Fujian Normal University, Fuzhou 350007 (China); Chen, G; Chen, J X [Department of Pathology, Fujian Provincial Tumor Hospital, Fuzhou, 350014 (China); Yan, J, E-mail: chenjianxin@fjnu.edu.cn, E-mail: ynjun@yahoo.com [Department of Surgery, Fujian Provincial Tumor Hospital, Fuzhou, 350014 (China)

    2011-01-01

    Lamina propria (LP) of gastric mucosa plays an important role in progression of gastric cancer because of the site at where inflammatory reactions occur. Multiphoton imaging has been recently employed for microscopic examination of intact tissue. In this paper, using multiphoton microscopy (MPM) based on two-photon excited fluorescence (TPEF) and second harmonic generation (SHG), high resolution multiphoton microscopic images of lamina propria (LP) are obtained in normal human gastric mucosa at excitation wavelength {lambda}{sub ex} = 800 nm. The main source of tissue TPEF originated from the cells of gastric glands, and loose connective tissue, collagen, produced SHG signals. Our results demonstrated that MPM can be effective for characterizing the microstructure of LP in human gastric mucosa. The findings will be helpful for diagnosing and staging early gastric cancer in the clinics.

  1. Characterizing lamina propria of human gastric mucosa by multiphoton microscopy

    Science.gov (United States)

    Liu, Y. C.; Yang, H. Q.; Chen, G.; Zhuo, S. M.; Chen, J. X.; Yan, J.

    2011-01-01

    Lamina propria (LP) of gastric mucosa plays an important role in progression of gastric cancer because of the site at where inflammatory reactions occur. Multiphoton imaging has been recently employed for microscopic examination of intact tissue. In this paper, using multiphoton microscopy (MPM) based on two-photon excited fluorescence (TPEF) and second harmonic generation (SHG), high resolution multiphoton microscopic images of lamina propria (LP) are obtained in normal human gastric mucosa at excitation wavelength λex = 800 nm. The main source of tissue TPEF originated from the cells of gastric glands, and loose connective tissue, collagen, produced SHG signals. Our results demonstrated that MPM can be effective for characterizing the microstructure of LP in human gastric mucosa. The findings will be helpful for diagnosing and staging early gastric cancer in the clinics.

  2. Eosinophils from Murine Lamina Propria Induce Differentiation of Naïve T Cells into Regulatory T Cells via TGF-β1 and Retinoic Acid.

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    Hong-Hu Chen

    Full Text Available Treg cells play a crucial role in immune tolerance, but mechanisms that induce Treg cells are poorly understood. We here have described eosinophils in lamina propria (LP that displayed high aldehyde dehydrogenase (ALDH activity, a rate-limiting step during all-trans retinoic acid (ATRA synthesis, and expressed TGF-β1 mRNA and high levels of ATRA. Co-incubation assay confirmed that LP eosinophils induced the differentiation of naïve T cells into Treg cells. Differentiation promoted by LP eosinophils were inhibited by blocked either TGF-β1 or ATRA. Peripheral blood (PB eosinophils did not produce ATRA and could not induce Treg differentiation. These data identifies LP eosinophils as effective inducers of Treg cell differentiation through a mechanism dependent on TGF-β1 and ATRA.

  3. Functional Characterization of Lamina X Neurons in ex-Vivo Spinal Cord Preparation

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    Volodymyr Krotov

    2017-11-01

    Full Text Available Functional properties of lamina X neurons in the spinal cord remain unknown despite the established role of this area for somatosensory integration, visceral nociception, autonomic regulation and motoneuron output modulation. Investigations of neuronal functioning in the lamina X have been hampered by technical challenges. Here we introduce an ex-vivo spinal cord preparation with both dorsal and ventral roots still attached for functional studies of the lamina X neurons and their connectivity using an oblique LED illumination for resolved visualization of lamina X neurons in a thick tissue. With the elaborated approach, we demonstrate electrophysiological characteristics of lamina X neurons by their membrane properties, firing pattern discharge and fiber innervation (either afferent or efferent. The tissue preparation has been also probed using Ca2+ imaging with fluorescent Ca2+ dyes (membrane-impermeable or -permeable to demonstrate the depolarization-induced changes in intracellular calcium concentration in lamina X neurons. Finally, we performed visualization of subpopulations of lamina X neurons stained by retrograde labeling with aminostilbamidine dye to identify sympathetic preganglionic and projection neurons in the lamina X. Thus, the elaborated approach provides a reliable tool for investigation of functional properties and connectivity in specific neuronal subpopulations, boosting research of lamina X of the spinal cord.

  4. Direct and indirect pathways to lamina I in the medulla oblongata and spinal cord of the cat

    Science.gov (United States)

    Holstege, Gert

    1988-01-01

    The pathways to lamina I in the medulla oblongata and spinal cord of the cat were traced using horse-radish-peroxidase (HRP) and autoradiographic techniques. The HRP results indicated that several neuronal cell groups in the brain stem and hypothalamus project to the spinal cord throughout its total length. The autoradiographic tracing results demonstrated that the strongest projections to lamina I are derived from the following four areas: the caudal nucleus raphe magnus (NRM), the ventral part of the caudal pontine and NRM, the contralaterally projecting lateral pontine or paralemniscal tegmentum, and the paraventricular nucleus of the hypothalamus. In addition, a limited, especially at lumbosacral levels, distinct projection to lamina I was found to originate in the most caudal part of the medullary tegmentum.

  5. An IFNG SNP with an estrogen-like response element selectively enhances promoter expression in peripheral but not lamina propria T cells.

    Science.gov (United States)

    Gonsky, R; Deem, R L; Bream, J H; Young, H A; Targan, S R

    2006-07-01

    This study examines mucosa-specific regulatory pathways involved in modulation of interferon-gamma (IFN-gamma) in lamina propria T cells. Previous studies identified mucosa-specific CD2 cis-elements within the -204 to -108 bp IFNG promoter. Within this region, a single-site nucleotide polymorphism, -179G/T, imparts tumor necrosis factor-alpha stimulation of IFNG in peripheral blood lymphocytes, and is linked with accelerated AIDS progression. We discovered a putative estrogen response element (ERE) introduced by the -179T, which displays selective activation in peripheral blood mononuclear cells (PBMC) vs lamina propria mononuclear cells (LPMC). Transfection of PBMC with constructs containing the -179G or -179T site revealed CD2-mediated enhancement of the -179T compared to -179G allele, although, in LPMC, a similar level of expression was detected. Electrophoretic mobility shift assay (EMSA) analysis demonstrated CD2-mediated nucleoprotein binding to the -179T but not the -179G in PBMC. In LPMC, binding is constitutive to both -179G and -179T regions. Sequence and EMSA analysis suggests that the -179T allele creates an ERE-like binding site capable of binding recombinant estrogen receptor. Estrogen response element transactivation is enhanced by CD2 signaling, but inhibited by estrogen in PBMC but not in LPMC, although expression of estrogen receptor was similar. This is the first report to describe a potential molecular mechanism responsible for selectively controlling IFN-gamma production in LPMC.

  6. Co-expression of GAD67 and choline acetyltransferase in neurons in the mouse spinal cord: A focus on lamina X.

    Science.gov (United States)

    Gotts, Jittima; Atkinson, Lucy; Yanagawa, Yuchio; Deuchars, Jim; Deuchars, Susan A

    2016-09-01

    Lamina X of the spinal cord is a functionally diverse area with roles in locomotion, autonomic control and processing of mechano and nociceptive information. It is also a neurochemically diverse region. However, the different populations of cells in lamina X remain to be fully characterised. To determine the co-localisation of the enzymes responsible for the production of GABA and acetylcholine (which play major roles in the spinal cord) in lamina X of the adult and juvenile mouse, we used a transgenic mouse expressing green fluorescent protein (GFP) in glutamate decarboxylase 67 (GAD67) neurons, combined with choline acetyltransferase (ChAT) immunohistochemistry. ChAT-immunoreactive (IR) and GAD67-GFP containing neurons were observed in lamina X of both adult and juvenile mice and in both age groups a population of cells containing both ChAT-IR and GAD67-GFP were observed in lumbar, thoracic and cervical spinal cord. Such dual labelled cells were predominantly located ventral to the central canal. Immunohistochemistry for vesicular acetylcholine transporter (VAChT) and GAD67 revealed a small number of double labelled terminals located lateral, dorsolateral and ventrolateral to the central canal. This study therefore describes in detail a population of ChAT-IR/GAD67-GFP neurons predominantly ventral to the central canal of the cervical, thoracic and lumbar spinal cord of adult and juvenile mice. These cells potentially correspond to a sub-population of the cholinergic central canal cluster cells which may play a unique role in controlling spinal cord circuitry. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  7. Size dependence of ozone lamina characteristics and their correlations

    Czech Academy of Sciences Publication Activity Database

    Križan, Peter; Laštovička, Jan; Kozubek, Michal

    2015-01-01

    Roč. 132, September (2015), s. 116-123 ISSN 1364-6826 R&D Projects: GA ČR GA15-03909S Institutional support: RVO:68378289 Keywords : ozone laminae * correlations among laminae * vertical resolution of ozone sonde measurements Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.463, year: 2015 http://www.sciencedirect.com/science/article/pii/S1364682615300055

  8. Remodeling of the Nuclear Envelope and Lamina during Bovine Preimplantation Development and Its Functional Implications.

    Directory of Open Access Journals (Sweden)

    Jens Popken

    Full Text Available The present study demonstrates a major remodeling of the nuclear envelope and its underlying lamina during bovine preimplantation development. Up to the onset of major embryonic genome activation (MGA at the 8-cell stage nuclei showed a non-uniform distribution of nuclear pore complexes (NPCs. NPCs were exclusively present at sites where DNA contacted the nuclear lamina. Extended regions of the lamina, which were not contacted by DNA, lacked NPCs. In post-MGA nuclei the whole lamina was contacted rather uniformly by DNA. Accordingly, NPCs became uniformly distributed throughout the entire nuclear envelope. These findings shed new light on the conditions which control the integration of NPCs into the nuclear envelope. The switch from maternal to embryonic production of mRNAs was accompanied by multiple invaginations covered with NPCs, which may serve the increased demands of mRNA export and protein import. Other invaginations, as well as interior nuclear segments and vesicles without contact to the nuclear envelope, were exclusively positive for lamin B. Since the abundance of these invaginations and vesicles increased in concert with a massive nuclear volume reduction, we suggest that they reflect a mechanism for fitting the nuclear envelope and its lamina to a shrinking nuclear size during bovine preimplantation development. In addition, a deposit of extranuclear clusters of NUP153 (a marker for NPCs without associated lamin B was frequently observed from the zygote stage up to MGA. Corresponding RNA-Seq data revealed deposits of spliced, maternally provided NUP153 mRNA and little unspliced, newly synthesized RNA prior to MGA, which increased strongly at the initiation of embryonic expression of NUP153 at MGA.

  9. Radiologic study on lamina dura

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Hyung Kyu [Dept. of Radiology, College of Dentistry, Seoul National University, Seoul (Korea, Republic of)

    1981-11-15

    This study was performed to investigate the thickness of lamina dura of the human teeth in periodontal disease, which obtained from the intraoral roentgenograms of the 122 cases taken by bisecting technic. All films were divided into the different ages, the different sexes, and the different location of the different teeth. The obtained results were as follows: 1. Compared with the normal teeth, the thickness of lamina dura in periodontal disease is increased in all of different ages, sexes and teeth. 2. Generally, the alveolar crest portion is the thickest among the root surfaces, and midroot, apex followed, and the average thickness of the posterior teeth is thicker than that of anterior teeth. 3. The mean value of the whole maxillary teeth is almost same as that of mandibular teeth. 4. On the whole cases, the differences of male and female is about 0.01 mm, which is not a significant differences.

  10. Radiologic study on lamina dura

    International Nuclear Information System (INIS)

    Ahn, Hyung Kyu

    1981-01-01

    This study was performed to investigate the thickness of lamina dura of the human teeth in periodontal disease, which obtained from the intraoral roentgenograms of the 122 cases taken by bisecting technic. All films were divided into the different ages, the different sexes, and the different location of the different teeth. The obtained results were as follows: 1. Compared with the normal teeth, the thickness of lamina dura in periodontal disease is increased in all of different ages, sexes and teeth. 2. Generally, the alveolar crest portion is the thickest among the root surfaces, and midroot, apex followed, and the average thickness of the posterior teeth is thicker than that of anterior teeth. 3. The mean value of the whole maxillary teeth is almost same as that of mandibular teeth. 4. On the whole cases, the differences of male and female is about 0.01 mm, which is not a significant differences.

  11. CD4+ T regulatory cells from the colonic lamina propria of normal mice inhibit proliferation of enterobacteria-reactive, disease-inducing Th1-cells from scid mice with colitis

    DEFF Research Database (Denmark)

    Gad, M; Brimnes, J; Claesson, Mogens Helweg

    2003-01-01

    Adoptive transfer of CD4+ T cells into scid mice leads to a chronic colitis in the recipients. The transferred CD4+ T cells accumulate in the intestinal lamina propria (LP), express an activated Th1 phenotype and proliferate vigorously when exposed ex vivo to enteric bacterial antigens. As LP CD4......+ T cells from normal BALB/c mice do not respond to enteric bacterial antigens, we have investigated whether colonic LP-derived CD4+ T cells from normal mice suppress the antibacterial response of CD4+ T cells from scid mice with colitis. LP-derived CD4+ T cells cocultured with bone marrow......-derived dendritic cells effectively suppress the antibacterial proliferative response of CD4+ T cells from scid mice with colitis. The majority of these LP T-reg cells display a nonactivated phenotype and suppression is independent of antigen exposure, is partly mediated by soluble factor(s) different from IL-10...

  12. The diagnostic value of the alveolar lamina dura in generalised bone disease

    International Nuclear Information System (INIS)

    Kuhlencordt, J.; Kruse, H.P.; Franke, J.; Hamburg Univ.

    1981-01-01

    Changes in the alveolar lamina dura in 134 patients have been analysed. They included 32 cases with urolithiasis in whom generalised bone disease had been excluded, 37 cases of primary hyperparathyroidism, 31 cases of secondary hyperparathyroidism and 34 cases with primary osteoporosis. The state of the lamina dura was related to biochemical, radiological and histological findings in the various groups. The value of the lamina dura in the diagnosis of generalised skeletal abnormalities has been defined. (orig.) [de

  13. Toughening MoSi2 with Niobium metal -- Effects of size and orientation of ductile laminae

    International Nuclear Information System (INIS)

    Shaw, L.; Abbaschian, R.

    1994-01-01

    Effects of size and orientation of ductile laminae on the toughness of brittle matrix composites have been evaluated using MoSi 2 composites reinforced with Nb laminae. Nb laminae with thicknesses ranging from 0.127 to 1.0 mm were hot pressed with MoSi 2 powder to prepare the composites. Toughness of the composites was measured using four-point bend test on chevron-notched specimens. It was found that the toughness of the composites increased with increasing size of the niobium laminae. Furthermore, toughening was observed at crack propagation directions perpendicular to the laminae plane, indicating that ductile laminae offer two dimensional toughening. A model based on the bridging contribution of the ductile phase has been proposed to analyze the chevron-notched specimens of the ductile-phase-reinforced brittle matrix composites. The analysis showed that the dependence of the toughness of the composites on the size and orientation of the ductile laminae could be interpreted in terms of their bridging capability and bending contributions

  14. Contributions of the 12 neuron classes in the fly lamina to motion vision.

    Science.gov (United States)

    Tuthill, John C; Nern, Aljoscha; Holtz, Stephen L; Rubin, Gerald M; Reiser, Michael B

    2013-07-10

    Motion detection is a fundamental neural computation performed by many sensory systems. In the fly, local motion computation is thought to occur within the first two layers of the visual system, the lamina and medulla. We constructed specific genetic driver lines for each of the 12 neuron classes in the lamina. We then depolarized and hyperpolarized each neuron type and quantified fly behavioral responses to a diverse set of motion stimuli. We found that only a small number of lamina output neurons are essential for motion detection, while most neurons serve to sculpt and enhance these feedforward pathways. Two classes of feedback neurons (C2 and C3), and lamina output neurons (L2 and L4), are required for normal detection of directional motion stimuli. Our results reveal a prominent role for feedback and lateral interactions in motion processing and demonstrate that motion-dependent behaviors rely on contributions from nearly all lamina neuron classes. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Flow through internal elastic lamina affects shear stress on smooth muscle cells (3D simulations).

    Science.gov (United States)

    Tada, Shigeru; Tarbell, John M

    2002-02-01

    We describe a three-dimensional numerical simulation of interstitial flow through the medial layer of an artery accounting for the complex entrance condition associated with fenestral pores in the internal elastic lamina (IEL) to investigate the fluid mechanical environment around the smooth muscle cells (SMCs) right beneath the IEL. The IEL was modeled as an impermeable barrier to water flow except for the fenestral pores, which were assumed to be uniformly distributed over the IEL. The medial layer was modeled as a heterogeneous medium composed of a periodic array of cylindrical SMCs embedded in a continuous porous medium representing the interstitial proteoglycan and collagen matrix. Depending on the distance between the IEL bottom surface and the upstream end of the proximal layer of SMCs, the local shear stress on SMCs right beneath the fenestral pore could be more than 10 times higher than that on the cells far removed from the IEL under the conditions that the fenestral pore diameter and area fraction of pores were kept constant at 1.4 microm and 0.05, respectively. Thus these proximal SMCs may experience shear stress levels that are even higher than endothelial cells exposed to normal blood flow (order of 10 dyn/cm(2)). Furthermore, entrance flow through fenestral pores alters considerably the interstitial flow field in the medial layer over a spatial length scale of the order of the fenestral pore diameter. Thus the spatial gradient of shear stress on the most superficial SMC is noticeably higher than computed for endothelial cell surfaces.

  16. Characterization of the surface and interfacial properties of the lamina splendens

    Science.gov (United States)

    Rexwinkle, Joe T.; Hunt, Heather K.; Pfeiffer, Ferris M.

    2017-06-01

    Joint disease affects approximately 52.5 million patients in the United States alone, costing 80.8 billion USD in direct healthcare costs. The development of treatment programs for joint disease and trauma requires accurate assessment of articular cartilage degradation. The articular cartilage is the interfacial tissue between articulating surfaces, such as bones, and acts as low-friction interfaces. Damage to the lamina splendens, which is the articular cartilage's topmost layer, is an early indicator of joint degradation caused by injury or disease. By gaining comprehensive knowledge on the lamina splendens, particularly its structure and interfacial properties, researchers could enhance the accuracy of human and animal biomechanical models, as well as develop appropriate biomimetic materials for replacing damaged articular cartilage, thereby leading to rational treatment programs for joint disease and injury. Previous studies that utilize light, electron, and force microscopy techniques have found that the lamina splendens is composed of collagen fibers oriented parallel to the cartilage surface and encased in a proteoglycan matrix. Such orientation maximizes wear resistance and proteoglycan retention while promoting the passage of nutrients and synovial fluid. Although the structure of the lamina splendens has been explored in the literature, the low-friction interface of this tissue remains only partially characterized. Various functional models are currently available for the interface, such as pure boundary lubrication, thin films exuded under pressure, and sheets of trapped proteins. Recent studies suggest that each of these lubrication models has certain advantages over one another. Further research is needed to fully model the interface of this tissue. In this review, we summarize the methods for characterizing the lamina splendens and the results of each method. This paper aims to serve as a resource for existing studies to date and a roadmap of the

  17. Medial depression with bony dehiscence of lamina papyracea as an anatomic variation: CT evaluation

    International Nuclear Information System (INIS)

    Na, Sun Young; Lee, Young Uk; Youn, Eun Kyung; Suh, Sang Gyung; Kim, Dong Hyun

    1994-01-01

    To evaluate the incidence and CT findings of the medial depression and bony dehiscence of lamina papyracea as an anatomic variation. 1472 PNS CTs of the patients with symptoms of chronic sinusitis were retrospectively evaluated. The total incidence of depressed lamina papyracea as an anatomic variation was 3.5%(52/1472) on PNS CT. There was a statistically significant correlation between the increasing age and the incidence of depressed lamina papyracea. Depression of lamina papyracea anterior to the basal lamella were more common than those of the posterior depression. Associated findings were herniation of adjacent fatty tissue in all cases and the medial bowing and hypertrophied configuration of the medial rectus muscle without significant herniation in 19 cases(34%). Nontraumatic, asymptomatic depression with bony dehiscence of lamina papyracea as an anatomic variation is not uncommon with the incidence of 3.5%. Recognition of its existence and degree may be helpful in avoiding various ocular complication during ethmoid surgery

  18. Conditioned medium from LS 174T goblet cells treated with oxyresveratrol strengthens tight junctions in Caco-2 cells.

    Science.gov (United States)

    Hwang, Dahyun; Jo, HyunA; Hwang, Seonwook; Kim, Jeong-Keun; Kim, In-Ho; Lim, Young-Hee

    2017-01-01

    Strengthening of intestinal tight junctions provides an effective barrier from the external environment. Goblet cell-derived trefoil factor 3 (TFF3) increases transepithelial resistance by upregulating the expression of tight junction proteins. Oxyresveratrol (OXY) is a hydroxyl-substituted stilbene found in the roots, leaves, stems, and fruit of many plants and known to have various biological activities. In this study, we investigated the strengthening effect of OXY on intestinal tight junctions through stimulation of TFF production in goblet cells. We prepared conditioned medium from LS 174T goblet cells treated with OXY (GCO-CM) and investigated the effect of GCO-CM on strengthening tight junctions of Caco-2 cells. The mRNA and protein expression levels of major tight junction components (claudin-1, occludin, and ZO-1) were measured by quantitative real-time PCR and western blotting, respectively. Transepithelial electric resistance (TEER) was measured using an ohm/V meter. Monolayer permeability was evaluated by paracellular transport of fluorescein isothiocyanate-dextran. OXY showed a strong antioxidant activity. It significantly increased the expression level of TFF3 in LS 174T goblet cells. GCO-CM prepared by treatment with 2.5, 5, and 10μg/ml OXY did not show cytotoxicity in Caco-2 cells. GCO-CM increased the mRNA and protein expression levels of claudin-1, occludin, and ZO-1. It also significantly increased tight junction integrity and reduced permeability in a dose-dependent manner. OXY stimulates the expression of TFF3 in goblet cells, which might increase the integrity of the intestinal tight junction barrier. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  19. Discrimination of cortical laminae using MEG.

    Science.gov (United States)

    Troebinger, Luzia; López, José David; Lutti, Antoine; Bestmann, Sven; Barnes, Gareth

    2014-11-15

    Typically MEG source reconstruction is used to estimate the distribution of current flow on a single anatomically derived cortical surface model. In this study we use two such models representing superficial and deep cortical laminae. We establish how well we can discriminate between these two different cortical layer models based on the same MEG data in the presence of different levels of co-registration noise, Signal-to-Noise Ratio (SNR) and cortical patch size. We demonstrate that it is possible to make a distinction between superficial and deep cortical laminae for levels of co-registration noise of less than 2mm translation and 2° rotation at SNR > 11 dB. We also show that an incorrect estimate of cortical patch size will tend to bias layer estimates. We then use a 3D printed head-cast (Troebinger et al., 2014) to achieve comparable levels of co-registration noise, in an auditory evoked response paradigm, and show that it is possible to discriminate between these cortical layer models in real data. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  20. Glymphatic stasis at the site of the lamina cribrosa as a potential mechanism underlying open-angle glaucoma.

    Science.gov (United States)

    Wostyn, Peter; Killer, Hanspeter Esriel; De Deyn, Peter Paul

    2017-07-01

    The underlying pathophysiology of primary open-angle glaucoma remains unclear, but the lamina cribrosa seems to be the primary site of injury, and raised intraocular pressure is a major risk factor. In recent years, a decreased intracranial pressure, leading to an abnormally high trans-lamina cribrosa pressure difference, has gained interest as a new risk factor for glaucoma. New research now lends support to the hypothesis that a paravascular transport system is present in the eye analogous to the recently discovered 'glymphatic system' in the brain, which is a functional waste clearance pathway that promotes elimination of interstitial solutes, including β-amyloid, from the brain along paravascular channels. Given that β-amyloid has been reported to increase by chronic elevation of intraocular pressure in glaucomatous animal models and to cause retinal ganglion cell death, the discovery of a paravascular clearance system in the eye may provide powerful new insights into the pathophysiology of primary open-angle glaucoma. In this review, we provide a new conceptual framework for understanding the pathogenesis of primary open-angle glaucoma, present supporting preliminary data from our own post-mortem study and hypothesize that the disease may result from restriction of normal glymphatic flow at the level of the lamina cribrosa owing to a low intracranial pressure and/or a high trans-lamina cribrosa pressure gradient. If confirmed, this viewpoint could offer new perspectives for the development of novel diagnostic and therapeutic strategies for this devastating disorder. © 2017 Royal Australian and New Zealand College of Ophthalmologists.

  1. Nomenclature of Vertebral Laminae in Lizards, with Comments on Ontogenetic and Serial Variation in Lacertini (Squamata, Lacertidae).

    Science.gov (United States)

    Tschopp, Emanuel

    2016-01-01

    Vertebral laminae are bony ridges or sheets that connect important morphological landmarks on the vertebrae, like diapophyses or zygapophyses. They usually exhibit some serial variation throughout the column. A consistent terminology facilitates the morphological description of this variation, and the recognition of patterns that could be taxonomically significant and could serve as phylogenetic characters. Such a terminology was designed for saurischian dinosaurs, and has also been applied to other members of Archosauriformes. Herein, this terminology is applied for the first time to lizards (Squamata). Probably due to their generally smaller size compared to saurischian dinosaurs, lizards have less developed vertebral laminae. Some laminae could not be recognized in this group and others require new names to account for differences in basic vertebral morphology. For instance, the fusion of diapophysis and parapophysis in lacertids into a structure called synapophysis necessitates the creation of the new term synapophyseal laminae for both diapophyseal and parapophyseal laminae. An assessment of occurrence and serial variation in a number of lacertid species shows that some laminae develop throughout ontogeny or only occur in large-sized species, whereas the distribution of other laminae might prove to be taxonomically significant in future.

  2. Nomenclature of Vertebral Laminae in Lizards, with Comments on Ontogenetic and Serial Variation in Lacertini (Squamata, Lacertidae.

    Directory of Open Access Journals (Sweden)

    Emanuel Tschopp

    Full Text Available Vertebral laminae are bony ridges or sheets that connect important morphological landmarks on the vertebrae, like diapophyses or zygapophyses. They usually exhibit some serial variation throughout the column. A consistent terminology facilitates the morphological description of this variation, and the recognition of patterns that could be taxonomically significant and could serve as phylogenetic characters. Such a terminology was designed for saurischian dinosaurs, and has also been applied to other members of Archosauriformes. Herein, this terminology is applied for the first time to lizards (Squamata. Probably due to their generally smaller size compared to saurischian dinosaurs, lizards have less developed vertebral laminae. Some laminae could not be recognized in this group and others require new names to account for differences in basic vertebral morphology. For instance, the fusion of diapophysis and parapophysis in lacertids into a structure called synapophysis necessitates the creation of the new term synapophyseal laminae for both diapophyseal and parapophyseal laminae. An assessment of occurrence and serial variation in a number of lacertid species shows that some laminae develop throughout ontogeny or only occur in large-sized species, whereas the distribution of other laminae might prove to be taxonomically significant in future.

  3. Mechanisms and timing of replacement dental lamina regression

    Czech Academy of Sciences Publication Activity Database

    Dosedělová, H.; Dumková, J.; Lesot, H.; Glocová, K.; Hampl, A.; Tucker, A.; Buchtová, Marcela

    2013-01-01

    Roč. 296, special feature (2013), s. 272-272 ISSN 1932-8486. [International Congress of Vertebrate Morphology /10./. 08.07.2013-12.07.2013, Barcelona] Institutional support: RVO:67985904 Keywords : dental lamina Subject RIV: FF - HEENT, Dentistry

  4. Compartmentalised expression of meprin in small intestinal mucosa: enhanced expression in lamina propria in coeliac disease.

    Science.gov (United States)

    Lottaz, Daniel; Buri, Caroline; Monteleone, Giovanni; Rösmann, Sandra; Macdonald, Thomas T; Sanderson, Ian R; Sterchi, Erwin E

    2007-03-01

    Epithelial cells in the human small intestine express meprin, an astacin-like metalloprotease, which accumulates normally at the brush border membrane and in the gut lumen. Therefore, meprin is targeted towards luminal components. In coeliac disease patients, peptides from ingested cereals trigger mucosal inflammation in the small intestine, disrupting epithelial cell differentiation and function. Using in situ hybridisation on duodenal tissue sections, we observed a marked shift of meprin mRNA expression from epithelial cells, the predominant expression site in normal mucosa, to lamina propria leukocytes in coeliac disease. Meprin thereby gains access to the substrate repertoire present beneath the epithelium.

  5. Experimental analysis of compressive notch strengthening in closed-cell aluminum alloy foam

    NARCIS (Netherlands)

    Antoniou, A; Onck, PR; Bastawros, Ashraf F.

    2004-01-01

    The notch strengthening effect is studied experimentally in closed cell aluminum foams. The limit loads, net section strength were found for a set of double-edge-notched (DEN) and single-edge-notched (SEN) specimens loaded in compression. In addition, the evolution of the deformation is monitored

  6. The Insulator Protein SU(HW) Fine-Tunes Nuclear Lamina Interactions of the Drosophila Genome

    NARCIS (Netherlands)

    Van Bemmel, J.G.; Pagie, L.; Braunschweig, U.; Brugman, W.; Meuleman, W.; Kerkhoven, R.M.; Van Steensel, B.

    2010-01-01

    Specific interactions of the genome with the nuclear lamina (NL) are thought to assist chromosome folding inside the nucleus and to contribute to the regulation of gene expression. High-resolution mapping has recently identified hundreds of large, sharply defined lamina-associated domains (LADs) in

  7. The formation process of the flood type lamina in the Lake Mokoto, Hokkaido, Japan.

    Science.gov (United States)

    Seto, K.; Katsuki, K.; Takeshi, S.

    2017-12-01

    In the coastal area of the Sea of Okhotsk in the east part of Hokkaido located to subarctic zone, many brackish-water lakes are distributed. Lake Mokoto consist of organic mud with the lamination. The 09Mk-1C core at 2009. In the soft X-ray photograph, the cyclic lamina set is observed. The cyclic lamina set consists of low- and high-density lamina. According to the meteorological data in Abashiri region, the annually precipitation is high from August to September. Probably, the cyclic lamina set is formed by seasonal change of precipitation. In August 2016, it showed a precipitation of 425 mm which is about 4 times the average precipitation. In February 2017, the 10 cm class short core (17Mk-4SC core) was collected and the flood lamina was observed. Six layers showing different color were observed in top 6.5 cm. The first, third and fifth layers from the top are relatively light in color (L*value=17). The second, fourth and sixth layers are relatively dark in color (L*value=8). Thickness of the first to fourth layers is about 5 mm, but the thickness of the fifth layer reaches 4 cm. According to the observation of the soft X-ray photograph, the third and fifth layers were high-density lamina, and the others were low-density lamina. Because these layers were not observed in the 15Mk-3C core collected in March 2015, they were deposited after that. It is estimated that the third layer showing the high-density lamina is the sediment of the flood event in August 2016. This is supported by the fact that the total organic carbon (TOC) and total sulfur (TS) contents are diluted and the C/N ratio is relatively high value. Because this lamina is remarkable, it will be used as a future key bed. On the other hand, the fifth layer showing the high-density is a very thick. In this layer, the TS content is diluted and the C/N ratio is high, but the TOC content shows the highest value. This suggests that sediments with high TOC content flowed out from Mokoto River Basin. It has

  8. Brilliant iridescence of Morpho butterfly wing scales is due to both a thin film lower lamina and a multilayered upper lamina.

    Science.gov (United States)

    Giraldo, M A; Stavenga, D G

    2016-05-01

    Butterflies belonging to the nymphalid subfamily, Morphinae, are famous for their brilliant blue wing coloration and iridescence. These striking optical phenomena are commonly explained as to originate from multilayer reflections by the ridges of the wing scales. Because the lower lamina of the scales of related nymphalid butterflies, the Nymphalinae, plays a dominant role in the wing coloration, by acting as a thin film reflector, we investigated single blue scales of three characteristic Morpho species: M. epistrophus, M. helenor and M. cypris. The experimental data obtained by spectrophotometry, scatterometry and scanning electron microscopy demonstrated that also in the Morpho genus the lower lamina of both the cover and ground scales acts as an optical thin film reflector, contributing importantly to the blue structural coloration of the wings. Melanin pigment has a contrast-enhancing function in a sub-class of ground scales.

  9. CXCL14-like Immunoreactivity Exists in Somatostatin-containing Endocrine Cells, and in the Lamina Propria and Submucosal Somatostatinergic Nervous System of Mouse Alimentary Tract.

    Science.gov (United States)

    Suzuki, Hirohumi; Yamada, Kentaro; Matsuda, Yasuhiro; Onozuka, Minoru; Yamamoto, Toshiharu

    2017-12-26

    In the present study, we investigated the distribution of CXCL14 immunoreactive endocrine cells and neurons in mouse alimentary tract by immunohistochemistry. CXCL14 immunoreactive endocrine cells were found as closed-type cells in the stomach and open-type cells in the small intestine. The immunostaining of these endocrine cells corresponded with that of the somatostatin-containing endocrine cells. Only a few CXCL14 immunoreactive endocrine cells were seen in the large intestine. CXCL14 immunoreactive fibers were observed in the muscular layer from the stomach to the rectum with most abundance in the rectum. Many CXCL14 immunoreactive fibers were observed in the lamina propria and submucosal layer from the duodenum to the rectum with most abundance in the rectum; these fibers corresponded to the somatostatin-containing nerve fibers. Some CXCL14 immunoreactive neuronal somata that were also immuno-positive for somatostatin, were noted in the submucosal layer of the rectum. However, the remaining parts of the alimentary tract presented with almost negligible immunoreactive somata. The co-localization of CXCL14 and somatostatin suggests that CXCL14 contributes to the function of somatostatin, which include the inhibition of other endocrine and exocrine cells and the enteric nervous systems.

  10. Brilliant iridescence of Morpho butterfly wing scales is due to both a thin film lower lamina and a multilayered upper lamina

    NARCIS (Netherlands)

    Giraldo, M A; Stavenga, D G

    2016-01-01

    Butterflies belonging to the nymphalid subfamily, Morphinae, are famous for their brilliant blue wing coloration and iridescence. These striking optical phenomena are commonly explained as to originate from multilayer reflections by the ridges of the wing scales. Because the lower lamina of the

  11. Experimental Investigations on the effect of Additive on the Tensile Properties of Fiber Glass Fabric Lamina

    Science.gov (United States)

    Nava Sai Divya, A.; Raghu Kumar, B., Dr; Lakshmi Narayana, G., Dr

    2017-09-01

    The main objective of this work is to investigate the effect of additives on tensile behaviour of fiber glass fabric at lamina level to explore an alternative skin material for the outer body of aerospace applications and machines. This experimental work investigates the effect of silica concentration in epoxy resin lapox L-12 on the tensile properties of glass fabric lamina of 4H-satin weave having 3.6 mm thickness. The lamina was prepared by using hand lay-up method and tests were conducted on it. Various tensile properties values obtained from experimentation were compared for four glass fiber lamina composites fabricated by adding the silica powder to resin bath. The effect of variations in silica concentration (0% SiO2, 5% SiO2, 10% SiO2 and 15% SiO2) on the tensile properties of prepared material revealed that maximum stiffness was obtained at 15% and yield strength at 10% SiO2 concentration in glass fiber lamina. Increasing the silica concentration beyond 10% had led to deterioration in the material properties. The experimentation that was carried out on test specimen was reasonably successful as the effect of silica powder as an additive in glass fiber lamina enhanced the mechanical properties up to certain limit. The underpinning microscopic behaviour at the source of these observations will be investigated in a follow up work.

  12. The influence of the level of lamina propria invasion and the prevalence of p53 nuclear accumulation on survival in stage T1 transitional cell bladder cancer

    DEFF Research Database (Denmark)

    Hermann, G G; Horn, T; Steven, K

    1998-01-01

    and routinely grouped according to the level of lamina propria invasion. Invasion of the tumor stalk was defined as stage T1a, invasion of the lamina propria proper superficial to the level of muscularis mucosa as stage T1b and into or deeper than the muscularis mucosa as stage T1c. The p53 nuclear...

  13. Basal lamina structural alterations in human asymmetric aneurismatic aorta

    Directory of Open Access Journals (Sweden)

    M Cotrufo

    2009-06-01

    Full Text Available Basal lamina (BL is a crucial mechanical and functional component of blood vessels, constituting a sensor of extracellular microenvironment for endothelial cells and pericytes. Recently, an abnormality in the process of matrix microfibrillar component remodeling has been advocated as a mechanism involved in the development of aortic dilation.We focused our attention on BL composition and organization and studied some of the main components of the Extracellular Matrix such as Tenascin, Laminins, Fibronectin, type I, III and IV Collagens.We used surgical fragments from 27 patients, submitted to operation because of aortic root aneurysm and 5 normal aortic wall specimens from heart donors without any evidence for aneurysmal or atherosclerotic diseases of the aorta. Two samples of aortic wall were harvested from each patient, proximal to the sinotubular junction at the aortic convexity and concavity. Each specimen was processed both for immunohistochemical examination and molecular biology study.We compared the convexity of each aortic sample with the concavity of the same vessel, and both of them with the control samples. The synthesis of mRNA and the levels of each protein were assessed, respectively, by RTPCR and Western Blot analysis. Immunohistochemistry elucidated the organization of BL, whose composition was revealed by molecular biology. All pathological samples showed a wall thinner than normal ones. Basal lamina of the aortic wall evidentiated important changes in the tridimensional arrangement of its major components which lost their regular arrangement in pathological specimens. Collagen I, Laminin a2 chain and Fibronectin amounts decreased in pathological samples, while type IV Collagen and Tenascin synthesis increased. Consistently with the common macroscopic observation that ascending aorta dilations tend to expand asymmetrically, with prevalent involvement of the vessel convexity and relative sparing of the concavity, Collagen type

  14. Spatial distribution and functional significance of leaf lamina shape in Amazonian forest trees

    Directory of Open Access Journals (Sweden)

    A. C. M. Malhado

    2009-08-01

    Full Text Available Leaves in tropical forests come in an enormous variety of sizes and shapes, each of which can be ultimately viewed as an adaptation to the complex problem of optimising the capture of light for photosynthesis. However, the fact that many different shape "strategies" coexist within a habitat demonstrate that there are many other intrinsic and extrinsic factors involved, such as the differential investment in support tissues required for different leaf lamina shapes. Here, we take a macrogeographic approach to understanding the function of different lamina shape categories. Specifically, we use 106 permanent plots spread across the Amazon rainforest basin to: 1 describe the geographic distribution of some simple metrics of lamina shape in plots from across Amazonia, and; 2 identify and quantify relationships between key environmental parameters and lamina shape in tropical forests. Because the plots are not randomly distributed across the study area, achieving this latter objective requires the use of statistics that can account for spatial auto-correlation. We found that between 60–70% of the 2791 species and 83 908 individual trees in the dataset could be classified as having elliptic leaves (= the widest part of the leaf is on an axis in the middle fifth of the long axis of the leaf. Furthermore, the average Amazonian tree leaf is 2.5 times longer than it is wide and has an entire margin. Contrary to theoretical expectations we found little support for the hypothesis that narrow leaves are an adaptation to dry conditions. However, we did find strong regional patterns in leaf lamina length-width ratios and several significant correlations with precipitation variables suggesting that water availability may be exerting an as yet unrecognised selective pressure on leaf shape of rainforest trees. Some support was found for the hypothesis that narrow leaves are an adaptation to low nutrient soils. Furthermore, we found a strong correlation between

  15. The insulator protein SU(HW fine-tunes nuclear lamina interactions of the Drosophila genome.

    Directory of Open Access Journals (Sweden)

    Joke G van Bemmel

    Full Text Available Specific interactions of the genome with the nuclear lamina (NL are thought to assist chromosome folding inside the nucleus and to contribute to the regulation of gene expression. High-resolution mapping has recently identified hundreds of large, sharply defined lamina-associated domains (LADs in the human genome, and suggested that the insulator protein CTCF may help to demarcate these domains. Here, we report the detailed structure of LADs in Drosophila cells, and investigate the putative roles of five insulator proteins in LAD organization. We found that the Drosophila genome is also organized in discrete LADs, which are about five times smaller than human LADs but contain on average a similar number of genes. Systematic comparison to new and published insulator binding maps shows that only SU(HW binds preferentially at LAD borders and at specific positions inside LADs, while GAF, CTCF, BEAF-32 and DWG are mostly absent from these regions. By knockdown and overexpression studies we demonstrate that SU(HW weakens genome - NL interactions through a local antagonistic effect, but we did not obtain evidence that it is essential for border formation. Our results provide insights into the evolution of LAD organization and identify SU(HW as a fine-tuner of genome - NL interactions.

  16. Diagenetic variation at the lamina scale in lacustrine organic-rich shales: Implications for hydrocarbon migration and accumulation

    Science.gov (United States)

    Liang, Chao; Cao, Yingchang; Liu, Keyu; Jiang, Zaixing; Wu, Jing; Hao, Fang

    2018-05-01

    Lacustrine carbonate-rich shales are well developed within the Mesozoic-Cenozoic strata of the Bohai Bay Basin (BBB) of eastern China and across southeast Asia. Developing an understanding of the diagenesis of these shales is essential to research on mass balance, diagenetic fluid transport and exchange, and organic-inorganic interactions in black shales. This study investigates the origin and distribution of authigenic minerals and their diagenetic characteristics, processes, and pathways at the scale of lacustrine laminae within the Es4s-Es3x shale sequence of the BBB. The research presented in this study is based on thin sections, field emission scanning electron microscope (FESEM) and SEM-catholuminescence (CL) observations of well core samples combined with the use of X-ray diffraction (XRD), energy dispersive spectroscopy, electron microprobe analysis, and carbon and oxygen isotope analyses performed using a laser microprobe mass spectrometer. The dominant lithofacies within the Es4s-Es3x sequence are a laminated calcareous shale (LCS-1) and a laminated clay shale (LCS-2). The results of this study show that calcite recrystallization1 is the overarching diagenetic process affecting the LCS-1, related to acid generation from organic matter (OM) thermal evolution. This evolutionary transition is the key factor driving the diagenesis of this lithofacies, while the transformation of clay minerals is the main diagenetic attribute of the LCS-2. Diagenetic differences occur within different laminae and at variable locations within the same lamina level, controlled by variations in mineral composition and the properties of laminae interfaces. The diagenetic fluid migration scale is vertical and responses (dissolution and replacement) are limited to individual laminae, between zero and 100 μm in width. In contrast, the dominant migration pathway for diagenetic fluid is lateral, along the abrupt interfaces between laminae boundaries, which leads to the vertical

  17. Casein kinase II protein kinase is bound to lamina-matrix and phosphorylates lamin-like protein in isolated pea nuclei

    Science.gov (United States)

    Li, H.; Roux, S. J.

    1992-01-01

    A casein kinase II (CK II)-like protein kinase was identified and partially isolated from a purified envelope-matrix fraction of pea (Pisum sativum L.) nuclei. When [gamma-32P]ATP was directly added to the envelope-matrix preparation, the three most heavily labeled protein bands had molecular masses near 71, 48, and 46 kDa. Protein kinases were removed from the preparation by sequential extraction with Triton X-100, EGTA, 0.3 M NaCl, and a pH 10.5 buffer, but an active kinase still remained bound to the remaining lamina-matrix fraction after these treatments. This kinase had properties resembling CK II kinases previously characterized from animal and plant sources: it preferred casein as an artificial substrate, could use GTP as efficiently as ATP as the phosphoryl donor, was stimulated by spermine, was calcium independent, and had a catalytic subunit of 36 kDa. Some animal and plant CK II kinases have regulatory subunits near 29 kDa, and a lamina-matrix-bound protein of this molecular mass was recognized on immunoblot by anti-Drosophila CK II polyclonal antibodies. Also found associated with the envelope-matrix fraction of pea nuclei were p34cdc2-like and Ca(2+)-dependent protein kinases, but their properties could not account for the protein kinase activity bound to the lamina. The 71-kDa substrate of the CK II-like kinase was lamin A-like, both in its molecular mass and in its cross-reactivity with anti-intermediate filament antibodies. Lamin phosphorylation is considered a crucial early step in the entry of cells into mitosis, so lamina-bound CK II kinases may be important control points for cellular proliferation.

  18. Estimation of Lamina Stiffness and Strength of Quadriaxial Non-Crimp Fabric Composites Based on Semi-Laminar Considerations

    Directory of Open Access Journals (Sweden)

    Yong Cao

    2016-09-01

    Full Text Available Quadriaxial non-crimp fabric (QNCF composites are increasingly being used as primary structural materials in aircraft and automotive applications. Predicting the mechanical properties of QNCF lamina is more complicated compared with that of unidirectional (UD composites, because of the knitting connection of different plies. In this study, to analyze the stiffness and strength of the QNCF composites, a novel modeling strategy for the meso-scale features is presented based on the semi-laminar assumption. Following the view of the mechanical properties of single composite lamina, the complex QNCF layer is decomposed into individual plies. Three different representative unit cells along fiber direction are selected to predict the mechanical performance of QNCF, including in-plane stiffness, damage initiation, and stiffness degradation. To validate the developed modeling strategy, the predictions are compared with existing experimental results, where a good agreement is presented on the prediction of in-plane stiffness and strength. Furthermore, the effect of in-plane fiber distortion, induced by the stitching yarn on the mechanical properties, is studied.

  19. Glymphatic stasis at the site of the lamina cribrosa as a potential mechanism underlying open-angle glaucoma

    NARCIS (Netherlands)

    Wostyn, Peter; Killer, Hanspeter Esriel; De Deyn, Peter Paul

    The underlying pathophysiology of primary open-angle glaucoma remains unclear, but the lamina cribrosa seems to be the primary site of injury, and raised intraocular pressure is a major risk factor. In recent years, a decreased intracranial pressure, leading to an abnormally high trans-lamina

  20. Microscopic Colitis Evolved Into Inflammatory Bowel Diseases Is Characterized by Increased Th1/Tc1 Cells in Colonic Mucosal Lamina Propria.

    Science.gov (United States)

    Li, Ji; Yan, Yuchu; Meng, Ziran; Liu, Shuhong; Beck, Paul L; Ghosh, Subrata; Qian, Jiaming; Gui, Xianyong

    2017-10-01

    An association between microscopic colitis (MC), i.e., lymphocytic colitis (LC) and collagenous colitis (CC), and inflammatory bowel diseases (IBD) has been noticed. A subset of MC cases may evolve into IBD, and IBD in remission may present as MC in a histologic pattern. Moreover, MC and IBD may coexist in different regions of the bowel. A link between MC and IBD in their pathogenesis is, therefore, suggested. Abnormal mucosal immunity is likely the key. We reviewed 2324 MC cases in Calgary over 14 years and identified 20 cases evolved into IBD (IBD transformers). 13 of them were further investigated for colonic mucosal lamina propria mononuclear cells (LPMNCs), as opposed to 22 cases whose MC resolved. On their index colonic biopsy immunohistochemistry was performed to detect major T cell subsets characterized by key cytokines and master transcription factors (IFNγ and T-bet for Th1/Tc1, GATA-3 for Th2/Tc2, IL-17 and RORc for Th17/Tc17, FoxP3 for Treg/Tcreg) as well as TNFα + cells (partly representing Th1). LPMNCs positive for each marker were counted (average number per high-power field). IBD transformers had increased IFNγ + , T-bet + , TNF-α + , and GATA-3 + LPMNCs compared to the MC-resolved cases. The LC-to-IBD subgroup had increased IFNγ + and GATA-3 + cells compared to the LC-resolved subgroup. The CC-to-IBD subgroup had increased T-bet + , TNF-α + , and GATA-3 + cells compared to the CC-resolved subgroup. Among MC-resolved patients, more TNF-α + and RORc + cells were seen in LC than in CC. Th1/Tc1- and TNFα-producing cells, and likely a subset of Th2/Tc2 cells as well, may be involved in the MC-to-IBD transformation.

  1. The essential oil in lamina and petiole of heracleum-dissectum leaves

    NARCIS (Netherlands)

    Montanarella, L; Bos, R; Fisher, FC

    The essential oils of lamina and petiole of Heracleum dissectum are described. Fifty-seven compounds have been identified by mass spectrometry and retention indices. Differences between the oils of the two organs were mainly quantitative.

  2. Regulatory role of NKG2D+ NK cells in intestinal lamina propria by secreting double-edged Th1 cytokines in ulcerative colitis.

    Science.gov (United States)

    Wang, Fan; Peng, Pai-Lan; Lin, Xue; Chang, Ying; Liu, Jing; Zhou, Rui; Nie, Jia-Yan; Dong, Wei-Guo; Zhao, Qiu; Li, Jin

    2017-11-17

    The role of intestinal lamina propria (LP) NKG2D+ NK cells is unclear in regulating Th1/Th2 balance in ulcerative colitis (UC). In this study, we investigated the frequency of LP NKG2D+ NK cells in DSS-induced colitis model and intestinal mucosal samples of UC patients, as well as the secretion of Th1/Th2/Th17 cytokines in NK cell lines after MICA stimulation. The role of Th1 cytokines in UC was validated by bioinformatics analysis. We found that DSS-induced colitis in mice was characterized by a Th2-mediated process. In acute phrase, the frequency of LP NKG2D+ lymphocytes increased significantly and decreased in remission, while the frequency of LP NKG2D+ NK cells decreased significantly in acute phase and increased in remission. No obvious change was found in the frequency of total LP NK cells. Similarly, severe UC patients had a higher expression of mucosal NKG2D and a lower number of NKG2D+ NK cells than mild to moderate UC. In NK cell lines, the MICA stimulation could induce a predominant secretion of Th1 cytokines (TNF, IFN-γ). Furthermore, in bioinformatics analysis, mucosal Th1 cytokine of TNF, showed a double-edged role in UC when compared to the Th1-mediated disease of Crohn's colitis. In conclusion, LP NKG2D+ NK cells partially played a regulatory role in UC through secreting Th1 cytokines to regulate the Th2-predominant Th1/Th2 imbalance, despite of the concomitant pro-inflammatory effects of Th1 cytokines.

  3. Basilar membrane and reticular lamina motion in a multi-scale finite element model of the mouse cochlea

    Science.gov (United States)

    Soons, Joris; Dirckx, Joris; Steele, Charles; Puria, Sunil

    2015-12-01

    A multi-scale finite element (FE) model of the mouse cochlea, based on its anatomy and material properties is presented. The important feature in the model is a lattice of 400 Y-shaped structures in the longitudinal direction, each formed by Deiters cells, phalangeal processes and outer hair cells (OHC). OHC somatic motility is modeled by an expansion force proportional to the shear on the stereocilia, which in turn is proportional to the pressure difference between the scala vestibule and scala tympani. Basilar membrane (BM) and reticular lamina (RL) velocity compare qualitatively very well with recent in vivo measurements in guinea pig [2]. Compared to the BM, the RL is shown to have higher amplification and a shift to higher frequencies. This comes naturally from the realistic Y-shaped cell organization without tectorial membrane tuning.

  4. Anterior lamina cribrosa surface position in idiopathic intracranial hypertension and glaucoma

    DEFF Research Database (Denmark)

    Villarruel, Jenni Martinez; Li, Xiao Q.; Bach-Holm, Daniella

    2017-01-01

    Purpose: To compare the anterior lamina cribrosa (LC) surface position in patients with idiopathic intracranial hypertension (IIH), primary open-angle glaucoma (high-tension glaucoma [HTG] and normal-tension glaucoma [NTG]), and healthy controls using enhanced depth imaging spectral-domain optical...

  5. Microbial Communities and Their Predicted Metabolic Functions in Growth Laminae of a Unique Large Conical Mat from Lake Untersee, East Antarctica

    Directory of Open Access Journals (Sweden)

    Hyunmin Koo

    2017-08-01

    Full Text Available In this study, we report the distribution of microbial taxa and their predicted metabolic functions observed in the top (U1, middle (U2, and inner (U3 decadal growth laminae of a unique large conical microbial mat from perennially ice-covered Lake Untersee of East Antarctica, using NextGen sequencing of the 16S rRNA gene and bioinformatics tools. The results showed that the U1 lamina was dominated by cyanobacteria, specifically Phormidium sp., Leptolyngbya sp., and Pseudanabaena sp. The U2 and U3 laminae had high abundances of Actinobacteria, Verrucomicrobia, Proteobacteria, and Bacteroidetes. Closely related taxa within each abundant bacterial taxon found in each lamina were further differentiated at the highest taxonomic resolution using the oligotyping method. PICRUSt analysis, which determines predicted KEGG functional categories from the gene contents and abundances among microbial communities, revealed a high number of sequences belonging to carbon fixation, energy metabolism, cyanophycin, chlorophyll, and photosynthesis proteins in the U1 lamina. The functional predictions of the microbial communities in U2 and U3 represented signal transduction, membrane transport, zinc transport and amino acid-, carbohydrate-, and arsenic- metabolisms. The Nearest Sequenced Taxon Index (NSTI values processed through PICRUSt were 0.10, 0.13, and 0.11 for U1, U2, and U3 laminae, respectively. These values indicated a close correspondence with the reference microbial genome database, implying high confidence in the predicted metabolic functions of the microbial communities in each lamina. The distribution of microbial taxa observed in each lamina and their predicted metabolic functions provides additional insight into the complex microbial ecosystem at Lake Untersee, and lays the foundation for studies that will enhance our understanding of the mechanisms responsible for the formation of these unique mat structures and their evolutionary significance.

  6. Effect of Lamina Thickness of Prepreg on the Surface Accuracy of Carbon Fiber Composite Space Mirrors

    Science.gov (United States)

    Yang, Zhiyong; Tang, Zhanwen; Xie, Yongjie; Shi, Hanqiao; Zhang, Boming; Guo, Hongjun

    2018-02-01

    Composite space mirror can completely replicate the high-precision surface of mould by replication process, but the actual surface accuracy of the replication composite mirror always decreases. Lamina thickness of prepreg affects the layers and layup sequence of composite space mirror, and which would affect surface accuracy of space mirror. In our research, two groups of contrasting cases through finite element analyses (FEA) and comparative experiments were studied; the effect of different lamina thicknesses of prepreg and corresponding lay-up sequences was focused as well. We describe a special analysis model, validated process and result analysis. The simulated and measured surface figures both get the same conclusion. Reducing lamina thickness of prepreg used in replicating composite space mirror is propitious to optimal design of layup sequence for fabricating composite mirror, and could improve its surface accuracy.

  7. Anterior lamina cribrosa insertion in primary open-angle glaucoma patients and healthy subjects.

    Directory of Open Access Journals (Sweden)

    Kyoung Min Lee

    Full Text Available To determine using swept-source optical coherence tomography (SS-OCT whether there are differences in the location of the anterior lamina cribrosa insertion (ALI in primary open-angle glaucoma (POAG patients and healthy subjects.Fifty three eyes from 53 patients with POAG, and 53 eyes from 53 age-matched healthy subjects were included prospectively in Seoul National University Bundang Hospital. Twelve radial line B-scans centered on the optic disc in every half-clock-hour meridian were acquired using SS-OCT. The ALI position was assessed by measuring two parameters: (1 ALI distance (ALID--the distance from the anterior scleral canal opening (ASCO to the ALI; and (2 marginal anterior lamina cribrosa surface depth (mALCSD--the perpendicular distance from the ASCO plane to the anterior lamina cribrosa surface. These parameters were compared between the two groups for each meridian.Both ALID (256 ± 54 vs. 209 ± 37 µm, mean ± SD, p < 0.001 and mALCSD (232 ± 63 vs. 187 ± 40 µm, p < 0.001 were significantly greater in the POAG group than in the normal group. The largest difference was observed at the 6.5 o'clock and 11.5 o'clock meridians for both ALID and mALCSD. Multiple regression analysis revealed a negative correlation between age and both ALID and mALCSD in the control group, and a negative correlation between mean deviation of the visual field test and both ALID and mALCSD in the POAG group.The ALI was displaced posteriorly in eyes with POAG compared to those of healthy controls. This finding suggests that the posteriorly located lamina cribrosa insertion is an important component of glaucomatous optic nerve excavation.

  8. Evaluation of the rostral projection of the sacral lamina as a component of degenerative lumbosacral stenosis in German shepherd dogs.

    Science.gov (United States)

    Saunders, Harvey; Worth, Andrew J; Bridges, Janis P; Hartman, Angela

    2018-05-20

    To determine the association between a greater rostral projection of the sacral lamina and clinical signs of cauda equina syndrome (CES) in German shepherd dogs (GSD) with presumptive degenerative lumbosacral disease (DLSS). Retrospective cohort study. One hundred forty-three GSD (125 police dogs and 18 pet dogs) presenting for either CES or prebreeding evaluation. Fifty-five were classified as affected by CES and diagnosed with DLSS, and 88 were classified as unaffected on the basis of clinical and imaging findings. The position of the rostral edge of the sacral lamina was measured from radiographs and/or computed tomography (CT) scans. This position was compared between affected and unaffected dogs. In dogs that underwent both radiography and CT scanning, the agreement between sacral lamina localization using each imaging modality was determined. Owners/handlers were contacted to determine whether dogs subsequently developed clinical signs compatible with CES at a mean of 29 months (unaffected). The sacral lamina did not extend as far rostrally in affected dogs, compared to unaffected dogs (P = .04). Among the 88 dogs unaffected by CES at initial evaluation, 2 developed clinical signs consistent with CES at follow-up. Rostral projection of the sacral lamina, previously proposed as a potential risk factor in dogs with CES due to lumbosacral degeneration, was not associated with a diagnosis of DLSS in this study; the opposite was true. Rostral projection of the sacral lamina may not be a predisposing factor in the development of CES due to DLSS in GSD. © 2018 The American College of Veterinary Surgeons.

  9. Single‑shot lamina technique of paravertebral block as an adjunct to ...

    African Journals Online (AJOL)

    Thoracic paravertebral block can be employed as an alternative or an adjunct to general anesthesia (GA) for breast cancer surgery. There is no report of this new lamina technique for catheter placement in our environment. In low‑resource settings, potent opioids are lacking and the extended postoperative analgesia it ...

  10. Identification of putative dental epithelial stem cells in a lizard with life-long tooth replacement.

    Science.gov (United States)

    Handrigan, Gregory R; Leung, Kelvin J; Richman, Joy M

    2010-11-01

    Most dentate vertebrates, including humans, replace their teeth and yet the process is poorly understood. Here, we investigate whether dental epithelial stem cells exist in a polyphyodont species, the leopard gecko (Eublepharis macularius). Since the gecko dental epithelium lacks a histologically distinct site for stem cells analogous to the mammalian hair follicle bulge, we performed a pulse-chase experiment on juvenile geckos to identify label-retaining cells (LRCs). We detected LRCs exclusively on the lingual side of the dental lamina, which exhibits low proliferation rates and is not involved in tooth morphogenesis. Lingual LRCs were organized into pockets of high density close to the successional lamina. A subset of the LRCs expresses Lgr5 and other genes that are markers of adult stem cells in mammals. Also similar to mammalian stem cells, the LRCs appear to proliferate in response to gain of function of the canonical Wnt pathway. We suggest that the LRCs in the lingual dental lamina represent a population of stem cells, the immediate descendents of which form the successional lamina and, ultimately, the replacement teeth in the gecko. Furthermore, their location on the non-tooth-forming side of the dental lamina implies that dental stem cells are sequestered from signals that might otherwise induce them to differentiate.

  11. Identification of sodium channel isoforms that mediate action potential firing in lamina I/II spinal cord neurons

    Directory of Open Access Journals (Sweden)

    Smith Paula L

    2011-09-01

    Full Text Available Abstract Background Voltage-gated sodium channels play key roles in acute and chronic pain processing. The molecular, biophysical, and pharmacological properties of sodium channel currents have been extensively studied for peripheral nociceptors while the properties of sodium channel currents in dorsal horn spinal cord neurons remain incompletely understood. Thus far, investigations into the roles of sodium channel function in nociceptive signaling have primarily focused on recombinant channels or peripheral nociceptors. Here, we utilize recordings from lamina I/II neurons withdrawn from the surface of spinal cord slices to systematically determine the functional properties of sodium channels expressed within the superficial dorsal horn. Results Sodium channel currents within lamina I/II neurons exhibited relatively hyperpolarized voltage-dependent properties and fast kinetics of both inactivation and recovery from inactivation, enabling small changes in neuronal membrane potentials to have large effects on intrinsic excitability. By combining biophysical and pharmacological channel properties with quantitative real-time PCR results, we demonstrate that functional sodium channel currents within lamina I/II neurons are predominantly composed of the NaV1.2 and NaV1.3 isoforms. Conclusions Overall, lamina I/II neurons express a unique combination of functional sodium channels that are highly divergent from the sodium channel isoforms found within peripheral nociceptors, creating potentially complementary or distinct ion channel targets for future pain therapeutics.

  12. Stochastic and cyclic deposition of multiple subannual laminae in an urban lake (Twin Lake, Golden Valley, Minnesota, USA)

    Science.gov (United States)

    Myrbo, A.; Ustipak, K.; Demet, B.

    2013-12-01

    Twin Lake, a small, deep, meromictic urban lake in Minneapolis, Minnesota, annually deposits two to 10 laminae that are distinguished from one another by composition and resulting color. Sediment sources are both autochthonous and allochthonous, including pure and mixed laminae of authigenic calcite, algal organic matter, and diatoms, as well as at least three distinct types of sediment gravity flow deposits. Diagenetic iron sulfide and iron phosphate phases are minor components, but can affect color out of proportion to their abundance. We used L*a*b* color from digital images of a freeze core slab, and petrographic smear slides of individual laminae, to categorize 1080 laminae deposited between 1963 and 2010 CE (based on lead-210 dating). Some causal relationships exist between the ten categories identified: diatom blooms often occur directly above the debris of gravity flows that probably disrupt the phosphate-rich monimolomnion and fertilize the surface waters; calcite whitings only occur after diatom blooms that increase calcite saturation. Stochastic events, as represented by laminae rich in siliciclastics and other terrigenous material, or shallow-water microfossils and carbonate morphologies, are the dominant sediment source. The patterns of cyclic deposition (e.g., summer and winter sedimentation) that produce 'normal' varve couplets in some lakes are continually interrupted by these stochastic events, to such an extent that spectral analysis finds only a weak one-year cycle. Sediments deposited before about 1900, and extending through the entire Holocene sequence (~10m) are varve couplets interrupted by thick (20-90 cm) debris layers, indicating that gravity flows were lower in frequency but greater in magnitude before the historical period, probably due to an increased frequency of disturbance under urban land-use.

  13. Abnormality of the spinal column in pediatric patients with lumbosacral spinal lipoma with special reference to CT findings of the lamina defects

    International Nuclear Information System (INIS)

    Yoshifuji, Kazuhisa; Ochi, Satoko; Koyanagi, Izumi; Houkin, Kiyohiro

    2009-01-01

    Lumbosacral spinal lipomas are usually associated with occult spinal dysraphism at the lumbosacral spine. During childfood, posterior arch defects in the lumbosacral spine are considered normal computed tomography (CT) findings because of the presence of interlaminar synchondrosis. In this study, we investigated the CT findings of the lumbosacral spine in the pediatric patients with lumbosacral spinal lipomas. We aimed to characterize the radiological features of the abnormal spinal column in case of spinal lipomas. Twenty-one patients (age, 1 month to 3 years) were enrolled in this study: 11 patients had conus lipoma; 10 patients, filum lipoma. All patients showed lamina defects of the lumbosacral spine on 3D-CT. The number of the defective laminae was significantly larger in the patients with conus lipomas than in those with filum lipomas. Although the appearance of lamina defects in the patients with filum lipoma was similar to the reported findings of defective laminae in normal children, these patients were characterized by mild scoliosis and asymmetry of the posterior arches localized in the lower sacrum and coccyx. On the other hand, the patients with conus lipoma were characterized by wider lamina defects that extended rostrally, 'open-door like' deformity of lamina, vertebral dysgenesis, thoracolumber scoliosis and heterotopic ossification. Such CT characterization of the abnormality of the lumbosacral spine in lipoma patients will be useful to differentiate the pathological spina bifida from the normal open posterior arches in childhood. (author)

  14. Effects of collagen microstructure and material properties on the deformation of the neural tissues of the lamina cribrosa.

    Science.gov (United States)

    Voorhees, A P; Jan, N-J; Sigal, I A

    2017-08-01

    It is widely considered that intraocular pressure (IOP)-induced deformation within the neural tissue pores of the lamina cribrosa (LC) contributes to neurodegeneration and glaucoma. Our goal was to study how the LC microstructure and mechanical properties determine the mechanical insult to the neural tissues within the pores of the LC. Polarized light microscopy was used to measure the collagen density and orientation in histology sections of three sheep optic nerve heads (ONH) at both mesoscale (4.4μm) and microscale (0.73μm) resolutions. Mesoscale fiber-aware FE models were first used to calculate ONH deformations at an IOP of 30mmHg. The results were then used as boundary conditions for microscale models of LC regions. Models predicted large insult to the LC neural tissues, with 95th percentile 1st principal strains ranging from 7 to 12%. Pores near the scleral boundary suffered significantly higher stretch compared to pores in more central regions (10.0±1.4% vs. 7.2±0.4%; p=0.014; mean±SD). Variations in material properties altered the minimum, median, and maximum levels of neural tissue insult but largely did not alter the patterns of pore-to-pore variation, suggesting these patterns are determined by the underlying structure and geometry of the LC beams and pores. To the best of our knowledge, this is the first computational model that reproduces the highly heterogeneous neural tissue strain fields observed experimentally. The loss of visual function associated with glaucoma has been attributed to sustained mechanical insult to the neural tissues of the lamina cribrosa due to elevated intraocular pressure. Our study is the first computational model built from specimen-specific tissue microstructure to consider the mechanics of the neural tissues of the lamina separately from the connective tissue. We found that the deformation of the neural tissue was much larger than that predicted by any recent microstructure-aware models of the lamina. These results

  15. Effects Aerosol of Industrial Bleach and Detergent Mixture on Mucosa Layer and Lamina Mucosa Conjunctiva in Mice

    Directory of Open Access Journals (Sweden)

    Gh. Vaezi

    2013-06-01

    Full Text Available Today bleach and detergents are being frequently used and some people use their mixture for more cleaning. Because of chemical interaction of bleach and detergent, chlorine gas was released and thereby it could be dangerous for human health. This study examined the effects of exposed toxic mixture of bleach and detergent on the Mucosa layer and Lamina mucosa conjunctiva in the mice. In this study, 42 adult male mice NMRI race weighing 35-40 gr and from age 8 to 10 weeks were divided into 6 experimental groups and one control group. Experimental groups 1-2-3 with the use of chamber, the exposed 20 minutes were exposed to spray the amount 1 cc of mixture of bleach and detergent by nebulizer. Experimental groups 4-5-6 were for 35 minutes to inhale the same amount of material. Mice killed at 24-48-72 hours after exposed and the Mucosa Layer and Lamina mucosa conjunctiva tissue was studied pathology. In the study of microscopic sections prepared of mouse mucosa layer and Lamina mucosa conjunctiva tissue experimental group comparison with the control group, significant decrease was observed in mucosa layer the have (p ≤ 0.001  and significant decrease was observed in the Lamina mucosa have(p ≤ 0. 01,  p ≤ 0.001. As a result, increasing the exposed time of mixing bleach and detergent, as time passed, increasing the tissue damage and changes.

  16. Luminal DMSO: Effects on Detrusor and Urothelial/Lamina Propria Function

    Directory of Open Access Journals (Sweden)

    Katrina J. Smith

    2014-01-01

    Full Text Available DMSO is used as a treatment for interstitial cystitis and this study examined the effects of luminal DMSO treatment on bladder function and histology. Porcine bladder was incubated without (controls or with DMSO (50% applied to the luminal surface and the release of ATP, acetylcholine, and LDH assessed during incubation and in tissues strips after DMSO incubation. Luminally applied DMSO caused ATP, Ach, and LDH release from the urothelial surface during treatment, with loss of urothelial layers also evident histologically. In strips of urothelium/lamina propria from DMSO pretreated bladders the release of both ATP and Ach was depressed, while contractile responses to carbachol were enhanced. Detrusor muscle contractile responses to carbachol were not affected by DMSO pretreatment, but neurogenic responses to electrical field stimulation were enhanced. The presence of an intact urothelium/lamina propria inhibited detrusor contraction to carbachol by 53% and this inhibition was significantly reduced in DMSO pretreated tissues. Detection of LDH in the treatment medium suggests that DMSO permeabilised urothelial membranes causing leakage of cytosolic contents including ATP and Ach rather than enhancing release of these mediators. The increase in contractile response and high levels of ATP are consistent with initial flare up in IC/PBS symptoms after DMSO treatment.

  17. Basigin/EMMPRIN/CD147 mediates neuron-glia interactions in the optic lamina of Drosophila.

    Science.gov (United States)

    Curtin, Kathryn D; Wyman, Robert J; Meinertzhagen, Ian A

    2007-11-15

    Basigin, an IgG family glycoprotein found on the surface of human metastatic tumors, stimulates fibroblasts to secrete matrix metalloproteases (MMPs) that remodel the extracellular matrix, and is thus also known as Extracellular Matrix MetalloPRotease Inducer (EMMPRIN). Using Drosophila we previously identified novel roles for basigin. Specifically, photoreceptors of flies with basigin eyes show misplaced nuclei, rough ER and mitochondria, and swollen axon terminals, suggesting cytoskeletal disruptions. Here we demonstrate that basigin is required for normal neuron-glia interactions in the Drosophila visual system. Flies with basigin mutant photoreceptors have misplaced epithelial glial cells within the first optic neuropile, or lamina. In addition, epithelial glia insert finger-like projections--capitate projections (CPs)--sites of vesicle endocytosis and possibly neurotransmitter recycling. When basigin is missing from photoreceptors terminals, CP formation between glia and photoreceptor terminals is disrupted. Visual system function is also altered in flies with basigin mutant eyes. While photoreceptors depolarize normally to light, synaptic transmission is greatly diminished, consistent with a defect in neurotransmitter release. Basigin expression in photoreceptor neurons is required for normal structure and placement of glia cells.

  18. Use of Ulex europaeus agglutinin I (UEAI) to distinguish vascular and "pseudovascular" invasion in transitional cell carcinoma of bladder with lamina propria invasion.

    Science.gov (United States)

    Larsen, M P; Steinberg, G D; Brendler, C B; Epstein, J I

    1990-01-01

    We used Ulex europaeus agglutinin I (UEAI)-immunoperoxidase staining of endothelium to study the accuracy of hematoxylin and eosin (H&E) diagnosis, occurrence, and significance of lymphvascular invasion in transitional cell carcinoma (TCC) of the bladder invading the lamina propria (Stage T1). Original histologic slides from cases (1967 to 1985) with and without vascular invasion were destained and restained with UEAI-immunoperoxidase. Only 5 of 36 biopsies originally diagnosed with lymphvascular invasion had tumor nests within endothelium-lined spaces. The 31 negative biopsies had extensive retraction artifacts lined by connective tissue and fibroblasts around tumor nests. Thirty-five control biopsies remained negative for lymphvascular invasion. Clinical follow-up of the five patients with proven lymphvascular invasion found three without progression of disease 3 to 10 yr postbiopsy, one dead of a local recurrence of TCC 1.67 yr postbiopsy, and one lost to follow-up. Based on this study, we feel that lymphvascular invasion by TCC in Stage T1 tumors is unusual, is frequently misdiagnosed on H&E stain, and does not necessarily portend a poor prognosis.

  19. Immunomodulation by Bifidobacterium infantis 35624 in the murine lamina propria requires retinoic acid-dependent and independent mechanisms.

    Directory of Open Access Journals (Sweden)

    Patrycja Konieczna

    Full Text Available Appropriate dendritic cell processing of the microbiota promotes intestinal homeostasis and protects against aberrant inflammatory responses. Mucosal CD103(+ dendritic cells are able to produce retinoic acid from retinal, however their role in vivo and how they are influenced by specific microbial species has been poorly described. Bifidobacterium infantis 35624 (B. infantis feeding to mice resulted in increased numbers of CD103(+retinaldehyde dehydrogenase (RALDH(+ dendritic cells within the lamina propria (LP. Foxp3(+ lymphocytes were also increased in the LP, while TH1 and TH17 subsets were decreased. 3,7-dimethyl-2,6-octadienal (citral treatment of mice blocked the increase in CD103(+RALDH(+ dendritic cells and the decrease in TH1 and TH17 lymphocytes, but not the increase in Foxp3(+ lymphocytes. B. infantis reduced the severity of DSS-induced colitis, associated with decreased TH1 and TH17 cells within the LP. Citral treatment confirmed that these effects were RALDH mediated. RALDH(+ dendritic cells decreased within the LP of control inflamed animals, while RALDH(+ dendritic cells numbers were maintained in the LP of B. infantis-fed mice. Thus, CD103(+RALDH(+ LP dendritic cells are important cellular targets for microbiota-associated effects on mucosal immunoregulation.

  20. Microchannel neural interface manufacture by stacking silicone and metal foil laminae

    Science.gov (United States)

    Lancashire, Henry T.; Vanhoestenberghe, Anne; Pendegrass, Catherine J.; Ajam, Yazan Al; Magee, Elliot; Donaldson, Nick; Blunn, Gordon W.

    2016-06-01

    Objective. Microchannel neural interfaces (MNIs) overcome problems with recording from peripheral nerves by amplifying signals independent of node of Ranvier position. Selective recording and stimulation using an MNI requires good insulation between microchannels and a high electrode density. We propose that stacking microchannel laminae will improve selectivity over single layer MNI designs due to the increase in electrode number and an improvement in microchannel sealing. Approach. This paper describes a manufacturing method for creating MNIs which overcomes limitations on electrode connectivity and microchannel sealing. Laser cut silicone—metal foil laminae were stacked using plasma bonding to create an array of microchannels containing tripolar electrodes. Electrodes were DC etched and electrode impedance and cyclic voltammetry were tested. Main results. MNIs with 100 μm and 200 μm diameter microchannels were manufactured. High electrode density MNIs are achievable with electrodes present in every microchannel. Electrode impedances of 27.2 ± 19.8 kΩ at 1 kHz were achieved. Following two months of implantation in Lewis rat sciatic nerve, micro-fascicles were observed regenerating through the MNI microchannels. Significance. Selective MNIs with the peripheral nervous system may allow upper limb amputees to control prostheses intuitively.

  1. Lamina specific loss of inhibition may lead to distinct neuropathic manifestations: a computational modeling approach

    Directory of Open Access Journals (Sweden)

    Erick Javier Argüello Prada

    Full Text Available Introduction It has been reported that inhibitory control at the superficial dorsal horn (SDH can act in a regionally distinct manner, which suggests that regionally specific subpopulations of SDH inhibitory neurons may prevent one specific neuropathic condition. Methods In an attempt to address this issue, we provide an alternative approach by integrating neuroanatomical information provided by different studies to construct a network-model of the SDH. We use Neuroids to simulate each neuron included in that model by adapting available experimental evidence. Results Simulations suggest that the maintenance of the proper level of pain sensitivity may be attributed to lamina II inhibitory neurons and, therefore, hyperalgesia may be elicited by suppression of the inhibitory tone at that lamina. In contrast, lamina III inhibitory neurons are more likely to be responsible for keeping the nociceptive pathway from the mechanoreceptive pathway, so loss of inhibitory control in that region may result in allodynia. The SDH network-model is also able to replicate non-linearities associated to pain processing, such as Aβ-fiber mediated analgesia and frequency-dependent increase of the neural response. Discussion By incorporating biophysical accuracy and newer experimental evidence, the SDH network-model may become a valuable tool for assessing the contribution of specific SDH connectivity patterns to noxious transmission in both physiological and pathological conditions.

  2. The prognosis significance and application value of peritoneal elastic lamina invasion in colon cancer.

    Science.gov (United States)

    Lu, Jun; Hu, Xiumei; Meng, Yutong; Zhao, Hongying; Cao, Qing; Jin, Mulan

    2018-01-01

    The aims of this study were to evaluate the associations between peritoneal elastic lamina invasion (ELI) and the clinicopathological prognostic factors of colon cancer, to evaluate the feasibility of ELI with use of an elastic stain to help diagnose serosal invasion of colon cancer in routine practice, so as to help us to provide a more accurate estimate for prognosis and stage of patients and a marker for postoperative treatment. 254 cases with colon cancer were included in the study. According to the presence of elastic lamina (EL) and elastic lamina invasion (ELI), all cases were divided into four groups: pT3 EL negative (pT3 EL (-)), pT3 ELI positive (pT3 ELI (+)), pT3 ELI negative (pT3 ELI (-)) and pT4a. Statistical analysis was used to analyze the relationship between elastic lamina invasion and other established adverse histologic features. The EL and ELI positive rates were 81.5% and 42.1% respectively. There were significant differences in mph node metastasis, venous invasion and tumor buds between pT3 ELI (-) and pT3 ELI (+), pT3 ELI (-) and pT4a. There was no significant difference in same factors between pT3 ELI (+) and pT4a. In pT3 stage, there were significant differences in lymph node metastasis, perineural invasion and tumor buds between EL (-) and ELI (+). There were no significant differences in same factors between EL (-) and ELI (-). EL was detected less frequently in right-sided tumors compared with left-sided tumors. ELI might be the prognostic factors of colon cancer with II stage and might be the marker of postoperative adjuvant chemotherapy. Patients with pT3 ELI (+) might have similar prognosis to patients with pT4a. For patients with pT3 colon cancer, EL(-) might have similar prognosis as ELI (-) and might take the same therapy. In addition, the right half colon EL positive rate was lower than the left colon. Elastic staining might be a useful tool to help determine the invasive depth and stage of colon cancer.

  3. Clinical study of bilateral decompression via vertebral lamina fenestration for lumbar interbody fusion in the treatment of lower lumbar instability

    OpenAIRE

    GUO, SHUGUANG; SUN, JUNYING; TANG, GENLIN

    2013-01-01

    The aim of this study was to observe the clinical effects of bilateral decompression via vertebral lamina fenestration for lumbar interbody fusion in the treatment of lower lumbar instability. The 48 patients comprised 27 males and 21 females, aged 47?72 years. Three cases had first and second degree lumbar spondylolisthesis and all received bilateral vertebral lamina fenestration for posterior lumbar interbody fusion (PLIF) using a threaded fusion cage (TFC), which maintains the three-column...

  4. Correlation of radiographic size and the presence of radiopaque lamina with histological findings in 70 periapical lesions.

    Science.gov (United States)

    Carrillo, Celia; Penarrocha, Miguel; Ortega, Bárbara; Martí, Eva; Bagán, José Vicente; Vera, Francisco

    2008-08-01

    This study was conducted to relate the histological diagnosis of chronic inflammatory periapical lesions with the radiographic images of these lesions. A total of 70 biopsy specimens obtained during periapical surgery were stained with hematoxylin and eosin and examined under a microscope. Histological analysis established the diagnosis as granuloma, cyst, or scar tissue. The location of the lesion was recorded, as were the radiographic size (maximum and minimum diameter in mm and area in mm(2)) and the presence of radiopaque lamina around the lesion, using an image analyzing system. The distribution of the biopsy specimens was 65.7% granulomas, 25.7% scar tissue, and 8.6% cysts, 1 of which was a keratocyst. The largest lesions were cysts and epithelialized granulomas, with statistically significant differences. Radiopaque lamina was observed around 9 lesions; of these, only 2 were histologically diagnosed as cysts, with the rest as granulomas. Most of the apical lesions were granulomas. Cysts had the largest radiotransparent images; however, in the 70 cases studied, neither the radiographic size nor the presence of associated radiopaque lamina alone was sufficient to determine the type of lesion. Histological analysis is required.

  5. IgA class switch occurs in the organized nasopharynx- and gut-associated lymphoid tissue, but not in the diffuse lamina propria of airways and gut.

    Science.gov (United States)

    Shikina, Takashi; Hiroi, Takachika; Iwatani, Kohichi; Jang, Myoung Ho; Fukuyama, Satoshi; Tamura, Manabu; Kubo, Takeshi; Ishikawa, Hiromichi; Kiyono, Hiroshi

    2004-05-15

    Secretory IgA plays a crucial role in the host immune response as a first line of defense. A recent demonstration of in situ IgA class switching in intestinal lamina propria provided an opportunity to reconsider the model for the homing of IgA-committed B cells characterized by distinctive trafficking patterns to effector sites. Those effector sites depend on the organized mucosa-associated lymphoid tissues as their site of induction. In this report we show the preferential presence of IgM(+)B220(+) and IgA(+)B220(+) cells belonging to pre- and post-IgA isotype class-switched cells in the organized mucosa-associated lymphoid tissues, such as nasopharynx-associated lymphoid tissues, isolated lymphoid follicles, and Peyer's patches, and the defect of those populations in the diffuse effector tissues, such as the nasal passage and intestinal lamina propria. Consistent with these findings, the expressions of a series of IgA isotype class switch recombination-related molecules, including activation-induced cytidine deaminase, Ialpha-C micro circle transcripts, and Ialpha-C micro circle transcripts, were selectively detected in these organized mucosa-associated lymphoid structures, but not in the diffuse mucosal effector sites. Taken together, these findings suggest that IgA isotype class switching occurs only in the organized mucosa-associated lymphoid organs (e.g., nasopharynx-associated lymphoid tissues, isolated lymphoid follicles, and Peyer's patches), but not in the diffuse effector tissues of the upper respiratory and gastrointestinal tracts.

  6. Oxytocin-induced antinociception in the spinal cord is mediated by a subpopulation of glutamatergic neurons in lamina I-II which amplify GABAergic inhibition

    Directory of Open Access Journals (Sweden)

    Schlichter Rémy

    2008-05-01

    Full Text Available Abstract Background Recent evidence suggests that oxytocin (OT, secreted in the superficial spinal cord dorsal horn by descending axons of paraventricular hypothalamic nucleus (PVN neurons, produces antinociception and analgesia. The spinal mechanism of OT is, however, still unclear and requires further investigation. We have used patch clamp recording of lamina II neurons in spinal cord slices and immunocytochemistry in order to identify PVN-activated neurons in the superficial layers of the spinal cord and attempted to determine how this neuronal population may lead to OT-mediated antinociception. Results We show that OT released during PVN stimulation specifically activates a subpopulation of lamina II glutamatergic interneurons which are localized in the most superficial layers of the dorsal horn of the spinal cord (lamina I-II. This OT-specific stimulation of glutamatergic neurons allows the recruitment of all GABAergic interneurons in lamina II which produces a generalized elevation of local inhibition, a phenomenon which might explain the reduction of incoming Aδ and C primary afferent-mediated sensory messages. Conclusion Our results obtained in lamina II of the spinal cord provide the first clear evidence of a specific local neuronal network that is activated by OT release to induce antinociception. This OT-specific pathway might represent a novel and interesting therapeutic target for the management of neuropathic and inflammatory pain.

  7. Gut-associated lymphoid tissue contains the molecular machinery to support T-cell-dependent and T-cell-independent class switch recombination.

    Science.gov (United States)

    Barone, F; Patel, P; Sanderson, J D; Spencer, J

    2009-11-01

    A PRoliferation-Inducing Ligand (APRIL) is a secreted cytokine member of the tumor necrosis factor family. It is a B-cell survival factor that also induces class switch recombination (CSR) toward immunoglobulin A (IgA), independent of T cells. It is therefore an important contributor to the maintenance of the mucosal immunological barrier, which has been linked to a putative extrafollicular inductive phase of the IgA response in lamina propria. By immunohistochemistry (IHC) and quantitative real-time PCR (qRT-PCR) on microdissected tissue from normal human gut, we observed APRIL expression, together with TACI (transmembrane activator and CAML interactor) and BCMA (B-cell maturation antigen), in gut-associated lymphoid tissue (GALT), lamina propria, and in the epithelium of stomach, small and large intestine, and rectum. However, no activation-induced cytidine deaminase (AID) expression (an absolute requirement for class switching) was detected in lamina propria by IHC or qRT-PCR. APRIL and its receptors were only observed alongside AID in GALT, showing that GALT contains the apparatus to support both T-independent and T-dependent routes to IgA CSR.

  8. Strengthening of Shear Walls

    DEFF Research Database (Denmark)

    Hansen, Christian Skodborg

    The theory for concrete structures strengthened with fiber reinforced polymer materials has been developing for approximately two decades, and there are at the present time numerous guidelines covering strengthening of many commonly encountered structural building elements. Strengthening of in...... that describes a unit width strip of a strengthened disk. The unit width strip is named a strengthened concrete tension member and contains a single tensile crack and four debonding cracks. Analysis of the member results in closed form expressions for the load-crack opening relationship. Further analysis...... of the response, results in the ability to determine and characterize the two-way crack propagation, i.e. the relationship between tensile cracking in the concrete and interface debonding between strengthening and concrete. Using the load-crack opening relationship from the strengthened concrete tension member...

  9. Connective tissue growth factor is necessary for retinal capillary basal lamina thickening in diabetic mice

    NARCIS (Netherlands)

    Kuiper, Esther J.; van Zijderveld, Rogier; Roestenberg, Peggy; Lyons, Karen M.; Goldschmeding, Roel; Klaassen, Ingeborg; van Noorden, Cornelis J. F.; Schlingemann, Reinier O.

    2008-01-01

    Experimental prevention of basal lamina (BL) thickening of retinal capillaries ameliorates early vascular changes caused by diabetes. Connective tissue growth factor (CTGF) is upregulated early in diabetes in the human retina and is a potent inducer of expression of BL components. We hypothesize

  10. Boomerang deformity of cervical spinal cord migrating between split laminae after laminoplasty.

    Science.gov (United States)

    Kimura, S; Gomibuchi, F; Shimoda, H; Ikezawa, Y; Segawa, H; Kaneko, F; Uchiyama, S; Homma, T

    2000-04-01

    Patients with cervical compression myelopathy were studied to elucidate the mechanism underlying boomerang deformity, which results from the migration of the cervical spinal cord between split laminae after laminoplasty with median splitting of the spinous processes (boomerang sign). Thirty-nine cases, comprising 25 patients with cervical spondylotic myelopathy, 8 patients with ossification of the posterior longitudinal ligament, and 6 patients with cervical disc herniation with developmental canal stenosis, were examined. The clinical and radiological findings were retrospectively compared between patients with (B group, 8 cases) and without (C group, 31 cases) boomerang sign. Moderate increase of the grade of this deformity resulted in no clinical recovery, although there was no difference in clinical recovery between the two groups. Most boomerang signs developed at the C4/5 and/or C5/6 level, where maximal posterior movement of the spinal cord was achieved. Widths between lateral hinges and between split laminae in the B group were smaller than in the C group. Flatness of the spinal cord in the B group was more severe than in the C group. In conclusion, the boomerang sign was caused by posterior movement of the spinal cord, narrower enlargement of the spinal canal and flatness of the spinal cord.

  11. Severe hypoplasia of the omasal laminae in a Japanese Black steer with chronic bloat--a case report.

    Science.gov (United States)

    Takagi, Mitsuhiro; Mukai, Shuhei; Fushimi, Yasuo; Matsushita, Kouhei; Miyoshi, Nobuaki; Yasuda, Nobuhiro; Kitajima, Hideo; Takamure, Senro; Matsushita, Toshihiko; Kitamura, Nobuo; Deguchi, Eisaburo

    2007-12-01

    An 11-month-old Japanese Black steer with chronic bloat underwent clinical and histological analyses. During the observation period, it showed normal appetite and fecal volume but persistent chronic bloat symptoms. Compared to controls, the steer's feces contained undigested large straws. Necropsy revealed normal rumen, reticulum, and abomasum but a small omasum. The rumen, reticulum, and abomasum mucosa was normal, with well-developed ruminal papillae. However, severe hypoplasia of the omasal laminae was observed along with hypoplasia reticular groove and ruminoreticular fold. The contents of the reticulum, omasum, and abomasums comprised undigested large sized hay particles. The omasum papillae showed no pathological abnormalities. This is a rare case of a steer with chronic bloat probably caused by severe hypoplasia of the omasal laminae.

  12. Squeeze strengthening of magnetorheological fluids using mixed mode operation

    Science.gov (United States)

    Becnel, A. C.; Sherman, S. G.; Hu, W.; Wereley, N. M.

    2015-05-01

    This research details a novel method of increasing the shear yield stress of magnetorheological fluids by combining shear and squeeze modes of operation to manipulate particle chain structures, so-called squeeze strengthening. Using a custom built Searle cell magnetorheometer, which is a model device emulating a rotary magnetorheological energy absorber (MREA), the contribution of squeeze strengthening to the total controllable yield force is experimentally investigated. Using an eccentric rotating inner cylinder, characterization data from large (1 mm) and small (0.25 mm) nominal gap geometries are compared to investigate the squeeze strengthening effect. Details of the experimental setup and method are presented, and a hybrid model is used to explain experimental trends. This study demonstrates that it is feasible, utilizing squeeze strengthening to increase yield stress, to either (1) design a rotary MREA of a given volume to achieve higher energy absorption density (energy absorbed normalized by active fluid volume), or (2) reduce the volume of a given rotary MREA to achieve the same energy absorption density.

  13. Downregulation of DmMANF in Glial Cells Results in Neurodegeneration and Affects Sleep and Lifespan in Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Lucyna Walkowicz

    2017-11-01

    Full Text Available In Drosophila melanogaster, mesencephalic astrocyte-derived neurotrophic factor (DmMANF is an evolutionarily conserved ortholog of mammalian MANF and cerebral dopamine neurotrophic factor (CDNF, which have been shown to promote the survival of dopaminergic neurons in the brain. We observed especially high levels of DmMANF in the visual system of Drosophila, particularly in the first optic neuropil (lamina. In the lamina, DmMANF was found in glial cells (surface and epithelial glia, photoreceptors and interneurons. Interestingly, silencing of DmMANF in all neurons or specifically in photoreceptors or L2 interneurons had no impact on the structure of the visual system. However, downregulation of DmMANF in glial cells induced degeneration of the lamina. Remarkably, this degeneration in the form of holes and/or tightly packed membranes was observed only in the lamina epithelial glial cells. Those membranes seem to originate from the endoplasmic reticulum, which forms autophagosome membranes. Moreover, capitate projections, the epithelial glia invaginations into photoreceptor terminals that are involved in recycling of the photoreceptor neurotransmitter histamine, were less numerous after DmMANF silencing either in neurons or glial cells. The distribution of the alpha subunit of Na+/K+-ATPase protein in the lamina cell membranes was also changed. At the behavioral level, silencing of DmMANF either in neurons or glial cells affected the daily activity/sleep pattern, and flies showed less activity during the day but higher activity during the night than did controls. In the case of silencing in glia, the lifespan of flies was also shortened. The obtained results showed that DmMANF regulates many functions in the brain, particularly those dependent on glial cells.

  14. Antinociceptive action of oxytocin involves inhibition of potassium channel currents in lamina II neurons of the rat spinal cord

    Directory of Open Access Journals (Sweden)

    Darbon Pascal

    2009-11-01

    Full Text Available Abstract Background Growing evidence in the literature shows that oxytocin (OT has a strong spinal anti-nociceptive action. Oxytocinergic axons originating from a subpopulation of paraventricular hypothalamic neurons establish synaptic contacts with lamina II interneurons but little is known about the functional role of OT with respect to neuronal firing and excitability. Results Using the patch-clamp technique, we have recorded lamina II interneurons in acute transverse lumbar spinal cord slices of rats (15 to 30 days old and analyzed the OT effects on action potential firing ability. In the current clamp mode, we found that bath application of a selective OT-receptor agonist (TGOT reduced firing in the majority of lamina II interneurons exhibiting a bursting firing profile, but never in those exhibiting a single spike discharge upon depolarization. Interestingly, OT-induced reduction in spike frequency and increase of firing threshold were often observed, leading to a conversion of the firing profile from repetitive and delayed profiles into phasic ones and sometimes further into single spike profile. The observed effects following OT-receptor activation were completely abolished when the OT-receptor agonist was co-applied with a selective OT-receptor antagonist. In current and voltage clamp modes, we show that these changes in firing are strongly controlled by voltage-gated potassium currents. More precisely, transient IA currents and delayed-rectifier currents were reduced in amplitude and transient IA current was predominantly inactivated after OT bath application. Conclusion This effect of OT on the firing profile of lamina II neurons is in good agreement with the antinociceptive and analgesic properties of OT described in vivo.

  15. Bait-lamina assay as a tool to assess the effects of metal contamination in the feeding activity of soil invertebrates within a uranium mine area

    International Nuclear Information System (INIS)

    Andre, A.; Antunes, S.C.; Goncalves, F.; Pereira, R.

    2009-01-01

    As part of the tier 2 of a site-specific risk assessment, this study was the first reporting an intensive in situ application of the bait-lamina assay; two exposure periods (7 and 14 days) were tested during four seasons in ten different sites, within a uranium mine area and at two different depths. The most contaminated sites (by deposition of sludge from the effluent treatment pond) were discriminated after 14 days of exposure because extremely low percentages of feeding activity were recorded. Previous sub-lethal ecotoxicological assays, already had demonstrated that the habitat function of these soils is compromised. Nevertheless, seasonality has proved to have a significant influence on responses. Thus to strength conclusions about the impact of contaminants, the in situ bait-lamina assay should be performed on different annual seasons, at least for temperate regions. It was also found that some environmental parameters (e.g. soil moisture and litter) can act as confounding factors in the bait-lamina assay. - Bait-lamina assay for in situ evaluation of soil functions under site-specific risk assessments.

  16. Using the trans-lamina terminalis route via a pterional approach to resect a retrochiasmatic craniopharyngioma involving the third ventricle.

    Science.gov (United States)

    Weil, Alexander G; Robert, Thomas; Alsaiari, Sultan; Obaid, Sami; Bojanowski, Michel W

    2016-01-01

    Retrochiasmatic craniopharyngiomas involving the anterior third ventricle are challenging to access. Although the pterional approach is a common route for suprasellar lesions, when the craniopharyngioma extends behind the chiasma into the third ventricle, access is even more difficult, and the lamina terminalis may offer a good working window. The translamina terminalis approach provides direct access to the retrochiasmatic portion of the tumor with minimal brain retraction and no manipulation of the visual nerves. In this video, we emphasize the utility of using the lamina terminalis corridor to resect the retrochiasmatic intraventricular portion of a craniopharyngioma. The video can be found here: https://youtu.be/hrLNC0hDKe4 .

  17. Long-term trends in the northern extratropical ozone laminae with focus on European stations

    Czech Academy of Sciences Publication Activity Database

    Laštovička, Jan; Križan, Peter; Kozubek, Michal

    2014-01-01

    Roč. 120, December (2014), s. 88-95 ISSN 1364-6826 R&D Projects: GA MŠk LD12070; GA ČR GAP209/10/1792 Institutional support: RVO:68378289 Keywords : ozone laminae * long-term trends * atmospheric dynamics Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.474, year: 2014 http://www.sciencedirect.com/science/article/pii/S1364682614002119

  18. In Vivo Changes in Lamina Cribrosa Microarchitecture and Optic Nerve Head Structure in Early Experimental Glaucoma.

    Directory of Open Access Journals (Sweden)

    Kevin M Ivers

    Full Text Available The lamina cribrosa likely plays an important role in retinal ganglion cell axon injury in glaucoma. We sought to (1 better understand optic nerve head (ONH structure and anterior lamina cribrosa surface (ALCS microarchitecture between fellow eyes of living, normal non-human primates and (2 characterize the time-course of in vivo structural changes in the ONH, ALCS microarchitecture, and retinal nerve fiber layer thickness (RNFLT in non-human primate eyes with early experimental glaucoma (EG. Spectral domain optical coherence tomography (SDOCT images of the ONH were acquired cross-sectionally in six bilaterally normal rhesus monkeys, and before and approximately every two weeks after inducing unilateral EG in seven rhesus monkeys. ONH parameters and RNFLT were quantified from segmented SDOCT images. Mean ALCS pore area, elongation and nearest neighbor distance (NND were quantified globally, in sectors and regionally from adaptive optics scanning laser ophthalmoscope images. In bilaterally normal monkeys, ONH parameters were similar between fellow eyes with few inter-eye differences in ALCS pore parameters. In EG monkeys, an increase in mean ALCS Depth (ALCSD was the first structural change measured in 6 of 7 EG eyes. A decrease in mean minimum rim width (MRW simultaneously accompanied this early change in 4 of 6 EG eyes and was the first structural change in the 7th EG eye. Mean ALCS pore parameters were among the first or second changes measured in 4 EG eyes. Mean ALCS pore area and NND increased in superotemporal and temporal sectors and in central and peripheral regions at the first time-point of change in ALCS pore geometry. RNFLT and/or mean ALCS radius of curvature were typically the last parameters to initially change. Survival analyses found mean ALCSD was the only parameter to significantly show an initial change prior to the first measured loss in RNFLT across EG eyes.

  19. Serotonin Immunoreactive Cells and Nerve Fibers in the Mucosa of ...

    African Journals Online (AJOL)

    hydroxytryptamine) immunoreactivity in the pyloric mucosa of the rat stomach. The immunoreactive elements included the endocrine cells, mast cells and mucosal nerve fibers in the lamina propria. The immunopositive endocrine cells were oval in ...

  20. Mechanical properties of ramie fiber reinforced epoxy lamina composite for socket prosthesis

    Directory of Open Access Journals (Sweden)

    Tresna Soemardi

    2010-10-01

    Full Text Available This paper presents an investigation into the application of natural fiber composite especially ramie fiber reinforced epoxy lamina composite for socket prosthesis. The research focuses on the tensile and shear strength from ramie fiber reinforced epoxy lamina composite which will be applied as alternative material for socket prosthesis. The research based on American Society for Testing Material (ASTM standard D 3039/D 3039M for tensile strength and ASTM D 4255/D 4255M-83 for shear strength. The ramie fiber applied is a fiber continue 100 % Ne14'S with Epoxy Resin Bakelite EPR 174 as matrix and Epoxy Hardener V-140 as hardener. The sample composite test made by hand lay up method. Multiaxial characteristic from ramie fiber reinforced epoxy composite will be compared with ISO standard for plastic/polymer for health application and refers strength of material application at Prosthetics and Orthotics. The analysis was completed with the mode of the failure and the failure criterion observation by using Scanning Electron Microscope (SEM. Based on results of the research could be concluded that ramie fiber reinforced epoxy composite could be developed further as the alternative material for socket prosthesis on Vf 40-50%. Results of the research will be discussed in more detail in this paper.

  1. An examination of the damage tolerance enhancement of carbon/epoxy using an outer lamina of spectra (R)

    Science.gov (United States)

    Lance, D. G.; Nettles, A. T.

    1991-01-01

    Low velocity instrumented impact testing was utilized to examine the effects of an outer lamina of ultra-high molecular weight polyethylene (Spectra) on the damage tolerance of carbon epoxy composites. Four types of 16-ply quasi-isotropic panels (0, +45, 90, -45) were tested. Some panels contained no Spectra, while others had a lamina of Spectra bonded to the top (impacted side), bottom, or both sides of the composite plates. The specimens were impacted with energies up to 8.5 J. Force time plots and maximum force versus impact energy graphs were generated for comparison purposes. Specimens were also subjected to cross-sectional analysis and compression after impact tests. The results show that while the Spectra improved the maximum load that the panels could withstand before fiber breakage, the Spectra seemingly reduced the residual strength of the composites.

  2. Structure and barrier properties of human embryonic stem cell-derived retinal pigment epithelial cells are affected by extracellular matrix protein coating.

    Science.gov (United States)

    Sorkio, Anni; Hongisto, Heidi; Kaarniranta, Kai; Uusitalo, Hannu; Juuti-Uusitalo, Kati; Skottman, Heli

    2014-02-01

    Extracellular matrix (ECM) interactions play a vital role in cell morphology, migration, proliferation, and differentiation of cells. We investigated the role of ECM proteins on the structure and function of human embryonic stem cell-derived retinal pigment epithelial (hESC-RPE) cells during their differentiation and maturation from hESCs into RPE cells in adherent differentiation cultures on several human ECM proteins found in native human Bruch's membrane, namely, collagen I, collagen IV, laminin, fibronectin, and vitronectin, as well as on commercial substrates of xeno-free CELLstart™ and Matrigel™. Cell pigmentation, expression of RPE-specific proteins, fine structure, as well as the production of basal lamina by hESC-RPE on different protein coatings were evaluated after 140 days of differentiation. The integrity of hESC-RPE epithelium and barrier properties on different coatings were investigated by measuring transepithelial resistance. All coatings supported the differentiation of hESC-RPE cells as demonstrated by early onset of cell pigmentation and further maturation to RPE monolayers after enrichment. Mature RPE phenotype was verified by RPE-specific gene and protein expression, correct epithelial polarization, and phagocytic activity. Significant differences were found in the degree of RPE cell pigmentation and tightness of epithelial barrier between different coatings. Further, the thickness of self-assembled basal lamina and secretion of the key ECM proteins found in the basement membrane of the native RPE varied between hESC-RPE cultured on compared protein coatings. In conclusion, this study shows that the cell culture substrate has a major effect on the structure and basal lamina production during the differentiation and maturation of hESC-RPE potentially influencing the success of cell integrations and survival after cell transplantation.

  3. Cholera toxin B subunit labeling in lamina II of spinal cord dorsal horn following chronic inflammation in rats.

    Science.gov (United States)

    Ma, Qing Ping; Tian, Li

    2002-07-26

    We have investigated the effect of inflammation on the labeling pattern of cholera toxin B subunit (CTB)-conjugated horseradish peroxidase, an A-fiber marker, by an intra-sciatic nerve injection of the tracer. Following chronic inflammation in one hind paw in rats, there was substantial CTB labeling in lamina II of the spinal dorsal horn, which is normally absent. However, there was no change in the labeling pattern of wheat germ agglutinin or fluoride resistant acid phosphatase/thiamine monophosphatase, two C-fiber markers. The CTB labeling in lamina II after peripheral nerve injury has been interpreted as central sprouting of A-fibers or uptake of the tracer by injured C-fibers. Our results suggest that chronic inflammation and nerve injury may share some common mechanisms in generating allodynia and hyperalgesia.

  4. Strategy for Strengthening Farmer Groups by Institutional Strengthening

    Directory of Open Access Journals (Sweden)

    Purbayu Budi Santoso

    2015-08-01

    Full Text Available Agriculture sector becomes a spotlight because this sector will be full of potential but the welfare of farmers who become the leading actor is not guaranteed and has a poor tendency. The purpose of this study is to formulate strategies to strengthen farmers' groups in order to create the marketing of the agricultural sector that benefit farmers. The method used to achieve this goal is to use a qualitative approach and Analytical Network Process. In addition to the secondary data obtained from several agencies, this study also uses primary data obtained by in-depth interviews and observations. This research results a priority of aspects of the institutional strengthening of farmer groups as well as priority issues and priorities of the solution of each aspect. In addition, the priority of alternative strategies resulted based on the problems and solutions that have been analyzed in order to solve the problems in the institutional strengthening of farmer groups in Demak.

  5. Biointegration of the osteo-odonto lamina in the modified osteo-odonto keratoprosthesis: engineering of tissue to restore lost vision.

    Science.gov (United States)

    Sawatari, Yoh; Marx, Robert E; Perez, Victor L; Parel, Jean-Marie

    2013-01-01

    The modified osteo-odonto keratoprosthesis (MOOKP) is a biologic keratoprosthesis that is used to treat a severely scarred cornea. The procedure involves multiple stages, including the transplantation of buccal mucosa to the damaged ocular surface and the implantation of an osteo-odonto lamina with a mounted polymethylmethacrylate lens. Among the keratoprostheses currently available, the MOOKP has proven to be the most effective based on the number of patients who have undergone the procedure and the duration of documented follow-up. Upon successful biointegration of the osteo-odonto lamina, the keratoprosthesis is able to resist resorption, provide stability, and prevent bacterial invasion and epithelial ingrowth. The effectiveness of the MOOKP is dependent on the anatomic and physiologic characteristics of the dental tissues and periodontal ligament.

  6. Cloning and Characterization of Sf9 Cell Lamin and the Lamin Conformational Changes during Autographa californica multiple nucleopolyhedrovirus Infection

    Directory of Open Access Journals (Sweden)

    Wenqiang Wei

    2016-05-01

    Full Text Available At present, the details of lamina alterations after baculovirus infection remain elusive. In this study, a lamin gene in the Sf9 cell line of Spodoptera frugiperda was cloned. The open reading frame (orf of the Sf9 lamin was 1860 bp and encoded a protein with a molecular weight of 70 kDa. A transfection assay with a red fluorescence protein (rfp-lamin fusion protein indicated that Sf9 lamin was localized in the nuclear rim. Transmission electron microscopy observations indicated that Autographa californica multiple nucleopolyhedrovirus (AcMNPV nucleocapsids may pass through the nuclear envelope. Immunofluorescence assay indicated that the lamina showed a ruffled staining pattern with the formation of invaginations in the Sf9 cells infected with AcMNPV, while it was evenly distributed at the nuclear periphery of mock-infected cells. Western blotting results indicated that the total amount of lamin in the baculovirus-infected Sf9 cells was significantly decreased compared with the mock-infected cells. These results imply that AcMNPV infection induces structural and biochemical rearrangements of lamina of Sf9 cells.

  7. Plasma cell granuloma of lip

    Directory of Open Access Journals (Sweden)

    B Sabarinath

    2012-01-01

    Full Text Available Plasma cells are medium-sized round-to-oval cells with eccentrically placed nuclei, usually found in the red pulp of the spleen, tonsils, medulla of the lymph nodes, nasal mucosa, upper airway, lamina propria of the gastrointestinal tract, and sites of inflammation. Plasma cell granuloma is a rare reactive tumor-like proliferation composed chiefly of plasmacytic infiltrate. Here, we present a case of plasma cell granuloma of lip in a female patient.

  8. Vigas de madeira laminada colada com laminas pre-classificadas de eucalyptus grandis

    OpenAIRE

    Grohmann, Sandra Zampieri

    1998-01-01

    Dissertação (Mestrado) - Universidade Federal de Santa Catarina, Centro Tecnologico Comprovar a viabilidade de realização e desempenho de vigas de madeira laminada colada de Eucalyptus grandis classificadas de acordo com sua rigidez cujas lâminas estão divididas em classes de resistência onde o parâmetro de comparação é o módulo de elasticidade longitudinal. Para isso caracterizou-se física e mecanicamente a madeira e fez-se a classificação das laminas em grupos de acordo com o módulo de e...

  9. Differential nuclear remodeling of mammalian somatic cells by Xenopus laevis oocyte and egg cytoplasm

    International Nuclear Information System (INIS)

    Alberio, Ramiro; Johnson, Andrew D.; Stick, Reimer; Campbell, Keith H.S.

    2005-01-01

    The mechanisms governing nuclear reprogramming have not been fully elucidated yet; however, recent studies show a universally conserved ability of both oocyte and egg components to reprogram gene expression in somatic cells. The activation of genes associated with pluripotency by oocyte/egg components may require the remodeling of nuclear structures, such that they can acquire the features of early embryos and pluripotent cells. Here, we report on the remodeling of the nuclear lamina of mammalian cells by Xenopus oocyte and egg extracts. Lamin A/C is removed from somatic cells incubated in oocyte and egg extracts in an active process that requires permeable nuclear pores. Removal of lamin A/C is specific, since B-type lamins are not changed, and it is not dependent on the incorporation Xenopus egg specific lamin III. Moreover, transcriptional activity is differentially regulated in somatic cells incubated in the extracts. Pol I and II transcriptions are maintained in cells in oocyte extracts; however, both activities are abolished in egg extracts. Our study shows that components of oocyte and egg extracts can modify the nuclear lamina of somatic cells and that this nuclear remodeling induces a structural change in the nucleus which may have implications for transcriptional activity. These experiments suggest that modifications in the nuclear lamina structure by the removal of somatic proteins and the incorporation of oocyte/egg components may contribute to the reprogramming of somatic cell nuclei and may define a characteristic configuration of pluripotent cells

  10. Mechanical behavior and strengthening mechanisms in ultrafine grain precipitation-strengthened aluminum alloy

    International Nuclear Information System (INIS)

    Ma, Kaka; Wen, Haiming; Hu, Tao; Topping, Troy D.; Isheim, Dieter; Seidman, David N.; Lavernia, Enrique J.; Schoenung, Julie M.

    2014-01-01

    To provide insight into the relationships between precipitation phenomena, grain size and mechanical behavior in a complex precipitation-strengthened alloy system, Al 7075 alloy, a commonly used aluminum alloy, was selected as a model system in the present study. Ultrafine-grained (UFG) bulk materials were fabricated through cryomilling, degassing, hot isostatic pressing and extrusion, followed by a subsequent heat treatment. The mechanical behavior and microstructure of the materials were analyzed and compared directly to the coarse-grained (CG) counterpart. Three-dimensional atom-probe tomography was utilized to investigate the intermetallic precipitates and oxide dispersoids formed in the as-extruded UFG material. UFG 7075 exhibits higher strength than the CG 7075 alloy for each equivalent condition. After a T6 temper, the yield strength (YS) and ultimate tensile strength (UTS) of UFG 7075 achieved 734 and 774 MPa, respectively, which are ∼120 MPa higher than those of the CG equivalent. The strength of as-extruded UFG 7075 (YS: 583 MPa, UTS: 631 MPa) is even higher than that of commercial 7075-T6. More importantly, the strengthening mechanisms in each material were established quantitatively for the first time for this complex precipitation-strengthened system, accounting for grain-boundary, dislocation, solid-solution, precipitation and oxide dispersoid strengthening contributions. Grain-boundary strengthening was the predominant mechanism in as-extruded UFG 7075, contributing a strength increment estimated to be 242 MPa, whereas Orowan precipitation strengthening was predominant in the as-extruded CG 7075 (∼102 MPa) and in the T6-tempered materials, and was estimated to contribute 472 and 414 MPa for CG-T6 and UFG-T6, respectively

  11. Preloading Effect on Strengthening Efficiency of RC Beams Strengthened with Non- and Pretensioned NSM Strips

    Directory of Open Access Journals (Sweden)

    Renata Kotynia

    2018-02-01

    Full Text Available The near surface mounted (NSM technique has been shown to be one of the most promising methods for upgrading reinforced concrete (RC structures. Many tests carried out on RC members strengthened in flexure with NSM fiber-reinforced polymer (FRP systems have demonstrated greater strengthening efficiency than the use of externally-bonded (EB FRP laminates. Strengthening with simultaneous pretensioning of the FRP results in improvements in the serviceability limit state (SLS conditions, including the increased cracking moment and decreased deflections. The objective of the reported experimental program, which consisted of two series of RC beams strengthened in flexure with NSM CFRP strips, was to investigate the influence of a number of parameters on the strengthening efficiency. The test program focused on an analysis of the effects of preloading on the strengthening efficiency which has been investigated very rarely despite being one of the most important parameters to be taken into account in strengthening design. Two preloading levels were considered: the beam self-weight only, which corresponded to stresses on the internal longitudinal reinforcement of 25% and 14% of the yield stress (depending on a steel reinforcement ratio, and the self-weight with the additional superimposed load, corresponding to 60% of the yield strength of the unstrengthened beam and a deflection equal to the allowable deflection at the SLS. The influence of the longitudinal steel reinforcement ratio was also considered in this study. To reflect the variability seen in existing structures, test specimens were varied by using different steel bar diameters. Finally, the impact of the composite reinforcement ratio and the number of pretensioned FRP strips was considered. Specimens were divided into two series based on their strengthening configuration: series “A” were strengthened with one pretensioned and two non-pretensioned carbon FRP (CFRP strips, while series

  12. Ageing combines CD4 T cell lymphopenia in secondary lymphoid organs and T cell accumulation in gut associated lymphoid tissue.

    Science.gov (United States)

    Martinet, Kim Zita; Bloquet, Stéphane; Bourgeois, Christine

    2014-01-01

    CD4 T cell lymphopenia is an important T cell defect associated to ageing. Higher susceptibility to infections, cancer, or autoimmune pathologies described in aged individuals is thought to partly rely on T cell lymphopenia. We hypothesize that such diverse effects may reflect anatomical heterogeneity of age related T cell lymphopenia. Indeed, no data are currently available on the impact of ageing on T cell pool recovered from gut associated lymphoid tissue (GALT), a crucial site of CD4 T cell accumulation. Primary, secondary and tertiary lymphoid organs of C57BL/6 animals were analysed at three intervals of ages: 2 to 6 months (young), 10 to 14 months (middle-aged) and 22 to 26 months (old). We confirmed that ageing preferentially impacted CD4 T cell compartment in secondary lymphoid organs. Importantly, a different picture emerged from gut associated mucosal sites: during ageing, CD4 T cell accumulation was progressively developing in colon and small intestine lamina propria and Peyer's patches. Similar trend was also observed in middle-aged SJL/B6 F1 mice. Interestingly, an inverse correlation was detected between CD4 T cell numbers in secondary lymphoid organs and colonic lamina propria of C57BL/6 mice whereas no increase in proliferation rate of GALT CD4 T cells was detected. In contrast to GALT, no CD4 T cell accumulation was detected in lungs and liver in middle-aged animals. Finally, the concomitant accumulation of CD4 T cell in GALT and depletion in secondary lymphoid organs during ageing was detected both in male and female animals. Our data thus demonstrate that T cell lymphopenia in secondary lymphoid organs currently associated to ageing is not sustained in gut or lung mucosa associated lymphoid tissues or non-lymphoid sites such as the liver. The inverse correlation between CD4 T cell numbers in secondary lymphoid organs and colonic lamina propria and the absence of overt proliferation in GALT suggest that marked CD4 T cell decay in secondary

  13. AGE-modified basement membrane cooperates with Endo180 to promote epithelial cell invasiveness and decrease prostate cancer survival

    DEFF Research Database (Denmark)

    Rodriguez-Teja, Mercedes; Gronau, Julian H; Breit, Claudia

    2015-01-01

    Biomechanical strain imposed by age-related thickening of the basal lamina and augmented tissue stiffness in the prostate gland coincides with increased cancer risk. Here we hypothesized that the structural alterations in the basal lamina associated with age can induce mechanotransduction pathways...... in prostate epithelial cells (PECs) to promote invasiveness and cancer progression. To demonstrate this, we developed a 3D model of PEC acini in which thickening and stiffening of basal lamina matrix was induced by advanced glycation end-product (AGE)-dependent non-enzymatic crosslinking of its major......(Δ) (Ex2-6/) (Δ) (Ex2-6) mice, with constitutively exposed CTLD2 and decreased survival of men with early (non-invasive) prostate cancer with high epithelial Endo180 expression and levels of AGE. These findings indicate that AGE-dependent modification of the basal lamina induces invasive behaviour...

  14. Angled Growth of the Dental Lamina Is Accompanied by Asymmetrical Expression of the WNT Pathway Receptor Frizzled 6

    Czech Academy of Sciences Publication Activity Database

    Putnová, Iveta; Dosedělová, Hana; Bryja, V.; Landová, Marie; Buchtová, Marcela; Štembírek, Jan

    2017-01-01

    Roč. 8, č. 1 (2017), č. článku 29. ISSN 1664-042X R&D Projects: GA ČR(CZ) GP14-29273P Institutional support: RVO:67985904 Keywords : FZD6 * successional dental lamina * WNT signaling Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Developmental biology Impact factor: 4.134, year: 2016

  15. [Effectiveness of posterior intrasegmental fixation with pedicle screw-lamina hook system in treatment of lumbar spondylolysis].

    Science.gov (United States)

    Zhou, Zhongjie; Song, Yueming; Zeng, Jiancheng; Liu, Hao; Liu, Limin; Kong, Qingquan; Li, Tao; Gong, Quan

    2013-03-01

    To investigate the effectiveness of posterior intrasegmental fixation with pedicle screw-lamina hook system and bone grafting for lumbar spondylolysis. Between January 2005 and October 2009, 22 patients with lumbar spondylolysis underwent posterior intrasegmental fixation with pedicle screw-lamina hook system and bone grafting. There were 19 males and 3 females with an average age of 18.4 years (range, 12-26 years). The main symptom was low back pain with an average disease duration of 16 months (range, 8-56 months). The visual analogue scale (VAS) was 6.0 +/- 1.2 and Oswestry disability index (ODI) was 72.0% +/- 10.0% preoperatively. The X-ray films showed bilateral spondylolysis at L4 in 9 cases and at L5 in 13 cases. The range of motion (ROM) at upper and lower intervertebral spaces was (11.8 +/- 2.8) degrees and (14.1 +/- 1.9) degrees, respectively. All incisions healed by first intention. All patients were followed up 12-45 months (mean, 25 months). Low back pain was significantly alleviated after operation. The VAS score (0.3 +/- 0.5) and ODI (17.6% +/- 3.4%) were significantly decreased at last follow-up when compared with preoperative scores (P spondylolysis, having a high fusion rate, low complication rate, and maximum retention of lumbar ROM.

  16. Matrix expansion and syncytial aggregation of syndecan-1+ cells underpin villous atrophy in coeliac disease.

    Directory of Open Access Journals (Sweden)

    Camilla Salvestrini

    Full Text Available We studied the expression of sulphated glycosaminoglycans (GAGs in coeliac disease (CD mucosa, as they are critical determinants of tissue volume, which increases in active disease. We also examined mucosal expression of IL-6, which stimulates excess GAG synthesis in disorders such as Grave's ophthalmopathy.We stained archival jejunal biopsies from 5 children with CD at diagnosis, on gluten-free diet and challenge for sulphated GAGs. We then examined duodenal biopsies from 9 children with CD compared to 9 histological normal controls, staining for sulphated GAGs, heparan sulphate proteoglycans (HSPG, short-chain HSPG (Δ-HSPG and the proteoglycan syndecan-1 (CD138, which is expressed on epithelium and plasma cells. We confirmed findings with a second monoclonal in another 12 coeliac children. We determined mucosal IL-6 expression by immunohistochemistry and PCR in 9 further cases and controls, and used quantitative real time PCR for other Th17 pathway cytokines in an additional 10 cases and controls.In CD, HSPG expression was lost in the epithelial compartment but contrastingly maintained within an expanded lamina propria. Within the upper lamina propria, clusters of syndecan-1(+ plasma cells formed extensive syncytial sheets, comprising adherent plasma cells, lysed cells with punctate cytoplasmic staining and shed syndecan ectodomains. A dense infiltrate of IL-6(+ mononuclear cells was detected in active coeliac disease, also localised to the upper lamina propria, with significantly increased mRNA expression of IL-6 and IL-17A but not IL-23 p19.Matrix expansion, through syndecan-1(+ cell recruitment and lamina propria GAG increase, underpins villous atrophy in coeliac disease. The syndecan-1(+ cell syncytia and excess GAG production recapitulate elements of the invertebrate encapsulation reaction, itself dependent on insect transglutaminase and glutaminated early response proteins. As in other matrix expansion disorders, IL-6 is upregulated and

  17. Matrix Expansion and Syncytial Aggregation of Syndecan-1+ Cells Underpin Villous Atrophy in Coeliac Disease

    Science.gov (United States)

    Salvestrini, Camilla; Lucas, Mark; Lionetti, Paolo; Torrente, Franco; James, Sean; Phillips, Alan D.; Murch, Simon H.

    2014-01-01

    Background We studied the expression of sulphated glycosaminoglycans (GAGs) in coeliac disease (CD) mucosa, as they are critical determinants of tissue volume, which increases in active disease. We also examined mucosal expression of IL-6, which stimulates excess GAG synthesis in disorders such as Grave's ophthalmopathy. Methods We stained archival jejunal biopsies from 5 children with CD at diagnosis, on gluten-free diet and challenge for sulphated GAGs. We then examined duodenal biopsies from 9 children with CD compared to 9 histological normal controls, staining for sulphated GAGs, heparan sulphate proteoglycans (HSPG), short-chain HSPG (Δ-HSPG) and the proteoglycan syndecan-1 (CD138), which is expressed on epithelium and plasma cells. We confirmed findings with a second monoclonal in another 12 coeliac children. We determined mucosal IL-6 expression by immunohistochemistry and PCR in 9 further cases and controls, and used quantitative real time PCR for other Th17 pathway cytokines in an additional 10 cases and controls. Results In CD, HSPG expression was lost in the epithelial compartment but contrastingly maintained within an expanded lamina propria. Within the upper lamina propria, clusters of syndecan-1+ plasma cells formed extensive syncytial sheets, comprising adherent plasma cells, lysed cells with punctate cytoplasmic staining and shed syndecan ectodomains. A dense infiltrate of IL-6+ mononuclear cells was detected in active coeliac disease, also localised to the upper lamina propria, with significantly increased mRNA expression of IL-6 and IL-17A but not IL-23 p19. Conclusions Matrix expansion, through syndecan-1+ cell recruitment and lamina propria GAG increase, underpins villous atrophy in coeliac disease. The syndecan-1+ cell syncytia and excess GAG production recapitulate elements of the invertebrate encapsulation reaction, itself dependent on insect transglutaminase and glutaminated early response proteins. As in other matrix expansion disorders

  18. Cellular Evidence of Telocytes as Novel Interstitial Cells Within the Magnum of Chicken Oviduct.

    Science.gov (United States)

    Yang, Ping; Zhu, Xudong; Wang, Lingling; Ahmed, Nisar; Huang, Yufei; Chen, Hong; Zhang, Qian; Ullah, Shakeeb; Liu, Tengfei; Guo, Dawei; Brohi, Sarfaraz Ahmed; Chen, Qiusheng

    2017-01-24

    Telocytes are a novel type of interstitial cell that has been identified in many organs of mammals, but there is little information available on these cells in avian species. This study shows the latest findings associated with telocytes in the muscular layer and lamina propria of the magnum of chicken oviduct analyzed by transmission electron microscopy. Telocytes are characterized by telopodes, which are thin and long prolongations, and a small amount of cytoplasm rich with mitochondria. Spindle- or triangular-shaped telocytes were detected at various locations in the magnum. In the muscular layer, telocytes have direct connection with smooth muscle cells. The cell body of telocytes along with their long telopodes mainly exists in the interstitial space between the smooth muscle bundles, whereas large numbers of short telopodes are scattered in between the smooth muscle cells. In the lamina propria, extremely long telopodes are twisting around each other and are usually collagen embedded. Both in the lamina propria and muscular layer, telocytes have a close relationship with other cell types, such as immune cells and blood vessels. Telopodes appear with dichotomous branching alternating between the podom and podomer, forming a 3D network structure with complex homo- and heterocellular junctions. In addition, a distinctive size of the vesicles is visible around the telopodes and may be released from telopodes because of the close relation between the vesicle and telopode. All characteristics of telocytes in the magnum indicate that telocytes may play a potential, but important, role in the pathogenesis of oviduct diseases.

  19. Pacemaker cells in the gastrointestinal tract

    DEFF Research Database (Denmark)

    Rumessen, J J; Thuneberg, L

    1996-01-01

    Interstitial cells of Cajal (ICC) were described a century ago as primitive neurons in the intestines. Through the years, ICC have been mistaken for neurons, glial cells, fibroblasts, smooth muscle cells, and macrophages. We identified ICC in the musculature of mouse small intestine...... patterns; characteristic patterns of contact with smooth muscle cells) and ultrastructure (myoid features: basal lamina, caveolae, rich in sER and mitochondria, often prominent filament bundles and dense bands/bodies) has allowed the identification of ICC in the GI musculature of all species investigated...

  20. Dendritic cells in Barrett's esophagus and esophageal adenocarcinoma.

    Science.gov (United States)

    Bobryshev, Yuri V; Tran, Dinh; Killingsworth, Murray C; Buckland, Michael; Lord, Reginald V N

    2009-01-01

    Like other premalignant conditions that develop in the presence of chronic inflammation, the development and progression of Barrett's esophagus is associated with the development of an immune response, but how this immune response is regulated is poorly understood. A comprehensive literature search failed to find any report of the presence of dendritic cells in Barrett's intestinal metaplasia and esophageal adenocarcinoma and this prompted our study. We used immunohistochemical staining and electron microscopy to examine whether dendritic cells are present in Barrett's esophagus and esophageal adenocarcinoma. Immunohistochemical staining with CD83, a specific marker for dendritic cells, was performed on paraffin-embedded sections of Barrett's intestinal metaplasia (IM, n = 12), dysplasia (n = 11) and adenocarcinoma (n = 14). CD83+ cells were identified in the lamina propria surrounding intestinal type glands in Barrett's IM, dysplasia, and cancer tissues. Computerized quantitative analysis showed that the numbers of dendritic cells were significantly higher in cancer tissues. Double immunostaining with CD83, CD20, and CD3, and electron microscopy demonstrated that dendritic cells are present in Barrett's esophagus and form clusters with T cells and B cells directly within the lamina propria. These findings demonstrate that dendritic cells are present in Barrett's tissues, with a significant increase in density in adenocarcinoma compared to benign Barrett's esophagus. Dendritic cells may have a role in the pathogenesis and immunotherapy treatment of Barrett's esophagus and adenocarcinoma.

  1. Digital radiographic evaluation of alveolar bone loss, density and lamina dura integrity on post splinting mandibular anterior with chronic periodontitis

    Science.gov (United States)

    Rafini, F.; Priaminiarti, M.; Sukardi, I.; Lessang, R.

    2017-08-01

    The healing of periodontal splinting can be detected both with clinical and radiographic examination. In this study, the alveolar bone was evaluated by radiographic digital periapical analysis. Periodontal tooth splinting is periodontal support therapy used to prevent periodontal injury during repair and regeneration of periodontal therapy. Radiographic digital periapical analysis of alveolar bone in the mandibular anterior region with chronic periodontitis and 2/3 cervical bone loss after three months of periodontal splinting. Eighty four proximal site (43 mesial and 41 distal) from 16 patients with chronic periodontitis and treated with spinting were examined by taking periapical digital radiographic at day 1 and 91. The bone loss, bone density and utility of lamina dura were evaluated. The statistical analysis after three months evaluation using T-test for bone loss, Wilcoxon sign rank test for bone density and utility lamina dura showed no significantly differences (pchronic periodontitis with 2/3 alveolar bone loss after three months splinting.

  2. Immunoglobulin leakiness in scid mice with CD4(+) T-cell-induced chronic colitis

    DEFF Research Database (Denmark)

    Brimnes, J; Reimann, J; Claesson, Mogens Helweg

    2000-01-01

    Inflammatory bowel disease in scid mice is initiated by transplantation of CD4(+) T-cells from immunocompetent syngenic donor mice. As the disease progresses, immunoglobulin (Ig)-containing cells appear in the gut lamina propria, suggesting that locally accumulating Ig may play a role in disease ...

  3. Estimate of compressive strength of an unidirectional composite lamina using cross-ply and angle-ply laminates

    OpenAIRE

    Scafè, M.; Raiteri, G.; Brentari, A.; Dlacic, R.; Troiani, E.; Falaschetti, M. P.; Besseghini, E.

    2014-01-01

    In this work has been estimated the compressive strength of a unidirectional lamina of a carbon/epoxy composite material, using the cross-ply and angle-ply laminates. Over the years various methods have been developed to deduce compressive properties of composite materials reinforced with long fibres. Each of these methods is characterized by a specific way of applying load to the specimen. The method chosen to perform the compression tests is the Wyoming Combined Loading Compr...

  4. Sensitization to epithelial antigens in chronic mucosal inflammatory disease. Characterization of human intestinal mucosa-derived mononuclear cells reactive with purified epithelial cell-associated components in vitro.

    OpenAIRE

    Roche, J K; Fiocchi, C; Youngman, K

    1985-01-01

    To explore the auto-reactive potential of cells infiltrating the gut mucosa in idiopathic chronic inflammatory bowel disease, intestinal lamina propria mononuclear cells (LPMC) were isolated, characterized morphologically and phenotypically, and evaluated for antigen-specific reactivity. The last was assessed by quantitating LPMC cytotoxic capabilities against purified, aqueous-soluble, organ-specific epithelial cell-associated components (ECAC) characterized previously. Enzyme-isolated infla...

  5. Mesoscopic Strains Maps in Woven Composite Laminas During Off-axis Tension

    Directory of Open Access Journals (Sweden)

    Nicoletto G.

    2010-06-01

    Full Text Available The mechanics of woven carbon-fiber reinforced plastic (CFRP composites is influenced by the complex architecture of the reinforcement phase. Computational (i.e. finite element based approaches have been used increasingly to model not only the global laminate stiffness, but also damage evolution and laminate strength. The modeling combines the identification of the architectural unit cell (UC, the selection of suitable constitutive models of the different phases, the creation of a fine discretization of the UC in finite elements, the application of an incremental solution procedure that solves iteratively for the stresses and strains in the UC, [1]. The experimental validation of computational models is carried out mainly at the macroscopical level, i.e. simulation of the macroscopic stress-strain curve. Damage, however, is a localized, straindependent phenomenon and therefore only accurate strain distribution within the UC (at the mesolevel can identify critical conditions in terms of damage location, extension and evolution. The validation of computational damage procedures is a key task and full-field optical strain analysis methods appear the ideal instrument. However, only limited examples of direct finte element method (FEM vs experimental strain correlation are found because of the limited sensitivity and spatial resolution of some techniques and the complexity and applicative difficulty of others. The aim of the present paper is to present the application of the digital image correlation (DIC technique, [2], to the full-field strain analysis at the mesoscopic level (i.e. within the UC of a woven CFRP lamina when the direction of loading forms an angle to the material direction. The material under consideration is a woven carbon fiber reinforced epoxy composite. Orthogonal yarns, each made of of several thousand fibers, are woven according the twill-weave architecture is shown in Fig. 1a. Single-ply laminas were manufactured and tested to

  6. Transforming growth factor beta 1 modulates extracellular matrix organization and cell-cell junctional complex formation during in vitro angiogenesis.

    Science.gov (United States)

    Merwin, J R; Anderson, J M; Kocher, O; Van Itallie, C M; Madri, J A

    1990-01-01

    Transforming growth factor-beta 1 (TGF-beta 1) is angiogenic in vivo. In two-dimensional (2-D) culture systems microvascular endothelial cell proliferation is inhibited up to 80% by TGF-beta 1; however, in three-dimensional (3-D) collagen gels TGF-beta 1 is found to have no effect on proliferation while eliciting the formation of calcium and magnesium dependent tube-like structures mimicking angiogenesis. DNA analyses performed on 3-D cell cultures reveal no significant difference in the amount of DNA or cell number in control versus TGF-beta 1 treated cultures. In 2-D cultures TGF-beta 1 is known to increase cellular fibronectin accumulation; however, in 3-D cultures no difference is seen between control and TGF-beta 1 treated cells as established by ELISA testing for type IV collagen, fibronectin, and laminin. In 3-D cultures there is increased synthesis and secretion of type V collagen in both control and TGF-beta 1 treated cultures over 2-D cultures. Even though an equal amount of type V collagen is seen in both 3-D conditions, there is a reorganization of the protein with concentration along an organizing basal lamina in TGF-beta 1 treated cultures. EM morphological analyses on 3-D cultures illustrate quiescent, control cells lacking cell contacts. In contrast, TGF-beta 1 treated cells show increased pseudopod formation, cell-cell contact, and organized basal lamina-like material closely apposed to the "abluminal" plasma membranes. TGF-beta 1 treated cells also appear to form junctional complexes between adjoining cells. Immunofluorescence using specific antibodies to the tight junction protein ZO-1 results in staining at apparent cell-cell junctions in the 3-D cultures. Northern blots of freshly isolated microvascular endothelium, 2-D and 3-D cultures, using cDNA and cRNA probes specific for the ZO-1 tight junction protein, reveal the presence of the 7.8 kb mRNA. Western blots of rat epididymal fat pad endothelial cells (RFC) monolayer lysates probed with

  7. The pulmonary pseudonodule: Characteristic features of a normal variant due to a bone thickening at the junction of the laminae and posterior spine

    International Nuclear Information System (INIS)

    Homer, M.J.

    1981-01-01

    The normal thickening of bone at the junction of the laminae and posterior spine should not be confused with a patholigc process. Its appearance on the plain radiograph and computed tomography is pathognomonic. (orig.)

  8. Mechanical response and buckling of a polymer simulation model of the cell nucleus

    Science.gov (United States)

    Banigan, Edward; Stephens, Andrew; Marko, John

    The cell nucleus must robustly resist extra- and intracellular forces to maintain genome architecture. Micromanipulation experiments measuring nuclear mechanical response reveal that the nucleus has two force response regimes: a linear short-extension response due to the chromatin interior and a stiffer long-extension response from lamin A, comprising the intermediate filament protein shell. To explain these results, we developed a quantitative simulation model with realistic parameters for chromatin and the lamina. Our model predicts that crosslinking between chromatin and the lamina is essential for responding to small strains and that changes to the interior topological organization can alter the mechanical response of the whole nucleus. Thus, chromatin polymer elasticity, not osmotic pressure, is the dominant regulator of this force response. Our model reveals a novel buckling transition for polymer shells: as force increases, the shell buckles transverse to the applied force. This transition, which arises from topological constrains in the lamina, can be mitigated by tuning the properties of the chromatin interior. Thus, we find that the genome is a resistive mechanical element that can be tuned by its organization and connectivity to the lamina.

  9. Mast cell-derived histamine mediates cystitis pain.

    Directory of Open Access Journals (Sweden)

    Charles N Rudick

    2008-05-01

    Full Text Available Mast cells trigger inflammation that is associated with local pain, but the mechanisms mediating pain are unclear. Interstitial cystitis (IC is a bladder disease that causes debilitating pelvic pain of unknown origin and without consistent inflammation, but IC symptoms correlate with elevated bladder lamina propria mast cell counts. We hypothesized that mast cells mediate pelvic pain directly and examined pain behavior using a murine model that recapitulates key aspects of IC.Infection of mice with pseudorabies virus (PRV induces a neurogenic cystitis associated with lamina propria mast cell accumulation dependent upon tumor necrosis factor alpha (TNF, TNF-mediated bladder barrier dysfunction, and pelvic pain behavior, but the molecular basis for pelvic pain is unknown. In this study, both PRV-induced pelvic pain and bladder pathophysiology were abrogated in mast cell-deficient mice but were restored by reconstitution with wild type bone marrow. Pelvic pain developed normally in TNF- and TNF receptor-deficient mice, while bladder pathophysiology was abrogated. Conversely, genetic or pharmacologic disruption of histamine receptor H1R or H2R attenuated pelvic pain without altering pathophysiology.These data demonstrate that mast cells promote cystitis pain and bladder pathophysiology through the separable actions of histamine and TNF, respectively. Therefore, pain is independent of pathology and inflammation, and histamine receptors represent direct therapeutic targets for pain in IC and other chronic pain conditions.

  10. Nuclear lamina and nuclear matrix organization in sperm pronuclei assembled in Xenopus egg extract.

    Science.gov (United States)

    Zhang, C; Jenkins, H; Goldberg, M W; Allen, T D; Hutchison, C J

    1996-09-01

    Nuclear lamina and matrices were prepared from sperm pronuclei assembled in Xenopus egg extracts using a fractionation and extraction procedure. Indirect immunofluorescence revealed that while chromatin was efficiently removed from nuclei during the extraction procedure, the distribution of lamins was unaffected. Consistent with this data, the amount of lamin B3, determined by immunoblotting, was not affected through the extraction procedure. Nuclear matrices were visualised in DGD sections by TEM. Within these sections filaments were observed both at the boundary of the nucleus (the lamina) and within the body of the nucleus (internal nuclear matrix filaments). To improve resolution, nuclear matrices were also prepared as whole mounts and viewed using field emission in lens scanning electron microscopy (FEISEM). This technique revealed two distinct networks of filaments. Filaments lying at the surface of nuclear matrices interconnected nuclear pores. These filaments were readily labelled with monoclonal anti-lamin B3 antibodies. Filaments lying within the body of the nuclear matrix were highly branched but were not readily labelled with antilamin B3 antibodies. Nuclear matrices were also prepared from sperm pronuclei assembled in lamin B3 depleted extracts. Using FEISEM, filaments were also detected in these preparations. However, these filaments were poorly organised and often appeared to aggregate. To confirm these results nuclear matrices were also observed as whole mounts using TEM. Nuclear matrices prepared from control nuclei contained a dense array of interconnected filaments. Many (but not all) of these filaments were labelled with anti-lamin B3 antibodies. In contrast, nuclear matrices prepared from "lamin depleted nuclei' contained poorly organised or aggregated filaments which were not specifically labelled with anti-lamin B3 antibodies.

  11. Oral administration of kefiran induces changes in the balance of immune cells in a murine model.

    Science.gov (United States)

    Medrano, Micaela; Racedo, Silvia M; Rolny, Ivanna S; Abraham, Analía G; Pérez, Pablo F

    2011-05-25

    The aim of the present study was to evaluate the effect of the oral administration of kefiran on the balance of immune cells in a murine model. Six week old BALB/c mice were treated with kefiran (300 mg/L) for 0, 2 and 7 days. Kefiran treatment increased the number of IgA+ cells in lamina propria after 2 and 7 days. Percentage of B220+/MHCII(high) cells in mesenteric lymph nodes (2 days) and Peyer's patches (7 days) was higher compared to untreated control mice. An increase of macrophages (F4/80+ cells) was observed in lamina propria and peritoneal cavity (2 and 7 days). In contrast, at day 7, macrophage population decreased in Peyer's patches. These results show the ability of kefiran to modify the balance of immune cells in intestinal mucosa. This property could be highly relevant for the comprehension of the probiotic effect attributed to kefir.

  12. Foot muscles strengthener

    Directory of Open Access Journals (Sweden)

    Boris T. Glavač

    2012-04-01

    Full Text Available Previous experience in the correction of flat feet consisted of the use of insoles for shoes and exercises with toys, balls, rollers, inclined planes, etc. A device for strengthening foot muscles is designed for the correction of flat feet in children and, as its name suggests, for strengthening foot muscles in adults. The device is made of wood and metal, with a mechanism and technical solutions, enabling the implementation of specific exercises to activate muscles responsible for the formation of the foot arch. It is suitable for home use with controlled load quantities since it has calibrated springs. The device is patented with the Intellectual Property Office, Republic of Serbia, as a petty patent.

  13. Oxide dispersion-strengthened ferritic alloys

    International Nuclear Information System (INIS)

    Asbroeck, P. van.

    1976-10-01

    The publication gives the available data on the DTO2 dispersion-strengthened ferritic alloy developed at C.E.N./S.C.K. Mol, Belgium. DTO2 is a Fe-Cr-Mo ferritic alloy, strengthened by addition of titanium oxide and of titanium leading to the formation of Chi phase. It was developed for use as canning material for fast breeder reactors. (author)

  14. Small Intestinal Submucosa Implantation for the Possible Treatment of Vocal Fold Scar, Sulcus, and Superficial Lamina Propria Atrophy.

    Science.gov (United States)

    Pitman, Michael J; Cabin, Jonathan A; Iacob, Codrin E

    2016-02-01

    Evaluate the histologic effects of grafting porcine-derived small intestinal submucosa (SIS) into the vocal fold superficial lamina propria (SLP) layer for the potential treatment of vocal fold scar, sulcus and superficial lamina propria atrophy. Small intestinal submucosa was implanted into the right vocal fold SLP of 6 mongrel dogs. The left vocal fold served as a sham surgical control. At 2, 4, and 6 weeks postoperative, bilateral vocal fold specimens were evaluated histologically. At 2 and 4 weeks, respectively, SIS-implanted vocal folds demonstrated moderate and mild inflammation and acute and chronic inflammation. At 6 weeks, inflammation was minimal and chronic. The 6-week specimens showed copious amounts of newly generated hyaluronic acid (HA) within the graft. There was no reactive fibrosis at 6 weeks. In the canine model, SIS appears safe for SLP grafting. Inflammation is similar to that of sham surgery. Small intestinal submucosa results in newly generated HA without concomitant fibrosis. Small intestinal submucosa has potential to be used in treatment of disorders with SLP, including vocal fold scar, sulcus, and atrophy. Studies evaluating the effect of SIS implantation on vocal fold function, as well as the ultimate fate of the graft, are required. © The Author(s) 2015.

  15. Rapid method for culturing embryonic neuron-glial cell cocultures

    DEFF Research Database (Denmark)

    Svenningsen, Åsa Fex; Shan, Wei-Song; Colman, David R

    2003-01-01

    neurons is seen after 3 weeks (2 weeks in ascorbic acid), suggesting that basal lamina production is important even for glial ensheathment in the enteric nervous system. No overgrowth of fibroblasts or other nonneuronal cells was noted in any cultures, and myelination of the peripheral nervous system...

  16. Lamina Cribrosa Changes after Laser In Situ Keratomileusis in Myopic Eyes.

    Science.gov (United States)

    Lee, Soomin; Choi, Da Ye Diana; Lim, Dong Hui; Chung, Tae Young; Han, Jong Chul; Kee, Changwon

    2018-04-01

    To determine deep optic nerve head structure changes after transient intraocular pressure elevation during laser in situ keratomileusis (LASIK) for myopia. Enhanced depth imaging-optical coherence tomography was performed in each myopic eye that underwent LASIK surgery. Enhanced depth imaging-optical coherence tomography images were created at postoperative 1 day, 1 week, 2 weeks, and 1 month. Lamina cribrosa (LC) thickness, LC depth and prelaminar thickness at the superior, middle and inferior portions of the optic nerve head were measured by two investigators. Forty eyes in 40 patients were included in the present study. During follow-up, there were no significant differences in prelaminar thickness or LC depth. The LC demonstrated increased thickness at postoperative 1 day at all three locations (superior, middle, and inferior) (p LASIK surgery. However, the thickness will gradually return to baseline morphology. Temporary intraocular pressure increase during LASIK does not appear to induce irreversible LC thickness changes. © 2018 The Korean Ophthalmological Society.

  17. HIV communication capacity strengthening: a critical review.

    Science.gov (United States)

    Lettenmaier, Cheryl; Kraft, Joan Marie; Raisanen, Keris; Serlemitsos, Elizabeth

    2014-08-15

    HIV communication is most effective and sustainable when it is designed and implemented locally and tailored to the local context. This requires capacity strengthening at national, subnational, and community levels. Through a review of the published and selected "grey" literature, we examine HIV communication capacity strengthening: definitions, measurements, implementation, and effects. We found limited documentation of HIV communication capacity needs or systematic approaches to address them. Most HIV communication capacity strengthening to date has focused on building individual competencies to design and manage social and behavior change communication programs through training courses, often coupled with networking opportunities for participants, post-training mentoring, and technical assistance. A few of these efforts have been evaluated through pre- and post-training tests and qualitative interviews with participants and have shown potential for improvement in individual skills and knowledge. Health communication capacity assessment tools that measure individual and organizational competencies exist, but they have most often been used to identify capacity building needs, not for evaluating capacity strengthening efforts. A new definition of capacity strengthening, grown out of recent efforts to improve effectiveness of international health and development programs, focuses on improving organizational and societal systems that support performance and individual competencies. We propose a holistic model for HIV communication capacity strengthening and call for rigorous documentation and evaluation to determine and scale-up optimal capacity building interventions for strengthening social and behavior change communication for HIV prevention, care, and treatment in developing countries.

  18. Regeneration of Vocal Fold Mucosa Using Tissue-Engineered Structures with Oral Mucosal Cells

    Science.gov (United States)

    Fukahori, Mioko; Chitose, Shun-ichi; Sato, Kiminori; Sueyoshi, Shintaro; Kurita, Takashi; Umeno, Hirohito; Monden, Yu; Yamakawa, Ryoji

    2016-01-01

    Objectives Scarred vocal folds result in irregular vibrations during phonation due to stiffness of the vocal fold mucosa. To date, a completely satisfactory corrective procedure has yet to be achieved. We hypothesize that a potential treatment option for this disease is to replace scarred vocal folds with organotypic mucosa. The purpose of this study is to regenerate vocal fold mucosa using a tissue-engineered structure with autologous oral mucosal cells. Study Design Animal experiment using eight beagles (including three controls). Methods A 3 mm by 3 mm specimen of canine oral mucosa was surgically excised and divided into epithelial and subepithelial tissues. Epithelial cells and fibroblasts were isolated and cultured separately. The proliferated epithelial cells were co-cultured on oriented collagen gels containing the proliferated fibroblasts for an additional two weeks. The organotypic cultured tissues were transplanted to the mucosa-deficient vocal folds. Two months after transplantation, vocal fold vibrations and morphological characteristics were observed. Results A tissue-engineered vocal fold mucosa, consisting of stratified epithelium and lamina propria, was successfully fabricated to closely resemble the normal layered vocal fold mucosa. Laryngeal stroboscopy revealed regular but slightly small mucosal waves at the transplanted site. Immunohistochemically, stratified epithelium expressed cytokeratin, and the distributed cells in the lamina propria expressed vimentin. Elastic Van Gieson staining revealed a decreased number of elastic fibers in the lamina propria of the transplanted site. Conclusion The fabricated mucosa with autologous oral mucosal cells successfully restored the vocal fold mucosa. This reconstruction technique could offer substantial clinical advantages for treating intractable diseases such as scarring of the vocal folds. PMID:26730600

  19. Spatial distribution of diffuse, primitive, and classic amyloid-beta deposits and blood vessels in the upper laminae of the frontal cortex in Alzheimer disease.

    Science.gov (United States)

    Armstrong, R A; Cairns, N J; Lantos, P L

    1998-12-01

    The spatial distribution of the diffuse, primitive, and classic amyloid-beta deposits was studied in the upper laminae of the superior frontal gyrus in cases of sporadic Alzheimer disease (AD). Amyloid-beta-stained tissue was counterstained with collagen IV to determine whether the spatial distribution of the amyloid-beta deposits along the cortex was related to blood vessels. In all patients, amyloid-beta deposits and blood vessels were aggregated into distinct clusters and in many patients, the clusters were distributed with a regular periodicity along the cortex. The clusters of diffuse and primitive deposits did not coincide with the clusters of blood vessels in most patients. However, the clusters of classic amyloid-beta deposits coincided with those of the large diameter (>10 microm) blood vessels in all patients and with clusters of small-diameter (upper cortical laminae.

  20. A-type and B-type lamins initiate layer assembly at distinct areas of the nuclear envelope in living cells

    Energy Technology Data Exchange (ETDEWEB)

    Furukawa, Kazuhiro, E-mail: furukawa@chem.sc.niigata-u.ac.jp [Department of Chemistry, Faculty of Science, Niigata University, Niigata 950-2181 (Japan); Ishida, Kazuya; Tsunoyama, Taka-aki; Toda, Suguru; Osoda, Shinichi; Horigome, Tsuneyoshi [Department of Chemistry, Faculty of Science, Niigata University, Niigata 950-2181 (Japan); Fisher, Paul A. [Department of Pharmacological Sciences, School of Medicine, University Medical Center, State University of New York at Stony Brook, Stony Brook, NY 11794-8651 (United States); Sugiyama, Shin [Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya 464-8602 (Japan)

    2009-04-15

    To investigate nuclear lamina re-assembly in vivo, Drosophila A-type and B-type lamins were artificially expressed in Drosophila lamin Dm{sub 0}null mutant brain cells. Both exogenous lamin C (A-type) and Dm{sub 0} (B-type) formed sub-layers at the nuclear periphery, and efficiently reverted the abnormal clustering of the NPC. Lamin C initially appeared where NPCs were clustered, and subsequently extended along the nuclear periphery accompanied by the recovery of the regular distribution of NPCs. In contrast, lamin Dm{sub 0} did not show association with the clustered NPCs during lamina formation and NPC spacing recovered only after completion of a closed lamin Dm{sub 0} layer. Further, when lamin Dm{sub 0} and C were both expressed, they did not co-polymerize, initiating layer formation in separate regions. Thus, A and B-type lamins reveal differing properties during lamina assembly, with A-type having the primary role in organizing NPC distribution. This previously unknown complexity in the assembly of the nuclear lamina could be the basis for intricate nuclear envelope functions.

  1. MHC class II+ (HLA-DP-like) cells in the cow reproductive tract: II. Immunolocalization of MHC class II+ cells in oviduct and vagina.

    Science.gov (United States)

    Eren, U; Kum, S; Sandikçi, M; Eren, V; Ilhan, F

    2009-08-01

    The aim of this study was to determine and examine the distribution of major frequency MHC II+ cells in the oviduct and vagina of cows during the oestrous and dioestrus phases. Right oviduct (ampulla, isthmus) and vaginal samples taken from a total of twenty seven multiparous cows were used. Tissue samples were processed to obtain both cryostat and paraffin sections. Sections were stained immunocytochemically using StreptABC method using a specific monoclonal antibody to MHC II+ cell population. Intra-epithelial and subepithelial areas along with lamina propria, muscularis mucosae and serosa of both ampulla and isthmus and intra-epithelial/subepithelial areas and mucosae of vagina were examined for the presence of MHC II+ cells. The density of immune positive cells was determined using a subjective scoring system. MHC II+ cells were demonstrated in all areas examined in both oestrus and dioestrus. In oestrus, the density of MHC II+ cells decreased in subepithelial areas (in between the epithelial cells and the basal membrane) of isthmus, whereas the density of immune positive cells was increased in muscularis mucosae of isthmus (P < 0.05), lamina propria and muscularis mucosae of ampulla (P < 0.05) as well as in the mucosae of vagina (P cells observed in the oviduct and vagina increases in the majority of areas examined due to the effect of oestrogen.

  2. Strengthening CRTD-A's Organizational and Program Capacity ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Strengthening CRTD-A's Organizational and Program Capacity (Lebanon) ... Women's Rights and Citizenship framework; to strengthen and rationalize its institutional ... IDRC “unpacks women's empowerment” at McGill University Conference.

  3. Strengthening of RC bridge slabs using CFRP sheets

    Directory of Open Access Journals (Sweden)

    Fahmy A. Fathelbab

    2014-12-01

    Full Text Available Many old structures became structurally insufficient to carry the new loading conditions requirements. Moreover, they suffer from structural degradation, reinforcement steel bars corrosion, bad weather conditions…etc. Many official authorities in several countries had recognized many old bridges and buildings as structurally deficient by today’s standards. Due to these reasons, structural strengthening became an essential requirement and different strengthening techniques appeared in market. Fiber Reinforced Polymer (FRP strengthening techniques established a good position among all other techniques, giving excellent structural results, low time required and moderate cost compared with the other techniques. The main purpose of this research is to study analytically the strengthening of a reinforced concrete bridge slabs due to excessive loads, using externally bonded FRP sheets technique. A commercial finite element program ANSYS was used to perform a structural linear and non-linear analysis for strengthened slab models using several schemes of FRP sheets. A parametric study was performed to evaluate analytically the effect of changing both FRP stiffness and FRP schemes in strengthening RC slabs. Comparing the results with control slab (reinforced concrete slab without strengthening it is obvious that attaching FRP sheets to the RC slab increases its capacity and enhances the ductility/toughness.

  4. Visualizing the molecular sociology at the HeLa cell nuclear periphery.

    Science.gov (United States)

    Mahamid, Julia; Pfeffer, Stefan; Schaffer, Miroslava; Villa, Elizabeth; Danev, Radostin; Cuellar, Luis Kuhn; Förster, Friedrich; Hyman, Anthony A; Plitzko, Jürgen M; Baumeister, Wolfgang

    2016-02-26

    The molecular organization of eukaryotic nuclear volumes remains largely unexplored. Here we combined recent developments in cryo-electron tomography (cryo-ET) to produce three-dimensional snapshots of the HeLa cell nuclear periphery. Subtomogram averaging and classification of ribosomes revealed the native structure and organization of the cytoplasmic translation machinery. Analysis of a large dynamic structure-the nuclear pore complex-revealed variations detectable at the level of individual complexes. Cryo-ET was used to visualize previously elusive structures, such as nucleosome chains and the filaments of the nuclear lamina, in situ. Elucidation of the lamina structure provides insight into its contribution to metazoan nuclear stiffness. Copyright © 2016, American Association for the Advancement of Science.

  5. Nuclear protein import is reduced in cells expressing nuclear envelopathy-causing lamin A mutants

    International Nuclear Information System (INIS)

    Busch, Albert; Kiel, Tilman; Heupel, Wolfgang-M.; Wehnert, Manfred; Huebner, Stefan

    2009-01-01

    Lamins, which form the nuclear lamina, not only constitute an important determinant of nuclear architecture, but additionally play essential roles in many nuclear functions. Mutations in A-type lamins cause a wide range of human genetic disorders (laminopathies). The importance of lamin A (LaA) in the spatial arrangement of nuclear pore complexes (NPCs) prompted us to study the role of LaA mutants in nuclear protein transport. Two mutants, causing prenatal skin disease restrictive dermopathy (RD) and the premature aging disease Hutchinson Gilford progeria syndrome, were used for expression in HeLa cells to investigate their impact on the subcellular localization of NPC-associated proteins and nuclear protein import. Furthermore, dynamics of the LaA mutants within the nuclear lamina were studied. We observed affected localization of NPC-associated proteins, diminished lamina dynamics for both LaA mutants and reduced nuclear import of representative cargo molecules. Intriguingly, both LaA mutants displayed similar effects on nuclear morphology and functions, despite their differences in disease severity. Reduced nuclear protein import was also seen in RD fibroblasts and impaired lamina dynamics for the nucleoporin Nup153. Our data thus represent the first study of a direct link between LaA mutant expression and reduced nuclear protein import.

  6. Lamina cribrosa position and Bruch's membrane opening differences between anterior ischemic optic neuropathy and open-angle glaucoma.

    Science.gov (United States)

    Rebolleda, Gema; Pérez-Sarriegui, Ane; Díez-Álvarez, Laura; De Juan, Victoria; Muñoz-Negrete, Francisco J

    2018-06-01

    To compare the optic nerve head morphology among primary open-angle glaucoma, non-arteritic anterior ischemic optic neuropathy eyes, their fellow healthy eyes and control eyes, using spectral-domain optical coherence tomography with enhanced depth imaging. Observational cross-sectional study including 88 eyes of 68 patients. In this study, 23 non-arteritic anterior ischemic optic neuropathy eyes, 17 fellow unaffected eyes, 25 primary open-angle glaucoma eyes, and 23 age-matched control eyes were included. Peripapillary retinal nerve fiber layer thickness and optic disk area were evaluated. Bruch's membrane opening diameter, optic cup depth, anterior lamina cribrosa depth, and prelaminar tissue thickness were assessed. Non-arteritic anterior ischemic optic neuropathy and primary open-angle glaucoma eyes had similar visual field mean deviation and peripapillary retinal nerve fiber layer thickness (P = 0.6 and P = 0.56, respectively). Bruch's membrane opening diameter was significantly larger in primary open-angle glaucoma eyes than in control eyes (P = 0.02). Lamina cribrosa and disk cup were deeper in eyes with primary open-angle glaucoma than both control and non-arteritic anterior ischemic optic neuropathy eyes (P open-angle glaucoma eyes than in non-arteritic anterior ischemic optic neuropathy eyes (P opening diameter was found in primary open-angle glaucoma eyes compared with control eyes. This issue has clinical implications because Bruch's membrane opening has been considered a stable reference for disk-related measures.

  7. Numerical Investigation of Masonry Strengthened with Composites

    Directory of Open Access Journals (Sweden)

    Giancarlo Ramaglia

    2018-03-01

    Full Text Available In this work, two main fiber strengthening systems typically applied in masonry structures have been investigated: composites made of basalt and hemp fibers, coupled with inorganic matrix. Starting from the experimental results on composites, the out-of-plane behavior of the strengthened masonry was assessed according to several numerical analyses. In a first step, the ultimate behavior was assessed in terms of P (axial load-M (bending moment domain (i.e., failure surface, changing several mechanical parameters. In order to assess the ductility capacity of the strengthened masonry elements, the P-M domain was estimated starting from the bending moment-curvature diagrams. Key information about the impact of several mechanical parameters on both the capacity and the ductility was considered. Furthermore, the numerical analyses allow the assessment of the efficiency of the strengthening system, changing the main mechanical properties. Basalt fibers had lower efficiency when applied to weak masonry. In this case, the elastic properties of the masonry did not influence the structural behavior under a no tension assumption for the masonry. Conversely, their impact became non-negligible, especially for higher values of the compressive strength of the masonry. The stress-strain curve used to model the composite impacted the flexural strength. Natural fibers provided similar outcomes, but a first difference regards the higher mechanical compatibility of the strengthening system with the substrate. In this case, the ultimate condition is due to the failure mode of the composite. The stress-strain curves used to model the strengthening system are crucial in the ductility estimation of the strengthened masonry. However, the behavior of the composite strongly influences the curvature ductility in the case of higher compressive strength for masonry. The numerical results discussed in this paper provide the base to develop normalized capacity models able to

  8. Sleep On It: How Snoozing Strengthens Memories

    Science.gov (United States)

    ... Special Issues Subscribe April 2013 Print this issue Sleep On It How Snoozing Strengthens Memories Send us ... the best way to remember it is to sleep on it. That’s because sleeping helps strengthen memories ...

  9. Immunostaining for Homer reveals the majority of excitatory synapses in laminae I?III of the mouse spinal dorsal horn

    OpenAIRE

    Gutierrez-Mecinas, Maria; Kuehn, Emily D.; Abraira, Victoria E.; Polg?r, Erika; Watanabe, Masahiko; Todd, Andrew J.

    2016-01-01

    The spinal dorsal horn processes somatosensory information before conveying it to the brain. The neuronal organization of the dorsal horn is still poorly understood, although recent studies have defined several distinct populations among the interneurons, which account for most of its constituent neurons. All primary afferents, and the great majority of neurons in laminae I–III are glutamatergic, and a major factor limiting our understanding of the synaptic circuitry has been the difficulty i...

  10. Low-Cost Intra-Articular Distraction Technique Using Kirschner Wires and a Toothed Lamina Spreader.

    Science.gov (United States)

    Shymon, Stephen Joseph; Harris, Thomas Gregory

    We describe a low-cost (instrument cost) technique for joint distraction using 2 Kirschner wires and a toothed lamina spreader in lieu of a Hintermann distractor. The described technique allows for temporary intra-articular distraction and visualization and preservation of the articular surface with extra-articular instrumentation. The technique can also allow for closed reduction and percutaneous treatment in cases of soft tissue compromise. Additionally, the technique uses common orthopedic surgical instruments, leading to a minimal learning curve for novice surgeons. We have found this distraction technique to be most effective for intra-articular preparation of hindfoot and midfoot arthrodeses and for navicular fracture reduction. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  11. Strengthening of defected beam–column joints using CFRP

    Directory of Open Access Journals (Sweden)

    Mohamed H. Mahmoud

    2014-01-01

    Full Text Available This paper presents an experimental study for the structural performance of reinforced concrete (RC exterior beam–column joints rehabilitated using carbon-fiber-reinforced polymer (CFRP. The present experimental program consists of testing 10 half-scale specimens divided into three groups covering three possible defects in addition to an adequately detailed control specimen. The considered defects include the absence of the transverse reinforcement within the joint core, insufficient bond length for the beam main reinforcement and inadequate spliced implanted column on the joint. Three different strengthening schemes were used to rehabilitate the defected beam–column joints including externally bonded CFRP strips and sheets in addition to near surface mounted (NSM CFRP strips. The failure criteria including ultimate capacity, mode of failure, initial stiffness, ductility and the developed ultimate strain in the reinforcing steel and CFRP were considered and compared for each group for the control and the CFRP-strengthened specimens. The test results showed that the proposed CFRP strengthening configurations represented the best choice for strengthening the first two defects from the viewpoint of the studied failure criteria. On the other hand, the results of the third group showed that strengthening the joint using NSM strip technique enabled the specimen to outperform the structural performance of the control specimen while strengthening the joints using externally bonded CFRP strips and sheets failed to restore the strengthened joints capacity.

  12. Strengthening of defected beam-column joints using CFRP.

    Science.gov (United States)

    Mahmoud, Mohamed H; Afefy, Hamdy M; Kassem, Nesreen M; Fawzy, Tarek M

    2014-01-01

    This paper presents an experimental study for the structural performance of reinforced concrete (RC) exterior beam-column joints rehabilitated using carbon-fiber-reinforced polymer (CFRP). The present experimental program consists of testing 10 half-scale specimens divided into three groups covering three possible defects in addition to an adequately detailed control specimen. The considered defects include the absence of the transverse reinforcement within the joint core, insufficient bond length for the beam main reinforcement and inadequate spliced implanted column on the joint. Three different strengthening schemes were used to rehabilitate the defected beam-column joints including externally bonded CFRP strips and sheets in addition to near surface mounted (NSM) CFRP strips. The failure criteria including ultimate capacity, mode of failure, initial stiffness, ductility and the developed ultimate strain in the reinforcing steel and CFRP were considered and compared for each group for the control and the CFRP-strengthened specimens. The test results showed that the proposed CFRP strengthening configurations represented the best choice for strengthening the first two defects from the viewpoint of the studied failure criteria. On the other hand, the results of the third group showed that strengthening the joint using NSM strip technique enabled the specimen to outperform the structural performance of the control specimen while strengthening the joints using externally bonded CFRP strips and sheets failed to restore the strengthened joints capacity.

  13. Strengthened glass for high average power laser applications

    International Nuclear Information System (INIS)

    Cerqua, K.A.; Lindquist, A.; Jacobs, S.D.; Lambropoulos, J.

    1987-01-01

    Recent advancements in high repetition rate and high average power laser systems have put increasing demands on the development of improved solid state laser materials with high thermal loading capabilities. The authors have developed a process for strengthening a commercially available Nd doped phosphate glass utilizing an ion-exchange process. Results of thermal loading fracture tests on moderate size (160 x 15 x 8 mm) glass slabs have shown a 6-fold improvement in power loading capabilities for strengthened samples over unstrengthened slabs. Fractographic analysis of post-fracture samples has given insight into the mechanism of fracture in both unstrengthened and strengthened samples. Additional stress analysis calculations have supported these findings. In addition to processing the glass' surface during strengthening in a manner which preserves its post-treatment optical quality, the authors have developed an in-house optical fabrication technique utilizing acid polishing to minimize subsurface damage in samples prior to exchange treatment. Finally, extension of the strengthening process to alternate geometries of laser glass has produced encouraging results, which may expand the potential or strengthened glass in laser systems, making it an exciting prospect for many applications

  14. Microstructure and mechanical properties of ZrO{sub 2} particle dispersion strengthened 16MnV steel

    Energy Technology Data Exchange (ETDEWEB)

    Wang, B.A. [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Wang, N. [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); CNOOC Research Institute of Oil and Petrochemicals (CRI), Beijing 100000 (China); Yang, Y.J.; Zhong, H. [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Ma, M.Z., E-mail: mz550509@ysu.edu.cn [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Zhang, X.Y.; Liu, R.P. [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China)

    2017-04-24

    The dispersion strengthened 16MnV steels with 0.5 wt% and 1.2 wt% ZrO{sub 2} particles were prepared using medium frequency induction melting furnace. The ZrO{sub 2} particles mixed with iron powder were added into the 16MnV steel through cored-wire injection process. Optical metallographic microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM) were used to observe and analyze the microstructure, fracture morphology, dislocation configuration and strengthening mechanism of ZrO{sub 2} particle dispersion strengthened 16MnV steel under as-cast, normalizing and quenching states. Results showed that the strength of 16MnV steel under various states increased significantly after the addition of dispersed ZrO{sub 2} particles. Analysis indicates that the dislocation cell formed by high density dislocation around ZrO{sub 2} particles and attractive interaction between those particles are the main strengthening mechanism of dispersion strengthened 16MnV steel. The tensile test results showed that remarkable strengthening effect of ZrO{sub 2} particle on 16MnV steel has been observed. As the addition of 1.2 wt% ZrO{sub 2}, the improvement of strength in ZrO{sub 2}/16MnV is approximately 37.69% for as-casting, 24.2% after normalization and 29.96% after quenching, respectively. The normalized ZrO{sub 2}/16MnV with 1.2 wt% ZrO{sub 2} has the highest strength of 1453 MPa.

  15. Evaluating the performance of skewed prestressed concrete bridge after strengthening

    Science.gov (United States)

    Naser, Ali Fadhil; Zonglin, Wang

    2013-06-01

    The objectives of this paper are to explain the application of repairing and strengthening methods on the damaged members of the bridge structure, to analyze the static and dynamic structural response under static and dynamic loads after strengthening, and to evaluate the structural performance after application of strengthening method. The repairing and strengthening methods which are used in this study include treatment of the cracks, thickening the web of box girder along the bridge length and adding internal pre-stressing tendons in the thickening web, and construct reinforced concrete cross beams (diaphragms) between two box girders. The results of theoretical analysis of static and dynamic structural responses after strengthening show that the tensile stresses are decreased and become less than the allowable limit values in the codes. The values of vertical deflection are decreased after strengthening. The values of natural frequencies after strengthening are increased, indicating that the strengthening method is effective to reduce the vibration of the bridge structure. Therefore, the strengthening methods are effective to improve the bearing capacity and elastic working state of the bridge structure and to increase the service life of the bridge structure.

  16. Requirement of cAMP signaling for Schwann cell differentiation restricts the onset of myelination.

    Directory of Open Access Journals (Sweden)

    Ketty Bacallao

    Full Text Available Isolated Schwann cells (SCs respond to cAMP elevation by adopting a differentiated post-mitotic state that exhibits high levels of Krox-20, a transcriptional enhancer of myelination, and mature SC markers such as the myelin lipid galactocerebroside (O1. To address how cAMP controls myelination, we performed a series of cell culture experiments which compared the differentiating responses of isolated and axon-related SCs to cAMP analogs and ascorbate, a known inducer of axon ensheathment, basal lamina formation and myelination. In axon-related SCs, cAMP induced the expression of Krox-20 and O1 without a concomitant increase in the expression of myelin basic protein (MBP and without promoting axon ensheathment, collagen synthesis or basal lamina assembly. When cAMP was provided together with ascorbate, a dramatic enhancement of MBP expression occurred, indicating that cAMP primes SCs to form myelin only under conditions supportive of basal lamina formation. Experiments using a combination of cell permeable cAMP analogs and type-selective adenylyl cyclase (AC agonists and antagonists revealed that selective transmembrane AC (tmAC activation with forskolin was not sufficient for full SC differentiation and that the attainment of an O1 positive state also relied on the activity of the soluble AC (sAC, a bicarbonate sensor that is insensitive to forskolin and GPCR activation. Pharmacological and immunological evidence indicated that SCs expressed sAC and that sAC activity was required for morphological differentiation and the expression of myelin markers such as O1 and protein zero. To conclude, our data indicates that cAMP did not directly drive myelination but rather the transition into an O1 positive state, which is perhaps the most critical cAMP-dependent rate limiting step for the onset of myelination. The temporally restricted role of cAMP in inducing differentiation independently of basal lamina formation provides a clear example of the

  17. Pernicious anaemia and mucosal endocrine cell proliferation of the non-antral stomach.

    OpenAIRE

    Rode, J; Dhillon, A P; Papadaki, L; Stockbrügger, R; Thompson, R J; Moss, E; Cotton, P B

    1986-01-01

    There is a recognised association between pernicious anaemia and the development of gastric carcinoma, endocrine cell hyperplasia, and carcinoid tumour. Multiple endoscopic biopsies from the body mucosa of seven patients with pernicious anaemia showed small intestinal metaplasia with varying degrees of inflammation, fibrosis, and expansion of the lamina propria. Using conventional silver and lead stains, endocrine cells were inconspicuous. Staining for the general neural and neuroendocrine ma...

  18. Ultrastructure of interstitial cells of Cajal in myenteric plexus of human colon

    DEFF Research Database (Denmark)

    Rumessen, Jüri Johs.; Vanderwinden, Jean-Marie; Rasmussen, Helle

    2009-01-01

    and had myoid features such as scattered caveolae, prominent intermediate filaments, and cytoplasmic dense bodies. We found characteristic dense membrane-associated bands with a patchy basal lamina, invaginating cellular protrusions (peg and socket junctions) between ICC and between ICC and muscle cells......, and close contacts (socket...

  19. Timber Elements: Traditional and Modern Strengthening Techniques

    Directory of Open Access Journals (Sweden)

    Raluca Hohan

    2010-01-01

    Full Text Available The main idea of this paper is to analyse the means for the rehabilitation of our cultural heritage timber structures. Several methods together with their application techniques are described, and also, the reasons for what these strengthening operations become imminent at a point. First of all, the necessity of the timber structural elements strengthening is explained through a short presentation of the factors which are degrading the material. Then, certain precautions and strengthening procedures are presented, all involving the usage of traditional materials like wood, metal, or concrete, and of modern materials like fiber reinforced polymeric composite.

  20. The basis for the strengthening of safeguards

    International Nuclear Information System (INIS)

    Goldschmidt, P.

    1999-01-01

    For the past 30 years, the International Atomic Energy Agency's safeguards system has contributed to the international non-proliferation regime, by providing, inter alia, assurances regarding the peaceful uses of declared nuclear material. However, the discovery of a clandestine nuclear weapons programme in Iraq in 1991 drew world-wide attention to the need to strengthen the system to address the absence of undeclared nuclear material and activities. Efforts to strengthen the IAEA's safeguards system began in 1991 and culminated in 1997 when the IAEA's Board of Governors approved a Model Protocol Additional to IAEA Safeguards Agreements which greatly expands the legal basis and scope of IAEA safeguards. Within this strengthened system it is expected that the IAEA be able to provide assurance not only of the absence of diversion of declared nuclear material but also on the absence of undeclared nuclear material and activities. This is to be done within a safeguards system that uses an optimal combination of all safeguards measures available, thereby achieving maximum effectiveness and efficiency within the available resources. This paper will summarize the evolution of the safeguards system, describe strengthened safeguards, report on the status of implementing the strengthening measures, and outline plans for integrating all available safeguards measures. (author)

  1. Strengthening quitter self-identity: An experimental study.

    Science.gov (United States)

    Meijer, Eline; Gebhardt, Winifred A; van Laar, Colette; van den Putte, Bas; Evers, Andrea W M

    2018-06-10

    Smoking-related self-identity processes are important for smoking cessation. We examined whether quitter self-identity (i.e. identification with quitting smoking) could be strengthened through a writing exercise, and whether expected social support for quitting, manipulated through vignettes, could facilitate identification with quitting. Participants (N = 339 daily smokers) were randomly assigned to a 2 (identity: strengthened quitter self-identity vs. control) × 3 (social support: present vs. absent vs. neutral control) between-participants design. The main outcome was post-test quitter self-identity. Post-test quitter self-identity was not strengthened successfully. Only a small and marginally significant intervention effect was found on quitter self-identity, which did not generalise to positively influence quit-intention or behaviour. The social support manipulation did not facilitate quitter self-identity. Secondary content analyses showed that quitter self-identity was strengthened among participants who linked quitting smoking to their lifestyle, wanted to become quitters for health reasons, and whose reasons for becoming quitters included approach of positive aspects of quitting, but not among participants who linked quitter self-identity to their self-perceptions. Results provide insight into the content of smokers' self-conceptualizations as quitters. Writing exercises should be improved and tested to eventually successfully strengthen quitter identities.

  2. Photosynthesis-related characteristics of the midrib and the interveinal lamina in leaves of the C3-CAM intermediate plant Mesembryanthemum crystallinum.

    Science.gov (United States)

    Kuźniak, Elżbieta; Kornas, Andrzej; Kaźmierczak, Andrzej; Rozpądek, Piotr; Nosek, Michał; Kocurek, Maciej; Zellnig, Günther; Müller, Maria; Miszalski, Zbigniew

    2016-06-01

    Leaf veins are usually encircled by specialized bundle sheath cells. In C4 plants, they play an important role in CO2 assimilation, and the photosynthetic activity is compartmentalized between the mesophyll and the bundle sheath. In C3 and CAM (Crassulacean acid metabolism) plants, the photosynthetic activity is generally attributed to the leaf mesophyll cells, and the vascular parenchymal cells are rarely considered for their role in photosynthesis. Recent studies demonstrate that enzymes required for C4 photosynthesis are also active in the veins of C3 plants, and their vascular system contains photosynthetically competent parenchyma cells. However, our understanding of photosynthesis in veins of C3 and CAM plants still remains insufficient. Here spatial analysis of photosynthesis-related properties were applied to the midrib and the interveinal lamina cells in leaves of Mesembryanthemum crystallinum, a C3-CAM intermediate plant. The midrib anatomy as well as chloroplast structure and chlorophyll fluorescence, diurnal gas exchange profiles, the immunoblot patterns of PEPC (phosphoenolpyruvate carboxylase) and RubisCO (ribulose-1,5-bisphosphate carboxylase/oxygenase), H2O2 localization and antioxidant enzyme activities were compared in the midrib and in the interveinal mesophyll cells in leaves of C3 and CAM plants. Leaf midribs were structurally competent to perform photosynthesis in C3 and CAM plants. The midrib chloroplasts resembled those in the bundle sheath cells of C4 plants and were characterized by limited photosynthetic activity. The metabolic roles of midrib chloroplasts differ in C3 and CAM plants. It is suggested that in leaves of C3 plants the midrib chloroplasts could be involved in the supply of CO2 for carboxylation, and in CAM plants they could provide malate to different metabolic processes and mediate H2O2 signalling. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For

  3. Persistent changes in circulating and intestinal γδ T cell subsets, invariant natural killer T cells and mucosal-associated invariant T cells in children and adults with coeliac disease.

    Science.gov (United States)

    Dunne, Margaret R; Elliott, Louise; Hussey, Seamus; Mahmud, Nasir; Kelly, Jacinta; Doherty, Derek G; Feighery, Conleth F

    2013-01-01

    Coeliac disease is a chronic small intestinal immune-mediated enteropathy precipitated by exposure to dietary gluten in genetically predisposed individuals. The only current therapy is a lifelong gluten free diet. While much work has focused on the gliadin-specific adaptive immune response in coeliac disease, little is understood about the involvement of the innate immune system. Here we used multi-colour flow cytometry to determine the number and frequency of γδ T cells (Vδ1, Vδ2 and Vδ3 subsets), natural killer cells, CD56(+) T cells, invariant NKT cells, and mucosal associated invariant T cells, in blood and duodenum from adults and children with coeliac disease and healthy matched controls. All circulating innate lymphocyte populations were significantly decreased in adult, but not paediatric coeliac donors, when compared with healthy controls. Within the normal small intestine, we noted that Vδ3 cells were the most abundant γδ T cell type in the adult epithelium and lamina propria, and in the paediatric lamina propria. In contrast, patients with coeliac disease showed skewing toward a predominant Vδ1 profile, observed for both adult and paediatric coeliac disease cohorts, particularly within the gut epithelium. This was concurrent with decreases in all other gut lymphocyte subsets, suggesting a specific involvement of Vδ1 cells in coeliac disease pathogenesis. Further analysis showed that γδ T cells isolated from the coeliac gut display an activated, effector memory phenotype, and retain the ability to rapidly respond to in vitro stimulation. A profound loss of CD56 expression in all lymphocyte populations was noted in the coeliac gut. These findings demonstrate a sustained aberrant innate lymphocyte profile in coeliac disease patients of all ages, persisting even after elimination of gluten from the diet. This may lead to impaired immunity, and could potentially account for the increased incidence of autoimmune co-morbidity.

  4. Persistent changes in circulating and intestinal γδ T cell subsets, invariant natural killer T cells and mucosal-associated invariant T cells in children and adults with coeliac disease.

    Directory of Open Access Journals (Sweden)

    Margaret R Dunne

    Full Text Available Coeliac disease is a chronic small intestinal immune-mediated enteropathy precipitated by exposure to dietary gluten in genetically predisposed individuals. The only current therapy is a lifelong gluten free diet. While much work has focused on the gliadin-specific adaptive immune response in coeliac disease, little is understood about the involvement of the innate immune system. Here we used multi-colour flow cytometry to determine the number and frequency of γδ T cells (Vδ1, Vδ2 and Vδ3 subsets, natural killer cells, CD56(+ T cells, invariant NKT cells, and mucosal associated invariant T cells, in blood and duodenum from adults and children with coeliac disease and healthy matched controls. All circulating innate lymphocyte populations were significantly decreased in adult, but not paediatric coeliac donors, when compared with healthy controls. Within the normal small intestine, we noted that Vδ3 cells were the most abundant γδ T cell type in the adult epithelium and lamina propria, and in the paediatric lamina propria. In contrast, patients with coeliac disease showed skewing toward a predominant Vδ1 profile, observed for both adult and paediatric coeliac disease cohorts, particularly within the gut epithelium. This was concurrent with decreases in all other gut lymphocyte subsets, suggesting a specific involvement of Vδ1 cells in coeliac disease pathogenesis. Further analysis showed that γδ T cells isolated from the coeliac gut display an activated, effector memory phenotype, and retain the ability to rapidly respond to in vitro stimulation. A profound loss of CD56 expression in all lymphocyte populations was noted in the coeliac gut. These findings demonstrate a sustained aberrant innate lymphocyte profile in coeliac disease patients of all ages, persisting even after elimination of gluten from the diet. This may lead to impaired immunity, and could potentially account for the increased incidence of autoimmune co-morbidity.

  5. Cable strengthened arches

    NARCIS (Netherlands)

    Kamerling, M.W.

    2013-01-01

    The structural efficiency of arches, subjected to several variable loads, can be increased by strengthening these arches with cables. For these structures it can be necessary, especially in case the permanent load is small, to post-tension the cables to avoid any compression acting on the cables. A

  6. Modeling of crack propagation in strengthened concrete disks

    DEFF Research Database (Denmark)

    Hansen, Christian Skodborg; Stang, Henrik

    2013-01-01

    Crack propagation in strengthened concrete disks is a problem that has not yet been addressed properly. To investigate it, a cracked half-infinite disk of concrete is strengthened with a linear elastic material bonded to the surface, and analyzed using two different finite element modeling...... instead of 3D calculations to predict the response of a structure and that it opens up for simpler evaluation of strengthened concrete structures using the finite element method....

  7. Changes in the interstitial cells of Cajal and neuronal nitric oxide synthase positive neuronal cells with aging in the esophagus of F344 rats.

    Science.gov (United States)

    Kim, Hee Jin; Kim, Nayoung; Kim, Yong Sung; Nam, Ryoung Hee; Lee, Sun Min; Park, Ji Hyun; Choi, Daeun; Hwang, Young-Jae; Lee, Jongchan; Lee, Hye Seung; Kim, Min-Seob; Lee, Moon Young; Lee, Dong Ho

    2017-01-01

    The aging-associated cellular and molecular changes in esophagus have not been established, yet. Thus we evaluated histological structure, interstitial cells of Cajal (ICCs), neuronal nitric oxide synthase (nNOS)-positive cells, and contractility in the esophagus of Fischer 344 rat at different ages (6-, 31-, 74-weeks, and 2-years). The lamina propria thickness and endomysial area were calculated. The immunoreactivity of c-Kit, nNOS and protein gene product (PGP) 9.5 was counted after immunohistochemistry. Expression of c-Kit, stem cell factor (SCF), nNOS and PGP 9.5 mRNA was measured by real-time PCR, and expression of c-Kit and nNOS protein was detected by Western blot. Isovolumetric contractile force measurement and electrical field stimulation (EFS) were conducted. The lamina propria thickness increased (6 week vs 2 year, P = 0.005) and the endomysial area of longitudinal muscle decreased with aging (6 week vs 2 year, Pcells and c-Kit-immunoreactive areas declined with aging (6 week vs 2 year; Paging (6 week vs 2 year; P = 0.006, P = 0.001 and P = 0.006, respectively), while the change of PGP 9.5 mRNA expression was not significant. Western blot showed the significant decreases of nNOS and c-Kit protein expression with aging (6 week vs 2 year; P = 0.008 and P = 0.012, respectively). The EFS-induced esophageal contractions significantly decreased in 2-yr-old rat compared with 6-wk-old rats, however, L-NG-Nitroarginine methylester did not significantly increase the spontaneous and EFS-induced contractions in the 6-wk- and 2-yr-old rat esophagus. In conclusion, an increase of lamina propria thickness, a decrease of endomysial area, c-Kit, SCF and NOS expression with preserved total enteric neurons, and contractility in aged rat esophagus may explain the aging-associated esophageal dysmotility.

  8. Cell-cell junctions: a target of acoustic overstimulation in the sensory epithelium of the cochlea

    Directory of Open Access Journals (Sweden)

    Zheng Guiliang

    2012-06-01

    Full Text Available Abstract Background Exposure to intense noise causes the excessive movement of the organ of Corti, stretching the organ and compromising sensory cell functions. We recently revealed changes in the transcriptional expression of multiple adhesion-related genes during the acute phases of cochlear damage, suggesting that the disruption of cell-cell junctions is an early event in the process of cochlear pathogenesis. However, the functional state of cell junctions in the sensory epithelium is not clear. Here, we employed graded dextran-FITC, a macromolecule tracer that is impermeable to the organ of Corti under physiological conditions, to evaluate the barrier function of cell junctions in normal and noise-traumatized cochlear sensory epithelia. Results Exposure to an impulse noise of 155 dB (peak sound pressure level caused a site-specific disruption in the intercellular junctions within the sensory epithelium of the chinchilla cochlea. The most vulnerable sites were the junctions among the Hensen cells and between the Hensen and Deiters cells within the outer zone of the sensory epithelium. The junction clefts that formed in the reticular lamina were permeable to 40 and 500 but not 2,000 kDa dextran-FITC macromolecules. Moreover, this study showed that the interruption of junction integrity occurred in the reticular lamina and also in the basilar membrane, a site that had been considered to be resistant to acoustic injury. Finally, our study revealed a general spatial correlation between the site of sensory cell damage and the site of junction disruption. However, the two events lacked a strict one-to-one correlation, suggesting that the disruption of cell-cell junctions is a contributing, but not the sole, factor for initiating acute sensory cell death. Conclusions Impulse noise causes the functional disruption of intercellular junctions in the sensory epithelium of the chinchilla cochlea. This disruption occurs at an early phase of cochlear

  9. Desempenho animal em pasto de aveia e azevém com distintas biomassas de lâminas foliares Animal performance in oat and Italian ryegrass pastures under leaf lamina biomass levels

    Directory of Open Access Journals (Sweden)

    Duilio Guerra Bandinelli

    2005-12-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito de biomassas de lâminas foliares no desempenho animal. Utilizou-se mistura de aveia (Avena strigosa Schreb e azevém (Lolium multiflorum Lam., para determinar quantidades adequadas de sua biomassa no manejo da pastagem. Foram realizados dois experimentos, na estação fria de 2002 e 2003. Na avaliação de 2002, os valores de biomassa de lâminas foliares foram de 360 kg ha-1 (baixa e 630 kg ha-1 (alta. Em 2003, foram obtidas biomassas de 352, 422 e 507 kg ha-1, classificadas como baixa, média e alta, respectivamente. O método de pastejo foi contínuo, com taxa de lotação variada; os animais utilizados foram terneiros da raça Charolês e cruzados com Nelore, com idade inicial de nove meses. As variáveis de produção animal avaliadas, nos dois anos, foram: ganho médio diário, carga animal e ganho de peso vivo por área. As distintas biomassas de lâminas foliares mantidas não são fatores limitantes ao desempenho animal.The objective of this work was to evaluate the effect of different leaf lamina biomass over animal performance. A mixture of oat (Avena strigosa Schreb and Italian ryegrass (Lolium multiflorum Lam. was used to determine adequate levels of leaf lamina biomass for pasture management. Two trials were made, in 2002 and 2003 cool seasons. In 2002 evaluation, leaf lamina biomass values were of 360 kg ha-1 (low and 630 kg ha-1 (high. In 2003, values obtained for leaf lamina biomasses were of 352, 422 and 507 kg ha-1, being classified as low, medium and high, respectively. Grazing method was continuous, with variable stocking rate; testing animals were calves of Charolais breed and its crosses with Nelore breed, with initial age of nine months. Evaluated variables in animal production, in both years, were: average daily gain, stocking rate and live weight gain per area. Leaf lamina biomasses evaluated are not limiting factors to animal performance.

  10. Ion exchange for glass strengthening

    International Nuclear Information System (INIS)

    Gy, Rene

    2008-01-01

    This paper presents a short overview of silicate glass strengthening by exchange of alkali ions in a molten salt, below the glass transition temperature (chemical tempering). The physics of alkali inter-diffusion is briefly explained and the main parameters of the process, which control the glass reinforcement, are reviewed. Methods for characterizing the obtained residual stress state and the strengthening are described, along with the simplified modelling of the stress build-up. The fragmentation of chemically tempered glass is discussed. The concept of engineered stress profile glass is presented, and finally, the effect of glass and salt compositions is overviewed

  11. Isolation, Culture, Functional Assays, and Immunofluorescence of Myofiber-Associated Satellite Cells.

    Science.gov (United States)

    Vogler, Thomas O; Gadek, Katherine E; Cadwallader, Adam B; Elston, Tiffany L; Olwin, Bradley B

    2016-01-01

    Adult skeletal muscle stem cells, termed satellite cells, regenerate and repair the functional contractile cells in adult skeletal muscle called myofibers. Satellite cells reside in a niche between the basal lamina and sarcolemma of myofibers. Isolating single myofibers and their associated satellite cells provides a culture system that partially mimics the in vivo environment. We describe methods for isolating and culturing intact individual myofibers and their associated satellite cells from the mouse extensor digitorum longus muscle. Following dissection and isolation of individual myofibers we provide protocols for myofiber transplantation, satellite cell transfection, immune detection of satellite cell antigens, and assays to examine satellite cell self-renewal and proliferation.

  12. Sulfide silver architectonics of rat, cat, and guinea pig spinal cord. A light microscopic study with Timm's method for demonstration of heavy metals

    DEFF Research Database (Denmark)

    Schroder, H D

    1977-01-01

    The distribution of heavy metals in the spinal cord of the cat, rat, and guinea pig has been studied histochemically with Timm's sulfide silver method. There was considerable variation in the degree of staining of the neuropil. The dorsal horn showed a laminar staining pattern corresponding...... to the cytoarchitectonic lamination. Lamina I in the cat and guinea pig was light. Lamina II in all three species was heavily stained. In the rat and guinea pig it could be subdivided in a ventral and a dorsal layer, and moreover in the rat a darkly staining borderzone abutting on lamina III was present. Lamina III......, characterized by heterogeneous staining, also appeared dark, although less obvious in the guinea pig. In the ventral horn the coarser stained particles in lamina IX contrasted with the surrounding lamina. Cell staining varied between different cell groups, and within single cell populations. In the cat thoracic...

  13. Microstructure characterization and strengthening mechanisms of oxide dispersion strengthened (ODS) Fe-9%Cr and Fe-14%Cr extruded bars

    Science.gov (United States)

    Chauhan, A.; Bergner, F.; Etienne, A.; Aktaa, J.; de Carlan, Y.; Heintze, C.; Litvinov, D.; Hernandez-Mayoral, M.; Oñorbe, E.; Radiguet, B.; Ulbricht, A.

    2017-11-01

    The collaborative study is focused on the relationship between microstructure and yield stress for an ODS Fe-9%Cr-based transformable alloy and an ODS Fe-14%Cr-based ferritic alloy. The contributions to the total room temperature yield stress arising from various strengthening mechanisms are addressed on the basis of a comprehensive description of the microstructures uncovered by means of transmission electron microscopy (TEM), electron backscatter diffraction (EBSD), small-angle neutron scattering (SANS) and atom probe tomography (APT). While these methods provide a high degree of complementarity, a reasonable agreement was found in cases of overlap of information. The derived set of microstructure parameters along with reported strengthening equations was used to calculate the room temperature yield stress. The estimates were critically compared with the measured yield stress for an extended set of alloys including data reported for Fe-Cr model alloys and steels thus covering one order of magnitude or more in grain size, dislocation density, particle density and yield stress. The comparison shows that particle strengthening, dislocation forest strengthening, and Hall-Petch strengthening are the major contributions and that a mixed superposition rule reproduces the measured yield stress within experimental scatter for the whole extended set of alloys. The wide variation of microstructures additionally underpins the conclusions and goes beyond previous work, in which one or few ODS steels and narrow microstructure variations were typically covered.

  14. NaCl and osmolarity produce different responses in organum vasculosum of the lamina terminalis neurons, sympathetic nerve activity and blood pressure.

    Science.gov (United States)

    Kinsman, Brian J; Browning, Kirsteen N; Stocker, Sean D

    2017-09-15

    Changes in extracellular osmolarity stimulate thirst and vasopressin secretion through a central osmoreceptor; however, central infusion of hypertonic NaCl produces a greater sympathoexcitatory and pressor response than infusion of hypertonic mannitol/sorbitol. Neurons in the organum vasculosum of the lamina terminalis (OVLT) sense changes in extracellular osmolarity and NaCl. In this study, we discovered that intracerebroventricular infusion or local OVLT injection of hypertonic NaCl increases lumbar sympathetic nerve activity, adrenal sympathetic nerve activity and arterial blood pressure whereas equi-osmotic mannitol/sorbitol did not alter any variable. In vitro whole-cell recordings demonstrate the majority of OVLT neurons are responsive to hypertonic NaCl or mannitol. However, hypertonic NaCl stimulates a greater increase in discharge frequency than equi-osmotic mannitol. Intracarotid or intracerebroventricular infusion of hypertonic NaCl evokes a greater increase in OVLT neuronal discharge frequency than equi-osmotic sorbitol. Collectively, these novel data suggest that subsets of OVLT neurons respond differently to hypertonic NaCl versus osmolarity and subsequently regulate body fluid homeostasis. These responses probably reflect distinct cellular mechanisms underlying NaCl- versus osmo-sensing. Systemic or central infusion of hypertonic NaCl and other osmolytes readily stimulate thirst and vasopressin secretion. In contrast, central infusion of hypertonic NaCl produces a greater increase in arterial blood pressure (ABP) than equi-osmotic mannitol/sorbitol. Although these responses depend on neurons in the organum vasculosum of the lamina terminalis (OVLT), these observations suggest OVLT neurons may sense or respond differently to hypertonic NaCl versus osmolarity. The purpose of this study was to test this hypothesis in Sprague-Dawley rats. First, intracerebroventricular (icv) infusion (5 μl/10 min) of 1.0 m NaCl produced a significantly greater

  15. Optimal cost for strengthening or destroying a given network

    Science.gov (United States)

    Patron, Amikam; Cohen, Reuven; Li, Daqing; Havlin, Shlomo

    2017-05-01

    Strengthening or destroying a network is a very important issue in designing resilient networks or in planning attacks against networks, including planning strategies to immunize a network against diseases, viruses, etc. Here we develop a method for strengthening or destroying a random network with a minimum cost. We assume a correlation between the cost required to strengthen or destroy a node and the degree of the node. Accordingly, we define a cost function c (k ) , which is the cost of strengthening or destroying a node with degree k . Using the degrees k in a network and the cost function c (k ) , we develop a method for defining a list of priorities of degrees and for choosing the right group of degrees to be strengthened or destroyed that minimizes the total price of strengthening or destroying the entire network. We find that the list of priorities of degrees is universal and independent of the network's degree distribution, for all kinds of random networks. The list of priorities is the same for both strengthening a network and for destroying a network with minimum cost. However, in spite of this similarity, there is a difference between their pc, the critical fraction of nodes that has to be functional to guarantee the existence of a giant component in the network.

  16. Potential of a polygonal prism and lamina; Takakuchu men no potential

    Energy Technology Data Exchange (ETDEWEB)

    Koyama, S

    1996-05-01

    With the use of rectangular coordinates O-XYZ, the potential of a calculation point P is expressed in the form of a triple repeated integral of a density {sigma} at point Q in the mass. The potential at the density {sigma} assumed to be 1 is named the potential of a polygonal prism. Further, a double repeated integral with an integral concerning Z removed from the triple integral is named the potential of polygonal lamina. This potential can be expressed in a quadratic form (linear form) with 2nd order partial derivative (1st order partial derivative) as a coefficient. On the contrary, in order to extract the 1st/2nd order partial derivatives from this potential by partial differential, it requires partial differentiation with these partial derivatives considered to be a constant. The reason that they can be realized is attributable to the zero result of the linear form which has as the coefficient a 3rd order partial derivative concerning the variable of integration in a primitive function. If this relation is used, the integral calculation and description may be simplified. An explanation was given with examples enumerated so that these conditions might be understood.

  17. Strengthening Mechanisms in Microtruss Metals

    Science.gov (United States)

    Ng, Evelyn K.

    Microtrusses are hybrid materials composed of a three-dimensional array of struts capable of efficiently transmitting an externally applied load. The strut connectivity of microtrusses enables them to behave in a stretch-dominated fashion, allowing higher specific strength and stiffness values to be reached than conventional metal foams. While much attention has been given to the optimization of microtruss architectures, little attention has been given to the strengthening mechanisms inside the materials that make up this architecture. This thesis examines strengthening mechanisms in aluminum alloy and copper alloy microtruss systems with and without a reinforcing structural coating. C11000 microtrusses were stretch-bend fabricated for the first time; varying internal truss angles were selected in order to study the accumulating effects of plastic deformation and it was found that the mechanical performance was significantly enhanced in the presence of work hardening with the peak strength increasing by a factor of three. The C11000 microtrusses could also be significantly reinforced with sleeves of electrodeposited nanocrystalline Ni-53wt%Fe. It was found that the strength increase from work hardening and electrodeposition were additive over the range of structures considered. The AA2024 system allowed the contribution of work hardening, precipitation hardening, and hard anodizing to be considered as interacting strengthening mechanisms. Because of the lower formability of AA2024 compared to C11000, several different perforation geometries in the starting sheet were considered in order to more effectively distribute the plastic strain during stretch-bend fabrication. A T8 condition was selected over a T6 condition because it was shown that the plastic deformation induced during the final step was sufficient to enhance precipitation kinetics allowing higher strengths to be reached, while at the same time eliminating one annealing treatment. When hard anodizing

  18. Comparison of 640-Slice Multidetector Computed Tomography Versus 32-Slice MDCT for Imaging of the Osteo-odonto-keratoprosthesis Lamina.

    Science.gov (United States)

    Norris, Joseph M; Kishikova, Lyudmila; Avadhanam, Venkata S; Koumellis, Panos; Francis, Ian S; Liu, Christopher S C

    2015-08-01

    To investigate the efficacy of 640-slice multidetector computed tomography (MDCT) for detecting osteo-odonto laminar resorption in the osteo-odonto-keratoprosthesis (OOKP) compared with the current standard 32-slice MDCT. Explanted OOKP laminae and bone-dentine fragments were scanned using 640-slice MDCT (Aquilion ONE; Toshiba) and 32-slice MDCT (LightSpeed Pro32; GE Healthcare). Pertinent comparisons including image quality, radiation dose, and scanning parameters were made. Benefits of 640-slice MDCT over 32-slice MDCT were shown. Key comparisons of 640-slice MDCT versus 32-slice MDCT included the following: percentage difference and correlation coefficient between radiological and anatomical measurements, 1.35% versus 3.67% and 0.9961 versus 0.9882, respectively; dose-length product, 63.50 versus 70.26; rotation time, 0.175 seconds versus 1.000 seconds; and detector coverage width, 16 cm versus 2 cm. Resorption of the osteo-odonto lamina after OOKP surgery can result in potentially sight-threatening complications, hence it warrants regular monitoring and timely intervention. MDCT remains the gold standard for radiological assessment of laminar resorption, which facilitates detection of subtle laminar changes earlier than the onset of clinical signs, thus indicating when preemptive measures can be taken. The 640-slice MDCT exhibits several advantages over traditional 32-slice MDCT. However, such benefits may not offset cost implications, except in rare cases, such as in young patients who might undergo years of radiation exposure.

  19. Writing Strengthens Orthography and Alphabetic-Coding Strengthens Phonology in Learning to Read Chinese

    NARCIS (Netherlands)

    Guan, C.Q.; Liu, Y.; Chan, D.H.L.; Ye, F.F.; Perfetti, C.A.

    2011-01-01

    Learning to write words may strengthen orthographic representations and thus support word-specific recognition processes. This hypothesis applies especially to Chinese because its writing system encourages character-specific recognition that depends on accurate representation of orthographic form.

  20. STRENGTHENING OF A REINFORCED CONCRETE BRIDGE WITH PRESTRESSED STEEL WIRE ROPES

    Directory of Open Access Journals (Sweden)

    Kexin Zhang

    2017-10-01

    Full Text Available This paper describes prestressed steel wire ropes as a way to strengthen a 20-year-old RC T-beam bridge. High strength, low relaxation steel wire ropes with minor radius, high tensile strain and good corrosion resistance were used in this reinforcement. The construction process for strengthening with prestressed steel wire ropes—including wire rope measuring, extruding anchor heads making, anchorage installing, tensioning steel wire ropes and pouring mortar was described. Ultimate bearing capacity of the bridge after strengthening was discussed based on the concrete structure theory. The flexural strength of RC T-beam bridges strengthened with prestressed steel wire ropes was governed by the failure of concrete crushing. To investigate effectiveness of the strengthening method, fielding-load tests were carried out before and after strengthening. The results of concrete strain and deflection show that the flexural strength and stiffness of the strengthened beam are improved. The crack width measurement also indicates that this technique could increase the durability of the bridge. Thus, this strengthened way with prestressed steel wire rope is feasible and effective.

  1. Stromatolite laminae (Lagoa Vermelha, Brasil) as archives for reservoir age changes

    Science.gov (United States)

    Bruggmann, Sylvie; Vasconcelos, Crisogono; Hajdas, Irka

    2016-04-01

    As laminated biogenic or abiogenic sedimentary structures [1], stromatolites record environmental changes along growth profiles, revealing possible changes in reservoir ages due to input of older carbon. A modern stromatolite sample was collected in Lagoa Vermelha (100 km east of Rio de Janeiro, Brasil) an area known for upwelling of South Atlantic Central Water (SACW). 34 samples from a transect cutting the lamination were collected with a hand-driller for standard geochemistry and 14C AMS analyses. Shells collected in 2015 were analysed for estimation of the present-day reservoir age. 14C ages of laminae and the reservoir age were used to apply the age-depth model to the stromatolite transect with the OxCal depositional model (Marine13 calibration curve; [2]). Small-scale changes in the composition of laminae report environmental changes, e.g. upwelling. The well-laminated middle part (laminated boundstone; ca. 4cm) of the stromatolite transect was found to have grown in a short time period of less than 100 years (1163-1210 14C y BP), with four excursions towards older 14C ages (ca. 1200 14C y BP). To detect possible changes of marine 14C, calendar years assuming a stable modern reservoir age were used to simulate atmospheric 14C ages with the southern hemisphere IntCal13 atmospheric calibration curve [3]. The offset between the measured and simulated 14C ages indicates a variability of the reservoir age between -99 and 268 14C y with highest reservoir correction found for the layers with indication of environmental changes (e.g. upwelling). Thus, this simulation confirms the occurrence of older carbon and points out the sensitivity of stromatolites for changing reservoir ages. [1] M.A. Semikhatov, C.D. Gebelein, P. Cloud, S.M. Awramik, W.C. Benmore (1979). Stromatolite morphogenesis - progress and problems. Canadian Journal of Earth Sciences, 19:992-1015. [2] P.J. Reimer, E. Bard, A. Bayliss, J. W. Beck, P. G. Blackwell, C. Bronk Ramsey, C. E. Buck, H. Cheng, R

  2. Disruption of basal lamina components in neuromotor synapses of children with spastic quadriplegic cerebral palsy.

    Directory of Open Access Journals (Sweden)

    Karyn G Robinson

    Full Text Available Cerebral palsy (CP is a static encephalopathy occurring when a lesion to the developing brain results in disordered movement and posture. Patients present with sometimes overlapping spastic, athetoid/dyskinetic, and ataxic symptoms. Spastic CP, which is characterized by stiff muscles, weakness, and poor motor control, accounts for ∼80% of cases. The detailed mechanisms leading to disordered movement in spastic CP are not completely understood, but clinical experience and recent studies suggest involvement of peripheral motor synapses. For example, it is recognized that CP patients have altered sensitivities to drugs that target neuromuscular junctions (NMJs, and protein localization studies suggest that NMJ microanatomy is disrupted in CP. Since CP originates during maturation, we hypothesized that NMJ disruption in spastic CP is associated with retention of an immature neuromotor phenotype later in life. Scoliosis patients with spastic CP or idiopathic disease were enrolled in a prospective, partially-blinded study to evaluate NMJ organization and neuromotor maturation. The localization of synaptic acetylcholine esterase (AChE relative to postsynaptic acetylcholine receptor (AChR, synaptic laminin β2, and presynaptic vesicle protein 2 (SV2 appeared mismatched in the CP samples; whereas, no significant disruption was found between AChR and SV2. These data suggest that pre- and postsynaptic NMJ components in CP children were appropriately distributed even though AChE and laminin β2 within the synaptic basal lamina appeared disrupted. Follow up electron microscopy indicated that NMJs from CP patients appeared generally mature and similar to controls with some differences present, including deeper postsynaptic folds and reduced presynaptic mitochondria. Analysis of maturational markers, including myosin, syntrophin, myogenin, and AChR subunit expression, and telomere lengths, all indicated similar levels of motor maturation in the two groups

  3. Stratification in the lunar regolith - a preliminary view

    International Nuclear Information System (INIS)

    Duke, M.B.; Nagle, J.S.

    1975-01-01

    Although the knowledge of lunar regolith stratification is incomplete, several categories of thick and thin strata have been identified. Relatively thick units average 2 to 3 cm in thickness, and appear surficially to be massive. On more detailed examination, these units can be uniformly fine-grained, can show internal trends, or can show internal variations which apparently are random. Other thick units contain soil clasts apparently reworked from underlying units. Thin laminae average approximately 1 mm in thickness; lenticular distribution and composition of some thin laminae indicates they are fillets shed from adjacent rock fragments. Other dark, fine-grained, well-sorted thin laminae appear to be surficial zones, reworked by micrometeorites. Interpretations of stratigraphic succession can be strengthened by the occurrence of characteristic coarse rock fragments and the orientation of large spatter agglutinates, which are commonly found in their original depositional orientation. (Auth.)

  4. Condition assessment and strengthening of residential units

    Directory of Open Access Journals (Sweden)

    Tatheer Zahra

    2014-01-01

    Full Text Available About 40, ground plus one (G+1 residential units were designed using a hybrid structural framing system (RC frame and load bearing walls. A few months after the completion of the ground floor of the residential units, cracks appeared at several locations in the structure. Field and Laboratory testing was conducted to ascertain the in situ strength of concrete and steel reinforcement. The results of the experimental work were used in the analytical ETABS model for the structural stability calculations. The results indicated that residential units were marginally safe in the existing condition (completed ground floor, but the anticipated construction of the floor above the ground floor (G+1 could not be carried out as the strength of the structural system was inadequate. To increase the safety of existing ground floor and to provide the option of the construction of one floor above, rehabilitation and strengthening design was performed. The proposed strengthening design made use of welded wire fabric (WWF and carbon fibre reinforced polymer (CFRP laminates/sheets for the strengthening of walls, columns and slabs. The residential units will be strengthened in the near future.

  5. Self-flowing mortar for ferrocement in strengthening applications

    Directory of Open Access Journals (Sweden)

    Shamir Sakir

    2016-09-01

    Full Text Available Ferrocement technology is becoming more and more important nowadays for strengthening and retrofitting of concrete structures mainly due to its inherent strength properties. However, its labour intensive nature makes it undesirable for rapid strengthening works. In narrow spaces, strengthening with conventional ferrocement is very critical and also time consuming. Self-flowing mortar (SFM could be used with this technology to overcome these limitations. This article discusses the applicability of SFM in ferrocement technology. The aim of this study is to summarize available knowledge on SFM to make it feasible for optimization in different industrial applications.

  6. Effect of horizontal reinforcement in strengthening of masonry members

    International Nuclear Information System (INIS)

    Farooq, S.H.; Ilyas, M.; Ggaffar, A.

    2008-01-01

    An experimental research program was undertaken to ascertain the effectiveness of a new technique for strengthening masonry wall panels using steel strips on compressive and shear strength enhancement. The experimental work includes eight wall panels, four each for compressive and shear strength evaluation. This work was the phase I of extensive research project which include testing of strengthened masonry wall panels under monotonic load (Phase-I), static cyclic load (Phase-2) and dynamic load (Phase-3). The wall panels were strengthened with different steel strip arrangements, which consist of single/double face application of coarse and fine steel strip mesh with reduced spacing of horizontal strips. This paper investigates only the effectiveness of horizontal steel strips on strength enhancement. Four masonry wall panels are considered in two groups and in each group, one wall was retrofitted with coarse steel mesh on single face and on second wall fine steel mesh was applied on one side. Furthermore, test results of strengthened specimens are also compared with the un-strengthened specimen (REFE). The mechanisms by which load was carried were observed, varying from the initial, uncracked state, and the final, fully cracked state. The results demonstrate a quite significant increase in the compressive and shear capacity of strengthened panels as compared to REFE-panel. However, increase in the compressive strength of fine mesh above that of coarse mesh is negligible. The technique/approach is found quite viable for strengthening of masonry walls, for rehabilitation of old deteriorated buildings and unreinforced masonry structures in seismic zones. (author)

  7. Strengthening from Nb-rich clusters in a Nb-microalloyed steel

    International Nuclear Information System (INIS)

    Xie, Kelvin Y.; Zheng, Tianxiao; Cairney, Julie M.; Kaul, Harold; Williams, James G.; Barbaro, Frank J.; Killmore, Chris R.; Ringer, Simon P.

    2012-01-01

    We demonstrate that a Nb-microalloyed ultra-thin cast strip steel can be strengthened substantially without compromising ductility by performing a simple heat treatment at 700 °C for 4 min. The strengthening was attributed to a fine dispersion of Nb-rich solute atom clusters. These clusters had an average size of ∼60 atoms at peak hardness and resembled Guinier–Preston zones in Al–Cu alloys. The application of the Ashby–Orowan equation indicates that these clusters are potent strengthening agents when compared to conventional Nb(C,N) precipitation strengthening.

  8. Improving the engineering strength of heat strengthened glass

    NARCIS (Netherlands)

    Veer, F.A.; Rodichev, YM

    2016-01-01

    Although glass is increasingly used as a structural material, glass is not produced to strength standards, like steel and concrete. Of the three types of glass: annealed, heat strengthened and fully tempered, only heat strengthened glass has the properties to function as a safe structural material.

  9. New concept of critical infrastructure strengthening

    International Nuclear Information System (INIS)

    Gazizov, Talgat R.; Orlov, Pavel E.; Zabolotsky, Alexander M.; Kuksenko, Sergey P.

    2016-01-01

    Strengthening of critical infrastructure is considered. Modal reservation of electronics is proposed as a new concept of the strengthening. The concept combines a widely used cold backup and a recently proposed modal filtration. It makes electronics reliable as well as protected against electromagnetic interference, especially the ultra-wide band pulses. New printed circuit board structure is suggested for implementation of the proposed concept. Results of simulation in time and frequency domains are presented for the suggested structures. Considerable attenuation of dangerous excitations shows that the new concept and structure are promising.

  10. New concept of critical infrastructure strengthening

    Energy Technology Data Exchange (ETDEWEB)

    Gazizov, Talgat R.; Orlov, Pavel E.; Zabolotsky, Alexander M.; Kuksenko, Sergey P. [Tomsk State University of Control Systems and Radioelectronics, 634050, Lenin Ave., Tomsk (Russian Federation)

    2016-06-08

    Strengthening of critical infrastructure is considered. Modal reservation of electronics is proposed as a new concept of the strengthening. The concept combines a widely used cold backup and a recently proposed modal filtration. It makes electronics reliable as well as protected against electromagnetic interference, especially the ultra-wide band pulses. New printed circuit board structure is suggested for implementation of the proposed concept. Results of simulation in time and frequency domains are presented for the suggested structures. Considerable attenuation of dangerous excitations shows that the new concept and structure are promising.

  11. Strengthening Masonry Arches with Lime-Based Mortar Composite

    Directory of Open Access Journals (Sweden)

    Valerio Alecci

    2017-06-01

    Full Text Available In recent decades, many strengthening interventions on masonry elements were performed by using fiber reinforced polymers (FRPs. These advanced materials proved to be effective to increase the load-carrying capacity of masonry elements and to improve their structural behavior, avoiding the most critical failure modes. Despite the advantages of this technique compared to more traditional methods, FRP systems have disadvantages related to their low resistance to high temperatures, impossibility of application on wet surfaces, low permeability, and poor compatibility with masonry supports. Therefore, composite materials made of a fiber textile embedded in an inorganic matrix were recently proposed as alternatives to FRPs for strengthening historic masonry constructions. These composite materials are easier to install, have higher resistance to high temperatures, and permit higher vapor permeability than FRPs. The inorganic matrix is frequently a cement-based mortar, and the composite materials made of a fiber textile embedded in a cement-based mortar are usually identified as FRCM (fabric reinforced cementitious matrix composites. More recently, the use of natural lime mortar as an inorganic matrix has been proposed as an alternative to cement-based mortars when historic compatibility with the substrate is strictly required, as in case of restoration of historic buildings. In this paper, the effectiveness of a fabric made of basalt fibers embedded in lime mortar matrix (Basalt-FRLM for the strengthening of masonry arches is investigated. An experimental investigation was performed on 1:2 scaled brick masonry arches strengthened at the extrados with a layer of Basalt-FRLM and tested under vertical load. The results obtained are compared with previous results obtained by the authors by testing masonry arches strengthened at their extrados with FRCM and FRP composites. This investigation highlights the effectiveness of Basalt-FRLM in increasing load

  12. Strengthening of metallic alloys with nanometer-size oxide dispersions

    Science.gov (United States)

    Flinn, John E.; Kelly, Thomas F.

    1999-01-01

    Austenitic stainless steels and nickel-base alloys containing, by wt. %, 0.1 to 3.0% V, 0.01 to 0.08% C, 0.01 to 0.5% N, 0.05% max. each of Al and Ti, and 0.005 to 0.10% O, are strengthened and ductility retained by atomization of a metal melt under cover of an inert gas with added oxygen to form approximately 8 nanometer-size hollow oxides within the alloy grains and, when the alloy is aged, strengthened by precipitation of carbides and nitrides nucleated by the hollow oxides. Added strengthening is achieved by nitrogen solid solution strengthening and by the effect of solid oxides precipitated along and pinning grain boundaries to provide temperature-stabilization and refinement of the alloy grains.

  13. Practical approaches to implementing facility wide equipment strengthening programs

    International Nuclear Information System (INIS)

    Kincaid, R.H.; Smietana, E.A.

    1989-01-01

    Equipment strengthening programs typically focus on components required to ensure operability of safety related equipment or to prevent the release of toxic substances. Survival of non-safety related equipment may also be crucial to ensure rapid recovery and minimize business interruption losses. Implementing a strengthening program for non-safety related equipment can be difficult due to the large amounts of equipment involved and limited budget availability. EQE has successfully implemented comprehensive equipment strengthening programs for a number of California corporations. Many of the lessons learned from these projects are applicable to DOE facilities. These include techniques for prioritizing equipment and three general methodologies for anchoring equipment. Pros and cons of each anchorage approach are presented along with typical equipment strengthening costs

  14. Strengthening of metallic alloys with nanometer-size oxide dispersions

    Science.gov (United States)

    Flinn, J.E.; Kelly, T.F.

    1999-06-01

    Austenitic stainless steels and nickel-base alloys containing, by wt. %, 0.1 to 3.0% V, 0.01 to 0.08% C, 0.01 to 0.5% N, 0.05% max. each of Al and Ti, and 0.005 to 0.10% O, are strengthened and ductility retained by atomization of a metal melt under cover of an inert gas with added oxygen to form approximately 8 nanometer-size hollow oxides within the alloy grains and, when the alloy is aged, strengthened by precipitation of carbides and nitrides nucleated by the hollow oxides. Added strengthening is achieved by nitrogen solid solution strengthening and by the effect of solid oxides precipitated along and pinning grain boundaries to provide temperature-stabilization and refinement of the alloy grains. 20 figs.

  15. Polycrystalline strengthening

    DEFF Research Database (Denmark)

    Hansen, Niels

    1985-01-01

    for the understanding of polycrystalline strengthening is obtained mainly from surface relief patterns and from bulk structures observed by transmission electron microscopy of thin foils. The results obtained by these methods are discussed and correlations are proposed. A number of features characterizing the deformed...... structure are summarized and the behavior of a number of metals and alloys is reviewed with emphasis on the structural changes in the interior of the grains and in the vicinity of the grain boundaries. The models for strain accommodation during deformation are discussed on the basis of the microstructures...

  16. Stretch independent regulation of prostaglandin E(2) production within the isolated guinea-pig lamina propria.

    Science.gov (United States)

    Nile, Christopher J; de Vente, Jan; Gillespie, James I

    2010-02-01

    To use an isolated preparation of the guinea-pig bladder lamina propria (LP) to investigate the effects of adenosine tri-phosphate (ATP) and nitric oxide (NO) on the release of prostaglandin E(2) (PGE(2)). The bladders of female guinea-pigs (200-400 g) were isolated and opened to expose the urothelial surface. The LP was dissected free of the underlying detrusor muscle and cut into strips from the dome to base. Strips were then incubated in Krebs buffer at 37 degrees C. Each tissue piece was then exposed to the stable ATP analogue, BzATP, and a NO donor, diethylamine-NONOate (DEANO), and the effect on PGE(2) output into the supernatant determined using the Parameter(TM) PGE(2) enzyme immunoassay kit (R & D Systems, Abingdon, UK). Experiments were repeated in the presence of purinergic receptor and cyclooxygenase (COX) enzymes, COX I and COX II, antagonists. The cellular location of COX I, COX II and neuronal NO synthase (nNOS) within the bladder LP was also determined by immunohistochemistry. PGE(2) production was significantly increased by BzATP. Antagonist studies showed the purinergic stimulation involved both P(2)X and P(2)Y receptors. The BzATP response was inhibited by the COX inhibitor indomethacin (COX I >COX II) but not by DUP 697 (COX II >COX I). Thus, BzATP stimulation occurs because of COX I stimulation. NO had no effect on PGE(2) production over the initial 10 min of an exposure. However, PGE(2) output was increased 100 min after exposure to the NO donor. In the presence of NO, the BzATP stimulation was abolished. Immunohistochemistry was used to confirm the location of COX I to the basal and inner intermediate urothelial layers and to cells within the diffuse layer of LP interstitial cells. In addition, nNOS was also located in the basal urothelial layers whilst COX II was found in the interstitial cell layers. There is complex interaction between ATP and NO to modulate PGE(2) release from the bladder LP in the un-stretched preparation. Such

  17. RC T beams strengthened to shear with carbon fiber composites

    Directory of Open Access Journals (Sweden)

    L. A. Spagnolo JR

    Full Text Available This paper presents the experimental data of the behavior of reinforced concrete beams strengthened to shear with carbon fiber composites. The tests were composed of eight T beams, b w=15 cm, h=40 cm, flange width 40 cm, flange height 8 cm, and length 300 cm, divided into two series with the same longitudinal steel reinforcement and a reference beam without strengthening in each series. The beams had two types of arrangement of internal steel stirrups. The test variables were the internal and external geometric ratio of the transverse reinforcement and the mechanical ratio of carbon fiber composites stirrups. All the beams were loaded at two points. The strengthened beams were submitted to a preloading and the strengthening was applied to the cracked beam. All the beams were designed in order to guarantee shear failure, and the ultimate load of the strengthened beams was 36% to 54% greater than the reference beams. The Cracking Sliding Model applied to the strengthened beams was evaluated and showed good agreement with the experimental results.

  18. Nanostructured thin film coatings with different strengthening effects

    Directory of Open Access Journals (Sweden)

    Panfilov Yury

    2017-01-01

    Full Text Available A number of articles on strengthening thin film coatings were analyzed and a lot of unusual strengthening effects, such as super high hardness and plasticity simultaneously, ultra low friction coefficient, high wear-resistance, curve rigidity increasing of drills with small diameter, associated with process formation of nanostructured coatings by the different thin film deposition methods were detected. Vacuum coater with RF magnetron sputtering system and ion-beam source and arc evaporator for nanostructured thin film coating manufacture are represented. Diamond Like Carbon and MoS2 thin film coatings, Ti, Al, Nb, Cr, nitride, carbide, and carbo-nitride thin film materials are described as strengthening coatings.

  19. Structural improvement of strengthened deck panels with externally bonded plates

    International Nuclear Information System (INIS)

    Sim, Jongsung; Oh, Hongseob

    2005-01-01

    Concrete bridge decks require eventual replacement and rehabilitation due to decreasing load-carrying capacity. This paper compares different strengthening design procedures that improve the usability and structural performance of bridge decks. The failure characteristics of bridge decks strengthened with various materials such as carbon fiber sheet, glass fiber sheet, steel plate, and grid CFRP and GFRP are analyzed, and the theoretical load-carrying capacities are evaluated using traditional beam and yield line theory, and punching shear analysis. The strengthening materials increase the punching shear strength of the deck and change the failure mode of the strengthened panel

  20. Electron-microscopic investigations of dispersion-strengthened superalloys

    International Nuclear Information System (INIS)

    Schroeder, J.H.; Arzt, E.

    1988-01-01

    Oxide dispersion strengthened (ODS) superalloys possess a high creep strength up to temperatures above 1000 0 C. This is due to a fine dispersion of incoherent Y 2 O 3 particles in connection with a highly elongated grain structure. To investigate the production and properties of ODS alloys, the grain structure was studied and the shape and distribution of dispersoids were characterized after each of the various production steps. Because the interactions between lattice dislocations and dispersoids control the deformation behaviour at high temperatures, the dislocation-dispersoid configurations in crept specimens have been studied by a TEM stereo technique and under weak-beam conditions. It was possible to detect strain fields around the dispersoids using TEM. The results lead to an improved understanding of dispersion strengthening at high temperatures and provide guidelines for the optimum use of this strengthening mechanism. (orig.) [de

  1. Structural Parameters and Strengthening Mechanisms in Cold-Drawn Pearlitic Steel Wires

    DEFF Research Database (Denmark)

    Zhang, Xiaodan; Godfrey, Andy; Huang, Xiaoxu

    2012-01-01

    Pearlitic steel wires have a nanoscale structure and a strength which can reach 5 GPa. In order to investigate strengthening mechanisms, structural parameters including interlamellar spacing, dislocation density and cementite decomposition, have been analyzed by transmission electron microscopy...... and high resolution electron microscopy in wires cold drawn up to a strain of 3.7. Three strengthening mechanisms, namely boundary strengthening, dislocation strengthening and solid solution hardening have been analyzed and good agreement has been found between the measured flow stress and the value...

  2. Initial Semantics for Strengthened Signatures

    Directory of Open Access Journals (Sweden)

    André Hirschowitz

    2012-02-01

    Full Text Available We give a new general definition of arity, yielding the companion notions of signature and associated syntax. This setting is modular in the sense requested by Ghani and Uustalu: merging two extensions of syntax corresponds to building an amalgamated sum. These signatures are too general in the sense that we are not able to prove the existence of an associated syntax in this general context. So we have to select arities and signatures for which there exists the desired initial monad. For this, we follow a track opened by Matthes and Uustalu: we introduce a notion of strengthened arity and prove that the corresponding signatures have initial semantics (i.e. associated syntax. Our strengthened arities admit colimits, which allows the treatment of the λ-calculus with explicit substitution.

  3. South-South cooperation as a mechanism to strengthen public ...

    African Journals Online (AJOL)

    South-South cooperation as a mechanism to strengthen public health services in Africa: ... PROMOTING ACCESS TO AFRICAN RESEARCH ... Implementation of new models of development cooperation have been on the increase ... health system strengthening, aid effectiveness, sustainable development goals, Africa ...

  4. ESTIMATION OF SUBGRADE STRENGTHENING INFLUENCE USING SOILCEMENT ELEMENTS

    Directory of Open Access Journals (Sweden)

    V. D. Petrenko

    2016-08-01

    Full Text Available Purpose. The aim of this work is to identify dependencies and options to strengthen the roadbed and a weak base by grouting piles. Analysis of software package SCAD to assess the effect of the selected option of strengthening the construction of spatial subgrade models. Methodology. In this paper the method of calculation of the soil mass in the software package SCAD is considered, which is a universal accounting system of finite-element analysis of structures and is focused on solving problems of designing buildings and structures rather complex structure. The finite element method is among the most modern and effective methods for the calculation of structures for various purposes. In the simulation, we get a complete picture of the stress-strain state of the study area, as well as the value of the limit load, rainfall, and so on. The spatial model based on the finite element volume, to better address the real characteristics of the soil mass, meets all the geometric characteristics of size and natural subgrade and the top structure the path that has been adopted in Ukraine. Findings. It was found that the most effective option to strengthen the roadbed, when applying grouting piles at the base of the subgrade and body, is to strengthen the five piles. At the same time there is even strengthen the soil mass at the level of 25 … 30% of the entire depth. However, even with the strengthening of the only two piles at the base of the effect of the strengthening of 14.1%. Established equation is linear and describes the decrease in strain. Taking into account the results of the research can be concluded that the consolidation is proportional to the depth with any number of piles. The dependence of the strain on the number of piles adheres to a polynomial function. Strengthening the bases of the subgrade and body depth also occurs in proportion with any number of piles. Originality. Design scheme generation algorithm for the calculation of the

  5. Changes in the interstitial cells of Cajal and neuronal nitric oxide synthase positive neuronal cells with aging in the esophagus of F344 rats.

    Directory of Open Access Journals (Sweden)

    Hee Jin Kim

    Full Text Available The aging-associated cellular and molecular changes in esophagus have not been established, yet. Thus we evaluated histological structure, interstitial cells of Cajal (ICCs, neuronal nitric oxide synthase (nNOS-positive cells, and contractility in the esophagus of Fischer 344 rat at different ages (6-, 31-, 74-weeks, and 2-years. The lamina propria thickness and endomysial area were calculated. The immunoreactivity of c-Kit, nNOS and protein gene product (PGP 9.5 was counted after immunohistochemistry. Expression of c-Kit, stem cell factor (SCF, nNOS and PGP 9.5 mRNA was measured by real-time PCR, and expression of c-Kit and nNOS protein was detected by Western blot. Isovolumetric contractile force measurement and electrical field stimulation (EFS were conducted. The lamina propria thickness increased (6 week vs 2 year, P = 0.005 and the endomysial area of longitudinal muscle decreased with aging (6 week vs 2 year, P<0.001, while endomysial area of circular muscle did not significantly decrease. The proportions of NOS-immunoreactive cells and c-Kit-immunoreactive areas declined with aging (6 week vs 2 year; P<0.001 and P = 0.004, respectively, but there was no significant change of PGP 9.5-immunopositiviy. The expressions of nNOS, c-Kit and SCF mRNA also reduced with aging (6 week vs 2 year; P = 0.006, P = 0.001 and P = 0.006, respectively, while the change of PGP 9.5 mRNA expression was not significant. Western blot showed the significant decreases of nNOS and c-Kit protein expression with aging (6 week vs 2 year; P = 0.008 and P = 0.012, respectively. The EFS-induced esophageal contractions significantly decreased in 2-yr-old rat compared with 6-wk-old rats, however, L-NG-Nitroarginine methylester did not significantly increase the spontaneous and EFS-induced contractions in the 6-wk- and 2-yr-old rat esophagus. In conclusion, an increase of lamina propria thickness, a decrease of endomysial area, c-Kit, SCF and NOS expression with preserved

  6. Behavior of masonry strengthened infilled reinforced concrete frames under in-plane load

    Directory of Open Access Journals (Sweden)

    Lila M. Abdel-Hafez

    2015-08-01

    The ductility of infilled frame strengthened with ferrocement was the best of all strengthened frames, while strengthening with GFRP increases its ultimate load carrying capacity but reduces its ductility.

  7. Dislocation Strengthening without Ductility Trade-off in Metastable Austenitic Steels

    Science.gov (United States)

    Liu, Jiabin; Jin, Yongbin; Fang, Xiaoyang; Chen, Chenxu; Feng, Qiong; Liu, Xiaowei; Chen, Yuzeng; Suo, Tao; Zhao, Feng; Huang, Tianlin; Wang, Hongtao; Wang, Xi; Fang, Youtong; Wei, Yujie; Meng, Liang; Lu, Jian; Yang, Wei

    2016-10-01

    Strength and ductility are mutually exclusive if they are manifested as consequence of the coupling between strengthening and toughening mechanisms. One notable example is dislocation strengthening in metals, which invariably leads to reduced ductility. However, this trend is averted in metastable austenitic steels. A one-step thermal mechanical treatment (TMT), i.e. hot rolling, can effectively enhance the yielding strength of the metastable austenitic steel from 322 ± 18 MPa to 675 ± 15 MPa, while retaining both the formability and hardenability. It is noted that no boundaries are introduced in the optimized TMT process and all strengthening effect originates from dislocations with inherited thermal stability. The success of this method relies on the decoupled strengthening and toughening mechanisms in metastable austenitic steels, in which yield strength is controlled by initial dislocation density while ductility is retained by the capability to nucleate new dislocations to carry plastic deformation. Especially, the simplicity in processing enables scaling and industrial applications to meet the challenging requirements of emissions reduction. On the other hand, the complexity in the underlying mechanism of dislocation strengthening in this case may shed light on a different route of material strengthening by stimulating dislocation activities, rather than impeding motion of dislocations.

  8. Illustration of extensive extracellular matrix at the epithelial-mesenchymal interface within the renal stem/progenitor cell niche

    Directory of Open Access Journals (Sweden)

    Minuth Will W

    2012-09-01

    Full Text Available Abstract Background Stem/progenitor cells are promising candidates to treat diseased renal parenchyma. However, implanted stem/progenitor cells are exposed to a harmful atmosphere of degenerating parenchyma. To minimize hampering effects after an implantation investigations are in progress to administer these cells within an artificial polyester interstitum supporting survival. Learning from nature the renal stem/progenitor cell niche appears as a valuable model. At this site epithelial stem/progenitor cells within the collecting duct ampulla face mesenchymal stem/progenitor cells. Both cell types do not have close contact but are separated by a wide interstitium. Methods To analyze extracellular matrix in this particular interstitium, special contrasting for transmission electron microscopy was performed. Kidneys of neonatal rabbits were fixed in solutions containing glutaraldehyde (GA or in combination with cupromeronic blue, ruthenium red and tannic acid. Results GA revealed a basal lamina at the ampulla and a bright but inconspicuously looking interstitial space. In contrast, GA containing cupromeronic blue exhibits numerous proteoglycan braces lining from the ampulla towards the interstitial space. GA containing ruthenium red or tannic acid demonstrates clouds of extracellular matrix protruding from the basal lamina of the ampulla to the surface of mesenchymal stem/progenitor cells. Conclusions The actual data show that the interstitium between epithelial and mesenchymal stem/progenitor cells contains much more and up to date unknown extracellular matrix than earlier observed by classical GA fixation.

  9. Increased angiotensin II type 1 receptor expression in temporal arteries from patients with giant cell arteritis

    DEFF Research Database (Denmark)

    Dimitrijevic, Ivan; Malmsjö, Malin; Andersson, Christina

    2009-01-01

    PURPOSE: Currently, giant cell arteritis (GCA) is primarily treated with corticosteroids or immunomodulating agents, but there is interest in identifying other noncorticosteroid alternatives. Similarities exist in the injury pathways between GCA and atherosclerosis. Angiotensin II is a vasoactive......, internal elastic lamina degeneration, and band-shaped infiltrates of inflammatory cells, including lymphocytes, histocytes, and multinucleated giant cells. AT(1) receptor staining was primarily observed in the medial layer of the temporal arteries and was higher in the patients with GCA than in the control...

  10. High-Strength Low-Alloy Steel Strengthened by Multiply Nanoscale Microstructures

    Science.gov (United States)

    Shen, Y. F.; Zuo, L.

    Recently, we have being focused on improving the strength without sacrificing ductility of High-strength low-alloy (HSLA) steels by designing nanostructures. Several developments have been obtained, summarized as the following three parts: (a) Depressively nanoscale precipitates: A ferritic steel with finely dispersed precipitates reveals a yield strength of 760 MPa, approximately three times higher than that of conventional Ti-bearing high strength hot-rolled sheet steels, and its ultimate tensile strength reaches 850 MPa with an elongation-to-failure value of 18%. The finely dispersed TiC precipitates in the matrix provide matrix strengthening. The estimated magnitude of precipitation strengthening is around 458 MPa. The effects of the particle size, particle distribution and intrinsic particle strength have been investigated through dislocation dynamics (DD) simulations. The DD results show that strengthening is not only a function of the density of the nano-scale precipitates but also of their size. (b) Ultrafinely ferritic plate: An interstitial-free (IF) steel sheet with a cold-rolling reduction of 75% shows a high tensile strength (710MPa) while preserving a considerable plastic strain (13%). The ductility recovery with increasing the rolling reduction up to 75% is related with the decreasing both in lamellar spacings and cell blocks sizes. (c) Parallel nano-laminated austenite: A composite microstructure consisting of ferrite, bainitic ferrite (BF) laths and retained austenite (RA) platelets has been found for the steel with a chemical composition of 0.19C-0.30Si-1.76Mn-1.52Al (in mass fraction), processed with annealing and bainitic holding. The sample annealed at 820oC (for 120s) and partitioned at 400oC (for 300s) has the best combination of ultimate tensile strength (UTS, 682 MPa) and elongation to failure ( 70%) with about 26% of BF plates 16% RA in its microstructure.

  11. Galectin-3 and N-acetylglucosamine promote myogenesis and improve skeletal muscle function in the mdx model of Duchenne muscular dystrophy.

    Science.gov (United States)

    Rancourt, Ann; Dufresne, Sébastien S; St-Pierre, Guillaume; Lévesque, Julie-Christine; Nakamura, Haruka; Kikuchi, Yodai; Satoh, Masahiko S; Frenette, Jérôme; Sato, Sachiko

    2018-06-12

    The muscle membrane, sarcolemma, must be firmly attached to the basal lamina. The failure of proper attachment results in muscle injury, which is the underlying cause of Duchenne muscular dystrophy (DMD), in which mutations in the dystrophin gene disrupts the firm adhesion. In patients with DMD, even moderate contraction causes damage, leading to progressive muscle degeneration. The damaged muscles are repaired through myogenesis. Consequently, myogenesis is highly active in patients with DMD, and the repeated activation of myogenesis leads to the exhaustion of the myogenic stem cells. Therefore, approaches to reducing the risk of the exhaustion are to develop a treatment that strengthens the interaction between the sarcolemma and the basal lamina and increases the efficiency of the myogenesis. Galectin-3 is an oligosaccharide-binding protein and is known to be involved in cell-cell interactions and cell-matrix interactions. Galectin-3 is expressed in myoblasts and skeletal muscle, although its function in muscle remains elusive. In this study, we found evidence that galectin-3 and the monosaccharide N-acetylglucosamine, which increases the synthesis of binding partners (oligosaccharides) of galectin-3, promote myogenesis in vitro. Moreover, in the mdx mouse model of DMD, treatment with N-acetylglucosamine increased muscle-force production. The results suggest that treatment with N-acetylglucosamine might mitigate the burden of DMD.-Rancourt, A., Dufresne, S. S., St-Pierre, G., Lévesque, J.-C., Nakamura, H., Kikuchi, Y., Satoh, M. S., Frenette, J., Sato, S. Galectin-3 and N-acetylglucosamine promote myogenesis and improve skeletal muscle function in the mdx model of Duchenne muscular dystrophy.

  12. Interactions between intraspinal Schwann cells and the cellular constituents normally occurring in the spinal cord: an ultrastructural study in the irradiated rat

    International Nuclear Information System (INIS)

    Sims, T.J.; Gilmore, S.A.

    1983-01-01

    Relationships between intraspinal Schwann cells and neuroglia, particularly astrocytes, were studied following X-irradiation of the spinal cord in 3-day old rats. Initially, this exposure results in a depletion of the neuroglial population. By 10 days post-irradiation (P-I), gaps occur in the glia limitans, although the overlying basal lamina remains intact. Development of and myelination by intraspinal Schwann cells is well underway by 15 days P-I. These Schwann cell-occupied regions have a paucity of astrocyte processes, a finding which persists throughout the study (60 days P-I), and several types of Schwann cell-neuroglial interfaces are observed. The gaps in the glia limitans widen as the P-I interval increases. At 45 and 60 days P-I, the basal lamina no longer forms a singular, continuous covering over the spinal cord surface, but follows instead a rather tortuous course over the disrupted glia limitans and the intraspinal Schwann cells. Although the mode of initial occurrence of Schwann cells within the spinal cord is not yet understood, the data indicate that the astrocyte population is involved in that process, as well as in limiting the further development of Schwann cells within the substance of the spinal cord. (Auth.)

  13. In vitro evaluation of a basic fibroblast growth factor-containing hydrogel toward vocal fold lamina propria scar treatment.

    Science.gov (United States)

    Erndt-Marino, Josh D; Jimenez-Vergara, Andrea C; Diaz-Rodriguez, Patricia; Kulwatno, Jonathan; Diaz-Quiroz, Juan Felipe; Thibeault, Susan; Hahn, Mariah S

    2018-04-01

    Scarring of the vocal fold lamina propria can lead to debilitating voice disorders that can significantly impair quality of life. The reduced pliability of the scar tissue-which diminishes proper vocal fold vibratory efficiency-results in part from abnormal extracellular matrix (ECM) deposition by vocal fold fibroblasts (VFF) that have taken on a fibrotic phenotype. To address this issue, bioactive materials containing cytokines and/or growth factors may provide a platform to transition fibrotic VFF within the scarred tissue toward an anti-fibrotic phenotype, thereby improving the quality of ECM within the scar tissue. However, for such an approach to be most effective, the acute host response resulting from biomaterial insertion/injection likely also needs to be considered. The goal of the present work was to evaluate the anti-fibrotic and anti-inflammatory capacity of an injectable hydrogel containing tethered basic fibroblast growth factor (bFGF) in the dual context of scar and biomaterial-induced acute inflammation. An in vitro co-culture system was utilized containing both activated, fibrotic VFF and activated, pro-inflammatory macrophages (MΦ) within a 3D poly(ethylene glycol) diacrylate (PEGDA) hydrogel containing tethered bFGF. Following 72 h of culture, alterations in VFF and macrophage phenotype were evaluated relative to mono-culture and co-culture controls. In our co-culture system, bFGF reduced the production of fibrotic markers collagen type I, α smooth muscle actin, and biglycan by activated VFF and promoted wound-healing/anti-inflammatory marker expression in activated MΦ. Cumulatively, these data indicate that bFGF-containing hydrogels warrant further investigation for the treatment of vocal fold lamina propria scar. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1258-1267, 2018. © 2017 Wiley Periodicals, Inc.

  14. The nanostructure of myoendothelial junctions contributes to signal rectification between endothelial and vascular smooth muscle cells

    DEFF Research Database (Denmark)

    Brasen, Jens Christian; Jacobsen, Jens Christian Brings; von Holstein-Rathlou, Niels-Henrik

    2012-01-01

    Micro-anatomical structures in tissues have potential physiological effects. In arteries and arterioles smooth muscle cells and endothelial cells are separated by the internal elastic lamina, but the two cell layers often make contact through micro protrusions called myoendothelial junctions. Cross...... types and the myoendothelial junction. The model is implemented as a 2D axi-symmetrical model and solved using the finite element method. We have simulated diffusion of Ca(2+) and IP(3) between the two cell types and we show that the micro-anatomical structure of the myoendothelial junction in itself...

  15. On the superposition of strengthening mechanisms in dispersion strengthened alloys and metal-matrix nanocomposites: Considerations of stress and energy

    Science.gov (United States)

    Ferguson, J. B.; Schultz, Benjamin F.; Venugopalan, Dev; Lopez, Hugo F.; Rohatgi, Pradeep K.; Cho, Kyu; Kim, Chang-Soo

    2014-03-01

    Yield strength improvement in dispersion strengthened alloys and nano particle-reinforced composites by well-known strengthening mechanisms such as solid solution, grain refinement, coherent and incoherent dispersed particles, and increased dislocation density resulting from work-hardening can all be described individually. However, there is no agreed upon description of how these mechanisms combine to determine the yield strength. In this work, we propose an analytical yield strength prediction model combining arithmetic and quadratic addition approaches based on the consideration of two types of yielding mechanisms; stress-activated and energy-activated. Using data available in the literature for materials of differing grain sizes, we consider the cases of solid solutions and coherent precipitates to show that they follow stress-activated behavior. Then, we applied our model with some empirical parameters to precipitationhardenable materials of various grain sizes in both coherent and incoherent precipitate conditions, which demonstrated that grain boundary and Orowan-strengthening can be treated as energy-activated mechanisms.

  16. Strengthening Leadership Competencies of Thai Secondary School Teachers

    OpenAIRE

    Chaiyot Wanutha; Kowat Tesaputa; Anan Sri-Ampai

    2017-01-01

    The research aimed 1) to investigate components and indicators of the leadership competencies of secondary school teachers, 2) to explore the existing situations and desirable situations of secondary school teachers’ leadership competencies, 3) to study the techniques to strengthen teachers’ leadership competencies, 4) to develop the teacher-leadership competencies strengthening program, and 5) to find out the results of implementing the program to improve the teacher’s ...

  17. Direct dorsal hippocampal-prelimbic cortex connections strengthen fear memories.

    Science.gov (United States)

    Ye, Xiaojing; Kapeller-Libermann, Dana; Travaglia, Alessio; Inda, M Carmen; Alberini, Cristina M

    2017-01-01

    The ability to regulate the consolidation and strengthening of memories for threatening experiences is critical for mental health, and its dysregulation may lead to psychopathologies. Re-exposure to the context in which the threat was experienced can either increase or decrease fear response through distinct processes known, respectively, as reconsolidation or extinction. Using a context retrieval-dependent memory-enhancement model in rats, we report that memory strengthens through activation of direct projections from dorsal hippocampus to prelimbic (PL) cortex and activation of critical PL molecular mechanisms that are not required for extinction. Furthermore, while sustained PL brain-derived neurotrophic factor (BDNF) expression is required for memory consolidation, retrieval engages PL BDNF to regulate excitatory and inhibitory synaptic proteins neuroligin 1 and neuroligin 2, which promote memory strengthening while inhibiting extinction. Thus, context retrieval-mediated fear-memory enhancement results from a concerted action of mechanisms that strengthen memory through reconsolidation while suppressing extinction.

  18. Differential effect of immune cells on non-pathogenic Gram-negative bacteria-induced nuclear factor-kappaB activation and pro-inflammatory gene expression in intestinal epithelial cells

    DEFF Research Database (Denmark)

    Haller, D.; Holt, L.; Parlesak, Alexandr

    2004-01-01

    stimulation, interleukin-8 (IL-8) mRNA accumulation is strongly induced in Escherichia coli- but not Bacteroides vulgatus-stimulated IEC cocultured with peripheral blood (PBMC) and lamina propria mononuclear cells (LPMC). The presence of PBMC triggered both E. coli- and B. vulgatus-induced mRNA expression...... in the presence of PBMC. Interestingly, B. vulgatus- and E. coli-derived lipopolysaccharide-induced similar IL-8 mRNA expression in epithelial cells after basolateral stimulation of HT-29/PBMC cocultures. Although luminal enteric bacteria have adjuvant and antigenic properties in chronic intestinal inflammation...

  19. Towards Rational Design Method for Strengthening of Concrete Structures by External Bonding

    Directory of Open Access Journals (Sweden)

    Furuuchi H.

    2012-01-01

    Full Text Available Many infrastructures need to be repaired or strengthened due to various reasons, such as unexpected deterioration and changes in performance requirement. This paper presents the following recent achievements by the authors’ group on design method for flexural strengthening of concrete structures by external bonding; (i fracture characteristics of interface between substrate concrete and cementitious overlay, (ii crack spacing of flexural strengthened beams, which affects debonding strength, (iii strengths of intermediate crack (IC debonding and end peeling, (iv strength of concrete cover separation, and (v effectiveness of strengthening by external bonding. A unified approach for flexural strengthening by steel plate, fiber reinforced polymer lami¬nate and cementitious overlay, for both intermediate crack (IC debonding, including end peeling, and concrete cover separation is pre¬sented with consideration of crack spacing in the streng¬thened members. Appropriate interfacial rough¬¬¬ness to achieve efficient interface bond property is clari¬fied and the concept of effectiveness of strengthen¬ing is proposed for better strengthening design.

  20. Bonding techniques for flexural strengthening of R.C. beams using CFRP laminates

    Directory of Open Access Journals (Sweden)

    Alaa Morsy

    2013-09-01

    Full Text Available This paper presents an experimental study of an alternative method of attaching FRP laminates to reinforced concrete beams by the way of fasting steel rivets through the FRP laminate and concrete substrate. Five full scale R.C. beams were casted and strengthened in flexural using FRP laminate bonded with conventional epoxy and compared with other beams strengthened with FRP laminate and bonded with fastener “steel rivets” of 50 mm length and 10 mm diameter. Based on experimental evidence the beam strengthened with conventional bonding methods failed due to de-bonding with about 13% increase over the un-strengthened beam. On the other hand, the beams strengthened with FRP laminate and bonded by four steel fastener rivets only failed by de-bonding also but at higher flexural capacity with increase 19% over the un-strengthened beam.

  1. Shear Strengthening of Concrete Structures with the use of mineral based composites

    DEFF Research Database (Denmark)

    Blanksvärd, Thomas; Täljsten, Björn; Carolin, Anders

    2009-01-01

    concrete (RC) beams strengthened in shear with the use of cementitious bonding agents and carbon fiber grids, denoted mineral based composites (MBC). In this study it is shown that the MBC system has a strengthening effect corresponding to that of strengthening systems using epoxy bonding agents and carbon...... for rehabilitation. In addition, more traffic and heavier loads lead to the need for upgrading. Existing externally bonded strengthening systems using FRP (fiber reinforced polymers) and epoxy as bonding agents have been proven to be a good approach to repair and strengthen concrete structures. However, the use...... fiber sheets. Different designs and material properties of the MBC system have been tested. An extensive monitoring set-up has been carried out using traditional strain gauges and photometric strain measurements to obtain strains in steel reinforcement, in FRP and strain fields on the strengthened...

  2. FRP strengthening of RC walls with openings

    DEFF Research Database (Denmark)

    Hansen, Christian Skodborg; Sas, Gabriel; Täljsten, Björn

    2009-01-01

    Strengthening reinforced concrete (RC) walls with openings using fibre reinforced polymers (FRP) has been experimentally proven to be a viable rehabilitation method. However, very few theoretical investigations are reported. In this paper two methods of analysis are presented. Since openings vary...... in size, the analysis of a strengthened wall can be divided into frame idealization method for large openings, and combined disk and frame analysis for smaller openings. The first method provides an easy to use tool in practical engineering, where the latter describes the principles of a ductile...

  3. Experimental Investigation on Strengthening of Bolted Connections in Transmission/Communication Towers

    Science.gov (United States)

    Balagopal, R.; Prasad Rao, N.; Rokade, R. P.; Umesha, P. K.

    2018-02-01

    Due to increase in demand for power supply and increase in bandwidth for communication industry, the existing transmission line (TL) and communication towers needs to be strengthened. The strengthening of existing tower is economical rather than installation of new towers due to constraints in acquisition of land. The size of conductors have to be increased or additional number of antenna needs to be installed in existing TL/communication tower respectively. The compression and tension capacity of members in the existing towers have to be increased to sustain the additional loads due to wind and self-weight of these components. The tension capacity enhancement of existing angle sections in live line condition without power shut-down is a challenging task. In the present study, the use of Glass Fiber Reinforced Plastic (GFRP) plate/angle sections is explored to strengthen existing bolted connections in TL/communication towers. Experimental investigation conducted at component level on strengthening of existing two types of single cover steel butt joint, one made of steel plate and another joint made of steel angle sections respectively. First series of experiment conducted on strengthening the connection using GFRP plate/cleat angle sections. The second series of strengthening experiment is conducted using steel plate/angle sections to replace GFRP sections. The load sharing behaviour of strengthened GFRP and steel section is compared and suitable recommendations are given.

  4. Experimental Investigation on Strengthening of Bolted Connections in Transmission/Communication Towers

    Science.gov (United States)

    Balagopal, R.; Prasad Rao, N.; Rokade, R. P.; Umesha, P. K.

    2018-06-01

    Due to increase in demand for power supply and increase in bandwidth for communication industry, the existing transmission line (TL) and communication towers needs to be strengthened. The strengthening of existing tower is economical rather than installation of new towers due to constraints in acquisition of land. The size of conductors have to be increased or additional number of antenna needs to be installed in existing TL/communication tower respectively. The compression and tension capacity of members in the existing towers have to be increased to sustain the additional loads due to wind and self-weight of these components. The tension capacity enhancement of existing angle sections in live line condition without power shut-down is a challenging task. In the present study, the use of Glass Fiber Reinforced Plastic (GFRP) plate/angle sections is explored to strengthen existing bolted connections in TL/communication towers. Experimental investigation conducted at component level on strengthening of existing two types of single cover steel butt joint, one made of steel plate and another joint made of steel angle sections respectively. First series of experiment conducted on strengthening the connection using GFRP plate/cleat angle sections. The second series of strengthening experiment is conducted using steel plate/angle sections to replace GFRP sections. The load sharing behaviour of strengthened GFRP and steel section is compared and suitable recommendations are given.

  5. FIRE PROTECTION OF TIMBER STRUCTURES STRENGTHENED WITH FRP MATERIALS

    Directory of Open Access Journals (Sweden)

    Radek Zigler

    2015-12-01

    Full Text Available Modern, progressive methods of structures’ strengthening based on the use of composite materials composed of high strength fibers (carbon, glass, aramid or basalt and matrices based on epoxy resins brings, among many indisputable advantages (low weight, high effectiveness, easy application etc. also some disadvantages. One of the major disadvantages is a low fire resistance of these materials due to the low glass transition temperature Tg of the resin used. Based on an extensive research of strengthening of historic structures with FRP materials [1], the article outlines possible approaches to this problem, especially while strengthening timber load- bearing structures of historic buildings.

  6. Strengthening the sports data infrastructure

    NARCIS (Netherlands)

    Annet Tiessen-Raaphorst; Jos de Haan; with contributions from Remco van den Dool

    2012-01-01

    Original title: Versterking data-infrastructuur sport Sports research in the Netherlands has developed rapidly over the last ten years; strengthening the data infrastructure will facilitate its further growth in the future. Currently, however, there is no clear overall picture of the available

  7. Behaviour of Strengthened RC Frames with Eccentric Steel Braced Frames

    Science.gov (United States)

    Kamanli, Mehmet; Unal, Alptug

    2017-10-01

    After devastating earthquakes in recent years, strengthening of reinforced concrete buildings became an important research topic. Reinforced concrete buildings can be strengthened by steel braced frames. These steel braced frames may be made of concentrically or eccentrically indicated in Turkish Earthquake Code 2007. In this study pushover analysis of the 1/3 scaled 1 reinforced concrete frame and 1/3 scaled 4 strengthened reinforced concrete frames with internal eccentric steel braced frames were conducted by SAP2000 program. According to the results of the analyses conducted, load-displacement curves of the specimens were compared and evaluated. Adding eccentric steel braces to the bare frame decreased the story drift, and significantly increased strength, stiffness and energy dissipation capacity. In this strengthening method lateral load carrying capacity, stiffness and dissipated energy of the structure can be increased.

  8. Preparation of a new composite combining strengthened β-tricalcium phosphate with platelet-rich plasma as a potential scaffold for the repair of bone defects

    Science.gov (United States)

    WANG, CHENGGONG; ZHONG, DA; ZHOU, XING; YIN, KE; LIAO, QIANDE; KONG, LINGYU; LIU, ANSONG

    2014-01-01

    β-tricalcium phosphate (β-TCP) and platelet-rich plasma (PRP) are commonly used in bone tissue engineering. In the present study, a new composite combining strengthened β-TCP and PRP was prepared and its morphological and mechanical properties were investigated by scanning electron microscopy (SEM) and material testing. The biocompatibility was evaluated by measuring the adhesion rate and cytotoxicity of bone marrow stromal cells (BMSCs). The strengthened β-TCP/PRP composite had an appearance like the fungus Boletus kermesinus with the PRP gel distributed on the surface of the micropores. The maximum load and load intensity were 945.6±86.4 N and 13.1±0.5 MPa, which were significantly higher than those of β-TCP (110.1±14.3 N and 1.6±0.2 MPa; P96% after 24 h, with a cell cytotoxicity value of zero. SEM micrographs revealed that following seeding of BMSCs onto the composite in high-glucose Dulbecco’s modified Eagle’s medium culture for two weeks, the cells grew well and exhibited fusiform, spherical and polygonal morphologies, as well as pseudopodial connections. The strengthened β-TCP/PRP composite has the potential to be used as a scaffold in bone tissue engineering due to its effective biocompatibility and mechanical properties. PMID:25187800

  9. Strengthening Nordic-Baltic Defense Capabilities

    DEFF Research Database (Denmark)

    Breitenbauch, Henrik Ø.

    2014-01-01

    and troubling challenge to the way international security has been structured in Europe since the end of the Cold War. While most of the existing defense cooperation with a view of strengthening defense capabilities has been carried out within the internationally renowned framework of NORDEFCO...

  10. Microstructure and strengthening mechanisms in cold-drawn pearlitic steel wire

    DEFF Research Database (Denmark)

    Zhang, Xiaodan; Godfrey, Andy; Huang, Xiaoxu

    2011-01-01

    Strengthening mechanisms and strength–structure relationships have been analyzed in a cold-drawn pearlitic steel with a structural scale in the nanometer range and a flow stress of about 3.5GPa. The wires have been drawn up to a strain of 3.7 and the structures analyzed and quantified by transmis......Strengthening mechanisms and strength–structure relationships have been analyzed in a cold-drawn pearlitic steel with a structural scale in the nanometer range and a flow stress of about 3.5GPa. The wires have been drawn up to a strain of 3.7 and the structures analyzed and quantified...... by transmission electron microscopy and high resolution electron microscopy. The mechanical properties have been determined by tensile testing. It is found that the interlamellar spacing and the thickness of the cementite lamellae are reduced in accordance with the changes in wire diameter up to a strain of 2...... at the ferrite/cementite interface. Three strengthening mechanisms have been analyzed: (i) boundary strengthening, (ii) dislocation strengthening and (iii) solid solution hardening. The individual and combined contributions, based on an assumption of linear additivity, of these mechanisms to the wire strength...

  11. Cell death in neural precursor cells and neurons before neurite formation prevents the emergence of abnormal neural structures in the Drosophila optic lobe.

    Science.gov (United States)

    Hara, Yusuke; Sudo, Tatsuya; Togane, Yu; Akagawa, Hiromi; Tsujimura, Hidenobu

    2018-04-01

    Programmed cell death is a conserved strategy for neural development both in vertebrates and invertebrates and is recognized at various developmental stages in the brain from neurogenesis to adulthood. To understand the development of the central nervous system, it is essential to reveal not only molecular mechanisms but also the role of neural cell death (Pinto-Teixeira et al., 2016). To understand the role of cell death in neural development, we investigated the effect of inhibition of cell death on optic lobe development. Our data demonstrate that, in the optic lobe of Drosophila, cell death occurs in neural precursor cells and neurons before neurite formation and functions to prevent various developmental abnormalities. When neuronal cell death was inhibited by an effector caspase inhibitor, p35, multiple abnormal neuropil structures arose during optic lobe development-e.g., enlarged or fused neuropils, misrouted neurons and abnormal neurite lumps. Inhibition of cell death also induced morphogenetic defects in the lamina and medulla development-e.g., failures in the separation of the lamina and medulla cortices and the medulla rotation. These defects were reproduced in the mutant of an initiator caspase, dronc. If cell death was a mechanism for removing the abnormal neuropil structures, we would also expect to observe them in mutants defective for corpse clearance. However, they were not observed in these mutants. When dead cell-membranes were visualized with Apoliner, they were observed only in cortices and not in neuropils. These results suggest that the cell death occurs before mature neurite formation. Moreover, we found that inhibition of cell death induced ectopic neuroepithelial cells, neuroblasts and ganglion mother cells in late pupal stages, at sites where the outer and inner proliferation centers were located at earlier developmental stages. Caspase-3 activation was observed in the neuroepithelial cells and neuroblasts in the proliferation centers

  12. Clinical Assessment of Lamina Cribrosa Curvature in Eyes with Primary Open-Angle Glaucoma.

    Directory of Open Access Journals (Sweden)

    Yong Woo Kim

    Full Text Available Quantitative evaluation of lamina cribrosa (LC posterior bowing in primary open-angle glaucoma (POAG eyes using swept-source optical coherence tomography.Patients with POAG (n = 123 eyes and healthy individuals of a similar age (n = 92 eyes were prospectively recruited. Anterior laminar insertion depth (ALID was defined as the vertical distance between the anterior laminar insertion and a reference plane connecting the Bruch's membrane openings (BMO. The mean LC depth (mLCD was approximated by dividing the area enclosed by the anterior LC, the BMO reference plane, and the two vertical lines for ALID measurement by the length between those two vertical lines. The LC curvature index was defined as the difference between the mLCD and the ALID. The factors influencing the LC curvature index were evaluated.The ALID and mLCD were significantly larger in POAG eyes than in healthy controls (P -6 dB and moderate-to-advanced glaucoma (MD < -6 dB, P = 0.95.LC posterior bowing was increased in POAG eyes, and was significantly associated with structural optic nerve head (ONH changes but not with functional glaucoma severity. Quantitative evaluation of LC curvature can facilitate assessment of glaucomatous ONH change.

  13. Behaviour of Strengthened RC Frames with Eccentric Steel Braced Frames

    Directory of Open Access Journals (Sweden)

    Kamanli Mehmet

    2017-01-01

    Full Text Available After devastating earthquakes in recent years, strengthening of reinforced concrete buildings became an important research topic. Reinforced concrete buildings can be strengthened by steel braced frames. These steel braced frames may be made of concentrically or eccentrically indicated in Turkish Earthquake Code 2007. In this study pushover analysis of the 1/3 scaled 1 reinforced concrete frame and 1/3 scaled 4 strengthened reinforced concrete frames with internal eccentric steel braced frames were conducted by SAP2000 program. According to the results of the analyses conducted, load-displacement curves of the specimens were compared and evaluated. Adding eccentric steel braces to the bare frame decreased the story drift, and significantly increased strength, stiffness and energy dissipation capacity. In this strengthening method lateral load carrying capacity, stiffness and dissipated energy of the structure can be increased.

  14. Mechanical properties of metastable austenitic steels, strengthened by hydroextruction and structural hardening

    International Nuclear Information System (INIS)

    Beresnev, B.I.; Georgieva, I.Ya.; Eshchenko, R.N.; Teplov, V.A.

    1981-01-01

    Different regimes of complex strengthening of steels of Fe-Ni-Mo-C system by phase hardening and plastic deformation by hydroextrusion are investigated. It is stated that the degree of strengthening depends on consequence of strengthening operations. Plastic deformation by hydroextrusion of steels stre--ngthened by phase hardening ensures increase of strength (Δσsub(0.2)=500 MPa) at high plasticity (delta=25%). Maximal values of strength properties can be achieved if hydroextrusion is conducted before and after thansverse α→γ-transformation [ru

  15. Strengthening method of concrete structure

    Science.gov (United States)

    Inge, Wewin; Audrey; Nugroho, Sofie; Njo, Helen

    2018-03-01

    Building extension in Indonesia is not favored, and not many people know the advantages of the method because architects and engineers tend to lack the knowledge and experience. The aim of this paper is to explain a method on how to strengthen a concrete building structure that people can use/learn as a better way to cut potential cost and save time. The strengthening method explained in this paper is steel jacketing, providing a case study of this method in the extension of a restaurant located in Medan, Indonesia. In this study, engineers calculated that the tensile stress of the existing RC column and beam is not strong enough to reinforce the building extension applied load. Therefore, the steel jacketing method can be applied to improve the column and beam strength and ductility. The result of the case study proves that this is one of the best methods for building extension applied in Indonesia.

  16. Strengthening IAEA Safeguards for Research Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Reid, Bruce D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Anzelon, George A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Budlong-Sylvester, Kory [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-01

    broaden the IAEA safeguards toolbox, the study recommends that the Agency consider closing potential gaps in safeguards coverage by, among other things: 1) adapting its safeguards measures based on a case-by-case assessment; 2) using more frequent and expanded/enhanced mailbox declarations (ideally with remote transmission of the data to IAEA Headquarters in Vienna) coupled with short-notice or unannounced inspections; 3) putting more emphasis on the collection and analysis of environmental samples at hot cells and waste storage tanks; 4) taking Safeguards by Design into account for the construction of new research reactors and best practices for existing research reactors; 5) utilizing fully all legal authorities to enhance inspection access (including a strengthened and continuing DIV process); and 6) utilizing new approaches to improve auditing activities, verify reactor operating data history, and track/monitor the movement and storage of spent fuel.

  17. Cellular effects of tributyltin (TBT) on the penis epithelium cells of prosobranchs ( Hinia reticulata and Ocinebrina aciculata)

    Science.gov (United States)

    Brick, M.; Deutsch, U.; Fioroni, P.

    1996-09-01

    Cytopathological effects on organelles of penis epithelium cells were investigated in prosobranchs that had been exposed for two weeks to three months to high TBT-concentrations in artificial seawater. TBT exposure damaged cell organelles, such as mitochondria, Golgi dictyosomes, endoplasmatic reticulum, and injured the cell membranes. In addition, atypical intercellular spaces were observed between the cells of the epithelial layer. Further cell alterations included the increase of residual bodies within the cells as well as structural changes of the basal lamina. The ultrastructural changes were compared with cell alterations of specimens which had been collected in a polluted environment on the coast of Brittany (France).

  18. Fracture mechanical analysis of strengthened concrete tension members with one crack

    DEFF Research Database (Denmark)

    Hansen, Christian Skodborg; Stang, Henrik

    2012-01-01

    A concrete tension member strengthened 2 with fiber reinforced polymer plates on two sides 3 is analyzed with non-linear fracture mechanics. The 4 analysis of the strengthened tension member incorpo5 rates cohesive properties for both concrete and inter6 face between concrete and strengthening...... the structural classification parameters, is inves13 tigated in a non-dimensional analysis, and found to 14 depend strongly on the ratio between interfacial and 15 concrete fracture energies....

  19. Strengthening of tower-like structures. Typical cases of weakening and their repair; Verstaerkung turmartiger Bauwerke. Typische Schwaechungen und ihre Behebung

    Energy Technology Data Exchange (ETDEWEB)

    Noakowski, Piotr; Breddermann, Martin; Harling, Andreas; Rost, Markus; Potratz, Sabine; Leszinski, Holger [FaAA - Failure Analysis Associates Engineering und Forschung im Bauwesen, Duesseldorf (Germany)

    2010-01-15

    In view of our cramped built-up environment, the further use of existing tower-like structures is of high importance. Many of those structures need strengthening which has different causes: sensitive structural design according to old standards and experiences; distinct aging due to severe operation, lack of maintenance and frequent shut down; insufficient wind bearing capacity for upgrading with platforms and antennas; change of the chimney operation to hot or wet flue gases; some flaws in the original structural solutions. The paper describes several strengthening methods for concrete towers, masonry towers, and concrete masts. The projects regard locations of cell phone masts and industrial chimneys which are not specified here. (orig.)

  20. Modeling and characterization of strengthened concrete tension members

    DEFF Research Database (Denmark)

    Hansen, Christian Skodborg; Stang, Henrik

    2011-01-01

    The structural potential for cracking of externally strengthened concrete tension members, can be predicted with three parameters, describing the structural cracking potential based on fracture mechanical properties of the of concrete and interface between concrete and strengthening medium....... With these parameters, it is possible to design reinforcement and obtain a required cracking behavior of a given structure. Design recommendations for single and multiple cracking of the tension specimen are given in terms of fracture mechanical parameters, and a structural stiffness parameter....

  1. Development of the strengthened safeguards system and the Additional Protocol

    International Nuclear Information System (INIS)

    Vidaurre-Henry, Jaime

    2001-01-01

    For the past 30 years, the IAEA's safeguards system has contributed to the international non-proliferation regime by providing, inter alia, assurances regarding the peaceful uses of declared nuclear material. However, the discovery of a clandestine nuclear weapons program in Iraq in 1991 drew world-wide attention to the need to strengthen the system to address the absence of undeclared nuclear material and activities. Efforts to strengthen the IAEA's safeguards system began in 1991 and culminated in 1997 when the IAEA's Board of Governors approved a Model Protocol Additional to IAEA Safeguards Agreements which greatly expands the legal basis and scope of IAEA safeguards. Within this strengthened system it is expected that the IAEA be able to provide assurance not only of the absence of diversion of declared nuclear material but also on the absence of undeclared nuclear material and activities. This is to be done within a safeguards system that uses an optimal combination of all safeguards measures available, thereby achieving maximum effectiveness and efficiency within the available resources. The paper summarizes the evolution of the safeguards system, describes strengthened safeguards, reports on the status of implementing the strengthening measures, and outlines plans for integrating all available safeguards measures. (author)

  2. Flexure Behavior of Hybrid Continuous Deep Beam Strengthened by Carbon Fiber Reinforced Polymer

    Directory of Open Access Journals (Sweden)

    Hayder M.K.Al-Mutairee

    2017-08-01

    Full Text Available This study present an experimental investigation for overall flexure behavior of reinforced concrete continuous deep beams (RCCDB made of hybrid concrete, normal strength concrete (NSC and high strength concrete (HSC at different location and percentage. The experimental work includes testing of sixteen specimens of RCCDB under two points loads. The effects of HSC layer thickness and CFRP on strength of RCCDB had been studied. The experimental results showed that the strengthening of RCCDB by HSC layer from top is better than from bottom, where the increment in the ultimate flexural strength increased by (14,21,27% for top strengthening and (12,15,13% for bottom strengthening for (25,50,75% thickness of total depth of beam respectively. The optimal strengthening of RCCDB by HSC layer at top was of 25%. The results also proved that the strengthening of hybrid RCCDB by (10,15cm CFRP strip at the bottom for flexure gave increment in the ultimate strength by (32, 29% respectively, and the strengthening by CFRP strip for flexure at the bottom is better than at top for hybrid RCCDB. The shear strengthening of hybrid RCCDB increases the ultimate strength by 23.4% and 13.8% if the strengthening has O and U shape respectively

  3. Dispersion strengthening

    International Nuclear Information System (INIS)

    Scattergood, R.O.; Das, E.S.P.

    1976-01-01

    Using digital computer-based methods, models for dispersion strengthening can now be developed which take into account many of the important effects that have been neglected in the past. In particular, the self interaction of a dislocation can be treated, and a computer simulation method was developed to determine the flow stress of a random distribution of circular, impenetrable obstacles, taking into account all such interactions. The flow stress values depended on the obstacle sizes and spacings, over and above the usual 1/L dependence where L is the average obstacle spacing. From an analysis of the results, it was found that the main effects of the self interactions can be captured in a line tension analogue in which the obstacles appear to be penetrable

  4. Effect of the wave shocking treatment on the structure and strengthening of austenitic steels

    International Nuclear Information System (INIS)

    Blinov, V.M.; Chernogorova, O.P.; Drozdova, E.I.; Afanas'ev, I.A.

    2006-01-01

    The structure and hardening of austenitic manganese steels after shock wave treatment are studied. It is shown that the treatment results in the structure where an elementary cell size decreases with a pressure increase. The strain hardening resulted from shock wave loading can be estimated using a Hall-Petch equation. It is established that at similar degree of residual strains the shock wave loading compared to cold rolling gives rise to higher strengthening which value grows as austenite stacking fault energy decreases [ru

  5. Ab initio identified design principles of solid-solution strengthening in Al

    International Nuclear Information System (INIS)

    Ma Duancheng; Friák, Martin; Pezold, Johann von; Raabe, Dierk; Neugebauer, Jörg

    2013-01-01

    Solid-solution strengthening in six Al–X binary systems is investigated using first-principle methods. The volumetric mismatch parameter and the solubility enthalpy per solute were calculated. We derive three rules for designing solid-solution strengthened alloys: (i) the solubility enthalpy per solute is related to the volumetric mismatch by a power law; (ii) for each annealing temperature, there exists an optimal solute–volume mismatch to achieve maximum strength; and (iii) the strengthening potential of high volumetric mismatch solutes is severely limited by their low solubility. Our results thus show that the thermodynamic properties of the system (here Al–X alloys) set clear upper bounds to the achievable strengthening effects owing to the reduced solubility with increasing volume mismatch. (paper)

  6. Strengthening the non proliferation regime: French views

    International Nuclear Information System (INIS)

    Delaune, P.

    2013-01-01

    3 main issues can be identified in the French policy concerning the backing of non proliferation: 1) responding resolutely to proliferation crises, 2) reinforcing substantive efforts to prevent and impede proliferation, and 3) strengthening the non-proliferation regime. The first issue is very important because combating proliferation is vital to the security of all. Concerning the second issue, France attaches particular importance to strengthening specific measures to prevent and check proliferation. Let me mention a few proposals that we put forward: exports need to be controlled more effectively, proliferation activities have to be criminalized, or the development of proliferation-resistant technologies should be supported. Concerning the third issue it means the strengthening of the non-proliferation regime, France proposes several means: -) aiming at the universalization of the additional protocol; -) ensuring that the Agency continues to have sufficient human, financial and technical resources to fulfill its verification mission effectively; -) encouraging the IAEA to make full use of the authority available to it; -) enhancing the use of information relevant to the delivery of the IAEA mandate; and -) sharing more accurate information concerning the breaches of commitments that happen. The paper is followed by the slides of the presentation. (A.C.)

  7. The influence of resin flexural modulus on the magnitude of ceramic strengthening.

    LENUS (Irish Health Repository)

    Fleming, Garry J P

    2012-07-01

    The aim was to determine the magnitude of ceramic resin-strengthening with resin-based materials with varying flexural moduli using a regression technique to assess the theoretical strengthening at a \\'zero\\' resin-coating thickness. The hypothesis tested was that experimentally, increasing resin flexural modulus results in increased resin-strengthening observed at a theoretical \\'zero\\' resin-coating thickness.

  8. Characterization of strengthening mechanism and hot deformation behavior of powder metallurgy molybdenum

    International Nuclear Information System (INIS)

    Xiao, Meili; Li, Fuguo; Xie, Hangfang; Wang, Yufeng

    2012-01-01

    Highlights: → Dynamic recrystallization of powder metallurgy molybdenum occurs in the temperature region (1200-1450 o C). → The value of strain hardening index n decreases along with the temperature rising. → The value of strain-rate sensitivity exponent m increases slowly at first and achieves a peak value at 1350 o C. → Deformation strengthening is the main strengthening mechanism at low temperature. → Rheological strengthening becomes the primary strengthening mechanism at high temperature. -- Abstract: The high-temperature deformation behavior of powder metallurgy molybdenum has been investigated based on a series of isothermal hot compression tests, which were carried out on a Gleeble-1500 thermal mechanical simulator in a wide range of temperatures (900-1450 o C) and strain rates (0.01-10 s -1 ). Through the research on the experimental stress-strain curves, it reveals that dynamic recrystallization softening effect of powder metallurgy molybdenum occurs in the temperature range from 1200 o C to 1450 o C, in which the flow stress is significantly sensitive to temperature. In comparison with the value of strain hardening index n which decreases along with the temperature rising, the value of strain-rate sensitivity exponent m does not change obviously; however, it increases slowly with the increasing of temperature at first and achieves a peak value at 1350 o C. Furthermore, relying on the comparison of mean value of n and m, it is suggested that deformation strengthening is the main strengthening mechanism at low temperature while the rheological strengthening changes into the primary strengthening mechanism at high temperature.

  9. Strengthening Performance of PALF-Epoxy Composite Plate on Reinforced Concrete Beams

    Science.gov (United States)

    Chin, Siew C.; Tong, Foo S.; Doh, Shu I.; Gimbun, Jolius; Ong, Huey R.; Serigar, Januar P.

    2018-03-01

    This paper presents the effective strengthening potential of pineapple leaves fiber (PALF)-epoxy composite plate on reinforced concrete (RC) beam. At first the PALF is treated with alkali (NaOH) and its morphology is observed via scanning electron microscope (SEM). The composite plates made of PALF and epoxy with fiber loading ranging from 0.1 to 0.4 v/v was tested for its flexural behaviour. The composite was then used for external RC beam strengthening. The structural properties of RC beams were evaluated and all the beams were tested under four-point bending. It was found that the flexural strength increased as the fiber volume ratio increases. The maximum flexural strength (301.94 MPa) was obtained at the fiber volume ratio of 40%. The beam strengthened with PALF-epoxy composite plate has a 7% higher beam capacity compared to the control beam. Cracks formed at the edge of the plate of PALF-strengthened beams resulted in diagonal cracking. Result from this work shows that the PALF-epoxy composite plate has the potential to be used as external strengthening material for RC beam.

  10. A Review on Strengthening Steel Beams Using FRP under Fatigue

    Directory of Open Access Journals (Sweden)

    Mohamed Kamruzzaman

    2014-01-01

    Full Text Available In recent decades, the application of fibre-reinforced polymer (FRP composites for strengthening structural elements has become an efficient option to meet the increased cyclic loads or repair due to corrosion or fatigue cracking. Hence, the objective of this study is to explore the existing FRP reinforcing techniques to care for fatigue damaged structural steel elements. This study covers the surface treatment techniques, adhesive curing, and support conditions under cyclic loading including fatigue performance, crack propagation, and failure modes with finite element (FE simulation of the steel bridge girders and structural elements. FRP strengthening composites delay initial cracking, reduce the crack growth rate, extend the fatigue life, and decrease the stiffness decay with residual deflection. Prestressed carbon fibre-reinforced polymer (CFRP is the best strengthening option. End anchorage prevents debonding of the CRRP strips at the beam ends by reducing the local interfacial shear and peel stresses. Hybrid-joint, nanoadhesive, and carbon-flex can also be attractive for strengthening systems.

  11. A review on strengthening steel beams using FRP under fatigue.

    Science.gov (United States)

    Kamruzzaman, Mohamed; Jumaat, Mohd Zamin; Sulong, N H Ramli; Islam, A B M Saiful

    2014-01-01

    In recent decades, the application of fibre-reinforced polymer (FRP) composites for strengthening structural elements has become an efficient option to meet the increased cyclic loads or repair due to corrosion or fatigue cracking. Hence, the objective of this study is to explore the existing FRP reinforcing techniques to care for fatigue damaged structural steel elements. This study covers the surface treatment techniques, adhesive curing, and support conditions under cyclic loading including fatigue performance, crack propagation, and failure modes with finite element (FE) simulation of the steel bridge girders and structural elements. FRP strengthening composites delay initial cracking, reduce the crack growth rate, extend the fatigue life, and decrease the stiffness decay with residual deflection. Prestressed carbon fibre-reinforced polymer (CFRP) is the best strengthening option. End anchorage prevents debonding of the CRRP strips at the beam ends by reducing the local interfacial shear and peel stresses. Hybrid-joint, nanoadhesive, and carbon-flex can also be attractive for strengthening systems.

  12. A Review on Strengthening Steel Beams Using FRP under Fatigue

    Science.gov (United States)

    Jumaat, Mohd Zamin; Ramli Sulong, N. H.

    2014-01-01

    In recent decades, the application of fibre-reinforced polymer (FRP) composites for strengthening structural elements has become an efficient option to meet the increased cyclic loads or repair due to corrosion or fatigue cracking. Hence, the objective of this study is to explore the existing FRP reinforcing techniques to care for fatigue damaged structural steel elements. This study covers the surface treatment techniques, adhesive curing, and support conditions under cyclic loading including fatigue performance, crack propagation, and failure modes with finite element (FE) simulation of the steel bridge girders and structural elements. FRP strengthening composites delay initial cracking, reduce the crack growth rate, extend the fatigue life, and decrease the stiffness decay with residual deflection. Prestressed carbon fibre-reinforced polymer (CFRP) is the best strengthening option. End anchorage prevents debonding of the CRRP strips at the beam ends by reducing the local interfacial shear and peel stresses. Hybrid-joint, nanoadhesive, and carbon-flex can also be attractive for strengthening systems. PMID:25243221

  13. [Dermoepidermic junction: a selective, complex and vital barrier].

    Science.gov (United States)

    Frede, Silvia C; Dionisio de Cabalier, María E; Zaya, Alejandro; Hliba, Ernesto

    2004-01-01

    Dermoepidermic junction (DEJ) is a highly complex region, containing a great variety of cellular elements, which despite of having different embriogenesis, interact with each other, generating different substances that keep the function and homeostasis of the greatest organ of the human body. DEJ is regarded as a highly specialized basal lamina, which acts as a highly selective pathway for the migration of cells and macromolecules, inducing cellular differentiation and micro enviromental metabolism modifications. DEJ may be divided into three zones regarding the basal lamina 1--the nearest to epidermic zone, having tonofilaments and hemidesmosomes, which keep anchored basal cells. This region is limited by the lamina densa 2--the intermediate zone, represented exclusively by lamina densa and finally the lamina 3,--the third region--extends from lamina densa to the upper dermis and extracelullar matrix. Despite there is much to learn about DEJ, the knowledge about each molecule and function of every compartment will enable us to know more about the pathogenesis of several dermatologic diseases, with a great prevalence in the clinical practice.

  14. Epidemiological investigation of muscle-strengthening activities and cognitive function among older adults.

    Science.gov (United States)

    Loprinzi, Paul D

    2016-06-01

    Limited research has examined the association of muscle-strengthening activities and executive cognitive function among older adults, which was this study's purpose. Data from the 1999-2002 NHANES were employed (N = 2157; 60-85 years). Muscle-strengthening activities were assessed via self-report, with cognitive function assessed using the digit symbol substitution test. After adjusting for age, age-squared, gender, race-ethnicity, poverty level, body mass index, C-reactive protein, smoking, comorbid illness and physical activity, muscle-strengthening activities were significantly associated with cognitive function (βadjusted = 3.4; 95% CI: 1.7-5.1; P cognitive function score. In conclusion, muscle-strengthening activities are associated with executive cognitive function among older U.S. adults, underscoring the importance of promoting both aerobic exercise and muscle-strengthening activities to older adults. © The Author(s) 2016.

  15. Cardiovascular fitness strengthening using portable device.

    Science.gov (United States)

    Alqudah, Hamzah; Kai Cao; Tao Zhang; Haddad, Azzam; Su, Steven; Celler, Branko; Nguyen, Hung T

    2016-08-01

    The paper describes a reliable and valid Portable Exercise Monitoring system developed using TI eZ430-Chronos watch, which can control the exercise intensity through audio stimulation in order to increase the Cardiovascular fitness strengthening.

  16. Estimated Trans-Lamina Cribrosa Pressure Differences in Low-Teen and High-Teen Intraocular Pressure Normal Tension Glaucoma: The Korean National Health and Nutrition Examination Survey

    OpenAIRE

    Lee, Si Hyung; Kwak, Seung Woo; Kang, Eun Min; Kim, Gyu Ah; Lee, Sang Yeop; Bae, Hyoung Won; Seong, Gong Je; Kim, Chan Yun

    2016-01-01

    Background To investigate the association between estimated trans-lamina cribrosa pressure difference (TLCPD) and prevalence of normal tension glaucoma (NTG) with low-teen and high-teen intraocular pressure (IOP) using a population-based study design. Methods A total of 12,743 adults (? 40 years of age) who participated in the Korean National Health and Nutrition Examination Survey (KNHANES) from 2009 to 2012 were included. Using a previously developed formula, cerebrospinal fluid pressure (C...

  17. Strengthening of structurally damaged wide shallow RC beams using externally bonded CFRP plates

    Directory of Open Access Journals (Sweden)

    Rajeh A. Al-Zaid

    Full Text Available Reinforced concrete wide shallow beams (WSBs are commonly used in the joist flooring systems. The structural behavior of WSBs strengthened with carbon fiber reinforced polymer (CFRP reinforcement was studied on isolated beams and as part of full-scale building. The effect of structural damage on the performance of WSBs flexurally strengthened with CFRP plates was investigated and presented in this paper. Eight full-scale WSBs were tested under four-point bending up to failure. Seven beams were strengthened with CFRP plates bonded to the soffit of the beams and one beam was unstrengthened serving as control. Prior to strengthening, the beams were subjected to different levels of damaging by preloading to 30-95% of the beams' flexural capacity. One beam was fully damaged by preloading to failure and repaired before strengthening by replacing the crushed concrete. The data showed that the pre-damaged strengthened beams exhibited ultimate capacities up to 8% lower than those of the undamaged strengthened beams. However, the load carrying capacities of pre-damaged strengthened beams were more than those predicted by ACI 440 design guide, fib Bulletin 14, and JSCE design recommendations. Both fib Bulletin 14 and JSCE design recommendations gave very conservative predictions with average ratios of experimental to predicted ultimate capacity of 2.02 and 2.35, respectively. More accurate predictions were obtained by ACI 440 design guide as the corresponding ratio was 1.24. These results indicate that strong confidence and reliability can be placed in applying CFRP strengthening to structurally damaged WSBs.

  18. 77 FR 38017 - Regulation Strengthening Accountability of Attorneys and Non-Attorney Representatives Appearing...

    Science.gov (United States)

    2012-06-26

    ...-2168-01] RIN 0625-AA92 Regulation Strengthening Accountability of Attorneys and Non- Attorney... strengthens the accountability of attorneys and non-attorney representatives who appear in proceedings before... administration of the U.S. AD and CVD laws. One proposal addressed strengthening the accountability of attorneys...

  19. A new 12% chromium steel strengthened by Z-phase precipitates

    DEFF Research Database (Denmark)

    Liu, Fang; Rashidi, Masoud; Johansson, Lennart

    2016-01-01

    In order to increase the corrosion resistance and simultaneously maintain the creep resistance of 9-12% Cr steels at 650 degrees C, a new alloy design concept was proposed, using thermodynamically stable Z-phase (CrTaN) precipitates to strengthen the steel. A new trial Z-phase strengthened 12% Cr...

  20. Effect of CFRP and TRM Strengthening of RC Slabs on Punching Shear Strength

    Directory of Open Access Journals (Sweden)

    Husain Abbas

    Full Text Available Abstract The paper presents experiments involving punching of RC slabs strengthened using externally bonded carbon fiber reinforced polymer (CFRP sheet and textile reinforced mortar (TRM. Twelve RC slab specimens of two concrete grades (39.9 and 63.2 MPa and employing two strengthening schemes (CFRP and TRM were tested. Specimens were supported on two opposite edges. Experimental load-displacement variations show two peak loads in strengthened slabs and one peak followed by a plateau in control. Second peak or the plateau corresponds to the combined action of aggregate interlock and the dowel action of back face rebars and strengthening layers. The dowel action of back face rebars and strengthening layers had no role in ultimate punching load (i.e. first peak. Strengthened slabs showed 9-18% increase in ultimate punching load (i.e. first peak whereas there was significant increase in the second peak load (190-276% for CFRP; 55-136% for TRM and energy absorption (~66% for CFRP and 22-56% for TRM. An analytical model was also developed for predicting the punching shear strength (first and second peaks of strengthened slabs showing good comparison with experiments.

  1. CD4+ T lymphocytes injected into severe combined immunodeficient (SCID) mice lead to an inflammatory and lethal bowel disease

    DEFF Research Database (Denmark)

    Claesson, Mogens Helweg; Rudolphi, A; Kofoed, S

    1996-01-01

    Transfer of 2 x 10(5) congenic or semiallogenic purified TCR alphabeta+ CD4+ T cells to SCID mice leads to an infiltration of the recipient gut lamina propria and epithelium with a donor-derived CD4+ T cell subset which induces a lethal inflammatory bowel disease (IBD) in the recipients....... In contrast, IBD was not observed in SCID mice transplanted with unfractionated splenic cells. The earliest detectable pathological changes after CD4+ T cell transfer were proliferation and hypertrophy of the entire colonic epithelial layer, including increased mitotic activity, increased expression...... plasma cells were present in the lamina propria of both the small and large intestine. We conclude that low numbers of intraveneously transferred CD4+ T cells induce IBD in SCID mice. In the late stages of CD4+ T cell-induced IBD, the colonic lamina propria becomes infiltrated with macrophages...

  2. Association of Lung Inflammatory Cells with Small Airways Function and Exhaled Breath Markers in Smokers - Is There a Specific Role for Mast Cells?

    Directory of Open Access Journals (Sweden)

    Yvonne Nussbaumer-Ochsner

    Full Text Available Smoking is associated with a mixed inflammatory infiltrate in the airways. We evaluated whether airway inflammation in smokers is related to lung function parameters and inflammatory markers in exhaled breath.Thirty-seven smokers undergoing lung resection for primary lung cancer were assessed pre-operatively by lung function testing including single-breath-nitrogen washout test (sb-N2-test, measurement of fractional exhaled nitric oxide (FeNO and pH/8-isoprostane in exhaled breath condensate (EBC. Lung tissue sections containing cancer-free large (LA and small airways (SA were stained for inflammatory cells. Mucosal (MCT respectively connective tissue mast cells (MCTC and interleukin-17A (IL-17A expression by mast cells was analysed using a double-staining protocol.The median number of neutrophils, macrophages and mast cells infiltrating the lamina propria and adventitia of SA was higher than in LA. Both MCTC and MCT were higher in the lamina propria of SA compared to LA (MCTC: 49 vs. 27.4 cells/mm2; MCT: 162.5 vs. 35.4 cells/mm2; P<0.005 for both instances. IL-17A expression was predominantly detected in MCTC of LA. Significant correlations were found for the slope of phase III % pred. of the sb-N2-test (rs= -0.39, for the FEV1% pred. (rs= 0.37 and for FEV1/FVC ratio (rs=0.38 with MCT in SA (P<0.05 for all instances. 8-isoprostane concentration correlated with the mast cells in the SA (rs=0.44, there was no correlation for pH or FeNO with cellular distribution in SA.Neutrophils, macrophages and mast cells are more prominent in the SA indicating that these cells are involved in the development of small airway dysfunction in smokers. Among these cell types, the best correlation was found for mast cells with lung function parameters and inflammatory markers in exhaled breath. Furthermore, the observed predominant expression of IL-17A in mast cells warrants further investigation to elucidate their role in smoking-induced lung injury, despite the

  3. Using Evidence to Strengthen Health Systems in Africa and the ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    The project is timely for Lebanon, a country that is working to strengthen its primary health care system to respond to current priorities such as the emerging crisis of Syrian refugees. Timely access to information The project will strengthen institutional and individual abilities to conduct and use systematic and rapid reviews to ...

  4. Epithelial Label-Retaining Cells Are Absent during Tooth Cycling in Salmo salar and Polypterus senegalus.

    Directory of Open Access Journals (Sweden)

    Sam Vandenplas

    Full Text Available The Atlantic salmon (Salmo salar and African bichir (Polypterus senegalus are both actinopterygian fish species that continuously replace their teeth without the involvement of a successional dental lamina. Instead, they share the presence of a middle dental epithelium: an epithelial tier enclosed by inner and outer dental epithelium. It has been hypothesized that this tier could functionally substitute for a successional dental lamina and might be a potential niche to house epithelial stem cells involved in tooth cycling. Therefore, in this study we performed a BrdU pulse chase experiment on both species to (1 determine the localization and extent of proliferating cells in the dental epithelial layers, (2 describe cell dynamics and (3 investigate if label-retaining cells are present, suggestive for the putative presence of stem cells. Cells proliferate in the middle dental epithelium, outer dental epithelium and cervical loop at the lingual side of the dental organ to form a new tooth germ. Using long chase times, both in S. salar (eight weeks and P. senegalus (eight weeks and twelve weeks, we could not reveal the presence of label-retaining cells in the dental organ. Immunostaining of P. senegalus dental organs for the transcription factor Sox2, often used as a stem cell marker, labelled cells in the zone of outer dental epithelium which grades into the oral epithelium (ODE transition zone and the inner dental epithelium of a successor only. The location of Sox2 distribution does not provide evidence for epithelial stem cells in the dental organ and, more specifically, in the middle dental epithelium. Comparison of S. salar and P. senegalus reveals shared traits in tooth cycling and thus advances our understanding of the developmental mechanism that ensures lifelong replacement.

  5. NLRP3 Controls the Development of Gastrointestinal CD11b+ Dendritic Cells in the Steady State and during Chronic Bacterial Infection

    Directory of Open Access Journals (Sweden)

    Isabelle C. Arnold

    2017-12-01

    Full Text Available The gastric lamina propria is largely uncharted immunological territory. Here we describe the evolution and composition of the gastric, small intestinal, and colonic lamina propria mononuclear phagocyte system during the steady state and infection with the gastric pathogen Helicobacter pylori. We show that monocytes, CX3CR1hi macrophages, and CD11b+ dendritic cells are recruited to the infected stomach in a CCR2-dependent manner. All three populations, but not BATF3-dependent CD103+ DCs, sample red fluorescent protein (RFP+ Helicobacter pylori (H. pylori. Mice reconstituted with human hematopoietic stem cells recapitulate several features of the myeloid cell-H. pylori interaction. The differentiation in and/or recruitment to gastrointestinal, lung, and lymphoid tissues of CD11b+ DCs requires NLRP3, but not apoptosis-associated speck-like protein containing a carboxy-terminal CARD (ASC or caspase-1, during steady-state and chronic infection. NLRP3−/− mice fail to generate Treg responses to H. pylori and control the infection more effectively than wild-type mice. The results demonstrate a non-canonical inflammasome-independent function of NLRP3 in DC development and immune regulation.

  6. Strengthening a consolidated memory: the key role of the reconsolidation process.

    Science.gov (United States)

    Forcato, Cecilia; Fernandez, Rodrigo S; Pedreira, María E

    2014-01-01

    The reconsolidation hypothesis posits that the presentation of a specific cue, previously associated with a life event, makes the stored memory pass from a stable to a reactivated state. In this state, memory is again labile and susceptible to different agents, which may either damage or improve the original memory. Such susceptibility decreases over time and leads to a re-stabilization phase known as reconsolidation process. This process has been assigned two biological roles: memory updating, which suggests that destabilization of the original memory allows the integration of new information into the background of the original memory; and memory strengthening, which postulates that the labilization-reconsolidation process strengthens the original memory. The aim of this review is to analyze the strengthening as an improvement obtained only by triggering such process without any other treatment. In our lab, we have demonstrated that when triggering the labilization-reconsolidation process at least once the original memory becomes strengthened and increases its persistence. We have also shown that repeated labilization-reconsolidation processes strengthened the original memory by enlarging its precision, and said reinforced memories were more resistant to interference. Finally, we have shown that the strengthening function is not operative in older memories. We present and discuss both our findings and those of others, trying to reveal the central role of reconsolidation in the modification of stored information. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Strengthening of Steel Columns under Load: Torsional-Flexural Buckling

    Directory of Open Access Journals (Sweden)

    Martin Vild

    2016-01-01

    Full Text Available The paper presents experimental and numerical research into the strengthening of steel columns under load using welded plates. So far, the experimental research in this field has been limited mostly to flexural buckling of columns and the preload had low effect on the column load resistance. This paper focuses on the local buckling and torsional-flexural buckling of columns. Three sets of three columns each were tested. Two sets corresponding to the base section (D and strengthened section (E were tested without preloading and were used for comparison. Columns from set (F were first preloaded to the load corresponding to the half of the load resistance of the base section (D. Then the columns were strengthened and after they cooled, they were loaded to failure. The columns strengthened under load (F had similar average resistance as the columns welded without preloading (E, meaning the preload affects even members susceptible to local buckling and torsional-flexural buckling only slightly. This is the same behaviour as of the tested columns from previous research into flexural buckling. The study includes results gained from finite element models of the problem created in ANSYS software. The results obtained from the experiments and numerical simulations were compared.

  8. Carbon fiber-reinforced polymer strengthening and monitoring of the grondals bridge in Sweden

    DEFF Research Database (Denmark)

    Täljsten, Björn; Hejll, Arvid; James, Gerard

    2007-01-01

    to be strengthened. The strengthening methods used were CFRP plates at the serviceability limit state and prestressed dywidag stays at the ultimate limit state. The strengthening was carried out during 2002. At the same time monitoring of the bridge commenced, using LVDT crack gauges as well as optical fiber sensors....

  9. Theoretical multi-physics approaches to solid-solution strengthening of Al

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Duancheng; Friak, Martin; Raabe, Dierk; Neugebauer, Joerg [Max-Planck-Institut fuer Eisenforschung GmbH, Duesseldorf (Germany)

    2009-07-01

    The strengthening of soft metallic materials has a long tradition and is an important metallurgical topic since the time when ancient smiths forged the first swords. Intense materials research revealed a combination of three mechanisms as decisive for solid-solution strengthening phenomena: (i) the size mismatch of components (Mott and Nabarro's parelastic concept), (ii) the elastic modulus mismatch of atoms (Fleischer's dielastic contribution), and (iii) the concentration of solutes (statistical concept of Friedel and Labusch). Combining density functional theory calculations and linear-elasticity theory, the key parameters that are essential for the classical strengthening theories are determined in order to test them and identify their possible validity limits. The strengthening of fcc aluminium is chosen as an example and a series of binary systems Al-X (with X=Ca,Sr,Ir,Li,Mg,Cu) was considered. Comparing our results with those obtained by applying classical theories we find clear deviations. These deviations originate from non-classical lattice distortions due to the size mismatch of solute atoms in their first coordination shells.

  10. FRP Composites Strengthening of Concrete Columns under Various Loading Conditions

    Directory of Open Access Journals (Sweden)

    Azadeh Parvin

    2014-04-01

    Full Text Available This paper provides a review of some of the progress in the area of fiber reinforced polymers (FRP-strengthening of columns for several loading scenarios including impact load. The addition of FRP materials to upgrade deficiencies or to strengthen structural components can save lives by preventing collapse, reduce the damage to infrastructure, and the need for their costly replacement. The retrofit with FRP materials with desirable properties provides an excellent replacement for traditional materials, such as steel jacket, to strengthen the reinforced concrete structural members. Existing studies have shown that the use of FRP materials restore or improve the column original design strength for possible axial, shear, or flexure and in some cases allow the structure to carry more load than it was designed for. The paper further concludes that there is a need for additional research for the columns under impact loading senarios. The compiled information prepares the ground work for further evaluation of FRP-strengthening of columns that are deficient in design or are in serious need for repair due to additional load or deterioration.

  11. Perlecan controls neurogenesis in the developing telencephalon

    Directory of Open Access Journals (Sweden)

    Fairén Alfonso

    2007-04-01

    Full Text Available Abstract Background Perlecan is a proteoglycan expressed in the basal lamina of the neuroepithelium during development. Perlecan absence does not impair basal lamina assembly, although in the 55% of the mutants early disruptions of this lamina conducts to exencephaly, impairing brain development. The rest of perlecan-null brains complete its prenatal development, maintain basal lamina continuity interrupted by some isolated ectopias, and are microcephalic. Microcephaly consists of thinner cerebral walls and underdeveloped ganglionic eminences. We have studied the mechanisms that generate brain atrophy in telencephalic areas where basal lamina is intact. Results Brain atrophy in the absence of perlecan started in the ventral forebrain and extended to lateral and dorsal parts of the cortex in the following stages. First, the subpallial forebrain developed poorly in early perlecan-null embryos, because of a reduced cell proliferation: the number of cells in mitosis decreased since the early stages of development. This reduction resulted in a decreased tangential migration of interneurons to the cerebral cortex. Concomitant with the early hypoplasia observed in the medial ganglionic eminences, Sonic Hedgehog signal decreased in the perlecan-null floor plate basal lamina at E12.5. Second, neurogenesis in the pallial neuroepithelium was affected in perlecan deficient embryos. We found reductions of nearly 50% in the number of cells exiting the cell cycle at E12–E13. The labeling index, which was normal at this age, significantly decreased with advancing corticogenesis. Moreover, nestin+ or PCNA+ progenitors increased since E14.5, reaching up to about 150% of the proportion of PCNA+ cells in the wild-type at E17.5. Thus, labeling index reduction together with increased progenitor population, suggests that atrophy is the result of altered cell cycle progression in the cortical progenitors. Accordingly, less neurons populated the cortical plate and

  12. Seismic evaluation and strengthening of Bohunice nuclear power plant structures

    International Nuclear Information System (INIS)

    Shipp, J.G.; Short, S.A.; Grief, T.; Borov, V.; Kuzma, J.

    2001-01-01

    A seismic assessment and strengthening investigation is being performed for selected structures at the Bohunice V1 Nuclear Power Plant in Slovakia. Structures covered in this paper include the reactor building complex and the emergency generator station. The emergency generator station is emphasized in the paper as work is nearly complete while work on the reactor building complex is ongoing at this time. Seismic evaluation and strengthening work is being performed by a cooperative effort of Siemens and EQE along with local contractors. Seismic input is the interim Review Level Earthquake (horizontal peak ground acceleration of 0.3 g). The Bohunice V1 reactor building complex is a WWER 4401230 nuclear power plant that was originally built in the mid-1970s but had extensive seismic upgrades in 1991. Siemens has performed three dimensional dynamic analyses of the reactor building complex to develop seismic demand in structural elements. EQE is assessing seismic capacities of structural elements and developing strengthening schemes, where needed. Based on recent seismic response analyses for the interim Review Level Earthquake which account for soil-structure interaction in a rigorous manner, the 1991 seismic upgrade has been found to be inadequate in both member/connection strength and in providing complete load paths to the foundation. Additional strengthening is being developed. The emergency generator station was built in the 1970s and is a two-story unreinforced brick masonry (URM) shear wall building above grade with a one story reinforced concrete shear wall basement below grade. Seismic analyses and testing of the URM walls has been performed to assess the need for building strengthening. Required structural strengthening for in-plane forces consists of revised and additional vertical steel framing and connections, stiffening of horizontal roof bracing, and steel connections between the roof and supporting walls and pointing of two interior transverse URM

  13. Cogels of Hyaluronic Acid and Acellular Matrix for Cultivation of Adipose-Derived Stem Cells: Potential Application for Vocal Fold Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Dongyan Huang

    2016-01-01

    Full Text Available Stem cells based tissue engineering has been one of the potential promising therapies in the research on the repair of tissue diseases including the vocal fold. Decellularized extracellular matrix (DCM as a promising scaffold has be used widely in tissue engineering; however, it remained to be an important issue in vocal fold regeneration. Here, we applied the hydrogels (hyaluronic acid [HA], HA-collagen [HA-Col], and HA-DCM to determine the effects of hydrogel on the growth and differentiation of human adipose-derived stem cells (hADSCs into superficial lamina propria fibroblasts. hADSCs were isolated and characterized by fluorescence-activated cell sorting. The results indicated that HA-DCM hydrogel enhanced cell proliferation and prolonged cell morphology significantly compared to HA and HA-Col hydrogel. Importantly, the differentiation of hADSCs into fibroblasts was also promoted by cogels of HA-Col and HA-DCM significantly. The differentiation of hADSCs towards superficial lamina propria fibroblasts was accelerated by the secretion of HGF, IL-8, and VEGF, the decorin and elastin expression, and the synthesis of chondroitin sulfate significantly. Therefore, the cogel of HA-DCM hydrogel was shown to be outstanding in apparent stimulation of hADSCs proliferation and differentiation to vocal fold fibroblasts through secretion of important growth factors and synthesis of extracellular matrix.

  14. Strengthening health system to improve immunization for migrants in China.

    Science.gov (United States)

    Fang, Hai; Yang, Li; Zhang, Huyang; Li, Chenyang; Wen, Liankui; Sun, Li; Hanson, Kara; Meng, Qingyue

    2017-07-01

    Immunization is the most cost-effective method to prevent and control vaccine-preventable diseases. Migrant population in China has been rising rapidly, and their immunization status is poor. China has tried various strategies to strengthen its health system, which has significantly improved immunization for migrants. This study applied a qualitative retrospective review method aiming to collect, analyze and synthesize health system strengthening experiences and practices about improving immunizations for migrants in China. A conceptual framework of Theory of Change was used to extract the searched literatures. 11 searched literatures and 4 national laws and policies related to immunizations for migrant children were carefully studied. China mainly employed 3 health system strengthening strategies to significantly improve immunization for migrant population: stop charging immunization fees or immunization insurance, manage immunization certificates well, and pay extra attentions on immunization for special children including migrant children. These health system strengthening strategies were very effective, and searched literatures show that up-to-date and age-appropriate immunization rates were significantly improved for migrant children. Economic development led to higher migrant population in China, but immunization for migrants, particularly migrant children, were poor. Fortunately various health system strengthening strategies were employed to improve immunization for migrants in China and they were rather successful. The experiences and lessons of immunization for migrant population in China might be helpful for other developing countries with a large number of migrant population.

  15. Escapist Motives for On-line Gaming and Strengthening of Weak Ties

    DEFF Research Database (Denmark)

    Sudzina, Frantisek; Razmerita, Liana

    on-line gaming. The research investigates Facebook and other on-line games separate-ly. A surprising result is that while most of the investigated escapist motives are positively correlated with strengthening of weak ties, the mundane breaking motive is negatively correlated with strengthening...

  16. The Strengthening Nuclear Security Implementation initiative: evolution, status and next steps

    NARCIS (Netherlands)

    Dal, B.; Herbach, J.; Luongo, K.N.

    2015-01-01

    The "Strengthening Nuclear Security Implementation" initiative broke new ground at the 2014 Nuclear Security Summit in the effort to harmonize and strengthen the global nuclear security regime. This report discusses the significance of the initiative, the importance of expanding its signatories, and

  17. Identification of Interstitial Cajal-like cells in the Human Thoracic Duct

    DEFF Research Database (Denmark)

    Bødtkjer, Donna Marie Briggs; Rumessen, Jüri; Baandrup, Ulrik

    2013-01-01

    were used to identify ICLCs in live tissue. Methylene blue stained cells with morphology suggestive of ICLCs in the TD. Immunoreactivity localized the ICLC protein markers c-kit, CD34 and vimentin to many cells and processes associated with smooth muscle cells (SMCs): coexpression of c......-kit with vimentin or CD34 was observed in some cells. Electron microscopy analysis confirmed ICLCs as a major cell type of the human TD. Lymphatic ICLCs possess caveolae, dense bands, a patchy basal lamina, intermediate filaments and specific junctions to SMCs. ICLCs were ultrastructurally differentiable from other......Interstitial Cajal-like cells (ICLCs) are speculated to be pacemakers in smooth muscle tissues. While the human thoracic duct (TD) is spontaneously active, the origin of this activity is unknown. We hypothesized that ICLCs could be present in the TD and using histological techniques...

  18. Notch-strengthening in two-dimensional foams

    NARCIS (Netherlands)

    Onck, P.R.

    Metallic foams show notch-strengthening behavior when analyzing double-edge notched specimen in compression and tension. A discrete microstructural model has been used to simulate the effect of notch depth and specimen size on the net-section-strength. The non-uniform deformation behavior is

  19. Strengthening Information Society Research Capacity Alliance ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2011-09-13

    The project is expected to strengthen the body of theoretically based, methodologically sound, interdisciplinary research on information society issues. Project ID. 106618. Project status. Closed. Start Date. September 13, 2011. End Date. August 12, 2014. Duration. 24 months. IDRC Officer. Smith, Matthew. Total funding.

  20. Experimental study on tunnel lining joints temporarily strengthened by SMA bolts

    International Nuclear Information System (INIS)

    Wu, Bo; Ou, Yunlong

    2014-01-01

    Shield tunnels have been widely used in city metros all over the world. During the long-term period of the metro operation, the joints of shield tunnel’s neighboring segments may degrade due to some environmental factors, leading to the increasing of the joint opening and some resulting adverse consequences. In this paper, a temporary strengthening method by using shape memory alloy (SMA) bolts is proposed and experimentally studied for the joints of neighboring segments, and a revised electric heating method which suits with the strengthening method is presented and experimentally validated for the SMA bolts. The purpose of the proposed temporary strengthening method is to create favorable conditions for the following permanent strengthening. Test results show that: (a) for the joints of shield tunnel’s neighboring segments, the strengthening method can effectively reduce the joint opening, joint deflection, concrete strain in joint’s compression zone, and strain of joint’s steel bolts; (b) the revised electric heating method can be used to heat the SMA rod to a temperature higher than the SMA’s austenite finish temperature quickly, and the average heating rate related to Type 2 inner resistance element is larger than that related to Type 1 inner resistance element; and (c) the reduction percentages of the joint opening increment, joint deflection, concrete strain in joint’s compression zone, and strain of joint’s steel bolts for Specimen I are all larger than those for Specimen II, implying that the less the joint opening is, the more significant the strengthening effect is. (paper)

  1. Strengthening of the Cooperative Framework for ANENT

    International Nuclear Information System (INIS)

    Han, K. W.; Lee, E. J.; Min, B. J.

    2007-01-01

    The Asian Network for Education in Nuclear Technology (ANENT) was established in February 2004 to promote nuclear education and training in Asia. Initially ANENT member countries cooperated with 5 group activities encompassing broad areas. As of 2006, the cooperative framework was strengthened in a way to focus on web-based nuclear education and training for a period of several years to come. In this context, the Nuclear Training Center (NTC) of KAERI has contributed, in particular, to the development of the ANENT web-portal including a cyber platform, and making available relevant courses and materials on the web-portal. This paper discusses details of the strengthened cooperative framework in terms of NTC's effort for realizing web-based education and training through regional networking

  2. Limit analysis on FRP-strengthened RC members

    Directory of Open Access Journals (Sweden)

    D. De Domenico

    2014-07-01

    Full Text Available Reinforced concrete (RC members strengthened with externally bonded fiber-reinforced-polymer (FRP plates are numerically investigated by a plasticity-based limit analysis approach. The key-concept of the present approach is to adopt proper constitutive models for concrete, steel reinforcement bars (re-bars and FRP strengthening plates according to a multi-yield-criteria formulation. This allows the prediction of concrete crushing, steel bars yielding and FRP rupture that may occur at the ultimate limit state. To simulate such limitstate of the analysed elements, two iterative methods performing linear elastic analyses with adaptive elastic parameters and finite elements (FEs description are employed. The peak loads and collapse mechanisms predicted for FRP-plated RC beams are validated by comparison with the corresponding experimental findings.

  3. Strengthening rural health placements for medical students ...

    African Journals Online (AJOL)

    Strengthening rural health placements for medical students: Lessons for South Africa ... rural health, primary healthcare and National Health Insurance strategies. ... preferential selection of students with a rural background, positioning rural ...

  4. Strengthening Democratic Governance through ICTs : Post Election ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Strengthening Democratic Governance through ICTs : Post Election ... has had several consequences, culminating in the disputed general elections of December 2007. ... Linking research to urban planning at the ICLEI World Congress 2018.

  5. Strategy of Strengthening Institutional Fishermen Groups for Increasing Income

    Directory of Open Access Journals (Sweden)

    Edy Yusuf Agunggunanto

    2016-10-01

    Full Text Available The community development and empowerment are two inseparable sides in the efforts to overcome the phenomenon of the fishermen communities, especially in the efforts to increase the welfare through the increasing income in the fishermen communities. One of the media in implementing the community development and empowerment is through the fishermen groups. The role of fishermen groups has not run optimally yet in improving the fishermen’s welfare, so it requires a strategy of developing the fishermen groups through the strategy of strengthening the economy in order to increase the fishermen’s income. This research aims to determine the priority of aspects to determine the strategies and to analyze the priority of strategy of strengthening the economy through the development of the institutional fishermen groups in order to increase the fishermen income in Central Java. The method of analysis in this research uses the Analytic Hierarchy Process (AHP. The result of AHP analysis indicates the priority of aspects in the strategy of strengthening the economy those are: aspects of participation,aspects of capital, aspects of partnership, and aspects of technology. The priority of alternatives in the strategy of strengthening the fishermen’s economy shows three sequences of 12 alternatives of strategies those are:  the  socialization of the importance of groups, the increase in the active participation, and the increase in the number of meetings.

  6. Strengthening and Stabilization of the Weak Water Saturated Soils Using Stone Columns

    Directory of Open Access Journals (Sweden)

    Sinyakov Leonid

    2016-01-01

    Full Text Available The article considers innovative modern materials and structures for strengthening of weak soils. In this paper describes a method of strengthening of weak saturated soils using stone columns. The method of calculating the physical-mechanical characteristics of reinforced soil mass is presented. Two approaches to determining the stress-strain state and timeframe of consolidation of strengthened soil foundation using the finite element technique in two-dimensional formulation are proposed. The first one approach it is a modeling of reinforced soil mass, where each pile is represented as a separate 2D stripe. The second approach is to the simulation of the strengthened mass the equivalent composite block with improved physical-mechanical characteristics. The use of the equivalent composite block can significantly reduce the time spent on the preparation of a design scheme. The results of calculations were compared. They show the allowable divergence of results of calculation by two methods were presented, and the efficiency of the strengthening of weak water saturated soils by stone column is proved.

  7. Strengthening primary healthcare through community involvement in ...

    African Journals Online (AJOL)

    Strengthening primary healthcare through community involvement in Cross River State, Nigeria: a descriptive study. Hilary Adie, Thomas Igbang, Akaninyene Otu, Ekanem Braide, Okpok Okon, Edet Ikpi, Charles Joseph, Alexander Desousa, Johannes Sommerfeld ...

  8. An Experimental Study on Strengthening of Reinforced Concrete Flexural Members using Steel Wire Mesh

    Directory of Open Access Journals (Sweden)

    Al Saadi Hamza Salim Mohammed

    2017-01-01

    Full Text Available One of the major challenges and contemporary research in the field of structural engineering is strengthening of existing structural elements using readily available materials in the market. Several investigations were conducted on strengthening of various structural components using traditional and advanced materials. Many researchers tried to enhance the reinforced concrete (RC beams strength using steel plate, Glass and Carbon Fibre Reinforced Polymers (GFRP & CFRP. For the reason that high weight to the strength ratio and compatibility in strength between FRP composites and steel bars, steel plates and GFRP and CFRP composites are not used for strengthening works practically. Hence, in this present work the suitability of using wire mesh for the purpose of strengthening the RC flexural members is studied by conducting experimental works. New technique of strengthening system using wire mesh with a view to improve sectional properties and subsequently flexural strength of RC beams is adopted in this work. The results for experimental and theoretical analysis were compared and found that good correlation exists between them. The experimental results indicate that RC beams strengthened with steel wire mesh are easy technique for strengthening of existing flexural members.

  9. Strengthening health workforce capacity through work-based training

    Directory of Open Access Journals (Sweden)

    Matovu Joseph KB

    2013-01-01

    Full Text Available Abstract Background Although much attention has been given to increasing the number of health workers, less focus has been directed at developing models of training that address real-life workplace needs. Makerere University School of Public Health (MakSPH with funding support from the Centers for Disease Control and Prevention (CDC developed an eight-month modular, in-service work-based training program aimed at strengthening the capacity for monitoring and evaluation (M&E and continuous quality improvement (CQI in health service delivery. Methods This capacity building program, initiated in 2008, is offered to in-service health professionals working in Uganda. The purpose of the training is to strengthen the capacity to provide quality health services through hands-on training that allows for skills building with minimum work disruptions while encouraging greater involvement of other institutional staff to enhance continuity and sustainability. The hands-on training uses practical gaps and challenges at the workplace through a highly participatory process. Trainees work with other staff to design and implement ‘projects’ meant to address work-related priority problems, working closely with mentors. Trainees’ knowledge and skills are enhanced through short courses offered at specific intervals throughout the course. Results Overall, 143 trainees were admitted between 2008 and 2011. Of these, 120 (84% from 66 institutions completed the training successfully. Of the trainees, 37% were Social Scientists, 34% were Medical/Nursing/Clinical Officers, 5.8% were Statisticians, while 23% belonged to other professions. Majority of the trainees (80% were employed by Non-Government Organizations while 20% worked with the public health sector. Trainees implemented 66 projects which addressed issues such as improving access to health care services; reducing waiting time for patients; strengthening M&E systems; and improving data collection and

  10. Nanoscale strengthening mechanisms in metallic thin film systems

    Science.gov (United States)

    Schoeppner, Rachel Lynn

    Nano-scale strengthening mechanisms for thin films were investigated for systems governed by two different strengthening techniques: nano-laminate strengthening and oxide dispersion strengthening. Films were tested under elevated temperature conditions to investigate changes in deformation mechanisms at different operating temperatures, and the structural stability. Both systems exhibit remarkable stability after annealing and thus long-term reliability. Nano-scale metallic multilayers with smaller layer thicknesses show a greater relative resistance to decreasing strength at higher temperature testing conditions than those with larger layer thicknesses. This is seen in both Cu/Ni/Nb multilayers as well as a similar tri-component bi-layer system (Cu-Ni/Nb), which removed the coherent interface from the film. Both nanoindentation and micro-pillar compression tests investigated the strain-hardening ability of these two systems to determine what role the coherent interface plays in this mechanism. Tri-layer films showed a higher strain-hardening ability as the layer thickness decreased and a higher strain-hardening exponent than the bi-layer system: verifying the presence of a coherent interface increases the strain-hardening ability of these multilayer systems. Both systems exhibited hardening of the room temperature strength after annealing, suggesting a change in microstructure has occurred, unlike that seen in other multilayer systems. Oxide dispersion strengthened Au films showed a marked increase in hardness and wear resistance with the addition of ZnO particles. The threshold for stress-induced grain-refinement as opposed to grain growth is seen at concentrations of at least 0.5 vol%. These systems exhibited stable microstructures during thermal cycling in films containing at least 1.0%ZnO. Nanoindentation experiments show the drop in hardness following annealing is almost completely attributed to the resulting grain growth. Four-point probe resistivity

  11. Seismic Strengthening of Carpentry Joints in Traditional Timber Structures

    International Nuclear Information System (INIS)

    Parisi, Maria A.; Cordie, Cinzia; Piazza, Maurizio

    2008-01-01

    The static and dynamic behavior of timber structures largely depends on their connections. In traditional timber construction, elements are usually connected with carpentry joints based on contact pressure and friction, often with only minor reinforcement generically intended to avoid disassembling. In current practice, interventions for the upgrading of carpentry joints are mainly based on empirical knowledge according to tradition. Often they produce a general strengthening of the connection, but are not specific for the case of seismic action. Strengthening on heuristic bases may be only partially effective or possibly disproportioned. The behavior of the carpentry joints most used in roof structures is examined. The birdsmouth joint, connecting rafters to the tie beam, has been studied first, characterizing its behavior numerically and experimentally in monotonic and cyclic conditions. Other forms of the rafter-to-tie connection, the double notch joint and the case of parallel rafters, are discussed. Some general criteria for the seismic strengthening of these joints are presented

  12. Seismic Strengthening of Carpentry Joints in Traditional Timber Structures

    Science.gov (United States)

    Parisi, Maria A.; Cordié, Cinzia; Piazza, Maurizio

    2008-07-01

    The static and dynamic behavior of timber structures largely depends on their connections. In traditional timber construction, elements are usually connected with carpentry joints based on contact pressure and friction, often with only minor reinforcement generically intended to avoid disassembling. In current practice, interventions for the upgrading of carpentry joints are mainly based on empirical knowledge according to tradition. Often they produce a general strengthening of the connection, but are not specific for the case of seismic action. Strengthening on heuristic bases may be only partially effective or possibly disproportioned. The behavior of the carpentry joints most used in roof structures is examined. The birdsmouth joint, connecting rafters to the tie beam, has been studied first, characterizing its behavior numerically and experimentally in monotonic and cyclic conditions. Other forms of the rafter-to-tie connection, the double notch joint and the case of parallel rafters, are discussed. Some general criteria for the seismic strengthening of these joints are presented.

  13. Adaptive force regulation of muscle strengthening rehabilitation device with magnetorheological fluids.

    Science.gov (United States)

    Dong, Shufang; Lu, Ke-Qian; Sun, Jian Qiao; Rudolph, Katherine

    2006-03-01

    In rehabilitation from neuromuscular trauma or injury, strengthening exercises are often prescribed by physical therapists to recover as much function as possible. Strengthening equipment used in clinical settings range from low-cost devices, such as sandbag weights or elastic bands to large and expensive isotonic and isokinetic devices. The low-cost devices are incapable of measuring strength gains and apply resistance based on the lowest level of torque that is produced by a muscle group. Resistance that varies with joint angle can be achieved with isokinetic devices in which angular velocity is held constant and variable torque is generated when the patient attempts to move faster than the device but are ineffective if a patient cannot generate torque rapidly. In this paper, we report the development of a versatile rehabilitation device that can be used to strengthen different muscle groups based on the torque generating capability of the muscle that changes with joint angle. The device is low cost, is smaller than other commercially available machines, and can be programmed to apply resistance that is unique to a particular patient and that will optimize strengthening. The core of the device, a damper with smart magnetorheological fluids, provides passive exercise force. A digital adaptive control is capable of regulating exercise force precisely following the muscle strengthening profile prescribed by a physical therapist. The device could be programmed with artificial intelligence to dynamically adjust the target force profile to optimize rehabilitation effects. The device provides both isometric and isokinetic strength training and can be developed into a small, low-cost device that may be capable of providing optimal strengthening in the home.

  14. Strengthening partnerships among Africa's science granting ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    The project will support regional training courses and on-site coaching to strengthen the capacity of participating councils to design and manage collaborative agreements. It will also co-fund demand-led collaborative research projects in selected areas of interest to the private sector. Sharing of evidence, lessons learned ...

  15. Delamination of carbon-fiber strengthening layer from concrete beam during deformation (infrared thermography)

    OpenAIRE

    Shardakov, I. N.; Shestakov, A. P.; Bykov, A.A.

    2016-01-01

    Technology of strengthening reinforced concrete structures with composite materials has found wide application. The effectiveness of strengthening of concrete structures with externally bonded reinforcement is supported by a great deal of experimental evidence. However, the problem of serviceability of such structures has not been adequately explored. The present work describes the results of experimental studies on the loadcarrying capacity of concrete beams strengthened with carbon fiber re...

  16. Coniferyl aldehyde attenuates radiation enteropathy by inhibiting cell death and promoting endothelial cell function.

    Science.gov (United States)

    Jeong, Ye-Ji; Jung, Myung Gu; Son, Yeonghoon; Jang, Jun-Ho; Lee, Yoon-Jin; Kim, Sung-Ho; Ko, Young-Gyo; Lee, Yun-Sil; Lee, Hae-June

    2015-01-01

    Radiation enteropathy is a common complication in cancer patients. The aim of this study was to investigate whether radiation-induced intestinal injury could be alleviated by coniferyl aldehyde (CA), an HSF1-inducing agent that increases cellular HSP70 expression. We systemically administered CA to mice with radiation enteropathy following abdominal irradiation (IR) to demonstrate the protective effects of CA against radiation-induced gastrointestinal injury. CA clearly alleviated acute radiation-induced intestinal damage, as reflected by the histopathological data and it also attenuated sub-acute enteritis. CA prevented intestinal crypt cell death and protected the microvasculature in the lamina propria during the acute and sub-acute phases of damage. CA induced HSF1 and HSP70 expression in both intestinal epithelial cells and endothelial cells in vitro. Additionally, CA protected against not only the apoptotic cell death of both endothelial and epithelial cells but also the loss of endothelial cell function following IR, indicating that CA has beneficial effects on the intestine. Our results provide novel insight into the effects of CA and suggest its role as a therapeutic candidate for radiation-induced enteropathy due to its ability to promote rapid re-proliferation of the intestinal epithelium by the synergic effects of the inhibition of cell death and the promotion of endothelial cell function.

  17. STRENGTHENING OF TRENCH COVER PLATES FOR SWITCHGEAR BUILDING

    International Nuclear Information System (INIS)

    M.S. RUBEN

    2000-01-01

    The objective of this calculation is to strengthen the existing trench cover plates of the Electrical Switchgear Building (BLDG 5010) of the Exploratory Studies Facility. A remodeling effort will change the portion of the facility that has the trenches for electrical cables to a craft/shop area. The users of the building will be using a forklift in this area (Clark CGP 30 forklift with a capacity of 3 tons). The trench covers require strengthening to support the wheel loads from the forklift. The output of this calculation will be sketches revising the floor plate details of DWG YMP-025-1-7007-ST103,2. (Details 4 and 5)

  18. Strengthening masonry walls made of brick blocks with FRCM composites

    Directory of Open Access Journals (Sweden)

    Radovanović Željka

    2015-01-01

    Full Text Available Results of testing more types of masonry walls made of brick blocks with the aim to define their mechanical characteristics and possibilities of external strengthening of walls with FRCM composites are presented in this paper. The characteristic compressive strengths, elasticity modulus and shear strengths of the various types of the walls were obtained on the basis of these testing results. Comparison between experimental results and values obtained by analytical approach in accordance with the current standard, European standards EN 1996 and the American standard ACI 530 is presented in this paper. After testing walls with application of compressive forces on the walls diagonal the cracked walls samples have been strengthened with selected types of FRCM composites. It was determined that the shear resistance of the walls after strengthening has increased significantly.

  19. The prescriptions from Shenghui soup enhanced neurite growth and GAP-43 expression level in PC12 cells.

    Science.gov (United States)

    Zhang, Qi; Zhang, Zi-Jian; Wang, Xing-Hua; Ma, Jie; Song, Yue-Han; Liang, Mi; Lin, Sen-Xiang; Zhao, Jie; Zhang, Ao-Zhe; Li, Feng; Hua, Qian

    2016-09-20

    Shenghui soup is a traditional Chinese herbal medicine used in clinic for the treatment of forgetfulness. In order to understanding the prescription principle, the effects of "tonifying qi and strengthening spleen" group (TQSS) including Poria cocos (Schw.) Wolf. and Panax ginseng C.A.Mey and "eliminating phlegm and strengthening intelligence" group (EPSI) composed of Polygala tenuifolia Willd., Acorus calamus L. and Sinapis alba L from the herb complex on neurite growth in PC12 cells, two disassembled prescriptions derived from Shenghui soup and their molecular mechanisms were investigated. Firstly, CCK-8 kit was used to detect the impact of the two prescriptions on PC12 cell viability; and Flow cytometry was performed to measure the cell apoptosis when PC12 cells were treated with these drugs. Secondly, the effect of the two prescriptions on the differentiation of PC12 cells was observed. Finally, the mRNA and protein expression levels of GAP-43 were analyzed by RT-PCR and western blot, respectively. "Tonifying qi and strengthening spleen" prescription decreased cell viability in a dose-dependent manner, but had no significant effect on cell apoptosis. Meanwhile, it could improve neurite growth and elevate the mRNA and protein expression level of GAP-43. "Eliminating phlegm and strengthening intelligence" prescription also exerted the similar effects on cell viability and apoptosis. Furthermore, it could also enhance cell neurite growth, with a higher expression level of GAP-43 mRNA and protein. "Tonifying qi and strengthening spleen" and "eliminating phlegm and strengthening intelligence" prescriptions from Shenghui soup have a positive effect on neurite growth. Their effects are related to the up-regulating expression of GAP-43.

  20. Does transparent government agencies strengthen trust?

    NARCIS (Netherlands)

    Grimmelikhuijsen, S.G.

    2009-01-01

    Trust in government has been shown to be volatile in recent years and Internet transparency is seen as a solution to strengthen trust. However, critics argue that transparency will only lead to less trust, and sceptics say that it has no effect at all. This debate on transparency is lacking

  1. Seismic strengthening of the ILL High Flux Reactor building

    International Nuclear Information System (INIS)

    Germane, Lionel; Plewinski, Francois; Thiry, Jean-Michel

    2006-01-01

    The Institut Max von Laue - Paul Langevin is an international research organisation and world leader in neutron science and technology. Since 1971 it has been operating the ILL HFR (High-Flux Reactor), the most intense continuous neutron source in the world. The ILL is governed by an international cooperation agreement between France, Germany and the United Kingdom; the fourth ten-year extension to the agreement was signed at the end of 2002, thus ensuring that the Institute will continue to operate until at least the end of 2013. In 2002 the facility underwent a general safety review, including an assessment of the impact of a safe shutdown earthquake. A broader programme for upgrading the installations and improving safety levels is now under way. As this has been treated in another paper, we will focus here on the seismic study carried out on the reactor building. The paper has the following contents: 1. Context; 1.1. Presentation of the ILL; 1.2. Description of the installations; 1.3. Safety objectives in the event of an earthquake; 1.4. Safety functions to be guaranteed in the event of an earthquake; 1.5. Safety functions required of the building; 2. Description of the building; 3. Organisation of the project; 3.1. Background; 3.2. Organisation; 4. General Methodology of the studies; 5. Progress of the studies; 5.1. Definition of the strengthening measures; 5.2. Validation of the strengthening option; 6. Seismic strengthening of the building; 6.1. Description of the strengthening measures; 6.2. Implementation of the strengthening measures; 6.2.1. Pilot operation; 6.2.2. Main operation; 7. Conclusion. To summarize, the presence of specialists in the ILL team, and the fact that the initial studies were performed by the project team itself, improved our general understanding of the issues and facilitated dialogue and exchange between all those involved (operators, technicians, outside experts, technical contractors and the French safety authorities). Everyone was

  2. Strengthening Science-based Environmental Policy Development in ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Strengthening Science-based Environmental Policy Development in Burma's Democratic ... IDRC is providing funding to Simon Fraser University to support a network of ... The project will also encourage and assist in the creation of a business ...

  3. Strengthening Governance in Health Systems for Reproductive ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Home · What we do ... As a result, Pakistan's health system has suffered and health service delivery has worsened. ... This four-year project aims to strengthen health systems governance for reproductive health and rights in Pakistan.

  4. Tumour necrosis factor-alpha (TNF-alpha) transcription and translation in the CD4+ T cell-transplanted scid mouse model of colitis

    DEFF Research Database (Denmark)

    Williams, A M; Whiting, C V; Bonhagen, K

    1999-01-01

    The adoptive transfer of activated CD4+ alpha/beta T cell blasts from the spleens of immunocompetent C.B-17+/+ or BALB/cdm2 mice into C.B-17scid/scid (scid) mice induces a colitis in the scid recipient within 8 weeks, which progresses to severe disease within 16 weeks. T cells isolated from......-labelled riboprobes were used. The prominent myeloid cell infiltrate in diseased tissues comprised F4/80+, Mac-l+ macrophages, neutrophils, dendritic cells and activated macrophages. TNF-alpha transcription and translation were associated with activated macrophages in the lamina propria. Activated macrophages...

  5. Plastic Changes in the Spinal Cord in Motor Neuron Disease

    Directory of Open Access Journals (Sweden)

    Francesco Fornai

    2014-01-01

    Full Text Available In the present paper, we analyze the cell number within lamina X at the end stage of disease in a G93A mouse model of ALS; the effects induced by lithium; the stem-cell like phenotype of lamina X cells during ALS; the differentiation of these cells towards either a glial or neuronal phenotype. In summary we found that G93A mouse model of ALS produces an increase in lamina X cells which is further augmented by lithium administration. In the absence of lithium these nestin positive stem-like cells preferentially differentiate into glia (GFAP positive, while in the presence of lithium these cells differentiate towards a neuron-like phenotype (βIII-tubulin, NeuN, and calbindin-D28K positive. These effects of lithium are observed concomitantly with attenuation in disease progression and are reminiscent of neurogenetic effects induced by lithium in the subependymal ventricular zone of the hippocampus.

  6. High temperature mechanical properties of unirradiated dispersion strengthened copper

    International Nuclear Information System (INIS)

    Gentzbittel, J.M.; Rigollet, C.; Robert, G.

    1994-01-01

    Oxide Dispersion Strengthened (ODS) copper material, due to its excellent thermal conductivity associated with a high temperature strength is a candidate material for structural applications as divertor plasma facing components of thermonuclear fusion reactor. Tensile and creep results of oxide dispersion strengthened copper are presented. The most important features of ODS copper high temperature behaviour are the high strength corresponding to low creep rates, high stress creep rate dependence, a poor ductility and a brittleness which result in a premature creep fracture at high applied stress. (R.P.) 2 refs.; 6 figs

  7. Confocal Analysis of Nuclear Lamina Behavior during Male Meiosis and Spermatogenesis in Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Fabiana Fabbretti

    Full Text Available Lamin family proteins are structural components of a filamentous framework, the nuclear lamina (NL, underlying the inner membrane of nuclear envelope. The NL not only plays a role in nucleus mechanical support and nuclear shaping, but is also involved in many cellular processes including DNA replication, gene expression and chromatin positioning. Spermatogenesis is a very complex differentiation process in which each stage is characterized by nuclear architecture dramatic changes, from the early mitotic stage to the sperm differentiation final stage. Nevertheless, very few data are present in the literature on the NL behavior during this process. Here we show the first and complete description of NL behavior during meiosis and spermatogenesis in Drosophila melanogaster. By confocal imaging, we characterized the NL modifications from mitotic stages, through meiotic divisions to sperm differentiation with an anti-laminDm0 antibody against the major component of the Drosophila NL. We observed that continuous changes in the NL structure occurred in parallel with chromatin reorganization throughout the whole process and that meiotic divisions occurred in a closed context. Finally, we analyzed NL in solofuso meiotic mutant, where chromatin segregation is severely affected, and found the strict correlation between the presence of chromatin and that of NL.

  8. Correlating Corneal Biomechanics and Ocular Biometric Properties with Lamina Cribrosa Measurements in Healthy Subjects.

    Science.gov (United States)

    Pérez Bartolomé, Francisco; Martínez de la Casa, Jose María; Camacho Bosca, Irene; Sáenz-Francés, Federico; Aguilar Munoa, Soledad; Martín Juan, Alberto; Garcia-Feijoo, Julian

    2018-01-01

    To examine interrelations between corneal biomechanics, ocular biometric variables and optic disc size (ODS), lamina cribosa depth (LCD) or thickness (LCT) in a healthy population. In a cross-sectional case-control study, the following measurements were made in 81 eyes of 81 participants: axial length, anterior chamber depth, lens thickness, and central corneal thickness using the optical biometer Lenstar LS900; and corneal hysteresis (CH), corneal resistance factor (CRF), Goldman-correlated intraocular pressure (IOPg), and corneal-compensated IOP (IOPcc) using the Ocular Response Analyzer. Serial horizontal enhanced depth imaging optical coherence tomography (EDI OCT) B-scans of the optic nerve head were obtained in each participant. Mean ODS, mean LCD, and mean LCT were measured in 11 equally spaced horizontal B-scans, excluding the LC insertion area under Bruch's membrane and scleral rim. LCD was measured in 74 of 81 eyes (91.36%); LCT in 60/81 (75.3%); ODS in 81/81 (100%). CRF was poorly, but significantly, correlated with LCT (Pearson's R = 0.264; P = 0.045). IOPcc, IOPg, CH, and ocular biometrics variables were poorly (non-significantly) correlated with LCD, LCT, and ODS. CRF was poorly but directly correlated with LCT. No association was detected between CH or ocular biometric variables and ODS, LCD, or LCT.

  9. Fatigue behaviour analysis for the durability prequalification of strengthening mortars

    International Nuclear Information System (INIS)

    Bocca, P; Grazzini, A; Masera, D

    2011-01-01

    An innovative laboratory procedure used as a preliminary design stage for the pre-qualification of strengthening mortars applied to historical masonry buildings is described. In the analysis of the behaviour of masonry structures and their constituent materials, increasing importance has been assumed by the study of the long-term evolution of deformation and mechanical characteristics, which may be affected by both loading and environmental conditions. Through static and fatigue tests on mixed specimens historical brick-reinforced mortar it has been possible to investigate the durability of strengthening materials, in order to select, from a range of alternatives, the most suitable for the historical masonry. Cyclic fatigue stress has been applied to accelerate the static creep and to forecast the corresponding creep behaviour of the historical brick-strengthening mortar system under static long-time loading. This methodology has proved useful in avoiding the errors associated with materials that are not mechanically compatible and guarantees the durability of strengthening work. The experimental procedure has been used effectively in the biggest restoration building site in Europe, the Royal Palace of Venaria, and it is in progress of carrying out at the Special Natural Reserve of the Sacro Monte di Varallo, in Piedmont (Italy).

  10. Strengthening Agricultural Research Capacity for Viable Extension ...

    African Journals Online (AJOL)

    Strengthening Agricultural Research Capacity for Viable Extension Policies in Nigeria: An Exploration of Ricoeur's Hermeneutic Theory for Analysing Extension Research. ... Progressively more, researchers use hermeneutic philosophy to inform the conduct of interpretive research. Analogy between the philosophical ...

  11. Strengthening entrepreneurship through coaching and developing competencies

    NARCIS (Netherlands)

    Beldman, A.C.G.

    2011-01-01

    Strengthening entrepreneurship is an important strategy for stimulating the transition to sustainable agriculture. But how is that done? One example is the Interactive Strategic Management method, which supports entrepreneurs in the creation and execution of future-focused strategies.

  12. CD90-positive cells, an additional cell population, produce laminin α2 upon transplantation to dy3k/dy3k mice

    International Nuclear Information System (INIS)

    Fukada, So-ichiro; Yamamoto, Yukiko; Segawa, Masashi; Sakamoto, Kenta; Nakajima, Mari; Sato, Masaki; Morikawa, Daisuke; Uezumi, Akiyoshi; Miyagoe-Suzuki, Yuko; Takeda, Shin'ichi; Tsujikawa, Kazutake; Yamamoto, Hiroshi

    2008-01-01

    Laminin α2 is a component of skeletal and cardiac muscle basal lamina. A defect of the laminin α2 chain leads to severe congenital muscular dystrophy (MDC1A) in humans and dy/dy mice. Myogenic cells including myoblasts, myotubes, and myofibers in skeletal muscle are a possible source of the laminin α2 chain, and myogenic cells are thus proposed as a cell source for congenital muscular dystrophy therapy. However, we observed production of laminin α2 in non-myogenic cells of normal mice, and we could enrich these laminin α2-producing cells in CD90 + cell fractions. Intriguingly, the number of CD90 + cells increased dramatically during skeletal muscle regeneration in mice. This fraction did not include myogenic cells but exhibited a fibroblast-like phenotype. Moreover, these cells were resident in skeletal muscle, not derived from bone marrow. Finally, the production of laminin α2 in CD90 + cells was not dependent on fusion with myogenic cells. Thus, CD90 + cells are a newly identified additional cell fraction that increased during skeletal muscle regeneration in vivo and could be another cell source for therapy for lama2-deficient muscular dystrophy

  13. Equine tracheal epithelial membrane strips - An alternate method for examining epithelial cell arachidonic acid metabolism

    International Nuclear Information System (INIS)

    Gray, P.R.; Derksen, F.J.; Robinson, N.E.; Peter-Golden, M.L.

    1990-01-01

    Arachidonic acid metabolism by tracheal epithelium can be studied using enzymatically dispersed cell suspensions or cell cultures. Both techniques require considerable tissue disruption and manipulation and may not accurately represent in vivo activity. The authors have developed an alternate method for obtaining strips of equine tracheal epithelium without enzymatic digestion. In the horse, a prominent elastic lamina supports the tracheal epithelium. By physical splitting this lamina, they obtained strips (≤12 x 1.5 cm) of pseudostratified columnar epithelium attached to a layer of elastic tissue 30-100 μm thick. Epithelial strips (1.2 x 0.5 cm) were attached to plexiglass rods and incubated with [ 3 H]arachidonic acid in M199 medium (0.5 μCi/ml) for 24 hours at 37C. The strips incorporated 36±4% (mean ± SEM) of the total radioactivity and released 8.0±1.2% of incorporated radioactivity when stimulated by 5.0 μM calcium ionophore A23187. The extracted supernatant was processed using HPLC, resulting in peaks of radioactivity that co-eluted with authentic PGE 2 , PGF 2 α, and 12-HETE standards. The greatest activity corresponded to the PGE 2 and PGF 2 α standards, which is a similar pattern to that reported for cultured human tracheal epithelium

  14. The response of dispersion-strengthened copper alloys to high fluence neutron irradiation at 415 degrees C

    International Nuclear Information System (INIS)

    Edwards, D.J.; Newkirk, J.W.; Garner, F.A.; Hamilton, M.L.; Nadkarni, A.; Samal, P.

    1993-01-01

    Various oxide-dispersion-strengthened copper alloys have been irradiated to 150 dpa at 415 degrees C in the Fast Flux Test Facility (FFTF). The Al 2 O 3 -strengthened GlidCop TM alloys, followed closely by a HfO 2 -strengthened alloy, displayed the best swelling resistance, electrical conductivity, and tensile properties. The conductivity of the HfO 2 -strengthened alloy reached a plateau at the higher levels of irradiation, instead of exhibiting the steady decrease in conductivity observed in the other alloys. A high initial oxygen content results in significantly higher swelling for a series of castable oxide-dispersion-strengthened alloys, while a Cr 2 O 3 -strengthened alloy showed poor resistance to radiation

  15. Interstitial cells of Cajal in human small intestine. Ultrastructural identification and organization between the main smooth muscle layers

    DEFF Research Database (Denmark)

    Rumessen, J J; Thuneberg, L

    1991-01-01

    with elastin fibers. The organization shown in this study strongly supports the concept of interstitial cells of Cajal as important regulatory cells also in the human small intestine. The characteristic cytology and organization of interstitial cells of Cajal may provide a basis for future morphological......Previous morphological and electrophysiological studies have supported the hypothesis that interstitial cells of Cajal have important regulatory (pacemaker) functions in the gut. In the current study, interstitial cells of Cajal associated with Auerbach's plexus in human small intestine were...... studied. Freshly resected intestine was examined by light and electron microscopy. The interstitial cells of Cajal resembled modified smooth muscle cells. They had caveolae and dense bodies, an incomplete basal lamina, a very well-developed smooth endoplasmic reticulum, and abundant intermediate (10 nm...

  16. Connections between EM2-containing terminals and GABA/μ-opioid receptor co-expressing neurons in the rat spinal trigeminal caudal nucleus

    Science.gov (United States)

    Li, Meng-Ying; Wu, Zhen-Yu; Lu, Ya-Cheng; Yin, Jun-Bin; Wang, Jian; Zhang, Ting; Dong, Yu-Lin; Wang, Feng

    2014-01-01

    Endomorphin-2 (EM2) demonstrates a potent antinociceptive effect via the μ-opioid receptor (MOR). To provide morphological evidence for the pain control effect of EM2, the synaptic connections between EM2-immunoreactive (IR) axonal terminals and γ-amino butyric acid (GABA)/MOR co-expressing neurons in lamina II of the spinal trigeminal caudal nucleus (Vc) were investigated in the rat. Dense EM2-, MOR- and GABA-IR fibers and terminals were mainly observed in lamina II of the Vc. Within lamina II, GABA- and MOR-neuronal cell bodies were also encountered. The results of immunofluorescent histochemical triple-staining showed that approximately 14.2 or 18.9% of GABA-IR or MOR-IR neurons also showed MOR- or GABA-immunopositive staining in lamina II; approximately 45.2 and 36.1% of the GABA-IR and MOR-IR neurons, respectively, expressed FOS protein in their nuclei induced by injecting formalin into the left lower lip of the mouth. Most of the GABA/MOR, GABA/FOS, and MOR/FOS double-labeled neurons made close contacts with EM2-IR fibers and terminals. Immuno-electron microscopy confirmed that the EM2-IR terminals formed synapses with GABA-IR or MOR-IR dendritic processes and neuronal cell bodies in lamina II of the Vc. These results suggest that EM2 might participate in pain transmission and modulation by binding to MOR-IR and GABAergic inhibitory interneuron in lamina II of the Vc to exert inhibitory effect on the excitatory interneuron in lamina II and projection neurons in laminae I and III. PMID:25386121

  17. Preparation of Si and O co-solution strengthened Ti alloys by using rice husks as SiO2 resource and quantitative descriptions on their strengthening effects

    Science.gov (United States)

    Jia, Lei; Chen, Jiang-xian; Lu, Zhen-lin; Li, Shu-feng; Umeda, Junko; Kondoh, Katsuyoshi

    2018-04-01

    Ti alloys strengthened by both Si and O solutes were prepared by powder metallurgy method from pure Ti and amorphous SiO2 powder obtained by combusting rice husks. At the same time, Ti alloys singly strengthened by Si or O were also prepared for studying the strengthening effect of Si and O solutes. Results showed that amorphous SiO2 powder originated from rice husks could almost fully dissolve into pure Ti matrix when the content was not higher than 1.0 wt%, while higher content of SiO2 addition resulted in the formation of Ti5Si3 intermetallics. Si and O elements leaded to negative and positive distortion of Ti lattice, and the influencing degrees were ‑0.02 and +0.014 Å/wt% for lattice constant a, while ‑0.05 and +0.046 Å/wt% for constant c, respectively. Solid solution of Si and O would also result in the increase of hardness, which was 98.5 and 209.43 HV/wt%, respectively. When Si and O were co-exsited in Ti matrix, the negative and positive distortion cancelled each other, while the strengthening effect did not cancel but enhance each other.

  18. Ultrastructure of interstitial cells of Cajal associated with deep muscular plexus of human small intestine

    DEFF Research Database (Denmark)

    Rumessen, J J; Mikkelsen, H B; Thuneberg, L

    1992-01-01

    Evidence showing that interstitial cells of Cajal have important regulatory functions in the gut musculature is accumulating. In the current study, the ultrastructure of the deep muscular plexus and associated interstial cells of Cajal in human small intestine were studied to provide a reference...... a continuous basal lamina, caveolae, intermediate filaments, dense bodies, dense bands, and a well-developed subsurface smooth endoplasmic reticulum), but the arrangement of organelles was clearly different, and cisternae of granular endoplasmic reticulum were abundant. Interstitial cells of Cajal were......, and only few gap junctions with other interstitial cells of Cajal or with the musculature were observed. Compared with interstitial cells of Cajal from other mammals, those associated with the deep muscular plexus in the human small intestine more closely resemble smooth muscle cells...

  19. Retrofitting Heritage Buildings by Strengthening or Using Seismic Isolation

    International Nuclear Information System (INIS)

    Danieli, Moshe; Bloch, Jacob; Ribakov, Yuri

    2008-01-01

    Many heritage buildings in the Mediterranean area include stone domes as a structural and architectural element. Present stage of these buildings often requires strengthening or retrofitting in order to increase their seismic resistance. Strengthening is possible by casting above existing dome a thin reinforced concrete shell with a support ring. It yields reduction of stresses and strains in the dome. This paper deals with examples of actual restoration and strengthening of three structures in Georgia, two of them damaged by an earthquake in 1991, (a temple in Nikortzminda and a synagogue in Oni, built in 11 th and 19 r century, respectively) and a mosque in Akhaltzikhe, built in 18th century. Retrofitting of these structures was aimed at preservation of initial geometry and appearance by creating composite (stone--reinforced concrete, or stone--shotcrete) structures, which were partially or fully hidden. Further improving of seismic response may be achieved by using hybrid seismic isolation decreasing the seismic forces and adding damping. A brief description of the design procedure for such cases is presented

  20. Full Scale RC Beam-Column Joints Strengthened with Steel Reinforced Polymer Systems

    Science.gov (United States)

    De Vita, Alessandro; Napoli, Annalisa; Realfonzo, Roberto

    2017-07-01

    This paper presents the results of an experimental campaign performed at the Laboratory of Materials and Structural Testing of the University of Salerno (Italy) in order to investigate the seismic performance of RC beam-column joints strengthened with Steel Reinforced Polymer (SRP) systems. With the aim to represent typical façade frames’ beam-column subassemblies found in existing RC buildings, specimens were provided with two short beam stubs orthogonal to the main beam and were designed with inadequate seismic details. Five members were strengthened by using two different SRP layouts while the remaining ones were used as benchmarks. Once damaged, two specimens were also repaired, retrofitted with SRP and subjected to cyclic test again. The results of cyclic tests performed on SRP strengthened joints are examined through a comparison with the outcomes of the previous experimental program including companion specimens not provided with transverse beam stubs and strengthened by Carbon Fiber Reinforced Polymer (CFRP) systems. In particular, both qualitative and quantitative considerations about the influence of the confining effect provided by the secondary beams on the joint response, the suitability of all the adopted strengthening solutions (SRP/CFRP systems), the performances and the failure modes experienced in the several cases studied are provided.

  1. Strengthening community participation in reducing GHG emission from forest and peatland fire

    Science.gov (United States)

    Thoha, A. S.; Saharjo, B. H.; Boer, R.; Ardiansyah, M.

    2018-02-01

    Strengthening community participation is needed to find solutions to encourage community more participate in reducing Green House Gas (GHG) from forest and peatland fire. This research aimed to identify stakeholders that have the role in forest and peatland fire control and to formulate strengthening model of community participation through community-based early warning fire. Stakeholder mapping and action research were used to determine stakeholders that had potential influence and interest and to formulate strengthening model of community participation in reducing GHG from forest and peatland fire. There was found that position of key players in the mapping of stakeholders came from the government institution. The existence of community-based fire control group can strengthen government institution through collaborating with stakeholders having strong interest and influence. Moreover, it was found several local knowledge in Kapuas District about how communities predict drought that have potential value for developing the community-based early warning fire system. Formulated institutional model in this research also can be further developed as a model institution in the preservation of natural resources based on local knowledge. In conclusion, local knowledge and community-based fire groups can be integrated within strengthening model of community participation in reducing GHG from forest and peatland fire.

  2. Strengthening Family Practices for Latino Families

    Science.gov (United States)

    Chartier, Karen G.; Negroni, Lirio K.; Hesselbrock, Michie N.

    2010-01-01

    This study examined the effectiveness of a culturally adapted Strengthening Families Program (SFP) for Latinos to reduce risks for alcohol and drug use in children. Latino families, predominantly Puerto Rican, with a 9- to 12-year-old child and a parent(s) with a substance abuse problem participated in the study. Pre- and post-tests were conducted…

  3. Shear strength of reinforced concrete beams strengthened by P.B.O. fiber mesh under loading

    Directory of Open Access Journals (Sweden)

    Blikharskyy Zinoviy

    2017-01-01

    Full Text Available This article presents experimental study of sheer strength of reinforced concrete beams without transverse steel reinforcement, which strengthened by composite materials. The feature of tests is that the beams’ strengthening is made under simultaneous action of loading. The research program involves a series of test beams with size 2100 × 200 × 100 mm and which contains control sample and three reinforced samples by reinforcing FRCM system. FRCM system consisting of two components: mineral mortar based on modified cement Ruredil X Mesh M750 and reinforcing P.B.O. fiber mesh Ruredil X Mesh Gold (Italy. The strength research of test samples was carried out with the shear distance to effective depth ratio a/d = 2. The strengthening loading levels were selected at 0.0, 0.3, 0.5 from shear strength of non strengthened control sample. As a result of experimental studies we found that during strengthening design the inclined cross section of beams we should take into account the existing level of loading. Using the strengthening system Ruredil X Mesh Gold the strengthening effect is reduced at 2.8 to 2.9 times while the existing level of loading increase from 0 to 50%.

  4. Behavior of Insulated Carbon-FRP-Strengthened RC Beams Exposed to Fire

    Science.gov (United States)

    Sayin, B.

    2014-09-01

    There are two main approaches to improving the fire resistance of fiber-reinforced polymer (FRP) systems. While the most common method is to protect or insulate the FRP system, an other way is to use fibers and resins with a better fire performance. This paper presents a numerical investigation into the five protection behavior of insulated carbon-fiber-reinforced-polymer (CFRP)-strengthened reinforced concrete (RC) beams. The effects of external loading and thermal expansion of materials at elevated temperatures are taken into consideration in a finite-element model. The validity of the numerical model is demonstrated with results from an existing experimental study on insulated CFRP-strengthened RC beams. Conclusions of this investigation are employed to predict the structural behavior of CFRP-strengthened concrete structures.

  5. Strengthening Equity through Applied Research Capacity Building ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    There exists limited understanding of how e-Health solutions are perceived, designed, implemented and used. ... The Strengthening Equity through Applied Research Capacity Building in e-Health (SEARCH) program will cultivate local research capacity to examine e-health and ... Liverpool School of Tropical Medicine.

  6. Strengthening Environmental Economics Capacity in Research on ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Strengthening Environmental Economics Capacity in Research on Climate Change Adaptation ... They will develop environmental economics methods to address specific climate change challenges caused by extreme weather stressors. ... Initiative Villes ciblées : gestion des déchets urbains à Cochabamba, en Bolivie.

  7. Flexural Behavior of Self-Compacting RC Continuous Beams Strengthened by CFRP Sheets

    Directory of Open Access Journals (Sweden)

    Sabih Z. Al-Sarraf

    2018-01-01

    Full Text Available This search presented an experimental study of the flexural behavior of self-compacting reinforced concrete continuous beams externally strengthened by carbon fiber reinforced polymer (CFRP Sheets. The practical study contained eight self-compacting reinforced concrete continuous beams (with two span, each span had (1500 mm length and (150x250 mm cross sectional dimensions. Seven of these beams strengthened externally by CFRP sheets with and without external anchorage. The experimental variables included location of CFRP sheets and anchor type and location. The results, shows that the beams strengthened externally by CFRP sheets provided improvement in ultimate loads reached (60.71%. The usage of CFRP in the anchorage zone indicated an effective method in comparison to increasing the CFRP sheets lengths or extending them up to the support or under the loading points. Test results also showed that side strengthening provided an effective tool for increasing the load at the cracking stage and also the load capacity and reducing flexural crack widths.

  8. Polyphenol-Rich Propolis Extracts Strengthen Intestinal Barrier Function by Activating AMPK and ERK Signaling

    Directory of Open Access Journals (Sweden)

    Kai Wang

    2016-05-01

    Full Text Available Propolis has abundant polyphenolic constituents and is used widely as a health/functional food. Here, we investigated the effects of polyphenol-rich propolis extracts (PPE on intestinal barrier function in human intestinal epithelial Caco-2 cells, as well as in rats. In Caco-2 cells, PPE increased transepithelial electrical resistance and decreased lucifer yellow flux. PPE-treated cells showed increased expression of the tight junction (TJ loci occludin and zona occludens (ZO-1. Confocal microscopy showed organized expressions in proteins related to TJ assembly, i.e., occludin and ZO-1, in response to PPE. Furthermore, PPE led to the activation of AMPK, ERK1/2, p38, and Akt. Using selective inhibitors, we found that the positive effects of PPE on barrier function were abolished in cells in which AMPK and ERK1/2 signaling were inhibited. Moreover, rats fed a diet supplemented with PPE (0.3% in the diet exhibited increased colonic epithelium ZO-1 expression. Overall, these data suggest that PPE strengthens intestinal barrier function by activating AMPK and ERK signaling and provide novel insights into the potential application of propolis for human gut health.

  9. Competing indentation deformation mechanisms in glass using different strengthening methods

    Directory of Open Access Journals (Sweden)

    Jian Luo

    2016-11-01

    Full Text Available Chemical strengthening via ion exchange, thermal tempering, and lamination are proven techniques for strengthening of oxide glasses. For each of these techniques, the strengthening mechanism is conventionally ascribed to the linear superposition of the compressive stress profile on the glass surface. However, in this work we use molecular dynamics simulations to reveal the underlying indentation deformation mechanism beyond the simple linear superposition of compressive and indentation stresses. In particular, the plastic zone can be dramatically different from the commonly assumed hemispherical shape, which leads to a completely different stress field and resulting crack system. We show that the indentation-induced fracture is controlled by two competing mechanisms: the compressive stress itself and a potential reduction in free volume that can increase the driving force for crack formation. Chemical strengthening via ion exchange tends to escalate the competition between these two effects, while thermal tempering tends to reduce it. Lamination of glasses with differential thermal expansion falls in between. The crack system also depends on the indenter geometry and the loading stage, i.e., loading vs. after unloading. It is observed that combining thermal tempering or high free volume content with ion exchange or lamination can impart a relatively high compressive stress and reduce the driving force for crack formation. Therefore, such a combined approach might offer the best overall crack resistance for oxide glasses.

  10. RC beams shear-strengthened with fabric-reinforced-cementitious-matrix (FRCM) composite

    Science.gov (United States)

    Loreto, Giovanni; Babaeidarabad, Saman; Leardini, Lorenzo; Nanni, Antonio

    2015-12-01

    The interest in retrofit/rehabilitation of existing concrete structures has increased due to degradation and/or introduction of more stringent design requirements. Among the externally-bonded strengthening systems fiber-reinforced polymers is the most widely known technology. Despite its effectiveness as a material system, the presence of an organic binder has some drawbacks that could be addressed by using in its place a cementitious binder as in fabric-reinforced cementitious matrix (FRCM) systems. The purpose of this paper is to evaluate the behavior of reinforced concrete (RC) beams strengthened in shear with U-wraps made of FRCM. An extensive experimental program was undertaken in order to understand and characterize this composite when used as a strengthening system. The laboratory results demonstrate the technical viability of FRCM for shear strengthening of RC beams. Based on the experimental and analytical results, FRCM increases shear strength but not proportionally to the number of fabric plies installed. On the other hand, FRCM failure modes are related with a high consistency to the amount of external reinforcement applied. Design considerations based on the algorithms proposed by ACI guidelines are also provided.

  11. Strengthening of a railway bridge with NSMR and CFRP tubes

    DEFF Research Database (Denmark)

    Täljsten, Björn; Bennitz, Anders; Danielsson, Georg

    2008-01-01

    Strengthening of structures with CFRP is today considered an accepted method to upgrade concrete structures. In this paper two different CFRP strengthening systems are combined to give extended service life to a Swedish double-trough-double-track railway bridge, constructed in concrete with a 10 ....... Sensors on bars and tubes display proofs of utilization of the CFRP while displacement sensors and strain gauges on the steel reinforcement due to the small loads in the service limit state show minor effect....

  12. Cytokeratin-positive folliculo-stellate cells in chicken adenohypophysis.

    Science.gov (United States)

    Nishimura, Shotaro; Yamashita, Miyu; Kaneko, Takane; Kawabata, Fuminori; Tabata, Shoji

    2017-11-01

    Folliculo-stellate (FS) cells are non-endocrine cells found in the adenohypophysis and are identified in many animals by the S100 protein marker. Although keratin is another FS marker in several animals, there is no information on localization of keratin in the avian adenohypophysis. In this study, localization of cytokeratin in chicken adenohypophyseal cells was investigated immunohistochemically. Basic cytokeratin (bCK)-positive cells were arranged radially in the cell cords with their cytoplasmic processes reaching the basal lamina. The cell bodies encircled a follicle in the center of the cell cord. Furthermore, the bCK-positive cells were also S100B-positive. Growth hormone, prolactin, adrenocorticotrophic hormone, and luteinizing hormone β-subunit did not co-localize with the bCK-positive cells. In addition, the bCK-positive cells had a laminin-positive area in their cytoplasm. Transmission electron microscopy observed agranular cells equipped with several microvilli that encircled a follicle. These results indicate that bCK-positive cells in the chicken adenohypophysis may be a predominant FS cell population and produce laminin. It is suggested that they function as sustentacular cells to sustain the adjacent endocrine cells and the structure of the cell cords in the chicken adenohypophysis. © 2017 Japanese Society of Animal Science.

  13. Strengthening African Union for African Integration: An African ...

    African Journals Online (AJOL)

    Toshiba

    to secure African continent, speed up development process, and strengthen our survival ... Regional integration generally involves a somewhat complex web of cooperation ... networking of various government institutions to provide and shape.

  14. More Decent Jobs in Peru: Strengthening Research and ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    More Decent Jobs in Peru: Strengthening Research and Policymaking Capacities. Despite ... In turn, such understanding requires appropriate data. Currently ... Call for new OWSD Fellowships for Early Career Women Scientists now open.

  15. Protein-Mediated Interactions of Pancreatic Islet Cells

    Directory of Open Access Journals (Sweden)

    Paolo Meda

    2013-01-01

    Full Text Available The islets of Langerhans collectively form the endocrine pancreas, the organ that is soley responsible for insulin secretion in mammals, and which plays a prominent role in the control of circulating glucose and metabolism. Normal function of these islets implies the coordination of different types of endocrine cells, noticeably of the beta cells which produce insulin. Given that an appropriate secretion of this hormone is vital to the organism, a number of mechanisms have been selected during evolution, which now converge to coordinate beta cell functions. Among these, several mechanisms depend on different families of integral membrane proteins, which ensure direct (cadherins, N-CAM, occludin, and claudins and paracrine communications (pannexins between beta cells, and between these cells and the other islet cell types. Also, other proteins (integrins provide communication of the different islet cell types with the materials that form the islet basal laminae and extracellular matrix. Here, we review what is known about these proteins and their signaling in pancreatic β-cells, with particular emphasis on the signaling provided by Cx36, given that this is the integral membrane protein involved in cell-to-cell communication, which has so far been mostly investigated for effects on beta cell functions.

  16. Carbon Fibre-reinforced Polymer Strengthening and monitoring of the Gröndals Bridge in Sweden

    DEFF Research Database (Denmark)

    Täljsten, Björn; Hejll, A.; James, G.

    2007-01-01

    to be strengthened. The strengthening methods used were CFRP plates at the serviceability limit state and prestressed dywidag stays at the ultimate limit state. The strengthening was carried out during 2002. At the same time monitoring of the bridge commenced, using LVDT crack gauges as well as optical fiber sensors....

  17. Chikungunya virus dissemination from the midgut of Aedes aegypti is associated with temporal basal lamina degradation during bloodmeal digestion.

    Directory of Open Access Journals (Sweden)

    Shengzhang Dong

    2017-09-01

    Full Text Available In the mosquito, the midgut epithelium is the initial tissue to become infected with an arthropod-borne virus (arbovirus that has been acquired from a vertebrate host along with a viremic bloodmeal. Following its replication in midgut epithelial cells, the virus needs to exit the midgut and infect secondary tissues including the salivary glands before it can be transmitted to another vertebrate host. The viral exit mechanism from the midgut, the midgut escape barrier (MEB, is poorly understood although it is an important determinant of mosquito vector competence for arboviruses. Using chikungunya virus (CHIKV as a model in Aedes aegypti, we demonstrate that the basal lamina (BL of the extracellular matrix (ECM surrounding the midgut constitutes a potential barrier for the virus. The BL, predominantly consisting of collagen IV and laminin, becomes permissive during bloodmeal digestion in the midgut lumen. Bloodmeal digestion, BL permissiveness, and CHIKV dissemination are coincident with increased collagenase activity, diminished collagen IV abundance, and BL shredding in the midgut between 24-32 h post-bloodmeal. This indicates that there may be a window-of-opportunity during which the MEB in Ae. aegypti becomes permissive for CHIKV. Matrix metalloproteinases (MMPs are the principal extracellular endopeptidases responsible for the degradation/remodeling of the ECM including the BL. We focused on Ae. aegypti (AeMMP1, which is expressed in midgut epithelial cells, is inducible upon bloodfeeding, and shows collagenase (gelatinase activity. However, attempts to inhibit AeMMP activity in general or specifically that of AeMMP1 did not seem to affect its function nor produce an altered midgut escape phenotype. As an alternative, we silenced and overexpressed the Ae. aegypti tissue inhibitor of metalloproteinases (AeTIMP in the mosquito midgut. AeTIMP was highly upregulated in the midgut during bloodmeal digestion and was able to inhibit MMP activity in

  18. Study on Anti-seismic Strengthening of the Ancient Stone Archway

    Directory of Open Access Journals (Sweden)

    Zhang Ding

    2016-01-01

    Full Text Available Chinese ancient stone archways are in flat structure. And joints of their members are of half tenons and mortises. Under the influence of the earthquake, the resisting ability of archway’s uneven sides is relatively poor and the relevant members have little reliable joints. This paper is to analyze seismic strengthening feasibility of Tiantai mountain stone archway which is damaged from the earthquake and to research on the aspects of the loading mode, structure layout and soundness. On the premise of guaranteeing the authenticity and beauty, we use earthquake damaging mechanism of stone archways and the modern anti-seismic structure designing theory and modern building materials. We also follow the way of the modern construction technology and ancient construction and strengthen the anti-seismic way of the resisting ability of Tiantai mountain stone archway’s uneven sides and joints of tenons and mortises. The best anti-seismic strengthening schemes are put forward as well.

  19. Strengthening industry-research linkage for small scale industrial ...

    African Journals Online (AJOL)

    Strengthening industry-research linkage for small scale industrial development in Ghana - the relevance of scientific and technological information. ... Journal of Applied Science and Technology. Journal Home · ABOUT · Advanced Search ...

  20. Visibility of lamina dura and periodontal space on periapical radiographs and its comparison with cone beam computed tomography

    Directory of Open Access Journals (Sweden)

    Nimish Prakash

    2015-01-01

    Full Text Available Objectives: To retrospectively evaluate the subjective quality of images of cone beam computed tomography and compare with periapical radiographs (PR to determine whether lamina dura (LD and periodontal ligament (PDL space can be detected and reported. Study Design: Sixty scans for anterior and posterior teeth with PR were included and scored on four point subjective scale. Scores assessed using Wilcoxon Signed rank test with the level of statistical significance P < 0.05. Results: Maximum number of ties for LD in anteriors was seen in coronal section (16 and in posteriors with sagittal section (17. Assessing PDL space in anteriors, high number of ties was seen with coronal section (25 and sagittal section (21, while for posteriors showed a high number of ties in all sections. Conclusions: LD could be observed and reported in coronal section for anteriors and in sagittal section for posteriors and PDL space in all the sections for both anteriors and posteriors.

  1. 3D FE Analysis of RC Beams Externally Strengthened with SRG/SRP Systems

    Directory of Open Access Journals (Sweden)

    Francesco Bencardino

    2016-05-01

    Full Text Available The purpose of this study is to evaluate, through a nonlinear Finite Element (FE analysis, the structural behavior of Reinforced Concrete (RC beams externally strengthened by using Steel Reinforced Grout (SRG and Steel Reinforced Polymer (SRP systems. The parameters taken into account were the external strengthening configuration, with or without U-wrap end anchorages, as well as the strengthening materials. The numerical simulations were carried out by using a three-dimensional (3D FE model. The linear and nonlinear behavior of all materials was modeled by appropriate constitutive laws and the connection between concrete substrate and external reinforcing layer was simulated by means of cohesive surfaces with appropriate bond-slip laws. In order to overcome convergence difficulties, to simulate the quasi-static response of the strengthened RC beams, a dynamic approach was adopted. The numerical results in terms of load-displacement curves, failure modes, and load and strain values at critical stages were validated against some experimental data. As a result, the proposed 3D FE model can be used to predict the structural behavior up to ultimate stage of similar strengthened beams without carrying out experimental tests.

  2. West African think tank strengthens outreach and partnerships ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2016-04-28

    Apr 28, 2016 ... ... on organizational strengthening measures to increase its financial autonomy. ... were then put into practice with key financial and technical partners. ... Développement Afrique) is an independent non-profit organization ...

  3. Implementation phase – Strengthening community to health facility ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Home · What we do ... Access to quality sexual and reproductive health information, services, prenatal services, and delivery services is ... should contribute to strengthening and improving the quality of provincial maternal health services.

  4. Strengthening CRTD-A's Organizational and Program Capacity ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ... solid history of collaboration with IDRC at the project level. This grant will help CRTD-A further its strategic research agenda within a Women's Rights and Citizenship framework; to strengthen and rationalize its institutional capacity; and to engage more substantively and advantageously with northern research institutions.

  5. Strengthening political co-operation through multilateral disarmament

    International Nuclear Information System (INIS)

    Ekeus, R.

    1991-01-01

    In this paper, the Ministry for Foreign Affairs of Sweden discussed how the multilateral disarmament concept has contributed and still can contribute to strengthen political co-operation. This approach is the opposite to the usual question on how to achieve multilateral disarmament through political co-operation

  6. Strengthening Community Land Rights and Responses to ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Strengthening Community Land Rights and Responses to Involuntary Displacement Caused by Development Projects in Zimbabwe ... The construction of hydro-electric dams and other large mining and agricultural projects, for example, have led to negative consequences due to weak land tenure rights and a more general ...

  7. Institutional strengthening in Egyptian development aid projects

    NARCIS (Netherlands)

    Walbeek, M.M.; Vlotman, W.F.

    2003-01-01

    In recent years Dutch aid projects have focused more on institutional strengthening. The overall impact of this type of aid has been limited. This paper explores possible reasons for this. In Egypt, it appeared to be difficult to make significant changes in the institutional setting. Main

  8. Long Term Monitoring of Microbial Induced Soil Strengthening Processes

    Science.gov (United States)

    Saneiyan, S.; Ntarlagiannis, D.; Werkema, D. D., Jr.; Colwell, F. S.; Ohan, J.

    2016-12-01

    Soil strengthening/stabilization processes are used to address some of soil quality issues. Microbial induced calcite precipitation (MICP) is a promising soil stabilization process that could offer long term solution by overcoming problems of commonly used methods (e.g. injecting cement slurry). MICP can be applied in larger spatial scales, allowing the enhanced soils to be maintained in an economic sustainable and environmental friendly way. Methods are sought for the long term monitoring of MICP enhanced soils. The spectral induced polarization (SIP) method is one promising method due to sensitivity on such processes and the ability for long term, even autonomous, operation as well as cost effectiveness. Previous laboratory tests showed the sensitivity of the SIP method on soil strengthening as a result of abiotic calcite precipitation. We extended this work to biotic calcite precipitation through MICP. Early results suggest that the MICP formed calcite is denser and could provide improved strengthening capabilities. Our results are supported by geophysical (SIP and shear-wave velocity), geo-chemical and microbiological monitoring. Destructive analysis and visualization (scanning electron imaging - SEM) is expected to provide conclusive evidence on the MICP long term effectiveness.

  9. New deformation model of grain boundary strengthening in polycrystalline metals

    International Nuclear Information System (INIS)

    Trefilov, V.I.; Moiseev, V.F.; Pechkovskij, Eh.P.

    1988-01-01

    A new model explaining grain boundary strengthening in polycrystalline metals and alloys by strain hardening due to localization of plastic deformation in narrow bands near grain boundaries is suggested. Occurrence of localized deformation is caused by different flow stresses in grains of different orientation. A new model takes into account the active role of stress concentrator, independence of the strengthening coefficient on deformation, influence of segregations. Successful use of the model suggested for explanation of rhenium effect in molybdenum and tungsten is alloys pointed out

  10. Deformation Analysis of RC Ties Externally Strengthened with FRP Sheets

    Science.gov (United States)

    Gribniak, V.; Arnautov, A. K.; Kaklauskas, G.; Jakstaite, R.; Tamulenas, V.; Gudonis, E.

    2014-11-01

    The current study has two objectives: to validate the ability of the Atena finite-element software to estimate the deformations of reinforced concrete (RC) elements strengthened with fiber-reinforced polymer (FRP) sheets and to assess the effect of FRP-to-concrete bond strength on the results of numerical simulation. It is shown that the bond strength has to be selected according to the overall stiffness of the composite element. The numerical results found are corroborated experimentally by tensile tests of RC elements strengthened with basalt FRP sheets.

  11. Partial strengthening of R.C square columns using CFRP

    Directory of Open Access Journals (Sweden)

    Ahmed Shaban Abdel-Hay

    2014-12-01

    An experimental program was undertaken testing ten square columns 200 × 200 × 2000 mm. One of them was a control specimen and the other nine specimens were strengthened with CFRP. The main parameters studied in this research were the compressive strength of the upper part, the height of the upper poor concrete part, and the height of CFRP wrapped part of column. The experimental results including mode of failure, ultimate load, concrete strain, and fiber strains were analyzed. The main conclusion of this research was, partial strengthening of square column using CFRP can be permitted and gives good results of the column carrying capacity.

  12. The strengthening effect of percutaneous vertebroplasty

    Energy Technology Data Exchange (ETDEWEB)

    Dean, J.R.; Ison, K.T.; Gishen, P

    2000-06-01

    AIM: To examine whether single-needle vertebroplasty is effective in strengthening vertebrae. MATERIALS AND METHODS: Four adjacent intact lumbar vertebrae were removed from each of nine adult post-mortem subjects. One or two vertebra of each set was injected with low viscosity acrylic bone cement using a single-track posterolateral approach. Vertebral strength was measured during constant rate axial compression. RESULTS: Single-needle injection delivered different quantities of cement (1-8 ml) in an asymmetric distribution. Injected vertebrae were stronger than controls in 10 out of 12 cases (P < 0.01), suggesting that cement injection increases the load needed to cause initial vertebral fracture. Compression was continued past the point of initial failure, to simulate progressive vertebral collapse. Injected specimens were more resistant to deformation than control specimens (P < 0.05), most of which initially deformed with little increase in load. CONCLUSION: Single-track injection of bone cement appeared to strengthen vertebrae against both initial failure and subsequent collapse. The magnitude of strength increase from vertebroplasty was variable, and did not correlate with the volume of cement injected. Further investigation is needed to optimize the technique. Gishen, P. (2000)

  13. Experimental Tests on Steel Plate-to-Plate Splices Bonded by C-FRPS Laminas with and without Wrapping

    Directory of Open Access Journals (Sweden)

    Mario D’Aniello

    2016-02-01

    Full Text Available The results of an experimental investigation carried out on steel splices bonded by (Carbon-Fiber–Reinforced Polymers C-FRPs are presented in this paper. The main aim of the study is to examine the influence of different parameters on the type of failure and on the ductility of splices. Different configurations of the specimens were considered, including butt and lapped joints using different arrangements for end anchorage of the bonded C-FRP laminas, such as (i external bonding; and (ii anchored jacketing with C-FRP sheets transversally wrapped to the longitudinal axis of the joints. The results in terms of failure modes and response curves are described and discussed, highlighting the potentiality of these types of bonded connections for metal structures. In particular, experimental results showed that (i the failure modes exhibited by both butt and lapped wrapped splices were substantially similar; (ii the wrapped anchoring is beneficial in order to achieve large deformations prior to failure, thus allowing a satisfactory ductility, even though a more timely installation process is necessary.

  14. Responsible and Sustainable Tourism : Strengthening Small-Scale ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Responsible and Sustainable Tourism : Strengthening Small-Scale ... to work with the Costa Rican association of small and medium tourism enterprises of the ... as the hub of a network of small service providers operating within the model. ... marketing and outreach, distance learning, and the integration of services that are ...

  15. Hydrocephalus in mice following X-irradiation at early gestational stage. Possibly due to persistent deceleration of cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Aolad, H.M.; Inouye, Minoru; Darmanto, W.; Hayasaka, Shizu; Murata, Yoshiharu [Nagoya Univ. (Japan). Research Inst. of Environmental Medicine

    2000-09-01

    The pathogenesis of X-ray-induced congenital hydrocephalus was studied. Pregnant mice were irradiated at 1.4 Gy on gestational day 7 (G7). Four hours after irradiation, extensive cell death was evident in the neuroepithelium and underlying mesoderm of the head region, and proliferating cell nuclear antigen (PCNA)-immunoreactive cells almost disappeared. Embryos with thinner lamina terminalis of the telecephalon, when compared with that of the control, were found in the irradiated group on G9. As early as G11 in some irradiated embryos the telencephalic wall was thinner and lateral ventricles were larger than those of the control. The choroid invagination from the lamina terminalis began on G11 in the control brain, but not in the affected brain. During the following development, fetuses with readily apparent hydrocephalus were consistently found among irradiated fetuses. In these brains the brain mantle was thinner, the corpus striatum and thalamic regions were smaller, and lateral ventricles were larger than those of the control. Even on G11 and G13 the frequencies of PCNA-positive cells in the brain mantle and other brain regions were lower in the hydrocephalic brain than those of the control, suggesting a decelerated proliferation of successive cell generations following exposure to X-rays. The cerebral aqueduct was open in the hydrocephalic brain during the fetal period when the lateral ventricles were dilated. The head was vaulted after birth but the cerebral aqueduct was not completely occluded even in these animals. These findings suggested that cell death in the neuroepithelium followed by a persistent deceleration of neural cell proliferation, resulting in the hypoplasia of brain parenchyma with compensatory ventricular dilatation, is important for the establishment of hydrocephalus. (author)

  16. Hydrocephalus in mice following X-irradiation at early gestational stage. Possibly due to persistent deceleration of cell proliferation

    International Nuclear Information System (INIS)

    Aolad, H.M.; Inouye, Minoru; Darmanto, W.; Hayasaka, Shizu; Murata, Yoshiharu

    2000-01-01

    The pathogenesis of X-ray-induced congenital hydrocephalus was studied. Pregnant mice were irradiated at 1.4 Gy on gestational day 7 (G7). Four hours after irradiation, extensive cell death was evident in the neuroepithelium and underlying mesoderm of the head region, and proliferating cell nuclear antigen (PCNA)-immunoreactive cells almost disappeared. Embryos with thinner lamina terminalis of the telecephalon, when compared with that of the control, were found in the irradiated group on G9. As early as G11 in some irradiated embryos the telencephalic wall was thinner and lateral ventricles were larger than those of the control. The choroid invagination from the lamina terminalis began on G11 in the control brain, but not in the affected brain. During the following development, fetuses with readily apparent hydrocephalus were consistently found among irradiated fetuses. In these brains the brain mantle was thinner, the corpus striatum and thalamic regions were smaller, and lateral ventricles were larger than those of the control. Even on G11 and G13 the frequencies of PCNA-positive cells in the brain mantle and other brain regions were lower in the hydrocephalic brain than those of the control, suggesting a decelerated proliferation of successive cell generations following exposure to X-rays. The cerebral aqueduct was open in the hydrocephalic brain during the fetal period when the lateral ventricles were dilated. The head was vaulted after birth but the cerebral aqueduct was not completely occluded even in these animals. These findings suggested that cell death in the neuroepithelium followed by a persistent deceleration of neural cell proliferation, resulting in the hypoplasia of brain parenchyma with compensatory ventricular dilatation, is important for the establishment of hydrocephalus. (author)

  17. Constraints to strengthening public sector accountability through civil society: the case of Morocco

    NARCIS (Netherlands)

    S.I. Bergh (Sylvia)

    2009-01-01

    textabstractThis paper discusses the extent to which civil society contributes to strengthening public sector accountability in Morocco. The main argument in this paper is that despite a few recent encouraging examples, civil society’s role in strengthening public sector accountability remains

  18. Muscle-strengthening and conditioning activities and risk of type 2 diabetes

    DEFF Research Database (Denmark)

    Grøntved, Anders; Pan, An; Mekary, Rania A

    2014-01-01

    BACKGROUND: It is well established that aerobic physical activity can lower the risk of type 2 diabetes (T2D), but whether muscle-strengthening activities are beneficial for the prevention of T2D is unclear. This study examined the association of muscle-strengthening activities with the risk of T2D...... at baseline. Participants reported weekly time spent on resistance exercise, lower intensity muscular conditioning exercises (yoga, stretching, toning), and aerobic moderate and vigorous physical activity (MVPA) at baseline and in 2004/2005. Cox regression with adjustment for major determinants for T2D...... include that muscle-strengthening and conditioning activity and other types of physical activity were assessed by a self-administered questionnaire and that the study population consisted of registered nurses with mostly European ancestry. CONCLUSIONS: Our study suggests that engagement in muscle...

  19. The fate of epithelial cells in the human large intestine.

    Science.gov (United States)

    Barkla, D H; Gibson, P R

    1999-08-01

    One hundred and forty biopsies of the colon and rectum, collected during routine colonoscopies of 51 patients aged 19 to 74 years, were examined using light microscopy and transmission and scanning electron microscopy. The results indicated that surface epithelial cells undergo apoptosis, passing through fenestrations in the basement membrane to where they enter the lamina propria and are taken up by macrophages; and it is hypothesized that apoptotic cells are carried through the fenestrations on a current of fluid. The study also found that epithelial cells positioned over the crypts are better attached and more robust than those more distant from the crypt opening; and it is further hypothesized that, after reaching the top of the crypts, some goblet cells cease secreting mucus and pass onto the surface compartment of absorptive cells. An unexpected finding was that the lower regions of the crypts commonly contain isolated necrotic colonocytes. Apoptotic cells were rarely observed in the crypt epithelium. The findings of this study support the "recycling" model of epithelial cell death in the surface compartment of the human colon.

  20. Strengthening of non-seismically detailed reinforced concrete beam ...

    Indian Academy of Sciences (India)

    work and in order to carry the anchorages sufficiently away from the column face ..... Owing to the strengthening application, joint shear stress–strain behaviour was ..... structures (ACI 352R-02), MI: American Concrete Institute, Farmington Hills.

  1. Strengthened International Nuclear Safeguards; burdens and Effects on Nuclear Technology Development

    International Nuclear Information System (INIS)

    Badawy, I.

    2000-01-01

    The present paper deals with the recent direction of strengthening the international nuclear safeguards and the effects on the development of nuclear technology for peaceful applications. The new basic principles for strengthening the international nuclear control in the direction of undeclared nuclear activities are elaborated, and the national obligations are indicated. The burdens on the development of nuclear technology are discussed. Approaches are proposed in this work for coping with the present and future situations

  2. Flexural Strength Of Prestressed Concrete Beams With Openings And Strengthened With CFRP Sheets

    Directory of Open Access Journals (Sweden)

    Dr. Mustafa B. Dawood

    2015-06-01

    Full Text Available Abstract This paper presents an experimental investigation of flexural strength of pretensioned prestressed concrete beams with openings and strengthened with CFRP sheets tested as simply supported span subjected under two-point loading. The experimental work includes testing of nine prestressed concrete beams specimens with dimensions effective length 1800mm depth 300mm width 130mm two of which were without openings as a control beams one without and the other with strengthening by CFRP three were with openings and the remaining four with openings and strengthened with CFRP sheets. The opening was made at square shape 100100 mm in flexure zone at mid span of beam. Several design parameters were varied such as opening width opening depth and strengthening of openings of beams by CFRP sheets at compression and tension zone. Experimental results showed that the presence of square opening with ratio hH 0.333 and rectangular opening with ratio hH from 0.333-0.5 at mid span of beams decreased the ultimate load about 5.5 and 5.5-33.1 respectively when compared with beam without openings control beam. The externally strengthened prestressed concrete beams with bonded CFRP sheets showed a significant increase at the ultimate load this increase was about 10.9-28.8 for flexure beams when compared with the unstrengthened beams. Moreover the load-deflection curves for flexure beams strengthened with CFRP sheets were stiffer than the unstrengthened beams. Therefore this results gave a good indication about using CFRP sheets in improvement of deflection.

  3. Working Together for Children: Strengthening Transition Pathways

    Science.gov (United States)

    Collie, Louise; Willis, Felicity; Paine, Crystal; Windsor, Corina

    2007-01-01

    The "Working Together for Children: Strengthening Transition Pathways" Team has identified that there is a gap between the Early Childhood settings and schools within the Dubbo area. Through meetings with early childhood professionals within Dubbo the authors have identified that the current landscape of care and education within their community…

  4. Full Scale Reinforced Concrete Beam-Column Joints Strengthened with Steel Reinforced Polymer Systems

    Directory of Open Access Journals (Sweden)

    Alessandro De Vita

    2017-07-01

    Full Text Available This paper presents the results of an experimental campaign performed at the Laboratory of Materials and Structural Testing of the University of Salerno (Italy in order to investigate the seismic performance of reinforced concrete (RC beam-column joints strengthened with steel reinforced polymer (SRP systems. With the aim to represent typical façade frames’ beam-column subassemblies found in existing RC buildings, specimens were provided with two short beam stubs orthogonal to the main beam and were designed with inadequate seismic details. Five members were strengthened by using two different SRP layouts while the remaining ones were used as benchmarks. Once damaged, two specimens were also repaired, retrofitted with SRP, and subjected to cyclic test again. The results of cyclic tests performed on SRP strengthened joints are examined through a comparison with the outcomes of the previous experimental program including companion specimens not provided with transverse beam stubs and strengthened by carbon fiber-reinforced polymer (CFRP systems. In particular, both qualitative and quantitative considerations about the influence of the confining effect provided by the secondary beams on the joint response, the suitability of all the adopted strengthening solutions (SRP/CFRP systems, the performances and the failure modes experienced in the several cases studied are provided.

  5. FE Modelling of the Seismic Behavior of Wide Beam-Column Joints Strengthened with CFRP Systems

    Directory of Open Access Journals (Sweden)

    Giuseppe Santarsiero

    2018-02-01

    Full Text Available A large share of reinforced concrete (RC framed buildings is provided with wide beams being a type of beam allowing greater freedom in the architectural arrangement of interiors, beyond further advantage due to fewer formworks needed during the construction. Nevertheless, little attention has been devoted to the seismic vulnerability of this kind of framed RC buildings as well as to the study of strengthening systems purposely developed for wide beams and wide beam-column connections. Under these premises, this paper proposes simple strengthening solutions made by Fibre Reinforced Polymers (FRP systems able to effectively improve seismic capacity through feasible arrangement suitable in case a wide beam is present. On the basis of wide beam-column joints previously tested without strengthening system, detailed nonlinear finite element models were calibrated. Then, an FRP strengthening intervention based on a brand new arrangement was modeled in order to perform additional simulations under seismic actions. This way, the effectiveness of the strengthening intervention was assessed finding out that significant strength and ductility increments were achieved with a relatively simple and cheap strengthening arrangement. Additional research would be desirable in the form of experimental tests on the simulated wide beam-column joints.

  6. A TEM quantitative evaluation of strengthening in an Mg-RE alloy reinforced with SiC

    International Nuclear Information System (INIS)

    Cabibbo, Marcello; Spigarelli, Stefano

    2011-01-01

    Magnesium alloys containing rare earth elements are known to have high specific strength, good creep and corrosion resistance up to 523 K. The addition of SiC ceramic particles strengthens the metal matrix composite resulting in better wear and creep resistance while maintaining good machinability. The role of the reinforcement particles in enhancing strength can be quantitatively evaluated using transmission electron microscopy (TEM). This paper presents a quantitative evaluation of the different strengthening contributions, determined through TEM inspections, in an SiC Mg-RE composite alloy containing yttrium, neodymium, gadolinium and dysprosium. Compression tests at temperatures ranging between 290 and 573 K were carried out. The microstructure strengthening mechanism was studied for all the compression conditions. Strengthening was compared to the mechanical results and the way the different contributions were combined is also discussed and justified. - Research Highlights: → TEM yield strengthening terms evaluation on a Mg-RE SiC alloy. → The evaluation has been extended to different compression temperature conditions. → Linear and Quadratic sum has been proposed and validated. → Hall-Petch was found to be the most prominent strengthening contributions.

  7. The Satellite Cell in Male and Female, Developing and Adult Mouse Muscle: Distinct Stem Cells for Growth and Regeneration

    Science.gov (United States)

    Neal, Alice; Boldrin, Luisa; Morgan, Jennifer Elizabeth

    2012-01-01

    Satellite cells are myogenic cells found between the basal lamina and the sarcolemma of the muscle fibre. Satellite cells are the source of new myofibres; as such, satellite cell transplantation holds promise as a treatment for muscular dystrophies. We have investigated age and sex differences between mouse satellite cells in vitro and assessed the importance of these factors as mediators of donor cell engraftment in an in vivo model of satellite cell transplantation. We found that satellite cell numbers are increased in growing compared to adult and in male compared to female adult mice. We saw no difference in the expression of the myogenic regulatory factors between male and female mice, but distinct profiles were observed according to developmental stage. We show that, in contrast to adult mice, the majority of satellite cells from two week old mice are proliferating to facilitate myofibre growth; however a small proportion of these cells are quiescent and not contributing to this growth programme. Despite observed changes in satellite cell populations, there is no difference in engraftment efficiency either between satellite cells derived from adult or pre-weaned donor mice, male or female donor cells, or between male and female host muscle environments. We suggest there exist two distinct satellite cell populations: one for muscle growth and maintenance and one for muscle regeneration. PMID:22662253

  8. Training in Values to Strengthen Social and Civic Coexistence

    Directory of Open Access Journals (Sweden)

    Yajaira del Valle Cadenas Terán

    2017-02-01

    Full Text Available The purpose of this study is to present significantly values training to strengthen social and citizen considering that the coexistence of human beings has not been entirely easy, but so far they have managed to relate many of their problems with how to relate and interact with the environment, especially with the social environment. This study was conducted with a literature review which is the basis for targeted strengthening coexistence and citizenship therefore falls from a descriptive research training documentary. In conclusion, the importance of the subject since doors for values, dialogues, reflections, quality of life, among others that reflect the actions of teachers based on principles axiological open.

  9. Reusing Recycling Material as Teaching Strategy to Strengthen Environmental Values

    Directory of Open Access Journals (Sweden)

    Yudit Zaida del Carmen Alarcón de Palma

    2017-08-01

    Full Text Available The study was centered interest implement recycling reuse the material as a teaching strategy to strengthen environmental students “Adolfo Moreno” National Basic School Barinitas parish, municipality Bolivar, Barinas state values. School Year 2014 - 2015. The study was based on the paradigm of qualitative research and research in action type. From this point of view, the study focuses on participatory action this mode, it is limited in so-called field layouts. The study its characteristics was fulfilled in the following phases: diagnosis, planning, implementation, evaluation and systematization. Finally, it can be noted that the implementation of teaching strategies reuse recycle material for strengthening environmental students "Adolfo Moreno" National Basic School values; They will be incorporating parents and guardians as well as various educational actors to implement the activities involved in the proposal which seeks to change attitudes to improve through practical actions management standards and conservation practices to achieve an environmental change in institution through technical, theoretical and practical knowledge to strengthen the benefit of recyclables properly handle procedures.

  10. Strengthening capacity to apply health research evidence in policy making: experience from four countries

    Science.gov (United States)

    Hawkes, Sarah; K Aulakh, Bhupinder; Jadeja, Nidhee; Jimenez, Michelle; Buse, Kent; Anwar, Iqbal; Barge, Sandhya; Odubanjo, M Oladoyin; Shukla, Abhay; Ghaffar, Abdul; Whitworth, Jimmy

    2016-01-01

    Increasing the use of evidence in policy making means strengthening capacity on both the supply and demand sides of evidence production. However, little experience of strengthening the capacity of policy makers in low- and middle- income countries has been published to date. We describe the experiences of five projects (in Bangladesh, Gambia, India and Nigeria), where collaborative teams of researchers and policy makers/policy influencers worked to strengthen policy maker capacity to increase the use of evidence in policy. Activities were focused on three (interlinked) levels of capacity building: individual, organizational and, occasionally, institutional. Interventions included increasing access to research/data, promoting frequent interactions between researchers and members of the policy communities, and increasing the receptivity towards research/data in policy making or policy-implementing organizations. Teams were successful in building the capacity of individuals to access, understand and use evidence/data. Strengthening organizational capacity generally involved support to infrastructure (e.g. through information technology resources) and was also deemed to be successful. There was less appetite to address the need to strengthen institutional capacity—although this was acknowledged to be fundamental to promoting sustainable use of evidence, it was also recognized as requiring resources, legitimacy and regulatory support from policy makers. Evaluation across the three spheres of capacity building was made more challenging by the lack of agreed upon evaluation frameworks. In this article, we propose a new framework for assessing the impact of capacity strengthening activities to promote the use of evidence/data in policy making. Our evaluation concluded that strengthening the capacity of individuals and organizations is an important but likely insufficient step in ensuring the use of evidence/data in policy-cycles. Sustainability of evidence

  11. Fine structure of subepithelial "free" and corpuscular trigeminal nerve endings in anterior hard palate of the rat.

    Science.gov (United States)

    Byers, M R; Yeh, Y

    1984-01-01

    Axonally transported protein labeled many trigeminal nerve endings in subepithelial regions of the anterior hard palate of the rat. Sensory endings were most numerous in the lamina propria near the tips of the palatal rugae where large connective tissue and epithelial papillae interdigitated. Two kinds of sensory ending were found there: "free" endings, and a variety of corpuscular endings. The "free" sensory endings consisted of bundles of unmyelinated axons separated from the connective tissue by relatively unspecialized Schwann cells covering part or all of their surface and a completely continuous basal lamina; they were commonly found running parallel to the epithelium or near corpuscular endings. The corpuscular sensory endings all had a specialized nerve form, specialized Schwann cells, and axonal fingers projecting into the corpuscular basal lamina or connective tissue. There were at least four distinct types of corpuscular ending: Ruffini-like endings were found among dense collagen bundles, and they had a flattened nerve ending with a flattened Schwann lamella on either side. Meissner endings had an ordered stack of flattened nerve terminals with flattened Schwann cells and much basal lamina within and around the corpuscle. Simple corpuscles were single nerve endings surrounded by several layers of concentric lamellar Schwann processes. Glomerular endings were found in lamina propria papillae or encircling epithelial papillae; they were a tangle of varied neural forms each of which had apposed flattened Schwann cells, and a layer of basal lamina of varied thickness. Fibroblasts often formed incomplete partitions around Meissner and simple corpuscles. The axoplasm of all kinds of subepithelial sensory endings contained numerous mitochondria and vesicles, as well as occasional multivesicular bodies and lysosomes; the axoplasm of all endings was pale with few microtubules and neurofilaments. The specialized lamellar Schwann cells had much pinocytotic

  12. Strengthening of Unreinforced Masonry Walls with Composite Materials

    Directory of Open Access Journals (Sweden)

    Ioana-Sorina Enţuc

    2004-01-01

    Full Text Available Unreinforced masonry (URM is considered one of the oldest construction materials being until the end of XIXth century, the basic material for: foundations, walls, columns, volts, staircases, floor joints, roofs, retaining walls, drainage channels, barrages, etc. Construction with URM elements posses a series of advantages such as: fire resistance, thermal an acoustic insulations between interior and outside spaces, humidity resistance. However the URM elements have some significant inconveniences such as: large self weight (heaviness causes cracks in the other elements of structures, reduced mechanical strengths in comparison with other traditional materials (steel and concrete, low tenacity, great manual labor consumptions, and vulnerability to earthquakes. Various factors cause deteriorations which must be overcome by strengthening solutions. Some strengthening solutions based on fiber reinforced polymers (FRP products applied directly on URM brick walls are presented in the paper.

  13. How to strengthen customer loyalty, using customer segmentation?

    Directory of Open Access Journals (Sweden)

    MELNIC Elena Lidia

    2017-01-01

    Full Text Available Do you provide exceptional customer service?”, “Is the customer service in your company extraordinary?” “How to convert satis fied customers into loyal customers?” - are the most frequent questions of today’s managers and have driven the research on this article to getting the answer to a highly important marketing topic “How to strengthen customer loyalty using customer segmentation?”. Anyone who has bought a product or a service has probably suffered at least once from a company’s apparent indifference to what should be its first concern: the customer experiences. If this is the case, the company is in a wrong direction, since loyalty is the most powerful tool in today competitive market. To strengthen the bonds with these high-profit customers, innovative companies are deploying enterprise-wide strategies built on consumer segmentation.

  14. Strengthening Social and Emotional Intelligences through Writing

    Science.gov (United States)

    Burth, Jeanne Hager; McConnell, Michelle

    2017-01-01

    Using writing to allow children with Autism Spectrum Disorder (ASD) to express how they are feeling or to stimulate thinking about a social situation will allow the students the opportunity to strengthen social and emotional intelligences. By giving prompts about different social and emotional situations or ideas to children, the teacher allows…

  15. Experimental Investigation for Behavior of Spliced Continuous RC Girders Strengthened with CFRP Laminates

    Directory of Open Access Journals (Sweden)

    Ammar Yasir Ali

    2016-03-01

    Full Text Available In this paper, the behavior of spliced continuous reinforced concrete girders was experimentally investigated. The main objective was to examine the contribution of the carbon fiber reinforced polymer (CFRP laminates in strengthening the spliced continuous reinforced concrete girders. Eight models of continuous reinforced concrete girder were constructed and tested. The test variables were strengthening the splice joints by different schemes of CFRP laminates, presence of horizontal stirrups through the interfaces of the joints and using binder material at the interfaces of the joints. The results showed that strengthening the continuous spliced girders with 45° inclined CFRP laminates led to an increase in the ultimate load in a range of (47 to 74%. Besides, strengthening the continuous spliced girder with horizontal CFRP laminates bonded at its lateral faces could increase the ultimate load by 70%. Additionally, the ultimate load of the continuous spliced girder was increased by (30% due to presence of the horizontal steel stirrups through the interfaces of the joints

  16. Mutual research capacity strengthening: a qualitative study of two-way partnerships in public health research

    Directory of Open Access Journals (Sweden)

    Redman-MacLaren Michelle

    2012-12-01

    Full Text Available Abstract Introduction Capacity building has been employed in international health and development sectors to describe the process of ‘experts’ from more resourced countries training people in less resourced countries. Hence the concept has an implicit power imbalance based on ‘expert’ knowledge. In 2011, a health research strengthening workshop was undertaken at Atoifi Adventist Hospital, Solomon Islands to further strengthen research skills of the Hospital and College of Nursing staff and East Kwaio community leaders through partnering in practical research projects. The workshop was based on participatory research frameworks underpinned by decolonising methodologies, which sought to challenge historical power imbalances and inequities. Our research question was, “Is research capacity strengthening a two-way process?” Methods In this qualitative study, five Solomon Islanders and five Australians each responded to four open-ended questions about their experience of the research capacity strengthening workshop and activities: five chose face to face interview, five chose to provide written responses. Written responses and interview transcripts were inductively analysed in NVivo 9. Results Six major themes emerged. These were: Respectful relationships; Increased knowledge and experience with research process; Participation at all stages in the research process; Contribution to public health action; Support and sustain research opportunities; and Managing challenges of capacity strengthening. All researchers identified benefits for themselves, their institution and/or community, regardless of their role or country of origin, indicating that the capacity strengthening had been a two-way process. Conclusions The flexible and responsive process we used to strengthen research capacity was identified as mutually beneficial. Using community-based participatory frameworks underpinned by decolonising methodologies is assisting to redress

  17. Monolithic Approach to Oxide Dispersion Strengthened Aluminum, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Nassau Stern Company is investigating an approach for manufacturing oxide dispersion strengthened (ODS) aluminum in bulk rather than powder form. The approach...

  18. Strengthening ethical political leadership for sustainable peace and ...

    African Journals Online (AJOL)

    Strengthening ethical political leadership: Uganda as a case study meaningful .... needed are short and long-term strategies for inculcating ethical leadership .... Ethics comprises principles and concepts that guide humans between right ... Virtues of kindness, generosity, hospitality, honesty, compassion, forgiveness, and.

  19. Bond Behavior of Historical Clay Bricks Strengthened with Steel Reinforced Polymers (SRP)

    Science.gov (United States)

    Grande, Ernesto; Imbimbo, Maura; Sacco, Elio

    2011-01-01

    In the strengthening interventions of past and historical masonry constructions, the non-standardized manufacture processes, the ageing and the damage of masonry units, could significantly affect the properties of the surfaces where strengthening materials are applied. This aspect requires particular care in evaluating the performance of externally bonded strengthening layers, especially with reference to the detachment mechanism. The bond response of old masonries could be very different from that occurring in new masonry units which are the ones generally considered in most of the bond tests available in technical literature. The aim of the present paper is the study of the bond behavior of historical clay bricks strengthened with steel reinforced polymers (SRP) materials. In particular, the results of an experimental study concerning new manufactured clay bricks and old bricks extracted from different historical masonry buildings are presented. The obtained results, particularly in terms of bond resistance, detachment mechanism and strain distributions, are discussed for the purpose of analyzing the peculiarities of the historical bricks in comparison with new manufactured ones. Some considerations on the efficacy of the theoretical formulations of the recent Italian code are also carried out. PMID:28880008

  20. Flexural and Shear Behavior of FRP Strengthened AASHTO Type Concrete Bridge Girders

    Directory of Open Access Journals (Sweden)

    Nur Yazdani

    2016-01-01

    Full Text Available Fiber-reinforced polymers (FRP are being increasingly used for the repair and strengthening of deteriorated or unsafe concrete structures, including structurally deficient concrete highway bridges. The behavior of FRP strengthened concrete bridge girders, including failure modes, failure loads, and deflections, can be determined using an analytical finite element modeling approach, as outlined in this paper. The differences in flexural versus shear FRP strengthening and comparison with available design guidelines are also beneficial to design professionals. In this paper, a common AASHTO type prestressed concrete bridge girder with FRP wrapping was analyzed using the ANSYS FEM software and the ACI analytical approach. Both flexural and shear FRP applications, including vertical and inclined shear strengthening, were examined. Results showed that FRP wrapping can significantly benefit concrete bridge girders in terms of flexure/shear capacity increase, deflection reduction, and crack control. The FRP strength was underutilized in the section selected herein, which could be addressed through decrease of the amount of FRP and prestressing steel used, thereby increasing the section ductility. The ACI approach produced comparable results to the FEM and can be effectively and conveniently used in design.

  1. Self-monitoring fiber reinforced polymer strengthening system for civil engineering infrastructures

    Science.gov (United States)

    Jiang, Guoliang; Dawood, Mina; Peters, Kara; Rizkalla, Sami

    2008-03-01

    Fiber reinforced polymer (FRP) materials are currently used for strengthening civil engineering infrastructures. The strengthening system is dependant on the bond characteristics of the FRP to the external surface of the structure to be effective in resisting the applied loads. This paper presents an innovative self-monitoring FRP strengthening system. The system consists of two components which can be embedded in FRP materials to monitor the global and local behavior of the strengthened structure respectively. The first component of the system is designed to evaluate the applied load acting on a structure based on elongation of the FRP layer along the entire span of the structure. Success of the global system has been demonstrated using a full-scale prestressed concrete bridge girder which was loaded up to failure. The test results indicate that this type of sensor can be used to accurately determine the load prior to failure within 15 percent of the measured value. The second sensor component consists of fiber Bragg grating sensors. The sensors were used to monitor the behavior of steel double-lap shear splices tested under tensile loading up to failure. The measurements were used to identify abnormal structural behavior such as epoxy cracking and FRP debonding. Test results were also compared to numerical values obtained from a three dimensional shear-lag model which was developed to predict the sensor response.

  2. Strengthening nuclear security

    International Nuclear Information System (INIS)

    Kurihara, Hiroyoshi

    2003-01-01

    The international situation after the end of the Cold-War has been quite unstable, due to the occurrence of frequent regional conflicts and domestic wars based on ethnic, religious or racial reasons. Further, threats to the would peace and security by non-state actors, like international terrorist groups, have been recognized after 9.11 terrorist attacks to the World Trade Center buildings and to the Pentagon. Utilization of nuclear energy, which encompasses both peaceful uses and military ones, required an establishment of regulatory system, by which risks associated with the development of nuclear energy can be controlled. Accordingly, nuclear safety control system, and then non-proliferation control system has been developed, both in the international level and notional level. In recognition of the present unstable international situations, it is required to establish, maintain and strengthen a system which control nuclear security aspect, in addition to the present systems. (author)

  3. A comparative study on strengthening applications of prefabricated buildings in earthquake regions

    International Nuclear Information System (INIS)

    Arslan, M. Hakan; Gulay, F. Gulten

    2006-01-01

    Damages to prefabricated industrial structures caused by earthquakes in the last ten years in Turkey have occurred to an enormous extent. Among the causes of this damage, the inherent characteristic weakness of the load-carrying systems and constructing most of them according to the earthquake code applied before 1998 can be listed. The tragic situation that appeared after earthquakes emphasized that existing prefabricated constructions should be strengthened/improved according to the code which became valid after 1998. This study comprises three sections. The damage types in prefabricated reinforced concrete structures caused by earthquakes and the strengthening models (samples) that can be applied to these structures will be mentioned in the first and second sections, respectively. The last and the analytical part of the study will be about the selection of the most often damaged industrial construction type which is preferred in industrial regions and application of selecting strengthening methods performed by modeling these structures according to three different span types (1-S, 2-S, 3-S). The strengthening methods will be Sheer wall (SW), Steel Bracing (B), Steel Beam (SB) and Column Jacketing (CJ). All the systems will be calculated by using non-linear procedures (pushover analysis). The analysis performed by using a Software Package (DRAIN-2DX), will be applied to each frame in order to obtain load-displacement curves. The real hinge parameters will be defined using FEMA-356 to reflect the existing conditions. The results will be compared by considering the contribution of strengthening and especially system performance to displacement ductility. (author)

  4. Carbon fiber epoxy composites for both strengthening and health monitoring of structures.

    Science.gov (United States)

    Salvado, Rita; Lopes, Catarina; Szojda, Leszek; Araújo, Pedro; Gorski, Marcin; Velez, Fernando José; Castro-Gomes, João; Krzywon, Rafal

    2015-05-06

    This paper presents a study of the electrical and mechanical behavior of several continuous carbon fibers epoxy composites for both strengthening and monitoring of structures. In these composites, the arrangement of fibers was deliberately diversified to test and understand the ability of the composites for self-sensing low strains. Composites with different arrangements of fibers and textile weaves, mainly unidirectional continuous carbon reinforced composites, were tested at the dynamometer. A two-probe method was considered to measure the relative electrical resistance of these composites during loading. The measured relative electrical resistance includes volume and contact electrical resistances. For all tested specimens, it increases with an increase in tensile strain, at low strain values. This is explained by the improved alignment of fibers and resulting reduction of the number of possible contacts between fibers during loading, increasing as a consequence the contact electrical resistance of the composite. Laboratory tests on strengthening of structural elements were also performed, making hand-made composites by the "wet process", which is commonly used in civil engineering for the strengthening of all types of structures in-situ. Results show that the woven epoxy composite, used for strengthening of concrete elements is also able to sense low deformations, below 1%. Moreover, results clearly show that this textile sensor also improves the mechanical work of the strengthened structural elements, increasing their bearing capacity. Finally, the set of obtained results supports the concept of a textile fabric capable of both structural upgrade and self-monitoring of structures, especially large structures of difficult access and needing constant, sometimes very expensive, health monitoring.

  5. Effective educator-student relationships in nursing education to strengthen nursing students' resilience.

    Science.gov (United States)

    Froneman, Kathleen; Du Plessis, Emmerentia; Koen, Magdelene P

    2016-06-10

    Little research has been conducted in private nursing schools with regard to the educator-student relationship to strengthen the resilience of nursing students and to improve the educator-student relationship. An effective educator-student relationship is a key factor to ensure a positive learning climate where learning can take place and resilience can be strengthened. The purpose was to explore and describe nursing students' view on the basic elements required for an effective educator-student relationship to strengthen their resilience and the educator-student relationship. This study followed an explorative, descriptive and contextual qualitative design in a private nursing education institution in the North West Province. Purposive sampling was used. The sample consisted of 40 enrolled nursing auxiliary students. The World Café Method was used to collect data, which were analysed by means of content analysis. The following five main themes were identified and included: (1) teaching-learning environment, (2) educator-student interaction, (3) educator qualities, (4) staying resilient and (5) strategies to strengthen resilience. Students need a caring and supportive environment; interaction that is constructive, acknowledges human rights and makes use of appropriate non-verbal communication. The educator must display qualities such as love and care, respect, responsibility, morality, patience, being open to new ideas, motivation, willingness to 'go the extra mile' and punctuality. Students reported on various ways how they manage to stay resilient. It thus seems that basic elements required in an effective educator-student relationship to strengthen the resilience of students include the environment, interaction, educator and student's qualities and resilience.

  6. Outcomes following Hip and Quadriceps Strengthening Exercises for Patellofemoral Syndrome: A Systematic Review and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Adebisi Bisi-Balogun

    2015-10-01

    Full Text Available There is growing evidence to support change in the rehabilitation strategy of patellofemoral pain syndrome (PFPS from traditional quadriceps strengthening exercises to inclusion of hip musculature strengthening in individuals with PFPS. Several studies have evaluated effects of quadriceps and hip musculature strengthening on PFPS with varying outcomes on pain and function. This systematic review and meta-analysis aims to synthesize outcomes of pain and function post-intervention and at follow-up to determine whether outcomes vary depending on the exercise strategy in both the short and long term. Electronic databases including MEDLINE, EMBASE, CINAHL, Web of Science, PubMed, Pedro database, Proquest, Science direct, and EBscoHost databases were searched for randomized control trials published between 1st of January 2005 and 31st of June 2015, comparing the outcomes of pain and function following quadriceps strengthening and hip musculature strengthening exercises in patients with PFPS. Two independent reviewers assessed each paper for inclusion and quality. Means and SDs were extracted from each included study to allow effect size calculations and comparison of results. Six randomized control trials met the inclusion criteria. Limited to moderate evidence indicates that hip abductor strengthening was associated with significantly lower pain post-intervention (SMD −0.88, −1.28 to −0.47 95% CI, and at 12 months (SMD −3.10, −3.71 to −2.50 95% CI with large effect sizes (greater than 0.80 compared to quadriceps strengthening. Our findings suggest that incorporating hip musculature strengthening in management of PFPS tailored to individual ability will improve short-term and long-term outcomes of rehabilitation. Further research evaluating the effects of quadriceps and hip abductors strengthening focusing on reduction in anterior knee pain and improvement in function in management of PFPS is needed.

  7. Irradiation performance of oxide dispersion strengthened copper alloys to 150 dpa at 415 degree C

    International Nuclear Information System (INIS)

    Edwards, D.J.; Kumar, A.S.; Anderson, K.R.; Stubbins, J.F.; Garner, F.A.; Hamilton, M.L.

    1991-11-01

    Results have been obtained on the post-irradiation properties of various oxide dispersion strengthened copper alloys irradiated from 34 to 150 dpa at 415 degrees C in the Fast Flux Test Facility. The GlidCop alloys strengthened by Al 2 O 3 continue to outperform other alloys with respect to swelling resistance, and retention of both electrical conductivity and yield strength. Several castable ODS alloys and a Cr 2 O 3 -strengthened alloy show increasingly poor resistance to radiation, especially in their swelling behavior. A HfO 2 -strengthened alloy retains most of its strength and its electrical conductivity reaches a constant level after 50 dpa, but it exhibits a higher residual radioactivity

  8. Influence of exercise and aging on extracellular matrix composition in the skeletal muscle stem cell niche.

    Science.gov (United States)

    Garg, Koyal; Boppart, Marni D

    2016-11-01

    Skeletal muscle is endowed with a remarkable capacity for regeneration, primarily due to the reserve pool of muscle resident satellite cells. The satellite cell is the physiologically quiescent muscle stem cell that resides beneath the basal lamina and adjacent to the sarcolemma. The anatomic location of satellite cells is in close proximity to vasculature where they interact with other muscle resident stem/stromal cells (e.g., mesenchymal stem cells and pericytes) through paracrine mechanisms. This mini-review describes the components of the muscle stem cell niche, as well as the influence of exercise and aging on the muscle stem cell niche. Although exercise promotes ECM reorganization and stem cell accumulation, aging is associated with dense ECM deposition and loss of stem cell function resulting in reduced regenerative capacity and strength. An improved understanding of the niche elements will be valuable to inform the development of therapeutic interventions aimed at improving skeletal muscle regeneration and adaptation over the life span. Copyright © 2016 the American Physiological Society.

  9. Flexural Behavior of RC Slabs Strengthened in Flexure with Basalt Fabric-Reinforced Cementitious Matrix

    Directory of Open Access Journals (Sweden)

    Sugyu Lee

    2018-01-01

    Full Text Available This paper presents both experimental and analytical research results for predicting the flexural capacity of reinforced concrete (RC slabs strengthened in flexure with basalt fabric-reinforced cementitious matrix (FRCM. A total of 13 specimens were fabricated to evaluate the flexural behavior of RC slabs strengthened with basalt FRCM composite and were tested under four-point loading. The fiber type, tensile reinforcement ratio, and the number of fabric layers were chosen as experimental variables. The maximum load of FRCM-strengthened specimens increased from 11.2% to 98.2% relative to the reference specimens. The energy ratio and ductility of the FRCM-strengthened specimens decreased with the higher amount of fabric and tensile reinforcement. The effective stress level of FRCM fabric can be accurately predicted by a bond strength of ACI 549 and Jung’s model.

  10. Strengthening foodborne diseases surveillance in the WHO African ...

    African Journals Online (AJOL)

    The new International Health Regulations (IHR) (2005) cover events of international importance including contaminated food and outbreaks of foodborne disease. The IHR (2005) and other international as well as regional agreements require Member States to strengthen surveillance systems including surveillance for ...

  11. Strengthening 4-H by Analyzing Enrollment Data

    Science.gov (United States)

    Hamilton, Stephen F.; Northern, Angela; Neff, Robert

    2014-01-01

    The study reported here used data from the ACCESS 4-H Enrollment System to gain insight into strengthening New York State's 4-H programming. Member enrollment lists from 2009 to 2012 were analyzed using Microsoft Excel to determine trends and dropout rates. The descriptive data indicate declining 4-H enrollment in recent years and peak enrollment…

  12. Experimental analysis of reinforced concrete columns strengthened with Self-Compacting concrete

    Directory of Open Access Journals (Sweden)

    M. Y. M. Omar

    Full Text Available This paper presents the results of reinforced concrete columns strengthened by addition of a self-compacting concrete overlay at the compressed and at the tensioned face of the member, with and without addition of longitudinal steel bars. Eight columns were submit- ted to loading with an initial eccentricity of 60 mm . These columns had 120 mm x 250 mm of rectangular cross section, 2000 mm in length and four longitudinal reinforcement steel bars with 10 mm in diameter. Reference columns P1 and P2 were tested to failure without any type of rehabilitation. Columns P3 to P8 were loaded to a predefined load (close to the initial yield point of tension reinforce- ment, then unloaded and strengthened for a subsequent test until failure. Results showed that the method of rehabilitation used was effective, increasing the loading capacity of the strengthened pieces by 2 to 5 times the ultimate load of the reference column.

  13. TECHNICAL NOTE: The strengthening effect of guar gum on the yield stress of magnetorheological fluid

    Science.gov (United States)

    Wu, Wei Ping; Zhao, Bin Yuan; Wu, Qing; Chen, LeSheng; Hu, Ke Ao

    2006-08-01

    In this paper we present a novel approach for producing obvious strengthening of the magnetorheological (MR) effect of MR fluids. Carbonyl iron powders coated with guar gum were used as magnetic particles in the MR fluid. Experimental results showed that inducing a guar gum coating not only greatly improved the sedimentation stability but also strengthened the yield stress of the MR fluid. An intermolecular force based model was proposed for explaining the strengthening effect.

  14. Some new characteristics of the strengthening phase in β-phase magnesium-lithium alloys containing aluminum and beryllium

    International Nuclear Information System (INIS)

    Song Guangsheng; Staiger, Mark; Kral, Milo

    2004-01-01

    Hardness, optical-microscopy and X-ray diffraction studies on the strengthening phase in β-phase magnesium-lithium alloys containing different content of aluminum were carried out to give some new characteristics of the strengthening phase affecting lattice distortion and α-Mg precipitation in the β-matrix. In the presence of the strengthening-phase precipitates, the matrix lattice undergoes substantial strain characterized by peak broadening. The peak width in the β-matrix phase pattern can provide an indication of lattice strain caused by the strengthening-phase precipitates. The origin of α-Mg precipitation resulting from the decomposition of the strengthening phase into stable AlLi compound is also explained in the present work

  15. The mammalian neocortical pyramidal cell: a new theory on prenatal development

    Directory of Open Access Journals (Sweden)

    Miguel eMarín-Padilla

    2014-01-01

    Full Text Available Mammals’ new cerebral cortex (neocortex and the new type of pyramidal neuron are mammalian innovations that have evolved for operating their increasing motor capabilities using essentially analogous anatomical and neural makeups. The human neocortex starts to develop in the 6-week-old embryo with the establishment of a primordial cortical organization that resembles the primitive cortices of amphibian and reptiles that operated his early motor activities. From the 8th to the 15th week of age, the new pyramidal neurons, of ependymal origin, are progressively incorporated within this primordial cortex forming a cellular plate that divide its components into those above it (neocortex first lamina and those below it (neocortex subplate elements. From the 16th week of age to birth and postnatally, the new pyramidal neurons continue to elongate functionally their apical dendrite by adding synaptic membrane to incorporate the needed sensory information for operating the animal muscular activities. The new pyramidal neuron’ distinguishing feature is the capacity of elongating anatomically and functionally its apical dendrite (its main receptive surface without losing its original attachment to first lamina or the location of its soma retaining its essential nature. The number of pyramidal cell functional strata established in the motor cortex increases and reflects each mammalian species motor capabilities: the hedgehog needs 2 pyramidal cell functional strata to carry out all its motor activities, the mouse three, cat four, primates 5 and humans 6. The presence of six pyramidal cell functional strata distinguish the human motor cortex from that of others primates. Homo sapiens represent a new evolutionary stage that have transformed his primate brain for operating his unique motor capabilities, such as speaking, writing, painting, sculpturing including thinking as a premotor activity.

  16. Adipose-Derived Mesenchymal Stem Cells in the Regeneration of Vocal Folds: A Study on a Chronic Vocal Fold Scar

    Directory of Open Access Journals (Sweden)

    Angelou Valerie

    2016-01-01

    Full Text Available Background. The aim of the study was to assess the histological effects of autologous infusion of adipose-derived stem cells (ADSC on a chronic vocal fold scar in a rabbit model as compared to an untreated scar as well as in injection of hyaluronic acid. Study Design. Animal experiment. Method. We used 74 New Zealand rabbits. Sixteen of them were used as control/normal group. We created a bilateral vocal fold wound in the remaining 58 rabbits. After 18 months we separated our population into three groups. The first group served as control/scarred group. The second one was injected with hyaluronic acid in the vocal folds, and the third received an autologous adipose-derived stem cell infusion in the scarred vocal folds (ADSC group. We measured the variation of thickness of the lamina propria of the vocal folds and analyzed histopathologic changes in each group after three months. Results. The thickness of the lamina propria was significantly reduced in the group that received the ADSC injection, as compared to the normal/scarred group. The collagen deposition, the hyaluronic acid, the elastin levels, and the organization of elastic fibers tend to return to normal after the injection of ADSC. Conclusions. Autologous injection of adipose-derived stem cells on a vocal fold chronic scar enhanced the healing of the vocal folds and the reduction of the scar tissue, even when compared to other treatments.

  17. Adipose-Derived Mesenchymal Stem Cells in the Regeneration of Vocal Folds: A Study on a Chronic Vocal Fold Scar

    Science.gov (United States)

    Vassiliki, Kalodimou; Irini, Messini; Nikolaos, Psychalakis; Karampela, Eleftheria; Apostolos, Papalois

    2016-01-01

    Background. The aim of the study was to assess the histological effects of autologous infusion of adipose-derived stem cells (ADSC) on a chronic vocal fold scar in a rabbit model as compared to an untreated scar as well as in injection of hyaluronic acid. Study Design. Animal experiment. Method. We used 74 New Zealand rabbits. Sixteen of them were used as control/normal group. We created a bilateral vocal fold wound in the remaining 58 rabbits. After 18 months we separated our population into three groups. The first group served as control/scarred group. The second one was injected with hyaluronic acid in the vocal folds, and the third received an autologous adipose-derived stem cell infusion in the scarred vocal folds (ADSC group). We measured the variation of thickness of the lamina propria of the vocal folds and analyzed histopathologic changes in each group after three months. Results. The thickness of the lamina propria was significantly reduced in the group that received the ADSC injection, as compared to the normal/scarred group. The collagen deposition, the hyaluronic acid, the elastin levels, and the organization of elastic fibers tend to return to normal after the injection of ADSC. Conclusions. Autologous injection of adipose-derived stem cells on a vocal fold chronic scar enhanced the healing of the vocal folds and the reduction of the scar tissue, even when compared to other treatments. PMID:26933440

  18. Fukushima Ministerial Conference Urges Continued Work to Strengthen Nuclear Safety

    International Nuclear Information System (INIS)

    2012-01-01

    Full text: Strengthening nuclear safety is a continuous process that leaves no room for complacency, the Co-Presidents of the Fukushima Ministerial Conference on Nuclear Safety said in a statement today. Koichiro Gemba, Japan's Minister of Foreign Affairs, and Fadillah bin Haji Yusof, Malaysia's Deputy Minister of Science, Technology and Innovation, released the Co-Presidents' Statement at the conclusion of the Conference's Ministerial Plenary, on day one of the three-day event. ''It was stressed that nuclear safety is a prerequisite for the peaceful uses of nuclear energy, that strengthening nuclear safety is a continuous process and that there should be no complacency in safety matters,'' the statement said. The statement recognized progress reported by Japan in the response to the Fukushima Daiichi accident, including the achievement of the present stable status of the nuclear power station and the significant decrease in radioactive releases at the accident site. It stressed the importance of continued transparency in sharing objective information on the progress of decommissioning the plant, remediation and waste management, and encouraged Japan to lead an international effort to obtain data from the damaged reactors. ''The lessons learned from these activities, through their dissemination and related cooperation with the international community, are expected to contribute to enhancing the safety and effectiveness of future decommissioning and remediation activities worldwide,'' it said. The statement emphasized the importance of strengthening the IAEA's central role in international efforts to enhance global nuclear safety, underlining the Agency's Safety Standards and the IAEA Action Plan on Nuclear Safety. It urged IAEA Member States to strengthen efforts to implement the Action Plan fully, including the use of international peer reviews and putting the recommendations of such reviews into practice. It stressed the ''utmost importance of establishing and

  19. Langerhans cell histiocytosis of the urinary bladder in a patient with bladder cancer previously treated with intravesical Bacillus Calmette-Guérin therapy.

    Science.gov (United States)

    Numakura, Satoe; Morikawa, Teppei; Ushiku, Tetsuo; Toyoshima, Toyoaki; Fukayama, Masashi

    2014-02-01

    We report an extremely rare case of Langerhans cell histiocytosis (LCH) of the urinary bladder. A 68-year-old man presented with gross hematuria. Cystoscopy showed multiple papillary tumors in the urinary bladder, and transurethral resection was performed. Pathological diagnosis was high-grade papillary urothelial carcinoma with lamina propria invasion. The patient received six treatments with intravesical Bacillus Calmette-Guérin (BCG) therapy. Seven months after surgery, follow-up cystoscopy showed three elevated lesions in the urinary bladder, two of which were identified histologically as recurrent urothelial carcinoma. Microscopic examination of the lesion at the anterior wall revealed diffuse infiltration of medium to large histiocytoid cells in the lamina propria, many of which had distorted nuclei and nuclear grooves. Dense eosinophilic infiltration was also observed. Immunohistochemically, the histiocytoid cells were diffusely positive for S-100 and CD1a, but negative for cytokeratin AE1/AE3 and melanosome-associated antigen recognized by HMB-45. Based on the histological and immunohistochemical features, we diagnosed the lesion as LCH of the urinary bladder. There was no evidence of recurrence of either bladder cancer or LCH after an 18-month follow-up. To avoid misdiagnosis, urologists and pathologists should be aware that LCH may develop in the urinary bladder after intravesical BCG therapy for bladder cancer. Copyright © 2013 Elsevier GmbH. All rights reserved.

  20. IDRC-GDN: A Strengthened Partnership for Research Capacity ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    IDRC-GDN: A Strengthened Partnership for Research Capacity Building. This project provides core funding to the Global Development Network (GDN) over three years. GDN supports social science researchers in developing and transition countries. Its core mission is to enhance policy-relevant research capacity by ...

  1. Strengthening foodborne disease surveillance in the WHO African

    African Journals Online (AJOL)

    OMS

    2012-06-04

    Jun 4, 2012 ... region including acute aflatoxicosis in Kenya in 2004 and bromide poisoning in ... Global Food Infections Network (GFN), has been supporting countries to strengthen ... The surveillance system uses standard case definitions for classifying .... Figure 4: Participating countries and training sites for foodborne.

  2. PRACTICE POINTS Application of ICT in strengthening health ...

    African Journals Online (AJOL)

    Information Communication Technology (ICT) revolution brought opportunities and challenges to developing countries in their efforts to strengthen the Health Management Information Systems (HMIS). In the wake of globalisation, developing countries have no choice but to take advantage of the opportunities and face the ...

  3. Experimental study on fatigue crack propagation rate of RC beam strengthened with carbon fiber laminate

    Science.gov (United States)

    Huang, Peiyan; Liu, Guangwan; Guo, Xinyan; Huang, Man

    2008-11-01

    The experimental research on fatigue crack propagation rate of reinforced concrete (RC) beams strengthened with carbon fiber laminate (CFL) is carried out by MTS system in this paper. The experimental results show that, the main crack propagation on strengthened beam can be summarized into three phases: 1) fast propagation phase; 2) steady propagation and rest phase; 3) unsteady propagation phase. The phase 2-i.e. steady propagation and rest stage makes up about 95% of fatigue life of the strengthened beam. The propagation rate of the main crack, da/dN, in phase 2 can be described by Paris formula, and the constant C and m can be confirmed by the fatigue crack propagation experiments of the RC beams strengthened with CFL under three-point bending loads.

  4. 75 FR 20717 - Federal Housing Administration: Continuation of FHA Reform; Strengthening Risk Management Through...

    Science.gov (United States)

    2010-04-20

    ... Administration: Continuation of FHA Reform; Strengthening Risk Management Through Responsible FHA-Approved...) that are designed to strengthen FHA by improving its management of risk. This final rule increases the... designed to enhance FHA's risk management functions. The announcement preceded completion of an independent...

  5. 75 FR 23582 - Federal Housing Administration: Continuation of FHA Reform-Strengthening Risk Management Through...

    Science.gov (United States)

    2010-05-04

    ...-AI81 Federal Housing Administration: Continuation of FHA Reform-- Strengthening Risk Management Through... Federal Housing Administration (FHA) that are designed to strengthen FHA by improving its management of risk. Although the preamble to the final rule correctly provides that the revised net worth...

  6. Impact Evaluation Study for Institution Strengthening of Social Food Distribution

    Directory of Open Access Journals (Sweden)

    Budiman Notoatmojo

    2016-03-01

    Full Text Available The general objectives of this study were to evaluate whether the implementation of activities for strengthening LDPM could achieve the expected goals, to evaluate whether the LDPM strengthening activities had a positive impact. The study analysis used was descriptive, comparison, and financial analysis. The results of this study have shown that LDPM farmers’ income have increased significantly, and the Gapoktan as LPDM farmers’ institution has been significantly developing as a Bulog function in procuring grain paddy from farmers during peak harvest and distributing rice to stabilize the price of rice during the limited rice in the market.

  7. Food insecurity among students living with HIV: Strengthening safety ...

    African Journals Online (AJOL)

    Food insecurity among students living with HIV: Strengthening safety nets at the Nelson Mandela Metropolitan University, South Africa. ... of age and managed as part of the Campus Health Service antiretroviral therapy (ART) programme.

  8. Impact of a quality improvement project to strengthen infection ...

    African Journals Online (AJOL)

    Impact of a quality improvement project to strengthen infection prevention and control training at rural healthcare facilities. ... African Journal of Health Professions Education. Journal Home · ABOUT THIS JOURNAL · Advanced Search ...

  9. Strengthening regional safeguards

    International Nuclear Information System (INIS)

    Palhares, L.; Almeida, G.; Mafra, O.

    1996-01-01

    Nuclear cooperation between Argentina and Brazil has been growing since the early 1980's and as it grew, so did cooperation with the US Department of Energy (DOE). The Brazilian-Argentine Agency for Accounting and Control of Nuclear Materials (ABACC) was formed in December 1991 to operate the Common System of Accounting and Control of Nuclear Materials (SCCC). In April 1994, ABACC and the DOE signed an Agreement of Cooperation in nuclear material safeguards. This cooperation has included training safeguards inspectors, exchanging nuclear material measurement and containment and surveillance technology, characterizing reference materials, and studying enrichment plant safeguards. The goal of the collaboration is to exchange technology, evaluate new technology in Latin American nuclear facilities, and strengthen regional safeguards. This paper describes the history of the cooperation, its recent activities, and future projects. The cooperation is strongly supported by all three governments: the Republics of Argentina and Brazil and the United States

  10. Laminae development in opal-A precipitates associated with seasonal growth of the form-genus Calothrix (Cyanobacteria), Rehai geothermal area, Tengchong, Yunnan Province, China

    Science.gov (United States)

    Jones, Brian; Peng, Xiaotong

    2015-04-01

    The western discharge apron at Meinuquan (Rehai geothermal area, Yunnan Province, China), which incorporates the upper terrace, terrace front, and lower terrace, is covered with laminated opal-A precipitates that have formed from the spring waters that flow across its surface. Laminae are formed of silicified Calothrix mats or featureless opal-A that contains no microbes, scattered spherical and rod-shaped microbes, and/or rare Calothrix. Rapid silicification of the Calothrix led to preservation of their basal heterocysts, vegetative cells, trichomes, tapering filaments, and laminated and splayed sheaths. The Calothrix mats grew during the dry season when there was maximum sunlight because of low cloud cover. During this time, the mats grew under stable conditions because the water that flowed across the discharge apron was sourced from the springs, and temperature and water geochemistry was more or less constant. Growth of the Calothrix mats decreased during the wet season (April to late September) when sunlight is reduced due to the extensive cloud cover associated with the monsoonal rains. During the wet season, water flowing over the discharge apron is a mixture of rainwater, runoff from the surrounding hillsides, and spring water. Such variable flow conditions, water temperatures, and water geochemistry curtailed microbe growth and impacted silica precipitation. The precipitates at Meinuquan are like those associated with some Icelandic hot springs. Although growth of Calothrix is controlled by sunlight in both settings, the periods of maximum sunlight in China (October-March) and Iceland (June-August) are at different times of the year because of their geographic locations.

  11. Titanium oxide dispersion-strengthened ferritic alloys

    International Nuclear Information System (INIS)

    Hendrix, W.; Vandermeulen, W.

    1980-04-01

    The available data on the DT02 and DT3911 ferritic dispersion strengthened alloys, developed at SCK/CEN, Mol, Belgium, are presented. Both alloys consist of Fe - 13% Cr - 1.5% Mo to which 2% TiO 2 and about 3.5% Ti are added (wt.%). Their main use is for the fabrication of fast breeder reactor cladding tubes but their application as turbine blade material is also envisaged for cases where high damping is important. (auth.)

  12. Carbon Fiber Epoxy Composites for Both Strengthening and Health Monitoring of Structures

    Directory of Open Access Journals (Sweden)

    Rita Salvado

    2015-05-01

    Full Text Available This paper presents a study of the electrical and mechanical behavior of several continuous carbon fibers epoxy composites for both strengthening and monitoring of structures. In these composites, the arrangement of fibers was deliberately diversified to test and understand the ability of the composites for self-sensing low strains. Composites with different arrangements of fibers and textile weaves, mainly unidirectional continuous carbon reinforced composites, were tested at the dynamometer. A two-probe method was considered to measure the relative electrical resistance of these composites during loading. The measured relative electrical resistance includes volume and contact electrical resistances. For all tested specimens, it increases with an increase in tensile strain, at low strain values. This is explained by the improved alignment of fibers and resulting reduction of the number of possible contacts between fibers during loading, increasing as a consequence the contact electrical resistance of the composite. Laboratory tests on strengthening of structural elements were also performed, making hand-made composites by the “wet process”, which is commonly used in civil engineering for the strengthening of all types of structures in-situ. Results show that the woven epoxy composite, used for strengthening of concrete elements is also able to sense low deformations, below 1%. Moreover, results clearly show that this textile sensor also improves the mechanical work of the strengthened structural elements, increasing their bearing capacity. Finally, the set of obtained results supports the concept of a textile fabric capable of both structural upgrade and self-monitoring of structures, especially large structures of difficult access and needing constant, sometimes very expensive, health monitoring.

  13. Why the Australian Monsoon Strengthened During the Cold Last Glacial Maximum?

    Science.gov (United States)

    Yan, M.; Wang, B.; Liu, J.; Ning, L.

    2017-12-01

    The multi-model ensemble simulation suggests that the global monsoon and most sub-monsoons are weakened during the Last Glacial Maximum (LGM) due to the lower green-house gases concentration, the presence of the ice-sheets and the weakened seasonal distribution of insolation. In contrast, the Australian monsoon is strengthened during the LGM. The precipitation there increases in austral summer and decreases in austral winter, so that the annual range or monsoonality increases. The strengthened monsoonality is mainly due to the decreased precipitation in austral winter, which is primarily caused by circulation changes, although the reduced atmospheric water vapor also has a moderate contribution. On the other hand, the strengthened Australian summer monsoon rainfall is likely caused by the change of land-sea thermal contrast due to the alteration of land-sea configuration and by the asymmetric change in sea surface temperature (SST) over Indo-Pacific warm pool region. The strengthened land-sea thermal contrast and Western Pacific-Eastern Indian Ocean thermal gradients in the pre-summer monsoon season triggers a cyclonic wind anomaly that is maintained to the monsoon season, thereby increasing summer precipitation. The increased summer precipitation is associated with the increased cloud cover over the land and decreased cloud cover over the ocean. This may weaken the land-sea thermal contrast, which agrees with the paleoclimate reconstruction. The biases between different models are likely related to the different responses of SST over the North Atlantic Ocean in the pre-summer monsoon season.

  14. Effects of CFRP Strengthening on Dynamic and Fatigue Responses of Composite Bridge

    Directory of Open Access Journals (Sweden)

    Kittisak Kuntiyawichai

    2014-01-01

    Full Text Available This paper investigates the effect of CFRP strengthening on dynamic and fatigue responses of composite bridge using finite element program ABAQUS. Dynamic and fatigue responses of composite bridge due to truck load based on AASHTO standard are investigated. Two types of CFRP strengthening techniques, CFRP sheets and CFRP deck, are applied to both the damaged and undamaged bridges. For the case of damaged bridge, two through-thickness crack sizes, 3 mm and 6 mm in depth, are assumed at midspan of the steel girders. Furthermore, effects of the number of steel girders on the dynamic and fatigue responses are also considered. The results show that the maximum responses of composite bridges occur for dual lane cases. By using CFRP as a strengthening material, the maximum stress and deflection of the steel girders reduce and consequently increase the fatigue life of the girders. After introducing initial crack into the steel girders of the composite bridges, the fatigue life of the bridges is dramatically reduced. However, the overall performance of the damaged composite bridge can be improved by using CFRP, albeit with less effectiveness. Therefore, if cracks are found, steel welding must be performed before strengthening the composite bridge by CFRP.

  15. RC Beams Strengthened with Mechanically Fastened Composites: Experimental Results and Numerical Modeling

    Directory of Open Access Journals (Sweden)

    Enzo Martinelli

    2014-03-01

    Full Text Available The use of mechanically-fastened fiber-reinforced polymer (MF-FRP systems has recently emerged as a competitive solution for the flexural strengthening of reinforced concrete (RC beams and slabs. An overview of the experimental research has proven the effectiveness and the potentiality of the MF-FRP technique which is particularly suitable for emergency repairs or when the speed of installation and immediacy of use are imperative. A finite-element (FE model has been recently developed by the authors with the aim to simulate the behavior of RC beams strengthened in bending by MF-FRP laminates; such a model has also been validated by using a wide experimental database collected from the literature. By following the previous study, the FE model and the assembled database are considered herein with the aim of better exploring the influence of some specific aspects on the structural response of MF-FRP strengthened members, such as the bearing stress-slip relationship assumed for the FRP-concrete interface, the stress-strain law considered for reinforcing steel rebars and the cracking process in RC members resulting in the well-known tension stiffening effect. The considerations drawn from this study will be useful to researchers for the calibration of criteria and design rules for strengthening RC beams through MF-FRP laminates.

  16. Semiempirical Methodology for Estimating the Service Life of Concrete Deck Panels Strengthened with Fiber-Reinforced Polymer

    Directory of Open Access Journals (Sweden)

    Eon-Kyoung Kim

    2014-01-01

    Full Text Available Deterioration of concrete bridge decks affects their durability, safety, and function. It is therefore necessary to conduct structural rehabilitation of damaged concrete decks by strengthening them with fiber-reinforced polymer. Of the recent studies on the strengthened structures, most have focused on static behavior; only a few studies have investigated fatigue behavior. Accurate analysis of fatigue in concrete deck performance requires a more realistic simulated moving load. This study developed a theoretical live-load model to reflect the effect of moving vehicle loads, based on a statistical approach to the measurement of real traffic loads over various time periods in Korea. It assessed the fatigue life and strengthening effect of bridge decks strengthened with either carbon fiber sheets or grid carbon fiber polymer plastic using probabilistic and reliability analyses. It used extrapolations and simulations to derive maximum load effects for time periods ranging from 1 day to 75 years. Limited fatigue tests were conducted and probabilistic and reliability analyses were carried out on the strengthened concrete bridge deck specimens to predict the extended fatigue life. Analysis results indicated that strengthened concrete decks provide sufficient resistance against increasing truck loads during the service life of a bridge.

  17. National viewpoints: Views on strengthened safeguards from Australia, Cuba and South Africa

    International Nuclear Information System (INIS)

    Biggs, I.; Saburido, E.F.; Mxakato-Diseko, N.J.

    1999-01-01

    This paper presents views of Australia, Cuba and South Africa concerned with strengthened safeguards regime. Australia has been involved with the IAEA safeguards system since the first plenary meeting of the Conference on the IAEA Statute in 1956, joined the NPT in 1973 and began concluding bilateral safeguards agreements in 1977. Australia has the greatest respect for the IAEA coordinated efforts started in 1998 to strengthen and integrate the safeguards system. Cuba has always attached special importance to nuclear safeguards activities, recognizing their high priority as well as the important role they have in respect to international disarmament and security. South Africa supports the efforts in strengthening the safeguards activities and remains hopeful that the international community will address the challenges posed by the Trilateral Initiative between Russian federation, USA and IAEA in a mature and cooperative way

  18. [eHealth in Peru: implementation of policies to strengthen health information systems].

    Science.gov (United States)

    Curioso, Walter H

    2014-01-01

    Health information systems play a key role in enabling high quality, complete health information to be available in a timely fashion for operational and strategic decision-making that makes it possible to save lives and improve the health and quality of life of the population. In many countries, health information systems are weak, incomplete, and fragmented. However, there is broad consensus in the literature of the need to strengthen health information systems in countries around the world. The objective of this paper is to present the essential components of the conceptual framework to strengthen health information systems in Peru. It describes the principal actions and strategies of the Ministry of Health of Peru during the process of strengthening health information systems. These systems make it possible to orient policies for appropriate decision-making in public health.

  19. Flexural strengthening of Reinforced Concrete (RC) Beams Retrofitted with Corrugated Glass Fiber Reinforced Polymer (GFRP) Laminates

    Science.gov (United States)

    Aravind, N.; Samanta, Amiya K.; Roy, Dilip Kr. Singha; Thanikal, Joseph V.

    2015-01-01

    Strengthening the structural members of old buildings using advanced materials is a contemporary research in the field of repairs and rehabilitation. Many researchers used plain Glass Fiber Reinforced Polymer (GFRP) sheets for strengthening Reinforced Concrete (RC) beams. In this research work, rectangular corrugated GFRP laminates were used for strengthening RC beams to achieve higher flexural strength and load carrying capacity. Type and dimensions of corrugated profile were selected based on preliminary study using ANSYS software. A total of twenty one beams were tested to study the load carrying capacity of control specimens and beams strengthened with plain sheets and corrugated laminates using epoxy resin. This paper presents the experimental and theoretical study on flexural strengthening of Reinforced Concrete (RC) beams using corrugated GFRP laminates and the results are compared. Mathematical models were developed based on the experimental data and then the models were validated.

  20. Estimate of compressive strength of an unidirectional composite lamina using cross-ply and angle-ply laminates

    Directory of Open Access Journals (Sweden)

    M. Scafè

    2014-07-01

    Full Text Available In this work has been estimated the compressive strength of a unidirectional lamina of a carbon/epoxy composite material, using the cross-ply and angle-ply laminates. Over the years various methods have been developed to deduce compressive properties of composite materials reinforced with long fibres. Each of these methods is characterized by a specific way of applying load to the specimen. The method chosen to perform the compression tests is the Wyoming Combined Loading Compression (CLC Test Method, described in ASTM D 6641 / D 6641M-09. This method presents many advantages, especially: the load application on the specimen (end load combined with shear load, the reproducibility of measurements and the experimental equipment quite simplified. Six different laminates were tested in compressive tests. They were realized by the same unidirectional prepreg, but with different stacking sequences: two cross-ply [0/90]ns, two angle-ply [0/90/±45]ns and two unidirectional laminates [0]ns and [90]ns. The estimate of the compressive strength of the unidirectional laminates at 0°, was done by an indirect analytical method, developed from the classical lamination theory, and which uses a multiplicative parameter known as Back-out Factor (BF. The BF is determined by using the experimental values obtained from compression tests.

  1. Strengthening Africa's science granting councils as champions of ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    The capacity strengthening approach will be a participatory one involving customized regional training courses, on-site coaching for individual councils, peer-to-peer learning among councils, and knowledge exchange during annual learning forums. Implementation of this project is expected to contribute to the goals of the ...

  2. In-Plane Strengthening Effect of Prefabricated Concrete Walls on Masonry Structures: Shaking Table Test

    Directory of Open Access Journals (Sweden)

    Weiwei Li

    2017-01-01

    Full Text Available The improvement effect of a new strengthening strategy on dynamic action of masonry structure, by installing prefabricated concrete walls on the outer facades, is validated by shaking table test presented in this paper. We carried out dynamic tests of two geometrically identical five-story reduced scaled models, including an unstrengthened and a strengthened masonry model. The experimental analysis encompasses seismic performances such as cracking patterns, failure mechanisms, amplification factors of acceleration, and displacements. The results show that the strengthened masonry structure shows much more excellent seismic capacity when compared with the unstrengthened one.

  3. Tight coupling between nucleus and cell migration through the perinuclear actin cap

    Science.gov (United States)

    Kim, Dong-Hwee; Cho, Sangkyun; Wirtz, Denis

    2014-01-01

    ABSTRACT Although eukaryotic cells are known to alternate between ‘advancing’ episodes of fast and persistent movement and ‘hesitation’ episodes of low speed and low persistence, the molecular mechanism that controls the dynamic changes in morphology, speed and persistence of eukaryotic migratory cells remains unclear. Here, we show that the movement of the interphase nucleus during random cell migration switches intermittently between two distinct modes – rotation and translocation – that follow with high fidelity the sequential rounded and elongated morphologies of the nucleus and cell body, respectively. Nuclear rotation and translocation mediate the stop-and-go motion of the cell through the dynamic formation and dissolution, respectively, of the contractile perinuclear actin cap, which is dynamically coupled to the nuclear lamina and the nuclear envelope through LINC complexes. A persistent cell movement and nuclear translocation driven by the actin cap are halted following the disruption of the actin cap, which in turn allows the cell to repolarize for its next persistent move owing to nuclear rotation mediated by cytoplasmic dynein light intermediate chain 2. PMID:24639463

  4. Analysis of Strengthening Mechanisms in an Artificially Aged Ultrafine Grain 6061 Aluminum Alloy

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Rezaei

    2017-12-01

    Full Text Available The current study adopted a quantitative approach to investigating the mechanical properties, and their relationship to the microstructural features, of precipitation-strengthened 6061 aluminum alloy processed through accumulative roll bonding (ARB and aging heat treatment.  To serve this purpose, the contributions of different strengthening mechanisms including grain refinement, precipitation, dislocation and solid-solution strengthening to the yield strength of five-cycle ARB samples processed under pre-aged (ARBed and aged (ARBed+Aged conditions were examined and compared. Microstructural characterizations were performed on the samples through the transmission electron microscope (TEM and X-ray diffraction (XRD. Also, the mechanical properties of the samples were investigated through the tensile test. The obtained results showed that an equiaxed ultrafine grain structure with nano-sized precipitates was created in the both ARBed and ARBed+Aged samples. The grain refinement was the predominant strengthening mechanism which was estimated to contribute 151 and 226 MPa to the ARBed and ARBed+Aged samples, respectively, while the dislocation and Orowan strengthening mechanisms were ranked second with regard to their contributions to the ARBed and ARBed+Aged samples, respectively. The overall yield strength, calculated through the root mean square summation method, was found to be in good agreement with the experimentally determined yield strength. It was also found that the presence of non-shearable precipitates, which interfered with the movement of the dislocations, would be effective for the simultaneous improvement of the strength and ductility of the ARBed+Agedsample .

  5. Behavior of partially defected R.C columns strengthened using steel jackets

    Directory of Open Access Journals (Sweden)

    Ahmed Shaban Abdel-Hay

    2015-08-01

    The main parameters studied were the type of steel jacket used and height of partial strengthened part of column. One of the tested specimens was a control specimen and the other six were partially strengthened with different types of steel jackets such as using 4 steel angles at corners connected with straps, using external ties with different spacings, and using 4 steel plates with different thicknesses welded together and connected to column by anchor bolts. Finally, the experimental results were analyzed and compared with results obtained from finite element analysis using ANSYS program.

  6. Influence of ties on the behavior of short reinforced concrete columns strengthened by external CFRP

    Directory of Open Access Journals (Sweden)

    Sarsam Kaiss

    2018-01-01

    Full Text Available An experimental study was carried out to investigate the behavior of normal strength reinforce concret (RC circular short column strengthned with “carbon fiber reinforced polymer (CFRP sheets”. Three series comprising totally of (15 specimens loaded until failure under concentric compresion load. Strengthening was varied by changing the number of CFRP strips, spacing and wrapping methods. The findings of this research can be summarized as follows: for the columns without CFRP, the influence of the tie spacing was significant: compared with 130 mm tie spacing, dropping the spacing to 100 mm and 70 mm increased the load carrying capacity by 18% and 26%, respectively. The columns with less internal confinement (lesser amount of ties were strengthened more significantly by the CFRP than the ones with greater amount of internal ties. As an example of the varying effectiveness of the fully wrapped CFRP, the column with ties at 130 mm was strengthened by 90% with the CFRP. In contrast, the ones with 70 mm spaced ties only increased in strength with CFRP by 66%. Compared with the control specimen (no CFRP, the same amount of CFRP when used as hoop strips led to more strengthening than using CFRP as a spiral strip- the former led to nearly 9% more strengthening than the latter in the case of 130 mm spaced internal steel ties. In the case of 100 mm internal steel ties, the difference (between the hoops & spiral CFRP strengthening is close to 4%. In contrast, there is no difference between the two methods of strengthening in the heavily tied columns (70 mm tied spacing.

  7. Securing Chinese nuclear power development: further strengthening nuclear security

    International Nuclear Information System (INIS)

    Zhang Hui

    2014-01-01

    Chinese President Xi Jinping addresses China's new concept of nuclear security with four 'equal emphasis' at the third Nuclear Security Summit, and makes four commitments to strengthen nuclear security in the future. To convert President Xi's political commitments into practical, sustainable reality, China should take further steps to install a complete, reliable, and effective security system to ensure that all its nuclear materials and nuclear facilities are effectively protected against the full spectrum of plausible terrorist and criminal threats. This paper suggests the following measures be taken to improve China's existing nuclear security system, including updating and clarifying the requirements for a national level DBT; updating and enforcing existing regulations; further promoting nuclear security culture; balancing the costs of nuclear security, and further strengthening international cooperation on nuclear security. (author)

  8. Myoepithelial Cells: Their Origin and Function in Lacrimal Gland Morphogenesis, Homeostasis, and Repair.

    Science.gov (United States)

    Makarenkova, Helen P; Dartt, Darlene A

    2015-09-01

    Lacrimal gland (LG) is an exocrine tubuloacinar gland that secretes the aqueous layer of the tear film. LG epithelium is composed of ductal, acinar, and myoepithelial cells (MECs) bordering the basal lamina and separating the epithelial layer from the extracellular matrix. Mature MECs have contractile ability and morphologically resemble smooth muscle cells; however, they exhibit features typical for epithelial cells, such as the presence of specific cytokeratin filaments. Increasing evidence supports the assertion that myoepithelial cells (MECs) play key roles in the lacrimal gland development, homeostasis, and stabilizing the normal structure and polarity of LG secretory acini. MECs take part in the formation of extracellular matrix gland and participate in signal exchange between epithelium and stroma. MECs have a high level of plasticity and are able to differentiate into several cell lineages. Here, we provide a review on some of the MEC characteristics and their role in LG morphogenesis, maintenance, and repair.

  9. Strengthening the role of Community Health Representatives in the Navajo Nation

    Directory of Open Access Journals (Sweden)

    Caroline King

    2017-04-01

    Full Text Available Abstract Background Strengthening Community Health Worker systems has been recognized to improve access to chronic disease prevention and management efforts in low-resource communities. The Community Outreach and Patient Empowerment (COPE Program is a Native non-profit organization with formal partnerships with both the Navajo Nation Community Health Representative (CHR Program and the clinical facilities serving the Navajo Nation. COPE works to better integrate CHRs into the local health care system through training, strengthening care coordination, and a standardized culturally appropriate suite of health promotion materials for CHRs to deliver to high-risk individuals in their homes. Methods The objective of this mixed methods, cross sectional evaluation of a longitudinal cohort study was to explore how the COPE Program has effected CHR teams over the past 6 years. COPE staff surveyed CHRs in concurrent years (2014 and 2015 about their perceptions of and experience working with COPE, including potential effects COPE may have had on communication among patients, CHRs, and hospital-based providers. COPE staff also conducted focus groups with all eight Navajo Nation CHR teams. Results CHRs and other stakeholders who viewed our results agree that COPE has improved clinic-community linkages, primarily through strengthened collaborations between Public Health Nurses and CHRs, and access to the Electronic Health Records. CHRs perceived that COPE’s programmatic support has strengthened their validity and reputation with providers and clients, and has enhanced their ability to positively effect health outcomes among their clients. CHRs report an improved ability to deliver health coaching to their clients. Survey results show that 80.2% of CHRs feel strongly positive that COPE trainings are useful, while 44.6% of CHRs felt that communication and teamwork had improved because of COPE. Conclusions These findings suggest that CHRs have experienced

  10. Publisher Correction: Single-cell analysis of experience-dependent transcriptomic states in the mouse visual cortex.

    Science.gov (United States)

    Hrvatin, Sinisa; Hochbaum, Daniel R; Nagy, M Aurel; Cicconet, Marcelo; Robertson, Keiramarie; Cheadle, Lucas; Zilionis, Rapolas; Ratner, Alex; Borges-Monroy, Rebeca; Klein, Allon M; Sabatini, Bernardo L; Greenberg, Michael E

    2018-05-11

    In the version of this article initially published, the x-axis labels in Fig. 3c read Vglut, Gad1/2, Aldh1l1 and Pecam1; they should have read Vglut + , Gad1/2 + , Aldh1l1 + and Pecam1 + . In Fig. 4, the range values were missing from the color scales; they are, from left to right, 4-15, 0-15, 4-15 and 0-15 in Fig. 4a and 4-15, 4-15 and 4-8 in Fig. 4h. In the third paragraph of the main text, the phrase reading "Previous approaches have analyzed a limited number of inhibitory cell types, thus masking the full diversity of excitatory populations" should have read "Previous approaches have analyzed a limited number of inhibitory cell types and masked the full diversity of excitatory populations." In the second paragraph of Results section "Diversity of experience-regulated ERGs," the phrase reading "thus suggesting considerable divergence within the gene expression program responding to early stimuli" should have read "thus suggesting considerable divergence within the early stimulus-responsive gene expression program." In the fourth paragraph of Results section "Excitatory neuronal LRGs," the sentence reading "The anatomical organization of these cell types into sublayers, coupled with divergent transcriptional responses to a sensory stimulus, suggested previously unappreciated functional subdivisions located within the laminae of the mouse visual cortex and resembling the cytoarchitecture in higher mammals" should have read "The anatomical organization of these cell types into sublayers, coupled with divergent transcriptional responses to a sensory stimulus, suggests previously unappreciated functional subdivisions located within the laminae of the mouse visual cortex, resembling the cytoarchitecture in higher mammals." In the last sentence of the Results, "sensory-responsive genes" should have read "sensory-stimulus-responsive genes." The errors have been corrected in the HTML and PDF versions of the article.

  11. Effects of Zr Addition on Strengthening Mechanisms of Al-Alloyed High-Cr ODS Steels.

    Science.gov (United States)

    Ren, Jian; Yu, Liming; Liu, Yongchang; Liu, Chenxi; Li, Huijun; Wu, Jiefeng

    2018-01-12

    Oxide dispersion strengthened (ODS) steels with different contents of zirconium (denoted as 16Cr ODS, 16Cr-0.3Zr ODS and 16Cr-0.6Zr ODS) were fabricated to investigate the effects of Zr on strengthening mechanism of Al-alloyed 16Cr ODS steel. Electron backscatter diffraction (EBSD) results show that the mean grain size of ODS steels could be decreased by Zr addition. Transmission electron microscope (TEM) results indicate that Zr addition could increase the number density but decrease the mean diameter and inter-particle spacing of oxide particles. Furthermore, it is also found that in addition to Y-Al-O nanoparticles, Y-Zr-O oxides with finer size were observed in 16Cr-0.3Zr ODS and 16Cr-0.6Zr ODS steels. These changes in microstructure significantly increase the yield strength (YS) and ultimate tensile strength (UTS) of ODS steels through mechanisms of grain boundary strengthening and dispersion strengthening.

  12. The Ottawa panel clinical practice guidelines for the management of knee osteoarthritis. Part two: strengthening exercise programs.

    Science.gov (United States)

    Brosseau, Lucie; Taki, Jade; Desjardins, Brigit; Thevenot, Odette; Fransen, Marlene; Wells, George A; Mizusaki Imoto, Aline; Toupin-April, Karine; Westby, Marie; Álvarez Gallardo, Inmaculada C; Gifford, Wendy; Laferrière, Lucie; Rahman, Prinon; Loew, Laurianne; De Angelis, Gino; Cavallo, Sabrina; Shallwani, Shirin Mehdi; Aburub, Ala'; Bennell, Kim L; Van der Esch, Martin; Simic, Milena; McConnell, Sara; Harmer, Alison; Kenny, Glen P; Paterson, Gail; Regnaux, Jean-Philippe; Lefevre-Colau, Marie-Martine; McLean, Linda

    2017-05-01

    To identify effective strengthening exercise programs and provide rehabilitation teams and patients with updated, high-quality recommendations concerning traditional land-based exercises for knee osteoarthritis. A systematic search and adapted selection criteria included comparative controlled trials with strengthening exercise programs for patients with knee osteoarthritis. A panel of experts reached consensus on the recommendations using a Delphi survey. A hierarchical alphabetical grading system (A, B, C+, C, D, D+ or D-) was based on statistical significance ( p osteoarthritis management within a six-month period. Strengthening exercise programs demonstrated a significant improvement for pain relief (four Grade A, ten Grade B, two Grade C+), physical function (four Grade A, eight Grade B) and quality of life (three Grade B). Strengthening in combination with other types of exercises (coordination, balance, functional) showed a significant improvement in pain relief (three Grade A, 11 Grade B, eight Grade C+), physical function (two Grade A, four Grade B, three Grade C+) and quality of life (one Grade A, one Grade C+). There are a variety of choices for strengthening exercise programs with positive recommendations for healthcare professionals and knee osteoarthritis patients. There is a need to develop combined behavioral and muscle-strengthening strategies to improve long-term maintenance of regular strengthening exercise programs.

  13. Strengthening the Canadian alcohol advertising regulatory system.

    Science.gov (United States)

    Heung, Carly M; Rempel, Benjamin; Krank, Marvin

    2012-05-24

    Research evidence points to harmful effects from alcohol advertising among children and youth. In particular, exposure to alcohol advertising has been associated with adolescents drinking both earlier and heavier. Although current federal and provincial guidelines have addressed advertising practices to prevent underage drinking, practice has not been supported by existing policy. While protective measures such as social marketing campaigns have the potential for counteracting the effects from alcohol advertising, the effectiveness of such measures can be easily drowned out with increasing advertising activities from the alcohol industry, especially without effective regulation. Research reviewed by the European Focus on Alcohol Safe Environment (FASE) Project has identified a set of key elements that are necessary to make alcohol advertising policy measures effective at protecting children and youth from the harmful effects of alcohol marketing. Using these key elements as an evaluation framework, there are critical components in the Canadian alcohol advertising regulatory system that clearly require strengthening. To protect impressionable children and youth against the harmful effects of alcohol advertising, 13 recommendations to strengthen current alcohol advertising regulations in Canada are provided for Canadian policy-makers, advertising standard agencies, and public health groups.

  14. Development oxide dispersion strengthened ferritic steels for fusion

    Energy Technology Data Exchange (ETDEWEB)

    Mukhopadhyay, D.K.; Froes, F.H.; Gelles, D.S. [Pacific Northwest National Lab., Richland, WA (United States)

    1997-04-01

    Uniaxial tension creep response is reported for an oxide dispersion strengthened (ODS) steel, Fe-13.5Cr-2W-0.5Ti-0.25 Y{sub 2}O{sub 3} (in weight percent) manufactured using the mechanical alloying process. Acceptable creep response is obtained at 900{degrees}C.

  15. From Seed to Table : Strengthening Urban Farmers' Organizational ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    From Seed to Table : Strengthening Urban Farmers' Organizational and Marketing Skills (Middle East and North Africa). RUAF (Resource Centres on Urban Agriculture and Food Security) was established in 1999 in response to an expressed need on the part of organizations and local governments in the South for a ...

  16. Microstructural influences on strengthening in a naturally aged and overaged Al–Cu–Li–Mg based alloy

    International Nuclear Information System (INIS)

    Ovri, Henry; Jägle, Eric A.; Stark, Andreas; Lilleodden, Erica T.

    2015-01-01

    A combination of transmission electron microscopy, atom probe tomography and high-energy X-ray diffraction was employed to investigate the influence of local microstructural changes on strengthening in a commercial Al–Cu–Li–Mg based alloy, AA2198, in the stretched and naturally aged, and overaged states. Strengthening in the stretched and naturally aged temper was shown to be governed by a combination of Cu–Cu clusters, δ′/β′ phase and solution strengthening. This is in contrast to another report which suggests that strength in this temper is only due to Cu-rich clusters [B. Decreus, et al., Acta Mater., 61 (2013) 2207]. On the other hand, although large volume fractions of equilibrium phases such as T B , and θ were present in the overaged temper, its strengthening was largely governed by order hardening, which is the strengthening mechanism associated with the δ′/β′ phase. The δ′/β′ phase remained in the matrix even after extensive overaging

  17. Microstructural influences on strengthening in a naturally aged and overaged Al–Cu–Li–Mg based alloy

    Energy Technology Data Exchange (ETDEWEB)

    Ovri, Henry, E-mail: henry.ovri@hzg.de [Helmholtz Zentrum Geesthacht, Institute of Materials Research, Materials Mechanics, 21502 Geesthacht (Germany); Jägle, Eric A. [Max-Planck-Institut für Eisenforschung GmbH, Department of Microstructure Physics and Alloy Design, 40237 Düsseldorf (Germany); Stark, Andreas [Helmholtz Zentrum Geesthacht, Institute of Materials Research, Materials Physics, 21502 Geesthacht (Germany); Lilleodden, Erica T. [Helmholtz Zentrum Geesthacht, Institute of Materials Research, Materials Mechanics, 21502 Geesthacht (Germany)

    2015-06-18

    A combination of transmission electron microscopy, atom probe tomography and high-energy X-ray diffraction was employed to investigate the influence of local microstructural changes on strengthening in a commercial Al–Cu–Li–Mg based alloy, AA2198, in the stretched and naturally aged, and overaged states. Strengthening in the stretched and naturally aged temper was shown to be governed by a combination of Cu–Cu clusters, δ′/β′ phase and solution strengthening. This is in contrast to another report which suggests that strength in this temper is only due to Cu-rich clusters [B. Decreus, et al., Acta Mater., 61 (2013) 2207]. On the other hand, although large volume fractions of equilibrium phases such as T{sub B}, and θ were present in the overaged temper, its strengthening was largely governed by order hardening, which is the strengthening mechanism associated with the δ′/β′ phase. The δ′/β′ phase remained in the matrix even after extensive overaging.

  18. Improving the use of health data for health system strengthening

    Directory of Open Access Journals (Sweden)

    Tara Nutley

    2013-02-01

    Full Text Available Background: Good quality and timely data from health information systems are the foundation of all health systems. However, too often data sit in reports, on shelves or in databases and are not sufficiently utilised in policy and program development, improvement, strategic planning and advocacy. Without specific interventions aimed at improving the use of data produced by information systems, health systems will never fully be able to meet the needs of the populations they serve. Objective: To employ a logic model to describe a pathway of how specific activities and interventions can strengthen the use of health data in decision making to ultimately strengthen the health system. Design: A logic model was developed to provide a practical strategy for developing, monitoring and evaluating interventions to strengthen the use of data in decision making. The model draws on the collective strengths and similarities of previous work and adds to those previous works by making specific recommendations about interventions and activities that are most proximate to affect the use of data in decision making. The model provides an organizing framework for how interventions and activities work to strengthen the systematic demand, synthesis, review, and use of data. Results: The logic model and guidance are presented to facilitate its widespread use and to enable improved data-informed decision making in program review and planning, advocacy, policy development. Real world examples from the literature support the feasible application of the activities outlined in the model. Conclusions: The logic model provides specific and comprehensive guidance to improve data demand and use. It can be used to design, monitor and evaluate interventions, and to improve demand for, and use of, data in decision making. As more interventions are implemented to improve use of health data, those efforts need to be evaluated.

  19. EBR Strengthening Technique for Concrete, Long-Term Behaviour and Historical Survey

    Directory of Open Access Journals (Sweden)

    Christoph Czaderski

    2018-01-01

    Full Text Available Epoxy bonded steel plates (externally bonded reinforcemen: EBR for the strengthening of concrete structures were introduced to the construction industry in the late 1960s, and the use of fibre reinforced polymers (FRPs was introduced in the 1990s, which means that these techniques have already been used in construction for 50 and 25 years, respectively. In the first part of the paper, a historical survey of the development and introduction of these strengthening techniques into the construction industry are presented. The monitoring of such applications in construction is very important and gives more confidence to this strengthening technique. Therefore, in the second part of the paper, two long-term monitoring campaigns over an extraordinarily long duration will be presented. Firstly, a 47-year monitoring campaign on a concrete beam with an epoxy bonded steel plate and, secondly, a 20-year monitoring campaign on a road bridge with epoxy bonded CFRP (carbon fibre reinforced polymers strips are described. The paper is an expanded version of the paper presented at the SMAR2017 Conference.

  20. Effect of sulphur on the strengthening of a Zr-Nb alloy

    International Nuclear Information System (INIS)

    Chang, K.I.; Hong, S.I.

    2008-01-01

    The effect of sulphur on the strengthening and the thermally activated deformation of cold-worked Zr-1 Nb alloy was investigated. In the present study, the sulphur strengthening was observed even at room temperature unlike the previous study of Ferrer et al. The flow stress increased by 65 MPa at room temperature with the addition of sulphur as little as 20 ppm. With further increase of sulphur content up to 300 ppm, negligible change of the flow stress was observed. The additive strengthening behavior in which the entire stress-strain curve shift upward by the friction stress due to the addition of sulphur was observed in the Zr-Nb alloy of the present study. The activation volume decreased slightly (from 110b 3 to 80b 3 ) with the addition of 300 ppm sulphur at room temperature. The rate-controlling mechanism of the deformation can best be explained by the dislocation interaction mechanism in which the segregation of alloying elements such as oxygen and sulphur atoms affects the activation length of dislocations

  1. Strengthening Institutions and Enterprises of Cooperative and Their Impact on Members’ Assets

    Directory of Open Access Journals (Sweden)

    Sri Widiyati Soemodipoero

    2017-06-01

    Full Text Available Revitalization of Cooperative interpreted as a series of activities undertaken to reorganize the institutional and strengthen cooperative efforts in accordance with the values and principles of cooperatives. Cooperative serves as a tool to equalize the concentration of control of economic assets so that the weak economy may have opportunities to enhance economic independence. The purpose of this study is to explore the link between the level of member participation and human resource competencies to the strengthening of the institutional and cooperative efforts as well as its impact on member assets. This research used logistic regression analysis and Wilcoxon Signed Rank Test. The results showed that the level of participation of members and managers of Human Resources competencies significantly affect institutional strengthening and cooperative efforts. Different test shows that there is a difference between financial capital and human capital before and after become a member of the cooperative.

  2. Animal-assisted intervention and social skills strengthening

    OpenAIRE

    Božič, Tjaša

    2014-01-01

    The diploma thesis describe animal-assisted interventions, more precisely, the significance of animal-assisted interventions for strengthening of social skills. Theoretical part includes a detailed presentation of the benefits of therapeutic dog in work with vulnerable populations. I focused on delimitation of the term animal-assisted interventions which includes animal-assisted therapy and animal-assisted activity and the differences and similarities between them. I continued with therapeuti...

  3. Cell-surface proteoglycan in sea urchin primary mesenchyme cell migration

    International Nuclear Information System (INIS)

    Lane, M.C.

    1989-01-01

    Early in the development of the sea urchin embryo, the primary mesenchyme cells (PMC) migrate along the basal lamina of the blastocoel. Migration is inhibited in L. pictus embryos cultured in sulfate-free seawater and in S. purpuratus embryos exposed to exogenous β-D-xylosides. An in vitro assay was developed to test the migratory capacity of normal PMC on normal and treated blastocoelic matrix. Sulfate deprivation and exposure to exogenous xyloside render PMC nonmotile on either matrix. Materials removed from the surface of normal PMC by treatment with 1 M urea restored migratory ability to defective cells, whereas a similar preparation isolated from the surface of epithelial cells at the same stage did not. Migration also resumed when cells were removed from the xyloside or returned to normal seawater. The urea extract was partially purified and characterized by radiolabeling, gel electrophoresis, fluorography, ion exchange chromatography, and western blotting. The PMC synthesize a large chondroitin sulfate/dermatan sulfate proteoglycan that is present in an active fraction isolated by chromatography. Chondroitinase ABC digestion of live cells blocked migration reversibly, further supporting the identification of the chondroitin sulfate/dermatan sulfate proteoglycan as the active component in the urea extract. Much of the incorporated sulfate was distributed along the filopodia in 35 SO 4 -labelled PMC by autoradiography. The morphology of normal and treated S. purpuratus PMC was examined by scanning electron microscopy, and differences in spreading, particularly of the extensive filopodia present on the cells, was observed. A model for the role of the chondroitin sulfate/dermatan sulfate proteoglycan in cell detachment during migration is proposed

  4. Aging stem cells. A Werner syndrome stem cell model unveils heterochromatin alterations as a driver of human aging.

    Science.gov (United States)

    Zhang, Weiqi; Li, Jingyi; Suzuki, Keiichiro; Qu, Jing; Wang, Ping; Zhou, Junzhi; Liu, Xiaomeng; Ren, Ruotong; Xu, Xiuling; Ocampo, Alejandro; Yuan, Tingting; Yang, Jiping; Li, Ying; Shi, Liang; Guan, Dee; Pan, Huize; Duan, Shunlei; Ding, Zhichao; Li, Mo; Yi, Fei; Bai, Ruijun; Wang, Yayu; Chen, Chang; Yang, Fuquan; Li, Xiaoyu; Wang, Zimei; Aizawa, Emi; Goebl, April; Soligalla, Rupa Devi; Reddy, Pradeep; Esteban, Concepcion Rodriguez; Tang, Fuchou; Liu, Guang-Hui; Belmonte, Juan Carlos Izpisua

    2015-06-05

    Werner syndrome (WS) is a premature aging disorder caused by WRN protein deficiency. Here, we report on the generation of a human WS model in human embryonic stem cells (ESCs). Differentiation of WRN-null ESCs to mesenchymal stem cells (MSCs) recapitulates features of premature cellular aging, a global loss of H3K9me3, and changes in heterochromatin architecture. We show that WRN associates with heterochromatin proteins SUV39H1 and HP1α and nuclear lamina-heterochromatin anchoring protein LAP2β. Targeted knock-in of catalytically inactive SUV39H1 in wild-type MSCs recapitulates accelerated cellular senescence, resembling WRN-deficient MSCs. Moreover, decrease in WRN and heterochromatin marks are detected in MSCs from older individuals. Our observations uncover a role for WRN in maintaining heterochromatin stability and highlight heterochromatin disorganization as a potential determinant of human aging. Copyright © 2015, American Association for the Advancement of Science.

  5. Cigarette smoke suppresses Bik to cause epithelial cell hyperplasia and mucous cell metaplasia.

    Science.gov (United States)

    Mebratu, Yohannes A; Schwalm, Kurt; Smith, Kevin R; Schuyler, Mark; Tesfaigzi, Yohannes

    2011-06-01

    Aberrant regulation of airway epithelial cell numbers in airways leads to increased mucous secretions in chronic lung diseases such as chronic bronchitis. Because the Bcl-2 family of proteins is crucial for airway epithelial homeostasis, identifying the players that reduce cigarette smoke (CS)-induced mucous cell metaplasia can help to develop effective therapies. To identify the Bcl-2 family of proteins that play a role in reducing CS-induced mucous cell metaplasia. We screened for dysregulated expression of the Bcl-2 family members. We identified Bik to be significantly reduced in bronchial brushings of patients with chronic epithelial cell hyperplasia compared with nondiseased control subjects. Reduced Bik but increased MUC5AC mRNA levels were also detected when normal human airway epithelial cells (HAECs) were exposed to CS or when autopsy tissues from former smokers with and without chronic bronchitis were compared. Similarly, exposure of C57Bl/6 mice to CS resulted in increased numbers of epithelial and mucous cells per millimeter of basal lamina, along with reduced Bik but increased Muc5ac expression, and this change was sustained even when mice were allowed to recover in filtered air for 8 weeks. Restoring Bik expression significantly suppressed CS-induced mucous cell metaplasia in differentiated primary HAEC cultures and in airways of mice in vivo. Bik blocked nuclear translocation of phospho-ERK1/2 to induce apoptosis of HAECs. The conserved Leu61 within Bik and ERK1/2 activation were essential to induce cell death in hyperplastic mucous cells. These studies show that CS suppresses Bik expression to block airway epithelia cell death and thereby increases epithelial cell hyperplasia in chronic bronchitis.

  6. Solute strengthening effects for 316 stainless steel at elevated temperature

    International Nuclear Information System (INIS)

    Park, Nam Ju; Lee, Sang Mae

    1986-01-01

    The inelastic behavior of 316 stainless steel is studied in order to investigate the solute strengthening effects. The Arrhenius-type rate equation with inclusion of the Voce-type evolution phenomenon is extended by addition of solute strengthening term to the isotropic work hardening effect. Changing of strain rate and temperature during the tension tests, we found that the strong work hardening for the inelastic of 316 stainless steel resulted from the vacancy-interstitial pair mechanism. Thus, the calculated results using the extended constitutive equations including solute effect due to the vacancy-interstitial pair mechanism were found to be in good agreement with the stress-strain curves obtained from the tension tests. (Author)

  7. Angiogenesis in the reparatory mucosa of the mandibular edentulous ridge is driven by endothelial tip cells.

    Science.gov (United States)

    Stănescu, Ruxandra; Didilescu, Andreea Cristiana; Jianu, Adelina Maria; Rusu, M C

    2012-01-01

    Sprouting angiogenesis is led by specialized cell--the endothelial tip cells (ETCs) which can be targeted by pro- or anti-angiogenic therapies. We aimed to perform a qualitative study in order to assess the guidance by tip cells of the endothelial sprouts in the repairing mucosa of the edentulous mandibular crest. Mucosa of the mandibular edentulous ridge was collected from six adult patients, prior to healing abutment placement (second surgery). Slides were prepared and immunostained with antibodies for CD34 and Ki67. The abundant vasculature of the lamina propria was observed on slides and the CD34 antibodies labeled endothelial tip cells in various stages of the endothelial sprouts. Ki67 identified positive endothelial cells, confirming the proliferative status of the microvascular bed. According to the results, the in situ sprouting angiogenesis is driven by tip cells in the oral mucosa of the edentulous ridge and these cells can be targeted by various therapies, as required by the local pathologic or therapeutic conditions.

  8. Effects of Mn partitioning on nanoscale precipitation and mechanical properties of ferritic steels strengthened by NiAl nanoparticles

    International Nuclear Information System (INIS)

    Jiao, Z.B.; Luan, J.H.; Miller, M.K.; Yu, C.Y.; Liu, C.T.

    2015-01-01

    The critical role of Mn partitioning in the formation of ordered NiAl nanoparticles in ferritic steels has been examined through a combination of atom probe tomography (APT) and thermodynamic and first-principles calculations. Our APT study reveals that Mn partitions to the NiAl nanoparticles, and dramatically increases the particle number density by more than an order of magnitude, leading to a threefold enhancement in strengthening. Atomistic structural analyses reveal that Mn is energetically favored to partition to the NiAl nanoparticles by preferentially occupying the Al sublattice, which not only increases the driving force, but also reduces the strain energy for nucleation, thereby significantly decreasing the critical energy for formation of the NiAl nanoparticles in ferritic steels. In addition, the effects of Mn on the precipitation strengthening mechanisms were quantitatively evaluated in terms of chemical strengthening, coherency strengthening, modulus strengthening and order strengthening

  9. The Strengthening Families Initiative and Child Care Quality Improvement: How Strengthening Families Influenced Change in Child Care Programs in One State

    Science.gov (United States)

    Douglass, Anne; Klerman, Lorraine

    2012-01-01

    Research Findings: This study investigated how the Strengthening Families through Early Care and Education initiative in Illinois (SFI) influenced change in 4 child care programs. Findings indicate that SFI influenced quality improvements through 4 primary pathways: (a) Learning Networks, (b) the quality of training, (c) the engagement of program…

  10. Strengthening Health Information Systems to Support Post-Disaster ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Strengthening Health Information Systems to Support Post-Disaster Healthcare in Haiti. The occurrence of a natural disaster may seem to carry repercussions that are indiscriminate in nature; however, it is the vulnerable populations that suffer most during such events, and in the days, months and years that follow. In Haiti ...

  11. CFRP strengthened openings in two-way concrete slabs

    DEFF Research Database (Denmark)

    Enochsson, O.; Lundqvist, J.; Täljsten, Björn

    2006-01-01

    are very suitable, not only because of their strength, but also due to that they are easy to apply in comparison to traditional steel girders or other lintel systems. Even though many benefits have been shown by strengthening openings with FRPs not much research have been presented in the literature...

  12. Conceptual Precalculus: Strengthening Students' Quantitative and Covariational Reasoning

    Science.gov (United States)

    Madison, Bernard L.; Carlson, Marilyn; Oehrtman, Michael; Tallman, Michael

    2015-01-01

    Research over the past few decades points to ways precalculus and calculus courses can be strengthened to improve student learning in these courses. This research has informed the development of the Algebra and Precalculus Concept Readiness (APCR) and the Calculus Concept Readiness (CCR) assessments. In this article, the authors present three…

  13. Creep and rupture of an ODS alloy with high stress rupture ductility. [Oxide Dispersion Strengthened

    Science.gov (United States)

    Mcalarney, M. E.; Arsons, R. M.; Howson, T. E.; Tien, J. K.; Baranow, S.

    1982-01-01

    The creep and stress rupture properties of an oxide (Y2O3) dispersion strengthened nickel-base alloy, which also is strengthened by gamma-prime precipitates, was studied at 760 and 1093 C. At both temperatures, the alloy YDNiCrAl exhibits unusually high stress rupture ductility as measured by both elongation and reduction in area. Failure was transgranular, and different modes of failure were observed including crystallographic fracture at intermediate temperatures and tearing or necking almost to a chisel point at higher temperatures. While the rupture ductility was high, the creep strength of the alloy was low relative to conventional gamma prime strengthened superalloys in the intermediate temperature range and to ODS alloys in the higher temperature range. These findings are discussed with respect to the alloy composition; the strengthening oxide phases, which are inhomogeneously dispersed; the grain morphology, which is coarse and elongated and exhibits many included grains; and the second phase inclusion particles occurring at grain boundaries and in the matrix. The creep properties, in particular the high stress dependencies and high creep activation energies measured, are discussed with respect to the resisting stress model of creep in particle strengthened alloys.

  14. JAIF formulates policy for strengthening foundation of nuclear industry

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    With recognition that conditions surrounding the nuclear industry are becoming severe with the slowdown in the growth of the Japanese economy, the Japan Atomic Industrial Forum has been discussing ways and means of strengthening the foundations of the nuclear industry. A subcommittee of the Power Reactor Development Committee has been formed. It comprizes two divisions. The first division focused on economic and social prospects for the future and other basic questions. The second division dealt with specific problems viewed from the position of the nuclear quipment supply industry and measures to resolve them. The report was prepared based on the studies done by the two divisions, and focusing on the strengthening of the basis of the nuclear industry through the year 2010. The report estimates that construction of nuclear power plants will be less than 2 units a year in the coming five year period, and will continue at about 2 units a year until about the year 2000. From this outlook, it discusses the work facing the nuclear industry and the steps to be taken to reduce nuclear power generation costs, efficient research and development and the promotion of international cooperation. The report covers four sections: the position of nuclear power development in the national economy; the present state and tasks of the nuclear industry and the nuclear equipment supply industry; measures for maintaining and strengthening the foundations of the nuclear industry, and the tasks to be done. (Nogami, K.)

  15. Seismic strengthening of RC structures with exterior shear walls

    Indian Academy of Sciences (India)

    Nowadays, most of the strengthening strategies are based on global ..... In the present work, sliding shear capacity was calculated based on the code formulations, ... This study has been carried out with the financial support of State Planning ...

  16. Acoustic emission monitoring of concrete columns and beams strengthened with fiber reinforced polymer sheets

    Science.gov (United States)

    Ma, Gao; Li, Hui; Zhou, Wensong; Xian, Guijun

    2012-04-01

    Acoustic emission (AE) technique is an effective method in the nondestructive testing (NDT) field of civil engineering. During the last two decades, Fiber reinforced polymer (FRP) has been widely used in repairing and strengthening concrete structures. The damage state of FRP strengthened concrete structures has become an important issue during the service period of the structure and it is a meaningful work to use AE technique as a nondestructive method to assess its damage state. The present study reports AE monitoring results of axial compression tests carried on basalt fiber reinforced polymer (BFRP) confined concrete columns and three-point-bending tests carried on BFRP reinforced concrete beams. AE parameters analysis was firstly utilized to give preliminary results of the concrete fracture process of these specimens. It was found that cumulative AE events can reflect the fracture development trend of both BFRP confined concrete columns and BFRP strengthened concrete beams and AE events had an abrupt increase at the point of BFRP breakage. Then the fracture process of BFRP confined concrete columns and BFRP strengthened concrete beams was studied through RA value-average frequency analysis. The RA value-average frequency tendencies of BFRP confined concrete were found different from that of BFRP strengthened concrete beams. The variation tendency of concrete crack patterns during the loading process was revealed.

  17. Strengthening of stainless steel weldment by high temperature precipitation

    Directory of Open Access Journals (Sweden)

    Sergio Neves Monteiro

    2017-10-01

    Full Text Available The mechanical behavior and the strengthening mechanism of stainless steel welded joints at 600 °C have been investigated. The welds were composed of AISI 304 stainless steel, as base metal, and niobium containing AISI 347 stainless steel, as weld metal. The investigation was conducted by means of creep tests. The welded specimens were subjected to both high temperature (600 °C and long periods (up to 2000 h under constant load, and both mechanical properties and microstructural changes in the material were monitored. It was found that the exposure of the material at 600 °C under load contributes to a strengthening effect on the weld. The phenomenon might be correlated with an accelerated process of second phase precipitation hardening. Keywords: Stainless steel, Weld, AISI 304, Precipitation hardening

  18. A new ultrahigh-strength stainless steel strengthened by various coexisting nanoprecipitates

    Energy Technology Data Exchange (ETDEWEB)

    Xu, W., E-mail: w.xu@m2i.nl [Materials Innovation Institute M2i, Kluyverweg 1, 2629 HS, Delft (Netherlands)] [Novel Aerospace Materials (NovAM) Group, Faculty of Aerospace Engineering, Delft University of Technology, Kluyverweg 1, 2629 HS, Delft (Netherlands); Rivera-Diaz-del-Castillo, P.E.J. [Novel Aerospace Materials (NovAM) Group, Faculty of Aerospace Engineering, Delft University of Technology, Kluyverweg 1, 2629 HS, Delft (Netherlands); Yan, W.; Yang, K. [Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016 (China); San Martin, D. [Materalia Group, Department of Physical Metallurgy, Centro Nacional de Investigaciones Metalurgicas (CENIM-CSIC), Av. Gregorio del Amo 8, 28040 Madrid (Spain); Kestens, L.A.I. [Department of Materials Science and Engineering, Ghent University, Technologiepark 903, 9052 Gent (Belgium); Zwaag, S. van der [Novel Aerospace Materials (NovAM) Group, Faculty of Aerospace Engineering, Delft University of Technology, Kluyverweg 1, 2629 HS, Delft (Netherlands)

    2010-06-15

    A general computational alloy design approach based on thermodynamic and physical metallurgical principles and coupled with a genetic optimization scheme is presented. The model is applied to develop a new ultrahigh-strength maraging stainless steel. The alloy composition and heat treatment parameters are integrally optimized so as to achieve microstructures of fully lath martensite matrix strengthened by multiple precipitates of MC carbides, Cu particles and Ni{sub 3}Ti intermetallics. The combined mechanical properties, corrosion resistance and identification of actual strengthening precipitates in the experimental prototype produced on the basic of the model predictions provide a strong justification for the alloy design approach.

  19. A new ultrahigh-strength stainless steel strengthened by various coexisting nanoprecipitates

    International Nuclear Information System (INIS)

    Xu, W.; Rivera-Diaz-del-Castillo, P.E.J.; Yan, W.; Yang, K.; San Martin, D.; Kestens, L.A.I.; Zwaag, S. van der

    2010-01-01

    A general computational alloy design approach based on thermodynamic and physical metallurgical principles and coupled with a genetic optimization scheme is presented. The model is applied to develop a new ultrahigh-strength maraging stainless steel. The alloy composition and heat treatment parameters are integrally optimized so as to achieve microstructures of fully lath martensite matrix strengthened by multiple precipitates of MC carbides, Cu particles and Ni 3 Ti intermetallics. The combined mechanical properties, corrosion resistance and identification of actual strengthening precipitates in the experimental prototype produced on the basic of the model predictions provide a strong justification for the alloy design approach.

  20. Strengthening by ordered precipitates in a Ni--Ni4Mo system

    International Nuclear Information System (INIS)

    Goodrum, J.W.; LeFevre, B.G.

    1977-01-01

    The strength characteristics and microstructures of aged Ni-Mo alloys containing ordered (Ni 4 Mo) precipitates were studied as a function of aging time and temperature. It was found that 17 at. percent Mo alloy aged at 750 0 C produced a uniform dispersion of cuboidal β precipitates which coarsened with time producing a gradual increase in flow stress. The flow stress increment was found to vary in qualitative agreement with both order strengthening and coherency strain models. Both these models give over-estimates of the strengthening increment. A negative dependence of flow stress on temperature is attributed to coherency strain contributions

  1. Computational design of precipitation-strengthened titanium-nickel-based shape memory alloys

    Science.gov (United States)

    Bender, Matthew D.

    Motivated by performance requirements of future medical stent applications, experimental research addresses the design of novel TiNi-based, superelastic shape-memory alloys employing nanoscale precipitation strengthening to minimize accommodation slip for cyclic stability and to increase output stress capability for smaller devices. Using a thermodynamic database describing the B2 and L21 phases in the Al-Ni-Ti-Zr system, Thermo-Calc software was used to assist modeling the evolution of phase composition during 600°C isothermal evolution of coherent L21 Heusler phase precipitation from supersaturated TiNi-based B2 phase matrix in an alloy experimentally characterized by atomic-scale Local Electrode Atom Probe (LEAP) microanalysis. Based on measured evolution of the alloy hardness (under conditions stable against martensitic transformation) a model for the combined effects of solid solution strengthening and precipitation strengthening was calibrated, and the optimum particle size for efficient strengthening was identified. Thermodynamic modeling of the evolution of measured phase fractions and compositions identified the interfacial capillary energy enabling thermodynamic design of alloy microstructure with the optimal strengthening particle size. Extension of alloy designs to incorporate Pt and Pd for reducing Ni content, enhancing radiopacity, and improving manufacturability were considered using measured Pt and Pd B2/L2 1 partitioning coefficients. After determining that Pt partitioning greatly increases interphase misfit, full attention was devoted to Pd alloy designs. A quantitative approach to radiopacity was employed using mass attenuation as a metric. Radiopacity improvements were also qualitatively observed using x-ray fluoroscopy. Transformation temperatures were experimentally measured as a function of Al and Pd content. Redlich-Kister polynomial modeling was utilized for the dependence of transformation reversion Af temperature on B2 matrix phase

  2. Development of Austenitic ODS Strengthened Alloys for Very High Temperature Applications

    Energy Technology Data Exchange (ETDEWEB)

    Stubbins, James [Univ. of Illinois, Urbana-Champaign, IL (United States); Heuser, Brent [Univ. of Illinois, Urbana-Champaign, IL (United States); Robertson, Ian [Kyushu Univ. (Japan); Sehitoglu, Huseyin [Univ. of Illinois, Urbana-Champaign, IL (United States); Sofronis, Petros [Kyushu Univ. (Japan); Gewirth, Andrew [Kyushu Univ. (Japan)

    2015-04-22

    This “Blue Sky” project was directed at exploring the opportunities that would be gained by developing Oxide Dispersion Strengthened (ODS) alloys based on the Fe-Cr-Ni austenitic alloy system. A great deal of research effort has been directed toward ferritic and ferritic/martensitic ODS alloys which has resulted in reasonable advances in alloy properties. Similar gains should be possible with austenitic alloy which would also take advantage of other superior properties of that alloy system. The research effort was aimed at the developing an in-depth understanding of the microstructural-level strengthening effects of ODS particles in austentic alloys. This was accomplished on a variety of alloy compositions with the main focus on 304SS and 316SS compositions. A further goal was to develop an understanding other the role of ODS particles on crack propagation and creep performance. Since these later two properties require bulk alloy material which was not available, this work was carried out on promising austentic alloy systems which could later be enhanced with ODS strengthening. The research relied on a large variety of micro-analytical techniques, many of which were available through various scientific user facilities. Access to these facilities throughout the course of this work was instrumental in gathering complimentary data from various analysis techniques to form a well-rounded picture of the processes which control austenitic ODS alloy performance. Micromechanical testing of the austenitic ODS alloys confirmed their highly superior mechanical properties at elevated temperature from the enhanced strengthening effects. The study analyzed the microstructural mechanisms that provide this enhanced high temperature performance. The findings confirm that the smallest size ODS particles provide the most potent strengthening component. Larger particles and other thermally- driven precipitate structures were less effective contributors and, in some cases, limited

  3. Small Grants Program : Strengthening ICTD Research Capacity in ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    On the one hand, ICTs can provide access to tools and content to improve economic conditions, strengthen social networks, democratize the flow of information, and reduce risk to citizens from pandemics and natural disasters. On the other hand, ICTs can be used to engage in exclusionary or criminal practices, or contribute ...

  4. How Can Comparison Groups Strengthen Regression Discontinuity Designs?

    Science.gov (United States)

    Wing, Coady; Cook, Thomas D.

    2011-01-01

    In this paper, the authors examine some of the ways that different types of non-equivalent comparison groups can be used to strengthen causal inferences based on regression discontinuity design (RDD). First, they consider a design that incorporates pre-test data on assignment scores and outcomes that were collected either before the treatment…

  5. 1 The West Africa Initiative to Strengthen Capacities through Health ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Afekwo Mbonu

    2012-08-31

    ) governance and governance structures of health systems. .... Strengthened evidence base from the awarded research projects complemented by a set of ..... Canadian recipients which purchase equipment using IDRC funds ...

  6. Children's Books in Review: Books on Strengthening Family Ties.

    Science.gov (United States)

    Winfield, Evelyn T.

    1991-01-01

    Reviews children's books that emphasize the strengthening of family ties. Characters in the books realize the importance and influence of family relationships as they struggle with sibling rivalry, self-discovery, peer relationships, a search for heritage, adoption, and death. (SM)

  7. Strengthening local seed systems within the bean value chain ...

    African Journals Online (AJOL)

    Strengthening local seed systems within the bean value chain: Experience of agricultural innovation platforms in the Democratic Republic of Congo. ... associations, local grain/seed traders, private and public extension agents, researchers, finance and credit cooperatives and Non-Governmental Organisations (NGOs).

  8. STRENGTHENING CONCRETE HOLLOW SECTION GIRDER BRIDGE USING POLYURETHANE-CEMENT MATERIAL (PART B

    Directory of Open Access Journals (Sweden)

    Haleem K. Hussain

    2018-01-01

    Full Text Available This paper presents experimental study to retrofitted reinforced concrete Hollow Section Bridge. The study was carried out on the White River Bridge structure (Bai xi da Qiao / China. The effect of retrofitting on stress and strain of beams at the critical section was studied. Evaluating the bridges girder after strengthening using new material called PolyurethaneCement material (PUC as an external material .This study present the strain and deflection before and after strengthening the bridge girders. The results has shown that the overall state of the bridge structural strengthening is in good condition. The enhancement was significant in stiffness of the bridge structure. Regarding to the results of static load test, the experimental values strain and deflection are less than theoretical values, indicating that the stiffness of the structure, overall deformation and integrity satisfy the designed and standard requirements and the working performance are in good condition, and flexure capacity has a certain surplus.

  9. EMOTIONAL STRENGTHENING IN THE FAMILY: INTERVENTION FROM THE SCHOOL CONTEXT

    Directory of Open Access Journals (Sweden)

    Jael Alejandra Vargas Rubilar

    2012-06-01

    Full Text Available The psychological consequences from relational styles characterized by lack of affection and interactional mismanagement between family members can inhibit or block the attempt by members to achieve their full potential for healthy psy -chosocial development. In this context, emotional strengthening families would become a key condition for overcoming these dysfunctional patterns.The aim of this work is to show why psychoeducation and emotional stimula-tion can be particularly useful in the context of psychosocial risk due to poverty and present some strategies to approach such goal from the school environment. This approach is mainly focused on the strengthening of emotional resources in parents and primary caregivers to achieve a direct impact on the children’s emo-tional development.

  10. Strengthening mechanisms in an inertia friction welded nickel-base superalloy

    Energy Technology Data Exchange (ETDEWEB)

    Tiley, J.S., E-mail: Jaimie.Tiley@us.af.mil [Air Force Research Laboratory, Wright Patterson Air Force Base, OH 45433 (United States); Mahaffey, D.W. [Air Force Research Laboratory, Wright Patterson Air Force Base, OH 45433 (United States); Alam, T.; Rojhirunsakool, T. [Department of Materials Engineering, University of North Texas, Denton, TX 76203 (United States); Senkov, O.; Parthasarthy, T. [Air Force Research Laboratory, Wright Patterson Air Force Base, OH 45433 (United States); UES, Inc., Dayton, OH 45433 (United States); Banerjee, R. [Department of Materials Engineering, University of North Texas, Denton, TX 76203 (United States)

    2016-04-26

    This research investigated the strengthening mechanisms associated with the as-welded microstructure developed during inertia friction welding of dissimilar superalloys LHSR and Mar-M247. The weld interface and heat affected regions of the sample were analyzed using hardness indentation techniques and subsequently characterized using SEM, TEM and advanced atom probe tomography. The yield strength of the welded joint was modeled to determine the impact of the gradients in the as-welded microstructure on strengthening mechanisms within the LSHR material. Characterization centered on formation of γ′, γ grain size and chemical segregation within the heat affected regions. Results indicate an increased hardness in the vicinity of the weld interface, resulting from the refined dispersion of γ′ and γ grains.

  11. Intermetallic Strengthened Alumina-Forming Austenitic Steels for Energy Applications

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Bin [Dartmouth College, Hanover, NH (United States); Baker, Ian [Dartmouth College, Hanover, NH (United States)

    2016-03-31

    In order to achieve energy conversion efficiencies of >50 % for steam turbines/boilers in power generation systems, the materials required must be strong, corrosion-resistant at high temperatures (>700°C), and economically viable. Austenitic steels strengthened with Laves phase and L12 precipitates, and alloyed with aluminum to improve oxidation resistance, are potential candidate materials for these applications. The creep resistance of these alloys is significantly improved through intermetallic strengthening (Laves-Fe2Nb + L12-Ni3Al precipitates) without harmful effects on oxidation resistance. Microstructural and microchemical analyses of the recently developed alumina-forming austenitic (AFA) steels (Fe-14Cr-32Ni-3Nb-3Al-2Ti-based) indicated they are strengthened by Ni3Al(Ti) L12, NiAl B2, Fe2Nb Laves phase and MC carbide precipitates. Different thermomechanical treatments (TMTs) were performed on these stainless steels in an attempt to further improve their mechanical properties. The thermo-mechanical processing produced nanocrystalline grains in AFA alloys and dramatically increased their yield strength at room temperature. Unfortunately, the TMTs didn’t increase the yield strengths of AFA alloys at ≥700ºC. At these temperatures, dislocation climb is the dominant mechanism for deformation of TMT alloys according to strain rate jump tests. After the characterization of aged AFA alloys, we found that the largest strengthening effect from L12 precipitates can be obtained by aging for less than 24 h. The coarsening behavior of the L12 precipitates was not influenced by carbon and boron additions. Failure analysis and post-mortem TEM analysis were performed to study the creep failure mechanisms of these AFA steels after creep tests. Though the Laves and B2-NiAl phase precipitated along the boundaries can improve the creep properties, cracks were

  12. Bone augmentation of the osteo-odonto alveolar lamina in MOOKP--will it delay laminar resorption?

    Science.gov (United States)

    Iyer, Geetha; Srinivasan, Bhaskar; Agarwal, Shweta; Rishi, Ekta; Rishi, Pukhraj; Rajan, Gunaseelan; Shanmugasundaram, Shanmugasundaram

    2015-07-01

    We aimed to describe a new technique and analyse the early outcomes of augmenting the canine tooth using a mandibular bone graft in an attempt to delay or retard the process of laminar resorption following the modified osteo odonto keratoprosthesis (MOOKP) procedure. This was a retrospective case series. Eyes that underwent the bone augmentation procedure between December 2012 and February 2014 were retrospectively analysed. The procedure, performed by the oromaxillofacial surgeon, involved securing a mandibular bone graft beneath the periosteum on the labial aspect of the canine tooth chosen to be harvested for the MOOKP procedure. This procedure was performed simultaneously with the Stage 1 A of the MOOKP. Three months later, the tooth was harvested and fashioned into the osteo-odonto alveolar lamina similar to the method described in the Rome-Vienna Protocol. The bone augmentation procedure was performed in 11 eyes (five SJS/ six chemical injuries). The mean follow-up after Stage 2 of MOOKP procedure in these eyes was 7.45 months (2 to 20 months). Complications noted were peripheral laminar exposure (three eyes-SJS) and bone graft exposure and necrosis in the mouth (nine-SJS). No evidence of clinical laminar resorption was noted in any of the eyes. Laminar resorption in MOOKP can lead to vision and globe threatening complications due to the consequent cylinder instability and chances of extrusion. Augmenting the bone on the labial aspect of the canine tooth might have a role to play in delaying or preventing laminar resorption.

  13. Where are we now? The strengthened safeguards system: Origins, aims, features, issues and prospects

    International Nuclear Information System (INIS)

    Schriefer, D.

    1998-01-01

    The present status of the strengthened safeguards system includes the origins, aims, features, issues and future prospects. The areas of emphasis concerning the strengthened safeguards system are: access to information (environmental sampling and improved information analysis), access to sites, rational use of resources (cost analysis of present safeguards, increased cooperation with state systems, cost savings in traditional safeguards activities)

  14. 40 CFR 141.551 - What strengthened combined filter effluent turbidity limits must my system meet?

    Science.gov (United States)

    2010-07-01

    ... effluent turbidity limits must my system meet? 141.551 Section 141.551 Protection of Environment... Effluent Requirements § 141.551 What strengthened combined filter effluent turbidity limits must my system meet? Your system must meet two strengthened combined filter effluent turbidity limits. (a) The first...

  15. Antenatal care strengthening in Jimma, Ethiopia

    DEFF Research Database (Denmark)

    Villadsen, Sarah Fredsted; Tersbøl, Britt Pinkowski; Negussie, Dereje

    2014-01-01

    Objective. We assessed how health system priorities matched user expectations and what the needs for antenatal care (ANC) strengthening were for improved maternal health in Jimma, Ethiopia. Methods. A questionnaire survey among all recent mothers in the study area was conducted to study the content...... was given high priority, and that contributed to a lack of continuity and privacy. To the women, poor user-provider interaction was a serious concern hindering the trust in the health care providers. Further, the care provision was compromised by the inadequate laboratory facilities, unstructured health...

  16. A mechanical model for FRP-strengthened beams in bending

    Directory of Open Access Journals (Sweden)

    P. S. Valvo

    2012-10-01

    Full Text Available We analyse the problem of a simply supported beam, strengthened with a fibre-reinforced polymer (FRP strip bonded to its intrados and subjected to bending couples applied to its end sections. A mechanical model is proposed, whereby the beam and FRP strip are modelled according to classical beam theory, while the adhesive and its neighbouring layers are modelled as an interface having a piecewise linear constitutive law defined over three intervals (elastic response – softening response – debonding. The model is described by a set of differential equations with appropriate boundary conditions. An analytical solution to the problem is determined, including explicit expressions for the internal forces, displacements and interfacial stresses. The model predicts an overall non-linear mechanical response for the strengthened beam, ranging over several stages: from linearly elastic behaviour to damage, until the complete detachment of the FRP reinforcement.

  17. The temporal requirement for vitamin A in the developing eye: mechanism of action in optic fissure closure and new roles for the vitamin in regulating cell proliferation and adhesion in the embryonic retina.

    Science.gov (United States)

    See, Angela Wai-Man; Clagett-Dame, Margaret

    2009-01-01

    Mammalian eye development requires vitamin A (retinol, ROL). The role of vitamin A at specific times during eye development was studied in rat fetuses made vitamin A deficient (VAD) after embryonic day (E) 10.5 (late VAD). The optic fissure does not close in late VAD embryos, and severe folding and collapse of the retina is observed at E18.5. Pitx2, a gene required for normal optic fissure closure, is dramatically downregulated in the periocular mesenchyme in late VAD embryos, and dissolution of the basal lamina does not occur at the optic fissure margin. The addition of ROL to late VAD embryos by E12.5 restores Pitx2 expression, supports dissolution of the basal lamina, and prevents coloboma, whereas supplementation at E13.5 does not. Surprisingly, ROL given as late as E13.5 completely prevents folding of the retina despite the presence of an open fetal fissure, showing that coloboma and retinal folding represent distinct VAD-dependent defects. Retinal folding due to VAD is preceded by an overall reduction in the percentage of cyclin D1 positive cells in the developing retina, (initially resulting in retinal thinning), as well as a dramatic reduction in the cell adhesion-related molecules, N-cadherin and beta-catenin. Reduction of retinal cell number combined with a loss of the normal cell-cell adhesion proteins may contribute to the collapse and folding of the retina that occurs in late VAD fetuses.

  18. Experimental study on flexural members strengthened with variable bonded pre-stressed CFRP plates

    Science.gov (United States)

    Zhang, Baojing; Shang, Shouping

    2017-08-01

    Aiming at the problem that the structural adhesive between CFRP and concrete interface is aging with time and then lost the bond strength, the concept of variable bond prestressed CFRP is put forward. In order to obtain the bearing capacity and failure pattern of the beam strengthened with variable bonding prestressed CFRP plate, three concrete beams of 5.6m long were strengthened by the technology of non-bonding, bonding and variable bonding strengthened with prestressed CFRP plates respectively, the mechanical properties and crack changes of the test beams under three conditions had been compared and analyzed. Test results show that the variable bond strengthened with prestressed CFRP plates with unbonded prestressed CFRP, cracking load was increased by 36%, yield load increased by 4%, the ultimate load increased by 12%; The reinforcement technology of variable bonding prestressed CFRP plate has the characteristics of non-bonding and bonding prestressed CFRP plate reinforcement, which is similar to that of the bonded reinforcement in the early stage of the development of the cracks, then is gradually developing into the non-bonding prestressed reinforcement, the crack spacing and width have the same characteristics as the bonding reinforcement (both crack spacing and width are small), which is more conducive to enhance the durability of the structure.

  19. Laminae type and possible mechanisms for the formation of laminated sediments in the Shaban Deep, northern Red Sea

    Directory of Open Access Journals (Sweden)

    I. A. Seeberg-Elverfeldt

    2005-01-01

    Full Text Available Laminated sediments in the Shaban Deep, a brine-filled basin in the northern Red Sea, were analyzed with backscattered electron imagery. Here we present possible mechanisms involved in the formation of laminae of various types and homogenous intervals arising from the detailed investigation of multicore GeoB 7805-1 (26°13.9' N and 35°22.6' E; water depth 1447 m and gravity core GeoB 5836-2 (26°12.61' N, 35°21.56' E; water depth 1475 m. Sediment makeup includes six types: a a laminated structure with alternating light (mainly coccoliths and dark (diatom frustules layers, where the diatom component is indicative of the intra-annual variability between stratification and mixing events; b a pocket-like structure attributed to the sinking of particles within fecal pellets and aggregates; c a matrix of tightly packed diatoms that relates to extended stratification/mixing periods of the water column; d homogenous intervals that result from turbidity deposition; e silt accumulations which origin may lie in agglutinated foraminifers; and f pyrite layers with pyrite formation initiated at the seawater-brine interface.

  20. Antenatal Care Strengthening in Jimma, Ethiopia: A Mixed-Method Needs Assessment

    Directory of Open Access Journals (Sweden)

    Sarah Fredsted Villadsen

    2014-01-01

    Full Text Available Objective. We assessed how health system priorities matched user expectations and what the needs for antenatal care (ANC strengthening were for improved maternal health in Jimma, Ethiopia. Methods. A questionnaire survey among all recent mothers in the study area was conducted to study the content of ANC and to identify the predictors of low ANC satisfaction. Further, a qualitative approach was applied to understand perceptions, practices, and policies of ANC. Results. There were no national guidelines for ANC in Ethiopia. Within the health system, the teaching of health professional students was given high priority, and that contributed to a lack of continuity and privacy. To the women, poor user-provider interaction was a serious concern hindering the trust in the health care providers. Further, the care provision was compromised by the inadequate laboratory facilities, unstructured health education, and lack of training of health professionals. Conclusions. Health system trials are needed to study the feasibility of ANC strengthening in the study area. Nationally and internationally, the leadership needs to be strengthened with supportive supervision geared towards building trust and mutual respect to protect maternal and infant health.

  1. Shear Strengthening of RC Beams Using Sprayed Glass Fiber Reinforced Polymer

    Directory of Open Access Journals (Sweden)

    Sayed Mohamad Soleimani

    2012-01-01

    Full Text Available The effectiveness of externally bonded sprayed glass fiber reinforced polymer (Sprayed GFRP in shear strengthening of RC beams under quasi-static loading is investigated. Different techniques were utilized to enhance the bond between concrete and Sprayed GFRP, involving the use of through bolts and nuts paired with concrete surface preparation through sandblasting and through the use of a pneumatic chisel prior to Sprayed GFRP application. It was found that roughening the concrete surface using a pneumatic chisel and using through bolts and nuts were the most effective techniques. Also, Sprayed GFRP applied on 3 sides (U-shaped was found to be more effective than 2-sided Sprayed GFRP in shear strengthening. Sprayed GFRP increased the shear load-carrying capacity and energy absorption capacities of RC beams. It was found that the load-carrying capacity of strengthened RC beams was related to an effective strain of applied Sprayed GFRP. This strain was related to Sprayed GFRP configuration and the technique used to enhance the concrete-FRP bond. Finally, an equation was proposed to calculate the contribution of Sprayed GFRP in the shear strength of an RC beam.

  2. Mechanical and microstructural characterization of dispersion strengthened Al-C system nanocomposites

    International Nuclear Information System (INIS)

    Santos-Beltran, A.; Gallegos-Orozco, V.; Reyes, R. Goytia; Miki-Yoshida, M.; Estrada-Guel, I.; Martinez-Sanchez, R.

    2010-01-01

    Al and different amounts of C and C-Cu mixtures were used to produce Al-C and Al-C-Cu powder samples by mechanical milling. Microhardness tests were carried out to evaluate the mechanical properties of the nanocomposites in the as-milled condition. In general, the measured values were considerably higher than pure Al. In order to determine the causes of this hardening, the crystallite size and dislocation density were measured by means of X-ray analyses coupled with a convolutional multiple whole profile (CMWP) fitting program and a comparison with atomic force microscopy (AFM) observations. In Al-C samples, the hardening is mainly due to the decrease of the crystallite size, however for the Al-C-Cu, an additional strengthening mechanism appears and it seems that it is due by a dispersion of graphite nanoparticles in the Al matrix. The strengthening contributions of dislocation density, crystallite size and particle dispersion were modeled by superposing of every single contribution to strengthening (via hardness analyses). We found a direct relationship between the mechanical properties and the nominal amount of C-Cu, where Cu apparently acts as C nanoparticles integration and dispersion agent.

  3. Strengthening, modification and repair techniques’ prioritization for structural integrity control of ageing offshore structures

    International Nuclear Information System (INIS)

    Samarakoon, Samindi M.K.; Ratnayake, R.M. Chandima

    2015-01-01

    Structural integrity control is vital for existing ageing as well as newly built offshore and onshore structures. Structural integrity control becomes highly sensitive to interventions under a potential loss of structural integrity when it comes to offshore oil and gas production and process facilities. This is mainly due to the inherent constraints present in carrying out engineering work in the offshore atmosphere. It has been further exacerbated by the ageing offshore structures and the necessity of carrying out life extension toward the end of their design service lives. Local and international regulations demand the implementation of appropriate strengthening, modification and repair plans when significant changes in the structural integrity are revealed. In this context, strengthening, modification and repair techniques such as welding, member removal/reduction of loading, mechanical clamping and grouted repairs play a vital role. This manuscript presents an approach for prioritizing the strengthening, modification and repair techniques using a multi-criteria analysis approach. An analytic hierarchy process has been selected for the analysis via an illustrative case. It also provides a comprehensive overview of currently existing; strengthening, modification and repair techniques and their comparative pros and cons. - Highlights: • Structural integrity control (SIC) of ageing and intact offshore structures. • Strengthening, modification and/or repair (SMR) techniques have been explained. • Application of multi-criteria analysis conserving SI has been illustrated. • SMR techniques prioritization and sensitivity analysis has been performed

  4. The role of CD103+ Dendritic cells in the intestinal mucosal immune system.

    Directory of Open Access Journals (Sweden)

    Darren Thomas Ruane

    2011-07-01

    Full Text Available While dendritic cells (DC are central to the induction and regulation of adaptive immunity, these cells are very heterogenous and specific subsets can be characterized based on the expression of cell surface markers and functional properties. Intestinal CD103+ DCs are the subject of particular interest due to their role in regulating mucosal immunity. Since the epithelial surfaces are constantly exposed to a high antigenic load, tight regulation of innate and adaptive intestinal immune responses is vital as intestinal inflammation can have detrimental consequences for the host. Strategically positioned within the lamina propria, CD103+ DCs play an important role in maintaining intestinal immune homeostasis. These cells are required for the induction of tolerogenic immune responses and imprinting gut homing phenotypic changes on antigen-specific T cells. Recent insights into their development and regulatory properties have revealed additional immunoregulatory roles and further highlighted their importance for intestinal immunity. In this review we discuss the nature of the intestinal CD103+ DC population and the emerging roles of these cells in the regulation of mucosal immunity.

  5. Self-diagnosis of structures strengthened with hybrid carbon-fiber-reinforced polymer sheets

    Science.gov (United States)

    Wu, Z. S.; Yang, C. Q.; Harada, T.; Ye, L. P.

    2005-06-01

    The correlation of mechanical and electrical properties of concrete beams strengthened with hybrid carbon-fiber-reinforced polymer (HCFRP) sheets is studied in this paper. Two types of concrete beams, with and without reinforcing bars, are strengthened with externally bonded HCFRP sheets, which have a self-structural health monitoring function due to the electrical conduction and piezoresistivity of carbon fibers. Parameters investigated include the volume fractions and types of carbon fibers. According to the investigation, it is found that the hybridization of uniaxial HCFRP sheets with several different types of carbon fibers is a viable method for enhancing the mechanical properties and obtaining a built-in damage detection function for concrete structures. The changes in electrical resistance during low strain ranges before the rupture of carbon fibers are generally smaller than 1%. Nevertheless, after the gradual ruptures of carbon fibers, the electrical resistance increases remarkably with the strain in a step-wise manner. For the specimens without reinforcing bars, the electrical behaviors are not stable, especially during the low strain ranges. However, the electrical behaviors of the specimens with reinforcing bars are relatively stable, and the whole range of self-sensing function of the HCFRP-strengthened RC structures has realized the conceptual design of the HCFRP sensing models and is confirmed by the experimental investigations. The relationships between the strain/load and the change in electrical resistance show the potential self-monitoring capacity of HCFRP reinforcements used for strengthening concrete structures.

  6. Programs for Strengthening Families of State Prison Staff

    Science.gov (United States)

    Tripp, Paula J.

    2010-01-01

    This article describes "Training for Strong Families," a family strengthening program for officers working in the state prison system. The program was offered once per week on the same day and at the same time, and the sessions lasted 15-20 minutes. The new program included topics such as Budgeting 101, Relationships, and Stress Management.…

  7. Strengthening Rural Livelihoods : The Impact of Information and ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    20 sept. 2011 ... Strengthening Rural Livelihoods dresse un bilan utile et équilibré de l'influence que les téléphones mobiles et Internet peuvent avoir sur le soutien des moyens de subsistance des populations rurales, et notamment des agriculteurs en Asie. Tim Unwin, titulaire de la chaire UNESCO en TIC pour le ...

  8. Cracking of Beams Strengthened with Externally Bonded SRP Tapes

    Science.gov (United States)

    Krzywoń, Rafał

    2017-10-01

    Paper discusses strengthening efficiency of relatively new kind of SRP composite based on high strength steel wires. They are made of ultra-high strength steel primarily used in cords of car tires. Through advanced treatment, the mechanical properties of SRP steel are similar to other high carbon cold drawn steels used in construction industry. Strength significantly exceed 2000 MPa, there is no perfect plasticity at yield stress level. Almost linear stress-strain relationship makes SRP steel mechanical properties similar to carbon fibers. Also flexibility and weight ratio of the composite overlay is slightly worse than CFRP strip. Despite these advantages SRP is not as popular as other composites reinforced with fibers of high strength. This is due to the small number of studies of SRP behavior and applicability. Paper shows selected results of the laboratory test of beams strengthened with use of SRP and CFRP externally bonded overlays. Attention has been focused primarily on the phenomenon of cracking. Comparison include the cracking moment, crack width and spacing, coverage of crack zone. Despite the somewhat lower rigidity of SRP tapes, they have a much better adhesion to concrete, so that the crack width is comparable in almost the whole load range. The paper also includes an assessment of the common methods of checking the condition of cracking in relation to the tested SRP strengthening. The paper presents actual calculation procedures to determine the crack spacing and crack width. The discussed formulas are verified with results of provided laboratory tests.

  9. Cognitive health benefits of strengthening exercise for community-dwelling older adults.

    Science.gov (United States)

    Anderson-Hanley, Cay; Nimon, Joseph P; Westen, Sarah C

    2010-11-01

    While aerobic exercise has been linked to improved performance on cognitive tasks of executive functioning among older adults, not all older adults can avail themselves of such exercise due to physical limitations. In this study, community-dwelling older adults were evaluated on tasks of executive functioning before and after a month-long strengthening, nonaerobic exercise program. A total of 16 participants who engaged in such exercise showed significantly improved scores on Digits Backward and Stroop C tasks when compared to 16 participants who were on an exercise waiting list. Positive benefits of strengthening exercise on cognition are supported. Additional research is needed to clarify the generalizability of these findings.

  10. Effect of eccentric isokinetic strengthening in the rehabilitation of patients with knee osteoarthritis: Isogo, a randomized trial

    Science.gov (United States)

    2014-01-01

    Background Femorotibial knee osteoarthritis is associated with muscle weakness in the lower limbs, particularly in the quadriceps, which results in disease progression. The interest of having muscular strengthening as part of the therapeutic arsenal for the medical treatment of knee osteoarthritis is now well established. The functional disability induced by knee osteoarthritis manifests itself principally when walking, notably downhill, during which the muscles are called upon to contract eccentrically. We can therefore think that eccentric muscular strengthening could bring a functional benefit that is superior to concentric muscular strengthening. Methods/Design This is a prospective, randomized, bicenter, parallel-group, international study. Eighty patients aged from 40 to 75 years old, suffering from medical-stage knee osteoarthritis, will undertake 6 weeks of isokinetic muscular strengthening. Randomization determines the mode of muscular strengthening: either exclusively eccentric or exclusively concentric. The principal objective is to demonstrate the superiority of the improvement in the quadriceps isokinetic torque after isokinetic muscular strengthening by the eccentric mode compared to the concentric mode. The following parameters are also evaluated: the variations in the level of pain, the parameters of walking (maximum speed over 10 and 200 meters, analysis on a computerized Gaitrite™ treadmill), static equilibrium (on a FUSYO™ force platform), and the functional status of the patient using the Western Ontario and MacMaster Universities osteoarthritis index (WOMAC) questionnaire after the strengthening period and at 6 months. Discussion A better knowledge of the most effective mode of muscular strengthening is needed to optimize the functional benefits to the patients. In case of superiority in terms of efficacy of the eccentric mode, the latter could be given priority in the rehabilitation treatment of knee osteoarthritis patients. Trial

  11. Neural organization of first optic neuropils in the littoral crab Hemigrapsus oregonensis and the semiterrestrial species Chasmagnathus granulatus.

    Science.gov (United States)

    Sztarker, Julieta; Strausfeld, Nicholas; Andrew, David; Tomsic, Daniel

    2009-03-10

    Crustaceans are among the most extensively distributed arthropods, occupying many ecologies and manifesting a great variety of compound eye optics; but in comparison with insects, relatively little is known about the organization and neuronal morphologies of their underlying optic neuropils. Most studies, which have been limited to descriptions of the first neuropil--the lamina--suggest that different species have approximately comparable cell types. However, such studies have been limited with regard to the types of neurons they identify and most omit their topographic relationships. It is also uncertain whether similarities, such as they are, are independent of visual ecologies. The present account describes and compares the morphologies and dispositions of monopolar and other efferent neurons as well as the organization of tangential and smaller centrifugal neurons in two grapsoid crabs, one from the South Atlantic, the other from the North Pacific. Because these species occupy significantly disparate ecologies we ask whether this might be reflected in differences of cell arrangements within the most peripheral levels of the visual system. The present study identifies such differences with respect to the organization of centrifugal neurons to the lamina. We also identify in both species neurons in the lamina that have hitherto not been identified in crustaceans and we draw specific comparisons between the layered organization of the grapsoid lamina and layered laminas of insects.

  12. Elements for harnessing participatory action research to strengthen health managers' capacity: a critical interpretative synthesis.

    Science.gov (United States)

    Tetui, Moses; Zulu, Joseph Mumba; Hurtig, Anna-Karin; Ekirapa-Kiracho, Elizabeth; Kiwanuka, Suzanne N; Coe, Anna-Britt

    2018-04-19

    Health managers play a key role in ensuring that health services are responsive to the needs of the population. Participatory action research (PAR) is one of the approaches that have been used to strengthen managers' capacity. However, collated knowledge on elements for harnessing PAR to strengthen managers' capacity is missing. This paper bridges this gap by reviewing existing literature on the subject matter. A critical interpretive synthesis method was used to interrogate eight selected articles. These articles reported the use of PAR to strengthen health managers' capacity. The critical interpretive synthesis method's approach to analysis guided the synthesis. Here, the authors interpretively made connections and linkages between different elements identified in the literature. Finally, the Atun et al. (Heal Pol Plann, 25:104-111, 2010) framework on integration was used to model the elements synthesised in the literature into five main domains. Five elements with intricate bi-directional interactions were identified in the literature reviewed. These included a shared purpose, skilled facilitation and psychological safety, activity integration into organisational procedures, organisational support, and external supportive monitoring. A shared purpose of the managers' capacity strengthening initiative created commitment and motivation to learn. This purpose was built upon a set of facilitation skills that included promoting participation, self-efficacy and reflection, thereby creating a safe psychological space within which the managers interacted and learnt from each other and their actions. Additionally, an integrated intervention strengthened local capacity and harnessed organisational support for learning. Finally, supportive monitoring from external partners, such as researchers, ensured quality, building of local capacity and professional safety networks essential for continued learning. The five elements identified in this synthesis provide a basis upon

  13. ONE OF THE POSSIBLE WAYS TO STRENGTHENING THE SECURITY

    Directory of Open Access Journals (Sweden)

    Roman URBAN

    2016-09-01

    Full Text Available The paper is intended to point out at the relation between security and its key vehicle that is humans themselves. It presents an option to strengthen security through purposeful education of peiple and their comprehensive training in peaceful settlement of conflicts.

  14. "Strengthening" Ontario Universities: A Neoliberal Reconstruction of Higher Education

    Science.gov (United States)

    Rigas, Bob; Kuchapski, Renée

    2016-01-01

    This paper reviews neoliberalism as an ideology that has influenced higher education generally and Ontario higher education in particular. It includes a discourse analysis of "Strengthening Ontario's Centres of Creativity, Innovation and Knowledge" (Ontario Ministry of Training, Colleges, and Universities, 2012), a government discussion…

  15. Functions of innate immune cells and commensal bacteria in gut homeostasis.

    Science.gov (United States)

    Kayama, Hisako; Takeda, Kiyoshi

    2016-02-01

    The intestinal immune system remains unresponsive to beneficial microbes and dietary antigens while activating pro-inflammatory responses against pathogens for host defence. In intestinal mucosa, abnormal activation of innate immunity, which directs adaptive immune responses, causes the onset and/or progression of inflammatory bowel diseases. Thus, innate immunity is finely regulated in the gut. Multiple innate immune cell subsets have been identified in both murine and human intestinal lamina propria. Some innate immune cells play a key role in the maintenance of gut homeostasis by preventing inappropriate adaptive immune responses while others are associated with the pathogenesis of intestinal inflammation through development of Th1 and Th17 cells. In addition, intestinal microbiota and their metabolites contribute to the regulation of innate/adaptive immune responses. Accordingly, perturbation of microbiota composition can trigger intestinal inflammation by driving inappropriate immune responses. © The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

  16. Interfacial stresses in strengthened beam with shear cohesive zone ...

    Indian Academy of Sciences (India)

    The results of parametric study are compared with those of Smith and Teng. They confirm the accuracy of the proposed approach in predicting both interfacial shear and normal stresses. Keywords. Strengthened beam; interfacial stresses; cohesive zone; shear deformation. 1. Introduction. The FRP plates can be either ...

  17. Grain boundary precipitation strengthening mechanism in W containing advanced creep resistant ferritic steels

    Energy Technology Data Exchange (ETDEWEB)

    Shibata, T.; Hasegawa, Y. [Tohoku Univ., Sendai (Japan)

    2010-07-01

    Grain boundary precipitation strengthening is expected to be a decisive factor in developing ferritic creep resistant steels. This study examined the grain boundary precipitation strengthening mechanism extracting the effect of the tempered martensitic microstructure and precipitates on the high angle grain boundary in M{sub 23}C4{sub 6} type carbide and the Fe{sub 2}W type Laves phase effect of the creep deformation fixing the grain boundary according to transmission electron microscope (TEM) observation. A creep test was carried out at high temperature in order to evaluate the high angle boundary strengthening effect simulating the long-term creep deformation microstructure by the lath structure disappearance. The correlation of the creep rupture time and the grain boundary shielding ratio were found to be independent of precipitate type. The creep deformation model represents block boundary shielding by precipitates as the decisive factor for W containing ferritic creep resistant steels. (orig.)

  18. Applying principles of health system strengthening to eye care

    Directory of Open Access Journals (Sweden)

    Karl Blanchet

    2012-01-01

    Full Text Available Understanding Health systems have now become the priority focus of researchers and policy makers, who have progressively moved away from a project-centred perspectives. The new tendency is to facilitate a convergence between health system developers and disease-specific programme managers in terms of both thinking and action, and to reconcile both approaches: one focusing on integrated health systems and improving the health status of the population and the other aiming at improving access to health care. Eye care interventions particularly in developing countries have generally been vertically implemented (e.g. trachoma, cataract surgeries often with parallel organizational structures or specialised disease specific services. With the emergence of health system strengthening in health strategies and in the service delivery of interventions there is a need to clarify and examine inputs in terms governance, financing and management. This present paper aims to clarify key concepts in health system strengthening and describe the various components of the framework as applied in eye care interventions.

  19. Reduced satellite cell number in situ in muscular contractures from children with cerebral palsy.

    Science.gov (United States)

    Dayanidhi, Sudarshan; Dykstra, Peter B; Lyubasyuk, Vera; McKay, Bryon R; Chambers, Henry G; Lieber, Richard L

    2015-07-01

    Satellite cells (SC) are quiescent adult muscle stem cells critical for postnatal development. Children with cerebral palsy have impaired muscular growth and develop contractures. While flow cytometry previously demonstrated a reduced SC population, extracellular matrix abnormalities may influence the cell isolation methods used, systematically isolating fewer cells from CP muscle and creating a biased result. Consequently, the purpose of this study was to use immunohistochemistry on serial muscle sections to quantify SC in situ. Serial cross-sections from human gracilis muscle biopsies (n = 11) were labeled with fluorescent antibodies for Pax7 (SC transcriptional marker), laminin (basal lamina), and 4',6-diamidino-2-phenylindole (nuclei). Fluorescence microscopy under high magnification was used to identify SC based on labeling and location. Mean SC/100 myofibers was reduced by ∼70% (p muscle growth and apparent decreased responsiveness of CP muscle to exercise. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  20. [Sex differences in neuromodulation of mucosal mast cells in the rat jejunum].

    Science.gov (United States)

    Gottwald, T; Becker, H D; Stead, R H

    1997-01-01

    The effect of electrical stimulation of both cervical vagal nerves on mucosal mast cells in the jejunum was investigated in an in vivo animal model with rats of both sexes. Males showed a significant increase of mast cell densities after electrical stimulation (1.0 mA, 5 Hz, 5 ms, 12 min) in the lamina propria. Simultaneously, we observed a significant increase of tissue histamine levels (ANOVA: P < 0.05), whereas serum levels remained unchanged. However, even though females had significantly higher levels throughout compared to males (ANOVA: P < 0.05), they did not show any significant reaction to electrical stimulation. These in vivo data support morphological and in vitro data from other investigators, who hypothesized a functional interaction between mucosal mast cells and nerves. However, degranulation seems to be a poor in situ indicator for mast-cell stimulation, as mast-cell densities increased in males, while the percentage of degranulated cells remained the same in all groups (about 40%). Instead, electrical stimulation of the vagal nerve seems to trigger histamine synthesis, or simply stabilization of mast cells. Interestingly, this phenomenon seems to be sex-dependent, suggesting a regulatory role for sex hormones in this scenario.