Science.gov

Sample records for form scar-like perivascular

  1. Olfactory ensheathing cell-neurite alignment enhances neurite outgrowth in scar-like cultures

    PubMed Central

    Khankan, Rana R.; Wanner, Ina B.; Phelps, Patricia E.

    2015-01-01

    The regenerative capacity of the adult CNS neurons after injury is strongly inhibited by the spinal cord lesion site environment that is composed primarily of the reactive astroglial scar and invading meningeal fibroblasts. Olfactory ensheathing cell (OEC) transplantation facilitates neuronal survival and functional recovery after a complete spinal cord transection, yet the mechanisms by which this recovery occurs remain unclear. We used a unique multicellular scar-like culture model to test if OECs promote neurite outgrowth in growth inhibitory areas. Astrocytes were mechanically injured and challenged by meningeal fibroblasts to produce key inhibitory elements of a spinal cord lesion. Neurite outgrowth of postnatal cerebral cortical neurons was assessed on three substrates: quiescent astrocyte control cultures, reactive astrocyte scar-like cultures, and scar-like cultures with OECs. Initial results showed that OECs enhanced total neurite outgrowth of cortical neurons in a scar-like environment by 60%. We then asked if the neurite growth-promoting properties of OECs depended on direct alignment between neuronal and OEC processes. Neurites that aligned with OECs were nearly three times longer when they grew on inhibitory meningeal fibroblast areas and twice as long on reactive astrocyte zones compared to neurites not associated with OECs. Our results show that OECs can independently enhance neurite elongation and that direct OEC-neurite cell contact can provide a permissive substrate that overcomes the inhibitory nature of the reactive astrocyte scar border and the fibroblast-rich spinal cord lesion core. PMID:25863021

  2. Perivascular cells for regenerative medicine

    PubMed Central

    Crisan, Mihaela; Corselli, Mirko; Chen, William CW; Péault, Bruno; Moldovan, NI

    2012-01-01

    Mesenchymal stem/stromal cells (MSC) are currently the best candidate therapeutic cells for regenerative medicine related to osteoarticular, muscular, vascular and inflammatory diseases, although these cells remain heterogeneous and necessitate a better biological characterization. We and others recently described that MSC originate from two types of perivascular cells, namely pericytes and adventitial cells and contain the in situ counterpart of MSC in developing and adult human organs, which can be prospectively purified using well defined cell surface markers. Pericytes encircle endothelial cells of capillaries and microvessels and express the adhesion molecule CD146 and the PDGFRβ, but lack endothelial and haematopoietic markers such as CD34, CD31, vWF (von Willebrand factor), the ligand for Ulex europaeus 1 (UEA1) and CD45 respectively. The proteoglycan NG2 is a pericyte marker exclusively associated with the arterial system. Besides its expression in smooth muscle cells, smooth muscle actin (αSMA) is also detected in subsets of pericytes. Adventitial cells surround the largest vessels and, opposite to pericytes, are not closely associated to endothelial cells. Adventitial cells express CD34 and lack αSMA and all endothelial and haematopoietic cell markers, as for pericytes. Altogether, pericytes and adventitial perivascular cells express in situ and in culture markers of MSC and display capacities to differentiate towards osteogenic, adipogenic and chondrogenic cell lineages. Importantly, adventitial cells can differentiate into pericyte-like cells under inductive conditions in vitro. Altogether, using purified perivascular cells instead of MSC may bring higher benefits to regenerative medicine, including the possibility, for the first time, to use these cells uncultured. PMID:22882758

  3. EARLY SENESCENCE1 Encodes a SCAR-LIKE PROTEIN2 That Affects Water Loss in Rice1[OPEN

    PubMed Central

    Rao, Yuchun; Yang, Yaolong; Xu, Jie; Li, Xiaojing; Leng, Yujia; Dai, Liping; Huang, Lichao; Shao, Guosheng; Ren, Deyong; Hu, Jiang; Guo, Longbiao; Pan, Jianwei; Zeng, Dali

    2015-01-01

    The global problem of drought threatens agricultural production and constrains the development of sustainable agricultural practices. In plants, excessive water loss causes drought stress and induces early senescence. In this study, we isolated a rice (Oryza sativa) mutant, designated as early senescence1 (es1), which exhibits early leaf senescence. The es1-1 leaves undergo water loss at the seedling stage (as reflected by whitening of the leaf margin and wilting) and display early senescence at the three-leaf stage. We used map-based cloning to identify ES1, which encodes a SCAR-LIKE PROTEIN2, a component of the suppressor of cAMP receptor/Wiskott-Aldrich syndrome protein family verprolin-homologous complex involved in actin polymerization and function. The es1-1 mutants exhibited significantly higher stomatal density. This resulted in excessive water loss and accelerated water flow in es1-1, also enhancing the water absorption capacity of the roots and the water transport capacity of the stems as well as promoting the in vivo enrichment of metal ions cotransported with water. The expression of ES1 is higher in the leaves and leaf sheaths than in other tissues, consistent with its role in controlling water loss from leaves. GREEN FLUORESCENT PROTEIN-ES1 fusion proteins were ubiquitously distributed in the cytoplasm of plant cells. Collectively, our data suggest that ES1 is important for regulating water loss in rice. PMID:26243619

  4. Intracerebral hematoma extends via perivascular spaces and perineurium.

    PubMed

    Yin, Jia; Lü, Tian-Ming; Qiu, Guang; Huang, Rui-Yu; Fang, Min; Wang, Yuan-Yuan; Xiao, Duan; Liu, Xiao-Jia

    2013-01-01

    Intracerebral hemorrhage (ICH) is a devastating disorder associated with high morbidity and mortality. ICH results in the formation of hematoma that affects not only the primary site of injury but also the remote regions. In fact, hematoma can extend via perivascular spaces (also called Virchow-Robin spaces, VRS) and perineurium in an animal model of ICH. In the present study, we used magnetic resonance imaging (MRI) with susceptibility-weighted imaging (SWI) to investigate the characteristics of the perivascular and perineural extensions of hematomas in patients with ICH. A total of 20 ICH patients without secondary subarachnoid and secondary intraventricular hemorrhages were recruited. Brain MRI scans, including SWI, T1, and T2-weighted images, were performed between 17 h to 7 days after the onset of ICH. MRI with SWI revealed that paramagnetic substances spread along the VRS or the perineurium. Such distribution could cause the formation of cerebral microbleeds (CMBs). However, the distribution of remote hemorrhagic lesions varied, depending on the size and location of the original hematoma. The unenhanced CT scans of the 20 patients did not show any hyperdensity around the blood vessels and nerve tracts outside the hematoma. These results indicate the perivascular and perineural extensions of hematomas in patients with ICH, which is formed by the leakage of the original hematoma via the VRS or perineurium. We also provide a new explanation for the series of pathological processes involved in ICH, including the remote effects of hematoma and the formation of CMBs in patients with ICH. PMID:23812162

  5. Changes in the population of perivascular cells in the bone tissue remodeling zones under microgravity

    NASA Astrophysics Data System (ADS)

    Katkova, Olena; Rodionova, Natalia; Shevel, Ivan

    2016-07-01

    Microgravity and long-term hypokinesia induce reduction both in bone mass and mineral saturation, which can lead to the development of osteoporosis and osteopenia. (Oganov, 2003). Reorganizations and adaptive remodeling processes in the skeleton bones occur in the topographical interconnection with blood capillaries and perivascular cells. Radioautographic studies with 3H- thymidine (Kimmel, Fee, 1980; Rodionova, 1989, 2006) have shown that in osteogenesis zones there is sequential differentiation process of the perivascular cells into osteogenic. Hence the study of populations of perivascular stromal cells in areas of destructive changes is actual. Perivascular cells from metaphysis of the rat femoral bones under conditions of modeling microgravity were studied using electron microscopy and cytochemistry (hindlimb unloading, 28 days duration) and biosatellite «Bion-M1» (duration of flight from April 19 till May 19, 2013 on C57, black mice). It was revealed that both control and test groups populations of the perivascular cells are not homogeneous in remodeling adaptive zones. These populations comprise of adjacent to endothelium poorly differentiated forms and isolated cells with signs of differentiation (specific increased volume of rough endoplasmic reticulum in cytoplasm). Majority of the perivascular cells in the control group (modeling microgravity) reveals reaction to alkaline phosphatase (marker of the osteogenic differentiation). In poorly differentiated cells this reaction is registered in nucleolus, nucleous and cytoplasm. In differentiating cells activity of the alkaline phosphatase is also detected on the outer surface of the cellular membrane. Unlike the control group in the bones of experimental animals reaction to the alkaline phosphatase is registered not in all cells of perivascular population. Part of the differentiating perivascular cells does not contain a product of the reaction. Under microgravity some poorly differentiated perivascular

  6. Differentiation potentials of perivascular cells in the bone tissue remodeling zones under microgravity

    NASA Astrophysics Data System (ADS)

    Rodionova, Natalia; Katkova, Olena

    Adaptive remodeling processes in the skeleton bones occur in the close topographical interconnection with blood capillaries followed by perivascular cells. Radioautographic studies with 3Н- thymidine (Kimmel D.B., Fee W.S., 1980; Rodionova N.V., 1989, 2006) has shown that in osteogenesis zones there is sequential differentiation process of the perivascular cells into osteogenic ones. Using electron microscopy and cytochemistry we studied perivsacular cells in metaphysis of the rats femoral bones under conditions of modeling microgravity (28 days duration) and in femoral bonеs metaphyses of rats flown on board of the space laboratory (Spacelab - 2) It was revealed that population of the perivascular cells is not homogeneous in adaptive zones of the remodeling in both control and test groups (lowering support loading). This population comprises adjacent to endothelium little differentiated forms and isolated cells with differentiation features (specific volume of rough endoplasmic reticulum in cytoplasm is increased). Majority of the perivascular cells in the control group reveals reaction to alkaline phosphatase (marker of the osteogenic differentiation). In little differentiated cells this reaction is registered in nucleolus, nucleous and cytoplasm. In differentiating cells activity of the alkaline phosphatase is also detected on the outer surface of the cellular membrane. Unlike the control group in the bones of animals under microgravitaty reaction to the alkaline phosphatase is registered not for all cells of perivascular population. Part of the differentiating perivascular cells does not contain a product of the reaction. There is also visible trend of individual alkaline phosphatase containing perivascular cells amounts decrease (i.e. osteogenic cells-precursors). Under microgravity some little differentiated perivascular cells reveal destruction signs. Found decrease trend of the alkaline phosphatase containing cells (i.e. osteogenic cells) number in

  7. Spontaneous Regression and Recurrence of a Tumefactive Perivascular Space

    PubMed Central

    Muttikkal, Thomas Jose Eluvathingal; Raghavan, Prashant

    2014-01-01

    Summary Perivascular spaces can occasionally appear mass-like (tumefactive or giant perivascular space), and can be associated with clinical symptoms. Spontaneous regression of a tumefactive perivascular space is a very rare phenomenon with only two reported cases in the English medical literature. Spontaneous regression of a tumefactive perivascular space along with resolution of clinical symptoms, followed by spontaneous recurrence associated with symptom recurrence is an extremely rare occurrence, which to the best of our knowledge, has not been reported in the medical literature. We describe a case of spontaneous regression of a tumefactive perivascular space, three years after its initial detection, followed by spontaneous recurrence after two years. PMID:24750709

  8. CD163 Identifies Perivascular Macrophages in Normal and Viral Encephalitic Brains and Potential Precursors to Perivascular Macrophages in Blood

    PubMed Central

    Kim, Woong-Ki; Alvarez, Xavier; Fisher, Jeanne; Bronfin, Benjamin; Westmoreland, Susan; McLaurin, JoAnne; Williams, Kenneth

    2006-01-01

    Perivascular macrophages are uniquely situated at the intersection between the nervous and immune systems. Although combined myeloid marker detection differentiates perivascular from resident brain macrophages (parenchymal microglia), no single marker distinguishes perivascular macrophages in humans and mice. Here, we present the macrophage scavenger receptor CD163 as a marker for perivascular macrophages in humans, monkeys, and mice. CD163 was primarily confined to perivascular macrophages and populations of meningeal and choroid plexus macrophages in normal brains and in brains of humans and monkeys with human immunodeficiency virus or simian immunodeficiency virus (SIV) encephalitis. Scattered microglia in SIV encephalitis lesions and multinucleated giant cells were also CD163 positive. Consistent with prior findings that perivascular macrophages are primary targets of human immunodeficiency virus and SIV, all SIV-infected cells in the brain were CD163 positive. Using fluorescent dyes that definitively and selectively label perivascular macrophages in vivo, we confirmed that dye-labeled simian perivascular macrophages were CD163 positive and able to repopulate the central nervous system within 24 hours. Flow cytometric studies demonstrated a subset of monocytes (CD163+CD14+CD16+) that were immunophenotypically similar to brain perivascular macrophages. These findings recognize CD163+ blood monocytes/macrophages as a source of brain perivascular macrophages and underscore the utility of this molecule in studying the biology of perivascular macrophages and their precursors in humans, monkeys, and mice. PMID:16507898

  9. Fluid mechanics in the perivascular space.

    PubMed

    Wang, Peng; Olbricht, William L

    2011-04-01

    Perivascular space (PVS) within the brain is an important pathway for interstitial fluid (ISF) and solute transport. Fluid flowing in the PVS can affect these transport processes and has significant impacts on physiology. In this paper, we carry out a theoretical analysis to investigate the fluid mechanics in the PVS. With certain assumptions and approximations, we are able to find an analytical solution to the problem. We discuss the physical meanings of the solution and particularly examine the consequences of the induced fluid flow in the context of convection-enhanced delivery (CED). We conclude that peristaltic motions of the blood vessel walls can facilitate fluid and solute transport in the PVS.

  10. Nerve growth factor facilitates perivascular innervation in neovasculatures of mice.

    PubMed

    Goda, Mitsuhiro; Takatori, Shingo; Atagi, Saori; Hashikawa-Hobara, Narumi; Kawasaki, Hiromu

    2016-08-01

    It is well known that blood vessels including arterioles have a perivascular innervation. It is also widely accepted that perivascular nerves maintain vascular tone and regulate blood flow. Although there are currently prevailing opinions, unified views on the innervation of microcirculation in any organs have not been established. The present study was designed to investigate whether there are perivascular nerves innervated in microvessels and neovessels. Furthermore, we examined whether nerve growth factor (NGF) can exert a promotional effect on perivascular nerve innervation in neovessels of Matrigel plugs. A Matrigel was subcutaneously implanted in mouse. The presence of perivascular nerves in Matrigel on Day 7-21 after the implantation was immunohistochemically studied. NGF or saline was subcutaneously administered by an osmotic mini-pump for a period of 3-14 days. The immunostaining of neovasculatures in Matrigel showed the presence of perivascular nerves on Day 21 after Matrigel injection. Perivascular nerve innervation of neovessels within Matrigel implanted in NGF-treated mice was observed in Day 17 after Matrigel implantation. However, NGF treatment did not increase numbers of neovessels in Matrigel. These results suggest that perivascular nerves innervate neovessels as neovasculatures mature and that NGF accelerates the innervation of perivascular nerves in neovessels. PMID:27493098

  11. How do culture media influence in vitro perivascular cell behavior?

    PubMed

    Huber, Birgit; Volz, Ann-Cathrin; Kluger, Petra Juliane

    2015-12-01

    Perivascular cells are multilineage cells located around the vessel wall and important for wall stabilization. In this study, we evaluated a stem cell media and a perivascular cell-specific media for the culture of primary perivascular cells regarding their cell morphology, doubling time, stem cell properties, and expression of cell type-specific markers. When the two cell culture media were compared to each other, perivascular cells cultured in the stem cell medium had a more elongated morphology and a faster doubling rate and cells cultured in the pericyte medium had a more typical morphology, with several filopodia, and a slower doubling rate. To evaluate stem cell properties, perivascular cells, CD146(-) cells, and mesenchymal stem cells (MSCs) were differentiated into the adipogenic, osteogenic, and chondrogenic lineages. It was seen that perivascular cells, as well as CD146(-) cells and MSCs, cultured in stem cell medium showed greater differentiation than cells cultured in pericyte-specific medium. The expression of pericyte-specific markers CD146, neural/glial antigen 2 (NG2), platelet-derived growth factor receptor-β (PDGFR-β), myosin, and α-smooth muscle actin (α-SMA) could be found in both pericyte cultures, as well as to varying amounts in CD146(-) cells, MSCs, and endothelial cells. The here presented work shows that perivascular cells can adapt to their in vitro environment and cell culture conditions influence cell functionality, such as doubling rate or differentiation behavior. Pericyte-specific markers were shown to be expressed also from cells other than perivascular cells. We can further conclude that CD146(+) perivascular cells are inhomogeneous cell population probably containing stem cell subpopulations, which are located perivascular around capillaries.

  12. How do culture media influence in vitro perivascular cell behavior?

    PubMed

    Huber, Birgit; Volz, Ann-Cathrin; Kluger, Petra Juliane

    2015-12-01

    Perivascular cells are multilineage cells located around the vessel wall and important for wall stabilization. In this study, we evaluated a stem cell media and a perivascular cell-specific media for the culture of primary perivascular cells regarding their cell morphology, doubling time, stem cell properties, and expression of cell type-specific markers. When the two cell culture media were compared to each other, perivascular cells cultured in the stem cell medium had a more elongated morphology and a faster doubling rate and cells cultured in the pericyte medium had a more typical morphology, with several filopodia, and a slower doubling rate. To evaluate stem cell properties, perivascular cells, CD146(-) cells, and mesenchymal stem cells (MSCs) were differentiated into the adipogenic, osteogenic, and chondrogenic lineages. It was seen that perivascular cells, as well as CD146(-) cells and MSCs, cultured in stem cell medium showed greater differentiation than cells cultured in pericyte-specific medium. The expression of pericyte-specific markers CD146, neural/glial antigen 2 (NG2), platelet-derived growth factor receptor-β (PDGFR-β), myosin, and α-smooth muscle actin (α-SMA) could be found in both pericyte cultures, as well as to varying amounts in CD146(-) cells, MSCs, and endothelial cells. The here presented work shows that perivascular cells can adapt to their in vitro environment and cell culture conditions influence cell functionality, such as doubling rate or differentiation behavior. Pericyte-specific markers were shown to be expressed also from cells other than perivascular cells. We can further conclude that CD146(+) perivascular cells are inhomogeneous cell population probably containing stem cell subpopulations, which are located perivascular around capillaries. PMID:26179857

  13. A distinct histopathological variant of a malignant melanoma with perivascular pseudorosettes: A case report.

    PubMed

    Ishida, Mitsuaki; Iwai, Muneo; Yoshida, Keiko; Kagotani, Akiko; Okabe, Hidetoshi

    2013-09-01

    Although a rare condition, rosette formation in malignant melanoma has been previously documented. The present study describes the second documented case of malignant melanoma with perivascular pseudorosettes. A 38-year-old male presented with a black nodule on his back. Histopathological study revealed diffuse proliferation of neoplastic cells in the dermis and subcutis. A section of the tumor (~30%) was composed of a conventional malignant melanoma component. The remaining area was comprised of medium-sized polygonal cells with slightly eosinophilic cytoplasm and small-to-medium, round nuclei. Melanin pigment was rarely observed. A noteworthy observation was the presence of perivascular pseudorosette formations, which were characterized by their radial arrangement around the blood vessels, with a perivascular, anuclear zone. Immunohistochemically, the neoplastic cells were diffusely positive for S-100 protein and Melan-A and focally positive for HMB-45. Clinicopathological analyses of cases of malignant melanoma with rosette formations revealed that the types of rosette included the Homer-Wright type (two cases), perivascular pseudorosettes (two cases) and an unclassifiable type (one case). Immunohistochemical analysis is a useful method for forming a diagnosis as Melan-A or HMB-45 are generally expressed in all cases. Rosette formation in malignant melanoma is a distinct histopathological variant and may be an under-recognized phenomenon. Therefore, its recognition is significant for obtaining an accurate diagnosis of malignant melanoma.

  14. Perivascular macrophages mediate neutrophil recruitment during bacterial skin infection

    PubMed Central

    Abtin, Arby; Jain, Rohit; Mitchell, Andrew J.; Roediger, Ben; Brzoska, Anthony J.; Tikoo, Shweta; Cheng, Qiang; Ng, Lai Guan; Cavanagh, Lois L.; von Andrian, Ulrich H.; Hickey, Michael J.; Firth, Neville; Weninger, Wolfgang

    2014-01-01

    Transendothelial migration of neutrophils in post-capillary venules is a key event in the inflammatory response against pathogens and tissue damage. The precise regulation of this process is incompletely understood. We report that perivascular macrophages are critical for neutrophil migration into skin infected with the pathogen Staphylococcus aureus. Using multiphoton intravital microscopy we show that neutrophils extravasate from inflamed dermal venules in close proximity to perivascular macrophages, which are a major source of neutrophil chemoattractants. The virulence factor alpha-hemolysin lyses perivascular macrophages leading to decreased neutrophil transmigration. Our data illustrate a previously unrecognized role for perivascular macrophages in neutrophil recruitment to inflamed skin, and indicate that Staphylococcus aureus uses hemolysin-dependent killing of these cells as an immune evasion strategy. PMID:24270515

  15. Perivascular macrophages mediate neutrophil recruitment during bacterial skin infection.

    PubMed

    Abtin, Arby; Jain, Rohit; Mitchell, Andrew J; Roediger, Ben; Brzoska, Anthony J; Tikoo, Shweta; Cheng, Qiang; Ng, Lai Guan; Cavanagh, Lois L; von Andrian, Ulrich H; Hickey, Michael J; Firth, Neville; Weninger, Wolfgang

    2014-01-01

    Transendothelial migration of neutrophils in postcapillary venules is a key event in the inflammatory response against pathogens and tissue damage. The precise regulation of this process is incompletely understood. We report that perivascular macrophages are critical for neutrophil migration into skin infected with the pathogen Staphylococcus aureus. Using multiphoton intravital microscopy we showed that neutrophils extravasate from inflamed dermal venules in close proximity to perivascular macrophages, which are a major source of neutrophil chemoattractants. The virulence factor α-hemolysin produced by S. aureus lyses perivascular macrophages, which leads to decreased neutrophil transmigration. Our data illustrate a previously unrecognized role for perivascular macrophages in neutrophil recruitment to inflamed skin and indicate that S. aureus uses hemolysin-dependent killing of these cells as an immune evasion strategy. PMID:24270515

  16. The Perivascular Niche and Self-Renewal of Stem Cells

    PubMed Central

    Oh, Min; Nör, Jacques E.

    2015-01-01

    Postnatal stem cells are typically found in niches that provide signaling cues to maintain their self-renewal and multipotency. While stem cell populations may serve distinct purposes within their tissue of origin, understanding the conserved biology of stem cells and their respective niches provides insights to the behavior of these cells during homeostasis and tissue repair. Here, we discuss perivascular niches of two distinct stem cell populations (i.e., hematopoietic stem cells, mesenchymal stem cells) and explore mechanisms that sustain these stem cells postnatally. We highlight work that demonstrates the impact of cellular crosstalk to stem cell self-renewal and maintenance of functional perivascular niches. We also discuss the importance of the crosstalk within the perivascular niche to the biology of stem cells, and describe the regenerative potential of perivascular cells. We postulate that signaling events that establish and/or stabilize the perivascular niche, particularly through the modulation of self-renewing factors, are key to the long-term success of regenerated tissues. PMID:26696901

  17. Fibrinogen-induced perivascular microglial clustering is required for the development of axonal damage in neuroinflammation

    PubMed Central

    Davalos, Dimitrios; Kyu Ryu, Jae; Merlini, Mario; Baeten, Kim M.; Le Moan, Natacha; Petersen, Mark A.; Deerinck, Thomas J.; Smirnoff, Dimitri S.; Bedard, Catherine; Hakozaki, Hiroyuki; Gonias Murray, Sara; Ling, Jennie B.; Lassmann, Hans; Degen, Jay L.; Ellisman, Mark H.; Akassoglou, Katerina

    2012-01-01

    Blood-brain barrier disruption, microglial activation and neurodegeneration are hallmarks of multiple sclerosis. However, the initial triggers that activate innate immune responses and their role in axonal damage remain unknown. Here we show that the blood protein fibrinogen induces rapid microglial responses toward the vasculature and is required for axonal damage in neuroinflammation. Using in vivo two-photon microscopy, we demonstrate that microglia form perivascular clusters before myelin loss or paralysis onset and that, of the plasma proteins, fibrinogen specifically induces rapid and sustained microglial responses in vivo. Fibrinogen leakage correlates with areas of axonal damage and induces reactive oxygen species release in microglia. Blocking fibrin formation with anticoagulant treatment or genetically eliminating the fibrinogen binding motif recognized by the microglial integrin receptor CD11b/CD18 inhibits perivascular microglial clustering and axonal damage. Thus, early and progressive perivascular microglial clustering triggered by fibrinogen leakage upon blood-brain barrier disruption contributes to axonal damage in neuroinflammatory disease. PMID:23187627

  18. Perivascular deletion of murine Rac reverses the ratio of marrow arterioles and sinusoid vessels and alters hematopoiesis in vivo.

    PubMed

    Ciuculescu, Marioara F; Park, Shin-Young; Canty, Kimberly; Mathieu, Ronald; Silberstein, Leslie E; Williams, David A

    2015-05-14

    Hematopoietic stem cells (HSCs) are localized within specialized microenvironments throughout the BM. Nestin-expressing (Nestin(+)) mesenchymal stromal cells (MSCs) are important in the perivascular space. Rac is critical for MSC cell shape in vitro, whereas its function in MSCs in vivo remains poorly characterized. We hypothesized that deletion of Rac in the Nestin(+) cells would perturb the perivascular space, altering HSC localization and hematopoiesis. Nestin-Cre-directed excision of Rac1 in Rac3(-/-) mice reduces Nestin(+) cells in the marrow. We observed a 2.7-fold decrease in homing of labeled wild-type hematopoietic cells into Rac1(Δ/Δ)Rac3(-/-) mice compared with control mice. Rac1(Δ/Δ)Rac3(-/-) mice demonstrated a marked decrease in arterioles and an increase in the number and volume of venous sinusoids in the marrow that was associated with a reduction in the numbers of immunophenotypically and functionally-defined long-term HSCs in the marrow, a decrease in colony-forming cells and a reduction in circulating progenitors. Rac-deleted animals demonstrated a significant increase in trabecular bone. These data demonstrate that Rac GTPases play an important role in the integrity of perivascular space. Increased trabecular bone and sinusoidal space and decreased arteriolar volume in this model were associated with decreased HSC, underscoring the complexity of regulation of hematopoiesis in the perivascular space.

  19. Perivascular Arrest of CD8+ T Cells Is a Signature of Experimental Cerebral Malaria

    PubMed Central

    Strangward, Patrick; Dandamudi, Durga B.; Coles, Jonathan A.; Villegas-Mendez, Ana; Gallego-Delgado, Julio; van Rooijen, Nico; Zindy, Egor; Rodriguez, Ana; Brewer, James M.; Couper, Kevin N.; Dustin, Michael L.

    2015-01-01

    There is significant evidence that brain-infiltrating CD8+ T cells play a central role in the development of experimental cerebral malaria (ECM) during Plasmodium berghei ANKA infection of C57BL/6 mice. However, the mechanisms through which they mediate their pathogenic activity during malaria infection remain poorly understood. Utilizing intravital two-photon microscopy combined with detailed ex vivo flow cytometric analysis, we show that brain-infiltrating T cells accumulate within the perivascular spaces of brains of mice infected with both ECM-inducing (P. berghei ANKA) and non-inducing (P. berghei NK65) infections. However, perivascular T cells displayed an arrested behavior specifically during P. berghei ANKA infection, despite the brain-accumulating CD8+ T cells exhibiting comparable activation phenotypes during both infections. We observed T cells forming long-term cognate interactions with CX3CR1-bearing antigen presenting cells within the brains during P. berghei ANKA infection, but abrogation of this interaction by targeted depletion of the APC cells failed to prevent ECM development. Pathogenic CD8+ T cells were found to colocalize with rare apoptotic cells expressing CD31, a marker of endothelial cells, within the brain during ECM. However, cellular apoptosis was a rare event and did not result in loss of cerebral vasculature or correspond with the extensive disruption to its integrity observed during ECM. In summary, our data show that the arrest of T cells in the perivascular compartments of the brain is a unique signature of ECM-inducing malaria infection and implies an important role for this event in the development of the ECM-syndrome. PMID:26562533

  20. Perivascular M2 Macrophages Stimulate Tumor Relapse after Chemotherapy

    PubMed Central

    Hughes, Russell; Qian, Bin-Zhi; Rowan, Charlotte; Muthana, Munitta; Keklikoglou, Ioanna; Olson, Oakley C.; Tazzyman, Simon; Danson, Sarah; Addison, Christina; Clemons, Mark; Gonzalez-Angulo, Ana Maria; Joyce, Johanna A.; De Palma, Michele; Pollard, Jeffrey W.; Lewis, Claire E.

    2016-01-01

    Tumor relapse after chemotherapy-induced regression is a major clinical problem, because it often involves inoperable metastatic disease. Tumor-associated macrophages (TAM) are known to limit the cytotoxic effects of chemotherapy in preclinical models of cancer. Here, we report that an alternatively activated (M2) subpopulation of TAMs (MRC1+TIE2HiCXCR4Hi) accumulate around blood vessels in tumors after chemotherapy, where they promote tumor revascularization and relapse, in part, via VEGF-A release. A similar perivascular, M2-related TAM subset was present in human breast carcinomas and bone metastases after chemotherapy. Although a small proportion of M2 TAMs were also present in hypoxic tumor areas, when we genetically ablated their ability to respond to hypoxia via hypoxia-inducible factors 1 and 2, tumor relapse was unaffected. TAMs were the predominant cells expressing immunoreactive CXCR4 in chemotherapy-treated mouse tumors, with the highest levels expressed by MRC1+ TAMs clustering around the tumor vasculature. Furthermore, the primary CXCR4 ligand, CXCL12, was upregulated in these perivascular sites after chemotherapy, where it was selectively chemotactic for MRC1+ TAMs. Interestingly, HMOX-1, a marker of oxidative stress, was also upregulated in perivascular areas after chemotherapy. This enzyme generates carbon monoxide from the breakdown of heme, a gas known to upregulate CXCL12. Finally, pharmacologic blockade of CXCR4 selectively reduced M2-related TAMs after chemotherapy, especially those in direct contact with blood vessels, thereby reducing tumor revascularization and regrowth. Our studies rationalize a strategy to leverage chemotherapeutic efficacy by selectively targeting this perivascular, relapse-promoting M2-related TAM cell population. PMID:26269531

  1. Perivascular mast cells regulate vein graft neointimal formation and remodeling

    PubMed Central

    Grassia, Gianluca; Cambrook, Helen; Ialenti, Armando; MacRitchie, Neil; Carberry, Jaclyn; Lawrence, Catherine

    2015-01-01

    Objective. Emerging evidence suggests an important role for mast cells in vein graft failure. This study addressed the hypothesis that perivascular mast cells regulate in situ vascular inflammatory and proliferative responses and subsequent vein graft neointimal lesion formation, using an optimized local mast cell reconstitution method. Methods and Results. Neointimal hyperplasia was induced by insertion of a vein graft into the right carotid artery in wild type and mast cell deficient KitW−sh/W−sh mice. In some experiments, mast cells were reconstituted systemically (tail vein injection of bone marrow-derived mast cells) or locally (directly into the right neck area) prior to vein grafting. Vein graft neointimal lesion formation was significantly (P < 0.05) reduced in KitW−sh/W−sh mice. Mast cell deficiency reduced the number of proliferating cells, and inhibited L-selectin, CCL2, M-CSF and MIP-3α expression in the vein grafts. Local but not systemic mast cell reconstitution restored a perivascular mast cell population that subsequently promoted neointimal formation in mast cell deficient mice. Conclusion. Our data demonstrate that perivascular mast cells play a key role in promoting neointima formation by inducing local acute inflammatory and proliferative responses. These results suggest that ex vivo intraoperative targeting of mast cells may have therapeutic potential for the prevention of pathological vein graft remodeling. PMID:26312183

  2. Therapeutic potential of perivascular cells from human pluripotent stem cells.

    PubMed

    Dar, Ayelet; Itskovitz-Eldor, Joseph

    2015-09-01

    Vascularization of injured tissues or artificial grafts is a major challenge in tissue engineering, stimulating a continued search for alternative sources for vasculogenic cells and the development of therapeutic strategies. Human pluripotent stem cells (hPSCs), either embryonic or induced, offer a plentiful platform for the derivation of large numbers of vasculogenic cells, as required for clinical transplantations. Various protocols for generation of vasculogenic smooth muscle cells (SMCs) from hPSCs have been described with considerably different SMC derivatives. In addition, we recently identified hPSC-derived pericytes, which are similar to their physiological counterparts, exhibiting unique features of blood vessel-residing perivascular cells, as well as multipotent mesenchymal precursors with therapeutic angiogenic potential. In this review we refer to methodologies for the development of a variety of perivascular cells from hPSCs with respect to developmental induction, differentiation capabilities, potency and their dual function as mesenchymal precursors. The therapeutic effect of hPSC-derived perivascular cells in experimental models of tissue engineering and regenerative medicine are described and compared to those of their native physiological counterparts.

  3. Perivascular Stromal Cells as a Potential Reservoir of Human Cytomegalovirus

    PubMed Central

    Soland, M. A.; Keyes, L. R.; Bayne, R.; Moon, J.; Porada, C. D.; St. Jeor, S.; Almeida-Porada, G.

    2014-01-01

    Human cytomegalovirus (HCMV) infection is an important cause of morbidity and mortality among both solid organ and hematopoietic stem cell transplant recipients. Identification of cells throughout the body that can potentially serve as a viral reservoir is essential to dissect mechanisms of cell tropism and latency and to develop novel therapies. Here, we tested and compared the permissivity of liver-, brain-, lung (LNG)- and bone marrow (BM)-derived perivascular mesenchymal stromal cells (MSC) to HCMV infection and their ability to propagate and produce infectious virus. Perivascular MSC isolated from the different organs have in common the expression of CD146 and Stro-1. While all these cells were permissive to HCMV infection, the highest rate of HCMV infection was seen with LNG-MSC, as determined by viral copy number and production of viral particles by these cells. In addition, we showed that, although the supernatants from each of the HCMV-infected cultures contained infectious virus, the viral copy number and the quantity and timing of virus production varied among the various organ-specific MSC. Furthermore, using quantitative polymerase chain reaction, we were able to detect HCMV DNA in BM-MSC isolated from 7 out of 19 healthy, HCMV-seropositive adults, suggesting that BM-derived perivascular stromal cells may constitute an unrecognized natural HCMV reservoir. PMID:24592822

  4. Ultrastructural spectrum of solitary fibrous tumor: a unique perivascular tumor with alternative lines of differentiation.

    PubMed

    Ide, Fumio; Obara, Kumi; Mishima, Kenji; Saito, Ichiro; Kusama, Kaoru

    2005-06-01

    Eight tumors diagnosed as solitary fibrous tumor (SFT) of the oral cavity were studied. Histologic spectrum was entirely comparable with the extrapleural SFT of other sites. One tumor had glomus tumor-like foci. Immunohistochemical results confirmed most of the previous observations, indicating characteristic expression of vimentin, CD34, bcl-2, and CD99. Factor XIIIa and alpha-smooth muscle actin were less commonly reactive and a very few cells were faintly positive for factor VIII-related antigen and Ulex europaeus agglutinin 1. All were essentially negative for S-100 protein, desmin, CD31, and CD68. In stark contrast to the conclusive immunoprofile, ultrastructural investigation of six tumors demonstrated considerable cellular heterogeneity. Other than fibroblasts, perivascular undifferentiated cells and pericytes predominated, but endothelial cells were regularly present. There was a distinctive proliferation of pericytic cells in four tumors, one of which had glomoid foci of myopericytes. The extreme increase in number of Weibel-Palade bodies occurred in voluminous capillary endothelium. Occasional single and clustered cells with consistent features of endothelium showed intracytoplasmic lumen formation. Such composite cells constituted an integral segment of richly vascularized SFT. Myofibroblastic form smooth muscle differentiation was present in only a minority of cells. From phenotypic analysis by electron microscopy, SFT may originate from a unique, perivascular multipotent mesenchyme sharing with its lineage with pericytes, fibroblasts, and infrequently, endothelium. Consequently, morphological features of SFT may become diversely varied by whether predominantly constituent cells are undifferentiated, pericytic or fibroblastic in nature.

  5. Disproportionate subarachnoid space hydrocephalus—outcome and perivascular space

    PubMed Central

    Akiguchi, Ichiro; Shirakashi, Yoshitomo; Budka, Herbert; Watanabe, Yuko; Watanabe, Toshiyuki; Shiino, Akihiko; Ogita, Mihoko; Kawamoto, Yasuhiro; Jungwirth, Susanne; Krampla, Wolfgang; Fischer, Peter

    2014-01-01

    Objective We sought to identify the prevalence of MRI features of disproportionately enlarged subarachnoid space hydrocephalus in possible idiopathic normal pressure hydrocephalus (DESH-iNPH) and to describe the clinico-radiological features and outcomes of a community-based investigation (The Vienna Trans-Danube Aging study). Methods Of the 697 inhabitants (all 75 years old), 503 completed extensive neurological examinations at baseline and were followed up every 30 months thereafter with MRIs, mini-mental state examination (MMSE), and the Unified Parkinson Disease Rating Scale-Motor Section (UPDRSM). The DESH-iNPH participant data were compared with the data from participants with Evans index ratios >0.3 (ex vacuo hydrocephalus), cerebral small-vessel diseases, and normal MRIs. The widening of perivascular space was also evaluated by MRI in these groups. Results Eight participants with DESH-iNPH (1.6%) and 76 with ex vacuo hydrocephalus (16.1%) at baseline were identified. The mean MMSE in DESH-iNPH, ex vacuo hydrocephalus, and normal MRIs was 26.4, 27.9, and 28.3, respectively, and the mean UPDRSM was 9.75, 2.96, and 1.87, respectively. After a 90-month follow-up, the mortality rates for DESH-iNPH, ex vacuo hydrocephalus, and normal MRIs were 25.0%, 21.3%, and 10.9%, respectively. The perivascular-space widening scores were significantly smaller in the DESH-iNPH cases, particularly at the centrum semiovale, compared to cerebral small-vessel disease and ex vacuo hydrocephalus cases. Interpretation The prevalence of DESH-iNPH was 1.6% for participants aged 75 years and revealed significantly lower MMSE and higher UPDRSM scores compared to the ex vacuo hydrocephalus and controls. Moreover, it is suggested that perivascular-space narrowing is a morphological and pathophysiological marker of DESH-iNPH. PMID:25356428

  6. A systematic review: perivascular epithelioid cell tumor of gastrointestinal tract

    PubMed Central

    Chen, Zehong; Han, Siqi; Wu, Jialin; Xiong, Minmin; Huang, Yanqiao; Chen, Jianhui; Yuan, Yujie; Peng, Jianjun; Song, Wu

    2016-01-01

    Abstract Perivascular epithelioid cell tumor (PEComa) is a rare entity with distinctive morphology and of expressing myomelanocytic markers. Gastrointestinal tract (GI) is one of the most common anatomic sites of origin and counts for 20% to 25% of all reported cases of perivascular epithelioid cell tumors not otherwise specified (PEComas-NOS). However, the biologic behavior of perivascular epithelioid cell tumors of gastrointestinal tract (GI PEComas-NOS) is still unclear. The aim of conducting this systematic review is to sum up what is known so far of the epidemiology, natural history, management and prognosis of GI PEComas-NOS. A systematic research was performed on PubMed and EMBASE using the following terms: (“perivascular epithelioid cell tumor” or “PEComa”) and (“gastrointestinal tract” or “GI” or “oral ” or “mouth” or “esophagus” or “gullet” or “gastric” or “stomach” or “duodenum” or “jejunum” or “ileum” or “cecum” or “colon” or “colorectal” or “sigmoid” or “rectum” or “anus” or “mesentery”) up to December 1, 2015. Retrieved GI PEComas-NOS publications, which included these terms, contains case reports, case series to case characteristic researches. A total of 168 articles were reviewed, 41 GI PEComa-NOS English studies among which were retrieved for analysis. We reviewed epidemiology, natural history, management and prognosis of GI PEComa-NOS. Generally GI PEComa-NOS is believed to have women predomination. The most frequently involved location is colon with non-specific clinical signs. Pathologically, GI PEComas-NOS shows epithelioid predominance (70%), meanwhile coexpresses melanocytic and muscle markers characteristically, while immunohistochemistry is a useful tool for identify, which indicates that HMB-45 is regarded as the most sensitive reagent. Complete resection served as mainstay of treatment, while chemotherapy should be unanimously considered to apply in malignant

  7. A systematic review: perivascular epithelioid cell tumor of gastrointestinal tract.

    PubMed

    Chen, Zehong; Han, Siqi; Wu, Jialin; Xiong, Minmin; Huang, Yanqiao; Chen, Jianhui; Yuan, Yujie; Peng, Jianjun; Song, Wu

    2016-07-01

    Perivascular epithelioid cell tumor (PEComa) is a rare entity with distinctive morphology and of expressing myomelanocytic markers. Gastrointestinal tract (GI) is one of the most common anatomic sites of origin and counts for 20% to 25% of all reported cases of perivascular epithelioid cell tumors not otherwise specified (PEComas-NOS). However, the biologic behavior of perivascular epithelioid cell tumors of gastrointestinal tract (GI PEComas-NOS) is still unclear. The aim of conducting this systematic review is to sum up what is known so far of the epidemiology, natural history, management and prognosis of GI PEComas-NOS.A systematic research was performed on PubMed and EMBASE using the following terms: ("perivascular epithelioid cell tumor" or "PEComa") and ("gastrointestinal tract" or "GI" or "oral " or "mouth" or "esophagus" or "gullet" or "gastric" or "stomach" or "duodenum" or "jejunum" or "ileum" or "cecum" or "colon" or "colorectal" or "sigmoid" or "rectum" or "anus" or "mesentery") up to December 1, 2015. Retrieved GI PEComas-NOS publications, which included these terms, contains case reports, case series to case characteristic researches.A total of 168 articles were reviewed, 41 GI PEComa-NOS English studies among which were retrieved for analysis. We reviewed epidemiology, natural history, management and prognosis of GI PEComa-NOS. Generally GI PEComa-NOS is believed to have women predomination. The most frequently involved location is colon with non-specific clinical signs. Pathologically, GI PEComas-NOS shows epithelioid predominance (70%), meanwhile coexpresses melanocytic and muscle markers characteristically, while immunohistochemistry is a useful tool for identify, which indicates that HMB-45 is regarded as the most sensitive reagent. Complete resection served as mainstay of treatment, while chemotherapy should be unanimously considered to apply in malignant cases. Eventually, it is necessary for closed and long-term follow-up with endoscope and

  8. Therapeutic Angiogenesis Using Local Perivascular and Pericardial Delivery.

    PubMed

    Laham; Post; Sellke; Simons

    2000-08-01

    Therapeutic angiogenesis is a potential new treatment strategy that promises to grow new blood vessels to the ischemic myocardium in patients with ischemic heart disease. Despite its investigation in more than 550 patients with ischemic heart disease, the concept of clinical therapeutic angiogenesis remains a theoretic one with more questions than answers. This is due in part to a poor understanding of the fundamental mechanisms of adult collateralization and growth factor-induced angiogenesis, a poor understanding of the relative importance of large epicardial feeding collaterals versus intramyocardial neovascularization, and limited data concerning the best angiogenic cytokine, the best delivery modality, and the need for sustained exposure to that cytokine. This article discusses the available data on local perivascular delivery and pericardial delivery as they pertain to therapeutic angiogenesis. These delivery strategies have several characteristics that may make them ideal as adjuncts for coronary artery bypass surgery (local perivascular delivery) or in noninstrumented pericardium (pericardial delivery). They also have the theoretic advantage of affecting epicardial vessels and potentially promoting epicardial feeding collaterals.

  9. Intrastriatal convection-enhanced delivery results in widespread perivascular distribution in a pre-clinical model

    PubMed Central

    2012-01-01

    Background Convection-enhanced delivery (CED), a direct method for drug delivery to the brain through intraparenchymal microcatheters, is a promising strategy for intracerebral pharmacological therapy. By establishing a pressure gradient at the tip of the catheter, drugs can be delivered in uniform concentration throughout a large volume of interstitial fluid. However, the variables affecting perivascular distribution of drugs delivered by CED are not fully understood. The aim of this study was to determine whether the perivascular distribution of solutes delivered by CED into the striatum of rats is affected by the molecular weight of the infused agent, by co-infusion of vasodilator, alteration of infusion rates or use of a ramping regime. We also wanted to make a preliminary comparison of the distribution of solutes with that of nanoparticles. Methods We analysed the perivascular distribution of 4, 10, 20, 70, 150 kDa fluorescein-labelled dextran and fluorescent nanoparticles at 10 min and 3 h following CED into rat striatum. We investigated the effect of local vasodilatation, slow infusion rates and ramping on the perivascular distribution of solutes. Co-localisation with perivascular basement membranes and vascular endothelial cells was identified by immunohistochemistry. The uptake of infusates by perivascular macrophages was quantified using stereological methods. Results Widespread perivascular distribution and macrophage uptake of fluorescein-labelled dextran was visible 10 min after cessation of CED irrespective of molecular weight. However, a significantly higher proportion of perivascular macrophages had taken up 4, 10 and 20 kDa fluorescein-labelled dextran than 150 kDa dextran (p < 0.05, ANOVA). Co-infusion with vasodilator, slow infusion rates and use of a ramping regime did not alter the perivascular distribution. CED of fluorescent nanoparticles indicated that particles co-localise with perivascular basement membranes throughout the striatum but

  10. PERIVASCULAR EPITHELIOID TUMOURS (PEComas) OF THE GYNAECOLOGICAL TRACT

    PubMed Central

    Conlon, Niamh; Soslow, Robert A.; Murali, Rajmohan

    2016-01-01

    Perivascular epithelioid tumour (PEComas) of the gynaecological tract are rare tumours which were first recognised and diagnosed within the last twenty years. They represent a unique diagnostic challenge with regard to their accurate and reproducible distinction from more common entities such as smooth muscle tumours of the uterine corpus. In this review article we trace the development of the concept of the PEComa tumour family, highlight what is known about extra-gynaecological tract PEComa at an immunohistochemical, molecular and therapeutic level and then present a summary of all reported cases of gynaecological tract PEComa to date. In the summary, we highlight rare subtypes of gynaecological tract PEComa, and compare the performances of extant prognostic classification systems for malignancy in these tumours. PMID:25750268

  11. Regional differences in perivascular adipose tissue impacting vascular homeostasis.

    PubMed

    Gil-Ortega, Marta; Somoza, Beatriz; Huang, Yu; Gollasch, Maik; Fernández-Alfonso, Maria S

    2015-07-01

    Perivascular adipose tissue (PVAT) releases several important vasoactive factors with physiological and pathophysiological paracrine effects. A large body of evidence suggests regional phenotypic and functional differences among PVAT depots, depending on the specific vascular bed or different regions in the vascular bed where the PVAT is located. These non-uniform and separate PVATs exert various paracrine effects on vascular structure and function that largely impact disease states, such as endothelial dysfunction, atherosclerosis, or insulin resistance. This emerging view of PVAT function requires considering heterogeneous PVAT as a specialized organ that can differentially regulate vascular function depending on its anatomical location. In this context, the adipose-vascular axis may represent a novel target for pharmacological intervention in vasculopathy in cardiometabolic disorders.

  12. Tissue Engineered Perivascular Endothelial Cell Implants Regulate Vascular Injury

    NASA Astrophysics Data System (ADS)

    Nathan, Aruna; Nugent, Matthew A.; Edelman, Elazer R.

    1995-08-01

    Molecular biomaterial engineering permits in vivo transplantation of cells and tissues, offering the promise of restoration of physiologic control rather than pharmacologic dosing with isolated compounds. We engrafted endothelial cells on Gelfoam biopolymeric matrices with retention of viability, normal growth kinetics, immunoreactivity, and biochemical activity. The production of heparan sulfate proteoglycan and inhibition of basic fibroblast growth factor binding and activity by engrafted cells were indistinguishable from endothelial cells grown in culture. Perivascular implantation of Gelfoam-endothelial cell scaffolds around balloon-denuded rat carotid arteries reduced intimal hyperplasia 88.1%, far better than the isolated administration of heparin, the most effective endothelial mimic compound. In concert with a reduction in intimal area, cell proliferation was reduced by >90%. To our knowledge, there have been no previous reports of extravascular cell implants controlling vasculoproliferative disease. Tissue engineered cells offer the potential for potent methods of vascular growth regulation and insight into the complex autocrine-paracrine control mechanisms within the blood vessel wall.

  13. Perivascular fat, AMP-activated protein kinase and vascular diseases

    PubMed Central

    Almabrouk, T A M; Ewart, M A; Salt, I P; Kennedy, S

    2014-01-01

    Perivascular adipose tissue (PVAT) is an active endocrine and paracrine organ that modulates vascular function, with implications for the pathophysiology of cardiovascular disease (CVD). Adipocytes and stromal cells contained within PVAT produce mediators (adipokines, cytokines, reactive oxygen species and gaseous compounds) with a range of paracrine effects modulating vascular smooth muscle cell contraction, proliferation and migration. However, the modulatory effect of PVAT on the vascular system in diseases, such as obesity, hypertension and atherosclerosis, remains poorly characterized. AMP-activated protein kinase (AMPK) regulates adipocyte metabolism, adipose biology and vascular function, and hence may be a potential therapeutic target for metabolic disorders such as type 2 diabetes mellitus (T2DM) and the vascular complications associated with obesity and T2DM. The role of AMPK in PVAT or the actions of PVAT have yet to be established, however. Activation of AMPK by pharmacological agents, such as metformin and thiazolidinediones, may modulate the activity of PVAT surrounding blood vessels and thereby contribute to their beneficial effect in cardiometabolic diseases. This review will provide a current perspective on how PVAT may influence vascular function via AMPK. We will also attempt to demonstrate how modulating AMPK activity using pharmacological agents could be exploited therapeutically to treat cardiometabolic diseases. PMID:24490856

  14. Perivascular carotid inflammation: an unusual case of carotidynia.

    PubMed

    Azar, Lama; Fischer, Harry D

    2012-02-01

    A 59-year-old woman was admitted to the hospital with a fever and rigors for 2 days. She was on chemotherapy (docetaxel, carboplatin, and trastuzumab) for her stage II invasive ductal carcinoma of the breast. Her physical exam was unremarkable except for the fever. The white blood cells were 21,200/mm(3) with 92% of neutrophils. ESR was 106 mm/h. An extensive infectious workup was negative. On day 6, while still febrile, the patient complained of a left-sided neck pain. She exhibited tenderness over the left carotid artery. A CT scan of the neck without intravenous contrast showed perivascular inflammation of the left common carotid artery, without evidence of a collection, arterial thrombosis, aneurysm, or dissection. The etiology of this finding was possibly chemotherapy related. It dramatically responded to oral prednisone. A repeat CT scan of the neck with IV contrast 2 weeks later showed a remarkable improvement. Drug reactions can simulate systemic inflammatory diseases and should always be considered in the diagnosing process.

  15. Microscopic endometrial perivascular epithelioid cell nodules: a case report with the earliest presentation of a uterine perivascular epithelioid cell tumor.

    PubMed

    Fang, Chia-Lang; Lin, Yun-Ho; Chen, Wei-Yu

    2012-09-03

    Perivascular epithelioid cell (PEC) tumors (PEComas) are a family of related mesenchymal tumors composed of PECs which co-express melanocytic and smooth muscle markers. Although their distinctive histologic, immunohistochemical, ultrastructural, and genetic features have been clearly demonstrated, their histogenesis and normal counterpart remain largely unknown. Precursor lesions of PEComas have rarely been reported. We herein describe a tuberous sclerosis patient with microscopic PEC nodules in the endometrium of adenomyosis, pelvic endometriosis, an ovarian endometriotic cyst, and the endometrium of the uterine cavity. The nodules showed a mixture of spindle-shaped and epithelioid cells concentrically arranged around small arteries. The cells exhibited uniform nuclei, light eosinophilic cytoplasm, and immunoreactivity with HMB-45 and CD10. Some nodules revealed continuity with a PEComa in the myometrium. These findings support microscopic endometrial PEC nodules possibly being precursor lesions of uterine PEComas. The wide distribution of the nodules in the pelvis may be related to the multicentricity of PEComas in tuberous sclerosis patients. Owing to the immunoreactivity with CD10, microscopic endometrial PEC nodules may be misinterpreted as endothelial stromal cells unless melanocytic markers are stained. To the best of our knowledge, this is a case with the earliest manifestation of PEC lesions occurring in the endometrium. Virtual slides: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/9658280017862643.

  16. The pericyte antigen RGS5 in perivascular soft tissue tumors☆,☆☆

    PubMed Central

    Shen, Jia; Shrestha, Swati; Yen, Yu-Hsin; Scott, Michelle A.; Soo, Chia; Ting, Kang; Peault, Bruno; Dry, Sarah M.; James, Aaron W.

    2016-01-01

    Summary Perivascular soft tissue tumors are relatively uncommon neoplasms of unclear lineage of differentiation, although most are presumed to originate from or differentiate to pericytes or a modified perivascular cell. Among these, glomus tumor, myopericytoma, and angioleiomyoma share a spectrum of histologic findings and a perivascular growth pattern. In contrast, solitary fibrous tumor was once hypothesized to have pericytic differentiation—although little bona fide evidence of pericytic differentiation exists. Likewise the perivascular epithelioid cell tumor (PEComa) family shares a perivascular growth pattern, but with distinctive dual myoid-melanocytic differentiation. RGS5, regulator of G-protein signaling 5, is a novel pericyte antigen with increasing use in animal models. Here, we describe the immunohistochemical expression patterns of RGS5 across perivascular soft tissue tumors, including glomus tumor (n = 6), malignant glomus tumor (n = 4), myopericytoma (n = 3), angioleiomyoma (n = 9), myofibroma (n = 4), solitary fibrous tumor (n = 10), and PEComa (n = 19). Immunohistochemical staining and semi-quantification was performed, and compared to αSMA (smooth muscle actin) expression. Results showed that glomus tumor (including malignant glomus tumor), myopericytoma, and angioleiomyoma shared a similar diffuse immunoreactivity for RGS5 and αSMA across all tumors examined. In contrast, myofibroma, solitary fibrous tumor and PEComa showed predominantly focal to absent RGS5 immunoreactivity. These findings further support a common pericytic lineage of differentiation in glomus tumors, myopericytoma and angioleiomyoma. The pericyte marker RGS5 may be of future clinical utility for the evaluation of pericytic differentiation in soft tissue tumors. PMID:26558691

  17. Arterial pulsation-driven cerebrospinal fluid flow in the perivascular space: a computational model.

    PubMed

    Bilston, Lynne E; Fletcher, David F; Brodbelt, Andrew R; Stoodley, Marcus A

    2003-08-01

    This study was conducted to determine whether local arterial pulsations are sufficient to cause cerebrospinal fluid (CSF) flow along perivascular spaces (PVS) within the spinal cord. A theoretical model of the perivascular space surrounding a "typical" small artery was analysed using computational fluid dynamics. Systolic pulsations were modelled as travelling waves on the arterial wall. The effects of wave geometry and variable pressure conditions on fluid flow were investigated. Arterial pulsations induce fluid movement in the PVS in the direction of arterial wave travel. Perivascular flow continues even in the presence of adverse pressure gradients of a few kilopascals. Flow rates are greater with increasing pulse wave velocities and arterial deformation, as both an absolute amplitude and as a proportion of the PVS. The model suggests that arterial pulsations are sufficient to cause fluid flow in the perivascular space even against modest adverse pressure gradients. Local increases in flow in this perivascular pumping mechanism or reduction in outflow may be important in the etiology of syringomyelia.

  18. Decidualization induces a secretome switch in perivascular niche cells of the human endometrium.

    PubMed

    Murakami, Keisuke; Lee, Yie Hou; Lucas, Emma S; Chan, Yi-Wah; Durairaj, Ruban Peter; Takeda, Satoru; Moore, Jonathan D; Tan, Bee K; Quenby, Siobhan; Chan, Jerry K Y; Gargett, Caroline E; Brosens, Jan J

    2014-11-01

    The endometrial perivascular microenvironment is rich in mesenchymal stem-like cells that express type 1 integral membrane protein Sushi domain containing 2 (SUSD2) but the role of these cells in the decidual transformation of this tissue in pregnancy is unknown. We used an antibody directed against SUSD2 (W5C5) to isolate perivascular (W5C5(+)) and nonperivascular (W5C5(-)) fibroblasts from mid-luteal biopsies. We show that SUSD2 expression, and hence the ratio of W5C5(+):W5C5(-) cells, changes in culture depending on cell-cell contact and activation of the Notch signaling pathway. RNA sequencing revealed that cultures derived from W5C5(+) progenitor cells remain phenotypically distinct by the enrichment of novel and established endometrial perivascular signature genes. In an undifferentiated state, W5C5(+)-derived cells produced lower levels of various chemokines and inflammatory modulators when compared with their W5C5(-) counterparts. This divergence in secretomes was switched and became more pronounced upon decidualization, which transformed perivascular W5C5(+) cells into the dominant source of a range of chemokines and cytokines, including leukemia inhibitory factor and chemokine (C-C motif) ligand 7. Our findings suggest that the decidual response is spatially organized at the embryo-maternal interface with differentiating perivascular cells establishing distinct cytokine and chemokine profiles that could potentially direct trophoblast toward maternal vessels and govern local immune responses in pregnancy. PMID:25116707

  19. Perivascular Stem Cells: A Prospectively Purified Mesenchymal Stem Cell Population for Bone Tissue Engineering

    PubMed Central

    James, Aaron W.; Zara, Janette N.; Zhang, Xinli; Askarinam, Asal; Goyal, Raghav; Chiang, Michael; Yuan, Wei; Chang, Le; Corselli, Mirko; Shen, Jia; Pang, Shen; Stoker, David; Wu, Ben

    2012-01-01

    Adipose tissue is an ideal source of mesenchymal stem cells for bone tissue engineering: it is largely dispensable and readily accessible with minimal morbidity. However, the stromal vascular fraction (SVF) of adipose tissue is a heterogeneous cell population, which leads to unreliable bone formation. In the present study, we prospectively purified human perivascular stem cells (PSCs) from adipose tissue and compared their bone-forming capacity with that of traditionally derived SVF. PSCs are a population (sorted by fluorescence-activated cell sorting) of pericytes (CD146+CD34−CD45−) and adventitial cells (CD146−CD34+CD45−), each of which we have previously reported to have properties of mesenchymal stem cells. Here, we found that PSCs underwent osteogenic differentiation in vitro and formed bone after intramuscular implantation without the need for predifferentiation. We next sought to optimize PSCs for in vivo bone formation, adopting a demineralized bone matrix for osteoinduction and tricalcium phosphate particle formulation for protein release. Patient-matched, purified PSCs formed significantly more bone in comparison with traditionally derived SVF by all parameters. Recombinant bone morphogenetic protein 2 increased in vivo bone formation but with a massive adipogenic response. In contrast, recombinant Nel-like molecule 1 (NELL-1; a novel osteoinductive growth factor) selectively enhanced bone formation. These studies suggest that adipose-derived human PSCs are a new cell source for future efforts in skeletal regenerative medicine. Moreover, PSCs are a stem cell-based therapeutic that is readily approvable by the U.S. Food and Drug Administration, with potentially increased safety, purity, identity, potency, and efficacy. Finally, NELL-1 is a candidate growth factor able to induce human PSC osteogenesis. PMID:23197855

  20. Imaging the Perivascular Space as a Potential Biomarker of Neurovascular and Neurodegenerative Diseases.

    PubMed

    Ramirez, Joel; Berezuk, Courtney; McNeely, Alicia A; Gao, Fuqiang; McLaurin, JoAnne; Black, Sandra E

    2016-03-01

    Although the brain lacks conventional lymphatic vessels found in peripheral tissue, evidence suggests that the space surrounding the vasculature serves a similar role in the clearance of fluid and metabolic waste from the brain. With aging, neurodegeneration, and cerebrovascular disease, these microscopic perivascular spaces can become enlarged, allowing for visualization and quantification on structural MRI. The purpose of this review is to: (i) describe some of the recent pre-clinical findings from basic science that shed light on the potential neurophysiological mechanisms driving glymphatic and perivascular waste clearance, (ii) review some of the pathobiological etiologies that may lead to MRI-visible enlarged perivascular spaces (ePVS), (iii) describe the possible clinical implications of ePVS, (iv) evaluate existing qualitative and quantitative techniques used for measuring ePVS burden, and (v) propose future avenues of research that may improve our understanding of this potential clinical neuroimaging biomarker for fluid and metabolic waste clearance dysfunction in neurodegenerative and neurovascular diseases.

  1. Human Perivascular Stem Cell-Based Bone Graft Substitute Induces Rat Spinal Fusion

    PubMed Central

    Chung, Choon G.; James, Aaron W.; Asatrian, Greg; Chang, Le; Nguyen, Alan; Le, Khoi; Bayani, Georgina; Lee, Robert; Stoker, David; Zhang, Xinli

    2014-01-01

    Adipose tissue is an attractive source of mesenchymal stem cells (MSCs) because of its abundance and accessibility. We have previously defined a population of native MSCs termed perivascular stem cells (PSCs), purified from diverse human tissues, including adipose tissue. Human PSCs (hPSCs) are a bipartite cell population composed of pericytes (CD146+CD34−CD45−) and adventitial cells (CD146−CD34+CD45−), isolated by fluorescence-activated cell sorting and with properties identical to those of culture identified MSCs. Our previous studies showed that hPSCs exhibit improved bone formation compared with a sample-matched unpurified population (termed stromal vascular fraction); however, it is not known whether hPSCs would be efficacious in a spinal fusion model. To investigate, we evaluated the osteogenic potential of freshly sorted hPSCs without culture expansion and differentiation in a rat model of posterolateral lumbar spinal fusion. We compared increasing dosages of implanted hPSCs to assess for dose-dependent efficacy. All hPSC treatment groups induced successful spinal fusion, assessed by manual palpation and microcomputed tomography. Computerized biomechanical simulation (finite element analysis) further demonstrated bone fusion with hPSC treatment. Histological analyses showed robust endochondral ossification in hPSC-treated samples. Finally, we confirmed that implanted hPSCs indeed differentiated into osteoblasts and osteocytes; however, the majority of the new bone formation was of host origin. These results suggest that implanted hPSCs positively regulate bone formation via direct and paracrine mechanisms. In summary, hPSCs are a readily available MSC population that effectively forms bone without requirements for culture or predifferentiation. Thus, hPSC-based products show promise for future efforts in clinical bone regeneration and repair. PMID:25154782

  2. An abundant perivascular source of stem cells for bone tissue engineering.

    PubMed

    James, Aaron W; Zara, Janette N; Corselli, Mirko; Askarinam, Asal; Zhou, Ann M; Hourfar, Alireza; Nguyen, Alan; Megerdichian, Silva; Asatrian, Greg; Pang, Shen; Stoker, David; Zhang, Xinli; Wu, Benjamin; Ting, Kang; Péault, Bruno; Soo, Chia

    2012-09-01

    Adipose tissue is an ideal mesenchymal stem cell (MSC) source, as it is dispensable and accessible with minimal morbidity. However, the stromal vascular fraction (SVF) of adipose tissue is a heterogeneous cell population, which has disadvantages for tissue regeneration. In the present study, we prospectively purified human perivascular stem cells (PSCs) from n = 60 samples of human lipoaspirate and documented their frequency, viability, and variation with patient demographics. PSCs are a fluorescence-activated cell sorting-sorted population composed of pericytes (CD45-, CD146+, CD34-) and adventitial cells (CD45-, CD146-, CD34+), each of which we have previously reported to have properties of MSCs. Here, we found that PSCs make up, on average, 43.2% of SVF from human lipoaspirate (19.5% pericytes and 23.8% adventitial cells). These numbers were minimally changed by age, gender, or body mass index of the patient or by length of refrigerated storage time between liposuction and processing. In a previous publication, we observed that human PSCs (hPSCs) formed significantly more bone in vivo in comparison with unsorted human SVF (hSVF) in an intramuscular implantation model. We now extend this finding to a bone injury model, observing that purified hPSCs led to significantly greater healing of mouse critical-size calvarial defects than hSVF (60.9% healing as opposed to 15.4% healing at 2 weeks postoperative by microcomputed tomography analysis). These studies suggest that adipose-derived hPSCs are a new cell source for future efforts in skeletal regenerative medicine. Moreover, hPSCs are a stem cell-based therapeutic that is readily approvable by the U.S. Food and Drug Administration, with potentially increased safety, purity, identity, potency, and efficacy.

  3. Perivascular Spaces--MRI Marker of Inflammatory Activity in the Brain?

    ERIC Educational Resources Information Center

    Wuerfel, Jens; Haertle, Mareile; Waiczies, Helmar; Tysiak, Eva; Bechmann, Ingo; Wernecke, Klaus D.; Zipp, Frauke; Paul, Friedemann

    2008-01-01

    The Virchow-Robin spaces (VRS), perivascular compartments surrounding small blood vessels as they penetrate the brain parenchyma, are increasingly recognized for their role in leucocyte trafficking as well as for their potential to modulate immune responses. In the present study, we investigated VRS numbers and volumes in different brain regions…

  4. Malignant Perivascular Epithelioid Cell Neoplasm (PEComa) of the Pelvis: A Case Report.

    PubMed

    D'Andrea, David; Hanspeter, Esther; D'Elia, Carolina; Martini, Thomas; Pycha, Armin

    2016-05-01

    Perivascular epithelioid cell neoplasms (PEComa) are rare mesenchymal tumors that can occur in any part of the body and have unpredictable pathological behavior. They are usually benign, but may be malignant. We present a case of malignant PEComa of the pelvic retroperitoneum treated with radical surgery.

  5. Differentiation and migration properties of human foetal umbilical cord perivascular cells: potential for lung repair

    PubMed Central

    Montemurro, Tiziana; Andriolo, Gabriella; Montelatici, Elisa; Weissmann, Gaia; Crisan, Mihaela; Colnaghi, Maria Rosa; Rebulla, Paolo; Mosca, Fabio; Péault, Bruno; Lazzari, Lorenza

    2011-01-01

    Abstract Mesenchymal stem cells (MSC) have been derived from different cultured human tissues, including bone marrow, adipose tissue, amniotic fluid and umbilical cord blood. Only recently it was suggested that MSC descended from perivascular cells, the latter being defined as CD146+ neuro-glial proteoglycan (NG)2+ platelet-derived growth factor-Rβ+ ALP+ CD34– CD45– von Willebrand factor (vWF)– CD144–. Herein we studied the properties of perivascular cells from a novel source, the foetal human umbilical cord (HUC) collected from pre-term newborns. By immunohistochemistry and flow cytometry we show that pre-term/foetal HUCs contain more perivascular cells than their full-term counterparts (2.5%versus 0.15%). Moreover, foetal HUC perivascular cells (HUCPC) express the embryonic cell markers specific embryonic antigen-4, Runx1 and Oct-4 and can be cultured over the long term. To further confirm the MSC identity of these cultured perivascular cells, we also showed their expression at different passages of antigens that typify MSC. The multilineage differentiative capacity of HUCPC into osteogenic, adipogenic and myogenic cell lineages was demonstrated in culture. In the perspective of a therapeutic application in chronic lung disease of pre-term newborns, we demonstrated the in vitro ability of HUCPC to migrate towards an alveolar type II cell line damaged with bleomycin, an anti-cancer agent with known pulmonary toxicity. The secretory profile exhibited by foetal HUCPC in the migration assay suggested a paracrine effect that could be exploited in various clinical conditions including lung disorders. PMID:20219017

  6. A Rapamycin-Releasing Perivascular Polymeric Sheath Produces Highly Effective Inhibition of Intimal Hyperplasia

    PubMed Central

    Yu, Xaohua; Takayama, Toshio; Goel, Shakti A.; Shi, Xudong; Zhou, Yifan; Kent, K. Craig; Murphy, William L.; Guo, Lian-Wang

    2014-01-01

    Intimal hyperplasia produces restenosis (re-narrowing) of the vessel lumen following vascular intervention. Drugs that inhibit intimal hyperplasia have been developed, however there is currently no clinical method of perivascular drug-delivery to prevent restenosis following open surgical procedures. Here we report a poly(ε-caprolactone) (PCL) sheath that is highly effective in preventing intimal hyperplasia through perivascular delivery of rapamycin. We first screened a series of bioresorbable polymers, i.e., poly(lactide-co-glycolide) (PLGA), poly(lactic acid) (PLLA), PCL, and their blends, to identify desired release kinetics and sheath physical properties. Both PLGA and PLLA sheaths produced minimal (<30%) rapamycin release within 50 days in PBS buffer. In contrast, PCL sheaths exhibited more rapid and near-linear release kinetics, as well as durable integrity (>90 days) as evidenced in both scanning electron microscopy and subcutaneous embedding experiments. Moreover, a PCL sheath deployed around balloon-injured rat carotid arteries was associated with a minimum rate of thrombosis compared to PLGA and PLLA. Morphometric analysis and immunohistochemistry revealed that rapamycin-loaded perivascular PCL sheaths produced pronounced (85%) inhibition of intimal hyperplasia (0.15±0.05 vs 1.01±0.16), without impairment of the luminal endothelium, the vessel’s anti-thrombotic layer. Our data collectively show that a rapamycin-loaded PCL delivery system produces substantial mitigation of neointima, likely due to its favorable physical properties leading to a stable yet flexible perivascular sheath and steady and prolonged release kinetics. Thus, a PCL sheath may provide useful scaffolding for devising effective perivascular drug delivery particularly suited for preventing restenosis following open vascular surgery. PMID:24852098

  7. Sclerosing variant of perivascular epithelioid cell tumor in the female genital organs.

    PubMed

    Yamada, Yuichi; Yamamoto, Hidetaka; Ohishi, Yoshihiro; Nishiyama, Kenichi; Fukuhara, Masao; Saitou, Toshiaki; Tsuneyoshi, Masazumi; Oda, Yoshinao

    2011-12-01

    Perivascular epithelioid cell tumor (PEComas), other than angiomyolipoma, clear cell 'sugar' tumor of the lung, and lymphangioleiomyomatosis, is an uncommon mesenchymal neoplasm that arises in the soft tissue and visceral organs. We report herein two cases of sclerosing PEComa; a distinctive variant of PEComa, which is characterized by extensive stromal hyalinization, occurring in the uterus and broad ligament. The patients were 34- and 51-year-old females with no family history of tuberous sclerosis complex. Macroscopically, the tumors had white to gray cut surfaces and were microscopically composed of predominantly spindle- to polygon-shaped cells with clear to slightly eosinophilic cytoplasm and pleomorphic nuclei focally arranged in a perivascular pattern, accompanied by marked stromal hyalinization. These tumor cells were immunohistochemically positive for HMB45 and α-smooth muscle actin. Although this variant of PEComa is very rare, this entity should be considered as a potential primary neoplasm of the female genital organs.

  8. Cutaneous perivascular epithelioid cell tumors: A review on an infrequent neoplasm

    PubMed Central

    Llamas-Velasco, Mar; Requena, Luis; Mentzel, Thomas

    2016-01-01

    Perivascular epithelioid cutaneous” cell tumors (PEComa) are a family of mesenchymal tumors with shared microscopic and immunohistochemical properties: They exhibit both smooth muscle cell and melanocytic differentiation. Non-neoplastic counterpart of PEComa’s cells are unknown, as well as the relationship between extracutaneous PEComa and primary cutaneous ones. We will review the clinical setting, histopathologic features, chromosomal abnormalities, differential diagnosis and treatment options for cutaneous PEComa. PMID:27019799

  9. Potential interactions between pericytes and oligodendrocyte precursor cells in perivascular regions of cerebral white matter

    PubMed Central

    Maki, Takakuni; Maeda, Mitsuyo; Uemura, Maiko; Lo, Evan K.; Terasaki, Yasukazu; Liang, Anna C.; Shindo, Akihiro; Choi, Yoon Kyung; Taguchi, Akihiko; Matsuyama, Tomohiro; Takahashi, Ryosuke; Ihara, Masafumi; Arai, Ken

    2015-01-01

    Pericytes are embedded within basal lamina and play multiple roles in the perivascular niche in brain. Recently, oligodendrocyte precursor cells (OPCs) have also been reported to associate with cerebral endothelium. Is it possible that within this gliovascular locus, there may also exist potential spatial and functional interactions between pericytes and OPCs? Here, we demonstrated that in the perivascular region of cerebral white matter, pericytes and OPCs may attach and support each other. Immunostaining showed that pericytes and OPCs are localized in close contact with each other in mouse white matter at postnatal days 0, 60 and 240. Electron microscopic analysis confirmed that pericytes attached to OPCs via basal lamina in the perivascular region. The close proximity between these two cell types was also observed in postmortem human brains. Functional interaction between pericytes and OPCs was assessed by in vitro media transfer experiments. When OPC cultures were treated with pericyte-conditioned media, OPC number increased. Similarly, pericyte number increased when pericytes were maintained in OPC-conditioned media. Taken together, our data suggest a potential anatomical and functional interaction between pericytes and OPCs in cerebral white matter. PMID:25936593

  10. Pulsed ultrasound expands the extracellular and perivascular spaces of the brain.

    PubMed

    Hersh, David S; Nguyen, Ben A; Dancy, Jimena G; Adapa, Arjun R; Winkles, Jeffrey A; Woodworth, Graeme F; Kim, Anthony J; Frenkel, Victor

    2016-09-01

    Diffusion within the extracellular and perivascular spaces of the brain plays an important role in biological processes, therapeutic delivery, and clearance mechanisms within the central nervous system. Recently, ultrasound has been used to enhance the dispersion of locally administered molecules and particles within the brain, but ultrasound-mediated effects on the brain parenchyma remain poorly understood. We combined an electron microscopy-based ultrastructural analysis with high-resolution tracking of non-adhesive nanoparticles in order to probe changes in the extracellular and perivascular spaces of the brain following a non-destructive pulsed ultrasound regimen known to alter diffusivity in other tissues. Freshly obtained rat brain neocortical slices underwent sham treatment or pulsed, low intensity ultrasound for 5min at 1MHz. Transmission electron microscopy revealed intact cells and blood vessels and evidence of enlarged spaces, particularly adjacent to blood vessels, in ultrasound-treated brain slices. Additionally, ultrasound significantly increased the diffusion rate of 100nm, 200nm, and 500nm nanoparticles that were injected into the brain slices, while 2000nm particles were unaffected. In ultrasound-treated slices, 91.6% of the 100nm particles, 20.7% of the 200nm particles, 13.8% of the 500nm particles, and 0% of the 2000nm particles exhibited diffusive motion. Thus, pulsed ultrasound can have meaningful structural effects on the brain extracellular and perivascular spaces without evidence of tissue disruption. PMID:27369449

  11. Imaging the Perivascular Space as a Potential Biomarker of Neurovascular and Neurodegenerative Diseases.

    PubMed

    Ramirez, Joel; Berezuk, Courtney; McNeely, Alicia A; Gao, Fuqiang; McLaurin, JoAnne; Black, Sandra E

    2016-03-01

    Although the brain lacks conventional lymphatic vessels found in peripheral tissue, evidence suggests that the space surrounding the vasculature serves a similar role in the clearance of fluid and metabolic waste from the brain. With aging, neurodegeneration, and cerebrovascular disease, these microscopic perivascular spaces can become enlarged, allowing for visualization and quantification on structural MRI. The purpose of this review is to: (i) describe some of the recent pre-clinical findings from basic science that shed light on the potential neurophysiological mechanisms driving glymphatic and perivascular waste clearance, (ii) review some of the pathobiological etiologies that may lead to MRI-visible enlarged perivascular spaces (ePVS), (iii) describe the possible clinical implications of ePVS, (iv) evaluate existing qualitative and quantitative techniques used for measuring ePVS burden, and (v) propose future avenues of research that may improve our understanding of this potential clinical neuroimaging biomarker for fluid and metabolic waste clearance dysfunction in neurodegenerative and neurovascular diseases. PMID:26993511

  12. Pharmacological evidence for CGRP uptake into perivascular capsaicin sensitive nerve terminals

    PubMed Central

    Sams-Nielsen, Anette; Orskov, Cathrine; Jansen-Olesen, Inger

    2001-01-01

    Specific mechanisms, providing reuptake of cathecholamine and amino acid neurotransmitters (e.g. serotonin and glutamate) into cells of the central nervous system are well known, whereas neuronal uptake of neuropeptide transmitters have not previously been reported. In the present study we present evidence for uptake of the 37 amino acid neuropeptide, calcitonin gene-related peptide (CGRP) into perivascular terminals of capsaicin sensitive nerve fibres, innervating the guinea-pig basilar artery. Release of CGRP from perivascular nerve terminals was obtained by capsaicin-induced vanilloid receptor-stimulation and detected as CGRP receptor-mediated dilation of isolated segments of the guinea-pig basilar artery. Following three repeated capsaicin challenges, CGRP-depleted segments were incubated with CGRP. This caused significant reappearance of capsaicin-induced vasodilatory responses. These responses were dependent on duration and concentration of the preceding CGRP incubation and were inhibited by the CGRP receptor antagonist, CGRP8–37. The CGRP-re-depletion was significantly reduced when CGRP8–37 was present during the preceding CGRP incubation. Thus, presynaptic CGRP receptors are likely to be involved in neuronal CGRP uptake. Incubating the artery segments with 125I-CGRP allowed subsequent detection of capsaicin-induced 125I-release. Immunohistochemical experiments showed that only terminal CGRP is subject to capsaicin-induced depletion in vitro, whereas CGRP-immunoreactivity endures in the nerve fibres. PMID:11226146

  13. Selective capture of endothelial and perivascular cells from brain microvessels using laser capture microdissection.

    PubMed

    Kinnecom, Katie; Pachter, Joel S

    2005-12-01

    Laser capture microdissection (LCM) of the major cell types comprising brain microvessels offers a powerful technology to explore the molecular basis of the blood-brain barrier in health and disease. However, the ability to selectively retrieve endothelial or perivascular cells, without cross-contamination from the other, has proven difficult. Additionally, histochemical methods previously described for use with LCM have not allowed for identification of all the different size branches of the microvascular tree. Here, we describe a double immunostaining method, combining bright-field and fluorescence microscopy, and using an extensive dehydration with xylene, to clearly identify and spatially resolve endothelial from perivascular cells within all size microvascular branches in frozen brain sections. LCM of these sections, coupled with RNA analysis by reverse-transcription polymerase chain reaction, revealed that captured endothelial cells show endothelial markers but no detectable markers for astrocytes or smooth muscle cells/pericytes. Conversely, captured astrocytes or smooth muscle cells/pericytes demonstrate their respective markers, but not those of endothelial cells. This approach has applicability to microarray analysis, thereby enabling global gene profiling of the different cell types along the entirety of the brain microvascular tree.

  14. Human coronary artery perivascular adipocytes overexpress genes responsible for regulating vascular morphology, inflammation, and hemostasis

    PubMed Central

    Aronow, Bruce J.; Tong, Wilson S.; Manka, David; Tang, Yaoliang; Bogdanov, Vladimir Y.; Unruh, Dusten; Blomkalns, Andra L.; Piegore, Mark G.; Weintraub, Daniel S.; Rudich, Steven M.; Kuhel, David G.; Hui, David Y.; Weintraub, Neal L.

    2013-01-01

    Inflammatory cross talk between perivascular adipose tissue and the blood vessel wall has been proposed to contribute to the pathogenesis of atherosclerosis. We previously reported that human perivascular (PV) adipocytes exhibit a proinflammatory phenotype and less adipogenic differentiation than do subcutaneous (SQ) adipocytes. To gain a global view of the genomic basis of biologic differences between PV and SQ adipocytes, we performed genome-wide expression analyses to identify differentially expressed genes between adipocytes derived from human SQ vs. PV adipose tissues. Although >90% of well-expressed genes were similarly regulated, we identified a signature of 307 differentially expressed genes that were highly enriched for functions associated with the regulation of angiogenesis, vascular morphology, inflammation, and blood clotting. Of the 156 PV upregulated genes, 59 associate with angiogenesis, vascular biology, or inflammation, noteworthy of which include TNFRSF11B (osteoprotegerin), PLAT, TGFB1, THBS2, HIF1A, GATA6, and SERPINE1. Of 166 PV downregulated genes, 21 associated with vascular biology and inflammation, including ANGPT1, ANGPTL1, and VEGFC. Consistent with the emergent hypothesis that PV adipocytes differentially regulate angiogenesis and inflammation, cell culture-derived adipocyte-conditioned media from PV adipocytes strongly enhanced endothelial cell tubulogenesis and monocyte migration compared with media from SQ adipocytes. These findings demonstrate that PV adipocytes have the potential to significantly modulate vascular inflammatory crosstalk in the setting of atherosclerosis by their ability to signal to both endothelial and inflammatory cells. PMID:23737535

  15. Improving recognition of hepatic perivascular epithelioid cell tumor: Case report and literature review

    PubMed Central

    Maebayashi, Toshiya; Abe, Katsumi; Aizawa, Takuya; Sakaguchi, Masakuni; Ishibashi, Naoya; Abe, Osamu; Takayama, Tadatoshi; Nakayama, Hisashi; Matsuoka, Shunichi; Nirei, Kazushige; Nakamura, Hitomi; Ogawa, Masahiro; Sugitani, Masahiko

    2015-01-01

    A 58-year-old man presented with the chief complaint of abdominal bloating and was incidentally found to have a liver tumor. As diagnostic imaging studies could not rule out malignancy, the patient underwent partial resection of segment 3 of the liver. The lesion pathologically showed eosinophilic proliferation, in addition to immunohistochemical positivity for human melanoma black 45 and Melan-A, thereby leading to the diagnosis of a hepatic perivascular epithelioid cell tumor (PEComa). A PEComa arising from the liver is relatively rare. Moreover, the name ‘PEComa’ has not yet been widely recognized, and the same disease entity has been called epithelioid angiomyolipoma (EAML), further diminishing the recognition of PEComa. In addition, PEComa imaging findings mimic those of malignant liver tumors, and clinically, this tumor tends to enlarge. Therefore, a PEComa is difficult to diagnose. We conducted a systematic review of PEComa and EAML cases and discuss the results, including findings useful for differentiating perivascular epithelioid cell tumors from malignant liver tumors. PMID:25954119

  16. Histamine H(3) receptor-mediated modulation of perivascular nerve transmission in rat mesenteric arteries.

    PubMed

    Sun, Pengyuan; Takatori, Shingo; Jin, Xin; Koyama, Toshihiro; Tangsucharit, Panot; Li, Simin; Zamami, Yoshito; Kitamura, Yoshihisa; Kawasaki, Hiromu

    2011-03-25

    The rat mesenteric artery has been shown to be innervated by adrenergic vasoconstrictor nerves and calcitonin gene-related peptide (CGRP)-containing (CGRPergic) vasodilator nerves. The present study was designed to investigate the involvement of histamine H(3) receptors in the neurotransmission of perivascular adrenergic and CGRPergic nerves. The mesenteric vascular beds without an endothelium isolated from male Wistar rats were perfused with Krebs solution and perfusion pressure was measured. In preparations with resting tension, the selective H(3) receptor agonist (R)-α-methylhistamine (α-methylhistamine; 10-100nM) significantly reduced periarterial nerve stimulation (2-8Hz)-induced vasoconstriction and noradrenaline release in the perfusate without an effect on the vasoconstriction induced by exogenously injected noradrenaline (0.5, 1.0nmol). In preparations with active tone produced by methoxamine (2μM) and in the presence of guanethidine (5μM), the periarterial nerve stimulation (1, 2Hz)-induced vasodilator response was inhibited by α-methylhistamine (0.1-1μM) perfusion without affecting vasodilation induced by exogenously injected CGRP (5pmol). Clobenpropit (histamine H(3) receptor antagonist, 1μM) canceled the α-methylhistamine-induced decrease in the periarterial nerve stimulation-induced vasoconstriction and noradrenaline release and periarterial nerve stimulation-induced vasodilation. These results suggest that the stimulation of H(3) receptors located in rat perivascular nerves inhibits presynaptically the neurotransmission of not only adrenergic nerves, but also CGRP nerves, by decreasing neurotransmitters.

  17. Local Control of Perivascular Malignant Liver Lesions Using Percutaneous Irreversible Electroporation: Initial Experiences

    SciTech Connect

    Eller, Achim Schmid, Axel; Schmidt, Joachim; May, Matthias Brand, Michael Saake, Marc Uder, Michael Lell, Michael

    2015-02-15

    PurposeThis study was designed to assess efficacy and safety in the treatment of perivascular malignant liver lesions using percutaneous, computed tomography (CT)-guided irreversible electroporation (IRE).MethodsFourteen patients (mean age 58 ± 11 years) with 18 malignant liver lesions were consecutively enrolled in this study. IRE was performed in patients not eligible for surgery and lesions abutting large vessels or bile ducts. Follow-up exams were performed using multislice-CT (MS-CT) or MRI.ResultsMedium lesion diameter was 20 ± 5 mm. Ten of 14 (71 %) were successfully treated with no local recurrence to date (mean follow-up 388 ± 160 days). One case left initial tumor control unclear and additional RFA was performed 4 weeks after IRE. Complications occurred in 4 of 14 (29 %) cases. In one case, intervention was terminated and abdominal bleeding required laparotomy. In two cases, a postinterventional hematothorax required intervention. In another case, abdominal bleeding could be managed conservatively. No complications related to the bile ducts occurred.ConclusionsPercutaneous IRE seems to be effective in perivascular lesions but is associated with a higher complication rate compared with thermoablative techniques.

  18. Perivascular Mast Cells Govern Shear Stress-Induced Arteriogenesis by Orchestrating Leukocyte Function.

    PubMed

    Chillo, Omary; Kleinert, Eike Christian; Lautz, Thomas; Lasch, Manuel; Pagel, Judith-Irina; Heun, Yvonn; Troidl, Kerstin; Fischer, Silvia; Caballero-Martinez, Amelia; Mauer, Annika; Kurz, Angela R M; Assmann, Gerald; Rehberg, Markus; Kanse, Sandip M; Nieswandt, Bernhard; Walzog, Barbara; Reichel, Christoph A; Mannell, Hanna; Preissner, Klaus T; Deindl, Elisabeth

    2016-08-23

    The body has the capacity to compensate for an occluded artery by creating a natural bypass upon increased fluid shear stress. How this mechanical force is translated into collateral artery growth (arteriogenesis) is unresolved. We show that extravasation of neutrophils mediated by the platelet receptor GPIbα and uPA results in Nox2-derived reactive oxygen radicals, which activate perivascular mast cells. These c-kit(+)/CXCR-4(+) cells stimulate arteriogenesis by recruiting additional neutrophils as well as growth-promoting monocytes and T cells. Additionally, mast cells may directly contribute to vascular remodeling and vascular cell proliferation through increased MMP activity and by supplying growth-promoting factors. Boosting mast cell recruitment and activation effectively promotes arteriogenesis, thereby protecting tissue from severe ischemic damage. We thus find that perivascular mast cells are central regulators of shear stress-induced arteriogenesis by orchestrating leukocyte function and growth factor/cytokine release, thus providing a therapeutic target for treatment of vascular occlusive diseases.

  19. EphrinB2 drives perivascular invasion and proliferation of glioblastoma stem-like cells

    PubMed Central

    Krusche, Benjamin; Ottone, Cristina; Clements, Melanie P; Johnstone, Ewan R; Goetsch, Katrin; Lieven, Huang; Mota, Silvia G; Singh, Poonam; Khadayate, Sanjay; Ashraf, Azhaar; Davies, Timothy; Pollard, Steven M; De Paola, Vincenzo; Roncaroli, Federico; Martinez-Torrecuadrada, Jorge; Bertone, Paul; Parrinello, Simona

    2016-01-01

    Glioblastomas (GBM) are aggressive and therapy-resistant brain tumours, which contain a subpopulation of tumour-propagating glioblastoma stem-like cells (GSC) thought to drive progression and recurrence. Diffuse invasion of the brain parenchyma, including along preexisting blood vessels, is a leading cause of therapeutic resistance, but the mechanisms remain unclear. Here, we show that ephrin-B2 mediates GSC perivascular invasion. Intravital imaging, coupled with mechanistic studies in murine GBM models and patient-derived GSC, revealed that endothelial ephrin-B2 compartmentalises non-tumourigenic cells. In contrast, upregulation of the same ephrin-B2 ligand in GSC enabled perivascular migration through homotypic forward signalling. Surprisingly, ephrin-B2 reverse signalling also promoted tumourigenesis cell-autonomously, by mediating anchorage-independent cytokinesis via RhoA. In human GSC-derived orthotopic xenografts, EFNB2 knock-down blocked tumour initiation and treatment of established tumours with ephrin-B2-blocking antibodies suppressed progression. Thus, our results indicate that targeting ephrin-B2 may be an effective strategy for the simultaneous inhibition of invasion and proliferation in GBM. DOI: http://dx.doi.org/10.7554/eLife.14845.001 PMID:27350048

  20. Perivascular innervation: A multiplicity of roles in vasomotor control and myoendothelial signaling

    PubMed Central

    Westcott, Erika B.; Segal, Steven S.

    2013-01-01

    The control of vascular resistance and tissue perfusion reflect coordinated changes in the diameter of feed arteries and the arteriolar networks they supply. Against a background of myogenic tone and metabolic demand, vasoactive signals originating from perivascular sympathetic and sensory nerves are integrated with endothelium-derived signals to produce vasodilation or vasoconstriction. PVNs release adrenergic, cholinergic, peptidergic, purinergic, and nitrergic neurotransmitters that lead to SMC contraction or relaxation via their actions on SMCs, ECs, or other PVNs. ECs release autacoids that can have opposing actions on SMCs. Respective cell layers are connected directly to each other through GJs at discrete sites via MEJs projecting through holes in the IEL. Whereas studies of intercellular communication in the vascular wall have centered on endothelium-derived signals that govern SMC relaxation, attention has increasingly focused on signaling from SMCs to ECs. Thus, via MEJs, neurotransmission from PVNs can evoke distinct responses from ECs subsequent to acting on SMCs. To integrate this emerging area of investigation in light of vasomotor control, the present review synthesizes current understanding of signaling events that originate within SMCs in response to perivascular neurotransmission in light of EC feedback. Though often ignored in studies of the resistance vasculature, PVNs are integral to blood flow control and can provide a physiological stimulus for myoendothelial communication. Greater understanding of these underlying signaling events and how they may be affected by aging and disease will provide new approaches for selective therapeutic interventions. PMID:23289720

  1. Perivascular Mast Cells Govern Shear Stress-Induced Arteriogenesis by Orchestrating Leukocyte Function.

    PubMed

    Chillo, Omary; Kleinert, Eike Christian; Lautz, Thomas; Lasch, Manuel; Pagel, Judith-Irina; Heun, Yvonn; Troidl, Kerstin; Fischer, Silvia; Caballero-Martinez, Amelia; Mauer, Annika; Kurz, Angela R M; Assmann, Gerald; Rehberg, Markus; Kanse, Sandip M; Nieswandt, Bernhard; Walzog, Barbara; Reichel, Christoph A; Mannell, Hanna; Preissner, Klaus T; Deindl, Elisabeth

    2016-08-23

    The body has the capacity to compensate for an occluded artery by creating a natural bypass upon increased fluid shear stress. How this mechanical force is translated into collateral artery growth (arteriogenesis) is unresolved. We show that extravasation of neutrophils mediated by the platelet receptor GPIbα and uPA results in Nox2-derived reactive oxygen radicals, which activate perivascular mast cells. These c-kit(+)/CXCR-4(+) cells stimulate arteriogenesis by recruiting additional neutrophils as well as growth-promoting monocytes and T cells. Additionally, mast cells may directly contribute to vascular remodeling and vascular cell proliferation through increased MMP activity and by supplying growth-promoting factors. Boosting mast cell recruitment and activation effectively promotes arteriogenesis, thereby protecting tissue from severe ischemic damage. We thus find that perivascular mast cells are central regulators of shear stress-induced arteriogenesis by orchestrating leukocyte function and growth factor/cytokine release, thus providing a therapeutic target for treatment of vascular occlusive diseases. PMID:27524614

  2. Isolated Anxa5{sup +}/Sca-1{sup +} perivascular cells from mouse meningeal vasculature retain their perivascular phenotype in vitro and in vivo

    SciTech Connect

    Brachvogel, Bent . E-mail: bent.brachvogel@uni-koeln.de; Pausch, Friederike; Farlie, Peter; Gaipl, Udo; Etich, Julia; Zhou, Zhigang; Cameron, Trevor; Mark, Klaus von der; Bateman, John F.; Poeschl, Ernst . E-mail: e.poschl@uea.ac.uk

    2007-07-15

    Pericytes are closely associated with endothelial cells, contribute to vascular stability and represent a potential source of mesenchymal progenitor cells. Using the specifically expressed annexin A5-LacZ fusion gene (Anxa5-LacZ), it became possible to isolate perivascular cells (PVC) from mouse tissues. These cells proliferate and can be cultured without undergoing senescence for multiple passages. PVC display phenotypic characteristics of pericytes, as they express pericyte-specific markers (NG2-proteoglycan, desmin, {alpha}SMA, PDGFR-{beta}). They also express stem cell marker Sca-1, whereas endothelial (PECAM), hematopoietic (CD45) or myeloid (F4/80, CD11b) lineage markers are not detectable. These characteristics are in common with the pericyte-like cell line 10T1/2. PVC also display a phagocytoic activity higher than 10T1/2 cells. During coculture with endothelial cells both cell types stimulate angiogenic processes indicated by an increased expression of PECAM in endothelial cells and specific deposition of basement membrane proteins. PVC show a significantly increased induction of endothelial specific PECAM expression compared to 10T1/2 cells. Accordingly, in vivo grafts of PVC aggregates onto chorioallantoic membranes of quail embryos recruit endothelial cells, get highly vascularized and deposit basement membrane components. These data demonstrate that isolated Anxa5-LacZ{sup +} PVC from mouse meninges retain their capacity for differentiation to pericyte-like cells and contribute to angiogenic processes.

  3. Mist1 Expressing Gastric Stem Cells Maintain the Normal and Neoplastic Gastric Epithelium and Are Supported by a Perivascular Stem Cell Niche.

    PubMed

    Hayakawa, Yoku; Ariyama, Hiroshi; Stancikova, Jitka; Sakitani, Kosuke; Asfaha, Samuel; Renz, Bernhard W; Dubeykovskaya, Zinaida A; Shibata, Wataru; Wang, Hongshan; Westphalen, Christoph B; Chen, Xiaowei; Takemoto, Yoshihiro; Kim, Woosook; Khurana, Shradha S; Tailor, Yagnesh; Nagar, Karan; Tomita, Hiroyuki; Hara, Akira; Sepulveda, Antonia R; Setlik, Wanda; Gershon, Michael D; Saha, Subhrajit; Ding, Lei; Shen, Zeli; Fox, James G; Friedman, Richard A; Konieczny, Stephen F; Worthley, Daniel L; Korinek, Vladimir; Wang, Timothy C

    2015-12-14

    The regulation and stem cell origin of normal and neoplastic gastric glands are uncertain. Here, we show that Mist1 expression marks quiescent stem cells in the gastric corpus isthmus. Mist1(+) stem cells serve as a cell-of-origin for intestinal-type cancer with the combination of Kras and Apc mutation and for diffuse-type cancer with the loss of E-cadherin. Diffuse-type cancer development is dependent on inflammation mediated by Cxcl12(+) endothelial cells and Cxcr4(+) gastric innate lymphoid cells (ILCs). These cells form the perivascular gastric stem cell niche, and Wnt5a produced from ILCs activates RhoA to inhibit anoikis in the E-cadherin-depleted cells. Targeting Cxcr4, ILCs, or Wnt5a inhibits diffuse-type gastric carcinogenesis, providing targets within the neoplastic gastric stem cell niche.

  4. A biodegradable perivascular wrap for controlled, local and directed drug delivery

    PubMed Central

    Sanders, William G.; Hogrebe, Paul C.; Grainger, David W.; Cheung, Alfred K.; Terry, Christi M.

    2012-01-01

    Perivascular delivery of anti-proliferative agents is an attractive approach to inhibit hyperplasia that causes stenosis of synthetic hemodialysis grafts and other vascular grafts. Perivascular drug delivery systems typically release drugs to both the vascular wall and non-target extravascular tissue. The objective of this study was to develop a biodegradable, perivascular delivery system for localized, sustained and unidirectional drug release in the context of synthetic arteriovenous (AV) grafts used for chronic hemodialysis. To this end, a dense non-porous polymer barrier layer was laminated to either i) a drug-loaded non-porous polymer layer, or ii) a porous polymer layer. To provide tuneability, the porous layer could be loaded with drug during casting or later infused with a drug-loaded hydrogel. The polymer bilayer wraps were prepared by a solvent casting, thermal-phase inversion technique using either polylactide-co-glycolide (PLGA) or polycaprolactone (PCL). Sunitinib, a multi-target receptor tyrosine kinase inhibitor, was used as a model drug. In a modified transwell chamber system, the barrier function of the non-porous PLGA backing was superior to the non-porous PCL backing although both markedly inhibited drug diffusion. As assessed by in vitro release assays, drug release duration from the drug-loaded non-porous PCL construct was almost 4-fold greater than release from the porous PCL construct infused with drug-laden hydrogel (22 days vs. 5 days); release duration from the drug-loaded non-porous PLGA construct was prolonged approximately 3-fold over release from the porous PLGA construct infused with drug-laden hydrogel (9 days vs. 3 days). Complete in vitro degradation of the PLGA porous and non-porous constructs occurred by approximately 35 days whereas the PCL constructs remained intact even after most drug was released (49 days). The PLGA non-porous bilayer wrap containing 143±5.5 mg sunitinib in the inner layer was chosen for further

  5. Perivascular epithelioid cell tumor of the liver coexisting with a gastrointestinal stromal tumor.

    PubMed

    Paiva, Carlos Eduardo; Moraes Neto, Francisco Alves; Agaimy, Abbas; Custodio Domingues, Maria Aparecida; Rogatto, Silvia Regina

    2008-02-01

    Approximately 10% of patients with gastrointestinal stromal tumors (GIST) develop other neoplasms, either synchronously or metachronously. In this report we describe coexistence of a gastrointestinal stromal tumor and a hepatic perivascular epithelioid cell tumor (PEComa) in a 51-year-old woman with no evidence of tuberous sclerosis. A subcapsular hepatic nodule (0.8 cm in diameter) was found during surgery for symptomatic gastric neoplasm (15 cm in diameter) arising from the lesser curvature. Both tumors revealed histomorphological and immunohistochemical features confirming a diagnosis of a small incidental hepatic PEComa and a high risky extramural gastric GIST, respectively. The patient remained disease-free 25 mo after surgery with no evidence of tumor recurrence or new neoplasms. To our knowledge, this is the first report of PEComa in a patient with GIST. Hepatic lesions detected synchronously or metachronously in patients with GISTs may represent histogenetically distinct lesions and should be sampled to confirm or exclude metastatic GISTs.

  6. TFE3 Translocation Associated Perivascular Epithelioid Cell Neoplasm (PEComa) of the Gynecologic Tract: Morphology, Immunophenotype, Differential Diagnosis

    PubMed Central

    Schoolmeester, J. Kenneth; Dao, Linda N.; Sukov, William R.; Park, Kay J.; Murali, Rajmohan; Hameed, Meera R.; Soslow, Robert A.

    2016-01-01

    TFE3 translocation associated PEComa is a distinct form of perivascular epithelioid cell neoplasm, the features of which are poorly defined owing to their general infrequency and limited prior reports with confirmed rearrangement or fusion totaling nine cases. Recent investigation has found a lack of TSC gene mutation in these tumors compared to their nonrearranged counterparts which underscores the importance of recognizing the translocated variant due to hypothetical ineffectiveness of targeted mTOR inhibitor therapy. Six cases were identified and TFE3 rearrangement was confirmed by FISH. Patient age ranged 46 to 66 years (median 50) and none had a history of tuberous sclerosis complex. Three cases arose in the uterine corpus, one in the vagina, and one pelvic tumor and one pulmonary tumor were likely a recurrence/metastasis from a probable uterine primary. Five cases had purely clear cell epithelioid morphology that showed a spectrum of atypia while one case had a mixture of clear cell epithelioid and spindle cells. A mostly consistent immunophenotype was observed in the purely clear cell epithelioid cases: each demonstrated diffuse TFE3, HMB45, CathepsinK labeling, either focal or no melanA staining and variably weak reactivity to smooth muscle markers. The mixed clear cell epithelioid and spindle cell case had a similar pattern in its epithelioid component, but strong muscle marker positivity in its spindle cell component. Follow up ranged 1 to 57 months. Three cases demonstrated aggressive behavior and three cases had no evidence of recurrence. Both GYN-specific and traditional sets of criteria for malignancy were evaluated. The GYN model showed improved inclusion and specificity in comparison to the traditional model. PMID:25517951

  7. The diagnostic value of perivascular infiltrates in muscle biopsy specimens for the assessment of rheumatoid vasculitis

    PubMed Central

    Voskuyl, A.; van Duinen, S. G; Zwinderman, A.; Breedveld, F.; Hazes, J.

    1998-01-01

    OBJECTIVE—To determine the diagnostic value of perivascular infiltrates (PVI) in randomly obtained muscle biopsy specimens for the assessment of rheumatoid vasculitis (RV).
METHODS—The number and size of PVIs, defined as the presence of mononuclear or polymorphonuclear cells around ⩾ 50% of the circumference of a vessel wall, as well as the presence of fibrinoid necrosis were determined in frozen sections of muscle samples of RV patients with histologically confirmed vasculitis in fixed muscle tissue (n=12). The findings were compared with those observed in frozen sections of muscle biopsy specimens of rheumatoid arthritis (RA) patients not suspected of vasculitis (n=14) and patients with osteoarthritis (OA) (n=11). The presence of PVIs and of fibrinoid necrosis were sought in four frozen sections of the muscle biopsy specimen.
RESULTS—PVIs were observed in 75% of the RV patients, which was significantly (p < 0.05) higher than the frequency found in RA (14%) or OA (18%) patients. PVIs with ⩾ three cell layers were found in 67% of the RV patients and in none of the RA and OA patients (p < 0.05). Fibrinoid necrosis was found in least one of four frozen section in 33% of the RV patients. There was a good intra-observer and inter-observer concordance on the presence of fibrinoid necrosis and of PVIs with ⩾ three cell layers.
CONCLUSIONS—The assessment of PVIs with ⩾ three cell layers in a muscle biopsy specimen is a specific and reliable test in discriminating RV from RA without vasculitis. The demonstration in muscle of PVIs with ⩾ three cell layers is more sensitive than that of fibrinoid necrosis in the diagnosis of RV.

 Keywords: rheumatoid arthritis; vasculitis; diagnosis; histology; perivascular infiltrates PMID:9613342

  8. Perivascular tissue mediated relaxation - a novel player in human vascular tone regulation.

    PubMed

    Deja, M A; Malinowski, M; Golba, K S; Piekarska, M; Wos, S

    2015-12-01

    Perivascular tissue (PVT) modulates vascular tone, releasing adventitia/adipocyte derived relaxing factor (ADRF). Its physiological role remains unclear. We studied isolated internal thoracic artery (ITA) segments obtained from 132 patients subjected to coronary artery bypass grafting. The vessels were skeletonized in vitro and the ITA rings and PVT were incubated in separate isolated organ baths. Skeletonized ITA segments were first precontracted with 10(-5.5)mol/L 5-hydroxytryptamine hydrochloride. The PVT was next transferred to the ITA tissue bath. This resulted in relaxation of ITA, presumably related to ADRF release from PVT which was floating freely in the tissue bath. The in-vitro relaxation responses were then correlated to patients' characteristics - including demographics, clinical and laboratory data, as well as therapy. Perivascular tissue transfer resulted in 49.7 ± 26.2% relaxation of precontracted ITA segments. In multiple linear regression modelling, the relaxation of ITAto PVT was negatively related to patient age (β = -0.67; 95% CI -1.17 - -0.17; P = 0.009), symptoms of CCS class 4 angina (β = -20.11; 95%CI -32.25 - -7.97; P = 0.001), and positively to body mass (β = 0.37; 95%CI 0.08 - 0.67; P = 0.01) and lack of heart failure symptoms (NYHA class 1) (β = 9.06; 95%CI 0.33 - 17.79; P = 0.04). The relaxation response to PVT was not related to patients' sex, diabetes, hypertension, lipid profile or therapy in both univariate and multivariate analysis. PVT might play an important role in regulating vascular tone in humans as exemplified by its changing physiological function with age and in atherosclerosis. PMID:26769833

  9. Characterization of perivascular poly(lactic-co-glycolic acid) films containing paclitaxel.

    PubMed

    Jackson, John K; Smith, Janet; Letchford, Kevin; Babiuk, Kelly Anne; Machan, Lindsay; Signore, Pierre; Hunter, William L; Wang, Kaiyue; Burt, Helen M

    2004-09-28

    The objectives of this study were to investigate the use of poly(lactic-co-glycolic acid) (PLGA) for the formulation of paclitaxel loaded films and to characterize these films for potential application as perivascular "wraps" to prevent restenosis. Films were manufactured from PLGA blended with either methoxypolyethylene glycol (MePEG) or a diblock copolymer composed of poly(D,L-lactic acid)-block-methoxypolyethylene glycol, PDLLA-MePEG (diblock) by solvent evaporation on teflon discs. Elasticity was determined by gravimetric stress/strain analysis. Thermal analysis was determined using differential scanning calorimetry (DSC). Changes in film composition and degradation in aqueous media were determined using gel permeation chromatography (GPC). Paclitaxel release from films was measured by incubation of the films in phosphate buffered saline (PBS) with drug analysis by HPLC methods. The addition of MePEG or diblock to PLGA caused a concentration dependent increase in the elasticity of films, due to plasticizing effects. DSC analysis showed that MePEG and diblock caused a concentration dependent decrease in the glass transition temperature (Tg) of PLGA indicating miscibility of the polymers. When placed in aqueous media, more than 75% of MePEG dissolved out of the PLGA films within 2 days, whereas diblock partitioned slowly and in a controlled manner out of the films. Paclitaxel release from PLGA/MePEG films was very slow with less than 5% of the encapsulated drug being released over 2 weeks. The addition of 30% diblock to paclitaxel loaded PLGA films caused a substantial increase (five- to eight-fold) in the release rate of paclitaxel. PLGA films containing 30% diblock and either 1% or 5% paclitaxel were partially or completely degraded following perivascular implantation in rats. PMID:15363506

  10. Post-radiation fibrosarcoma of the cerebrum associated with a prominent, lace-like, perivascular, desmoplastic change.

    PubMed

    Shintaku, Masayuki; Adachi, Yasushi; Takeuchi, Yasuhide; Yamamoto, Daisuke; Koyama, Junji

    2016-04-01

    An intra-axial tumor measuring about 4 cm was excised from the right temporal lobe of a 35-year-old woman, who had a past history of resection of craniopharyngioma and postoperative radiation 21 years earlier. The tumor involved both the cortex and white matter, but was not attached to the dura mater. It consisted of a dense, interlacing, fascicular proliferation of atypical fibroblastic cells and was associated with an extensive, lace-like, desmoplastic change mainly involving the perivascular region around the tumor and overlying the subarachnoid space. The histopathological features of the desmoplastic change resembled meningioangiomatosis, but no proliferation of meningothelial cells was noted. The patient has been free from recurrence for 12 months since the operation. The association of primary cerebral fibrosarcoma with an extensive, lace-like, perivascular, desmoplastic change has not been documented in the literature. The radiation administered 21 years previously may have played some pathogenetic role in the perivascular desmoplastic change, and a malignant transformation of fibroblasts within the perivascular collagenous tissue is considered the most likely origin of the fibrosarcoma.

  11. Role of chemokine RANTES in the regulation of perivascular inflammation, T-cell accumulation, and vascular dysfunction in hypertension.

    PubMed

    Mikolajczyk, Tomasz P; Nosalski, Ryszard; Szczepaniak, Piotr; Budzyn, Klaudia; Osmenda, Grzegorz; Skiba, Dominik; Sagan, Agnieszka; Wu, Jing; Vinh, Antony; Marvar, Paul J; Guzik, Bartlomiej; Podolec, Jakub; Drummond, Grant; Lob, Heinrich E; Harrison, David G; Guzik, Tomasz J

    2016-05-01

    Recent studies have emphasized the role of perivascular inflammation in cardiovascular disease. We studied mechanisms of perivascular leukocyte infiltration in angiotensin II (Ang II)-induced hypertension and their links to vascular dysfunction. Chronic Ang II infusion in mice increased immune cell content of T cells (255 ± 130 to 1664 ± 349 cells/mg; P < 0.01), M1 and M2 macrophages, and dendritic cells in perivascular adipose tissue. In particular, the content of T lymphocytes bearing CC chemokine receptor (CCR) 1, CCR3, and CCR5 receptors for RANTES chemokine was increased by Ang II (CCR1, 15.6 ± 1.5% vs. 31 ± 5%; P < 0.01). Hypertension was associated with an increase in perivascular adipose tissue expression of the chemokine RANTES (relative quantification, 1.2 ± 0.2 vs. 3.5 ± 1.1; P < 0.05), which induced T-cell chemotaxis and vascular accumulation of T cells expressing the chemokine receptors CCR1, CCR3, and CCR5. Mechanistically, RANTES(-/-) knockout protected against vascular leukocyte, and in particular T lymphocyte infiltration (26 ± 5% in wild type Ang II vs. 15 ± 4% in RANTES(-/-)), which was associated with protection from endothelial dysfunction induced by Ang II. This effect was linked with diminished infiltration of IFN-γ-producing CD8(+) and double-negative CD3(+)CD4(-)CD8(-) T cells in perivascular space and reduced vascular oxidative stress while FoxP3(+) T-regulatory cells were unaltered. IFN-γ ex vivo caused significant endothelial dysfunction, which was reduced by superoxide anion scavenging. In a human cohort, a significant inverse correlation was observed between circulating RANTES levels as a biomarker and vascular function measured as flow-mediated dilatation (R = -0.3, P < 0.01) or endothelial injury marker von Willebrand factor (R = +0.3; P < 0.01). Thus, chemokine RANTES is important in the regulation of vascular dysfunction through modulation of perivascular inflammation.-Mikolajczyk, T. P., Nosalski, R., Szczepaniak, P

  12. Role of chemokine RANTES in the regulation of perivascular inflammation, T-cell accumulation, and vascular dysfunction in hypertension

    PubMed Central

    Mikolajczyk, Tomasz P.; Nosalski, Ryszard; Szczepaniak, Piotr; Budzyn, Klaudia; Osmenda, Grzegorz; Skiba, Dominik; Sagan, Agnieszka; Wu, Jing; Vinh, Antony; Marvar, Paul J.; Guzik, Bartlomiej; Podolec, Jakub; Drummond, Grant; Lob, Heinrich E.; Harrison, David G.; Guzik, Tomasz J.

    2016-01-01

    Recent studies have emphasized the role of perivascular inflammation in cardiovascular disease. We studied mechanisms of perivascular leukocyte infiltration in angiotensin II (Ang II)-induced hypertension and their links to vascular dysfunction. Chronic Ang II infusion in mice increased immune cell content of T cells (255 ± 130 to 1664 ± 349 cells/mg; P < 0.01), M1 and M2 macrophages, and dendritic cells in perivascular adipose tissue. In particular, the content of T lymphocytes bearing CC chemokine receptor (CCR) 1, CCR3, and CCR5 receptors for RANTES chemokine was increased by Ang II (CCR1, 15.6 ± 1.5% vs. 31 ± 5%; P < 0.01). Hypertension was associated with an increase in perivascular adipose tissue expression of the chemokine RANTES (relative quantification, 1.2 ± 0.2 vs. 3.5 ± 1.1; P < 0.05), which induced T-cell chemotaxis and vascular accumulation of T cells expressing the chemokine receptors CCR1, CCR3, and CCR5. Mechanistically, RANTES−/− knockout protected against vascular leukocyte, and in particular T lymphocyte infiltration (26 ± 5% in wild type Ang II vs. 15 ± 4% in RANTES−/−), which was associated with protection from endothelial dysfunction induced by Ang II. This effect was linked with diminished infiltration of IFN-γ-producing CD8+ and double-negative CD3+CD4−CD8− T cells in perivascular space and reduced vascular oxidative stress while FoxP3+ T-regulatory cells were unaltered. IFN-γ ex vivo caused significant endothelial dysfunction, which was reduced by superoxide anion scavenging. In a human cohort, a significant inverse correlation was observed between circulating RANTES levels as a biomarker and vascular function measured as flow-mediated dilatation (R = −0.3, P < 0.01) or endothelial injury marker von Willebrand factor (R = +0.3; P < 0.01). Thus, chemokine RANTES is important in the regulation of vascular dysfunction through modulation of perivascular inflammation.—Mikolajczyk, T. P., Nosalski, R., Szczepaniak, P

  13. Perivascular adipose tissue-secreted angiopoietin-like protein 2 (Angptl2) accelerates neointimal hyperplasia after endovascular injury.

    PubMed

    Tian, Zhe; Miyata, Keishi; Tazume, Hirokazu; Sakaguchi, Hisashi; Kadomatsu, Tsuyoshi; Horio, Eiji; Takahashi, Otowa; Komohara, Yoshihiro; Araki, Kimi; Hirata, Yoichiro; Tabata, Minoru; Takanashi, Shuichiro; Takeya, Motohiro; Hao, Hiroyuki; Shimabukuro, Michio; Sata, Masataka; Kawasuji, Michio; Oike, Yuichi

    2013-04-01

    Much attention is currently focused on the role of perivascular adipose tissue in development of cardiovascular disease (CVD). Some researchers view it as promoting CVD through secretion of cytokines and growth factors called adipokines, while recent reports reveal that perivascular adipose tissue can exert a protective effect on CVD development. Furthermore, adiponectin, an anti-inflammatory adipokine, reportedly suppresses neointimal hyperplasia after endovascular injury, whereas such vascular remodeling is enhanced by pro-inflammatory adipokines secreted by perivascular adipose, such as tumor necrosis factor-α (TNF-α). These findings suggest that extent of vascular remodeling, a pathological process associated with CVD development, depends on the balance between pro- and anti-inflammatory adipokines secreted from perivascular adipose tissue. We previously demonstrated that angiopoietin-like protein 2 (Angptl2), a pro-inflammatory factor secreted by adipose tissue, promotes adipose tissue inflammation and subsequent systemic insulin resistance in obesity. Here, we examined whether Angptl2 secreted by perivascular adipose tissue contributes to vascular remodeling after endovascular injury in studies of transgenic mice expressing Angptl2 in adipose tissue (aP2-Angptl2 transgenic mice) and Angptl2 knockout mice (Angptl2(-/-) mice). To assess the role of Angptl2 secreted by perivascular adipose tissue on vascular remodeling after endovascular injury, we performed adipose tissue transplantation experiments using these mice. Wild-type mice with perivascular adipose tissue derived from aP2-Angptl2 mice exhibited accelerated neointimal hyperplasia after endovascular injury compared to wild-type mice transplanted with wild-type tissue. Conversely, vascular inflammation and neointimal hyperplasia after endovascular injury were significantly attenuated in wild-type mice transplanted with Angptl2(-/-) mouse-derived perivascular adipose tissue compared to wild-type mice

  14. Scar-like lesion on dorsal nose (cellular neurothekeoma)

    PubMed Central

    López-Cepeda, Larissa Dorina; Navarrete-Franco, Gisela; Novales-Santacoloma, Josefa; Enriquez-Merino, Julio

    2007-01-01

    Neurothekeomas are tumors of neural differentiation and of unknown origin that occur in females at the 2nd and 3rd decades of life. They usually affect the face with an unspecific clinical aspect. The histological features include cellular or mixoid differentiation and immunohistochemistry can be positive for protein s-100, vimentin and epithelilal membrane antigen (EMA). This case report presents a 13-year-old female patient with nasal neurothekeoma of cellular variety and strongly positive for vimentin and s-100; and negative for EMA. PMID:18053137

  15. Retrospective Value of Skin Biopsy in Histologically Confirmed Cases of the Perivascular Dermatitis Subgroup of the Inflammatory Dermatoses.

    PubMed

    Tod, Bianca; Jordaan, Henry F; Schneider, Johann W

    2016-01-01

    Skin biopsy is a commonly used and valuable tool in the diagnosis of diseases of the skin. The inflammatory dermatoses are a subgroup that presents diagnostic difficulties from both a clinical and a histopathological perspective. This study examines a particularly challenging subgroup of the inflammatory dermatoses, that is, perivascular dermatitis. The final conclusions of the histological report of 163 biopsies considered to fall into the perivascular dermatitis group were examined, and the value skin biopsy added in the final diagnosis of each case was evaluated. The 2 most valuable potential outcomes of the histopathological report: consistent with clinical diagnosis with strong evidence of a specific diagnosis and new, unexpected, helpful, specific diagnosis, occurred in 40 reports (24.54%).

  16. sdf1 Expression Reveals a Source of Perivascular-Derived Mesenchymal Stem Cells in Zebrafish

    PubMed Central

    Lund, Troy C.; Patrinostro, Xiaobai; Kramer, Ashley C.; Stadem, Paul; Higgins, LeeAnn; Markowski, Todd W.; Wroblewski, Matt S.; Lidke, Diane S.; Tolar, Jakub; Blazar, Bruce R.

    2014-01-01

    There is accumulating evidence that mesenchymal stem cells (MSC) have their origin as perivascular cells (PVC) in vivo, but precisely identifying them has been a challenge, as they have no single definitive marker and are rare. We have developed a fluorescent transgenic vertebrate model in which PVC can be visualized in vivo based upon sdf1 expression in the zebrafish. Prospective isolation and culture of sdf1DsRed PVC demonstrated properties consistent with MSC including prototypical cell surface marker expression; mesodermal differentiation into adipogenic, osteogenic and chondrogenic lineages; and the ability to support hematopoietic cells. Global proteomic studies performed by 2-dimensional liquid chromatography and tandem mass spectrometry revealed a high degree of similarity to human MSC and discovery of novel markers (CD99, CD151 and MYOF) that were previously unknown to be expressed by hMSC. Dynamic in vivo imaging during fin regeneration showed that PVC may arise from undifferentiated mesenchyme providing evidence of a PVC – MSC relationship. This is the first model, established in zebrafish, in which MSC can be visualized in vivo and will allow us to better understand their function in a native environment. PMID:24905975

  17. Perivascular epithelioid cell tumour of the vagina in an 8 year old girl.

    PubMed

    Ong, Lin Yin; Hwang, Wei Sek; Wong, Adelina; Chan, Mei Yoke; Chui, Chan Hon

    2007-03-01

    Perivascular epithelioid cell tumor (PEComa) is a rare mesenchymal tumor with an unpredictable natural history. We present the first reported case of PEComa of the vagina diagnosed in an 8-year-old girl. This was initially diagnosed on biopsy as an embryonal rhabdomyosarcoma, and the patient underwent 3 cycles of chemotherapy according to the Mesenchymal Malignant Tumour 1989 protocol. A repeat scan, however, revealed an increase in tumor size. Total resection was achieved via a transvaginal (vertical sleeve) partial vaginectomy. The resected tumor had the typical appearance of a PEComa. Immunostains showed positive staining of tumor cells for HMB45, neuron-specific enolase, and calponin but were negative for S100 protein, melaninA, chromogranin, smooth muscle actin, desmin, caldesmon, epithelial membrane antigen, AE1/3, and synaptophysin. Six months after surgery, she remains free of tumor and is on follow-up with regular local examinations under anesthesia and computed tomography scans. Our case highlights the importance of an accurate initial diagnosis, and we stress the importance of regular surveillance over a significant period. PMID:17336201

  18. Gene transfer corrects acute GM2 gangliosidosis--potential therapeutic contribution of perivascular enzyme flow.

    PubMed

    Cachón-González, M Begoña; Wang, Susan Z; McNair, Rosamund; Bradley, Josephine; Lunn, David; Ziegler, Robin; Cheng, Seng H; Cox, Timothy M

    2012-08-01

    The GM2 gangliosidoses are fatal lysosomal storage diseases principally affecting the brain. Absence of β-hexosaminidase A and B activities in the Sandhoff mouse causes neurological dysfunction and recapitulates the acute Tay-Sachs (TSD) and Sandhoff diseases (SD) in infants. Intracranial coinjection of recombinant adeno-associated viral vectors (rAAV), serotype 2/1, expressing human β-hexosaminidase α (HEXA) and β (HEXB) subunits into 1-month-old Sandhoff mice gave unprecedented survival to 2 years and prevented disease throughout the brain and spinal cord. Classical manifestations of disease, including spasticity-as opposed to tremor-ataxia-were resolved by localized gene transfer to the striatum or cerebellum, respectively. Abundant biosynthesis of β-hexosaminidase isozymes and their global distribution via axonal, perivascular, and cerebrospinal fluid (CSF) spaces, as well as diffusion, account for the sustained phenotypic rescue-long-term protein expression by transduced brain parenchyma, choroid plexus epithelium, and dorsal root ganglia neurons supplies the corrective enzyme. Prolonged survival permitted expression of cryptic disease in organs not accessed by intracranial vector delivery. We contend that infusion of rAAV into CSF space and intraparenchymal administration by convection-enhanced delivery at a few strategic sites will optimally treat neurodegeneration in many diseases affecting the nervous system. PMID:22453766

  19. The effects of human umbilical cord perivascular cells on rat hepatocyte structure and functional polarity.

    PubMed

    Gómez-Aristizábal, Alejandro; Davies, John Edward

    2013-06-01

    Hepatocyte culture is a useful tool for the study of their biology and the development of bioartificial livers. However, many challenges have to be overcome since hepatocytes rapidly lose their normal phenotype in vitro. We have recently demonstrated that human umbilical cord perivascular cells (HUCPVCs) are able to provide support to hepatocytes. In the present study we go further into exploring the effects that HUCPVCs have in the functional polarization, and both the internal and external organization, of hepatocytes. Also, we investigate HUCPVC-hepatocyte crosstalk by tracking both the effects of HUCPVCs on hepatocyte transcription factors and those of hepatocytes on the expression of hepatotrophic factors in HUCPVCs. Our results show that HUCPVCs maintain the functional polarity of hepatocytes ex vivo, as judged by the secretion of fluorescein into bile canaliculi, for at least 40 days. Transmission electron microscopy revealed that hepatocytes in coculture organize in an organoid-like structure embedded in extracellular matrix surrounded by HUCPVCs. In coculture, hepatocytes displayed a higher expression of C/EBPα, implicated in maintenance of the mature hepatocyte phenotype, and HUCPVCs upregulated hepatocyte growth factor and Jagged1 indicating that these genes may play important roles in HUCPVC-hepatocyte interactions.

  20. Gene Transfer Corrects Acute GM2 Gangliosidosis—Potential Therapeutic Contribution of Perivascular Enzyme Flow

    PubMed Central

    Cachón-González, M Begoña; Wang, Susan Z; McNair, Rosamund; Bradley, Josephine; Lunn, David; Ziegler, Robin; Cheng, Seng H; Cox, Timothy M

    2012-01-01

    The GM2 gangliosidoses are fatal lysosomal storage diseases principally affecting the brain. Absence of β-hexosaminidase A and B activities in the Sandhoff mouse causes neurological dysfunction and recapitulates the acute Tay–Sachs (TSD) and Sandhoff diseases (SD) in infants. Intracranial coinjection of recombinant adeno-associated viral vectors (rAAV), serotype 2/1, expressing human β-hexosaminidase α (HEXA) and β (HEXB) subunits into 1-month-old Sandhoff mice gave unprecedented survival to 2 years and prevented disease throughout the brain and spinal cord. Classical manifestations of disease, including spasticity—as opposed to tremor-ataxia—were resolved by localized gene transfer to the striatum or cerebellum, respectively. Abundant biosynthesis of β-hexosaminidase isozymes and their global distribution via axonal, perivascular, and cerebrospinal fluid (CSF) spaces, as well as diffusion, account for the sustained phenotypic rescue—long-term protein expression by transduced brain parenchyma, choroid plexus epithelium, and dorsal root ganglia neurons supplies the corrective enzyme. Prolonged survival permitted expression of cryptic disease in organs not accessed by intracranial vector delivery. We contend that infusion of rAAV into CSF space and intraparenchymal administration by convection-enhanced delivery at a few strategic sites will optimally treat neurodegeneration in many diseases affecting the nervous system. PMID:22453766

  1. Hoxb5 marks long-term haematopoietic stem cells revealing a homogenous perivascular niche

    PubMed Central

    Chen, James Y.; Miyanishi, Masanori; Wang, Sean K.; Yamazaki, Satoshi; Sinha, Rahul; Kao, Kevin S.; Nakauchi, Hiromitsu; Weissman, Irving L.

    2016-01-01

    The hematopoietic stem cell (HSC) is arguably the most extensively characterized tissue stem cell. Since its identification by prospective isolation1, complex multi-parameter flow cytometric isolation of phenotypic subsets has facilitated studies on many aspects of HSC biology including, self-renewal2–4, differentiation, aging, niche5, and diversity6–8. Here we demonstrate by unbiased multi-step screening, identification of a single gene, Hoxb5 (homeobox B5 also known as Hox-2.1), whose expression in the bone marrow (BM) is limited to the long-term HSC (LT-HSC) in mice. Utilizing a single-color tri-mCherry reporter mouse driven by endogenous Hoxb5 regulation, only the Hoxb5-positive HSCs exhibit long-term reconstitution capacity after transplantation in primary transplant recipients, and critically, in secondary recipients. Only 7–35% of various previously defined immunophenotypic HSCs are LT-HSCs. Finally, by in situ imaging of mouse BM, we show that >94% of LT-HSC (Hoxb5+) are directly attached to VE-cadherin-positive cells, implicating a perivascular space as a near homogenous localization of the LT-HSC. PMID:26863982

  2. Dual Roles for Perivascular Macrophages in Immune-to-Brain Signaling

    PubMed Central

    Serrats, Jordi; Schiltz, Jennifer C.; García-Bueno, Borja; van Rooijen, Nico; Reyes, Teresa M.; Sawchenko, Paul E.

    2009-01-01

    Cytokines produced during infection/inflammation activate adaptive CNS responses, including acute stress responses mediated by the hypothalamo-pituitary-adrenal (HPA) axis. The mechanisms by which cytokines engage HPA control circuitry remain unclear, though stimulated release of prostanoids from neighboring vascular cells has been implicated in this regard. How specific vascular cell types, endothelial cells (ECs) vs. perivascular cells (PVCs; a subset of brain-resident macrophages), participate in this response remains unsettled. We exploited the phagocytic activity of PVCs to deplete them in rats by central injection of a liposome-encapsulated pro-apoptotic drug. This manipulation abrogated CNS and hormonal indices of HPA activation under immune challenge conditions (interleukin-1; IL-1) that activated prostanoid synthesis only in PVCs, while enhancing these responses to stimuli (lipopolysaccaride; LPS) that engaged prostanoid production by ECs as well. Thus, PVCs provide both prostanoid-mediated drive to the HPA axis, and an anti-inflammatory action that constrains endothelial, and overall CNS, responses to inflammatory insults. PMID:20152116

  3. Malignant mesenteric perivascular epithelioid cell neoplasm presenting as an intra-abdominal fistula in a 49-year-old female.

    PubMed

    Kapur, Sakshi; Patel, Napoleon K; Levin, Miles B; Huang, Richard

    2014-01-01

    Perivascular epithelioid cell tumors are rare mesenchymal tumors arising from histologically and immunohistochemically distinctive perivascular epithelioid cells that express both myogenic and melanocytic markers. These tumors are known to arise from different organs in the body and usually have an unpredictable clinical course. We report a case of a 49-year-old female who presented with diffuse abdominal pain, fever, chills, and nonbilious vomiting for a day. Work-up revealed a mesenteric mass measuring 13.5 × 7.7 × 9.5 cm, arising in the mesentery of the hepatic flexure, with adjacent gas suggestive of fistularization into the right colon. An exploratory laparotomy with resection of the mesenteric mass was performed, and the initial histopathology results were compatible with either an adenocarcinoma or a sarcoma; however, because of poor differentiation it was difficult to make a definitive diagnosis. However, final histopathology results revealed a malignant perivascular epithelioid cell tumor (with reservation that a S100 negative metastatic melanoma must be excluded clinically). Following surgery the patient was started on everolimus, an m-TOR inhibitor, and has shown good response to this medication.

  4. Malignant Mesenteric Perivascular Epithelioid Cell Neoplasm Presenting as an Intra-Abdominal Fistula in a 49-Year-Old Female

    PubMed Central

    Patel, Napoleon K.; Levin, Miles B.

    2014-01-01

    Perivascular epithelioid cell tumors are rare mesenchymal tumors arising from histologically and immunohistochemically distinctive perivascular epithelioid cells that express both myogenic and melanocytic markers. These tumors are known to arise from different organs in the body and usually have an unpredictable clinical course. We report a case of a 49-year-old female who presented with diffuse abdominal pain, fever, chills, and nonbilious vomiting for a day. Work-up revealed a mesenteric mass measuring 13.5 × 7.7 × 9.5 cm, arising in the mesentery of the hepatic flexure, with adjacent gas suggestive of fistularization into the right colon. An exploratory laparotomy with resection of the mesenteric mass was performed, and the initial histopathology results were compatible with either an adenocarcinoma or a sarcoma; however, because of poor differentiation it was difficult to make a definitive diagnosis. However, final histopathology results revealed a malignant perivascular epithelioid cell tumor (with reservation that a S100 negative metastatic melanoma must be excluded clinically). Following surgery the patient was started on everolimus, an m-TOR inhibitor, and has shown good response to this medication. PMID:25114821

  5. Real-Time Imaging of Perivascular Transport of Nanoparticles During Convection Enhanced Delivery in the Rat Cortex

    PubMed Central

    Foley, Conor P.; Nishimura, Nozomi; Neeves, Keith B.; Schaffer, Chris B.; Olbricht., William L.

    2012-01-01

    Convection enhanced delivery (CED) is a promising technique for administering large therapeutics that do not readily cross the blood brain barrier to neural tissue. It is of vital importance to understand how large drug constructs move through neural tissue during CED to optimize construct and delivery parameters so that drugs are concentrated in the targeted tissue, with minimal leakage outside the targeted zone. Experiments have shown that liposomes, viral vectors, high molecular weight tracers, and nanoparticles infused into neural tissue localize in the perivascular spaces of blood vessels within the brain parenchyma. In this work, we used two-photon excited fluorescence microscopy to monitor the real-time distribution of nanoparticles infused in the cortex of live, anesthetized rats via CED. Fluorescent nanoparticles of 24-nm and 100-nm nominal diameters were infused into rat cortex through microfluidic probes. We found that perivascular spaces provide a high permeability path for rapid convective transport of large nanoparticles through tissue, and that the effects of perivascular spaces on transport are more significant for larger particles that undergo hindered transport through the extra cellular matrix. This suggests that the vascular topology of the target tissue volume must be considered when delivering large therapeutic constructs via CED. PMID:22009318

  6. Perivascular Stem Cells Diminish Muscle Atrophy and Retain Viability in a Rotator Cuff Tear Model

    PubMed Central

    Eliasberg, Claire; Jensen, Andrew; Dar, Ayelet; Kowalski, Tomasz J.; Murray, Iain; Khan, Adam Z.; Natsuhara, Kyle; Garagozlo, Cameron; McAllister, David R.; Petrigliano, Frank A.

    2016-01-01

    Objectives: Rotator cuff tears (RCTs) are a common cause of shoulder pain and often necessitate surgical repair. Muscle changes including atrophy, fibrosis, and fatty degeneration can develop after RCTs, which may compromise surgical repair and clinical outcomes. Lipoaspirate-derived human perivascular stem cells (PSCs) have demonstrated myogenic and angiogenic potential in other small animal models of muscle injury. We hypothesized that the administration of PSCs following massive RCTs may help to diminish these muscle changes in a small animal model. Methods: A total of 90 immunodeficient mice were used (15 groups, N=6). Each was assigned to one of three surgical groups: i) sham, ii) supraspinatus and infraspinatus tendon transection (TT), or iii) TT and suprascapular nerve denervation (TT+DN). PSCs were harvested from human lipoaspirate and sorted using fluorescence-activated cell sorting into small blood vessel residing pericytes (CD146+ CD34- CD45- CD31-) and large blood perivascular adventitial cells (CD146- CD34+ CD45- CD31-). Mice received either a) no injection, b) saline injection, c) pericyte injection, or d) adventitial cell injection at the time of the index procedure or at two weeks following index surgery. The supraspinatus muscles were harvested six weeks after the index procedure. Muscle atrophy was assessed by measuring percent wet muscle weight change for each sample. Muscle fiber cross-sectional area (CSA), fibrosis, and fatty degeneration were analyzed using Image J™. Additionally, pericytes and adventitial cells were transduced with a luciferase-containing construct. Animals were given injections of luciferin and imaged using IVIS to track in vivo bioluminescence following injections to assess cell viability. Results: Treatment with PSC injection after TT resulted in less wet weight loss and greater muscle fiber CSA than control groups (P<0.05). The TT+DN groups treated with PSC injections two weeks post-op also had less muscle weight loss

  7. Diosgenin regulates adipokine expression in perivascular adipose tissue and ameliorates endothelial dysfunction via regulation of AMPK.

    PubMed

    Chen, Yan; Xu, Xiaoshan; Zhang, Yuanyuan; Liu, Kang; Huang, Fang; Liu, Baolin; Kou, Junping

    2016-01-01

    Perivascular adipose tissue (PVAT) has been recognized as an active contributor to vascular function due to its paracrine effects on cells contained within vascular wall. The present study was designed to investigate the effect of diosgenin on adipokine expression in PVAT with emphasis on the regulation of endothelial function. Palmitic acid (PA) stimulation induced inflammation and dysregulation of adipokine expression in PVAT. Diosgenin treatment inhibited IKKβ phosphorylation and downregulated mRNA expressions of proinflammatory cytokines/proteins including tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), monocyte chemoattractant protein (MCP-1), and inducible nitric oxide synthase (iNOS), while reduced gene expressions for adiponectin, PPARγ, and arginase 1 (Arg-1) were reversed by diosgenin treatment. Diosgenin enhanced AMPK phosphorylation under basal and inflammatory conditions in PVAT, whereas knockdown of AMPK by SiRNA diminished its modulatory effect, indicating that diosgenin inhibited inflammation in an AMPK-dependent manner. We prepared conditioned medium from PA-stimulated PVAT to induce endothelial dysfunction and found that pre-treatment of PVAT with diosgenin effectively restored the loss of ACh-induced vasodilation and increased eNOS phosphorylation in rat aorta. High-fat diet feeding in rats induced inflammation in PVAT and the impairment of endothelium-dependent vasodilation, whereas these alterations were prevented by oral administration of diosgenin at doses of 20 and 40 mg/kg. In conclusion, the obtained data showed that diosgenin ameliorated inflammation-associated adipokine dysregulation, and thereby prevented endothelial dysfunction. Our findings would shed a novel insight into the potential mechanism by which diosgenin protected endothelial function against inflammatory insult. PMID:26277096

  8. Cathepsin K expression in the spectrum of perivascular epithelioid cell (PEC) lesions of the kidney.

    PubMed

    Martignoni, Guido; Bonetti, Franco; Chilosi, Marco; Brunelli, Matteo; Segala, Diego; Amin, Mahul B; Argani, Pedram; Eble, John N; Gobbo, Stefano; Pea, Maurizio

    2012-01-01

    The perivascular epithelioid cell (PEC) is a unique cell type coexpressing contractile proteins (mainly α-smooth muscle actin), melanocytic markers, including microphthalmia-associated transcription factor (MITF), and estrogen and progesterone receptors. It is constantly present in a group of tumors called PEComas. Renal PEComas include the common angiomyolipoma as well as less common lesions such as microscopic angiomyolipoma, intraglomerular lesions, angiomyolipoma with epithelial cysts, epithelioid angiomyolipoma, oncocytoma-like angiomyolipoma and lymphangioleiomyomatosis of the renal sinus. It has been demonstrated that most of these lesions are determined by mutations affecting genes of the tuberous sclerosis complex, tuberous sclerosis 1 (TSC1) and tuberous sclerosis 2 (TSC2), with eventual deregulation of the RHEB/MTOR/RPS6KB2 pathway, and it has been observed that some PEComas regressed during sirolimus therapy, an MTOR inhibitor. Recently, overexpression of MITF has been related to the expression of the papain-like cysteine protease cathepsin K in osteoclasts where it has inhibited MTOR. The aim of this study is to evaluate cathepsin K immunohistochemically in the entire spectrum of PEComa lesions in the kidney. The study population consisted of 84 renal PEComa lesions, including 5 composed predominantly of fat (lipoma-like angiomyolipoma), 15 almost exclusively composed of spindle-shaped smooth muscle cells (leiomyoma-like angiomyolipoma) and 31 common angiomyolipomas composed of a mixture of fat, spindle and epithelioid smooth muscle cells, and abnormal thick-walled blood vessels, 15 microscopic angiomyolipomas, 5 intraglomerular lesions, 2 oncocytoma-like angiomyolipomas, 8 epithelioid angiomyolipomas, 2 angiomyolipomas with epithelial cysts and 1 example of lymphangioleiomyomatosis of the renal sinus. In all of the renal PEComas, cathepsin K was found to be constantly and strongly expressed and seems to be a more powerful marker than other commonly

  9. Alterations in perivascular innervation function in mesenteric arteries from offspring of diabetic rats

    PubMed Central

    de Queiroz, D B; Sastre, E; Caracuel, L; Callejo, M; Xavier, F E; Blanco-Rivero, J; Balfagón, G

    2015-01-01

    Background and Purpose We have reported that exposure to a diabetic intrauterine environment during pregnancy increases blood pressure in adult offspring, but the mechanisms involved are not completely understood. This study was designed to analyse a possible role of perivascular sympathetic and nitrergic innervation in the superior mesenteric artery (SMA) in this effect. Experimental Approach Diabetes was induced in pregnant Wistar rats by a single injection of streptozotocin. Endothelium-denuded vascular rings from the offspring of control (O-CR) and diabetic rats (O-DR) were used. Vasomotor responses to electrical field stimulation (EFS), NA and the NO donor DEA-NO were studied. The expressions of neuronal NOS (nNOS) and phospho-nNOS (P-nNOS) and release of NA, ATP and NO were determined. Sympathetic and nitrergic nerve densities were analysed by immunofluorescence. Key Results Blood pressure was higher in O-DR animals. EFS-induced vasoconstriction was greater in O-DR animals. This response was decreased by phentolamine more in O-DR animals than their controls. L-NAME increased EFS-induced vasoconstriction more strongly in O-DR than in O-CR segments. Vasomotor responses to NA or DEA-NO were not modified. NA, ATP and NO release was increased in segments from O-DR. nNOS expression was not modified, whereas P-nNOS expression was increased in O-DR. Sympathetic and nitrergic nerve densities were similar in both experimental groups. Conclusions and Implications The activity of sympathetic and nitrergic innervation is increased in SMA from O-DR animals. The net effect is an increase in EFS-induced contractions in these animals. These effects may contribute to the increased blood pressure observed in the offspring of diabetic rats. PMID:26177571

  10. Alterations in Perivascular Sympathetic and Nitrergic Innervation Function Induced by Late Pregnancy in Rat Mesenteric Arteries

    PubMed Central

    Caracuel, Laura; Callejo, María; Balfagón, Gloria

    2015-01-01

    Background and Purpose We investigated whether pregnancy was associated with changed function in components of perivascular mesenteric innervation and the mechanism/s involved. Experimental Approach We used superior mesenteric arteries from female Sprague-Dawley rats divided into two groups: control rats (in oestrous phase) and pregnant rats (20 days of pregnancy). Modifications in the vasoconstrictor response to electrical field stimulation (EFS) were analysed in the presence/absence of phentolamine (alpha-adrenoceptor antagonist) or L-NAME (nitric oxide synthase-NOS- non-specific inhibitor). Vasomotor responses to noradrenaline (NA), and to NO donor DEA-NO were studied, NA and NO release measured and neuronal NOS (nNOS) expression/activation analysed. Key Results EFS induced a lower frequency-dependent contraction in pregnant than in control rats. Phentolamine decreased EFS-induced vasoconstriction in segments from both experimental groups, but to a greater extent in control rats. EFS-induced vasoconstriction was increased by L-NAME in arteries from both experimental groups. This increase was greater in segments from pregnant rats. Pregnancy decreased NA release while increasing NO release. nNOS expression was not modified but nNOS activation was increased by pregnancy. Pregnancy decreased NA-induced vasoconstriction response and did not modify DEA-NO-induced vasodilation response. Conclusions and Implications Neural control of mesenteric vasomotor tone was altered by pregnancy. Diminished sympathetic and enhanced nitrergic components both contributed to the decreased vasoconstriction response to EFS during pregnancy. All these changes indicate the selective participation of sympathetic and nitrergic innervations in vascular adaptations produced during pregnancy. PMID:25951331

  11. Different Anti-Contractile Function and Nitric Oxide Production of Thoracic and Abdominal Perivascular Adipose Tissues.

    PubMed

    Victorio, Jamaira A; Fontes, Milene T; Rossoni, Luciana V; Davel, Ana P

    2016-01-01

    Divergent phenotypes between the perivascular adipose tissue (PVAT) surrounding the abdominal and the thoracic aorta might be implicated in regional aortic differences, such as susceptibility to atherosclerosis. Although PVAT of the thoracic aorta exhibits anti-contractile function, the role of PVAT in the regulation of the vascular tone of the abdominal aorta is not well defined. In the present study, we compared the anti-contractile function, nitric oxide (NO) availability, and reactive oxygen species (ROS) formation in PVAT and vessel walls of abdominal and thoracic aorta. Abdominal and thoracic aortic tissue from male Wistar rats were used to perform functional and molecular experiments. PVAT reduced the contraction evoked by phenylephrine in the absence and presence of endothelium in the thoracic aorta, whereas this anti-contractile effect was not observed in the abdominal aorta. Abdominal PVAT exhibited a reduction in endothelial NO synthase (eNOS) expression compared with thoracic PVAT, without differences in eNOS expression in the vessel walls. In agreement with this result, NO production evaluated in situ using 4,5-diaminofluorescein was less pronounced in abdominal compared with thoracic aortic PVAT, whereas no significant difference was observed for endothelial NO production. Moreover, NOS inhibition with L-NAME enhanced the phenylephrine-induced contraction in endothelial-denuded rings with PVAT from thoracic but not abdominal aorta. ROS formation and lipid peroxidation products evaluated through the quantification of hydroethidine fluorescence and 4-hydroxynonenal adducts, respectively, were similar between PVAT and vessel walls from the abdominal and thoracic aorta. Extracellular superoxide dismutase (SOD) expression was similar between the vessel walls and PVAT of the abdominal and thoracic aorta. However, Mn-SOD levels were reduced, while CuZn-SOD levels were increased in abdominal PVAT compared with thoracic aortic PVAT. In conclusion, our results

  12. Different Anti-Contractile Function and Nitric Oxide Production of Thoracic and Abdominal Perivascular Adipose Tissues

    PubMed Central

    Victorio, Jamaira A.; Fontes, Milene T.; Rossoni, Luciana V.; Davel, Ana P.

    2016-01-01

    Divergent phenotypes between the perivascular adipose tissue (PVAT) surrounding the abdominal and the thoracic aorta might be implicated in regional aortic differences, such as susceptibility to atherosclerosis. Although PVAT of the thoracic aorta exhibits anti-contractile function, the role of PVAT in the regulation of the vascular tone of the abdominal aorta is not well defined. In the present study, we compared the anti-contractile function, nitric oxide (NO) availability, and reactive oxygen species (ROS) formation in PVAT and vessel walls of abdominal and thoracic aorta. Abdominal and thoracic aortic tissue from male Wistar rats were used to perform functional and molecular experiments. PVAT reduced the contraction evoked by phenylephrine in the absence and presence of endothelium in the thoracic aorta, whereas this anti-contractile effect was not observed in the abdominal aorta. Abdominal PVAT exhibited a reduction in endothelial NO synthase (eNOS) expression compared with thoracic PVAT, without differences in eNOS expression in the vessel walls. In agreement with this result, NO production evaluated in situ using 4,5-diaminofluorescein was less pronounced in abdominal compared with thoracic aortic PVAT, whereas no significant difference was observed for endothelial NO production. Moreover, NOS inhibition with L-NAME enhanced the phenylephrine-induced contraction in endothelial-denuded rings with PVAT from thoracic but not abdominal aorta. ROS formation and lipid peroxidation products evaluated through the quantification of hydroethidine fluorescence and 4-hydroxynonenal adducts, respectively, were similar between PVAT and vessel walls from the abdominal and thoracic aorta. Extracellular superoxide dismutase (SOD) expression was similar between the vessel walls and PVAT of the abdominal and thoracic aorta. However, Mn-SOD levels were reduced, while CuZn-SOD levels were increased in abdominal PVAT compared with thoracic aortic PVAT. In conclusion, our results

  13. Loss of anti-contractile effect of perivascular adipose tissue in offspring of obese rats

    PubMed Central

    Zaborska, K E; Wareing, M; Edwards, G; Austin, C

    2016-01-01

    Rationale: Maternal obesity pre-programmes offspring to develop obesity and associated cardiovascular disease. Perivascular adipose tissue (PVAT) exerts an anti-contractile effect on the vasculature, which is reduced in hypertension and obesity. Objective: The objective of this study was to determine whether maternal obesity pre-programmes offspring to develop PVAT dysfunction in later life. Methods: Female Sprague–Dawley rats were fed a diet containing 10% (control) or 45% fat (high fat diet, HFD) for 12 weeks prior to mating and during pregnancy and lactation. Male offspring were killed at 12 or 24 weeks of age and tension in PVAT-intact or -denuded mesenteric artery segments was measured isometrically. Concentration–response curves were constructed to U46619 and norepinephrine. Results: Only 24-week-old HFD offspring were hypertensive (P<0.0001), although the anti-contractile effect of PVAT was lost in vessels from HFD offspring of each age. Inhibition of nitric oxide (NO) synthase with 100 μM l-NMMA attenuated the anti-contractile effect of PVAT and increased contractility of PVAT-denuded arteries (P<0.05, P<0.0001). The increase in contraction was smaller in PVAT-intact than PVAT-denuded vessels from 12-week-old HFD offspring, suggesting decreased PVAT-derived NO and release of a contractile factor (P<0.07). An additional, NO-independent effect of PVAT was evident only in norepinephrine-contracted vessels. Activation of AMP-activated kinase (with 10 μM A769662) was anti-contractile in PVAT-denuded (P<0.0001) and -intact (P<0.01) vessels and was due solely to NO in controls; the AMPK effect was similar in HFD offspring vessels (P<0.001 and P<0.01, respectively) but was partially NO-independent. Conclusions: The diminished anti-contractile effects of PVAT in offspring of HFD dams are primarily due to release of a PVAT-derived contractile factor and reduced NO bioavailability. PMID:27102050

  14. Human perivascular stem cells show enhanced osteogenesis and vasculogenesis with Nel-like molecule I protein.

    PubMed

    Askarinam, Asal; James, Aaron W; Zara, Janette N; Goyal, Raghav; Corselli, Mirko; Pan, Angel; Liang, Pei; Chang, Le; Rackohn, Todd; Stoker, David; Zhang, Xinli; Ting, Kang; Péault, Bruno; Soo, Chia

    2013-06-01

    An ideal mesenchymal stem cell (MSC) source for bone tissue engineering has yet to be identified. Such an MSC population would be easily harvested in abundance, with minimal morbidity and with high purity. Our laboratories have identified perivascular stem cells (PSCs) as a candidate cell source. PSCs are readily isolatable through fluorescent-activated cell sorting from adipose tissue and have been previously shown to be indistinguishable from MSCs in the phenotype and differentiation potential. PSCs consist of two distinct cell populations: (1) pericytes (CD146+, CD34-, and CD45-), which surround capillaries and microvessels, and (2) adventitial cells (CD146-, CD34+, and CD45-), found within the tunica adventitia of large arteries and veins. We previously demonstrated the osteogenic potential of pericytes by examining pericytes derived from the human fetal pancreas, and illustrated their in vivo trophic and angiogenic effects. In the present study, we used an intramuscular ectopic bone model to develop the translational potential of our original findings using PSCs (as a combination of pericytes and adventitial cells) from human white adipose tissue. We evaluated human PSC (hPSC)-mediated bone formation and vascularization in vivo. We also examined the effects of hPSCs when combined with the novel craniosynostosis-associated protein, Nel-like molecule I (NELL-1). Implants consisting of the demineralized bone matrix putty combined with NELL-1 (3 μg/μL), hPSC (2.5×10(5) cells), or hPSC+NELL-1, were inserted in the bicep femoris of SCID mice. Bone growth was evaluated using microcomputed tomography, histology, and immunohistochemistry over 4 weeks. Results demonstrated the osteogenic potential of hPSCs and the additive effect of hPSC+NELL-1 on bone formation and vasculogenesis. Comparable osteogenesis was observed with NELL-1 as compared to the more commonly used bone morphogenetic protein-2. Next, hPSCs induced greater implant vascularization than the unsorted

  15. Nerve growth factor facilitates redistribution of adrenergic and non-adrenergic non-cholinergic perivascular nerves injured by phenol in rat mesenteric resistance arteries.

    PubMed

    Yokomizo, Ayako; Takatori, Shingo; Hashikawa-Hobara, Narumi; Goda, Mitsuhiro; Kawasaki, Hiromu

    2016-01-01

    We previously reported that nerve growth factor (NGF) facilitated perivascular sympathetic neuropeptide Y (NPY)- and calcitonin gene-related peptide (CGRP)-containing nerves injured by the topical application of phenol in the rat mesenteric artery. We also demonstrated that mesenteric arterial nerves were distributed into tyrosine hydroxylase (TH)-, substance P (SP)-, and neuronal nitric oxide synthase (nNOS)-containing nerves, which had axo-axonal interactions. In the present study, we examined the effects of NGF on phenol-injured perivascular nerves, including TH-, NPY-, nNOS-, CGRP-, and SP-containing nerves, in rat mesenteric arteries in more detail. Wistar rats underwent the in vivo topical application of 10% phenol to the superior mesenteric artery, proximal to the abdominal aorta, under pentobarbital-Na anesthesia. The distribution of perivascular nerves in the mesenteric arteries of the 2nd to 3rd-order branches isolated from 8-week-old Wistar rats was investigated immunohistochemically using antibodies against TH-, NPY-, nNOS-, CGRP-, and SP-containing nerves. The topical phenol treatment markedly reduced the density of all nerves in these arteries. The administration of NGF at a dose of 20µg/kg/day with an osmotic pump for 7 days significantly increased the density of all perivascular nerves over that of sham control levels. These results suggest that NGF facilitates the reinnervation of all perivascular nerves injured by phenol in small resistance arteries.

  16. Nerve growth factor facilitates redistribution of adrenergic and non-adrenergic non-cholinergic perivascular nerves injured by phenol in rat mesenteric resistance arteries.

    PubMed

    Yokomizo, Ayako; Takatori, Shingo; Hashikawa-Hobara, Narumi; Goda, Mitsuhiro; Kawasaki, Hiromu

    2016-01-01

    We previously reported that nerve growth factor (NGF) facilitated perivascular sympathetic neuropeptide Y (NPY)- and calcitonin gene-related peptide (CGRP)-containing nerves injured by the topical application of phenol in the rat mesenteric artery. We also demonstrated that mesenteric arterial nerves were distributed into tyrosine hydroxylase (TH)-, substance P (SP)-, and neuronal nitric oxide synthase (nNOS)-containing nerves, which had axo-axonal interactions. In the present study, we examined the effects of NGF on phenol-injured perivascular nerves, including TH-, NPY-, nNOS-, CGRP-, and SP-containing nerves, in rat mesenteric arteries in more detail. Wistar rats underwent the in vivo topical application of 10% phenol to the superior mesenteric artery, proximal to the abdominal aorta, under pentobarbital-Na anesthesia. The distribution of perivascular nerves in the mesenteric arteries of the 2nd to 3rd-order branches isolated from 8-week-old Wistar rats was investigated immunohistochemically using antibodies against TH-, NPY-, nNOS-, CGRP-, and SP-containing nerves. The topical phenol treatment markedly reduced the density of all nerves in these arteries. The administration of NGF at a dose of 20µg/kg/day with an osmotic pump for 7 days significantly increased the density of all perivascular nerves over that of sham control levels. These results suggest that NGF facilitates the reinnervation of all perivascular nerves injured by phenol in small resistance arteries. PMID:26671004

  17. Minute perivascular epithelioid cell (PEC) nests in the abdominal lymph nodes--a putative precursor of PEComa.

    PubMed

    Nagasaka, Toru; Murakami, Yoshiko; Sasaki, Eiichi; Hosoda, Waki; Nakanishi, Toru; Yatabe, Yasushi

    2015-04-01

    A perivascular epithelioid cell tumor (PEComa) is a peculiar growth defined as a mesenchymal tumor composed of histologically and immunohistochemically distinct perivascular epithelioid cells (PECs). Because neither normal counterparts nor precursor lesions of PEComa have been identified, we examined minute PEC nests, ranged from 0.8 mm to 10 mm, to investigate the possible origin of the PEComa. We examined a total of 80 677 para-aortic and pelvic lymph nodes that were systematically dissected from 1656 patients for gynecological malignancies. The identified lesions were confirmed immunohistochemically with multiple PEC markers, including smooth muscle actin, HMB45, melan-A, MiTF, ER and PgR. A total of 66 minute PEC nests were found in 21 patients (1.3% of the total population) with an average frequency of 3.1 lesions per patient. In cases of multiple involvement, 11 of 13 nests were located at the same level of multiple lymph node or on continuous levels. The lesions were preferentially distributed at the level of para-aortic and high pelvic lymph nodes. All nests were positive for actin and HMB45, whereas the other markers were positive with varying frequencies. The minute PEC nests may be associated with the possible normal counterpart of PEComas.

  18. Isolation and culture of endothelial cells, pericytes and perivascular resident macrophage-like melanocytes from the young mouse ear

    PubMed Central

    Neng, Lingling; Zhang, Wenjing; Hassan, Ahmed; Zemla, Marcin; Kachelmeier, Allan; Fridberger, Anders; Auer, Manfred; Shi, Xiaorui

    2013-01-01

    This protocol describes a growth medium–based approach for obtaining cochlear endothelial cells (ECs), pericytes (PCs) and perivascular resident macrophage-like melanocytes (PVM/Ms) from the stria vascularis of mice aged between P10 and P15 (P, postnatal day). The procedure does not involve mechanical or enzymatic digestion of the sample tissue. Explants of stria vascularis, ‘mini-chips’, are selectively cultured in growth medium, and primary cell lines are obtained in 7–10 d. The method is simple and reliable, and it provides high-quality ECs, PVM/Ms and PCs with a purity >90% after two passages. This protocol is suitable for producing primary culture cells from organs and tissues of small volume and high anatomical complexity, such as the inner ear capillaries. The highly purified primary cell lines enable cell culture–based in vitro modeling of cell-cell interactions, barrier control function and drug action. PMID:23493068

  19. Markers of fibroblast-rich tumor stroma and perivascular cells in serous ovarian cancer: Inter- and intra-patient heterogeneity and impact on survival

    PubMed Central

    Corvigno, Sara; Wisman, G. Bea A.; Mezheyeuski, Artur; van der Zee, Ate G.J.; Nijman, Hans W.; Åvall-Lundqvist, Elisabeth; Östman, Arne; Dahlstrand, Hanna

    2016-01-01

    Inter- and intra-patient variations in tumor microenvironment of serous ovarian cancer are largely unexplored. We aimed to explore potential co-regulation of tumor stroma characteristics, analyze their concordance in primary and metastatic lesions, and study their impact on survival. A tissue microarray (TMA) with 186 tumors and 91 matched metastases was subjected to immunohistochemistry double staining with endothelial cell marker CD34 and fibroblast and pericyte markers α-SMA, PDGFβR and desmin. Images were digitally analyzed to yield “metrics” related to vasculature and stroma features. Intra-case analyses showed that PDGFβR in perivascular cells and fibroblasts were strongly correlated. Similar findings were observed concerning α-SMA. Most stroma characteristics showed large variations in intra-case comparisons of primary tumors and metastasis. Large PDGFβR-positive stroma fraction and high PDGFβFR positive perivascular intensity were both significantly associated with shorter survival in uni- and multi-variate analyses (HR 1.7, 95% CI 1.1-2.5; HR 1.7, 95% CI 1.1-2.8). In conclusion, we found PDGFβR- and α-SMA-expression to be largely independent of each other but concordantly activated in perivascular cells and in fibroblasts within the primary tumor. Stromal characteristics differed between primary tumors and metastases. PDGFβR in perivascular cells and in fibroblasts may be novel prognostic markers in serous ovarian cancer. PMID:26918345

  20. Celecoxib, but not indomethacin, ameliorates the hypertensive and perivascular fibrotic actions of cyclosporine in rats: Role of endothelin signaling

    SciTech Connect

    El-Mas, Mahmoud M.; Helmy, Maged W.; Ali, Rabab M.; El-Gowelli, Hanan M.

    2015-04-01

    The immunosuppressant drug cyclosporine (CSA) is used with nonsteroidal antiinflammatory drugs (NSAIDs) in arthritic conditions. In this study, we investigated whether NSAIDs modify the deleterious hypertensive action of CSA and the role of endothelin (ET) receptors in this interaction. Pharmacologic, protein expression, and histopathologic studies were performed in rats to investigate the roles of endothelin receptors (ET{sub A}/ET{sub B}) in the hemodynamic interaction between CSA and two NSAIDs, indomethacin and celecoxib. Tail-cuff plethysmography measurements showed that CSA (20 mg kg{sup −1} day{sup −1}, 10 days) increased systolic blood pressure (SBP) and heart rate (HR). CSA hypertension was associated with renal perivascular fibrosis and divergent changes in immunohistochemical signals of renal arteriolar ET{sub A} (increases) and ET{sub B} (decreases) receptors. While these effects of CSA were preserved in rats treated concomitantly with indomethacin (5 mg kg{sup −1} day{sup −1}), celecoxib (10 mg kg{sup −1} day{sup −1}) abolished the pressor, tachycardic, and fibrotic effects of CSA and normalized the altered renal ET{sub A}/ET{sub B} receptor expressions. Selective blockade of ET{sub A} receptors by atrasentan (5 mg kg{sup −1} day{sup −1}) abolished the pressor response elicited by CSA or CSA plus indomethacin. Alternatively, BQ788 (ET{sub B} receptor blocker, 0.1 mg kg{sup −1} day{sup −1}) caused celecoxib-sensitive elevations in SBP and potentiated the pressor response evoked by CSA. Together, the improved renovascular fibrotic and endothelin receptor profile (ET{sub A} downregulation and ET{sub B} upregulation) mediate, at least partly, the protective effect of celecoxib against the hypertensive effect of CSA. Clinically, the use of celecoxib along with CSA in the management of arthritic conditions might provide hypertension-free regimen. - Highlights: • Chronic CSA causes hypertension and renal perivascular fibrosis in rats.

  1. Expression of the mannose receptor CD206 in HIV and SIV encephalitis: a phenotypic switch of brain perivascular macrophages with virus infection.

    PubMed

    Holder, Gerard E; McGary, Christopher M; Johnson, Edward M; Zheng, Rubo; John, Vijay T; Sugimoto, Chie; Kuroda, Marcelo J; Kim, Woong-Ki

    2014-12-01

    We examined the expression of the mannose receptor CD206 by perivascular macrophages (PVM) in normal human and monkey brains and in brains of HIV-infected humans and of monkeys infected with simian immunodeficiency virus (SIV). Depletion of brain PVM in SIV-infected monkeys by intrathecal injection of liposome-encapsulated bisphosphonates eliminated CD206-expressing cells in the brain, confirming their perivascular location and phagocytic capacity. In vivo labeling with bromodeoxyuridine in normal uninfected and SIV-infected macaques in combination with CD206 immunostaining revealed a CD206+-to-CD206- shift within pre-existing PVM during SIV brain infection and neuroinflammation. These findings identify CD206 as a unique marker of human and macaque PVM, and underscore the utility of this marker in studying the origin, turnover and functions of these cells in AIDS. PMID:25146376

  2. In Vitro Differentiation of First Trimester Human Umbilical Cord Perivascular Cells into Contracting Cardiomyocyte-Like Cells

    PubMed Central

    Szaraz, Peter; Librach, Matthew; Maghen, Leila; Iqbal, Farwah; Barretto, Tanya A.; Kenigsberg, Shlomit; Gauthier-Fisher, Andrée; Librach, Clifford L.

    2016-01-01

    Myocardial infarction (MI) causes an extensive loss of heart muscle cells and leads to congestive heart disease (CAD), the leading cause of mortality and morbidity worldwide. Mesenchymal stromal cell- (MSC-) based cell therapy is a promising option to replace invasive interventions. However the optimal cell type providing significant cardiac regeneration after MI is yet to be found. The aim of our study was to investigate the cardiomyogenic differentiation potential of first trimester human umbilical cord perivascular cells (FTM HUCPVCs), a novel, young source of immunoprivileged mesenchymal stromal cells. Based on the expression of cardiomyocyte markers (cTnT, MYH6, SIRPA, and CX43) FTM and term HUCPVCs achieved significantly increased cardiomyogenic differentiation compared to bone marrow MSCs, while their immunogenicity remained significantly lower as indicated by HLA-A and HLA-G expression and susceptibility to T cell mediated cytotoxicity. When applying aggregate-based differentiation, FTM HUCPVCs showed increased aggregate formation potential and generated contracting cells within 1 week of coculture, making them the first MSC type with this ability. Our results indicate that young FTM HUCPVCs have superior cardiomyogenic potential coupled with beneficial immunogenic properties when compared to MSCs of older tissue sources, suggesting that in vitro predifferentiation could be a potential strategy to increase their effectiveness in vivo. PMID:27123009

  3. Aging Exacerbates Obesity-Induced Oxidative Stress and Inflammation in Perivascular Adipose Tissue in Mice: A Paracrine Mechanism Contributing to Vascular Redox Dysregulation and Inflammation

    PubMed Central

    Bailey-Downs, Lora C.; Tucsek, Zsuzsanna; Toth, Peter

    2013-01-01

    Obesity in the elderly individuals is increasing at alarming rates and there is evidence suggesting that elderly individuals are more vulnerable to the deleterious cardiovascular effects of obesity than younger individuals. However, the specific mechanisms through which aging and obesity interact to promote the development of cardiovascular disease remain unclear. The present study was designed to test the hypothesis that aging exacerbates obesity-induced inflammation in perivascular adipose tissue, which contributes to increased vascular oxidative stress and inflammation in a paracrine manner. To test this hypothesis, we assessed changes in the secretome, reactive oxygen species production, and macrophage infiltration in periaortic adipose tissue of young (7 month old) and aged (24 month old) high-fat diet–fed obese C57BL/6 mice. High-fat diet–induced vascular reactive oxygen species generation significantly increased in aged mice, which was associated with exacerbation of endothelial dysfunction and vascular inflammation. In young animals, high-fat diet–induced obesity promoted oxidative stress in the perivascular adipose tissue, which was associated with a marked proinflammatory shift in the profile of secreted cytokines and chemokines. Aging exacerbated obesity-induced oxidative stress and inflammation and significantly increased macrophage infiltration in periaortic adipose tissue. Using cultured arteries isolated from young control mice, we found that inflammatory factors secreted from the perivascular fat tissue of obese aged mice promote significant prooxidative and proinflammatory phenotypic alterations in the vascular wall, mimicking the aging phenotype. Overall, our findings support an important role for localized perivascular adipose tissue inflammation in exacerbation of vascular oxidative stress and inflammation in aging, an effect that likely enhances the risk for development of cardiovascular diseases from obesity in the elderly individuals

  4. Vascular ADAM17 as a Novel Therapeutic Target in Mediating Cardiovascular Hypertrophy and Perivascular Fibrosis Induced by Angiotensin II.

    PubMed

    Takayanagi, Takehiko; Forrester, Steven J; Kawai, Tatsuo; Obama, Takashi; Tsuji, Toshiyuki; Elliott, Katherine J; Nuti, Elisa; Rossello, Armando; Kwok, Hang Fai; Scalia, Rosario; Rizzo, Victor; Eguchi, Satoru

    2016-10-01

    Angiotensin II (AngII) has been strongly implicated in hypertension and its complications. Evidence suggests the mechanisms by which AngII elevates blood pressure and enhances cardiovascular remodeling and damage may be distinct. However, the signal transduction cascade by which AngII specifically initiates cardiovascular remodeling, such as hypertrophy and fibrosis, remains insufficiently understood. In vascular smooth muscle cells, a metalloproteinase ADAM17 mediates epidermal growth factor receptor transactivation, which may be responsible for cardiovascular remodeling but not hypertension induced by AngII. Thus, the objective of this study was to test the hypothesis that activation of vascular ADAM17 is indispensable for vascular remodeling but not for hypertension induced by AngII. Vascular ADAM17-deficient mice and control mice were infused with AngII for 2 weeks. Control mice infused with AngII showed cardiac hypertrophy, vascular medial hypertrophy, and perivascular fibrosis. These phenotypes were prevented in vascular ADAM17-deficient mice independent of blood pressure alteration. AngII infusion enhanced ADAM17 expression, epidermal growth factor receptor activation, and endoplasmic reticulum stress in the vasculature, which were diminished in ADAM17-deficient mice. Treatment with a human cross-reactive ADAM17 inhibitory antibody also prevented cardiovascular remodeling and endoplasmic reticulum stress but not hypertension in C57Bl/6 mice infused with AngII. In vitro data further supported these findings. In conclusion, vascular ADAM17 mediates AngII-induced cardiovascular remodeling via epidermal growth factor receptor activation independent of blood pressure regulation. ADAM17 seems to be a unique therapeutic target for the prevention of hypertensive complications.

  5. Pharmacological activation of AMPK ameliorates perivascular adipose/endothelial dysfunction in a manner interdependent on AMPK and SIRT1.

    PubMed

    Sun, Yan; Li, Jia; Xiao, Na; Wang, Meng; Kou, Junping; Qi, Lianwen; Huang, Fang; Liu, Baolin; Liu, Kang

    2014-11-01

    Adipose and endothelial dysfunction is tightly associated with cardiovascular diseases in obesity and insulin resistance. Because perivascular adipose tissue (PVAT) surrounds vessels directly and influences vessel functions through paracrine effect, and AMP-activated protein kinase (AMPK) and sirtuin 1 (SIRT1) show similarities in modulation of metabolic pathway, we hypothesized that activation of AMPK and SIRT1 in PVAT might regulate the endothelial function in pathological settings. Thus, in this study, we focused on the regulation of AMPK and SIRT1 activities implicated in adipocytokine expression and endothelial homeostasis under inflammatory conditions by using salicylate, metformin, AICA riboside (AICAR) and resveratrol as AMPK activating agents. We prepared conditioned medium (CM) by stimulating PVAT with palmitic acid (PA) and observed the effects of AMPK activating agents on adipocytokine expression and vessel vasodilation in rats. Moreover, we explored the effects of resveratrol and metformin in fructose-fed rats. We observed that PA stimulation induced inflammation and dysregulation of adipocytokine expression accompanied with reduced AMPK activity and SIRT1 abundance in PVAT. AMPK activating agents inhibited NF-κB p65 phosphorylation and suppressed gene expression of pro-inflammatory adipocytokines, and upregulated adiponectin and PPARγ expression in PVAT in an AMPK/SIRT1-interdependent manner. Meanwhile, CM stimulation impaired endothelium-dependent vasodilation in response to acetylcholine (ACh). Pretreatment of CM with AMPK-activating agents enhanced eNOS phosphorylation in the aorta and restored the loss of endothelium-dependent vasodilation, whereas this action was abolished by co-treatment with AMPK inhibitor compound C or SIRT1 inhibitor nicotinamide. Long-term fructose-feeding in rats induced dysregulation of adipocytokine expression in PVAT and the loss of endothelium-dependent vasodilation, whereas these alterations were reversed by oral

  6. Quantifying Perivascular Sympathetic Innervation: Regional Differences in Male C57BL/6 Mice at 3 and 20 Months

    PubMed Central

    Long, Jennifer B.; Segal, Steven S.

    2009-01-01

    Perivascular sympathetic innervation density (PSID) is a key determinant of vasomotor responses to sympathetic nerve activity. However, total axonal length (for en passant neurotransmission) per vessel surface area has not been well defined, particularly while preserving 3-dimensional vascular structure. We developed a novel method for quantifying PSID using 3-dimensional anatomical reconstruction and compare a variety of blood vessels in Young (3 months) and Old (20 months) male C57BL/6 mice. Individual vessels were dissected and immunolabeled for tyrosine hydroxylase. The total length of fluorescent axons in defined vessel surface areas was quantified by mapping Z-stack images (magnification = 760×). For young mice, innervation densities (μm axon length/μm2 vessel surface area) in mesenteric (0.075 ± 0.002) and femoral (0.080 ± 0.003) arteries were greater (P<0.05) than mesenteric veins (0.052 ± 0.002) and gracilis muscle feed arteries (0.040 ± 0.002). Carotid arteries and gracilis muscle veins were not immunoreactive nor were there significant differences in PSID between Young and Old animals. We demonstrate a novel approach to quantify sympathetic innervation of the vasculature while preserving its 3-dimensional structure and document regional variation in PSID that persists with aging in mice. This analytical approach may used for quantifying PSID in other tissues that have superficial vessels which can be studied in situ or from which embedded vessels can be excised. With appropriate visualization of neuronal projections, it may also be applied to tissues that have other sources of superficial innervation. PMID:19651158

  7. Brief Report: Human Perivascular Stem Cells and Nel-Like Protein-1 Synergistically Enhance Spinal Fusion in Osteoporotic Rats.

    PubMed

    Lee, Soonchul; Zhang, Xinli; Shen, Jia; James, Aaron W; Chung, Choon G; Hardy, Reef; Li, Chenshuang; Girgius, Caroline; Zhang, Yulong; Stoker, David; Wang, Huiming; Wu, Benjamin M; Peault, Bruno; Ting, Kang; Soo, Chia

    2015-10-01

    Autologous bone grafts (ABGs) are considered as the gold standard for spinal fusion. However, osteoporotic patients are poor candidates for ABGs due to limited osteogenic stem cell numbers and function of the bone microenvironment. There is a need for stem cell-based spinal fusion of proven efficacy under either osteoporotic or nonosteoporotic conditions. The purpose of this study is to determine the efficacy of human perivascular stem cells (hPSCs), a population of mesenchymal stem cells isolated from adipose tissue, in the presence and absence of NELL-1, an osteogenic protein, for spinal fusion in the osteoporosis. Osteogenic differentiation of hPSCs with and without NELL-1 was tested in vitro. The results indicated that NELL-1 significantly increased the osteogenic potential of hPSCs in both osteoporotic and nonosteoporotic donors. Next, spinal fusion was performed by implanting scaffolds with regular or high doses of hPSCs, with or without NELL-1 in ovariectomized rats (n = 41). Regular doses of hPSCs or NELL-1 achieved the fusion rates of only 20%-37.5% by manual palpation. These regular doses had previously been shown to be effective in nonosteoporotic rat spinal fusion. Remarkably, the high dose of hPSCs+NELL-1 significantly improved the fusion rates among osteoporotic rats up to approximately 83.3%. Microcomputed tomography imaging and quantification further confirmed solid bony fusion with high dose hPSCs+NELL-1. Finally, histologically, direct in situ involvement of hPSCs in ossification was shown using undecalcified samples. To conclude, hPSCs combined with NELL-1 synergistically enhances spinal fusion in osteoporotic rats and has great potential as a novel therapeutic strategy for osteoporotic patients.

  8. Segmentation of perivascular spaces in 7T MR image using auto-context model with orientation-normalized features.

    PubMed

    Park, Sang Hyun; Zong, Xiaopeng; Gao, Yaozong; Lin, Weili; Shen, Dinggang

    2016-07-01

    Quantitative study of perivascular spaces (PVSs) in brain magnetic resonance (MR) images is important for understanding the brain lymphatic system and its relationship with neurological diseases. One of the major challenges is the accurate extraction of PVSs that have very thin tubular structures with various directions in three-dimensional (3D) MR images. In this paper, we propose a learning-based PVS segmentation method to address this challenge. Specifically, we first determine a region of interest (ROI) by using the anatomical brain structure and the vesselness information derived from eigenvalues of image derivatives. Then, in the ROI, we extract a number of randomized Haar features which are normalized with respect to the principal directions of the underlying image derivatives. The classifier is trained by the random forest model that can effectively learn both discriminative features and classifier parameters to maximize the information gain. Finally, a sequential learning strategy is used to further enforce various contextual patterns around the thin tubular structures into the classifier. For evaluation, we apply our proposed method to the 7T brain MR images scanned from 17 healthy subjects aged from 25 to 37. The performance is measured by voxel-wise segmentation accuracy, cluster-wise classification accuracy, and similarity of geometric properties, such as volume, length, and diameter distributions between the predicted and the true PVSs. Moreover, the accuracies are also evaluated on the simulation images with motion artifacts and lacunes to demonstrate the potential of our method in segmenting PVSs from elderly and patient populations. The experimental results show that our proposed method outperforms all existing PVS segmentation methods. PMID:27046107

  9. Vascular ADAM17 as a Novel Therapeutic Target in Mediating Cardiovascular Hypertrophy and Perivascular Fibrosis Induced by Angiotensin II.

    PubMed

    Takayanagi, Takehiko; Forrester, Steven J; Kawai, Tatsuo; Obama, Takashi; Tsuji, Toshiyuki; Elliott, Katherine J; Nuti, Elisa; Rossello, Armando; Kwok, Hang Fai; Scalia, Rosario; Rizzo, Victor; Eguchi, Satoru

    2016-10-01

    Angiotensin II (AngII) has been strongly implicated in hypertension and its complications. Evidence suggests the mechanisms by which AngII elevates blood pressure and enhances cardiovascular remodeling and damage may be distinct. However, the signal transduction cascade by which AngII specifically initiates cardiovascular remodeling, such as hypertrophy and fibrosis, remains insufficiently understood. In vascular smooth muscle cells, a metalloproteinase ADAM17 mediates epidermal growth factor receptor transactivation, which may be responsible for cardiovascular remodeling but not hypertension induced by AngII. Thus, the objective of this study was to test the hypothesis that activation of vascular ADAM17 is indispensable for vascular remodeling but not for hypertension induced by AngII. Vascular ADAM17-deficient mice and control mice were infused with AngII for 2 weeks. Control mice infused with AngII showed cardiac hypertrophy, vascular medial hypertrophy, and perivascular fibrosis. These phenotypes were prevented in vascular ADAM17-deficient mice independent of blood pressure alteration. AngII infusion enhanced ADAM17 expression, epidermal growth factor receptor activation, and endoplasmic reticulum stress in the vasculature, which were diminished in ADAM17-deficient mice. Treatment with a human cross-reactive ADAM17 inhibitory antibody also prevented cardiovascular remodeling and endoplasmic reticulum stress but not hypertension in C57Bl/6 mice infused with AngII. In vitro data further supported these findings. In conclusion, vascular ADAM17 mediates AngII-induced cardiovascular remodeling via epidermal growth factor receptor activation independent of blood pressure regulation. ADAM17 seems to be a unique therapeutic target for the prevention of hypertensive complications. PMID:27480833

  10. Design, fabrication and perivascular implantation of bioactive scaffolds engineered with human adventitial progenitor cells for stimulation of arteriogenesis in peripheral ischemia.

    PubMed

    Carrabba, M; De Maria, C; Oikawa, A; Reni, C; Rodriguez-Arabaolaza, I; Spencer, H; Slater, S; Avolio, E; Dang, Z; Spinetti, G; Madeddu, P; Vozzi, G

    2016-03-01

    Cell therapy represents a promising option for revascularization of ischemic tissues. However, injection of dispersed cells is not optimal to ensure precise homing into the recipient's vasculature. Implantation of cell-engineered scaffolds around the occluded artery may obviate these limitations. Here, we employed the synthetic polymer polycaprolactone for fabrication of 3D woodpile- or channel-shaped scaffolds by a computer-assisted writing system (pressure assisted micro-syringe square), followed by deposition of gelatin (GL) nanofibers by electro-spinning. Scaffolds were then cross-linked with natural (genipin, GP) or synthetic (3-glycidyloxy-propyl-trimethoxy-silane, GPTMS) agents to improve mechanical properties and durability in vivo. The composite scaffolds were next fixed by crown inserts in each well of a multi-well plate and seeded with adventitial progenitor cells (APCs, 3 cell lines in duplicate), which were isolated/expanded from human saphenous vein surgical leftovers. Cell density, alignment, proliferation and viability were assessed 1 week later. Data from in vitro assays showed channel-shaped/GPTMS-crosslinked scaffolds confer APCs with best alignment and survival/growth characteristics. Based on these results, channel-shaped/GPTMS-crosslinked scaffolds with or without APCs were implanted around the femoral artery of mice with unilateral limb ischemia. Perivascular implantation of scaffolds accelerated limb blood flow recovery, as assessed by laser Doppler or fluorescent microspheres, and increased arterial collaterals around the femoral artery and in limb muscles compared with non-implanted controls. Blood flow recovery and perivascular arteriogenesis were additionally incremented by APC-engineered scaffolds. In conclusion, perivascular application of human APC-engineered scaffolds may represent a novel option for targeted delivery of therapeutic cells in patients with critical limb ischemia. PMID:27011300

  11. Design, fabrication and perivascular implantation of bioactive scaffolds engineered with human adventitial progenitor cells for stimulation of arteriogenesis in peripheral ischemia.

    PubMed

    Carrabba, M; De Maria, C; Oikawa, A; Reni, C; Rodriguez-Arabaolaza, I; Spencer, H; Slater, S; Avolio, E; Dang, Z; Spinetti, G; Madeddu, P; Vozzi, G

    2016-03-01

    Cell therapy represents a promising option for revascularization of ischemic tissues. However, injection of dispersed cells is not optimal to ensure precise homing into the recipient's vasculature. Implantation of cell-engineered scaffolds around the occluded artery may obviate these limitations. Here, we employed the synthetic polymer polycaprolactone for fabrication of 3D woodpile- or channel-shaped scaffolds by a computer-assisted writing system (pressure assisted micro-syringe square), followed by deposition of gelatin (GL) nanofibers by electro-spinning. Scaffolds were then cross-linked with natural (genipin, GP) or synthetic (3-glycidyloxy-propyl-trimethoxy-silane, GPTMS) agents to improve mechanical properties and durability in vivo. The composite scaffolds were next fixed by crown inserts in each well of a multi-well plate and seeded with adventitial progenitor cells (APCs, 3 cell lines in duplicate), which were isolated/expanded from human saphenous vein surgical leftovers. Cell density, alignment, proliferation and viability were assessed 1 week later. Data from in vitro assays showed channel-shaped/GPTMS-crosslinked scaffolds confer APCs with best alignment and survival/growth characteristics. Based on these results, channel-shaped/GPTMS-crosslinked scaffolds with or without APCs were implanted around the femoral artery of mice with unilateral limb ischemia. Perivascular implantation of scaffolds accelerated limb blood flow recovery, as assessed by laser Doppler or fluorescent microspheres, and increased arterial collaterals around the femoral artery and in limb muscles compared with non-implanted controls. Blood flow recovery and perivascular arteriogenesis were additionally incremented by APC-engineered scaffolds. In conclusion, perivascular application of human APC-engineered scaffolds may represent a novel option for targeted delivery of therapeutic cells in patients with critical limb ischemia.

  12. Effects of Obesity on Perivascular Adipose Tissue Vasorelaxant Function: Nitric Oxide, Inflammation and Elevated Systemic Blood Pressure

    PubMed Central

    Aghamohammadzadeh, Reza; Unwin, Richard D.; Greenstein, Adam S.; Heagerty, Anthony M.

    2016-01-01

    Introduction Perivascular adipose tissue (PVAT) surrounds most vessels in the human body. Healthy PVAT has a vasorelaxant effect which is not observed in obesity. We assessed the contribution of nitric oxide (NO), inflammation and endothelium to obesity-induced PVAT damage. Methods Rats were fed a high-fat diet or normal chow. PVAT function was assessed using wire myography. Skeletonised and PVAT-intact mesenteric vessels were prepared with and without endothelium. Vessels were incubated with L-NNA or superoxide dismutase (SOD) and catalase. Gluteal fat biopsies were performed on 10 obese and 10 control individuals, and adipose tissue was assessed using proteomic analysis. Results In the animals, there were significant correlations between weight and blood pressure (BP; r = 0.5, p = 0.02), weight and PVAT function (r = 0.51, p = 0.02), and PVAT function and BP (r = 0.53, p = 0.01). PVAT-intact vessel segments from healthy animals constricted significantly less than segments from obese animals (p < 0.05). In a healthy state, there was preservation of the PVAT vasorelaxant function after endothelium removal (p < 0.05). In endothelium-denuded vessels, L-NNA attenuated the PVAT vasorelaxant function in control vessels (p < 0.0001). In obesity, incubation with SOD and catalase attenuated PVAT-intact vessel contractility in the presence and absence of endothelium (p < 0.001). In obese humans, SOD [Cu-Zn] (SOD1; fold change −2.4), peroxiredoxin-1 (fold change −2.15) and adiponectin (fold change −2.1) were present in lower abundances than in healthy controls. Conclusions Incubation with SOD and catalase restores PVAT vasorelaxant function in animal obesity. In the rodent model, obesity-induced PVAT damage is independent of endothelium and is in part due to reduced NO bioavailability within PVAT. Loss of PVAT function correlates with rising BP in our animal obesity model. In keeping with our hypothesis of inflammation-induced damage to PVAT function in obesity, there

  13. Proliferating cells in psoriatic dermis are comprised primarily of T cells, endothelial cells, and factor XIIIa+ perivascular dendritic cells

    SciTech Connect

    Morganroth, G.S.; Chan, L.S.; Weinstein, G.D.; Voorhees, J.J.; Cooper, K.D. )

    1991-03-01

    Determination of the cell types proliferating in the dermis of patients with psoriasis should identify those cells experiencing activation or responding to growth factors in the psoriatic dermal milieu. Toward that end, sections of formalin-fixed biopsies obtained from 3H-deoxyuridine (3H-dU)-injected skin of eight psoriatic patients were immunostained, followed by autoradiography. Proliferating dermal cells exhibit silver grains from tritium emissions. The identity of the proliferating cells could then be determined by simultaneous visualization with antibodies specific for various cell types. UCHL1+ (CD45RO+) T cells (recall antigen-reactive helper T-cell subset) constituted 36.6 +/- 3.1% (mean +/- SEM, n = 6) of the proliferating dermal cells in involved skin, whereas Leu 18+ (CD45RA+) T cells (recall antigen naive T-cell subsets) comprised only 8.7 +/- 1.5% (n = 6). The Factor XIIIa+ dermal perivascular dendritic cell subset (24.9 +/- 1.5% of proliferating dermal cells, n = 6) and Factor VIII+ endothelial cells represented the two other major proliferating populations in lesional psoriatic dermis. Differentiated tissue macrophages, identified by phase microscopy as melanophages or by immunostaining with antibodies to Leu M1 (CD15) or myeloid histiocyte antigen, comprised less than 5% of the proliferating population in either skin type. In addition to calculating the relative proportions of these cells to each other as percent, we also determined the density of cells, in cells/mm2 of tissue. The density of proliferating cells within these populations was increased in involved versus uninvolved skin: UCHL1+, 9.0 +/- 1.7 cells/mm2 versus 1.8 +/- 0.6 cells/mm2, p less than 0.01; Factor XIIIa+, 6.0 +/- 0.7 cells/mm2 versus 1.5 +/- 0.5 cells/mm2, p less than 0.01; Factor VIII+, 5.5 +/- 1.4 cells/mm2 versus 0.0 cells/mm2, p less than 0.05.

  14. Cordocytes-stem cells cooperation in the human brain with emphasis on pivotal role of cordocytes in perivascular areas of broken and thrombosed vessels.

    PubMed

    Pais, Viorel; Danaila, Leon; Pais, Emil

    2013-12-01

    This study is based on data analysis by light and transmission electron microscopy of the surgical cases in cerebral tumors, cerebrovascular malformations, thromboses in the carotid system, and other injuries such as perivascular hemorrhage. We examined cortical arteries and veins, perivascular areas with old hematic masses, vasculogenic foci, and broken large vessels. We identified, characterized, and compared both undifferentiated cells and well-differentiated cordocytes within periadventitial areas where these cells cooperate very well with precursor/stem cells to perform vital functions for cerebral vasculature with immediate effect on brain parenchyma. This useful cellular cooperation was observed by serial sections pointing out the main role of cordocytes during the entire process of collateral vessel formation after thrombosis and, respectively, in vascular wall repair after ruptures. This is the first cytohistopathological study which illustrates and explains some facets of cordocytes-stem cells cooperation around the vessels of human brain with emphasis on the fundamental role of cordocytes in response to vascular injuries. Our pioneering study will be completed for both basic science and modern medical care by further studies.

  15. Prostaglandin induced changes in the tone of porcine retinal arterioles in vitro involve other factors than calcium activity in perivascular cells.

    PubMed

    Kudryavtseva, Olga; Aalkjær, Christian; Bek, Toke

    2015-09-01

    The cellular basis for the regulation of retinal blood flow is unknown, but recently a new type of perivascular cell (PVC) with pericyte characteristics was identified in the retinal arterial vascular wall located immediately external to the vascular smooth muscle cells. A possible involvement of this cell type in the regulation of retinal vascular tone might be elucidated by studying differences in the response after the addition of compounds stimulating respectively relaxation and contraction. The effects of PGE2 and PGF2α on vascular tone and calcium activity in PVCs in porcine retinal arterioles were studied in a confocal myograph after the addition of the ryanodine receptor blocker ryanodine, the L-type Ca(2+) channel blocker nifedipine, the non-specific cation channel blocker LOE908, the sarcoplasmic reticulum Ca(2+)-ATPase (SERCA) blocker CPA, and the inositol triphosphate receptor (IP3R) and transient receptor potential (TRP) ion channel blocker 2-APB. The Ca(2+) channel blockers nifedipine and LOE908 induced significant relaxation of retinal arterioles. After the addition of both PGE2 and PGF2α calcium activity in the PVCs was significantly reduced by both the SERCA inhibitor CPA and the IP3R antagonist 2-APB, but the changes in calcium activity were unrelated to the changes in tone induced by PGE2 and PGF2α. Changes in the tone of porcine retinal arterioles in vitro induced by PGE2 and PGF2α involve other factors than calcium activity in the perivascular cells.

  16. Proliferation of Perivascular Macrophages Contributes to the Development of Encephalitic Lesions in HIV-Infected Humans and in SIV-Infected Macaques.

    PubMed

    Filipowicz, Adam R; McGary, Christopher M; Holder, Gerard E; Lindgren, Allison A; Johnson, Edward M; Sugimoto, Chie; Kuroda, Marcelo J; Kim, Woong-Ki

    2016-01-01

    The aim of the present study was to investigate if macrophage proliferation occurs in the brain during simian immunodeficiency virus (SIV) infection of adult macaques. We examined the expression of the Ki-67 proliferation marker in the brains of uninfected and SIV-infected macaques with or without encephalitis. Double-label immunohistochemistry using antibodies against the pan-macrophage marker CD68 and Ki-67 showed that there was a significant increase in CD68+Ki-67+ cells in macaques with SIV encephalitis (SIVE) compared to uninfected and SIV-infected animals without encephalitis, a trend that was also confirmed in brain samples from patients with HIV encephalitis. Multi-label immunofluorescence for CD163 and Ki-67 confirmed that the vast majority of Ki-67+ nuclei were localized to CD163+ macrophages in perivascular cuffs and lesions. The proliferative capacity of Ki-67+ perivascular macrophages (PVM) was confirmed by their nuclear incorporation of bromodeoxyuridine. Examining SIVE lesions, using double-label immunofluorescence with antibodies against SIV-Gag-p28 and Ki-67, showed that the population of Ki-67+ cells were productively infected and expanded proportionally with lesions. Altogether, this study shows that there are subpopulations of resident PVM that express Ki-67 and are SIV-infected, suggesting a mechanism of macrophage accumulation in the brain via PVM proliferation. PMID:27610547

  17. Proliferation of Perivascular Macrophages Contributes to the Development of Encephalitic Lesions in HIV-Infected Humans and in SIV-Infected Macaques

    PubMed Central

    Filipowicz, Adam R.; McGary, Christopher M.; Holder, Gerard E.; Lindgren, Allison A.; Johnson, Edward M.; Sugimoto, Chie; Kuroda, Marcelo J.; Kim, Woong-Ki

    2016-01-01

    The aim of the present study was to investigate if macrophage proliferation occurs in the brain during simian immunodeficiency virus (SIV) infection of adult macaques. We examined the expression of the Ki-67 proliferation marker in the brains of uninfected and SIV-infected macaques with or without encephalitis. Double-label immunohistochemistry using antibodies against the pan-macrophage marker CD68 and Ki-67 showed that there was a significant increase in CD68+Ki-67+ cells in macaques with SIV encephalitis (SIVE) compared to uninfected and SIV-infected animals without encephalitis, a trend that was also confirmed in brain samples from patients with HIV encephalitis. Multi-label immunofluorescence for CD163 and Ki-67 confirmed that the vast majority of Ki-67+ nuclei were localized to CD163+ macrophages in perivascular cuffs and lesions. The proliferative capacity of Ki-67+ perivascular macrophages (PVM) was confirmed by their nuclear incorporation of bromodeoxyuridine. Examining SIVE lesions, using double-label immunofluorescence with antibodies against SIV-Gag-p28 and Ki-67, showed that the population of Ki-67+ cells were productively infected and expanded proportionally with lesions. Altogether, this study shows that there are subpopulations of resident PVM that express Ki-67 and are SIV-infected, suggesting a mechanism of macrophage accumulation in the brain via PVM proliferation. PMID:27610547

  18. CLIPPERS: chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids. Review of an increasingly recognized entity within the spectrum of inflammatory central nervous system disorders

    PubMed Central

    Dudesek, A; Rimmele, F; Tesar, S; Kolbaske, S; Rommer, P S; Benecke, R; Zettl, U K

    2014-01-01

    Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is a recently defined inflammatory central nervous system (CNS) disorder, prominently involving the brainstem and in particular the pons. The condition features a combination of clinical symptoms essentially referable to brainstem pathology and a characteristic magnetic resonance imaging (MRI) appearance with punctate and curvilinear gadolinium enhancement ‘peppering’ the pons. The radiological distribution is focused in the pons and adjacent rhombencephalic structures such as the cerebellar peduncles, cerebellum, medulla and the midbrain. While the lesion burden with a perivascular pattern is typically most dense in these pontine and peripontine regions, enhancing lesions may additionally extend into the spinal cord and supratentorial structures such as the thalamus, basal ganglia, capsula interna, corpus callosum and the cerebral white matter. Another core feature is clinical and radiological responsiveness to glucocorticosteroid (GCS)-based immunosuppression. As withdrawal of GCS treatment results commonly in disease exacerbation, long-term immunosuppressive therapy appears to be mandatory for sustained improvement. Diagnosis of CLIPPERS is challenging, and requires careful exclusion of alternative diagnoses. A specific serum or cerebrospinal fluid (CSF) biomarker for the disorder is currently not known. Pathogenesis of CLIPPERS remains poorly understood, and the nosological position of CLIPPERS has still to be established. Whether CLIPPERS represents an independent, actual new disorder or a syndrome that includes aetiologically heterogeneous diseases and/or their prestages remains a debated and not finally clarified issue. Clinicians and radiologists should be aware of this condition and its differential diagnoses, given that CLIPPERS constitutes a treatable condition and that patients may benefit from an early introduction of GCS ensued by long

  19. Spironolactone Prevents Endothelial Nitric Oxide Synthase Uncoupling and Vascular Dysfunction Induced by β-Adrenergic Overstimulation: Role of Perivascular Adipose Tissue.

    PubMed

    Victorio, Jamaira A; Clerici, Stefano P; Palacios, Roberto; Alonso, María J; Vassallo, Dalton V; Jaffe, Iris Z; Rossoni, Luciana V; Davel, Ana P

    2016-09-01

    Sustained stimulation of β-adrenoceptors (β-ARs) and activation of renin-angiotensin-aldosterone system are common features of cardiovascular diseases with rising sympathetic activation, including essential hypertension, myocardial infarction, and heart failure. In this study, we investigated the role of AT1 receptor and mineralocorticoid receptor (MR) in the vascular alterations caused by β-AR overstimulation. β-AR overstimulation with associated cardiac hypertrophy and increased vasoconstrictor response to phenylephrine in aorta were modeled in rats by 7-day isoproterenol treatment. The increased vasoconstrictor response to phenylephrine in this model was blunted by the MR antagonist spironolactone, but not by the AT1 receptor antagonist losartan, despite the blunting of cardiac hypertrophy with both drugs. Spironolactone, but not losartan, restored NO bioavailability in association with lower endothelial nitric oxide synthase-derived superoxide production, increased endothelial nitric oxide synthase dimerization, and aortic HSP90 upregulation. MR genomic and nongenomic functions were activated in aortas from isoproterenol-treated rats. Isoproterenol did not modify plasma levels of MR ligands aldosterone and corticosterone but rather increased perivascular adipose tissue-derived corticosterone in association with increased expression of 11β-hydroxysteroid dehydrogenase type 1. The anticontractile effect of aortic perivascular adipose tissue was impaired by β-AR overstimulation and restored by MR blockade. These results suggest that activation of vascular MR signaling contributes to the vascular dysfunction induced by β-AR overstimulation associated with endothelial nitric oxide synthase uncoupling. These findings reveal an additional explanation for the protective effects of MR antagonists in cardiovascular disorders with sympathetic activation. PMID:27432866

  20. Involvement of perivascular nerves and transient receptor potential vanilloid 1 (TRPV1) in vascular responses to histamine in rat mesenteric resistance arteries.

    PubMed

    Jin, Honghua; Sun, Pengyuan; Takatori, Shingo; Koyama, Toshihiro; Zamami, Yoshito; Tangsucharit, Panot; Kitamura, Yoshihisa; Kawasaki, Hiromu

    2012-04-01

    A previous report showed that histamine in denuded mesenteric vascular beds produced a triphasic response; an initial small histamine H(2) receptor-mediated vasodilation, a transient histamine H(1) receptor-mediated vasoconstriction, and finally a long-lasting vasodilation. We further investigated the vascular effect of histamine in mesenteric preparations without an endothelium to clarify the possible involvement of perivascular nerves. Male Wistar rat mesenteric vascular beds without an endothelium were perfused with Krebs solution containing methoxamine to produce active tone and lafutidine to block histamine H(2) receptor-mediated vasodilation. Histamine (1-100μM) was perfused for 1min and perfusion pressure was measured with a pressure transducer. Histamine caused a biphasic vascular response; initial vasoconstriction followed vasodilation. Tetrodotoxin (a neurotoxin, 1μM) and procaine (a local anesthetic, 100μM) significantly inhibited the vasoconstriction and vasodilation. Ruthenium red (a transient receptor potential vanilloid 1 (TRPV1) antagonist, 1μM) also significantly inhibited both phases of the response. Pretreatment with capsaicin (a depletor of calcitonin gene-related peptide (CGRP)-containing nerves, 5μM) significantly inhibited the vasodilation without affecting the initial vasoconstriction. Both indomethacin (a cyclooxygenase inhibitor, 0.5μM) and seratrodast (a thromboxane A(2) receptor antagonist, 0.1μM) abolished the histamine-induced vasoconstriction and subsequent vasodilation. These results suggest that histamine-induced vasoconstriction and long-lasting vasodilation are mediated by activation of TRPV1 on capsaicin-sensitive and capsaicin-insensitive nerves. They also suggest that perivascular nerves and prostanoids, probably thromboxane A(2), are responsible for the vascular response to histamine.

  1. Human Umbilical Cord Perivascular Cells Exhibited Enhanced Migration Capacity towards Hepatocellular Carcinoma in Comparison with Bone Marrow Mesenchymal Stromal Cells: A Role for Autocrine Motility Factor Receptor

    PubMed Central

    Aquino, Jorge B.; Malvicini, Mariana; Bolontrade, Marcela; Podhajcer, Osvaldo; Garcia, Mariana G.; Mazzolini, Guillermo

    2014-01-01

    Hepatocellular carcinoma (HCC) is the third cause of cancer-related death worldwide. Unfortunately, the incidence and mortality associated with HCC are increasing. Therefore, new therapeutic strategies are urgently needed and the use of mesenchymal stromal cells (MSCs) as carrier of therapeutic genes is emerging as a promising option. Different sources of MSCs are being studied for cell therapy and bone marrow-derived cells are the most extensively explored; however, birth associated-tissues represent a very promising source. The aim of this work was to compare the in vitro and in vivo migration capacity between bone marrow MSCs (BM-MSCs) and human umbilical cord perivascular cells (HUCPVCs) towards HCC. We observed that HUCPVCs presented higher in vitro and in vivo migration towards factors released by HCC. The expression of autocrine motility factor (AMF) receptor, genes related with the availability of the receptor on the cell surface (caveolin-1 and -2) and metalloproteinase 3, induced by the receptor activation and important for cell migration, was increased in HUCPVCs. The chemotactic response towards recombinant AMF was increased in HUCPVCs compared to BM-MSCs, and its inhibition in the conditioned medium from HCC induced higher decrease in HUCPVC migration than in BM-MSC. Our results indicate that HUCPVCs could be a useful cellular source to deliver therapeutic genes to HCC. PMID:25147818

  2. Eruptive dermal clear cell desmo-plastic mesenchymal tumors with perivascular myoid differentiation in a young boy. A clinical, histopathologic, immunohistochemical and electron microscopy study of 17 lesions.

    PubMed

    Tomasini, Carlo; Metze, Dieter; Osella-Abate, Simona; Novelli, Mauro; Kutzner, Heinz

    2014-02-01

    Clear cell tumors of the skin are observed in a wide variety of benign and malignant conditions with different histogenesis, sharing the presence of cells with abundant clear cytoplasm. Herein, we report the clinicopathologic features of a healthy young patient affected by asymptomatic, eruptive and disseminated, benign clear cell dermal tumors since early infancy. Neither family history nor genetic testing and counseling provided further useful information. The lesions were mostly confined to the face and lower left extremity with pink teleangiectatic papules and small nodules. Over a 4-year period, a total of 16 different cutaneous lesions were biopsied and histopathologic and immunohistochemical studies carried out; an additional lesion was also removed for electron microscopy examination. Histopathology evidenced multiple perivascular growths of spindle to oval and round cells intermingled with clear/granular cells throughout the dermis, with prominent desmoplasia and numerous capillary-like vessels with focal hemangiopericytoma-like features. Immunohistochemical neoplastic cells were uniformly positive for h-caldesmon and focally smooth muscle α-actin and CD13 indicating myoid differentiation whereas the consistent diffuse cytoplasmic staining for lysosome antigen, such as CD68PG-M1 and NKI/C3 along with the ultrastructural findings supported the view of a lysosome-mediated apoptotic process. The differential diagnosis with other clear cell cutaneous neoplasms is discussed.

  3. Human umbilical cord perivascular cells exhibited enhanced migration capacity towards hepatocellular carcinoma in comparison with bone marrow mesenchymal stromal cells: a role for autocrine motility factor receptor.

    PubMed

    Bayo, Juan; Fiore, Esteban; Aquino, Jorge B; Malvicini, Mariana; Rizzo, Manglio; Peixoto, Estanislao; Alaniz, Laura; Piccioni, Flavia; Bolontrade, Marcela; Podhajcer, Osvaldo; Garcia, Mariana G; Mazzolini, Guillermo

    2014-01-01

    Hepatocellular carcinoma (HCC) is the third cause of cancer-related death worldwide. Unfortunately, the incidence and mortality associated with HCC are increasing. Therefore, new therapeutic strategies are urgently needed and the use of mesenchymal stromal cells (MSCs) as carrier of therapeutic genes is emerging as a promising option. Different sources of MSCs are being studied for cell therapy and bone marrow-derived cells are the most extensively explored; however, birth associated-tissues represent a very promising source. The aim of this work was to compare the in vitro and in vivo migration capacity between bone marrow MSCs (BM-MSCs) and human umbilical cord perivascular cells (HUCPVCs) towards HCC. We observed that HUCPVCs presented higher in vitro and in vivo migration towards factors released by HCC. The expression of autocrine motility factor (AMF) receptor, genes related with the availability of the receptor on the cell surface (caveolin-1 and -2) and metalloproteinase 3, induced by the receptor activation and important for cell migration, was increased in HUCPVCs. The chemotactic response towards recombinant AMF was increased in HUCPVCs compared to BM-MSCs, and its inhibition in the conditioned medium from HCC induced higher decrease in HUCPVC migration than in BM-MSC. Our results indicate that HUCPVCs could be a useful cellular source to deliver therapeutic genes to HCC.

  4. Time lapse in vivo microscopy reveals distinct dynamics of microglia-tumor environment interactions-a new role for the tumor perivascular space as highway for trafficking microglia.

    PubMed

    Bayerl, Simon Heinrich; Niesner, Raluca; Cseresnyes, Zoltan; Radbruch, Helena; Pohlan, Julian; Brandenburg, Susan; Czabanka, Marcus Alexander; Vajkoczy, Peter

    2016-07-01

    Microglial cells are critical for glioma growth and progression. However, only little is known about intratumoral microglial behavior and the dynamic interaction with the tumor. Currently the scarce understanding of microglial appearance in malignant gliomas merely originates from histological studies and in vitro investigations. In order to understand the pattern of microglia activity, motility and migration we designed an intravital study in an orthotopic murine glioma model using CX3CR1-eGFP(GFP/wt) mice. We analysed the dynamics of intratumoral microglia accumulation and activity, as well as microglia/tumor blood vessel interaction by epi-illumination and 2-photon laser scanning microscopy. We further investigated cellular and tissue function, including the enzyme activity of intratumoral and microglial NADPH oxidase measured by in vivo fluorescence lifetime imaging. We identified three morphological phenotypes of tumor-associated microglia cells with entirely different motility patterns. We found that NADPH oxidase activation is highly divergent in these microglia subtypes leading to different production levels of reactive oxygen species (ROS). We observed that microglia motility is highest within the perivascular niche, suggesting relevance of microglia/tumor blood vessel interactions. In line, reduction of tumor blood vessels by antivascular therapy confirmed the relevance of the tumor vessel compartment on microglia biology in brain tumors. In summary, we provide new insights into in vivo microglial behavior, regarding both morphology and function, in malignant gliomas. GLIA 2016;64:1210-1226.

  5. Unveiling the Differences of Secretome of Human Bone Marrow Mesenchymal Stem Cells, Adipose Tissue-Derived Stem Cells, and Human Umbilical Cord Perivascular Cells: A Proteomic Analysis.

    PubMed

    Pires, Ana O; Mendes-Pinheiro, Barbara; Teixeira, Fábio G; Anjo, Sandra I; Ribeiro-Samy, Silvina; Gomes, Eduardo D; Serra, Sofia C; Silva, Nuno A; Manadas, Bruno; Sousa, Nuno; Salgado, Antonio J

    2016-07-15

    The use of human mesenchymal stem cells (hMSCs) has emerged as a possible therapeutic strategy for CNS-related conditions. Research in the last decade strongly suggests that MSC-mediated benefits are closely related with their secretome. Studies published in recent years have shown that the secretome of hMSCs isolated from different tissue sources may present significant variation. With this in mind, the present work performed a comparative proteomic-based analysis through mass spectrometry on the secretome of hMSCs derived from bone marrow (BMSCs), adipose tissue (ASCs), and human umbilical cord perivascular cells (HUCPVCs). The results revealed that BMSCs, ASCs, and HUCPVCs differed in their secretion of neurotrophic, neurogenic, axon guidance, axon growth, and neurodifferentiative proteins, as well as proteins with neuroprotective actions against oxidative stress, apoptosis, and excitotoxicity, which have been shown to be involved in several CNS disorder/injury processes. Although important changes were observed within the secretome of the cell populations that were analyzed, all cell populations shared the capability of secreting important neuroregulatory molecules. The difference in their secretion pattern may indicate that their secretome is specific to a condition of the CNS. Nevertheless, the confirmation that the secretome of MSCs isolated from different tissue sources is rich in neuroregulatory molecules represents an important asset not only for the development of future neuroregenerative strategies but also for their use as a therapeutic option for human clinical trials. PMID:27226274

  6. Deposition of amyloid β in the walls of human leptomeningeal arteries in relation to perivascular drainage pathways in cerebral amyloid angiopathy☆

    PubMed Central

    Keable, Abby; Fenna, Kate; Yuen, Ho Ming; Johnston, David A.; Smyth, Neil R.; Smith, Colin; Salman, Rustam Al-Shahi; Samarasekera, Neshika; Nicoll, James A.R.; Attems, Johannes; Kalaria, Rajesh N.; Weller, Roy O.; Carare, Roxana O.

    2016-01-01

    Deposition of amyloid β (Aβ) in the walls of cerebral arteries as cerebral amyloid angiopathy (CAA) suggests an age-related failure of perivascular drainage of soluble Aβ from the brain. As CAA is associated with Alzheimer's disease and with intracerebral haemorrhage, the present study determines the unique sequence of changes that occur as Aβ accumulates in artery walls. Paraffin sections of post-mortem human occipital cortex were immunostained for collagen IV, fibronectin, nidogen 2, Aβ and smooth muscle actin and the immunostaining was analysed using Image J and confocal microscopy. Results showed that nidogen 2 (entactin) increases with age and decreases in CAA. Confocal microscopy revealed stages in the progression of CAA: Aβ initially deposits in basement membranes in the tunica media, replaces first the smooth muscle cells and then the connective tissue elements to leave artery walls completely or focally replaced by Aβ. The pattern of development of CAA in the human brain suggests expansion of Aβ from the basement membranes to progressively replace all tissue elements in the artery wall. Establishing this full picture of the development of CAA is pivotal in understanding the clinical presentation of CAA and for developing therapies to prevent accumulation of Aβ in artery walls. This article is part of a Special Issue entitled: Vascular Contributions to Cognitive Impairment and Dementia edited by M. Paul Murphy, Roderick A. Corriveau and Donna M. Wilcock. PMID:26327684

  7. "Malignant" uterine perivascular epithelioid cell tumor, pelvic lymph node lymphangioleiomyomatosis, and gynecological pecomatosis in a patient with tuberous sclerosis: a case report and review of the literature.

    PubMed

    Liang, Sharon X; Pearl, Michael; Liu, Jingxuan; Hwang, Sonia; Tornos, Carmen

    2008-01-01

    We report a case of uterine perivascular epithelioid cell tumor (PEComa) with malignant histological features in a 59-year-old woman with tuberous sclerosis (TBS). The patient also had extrapulmonary lymphangioleiomyomatosis involving pelvic lymph nodes, myometrium, cervix, and ovary ("pecomatosis"). The uterine tumor measured 2.6 cm and had marked nuclear pleomorphism, necrosis, and 2 mitoses per 50 high-powered field, with an occasional atypical mitosis and infiltrative borders. The nonneoplastic myometrium, the cervical wall, and the hilum of the ovary had multiple clusters of bland-looking epithelioid clear cells that ranged from 1 to 5 mm (pecomatosis). The uterine tumor cells were positive for HMB-45 (90%), Melan-A (70%), smooth muscle actin (50%), and estrogen receptor (30%). Of the 16 pelvic lymph nodes excised, 3 were involved with lymphangioleiomyomatosis that was positive for HMB-45 and estrogen receptor. This is only the second reported PEComa associated with pecomatosis and the fourth PEComa described in a patient with TBS. The clinical significance of pecomatosis is still uncertain but seems to be seen only in patients with TBS.

  8. Transmission and scanning electron microscopy study of the characteristics and morphology of pericytes and novel desmin-immunopositive perivascular cells before and after castration in rat anterior pituitary gland.

    PubMed

    Jindatip, Depicha; Fujiwara, Ken; Kouki, Tom; Yashiro, Takashi

    2012-09-01

    Pericytes are perivascular cells associated with microcirculation. Typically, they are localized close to the capillary wall, underneath the basement membrane, and have sparse cytoplasm and poorly developed cell organelles. However, the specific properties of pericytes vary by organ and the conditions within organs. We recently demonstrated that pericytes in rat anterior pituitary gland produce type I and III collagens. The present study attempted to determine the morphological characteristics of these pituitary pericytes. Castrated rats were used as a model of hormonal and vascular changes in the gland. Pericytes, as determined by desmin immunohistochemistry, were more numerous and stained more intensely in castrated rats. Transmission electron microscopy revealed that pituitary pericytes displayed the typical characteristics of pericytes. In pituitary sections from castrated rats, the Golgi apparatus of pericytes was well developed and the rough endoplasmic reticulum was elongated. Additionally, scanning electron microscopy revealed four pericyte shapes: oval, elongate, triangular, and multiangular. As compared with normal rats, the proportion of oval pericytes was lower, and the proportions of the other three shapes were higher, in castrated rats. These results suggest that pericytes change their fine structure and cell shape in response to hormonal and vascular changes in the anterior pituitary gland. In addition, a novel type of perivascular cell was found by desmin immunoelectron microscopy. The morphological properties of these cells were dissimilar to those of pericytes. The cells were localized in the perivascular space, had no basement membrane, and contained dilated rough endoplasmic reticulum. This new cell type will require further study of its origin and characteristics.

  9. Alpha-syntrophin deletion removes the perivascular but not endothelial pool of aquaporin-4 at the blood-brain barrier and delays the development of brain edema in an experimental model of acute hyponatremia.

    PubMed

    Amiry-Moghaddam, Mahmood; Xue, Rong; Haug, Finn-Mogens; Neely, John D; Bhardwaj, Anish; Agre, Peter; Adams, Marvin E; Froehner, Stanley C; Mori, Susumu; Ottersen, Ole P

    2004-03-01

    The formation of brain edema, commonly occurring as a potentially lethal complication of acute hyponatremia, is delayed following knockout of the water channel aquaporin-4 (AQP4). Here we show by high-resolution immunogold analysis of the blood-brain-barrier that AQP4 is expressed in brain endothelial cells as well as in the perivascular membranes of astrocyte endfeet. A selective removal of perivascular AQP4 by alpha-syntrophin deletion delays the buildup of brain edema (assessed by Diffusion-weighted MRI) following water intoxication, despite the presence of a normal complement of endothelial AQP4. This indicates that the perivascular membrane domain, which is peripheral to the endothelial blood-brain barrier, may control the rate of osmotically driven water entry. This study is also the first to demonstrate that the time course of edema development differs among brain regions, probably reflecting differences in aquaporin-4 distribution. The resolution of the molecular basis and subcellular site of osmotically driven brain water uptake should help design new therapies for acute brain edema.

  10. Dahl SS rats demonstrate enhanced aortic perivascular adipose tissue-mediated buffering of vasoconstriction through activation of NOS in the endothelium.

    PubMed

    Spradley, Frank T; Ho, Dao H; Pollock, Jennifer S

    2016-02-01

    Perivascular adipose tissue (PVAT) mediates buffering of vasoconstriction through activation of endothelium-derived factors. We hypothesized that the PVAT of Dahl salt-sensitive (Dahl SS) rats has reduced ability to buffer vasoconstriction. Vascular reactivity experiments were performed on aortic rings with PVAT intact (+PVAT) or removed (-PVAT), and endothelium intact (+ENDO) or removed (-ENDO) from Dahl SS rats and control SS.13(BN) rats (Dahl SS rats that have had chromosome 13 completely replaced with that of the Brown Norway rat, rendering this strain insensitive to high-salt or high-fat diet-induced hypertension). Endothelial dysfunction, assessed by ACh-mediated vasorelaxation, was confirmed in aortic rings of Dahl SS rats. The +PVAT+ENDO aortic rings had indistinguishable phenylephrine-induced vasoconstriction between genotypes. In both strains, removal of PVAT significantly enhanced vasoconstriction. Dahl SS rat -PVAT+ENDO aortic rings displayed exaggerated vasoconstriction to phenylephrine vs. SS.13(BN) rats, indicating that PVAT-mediated buffering of vasoconstriction was greater in Dahl SS rats. Removal of both the ENDO and PVAT restored vasoconstriction in both strains. The nitric oxide synthase (NOS) inhibitor, N(ω)-nitro-L-arginine methyl ester (L-NAME), produced a similar effect as that seen with -ENDO. These data indicate that the function of the PVAT to activate endothelium-derived NOS is enhanced in Dahl SS compared with SS.13(BN) rats and, most likely, occurs through a pathway that is distinct from ACh-mediated activation of NOS. PVAT weight and total PVAT leptin levels were greater in Dahl SS rats. Leptin induced a significantly decreased vasoconstriction in -PVAT+ENDO aortic rings from Dahl SS rats, but not SS.13(BN) rats. In contrast to our initial hypothesis, PVAT in Dahl SS rats buffers vasoconstriction by activating endothelial NOS via mechanisms that may include the involvement of leptin. Thus, the PVAT serves a vasoprotective role in

  11. Dahl SS rats demonstrate enhanced aortic perivascular adipose tissue-mediated buffering of vasoconstriction through activation of NOS in the endothelium.

    PubMed

    Spradley, Frank T; Ho, Dao H; Pollock, Jennifer S

    2016-02-01

    Perivascular adipose tissue (PVAT) mediates buffering of vasoconstriction through activation of endothelium-derived factors. We hypothesized that the PVAT of Dahl salt-sensitive (Dahl SS) rats has reduced ability to buffer vasoconstriction. Vascular reactivity experiments were performed on aortic rings with PVAT intact (+PVAT) or removed (-PVAT), and endothelium intact (+ENDO) or removed (-ENDO) from Dahl SS rats and control SS.13(BN) rats (Dahl SS rats that have had chromosome 13 completely replaced with that of the Brown Norway rat, rendering this strain insensitive to high-salt or high-fat diet-induced hypertension). Endothelial dysfunction, assessed by ACh-mediated vasorelaxation, was confirmed in aortic rings of Dahl SS rats. The +PVAT+ENDO aortic rings had indistinguishable phenylephrine-induced vasoconstriction between genotypes. In both strains, removal of PVAT significantly enhanced vasoconstriction. Dahl SS rat -PVAT+ENDO aortic rings displayed exaggerated vasoconstriction to phenylephrine vs. SS.13(BN) rats, indicating that PVAT-mediated buffering of vasoconstriction was greater in Dahl SS rats. Removal of both the ENDO and PVAT restored vasoconstriction in both strains. The nitric oxide synthase (NOS) inhibitor, N(ω)-nitro-L-arginine methyl ester (L-NAME), produced a similar effect as that seen with -ENDO. These data indicate that the function of the PVAT to activate endothelium-derived NOS is enhanced in Dahl SS compared with SS.13(BN) rats and, most likely, occurs through a pathway that is distinct from ACh-mediated activation of NOS. PVAT weight and total PVAT leptin levels were greater in Dahl SS rats. Leptin induced a significantly decreased vasoconstriction in -PVAT+ENDO aortic rings from Dahl SS rats, but not SS.13(BN) rats. In contrast to our initial hypothesis, PVAT in Dahl SS rats buffers vasoconstriction by activating endothelial NOS via mechanisms that may include the involvement of leptin. Thus, the PVAT serves a vasoprotective role in

  12. Perivascular tissue inhibits rho-kinase-dependent smooth muscle Ca(2+) sensitivity and endothelium-dependent H2 S signalling in rat coronary arteries.

    PubMed

    Aalbaek, Filip; Bonde, Lisbeth; Kim, Sukhan; Boedtkjer, Ebbe

    2015-11-01

    Interactions between perivascular tissue (PVT) and the vascular wall modify artery tone and contribute to local blood flow regulation. Using isometric myography, fluorescence microscopy, membrane potential recordings and phosphospecific immunoblotting, we investigated the cellular mechanisms by which PVT affects constriction and relaxation of rat coronary septal arteries. PVT inhibited vasoconstriction to thromboxane, serotonin and α1 -adrenergic stimulation but not to depolarization with elevated extracellular [K(+) ]. When PVT was wrapped around isolated arteries or placed at the bottom of the myograph chamber, a smaller yet significant inhibition of vasoconstriction was observed. Resting membrane potential, depolarization to serotonin or thromboxane stimulation, and resting and serotonin-stimulated vascular smooth muscle [Ca(2+) ]-levels were unaffected by PVT. Serotonin-induced vasoconstriction was almost abolished by rho-kinase inhibitor Y-27632 and modestly reduced by protein kinase C inhibitor bisindolylmaleimide X. PVT reduced phosphorylation of myosin phosphatase targeting subunit (MYPT) at Thr850 by ∼40% in serotonin-stimulated arteries but had no effect on MYPT-phosphorylation in arteries depolarized with elevated extracellular [K(+) ]. The net anti-contractile effect of PVT was accentuated after endothelial denudation. PVT also impaired vasorelaxation and endothelial Ca(2+) responses to cholinergic stimulation. Methacholine-induced vasorelaxation was mediated by NO and H2 S, and particularly the H2 S-dependent (dl-propargylglycine- and XE991-sensitive) component was attenuated by PVT. Vasorelaxation to NO- and H2 S-donors was maintained in arteries with PVT. In conclusion, cardiomyocyte-rich PVT surrounding coronary arteries releases diffusible factors that reduce rho-kinase-dependent smooth muscle Ca(2+) sensitivity and endothelial Ca(2+) responses. These mechanisms inhibit agonist-induced vasoconstriction and endothelium-dependent vasorelaxation

  13. Developmental aspects of the intracerebral microvasculature and perivascular spaces: insights into brain response to late-life diseases.

    PubMed

    Marín-Padilla, Miguel; Knopman, David S

    2011-12-01

    The development of the microvasculature of the human cerebral cortex offers insight into the response of the cerebral cortex to later-life brain injury. We describe the 3 basic and distinct components of the developmental anatomy of the cerebral cortical microvascular system. The first compartment is meningeal and, therefore, extracerebral. In addition to the major venous sinuses, arachnoidal arteries, and veins, the pial anastomotic capillary plexus that covers the surface of the developing and adult cerebral cortex represents the source of thepenetrating vessels that become the second component, the intracerebral extrinsic microvascular compartment. During embryogenesis, sprouting vascular elements from pial capillaries pierce the brain's external glial limiting membrane and penetrate the cortex. These vessels, which eventually differentiate into arterioles and venules, are separated from the cortical tissue by the extravascular Virchow-Robin compartment (V-RC) formed between the internal vascular and the external glial basal laminae. The V-RC remains open to the meningeal interstitial spaces and outside the blood-brain barrier (BBB) and acts asa prelymphatic drainage system for removal of substances that cannot be transported into the blood or catabolized intracellularly. The third element is the dense intracerebralintrinsic microvascular compartment. Intracerebral capillary vessels sprout from the perforating vessels, penetrate through the Virchow-Robin glial membrane, and enter the neuropil. Intracerebral capillaries lack smooth muscle and a V-RC and consist only of endothelial cells separated from the intracerebral space by a basal lamina. Their role as the physiological BBB is the exchange of oxygen, glucose, and small molecules. This developmental perspective highlights 3 principles: (a) the V-RC is intimately related to the cortical penetrating arterioles and venules and represents an inefficient protolymphatic system that lacks the anatomic and

  14. The Role of DPO-1 and XE991-Sensitive Potassium Channels in Perivascular Adipose Tissue-Mediated Regulation of Vascular Tone

    PubMed Central

    Tsvetkov, Dmitry; Tano, Jean-Yves; Kassmann, Mario; Wang, Ning; Schubert, Rudolf; Gollasch, Maik

    2016-01-01

    The anti-contractile effect of perivascular adipose tissue (PVAT) is an important mechanism in the modulation of vascular tone in peripheral arteries. Recent evidence has implicated the XE991-sensitive voltage-gated KV (KCNQ) channels in the regulation of arterial tone by PVAT. However, until now the in vivo pharmacology of the involved vascular KV channels with regard to XE991 remains undetermined, since XE991 effects may involve Ca2+ activated BKCa channels and/or voltage-dependent KV1.5 channels sensitive to diphenyl phosphine oxide-1 (DPO-1). In this study, we tested whether KV1.5 channels are involved in the control of mesenteric arterial tone and its regulation by PVAT. Our study was also aimed at extending our current knowledge on the in situ vascular pharmacology of DPO-1 and XE991 regarding KV1.5 and BKCa channels, in helping to identify the nature of K+ channels that could contribute to PVAT-mediated relaxation. XE991 at 30 μM reduced the anti-contractile response of PVAT, but had no effects on vasocontraction induced by phenylephrine (PE) in the absence of PVAT. Similar effects were observed for XE991 at 0.3 μM, which is known to almost completely inhibit mesenteric artery VSMC KV currents. 30 μM XE991 did not affect BKCa currents in VSMCs. Kcna5−/− arteries and wild-type arteries incubated with 1 μM DPO-1 showed normal vasocontractions in response to PE in the presence and absence of PVAT. KV current density and inhibition by 30 μM XE991 were normal in mesenteric artery VSMCs isolated from Kcna5−/− mice. We conclude that KV channels are involved in the control of arterial vascular tone by PVAT. These channels are present in VSMCs and very potently inhibited by the KCNQ channel blocker XE991. BKCa channels and/or DPO-1 sensitive KV1.5 channels in VSMCs are not the downstream mediators of the XE991 effects on PVAT-dependent arterial vasorelaxation. Further studies will need to be undertaken to examine the role of other KV channels in the

  15. The Role of DPO-1 and XE991-Sensitive Potassium Channels in Perivascular Adipose Tissue-Mediated Regulation of Vascular Tone.

    PubMed

    Tsvetkov, Dmitry; Tano, Jean-Yves; Kassmann, Mario; Wang, Ning; Schubert, Rudolf; Gollasch, Maik

    2016-01-01

    The anti-contractile effect of perivascular adipose tissue (PVAT) is an important mechanism in the modulation of vascular tone in peripheral arteries. Recent evidence has implicated the XE991-sensitive voltage-gated KV (KCNQ) channels in the regulation of arterial tone by PVAT. However, until now the in vivo pharmacology of the involved vascular KV channels with regard to XE991 remains undetermined, since XE991 effects may involve Ca(2+) activated BKCa channels and/or voltage-dependent KV1.5 channels sensitive to diphenyl phosphine oxide-1 (DPO-1). In this study, we tested whether KV1.5 channels are involved in the control of mesenteric arterial tone and its regulation by PVAT. Our study was also aimed at extending our current knowledge on the in situ vascular pharmacology of DPO-1 and XE991 regarding KV1.5 and BKCa channels, in helping to identify the nature of K(+) channels that could contribute to PVAT-mediated relaxation. XE991 at 30 μM reduced the anti-contractile response of PVAT, but had no effects on vasocontraction induced by phenylephrine (PE) in the absence of PVAT. Similar effects were observed for XE991 at 0.3 μM, which is known to almost completely inhibit mesenteric artery VSMC KV currents. 30 μM XE991 did not affect BKCa currents in VSMCs. Kcna5 (-/-) arteries and wild-type arteries incubated with 1 μM DPO-1 showed normal vasocontractions in response to PE in the presence and absence of PVAT. KV current density and inhibition by 30 μM XE991 were normal in mesenteric artery VSMCs isolated from Kcna5 (-/-) mice. We conclude that KV channels are involved in the control of arterial vascular tone by PVAT. These channels are present in VSMCs and very potently inhibited by the KCNQ channel blocker XE991. BKCa channels and/or DPO-1 sensitive KV1.5 channels in VSMCs are not the downstream mediators of the XE991 effects on PVAT-dependent arterial vasorelaxation. Further studies will need to be undertaken to examine the role of other KV channels in the

  16. Perivascular adipose tissue-derived leptin promotes vascular smooth muscle cell phenotypic switching via p38 mitogen-activated protein kinase in metabolic syndrome rats.

    PubMed

    Li, Hao; Wang, Ya-Ping; Zhang, Li-Na; Tian, Gang

    2014-04-01

    Perivascular adipose tissue (PVAT)-derived leptin is a detrimental adipocytokine and plays a critical role in the development of cardiovascular diseases in metabolic syndrome (MetS). During vascular remodeling, vascular smooth muscle cells (VSMCs) undergo phenotypic switching into a synthetic phenotype characterized by decreased expression of differentiation markers (smooth muscle myosin heavy chain, α-smooth muscle actin, and calponin) and increased proliferation. We aimed to determine whether PVAT-derived leptin influences VSMC phenotypic switching and to explore the underlying mechanisms in MetS rats. In vivo, 32 Wistar rats were divided into two groups that received either a normal diet (control rat) or a high-fat diet (MetS rats). After 16 weeks, rat aortas were stained using hematoxylin-eosin and imaged. VSMC differentiation markers and proliferating cell nuclear antigen (PCNA), PVAT-derived leptin, aortic leptin receptor (ObR), and p38 mitogen-activated protein kinase (MAPK) expression were detected. In vitro, aortic VSMCs were incubated with MetS rat PVAT conditioned medium (PVAT-CM) to mimic in vivo conditions and were pretreated with a p38 MAPK inhibitor (SB 203580) or leptin antagonist. Differentiation marker expression, including PCNA and p38 MAPK, was detected. MetS rats exhibited pronounced insulin resistance, hyperglycemia, hyperlipidemia, hypertension, obesity, and an associated increase in PVAT weight. VSMCs underwent phenotypic switching in MetS rat aorta and contributed to vascular remodeling. PVAT-derived leptin expression was higher in MetS rats than in control rats (P < 0.01). ObRa expression and p38 MAPK phosphorylation were upregulated in MetS rat aorta. In vitro, VSMCs incubated with MetS rat PVAT-CM underwent phenotypic switching, associated with increased p38 MAPK phosphorylation. This VSMC phenotypic switching was inhibited by pretreatment with SB 203580 or a leptin antagonist. These results suggest that in MetS rats, PVAT

  17. Permission Forms

    ERIC Educational Resources Information Center

    Zirkel, Perry A.

    2005-01-01

    The prevailing practice in public schools is to routinely require permission or release forms for field trips and other activities that pose potential for liability. The legal status of such forms varies, but they are generally considered to be neither rock-solid protection nor legally valueless in terms of immunity. The following case and the…

  18. Good form.

    PubMed

    Sorrel, Amy Lynn

    2015-03-01

    New standardized prior authorization forms for health care services and prescription drugs released by the Texas Department of Insurance promise to alleviate administrative busy work and its related costs.

  19. A rosette-forming glioneuronal tumor of the fourth ventricle: infratentorial form of dysembryoplastic neuroepithelial tumor?

    PubMed

    Komori, Takashi; Scheithauer, Bernd W; Hirose, Takanori

    2002-05-01

    Eleven cases of a distinctive tumor of the posterior fossa are described. The patients (age range 12-59 years) presented with headache and/or ataxia. Neuroimaging revealed a relatively discrete, focally enhancing mass(es) primarily involving the aqueduct, fourth ventricle, and cerebellar vermis. Hydrocephalus was present in seven cases, and two lesions were multicentric. In two cases a significant increase in tumor size was documented. Gross total or subtotal resections were achieved in 10 cases. One patient underwent biopsy alone and another received postoperative irradiation. Histologically, two components were identified in all cases. One consisted of neurocytes forming neurocytic and/or perivascular pseudorosettes in a fibrillary, partly microcystic matrix. The second, astrocytic component resembled pilocytic astrocytoma in 10 cases and consisted of fibrillated spindle cells with oval nuclei associated with occasional Rosenthal fibers, granular bodies, glomeruloid capillaries, and microcalcifications. Regionally, this component was more diffuse and patternless, consisting of sheets of round to oval, oligodendrocyte-like cells. Rare ganglion cells were seen in four cases. The rosettes were consistently synaptophysin and MAP-2 immunoreactive, whereas the spindle cells were positive for S-100 protein and glial fibrillary acidic protein. Overall, atypia was minimal; no mitoses were found, and Ki67 labeling indices were low. Ultrastructurally, the neurocytic cells featured processes containing microtubules and occasional dense core granules. Mature synapses were found in one of the four cases studied. Although the histologic features of this unique tumor superficially resemble those of dysembryoplastic neuroepithelial tumor, rosette formation by neuronal cells, the frequent presence of a pilocytic astrocytoma component, and the growing nature of the lesion argue against that diagnosis, as does occasional multifocality.

  20. Densified waste form and method for forming

    DOEpatents

    Garino, Terry J.; Nenoff, Tina M.; Sava Gallis, Dorina Florentina

    2016-05-17

    Materials and methods of making densified waste forms for temperature sensitive waste material, such as nuclear waste, formed with low temperature processing using metallic powder that forms the matrix that encapsulates the temperature sensitive waste material. The densified waste form includes a temperature sensitive waste material in a physically densified matrix, the matrix is a compacted metallic powder. The method for forming the densified waste form includes mixing a metallic powder and a temperature sensitive waste material to form a waste form precursor. The waste form precursor is compacted with sufficient pressure to densify the waste precursor and encapsulate the temperature sensitive waste material in a physically densified matrix.

  1. Densified waste form and method for forming

    SciTech Connect

    Garino, Terry J.; Nenoff, Tina M.; Sava Gallis, Dorina Florentina

    2015-08-25

    Materials and methods of making densified waste forms for temperature sensitive waste material, such as nuclear waste, formed with low temperature processing using metallic powder that forms the matrix that encapsulates the temperature sensitive waste material. The densified waste form includes a temperature sensitive waste material in a physically densified matrix, the matrix is a compacted metallic powder. The method for forming the densified waste form includes mixing a metallic powder and a temperature sensitive waste material to form a waste form precursor. The waste form precursor is compacted with sufficient pressure to densify the waste precursor and encapsulate the temperature sensitive waste material in a physically densified matrix.

  2. The perivascular niche regulates breast tumor dormancy

    PubMed Central

    Peinado, Héctor; Mori, Hidetoshi; Matei, Irina R.; Evason, Kimberley J.; Brazier, Hélène; Almeida, Dena; Koller, Antonius; Hajjar, Katherine A.; Stainier, Didier Y.R.; Chen, Emily I.; Lyden, David

    2013-01-01

    In a significant fraction of breast cancer patients, distant metastases emerge after years or even decades of latency. How disseminated tumor cells (DTCs) are kept dormant, and what ‘wakes them up’, are fundamental problems in tumor biology. To address these questions, we utilized metastasis assays in mice to show that dormant DTCs reside upon microvasculature of lung, bone marrow and brain. We then engineered organotypic microvascular niches to determine whether endothelial cells directly influence breast cancer cell (BCC) growth. These models demonstrated that endothelial-derived thrombospondin-1 induces sustained BCC quiescence. This suppressive cue was lost in sprouting neovasculature; time-lapse analysis showed that sprouting vessels not only permit, but accelerate BCC outgrowth. We confirmed this surprising result in dormancy models and in zebrafish, and identified active TGF-β1 and periostin as tumor-promoting, endothelial tip cell-derived factors. Our work reveals that stable microvasculature constitutes a ‘dormant niche,’ whereas sprouting neovasculature sparks micrometastatic outgrowth. PMID:23728425

  3. Involvement of IGF-1 and MEOX2 in PI3K/Akt1/2 and ERK1/2 pathways mediated proliferation and differentiation of perivascular adipocytes

    SciTech Connect

    Liu, Ping; Kong, Feng; Wang, Jue; Lu, Qinghua; Xu, Haijia; Qi, Tonggang; Meng, Juan

    2015-02-01

    Perivascular adipocyte (PVAC) proliferation and differentiation were closely involved in cardiovascular disease. We aimed to investigate whether phosphatidylinositol 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) signaling pathways enhance PVAC functions activated by insulin-like growth factor 1(IGF-1) and suppressed by mesenchyme homeobox 2 (MEOX2). In this study, PVACs from primary culture were cultured and induced to differentiate. Cell viability assays demonstrated that IGF-1 promoted PVAC proliferation and differentiation. However MEOX2 counteracted these IGF-1-mediated actions. Flow Cytometry revealed that IGF-1 increased S phase cells and decreased apoptosis; however, MEOX2 decreased S phase cells, increased G0–G1 phase cells, and promoted apoptosis. During PVAC proliferation and differentiation, IGF-1 activated PI3K/Akt1/2 and ERK1/2 signaling pathways, upregulated the expression of these signaling proteins and FAS, and increased PVAC lipid content. In contrast, MEOX2 constrained the phosphorylation of ERK1/2 and Akt1/2 protein, down-regulated these signaling molecules and FAS, and decreased PVAC lipid content. Instead, MEOX2 knockdown enhanced the ERK1/2 and Akt1/2 phosphorylation, augmented the expression of these signaling molecules and FAS, and increased PVAC lipid content. Our findings suggested that PI3K/Akt1/2 and ERK1/2 activation mediated by IGF-1 is essential for PVAC proliferation and differentiation, and MEOX2 is a promising therapeutic gene to intervene in the signaling pathways and inhibit PVAC functions. - Highlights: • IGF-1 activated PI3K/Akt2 and ERK1/2 pathways to mediate PVAC proliferation and differentiation. • The expression of ERK1, ERK 2, PI3K, Akt1 and Akt2 showed different change trends between PVAC proliferation and differentiation. • MEOX2 effectively expressed in PVAC, increased early and late cellular apoptosis, and inhibited its proliferation. • MEOX2 depressed PVAC differentiation and FAS expression

  4. PSF/SFPQ is a very common gene fusion partner in TFE3 rearrangement-associated perivascular epithelioid cell tumors (PEComas) and melanotic Xp11 translocation renal cancers: clinicopathologic, immunohistochemical, and molecular characteristics suggesting classification as a distinct entity.

    PubMed

    Rao, Qiu; Shen, Qin; Xia, Qiu-yuan; Wang, Zi-yu; Liu, Biao; Shi, Shan-shan; Shi, Qun-li; Yin, Hong-lin; Wu, Bo; Ye, Sheng-bing; Li, Li; Chen, Jie-Yu; Pan, Min-hong; Li, Qing; Li, Rui; Wang, Xuan; Zhang, Ru-song; Yu, Bo; Ma, Heng-hui; Lu, Zhen-feng; Zhou, Xiao-jun

    2015-09-01

    An increasing number of TFE3 rearrangement-associated tumors, such as TFE3 rearrangement-associated perivascular epithelioid cell tumors (PEComas), melanotic Xp11 translocation renal cancers, and melanotic Xp11 neoplasms, have recently been reported. We examined 12 such cases, including 5 TFE3 rearrangement-associated PEComas located in the pancreas, cervix, or pelvis and 7 melanotic Xp11 translocation renal cancers, using clinicopathologic, immunohistochemical, and molecular analyses. All the tumors shared a similar morphology, including a purely nested or sheet-like architecture separated by a delicate vascular network, purely epithelioid cells displaying a clear or granular eosinophilic cytoplasm, a lack of papillary structures and spindle cell or fat components, uniform round or oval nuclei containing small visible nucleoli, and, in most cases (11/12), melanin pigmentation. The levels of mitotic activity and necrosis varied. All 12 cases displayed moderately (2+) or strongly (3+) positive immunoreactivity for TFE3 and cathepsin K. One case labeled focally for HMB45 and Melan-A, whereas the others typically labeled moderately (2+) or strongly (3+) for 1 of these markers. None of the cases were immunoreactive for smooth muscle actin, desmin, CKpan, S100, or PAX8. PSF-TFE3 fusion genes were confirmed by reverse transcription polymerase chain reaction in cases (7/7) in which a novel PSF-TFE3 fusion point was identified. All of the cases displayed TFE3 rearrangement associated with Xp11 translocation. Furthermore, we developed a PSF-TFE3 fusion fluorescence in situ hybridization assay for the detection of the PSF-TFE3 fusion gene and detected it in all 12 cases. Clinical follow-up data were available for 7 patients. Three patients died, and 2 patients (cases 1 and 3) remained alive with no evidence of disease after initial resection. Case 2 experienced recurrence and remained alive with disease. Case 5, a recent case, remained alive with extensive abdominal cavity

  5. Bacteria form tellurium nanocrystals

    USGS Publications Warehouse

    Oremland, R.S.

    2007-01-01

    A team of researchers have found two bacterial species that produce tellurium oxyanions as respiratory electron acceptors for growth, leaving elemental tellurium in the form of nanoparticles. The crystals from the two organisms exhibit distinctively different structures. Bacillus selenitireducens initially forms nanorods that cluster together to form rosettes. Sulfurospirillum barnesii forms irregularly-shaped nanospheres that coalesce into larger composite aggregates.

  6. Handbook of Poetic Forms.

    ERIC Educational Resources Information Center

    Padgett, Ron, Ed.

    Intended for secondary teachers and student writers but useful for anyone interested in poetic forms, this book defines 74 basic poetic forms, summarizes their histories, quotes examples from noted poets, and offers professional tricks of the trade on how to use each form. The book covers the following poetic forms: abstract poem, acrostic,…

  7. Molecular Profiling of a Rare Rosette-Forming Glioneuronal Tumor Arising in the Spinal Cord

    PubMed Central

    Bidinotto, Lucas Tadeu; Scapulatempo-Neto, Cristovam; Mackay, Alan; de Almeida, Gisele Caravina; Berardinelli, Gustavo Noriz; Torrieri, Raul; Clara, Carlos Afonso; Feltrin, Leonir Terezinha; Viana-Pereira, Marta; Varella-Garcia, Marileila; Jones, Chris; Reis, Rui Manuel

    2015-01-01

    Rosette-forming glioneuronal tumor (RGNT) of the IV ventricle is a rare and recently recognized brain tumor entity. It is histologically composed by two distinct features: a glial component, resembling pilocytic astrocytoma, and a component forming neurocytic rosettes and/or perivascular rosettes. Herein, we describe a 33-year-old man with RGNT arising in the spinal cord. Following an immunohistochemistry validation, we further performed an extensive genomic analysis, using array-CGH (aCGH), whole exome and cancer-related hotspot sequencing, in order to better understand its underlying biology. We observed the loss of 1p and gain of 1q, as well as gain of the whole chromosomes 7, 9 and 16. Local amplifications in 9q34.2 and 19p13.3 (encompassing the gene SBNO2) were identified. Moreover, we observed focal gains/losses in several chromosomes. Additionally, on chromosome 7, we identified the presence of the KIAA1549:BRAF gene fusion, which was further validated by RT-PCR and FISH. Across all mutational analyses, we detected and validated the somatic mutations of the genes MLL2, CNNM3, PCDHGC4 and SCN1A. Our comprehensive molecular profiling of this RGNT suggests that MAPK pathway and methylome changes, driven by KIAA1549:BRAF fusion and MLL2 mutation, respectively, could be associated with the development of this rare tumor entity. PMID:26371886

  8. Molecular Profiling of a Rare Rosette-Forming Glioneuronal Tumor Arising in the Spinal Cord.

    PubMed

    Bidinotto, Lucas Tadeu; Scapulatempo-Neto, Cristovam; Mackay, Alan; de Almeida, Gisele Caravina; Scheithauer, Bernd Walter; Berardinelli, Gustavo Noriz; Torrieri, Raul; Clara, Carlos Afonso; Feltrin, Leonir Terezinha; Viana-Pereira, Marta; Varella-Garcia, Marileila; Jones, Chris; Reis, Rui Manuel

    2015-01-01

    Rosette-forming glioneuronal tumor (RGNT) of the IV ventricle is a rare and recently recognized brain tumor entity. It is histologically composed by two distinct features: a glial component, resembling pilocytic astrocytoma, and a component forming neurocytic rosettes and/or perivascular rosettes. Herein, we describe a 33-year-old man with RGNT arising in the spinal cord. Following an immunohistochemistry validation, we further performed an extensive genomic analysis, using array-CGH (aCGH), whole exome and cancer-related hotspot sequencing, in order to better understand its underlying biology. We observed the loss of 1p and gain of 1q, as well as gain of the whole chromosomes 7, 9 and 16. Local amplifications in 9q34.2 and 19p13.3 (encompassing the gene SBNO2) were identified. Moreover, we observed focal gains/losses in several chromosomes. Additionally, on chromosome 7, we identified the presence of the KIAA1549:BRAF gene fusion, which was further validated by RT-PCR and FISH. Across all mutational analyses, we detected and validated the somatic mutations of the genes MLL2, CNNM3, PCDHGC4 and SCN1A. Our comprehensive molecular profiling of this RGNT suggests that MAPK pathway and methylome changes, driven by KIAA1549:BRAF fusion and MLL2 mutation, respectively, could be associated with the development of this rare tumor entity. PMID:26371886

  9. Maass Forms and Quantum Modular Forms

    NASA Astrophysics Data System (ADS)

    Rolen, Larry

    This thesis describes several new results in the theory of harmonic Maass forms and related objects. Maass forms have recently led to a flood of applications throughout number theory and combinatorics in recent years, especially following their development by the work of Bruinier and Funke the modern understanding Ramanujan's mock theta functions due to Zwegers. The first of three main theorems discussed in this thesis concerns the integrality properties of singular moduli. These are well-known to be algebraic integers, and they play a beautiful role in complex multiplication and explicit class field theory for imaginary quadratic fields. One can also study "singular moduli" for special non-holomorphic functions, which are algebraic but are not necessarily algebraic integers. Here we will explain the phenomenon of integrality properties and provide a sharp bound on denominators of symmetric functions in singular moduli. The second main theme of the thesis concerns Zagier's recent definition of a quantum modular form. Since their definition in 2010 by Zagier, quantum modular forms have been connected to numerous different topics such as strongly unimodal sequences, ranks, cranks, and asymptotics for mock theta functions. Motivated by Zagier's example of the quantum modularity of Kontsevich's "strange" function F(q), we revisit work of Andrews, Jimenez-Urroz, and Ono to construct a natural vector-valued quantum modular form whose components. The final chapter of this thesis is devoted to a study of asymptotics of mock theta functions near roots of unity. In his famous deathbed letter, Ramanujan introduced the notion of a mock theta function, and he offered some alleged examples. The theory of mock theta functions has been brought to fruition using the framework of harmonic Maass forms, thanks to Zwegers. Despite this understanding, little attention has been given to Ramanujan's original definition. Here we prove that Ramanujan's examples do indeed satisfy his

  10. Method for forming ammonia

    DOEpatents

    Kong, Peter C.; Pink, Robert J.; Zuck, Larry D.

    2008-08-19

    A method for forming ammonia is disclosed and which includes the steps of forming a plasma; providing a source of metal particles, and supplying the metal particles to the plasma to form metal nitride particles; and providing a substance, and reacting the metal nitride particles with the substance to produce ammonia, and an oxide byproduct.

  11. Methods of forming steel

    DOEpatents

    Branagan, Daniel J.; Burch, Joseph V.

    2001-01-01

    In one aspect, the invention encompasses a method of forming a steel. A metallic glass is formed and at least a portion of the glass is converted to a crystalline steel material having a nanocrystalline scale grain size. In another aspect, the invention encompasses another method of forming a steel. A molten alloy is formed and cooled the alloy at a rate which forms a metallic glass. The metallic glass is devitrified to convert the glass to a crystalline steel material having a nanocrystalline scale grain size. In yet another aspect, the invention encompasses another method of forming a steel. A first metallic glass steel substrate is provided, and a molten alloy is formed over the first metallic glass steel substrate to heat and devitrify at least some of the underlying metallic glass of the substrate.

  12. Forming of superplastic ceramics

    SciTech Connect

    Lesuer, D.R.; Wadsworth, J.; Nieh, T.G.

    1994-05-01

    Superplasticity in ceramics has now advanced to the stage that technologically viable superplastic deformation processing can be performed. In this paper, examples of superplastic forming and diffusion bonding of ceramic components are given. Recent work in biaxial gas-pressure forming of several ceramics is provided. These include yttria-stabilized, tetragonal zirconia (YTZP), a 20% alumina/YTZP composite, and silicon. In addition, the concurrent superplastic forming and diffusion bonding of a hybrid ceramic-metal structure are presented. These forming processes offer technological advantages of greater dimensional control and increased variety and complexity of shapes than is possible with conventional ceramic shaping technology.

  13. [Benign bone forming tumors].

    PubMed

    Caufourier, C; Leprovost, N; Guillou-Jamard, M-R; Compère, J-F; Bénateau, H

    2009-09-01

    Benign bone forming tumors typically produce dense bone (osteoma, enostosis) or osteoid tissue (osteoid osteoma, osteoblastoma). Even though these four lesions have distinct characteristics, it is sometimes difficult to tell them apart and to rule out malignant bone forming lesions such as osteosarcoma. The first line treatment is surgical exeresis.

  14. Method of forming nanodielectrics

    DOEpatents

    Tuncer, Enis [Knoxville, TN; Polyzos, Georgios [Oak Ridge, TN

    2014-01-07

    A method of making a nanoparticle filled dielectric material. The method includes mixing nanoparticle precursors with a polymer material and reacting the nanoparticle mixed with the polymer material to form nanoparticles dispersed within the polymer material to form a dielectric composite.

  15. Method for forming materials

    DOEpatents

    Tolle, Charles R.; Clark, Denis E.; Smartt, Herschel B.; Miller, Karen S.

    2009-10-06

    A material-forming tool and a method for forming a material are described including a shank portion; a shoulder portion that releasably engages the shank portion; a pin that releasably engages the shoulder portion, wherein the pin defines a passageway; and a source of a material coupled in material flowing relation relative to the pin and wherein the material-forming tool is utilized in methodology that includes providing a first material; providing a second material, and placing the second material into contact with the first material; and locally plastically deforming the first material with the material-forming tool so as mix the first material and second material together to form a resulting material having characteristics different from the respective first and second materials.

  16. Handprinted Forms and Characters

    National Institute of Standards and Technology Data Gateway

    NIST Handprinted Forms and Characters (PC database for purchase)   NIST Special Database 19 contains NIST's entire corpus of training materials for handprinted document and character recognition. It supersedes NIST Special Databases 3 and 7.

  17. Image forming apparatus

    DOEpatents

    Satoh, Hisao; Haneda, Satoshi; Ikeda, Tadayoshi; Morita, Shizuo; Fukuchi, Masakazu

    1996-01-01

    In an image forming apparatus having a detachable process cartridge in which an image carrier on which an electrostatic latent image is formed, and a developing unit which develops the electrostatic latent image so that a toner image can be formed, both integrally formed into one unit. There is provided a developer container including a discharge section which can be inserted into a supply opening of the developing unit, and a container in which a predetermined amount of developer is contained, wherein the developer container is provided to the toner supply opening of the developing unit and the developer is supplied into the developing unit housing when a toner stirring screw of the developing unit is rotated.

  18. Forms of Arthritis

    MedlinePlus

    ... It typically begins during the early-adult years. Juvenile arthritis — arthritis that is diagnosed before age 16. The most common form of juvenile arthritis, juvenile rheumatoid arthritis, affects between 30,000 and ...

  19. Electromagnetic nucleon form factors

    SciTech Connect

    Bender, A.; Roberts, C.D.; Frank, M.R.

    1995-08-01

    The Dyson-Schwinger equation framework is employed to obtain expressions for the electromagnetic nucleon form factor. In generalized impulse approximation the form factor depends on the dressed quark propagator, the dressed quark-photon vertex, which is crucial to ensuring current conservation, and the nucleon Faddeev amplitude. The approach manifestly incorporates the large space-like-q{sup 2} renormalization group properties of QCD and allows a realistic extrapolation to small space-like-q{sup 2}. This extrapolation allows one to relate experimental data to the form of the quark-quark interaction at small space-like-q{sup 2}, which is presently unknown. The approach provides a means of unifying, within a single framework, the treatment of the perturbative and nonperturbative regimes of QCD. The wealth of experimental nucleon form factor data, over a large range of q{sup 2}, ensures that this application will provide an excellent environment to test, improve and extend our approach.

  20. Comparative waste forms study

    SciTech Connect

    Wald, J.W.; Lokken, R.O.; Shade, J.W.; Rusin, J.M.

    1980-12-01

    A number of alternative process and waste form options exist for the immobilization of nuclear wastes. Although data exists on the characterization of these alternative waste forms, a straightforward comparison of product properties is difficult, due to the lack of standardized testing procedures. The characterization study described in this report involved the application of the same volatility, mechanical strength and leach tests to ten alternative waste forms, to assess product durability. Bulk property, phase analysis and microstructural examination of the simulated products, whose waste loading varied from 5% to 100% was also conducted. The specific waste forms investigated were as follows: Cold Pressed and Sintered PW-9 Calcine; Hot Pressed PW-9 Calcine; Hot Isostatic Pressed PW-9 Calcine; Cold Pressed and Sintered SPC-5B Supercalcine; Hot Isostatic pressed SPC-5B Supercalcine; Sintered PW-9 and 50% Glass Frit; Glass 76-68; Celsian Glass Ceramic; Type II Portland Cement and 10% PW-9 Calcine; and Type II Portland Cement and 10% SPC-5B Supercalcine. Bulk property data were used to calculate and compare the relative quantities of waste form volume produced at a spent fuel processing rate of 5 metric ton uranium/day. This quantity ranged from 3173 L/day (5280 Kg/day) for 10% SPC-5B supercalcine in cement to 83 L/day (294 Kg/day) for 100% calcine. Mechanical strength, volatility, and leach resistance tests provide data related to waste form durability. Glass, glass-ceramic and supercalcine ranked high in waste form durability where as the 100% PW-9 calcine ranked low. All other materials ranked between these two groupings.

  1. Major trends in stem anatomy and growth forms in the perianth-bearing Piperales, with special focus on Aristolochia

    PubMed Central

    Wagner, Sarah T.; Hesse, Linnea; Isnard, Sandrine; Samain, Marie-Stéphanie; Bolin, Jay; Maass, Erika; Neinhuis, Christoph; Rowe, Nick P.; Wanke, Stefan

    2014-01-01

    Background and Aims The order Piperales has the highest diversity of growth forms among the earliest angiosperm lineages, including trees, shrubs, climbers and herbs. However, within the perianth-bearing Piperales (Asarum, Saruma, Lactoris, Hydnora, Prosopanche, Thottea and Aristolochia), climbing species only occur in the most species-rich genus Aristolochia. This study traces anatomical and morphological traits among these lineages, to detect trends in growth form evolution and developmental processes. Methods Transverse stem sections of different developmental stages of representatives of Asarum, Saruma, Lactoris, Hydnora, Thottea and Aristolochia were compared and anatomical traits were linked to growth form evolution. Biomechanical properties of representative climbers were determined in three-point bending tests and are discussed based on the anatomical observations. Growth form evolution of the perianth-bearing Piperales was reconstructed by ancestral character state reconstruction using Mesquite. Key Results While species of Asarum and Saruma are exclusively herbaceous, species of the remaining genera show a higher diversity of growth habit and anatomy. This growth form diversity is accompanied by a more complex stem anatomy and appropriate biomechanical properties. The ancestral growth form of the perianth-bearing Piperales is reconstructed with either a shrub-like or herbaceous character state, while the following three backbone nodes in the reconstruction show a shrub-like character state. Accordingly, the climbing habit most probably evolved in the ancestor of Aristolochia. Conclusions Since the ancestor of the perianth-bearing Piperales has been reconstructed with a herb- or shrub-like habit, it is proposed that the climbing habit is a derived growth form, which evolved with the diversification of Aristolochia, and might have been a key feature for its diversification. Observed anatomical synapomorphies, such as the perivascular fibres in Lactoris

  2. Gnatophyma - A rare form of rosacea*

    PubMed Central

    de Macedo, Ana Carolina Lisboa; Sakai, Fernanda Dias Pacheco; de Vasconcelos, Rossana Cantanhede Farias; Duarte, Artur Antonio

    2012-01-01

    Phyma is the last stage of rosacea and is due to chronic inflammation and edema. It can affect nose (rhinophyma), chin (gnatophyma), forehead (metophyma), ears (otophyma) and eyelids (blepharophyma). Rhinophyma is the most frequent location and there are few reports about gnatophyma. We report the case of a female patient, 41 years old, who had an infiltrated, erythematous, edematous plaque around the chin and lower lip for two years. Histopathology showed perivascular lymphocytic infiltrate, hypertrophied follicles and sebaceous glands, dilated vessels and fibrosis. She was treated with oral tetracycline, oral ivermectin and metronidazole cream with a satisfactory response. The clinical, histopathological and therapeutic response correlation confirmed the diagnosis of gnatophyma, a rare variant of phyma. PMID:23197212

  3. Methods for forming particles

    DOEpatents

    Fox, Robert V.; Zhang, Fengyan; Rodriguez, Rene G.; Pak, Joshua J.; Sun, Chivin

    2016-06-21

    Single source precursors or pre-copolymers of single source precursors are subjected to microwave radiation to form particles of a I-III-VI.sub.2 material. Such particles may be formed in a wurtzite phase and may be converted to a chalcopyrite phase by, for example, exposure to heat. The particles in the wurtzite phase may have a substantially hexagonal shape that enables stacking into ordered layers. The particles in the wurtzite phase may be mixed with particles in the chalcopyrite phase (i.e., chalcopyrite nanoparticles) that may fill voids within the ordered layers of the particles in the wurtzite phase thus produce films with good coverage. In some embodiments, the methods are used to form layers of semiconductor materials comprising a I-III-VI.sub.2 material. Devices such as, for example, thin-film solar cells may be fabricated using such methods.

  4. Method for forming targets

    DOEpatents

    Woerner, Robert L.

    1979-01-01

    Method for cryoinduced uniform deposition of cryogenic materials, such as deuterium-tritium (DT) mixtures, on the inner surface of hollow spherical members, such as inertially imploded targets. By vaporizing and quickly refreezing cryogenic materials contained within a hollow spherical member, a uniform layer of the materials is formed on the inner surface of the spherical member. Heating of the cryogenic material, located within a non-isothermal compact freezing cell, is accomplished by an electrical heat pulse, whereafter the material is quickly frozen forming a uniform layer on the inner surface of the spherical member. The method is not restricted to producing a frozen layer on only the inner surface of the innermost hollow member, but where multiple concentric hollow spheres are involved, such as in multiple shell targets for lasers, electron beams, etc., layers of cryogenic material may also be formed on the inner surface of intermediate or outer spherical members, thus providing the capability of forming targets having multiple concentric layers or shells of frozen DT.

  5. Apparatus for forming targets

    DOEpatents

    Woerner, Robert L.

    1980-01-01

    Apparatus and method for cryoinduced uniform deposition of cryogenic materials, such as deuterium-tritium (DT) mixtures, on the inner surface of hollow spherical members, such as inertially imploded targets. By vaporizing and quickly refreezing cryogenic materials contained within a hollow spherical member, a uniform layer of the materials is formed on the inner surface of the spherical member. Heating of the cryogenic material, located within a non-isothermal compact freezing cell, is accomplished by an electrical heat pulse, whereafter the material is quickly frozen forming a uniform layer on the inner surface of the spherical member. The method is not restricted to producing a frozen layer on only the inner surface of the innermost hollow member, but where multiple concentric hollow spheres are involved, such as in multiple shell targets for lasers, electron beams, etc., layers of cryogenic material may also be formed on the inner surface of intermediate or outer spherical members, thus providing the capability of forming targets having multiple concentric layers or shells of frozen DT.

  6. Many Forms of Culture

    ERIC Educational Resources Information Center

    Cohen, Adam B.

    2009-01-01

    Psychologists interested in culture have focused primarily on East-West differences in individualism-collectivism, or independent-interdependent self-construal. As important as this dimension is, there are many other forms of culture with many dimensions of cultural variability. Selecting from among the many understudied cultures in psychology,…

  7. Geodiversity and land form

    NASA Astrophysics Data System (ADS)

    Gray, Murray

    2014-05-01

    The Earth's surface has a dynamic and topographically varied natural landscape. In some cases the resulting landforms are given generic names reflecting their form and/or origin, (e.g. sand dunes, eskers, ox-bow lakes) but in many cases the land surface has a more amorphous form and is less easily categorized other than at a landscape scale (e.g. dissected plateau, Chalk downland). Across much of Europe, while the natural vegetation has been removed or radically modified, the natural land form/topography remains in tact. In this context and in terms of geoconservation we ought to be: • allowing the dynamic natural processes that create, carve and modify landscapes to continue to operate; and • retaining natural topographic character and geomorphological authenticity in the face of human actions seeking to remodel the land surface. In this presentation examples of this approach to geoconservation of land form will be given from the UK and other parts of the world. This will include examples of both appropriate and inappropriate topographic modifications.

  8. Literature: External Forms.

    ERIC Educational Resources Information Center

    Regional Curriculum Project, Atlanta, GA.

    This curriculum guide, developed as part of a total English curriculum for pre-kindergarten through grade 10, suggests that students can best understand literature by understanding its recurring external forms or genres, and includes (1) an overview describing the four literary genres of drama, narrative poetry, narrative fiction, and lyric poetry…

  9. Formed photovoltaic module busbars

    DOEpatents

    Rose, Douglas; Daroczi, Shan; Phu, Thomas

    2015-11-10

    A cell connection piece for a photovoltaic module is disclosed herein. The cell connection piece includes an interconnect bus, a plurality of bus tabs unitarily formed with the interconnect bus, and a terminal bus coupled with the interconnect bus. The plurality of bus tabs extend from the interconnect bus. The terminal bus includes a non-linear portion.

  10. Forms of Soft Sculpture

    ERIC Educational Resources Information Center

    Tucker, Dorothy

    1978-01-01

    For the past several years, students at Madison Senior High School in San Diego have responded to the tactile texture and draping quality of soft materials. They experimented enthusiastically with three-dimensional forms made out of foam rubber. Here is the result of their efforts and experimentation. (Author/RK)

  11. Inelastic Scattering Form Factors

    1992-01-01

    ATHENA-IV computes form factors for inelastic scattering calculations, using single-particle wave functions that are eigenstates of motion in either a Woods-Saxon potential well or a harmonic oscillator well. Two-body forces of Gauss, Coulomb, Yukawa, and a sum of cut-off Yukawa radial dependences are available.

  12. High energy forming facility

    NASA Technical Reports Server (NTRS)

    Ciurlionis, B.

    1967-01-01

    Watertight, high-explosive forming facility, 25 feet in diameter and 15 feet deep, withstands repeated explosions of 10 pounds of TNT equivalent. The shell is fabricated of high strength steel and allows various structural elements to deform or move elastically and independently while retaining structural integrity.

  13. Low Temperature Sheet Forming

    NASA Astrophysics Data System (ADS)

    Voges-Schwieger, Kathrin; Hübner, Sven; Behrens, Bernd-Arno

    2011-05-01

    Metastable austenitic stainless steels change their lattice during forming operations by strain-induced alpha'-martensite formation. Temperatures below T = 20° C can accelerate the phase transformation while temperatures above T = 60° C may suppress the formation of martensite during the forming operation. In past investigations, the effect of high-strength martensitic regions in an austenitic ductile lattice was used in crash relevant parts for transportation vehicles. The local martensitic regions act as reinforcements leading to an increase in crash energy absorption. Moreover, they control the folding behavior as well as the force-distance-characteristic and increase the buckling resistance. This paper deals with a concerted thermomechanical drawing process to increase the local formation of alpha'-martensite caused by low temperatures.

  14. Analytic pion form factor

    NASA Astrophysics Data System (ADS)

    Lomon, Earle L.; Pacetti, Simone

    2016-09-01

    The pion electromagnetic form factor and two-pion production in electron-positron collisions are simultaneously fitted by a vector dominance model evolving to perturbative QCD at large momentum transfer. This model was previously successful in simultaneously fitting the nucleon electromagnetic form factors (spacelike region) and the electromagnetic production of nucleon-antinucleon pairs (timelike region). For this pion case dispersion relations are used to produce the analytic connection of the spacelike and timelike regions. The fit to all the data is good, especially for the newer sets of timelike data. The description of high-q2 data, in the timelike region, requires one more meson with ρ quantum numbers than listed in the 2014 Particle Data Group review.

  15. Waste-form development

    SciTech Connect

    Neilson, R.M. Jr.; Colombo, P.

    1982-01-01

    Contemporary solidification agents are being investigated relative to their applications to major fuel cycle and non-fuel cycle low-level waste (LLW) streams. Work is being conducted to determine the range of conditions under which these solidification agents can be applied to specific LLW streams. These studies are directed primarily towards defining operating parameters for both improved solidification of problem wastes and solidification of new LLW streams generated from advanced volume reduction technologies. Work is being conducted to measure relevant waste form properties. These data will be compiled and evaluated to demonstrate compliance with waste form performance and shallow land burial acceptance criteria and transportation requirements (both as they exist and as they are modified with time).

  16. Formed HIP Can Processing

    SciTech Connect

    Clarke, Kester Diederik

    2015-07-27

    The intent of this report is to document a procedure used at LANL for HIP bonding aluminum cladding to U-10Mo fuel foils using a formed HIP can for the Domestic Reactor Conversion program in the NNSA Office of Material, Management and Minimization, and provide some details that may not have been published elsewhere. The HIP process is based on the procedures that have been used to develop the formed HIP can process, including the baseline process developed at Idaho National Laboratory (INL). The HIP bonding cladding process development is summarized in the listed references. Further iterations with Babcock & Wilcox (B&W) to refine the process to meet production and facility requirements is expected.

  17. Conjunctive visual forms.

    PubMed

    Weaver, Chris

    2009-01-01

    Visual exploration of multidimensional data is a process of isolating and extracting relationships within and between dimensions. Coordinated multiple view approaches are particularly effective for visual exploration because they support precise expression of heterogeneous multidimensional queries using simple interactions. Recent visual analytics research has made significant progress in identifying and understanding patterns of composed views and coordinations that support fast, flexible, and open-ended data exploration. What is missing is formalization of the space of expressible queries in terms of visual representation and interaction. This paper introduces the Conjunctive Visual Form model in which visual exploration consists of interactively-driven sequences of transitions between visual states that correspond to conjunctive normal forms in boolean logic. The model predicts several new and useful ways to extend the space of rapidly expressible queries through addition of simple interactive capabilities to existing compositional patterns. Two recent related visual tools offer a subset of these capabilities, providing a basis for conjecturing about such extensions.

  18. Tube-Forming Assays.

    PubMed

    Brown, Ryan M; Meah, Christopher J; Heath, Victoria L; Styles, Iain B; Bicknell, Roy

    2016-01-01

    Angiogenesis involves the generation of new blood vessels from the existing vasculature and is dependent on many growth factors and signaling events. In vivo angiogenesis is dynamic and complex, meaning assays are commonly utilized to explore specific targets for research into this area. Tube-forming assays offer an excellent overview of the molecular processes in angiogenesis. The Matrigel tube forming assay is a simple-to-implement but powerful tool for identifying biomolecules involved in angiogenesis. A detailed experimental protocol on the implementation of the assay is described in conjunction with an in-depth review of methods that can be applied to the analysis of the tube formation. In addition, an ImageJ plug-in is presented which allows automatic quantification of tube images reducing analysis times while removing user bias and subjectivity.

  19. Certification reporting forms

    SciTech Connect

    Not Available

    1981-02-18

    The required information and formats for the certification report including the cover sheet, compliance statement, and body of the report are given in this document. The body of the reports is different for each product. There are no product-to-product differences in the forms of the other parts of the reports. The products covered in this document include: furnaces, water heaters, refrigerator-freezers, central air conditioners, room air conditioners, and freezers.

  20. Nucleon Electromagnetic Form Factors

    SciTech Connect

    Kees de Jager

    2004-08-01

    Although nucleons account for nearly all the visible mass in the universe, they have a complicated structure that is still incompletely understood. The first indication that nucleons have an internal structure, was the measurement of the proton magnetic moment by Frisch and Stern (1933) which revealed a large deviation from the value expected for a point-like Dirac particle. The investigation of the spatial structure of the nucleon, resulting in the first quantitative measurement of the proton charge radius, was initiated by the HEPL (Stanford) experiments in the 1950s, for which Hofstadter was awarded the 1961 Nobel prize. The first indication of a non-zero neutron charge distribution was obtained by scattering thermal neutrons off atomic electrons. The recent revival of its experimental study through the operational implementation of novel instrumentation has instigated a strong theoretical interest. Nucleon electro-magnetic form factors (EMFFs) are optimally studied through the exchange of a virtual photon, in elastic electron-nucleon scattering. The momentum transferred to the nucleon by the virtual photon can be selected to probe different scales of the nucleon, from integral properties such as the charge radius to scaling properties of its internal constituents. Polarization instrumentation, polarized beams and targets, and the measurement of the polarization of the recoiling nucleon have been essential in the accurate separation of the charge and magnetic form factors and in studies of the elusive neutron charge form factor.

  1. Electromagnetic pion form factor

    SciTech Connect

    Roberts, C.D.

    1995-08-01

    A phenomenological Dyson-Schwinger/Bethe-Salpeter equation approach to QCD, formalized in terms of a QCD-based model field theory, the Global Color-symmetry Model (GCM), was used to calculate the generalized impulse approximation contribution to the electromagnetic pion form factor at space-like q{sup 2} on the domain [0,10] GeV{sup 2}. In effective field theories this form factor is sometimes understood as simply being due to Vector Meson Dominance (VMD) but this does not allow for a simple connection with QCD where the VMD contribution is of higher order than that of the quark core. In the GCM the pion is treated as a composite bound state of a confined quark and antiquark interacting via the exchange of colored vector-bosons. A direct study of the quark core contribution is made, using a quark propagator that manifests the large space-like-q{sup 2} properties of QCD, parameterizes the infrared behavior and incorporates confinement. It is shown that the few parameters which characterize the infrared form of the quark propagator may be chosen so as to yield excellent agreement with the available data. In doing this one directly relates experimental observables to properties of QCD at small space-like-q{sup 2}. The incorporation of confinement eliminates endpoint and pinch singularities in the calculation of F{sub {pi}}(q{sup 2}). With asymptotic freedom manifest in the dressed quark propagator the calculation yields q{sup 4}F{sub {pi}}(q{sup 2}) = constant, up to [q{sup 2}]- corrections, for space-like-q{sup 2} {approx_gt} 35 GeV{sup 2}, which indicates that soft, nonperturbative contributions dominate the form factor at presently accessible q{sup 2}. This means that the often-used factorization Ansatz fails in this exclusive process. A paper describing this work was submitted for publication. In addition, these results formed the basis for an invited presentation at a workshop on chiral dynamics and will be published in the proceedings.

  2. 78 FR 58605 - Proposed Collection; Comment Request for Form 8453-EMP, Form 8453-F, Form 8453-FE, Form 8879-F...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-24

    ... Internal Revenue Service Proposed Collection; Comment Request for Form 8453-EMP, Form 8453-F, Form 8453-FE, Form 8879-F, and 8879-EMP. AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Notice and request...- file Return; Form 8453-EMP, Employment Tax Declaration for an IRS e- file Return; Form 8879-EMP, IRS...

  3. [Adhesive cutaneous pharmaceutical forms].

    PubMed

    Gafiţanu, E; Matei, I; Mungiu, O C; Pavelescu, M; Mîndreci, I; Apostol, I; Ionescu, G

    1989-01-01

    The adhesive cutaneous pharmaceutical forms aimed to local action release the drug substance in view of a dermatological, traumatological, antirheumatic, cosmetic action. Two such preparations were obtained and their stability, consistency and pH were determined. The "in vitro" tests of their bioavailability revealed the dynamics of calcium ions release according to the associations of each preparation. The bioavailability determined by evaluating the pharmacological response demonstrated the antiinflammatory action obtained by the association of calcium ions with the components extracted from poplar muds. The therapeutical efficiency of the studied preparations has proved in the treatment of some sport injuries.

  4. Nucleon elastic form factors

    SciTech Connect

    D. Day

    2007-03-01

    The nucleon form factors are still the subject of active investigation even after an experimental effort spanning 50 years. This is because they are of critical importance to our understanding of the electromagnetic properties of nuclei and provide a unique testing ground for QCD motivated models of nucleon structure. Progress in polarized beams, polarized targets and recoil polarimetry have allowed an important and precise set of data to be collected over the last decade. I will review the experimental status of elastic electron scattering from the nucleon along with an outlook for future progress.

  5. GlassForm

    2011-09-16

    GlassForm is a software tool for generating preliminary waste glass formulas for a given waste stream. The software is useful because it reduces the number of verification melts required to develop a suitable additive composition. The software includes property models that calculate glass properties of interest from the chemical composition of the waste glass. The software includes property models for glass viscosity, electrical conductivity, glass transition temperature, and leach resistance as measured by the 7-daymore » product consistency test (PCT).« less

  6. Bipolar pulse forming line

    DOEpatents

    Rhodes, Mark A.

    2008-10-21

    A bipolar pulse forming transmission line module for linear induction accelerators having first, second, third, fourth, and fifth planar conductors which form an interleaved stack with dielectric layers between the conductors. Each conductor has a first end, and a second end adjacent an acceleration axis. The first and second planar conductors are connected to each other at the second ends, the fourth and fifth planar conductors are connected to each other at the second ends, and the first and fifth planar conductors are connected to each other at the first ends via a shorting plate adjacent the first ends. The third planar conductor is electrically connectable to a high voltage source, and an internal switch functions to short a high voltage from the first end of the third planar conductor to the first end of the fourth planar conductor to produce a bipolar pulse at the acceleration axis with a zero net time integral. Improved access to the switch is enabled by an aperture through the shorting plate and the proximity of the aperture to the switch.

  7. Cartilage-forming tumors.

    PubMed

    Qasem, Shadi A; DeYoung, Barry R

    2014-01-01

    Cartilage-forming tumors as a group are the most common primary bone tumors; this is largely due to the common occurrence of asymptomatic benign lesions such as osteochondroma and enchondroma. The common feature of these tumors is the presence of chondrocytic cells and the formation of cartilaginous tumor matrix. Some of these tumors are true neoplasms while others are hamartomas or developmental abnormalities. The morphologic heterogeneity of these tumors may be explained by a common multipotent mesenchymal cell differentiating along the lines of fetal-adult cartilage maturation. Recently mutations in IDH1 and IDH2 have been detected in a variety of benign and malignant cartilaginous tumors.(1-4.) PMID:24680178

  8. Nucleon Electromagnetic Form Factors

    SciTech Connect

    Marc Vanderhaeghen; Charles Perdrisat; Vina Punjabi

    2007-10-01

    There has been much activity in the measurement of the elastic electromagnetic proton and neutron form factors in the last decade, and the quality of the data has greatly improved by performing double polarization experiments, in comparison with previous unpolarized data. Here we review the experimental data base in view of the new results for the proton, and neutron, obtained at JLab, MAMI, and MIT-Bates. The rapid evolution of phenomenological models triggered by these high-precision experiments will be discussed, including the recent progress in the determination of the valence quark generalized parton distributions of the nucleon, as well as the steady rate of improvements made in the lattice QCD calculations.

  9. Pion form factor

    SciTech Connect

    Ryong Ji, C.; Pang, A.; Szczepaniak, A.

    1994-04-01

    It is pointed out that the correct criterion to define the legal PQCD contribution to the exclusive processes in the lightcone perturbative expansion should be based on the large off-shellness of the lightcone energy in the intermediate states. In the lightcone perturbative QCD calculation of the pion form factor, the authors find that the legal PQCD contribution defined by the lightcone energy cut saturates in the smaller Q{sup 2} region compared to that defined by the gluon four-momentum square cut. This is due to the contribution by the highly off-energy-shell gluons in the end point regions of the phase space, indicating that the gluon four-momentum-square cut may have cut too much to define the legal PQCD.

  10. Weird past tense forms.

    PubMed

    Xu, F; Pinker, S

    1995-10-01

    It is often assumed that children go through a stage in which they systematically overapply irregular past tense patterns to inappropriate verbs, as in wipe-wope, bring-brang, trick-truck, walk-has walken. Such errors have been interpreted both as reflecting over-use of minor grammatical rules (e.g. 'change i to a'), and as reflecting the operation of a connectionist pattern associator network that superimposes and blends patterns of various degrees of generality. But the actual rate, time course, and nature of these errors have never been documented. We analysed 20,000 past tense and participle usages from nine children in the CHILDES database, looking for overapplications of irregular vowel-change patterns, as in brang, blends, as in branged, productive suffixations of -en, as in walken, gross distortions, as in mail-membled, and double-suffixation, as in walkeded. These errors were collectively quite rare; children made them in about two tenths of one per cent of the opportunities, and with few stable patterns: the errors were not predominantly word-substitutions, did not occur predominantly with irregular stems, showed no consistency across verbs or ages, and showed no clear age trend. Most (though not all) of the errors were based closely on existing irregular verbs; gross distortions never occurred. We suggest that both rule-theories and connectionist theories have tended to overestimate the predominance of such errors. Children master irregular forms quite accurately, presumably because irregular forms are just a special case of the arbitrary sound-meaning pairings that define words, and because children are good at learning words.

  11. Forming Spirals From Shadows

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-07-01

    What causes the large-scale spiral structures found in some protoplanetary disks? Most models assume theyre created by newly-forming planets, but a new study suggests that planets might have nothing to do with it.Perturbations from Planets?In some transition disks protoplanetary disks with gaps in their inner regions weve directly imaged large-scale spiral arms. Many theories currently attribute the formation of these structures to young planets: either the direct perturbations of a planet embedded in the disk cause the spirals, or theyre indirectly caused by the orbit of a planetary body outside of the arms.Another example of spiral arms detected in a protoplanetary disk, MWC 758. [NASA/ESA/ESO/M. Benisty et al.]But what if you could get spirals without any planets? A team of scientists led by Matas Montesinos (University of Chile) have recently published a study in which they examine what happens to a shadowed protoplanetary disk.Casting Shadows with WarpsIn the teams setup, they envision a protoplanetary disk that is warped: the inner region is slightly tilted relative to the outer region. As the central star casts light out over its protoplanetary disk, this disk warping would cause some regions of the disk to be shaded in a way that isnt axially symmetric with potentially interesting implications.Montesinos and collaborators ran 2D hydrodynamics simulations to determine what happens to the motion of particles within the disk when they pass in and out of the shadowed regions. Since the shadowed regions are significantly colder than the illuminated disk, the pressure in these regions is much lower. Particles are therefore accelerated and decelerated as they pass through these regions, and the lack of axial symmetry causes spiral density waves to form in the disk as a result.Initial profile for the stellar heating rate per unit area for one of the authors simulations. The regions shadowed as a result of the disk warp subtend 0.5 radians each (shown on the left

  12. Moon (Form-Origin)

    NASA Astrophysics Data System (ADS)

    Tsiapas, Elias

    2016-04-01

    When the Earth was formed, it was in a state of burning heat. As time went by, temperature on the planet's surface was falling due to radiation and heat transfer, and various components (crusts) began taking solid form at the Earth's poles. The formation of crusts took place at the Earth's poles, because the stirring of burning and fluid masses on the surface of the Earth was significantly slighter there than it was on the equator. Due to centrifugal force and Coriolis Effect, these solid masses headed towards the equator; those originating from the North Pole followed a south-western course, while those originating from the South Pole followed a north-western course and there they rotated from west to east at a lower speed than the underlying burning and liquid earth, because of their lower initial linear velocity, their solid state and inertia. Because inertia is proportional to mass, the initially larger solid body swept all new solid ones, incorporating them to its western side. The density of the new solid masses was higher, because the components on the surface would freeze and solidify first, before the underlying thicker components. As a result, the western side of the initial islet of solid rocks submerged, while the east side elevated. . As a result of the above, this initial islet began to spin in reverse, and after taking on the shape of a sphere, it formed the "heart" of the Moon. The Moon-sphere, rolling on the equator, would sink the solid rocks that continued to descend from the Earth's poles. The sinking rocks partially melted because of higher temperatures in the greater depths that the Moon descended to, while part of the rocks' mass bonded with the Moon and also served as a heat-insulating material, preventing the descended side of the sphere from melting. Combined with the Earth's liquid mass that covered its emerging eastern surface, new sphere-shaped shells were created, with increased density and very powerful structural cohesion. During the

  13. Moon (Form-Origin)

    NASA Astrophysics Data System (ADS)

    Tsiapas, Elias

    2014-05-01

    When the Earth was formed, it was in a state of burning heat. As time went by, temperature on the planet's surface was falling due to radiation and heat transfer, and various components (crusts) began taking solid form at the Earth's poles. The formation of crusts took place at the Earth's poles, because the stirring of burning and fluid masses on the surface of the Earth was significantly slighter there than it was on the equator. Due to centrifugal force and Coriolis Effect, these solid masses headed towards the equator; those originating from the North Pole followed a south-western course, while those originating from the South Pole followed a north-western course and there they rotated from west to east at a lower speed than the underlying burning and liquid earth, because of their lower initial linear velocity, their solid state and inertia. Because inertia is proportional to mass, the initially larger solid body swept all new solid ones, incorporating them to its western side. The density of the new solid masses was higher, because the components on the surface would freeze and solidify first, before the underlying thicker components. As a result, the western side of the initial islet of solid rocks submerged, while the east side elevated. . As a result of the above, this initial islet began to spin in reverse, and after taking on the shape of a sphere, it formed the "heart" of the Moon. The Moon-sphere, rolling on the equator, would sink the solid rocks that continued to descend from the Earth's poles. The sinking rocks partially melted because of higher temperatures in the greater depths that the Moon descended to, while part of the rocks' mass bonded with the Moon and also served as a heat-insulating material, preventing the descended side of the sphere from melting. Combined with the Earth's liquid mass that covered its emerging eastern surface, new sphere-shaped shells were created, with increased density and very powerful structural cohesion. During the

  14. Moon (Form-Origin)

    NASA Astrophysics Data System (ADS)

    Tsiapas, Elias

    2013-04-01

    When the Earth was formed, it was in a state of burning heat. As time went by, temperature on the planet's surface was falling due to radiation and heat transfer, and various components (crusts) began taking solid form at the Earth's poles. The formation of crusts took place at the Earth's poles, because the stirring of burning and fluid masses on the surface of the Earth was significantly slighter there than it was on the equator. Due to centrifugal force and Coriolis Effect, these solid masses headed towards the equator; those originating from the North Pole followed a south-western course, while those originating from the South Pole followed a north-western course and there they rotated from west to east at a lower speed than the underlying burning and liquid earth, because of their lower initial linear velocity, their solid state and inertia. Because inertia is proportional to mass, the initially larger solid body swept all new solid ones, incorporating them to its western side. The density of the new solid masses was higher, because the components on the surface would freeze and solidify first, before the underlying thicker components. As a result, the western side of the initial islet of solid rocks submerged, while the east side elevated. As a result of the above, this initial islet began to spin in reverse, and after taking on the shape of a sphere, it formed the "heart" of the Moon. The Moon-sphere, rolling on the equator, would sink the solid rocks that continued to descend from the Earth's poles. The sinking rocks partially melted because of higher temperatures in the greater depths that the Moon descended to, while part of the rocks' mass bonded with the Moon and also served as a heat-insulating material, preventing the descended side of the sphere from melting. Combined with the Earth's liquid mass that covered its emerging eastern surface, new sphere-shaped shells were created, with increased density and very powerful structural cohesion. During the

  15. Moon (Form-Origin)

    NASA Astrophysics Data System (ADS)

    Tsiapas, Elias

    2015-04-01

    When the Earth was formed, it was in a state of burning heat. As time went by, temperature on the planet's surface was falling due to radiation and heat transfer, and various components (crusts) began taking solid form at the Earth's poles. The formation of crusts took place at the Earth's poles, because the stirring of burning and fluid masses on the surface of the Earth was significantly slighter there than it was on the equator. Due to centrifugal force and Coriolis Effect, these solid masses headed towards the equator; those originating from the North Pole followed a south-western course, while those originating from the South Pole followed a north-western course and there they rotated from west to east at a lower speed than the underlying burning and liquid earth, because of their lower initial linear velocity, their solid state and inertia. Because inertia is proportional to mass, the initially larger solid body swept all new solid ones, incorporating them to its western side. The density of the new solid masses was higher, because the components on the surface would freeze and solidify first, before the underlying thicker components. As a result, the western side of the initial islet of solid rocks submerged, while the east side elevated. . As a result of the above, this initial islet began to spin in reverse, and after taking on the shape of a sphere, it formed the "heart" of the Moon. The Moon-sphere, rolling on the equator, would sink the solid rocks that continued to descend from the Earth's poles. The sinking rocks partially melted because of higher temperatures in the greater depths that the Moon descended to, while part of the rocks' mass bonded with the Moon and also served as a heat-insulating material, preventing the descended side of the sphere from melting. Combined with the Earth's liquid mass that covered its emerging eastern surface, new sphere-shaped shells were created, with increased density and very powerful structural cohesion. During the

  16. Gas Giants Form Quickly

    NASA Technical Reports Server (NTRS)

    2007-01-01

    This is an artist's concept of a hypothetical 10-million-year-old star system. The bright blur at the center is a star much like our sun. The other orb in the image is a gas-giant planet like Jupiter. Wisps of white throughout the image represent traces of gas.

    Astronomers using NASA's Spitzer Space Telescope have found evidence showing that gas-giant planets either form within the first 10 million years of a sun-like star's life, or not at all. The lifespan for sun-like stars is about 10 billion years.

    The scientists came to this conclusion after searching for traces of gas around 15 different sun-like stars, most with ages ranging from 3 million to 30 million years. With the help of Spitzer's Infrared Spectrometer instrument, they were able to search for relatively warm gas in the inner regions of these star systems, an area comparable to the zone between Earth and Jupiter in our own solar system. They also used ground-based radio telescopes to search for cooler gas in the outer regions of these systems, an area comparable to the zone around Saturn and beyond.

  17. How delusion is formed?

    PubMed

    Park, Jong Suk; Kang, Ung Gu

    2016-02-01

    Traditionally, delusions have been considered to be the products of misinterpretation and irrationality. However, some theorists have argued that delusions are normal or rational cognitive responses to abnormal experiences. That is, when a recently experienced peculiar event is more plausibly explained by an extraordinary hypothesis, confidence in the veracity of this extraordinary explanation is reinforced. As the number of such experiences, driven by the primary disease process in the perceptual domain, increases, this confidence builds and solidifies, forming a delusion. We tried to understand the formation of delusions using a simulation based on Bayesian inference. We found that (1) even if a delusional explanation is only marginally more plausible than a non-delusional one, the repetition of the same experience results in a firm belief in the delusion. (2) The same process explains the systematization of delusions. (3) If the perceived plausibility of the explanation is not consistent but varies over time, the development of a delusion is delayed. Additionally, this model may explain why delusions are not corrected by persuasion or rational explanation. This Bayesian inference perspective can be considered a way to understand delusions in terms of rational human heuristics. However, such experiences of "rationality" can lead to irrational conclusions, depending on the characteristics of the subject. PMID:26826642

  18. Can polymersomes form colloidosomes?

    PubMed

    Thompson, Kate L; Chambon, Pierre; Verber, Robert; Armes, Steven P

    2012-08-01

    Hydroxy-functionalized polymersomes (or block copolymer vesicles) were prepared via a facile one-pot RAFT aqueous dispersion polymerization protocol and evaluated as Pickering emulsifiers for the stabilization of emulsions of n-dodecane emulsion droplets in water. Linear polymersomes produced polydisperse oil droplets with diameters of ~50 μm regardless of the polymersome concentration in the aqueous phase. Introducing an oil-soluble polymeric diisocyanate cross-linker into the oil phase prior to homogenization led to block copolymer microcapsules, as expected. However, TEM inspection of these microcapsules after an alcohol challenge revealed no evidence for polymersomes, suggesting these delicate nanostructures do not survive the high-shear emulsification process. Thus the emulsion droplets are stabilized by individual diblock copolymer chains, rather than polymersomes. Cross-linked polymersomes (prepared by the addition of ethylene glycol dimethacrylate as a third comonomer) also formed stable n-dodecane-in-water Pickering emulsions, as judged by optical and fluorescence microscopy. However, in this case the droplet diameter varied from 50 to 250 μm depending on the aqueous polymersome concentration. Moreover, diisocyanate cross-linking at the oil/water interface led to the formation of well-defined colloidosomes, as judged by TEM studies. Thus polymersomes can indeed stabilize colloidosomes, provided that they are sufficiently cross-linked to survive emulsification.

  19. Tautomeric Forms of Metarhodopsin

    PubMed Central

    Matthews, Rowena G.; Hubbard, Ruth; Brown, Paul K.; Wald, George

    1963-01-01

    Light isomerizes the chromophore of rhodopsin, 11-cis retinal (formerly retinene), to the all-trans configuration. This introduces a succession of unstable intermediates—pre-lumirhodopsin, lumirhodopsin, metarhodopsin —in which all-trans retinal is still attached to the chromophoric site on opsin. Finally, retinal is hydrolyzed from opsin. The present experiments show that metarhodopsin exists in two tautomeric forms, metarhodopsins I and II, with λmax 478 and 380 mµ. Metarhodopsin I appears first, then enters into equilibrium with metarhodopsin II. In this equilibrium, the proportion of metarhodopsin II is favored by higher temperature or pH, neutral salts, and glycerol. The change from metarhodopsin I to II involves the binding of a proton by a group with pK 6.4 (imidazole?), and a large increase of entropy. Metarhodopsin II has been confused earlier with the final mixture of all-trans retinal and opsin (λmax 387 mµ), which it resembles in spectrum. These two products are, however, readily distinguished experimentally. PMID:14080814

  20. New education coalition formed

    NASA Astrophysics Data System (ADS)

    Watt Ireto, M. Frank

    The Coalition for Earth Science Education (CESE) was recently formed to promote Earth science education at all levels. Earth science is a diverse group of sciences and as a result, professional and academic organizations from the various areas, though united in their goal to stimulate student enthusiasm for the Earth sciences, have not had an effective way of reaching students or their precollege teachers. Over the past year, meetings sponsored by the National Academy of Science's Board on Earth Sciences and Resources and the National Science Foundation have paved the way for this coalition. Victor Mayer, Director of the Program for Leadership in Earth Systems Science (PLESE) project at the University of Ohio, has been the leader in initiating and promoting this effort for the last several years.The purpose of CESE is to promote communication among the member organizations and to coordinate projects in Earth science education. Individual organizations will continue to develop and run projects, but will be able to find out what types of projects others are working on or have completed through a coalition clearinghouse. The clearinghouse should aid organizations as they design projects and should afford opportunities for collaborative efforts. This will directly benefit teachers, who will be able to contact one source for information on the multitude of projects in the Earth and space sciences. The new coalition's steering committee is working on goals and guidelines, and will give a report at the next coalition meeting at the National Science Teachers Association annual convention in Boston.

  1. How desert varnish forms?

    NASA Astrophysics Data System (ADS)

    Perry, Randall S.; Kolb, Vera M.; Lynne, Bridget Y.; Sephton, Mark A.; Mcloughlin, Nicola; Engel, Michael H.; Olendzenski, Lorraine; Brasier, Martin; Staley, James T., Jr.

    2005-09-01

    Desert varnish is a black, manganese-rich rock coating that is widespread on Earth. The mechanism underlying its formation, however, has remained unresolved. We present here new data and an associated model for how desert varnish forms, which substantively challenges previously accepted models. We tested both inorganic processes (e.g. clays and oxides cementing coatings) and microbial methods of formation. Techniques used in this preliminary study include SEM-EDAX with backscatter, HRTEM of focused ion beam prepared (FIB) wafers and several other methods including XRPD, Raman spectroscopy, XPS and Tof-SIMS. The only hypothesis capable of explaining a high water content, the presence of organic compounds, an amorphous silica phase (opal-A) and lesser quantities of clays than previously reported, is a mechanism involving the mobilization and redistribution of silica. The discovery of silica in desert varnish suggests labile organics are preserved by interaction with condensing silicic acid. Organisms are not needed for desert varnish formation but Bacteria, Archaea, Eukarya, and other organic compounds are passively incorporated and preserved as organominerals. The rock coatings thus provide useful records of past environments on Earth and possibly other planets. Additionally this model also helps to explain the origin of key varnish and rock glaze features, including their hardness, the nature of the "glue" that binds heterogeneous components together, its layered botryoidal morphology, and its slow rate of formation.

  2. Symmetries of Helmholtz forms and globally variational dynamical forms

    NASA Astrophysics Data System (ADS)

    Palese, Marcella; Winterroth, Ekkehart

    2012-02-01

    Invariance properties of classes in the variational sequence suggested to Krupka et al. the idea that there should exist a close correspondence between the notions of variationality of a differential form and invariance of its exterior derivative. It was shown by them that the invariance of a closed Helmholtz form of a dynamical form is equivalent with local variationality of the Lie derivative of the dynamical form, so that the latter is locally the Euler-Lagrange form of a Lagrangian. We show that the corresponding local system of Euler-Lagrange forms is variationally equivalent to a global Euler-Lagrange form.

  3. Watching How Planets Form

    NASA Astrophysics Data System (ADS)

    2006-09-01

    Anatomy of a Planet-Forming Disc around a Star More Massive than the Sun With the VISIR instrument on ESO's Very Large Telescope, astronomers have mapped the disc around a star more massive than the Sun. The very extended and flared disc most likely contains enough gas and dust to spawn planets. It appears as a precursor of debris discs such as the one around Vega-like stars and thus provides the rare opportunity to witness the conditions prevailing prior to or during planet formation. "Planets form in massive, gaseous and dusty proto-planetary discs that surround nascent stars. This process must be rather ubiquitous as more than 200 planets have now been found around stars other than the Sun," said Pierre-Olivier Lagage, from CEA Saclay (France) and leader of the team that carried out the observations. "However, very little is known about these discs, especially those around stars more massive than the Sun. Such stars are much more luminous and could have a large influence on their disc, possibly quickly destroying the inner part." The astronomers used the VISIR instrument [1] on ESO's Very Large Telescope to map in the infrared the disc surrounding the young star HD 97048. With an age of a few million years [2], HD 97048 belongs to the Chameleon I dark cloud, a stellar nursery 600 light-years away. The star is 40 times more luminous than our Sun and is 2.5 times as massive. The astronomers could only have achieved such a detailed view due to the high angular resolution offered by an 8-metre size telescope in the infrared, reaching a resolution of 0.33 arcsecond. They discovered a very large disc, at least 12 times more extended than the orbit of the farthest planet in the Solar System, Neptune. The observations suggest the disc to be flared. "This is the first time such a structure, predicted by some theoretical models, is imaged around a massive star," said Lagage. ESO PR Photo 36/06 ESO PR Photo 36/06 A Flared Proto-Planetary Disc Such a geometry can only be

  4. Waste form product characteristics

    SciTech Connect

    Taylor, L.L.; Shikashio, R.

    1995-01-01

    The Department of Energy has operated nuclear facilities at the Idaho National Engineering Laboratory (INEL) to support national interests for several decades. Since 1953, it has supported the development of technologies for the storage and reprocessing of spent nuclear fuels (SNF) and the resultant wastes. However, the 1992 decision to discontinue reprocessing of SNF has left nearly 768 MT of SNF in storage at the INEL with unspecified plans for future dispositioning. Past reprocessing of these fuels for uranium and other resource recovery has resulted in the production of 3800 M{sup 3} calcine and a total inventory of 7600 M{sup 3} of radioactive liquids (1900 M{sup 3} destined for immediate calcination and the remaining sodium-bearing waste requiring further treatment before calcination). These issues, along with increased environmental compliance within DOE and its contractors, mandate operation of current and future facilities in an environmentally responsible manner. This will require satisfactory resolution of spent fuel and waste disposal issues resulting from the past activities. A national policy which identifies requirements for the disposal of SNF and high level wastes (HLW) has been established by the Nuclear Waste Policy Act (NWPA) Sec.8,(b) para(3)) [1982]. The materials have to be conditioned or treated, then packaged for disposal while meeting US Environmental Protection Agency (EPA) and Nuclear Regulatory Commission (NRC) regulations. The spent fuel and HLW located at the INEL will have to be put into a form and package that meets these regulatory criteria. The emphasis of Idaho Chemical Processing Plant (ICPP) future operations has shifted toward investigating, testing, and selecting technologies to prepare current and future spent fuels and waste for final disposal. This preparation for disposal may include mechanical, physical and/or chemical processes, and may differ for each of the various fuels and wastes.

  5. Science Grade 7, Long Form.

    ERIC Educational Resources Information Center

    New York City Board of Education, Brooklyn, NY. Bureau of Curriculum Development.

    The Grade 7 Science course of study was prepared in two parallel forms. A short form designed for students who had achieved a high measure of success in previous science courses; the long form for those who have not been able to maintain the pace. Both forms contain similar content. The Grade 7 guide is the first in a three-year sequence for…

  6. 10. VIEW SHOWING THE ARCH FORMS. THE INTRADOS FORM IS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. VIEW SHOWING THE ARCH FORMS. THE INTRADOS FORM IS COMMONLY LIFTED 3 TO 4 DAYS AFTER POURING. REINFORCING STEEL IS THEN PLACED AND THE EXTRADOS FORM RAISED TO POSITION. THE OPERATING OF MOVING FORMS, PLACING STEEL AND CONCRETE FOR EACH ARCH LIFT REQUIRES, ON AVERAGE, EIGHT DAYS. NOTE THE TWO LINES OF WATER PIPE ON THE EXTRADOS FORM. THESE PIPES ARE FILLED WITH SPRAY NOZZLES WHICH ARE IN PRACTICALLY CONTINUOUS OPERATION EXCEPT WHEN WORK IS BEING DONE ON THE FORMS. August 9, 1938 - Bartlett Dam, Verde River, Phoenix, Maricopa County, AZ

  7. Prominent Vascular and Perivascular Eosinophilic Infiltrates Heralding CNS Mycosis Fungoides.

    PubMed

    Schowinsky, Jeffrey; Leppert, Michelle; Ney, Douglas; Kleinschmidt-DeMasters, B K

    2015-10-01

    Brain parenchymal involvement of mycosis fungoides (MF) is very rare. This study reports a patient with known cutaneous MF (under treatment) who presented with a CNS syndrome and multiple brain lesions. Brain biopsy demonstrated massive eosinophilic infiltrates but no MF cells. Despite treatment, new lesions developed and the patient died. At autopsy, there was massive involvement MF cells, suggesting that the eosinophilic infiltrates presaged the severe involvement of the CNS by MF. PMID:26352990

  8. Form-definition language for an intelligent form

    SciTech Connect

    Honeyman, J.C.

    1987-01-01

    The formal specification of a form-definition language is described. A new form-based model for office automation is defined informally. The model is called the Intelligent Form System (IFS) and is composed of a knowledge base, a Synchronous Form Manager (SFM), and an Intelligent Form (IF). The IFS is designed to be a distributed system capable of being implemented using existing technology. The syntax for the form definition language (FDL) used to specify the contents and processing for an Intelligent Form is developed. The automatic processing and routing of the form based upon form content and system configuration is formally defined. A control graph describing the necessary routing to complete the form is constructed and a control process directs processing of the form using the control graph and a state table containing a history of form processing. Examples are used to illustrate the syntax of the FDL and the algorithms for construction of the control graph and control process. The end result is the informal definition of a new model and the formal definition of the form-definition language and control process.

  9. Heated die facilitates tungsten forming

    NASA Technical Reports Server (NTRS)

    Chattin, J. H.; Haystrick, J. E.; Laughlin, J. C.; Leidy, R. A.

    1966-01-01

    Tungsten forming in a press brake employs a bottom die assembly with a heating manifold between two water-cooled die sections. The manifold has hydrogen-oxygen burners spaced along its length for even heat during forming.

  10. Warm Forming of Mg Sheets: From Incremental to Electromagnetic Forming

    NASA Astrophysics Data System (ADS)

    Ulacia, Ibai; Galdos, Lander; Esnaola, Jon Ander; Larrañaga, Jon; Arruebarrena, Gurutze; de Argandoña, Eneko Saenz; Hurtado, Iñaki

    2014-07-01

    Magnesium alloys are generating interest in the automotive and aeronautic industries due to their low density and potential to reduce gross vehicular weight. However, the formability of these alloys is poor and they are very difficult to be formed at room temperature due to their strong basal texture in rolled form. In this paper, the potential of magnesium alloy sheets to be processed at warm conditions is studied for four different forming technologies: incremental forming (IF), deep drawing (DD), hydroforming (HF), and electromagnetic forming (EMF). Forming mechanisms and process window are experimentally characterized by monitoring different process parameters. Special focus is made on the influence of the forming temperature and the strain rate. Thus, experiments at temperatures from room to 523 K (250 °C) and a wide range of strain rates, between 10-3 up to 103 s-1 according to each process nature and scope, are conducted. It is observed that, even the inherent forming rate range of each process vary considerably, increasing forming temperature increases formability for all of these forming processes. In the other hand, an opposing effect of the strain rate is observed between the quasi-static processes (IF, DD, and HF) and the high speed process (EMF). Thus, a detrimental effect on formability is observed when increasing strain rate for quasi-static processes, while a mild increase is observed for EMF.

  11. Index of NASA prefixed forms

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This Handbook sets forth information for the guidance of all users of the NASA Forms Management Program System. It is issued in accordance with the Federal Information Resources Management Regulation (FIRMR), Subpart 201-9.1. This Handbook sets forth an alpha-functional index of NASA-prefixed forms by title, identifying number, and unit of issue. The automated processing two-letter code (NF) has been substituted for the spelling out of the NASA form-prefix preceding the form number. To indicate a description in lieu of a distinct title, the entire reference under the Form Title/Description column has been enclosed in parentheses. A list of current forms, shown by number and page, is included for cross-reference and to preclude the ordering of those forms which have been deleted from the system. This Handbook will be updated, as appropriate. NHB 1420.2H dated July 1986, is cancelled.

  12. Undercuts by Laser Shock Forming

    NASA Astrophysics Data System (ADS)

    Wielage, Hanna; Vollertsen, Frank

    2011-05-01

    In laser shock forming TEA-CO2-laser induced shock waves are used to form metal foils, such as aluminum or copper. The process utilizes an initiated plasma shock wave on the target surface, which leads to a forming of the foil. A challenge in forming technologies is the manufacturing of undercuts. By conventional forming methods these special forms are not feasible. In this article, it is presented that undercuts in the micro range can be produced by laser shock deep drawing. Different drawing die diameters, drawing die depths and the material aluminum in the thicknesses 20 and 50 μm were investigated. It will be presented that smaller die diameters facilitate undercuts compared to bigger die diameters. The phenomena can be explained by Barlow's formula. Furthermore, it is shown which maximum undercut depth at different die diameters can be reached. To this end, cross-sections of the different parameter combinations are displayed.

  13. The semantics of biological forms.

    PubMed

    Albertazzi, Liliana; Canal, Luisa; Dadam, James; Micciolo, Rocco

    2014-01-01

    This study analyses how certain qualitative perceptual appearances of biological forms are correlated with expressions of natural language. Making use of the Osgood semantic differential, we presented the subjects with 32 drawings of biological forms and a list of 10 pairs of connotative adjectives to be put in correlations with them merely by subjective judgments. The principal components analysis made it possible to group the semantics of forms according to two distinct axes of variability: harmony and dynamicity. Specifically, the nonspiculed, nonholed, and flat forms were perceived as harmonic and static; the rounded ones were harmonic and dynamic. The elongated forms were somewhat disharmonious and somewhat static. The results suggest the existence in the general population of a correspondence between perceptual and semantic processes, and of a nonsymbolic relation between visual forms and their adjectival expressions in natural language.

  14. Undercuts by Laser Shock Forming

    SciTech Connect

    Wielage, Hanna; Vollertsen, Frank

    2011-05-04

    In laser shock forming TEA-CO{sub 2}-laser induced shock waves are used to form metal foils, such as aluminum or copper. The process utilizes an initiated plasma shock wave on the target surface, which leads to a forming of the foil. A challenge in forming technologies is the manufacturing of undercuts. By conventional forming methods these special forms are not feasible. In this article, it is presented that undercuts in the micro range can be produced by laser shock deep drawing. Different drawing die diameters, drawing die depths and the material aluminum in the thicknesses 20 and 50 {mu}m were investigated. It will be presented that smaller die diameters facilitate undercuts compared to bigger die diameters. The phenomena can be explained by Barlow's formula. Furthermore, it is shown which maximum undercut depth at different die diameters can be reached. To this end, cross-sections of the different parameter combinations are displayed.

  15. Seal for fluid forming tools

    DOEpatents

    Golovashchenko, Sergey Fedorovich; Bonnen, John Joseph Francis

    2012-03-20

    An electro-hydraulic forming tool for forming a sheet metal blank in a one-sided die has first and second rigid rings that engage opposite sides of a sheet metal blank. The rigid rings are contained within slots on a die portion and a hydraulic force applicator portion of the forming tool. The seals are either resiliently biased by an elastomeric member or inherently resiliently biased into contact with the blank.

  16. Improving the forming capability of laser dynamic forming by using rubber as a forming medium

    NASA Astrophysics Data System (ADS)

    Shen, Zongbao; Liu, Huixia; Wang, Xiao; Wang, Cuntang

    2016-04-01

    Laser dynamic forming (LDF) is a novel high velocity forming technique, which employs laser-generated shock wave to load the sample. The forming velocity induced by the high energy laser pulse may exceed the critical forming velocity, resulting in the occurrence of premature fracture. To avoid the above premature fracture, rubber is introduced in LDF as a forming medium to prolong the loading duration in this paper. Laser induced shock wave energy is transferred to the sample in different forming stages, so the forming velocity can be kept below the critical forming velocity when the initial laser energy is high for fracture. Bulge forming experiments with and without rubber were performed to study the effect of rubber on loading duration. The experimental results show that, the shock wave energy attenuates during the propagation through the rubber layer, the rubber can avoid the premature fracture. So the plastic deformation can continue, the forming capability of LDF is improved. Due to the severe plastic deformation under rubber compression, adiabatic shear bands (ASB) occur in LDF with rubber. The material softening in ASB leads to the irregular fracture, which is different from the premature fracture pattern (regular fracture) in LDF without rubber. To better understand this deformation behavior, Johnson-Cook model is used to simulate the dynamic response and the evolution of ASB of copper sample. The simulation results also indicate the rubber can prolong the loading duration.

  17. Legal forms and reproductive norms.

    PubMed

    Fletcher, Ruth

    2003-06-01

    This article draws on Pashukanis's concept of legal form and on O'Brien's concept of synthetic value to argue that legal form plays a role in reproductive relations by constructing legal subjects as the bearers of reproductive responsibilities. Pashukanis conceived of legal form as playing a particular role in capitalist exchange relations by interpellating subjects as the bearers of property rights. O'Brien argued that reproduction's specific value is synthetic value, which represents the value of integrating nature and reason in species continuity. Synthetic value is distinct from exchange value or emotional value which may also attach to reproductive process. By working through Pashukanis's method of extracting legal form from specific social relations and by adapting it to reproductive relations, an example is provided of how legal form analysis can be extended beyond the particular context of capitalist exchange relations. Just as legal form constitutes owners and non-owners as legal subjects, so it constitutes reproducers and non-reproducers. By tracing the way in which law attributes reproductive responsibility, legal form analysis shows us how law draws a line between wanting to attribute responsibility and not to attribute it, and this contradiction is a hook which social forces such as sexuality, gender, race, class and disability can latch on to in pushing legal form to shape reproductive responsibilities in a particular way. Each legal form is also externally contradicted by other legal forms. When law negotiates a balance between the reproductive norms of responsibilities and rights, it demonstrates how particular legal forms manage the interaction of different sets of social relations, such as reproduction and exchange. PMID:15871155

  18. Automated Test-Form Generation

    ERIC Educational Resources Information Center

    van der Linden, Wim J.; Diao, Qi

    2011-01-01

    In automated test assembly (ATA), the methodology of mixed-integer programming is used to select test items from an item bank to meet the specifications for a desired test form and optimize its measurement accuracy. The same methodology can be used to automate the formatting of the set of selected items into the actual test form. Three different…

  19. When Permission Forms Work Best

    ERIC Educational Resources Information Center

    Zirkel, Perry A.

    2005-01-01

    Public schools routinely require permission or release forms for field trips and other activities of potential liability. The legal status of such forms varies, but they are generally considered neither rock-solid protection nor legally valueless in terms of immunity. This article presents a case involving a student who sustained bicycle injuries…

  20. Method of forming ceramic bricks

    DOEpatents

    Poeppel, R.B.; Claar, T.D.; Silkowski, P.

    1987-04-22

    A method for forming free standing ceramic bricks for use as tritium breeder material is disclosed. Aqueous solutions of sodium carbonate and potassium carbonate are mixed with an organic hydrocolloid dispersion and powdered lithium carbonate, spray dried, and ceramic bricks formed by molding in a die and firing.

  1. Method of forming ceramic bricks

    DOEpatents

    Poeppel, Roger B.; Claar, Terry D.; Silkowski, Peter

    1988-09-06

    A method for forming free standing ceramic bricks for use as tritium breeder material is disclosed. Aqueous solutions of sodium carbonate and potassium carbonate are mixed with an organic hydrocolloid dispersion and powdered lithium carbonate, spray dried, and ceramic bricks formed by molding in a die and firing.

  2. Method of forming ceramic bricks

    DOEpatents

    Poeppel, Roger B.; Claar, Terry D.; Silkowski, Peter

    1988-01-01

    A method for forming free standing ceramic bricks for use as tritium breeder material is disclosed. Aqueous solutions of sodium carbonate and potassium carbonate are mixed with an organic hydrocolloid dispersion and powdered lithium carbonate, spray dried, and ceramic bricks formed by molding in a die and firing.

  3. Quantum modular forms, mock modular forms, and partial theta functions

    NASA Astrophysics Data System (ADS)

    Kimport, Susanna

    Defined by Zagier in 2010, quantum modular forms have been the subject of an explosion of recent research. Many of these results are aimed at discovering examples of these functions, which are defined on the rational numbers and have "nice" modularity properties. Though the subject is in its early stages, numerous results (including Zagier's original examples) show these objects naturally arising from many areas of mathematics as limits of other modular-like functions. One such family of examples is due to Folsom, Ono, and Rhoades, who connected these new objects to partial theta functions (introduced by Rogers in 1917) and mock modular forms (about which there is a rich theory, whose origins date back to Ramanujan in 1920). In this thesis, we build off of the work of Folsom, Ono, and Rhoades by providing an infinite family of quantum modular forms of arbitrary positive half-integral weight. Further, this family of quantum modular forms "glues" mock modular forms to partial theta functions and is constructed from a so-called "universal" mock theta function by extending a method of Eichler and Zagier (originally defined for holomorphic Jacobi forms) into a non-holomorphic setting. In addition to the infinite family, we explore the weight 1/2 and 3/2 functions in more depth. For both of these weights, we are able to explicitly write down the quantum modular form, as well as the corresponding "errors to modularity," which can be shown to be Mordell integrals of specific theta functions and, as a consequence, are real-analytic functions. Finally, we turn our attention to the partial theta functions associated with these low weight examples. Berndt and Kim provide asymptotic expansions for a certain class of partial theta functions as q approaches 1 radially within the unit disk. Here, we extend this work to not only obtain asymptotic expansions for this class of functions as q approaches any root of unity, but also for a certain class of derivatives of these functions

  4. Process to form mesostructured films

    DOEpatents

    Brinker, C.J.; Anderson, M.T.; Ganguli, R.; Lu, Y.F.

    1999-01-12

    This invention comprises a method to form a family of supported films with pore size in the approximate range 0.8-20 nm exhibiting highly ordered microstructures and porosity derived from an ordered micellar or liquid-crystalline organic-inorganic precursor structure that forms during film deposition. Optically transparent, 100-500-nm thick films exhibiting a unique range of microstructures and uni-modal pore sizes are formed in seconds in a continuous coating operation. Applications of these films include sensors, membranes, low dielectric constant interlayers, anti-reflective coatings, and optical hosts. 12 figs.

  5. Process to form mesostructured films

    DOEpatents

    Brinker, C. Jeffrey; Anderson, Mark T.; Ganguli, Rahul; Lu, Yunfeng

    1999-01-01

    This invention comprises a method to form a family of supported films film with pore size in the approximate range 0.8-20 nm exhibiting highly ordered microstructures and porosity derived from an ordered micellar or liquid-crystalline organic-inorganic precursor structure that forms during film deposition. Optically transparent, 100-500-nm thick films exhibiting a unique range of microstructures and uni-modal pore sizes are formed in seconds in a continuous coating operation. Applications of these films include sensors, membranes, low dielectric constant interlayers, anti-reflective coatings, and optical hosts.

  6. Triggered pore-forming agents

    DOEpatents

    Bayley, Hagan; Walker, Barbara J.; Chang, Chung-yu; Niblack, Brett; Panchal, Rekha

    1998-01-01

    An inactive pore-forming agent which is activated to lytic function by a condition such as pH, light, heat, reducing potential, or metal ion concentration, or substance such as a protease, at the surface of a cell.

  7. Arbitrary p-form Galileons

    SciTech Connect

    Deffayet, C.; Deser, S.; Esposito-Farese, G.

    2010-09-15

    We show that scalar, 0-form, Galileon actions--models whose field equations contain only second derivatives--can be generalized to arbitrary even p-forms. More generally, they need not even depend on a single form, but may involve mixed p combinations, including equal p multiplets, where odd p fields are also permitted: We construct, for given dimension D, general actions depending on scalars, vectors, and higher p-form field strengths, whose field equations are of exactly second derivative order. We also discuss and illustrate their curved-space generalizations, especially the delicate nonminimal couplings required to maintain this order. Concrete examples of pure and mixed actions, field equations, and their curved-space extensions are presented.

  8. Differential form analysis using MACSYMA

    NASA Technical Reports Server (NTRS)

    Wahlquist, H. D.

    1977-01-01

    The MACSYMA file was written to perform these operations and discusses the improvements and additions which are needed to accomplish a complete and efficient implementation. Examples of differential form calculations are displayed.

  9. Process for forming planarized films

    DOEpatents

    Pang, Stella W.; Horn, Mark W.

    1991-01-01

    A planarization process and apparatus which employs plasma-enhanced chemical vapor deposition (PECVD) to form plarnarization films of dielectric or conductive carbonaceous material on step-like substrates.

  10. [Aspergillosis. Clinical forms and treatment].

    PubMed

    Fortún, Jesús; Meije, Yolanda; Fresco, Gema; Moreno, Santiago

    2012-04-01

    Invasive aspergillosis, chronic pulmonary aspergillosis and allergic bronchopulmonary aspergillosis are the clinical forms of aspergillosis. Although there is a great number of Aspergillus species, Aspergillus fumigatus-complex is the more frequent aetiological agent, regardless of clinical form or baseline condition. The increase in immunosuppressive agents and the higher use of corticosteroids in chronic obstructive pulmonary disease have led to aspergillosis becoming more prominent in recent years. Galactomannan detection and radiological diagnostic images complement the limitations of microbiology cultures in these patients. Voriconazole and liposomal amphotericin B are the gold standard in patients requiring therapy, and posaconazole, itraconazole, caspofungin and other echinocandins are effective alternatives. The prognosis depends of clinical forms and characteristics of the host, but it is particularly poor in the disseminated invasive forms.

  11. Confectionery-based dose forms.

    PubMed

    Tangso, Kristian J; Ho, Quy Phuong; Boyd, Ben J

    2015-01-01

    Conventional dosage forms such as tablets, capsules and syrups are prescribed in the normal course of practice. However, concerns about patient preferences and market demands have given rise to the exploration of novel unconventional dosage forms. Among these, confectionery-based dose forms have strong potential to overcome compliance problems. This report will review the availability of these unconventional dose forms used in treating the oral cavity and for systemic drug delivery, with a focus on medicated chewing gums, medicated lollipops, and oral bioadhesive devices. The aim is to stimulate increased interest in the opportunities for innovative new products that are available to formulators in this field, particularly for atypical patient populations. PMID:25146440

  12. Methods of forming hardened surfaces

    DOEpatents

    Branagan, Daniel J.

    2004-07-27

    The invention encompasses a method of forming a metallic coating. A metallic glass coating is formed over a metallic substrate. After formation of the coating, at least a portion of the metallic glass can be converted into a crystalline material having a nanocrystalline grain size. The invention also encompasses metallic coatings comprising metallic glass. Additionally, the invention encompasses metallic coatings comprising crystalline metallic material, with at least some of the crystalline metallic material having a nanocrystalline grain size.

  13. Method of forming pointed structures

    NASA Technical Reports Server (NTRS)

    Pugel, Diane E. (Inventor)

    2011-01-01

    A method of forming an array of pointed structures comprises depositing a ferrofluid on a substrate, applying a magnetic field to the ferrofluid to generate an array of surface protrusions, and solidifying the surface protrusions to form the array of pointed structures. The pointed structures may have a tip radius ranging from approximately 10 nm to approximately 25 micron. Solidifying the surface protrusions may be carried out at a temperature ranging from approximately 10 degrees C. to approximately 30 degrees C.

  14. Method for forming metal contacts

    DOEpatents

    Reddington, Erik; Sutter, Thomas C; Bu, Lujia; Cannon, Alexandra; Habas, Susan E; Curtis, Calvin J; Miedaner, Alexander; Ginley, David S; Van Hest, Marinus Franciscus Antonius Maria

    2013-09-17

    Methods of forming metal contacts with metal inks in the manufacture of photovoltaic devices are disclosed. The metal inks are selectively deposited on semiconductor coatings by inkjet and aerosol apparatus. The composite is heated to selective temperatures where the metal inks burn through the coating to form an electrical contact with the semiconductor. Metal layers are then deposited on the electrical contacts by light induced or light assisted plating.

  15. Superplastic forming of alloy 718

    SciTech Connect

    Smith, G.D.; Flower, H.L. )

    1994-04-01

    Inconel Alloy 718 (UNS N07718) is now available in a fine-grained, controlled composition modification that can be super-plastically formed. The new superplastic forming (SPF) capability allows the manufacture of large, complex, and detailed parts, which improves integrity by reducing the need for joining. Furthermore, it allows designers to fabricate components having higher strength, fatigue resistance, and temperature capability than parts made of aluminum or titanium alloys.

  16. INEL Spray-forming Research

    NASA Technical Reports Server (NTRS)

    Mchugh, Kevin M.; Key, James F.

    1993-01-01

    Spray forming is a near-net-shape fabrication technology in which a spray of finely atomized liquid droplets is deposited onto a suitably shaped substrate or mold to produce a coherent solid. The technology offers unique opportunities for simplifying materials processing without sacrificing, and oftentimes substantially improving, product quality. Spray forming can be performed with a wide range of metals and nonmetals, and offers property improvements resulting from rapid solidification (e.g., refined microstructures, extended solid solubilities and reduced segregation). Economic benefits result from process simplification and the elimination of unit operations. Researchers at the Idaho National Engineering Laboratory (INEL) are developing spray-forming technology for producing near-net-shape solids and coatings of a variety of metals, polymers, and composite materials. Results from several spray forming programs are presented to illustrate the range of capabilities of the technique as well as the accompanying technical and economic benefits. Low-carbon steel strip greater than 0.75 mm thick and polymer membranes for gas/gas and liquid/liquid separations that were spray formed are discussed; recent advances in spray forming molds, dies, and other tooling using low-melting-point metals are described.

  17. INEL spray-forming research

    SciTech Connect

    McHugh, K.M.; Key, J.F.

    1992-01-01

    Spray forming is a near-net-shape fabrication technology in which a spray of finely atomized liquid droplets is deposited onto a suitably shaped substrate or mold to produce a coherent solid. The technology offers unique opportunities for simplifying materials processing without sacrificing, and oftentimes substantially improving, product quality. Spray forming can be performed with a wide range of metals and nonmetals, and offers property improvements resulting from rapid solidification (e.g. refined microstructures, extended solid solubilities and reduced segregation). Economic benefits result from process simplification and the elimination of unit operations. Researchers at the Idaho National Engineering Laboratory (INEL) are developing spray-forming technology for producing near-net-shape solids and coatings of a variety of metals, polymers, and composite materials. Results from several spray-forming programs are presented to illustrate the range of capabilities of the technique as well as the accompanying technical and economic benefits. Low-carbon steel strip >0.75 mm thick and polymer membranes for gas/gas and liquid/liquid separations that were spray formed are discussed; recent advances in spray forming molds, dies, and other tooling using low-melting-point metals are described.

  18. INEL spray-forming research

    SciTech Connect

    McHugh, K.M.; Key, J.F.

    1992-12-31

    Spray forming is a near-net-shape fabrication technology in which a spray of finely atomized liquid droplets is deposited onto a suitably shaped substrate or mold to produce a coherent solid. The technology offers unique opportunities for simplifying materials processing without sacrificing, and oftentimes substantially improving, product quality. Spray forming can be performed with a wide range of metals and nonmetals, and offers property improvements resulting from rapid solidification (e.g. refined microstructures, extended solid solubilities and reduced segregation). Economic benefits result from process simplification and the elimination of unit operations. Researchers at the Idaho National Engineering Laboratory (INEL) are developing spray-forming technology for producing near-net-shape solids and coatings of a variety of metals, polymers, and composite materials. Results from several spray-forming programs are presented to illustrate the range of capabilities of the technique as well as the accompanying technical and economic benefits. Low-carbon steel strip >0.75 mm thick and polymer membranes for gas/gas and liquid/liquid separations that were spray formed are discussed; recent advances in spray forming molds, dies, and other tooling using low-melting-point metals are described.

  19. Superplastic forming of ceramic insulation

    NASA Technical Reports Server (NTRS)

    Nieh, T. G.; Wittenauer, J. P.; Wadsworth, J.

    1992-01-01

    Superplasticity has been demonstrated in many fine-grained structural ceramics and ceramic composites, including yttria-stabilized tetragonal zirconia polycrystal (YTZP), alumina, and Al2O3-reinforced zirconia (Al2O3/YTZ) duplex composites and SiC-reinforced Si3N4. These superplastic ceramics obviously offer the potential benefit of forming net shape or near net shape parts. This could be particularly useful for forming complicated shapes that are difficult to achieve using conventional forming techniques, or require elaborate, subsequent machining. In the present study, we successfully demonstrated the following: (1) superplastic 3Y-TXP and 20 percent Al2O3/YTZ composite have for the first time been successfully deformed into hemispherical caps via a biaxial gas-pressure forming technique; (2) no experimental difficulty was encountered in applying the required gas pressures and temperatures to achieve the results, thus, it is certain that higher rates of deformation than those presented in this study will be possible by using the current test apparatus at higher temperatures and pressures; and (3) an analytical model incorporating material parameters, such as variations during forming in the strain rate sensitivity exponent and grain growth-induced strain hardening, is needed to model accurately and therefore precisely control the biaxial gas-pressure forming of superplastic ceramics. Based on the results of this study, we propose to fabricate zirconia insulation tubes by superplastic extrusion of zirconia polycrystal. This would not only reduce the cost, but also improve the reliability of the tube products.

  20. Characterization of polymorphic ampicillin forms.

    PubMed

    Baraldi, C; Tinti, A; Ottani, S; Gamberini, M C

    2014-11-01

    In this work polymorphs of α-aminobenzylpenicillin (ampicillin), a β-lactamic antibiotic, were prepared and investigated by several experimental and theoretical methods. Amorphous monohydrate and three crystalline forms, the trihydrate, the crystal form I and the crystal form II, were investigated by FT-IR and micro-Raman. Also data obtained by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray powder diffraction (XRPD) and hot-stage Raman spectroscopy are reported. Finally, quantum mechanical calculations were performed by density functional theory (DFT) to assist the assignment of spectroscopic experimental bands. For the first time, the ampicillin molecule in its zwitterionic form was studied at the B3LYP/aug-cc-pVDZ level and the corresponding theoretical vibrational spectra were computed. In fact, ampicillin in the crystal is in zwitterionic form and concentrations of this same form are quite relevant in solutions at physiological pH. Experimental and theoretical results allowed identification of specific features for polymorph characterization. Bands typical of the different polymorphs are identified both in IR and Raman spectra: in particular in the NH stretching region (IR), in the amide I+δNH region (both techniques), in the 1520-1490cm(-1) region (IR), in the 1320-1300cm(-1) and 1280-1220cm(-1) (IR), in the 1200-1170cm(-1) (Raman), in the amide V region (IR), and, finally, in the 715-640cm(-1) and 220-200cm(-1) (Raman). Interconversion among different polymorphs was investigated by hot-stage Raman spectroscopy and thermal analysis, clarifying the complex pattern of transformations undergone as a function of temperature and heating rate. In particular, DSC scans show how the trihydrate crystals transform into anhydrous forms on heating. Finally, stability tests demonstrated, after a two years period, that no transformation or degradation of the polymorphs occurred.

  1. The discovery of structural form

    PubMed Central

    Kemp, Charles; Tenenbaum, Joshua B.

    2008-01-01

    Algorithms for finding structure in data have become increasingly important both as tools for scientific data analysis and as models of human learning, yet they suffer from a critical limitation. Scientists discover qualitatively new forms of structure in observed data: For instance, Linnaeus recognized the hierarchical organization of biological species, and Mendeleev recognized the periodic structure of the chemical elements. Analogous insights play a pivotal role in cognitive development: Children discover that object category labels can be organized into hierarchies, friendship networks are organized into cliques, and comparative relations (e.g., “bigger than” or “better than”) respect a transitive order. Standard algorithms, however, can only learn structures of a single form that must be specified in advance: For instance, algorithms for hierarchical clustering create tree structures, whereas algorithms for dimensionality-reduction create low-dimensional spaces. Here, we present a computational model that learns structures of many different forms and that discovers which form is best for a given dataset. The model makes probabilistic inferences over a space of graph grammars representing trees, linear orders, multidimensional spaces, rings, dominance hierarchies, cliques, and other forms and successfully discovers the underlying structure of a variety of physical, biological, and social domains. Our approach brings structure learning methods closer to human abilities and may lead to a deeper computational understanding of cognitive development. PMID:18669663

  2. The discovery of structural form.

    PubMed

    Kemp, Charles; Tenenbaum, Joshua B

    2008-08-01

    Algorithms for finding structure in data have become increasingly important both as tools for scientific data analysis and as models of human learning, yet they suffer from a critical limitation. Scientists discover qualitatively new forms of structure in observed data: For instance, Linnaeus recognized the hierarchical organization of biological species, and Mendeleev recognized the periodic structure of the chemical elements. Analogous insights play a pivotal role in cognitive development: Children discover that object category labels can be organized into hierarchies, friendship networks are organized into cliques, and comparative relations (e.g., "bigger than" or "better than") respect a transitive order. Standard algorithms, however, can only learn structures of a single form that must be specified in advance: For instance, algorithms for hierarchical clustering create tree structures, whereas algorithms for dimensionality-reduction create low-dimensional spaces. Here, we present a computational model that learns structures of many different forms and that discovers which form is best for a given dataset. The model makes probabilistic inferences over a space of graph grammars representing trees, linear orders, multidimensional spaces, rings, dominance hierarchies, cliques, and other forms and successfully discovers the underlying structure of a variety of physical, biological, and social domains. Our approach brings structure learning methods closer to human abilities and may lead to a deeper computational understanding of cognitive development.

  3. Form und Sinn: Sprachwissenschaftliche Betrachtungen (Form and Meaning: Linguistic Observations).

    ERIC Educational Resources Information Center

    Jakobson, Roman

    This collection of 14 papers and articles by Roman Jakobson contains works written and published between 1931 and 1970 which deal either with global aspects of language or with specific grammatical issues. The collection emphasizes Jakobson's concern for finding the links between form and meaning in language. The text is entirely in German with…

  4. Acceptance of Ideas of Others [Number Form and Star Form].

    ERIC Educational Resources Information Center

    Masters, James R.; Laverty, Grace E.

    As part of the instrumentation to assess the effectiveness of the Schools Without Failure (SWF) program in 10 elementary schools in the New Castle, Pa. School District, the Acceptance of Ideas of Others (Number and Star Forms) were developed to determine pupils' attitudes toward classmates. Given a list of all class members, pupils are asked to…

  5. Sixth-Form Colleges: An Endangered Organisational Form?

    ERIC Educational Resources Information Center

    Stoten, David William

    2014-01-01

    The sixth-form college sector is often marginalised in policy and academic discourse, where the much larger school and further education sectors dominate. This paper sets out to describe the sector's key features, assess its position within the wider education system and consider its future in an increasingly competitive education market. The…

  6. Substrate system for spray forming

    DOEpatents

    Chu, Men G.; Chernicoff, William P.

    2002-01-01

    A substrate system for receiving a deposit of sprayed metal droplets including a movable outer substrate on which the sprayed metal droplets are deposited. The substrate system also includes an inner substrate disposed adjacent the outer substrate where the sprayed metal droplets are deposited on the outer substrate. The inner substrate includes zones of differing thermal conductivity to resist substrate layer porosity and to resist formation of large grains and coarse constituent particles in a bulk layer of the metal droplets which have accumulated on the outer substrate. A spray forming apparatus and associated method of spray forming a molten metal to form a metal product using the substrate system of the invention is also provided.

  7. Substrate system for spray forming

    DOEpatents

    Chu, Men G.; Chernicoff, William P.

    2000-01-01

    A substrate system for receiving a deposit of sprayed metal droplets including a movable outer substrate on which the sprayed metal droplets are deposited. The substrate system also includes an inner substrate disposed adjacent the outer substrate where the sprayed metal droplets are deposited on the outer substrate. The inner substrate includes zones of differing thermal conductivity to resist substrate layer porosity and to resist formation of large grains and coarse constituent particles in a bulk layer of the metal droplets which have accumulated on the outer substrate. A spray forming apparatus and associated method of spray forming a molten metal to form a metal product using the substrate system of the invention is also provided.

  8. PROCESS OF FORMING POWDERED MATERIAL

    DOEpatents

    Glatter, J.; Schaner, B.E.

    1961-07-14

    A process of forming high-density compacts of a powdered ceramic material is described by agglomerating the powdered ceramic material with a heat- decompossble binder, adding a heat-decompossble lubricant to the agglomerated material, placing a quantity of the material into a die cavity, pressing the material to form a compact, pretreating the compacts in a nonoxidizing atmosphere to remove the binder and lubricant, and sintering the compacts. When this process is used for making nuclear reactor fuel elements, the ceramic material is an oxide powder of a fissionsble material and after forming, the compacts are placed in a cladding tube which is closed at its ends by vapor tight end caps, so that the sintered compacts are held in close contact with each other and with the interior wall of the cladding tube.

  9. Methods of forming boron nitride

    DOEpatents

    Trowbridge, Tammy L; Wertsching, Alan K; Pinhero, Patrick J; Crandall, David L

    2015-03-03

    A method of forming a boron nitride. The method comprises contacting a metal article with a monomeric boron-nitrogen compound and converting the monomeric boron-nitrogen compound to a boron nitride. The boron nitride is formed on the same or a different metal article. The monomeric boron-nitrogen compound is borazine, cycloborazane, trimethylcycloborazane, polyborazylene, B-vinylborazine, poly(B-vinylborazine), or combinations thereof. The monomeric boron-nitrogen compound is polymerized to form the boron nitride by exposure to a temperature greater than approximately 100.degree. C. The boron nitride is amorphous boron nitride, hexagonal boron nitride, rhombohedral boron nitride, turbostratic boron nitride, wurzite boron nitride, combinations thereof, or boron nitride and carbon. A method of conditioning a ballistic weapon and a metal article coated with the monomeric boron-nitrogen compound are also disclosed.

  10. Method of forming structural heliostat

    DOEpatents

    Anderson, Alfred J.

    1984-06-26

    In forming a heliostat having a main support structure and pivoting and tilting motors and gears and a mirror module for reflecting solar energy onto a collector, the improvement characterized by a method of forming the mirror module in which the mirror is laid upon a solid rigid supporting bed in one or more sections, with or without focusing; a mirror backing sheet is applied by first applying respective thin layers of silicone grease and, thereafter, progressively rolling application to eliminate air bubbles; followed by affixing of a substrate assembly to the mirror backing sheet to form a mirror module that does not curve because of thermally induced stresses and differential thermal expansion or contraction effects. The silicone grease also serves to dampen fluttering of the mirror and protect the mirror backside against adverse effects of the weather. Also disclosed are specific details of preferred embodiments.

  11. Auxin biosynthesis and storage forms

    PubMed Central

    Strader, Lucia C.

    2013-01-01

    The plant hormone auxin drives plant growth and morphogenesis. The levels and distribution of the active auxin indole-3-acetic acid (IAA) are tightly controlled through synthesis, inactivation, and transport. Many auxin precursors and modified auxin forms, used to regulate auxin homeostasis, have been identified; however, very little is known about the integration of multiple auxin biosynthesis and inactivation pathways. This review discusses the many ways auxin levels are regulated through biosynthesis, storage forms, and inactivation, and the potential roles modified auxins play in regulating the bioactive pool of auxin to affect plant growth and development. PMID:23580748

  12. FORM version 4.0

    NASA Astrophysics Data System (ADS)

    Kuipers, J.; Ueda, T.; Vermaseren, J. A. M.; Vollinga, J.

    2013-05-01

    We present version 4.0 of the symbolic manipulation system FORM. The most important new features are manipulation of rational polynomials and the factorization of expressions. Many other new functions and commands are also added; some of them are very general, while others are designed for building specific high level packages, such as one for Gröbner bases. New is also the checkpoint facility, that allows for periodic backups during long calculations. Finally, FORM 4.0 has become available as open source under the GNU General Public License version 3. Program summaryProgram title: FORM. Catalogue identifier: AEOT_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEOT_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU General Public License, version 3 No. of lines in distributed program, including test data, etc.: 151599 No. of bytes in distributed program, including test data, etc.: 1 078 748 Distribution format: tar.gz Programming language: The FORM language. FORM itself is programmed in a mixture of C and C++. Computer: All. Operating system: UNIX, LINUX, Mac OS, Windows. Classification: 5. Nature of problem: FORM defines a symbolic manipulation language in which the emphasis lies on fast processing of very large formulas. It has been used successfully for many calculations in Quantum Field Theory and mathematics. In speed and size of formulas that can be handled it outperforms other systems typically by an order of magnitude. Special in this version: The version 4.0 contains many new features. Most important are factorization and rational arithmetic. The program has also become open source under the GPL. The code in CPC is for reference. You are encouraged to upload the most recent sources from www.nikhef.nl/form/formcvs.php because of frequent bug fixes. Solution method: See "Nature of Problem", above. Additional comments: NOTE: The code in CPC is for reference. You are encouraged

  13. Auxin biosynthesis and storage forms.

    PubMed

    Korasick, David A; Enders, Tara A; Strader, Lucia C

    2013-06-01

    The plant hormone auxin drives plant growth and morphogenesis. The levels and distribution of the active auxin indole-3-acetic acid (IAA) are tightly controlled through synthesis, inactivation, and transport. Many auxin precursors and modified auxin forms, used to regulate auxin homeostasis, have been identified; however, very little is known about the integration of multiple auxin biosynthesis and inactivation pathways. This review discusses the many ways auxin levels are regulated through biosynthesis, storage forms, and inactivation, and the potential roles modified auxins play in regulating the bioactive pool of auxin to affect plant growth and development.

  14. 48 CFR Appendix - List of IAAR Forms

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 6 2012-10-01 2012-10-01 false List of IAAR Forms Federal Acquisition Regulations System BROADCASTING BOARD OF GOVERNORS CLAUSES AND FORMS FORMS Illustrations of Forms The Broadcasting Board of Governors forms. List of IAAR Forms 1953.370-21The Broadcasting Board of Governors Form IA-21, Abstract...

  15. 48 CFR Appendix - List of IAAR Forms

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Acquisition Regulations System BROADCASTING BOARD OF GOVERNORS CLAUSES AND FORMS FORMS Illustrations of Forms The Broadcasting Board of Governors forms. List of IAAR Forms 1953.370-21The Broadcasting Board of Governors Form IA-21, Abstract of Quotations. 1953.370-44The Broadcasting Board of Governors Form...

  16. 48 CFR 53.301 - Standard forms.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Standard forms. 53.301... AND FORMS FORMS Illustrations of Forms 53.301 Standard forms. This section illustrates the standard... order. The subsection numbers correspond with the standard form numbers (e.g., Standard Form 18...

  17. 48 CFR Appendix - List of IAAR Forms

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true List of IAAR Forms Federal Acquisition Regulations System BROADCASTING BOARD OF GOVERNORS CLAUSES AND FORMS FORMS Illustrations of Forms The Broadcasting Board of Governors forms. List of IAAR Forms 1953.370-21The Broadcasting Board of Governors Form IA-21, Abstract...

  18. 48 CFR Appendix - List of IAAR Forms

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 6 2011-10-01 2011-10-01 false List of IAAR Forms Federal Acquisition Regulations System BROADCASTING BOARD OF GOVERNORS CLAUSES AND FORMS FORMS Illustrations of Forms The Broadcasting Board of Governors forms. List of IAAR Forms 1953.370-21The Broadcasting Board of Governors Form IA-21, Abstract...

  19. Triggered pore-forming agents

    DOEpatents

    Bayley, H.; Walker, B.J.; Chang, C.Y.; Niblack, B.; Panchal, R.

    1998-07-07

    An inactive pore-forming agent is revealed which is activated to lytic function by a condition such as pH, light, heat, reducing potential, or metal ion concentration, or substance such as a protease, at the surface of a cell. 30 figs.

  20. Technetium Immobilization Forms Literature Survey

    SciTech Connect

    Westsik, Joseph H.; Cantrell, Kirk J.; Serne, R. Jeffrey; Qafoku, Nikolla

    2014-05-01

    Of the many radionuclides and contaminants in the tank wastes stored at the Hanford site, technetium-99 (99Tc) is one of the most challenging to effectively immobilize in a waste form for ultimate disposal. Within the Hanford Tank Waste Treatment and Immobilization Plant (WTP), the Tc will partition between both the high-level waste (HLW) and low-activity waste (LAW) fractions of the tank waste. The HLW fraction will be converted to a glass waste form in the HLW vitrification facility and the LAW fraction will be converted to another glass waste form in the LAW vitrification facility. In both vitrification facilities, the Tc is incorporated into the glass waste form but a significant fraction of the Tc volatilizes at the high glass-melting temperatures and is captured in the off-gas treatment systems at both facilities. The aqueous off-gas condensate solution containing the volatilized Tc is recycled and is added to the LAW glass melter feed. This recycle process is effective in increasing the loading of Tc in the LAW glass but it also disproportionally increases the sulfur and halides in the LAW melter feed which increases both the amount of LAW glass and either the duration of the LAW vitrification mission or the required supplemental LAW treatment capacity.

  1. How Public Opinion is Formed

    ERIC Educational Resources Information Center

    Block, Edward M.

    1977-01-01

    Investigates the evolution of the definition of public relations by examining cultural and personal determinants of public opinion. Outlines functions of communicators and opinionmakers in forming and influencing public opinion. Available from: Public Relations Review, Ray Hiebert, Dean, College of Journalism, University of Maryland, College Park,…

  2. Acceptance of Others (Number Form).

    ERIC Educational Resources Information Center

    Masters, James R.; Laverty, Grace E.

    As part of the instrumentation to assess the effectiveness of the Schools Without Failure (SWF) program in 10 elementary schools in the New Castle, Pa. School District, the Acceptance of Others (Number Form) was prepared to determine pupil's attitudes toward classmates. Given a list of all class members, pupils are asked to circle a number from 1…

  3. Collaborating with Forms in Nature

    ERIC Educational Resources Information Center

    Castro, Aileen Pugliese

    2011-01-01

    Taking students outside is a great opportunity to make art. In this article, the author describes how her students collaborated with forms in nature to create their own visual structures to communicate ideas. This lesson can be done on the beach, in a sand box on the school playground, in grassy areas, or nature can even be brought into the…

  4. Process for forming sulfuric acid

    DOEpatents

    Lu, Wen-Tong P.

    1981-01-01

    An improved electrode is disclosed for the anode in a sulfur cycle hydrogen generation process where sulfur dioxie is oxidized to form sulfuric acid at the anode. The active compound in the electrode is palladium, palladium oxide, an alloy of palladium, or a mixture thereof. The active compound may be deposited on a porous, stable, conductive substrate.

  5. English Pidgins: Form and Function.

    ERIC Educational Resources Information Center

    Mufwene, Salikoko S.

    1988-01-01

    Highlights similarities and variation in both form and function of English pidgins the world over. It is argued that English pidgins are related more by socio-historical conditions and directions of development than by details of their formal structure. Reference list includes 68 citations. (Author/DJD)

  6. PIC Reading Readiness Test Form.

    ERIC Educational Resources Information Center

    Short, N. J.

    This rating form concerns the measurement of basic skills in connection with assessing reading readiness. Motor skills, ability to adjust to learning situations, familiarity with the alphabet, and general knowledge are assessed. See TM 001 111 for details of the Regional PIC program in which it is used. (DLG)

  7. Spin-forming Project Report

    SciTech Connect

    Switzner, Nathan; Henry, Dick

    2009-03-20

    In a second development order, spin-forming equipment was again evaluated using the test shape, a hemispherical shell. In this second development order, pure vanadium and alloy titanium (Ti-6Al-4V) were spin-formed, as well as additional copper and 21-6-9 stainless. In the first development order the following materials had been spin-formed: copper (alloy C11000 ETP), 6061 aluminum, 304L stainless steel, 21-6-9 stainless steel, and tantalum-2.5% tungsten. Significant challenges included properly adjusting the rotations-per-minute (RPM), cracking at un-beveled edges and laser marks, redressing of notches, surface cracking, non-uniform temperature evolution in the titanium, and cracking of the tailstock. Lessons learned were that 300 RPM worked better than 600 RPM for most materials (at the feed rate of 800 mm/min); beveling the edges to lower the stress reduces edge cracking; notches, laser marks, or edge defects in the preform doom the process to cracking and failure; coolant is required for vanadium spin-forming; increasing the number of passes to nine or more eliminates surface cracking for vanadium; titanium develops a hot zone in front of the rollers; and the tailstock should be redesigned to eliminate the cylindrical stress concentrator in the center.

  8. Assessing "Combining Forms" in Science.

    ERIC Educational Resources Information Center

    Floriani, Bernard P.; Cairns, Jack C.

    1982-01-01

    Since there appears to be a direct relationship between reading comprehension and vocabulary, an inventory is offered which assesses students' knowledge of the meaning of "combining forms" (automobile, aero-dynamics, etc.) and not words themselves. The inventory can serve as a model to develop additional inventories for Latin/Greek roots.…

  9. Thermolysin: a peptide forming enzyme.

    PubMed

    Reddy, A V

    1991-02-01

    Thermolysin, a thermostable endopeptidase, is recognised as a potential peptide bond forming enzyme. The importance of structural properties and its stereospecific nature towards peptide bond formation is described. Thermolysin's use in the keystep of the preparation of an artificial sweetener 'aspartame' is highlighted.

  10. Polynomial Algebra in Form 4

    NASA Astrophysics Data System (ADS)

    Kuipers, J.

    2012-06-01

    New features of the symbolic algebra package Form 4 are discussed. Most importantly, these features include polynomial factorization and polynomial gcd computation. Examples of their use are shown. One of them is an exact version of Mincer which gives answers in terms of rational polynomials and 5 master integrals.

  11. Anatomical form defines color: function, form, and aesthetics.

    PubMed

    Terry, Douglas A; Geller, Willi; Tric, Olivier; Anderson, Mark J; Tourville, Monte; Kobashigawa, Alvin

    2002-01-01

    Contemporary composite materials enable the reproduction of polychromatic effects within a tooth. A broader definition of color that incorporates the anatomy and optical properties of a tooth must be developed so the dental professional can better understand the infinite possibilities of color that exist within the tooth and restoration. This article describes a direct protocol for the development of natural restorations in the posterior dentition through the integration of function, form, and color.

  12. Electro-Hydraulic Forming of Sheet Metals: Free-forming vs. Conical-die Forming

    SciTech Connect

    Rohatgi, Aashish; Stephens, Elizabeth V.; Davies, Richard W.; Smith, Mark T.; Soulami, Ayoub; Ahzi, Said

    2012-05-01

    This work builds upon our recent advances in quantifying high-rate deformation behavior of sheet metals, during electro-hydraulic forming (EHF), using high-speed imaging and digital image correlation techniques. Following recent publication of an earlier manuscript, resulting from this project, in the Journal of Materials Processing Technology, this manuscript further details our results and compares forming behavior when the process is carried out inside an open-die or a conical die. It is anticipated that quantitative information of the sheet deformation history, made possible by the experimental technique developed in this work, will improve our understanding on the roles of strain-rate and sheet-die interactions in enhancing the sheet metal formability during high-rate forming. This knowledge will be beneficial to the automotive industry and enable them to fabricate light-weight sheet parts out of Al and advanced high strength steels.

  13. 76 FR 61725 - Agency Information Collection Activities: Case Submission Form, Case Assistance Form; (Form DHS...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-05

    ... Federal Register on July 18, 2011 at 76 FR 42129, for a 60-day public comment period. No comments were... other forms of information technology, e.g., permitting electronic submissions of responses. FOR FURTHER... to bring to the attention of the CIS Ombudsman (``trend''). For case problems, the CIS Ombudsman...

  14. Method of forming a joint

    DOEpatents

    Butt, Darryl Paul; Cutler, Raymond Ashton; Rynders, Steven Walton; Carolan, Michael Francis

    2006-08-22

    A method of joining at least two sintered bodies to form a composite structure, including providing a first multicomponent metallic oxide having a perovskitic or fluorite crystal structure; providing a second sintered body including a second multicomponent metallic oxide having a crystal structure of the same type as the first; and providing at an interface a joint material containing at least one metal oxide containing at least one metal identically contained in at least one of the first and second multicomponent metallic oxides. The joint material is free of cations of Si, Ge, Sn, Pb, P and Te and has a melting point below the sintering temperatures of both sintered bodies. The joint material is heated to a temperature above the melting point of the metal oxide(s) and below the sintering temperatures of the sintered bodies to form the joint. Structures containing such joints are also disclosed.

  15. Free-form illumination optics

    NASA Astrophysics Data System (ADS)

    Mohedano, Rubén; Chaves, Julio; Hernández, Maikel

    2016-04-01

    In many illumination problems, the beam pattern needed and/or some geometrical constraints lead to very asymmetric design conditions. These asymmetries have been solved in the past by means of arrangements of rotationally symmetric or linear lamps aimed in different directions whose patterns overlap to provide the asymmetric prescriptions or by splitting one single lamp into several sections, each one providing a part of the pattern. The development of new design methods yielding smooth continuous free-form optical surfaces to solve these challenging design problems, combined with the proper CAD modeling tools plus the development of multiple axes diamond turn machines, give birth to a new generation of optics. These are able to offer the performance and other advanced features, such as efficiency, compactness, or aesthetical advantages, and can be manufactured at low cost by injection molding. This paper presents two examples of devices with free-form optical surfaces, a camera flash, and a car headlamp.

  16. Cyclodextrin Inclusion Polymers Forming Hydrogels

    NASA Astrophysics Data System (ADS)

    Li, Jun

    This chapter reviews the advances in the developments of supramolecular hydrogels based on the polypseudorotaxanes and polyrotaxanes formed by inclusion complexes of cyclodextrins threading onto polymer chains. Both physical and chemical supramolecular hydrogels of many different types are discussed with respect to their preparation, structure, property, and gelation mechanism. A large number of physical supramolecular hydrogels were formed induced by self-assembly of densely packed cyclodextrin rings threaded on polymer or copolymer chains acting as physical crosslinking points. The thermo-reversible and thixotropic properties of these physical supramolecular hydrogels have inspired their applications as injectable drug delivery systems. Chemical supramolecular hydrogels synthesized from polypseudorotaxanes and polyrotaxanes were based on the chemical crosslinking of either the cyclodextrin molecules or the included polymer chains. The chemical supramolecular hydrogels were often made biodegradable through incorporation of hydrolyzable threading polymers, end caps, or crosslinkers, for their potential applications as biomaterials.

  17. Sphere forming method and apparatus

    NASA Technical Reports Server (NTRS)

    Youngberg, C. L.; Miller, C. G.; Stephens, J. B.; Finnerty, A. A. (Inventor)

    1983-01-01

    A system is provided for forming small accurately spherical objects. Preformed largely spherical objects are supported at the opening of a conduit on the update of hot gas emitted from the opening, so the object is in a molten state. The conduit is suddenly jerked away at a downward incline, to allow the molten object to drop in free fall, so that surface tension forms a precise sphere. The conduit portion that has the opening, lies in a moderate vacuum chamber, and the falling sphere passes through the chamber and through a briefly opened valve into a tall drop tower that contains a lower pressure, to allow the sphere to cool without deformation caused by falling through air.

  18. Unsplit bipolar pulse forming line

    DOEpatents

    Rhodes, Mark A.

    2011-05-24

    A bipolar pulse forming transmission line module and system for linear induction accelerators having first, second, third, and fourth planar conductors which form a sequentially arranged interleaved stack having opposing first and second ends, with dielectric layers between the conductors. The first and second planar conductors are connected to each other at the first end, and the first and fourth planar conductors are connected to each other at the second end via a shorting plate. The third planar conductor is electrically connectable to a high voltage source, and an internal switch functions to short at the first end a high voltage from the third planar conductor to the fourth planar conductor to produce a bipolar pulse at the acceleration axis with a zero net time integral. Improved access to the switch is enabled by an aperture through the shorting plate and the proximity of the aperture to the switch.

  19. Method for forming hermetic seals

    NASA Technical Reports Server (NTRS)

    Gallagher, Brian D.

    1987-01-01

    The firmly adherent film of bondable metal, such as silver, is applied to the surface of glass or other substrate by decomposing a layer of solution of a thermally decomposable metallo-organic deposition (MOD) compound such as silver neodecanoate in xylene. The MOD compound thermally decomposes into metal and gaseous by-products. Sealing is accomplished by depositing a layer of bonding metal, such as solder or a brazing alloy, on the metal film and then forming an assembly with another high melting point metal surface such as a layer of Kovar. When the assembly is heated above the temperature of the solder, the solder flows, wets the adjacent surfaces and forms a hermetic seal between the metal film and metal surface when the assembly cools.

  20. Method of forming calthrate ice

    DOEpatents

    Hino, T.; Gorski, A.J.

    1985-09-30

    A method of forming clathrate ice in a supercooled water-based liquid contained in a vessel is disclosed. Initially, an oscillator device is located in the liquid in the vessel. The oscillator device is then oscillated ultransonically so that small crystals are formed in the liquid. Thes small crystals serve as seed crystals for ice formation in the liquid and thereby prevent supercooling of the liquid. Preferably, the oscillating device is controlled by a thermostat which initiates operation of the oscillator device when the temperature of the liquid is lowered to the freezing point. Thereafter, the operation of the oscillator device is terminated when ice is sensed in the liquid by an ice sensor.

  1. Method of forming clathrate ice

    DOEpatents

    Hino, Toshiyuki; Gorski, Anthony J.

    1987-01-01

    A method of forming clathrate ice in a supercooled water-based liquid contained in a vessel is disclosed. Initially, an oscillator device is located in the liquid in the vessel. The oscillator device is then oscillated ultrasonically so that small crystals are formed in the liquid. These small crystals serve as seed crystals for ice formation in the liquid and thereby prevent supercooling of the liquid. Preferably, the oscillating device is controlled by a thermostat which initiates operation of the oscillator device when the temperature of the liquid is lowered to the freezing point. Thereafter, the operation of the oscillator device is terminated when ice is sensed in the liquid by an ice sensor.

  2. Rheology of hydrate forming emulsions.

    PubMed

    Peixinho, Jorge; Karanjkar, Prasad U; Lee, Jae W; Morris, Jeffrey F

    2010-07-20

    Results are reported on an experimental study of the rheology of hydrate-forming water-in-oil emulsions. Density-matched concentrated emulsions were quenched by reducing the temperature and an irreversible transition was observed where the viscosity increased dramatically. The hydrate-forming emulsions have characteristic times for abrupt viscosity change dependent only on the temperature, reflecting the importance of the effect of subcooling. Mechanical transition of hydrate-free water-in-oil emulsions may require longer times and depends on the shear rate, occurring more rapidly at higher rates but with significant scatter which is characterized through a probabilistic analysis. This rate dependence together with dependence on subcooling reflects the importance of hydrodynamic forces to bring drops or particles together.

  3. Studying how protein crystals form

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Watching molecules of the iron-storing protein apoferritin come together to form a nucleus reveals some interesting behavior. In this series of images, researchers observed clusters of four molecules at the corners of a diamond shape (top). As more molecules attach to the cluster, they arrange themselves into rods (second from top), and a raft-like configuration of molecules forms the critical nucleus (third from top), suggesting that crystal growth is much slower than it could be were the molecules arranged in a more compact formation. In the final image, a crystallite consisting of three layers containing approximately 60 to 70 molecules each is formed. Atomic force microscopy made visualizing the process of nucleation possible for the first time. The principal investigator is Peter Vekilov, of the University of Alabama in Huntsville. Vekilov's team at UAH studies protein solutions as they change phases from liquids to crystalline solids. They want to know if the molecules in the solution interact with one another, and if so, how, from the perspectives of thermodynamics and kinetics. They want to understand which forces -- electrical, electrostatic, hydrodynamic, or other kinds of forces -- are responsible for the interactions. They also study nucleation, the begirning stage of crystallization. This process is important to understand because it sets the stage for crystal growth in all kinds of solutions and liquid melts that are important in such diverse fields as agriculture, medicine, and the fabrication of metal components. Nucleation can determine the rate of crystal growth, the number of crystals that will be formed, and the quality and size of the crystals.

  4. How do atmospheric rivers form?

    NASA Astrophysics Data System (ADS)

    Dacre, Helen

    2015-04-01

    The term atmospheric river is used to describe corridors of strong water vapor transport in the troposphere. Filaments of enhanced water vapor, commonly observed in satellite imagery extending from the subtropics to the extratropics, are routinely used as a proxy for identifying these regions of strong water vapor transport. The precipitation associated with these filaments of enhanced water vapor can lead to high impact flooding events. However, there remains some debate as to how these filaments form. In this study we analyse the transport of water vapor within a climatology of wintertime North Atlantic extratropical cyclones. Results show that atmospheric rivers are formed by the cold front which sweeps up water vapor in the warm sector as it catches up with the warm front. This causes a narrow band of high water vapor content to form ahead of the cold front at the base of the warm conveyor belt airflow. Thus, water vapor in the cyclone's warm sector, and not long-distance transport of water vapor from the subtropics, is responsible for the generation of filaments of high water vapor content. A continuous cycle of evaporation and moisture convergence within the cyclone replenishes water vapor lost via precipitation. Thus, rather than representing a direct and continuous feed of moist air from the subtropics into the centre of a cyclone (as suggested by the term atmospheric river), these filaments are, in-fact, the result of water vapor exported from the cyclone and thus they represent the footprints left behind as cyclones travel polewards from subtropics.

  5. Coated particle waste form development

    SciTech Connect

    Oma, K.H.; Buckwalter, C.Q.; Chick, L.A.

    1981-12-01

    Coated particle waste forms have been developed as part of the multibarrier concept at Pacific Northwest Laboratory under the Alternative Waste Forms Program for the Department of Energy. Primary efforts were to coat simulated nuclear waste glass marbles and ceramic pellets with low-temperature pyrolytic carbon (LT-PyC) coatings via the process of chemical vapor deposition (CVD). Fluidized bed (FB) coaters, screw agitated coaters (SAC), and rotating tube coaters were used. Coating temperatures were reduced by using catalysts and plasma activation. In general, the LT-PyC coatings did not provide the expected high leach resistance as previously measured for carbon alone. The coatings were friable and often spalled off the substrate. A totally different concept, thermal spray coating, was investigated at PNL as an alternative to CVD coating. Flame spray, wire gun, and plasma gun systems were evaluated using glass, ceramic, and metallic coating materials. Metal plasma spray coatings (Al, Sn, Zn, Pb) provided a two to three orders-of-magnitude increase in chemical durability. Because the aluminum coatings were porous, the superior leach resistance must be due to either a chemical interaction or to a pH buffer effect. Because they are complex, coated waste form processes rank low in process feasibility. Of all the possible coated particle processes, plasma sprayed marbles have the best rating. Carbon coating of pellets by CVD ranked ninth when compared with ten other processes. The plasma-spray-coated marble process ranked sixth out of eleven processes.

  6. Rib forming tool for tubing

    DOEpatents

    Rowley, James P.; Lewandowski, Edward F.; Groh, Edward F.

    1976-01-01

    Three cylindrical rollers are rotatably mounted equidistant from the center of a hollow tool head on radii spaced 120.degree. apart. Each roller has a thin flange; the three flanges lie in a single plane to form an internal circumferential rib in a rotating tubular workpiece. The tool head has two complementary parts with two rollers in one part of the head and one roller in the other part; the two parts are joined by a hinge. A second hinge, located so the rollers are between the two hinges, connects one of the parts to a tool bar mounted in a lathe tool holder. The axes of rotation of both hinges and all three rollers are parallel. A hole exposing equal portions of the three roller flanges is located in the center of the tool head. The two hinges permit the tool head to be opened and rotated slightly downward, taking the roller flanges out of the path of the workpiece which is supported on both ends and rotated by the lathe. The parts of the tool head are then closed on the workpiece so that the flanges are applied to the workpiece and form the rib. The tool is then relocated for forming of the next rib.

  7. Dynamic Forms. Part 1: Functions

    NASA Technical Reports Server (NTRS)

    Meyer, George; Smith, G. Allan

    1993-01-01

    The formalism of dynamic forms is developed as a means for organizing and systematizing the design control systems. The formalism allows the designer to easily compute derivatives to various orders of large composite functions that occur in flight-control design. Such functions involve many function-of-a-function calls that may be nested to many levels. The component functions may be multiaxis, nonlinear, and they may include rotation transformations. A dynamic form is defined as a variable together with its time derivatives up to some fixed but arbitrary order. The variable may be a scalar, a vector, a matrix, a direction cosine matrix, Euler angles, or Euler parameters. Algorithms for standard elementary functions and operations of scalar dynamic forms are developed first. Then vector and matrix operations and transformations between parameterization of rotations are developed in the next level in the hierarchy. Commonly occurring algorithms in control-system design, including inversion of pure feedback systems, are developed in the third level. A large-angle, three-axis attitude servo and other examples are included to illustrate the effectiveness of the developed formalism. All algorithms were implemented in FORTRAN code. Practical experience shows that the proposed formalism may significantly improve the productivity of the design and coding process.

  8. 48 CFR 253.303 - Agency forms.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 3 2013-10-01 2013-10-01 false Agency forms. 253.303 Section 253.303 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CLAUSES AND FORMS FORMS Illustration of Forms 253.303 Agency forms. DoD forms...

  9. 48 CFR 253.303 - Agency forms.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false Agency forms. 253.303 Section 253.303 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CLAUSES AND FORMS FORMS Illustration of Forms 253.303 Agency forms. DoD forms...

  10. 48 CFR 253.303 - Agency forms.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 3 2012-10-01 2012-10-01 false Agency forms. 253.303 Section 253.303 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CLAUSES AND FORMS FORMS Illustration of Forms 253.303 Agency forms. DoD forms...

  11. 48 CFR 253.303 - Agency forms.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 3 2011-10-01 2011-10-01 false Agency forms. 253.303 Section 253.303 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CLAUSES AND FORMS FORMS Illustration of Forms 253.303 Agency forms. DoD forms...

  12. [Adult form of Pompe disease].

    PubMed

    Ziółkowska-Graca, Bozena; Kania, Aleksander; Zwolińska, Grazyna; Nizankowska-Mogilnicka, Ewa

    2008-01-01

    Pompe disease (glycogen-storage disease type II) is an autosomal recessive disorder caused by a deficiency of lysosomal acid alpha-glucosidase (GAA), leading to the accumulation of glycogen in the lysosomes primarily in muscle cells. In the adult form of the disease, proximal muscle weakness is noted and muscle volume is decreased. The infantile form is usually fatal. In the adult form of the disease the prognosis is relatively good. Muscle weakness may, however, interfere with normal daily activities, and respiratory insufficiency may be associated with obstructive sleep apnea. Death usually results from respiratory failure. Effective specific treatment is not available. Enzyme replacement therapy with recombinant human GAA (rh-GAA) still remains a research area. We report the case of a 24-year-old student admitted to the Department of Pulmonary Diseases because of severe respiratory insufficiency. Clinical symptoms such as dyspnea, muscular weakness and increased daytime sleepiness had been progressing for 2 years. Clinical examination and increased blood levels of CK suggested muscle pathology. Histopathological analysis of muscle biopsy, performed under electron microscope, confirmed the presence of vacuoles containing glycogen. Specific enzymatic activity of alpha-glucosidase was analyzed confirming Pompe disease. The only effective method to treat respiratory insufficiency was bi-level positive pressure ventilation. Respiratory rehabilitation was instituted and is still continued by the patient at home. A high-protein, low-sugar diet was proposed for the patient. Because of poliglobulia low molecular weight heparin was prescribed. The patient is eligible for experimental replacement therapy with rh-GAA. PMID:19003770

  13. Weak Energy: Form and Function

    NASA Astrophysics Data System (ADS)

    Parks, Allen D.

    The equation of motion for a time-dependent weak value of a quantum mechanical observable contains a complex valued energy factor—the weak energy of evolution. This quantity is defined by the dynamics of the pre-selected and post-selected states which specify the observable's weak value. It is shown that this energy: (i) is manifested as dynamical and geometric phases that govern the evolution of the weak value during the measurement process; (ii) satisfies the Euler-Lagrange equations when expressed in terms of Pancharatnam (P) phase and Fubini-Study (FS) metric distance; (iii) provides for a PFS stationary action principle for quantum state evolution; (iv) time translates correlation amplitudes; (v) generalizes the temporal persistence of state normalization; and (vi) obeys a time-energy uncertainty relation. A similar complex valued quantity—the pointed weak energy of an evolving quantum state—is also defined and several of its properties in PFS coordinates are discussed. It is shown that the imaginary part of the pointed weak energy governs the state's survival probability and its real part is—to within a sign—the Mukunda-Simon geometric phase for arbitrary evolutions or the Aharonov-Anandan (AA) geometric phase for cyclic evolutions. Pointed weak energy gauge transformations and the PFS 1-form are defined and discussed and the relationship between the PFS 1-form and the AA connection 1-form is established. [Editors note: for a video of the talk given by Prof. Parks at the Aharonov-80 conference in 2012 at Chapman University, see http://quantum.chapman.edu/talk-25.

  14. CERAMIC WASTE FORM DATA PACKAGE

    SciTech Connect

    Amoroso, J.; Marra, J.

    2014-06-13

    The purpose of this data package is to provide information about simulated crystalline waste forms that can be used to select an appropriate composition for a Cold Crucible Induction Melter (CCIM) proof of principle demonstration. Melt processing, viscosity, electrical conductivity, and thermal analysis information was collected to assess the ability of two potential candidate ceramic compositions to be processed in the Idaho National Laboratory (INL) CCIM and to guide processing parameters for the CCIM operation. Given uncertainties in the CCIM capabilities to reach certain temperatures throughout the system, one waste form designated 'Fe-MP' was designed towards enabling processing and another, designated 'CAF-5%TM-MP' was designed towards optimized microstructure. Melt processing studies confirmed both compositions could be poured from a crucible at 1600{degrees}C although the CAF-5%TM-MP composition froze before pouring was complete due to rapid crystallization (upon cooling). X-ray diffraction measurements confirmed the crystalline nature and phase assemblages of the compositions. The kinetics of melting and crystallization appeared to vary significantly between the compositions. Impedance spectroscopy results indicated the electrical conductivity is acceptable with respect to processing in the CCIM. The success of processing either ceramic composition will depend on the thermal profiles throughout the CCIM. In particular, the working temperature of the pour spout relative to the bulk melter which can approach 1700{degrees}C. The Fe-MP composition is recommended to demonstrate proof of principle for crystalline simulated waste forms considering the current configuration of INL's CCIM. If proposed modifications to the CCIM can maintain a nominal temperature of 1600{degrees}C throughout the melter, drain, and pour spout, then the CAF-5%TM-MP composition should be considered for a proof of principle demonstration.

  15. FORMING PROTECTIVE FILMS ON METAL

    DOEpatents

    Gurinsky, D.H.; Kammerer, O.F.; Sadofsky, J.; Weeks, J.R.

    1958-12-16

    Methods are described of inhibiting the corrosion of ferrous metal by contact with heavy liquid metals such as bismuth and gallium at temperatures above 500 icient laborato C generally by bringing nltrogen and either the metal zirconium, hafnium, or titanium into reactlve contact with the ferrous metal to form a thin adherent layer of the nitride of the metal and thereafter maintaining a fractional percentage of the metal absorbed in the heavy liquid metal in contact with the ferrous metal container. The general purpose for uslng such high boiling liquid metals in ferrous contalners would be as heat transfer agents in liquid-metal-fueled nuclear reactors.

  16. Export of newly formed LSW

    NASA Astrophysics Data System (ADS)

    Müller, Katharina; Klein, Birgit; Karstensen, Johannes; Fischer, Jürgen; Baumann, Till; Kanzow, Torsten

    2015-04-01

    The Atlantic meridional overturning circulation represents the strongest mechanism for oceanic northward heat transport. This is accomplished by moving warm water northward in the upper ocean compensated by a deep return flow of cold and dense North Atlantic Deep Water (NADW). Labrador Sea Water (LSW) constitutes the shallowest component of NADW. Since LSW is also supposed to be the most sensitive NADW component to climate change it is of particular interest. LSW is formed by deep convection not only in the centre of the Labrador Sea but also near its western boundary. Recent studies have suggested that LSW formed in the boundary region enters its export route from the Labrador Sea, the Deep Western Boundary Current, faster than LSW originating from the central Labrador Sea. In this study the spatial and temporal evolution of the export of newly formed LSW is investigated. For this purpose hydrographic mooring data from an array located at the western bounndary at 53°N starting in the late 1990s until 2014 and data from the Argo float network is used. The averaged seasonal salinity cycle at the array, particularly at the moorings further onshore, shows a pronounced freshwater signal in May indicating the arrival of newly formed LSW in the boundary current. In order to learn more about its preceding pathway and the corresponding export timescale the mooring data is complemented by data from Argo floats. Besides the annual cycles of LSW formation and export, their interannual variations are important aspects affecting the large-scale circulation. For instance, in years of relatively strong convection, as in 2008 and 2012, LSW is observed to pass the boundary current array at 53°N earlier, i.e. in February and March, respectively, than in years with weak convection, as in 2007 or 2010. Besides seasonal variations in the boundary current, a possible explanation for the earlier freshwater signal in years of enhanced convection might be a shift in convection sites

  17. 76 FR 21946 - Proposed Collection; Comment Request for Form 990-BL; Schedule A (Form 990-BL), Form 6069

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-19

    ... Internal Revenue Service Proposed Collection; Comment Request for Form 990-BL; Schedule A (Form 990-BL), Form 6069 AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Notice and request for comments... Form 990-BL, Schedule A (Form 990-BL), Information and Initial Excise Tax Return for Black Lung...

  18. Gravity, light and plant form.

    PubMed

    Hangarter, R P

    1997-06-01

    Plants have evolved highly sensitive and selective mechanisms that detect and respond to various aspects of their environment. As a plant develops, it integrates the environmental information perceived by all of its sensory systems and adapts its growth to the prevailing environmental conditions. Light is of critical importance because plants depend on it for energy and, thus, survival. The quantity, quality and direction of light are perceived by several different photosensory systems that together regulate nearly all stages of plant development, presumably in order to maintain photosynthetic efficiency. Gravity provides an almost constant stimulus that is the source of critical spatial information about its surroundings and provides important cues for orientating plant growth. Gravity plays a particularly important role during the early stages of seedling growth by stimulating a negative gravitropic response in the primary shoot that orientates it towards the source of light, and a positive gravitropic response in the primary root that causes it to grow down into the soil, providing support and nutrient acquisition. Gravity also influences plant form during later stages of development through its effect on lateral organs and supporting structures. Thus, the final form of a plant depends on the cumulative effects of light, gravity and other environmental sensory inputs on endogenous developmental programs. This article is focused on developmental interactions modulated by light and gravity.

  19. [Kinin forming system and ovulation].

    PubMed

    Seki, M

    1984-06-01

    The aim of the study is to clarify the role of the kinin forming system on ovulation. The results were as follows, Plasma prekallikrein of superovulated prepubertal rats was decreased to 50-60% of the normal level after PMS injection and 80-90% of the normal level after hCG injection. The lowest level was 33.8% 39 hours after PMS injection. Aprotinin suppressed the superovulation of prepubertal rats at doses of 16.7 X 10(4) KIE and 37.8 X 10(4) KIE (p less than 0.01). These results showed that the kinin production system has an effect on ovulation. As the sex steroid hormone, estradil benzoate, progesterone and testosterone propinate were used in oophorectomized mice. They had no effect on the plasma prekallikrein level. The plasma prekallikrein level during the estrus cycle of mature female mice was 85.5% of the control level in preestrus, 80.3% in estrus, 83.7% in metestrus and 89.8% in diestrus. The mean was 83.9%, which was significantly lower than that for oophorectomized mice (94.1%). It is proved that plasma prekallikrein was consumed and the kinin forming system was accelerated in the ovary with ovulation. PMID:6205107

  20. Gravity, light and plant form.

    PubMed

    Hangarter, R P

    1997-06-01

    Plants have evolved highly sensitive and selective mechanisms that detect and respond to various aspects of their environment. As a plant develops, it integrates the environmental information perceived by all of its sensory systems and adapts its growth to the prevailing environmental conditions. Light is of critical importance because plants depend on it for energy and, thus, survival. The quantity, quality and direction of light are perceived by several different photosensory systems that together regulate nearly all stages of plant development, presumably in order to maintain photosynthetic efficiency. Gravity provides an almost constant stimulus that is the source of critical spatial information about its surroundings and provides important cues for orientating plant growth. Gravity plays a particularly important role during the early stages of seedling growth by stimulating a negative gravitropic response in the primary shoot that orientates it towards the source of light, and a positive gravitropic response in the primary root that causes it to grow down into the soil, providing support and nutrient acquisition. Gravity also influences plant form during later stages of development through its effect on lateral organs and supporting structures. Thus, the final form of a plant depends on the cumulative effects of light, gravity and other environmental sensory inputs on endogenous developmental programs. This article is focused on developmental interactions modulated by light and gravity. PMID:11541207

  1. Gravity, light and plant form

    NASA Technical Reports Server (NTRS)

    Hangarter, R. P.

    1997-01-01

    Plants have evolved highly sensitive and selective mechanisms that detect and respond to various aspects of their environment. As a plant develops, it integrates the environmental information perceived by all of its sensory systems and adapts its growth to the prevailing environmental conditions. Light is of critical importance because plants depend on it for energy and, thus, survival. The quantity, quality and direction of light are perceived by several different photosensory systems that together regulate nearly all stages of plant development, presumably in order to maintain photosynthetic efficiency. Gravity provides an almost constant stimulus that is the source of critical spatial information about its surroundings and provides important cues for orientating plant growth. Gravity plays a particularly important role during the early stages of seedling growth by stimulating a negative gravitropic response in the primary shoot that orientates it towards the source of light, and a positive gravitropic response in the primary root that causes it to grow down into the soil, providing support and nutrient acquisition. Gravity also influences plant form during later stages of development through its effect on lateral organs and supporting structures. Thus, the final form of a plant depends on the cumulative effects of light, gravity and other environmental sensory inputs on endogenous developmental programs. This article is focused on developmental interactions modulated by light and gravity.

  2. Integrally formed radio frequency quadrupole

    DOEpatents

    Abbott, Steven R.

    1989-01-01

    An improved radio frequency quadrupole (10) is provided having an elongate housing (11) with an elongate central axis (12) and top, bottom and two side walls (13a-d) symmetrically disposed about the axis, and vanes (14a-d) formed integrally with the walls (13a-d), the vanes (14a-d) each having a cross-section at right angles to the central axis (12) which tapers inwardly toward the axis to form electrode tips (15a-d) spaced from each other by predetermined distances. Each of the four walls (13a-d), and the vanes (14a-d) integral therewith, is a separate structural element having a central lengthwise plane (16) passing through the tip of the vane, the walls (13a-d) having flat mounting surfaces (17, 18) at right angles to and parallel to the control plane (16), respectively, which are butted together to position the walls and vane tips relative to each other.

  3. Preventing Ice Before it Forms

    NASA Technical Reports Server (NTRS)

    2006-01-01

    In the late 1990s, a team of engineers at Ames Research Center invented an anti-icing fluid to keep ice from building up on airplane wings. Ice on wings can be a serious safety hazard, especially during takeoff, when a sheet of ice the thickness of a compact disc can reduce lift by 25 percent or more. The typical approach to clearing off the ice is to use a deicing solution once the ice has built up. The fluid created by the Ames team, though, when applied to a dry surface, prevents the ice from even forming a surface bond, which saves deicing time and money, while also preventing excessive use of chemical solvents. If, however, the solution is not applied before ice forms, it also serves as a traditional deicing formula. The formula contains propylene glycol, which has a very low freezing point, and a thickener, which helps the fluid adhere to the surface. Ice gathers on top of the formula, and then it can be wiped off with little effort. This thickening agent, a pseudo-plastic, sprays on as a liquid, like lemonade, gels like a lemon sherbet, turns back to a liquid when wiped, and then gels again into its sherbet consistency when left to solidify. The sherbet-gel stage is especially important when the formula is sprayed onto a vertical or steeped surface, as it clings better than a liquid would.

  4. Coated particle waste form development

    NASA Astrophysics Data System (ADS)

    Oma, K. H.; Buckwalter, C. Q.; Chick, L. A.

    1981-12-01

    Coated particle waste forms were developed as part of the multibarrier concept. Primary efforts were to coat simulated nuclear waste glass marbles and ceramic pellets with low temperature pyrolytic carbon (LT-PyC) coatings via the process of chemical vapor deposition (CVD). Fluidized bed coaters, screw agitated coaters, and rotating tube coaters were used. Coating temperatures were reduced by using catalysts and plasma activation. In general, the LT-PyC coatings did not provide the expected high leach resistance as previously measured for carbon alone. The coatings were friable and often spalled off the substrate. A totally different concept, thermal spray coating, was investigated as an alternative to CVD coating. Flame spray, wire gun, and plasma gun systems were evaluated using glass, ceramic, and metallic coating materials. Metal plasma spray coatings (Al, Sn, Zn, Pb) provided a two to three orders of magnitude increase in chemical durability.

  5. Frozen Film and FOSDIC Forms

    PubMed Central

    RUGGLES, STEVEN; SCHROEDER, MATTHEW; RIVERS, NATASHA; ALEXANDER, J. TRENT; GARDNER, TODD K.

    2012-01-01

    In this article, the authors describe a collaboration of the Minnesota Population Center (MPC), the U.S. Census Bureau, and the National Archives and Records Administration to restore the lost data from the 1960 Census. The data survived on refrigerated microfilm in a cave in Lenexa, Kansas. The MPC is now converting the data to usable form. Once the restored data are processed, the authors intend to develop three new data sources based on the 1960 census. These data will replace the most inadequate sample in the series of public-use census microdata spanning the years from 1850 to 2000, extend the chronological scope of the public census summary files, and provide a powerful new resource for the Census Bureau and its Research Data Centers. PMID:22544986

  6. Forming impressions from incongruent traits.

    PubMed

    Casselden, P A; Hampson, S E

    1990-08-01

    The factors that affect the ease with which impressions are formed from incongruent trait pairs are investigated. In Experiments 1 and 2, trait pairs that were both descriptively and evaluatively congruent, as well as ones that were only evaluatively congruent, were found to be more imaginable and to be perceived as more frequently co-occurring than incongruent trait pairs. In Experiment 3, response latency provided a converging measure of ease of imaginability. Experiment 4 examined written descriptions of targets described by these trait pairs, and found more attempts to integrate the congruent than the incongruent pairs. These findings are discussed in terms of the relation between laypersons' impressions of personality and formal personality assessment.

  7. Forming parts over small radii

    NASA Astrophysics Data System (ADS)

    Hazra, S. K.; Hughes, D. J.; Pereira, M. P.; Rolfe, B. F.

    2016-08-01

    Stamping simulations usually make the plane stress simplifying assumption. However, this becomes less valid when material draws around features with radius to sheet thickness ratios less than 20. Pereira, Yan & Rolfe (Wear, Vol.265, p.1687 (2008)) predicted that out-of-plane stress equivalent to material yield can occur because a line contact forms briefly at the start of the draw process. The high transient stress can cause high rates of tool wear and may cause the ‘die impact line’ cosmetic defect. In this work, we present residual strain results of a channel section that was drawn over a small radius. Using the neutron source at the Institut Laue-Langevin, in-plane and out-of-plane strains were measured in the channel part to show some support for the conclusions of Pereira et. al.

  8. Method for forming energetic nanopowders

    DOEpatents

    Lee, Kien-Yin; Asay, Blaine W.; Kennedy, James E.

    2013-10-15

    A method for the preparation of neat energetic powders, having nanometer dimensions, is described herein. For these neat powder, a solution of a chosen energetic material is prepared in an aprotic solvent and later combined with liquid hexane that is miscible with such solvent. The energetic material chosen is less soluble in the liquid hexane than in the aprotic solvent and the liquid hexane is cooled to a temperature that is below that of the solvent solution. In order to form a precipitate of said neat powders, the solvent solution is rapidly combined with the liquid hexane. When the resulting precipitate is collected, it may be dried and filtered to yield an energetic nanopowder material.

  9. [Familial form of rheumatoid nodulosis].

    PubMed

    Bosser, H; Schubert, B; Grosshans, E

    1993-01-01

    We report a familial form of rheumatoid nodulosis where the early lesions appeared in the first years of life in a young man and his son. The numerous papular and nodular skin lesions disclosed an ulcerative evolution leaving atrophic scars mainly near the limbs' joints. In both patients the evolution was characterized by the late onset of polyarthralgias and of a non-destructive seronegative polyarthritis; intra-osseous lesions were present in the metatarsal bones in the father. Rheumatoid nodulosis is a rare disease, sometimes considered as a benign variant of rheumatoid arthritis without destructive joint involvement. A serum rheumatoid factor is inconstantly present and the intra-osseous geodes have been shown to be rheumatoid nodules exhibiting the same histological structures of palisading granulomas as the subcutaneous nodules. The main symptom of the disease is the occurrence of multiple nodules followed by the delayed onset of a polyarthritis with a benign course without systemic involvement.

  10. Localization and real Jacobi forms

    NASA Astrophysics Data System (ADS)

    Ashok, Sujay K.; Doroud, Nima; Troost, Jan

    2014-04-01

    We calculate the elliptic genus of two dimensional abelian gauged linear sigma models with (2, 2) supersymmetry using supersymmetric localization. The matter sector contains charged chiral multiplets as well as Stückelberg fields coupled to the vector multiplets. These models include theories that flow in the infrared to non-linear sigma models with target spaces that are non-compact Kähler manifolds with U( N) isometry and with an asymptotically linear dilaton direction. The elliptic genera are the modular completions of mock Jacobi forms that have been proposed recently using complementary arguments. We also compute the elliptic genera of models that contain multiple Stückelberg fields from first principles.

  11. Form factors from lattice QCD

    SciTech Connect

    Dru Renner

    2012-04-01

    Precision computation of hadronic physics with lattice QCD is becoming feasible. The last decade has seen precent-level calculations of many simple properties of mesons, and the last few years have seen calculations of baryon masses, including the nucleon mass, accurate to a few percent. As computational power increases and algorithms advance, the precise calculation of a variety of more demanding hadronic properties will become realistic. With this in mind, I discuss the current lattice QCD calculations of generalized parton distributions with an emphasis on the prospects for well-controlled calculations for these observables as well. I will do this by way of several examples: the pion and nucleon form factors and moments of the nucleon parton and generalized-parton distributions.

  12. Miscellaneous Waste-Form FEPs

    SciTech Connect

    A. Schenker

    2000-12-08

    The US DOE must provide a reasonable assurance that the performance objectives for the Yucca Mountain Project (YMP) potential radioactive-waste repository can be achieved for a 10,000-year post-closure period. The guidance that mandates this direction is under the provisions of 10 CFR Part 63 and the US Department of Energy's ''Revised Interim Guidance Pending Issuance of New US Nuclear Regulatory Commission (NRC) Regulations (Revision 01, July 22, 1999), for Yucca Mountain, Nevada'' (Dyer 1999 and herein referred to as DOE's Interim Guidance). This assurance must be demonstrated in the form of a performance assessment that: (1) identifies the features, events, and processes (FEPs) that might affect the performance of the potential geologic repository; (2) examines the effects of such FEPs on the performance of the potential geologic repository; (3) estimates the expected annual dose to a specified receptor group; and (4) provides the technical basis for inclusion or exclusion of specific FEPs.

  13. Forming impressions from incongruent traits.

    PubMed

    Casselden, P A; Hampson, S E

    1990-08-01

    The factors that affect the ease with which impressions are formed from incongruent trait pairs are investigated. In Experiments 1 and 2, trait pairs that were both descriptively and evaluatively congruent, as well as ones that were only evaluatively congruent, were found to be more imaginable and to be perceived as more frequently co-occurring than incongruent trait pairs. In Experiment 3, response latency provided a converging measure of ease of imaginability. Experiment 4 examined written descriptions of targets described by these trait pairs, and found more attempts to integrate the congruent than the incongruent pairs. These findings are discussed in terms of the relation between laypersons' impressions of personality and formal personality assessment. PMID:2213498

  14. Alumina forming iron base superalloy

    DOEpatents

    Yamamoto, Yukinori; Muralidharan, Govindarajan; Brady, Michael P.

    2014-08-26

    An austenitic stainless steel alloy, consists essentially of, in weight percent 2.5 to 4 Al; 25 to 35 Ni; 12 to 19 Cr; at least 1, up to 4 total of at least one element selected from the group consisting of Nb and Ta; 0.5 to 3 Ti; less than 0.5 V; 0.1 to 1 of at least on element selected from the group consisting of Zr and Hf; 0.03 to 0.2 C; 0.005 to 0.1 B; and base Fe. The weight percent Fe is greater than the weight percent Ni. The alloy forms an external continuous scale including alumina, and contains coherent precipitates of .gamma.'-Ni.sub.3Al, and a stable essentially single phase FCC austenitic matrix microstructure. The austenitic matrix is essentially delta-ferrite-free and essentially BCC-phase-free.

  15. Nuclear waste forms for actinides

    PubMed Central

    Ewing, Rodney C.

    1999-01-01

    The disposition of actinides, most recently 239Pu from dismantled nuclear weapons, requires effective containment of waste generated by the nuclear fuel cycle. Because actinides (e.g., 239Pu and 237Np) are long-lived, they have a major impact on risk assessments of geologic repositories. Thus, demonstrable, long-term chemical and mechanical durability are essential properties of waste forms for the immobilization of actinides. Mineralogic and geologic studies provide excellent candidate phases for immobilization and a unique database that cannot be duplicated by a purely materials science approach. The “mineralogic approach” is illustrated by a discussion of zircon as a phase for the immobilization of excess weapons plutonium. PMID:10097054

  16. 48 CFR 813.307 - Forms.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... following forms provide a purchase or delivery order, vendor's invoice, and receiving report: (1) VA Form 90... Form 10-7078, Authorization and Invoice for Medical and Hospital Services. (2) VA Form 10-7079, Request for Outpatient Medical Services. (3) VA Form 10-2570d, Dental Record Authorization and Invoice...

  17. 48 CFR 813.307 - Forms.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... following forms provide a purchase or delivery order, vendor's invoice, and receiving report: (1) VA Form 90... Form 10-7078, Authorization and Invoice for Medical and Hospital Services. (2) VA Form 10-7079, Request for Outpatient Medical Services. (3) VA Form 10-2570d, Dental Record Authorization and Invoice...

  18. Ynamides in Ring Forming Transformations

    PubMed Central

    WANG, XIAO-NA; YEOM, HYUN-SUK; FANG, LI-CHAO; HE, SHUZHONG; MA, ZHI-XIONG; KEDROWSKI, BRANT L.; HSUNG, RICHARD P.

    2013-01-01

    Conspectus The ynamide functional group activates carbon-carbon triple bonds through an attached nitrogen atom that bears an electron-withdrawing group. As a result, the alkyne has both electrophilic and nucleophilic properties. Through the selection of the electron-withdrawing group attached to nitrogen chemists can modulate the electronic properties and reactivity of ynamides, making these groups versatile synthetic building blocks. The reactions of ynamides also lead directly to nitrogen-containing products, which provides access to important structural motifs found in natural products and molecules of medicinal interest. Therefore, researchers have invested increasing time and research in the chemistry of ynamides in recent years. This Account surveys and assesses new organic transformations involving ynamides developed in our laboratory and in others around the world. We showcase the synthetic power of ynamides for rapid assembly of complex molecular structures. Among the recent reports of ynamide transformations, ring-forming reactions provide a powerful tool for generating molecular complexity quickly. In addition to their synthetic utility, such reactions are mechanistically interesting. Therefore, we focus primarily on the cyclization chemistry of ynamides. This Account highlights ynamide reactions that are useful in the rapid synthesis of cyclic and polycyclic structural manifolds. We discuss the mechanisms active in the ring formations and describe representative examples that demonstrate the scope of these reactions and provide mechanistic insights. In this discussion we feature examples of ynamide reactions involving radical cyclizations, ring-closing metathesis, transition metal and non-transition metal mediated cyclizations, cycloaddition reactions, and rearrangements. The transformations presented rapidly introduce structural complexity and include nitrogen within, or in close proximity to, a newly formed ring (or rings). Thus, ynamides have emerged

  19. 48 CFR 2913.307 - Forms.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., contracting officers are encouraged to use the Standard Form (SF) SF-1449, when executing commercial acquisitions. Agencies may use forms other than the SF-1449 and may print on those forms the clauses...

  20. 48 CFR 3053.303 - Agency forms.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... section illustrates agency-specified forms. To access these forms go to: http://www.dhs.gov (under “Business, Acquisition Information”) or https://dhsonline.dhs.gov/portal/jhtml/general/forms.jhtml....

  1. Detection of combustion formed nanoparticles.

    PubMed

    Sgro, L A; Basile, G; Barone, A C; D'Anna, A; Minutolo, P; Borghese, A; D'Alessio, A

    2003-06-01

    UV-visible extinction and scattering and two extra situ sampling techniques: atomic force microscopy (AFM) and differential mobility analysis (DMA) are used to follow the evolution of the particles formed in flames. These particle sizing techniques were chosen because of their sensitivity to detect inception particles, which have diameters, d<5 nm, too small to be observed with typical particle measurement instrumentation. The size of the particles determined by AFM and DMA compares well with the size determined by in situ optical measurements, indicating that the interpretation of the UV-visible optical signal is quite good, and strongly showing the presence of d=2-4 nm particles. UV-visible extinction measurements are also used to determine the concentration of d=2-4 nm particles at the exhausts of practical combustion systems. A numerical model, able to reproduce the experimentally observed low coagulation rate of nanoparticles with respect to soot particles, is used to investigate the operating conditions in the combustion chamber and exhaust system for which 2-4 nm particles survive the exhaust or grow to larger sizes. Combustion generated nanoparticles are suspected to affect human and environmental health because of their affinity for water, small size, low rate of coagulation, and large surface area/weight ratio. The ability to isolate nanoparticles from soot particles in hydrosols collected from combustion may be useful for future analysis by a variety of techniques and toxicological assays.

  2. Dyadosphere formed in gravitational collapse

    SciTech Connect

    Ruffini, Remo; Xue Shesheng

    2008-10-10

    We first recall the concept of Dyadosphere (electron-positron-photon plasma around a formed black holes) and its motivation, and recall on (i) the Dirac process: annihilation of electron-positron pairs to photons; (ii) the Breit-Wheeler process: production of electron-positron pairs by photons with the energy larger than electron-positron mass threshold; the Sauter-Euler-Heisenberg effective Lagrangian and rate for the process of electron-positron production in a constant electric field. We present a general formula for the pair-production rate in the semi-classical treatment of quantum mechanical tunneling. We also present in the Quantum Electro-Dynamics framework, the calculations of the Schwinger rate and effective Lagrangian for constant electromagnetic fields. We give a review on the electron-positron plasma oscillation in constant electric fields, and its interaction with photons leading to energy and number equipartition of photons, electrons and positrons. The possibility of creating an overcritical field in astrophysical condition is pointed out. We present the discussions and calculations on (i) energy extraction from gravitational collapse; (ii) the formation of Dyadosphere in gravitational collapsing process, and (iii) its hydrodynamical expansion in Reissner Nordstroem geometry. We calculate the spectrum and flux of photon radiation at the point of transparency, and make predictions for short Gamma-Ray Bursts.

  3. Filtrating forms of soil bacteria

    NASA Astrophysics Data System (ADS)

    Van'kova, A. A.; Ivanov, P. I.; Emtsev, V. T.

    2013-03-01

    Filtrating (ultramicroscopic) forms (FF) of bacteria were studied in a soddy-podzolic soil and the root zone of alfalfa plants as part of populations of the most widespread physiological groups of soil bacteria. FF were obtained by filtering soil solutions through membrane filters with a pore diameter of 0.22 μm. It was established that the greater part of the bacteria in the soil and in the root zone of the plants has an ultramicroscopic size: the average diameter of the cells is 0.3 μm, and their length is 0.6 μm, which is significantly less than the cell size of banal bacteria. The number of FF varies within a wide range depending on the physicochemical conditions of the habitat. The FF number's dynamics in the soil is of a seasonal nature; i.e., the number of bacteria found increases in the summer and fall and decreases in the winter-spring period. In the rhizosphere of the alfalfa, over the vegetation period, the number of FF and their fraction in the total mass of the bacteria increase. A reverse tendency is observed in the rhizoplane. The morphological particularities (identified by an electron microscopy) and the nature of the FF indicate their physiological activity.

  4. Interactions of form and orientation

    NASA Technical Reports Server (NTRS)

    Mittelstaedt, Horst

    1989-01-01

    It is well known that the orientation of an optical pattern relative to egocentric or extraneous references affects its figural quality, that is, alters its perceived form and concomitantly delays or quickens its identification (Rock 1973). A square presented in the frontal plane to an upright person (S), for instance, changes from a box to a diamond when it is rotated with respect to the S's median plane by 45 deg. This angle, that is, the angle between the orientations of the pattern in which the two apparent figures (Gestalten) attain a summit of purity and distinctness, will be called the figural disparity of the pattern. If, as in this case, the S is upright, the retinal meridian and the subjective vertical (SV) are both in the viewer's median plane. The question arises with respect to which of these orientation references the two figures are identified. The answer may be found when the pattern and the S are oriented in such a way that the projections of the retinal meridian and the SV into the plane of the pattern diverge by the pattern's figural disparity or its periodic multiples: that is, in this case of a square by 45 or 135 deg, respectively. Similarly, which reference determines whether an equilateral triangle is seen as a pyramid or a traffic warning sign may be revealed at a divergence of SV and retinal meridian of 60 or 180 deg, respectively. It is generally found that for head roll tilts (Rho) and figural disparities of up to 90 deg, the figure whose axis coincides with the SV is seen. At head tilts of Rho=180 deg, however, the retinal reference dominates, as a rule independently of the figural disparity.

  5. Uniform-droplet spray forming

    SciTech Connect

    Blue, C.A.; Sikka, V.K.; Chun, Jung-Hoon; Ando, T.

    1997-04-01

    The uniform-droplet process is a new method of liquid-metal atomization that results in single droplets that can be used to produce mono-size powders or sprayed-on to substrates to produce near-net shapes with tailored microstructure. The mono-sized powder-production capability of the uniform-droplet process also has the potential of permitting engineered powder blends to produce components of controlled porosity. Metal and alloy powders are commercially produced by at least three different methods: gas atomization, water atomization, and rotating disk. All three methods produce powders of a broad range in size with a very small yield of fine powders with single-sized droplets that can be used to produce mono-size powders or sprayed-on substrates to produce near-net shapes with tailored microstructures. The economical analysis has shown the process to have the potential of reducing capital cost by 50% and operating cost by 37.5% when applied to powder making. For the spray-forming process, a 25% savings is expected in both the capital and operating costs. The project is jointly carried out at Massachusetts Institute of Technology (MIT), Tuffs University, and Oak Ridge National Laboratory (ORNL). Preliminary interactions with both finished parts and powder producers have shown a strong interest in the uniform-droplet process. Systematic studies are being conducted to optimize the process parameters, understand the solidification of droplets and spray deposits, and develop a uniform-droplet-system (UDS) apparatus appropriate for processing engineering alloys.

  6. 31 CFR 1.35 - Information forms.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Information forms. 1.35 Section 1.35... § 1.35 Information forms. (a) Review of forms. Except for forms developed and used by constituent... developed and used by the Department of the Treasury to collect information from and about individuals....

  7. 48 CFR Appendix - List of IAAR Forms

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Acquisition Regulations System BROADCASTING BOARD OF GOVERNORS CLAUSES AND FORMS Reserved List of IAAR Forms 1953.370-21The Broadcasting Board of Governors Form IA-21, Abstract of Quotations. 1953.370-44The Broadcasting Board of Governors Form IA-44, Requisition-Purchase—Order-Invoice for Professional Services....

  8. Completing cremation forms: a practical guide.

    PubMed

    Proctor, Ian; Winstanley, Alison

    2013-07-01

    Before a body can be cremated doctors must complete a series of lengthy forms better known as 'crem forms'. One doctor first completes a medical certificate (Cremation Form 4, previously known as 'Part B') while a second must complete a confirmatory medical certificate (Cremation Form 5, previously 'Part C').

  9. 8 CFR 299.1 - Prescribed forms.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Prescribed forms. 299.1 Section 299.1 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS IMMIGRATION FORMS § 299.1 Prescribed forms. A listing of USCIS, ICE, and CBP approved forms referenced in chapter I can be viewed...

  10. 8 CFR 299.1 - Prescribed forms.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Prescribed forms. 299.1 Section 299.1 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS IMMIGRATION FORMS § 299.1 Prescribed forms. A listing of USCIS, ICE, and CBP approved forms referenced in chapter I can be viewed...

  11. 8 CFR 299.1 - Prescribed forms.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Prescribed forms. 299.1 Section 299.1 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS IMMIGRATION FORMS § 299.1 Prescribed forms. A listing of USCIS, ICE, and CBP approved forms referenced in chapter I can be viewed...

  12. Completing cremation forms: a practical guide.

    PubMed

    Proctor, Ian; Winstanley, Alison

    2013-07-01

    Before a body can be cremated doctors must complete a series of lengthy forms better known as 'crem forms'. One doctor first completes a medical certificate (Cremation Form 4, previously known as 'Part B') while a second must complete a confirmatory medical certificate (Cremation Form 5, previously 'Part C'). PMID:24145671

  13. Stability of polymorphic forms of ranitidine hydrochloride.

    PubMed

    Wu, V; Rades, T; Saville, D J

    2000-07-01

    Ranitidine-HCl can exist in two different polymorphic forms: form I (m.p. 134-140 degrees C) and form II (m.p. 140-144 degrees C). In the present study the stability of form I of ranitidine-HCl to a selection of powder pretreatments, to reflect conditions which might occur in manufacturing procedures, and also to a limited range of storage conditions was investigated. The original samples of form I and form II used were characterised by X-ray powder diffraction (XRPD), hot stage microscopy (HSM) and differential scanning calorimetry (DSC). A quantitative XRPD method for determining the fraction of form II in the presence of form I was used. XRPD data were analysed using regression techniques and artificial neural networks (ANN). The quantitative XRPD technique was then used to monitor the relative proportion of form II in each treated sample. Pretreatments of form I included (i) mixing with form II or with common excipients (ii) compression and grinding (iii) contact with solvents (followed by drying) before storage. Storage conditions involved three temperatures (20 degrees C, 30 degrees C, 42 degrees C) and three relative humidities (45% RH; 55% RH; 75% RH). Samples were stored for a period of 6 months. A limited factorial design was used. No increase in the form II:form I ratio was observed in the following pretreatment processes: introduction of form II nuclei into form I; introduction of excipients to form I; compression of form I powder at 5 and 15 tons; normal mixing and grinding processes; addition of isopropanol (IPA) or water/IPA mix followed by drying. In the pretreatment process where water was added to form I powder (with most or all of the powder dissolving), drying of the liquefied mass led to a mix of form I and form II. On storage at room temperature (20-30 degrees C), low relative humidity (45-55% RH), and in an air-tight container there was no increase in the form II:form I ratio. Storage of form I/form II mixes, particularly at high humidity

  14. Pre-form ceramic matrix composite cavity and method of forming and method of forming a ceramic matrix composite component

    DOEpatents

    Monaghan, Philip Harold; Delvaux, John McConnell; Taxacher, Glenn Curtis

    2015-06-09

    A pre-form CMC cavity and method of forming pre-form CMC cavity for a ceramic matrix component includes providing a mandrel, applying a base ply to the mandrel, laying-up at least one CMC ply on the base ply, removing the mandrel, and densifying the base ply and the at least one CMC ply. The remaining densified base ply and at least one CMC ply form a ceramic matrix component having a desired geometry and a cavity formed therein. Also provided is a method of forming a CMC component.

  15. Transitional Forms of Corynebacterium acnes in Disease

    PubMed Central

    Zierdt, C. H.; Wertlake, P. T.

    1969-01-01

    A clear-cut triad of sequential Corynebacterium acnes transitional forms from disease has been discovered. This entity includes three major forms which are capable of stabilization in culture, the spherical, the intermediate, and the definitive C. acnes. During conversion or reversion among the three forms, a variety of forms with mixed characteristics was observed. The spherical form was gram-negative and osmotically fragile, but it possessed a vestigial cell wall and mesosomes which excluded it from the L forms. In lieu of the L-form designation, the term “transitional” was adopted for all forms leading up to the definitive C. acnes. Culture of the spherical form was successful only on Mycoplasma-type media. The intermediate form was gram-negative, had mixed spherical and filamentous morphology, and bore a striking resemblance to Streptobacillus moniliformis. Like the spherical form, it was nutritionally exacting. The definitive form of C. acnes was preceded by gram-positive transitional forms of C. acnes morphology. It lacked, however, the carbohydrases and proteinases of C. acnes and susceptibility to C. acnes bacteriophages. Reversion was often blocked at this stage. A series of blood cultures from a patient with endocarditis was studied. Postmortem stain sections of the heart-valve lesion included intracellular masses of gram-negative spherical organisms. Indirect fluorescent antibody staining of these masses was strongly positive with antiserum to the spherical form and weakly positive with antiserum to the intermediate form. Images PMID:4886295

  16. Four new polymorphic forms of suplatast tosilate.

    PubMed

    Nagai, Keiko; Ushio, Takanori; Miura, Hidenori; Nakamura, Takashi; Moribe, Kunikazu; Yamamoto, Keiji

    2014-01-01

    We found four new polymorphic forms (γ-, ε-, ζ-, and η-forms) of suplatast tosilate (ST) by recrystallization and seeding with ST-analogous compounds; three polymorphic forms (α-, β-, and δ-forms) of ST have been previously reported. The physicochemical properties of these new forms were investigated using infrared (IR) spectroscopy, solid-state nuclear magnetic resonance (NMR) spectroscopy, differential scanning calorimetry, and powder X-ray diffractometry. The presence of hydrogen bonds in the new forms was assessed from the IR and solid-state NMR spectra. The crystal structures of the ε- and η-forms were determined from their powder X-ray diffraction data using the direct space approach and the Monte Carlo method, followed by Rietveld refinement. The structures determined for the ε- and η-forms supported the presence of hydrogen bonds between the ST molecules, as the IR and solid-state NMR spectra indicated. The thermodynamic characteristics of the seven polymorphic forms were evaluated by determining the solubility of each form. The α-form was the most insoluble in 2-propanol at 35°C, and was thus concluded to be the most stable form. The ε-form was the most soluble, and a polymorphic transition from the ε- to the α-form was observed during solubility testing. PMID:24211359

  17. Crystallization behavior of nuclear waste forms

    SciTech Connect

    Rusin, J.M.; Lokken, R.O.; May, R.P.; Wald, J.W.

    1981-09-01

    Several waste form options have been or are being developed for the immobilization of high-level wastes. The final selection of a waste form must take into consideration both waste form product as well as process factors. Crystallization behavior has an important role in nuclear waste form technology. For glass or vitreous waste forms, crystallization is generally controlled to a minimum by appropriate glass formulation and heat treatment schedules. With glass ceramic waste forms, crystallization is essential to convert glass products to highly crystalline waste forms with a minimum residual glass content. In the case of ceramic waste forms, additives and controlled sintering schedules are used to contain the radionuclides in specific tailored crystalline phases.

  18. Developments in GDR metal forming technology assessed

    NASA Astrophysics Data System (ADS)

    Sickel, B.

    1985-02-01

    Technological developments in the German Democratic Republic in the area of metal forming are described. Work done by the Erfurt VEB Herbert Warnke Forming Technology Combine in machine tool production is highlighted.

  19. 7 CFR 51.3747 - Well formed.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Honey Dew and Honey Ball Type Melons Definitions § 51.3747 Well formed. Well formed means that the melon has the normal shape characteristic of...

  20. 7 CFR 51.3747 - Well formed.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Honey Dew and Honey Ball Type Melons Definitions § 51.3747 Well formed. Well formed means that the melon has the normal shape characteristic of...

  1. 48 CFR 53.107 - Obtaining forms.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... optional forms from the General Services Administration (GSA) by using GSA Supply Catalog - Office Products (see 41 CFR 101-26.302). Standard forms adapted for computer preparation (see 53.105) or with...

  2. 48 CFR 53.107 - Obtaining forms.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... optional forms from the General Services Administration (GSA) by using GSA Supply Catalog - Office Products (see 41 CFR 101-26.302). Standard forms adapted for computer preparation (see 53.105) or with...

  3. 48 CFR 53.107 - Obtaining forms.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... optional forms from the General Services Administration (GSA) by using GSA Supply Catalog - Office Products (see 41 CFR 101-26.302). Standard forms adapted for computer preparation (see 53.105) or with...

  4. 25 CFR 61.6 - Application forms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... whether application form is for a natural child or an adopted child of the parent through whom eligibility... relationship to applicant. (3) A control number for the purpose of keeping a record of forms...

  5. 7 CFR 51.2653 - Well formed.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Standards for Grades for Sweet Cherries 1 Definitions § 51.2653 Well formed. Well formed means that the cherry has the normal shape characteristic of the variety, except that mature well developed...

  6. 7 CFR 51.2653 - Well formed.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., CERTIFICATION, AND STANDARDS) United States Standards for Grades for Sweet Cherries 1 Definitions § 51.2653 Well formed. Well formed means that the cherry has the normal shape characteristic of the variety, except...

  7. 7 CFR 51.1317 - Well formed.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Standards for Winter Pears 1 Definitions § 51.1317 Well formed. Well formed means having the shape characteristic of the variety. Slight irregularities of shape from type which do not appreciably detract from...

  8. 7 CFR 51.1317 - Well formed.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Standards for Winter Pears 1 Definitions § 51.1317 Well formed. Well formed means having the shape characteristic of the variety. Slight irregularities of shape from type which do not appreciably detract from...

  9. 34 CFR 300.509 - Model forms.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 2 2011-07-01 2010-07-01 true Model forms. 300.509 Section 300.509 Education... DISABILITIES Procedural Safeguards Due Process Procedures for Parents and Children § 300.509 Model forms. (a) Each SEA must develop model forms to assist parents and public agencies in filing a due...

  10. 34 CFR 300.509 - Model forms.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 34 Education 2 2012-07-01 2012-07-01 false Model forms. 300.509 Section 300.509 Education... DISABILITIES Procedural Safeguards Due Process Procedures for Parents and Children § 300.509 Model forms. (a) Each SEA must develop model forms to assist parents and public agencies in filing a due...

  11. 34 CFR 300.509 - Model forms.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 34 Education 2 2014-07-01 2013-07-01 true Model forms. 300.509 Section 300.509 Education... DISABILITIES Procedural Safeguards Due Process Procedures for Parents and Children § 300.509 Model forms. (a) Each SEA must develop model forms to assist parents and public agencies in filing a due...

  12. 34 CFR 300.509 - Model forms.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 34 Education 2 2013-07-01 2013-07-01 false Model forms. 300.509 Section 300.509 Education... DISABILITIES Procedural Safeguards Due Process Procedures for Parents and Children § 300.509 Model forms. (a) Each SEA must develop model forms to assist parents and public agencies in filing a due...

  13. Two Forms of Philosophical Argument or Critique

    ERIC Educational Resources Information Center

    Marshall, James D.

    2004-01-01

    In this paper the author looks at two forms of philosophical argument or critique. These are derived by himself from the work of the late Kantian scholar, Stephan Korner who, in his book "What is Philosophy?" (1969), draws a number of distinctions between different forms of "philosophical" argument or critique. The two forms of derived argument,…

  14. Utilize Vacuum Forming to Make Interdisciplinary Connections

    ERIC Educational Resources Information Center

    Love, Tyler S.; Valenza, Frank

    2011-01-01

    The concept of vacuum forming has been around since the 19th century, despite not being fully utilized in industry until the 1950s. In the past, industrial arts classes have used vacuum-forming projects to concentrate solely on the manufacturing process and the final product. However, vacuum forming is not just an old industrial arts activity; it…

  15. 7 CFR 51.569 - Well formed.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Standards for Celery Definitions § 51.569 Well formed. Well formed means that the branches are fairly... 7 Agriculture 2 2011-01-01 2011-01-01 false Well formed. 51.569 Section 51.569 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections,...

  16. 7 CFR 51.569 - Well formed.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Standards for Celery Definitions § 51.569 Well formed. Well formed means that the branches are fairly... 7 Agriculture 2 2010-01-01 2010-01-01 false Well formed. 51.569 Section 51.569 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections,...

  17. 42 CFR 60.19 - Forms.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Forms. 60.19 Section 60.19 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS HEALTH EDUCATION ASSISTANCE LOAN PROGRAM The Loan § 60.19 Forms. All HEAL forms are approved by the Secretary and may not be changed...

  18. 42 CFR 60.19 - Forms.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Forms. 60.19 Section 60.19 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS HEALTH EDUCATION ASSISTANCE LOAN PROGRAM The Loan § 60.19 Forms. All HEAL forms are approved by the Secretary and may not be changed...

  19. 42 CFR 60.19 - Forms.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Forms. 60.19 Section 60.19 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS HEALTH EDUCATION ASSISTANCE LOAN PROGRAM The Loan § 60.19 Forms. All HEAL forms are approved by the Secretary and may not be changed...

  20. 42 CFR 60.19 - Forms.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Forms. 60.19 Section 60.19 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS HEALTH EDUCATION ASSISTANCE LOAN PROGRAM The Loan § 60.19 Forms. All HEAL forms are approved by the Secretary and may not be changed...

  1. 42 CFR 60.19 - Forms.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Forms. 60.19 Section 60.19 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS HEALTH EDUCATION ASSISTANCE LOAN PROGRAM The Loan § 60.19 Forms. All HEAL forms are approved by the Secretary and may not be changed...

  2. 32 CFR 48.205 - Election form.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 1 2010-07-01 2010-07-01 false Election form. 48.205 Section 48.205 National... SERVICEMAN'S FAMILY PROTECTION PLAN Election of Options § 48.205 Election form. The form for making election after October 31, 1968, is prescribed as Election of Options, Retired Serviceman's Family...

  3. 32 CFR 48.205 - Election form.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 1 2013-07-01 2013-07-01 false Election form. 48.205 Section 48.205 National... SERVICEMAN'S FAMILY PROTECTION PLAN Election of Options § 48.205 Election form. The form for making election after October 31, 1968, is prescribed as Election of Options, Retired Serviceman's Family...

  4. 32 CFR 48.205 - Election form.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 1 2011-07-01 2011-07-01 false Election form. 48.205 Section 48.205 National... SERVICEMAN'S FAMILY PROTECTION PLAN Election of Options § 48.205 Election form. The form for making election after October 31, 1968, is prescribed as Election of Options, Retired Serviceman's Family...

  5. 32 CFR 48.205 - Election form.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 1 2014-07-01 2014-07-01 false Election form. 48.205 Section 48.205 National... SERVICEMAN'S FAMILY PROTECTION PLAN Election of Options § 48.205 Election form. The form for making election after October 31, 1968, is prescribed as Election of Options, Retired Serviceman's Family...

  6. 32 CFR 48.205 - Election form.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 1 2012-07-01 2012-07-01 false Election form. 48.205 Section 48.205 National... SERVICEMAN'S FAMILY PROTECTION PLAN Election of Options § 48.205 Election form. The form for making election after October 31, 1968, is prescribed as Election of Options, Retired Serviceman's Family...

  7. 16 CFR 455.3 - Window form.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Window form. 455.3 Section 455.3 Commercial Practices FEDERAL TRADE COMMISSION TRADE REGULATION RULES USED MOTOR VEHICLE TRADE REGULATION RULE § 455.3 Window form. (a) Form given to buyer. Give the buyer of a used vehicle sold by you the window...

  8. 16 CFR 455.3 - Window form.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 1 2012-01-01 2012-01-01 false Window form. 455.3 Section 455.3 Commercial Practices FEDERAL TRADE COMMISSION TRADE REGULATION RULES USED MOTOR VEHICLE TRADE REGULATION RULE § 455.3 Window form. (a) Form given to buyer. Give the buyer of a used vehicle sold by you the window...

  9. 16 CFR 455.3 - Window form.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 1 2013-01-01 2013-01-01 false Window form. 455.3 Section 455.3 Commercial Practices FEDERAL TRADE COMMISSION TRADE REGULATION RULES USED MOTOR VEHICLE TRADE REGULATION RULE § 455.3 Window form. (a) Form given to buyer. Give the buyer of a used vehicle sold by you the window...

  10. 16 CFR 455.3 - Window form.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 1 2011-01-01 2011-01-01 false Window form. 455.3 Section 455.3 Commercial Practices FEDERAL TRADE COMMISSION TRADE REGULATION RULES USED MOTOR VEHICLE TRADE REGULATION RULE § 455.3 Window form. (a) Form given to buyer. Give the buyer of a used vehicle sold by you the window...

  11. 16 CFR 455.3 - Window form.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 1 2014-01-01 2014-01-01 false Window form. 455.3 Section 455.3 Commercial Practices FEDERAL TRADE COMMISSION TRADE REGULATION RULES USED MOTOR VEHICLE TRADE REGULATION RULE § 455.3 Window form. (a) Form given to buyer. Give the buyer of a used vehicle sold by you the window...

  12. 25 CFR 75.9 - Application form.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Application form. 75.9 Section 75.9 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR TRIBAL GOVERNMENT REVISION OF THE MEMBERSHIP ROLL OF THE EASTERN BAND OF CHEROKEE INDIANS, NORTH CAROLINA § 75.9 Application form. The form of application...

  13. 25 CFR 75.9 - Application form.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Application form. 75.9 Section 75.9 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR TRIBAL GOVERNMENT REVISION OF THE MEMBERSHIP ROLL OF THE EASTERN BAND OF CHEROKEE INDIANS, NORTH CAROLINA § 75.9 Application form. The form of application...

  14. 27 CFR 46.22 - Forms prescribed.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... CIGARETTE PAPERS AND TUBES Administrative Provisions § 46.22 Forms prescribed. (a) The appropriate TTB officer is authorized to prescribe all forms required by this part. You must furnish all of the..., and as required by this part. You must file each form in accordance with its instructions. (b)...

  15. 27 CFR 46.22 - Forms prescribed.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... CIGARETTE PAPERS AND TUBES Administrative Provisions § 46.22 Forms prescribed. (a) The appropriate TTB officer is authorized to prescribe all forms required by this part. You must furnish all of the..., and as required by this part. You must file each form in accordance with its instructions. (b)...

  16. 27 CFR 46.22 - Forms prescribed.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... CIGARETTE PAPERS AND TUBES Administrative Provisions § 46.22 Forms prescribed. (a) The appropriate TTB officer is authorized to prescribe all forms required by this part. You must furnish all of the..., and as required by this part. You must file each form in accordance with its instructions. (b)...

  17. 27 CFR 45.27 - Forms prescribed.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... OF THE TREASURY (CONTINUED) TOBACCO REMOVAL OF TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES.... (a) The appropriate TTB officer is authorized to prescribe all forms required by this part. You must... instructions for the form, and as required by this part. You must file each form in accordance with...

  18. 27 CFR 46.22 - Forms prescribed.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... CIGARETTE PAPERS AND TUBES Administrative Provisions § 46.22 Forms prescribed. (a) The appropriate TTB officer is authorized to prescribe all forms required by this part. You must furnish all of the..., and as required by this part. You must file each form in accordance with its instructions. (b)...

  19. 27 CFR 46.22 - Forms prescribed.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... CIGARETTE PAPERS AND TUBES Administrative Provisions § 46.22 Forms prescribed. (a) The appropriate TTB officer is authorized to prescribe all forms required by this part. You must furnish all of the..., and as required by this part. You must file each form in accordance with its instructions. (b)...

  20. 27 CFR 45.27 - Forms prescribed.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... OF THE TREASURY (CONTINUED) TOBACCO REMOVAL OF TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES.... (a) The appropriate TTB officer is authorized to prescribe all forms required by this part. You must... instructions for the form, and as required by this part. You must file each form in accordance with...

  1. 27 CFR 45.27 - Forms prescribed.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... OF THE TREASURY (CONTINUED) TOBACCO REMOVAL OF TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES.... (a) The appropriate TTB officer is authorized to prescribe all forms required by this part. You must... instructions for the form, and as required by this part. You must file each form in accordance with...

  2. 27 CFR 45.27 - Forms prescribed.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... OF THE TREASURY (CONTINUED) TOBACCO REMOVAL OF TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES.... (a) The appropriate TTB officer is authorized to prescribe all forms required by this part. You must... instructions for the form, and as required by this part. You must file each form in accordance with...

  3. 27 CFR 45.27 - Forms prescribed.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... OF THE TREASURY (CONTINUED) TOBACCO REMOVAL OF TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES.... (a) The appropriate TTB officer is authorized to prescribe all forms required by this part. You must... instructions for the form, and as required by this part. You must file each form in accordance with...

  4. Method of forming composite fiber blends

    NASA Technical Reports Server (NTRS)

    McMahon, Paul E. (Inventor); Chung, Tai-Shung (Inventor); Ying, Lincoln (Inventor)

    1989-01-01

    The instant invention involves a process used in preparing fibrous tows which may be formed into polymeric plastic composites. The process involves the steps of (a) forming a tow of strong filamentary materials; (b) forming a thermoplastic polymeric fiber; (c) intermixing the two tows; and (d) withdrawing the intermixed tow for further use.

  5. 78 FR 57807 - Aged Beneficiary Designation Forms

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-20

    ... record- keeper in regulations on June 13, 1997 (62 FR 32426). All beneficiary designation forms in an...; ] FEDERAL RETIREMENT THRIFT INVESTMENT BOARD 5 CFR Part 1651 Aged Beneficiary Designation Forms AGENCY... beneficiary designation form is valid only if it is received by the TSP record- keeper not more than one...

  6. 25 CFR 153.3 - Application form.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Application form. 153.3 Section 153.3 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER DETERMINATION OF COMPETENCY: CROW INDIANS § 153.3 Application form. The application form shall include, among other things: (a) The name of...

  7. 49 CFR 225.21 - Forms.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... miles, yard switching train miles, and other train miles run during the month. (c) Form FRA 6180.55a... Office of Safety, FRA, 400 Seventh Street, SW., Washington, DC 20590. (a) Form FRA F 6180.54—Rail Equipment Accident/Incident Report. Form FRA F 6180.54 shall be used to report each reportable...

  8. Taking Another Look: Sensuous, Consistent Form.

    ERIC Educational Resources Information Center

    Townley, Mary Ross

    1983-01-01

    There is a natural progression from making single objects to creating sculpture. By modeling the forms of objects like funnels and light bulbs, students become aware of the quality of curves and the edges of angles. Sculptural form in architecture can be understood as consistency in the forms. (CS)

  9. FormEd: An X Window System application for managing first-order formulas

    SciTech Connect

    Henry, T.L.; McCune, W.W.

    1990-11-01

    FormEd is a window-based program for constructing, displaying, and managing first-order logic formulas. The main motivation for constructing FormEd was the desire to have formulas displayed in a readable, two-dimensional format. Users of FormEd can make two kinds of transformation on formulas: logic transformations, such as negation normal form translation, which preserve the meaning of a formula, and edit transformations, which can be used to make arbitrary changes, such as adding a hypothesis to a subformula. FormEd was written by using the X Window System, Version 11, and code from the theorem prover OTTER. 4 refs.

  10. 7 CFR 1280.625 - Certification and referendum form ballot form.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Certification and referendum form ballot form. 1280... LAMB PROMOTION, RESEARCH, AND INFORMATION ORDER Procedures To Request a Referendum Definitions § 1280.625 Certification and referendum form ballot form. Form LS-86 shall be used to vote in the...

  11. 7 CFR 1280.625 - Certification and referendum form ballot form.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Certification and referendum form ballot form. 1280... LAMB PROMOTION, RESEARCH, AND INFORMATION ORDER Procedures To Request a Referendum Definitions § 1280.625 Certification and referendum form ballot form. Form LS-86 shall be used to vote in the...

  12. 76 FR 42129 - Agency Information Collection Activities: Case Submission Form, Case Assistance Form

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-18

    ... SECURITY Agency Information Collection Activities: Case Submission Form, Case Assistance Form (Form DHS-7001), Online Ombudsman Form DHS-7001 AGENCY: Office of the Citizenship and Immigration Service... practices of USCIS to mitigate problems. This form is used by an applicant who is experiencing problems...

  13. 75 FR 41486 - Termination Settlement Proposal Forms-FAR (Standard Forms 1435 Through 1440)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-16

    ... Proposal Forms--FAR (Standard Forms 1435 Through 1440) AGENCY: Department of Defense (DOD), General... Proposal Forms--FAR (Standard Forms 1435 through 1440). Public comments are particularly invited on... technological collection techniques or other forms of information technology. DATES: Submit comments on...

  14. New Forming Technologies for Autobody at POSCO

    NASA Astrophysics Data System (ADS)

    Lee, Hong-Woo; Cha, Myung-Hwan; Choi, Byung-Keun; Kim, Gyo-Sung; Park, Sung-Ho

    2011-08-01

    As development of car body with light weight and enhanced safety became one of the hottest issues in the auto industry, the advanced high strength steels have been broadly applied to various automotive parts over the last few years. Corresponding to this trend, POSCO has developed various types of cold and hot rolled AHSSs such as DP, TRIP, CP and FB, and continues to develop new types of steel in order to satisfy the requirement of OEMs more extensively. To provide optimal technical supports to customers, POSCO has developed more advanced EVI concept, which includes the concept of CE/SE, VA/VE, VI and PP as well as the conventional EVI strategy. To realize this concept, POSCO not only supports customers with material data, process guideline, and evaluation of formability, weld-ability, paint-ability and performance but also provides parts or sub-assemblies which demand highly advanced technologies. Especially, to accelerate adoption of AHSS in autobody, POSCO has tried to come up with optimal solutions to AHSS forming. Application of conventional forming technologies has been restricted more and more by relatively low formability of AHSS with high tensile-strength. To overcome the limitation in the forming, POSCO has recently developed new forming technologies such as hydro-forming, hot press forming, roll forming and form forming. In this paper, tailored strength HPF, hydroformed torsion beam axle and multi-directional roll forming are introduced as examples of new forming technologies.

  15. Performance Test on Polymer Waste Form - 12137

    SciTech Connect

    Lee, Se Yup

    2012-07-01

    Polymer solidification was attempted to produce stable waste form for the boric acid concentrates and the dewatered spent resins. The polymer mixture was directly injected into the mold or drum which was packed with the boric acid concentrates and the dewatered spent resins, respectively. The waste form was produced by entirely curing the polymer mixture. A series of performance tests was conducted including compressive strength test, water immersion test, leach test, thermal stability test, irradiation stability test and biodegradation stability test for the polymer waste forms. From the results of the performance tests for the polymer waste forms, it is believed that the polymer waste form is very stable and can satisfy the acceptance criteria for permanent disposal. At present, performance tests with full scale polymer waste forms are being carried out in order to obtain qualification certificate by the regulatory institute in Korea. Polymer waste forms were prepared with the surrogate of boric acid concentrates and the surrogate of spent ion exchange resins respectively. Waste forms were also made in lab scale and in full scale. Lab. scale waste forms were directly subjected to a series of the performance tests. In the case of full scale waste form, the test specimens for the performance test were taken from a part of waste form by coring. A series of performance tests was conducted including compressive strength test, thermal stability test, irradiation stability test and biodegradation stability test, water immersion test, leach test, and free standing water for the polymer waste forms. In addition, a fire resistance test was performed on the waste forms by the requirement of the regulatory institute in Korea. Every polymer waste forms containing the boric acid concentrates and the spent ion exchange resins had exhibited excellent structural integrity of more than 27.58 MPa (4,000 psi) of compressive strength. On thermal stability testing, biodegradation

  16. Canonical forms of multidimensional steady inviscid flows

    NASA Technical Reports Server (NTRS)

    Taasan, Shlomo

    1993-01-01

    Canonical forms and canonical variables for inviscid flow problems are derived. In these forms the components of the system governed by different types of operators (elliptic and hyperbolic) are separated. Both the incompressible and compressible cases are analyzed, and their similarities and differences are discussed. The canonical forms obtained are block upper triangular operator form in which the elliptic and non-elliptic parts reside in different blocks. The full nonlinear equations are treated without using any linearization process. This form enables a better analysis of the equations as well as better numerical treatment. These forms are the analog of the decomposition of the one dimensional Euler equations into characteristic directions and Riemann invariants.

  17. [Z-form of intraphage DNA].

    PubMed

    Ulanov, B P; Matorina, T I; Bogush, A I; Rumiantsev, Iu M

    2002-01-01

    The bacteriophage lambda gt10 DNA containing an insertion of 20 pairs of GC-bases capable of being arranged as Z-form was cloned. Two independent methodological approaches based on the main properties of Z-form were used to study the shape of the insertion: formation of transition bridges composed of unpaired nucleotides between left-rotating Z-forms and right-rotating B-forms of helix (j-domain) and high immunogenic activity of Z-form. O-beta-diethylaminoethylhydroxyamine (OHA), an analogue of hydroxylamine, is capable of reacting specifically with unpaired cytidines. In this work this modification was used to inhibit the process of restriction at BamH1-site adjacent to (gc)10 insertion, that N-Methyl-bis(2-chloethyl) amine (MBCA) is capable of fixing the Z-form of the insertion in situ. Fixed Z-form is conserved even after DNA has been isolated from bacteriophage, thereby providing an opportunity of its identification by anti-Z-antibodies. It was shown that from 4 to 6% of the total number of insertions are in the Z-form. The hypothesis of significant role of Z-form in the process of packing of DNA molecules in capsid is put forward.

  18. Review on Cold-Formed Steel Connections

    PubMed Central

    Tan, Cher Siang; Mohammad, Shahrin; Md Tahir, Mahmood; Shek, Poi Ngian

    2014-01-01

    The concept of cold-formed light steel framing construction has been widespread after understanding its structural characteristics with massive research works over the years. Connection serves as one of the important elements for light steel framing in order to achieve its structural stability. Compared to hot-rolled steel sections, cold-formed steel connections perform dissimilarity due to the thin-walled behaviour. This paper aims to review current researches on cold-formed steel connections, particularly for screw connections, storage rack connections, welded connections, and bolted connections. The performance of these connections in the design of cold-formed steel structures is discussed. PMID:24688448

  19. Review on cold-formed steel connections.

    PubMed

    Lee, Yeong Huei; Tan, Cher Siang; Mohammad, Shahrin; Tahir, Mahmood Md; Shek, Poi Ngian

    2014-01-01

    The concept of cold-formed light steel framing construction has been widespread after understanding its structural characteristics with massive research works over the years. Connection serves as one of the important elements for light steel framing in order to achieve its structural stability. Compared to hot-rolled steel sections, cold-formed steel connections perform dissimilarity due to the thin-walled behaviour. This paper aims to review current researches on cold-formed steel connections, particularly for screw connections, storage rack connections, welded connections, and bolted connections. The performance of these connections in the design of cold-formed steel structures is discussed.

  20. A canonical form for nonlinear systems

    NASA Technical Reports Server (NTRS)

    Su, R.; Hunt, L. R.

    1986-01-01

    The concepts of transformation and canonical form have been used in analyzing linear systems. These ideas are extended to nonlinear systems. A coordinate system and a corresponding canonical form are developed for general nonlinear control systems. Their usefulness is demonstrated by showing that every feedback linearizable system becomes a system with only feedback paths in the canonical form. For control design involving a nonlinear system, one approach is to put the system in its canonical form and approximate by that part having only feedback paths.

  1. Review on cold-formed steel connections.

    PubMed

    Lee, Yeong Huei; Tan, Cher Siang; Mohammad, Shahrin; Tahir, Mahmood Md; Shek, Poi Ngian

    2014-01-01

    The concept of cold-formed light steel framing construction has been widespread after understanding its structural characteristics with massive research works over the years. Connection serves as one of the important elements for light steel framing in order to achieve its structural stability. Compared to hot-rolled steel sections, cold-formed steel connections perform dissimilarity due to the thin-walled behaviour. This paper aims to review current researches on cold-formed steel connections, particularly for screw connections, storage rack connections, welded connections, and bolted connections. The performance of these connections in the design of cold-formed steel structures is discussed. PMID:24688448

  2. Method for hot press forming articles

    DOEpatents

    Baker, Robert R.; Hartsock, Dale L.

    1982-01-01

    This disclosure relates to an improved method for achieving the best bond strength and for minimizing distortion and cracking of hot pressed articles. In particular, in a method for hot press forming both an outer facing circumferential surface of and an inner portion of a hub, and of bonding that so-formed outer facing circumferential surface to an inner facing circumferential surface of a pre-formed ring thereby to form an article, the following improvement is made. Normally, in this method, the outside ring is restrained by a restraining sleeve of ring-shaped cross-section having an inside diameter. A die member, used to hot press form the hub, is so-formed as to have an outside diameter sized to engage the inside diameter of the restraining sleeve in a manner permitting relative movement therebetween. The improved method is one in which several pairs of matched restraining sleeve and die member are formed with each matched pair having a predetermined diameter. The predetermined diameter of each matched pair is different from another matched pair by stepped increments. The largest inside diameter of a restraining sleeve is equal to the diameter of the outer facing circumferential surface of the hub. Each pair of the matched restraining sleeve and die member is used to form an article in which an inside hub is bonded to an outside ring. The several samples so-formed are evaluated to determine which sample has the best bond formed between the hub and the ring with the least or no cracking or distortion in the ring portion of the article. Thereafter, the matched restraining sleeve and die member which form the article having the best bonding characteristics and least distortion cracking is then used for repeated formations of articles.

  3. 46 CFR 308.548 - Standard form of underwriting agency agreement for cargo, Form MA-318.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Standard form of underwriting agency agreement for cargo, Form MA-318. 308.548 Section 308.548 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... underwriting agency agreement for cargo, Form MA-318. This form, which may be obtained from the American...

  4. 46 CFR 308.548 - Standard form of underwriting agency agreement for cargo, Form MA-318.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 8 2011-10-01 2011-10-01 false Standard form of underwriting agency agreement for cargo, Form MA-318. 308.548 Section 308.548 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... underwriting agency agreement for cargo, Form MA-318. This form, which may be obtained from the American...

  5. 76 FR 36620 - Proposed Collection; Comment Request for Form 8453-F and Form 8879-F

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-22

    ... Internal Revenue Service Proposed Collection; Comment Request for Form 8453-F and Form 8879-F AGENCY... U.S.C. 3506(c)(2)(A)). Currently, the IRS is soliciting comments concerning Form 8453-F, U.S. Estate of Trust Income Tax Declaration and Signature for Electronic and Magnetic Made Filing and Form...

  6. 43 CFR 3440.1-1 - Forms.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Forms. 3440.1-1 Section 3440.1-1 Public... OF THE INTERIOR MINERALS MANAGEMENT (3000) LICENSES TO MINE Licenses to Mine § 3440.1-1 Forms. (a... Bureau of Land Management State Office having jurisdiction over the lands involved (43 CFR subpart...

  7. 12 CFR 905.25 - Forms.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Forms. 905.25 Section 905.25 Banks and Banking... headquarters facility and shall be used for the purpose indicated: Form 10-91—Monthly Survey of Rates and Terms... Home Loan Bank Directors. 9103—Election Ballot, Election of Federal Home Loan Bank Directors....

  8. 27 CFR 25.3 - Forms prescribed.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Forms prescribed. 25.3 Section 25.3 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS BEER Scope of Regulations § 25.3 Forms prescribed. (a) The appropriate...

  9. 20 CFR 703.2 - Forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... substitute forms without OWCP's approval. Form No. Title (1) LS-271 Application for Self-Insurance. (2) LS-274 Report of Injury Experience. (3) LS-275 SI Self-Insurer's Agreement and Undertaking. (4) LS-275 IC Insurance Carrier's Agreement and Undertaking. (5) LS-276 Application for Security Deposit Determination....

  10. 27 CFR 25.3 - Forms prescribed.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Forms prescribed. 25.3 Section 25.3 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS BEER Scope of Regulations § 25.3 Forms prescribed. (a) The appropriate...

  11. 27 CFR 25.3 - Forms prescribed.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Forms prescribed. 25.3 Section 25.3 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL BEER Scope of Regulations § 25.3 Forms prescribed. (a) The appropriate...

  12. 27 CFR 25.3 - Forms prescribed.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Forms prescribed. 25.3 Section 25.3 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL BEER Scope of Regulations § 25.3 Forms prescribed. (a) The appropriate...

  13. Are All Forms of Scholarship Considered Equal?

    ERIC Educational Resources Information Center

    Ward, Chris; Carrigan, Martin

    2009-01-01

    Boyer's four forms of scholarship were detailed in his 1990 book Scholarship Reconsidered: Priorities of the Professoriate. In the 18 years since publication of that book, universities struggle with changing the promotion and tenure criteria to include all four forms of scholarship. Faculty members often focus on publications as they prepare for…

  14. New Form 990 Will Follow Your Functions

    ERIC Educational Resources Information Center

    Hyatt, Thomas K.

    2008-01-01

    Accountability, transparency, and compliance, are three principles which form the bedrock of best practices in nonprofit governance and are at the heart of a lively debate that has unfolded over the past five years. However, most governing board members do not associate the realization of these principles with the task of completing Form 990, the…

  15. 7 CFR 58.729 - Forming containers.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Forming containers. 58.729 Section 58.729 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Procedures § 58.729 Forming containers. Containers either lined or unlined shall be assembled and stored in...

  16. 25 CFR 214.24 - Forms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Forms. 214.24 Section 214.24 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF OSAGE RESERVATION LANDS, OKLAHOMA, FOR MINING, EXCEPT OIL AND GAS § 214.24 Forms. Applications, leases, and other papers must be upon...

  17. 25 CFR 214.24 - Forms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Forms. 214.24 Section 214.24 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF OSAGE RESERVATION LANDS, OKLAHOMA, FOR MINING, EXCEPT OIL AND GAS § 214.24 Forms. Applications, leases, and other papers must be upon...

  18. 48 CFR 908.7115 - Forms.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... be obtained by DOE offices in accordance with the DOE Guide 242.1-1, DOE Forms Management, for use with DOE Order 200.1, Information Management Program. (b) Standard, optional, and certain other agency forms as listed in the GSA Supply Catalog will be obtained by DOE offices in accordance with FPMR 41...

  19. 25 CFR 227.30 - Forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Forms. 227.30 Section 227.30 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF CERTAIN LANDS IN WIND RIVER INDIAN RESERVATION, WYOMING, FOR OIL AND GAS MINING Operations § 227.30 Forms. The provisions of § 211.30 of...

  20. 25 CFR 227.30 - Forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Forms. 227.30 Section 227.30 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF CERTAIN LANDS IN WIND RIVER INDIAN RESERVATION, WYOMING, FOR OIL AND GAS MINING Operations § 227.30 Forms. The provisions of § 211.30 of...

  1. 25 CFR 227.30 - Forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Forms. 227.30 Section 227.30 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF CERTAIN LANDS IN WIND RIVER INDIAN RESERVATION, WYOMING, FOR OIL AND GAS MINING Operations § 227.30 Forms. The provisions of § 211.30 of...

  2. 18 CFR 1308.51 - Form.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 2 2014-04-01 2014-04-01 false Form. 1308.51 Section 1308.51 Conservation of Power and Water Resources TENNESSEE VALLEY AUTHORITY CONTRACT DISPUTES Subpoenas § 1308.51 Form. (a) A subpoena shall state the name of the Board and the title of the...

  3. 18 CFR 1308.51 - Form.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 2 2013-04-01 2012-04-01 true Form. 1308.51 Section 1308.51 Conservation of Power and Water Resources TENNESSEE VALLEY AUTHORITY CONTRACT DISPUTES Subpoenas § 1308.51 Form. (a) A subpoena shall state the name of the Board and the title of the...

  4. 18 CFR 1308.51 - Form.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 2 2012-04-01 2012-04-01 false Form. 1308.51 Section 1308.51 Conservation of Power and Water Resources TENNESSEE VALLEY AUTHORITY CONTRACT DISPUTES Subpoenas § 1308.51 Form. (a) A subpoena shall state the name of the Board and the title of the...

  5. 49 CFR 582.5 - Information form.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 7 2012-10-01 2012-10-01 false Information form. 582.5 Section 582.5... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) INSURANCE COST INFORMATION REGULATION § 582.5 Information form. The information made available pursuant to § 582.4 shall be presented in writing in...

  6. 49 CFR 387.15 - Forms.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... CARRIERS Motor Carriers of Property § 387.15 Forms. Endorsements for policies of insurance (Illustration I.... Endorsements to policies of insurance and surety bonds shall specify that coverage thereunder will remain in... (3/82) Form Approved OMB No. 2125-0074 Endorsement for Motor Carrier Policies of Insurance for...

  7. 49 CFR 387.15 - Forms.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... CARRIERS Motor Carriers of Property § 387.15 Forms. Endorsements for policies of insurance (Illustration I.... Endorsements to policies of insurance and surety bonds shall specify that coverage thereunder will remain in... (3/82) Form Approved OMB No. 2125-0074 Endorsement for Motor Carrier Policies of Insurance for...

  8. 49 CFR 387.15 - Forms.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... CARRIERS Motor Carriers of Property § 387.15 Forms. Endorsements for policies of insurance (Illustration I.... Endorsements to policies of insurance and surety bonds shall specify that coverage thereunder will remain in... (3/82) Form Approved OMB No. 2125-0074 Endorsement for Motor Carrier Policies of Insurance for...

  9. 49 CFR 582.5 - Information form.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 7 2011-10-01 2011-10-01 false Information form. 582.5 Section 582.5 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) INSURANCE COST INFORMATION REGULATION § 582.5 Information form. The information made...

  10. 7 CFR 29.6016 - Form.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Form. 29.6016 Section 29.6016 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Standards Definitions § 29.6016 Form. The stage of preparation of tobacco such as stemmed...

  11. 7 CFR 58.729 - Forming containers.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Forming containers. 58.729 Section 58.729 Agriculture... Procedures § 58.729 Forming containers. Containers either lined or unlined shall be assembled and stored in a sanitary manner to prevent contamination. The handling of containers by filler crews should be done...

  12. 13 CFR 108.100 - Business form.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 13 Business Credit and Assistance 1 2012-01-01 2012-01-01 false Business form. 108.100 Section 108.100 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION NEW MARKETS VENTURE CAPITAL (âNMVCâ) PROGRAM Qualifications for the NMVC Program Organizing A Nmvc Company § 108.100 Business form. A...

  13. 13 CFR 108.100 - Business form.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 13 Business Credit and Assistance 1 2011-01-01 2011-01-01 false Business form. 108.100 Section 108.100 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION NEW MARKETS VENTURE CAPITAL (âNMVCâ) PROGRAM Qualifications for the NMVC Program Organizing A Nmvc Company § 108.100 Business form. A...

  14. 13 CFR 108.100 - Business form.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 13 Business Credit and Assistance 1 2013-01-01 2013-01-01 false Business form. 108.100 Section 108.100 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION NEW MARKETS VENTURE CAPITAL (âNMVCâ) PROGRAM Qualifications for the NMVC Program Organizing A Nmvc Company § 108.100 Business form. A...

  15. 13 CFR 108.100 - Business form.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 13 Business Credit and Assistance 1 2014-01-01 2014-01-01 false Business form. 108.100 Section 108.100 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION NEW MARKETS VENTURE CAPITAL (âNMVCâ) PROGRAM Qualifications for the NMVC Program Organizing A Nmvc Company § 108.100 Business form. A...

  16. 49 CFR 387.15 - Forms.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... CARRIERS Motor Carriers of Property § 387.15 Forms. Endorsements for policies of insurance (Illustration I.... Endorsements to policies of insurance and surety bonds shall specify that coverage thereunder will remain in... (3/82) Form Approved OMB No. 2125-0074 Endorsement for Motor Carrier Policies of Insurance for...

  17. Binary Quadratic Forms: A Historical View

    ERIC Educational Resources Information Center

    Khosravani, Azar N.; Beintema, Mark B.

    2006-01-01

    We present an expository account of the development of the theory of binary quadratic forms. Beginning with the formulation and proof of the Two-Square Theorem, we show how the study of forms of the type x[squared] + ny[squared] led to the discovery of the Quadratic Reciprocity Law, and how this theorem, along with the concept of reduction relates…

  18. 13 CFR 108.100 - Business form.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Business form. 108.100 Section 108.100 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION NEW MARKETS VENTURE CAPITAL (âNMVCâ) PROGRAM Qualifications for the NMVC Program Organizing A Nmvc Company § 108.100 Business form. A...

  19. 27 CFR 25.3 - Forms prescribed.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Forms prescribed. 25.3 Section 25.3 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS BEER Scope of Regulations § 25.3 Forms prescribed. (a) The appropriate...

  20. The Three Forms of Molecular Oxygen.

    ERIC Educational Resources Information Center

    Laing, Michael

    1989-01-01

    Finds that a logical application of the simple rules of the molecular orbital bonding theory for diatomic molecules predicted the existence of three spin isomers of the oxygen molecule: one triplet form with two unpaired electrons and two singlet forms with all electrons paired. (MVL)

  1. Exploring Quality Assurance in Sixth Form Colleges

    ERIC Educational Resources Information Center

    Stoten, David William

    2012-01-01

    Purpose: This paper aims to focus on the changing nature of quality assurance systems within the sixth form college sector. Design/methodology/approach: Ten sixth form colleges were surveyed across England and staff from varying levels within college hierarchies questioned about how quality assurance systems were implemented. Research involved…

  2. ACOUSTIC FORMING FOR ENHANCED DEWATERING AND FORMATION

    SciTech Connect

    Cyrus K Aidun

    2007-11-30

    The next generation of forming elements based on acoustic excitation to increase drainage and enhances formation both with on-line control and profiling capabilities has been investigated in this project. The system can be designed and optimized based on the fundamental experimental and computational analysis and investigation of acoustic waves in a fiber suspension flow and interaction with the forming wire.

  3. Methods for forming long subsurface heaters

    SciTech Connect

    Kim, Dong Sub

    2013-09-17

    A method for forming a longitudinal subsurface heater includes longitudinally welding an electrically conductive sheath of an insulated conductor heater along at least one longitudinal strip of metal. The longitudinal strip is formed into a tubular around the insulated conductor heater with the insulated conductor heater welded along the inside surface of the tubular.

  4. 25 CFR 227.30 - Forms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Forms. 227.30 Section 227.30 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF CERTAIN LANDS IN WIND RIVER INDIAN RESERVATION, WYOMING, FOR OIL AND GAS MINING Operations § 227.30 Forms. The provisions of § 211.30 of...

  5. 25 CFR 227.30 - Forms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Forms. 227.30 Section 227.30 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF CERTAIN LANDS IN WIND RIVER INDIAN RESERVATION, WYOMING, FOR OIL AND GAS MINING Operations § 227.30 Forms. The provisions of § 211.30 of...

  6. Teaching Students to Form Effective Questions

    ERIC Educational Resources Information Center

    Stafford, Tish

    2009-01-01

    The ability to question lies at the heart of human curiosity and is a necessary component of cognition. The author stresses that forming questions is essential to human thought and communication. As such, forming questions is a foundational process that cuts across curricular areas and is embedded in content standards across the nation, including…

  7. Forms of vitality play in infancy.

    PubMed

    Español, Silvia; Martínez, Mauricio; Bordoni, Mariana; Camarasa, Rosario; Carretero, Soledad

    2014-12-01

    In this paper we report a qualitative study based on the constant comparative method to initiate the systematic study of forms of vitality play. This is an unnoticed non-figurative play frame linked to early social play and temporal arts in which child and adult elaborate the dynamics of their own movements and sounds in a repetition-variation form. In the introduction we present the theoretical underpinnings and the sporadic observations we have done in previous studies. Then, by the iterative observations of the recorded material of a longitudinal case study on play during the third year of life, we generated the general category of forms of vitality play and four subcategories of display modes of forms of vitality play (improvised forms of vitality play, ritualized forms of vitality play, forms of vitality play combined with pretend play, and forms of vitality play combined with role playing) which are illustrated with descriptive narratives. We discuss the properties of the developed categories, the limits of the present study, and the need to continue systematizing the research on this playful activity.

  8. 43 CFR 3440.1-1 - Forms.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Forms. 3440.1-1 Section 3440.1-1 Public... OF THE INTERIOR MINERALS MANAGEMENT (3000) LICENSES TO MINE Licenses to Mine § 3440.1-1 Forms. (a... Bureau of Land Management State Office having jurisdiction over the lands involved (43 CFR subpart...

  9. 30 CFR 281.22 - Lease form.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Lease form. 281.22 Section 281.22 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE LEASING OF MINERALS OTHER THAN OIL, GAS, AND SULPHUR IN THE OUTER CONTINENTAL SHELF Leasing Procedures § 281.22 Lease form. The...

  10. 5 CFR 847.303 - Election forms.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Election forms. 847.303 Section 847.303...) ELECTIONS OF RETIREMENT COVERAGE BY CURRENT AND FORMER EMPLOYEES OF NONAPPROPRIATED FUND INSTRUMENTALITIES Procedures for Elections Under the Retroactive Provisions § 847.303 Election forms. (a) Eligible...

  11. 5 CFR 847.303 - Election forms.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Election forms. 847.303 Section 847.303...) ELECTIONS OF RETIREMENT COVERAGE BY CURRENT AND FORMER EMPLOYEES OF NONAPPROPRIATED FUND INSTRUMENTALITIES Procedures for Elections Under the Retroactive Provisions § 847.303 Election forms. (a) Eligible...

  12. 5 CFR 847.303 - Election forms.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false Election forms. 847.303 Section 847.303...) ELECTIONS OF RETIREMENT COVERAGE BY CURRENT AND FORMER EMPLOYEES OF NONAPPROPRIATED FUND INSTRUMENTALITIES Procedures for Elections Under the Retroactive Provisions § 847.303 Election forms. (a) Eligible...

  13. 5 CFR 847.303 - Election forms.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 2 2012-01-01 2012-01-01 false Election forms. 847.303 Section 847.303...) ELECTIONS OF RETIREMENT COVERAGE BY CURRENT AND FORMER EMPLOYEES OF NONAPPROPRIATED FUND INSTRUMENTALITIES Procedures for Elections Under the Retroactive Provisions § 847.303 Election forms. (a) Eligible...

  14. 5 CFR 847.303 - Election forms.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 2 2014-01-01 2014-01-01 false Election forms. 847.303 Section 847.303...) ELECTIONS OF RETIREMENT COVERAGE BY CURRENT AND FORMER EMPLOYEES OF NONAPPROPRIATED FUND INSTRUMENTALITIES Procedures for Elections Under the Retroactive Provisions § 847.303 Election forms. (a) Eligible...

  15. 28 CFR 12.24 - Forms.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Forms. 12.24 Section 12.24 Judicial Administration DEPARTMENT OF JUSTICE REGISTRATION OF CERTAIN PERSONS HAVING KNOWLEDGE OF FOREIGN ESPIONAGE, COUNTERESPIONAGE, OR SABOTAGE MATTERS UNDER THE ACT OF AUGUST 1, 1956 § 12.24 Forms. (a) Every person required...

  16. Formulas in Physics Have a "Standard" Form

    ERIC Educational Resources Information Center

    Moelter, Matthew J.; Jackson, Martin

    2012-01-01

    We discuss the importance of the ordering of symbols in physics formulas and identify implicit conventions that govern the "standard" form for how formulas are written and interpreted. An important part of writing and reading this form is understanding distinctions among constants, parameters, and variables. We delineate these conventions and…

  17. 48 CFR 1332.702-70 - Forms.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Forms. 1332.702-70 Section 1332.702-70 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE GENERAL CONTRACTING... electronic or hardcopy procurement request form on which the availability of adequate funds have...

  18. 27 CFR 4.3 - Forms prescribed.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Forms prescribed. 4.3 Section 4.3 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS LABELING AND ADVERTISING OF WINE Scope § 4.3 Forms prescribed. (a)...

  19. Forms of Address in Chilean Spanish

    ERIC Educational Resources Information Center

    Bishop, Kelley; Michnowicz, Jim

    2010-01-01

    The present investigation examines possible social and linguistic factors that influence forms of address used in Chilean Spanish with various interlocutors. A characteristic of the Spanish of Chile is the use of a variety of forms of address for the second person singular, "tu", "vos", and "usted", with corresponding verb conjugations (Lipski…

  20. 1 CFR 19.1 - Form.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 1 General Provisions 1 2013-01-01 2012-01-01 true Form. 19.1 Section 19.1 General Provisions... ORDERS AND PRESIDENTIAL PROCLAMATIONS § 19.1 Form. Proposed Executive orders and proclamations shall be... Tracts of Land for Use in Executive Orders and Proclamations,”1 prepared by the Bureau of Land...

  1. 1 CFR 19.1 - Form.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 1 General Provisions 1 2012-01-01 2012-01-01 false Form. 19.1 Section 19.1 General Provisions... ORDERS AND PRESIDENTIAL PROCLAMATIONS § 19.1 Form. Proposed Executive orders and proclamations shall be... Tracts of Land for Use in Executive Orders and Proclamations,”1 prepared by the Bureau of Land...

  2. 1 CFR 19.1 - Form.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 1 General Provisions 1 2014-01-01 2012-01-01 true Form. 19.1 Section 19.1 General Provisions... ORDERS AND PRESIDENTIAL PROCLAMATIONS § 19.1 Form. Proposed Executive orders and proclamations shall be... Tracts of Land for Use in Executive Orders and Proclamations,”1 prepared by the Bureau of Land...

  3. 7 CFR 1786.33 - Forms.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... (CONTINUED) PREPAYMENT OF RUS GUARANTEED AND INSURED LOANS TO ELECTRIC AND TELEPHONE BORROWERS Prepayment of RUS Guaranteed Federal Financing Bank Loans Pursuant to Section 306(A) of the RE Act § 1786.33 Forms. Guarantees and loan guarantee agreements executed by RUS pursuant to this subpart will be on forms...

  4. An Analysis of Teacher Evaluation Forms.

    ERIC Educational Resources Information Center

    Ether, Marueen T. Gillick

    Forms used for evaluating teachers from every geographic area to the United States were examined to determine common characteristics. Thirty of 75 forms received from school districts (local educational agencies) were analyzed. A synthesis of evaluation schemes across the country includes certain characteristics: (1) each teacher must have a…

  5. 30 CFR 256.49 - Lease form.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Lease form. 256.49 Section 256.49 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE LEASING OF SULPHUR OR OIL AND GAS IN THE OUTER CONTINENTAL SHELF Issuance of Leases § 256.49 Lease form. Oil and gas leases and...

  6. Short Form of the Developmental Behaviour Checklist

    ERIC Educational Resources Information Center

    Taffe, John R.; Gray, Kylie M.; Einfeld, Stewart L.; Dekker, Marielle C.; Koot, Hans M.; Emerson, Eric; Koskentausta, Terhi; Tonge, Bruce J.

    2007-01-01

    A 24-item short form of the 96-item Developmental Behaviour Checklist was developed to provide a brief measure of Total Behaviour Problem Score for research purposes. The short form Developmental Behaviour Checklist (DBC-P24) was chosen for low bias and high precision from among 100 randomly selected item sets. The DBC-P24 was developed from…

  7. 48 CFR 1846.670-5 - Forms.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Forms. 1846.670-5 Section 1846.670-5 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CONTRACT MANAGEMENT QUALITY ASSURANCE Material Inspection and Receiving Reports 1846.670-5 Forms....

  8. 49 CFR 1177.4 - Sample forms.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 8 2010-10-01 2010-10-01 false Sample forms. 1177.4 Section 1177.4 Transportation... TRANSPORTATION RULES OF PRACTICE RECORDATION OF DOCUMENTS § 1177.4 Sample forms. (a) Sample short summary for the... short summary of the document to appear in the index follows: [a short summary as described in...

  9. Recirculation as a Form of Conservation.

    ERIC Educational Resources Information Center

    Gordon, Jeffrey J.

    1982-01-01

    Discusses nine forms of conservation practices: sustained yield, repair, careful use, greater efficiency, lower consumption, doing without, substitution, new resources, and recycling. Suggests recirculation (saving goods from discard and from being broken down in a new manufacturing stage) as a 10th form of conservation practice. (Author/JN)

  10. Forms of vitality play in infancy.

    PubMed

    Español, Silvia; Martínez, Mauricio; Bordoni, Mariana; Camarasa, Rosario; Carretero, Soledad

    2014-12-01

    In this paper we report a qualitative study based on the constant comparative method to initiate the systematic study of forms of vitality play. This is an unnoticed non-figurative play frame linked to early social play and temporal arts in which child and adult elaborate the dynamics of their own movements and sounds in a repetition-variation form. In the introduction we present the theoretical underpinnings and the sporadic observations we have done in previous studies. Then, by the iterative observations of the recorded material of a longitudinal case study on play during the third year of life, we generated the general category of forms of vitality play and four subcategories of display modes of forms of vitality play (improvised forms of vitality play, ritualized forms of vitality play, forms of vitality play combined with pretend play, and forms of vitality play combined with role playing) which are illustrated with descriptive narratives. We discuss the properties of the developed categories, the limits of the present study, and the need to continue systematizing the research on this playful activity. PMID:24909632

  11. Reinforcement for Stretch Formed Sheet Metal

    NASA Technical Reports Server (NTRS)

    Lea, J. B.; Baxter, C. R.

    1983-01-01

    Tearing of aluminum sheet metal durinng stretch forming prevented by flame spraying layer of aluminum on edges held in stretch-forming machine. Technique improves grip of machine on metal and reinforced sheet better able to with stand concentration of force in vicinity of grips.

  12. Information Technology and New Forms of Organisations.

    ERIC Educational Resources Information Center

    Ghasemiyeh, Rahim; Li, Feng

    This paper evaluates the impacts of the Internet on organizational structures and identifies new forms of organizations in light of information technology (IT) advances. Four traditional forms of organizations are summarized, i.e., the bureaucratic hierarchy, the entrepreneurial organization, the matrix organization, and the adhocacy. The…

  13. Deformation and Forming of Joined Materials

    SciTech Connect

    Carsley, John; Hovanski, Yuri; Clarke, Kester D.; Krajewski, Paul E.

    2014-09-23

    Introductory article to a set of invited papers from the TMS committee on shaping and forming. This paper introduces a set of papers that were prepared to discussing the deformation and forming of joined materials, and to announce an upcoming symposium at the 2015 MS&T meeting in Columbus Ohio.

  14. 1 CFR 19.1 - Form.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 1 General Provisions 1 2010-01-01 2010-01-01 false Form. 19.1 Section 19.1 General Provisions... ORDERS AND PRESIDENTIAL PROCLAMATIONS § 19.1 Form. Proposed Executive orders and proclamations shall be... Tracts of Land for Use in Executive Orders and Proclamations,”1 prepared by the Bureau of Land...

  15. 1 CFR 19.1 - Form.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 1 General Provisions 1 2011-01-01 2011-01-01 false Form. 19.1 Section 19.1 General Provisions... ORDERS AND PRESIDENTIAL PROCLAMATIONS § 19.1 Form. Proposed Executive orders and proclamations shall be... Tracts of Land for Use in Executive Orders and Proclamations,”1 prepared by the Bureau of Land...

  16. 48 CFR 908.7115 - Forms.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... be obtained by DOE offices in accordance with the DOE Guide 242.1-1, DOE Forms Management, for use with DOE Order 200.1, Information Management Program. (b) Standard, optional, and certain other agency forms as listed in the GSA Supply Catalog will be obtained by DOE offices in accordance with FPMR 41...

  17. 48 CFR 908.7115 - Forms.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... be obtained by DOE offices in accordance with the DOE Guide 242.1-1, DOE Forms Management, for use with DOE Order 200.1, Information Management Program. (b) Standard, optional, and certain other agency forms as listed in the GSA Supply Catalog will be obtained by DOE offices in accordance with FPMR 41...

  18. 48 CFR 908.7115 - Forms.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... be obtained by DOE offices in accordance with the DOE Guide 242.1-1, DOE Forms Management, for use with DOE Order 200.1, Information Management Program. (b) Standard, optional, and certain other agency forms as listed in the GSA Supply Catalog will be obtained by DOE offices in accordance with FPMR 41...

  19. Eighteenth-century forms of quasicrystals.

    PubMed

    Pina, Carlos M; López-Acevedo, Victoria

    2016-01-01

    A careful inspection of the drawings and baked clay models created by the mineralogist Romé de L'Isle in the 18th century has revealed the existence of a number of intriguing forms with pentagonal symmetries. These forms cannot be classified in any of the 32 crystal classes. They can thus be considered the first crystallographic descriptions of polyhedral forms found in quasicrystals two centuries later. This paper presents a symmetry analysis of the fascinating drawings and clay models with pentagonal symmetries described in the book Cristallographie published in 1783 by Romé de L'Isle, as well as a comparison with quasicrystals recently synthesized. The paper also briefly discusses what could induce Romé de L'Isle to consider forms with pentagonal symmetries as plausible crystal forms. PMID:26697870

  20. Urban form, health, and the law's limits.

    PubMed

    Buzbee, William W

    2003-09-01

    Urban form, the law, and health are undoubtedly linked. However, nonlegal factors such as 20th-century reliance on the automobile as well as associated governmental actions and private investment choices have greatly influenced urban form, especially urban sprawl. The American system of federalism, with its traditional allocation of land-use legal authority to local governments, and resulting fragmented legal authority over causes and effects of urban sprawl, renders difficult legal efforts to reshape urban form. Legal frameworks and the dynamics and effects of urban sprawl are largely mismatched. Still, existing legal frameworks and modest legal reforms provide means to encourage or at least allow urban forms that are more conducive to health. However, the law will not easily transform urban form and deter urban sprawl.

  1. Method of forming metal hydride films

    NASA Technical Reports Server (NTRS)

    Steinberg, R.; Alger, D. L.; Cooper, D. W. (Inventor)

    1977-01-01

    The substrate to be coated (which may be of metal, glass or the like) is cleaned, both chemically and by off-sputtering in a vacuum chamber. In an ultra-high vacuum system, vapor deposition by a sublimator or vaporizer coats a cooled shroud disposed around the substrate with a thin film of hydride forming metal which getters any contaminant gas molecules. A shutter is then opened to allow hydride forming metal to be deposited as a film or coating on the substrate. After the hydride forming metal coating is formed, deuterium or other hydrogen isotopes are bled into the vacuum system and diffused into the metal film or coating to form a hydride of metal film. Higher substrate temperatures and pressures may be used if various parameters are appropriately adjusted.

  2. Method for forming porous platinum films

    DOEpatents

    Maya, Leon

    2000-01-01

    A method for forming a platinum film includes providing a substrate, sputtering a crystalline platinum oxide layer over at least a portion of the substrate, and reducing the crystalline platinum oxide layer to form the platinum film. A device includes a non-conductive substrate and a platinum layer having a density of between about 2 and 5 g/cm.sup.3 formed over at least a portion of the non-conductive substrate. The platinum films produced in accordance with the present invention provide porous films suitable for use as electrodes, yet require few processing steps. Thus, such films are less costly. Such films may be formed on both conductive and non-conductive substrates. While the invention has been illustrated with platinum, other metals, such as noble metals, that form a low density oxide when reactively sputtered may also be used.

  3. Form factors in the radiative pion decay

    NASA Astrophysics Data System (ADS)

    Mateu, V.; Portolés, J.

    2007-10-01

    We perform an analysis of the form factors that rule the structure-dependent amplitude in radiative pion decay. The resonance contributions to π→eνeγ decays are computed through the proper construction of the vector and axial-vector form factors by setting the QCD driven asymptotic properties of the three-point Green functions and , and by demanding the smoothening of the form factors at high transfer of momentum. A comparison between theoretical and experimental determination of the form factors is also carried out. We also consider and evaluate the role played by a non-standard tensor form factor. We conclude that, at present and due to the hadronic uncertainties, the search for new physics in this process is not feasible.

  4. IMO Fireball report form: results and prospects

    NASA Astrophysics Data System (ADS)

    Hankey, M.; Perlerin, V.

    2015-01-01

    At the 2014 IMC, we presented the new IMO (International Meteor Organization) online, Fireball report (available at fireballs.imo.net). This fireball report form was specifically designed for use by people with no astronomy experience who witnessed a fireball, a bolide or a suspected similar phenomenon. The IMO version of the form has been officially launched in February 2015. Since then, the form has been translated in different languages and customized for organizations around the world. In this paper, we will present preliminary results of the form and provide tips to improve the online presence of local organizations, in order to promote usage. We will also highlight procedures to be followed by local organizations to get a custom version of the form.

  5. Composite materials formed with anchored nanostructures

    DOEpatents

    Seals, Roland D; Menchhofer, Paul A; Howe, Jane Y; Wang, Wei

    2015-03-10

    A method of forming nano-structure composite materials that have a binder material and a nanostructure fiber material is described. A precursor material may be formed using a mixture of at least one metal powder and anchored nanostructure materials. The metal powder mixture may be (a) Ni powder and (b) NiAl powder. The anchored nanostructure materials may comprise (i) NiAl powder as a support material and (ii) carbon nanotubes attached to nanoparticles adjacent to a surface of the support material. The process of forming nano-structure composite materials typically involves sintering the mixture under vacuum in a die. When Ni and NiAl are used in the metal powder mixture Ni.sub.3Al may form as the binder material after sintering. The mixture is sintered until it consolidates to form the nano-structure composite material.

  6. Superplasticity and superplastic forming of ceramics

    SciTech Connect

    Nieh, T.G.; Wadsworth, J.

    1994-05-01

    Recent advances in the basic understanding of superplasticity and superplastic forming of ceramics are reviewed. Deformation mechanisms as well as microstructural requirements for superplastic ceramics are discussed. Microstructural effects, such as grain size, dynamic grain growth, and the presence of grain-boundary liquid phases, on the superplastic properties and deformation behavior of ceramics are addressed. Superplastic forming, and particularly biaxial gas-pressure forming, of several ceramics, including YTZP and Al{sub 2}O{sub 3}/YTZP, is also presented. The forming behavior of these ceramics is correlated with that obtained from conventional uniaxial tests. Examples of concurrent superplastic forming and diffusion bonding (SPF/DB) of metal-ceramic hybrids are given.

  7. Exotic Forms of Silicon for Energy Applications

    NASA Astrophysics Data System (ADS)

    Taylor, P. Craig

    2015-03-01

    Over the last few decades many exotic forms of carbon, such as carbon-60, carbon nanotubes, and graphene, have generated novel scientific discoveries and revolutionized many important applications. Similar potentially transformative breakthroughs may be expected with exotic forms of silicon. Such structures include, but are not necessarily limited to, (1) those formed under high pressure that are metastable at ambient pressure, (2) single layers of Si (silicene), (2) clathrate Si, which has been studied for superconducting and thermoelectric properties but not in any detail for semiconductor applications, (3) nanostructured forms of Si (nanodots and nanowires), including those composed of diamond Si, (4) porous Si, and (5) any other structures that differ in their structural, optical or electronic properties from bulk diamond Si. Silicon is an abundant, non-toxic element around which an advanced technology exists for semiconducting devices based on diamond Si. One of these exotic forms of Si could form the basis for the next revolution in electronics or even opto-electronics, since some forms exhibit direct, or nearly direct, band gaps. Recent results toward producing pure and dopable semiconductors out of Si nanodots imbedded in amorphous matrices and in clathrate Si and clathrate Si-Ge alloys will be discussed. The author acknowledges important collaborations with R. T. Collins, C. A. Koh, L. Krishna, M. Lusk, and P. Stradins. DOE SUNSHOT program, under Contract DE-EE0005326 and by the NSF MRSEC program under Grant DMR-0820518.

  8. Slab edge insulating form system and methods

    DOEpatents

    Lee, Brain E.; Barsun, Stephan K.; Bourne, Richard C.; Hoeschele, Marc A.; Springer, David A.

    2009-10-06

    A method of forming an insulated concrete foundation is provided comprising constructing a foundation frame, the frame comprising an insulating form having an opening, inserting a pocket former into the opening; placing concrete inside the foundation frame; and removing the pocket former after the placed concrete has set, wherein the concrete forms a pocket in the placed concrete that is accessible through the opening. The method may further comprise sealing the opening by placing a sealing plug or sealing material in the opening. A system for forming an insulated concrete foundation is provided comprising a plurality of interconnected insulating forms, the insulating forms having a rigid outer member protecting and encasing an insulating material, and at least one gripping lip extending outwardly from the outer member to provide a pest barrier. At least one insulating form has an opening into which a removable pocket former is inserted. The system may also provide a tension anchor positioned in the pocket former and a tendon connected to the tension anchor.

  9. Quadratic forms of projective spaces over rings

    NASA Astrophysics Data System (ADS)

    Levchuk, V. M.; Starikova, O. A.

    2006-06-01

    In the passage from fields to rings of coefficients quadratic forms with invertible matrices lose their decisive role. It turns out that if all quadratic forms over a ring are diagonalizable, then in effect this is always a local principal ideal ring R with 2\\in R^*. The problem of the construction of a `normal' diagonal form of a quadratic form over a ring R faces obstacles in the case of indices \\vert R^*:R^{*2}\\vert greater than 1. In the case of index 2 this problem has a solution given in Theorem 2.1 for 1+R^{*2}\\subseteq R^{*2} (an extension of the law of inertia for real quadratic forms) and in Theorem 2.2 for 1+R^2 containing an invertible non-square. Under the same conditions on a ring R with nilpotent maximal ideal the number of classes of projectively congruent quadratic forms of the projective space associated with a free R-module of rank n is explicitly calculated (Proposition 3.2). Up to projectivities, the list of forms is presented for the projective plane over R and also (Theorem 3.3) over the local ring F\\lbrack\\lbrack x,y\\rbrack\\rbrack/\\langle x^{2},xy,y^{2}\\rangle with non-principal maximal ideal, where F=2F is a field with an invertible non-square in 1+F^{2} and \\vert F^{*}:F^{*2}\\vert=2. In the latter case the number of classes of non-diagonalizable quadratic forms of rank 0 depends on one's choice of the field F and is not even always finite; all the other forms make up 21 classes.

  10. Functional design specification: NASA form 1510

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The 1510 worksheet used to calculate approved facility project cost estimates is explained. Topics covered include data base considerations, program structure, relationship of the 1510 form to the 1509 form, and functions which the application must perform: WHATIF, TENENTER, TENTYPE, and data base utilities. A sample NASA form 1510 printout and a 1510 data dictionary are presented in the appendices along with the cost adjustment table, the floppy disk index, and methods for generating the calculated values (TENCALC) and for calculating cost adjustment (CONSTADJ). Storage requirements are given.

  11. Low temperature waste form process intensification

    SciTech Connect

    Fox, K. M.; Cozzi, A. D.; Hansen, E. K.; Hill, K. A.

    2015-09-30

    This study successfully demonstrated process intensification of low temperature waste form production. Modifications were made to the dry blend composition to enable a 50% increase in waste concentration, thus allowing for a significant reduction in disposal volume and associated costs. Properties measurements showed that the advanced waste form can be produced using existing equipment and processes. Performance of the waste form was equivalent or better than the current baseline, with approximately double the amount of waste incorporation. The results demonstrate the feasibility of significantly accelerating low level waste immobilization missions across the DOE complex and at environmental remediation sites worldwide.

  12. Form factor and boundary contribution of amplitude

    NASA Astrophysics Data System (ADS)

    Huang, Rijun; Jin, Qingjun; Feng, Bo

    2016-06-01

    The boundary contribution of an amplitude in the BCFW recursion relation can be considered as a form factor involving boundary operator and unshifted particles. At the tree-level, we show that by suitable construction of Lagrangian, one can relate the leading order term of boundary operators to some composite operators of mathcal{N} = 4 superYang-Mills theory, then the computation of form factors is translated to the computation of amplitudes. We compute the form factors of these composite operators through the computation of corresponding double trace amplitudes.

  13. Impaired vitality form recognition in autism.

    PubMed

    Rochat, Magali J; Veroni, Vania; Bruschweiler-Stern, Nadia; Pieraccini, Cinzia; Bonnet-Brilhault, Frédérique; Barthélémy, Catherine; Malvy, Joëlle; Sinigaglia, Corrado; Stern, Daniel N; Rizzolatti, Giacomo

    2013-08-01

    Along with the understanding of the goal of an action ("what" is done) and the intention underlying it ("why" it is done), social interactions largely depend on the appraisal of the action from the dynamics of the movement: "how" it is performed (its "vitality form"). Do individuals with autism, especially children, possess this capacity? Here we show that, unlike typically developing individuals, individuals with autism reveal severe deficits in recognizing vitality forms, and their capacity to appraise them does not improve with age. Deficit in vitality form recognition appears, therefore, to be a newly recognized trait marker of autism.

  14. Superplastic forming using NIKE3D

    SciTech Connect

    Puso, M.

    1996-12-04

    The superplastic forming process requires careful control of strain rates in order to avoid strain localizations. A load scheduler was developed and implemented into the nonlinear finite element code NIKE3D to provide strain rate control during forming simulation and process schedule output. Often the sheets being formed in SPF are very thin such that less expensive membrane elements can be used as opposed to shell elements. A large strain membrane element was implemented into NIKE3D to assist in SPF process modeling.

  15. Plasma formed ion beam projection lithography system

    DOEpatents

    Leung, Ka-Ngo; Lee, Yung-Hee Yvette; Ngo, Vinh; Zahir, Nastaran

    2002-01-01

    A plasma-formed ion-beam projection lithography (IPL) system eliminates the acceleration stage between the ion source and stencil mask of a conventional IPL system. Instead a much thicker mask is used as a beam forming or extraction electrode, positioned next to the plasma in the ion source. Thus the entire beam forming electrode or mask is illuminated uniformly with the source plasma. The extracted beam passes through an acceleration and reduction stage onto the resist coated wafer. Low energy ions, about 30 eV, pass through the mask, minimizing heating, scattering, and sputtering.

  16. [Ashy dermatitis. Comments on 2 clinical forms].

    PubMed

    Carvajal Huerta, L; Uraga Pazmiño, E; Loayza Vivanzo, E; Sabando Sánchez, R; García Atiaga, I; Jeny, E

    1986-01-01

    The typical clinical characteristic of the ashy dermatitis is the fact that in case of light colored skin, the grey colour remains invariable. There is a new clinical form which is called the Brown Cinder Dermatitis which is characterized by a disciplined localization in the center of the face, trunk or upper extremities together with an inexorable change of the grey colour at the beginning to a brown colour at the end on the other it, has be enhanced the existence of the nummular form which is characterized by the existence of many greyish independent spots of circular or oval form mainly at the level of the trunk.

  17. $sup 238$Pu fuel form activities

    SciTech Connect

    Not Available

    1987-06-01

    This report for STYPu Fuel Form Activities has one main section: SRP-PuFF Facility. The SRL portion of this program has been completed. The program status, budget information, and milestone schedules are discussed. The SRP portion of this report summarizes production of STYPuO2 fuel forms for use in radioisotopic thermoelectric generators (RTG's) in the Plutonium Fuel Form (Puff) Facility at the Savannah River Plant. The PuFF Facility has been placed in a production readiness mode of operation pending funding of additional heat source programs.

  18. Methods of forming semiconductor devices and devices formed using such methods

    DOEpatents

    Fox, Robert V; Rodriguez, Rene G; Pak, Joshua

    2013-05-21

    Single source precursors are subjected to carbon dioxide to form particles of material. The carbon dioxide may be in a supercritical state. Single source precursors also may be subjected to supercritical fluids other than supercritical carbon dioxide to form particles of material. The methods may be used to form nanoparticles. In some embodiments, the methods are used to form chalcopyrite materials. Devices such as, for example, semiconductor devices may be fabricated that include such particles. Methods of forming semiconductor devices include subjecting single source precursors to carbon dioxide to form particles of semiconductor material, and establishing electrical contact between the particles and an electrode.

  19. Sartre, Literature, and the Forms of Knowledge.

    ERIC Educational Resources Information Center

    Hyland, John T.

    1978-01-01

    The author reexamines the status of literature as a form of knowledge and offers some suggestions designed to help improve the characterization of literature, against the background of Sartre's writings on the aesthetic enterprise. (Author/SJL)

  20. 7 CFR 56.55 - Forms.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... MARKETING ACT OF 1946 AND THE EGG PRODUCTS INSPECTION ACT (CONTINUED) VOLUNTARY GRADING OF SHELL EGGS Grading of Shell Eggs Grading Certificates § 56.55 Forms. Grading certificates and sampling report...