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Sample records for born subventricular zone

  1. Glioblastoma Multiforme: Relationship to Subventricular Zone and Recurrence

    OpenAIRE

    Kimura, Margareth; Lee, Yeuh; Miller, Ryan; Castillo, Mauricio

    2013-01-01

    Neurogenesis in the adult mammalian brain is active in two areas: the subgranular zone in the dentate gyrus of the hippocampus and the subventricular zone. Cancer stem cells have been isolated from malignant brain tumors and it is widely believed they arise from transformed endogenous stem cells. We sought to determine if the initial location of glioblastoma (GB) as seen on conventional MRI and its relationship to the subventricular zone (SVZ) predicts the pattern of recurrence. We analyzed t...

  2. Neuropeptide y promotes neurogenesis in murine subventricular zone

    DEFF Research Database (Denmark)

    Agasse, Fabienne; Bernardino, Liliana; Christiansen, Søren H;

    2008-01-01

    Stem cells of the subventricular zone (SVZ) represent a reliable source of neurons for cell replacement. Neuropeptide Y (NPY) promotes neurogenesis in the hippocampal subgranular layer and the olfactory epithelium and may be useful for the stimulation of SVZ dynamic in brain repair purposes. We...

  3. Subventricular zone cell migration: lessons from quantitative 2-photon microscopy

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    Rachel eJames

    2011-03-01

    Full Text Available Neuroblasts born in the adult subventricular zone (SVZ migrate long distances in the rostral migratory stream (RMS to the olfactory bulbs where they integrate into circuitry as functional interneurons. As very little was known about the dynamic parameters of SVZ neuroblast migration, we used two-photon time-lapse microscopy to analyze migration in acute slices. This involved analyzing 3-dimensional stacks of images over time and uncovered several novel aspects of SVZ migration: chains remain stable, cells can be immotile for extensive periods, morphology does not necessarily correlate with motility, neuroblasts exhibit local exploratory motility, dorsoventral migration occurs throughout the striatal SVZ and neuroblasts turn at distinctive angles. We investigated these novel findings in the SVZ and RMS from the population to the single cell level. In this review we also discuss some technical considerations when setting up a two-photon microscopic imaging system. Throughout the review we identify several unsolved questions about SVZ neuroblast migration that might be addressed with current or emerging techniques.

  4. Long-term hydrocephalus alters the cytoarchitecture of the adult subventricular zone.

    Science.gov (United States)

    Campos-Ordoñez, Tania; Herranz-Pérez, Vicente; Chaichana, Kaisorn L; Rincon-Torroella, Jordina; Rigamonti, Daniele; García-Verdugo, Jose M; Quiñones-Hinojosa, Alfredo; Gonzalez-Perez, Oscar

    2014-11-01

    Hydrocephalus can develop secondarily to a disturbance in production, flow and/or absorption of cerebrospinal fluid. Experimental models of hydrocephalus, especially subacute and chronic hydrocephalus, are few and limited, and the effects of hydrocephalus on the subventricular zone are unclear. The aim of this study was to analyze the effects of long-term obstructive hydrocephalus on the subventricular zone, which is the neurogenic niche lining the lateral ventricles. We developed a new method to induce hydrocephalus by obstructing the aqueduct of Sylvius in the mouse brain, thus simulating aqueductal stenosis in humans. In 120-day-old rodents (n=18 per group), the degree of ventricular dilatation and cellular composition of the subventricular zone were studied by immunofluorescence and transmission electron microscopy. In adult patients (age>18years), the sizes of the subventricular zone, corpus callosum, and internal capsule were analyzed by magnetic resonance images obtained from patients with and without aqueductal stenosis (n=25 per group). Mice with 60-day hydrocephalus had a reduced number of Ki67+ and doublecortin+cells on immunofluorescence, as well as decreased number of neural progenitors and neuroblasts in the subventricular zone on electron microscopy analysis as compared to non-hydrocephalic mice. Remarkably, a number of extracellular matrix structures (fractones) contacting the ventricular lumen and blood vessels were also observed around the subventricular zone in mice with hydrocephalus. In humans, the widths of the subventricular zone, corpus callosum, and internal capsule in patients with aqueductal stenosis were significantly smaller than age and gender-matched patients without aqueductal stenosis. In summary, supratentorial hydrocephalus reduces the proliferation rate of neural progenitors and modifies the cytoarchitecture and extracellular matrix compounds of the subventricular zone. In humans, this similar process reduces the subventricular

  5. Modulation of subventricular zone oligodendrogenesis: a role for hemopressin?

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    Sara eXapelli

    2014-02-01

    Full Text Available Neural stem cells (NSCs from the subventricular zone (SVZ have been indicated as a source of new oligodendrocytes to use in regenerative medicine for myelin pathologies. Indeed, NSCs are multipotent cells that can self-renew and differentiate into all neural cell types of the central nervous system (CNS. In normal conditions, SVZ cells are poorly oligodendrogenic, nevertheless their oligodendrogenic potential is boosted following demyelination. Importantly, progressive restriction into the oligodendrocyte fate is specified by extrinsic and intrinsic factors, endocannabinoids being one of these factors. Although a role for endocannabinoids in oligodendrogenesis has already been foreseen, selective agonists and antagonists of cannabinoids receptors produce severe adverse side effects. Herein, we show that hemopressin, a modulator of CB1 receptors, increased oligodendroglial differentiation in SVZ neural stem/progenitor cell cultures derived from neonatal mice. The original results presented in this work suggest that hemopressin and derivatives may be of potential interest for the development of future strategies to treat demyelinating diseases.

  6. Pbx1 is required for adult subventricular zone neurogenesis.

    Science.gov (United States)

    Grebbin, Britta Moyo; Hau, Ann-Christin; Groß, Anja; Anders-Maurer, Marie; Schramm, Jasmine; Koss, Matthew; Wille, Christoph; Mittelbronn, Michel; Selleri, Licia; Schulte, Dorothea

    2016-07-01

    TALE-homeodomain proteins function as components of heteromeric complexes that contain one member each of the PBC and MEIS/PREP subclasses. We recently showed that MEIS2 cooperates with the neurogenic transcription factor PAX6 in the control of adult subventricular zone (SVZ) neurogenesis in rodents. Expression of the PBC protein PBX1 in the SVZ has been reported, but its functional role(s) has not been investigated. Using a genetic loss-of-function mouse model, we now show that Pbx1 is an early regulator of SVZ neurogenesis. Targeted deletion of Pbx1 by retroviral transduction of Cre recombinase into Pbx2-deficient SVZ stem and progenitor cells carrying floxed alleles of Pbx1 significantly reduced the production of neurons and increased the generation of oligodendrocytes. Loss of Pbx1 expression in neuronally committed neuroblasts in the rostral migratory stream in a Pbx2 null background, by contrast, severely compromised cell survival. By chromatin immunoprecipitation from endogenous tissues or isolated cells, we further detected PBX1 binding to known regulatory regions of the neuron-specific genes Dcx and Th days or even weeks before the respective genes are expressed during the normal program of SVZ neurogenesis, suggesting that PBX1 might act as a priming factor to mark these genes for subsequent activation. Collectively, our results establish that PBX1 regulates adult neural cell fate determination in a manner beyond that of its heterodimerization partner MEIS2. PMID:27226325

  7. Implications of irradiating the subventricular zone stem cell niche

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    Vivian Capilla-Gonzalez

    2016-03-01

    Full Text Available Radiation therapy is a standard treatment for brain tumor patients. However, it comes with side effects, such as neurological deficits. While likely multi-factorial, the effect may in part be associated with the impact of radiation on the neurogenic niches. In the adult mammalian brain, the neurogenic niches are localized in the subventricular zone (SVZ of the lateral ventricles and the dentate gyrus of the hippocampus, where the neural stem cells (NSCs reside. Several reports showed that radiation produces a drastic decrease in the proliferative capacity of these regions, which is related to functional decline. In particular, radiation to the SVZ led to a reduced long-term olfactory memory and a reduced capacity to respond to brain damage in animal models, as well as compromised tumor outcomes in patients. By contrast, other studies in humans suggested that increased radiation dose to the SVZ may be associated with longer progression-free survival in patients with high-grade glioma. In this review, we summarize the cellular and functional effects of irradiating the SVZ niche. In particular, we review the pros and cons of using radiation during brain tumor treatment, discussing the complex relationship between radiation dose to the SVZ and both tumor control and toxicity.

  8. Implications of irradiating the subventricular zone stem cell niche.

    Science.gov (United States)

    Capilla-Gonzalez, Vivian; Bonsu, Janice M; Redmond, Kristin J; Garcia-Verdugo, Jose Manuel; Quiñones-Hinojosa, Alfredo

    2016-03-01

    Radiation therapy is a standard treatment for brain tumor patients. However, it comes with side effects, such as neurological deficits. While likely multi-factorial, the effect may in part be associated with the impact of radiation on the neurogenic niches. In the adult mammalian brain, the neurogenic niches are localized in the subventricular zone (SVZ) of the lateral ventricles and the dentate gyrus of the hippocampus, where the neural stem cells (NSCs) reside. Several reports showed that radiation produces a drastic decrease in the proliferative capacity of these regions, which is related to functional decline. In particular, radiation to the SVZ led to a reduced long-term olfactory memory and a reduced capacity to respond to brain damage in animal models, as well as compromised tumor outcomes in patients. By contrast, other studies in humans suggested that increased radiation dose to the SVZ may be associated with longer progression-free survival in patients with high-grade glioma. In this review, we summarize the cellular and functional effects of irradiating the SVZ niche. In particular, we review the pros and cons of using radiation during brain tumor treatment, discussing the complex relationship between radiation dose to the SVZ and both tumor control and toxicity.

  9. Neural stem cells, the subventricular zone and radiotherapy: implications for treating glioblastoma.

    Science.gov (United States)

    Smith, Andrew W; Mehta, Minesh P; Wernicke, A Gabriella

    2016-06-01

    Over the past decade, advances in neuroscience have suggested that neural stem cells resident in specific regions of the adult brain may be involved in development of both primary and recurrent glioblastoma. Neurogenesis and malignant transformation occurs in the subventricular zone adjacent to the lateral ventricles. This region holds promise as a potential target for therapeutic intervention with radiotherapy. However, irradiation of a larger brain volume is not without risk, and significant side effects have been observed. The current literature remains contradictory regarding the efficacy of deliberate intervention with radiation to the subventricular zone. This critical review discusses the connection between neural stem cells and development of glioblastoma, explores the behavior of tumors associated with the subventricular zone, summarizes the discordant literature with respect to the effects of irradiation, and reviews other targeted therapies to this intriguing region. PMID:27108274

  10. The path from the choroid plexus to the subventricular zone: go with the flow!

    Directory of Open Access Journals (Sweden)

    Ana Mendanha Falcao

    2012-08-01

    Full Text Available In adult mammals, under physiological conditions, neurogenesis, the process of generating new functional neurons from precursor cells, occurs mainly in two brain areas: the subgranular zone in the dentate gyrus of the hippocampus, and the subventricular zone (SVZ lining the walls of the brain lateral ventricles. Taking into account the location of the SVZ and the cytoarchitecture of this periventricular neural progenitor cell niche, namely the fact that the slow dividing primary progenitor cells (type B cells of the SVZ extend an apical primary cilium towards the brain ventricular space which is filled with cerebrospinal fluid (CSF, it becomes likely that the composition of the CSF can modulate both self-renewal, proliferation and differentiation of SVZ neural stem cells. The major site of CSF synthesis is the choroid plexus (CP; quite surprisingly, however, it is still largely unknown the contribution of molecules specifically secreted by the adult CP as modulators of the SVZ adult neurogenesis. This is even more relevant in light of recent evidence showing the ability of the CP to adapt its transcriptome and secretome to various physiologic and pathologic stimuli. By giving particular emphasizes to growth factors and axonal guidance molecules we will illustrate how CP-born molecules might play an important role in the SVZ niche cell population dynamics.

  11. Dopaminergic innervation of the human subventricular zone: a comparison between Huntington’s chorea and Parkinson’s disease

    OpenAIRE

    Parent, Martin; Bédard, C; Pourcher, E

    2013-01-01

    The subventricular zone retains its neurogenic capacity throughout life and, as such, is often considered a potential source for endogenous repair in neurodegenerative disorders. Because dopamine is believed to stimulate adult neurogenesis, we looked for possible variations in the dopaminergic innervation of the subventricular zone between cases of Huntington’s chorea and Parkinson’s diseases. Antibodies against tyrosine hydroxylase (TH) and proliferating cell nuclear antigen (PCNA) were used...

  12. Stem cell associated gene expression in glioblastoma multiforme: relationship to survival and the subventricular zone

    OpenAIRE

    Kappadakunnel, Melanie; Eskin, Ascia; DONG, JUN; Nelson, Stanley F.; Mischel, Paul S.; Liau, Linda M.; Ngheimphu, Phioanh; Lai, Albert; Cloughesy, Timothy F.; Goldin, Jonathan; Pope, Whitney B.

    2009-01-01

    Current therapies for glioblastoma (GBM) target bulk tumor through measures such as resection and radiotherapy. However, recent evidence suggests that targeting a subset of tumor cells, so-called cancer stem cells, may be critical for inhibiting tumor growth and relapse. The subventricular zone (SVZ), which lines the ventricles of the brain, is thought to be the origin for the majority of neural stem cells and potentially cancer stem cells. Therefore, we assessed the relationship between tumo...

  13. A Model of Ischemia-Induced Neuroblast Activation in the Adult Subventricular Zone

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    Vergni, Davide; Castiglione, Filippo; Briani, Maya; Middei, Silvia; Alberdi, Elena; Reymann, Klaus G.; Natalini, Roberto; Volonté, Cinzia; Matute, Carlos; Cavaliere, Fabio

    2009-01-01

    We have developed a rat brain organotypic culture model, in which tissue slices contain cortex-subventricular zone-striatum regions, to model neuroblast activity in response to in vitro ischemia. Neuroblast activation has been described in terms of two main parameters, proliferation and migration from the subventricular zone into the injured cortex. We observed distinct phases of neuroblast activation as is known to occur after in vivo ischemia. Thus, immediately after oxygen/glucose deprivation (6–24 hours), neuroblasts reduce their proliferative and migratory activity, whereas, at longer time points after the insult (2 to 5 days), they start to proliferate and migrate into the damaged cortex. Antagonism of ionotropic receptors for extracellular ATP during and after the insult unmasks an early activation of neuroblasts in the subventricular zone, which responded with a rapid and intense migration of neuroblasts into the damaged cortex (within 24 hours). The process is further enhanced by elevating the production of the chemoattractant SDf-1α and may also be boosted by blocking the activation of microglia. This organotypic model which we have developed is an excellent in vitro system to study neurogenesis after ischemia and other neurodegenerative diseases. Its application has revealed a SOS response to oxygen/glucose deprivation, which is inhibited by unfavorable conditions due to the ischemic environment. Finally, experimental quantifications have allowed us to elaborate a mathematical model to describe neuroblast activation and to develop a computer simulation which should have promising applications for the screening of drug candidates for novel therapies of ischemia-related pathologies. PMID:19390597

  14. A model of ischemia-induced neuroblast activation in the adult subventricular zone.

    Directory of Open Access Journals (Sweden)

    Davide Vergni

    Full Text Available We have developed a rat brain organotypic culture model, in which tissue slices contain cortex-subventricular zone-striatum regions, to model neuroblast activity in response to in vitro ischemia. Neuroblast activation has been described in terms of two main parameters, proliferation and migration from the subventricular zone into the injured cortex. We observed distinct phases of neuroblast activation as is known to occur after in vivo ischemia. Thus, immediately after oxygen/glucose deprivation (6-24 hours, neuroblasts reduce their proliferative and migratory activity, whereas, at longer time points after the insult (2 to 5 days, they start to proliferate and migrate into the damaged cortex. Antagonism of ionotropic receptors for extracellular ATP during and after the insult unmasks an early activation of neuroblasts in the subventricular zone, which responded with a rapid and intense migration of neuroblasts into the damaged cortex (within 24 hours. The process is further enhanced by elevating the production of the chemoattractant SDf-1alpha and may also be boosted by blocking the activation of microglia. This organotypic model which we have developed is an excellent in vitro system to study neurogenesis after ischemia and other neurodegenerative diseases. Its application has revealed a SOS response to oxygen/glucose deprivation, which is inhibited by unfavorable conditions due to the ischemic environment. Finally, experimental quantifications have allowed us to elaborate a mathematical model to describe neuroblast activation and to develop a computer simulation which should have promising applications for the screening of drug candidates for novel therapies of ischemia-related pathologies.

  15. Neural progenitor cells isolated from the subventricular zone present hemichannel activity and form functional gap junctions with glial cells

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    Rocío eTalaverón

    2015-10-01

    Full Text Available The postnatal subventricular zone lining the walls of the lateral ventricles contains neural progenitor cells (NPCs that generate new olfactory bulb interneurons. Communication via gap junctions between cells in the subventricular zone is involved in NPC proliferation and in neuroblast migration towards the olfactory bulb. Subventricular zone NPCs can be expanded in vitro in the form of neurospheres that can be used for transplantation purposes after brain injury. We have previously reported that neurosphere-derived NPCs form heterocellular gap junctions with host glial cells when they are implanted after mechanical injury. To analyze functionality of NPC-glial cell gap junctions we performed dye coupling experiments in co-cultures of subventricular zone NPCs with astrocytes or microglia. Neurosphere-derived cells expressed mRNA for at least the hemichannel/gap junction channel proteins connexin 26 (Cx26, Cx43, Cx45 and pannexin 1. Dye coupling experiments revealed that gap junctional communication occurred among neurosphere cells (incidence of coupling: 100%. Moreover, hemichannel activity was also detected in neurosphere cells as evaluated in time-lapse measurements of ethidium bromide uptake. Heterocellular coupling between NPCs and glial cells was evidenced in co-cultures of neurospheres with astrocytes (incidence of coupling: 91.0 ± 4.7% or with microglia (incidence of coupling: 71.9 ± 6.7%. Dye coupling in neurospheres and in co-cultures was inhibited by octanol, a gap junction blocker. Altogether, these results suggest the existence of functional hemichannels and gap junction channels in postnatal subventricular zone neurospheres. In addition, they demonstrate that subventricular zone-derived NPCs can establish functional gap junctions with astrocytes or microglia. Therefore, cell-cell communication via gap junctions and hemichannels with host glial cells might subserve a role in the functional integration of NPCs after implantation in

  16. Roles of Wnt Signaling in the Neurogenic Niche of the Adult Mouse Ventricular-Subventricular Zone.

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    Hirota, Yuki; Sawada, Masato; Huang, Shih-Hui; Ogino, Takashi; Ohata, Shinya; Kubo, Akiharu; Sawamoto, Kazunobu

    2016-02-01

    In many animal species, the production of new neurons (neurogenesis) occurs throughout life, in a specialized germinal region called the ventricular-subventricular zone (V-SVZ). In this region, neural stem cells undergo self-renewal and generate neural progenitor cells and new neurons. In the olfactory system, the new neurons migrate rostrally toward the olfactory bulb, where they differentiate into mature interneurons. V-SVZ-derived new neurons can also migrate toward sites of brain injury, where they contribute to neural regeneration. Recent studies indicate that two major branches of the Wnt signaling pathway, the Wnt/β-catenin and Wnt/planar cell polarity pathways, play essential roles in various facets of adult neurogenesis. Here, we review the Wnt signaling-mediated regulation of adult neurogenesis in the V-SVZ under physiological and pathological conditions. PMID:26572545

  17. Traumatic Brain Injury Activation of the Adult Subventricular Zone Neurogenic Niche

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    Chang, Eun Hyuk; Adorjan, Istvan; Mundim, Mayara V.; Sun, Bin; Dizon, Maria L. V.; Szele, Francis G.

    2016-01-01

    Traumatic brain injury (TBI) is common in both civilian and military life, placing a large burden on survivors and society. However, with the recognition of neural stem cells in adult mammals, including humans, came the possibility to harness these cells for repair of damaged brain, whereas previously this was thought to be impossible. In this review, we focus on the rodent adult subventricular zone (SVZ), an important neurogenic niche within the mature brain in which neural stem cells continue to reside. We review how the SVZ is perturbed following various animal TBI models with regards to cell proliferation, emigration, survival, and differentiation, and we review specific molecules involved in these processes. Together, this information suggests next steps in attempting to translate knowledge from TBI animal models into human therapies for TBI. PMID:27531972

  18. RAE-1 is expressed in the adult subventricular zone and controls cell proliferation of neurospheres

    DEFF Research Database (Denmark)

    Popa, Natalia; Cédile, Oriane; Pollet-Villard, Xavier;

    2011-01-01

    Improving and controlling the capacity of endogenous or grafted adult neural stem cells to repair the nervous system relies on a better knowledge of interactions between immune cells and neural stem cells. Class I major histocompatibility complex (MHC) family members comprise numerous proteins......, and we demonstrate they persist in one of the main area of adult neurogenesis, the subventricular zone (SVZ). So far, RAE-1 is only known for its immune functions as a ligand of the activating receptor NKG2D expressed by natural killer (NK) cells, natural killer T, Tγδ, and some T CD8 lymphocytes. Here......, we do not detect any NKG2D expression in the SVZ either in physiological or in pathological conditions. Interestingly, inhibition of RAE-1 expression in neurosphere cells reduces cell proliferation without alteration of cell viability, which argues for a nonimmune role for RAE-1. These results reveal...

  19. Subventricular zone-derived neuroblasts use vasculature as a scaffold to migrate radially to the cortex in neonatal mice.

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    Le Magueresse, Corentin; Alfonso, Julieta; Bark, Christine; Eliava, Marina; Khrulev, Sergey; Monyer, Hannah

    2012-10-01

    Neurons continue to be generated in the subventricular zone (SVZ) throughout postnatal development and adulthood in rodents. Whereas in adults, virtually all neuroblasts migrate tangentially to the olfactory bulb via the rostral migratory stream (RMS), in neonates, a substantial fraction migrate radially through the corpus callosum (CC) to the cortex. Mechanisms of radial cortical migration have remained unknown. We investigated this by taking recourse to enhanced green fluorescent protein (EGFP)-labeled neuroblasts in the CC and deep cortical layers of neonatal mice and found that they are frequently located adjacent to vasculature. Using time-lapse 2-photon microscopy in acute brain slices, we demonstrate that EGFP-labeled neuroblasts migrate along blood vessels. Although in close proximity to blood vessels, migrating neuroblasts are separated from endothelial cells by 1-2 layers of astrocytic processes, as revealed by electron microscopal studies of retrovirally labeled postnatally born cells. We propose that 2 factors could contribute to the decline of radial migration to the cortex during postnatal development, namely the establishment of a glial sheath delineating the RMS and a gradual decrease in the density of blood vessels in the CC. Together, our data provide evidence for a new mode of radial cortical migration of SVZ-generated neurons involving vasculature and astrocytes.

  20. Aberrant Adult Neurogenesis in the Subventricular Zone-Rostral Migratory Stream-Olfactory Bulb System Following Subchronic Manganese Exposure.

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    Fu, Sherleen; Jiang, Wendy; Gao, Xiang; Zeng, Andrew; Cholger, Daniel; Cannon, Jason; Chen, Jinhui; Zheng, Wei

    2016-04-01

    Adult neurogenesis occurs in brain subventricular zone (SVZ). Our recent data reveal an elevated proliferation of BrdU(+) cells in SVZ following subchronic manganese (Mn) exposure in rats. This study was designed to distinguish Mn effect on the critical stage of adult neurogenesis, ie, proliferation, migration, survival and differentiation from the SVZ via the rostral migratory stream to the olfactory bulb (OB). Adult rats received a single ip-dose of BrdU at the end of 4-week Mn exposure to label proliferating cells. Immunostaining and cell-counting showed a 48% increase of BrdU(+) cells in Mn-exposed SVZ than in controls (Padult rats received 3 daily ip-injections of BrdU followed by subchronic Mn exposure. By 4-week post BrdU labeling, most of the surviving BrdU(+) cells in the OB were differentiated into NeuN(+) matured neurons. However, survival rates of BrdU/NeuN/DAPI triple-labeled cells in OB were 33% and 64% in Mn-exposed and control animals, respectively (Padult SVZ. In the OB, however, Mn exposure significantly reduces the surviving adult-born cells and markedly inhibits their differentiation into mature neurons, resulting in an overall decreased adult neurogenesis in the OB. PMID:26794142

  1. Imaging and recording subventricular zone progenitor cells in live tissue of postnatal mice

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    Benjamin Lacar

    2010-07-01

    Full Text Available The subventricular zone (SVZ is one of two regions where neurogenesis persists in the postnatal brain. The SVZ, located along the lateral ventricle, is the largest neurogenic zone in the brain that contains multiple cell populations including astrocyte-like cells and neuroblasts. Neuroblasts migrate in chains to the olfactory bulb where they differentiate into interneurons. Here, we discuss the experimental approaches to record the electrophysiology of these cells and image their migration and calcium activity in acute slices. Although these techniques were in place for studying glial cells and neurons in mature networks, the SVZ raises new challenges due to the unique properties of SVZ cells, the cellular diversity, and the architecture of the region. We emphasize different methods, such as the use of transgenic mice and in vivo electroporation that permit identification of the different SVZ cell populations for patch clamp recording or imaging. Electroporation also permits genetic labeling of cells using fluorescent reporter mice and modification of the system using either RNA interference technology or floxed mice. In this review, we aim to provide conceptual and technical details of the approaches to perform electrophysiological and imaging studies of SVZ cells.

  2. Notch1 Signaling Modulates Neuronal Progenitor Activity in the Subventricular Zone in Response to Aging and Focal Ischemia

    OpenAIRE

    Sun, Fen; Mao, XiaoOu; Xie, Lin; Ding, Meiping; Shao, Bei; Jin, Kunlin

    2013-01-01

    Neurogenesis diminishes with aging and ischemia-induced neurogenesis also occurs, but reduced in aged brain. Currently, the cellular and molecular pathways mediating these effects remain largely unknown. Our previous study has shown that Notch1 signaling regulates neurogenesis in subventricular zone (SVZ) of young-adult brain after focal ischemia, but whether a similar effect occurs in aged normal and ischemic animals is unknown. Here, we used normal and ischemic aged rat br...

  3. The Association of Subventricular Zone Involvement at Recurrence with Survival after Repeat Surgery in Patients with Recurrent Glioblastoma

    OpenAIRE

    Sonoda, Yukihiko; Saito, Ryuta; Kanamori, Masayuki; Kumabe, Toshihiro; UENOHARA, Hiroshi; TOMINAGA, Teiji

    2013-01-01

    Surgical resection is identified as an important prognostic factor for survival in patients undergoing initial resection of glioblastoma (GBM). However, in patients with tumor recurrence, the benefits of repeat surgery remain unclear. Recent reports have stated that the association between initial surgery for GBM and subventricular zone (SVZ) influences survival. The current study examined the relationship of SVZ involvement in recurrent GBM to survival time after reoperation. We conducted a ...

  4. Inflammation-induced subventricular zone dysfunction leads to olfactory deficits in a targeted mouse model of multiple sclerosis.

    OpenAIRE

    Tepavčević, Vanja; Lazarini, Françoise; Alfaro-Cervello, Clara; Kerninon, Christophe; Yoshikawa, Kazuaki; Garcia-Verdugo, José Manuel; Lledo, Pierre-Marie; Nait-Oumesmar, Brahim; Baron-Van Evercooren, Anne

    2011-01-01

    International audience Neural stem cells (NSCs) persist in defined brain niches, including the subventricular zone (SVZ), throughout adulthood and generate new neurons destined to support specific neurological functions. Whether brain diseases such as multiple sclerosis (MS) are associated with changes in adult NSCs and whether this might contribute to the development and/or persistence of neurological deficits remains poorly investigated. We examined SVZ function in mice in which we targe...

  5. Chromatin-based epigenetics of adult subventricular zone neural stem cells

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    Gabriel eGonzales-Roybal

    2013-10-01

    Full Text Available In specific regions of the adult mammalian brain, neural stem cells (NSCs generate new neurons throughout life. Emerging evidence indicate that chromatin-based transcriptional regulation is a key epigenetic mechanism for the life-long function of adult NSCs. In the adult mouse brain, NSCs in the subventricular zone (SVZ retain the ability to produce both neurons and glia for the life of the animal. In this review, we discuss the origin and function of SVZ NSCs as they relate to key epigenetic concepts of development and potential underlying mechanism of chromatin-based transcriptional regulation. A central point of discussion is how SVZ NSCs – which possess many characteristics of mature, non-neurogenic astrocytes – maintain a youthful ability to produce both neuronal and glial lineages. In addition to reviewing data regarding the function of chromatin-modifying factors in SVZ neurogenesis, we incorporate our growing understanding that long noncoding RNAs (lncRNAs serve as an important element to chromatin-based transcriptional regulation, including that of SVZ NSCs. Discoveries regarding the epigenetic mechanisms of adult SVZ NSCs may provide key insights into fundamental principles of adult stem cell biology as well as the more complex and dynamic developmental environment of the embryonic brain.

  6. Changes in neural stem cells in the subventricular zone in a rat model of communicating hydrocephalus.

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    Li, Yan; Wu, Dongxue; Wu, Chunming; Qu, Zhenyun; Zhao, Yongshun; Li, Weihua; Wang, Jian; Li, Zhongmin

    2014-08-22

    Communicating hydrocephalus is a common type of hydrocephalus. At present, the prevalent treatment is to perform a ventriculo-peritoneal shunt, which, for reasons that are not clear, is sometimes ineffective. The subventricular zone (SVZ) of the lateral ventricles has been established as the primary site of adult neurogenesis. Following cerebral ischemia or brain injury, neural stem cells (NSCs) increase in the SVZ and can both differentiate into neurons and glial cells and respond to the injury. Neural stem cells, enabled by a complex repertoire of factors that precisely regulate the activation, proliferation, differentiation and integration of newborn cells, continuously generate new neurons. However, only a few systematic studies of the role of NSCs in hydrocephalus have been reported. In a rat model of communicating hydrocephalus, we recently showed that hydrocephalus caused the ventricular system to expand over time. We found that the number of NSCs in the SVZ peaked rapidly after hydrocephalus was established and decreased gradually over time until the cells disappeared. NSCs may be involved in the pathophysiology changes and repair process of hydrocephalus.

  7. NMDA modulates oligodendrocyte differentiation of subventricular zone cells through PKC activation

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    Fabio eCavaliere

    2013-12-01

    Full Text Available Multipotent cells from the juvenile subventricular zone (SVZ possess the ability to differentiate into new neural cells. Depending on local signals, SVZ can generate new neurons, astrocytes or oligodendrocytes. We previously demonstrated that activation of NMDA receptors in SVZ progenitors increases the rate of oligodendrocyte differentiation. Here we investigated the mechanisms involved in NMDA receptor-dependent differentiation. Using functional studies performed with the reporter gene luciferase we found that activation of NMDA receptor stimulates PKC. In turn, stimulation of PKC precedes the activation of NADPH oxidase (NOX as demonstrated by translocation of the p67phox subunit to the cellular membrane. We propose that NOX2 is involved in the transduction of the signal from NMDA receptors through PKC activation as the inhibitor gp91 reduced their pro-differentiation effect. In addition, our data and that from other groups suggest that signaling through the NMDA receptor/PKC/NOX2 cascade generates ROS that activate the PI3/mTOR pathway and finally leads to the generation of new oligodendrocytes.

  8. The Adult Ventricular-Subventricular Zone (V-SVZ) and Olfactory Bulb (OB) Neurogenesis.

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    Lim, Daniel A; Alvarez-Buylla, Arturo

    2016-05-02

    A large population of neural stem/precursor cells (NSCs) persists in the ventricular-subventricular zone (V-SVZ) located in the walls of the lateral brain ventricles. V-SVZ NSCs produce large numbers of neuroblasts that migrate a long distance into the olfactory bulb (OB) where they differentiate into local circuit interneurons. Here, we review a broad range of discoveries that have emerged from studies of postnatal V-SVZ neurogenesis: the identification of NSCs as a subpopulation of astroglial cells, the neurogenic lineage, new mechanisms of neuronal migration, and molecular regulators of precursor cell proliferation and migration. It has also become evident that V-SVZ NSCs are regionally heterogeneous, with NSCs located in different regions of the ventricle wall generating distinct OB interneuron subtypes. Insights into the developmental origins and molecular mechanisms that underlie the regional specification of V-SVZ NSCs have also begun to emerge. Other recent studies have revealed new cell-intrinsic molecular mechanisms that enable lifelong neurogenesis in the V-SVZ. Finally, we discuss intriguing differences between the rodent V-SVZ and the corresponding human brain region. The rapidly expanding cellular and molecular knowledge of V-SVZ NSC biology provides key insights into postnatal neural development, the origin of brain tumors, and may inform the development regenerative therapies from cultured and endogenous human neural precursors.

  9. The Adult Ventricular-Subventricular Zone (V-SVZ) and Olfactory Bulb (OB) Neurogenesis.

    Science.gov (United States)

    Lim, Daniel A; Alvarez-Buylla, Arturo

    2016-01-01

    A large population of neural stem/precursor cells (NSCs) persists in the ventricular-subventricular zone (V-SVZ) located in the walls of the lateral brain ventricles. V-SVZ NSCs produce large numbers of neuroblasts that migrate a long distance into the olfactory bulb (OB) where they differentiate into local circuit interneurons. Here, we review a broad range of discoveries that have emerged from studies of postnatal V-SVZ neurogenesis: the identification of NSCs as a subpopulation of astroglial cells, the neurogenic lineage, new mechanisms of neuronal migration, and molecular regulators of precursor cell proliferation and migration. It has also become evident that V-SVZ NSCs are regionally heterogeneous, with NSCs located in different regions of the ventricle wall generating distinct OB interneuron subtypes. Insights into the developmental origins and molecular mechanisms that underlie the regional specification of V-SVZ NSCs have also begun to emerge. Other recent studies have revealed new cell-intrinsic molecular mechanisms that enable lifelong neurogenesis in the V-SVZ. Finally, we discuss intriguing differences between the rodent V-SVZ and the corresponding human brain region. The rapidly expanding cellular and molecular knowledge of V-SVZ NSC biology provides key insights into postnatal neural development, the origin of brain tumors, and may inform the development regenerative therapies from cultured and endogenous human neural precursors. PMID:27048191

  10. Neurotoxic effects of ochratoxin A on the subventricular zone of adult mouse brain.

    Science.gov (United States)

    Paradells, Sara; Rocamonde, Brenda; Llinares, Cristina; Herranz-Pérez, Vicente; Jimenez, Misericordia; Garcia-Verdugo, Jose Manuel; Zipancic, Ivan; Soria, Jose Miguel; Garcia-Esparza, Ma Angeles

    2015-07-01

    Ochratoxin A (OTA), a mycotoxin that was discovered as a secondary metabolite of the fungal species Aspergillus and Penicillium, is a common contaminant in food and animal feed. This mycotoxin has been described as teratogenic, carcinogenic, genotoxic, immunotoxic and has been proven a potent neurotoxin. Other authors have previously reported the effects of OTA in different structures of the central nervous system as well as in some neurogenic regions. However, the impact of OTA exposure in the subventricular zone (SVZ) has not been assessed yet. To elucidate whether OTA affects neural precursors of the mouse SVZ we investigated, in vitro and in vivo, the effects of OTA exposure on the SVZ and on the neural precursors obtained from this neurogenic niche. In this work, we prove the cumulative effect of OTA exposure on proliferation, differentiation and depletion of neural stem cells cultured from the SVZ. In addition, we corroborated these results in vivo by immunohistochemistry and electron microscopy. As a result, we found a significant alteration in the proliferation process, which was evidenced by a decrease in the number of 5-bromo-2-deoxyuridine-positive cells and glial cells, as well as, a significant decrease in the number of neuroblasts in the SVZ. To summarize, in this study we demonstrate how OTA could be a threat to the developing and the adult SVZ through its impact in cell viability, proliferation and differentiation in a dose-dependent manner.

  11. Experiment study of single low dose irradiation on subventricular zone cell

    International Nuclear Information System (INIS)

    Objective: To study the effects of whole brain irradiation on subventricular zone cells (SVZ) in juvenile rat. Methods: Six-week-old Wistar rats, whose brains are still growing, were irradiated with single dose of 1 Gy X-ray. Their body and brain weight were measured at days 30 or 60 after irradiation. The chronological changes of the SVZ were examined at 6 h, days 7, 14, 30 or 60 after irradiation by immunohistochemistry specifically to observe the neural stem cell using anti-nestin antibodies specific for these cells. Results: The rate of brain weight gain of irradiated rats significantly decreased in comparison to controls, although that of body weight gain was similar among them. Multiple apoptotic cell appeared in the SVZ at 6 h after irradiation with simultaneous reduction in nestin-positive cell (69% of the control). The cell levels recovered within a week, with the nestin-positive cells reaching maximal (180%) on day 14, returned to baseline levels within 30 days (96%) and remained unchanged for subsequent 60 days. Conclusions: Single low-dose X-ray administration reversibly affected the levels of neural stem cells in the SVZ region. The result suggest that continuous multiple administration of X-ray in clinical treatment may induce irreversible changes on neural stem cells, and cause brain growth retardation or dysfunction. (authors)

  12. Neurotoxic effects of ochratoxin A on the subventricular zone of adult mouse brain.

    Science.gov (United States)

    Paradells, Sara; Rocamonde, Brenda; Llinares, Cristina; Herranz-Pérez, Vicente; Jimenez, Misericordia; Garcia-Verdugo, Jose Manuel; Zipancic, Ivan; Soria, Jose Miguel; Garcia-Esparza, Ma Angeles

    2015-07-01

    Ochratoxin A (OTA), a mycotoxin that was discovered as a secondary metabolite of the fungal species Aspergillus and Penicillium, is a common contaminant in food and animal feed. This mycotoxin has been described as teratogenic, carcinogenic, genotoxic, immunotoxic and has been proven a potent neurotoxin. Other authors have previously reported the effects of OTA in different structures of the central nervous system as well as in some neurogenic regions. However, the impact of OTA exposure in the subventricular zone (SVZ) has not been assessed yet. To elucidate whether OTA affects neural precursors of the mouse SVZ we investigated, in vitro and in vivo, the effects of OTA exposure on the SVZ and on the neural precursors obtained from this neurogenic niche. In this work, we prove the cumulative effect of OTA exposure on proliferation, differentiation and depletion of neural stem cells cultured from the SVZ. In addition, we corroborated these results in vivo by immunohistochemistry and electron microscopy. As a result, we found a significant alteration in the proliferation process, which was evidenced by a decrease in the number of 5-bromo-2-deoxyuridine-positive cells and glial cells, as well as, a significant decrease in the number of neuroblasts in the SVZ. To summarize, in this study we demonstrate how OTA could be a threat to the developing and the adult SVZ through its impact in cell viability, proliferation and differentiation in a dose-dependent manner. PMID:25256750

  13. New insights into the role of histamine in subventricular zone-olfactory bulb neurogenesis.

    Directory of Open Access Journals (Sweden)

    Maria Francisca eEiriz

    2014-06-01

    Full Text Available The subventricular zone (SVZ contains neural stem cells (NSCs that generate new neurons throughout life. Many brain diseases stimulate NSCs proliferation, neuronal differentiation and homing of these newborns cells into damaged regions. However, complete cell replacement has never been fully achieved. Hence, the identification of proneurogenic factors crucial for stem cell-based therapies will have an impact in brain repair. Histamine, a neurotransmitter and immune mediator, has been recently described to modulate proliferation and commitment of NSCs. Histamine levels are increased in the brain parenchyma and at the cerebrospinal fluid (CSF upon inflammation and brain injury, thus being able to modulate neurogenesis. Herein, we add new data showing that in vivo administration of histamine in the lateral ventricles has a potent proneurogenic effect, increasing the production of new neuroblasts in the SVZ that ultimately reach the olfactory bulb (OB. This report emphasizes the multidimensional effects of histamine in the modulation of NSCs dynamics and sheds light into the promising therapeutic role of histamine for brain regenerative medicine.

  14. Anatomical Involvement of the Subventricular Zone Predicts Poor Survival Outcome in Low-Grade Astrocytomas.

    Directory of Open Access Journals (Sweden)

    Shuai Liu

    Full Text Available The subventricular zone (SVZ has been implicated in the origination, development, and biological behavior of gliomas. Tumor-SVZ contact is also postulated to be a poor prognostic factor in glioblastomas. We aimed to evaluate the prognostic consequence of the anatomical involvement of low-grade gliomas with the SVZ. To that end, we reviewed 143 patients with diffuse astrocytomas, and tumor lesions were manually delineated on magnetic resonance images. We initially investigated the prognostic role of SVZ contact in all patients. Additionally, we investigated the influence of the anatomical proximity of the tumor lesion centroids to the SVZ in the SVZ-involved patient cohorts, as well as location within the SVZ. We found SVZ contact with tumors to be a significant prognostic factor of overall survival in all patients with diffuse astrocytomas (p = 0.027. In the SVZ-involved cohort, a shorter distance from the tumor centroid to the SVZ (≤30 mm correlated with shorter overall survival (p = 0.022 on univariate analysis. However, there was no significant difference in overall survival with respect to the SVZ region involved with the tumor (p = 0.930. Multivariate analysis showed that a shorter distance between the tumor centroid and the SVZ (p = 0.039 was significantly associated with poor overall survival in SVZ-involved patients. Hence, this study helps establish the prognostic role of the anatomical interaction of tumors with the SVZ in low-grade astrocytomas.

  15. PDGF-responsive progenitors persist in the subventricular zone across the lifespan

    Directory of Open Access Journals (Sweden)

    Lisamarie Moore

    2014-02-01

    Full Text Available The SVZ (subventricular zone contains neural stem cells and progenitors of various potentialities. Although initially parsed into A, B, and C cells, this germinal zone is comprised of a significantly more diverse population of cells. Here, we characterized a subset of postnatal PRPs (PDGF-AA-responsive precursors that express functional PDGFα and β receptors from birth to adulthood. When grown in PDGF-AA, dissociated neonatal rat SVZ cells divided to produce non-adherent clusters of progeny. Unlike the self-renewing EGF/FGF-2-responsive precursors that produce neurospheres, these PRPs failed to self-renew after three passages; therefore, we refer to the colonies they produce as spheroids. Upon differentiation these spheroids could produce neurons, type 1 astrocytes and oligodendrocytes. When maintained in medium supplemented with BMP-4 they also produced type 2 astrocytes. Using lineage tracing methods, it became evident that there were multiple types of PRPs, including a subset that could produce neurons, oligodendrocytes, and type 1 and type 2 astrocytes; thus some of these PRPs represent a unique population of precursors that are quatropotential. Spheroids also could be generated from the newborn neocortex and they had the same potentiality as those from the SVZ. By contrast, the adult neocortex produced less than 20% of the numbers of spheroids than the adult SVZ and spheroids from the adult neocortex only differentiated into glial cells. Interestingly, SVZ spheroid producing capacity diminished only slightly from birth to adulthood. Altogether these data demonstrate that there are PRPs that persist in the SVZ that includes a unique population of quatropotential PRPs.

  16. Characterization of Seeding Conditions for Studies on Differentiation Patterns of Subventricular Zone Derived Neurospheres.

    Science.gov (United States)

    Sanchez-Mendoza, Eduardo H; Schlechter, Jana; Hermann, Dirk M; Doeppner, Thorsten R

    2016-01-01

    Stem cell research depends on extensive in vitro research. Poly-D-lysine (PDL) and polyornithine (PornT) are chemically synthesized amino acid chains promoting cell adhesion to solid substrates. Although, PDL and PornT are extensively used, there is no common agreement regarding the most optimal substance and its concentration. We therefore aimed at testing the effect of increasing concentrations (10, 50, and 100 μg/ml) for each compound and their corresponding mixtures (5+5 and 10+10 μg/ml) on the differentiation patterns of subventricular zone derived neurospheres. The latter were cultured for 24 h for protein and morphological analysis or for 8 h for migration analysis. No significant differences were found between increasing concentrations of PDL and PornT alone and the 10+10 condition in Western blots and immunocytochemistry. However, the mixed condition of 5+5 showed decreased glial fibrillary acidic protein and nestin expression with no changes in Akt, pAkt, GSK-3-beta, and pGSK-3-beta expression patterns. The various coating conditions also had no influence on migration of cells emerging from the neurosphere. Nevertheless, stimulation with recombinant human Erythropoietin (rhEpo) reduced migration by 20% regardless of the coating condition. We therefore conclude that a minimal concentration of 10 μg/ml of either compound should be used to produce reliable results with no alterations in protein levels as found for the 5+5 groups, and that the coating has no effect on the response of cells to chemical interventions. As such, a concentration of 10 μg/ml for either substance is sufficient when studying cellular processes of neurospheres in an in vitro or ex vivo environment. PMID:27013970

  17. Characterization of seeding conditions for studies on differentiation patterns of subventricular zone derived neurospheres

    Directory of Open Access Journals (Sweden)

    Eduardo H Sanchez-Mendoza

    2016-03-01

    Full Text Available Stem cell research depends on extensive in vitro research. Poly-D-Lysine (PDL and Polyornithine (PornT are chemically synthesized amino acid chains promoting cell adhesion to solid substrates. Although PDL and PornT are extensively used, there is no common agreement regarding the most optimal substance and its concentration. We therefore aimed at testing the effect of increasing concentrations (10, 50 and 100 µg/ml for each compound and their corresponding mixtures (5+5 and 10+10 µg/ml on the differentiation patterns of subventricular zone derived neurospheres. The latter were cultured for 24 h for protein and morphological analysis or for 8h for migration analysis. No significant differences were found between increasing concentrations of PDL and PornT alone and the 10+10 condition in Western blots and immunocytochemistry. However, the mixed condition of 5+5 showed decreased GFAP and nestin expression with no changes in Akt, pAkt, GSK-3-beta and pGSK-3-beta expression patterns. The various coating conditions also had no influence on migration of cells emerging from the neurosphere. Nevertheless, stimulation with recombinant human Erythropoietin (rhEpo reduced migration by 20% regardless of the coating condition. We therefore conclude that a minimal concentration of 10 µg/ml of either compound should be used to produce reliable results with no alterations in protein levels as found for the 5+5 group, and that the coating has no effect on the response of cells to chemical interventions. As such, a concentration of 10 µg/ml for either substance is sufficient when studying cellular processes of neurospheres in an in vitro or ex vivo environment.

  18. Prenatal cocaine exposure alters progenitor cell markers in the subventricular zone of the adult rat brain

    Science.gov (United States)

    Patel, Dhyanesh Arvind; Booze, Rosemarie M.; Mactutus, Charles F.

    2013-01-01

    Long-term consequences of early developmental exposure to drugs of abuse may have deleterious effects on the proliferative plasticity of the brain. The purpose of this study was to examine the long-term effects of prenatal exposure to cocaine, using the IV route of administration and doses that mimic the peak arterial levels of cocaine use in humans, on the proliferative cell types of the subventricular zones (SVZ) in the adult (180 days-old) rat brain. Employing immunocytochemistry, the expression of GFAP+ (type B cells) and nestin+(GFAP−) (Type C and A cells) staining was quantified in the subcallosal area of the SVZ. GFAP+ expression was significantly different between the prenatal cocaine treated group and the vehicle (saline) control group. The prenatal cocaine treated group possessed significantly lower GFAP+ expression relative to the vehicle control group, suggesting that prenatal cocaine exposure significantly reduced the expression of type B neural stem cells of the SVZ. In addition, there was a significant sex difference in nestin+ expression with females showing approximately 8–13% higher nestin+ expression compared to the males. More importantly, a significant prenatal treatment condition (prenatal cocaine, control) by sex interaction in nestin+ expression was confirmed, indicating different effects of cocaine based on sex of the animal. Specifically, prenatal cocaine exposure eliminated the basal difference between the sexes. Collectively, the present findings suggest that prenatal exposure to cocaine, when delivered via a protocol designed to capture prominent features of recreational usage, can selectively alter the major proliferative cell types in the subcallosal area of the SVZ in an adult rat brain, and does so differently for males and females. PMID:22119286

  19. Identification and culture of neural stem cells isolated from adult rat subventricular zone following fluid percussion brain injury

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Objective To analyze proliferation and differentiation of glial fibrillary acid protein(GFAP)-and nestin-positive(GFAP+/nestin+)cells isolated from the subventricular zone following fluid percussion brain injury to determine whether GFAP+/nestin+ cells exhibit characteristics of neural stem cells.Methods Male Sprague-Dawley rats,aged 12 weeks and weighing 200-250 g,were randomly and evenly assigned to normal control group and model group.In the model group,a rat model of fluid percussion brain injury was es...

  20. Carbon nanotubes impregnated with subventricular zone neural progenitor cells promotes recovery from stroke

    Directory of Open Access Journals (Sweden)

    Moon SU

    2012-06-01

    Full Text Available Sung Ung Moon,1,* Jihee Kim,1,2,* Kiran Kumar Bokara,1,* Jong Youl Kim,1 Dongwoo Khang,3,4 Thomas J Webster,3,4 Jong Eun Lee1,21Department of Anatomy, 2Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea; 3School of Engineering, 4Department of Orthopedics, Brown University, Providence, RI, USA*These authors contributed equally to this workAbstract: The present in vivo study was conducted to evaluate whether hydrophilic (HL or hydrophobic (HP carbon nanotubes (CNTs impregnated with subventricular zone neural progenitor cells (SVZ NPCs could repair damaged neural tissue following stroke. For this purpose, stroke damaged rats were transplanted with HL CNT-SVZ NPCs, HP CNT-SVZ NPCs, or SVZ NPCs alone for 1, 3, 5, and 8 weeks. Results showed that the HP CNT-SVZ NPC transplants improved rat behavior and reduced infarct cyst volume and infarct cyst area compared with the experimental control and the HL CNT-SVZ NPC and SVZ NPCs alone groups. The transplantation groups showed an increase in the expression of nestin (cell stemness marker and proliferation which was evident with the increased number of doublecortin and bromodeoxyuridine double-stained immunopositive cells around the lesion site. But, these effects were more prominent in the HP CNT-SVZ NPC group compared with the other transplantation groups. The HP CNT-SVZ NPC and HL CNT-SVZ NPC transplants increased the number of microtubule-associated protein 2 (marker for neurons and decreased the number of glial fibrillary acidic protein (marker for astroglial cells positive cells within the injury epicenter. The majority of the transplanted HP CNT-SVZ NPCs collectively broadened around the ischemic injured region and the SVZ NPCs differentiated into mature neurons, attained the synapse morphology (TUJ1, synaptophysin, and decreased microglial activation (CD11b/c [OX-42]. For these reasons, this study provided the first evidence that CNTs can improve

  1. Subcellular distribution of N-methyl-D-aspartic acid receptor subunit 1 in neural stem cells within subventricular zone of adult rats

    Institute of Scientific and Technical Information of China (English)

    Zhining Li; Wenlong Lü; Hongyan Dong; Hongbin Fan; Ruiguo Dong; Tiejun Xu

    2011-01-01

    The subcellular localization of N-methyl-D-aspartic acid receptor subunit 1 in neural stem cells of the subventricular zone of adult rats was detected using electron microscopy, following immunohistochemistry and immunogold-silver double staining. Results confirmed the presence of neural stem cells in the subventricular zone, which is a key neurogenic region in the central nervous system of adult mammals. The expression of N-methyl-D-aspartic acid receptor subunit 1 was higher than that of nestin and mainly distributed in the cell membrane, cytoplasm, rough endoplasmic reticulum and Golgi complex of neural stem cells.

  2. Reduced proliferation in the adult mouse subventricular zone increases survival of olfactory bulb interneurons.

    Directory of Open Access Journals (Sweden)

    Yi Sui

    Full Text Available Neurogenesis in the adult brain is largely restricted to the subependymal zone (SVZ of the lateral ventricle, olfactory bulb (OB and the dentate subgranular zone, and survival of adult-born cells in the OB is influenced by factors including sensory experience. We examined, in mice, whether survival of adult-born cells is also regulated by the rate of precursor proliferation in the SVZ. Precursor proliferation was decreased by depleting the SVZ of dopamine after lesioning dopamine neurons in the substantia nigra compacta with 6-hydroxydopamine. Subsequently, we examined the effect of reduced SVZ proliferation on the generation, migration and survival of neuroblasts and mature adult-born cells in the SVZ, rostral migratory stream (RMS and OB. Proliferating cells in the SVZ, measured by 5-bromo-2-deoxyuridine (BrdU injected 2 hours prior to death or by immunoreactivity against Ki67, were reduced by 47% or 36%, respectively, 7 days after dopamine depletion, and by 29% or 31% 42 days after dopamine depletion, compared to sham-treated animals. Neuroblast generation in the SVZ and their migration along the RMS were not affected, neither 7 nor 42 days after the 6-hydroxydopamine injection, since the number of doublecortin-immunoreactive neuroblasts in the SVZ and RMS, as well as the number of neuronal nuclei-immunoreactive cells in the OB, were stable compared to control. However, survival analysis 15 days after 6-hydroxydopamine and 6 days after BrdU injections showed that the number of BrdU+ cells in the SVZ was 70% higher. Also, 42 days after 6-hydroxydopamine and 30 days after BrdU injections, we found an 82% increase in co-labeled BrdU+/γ-aminobutyric acid-immunoreactive cell bodies in the granular cell layer, while double-labeled BrdU+/tyrosine hydroxylase-immunoreactive cell bodies in the glomerular layer increased by 148%. We conclude that the number of OB interneurons following reduced SVZ proliferation is maintained through an increased

  3. Isolation of neural progenitor cells from the human adult subventricular zone based on expression of the cell surface marker CD271

    NARCIS (Netherlands)

    M.E. van Strien; J.A. Sluijs; B.A. Reynolds; D.A. Steindler; E. Aronica; E.M. Hol

    2014-01-01

    Neural progenitor cells (NPCs) in the subventricular zone (SVZ) hold promise for future therapy for neurodegenerative disorders, because the stimulation of adult neurogenesis could potentially restore the function of degenerating neurons and glia. To obtain more knowledge on these NPCs, we developed

  4. A restricted period for formation of outer subventricular zone defined by Cdh1 and Trnp1 levels.

    Science.gov (United States)

    Martínez-Martínez, Maria Ángeles; De Juan Romero, Camino; Fernández, Virginia; Cárdenas, Adrián; Götz, Magdalena; Borrell, Víctor

    2016-06-06

    The outer subventricular zone (OSVZ) is a germinal layer playing key roles in the development of the neocortex, with particular relevance in gyrencephalic species such as human and ferret, where it contains abundant basal radial glia cells (bRGCs) that promote cortical expansion. Here we identify a brief period in ferret embryonic development when apical RGCs generate a burst of bRGCs that become founders of the OSVZ. After this period, bRGCs in the OSVZ proliferate and self-renew exclusively locally, thereby forming a self-sustained lineage independent from the other germinal layers. The time window for the brief period of OSVZ bRGC production is delineated by the coincident downregulation of Cdh1 and Trnp1, and their upregulation reduces bRGC production and prevents OSVZ seeding. This mechanism in cortical development may have key relevance in brain evolution and disease.

  5. Epidermal growth factor treatment of the adult brain subventricular zone leads to focal microglia/macrophage accumulation and angiogenesis.

    Science.gov (United States)

    Lindberg, Olle R; Brederlau, Anke; Kuhn, H Georg

    2014-04-01

    One of the major components of the subventricular zone (SVZ) neurogenic niche is the specialized vasculature. The SVZ vasculature is thought to be important in regulating progenitor cell proliferation and migration. Epidermal growth factor (EGF) is a mitogen with a wide range of effects. When stem and progenitor cells in the rat SVZ are treated with EGF, using intracerebroventricular infusion, dysplastic polyps are formed. Upon extended infusion, blood vessels are recruited into the polyps. In the current study we demonstrate how polyps develop through distinct stages leading up to angiogenesis. As polyps progress, microglia/macrophages accumulate in the polyp core concurrent with increasing cell death. Both microglia/macrophage accumulation and cell death peak during angiogenesis and subsequently decline following polyp vascularization. This model of inducible angiogenesis in the SVZ neurogenic niche suggests involvement of microglia/macrophages in acquired angiogenesis and can be used in detail to study angiogenesis in the adult brain.

  6. Altered speeds and trajectories of neurons migrating in the ventricular and subventricular zones of the reeler neocortex.

    Science.gov (United States)

    Britto, Joanne M; Tait, Karen J; Johnston, Leigh A; Hammond, Vicki E; Kalloniatis, Michael; Tan, Seong-Seng

    2011-05-01

    The Reelin signaling pathway is essential for proper cortical development, but it is unclear to whether Reelin function is primarily important for cortical layering or neuron migration. It has been proposed that Reelin is perhaps required only for somal translocation but not glial-dependent locomotion. This implies that the location of neurons responding to Reelin is restricted to the outer regions of the cortical plate (CP). To determine whether Reelin is required for migration outside of the CP, we used time-lapse imaging to track the behavior of cells undergoing locomotion in the germinal zones. We focused on the migratory activity in the ventricular/subventricular zones where the first transition of bipolar to multipolar migration occurs and where functional Reelin receptors are known to be expressed. Despite Reelin loss, neurons had no difficulty in undergoing radial migration and indeed displayed greater migratory speed. Additionally, compared with the wild-type, reeler neurons displayed altered trajectories with greater deviation from a radial path. These results suggest that Reelin loss has early consequences for migration in the germinal zones that are portrayed as defective radial trajectories and migratory speeds. Together, these abnormalities can give rise to the increased cell dispersion observed in the reeler cortex. PMID:20847150

  7. Hyperbaric oxygen treatment promotes neural stem cell proliferation in the subventricular zone of neonatal rats with hypoxic-ischemic brain damage

    Institute of Scientific and Technical Information of China (English)

    Zhichun Feng; Jing Liu; Rong Ju

    2013-01-01

    Hyperbaric oxygen therapy for the treatment of neonatal hypoxic-ischemic brain damage has been used clinically for many years, but its effectiveness remains controversial. In addition, the mechanism of this potential neuroprotective effect remains unclear. This study aimed to investigate the influence of hyperbaric oxygen on the proliferation of neural stem cells in the subventricular zone of neonatal Sprague-Dawley rats (7 days old) subjected to hypoxic-ischemic brain damage. Six hours after modeling, rats were treated with hyperbaric oxygen once daily for 7 days. Immunohistochemistry revealed that the number of 5-bromo-2′-deoxyuridine positive and nestin positive cells in the subventricular zone of neonatal rats increased at day 3 after hypoxic-ischemic brain damage and peaked at day 5. After hyperbaric oxygen treatment, the number of 5-bromo-2′- deoxyuridine positive and nestin positive cells began to increase at day 1, and was significantly higher than that in normal rats and model rats until day 21. Hematoxylin-eosin staining showed that hyperbaric oxygen treatment could attenuate pathological changes to brain tissue in neonatal rats, and reduce the number of degenerating and necrotic nerve cells. Our experimental findings indicate that hyperbaric oxygen treatment enhances the proliferation of neural stem cells in the subventricular zone of neonatal rats with hypoxic-ischemic brain damage, and has therapeutic potential for promoting neurological recovery following brain injury.

  8. Epidermal Growth Factor Treatment of the Adult Brain Subventricular Zone Leads to Focal Microglia/Macrophage Accumulation and Angiogenesis

    Directory of Open Access Journals (Sweden)

    Olle R. Lindberg

    2014-04-01

    Full Text Available One of the major components of the subventricular zone (SVZ neurogenic niche is the specialized vasculature. The SVZ vasculature is thought to be important in regulating progenitor cell proliferation and migration. Epidermal growth factor (EGF is a mitogen with a wide range of effects. When stem and progenitor cells in the rat SVZ are treated with EGF, using intracerebroventricular infusion, dysplastic polyps are formed. Upon extended infusion, blood vessels are recruited into the polyps. In the current study we demonstrate how polyps develop through distinct stages leading up to angiogenesis. As polyps progress, microglia/macrophages accumulate in the polyp core concurrent with increasing cell death. Both microglia/macrophage accumulation and cell death peak during angiogenesis and subsequently decline following polyp vascularization. This model of inducible angiogenesis in the SVZ neurogenic niche suggests involvement of microglia/macrophages in acquired angiogenesis and can be used in detail to study angiogenesis in the adult brain.

  9. Changes of evoked potential and expression of nestin in subventricular zones in rats after focal cerebral ischemia

    Institute of Scientific and Technical Information of China (English)

    GAO Jie; WANG Yong-tang; WANG Li-li; ZENG Ling; WU Ya-min; SHAO Yang

    2007-01-01

    Objective:To study the characteristics of latency of somatosensory evoked potential (SEP)and motor evoked potential (MEP) and the expression of nestin in subventricular zones (SVZ) after persistent focal cerebral ischemia in rats. Methods: The model of cerebral ischemia in rats was made by middle cerebral artery occlusion (MCAO). All animals of ischemia were sacrificed after 12 h, 1 d, 3 d, 7 d,and 14 d to observe the changes of latency of SEP and MEP and to detect the expression of nestin, with an immunohistochemical approach. Results: The latencies of P1 (positive wave 1), N1 (negative wave 1) and P2 (positive wave 2) in SEP were significantly prolonged after MCAO. The latencies of N1 and N2 waves in MEP were postponed gradually and no statistical difference of latency of N1 wave was found in rats at 7d and 14 d after MCAO. The expression of nestin increased at 12 h, and showed a significant augmentation at 3 d and peaked at 7 d, then declined slightly at 14 d after MCAO. Conclusion: The cerebral ischemia prolonged the latency of EP waves and the expression of nestin was up-regulated and reached the peak at 7d, showing the ischemia induced the proliferation of nervous stem cells. The SEP and MEP may evaluate the proliferation in SVZ after brain ischemia.

  10. Severe instead of mild hyperglycemia inhibits neurogenesis in the subventricular zone of adult rats after transient focal cerebral ischemia.

    Science.gov (United States)

    Tan, S; Zhi, P K; Luo, Z K; Shi, J

    2015-09-10

    Accumulated evidence suggests that enhanced neurogenesis stimulated by ischemic injury contributes to stroke outcome. However, it is unclear whether hyperglycemia, which is frequently tested positive in patients with acute ischemic stroke, influences stroke-induced neurogenesis. The aim of the present study is to examine the effect of hyperglycemia on stroke-induced neurogenesis in a rat model of transient focal cerebral ischemia. For this purpose, adult male Sprague-Dawley rats (220-250 g) were subjected to 90 min of middle cerebral artery occlusion (MCAO). Glucose was administered during ischemia to produce target blood levels ranging from 4.83 ± 0.94 mM (normoglycemia) to 20.76 ± 1.56 mM. To label proliferating cells in ischemic ipsilateral subventricular zone (SVZ) of lateral ventricles, 5'-bromo-2'-deoxyuridine (BrdU) was injected 24h after MCAO. Brains were harvested 2h post-BrdU to evaluate the effects of hyperglycemia on infarct volume and SVZ cell proliferation. Rats that were severely hyperglycemic (19.26 ± 1.48 mM to 20.76 ± 1.56 mM) during ischemia had 24.26% increase in infarct volume (Phyperglycemia (9.43 ± 1.39-10.13 ± 1.24 mM). Our findings indicate that severe instead of mild hyperglycemia exacerbates ischemic injury and inhibits stroke-induced SVZ neurogenesis by a mechanism involving suppression of CREB and BDNF signaling.

  11. Identification and characterization of neuroblasts in the subventricular zone and rostral migratory stream of the adult human brain

    Institute of Scientific and Technical Information of China (English)

    Congmin Wang; Qiangqiang Zhang; Yue Zhang; Rui Chen; Hongjun Song; Zhengang Yang; Fang Liu; Ying-Ying Liu; Cai-Hong Zhao; Yan You; Lei Wang; Jingxiao Zhang; Bin Wei; Tong Ma

    2011-01-01

    It is of great interest to identify new neurons in the adult human brain,but the persistence of neurogenesis in the subventricular zone (SVZ) and the existence of the rostral migratory stream (RMS)-like pathway in the adult human forebrain remain highly controversial.In the present study,we have described the general configuration of the RMS in adult monkey,fetal human and adult human brains.We provide evidence that neuroblasts exist continuously in the anterior ventral SVZ and RMS of the adult human brain.The neuroblasts appear singly or in pairs without forming chains; they exhibit migratory morphologies and co-express the immature neuronal markers doublecortin,polysialylated neural cell adhesion molecule and βI-tubulin.Few of these neuroblasts appear to be actively proliferating in the anterior ventral SVZ but none in the RMS,indicating that neuroblasts distributed along the RMS are most likely derived from the ventral SVZ.Interestingly,no neuroblasts are found in the adult human olfactory bulb.Taken together,our data suggest that the SVZ maintains the ability to produce neuroblasts in the adult human brain.

  12. Characterization of neural stem/progenitor cells expressing VEGF and its receptors in the subventricular zone of newborn piglet brain.

    Science.gov (United States)

    Ara, Jahan; Fekete, Saskia; Zhu, Anli; Frank, Melissa

    2010-09-01

    Neural stem/progenitor cell (NSP) biology and neurogenesis in adult central nervous system (CNS) are important both towards potential future therapeutic applications for CNS repair, and for the fundamental function of the CNS. In the present study, we report the characterization of NSP population from subventricular zone (SVZ) of neonatal piglet brain using in vivo and in vitro systems. We show that the nestin and vimentin-positive neural progenitor cells are present in the SVZ of the lateral ventricles of neonatal piglet brain. In vitro, piglet NSPs proliferated as neurospheres, expressed the typical protein of neural progenitors, nestin and a range of well-established neurodevelopmental markers. Upon dissociation and subculture, piglet NSPs differentiated into neurons and glial cells. Clonal analysis demonstrates that piglet NSPs are multipotent and retain the capacity to generate both glia and neurons. These cells expressed VEGF, VEGFR1, VEGFR2 and Neuropilin-1 and -2 mRNAs. Real time PCR revealed that SVZ NSPs from newborn piglet expressed total VEGF and all VEGF splice variants. These findings show that piglet NSPs may be helpful to more effectively design growth factor based strategies to enhance endogenous precursor cells for cell transplantation studies potentially leading to the application of this strategy in the nervous system disease and injury.

  13. Gypenosides Protected the Neural Stem Cells in the Subventricular Zone of Neonatal Rats that Were Prenatally Exposed to Ethanol

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    Lun Dong

    2014-11-01

    Full Text Available Fetal alcohol spectrum disorder (FASD can cause severe mental retardation in children who are prenatally exposed to ethanol. The effects of prenatal and early postnatal ethanol exposure on adult hippocampal neurogenesis have been investigated; however, the effects of prenatal ethanol exposure on the subventricular zone (SVZ have not. Gypenosides (GPs have been reported to have neuroprotective effects in addition to other bioactivities. The effects of GPs on neural stem cells (NSCs in the FASD model are unknown. Here, we test the effect of prenatal ethanol exposure on the neonatal SVZ, and the protection potential of GPs on NSCs in FASD rats. Our results show that prenatal ethanol exposure can suppress the cell proliferation and differentiation of neural stem cells in the neonatal SVZ and that GPs (400 mg/kg/day can significantly increase the cell proliferation and differentiation of neural stem cells inhibited by ethanol. Our data indicate that GPs have neuroprotective effects on the NSCs and can enhance the neurogenesis inhibited by ethanol within the SVZ of neonatal rats. These findings provide new evidence for a potential therapy involving GPs for the treatment of FASD.

  14. Anosmin-1 over-expression increases adult neurogenesis in the subventricular zone and neuroblast migration to the olfactory bulb.

    Science.gov (United States)

    García-González, Diego; Murcia-Belmonte, Verónica; Esteban, Pedro F; Ortega, Felipe; Díaz, David; Sánchez-Vera, Irene; Lebrón-Galán, Rafael; Escobar-Castañondo, Laura; Martínez-Millán, Luis; Weruaga, Eduardo; García-Verdugo, José Manuel; Berninger, Benedikt; de Castro, Fernando

    2016-01-01

    New subventricular zone (SVZ)-derived neuroblasts that migrate via the rostral migratory stream are continuously added to the olfactory bulb (OB) of the adult rodent brain. Anosmin-1 (A1) is an extracellular matrix protein that binds to FGF receptor 1 (FGFR1) to exert its biological effects. When mutated as in Kallmann syndrome patients, A1 is associated with severe OB morphogenesis defects leading to anosmia and hypogonadotropic hypogonadism. Here, we show that A1 over-expression in adult mice strongly increases proliferation in the SVZ, mainly with symmetrical divisions, and produces substantial morphological changes in the normal SVZ architecture, where we also report the presence of FGFR1 in almost all SVZ cells. Interestingly, for the first time we show FGFR1 expression in the basal body of primary cilia in neural progenitor cells. Additionally, we have found that A1 over-expression also enhances neuroblast motility, mainly through FGFR1 activity. Together, these changes lead to a selective increase in several GABAergic interneuron populations in different OB layers. These specific alterations in the OB would be sufficient to disrupt the normal processing of sensory information and consequently alter olfactory memory. In summary, this work shows that FGFR1-mediated A1 activity plays a crucial role in the continuous remodelling of the adult OB. PMID:25300351

  15. Severe instead of mild hyperglycemia inhibits neurogenesis in the subventricular zone of adult rats after transient focal cerebral ischemia.

    Science.gov (United States)

    Tan, S; Zhi, P K; Luo, Z K; Shi, J

    2015-09-10

    Accumulated evidence suggests that enhanced neurogenesis stimulated by ischemic injury contributes to stroke outcome. However, it is unclear whether hyperglycemia, which is frequently tested positive in patients with acute ischemic stroke, influences stroke-induced neurogenesis. The aim of the present study is to examine the effect of hyperglycemia on stroke-induced neurogenesis in a rat model of transient focal cerebral ischemia. For this purpose, adult male Sprague-Dawley rats (220-250 g) were subjected to 90 min of middle cerebral artery occlusion (MCAO). Glucose was administered during ischemia to produce target blood levels ranging from 4.83 ± 0.94 mM (normoglycemia) to 20.76 ± 1.56 mM. To label proliferating cells in ischemic ipsilateral subventricular zone (SVZ) of lateral ventricles, 5'-bromo-2'-deoxyuridine (BrdU) was injected 24h after MCAO. Brains were harvested 2h post-BrdU to evaluate the effects of hyperglycemia on infarct volume and SVZ cell proliferation. Rats that were severely hyperglycemic (19.26 ± 1.48 mM to 20.76 ± 1.56 mM) during ischemia had 24.26% increase in infarct volume (Pneurogenesis by a mechanism involving suppression of CREB and BDNF signaling. PMID:26126927

  16. A comparative study of the structural organization of spheres derived from the adult human subventricular zone and glioblastoma biopsies

    Energy Technology Data Exchange (ETDEWEB)

    Vik-Mo, Einar Osland, E-mail: e.o.vik-mo@medisin.uio.no [Vilhelm Magnus Laboratory for Neurosurgical Research, Institute for Surgical Research, Oslo University Hospital, Oslo (Norway); Department of Neurosurgery, Oslo University Hospital, Oslo (Norway); Sandberg, Cecilie [Vilhelm Magnus Laboratory for Neurosurgical Research, Institute for Surgical Research, Oslo University Hospital, Oslo (Norway); Joel, Mrinal [Vilhelm Magnus Laboratory for Neurosurgical Research, Institute for Surgical Research, Oslo University Hospital, Oslo (Norway); Department of Physiology, Institute of Basic Medical Sciences, University of Oslo (Norway); Stangeland, Biljana [Vilhelm Magnus Laboratory for Neurosurgical Research, Institute for Surgical Research, Oslo University Hospital, Oslo (Norway); Watanabe, Yasuhiro [Division of Neurology, Department of Brain and Neurosciences, Faculty of Medicine, Tottori University, 36-1 Nishi-cho, Yonago 683-8504 (Japan); Mackay-Sim, Alan [National Centre for Adult Stem Cell Research, Eskitis Institute for Cell and Molecular Therapies, Griffith University, Brisbane, QLD 4111 (Australia); Moe, Morten Carstens [Center for Eye Research, Department of Ophthalmology, Oslo University Hospital, Oslo (Norway); Murrell, Wayne [Vilhelm Magnus Laboratory for Neurosurgical Research, Institute for Surgical Research, Oslo University Hospital, Oslo (Norway); Langmoen, Iver Arne [Vilhelm Magnus Laboratory for Neurosurgical Research, Institute for Surgical Research, Oslo University Hospital, Oslo (Norway); Department of Neurosurgery, Oslo University Hospital, Oslo (Norway)

    2011-04-15

    Sphere forming assays have been useful to enrich for stem like cells in a range of tumors. The robustness of this system contrasts the difficulties in defining a stem cell population based on cell surface markers. We have undertaken a study to describe the cellular and organizational composition of tumorspheres, directly comparing these to neurospheres derived from the adult human subventricular zone (SVZ). Primary cell cultures from brain tumors were found to contain variable fractions of cells positive for tumor stem cell markers (CD133 (2-93%)/SSEA1 (3-15%)/CXCR4 (1-72%)). All cultures produced tumors upon xenografting. Tumorspheres contained a heterogeneous population of cells, but were structurally organized with stem cell markers present at the core of spheres, with markers of more mature glial progenitors and astrocytes at more peripheral location. Ultrastructural studies showed that tumorspheres contained a higher fraction of electron dense cells in the core than the periphery (36% and 19%, respectively). Neurospheres also contained a heterogeneous cell population, but did not have an organization similar to tumorspheres. Although tumorspheres clearly display irregular and neoplastic cells, they establish an organized structure with an outward gradient of differentiation. We suggest that this organization is central in maintaining the tumor stem cell pool.

  17. Indomethacin treatment reduces microglia activation and increases numbers of neuroblasts in the subventricular zone and ischaemic striatum after focal ischaemia

    Indian Academy of Sciences (India)

    ROSANA S LOPES; MARCELO M CARDOSO; ARTHUR O SAMPAIO; MARIO SANTOS BARBOSA Jr; CELICE C SOUZA; MICHELLE C DA SILVA; ELANE MAGNO N FERREIRA; MARCO AURELIOM FREIRE; RAFAEL RODRIGUES LIMA; WALACE GOMES-LEAL

    2016-09-01

    Neuroblasts from the subventricular zone (SVZ) migrate to striatum following stroke, but most of them die inthe ischaemic milieu and this can be related to exacerbated microglial activation. Here, we explored theeffects of the non-steroidal anti-inflammatory indomethacin on microglial activation, neuronal preservation andneuroblast migration following experimental striatal stroke in adult rats. Animals were submitted toendothelin-1 (ET-1)-induced focal striatal ischaemia and were treated with indomethacin or sterile saline(i.p.) for 7 days, being perfused after 8 or 14 days. Immunohistochemistry was performed to assess neuronalloss (anti-NeuN), microglial activation (anti-Iba1, ED1) and migrating neuroblasts (anti-DCX) by countingNeuN, ED1 and DCX-positive cells in the ischaemic striatum or SVZ. Indomethacin treatment reducedmicroglia activation and the number of ED1^{+} cells in both 8 and 14 days post injury as compared withcontrols. There was an increase in the number of DCX^{+} cells in both SVZ and striatum at the same survivaltimes. Moreover, there was a decrease in the number of NeuN^{+} cells in indomethacin-treated animals ascompared with the control group at 8 days but not after 14 days post injury. Our results suggest thatindomethacin treatment modulates microglia activation, contributing to increased neuroblast proliferation inthe SVZ and migration to the ischaemic striatum following stroke.

  18. Congenitally acquired persistent lymphocytic choriomeningitis viral infection reduces neuronal progenitor pools in the adult hippocampus and subventricular zone.

    Directory of Open Access Journals (Sweden)

    Tony Sun

    Full Text Available Lymphocytic choriomeningitis virus (LCMV can be transmitted through congenital infection, leading to persistent infection of numerous organ systems including the central nervous system (CNS. Adult mice persistently infected with LCMV (LCMV-cgPi mice exhibit learning deficits, such as poor performance in spatial discrimination tests. Given that deficits in spatial learning have been linked to defects in adult neurogenesis, we investigated the impact of congenital LCMV infection on generation of neuroblasts from neural progenitor cells within neurogenic zones of adult mice. In LCMV-cgPi mice, QPCR and immunohistochemistry detected presence of LCMV glycoprotein-coding RNA and nucleoprotein in the hippocampal dentate gyrus and subventricular zone (SVZ, sites of neurogenesis that harbor populations of neuroblasts. Numbers of neuroblasts were reduced in LCMV-cgPi mice, as determined by IHC quantification, and analysis of BrdU incorporation by flow cytometry revealed lower numbers of BrdU-labeled neuroblasts. Additionally, TUNEL assays performed in situ showed increased numbers of apoptotic cells in the two neurogenic regions. Next, neurosphere cultures were infected in vitro with LCMV and differentiated to create a population of cells that consisted of both transit amplifying cells and neuroblasts. Immunocytochemical and TUNEL assays revealed increased numbers of TUNEL-positive cells that express nestin, suggesting that the drop in numbers of neuroblasts was due to a combination of impaired proliferation and apoptosis of progenitor cells. LCMV-cgPi mice exhibited transcriptional up-regulation several cytokines and chemokines, including gamma-interferon inducible chemokines CXCL9 and CXCL10. Chronic up-regulation of these chemokines can facilitate a pro-inflammatory niche that may contribute to defects in neurogenesis.

  19. SSEA-4 and YKL-40 positive progenitor subtypes in the subventricular zone of developing human neocortex

    DEFF Research Database (Denmark)

    Brøchner, Christian B; Møllgård, Kjeld

    2016-01-01

    The glycosphingolipid SSEA-4 and the glycoprotein YKL-40 have both been associated with human embryonic and neural stem cell differentiation. We investigated the distribution of SSEA-4 and YKL-40 positive cells in proliferative zones of human fetal forebrain using immunohistochemistry and double...... characterized by immunohistochemical combination of antibodies against SSEA-4 and YKL-40 and devoid of neuronal and microglial markers represent a yet unexplored astrogenic lineage illustrating the complexity of astroglial development. GLIA 2015....

  20. Selective depletion of Mac-1-expressing microglia in rat subventricular zone does not alter neurogenic response early after stroke.

    Science.gov (United States)

    Heldmann, Ursula; Mine, Yutaka; Kokaia, Zaal; Ekdahl, Christine T; Lindvall, Olle

    2011-06-01

    Ischemic stroke induces migration of newly formed neuroblasts, generated by neural stem cells in the adult rat subventricular zone (SVZ), towards the injured striatum where they differentiate into mature neurons. Stroke also leads to accumulation of microglia in the SVZ but their role for neurogenesis is unclear. Here we developed a method for selective depletion of the macrophage antigen complex-1 (Mac-1)-expressing microglia population in the SVZ by intraventricular injection of the immunotoxin Mac-1-saporin in rats. We found that the vast majority of Mac-1+ cells were Iba-1+ microglia. The Mac-1+ population was heterogeneous and included both a small proliferative pool of cells, which was not affected by middle cerebral artery occlusion (MCAO), and a larger subpopulation that changed morphologically into a semi-activated state in response to the insult. This subpopulation did not increase its expression of the phagocytic marker ED1 but exhibited high levels of triggering receptor expressed on myeloid cells-2 (TREM-2), associated with alternative microglia activation. A minor portion of the SVZ Mac-1+ cells originated from the blood early after stroke, but this macrophage population became much more substantial at later stages. Almost 80% reduction of Mac-1-expressing microglia, caused by Mac-1 saporin delivered just before and at 1 week after MCAO, did not alter the numbers of newly formed neuroblasts in the striatum or their migratory distance. These findings indicate that the Mac-1-expressing microglia in the SVZ do not play a major role either for the number of neuroblasts which exit the SVZ or their migration in the striatum early following stroke.

  1. Neural progenitor cells isolated from the subventricular zone present hemichannel activity and form functional gap junctions with glial cells.

    Science.gov (United States)

    Talaverón, Rocío; Fernández, Paola; Escamilla, Rosalba; Pastor, Angel M; Matarredona, Esperanza R; Sáez, Juan C

    2015-01-01

    The postnatal subventricular zone (SVZ) lining the walls of the lateral ventricles contains neural progenitor cells (NPCs) that generate new olfactory bulb interneurons. Communication via gap junctions between cells in the SVZ is involved in NPC proliferation and in neuroblast migration towards the olfactory bulb. SVZ NPCs can be expanded in vitro in the form of neurospheres that can be used for transplantation purposes after brain injury. We have previously reported that neurosphere-derived NPCs form heterocellular gap junctions with host glial cells when they are implanted after mechanical injury. To analyze functionality of NPC-glial cell gap junctions we performed dye coupling experiments in co-cultures of SVZ NPCs with astrocytes or microglia. Neurosphere-derived cells expressed mRNA for at least the hemichannel/gap junction channel proteins connexin 26 (Cx26), Cx43, Cx45 and pannexin 1 (Panx1). Dye coupling experiments revealed that gap junctional communication occurred among neurosphere cells (incidence of coupling: 100%). Moreover, hemichannel activity was also detected in neurosphere cells as evaluated in time-lapse measurements of ethidium bromide uptake. Heterocellular coupling between NPCs and glial cells was evidenced in co-cultures of neurospheres with astrocytes (incidence of coupling: 91.0 ± 4.7%) or with microglia (incidence of coupling: 71.9 ± 6.7%). Dye coupling in neurospheres and in co-cultures was inhibited by octanol, a gap junction blocker. Altogether, these results suggest the existence of functional hemichannels and gap junction channels in postnatal SVZ neurospheres. In addition, they demonstrate that SVZ-derived NPCs can establish functional gap junctions with astrocytes or microglia. Therefore, cell-cell communication via gap junctions and hemichannels with host glial cells might subserve a role in the functional integration of NPCs after implantation in the damaged brain.

  2. PPARβ/δ and PPARγ maintain undifferentiated phenotypes of mouse adult neural precursor cells from the subventricular zone.

    Science.gov (United States)

    Bernal, Carolina; Araya, Claudia; Palma, Verónica; Bronfman, Miguel

    2015-01-01

    The subventricular zone (SVZ) is one of the main niches of neural stem cells in the adult mammalian brain. Stem and precursor cells in this region are the source for neurogenesis and oligodendrogesis, mainly in the olfactory bulb and corpus callosum, respectively. The identification of the molecular components regulating the decision of these cells to differentiate or maintain an undifferentiated state is important in order to understand the modulation of neurogenic processes in physiological and pathological conditions. PPARs are a group of transcription factors, activated by lipid ligands, with important functions in cellular differentiation and proliferation in several tissues. In this work, we demonstrate that mouse adult neural precursor cells (NPCs), in situ and in vitro, express PPARβ/δ and PPARγ. Pharmacological activation of both PPARs isoforms induces proliferation and maintenance of the undifferentiated phenotype. Congruently, inhibition of PPARβ/δ and PPARγ results in a decrease of proliferation and loss of the undifferentiated phenotype. Interestingly, PPARγ regulates the level of EGFR in adult NPCs, concurrent with it is function described in embryonic NPCs. Furthermore, we describe for the first time that PPARβ/δ regulates SOX2 level in adult NPCs, probably through a direct transcriptional regulation, as we identified two putative PPAR response elements in the promoter region of Sox2. EGFR and SOX2 are key players in neural stem/precursor cells self-renewal. Finally, rosiglitazone, a PPARγ ligand, increases PPARβ/δ level, suggesting a possible cooperation between these two PPARs in the control of cell fate behavior. Our work contributes to the understanding of the molecular mechanisms associated to neural cell fate decision and places PPARβ/δ and PPARγ as interesting new targets of modulation of mammalian brain homeostasis. PMID:25852474

  3. Elevated adult neurogenesis in brain subventricular zone following in vivo manganese exposure: roles of copper and DMT1.

    Science.gov (United States)

    Fu, Sherleen; O'Neal, Stefanie; Hong, Lan; Jiang, Wendy; Zheng, Wei

    2015-02-01

    The brain subventricular zone (SVZ) is a source of neural precursor cells; these cells travel along the rostral migratory stream (RMS) to destination areas in the process of adult neurogenesis. Recent x-ray fluorescence (XRF) studies reveal an extensive accumulation of copper (Cu) in the SVZ. Earlier human and animal studies also suggest an altered Cu homeostasis after manganese (Mn) exposure. This study was designed to test the hypothesis that Mn exposure by acting on the divalent metal transporter-1 (DMT1) altered Cu levels in SVZ and RMS, thereby affecting adult neurogenesis. Adult rats received intraperitoneal (i.p.) injections of 6 mg Mn/kg as MnCl2 once daily for 4 weeks with concomitant injections of bromodeoxyuridine (BrdU) for 5 days in the last week. In control rats, Cu levels were significantly higher in the SVZ than other brain regions examined. Mn exposure significantly reduced Cu concentrations in the SVZ (P exposure significantly increased numbers of BrdU(+) cells, which were accompanied with increased GFAP(+) astrocytic stem cells and DCX(+) neuroblasts in SVZ and RMS. Quantitative RT-PCR and Western blot confirmed the increased expression of DMT1 in SVZ following in vivo Mn exposure, which contributed to Mn accumulation in the neurogenesis pathway. Taken together, these results indicate a clear disruptive effect of Mn on adult neurogenesis; the effect appears due partly to Mn induction of DMT1 and its interference with cellular Cu regulation in SVZ and RMS. The future research directions based on these observations are also discussed. PMID:25575534

  4. S phase entry of neural progenitor cells correlates with increased blood flow in the young subventricular zone.

    Directory of Open Access Journals (Sweden)

    Benjamin Lacar

    Full Text Available The postnatal subventricular zone (SVZ contains proliferating neural progenitor cells in close proximity to blood vessels. Insults and drug treatments acutely stimulate cell proliferation in the SVZ, which was assessed by labeling cells entering S phase. Although G1-to-S progression is metabolically demanding on a minute-to-hour time scale, it remains unknown whether increased SVZ cell proliferation is accompanied by a local hemodynamic response. This neurovascular coupling provides energy substrates to active neuronal assemblies. Transcardial dye perfusion revealed the presence of capillaries throughout the SVZ that constrict upon applications of the thromboxane A(2 receptor agonist U-46119 in acute brain slice preparations. We then monitored in vivo blood flow using laser Doppler flowmetry via a microprobe located either in the SVZ or a mature network. U-46119 injections into the lateral ventricle decreased blood flow in the SVZ and the striatum, which are near the ventricle. A 1-hour ventricular injection of epidermal and basic fibroblast growth factor (EGF and bFGF significantly increased the percentage of Sox2 transcription factor-positive cells in S phase 1.5 hours post-injection. This increase was accompanied by a sustained rise in blood flow in the SVZ but not in the striatum. Direct growth factor injections into the cortex did not alter local blood flow, ruling out direct effects on capillaries. These findings suggest that an acute increase in the number of G1-to-S cycling SVZ cells is accompanied by neurometabolic-vascular coupling, which may provide energy and nutrient for cell cycle progression.

  5. Neural progenitor cells isolated from the subventricular zone present hemichannel activity and form functional gap junctions with glial cells

    Science.gov (United States)

    Talaverón, Rocío; Fernández, Paola; Escamilla, Rosalba; Pastor, Angel M.; Matarredona, Esperanza R.; Sáez, Juan C.

    2015-01-01

    The postnatal subventricular zone (SVZ) lining the walls of the lateral ventricles contains neural progenitor cells (NPCs) that generate new olfactory bulb interneurons. Communication via gap junctions between cells in the SVZ is involved in NPC proliferation and in neuroblast migration towards the olfactory bulb. SVZ NPCs can be expanded in vitro in the form of neurospheres that can be used for transplantation purposes after brain injury. We have previously reported that neurosphere-derived NPCs form heterocellular gap junctions with host glial cells when they are implanted after mechanical injury. To analyze functionality of NPC-glial cell gap junctions we performed dye coupling experiments in co-cultures of SVZ NPCs with astrocytes or microglia. Neurosphere-derived cells expressed mRNA for at least the hemichannel/gap junction channel proteins connexin 26 (Cx26), Cx43, Cx45 and pannexin 1 (Panx1). Dye coupling experiments revealed that gap junctional communication occurred among neurosphere cells (incidence of coupling: 100%). Moreover, hemichannel activity was also detected in neurosphere cells as evaluated in time-lapse measurements of ethidium bromide uptake. Heterocellular coupling between NPCs and glial cells was evidenced in co-cultures of neurospheres with astrocytes (incidence of coupling: 91.0 ± 4.7%) or with microglia (incidence of coupling: 71.9 ± 6.7%). Dye coupling in neurospheres and in co-cultures was inhibited by octanol, a gap junction blocker. Altogether, these results suggest the existence of functional hemichannels and gap junction channels in postnatal SVZ neurospheres. In addition, they demonstrate that SVZ-derived NPCs can establish functional gap junctions with astrocytes or microglia. Therefore, cell-cell communication via gap junctions and hemichannels with host glial cells might subserve a role in the functional integration of NPCs after implantation in the damaged brain. PMID:26528139

  6. Activation of type 1 cannabinoid receptor (CB1R promotes neurogenesis in murine subventricular zone cell cultures.

    Directory of Open Access Journals (Sweden)

    Sara Xapelli

    Full Text Available The endocannabinoid system has been implicated in the modulation of adult neurogenesis. Here, we describe the effect of type 1 cannabinoid receptor (CB1R activation on self-renewal, proliferation and neuronal differentiation in mouse neonatal subventricular zone (SVZ stem/progenitor cell cultures. Expression of CB1R was detected in SVZ-derived immature cells (Nestin-positive, neurons and astrocytes. Stimulation of the CB1R by (R-(+-Methanandamide (R-m-AEA increased self-renewal of SVZ cells, as assessed by counting the number of secondary neurospheres and the number of Sox2+/+ cell pairs, an effect blocked by Notch pathway inhibition. Moreover, R-m-AEA treatment for 48 h, increased proliferation as assessed by BrdU incorporation assay, an effect mediated by activation of MAPK-ERK and AKT pathways. Surprisingly, stimulation of CB1R by R-m-AEA also promoted neuronal differentiation (without affecting glial differentiation, at 7 days, as shown by counting the number of NeuN-positive neurons in the cultures. Moreover, by monitoring intracellular calcium concentrations ([Ca(2+]i in single cells following KCl and histamine stimuli, a method that allows the functional evaluation of neuronal differentiation, we observed an increase in neuronal-like cells. This proneurogenic effect was blocked when SVZ cells were co-incubated with R-m-AEA and the CB1R antagonist AM 251, for 7 days, thus indicating that this effect involves CB1R activation. In accordance with an effect on neuronal differentiation and maturation, R-m-AEA also increased neurite growth, as evaluated by quantifying and measuring the number of MAP2-positive processes. Taken together, these results demonstrate that CB1R activation induces proliferation, self-renewal and neuronal differentiation from mouse neonatal SVZ cell cultures.

  7. Adult mouse subventricular zone stem and progenitor cells are sessile and epidermal growth factor receptor negatively regulates neuroblast migration.

    Directory of Open Access Journals (Sweden)

    Yongsoo Kim

    Full Text Available BACKGROUND: The adult subventricular zone (SVZ contains stem and progenitor cells that generate neuroblasts throughout life. Although it is well accepted that SVZ neuroblasts are migratory, recent evidence suggests their progenitor cells may also exhibit motility. Since stem and progenitor cells are proliferative and multipotential, if they were also able to move would have important implications for SVZ neurogenesis and its potential for repair. METHODOLOGY/PRINCIPAL FINDINGS: We studied whether SVZ stem and/or progenitor cells are motile in transgenic GFP+ slices with two photon time lapse microscopy and post hoc immunohistochemistry. We found that stem and progenitor cells; mGFAP-GFP+ cells, bright nestin-GFP+ cells and Mash1+ cells were stationary in the SVZ and rostral migratory stream (RMS. In our search for motile progenitor cells, we uncovered a population of motile betaIII-tubulin+ neuroblasts that expressed low levels of epidermal growth factor receptor (EGFr. This was intriguing since EGFr drives proliferation in the SVZ and affects migration in other systems. Thus we examined the potential role of EGFr in modulating SVZ migration. Interestingly, EGFr(low neuroblasts moved slower and in more tortuous patterns than EGFr-negative neuroblasts. We next questioned whether EGFr stimulation affects SVZ cell migration by imaging Gad65-GFP+ neuroblasts in the presence of transforming growth factor alpha (TGF-alpha, an EGFr-selective agonist. Indeed, acute exposure to TGF-alpha decreased the percentage of motile cells by approximately 40%. CONCLUSIONS/SIGNIFICANCE: In summary, the present study directly shows that SVZ stem and progenitor cells are static, that EGFr is retained on some neuroblasts, and that EGFr stimulation negatively regulates migration. This result suggests an additional role for EGFr signaling in the SVZ.

  8. BTG1 is required to maintain the pool of stem and progenitor cells of dentate gyrus and subventricular zone

    Directory of Open Access Journals (Sweden)

    Stefano eFarioli-Vecchioli

    2012-08-01

    Full Text Available Btg1 belongs to a family of cell cycle inhibitory genes. We observed that Btg1 is highly expressed in adult neurogenic niches, i.e., the dentate gyrus and subventricular zone (SVZ. Thus, we generated Btg1 knockout mice to analyze the role of Btg1 in the process of generation of adult new neurons.Ablation of Btg1 causes a transient increase of the proliferating dentate gyrus stem and progenitor cells at post-natal day 7; however, at two months of age the number of these proliferating cells, as well as of mature neurons, greatly decreases compared to wild-type controls. Remarkably, adult dentate gyrus stem and progenitor cells of Btg1-null mice exit cell cycle after completing the S phase, highly express p53 and p21, and within 5 days undergo apoptosis. In SVZ we observed an equivalent decrease, associated to apoptosis, of Btg1-null stem cells, neuroblasts and neurons; furthermore, neurospheres derived from SVZ stem cells showed an age-dependent decrease of the self-renewal and expansion capacity.We conclude that the ablation of Btg1 reduces the pool of dividing adult stem and progenitor cells in dentate gyrus and SVZ by decreasing their proliferative capacity and inducing apoptosis, likely reflecting the impairment of the control of the cell cycle transition from G1 to S phase. As a result, the ability of Btg1-null mice to discriminate among overlapping contextual memories was affected. Thus, Btg1 appears to be required for maintaining adult stem and progenitor cells quiescence and self-renewal.

  9. SSEA-4 and YKL-40 positive progenitor subtypes in the subventricular zone of developing human neocortex

    DEFF Research Database (Denmark)

    Brøchner, Christian B; Møllgård, Kjeld

    2016-01-01

    . Adjacent to the ventricular zone, a minor fraction showed overlap with GFAP but not with nestin, Olig2, NG2, or S100. No co-localization was found with neuronal markers NeuN, calbindin, DCX or with markers for microglial cells (Iba-1, CD68). Moreover, the SSEA-4 and YKL-40 positive cell population...... characterized by immunohistochemical combination of antibodies against SSEA-4 and YKL-40 and devoid of neuronal and microglial markers represent a yet unexplored astrogenic lineage illustrating the complexity of astroglial development. GLIA 2015....

  10. Metallic gold treatment reduces proliferation of inflammatory cells, increases expression of VEGF and FGF, and stimulates cell proliferation in the subventricular zone following experimental traumatic brain injury

    DEFF Research Database (Denmark)

    Pedersen, Mie Østergaard; Larsen, Agnete; Pedersen, Dan Sonne;

    2009-01-01

    Traumatic brain injury represents a leading cause of morbidity in young individuals and there is an imperative need for neuroprotective treatments limiting the neurologic impairment following such injury. It has recently been demonstrated that bio-liberated gold ions liberated from small metallic...... increase in cell proliferation in both the ipsilateral and the contralateral subventricular zone was found in response to gold-treatment. In conclusion: we confirmed the previously demonstrated anti-inflammatory effect of bio-liberated gold ions, and further show that metallic gold increases growth factor...

  11. Chronic treatment with fluoxetine for more than 6 weeks decreases neurogenesis in the subventricular zone of adult mice

    Directory of Open Access Journals (Sweden)

    Ohira Koji

    2011-03-01

    Full Text Available Abstract Background Recent studies indicate that chronic treatment with serotonergic antidepressants upregulates adult neurogenesis of the dentate gyrus (DG. In contrast, some studies claimed that there was very little alteration of neurogenesis in the subventricular zone (SVZ by the antidepressants. Since almost all of those studies treated animals with drugs for 2 to 4 weeks as chronic treatment models of antidepressants, it is possible that antidepressant treatments for longer periods would affect adult neurogenesis in the SVZ. Results In the present study, we examined the effects of long-term (up to 9 weeks administration of fluoxetine (FLX, a selective serotonin reuptake inhibitor, on cell proliferation and survival in the DG and the SVZ of adult mice. As reported previously, in the DG of mice treated with FLX for 3, 6, or 9 weeks that were also injected with 5-bromodeoxyuridine (BrdU in the last 3 days before perfusion, the numbers of Ki67- and BrdU-positive cells, which are cell proliferation markers, were significantly upregulated even at 3 weeks after the onset of the FLX treatments, and these increases were sustained in mice treated with FLX for 9 weeks. On the other hand, in the SVZ, we found a small, insignificant decrease in the numbers of Ki67- and BrdU-positive cells at 3 weeks, followed by highly significant decreases in the numbers of Ki67- and BrdU-positive cells at both 6 and 9 weeks. Furthermore, among olfactory newly generated cells that survived for 3 weeks after BrdU injection, the number of new cells was decreased at 9 weeks of FLX treatment. Conclusions These results demonstrate that long-term (more than 6 weeks treatment with FLX has the opposite effect on neurogenesis in the SVZ than it does in the DG. The results also suggest that the decrease in neurogenesis in the SVZ might be involved in some aspects of the drugs' therapeutic effects on depression. In addition, our findings raise the possibility that some of the

  12. Functional electrical stimulation increases neural stem/progenitor cell proliferation and neurogenesis in the subventricular zone of rats with stroke

    Institute of Scientific and Technical Information of China (English)

    LIU Hui-hua; XIANG Yun; YAN Tie-bin; TAN Zhi-mei; LI Sheng-huo; HE Xiao-kuo

    2013-01-01

    Background Functional electrical stimulation (FES) is known to promote the recovery of motor function in rats with ischemia and to upregulate the expression of growth factors which support brain neurogenesis.In this study,we investigated whether postischemic FES could improve functional outcomes and modulate neurogenesis in the subventricular zone (SVZ) after focal cerebral ischemia.Methods Adult male Sprague-Dawley rats with permanent middle cerebral artery occlusion (MCAO) were randomly assigned to the control group,the placebo stimulation group,and the FES group.The rats in each group were further assigned to one of four therapeutic periods (1,3,7,or 14 days).FES was delivered 48 hours after the MCAO procedure and divided into two 10-minute sessions on each day of treatment with a 10-minute rest between them.Two intraperitoneal injections of bromodeoxyuridine (BrdU) were given 4 hours apart every day beginning 48 hours after the MCAO.Neurogenesis was evaluated by immunofluorescence staining.Wnt-3 which is strongly implicated in the proliferation and differentiation of neural stem cells (NSCs) was investigated by Western blotting analysis.The data wera subjected to oneway analysis of variance (ANOVA),followed by a Tukey/Kramer or Dunnett post hoc test.Results FES significantly increased the number of BrdU-positive cells and BrdU/glial flbrillary acidic protein doublepositive neural progenitor cells in the SVZ on days 7 and 14 of the treatment (P <0.05).The number of BrdU/doublecortin (DCX) double-positive migrating neuroblast cells in the ipsilateral SVZ on day 14 of the FES treatment group ((522.77±33.32) cells/mm2) was significantly increased compared with the control group ((262.58±35.11) cells/mm2,P <0.05) and the placebo group ((266.17±47.98) cells/mm2,P <0.05).However,only a few BrdU/neuron-specific nuclear protein-positive cells were observed by day 14 of the treatment.At day 7,Wnt-3 was upregulated in the ipsilateral SVZs of the rats receiving

  13. Age-related neurogenesis decline in the subventricular zone is associated with specific cell cycle regulation changes in activated neural stem cells.

    Science.gov (United States)

    Daynac, Mathieu; Morizur, Lise; Chicheportiche, Alexandra; Mouthon, Marc-André; Boussin, François D

    2016-01-01

    Although neural stem cells (NSCs) sustain continuous neurogenesis throughout the adult lifespan of mammals, they progressively exhibit proliferation defects that contribute to a sharp reduction in subventricular neurogenesis during aging. However, little is known regarding the early age-related events in neurogenic niches. Using a fluorescence-activated cell sorting technique that allows for the prospective purification of the main neurogenic populations from the subventricular zone (SVZ), we demonstrated an early decline in adult neurogenesis with a dramatic loss of progenitor cells in 4 month-old young adult mice. Whereas the activated and quiescent NSC pools remained stable up to 12 months, the proliferative status of activated NSCs was already altered by 6 months, with an overall extension of the cell cycle resulting from a specific lengthening of G1. Whole genome analysis of activated NSCs from 2- and 6-month-old mice further revealed distinct transcriptomic and molecular signatures, as well as a modulation of the TGFβ signalling pathway. Our microarray study constitutes a cogent identification of new molecular players and signalling pathways regulating adult neurogenesis and its early modifications. PMID:26893147

  14. Early Inflammatory Responses Following Cell Grafting in the CNS Trigger Activation of the Subventricular Zone: A Proposed Model of Sequential Cellular Events.

    Science.gov (United States)

    Praet, Jelle; Santermans, Eva; Daans, Jasmijn; Le Blon, Debbie; Hoornaert, Chloé; Goossens, Herman; Hens, Niel; Van der Linden, Annemie; Berneman, Zwi; Ponsaerts, Peter

    2015-01-01

    While multiple rodent preclinical studies, and to a lesser extent human clinical trials, claim the feasibility, safety, and potential clinical benefit of cell grafting in the central nervous system (CNS), currently only little convincing knowledge exists regarding the actual fate of the grafted cells and their effect on the surrounding environment (or vice versa). Our preceding studies already indicated that only a minor fraction of the initially grafted cell population survives the grafting process, while the surviving cell population becomes invaded by highly activated microglia/macrophages and surrounded by reactive astrogliosis. In the current study, we further elaborate on early cellular and inflammatory events following syngeneic grafting of eGFP(+) mouse embryonic fibroblasts (mEFs) in the CNS of immunocompetent mice. Based on obtained quantitative histological data, we here propose a detailed mathematically derived working model that sequentially comprises hypoxia-induced apoptosis of grafted mEFs, neutrophil invasion, neoangiogenesis, microglia/macrophage recruitment, astrogliosis, and eventually survival of a limited number of grafted mEFs. Simultaneously, we observed that the cellular events following mEF grafting activates the subventricular zone neural stem and progenitor cell compartment. This proposed model therefore further contributes to our understanding of cell graft-induced cellular responses and will eventually allow for successful manipulation of this intervention.

  15. Neuroprotection by Exendin-4 Is GLP-1 Receptor Specific but DA D3 Receptor Dependent, Causing Altered BrdU Incorporation in Subventricular Zone and Substantia Nigra

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    A. Harkavyi

    2013-01-01

    Full Text Available Glucagon-like peptide-1 receptor (GLP-1R activation by exendin-4 (EX-4 is effective in preclinical models of Parkinson’s disease (PD and appears to promote neurogenesis even in severely lesioned rats. In the present study, we determined the effects of EX-4 on cellular BrdU incorporation in the rat subventricular zone (SVZ and substantia nigra (SN. We also determined the specificity of this effect with the GLP-1R antagonist EX-(9-39 as well as the potential role of dopamine (DA D3 receptors. Rats were administered 6-OHDA and 1 week later given EX-4 alone, with EX-(9-39 or nafadotride (D3 antagonist and BrdU. Seven days later, rats were challenged with apomorphine to evaluate circling. Extracellular DA was measured using striatal microdialysis and subsequently tissue DA measured. Tyrosine hydroxylase and BrdU were verified using immunohistochemistry. Apomorphine circling was reversed by EX-4 in lesioned rats, an effect reduced by EX-4, while both EX-(9-39 and NAF attenuated this. 6-OHDA decreased extracellular and tissue DA, both reversed by EX-4 but again attenuated by EX-(9-39 or NAF. Analysis of BrdU+ cells in the SVZ revealed increases in 6-OHDA-treated rats which were reversed by EX-4 and antagonised by either EX-(9-39 or NAF, while in the SN the opposite profile was seen.

  16. CD133 is not present on neurogenic astrocytes in the adult subventricular zone, but on embryonic neural stem cells, ependymal cells, and glioblastoma cells.

    Science.gov (United States)

    Pfenninger, Cosima V; Roschupkina, Teona; Hertwig, Falk; Kottwitz, Denise; Englund, Elisabet; Bengzon, Johan; Jacobsen, Sten Eirik; Nuber, Ulrike A

    2007-06-15

    Human brain tumor stem cells have been enriched using antibodies against the surface protein CD133. An antibody recognizing CD133 also served to isolate normal neural stem cells from fetal human brain, suggesting a possible lineage relationship between normal neural and brain tumor stem cells. Whether CD133-positive brain tumor stem cells can be derived from CD133-positive neural stem or progenitor cells still requires direct experimental evidence, and an important step toward such investigations is the identification and characterization of normal CD133-presenting cells in neurogenic regions of the embryonic and adult brain. Here, we present evidence that CD133 is a marker for embryonic neural stem cells, an intermediate radial glial/ependymal cell type in the early postnatal stage, and for ependymal cells in the adult brain, but not for neurogenic astrocytes in the adult subventricular zone. Our findings suggest two principal possibilities for the origin of brain tumor stem cells: a derivation from CD133-expressing cells, which are normally not present in the adult brain (embryonic neural stem cells and an early postnatal intermediate radial glial/ependymal cell type), or from CD133-positive ependymal cells in the adult brain, which are, however, generally regarded as postmitotic. Alternatively, brain tumor stem cells could be derived from proliferative but CD133-negative neurogenic astrocytes in the adult brain. In the latter case, brain tumor development would involve the production of CD133. PMID:17575139

  17. RE1 silencing transcription factor/neuron-restrictive silencing factor regulates expansion of adult mouse subventricular zone-derived neural stem/progenitor cells in vitro.

    Science.gov (United States)

    Soldati, Chiara; Caramanica, Pasquale; Burney, Matthew J; Toselli, Camilla; Bithell, Angela; Augusti-Tocco, Gabriella; Stanton, Lawrence W; Biagioni, Stefano; Buckley, Noel J; Cacci, Emanuele

    2015-08-01

    Adult neural stem cell (aNSC) activity is tuned by external stimuli through the recruitment of transcription factors. This study examines the RE1 silencing transcription factor (REST) in neural stem/progenitor cells isolated from the subventricular zone of adult mouse brain and provides the first extensive characterization of REST-mediated control of the cellular and molecular properties. This study shows that REST knockdown affects the capacity of progenitor cells to generate neurospheres, reduces cell proliferation, and triggers cell differentiation despite the presence of growth factors. Genome- and transcriptome-wide analyses show that REST binding sites are significantly enriched in genes associated with synaptic transmission and nervous system development and function. Seeking candidate regulators of aNSC function, this study identifies a member of the bone morphogenetic protein (BMP) family, BMP6, the mRNA and protein of which increased after REST knockdown. The results of this study extend previous findings, demonstrating a reciprocal control of REST expression by BMPs. Administration of exogenous BMP6 inhibits aNSC proliferation and induces the expression of the astrocytic marker glial fibrillary acidic protein, highlighting its antimitogenic and prodifferentiative effects. This study suggests that BMP6 produced in a REST-regulated manner together with other signals can contribute to regulation of NSC maintenance and fate. PMID:25691247

  18. The Effect of Pro-Neurogenic Gene Expression on Adult Subventricular Zone Precursor Cell Recruitment and Fate Determination After Excitotoxic Brain Injury

    Science.gov (United States)

    Jones, Kathryn S; Connor, Bronwen J

    2016-01-01

    Despite the presence of on-going neurogenesis in the adult mammalian brain, neurons are generally not replaced after injury. Using a rodent model of excitotoxic cell loss and retroviral (RV) lineage tracing, we previously demonstrated transient recruitment of precursor cells from the subventricular zone (SVZ) into the lesioned striatum. In the current study we determined that these cells included migratory neuroblasts and oligodendrocyte precursor cells (OPC), with the predominant response from glial cells. We attempted to override this glial response by ectopic expression of the pro-neurogenic genes Pax6 or Dlx2 in the adult rat SVZ following quinolinic acid lesioning. RV-Dlx2 over-expression stimulated repair at a previously non-neurogenic time point by enhancing neuroblast recruitment and the percentage of cells that retained a neuronal fate within the lesioned area, compared to RV-GFP controls. RV-Pax6 expression was unsuccessful at inhibiting glial fate and intriguingly, increased OPC cell numbers with no change in neuronal recruitment. These findings suggest that gene choice is important when attempting to augment endogenous repair as the lesioned environment can overcome pro-neurogenic gene expression. Dlx2 over-expression however was able to partially overcome an anti-neuronal environment and therefore is a promising candidate for further study of striatal regeneration.

  19. Cell Sorting of Neural Stem and Progenitor Cells from the Adult Mouse Subventricular Zone and Live-imaging of their Cell Cycle Dynamics.

    Science.gov (United States)

    Daynac, Mathieu; Morizur, Lise; Kortulewski, Thierry; Gauthier, Laurent R; Ruat, Martial; Mouthon, Marc-André; Boussin, François D

    2015-01-01

    Neural stem cells (NSCs) in the subventricular zone of the lateral ventricles (SVZ) sustain olfactory neurogenesis throughout life in the mammalian brain. They successively generate transit amplifying cells (TACs) and neuroblasts that differentiate into neurons once they integrate the olfactory bulbs. Emerging fluorescent activated cell sorting (FACS) techniques have allowed the isolation of NSCs as well as their progeny and have started to shed light on gene regulatory networks in adult neurogenic niches. We report here a cell sorting technique that allows to follow and distinguish the cell cycle dynamics of the above-mentioned cell populations from the adult SVZ with a LeX/EGFR/CD24 triple staining. Isolated cells are then plated as adherent cells to explore in details their cell cycle progression by time-lapse video microscopy. To this end, we use transgenic Fluorescence Ubiquitination Cell Cycle Indicator (FUCCI) mice in which cells are red-fluorescent during G1 phase due to a G1 specific red-Cdt1 reporter. This method has recently revealed that proliferating NSCs progressively lengthen their G1 phase during aging, leading to neurogenesis impairment. This method is easily transposable to other systems and could be of great interest for the study of the cell cycle dynamics of brain cells in the context of brain pathologies. PMID:26436641

  20. Inhibition of the histone demethylase Kdm5b promotes neurogenesis and derepresses Reln (reelin) in neural stem cells from the adult subventricular zone of mice.

    Science.gov (United States)

    Zhou, Qiong; Obana, Edwin A; Radomski, Kryslaine L; Sukumar, Gauthaman; Wynder, Christopher; Dalgard, Clifton L; Doughty, Martin L

    2016-02-15

    The role of epigenetic regulators in the control of adult neurogenesis is largely undefined. We show that the histone demethylase enzyme Kdm5b (Jarid1b) negatively regulates neurogenesis from adult subventricular zone (SVZ) neural stem cells (NSCs) in culture. shRNA-mediated depletion of Kdm5b in proliferating adult NSCs decreased proliferation rates and reduced neurosphere formation in culture. When transferred to differentiation culture conditions, Kdm5b-depleted adult NSCs migrated from neurospheres with increased velocity. Whole-genome expression screening revealed widespread transcriptional changes with Kdm5b depletion, notably the up-regulation of reelin (Reln), the inhibition of steroid biosynthetic pathway component genes and the activation of genes with intracellular transport functions in cultured adult NSCs. Kdm5b depletion increased extracellular reelin concentration in the culture medium and increased phosphorylation of the downstream reelin signaling target Disabled-1 (Dab1). Sequestration of extracellular reelin with CR-50 reelin-blocking antibodies suppressed the increase in migratory velocity of Kdm5b-depleted adult NSCs. Chromatin immunoprecipitation revealed that Kdm5b is present at the proximal promoter of Reln, and H3K4me3 methylation was increased at this locus with Kdm5b depletion in differentiating adult NSCs. Combined the data suggest Kdm5b negatively regulates neurogenesis and represses Reln in neural stem cells from the adult SVZ. PMID:26739753

  1. A comparison of long-term survivors and short-term survivors with glioblastoma, subventricular zone involvement: a predictive factor for survival?

    International Nuclear Information System (INIS)

    Long-term survival is rare in patients with glioblastoma (GBM). We set out to determine prognostic factors for patients with favorable and poor prognosis in regard of tumor localization to the subventricular zone (SZV). We reviewed the clinical records, pre-operative and post-operative MRI imaging of 50 LTS long-term survivors (LTS) (> 3 years) and 50 short-term survivors (STS) (< 1 year) with glioblastoma. These groups were matched for clinical characteristics being consistently associated with prolonged or shortened survival. All patients had undergone initial surgery or biopsy to confirm GBM diagnosis followed by radio- or chemoradiotherapy. LTS had a median progression-free survival PFS of 25, 4 months (2, 3–97, 8 months) and overall-survival (OS) of 55, 9 months (38, 2-98, 6 months) compared to STS who had a significantly lower PFS of 4, 2 months (1, 4–10, 2 months) and OS of 6, 6 months (2, 2–11, 6 months) (each p < 0,001). Survival analysis showed that age under 60 years (p < 0,001), total resection status (p < 0,001) and tumor localization without SVZ contact (p = 0,05) were significant factors for prolonged survival. Our findings underline that survival in GBM patients is heterogeneous and influenced by multiple factors. This study confirms that tumor location with regard to the SVZ is significantly associated with survival

  2. Distinct effects of pramipexole on the proliferation of adult mouse sub-ventricular zone-derived cells and the appearance of a neuronal phenotype.

    Science.gov (United States)

    Merlo, Sara; Canonico, Pier Luigi; Sortino, Maria Angela

    2011-05-01

    Pramipexole (PPX) is a dopamine agonist with an 8-fold higher affinity for D3 than D2 receptor, whose efficacy in the treatment of Parkinson's disease is based on dopamine agonistic activity. PPX has also been recently shown to be endowed with neuroprotective activity and neurogenic potential. The aim of this study was a more detailed characterization of PPX-induced neurogenesis. Both D2 and D3 receptors are expressed in floating and differentiated neurospheres obtained from the sub-ventricular zone (SVZ) of adult mice. Treatment of secondary neurospheres with 10 μM PPX causes a marked induction of cell proliferation, assessed by enhanced cell number and S phase population at cell cycle analysis. Stimulation of proliferation by PPX is still detectable in plated neurospheres before the onset of migration and differentiation, as by enhanced BrdU incorporation. This effect is sensitive to the selective D3 dopamine receptor antagonist U99194A, as well as to sulpiride. A 24 h treatment with PPX does not modify the morphology of neurosphere-derived cells, but causes an increase of glial fibrillary acidic protein (GFAP)-positive cells, an effect sensitive to both D2 and D3 antagonism. Differentiation toward the neuronal lineage is increased by PPX as shown by enhancement of the cell population positive to the early neuronal marker doublecortin (DCX) at 24 h and the mature neuronal marker microtubule associated protein (MAP2) at 72 h. This effect is not modified by treatment with U99194A and is mimicked by BDNF. Accordingly, PPX increases BDNF release with a mechanism involving D2 but not D3 receptors. PMID:21272591

  3. Novel in vivo imaging techniques for trafficking the behavior of subventricular zone neural stem cells (SVZSC) and SVZSC induced functional repair

    Energy Technology Data Exchange (ETDEWEB)

    Anna-Liisa Brownell

    2003-11-28

    Adult progenitor cells hold promise for therapeutic treatment where there has been a disabling loss of function due to death of cells from trauma, disease or aging. However, it will be essential in clinical application to be able to follow the fate of the transplanted cells over time using in vivo tracking methods. We have developed protocol for labeling of progenitor cells to monitor cell trafficking by high resolution magnetic resonance imaging (MRI) and super high resolution positron emission tomography (PET). We have transfected rat subventricular zone stem cells (SVZ, progenitor cell line) and another control cell line (PC12, pheochromocytoma cells) utilizing super paramagnetic iron oxide and poly-L-lysine complex for MR imaging or radiolabeling with 18F-fluor deoxy-D- glucose for PET imaging. The labeled cells were transplanted into the rostral migratory stream (RMS) or striatum of normal or 6-hydroxydopamine lesioned Spraque-Dawley rats. Longitudinal MRI studies (up to 40 days) showed that transplantation site has significant impact to the fate of the cells; when SVZ cells were transplanted into the RMS, cells migrated several centimeter into the olfactory bulb; after transplantation into the striatum, the migration was minimal, only 2 mm. PC 12 cells grew a massive tumor after the striatal implantation and significantly smaller tumor after the RMS implantation. PET studies conducted immediately after transplantation verified the transplantation site. MRI studies were able to show the whole path of migration in one image, since part of the cells die during migration and will get detected because of iron content. Endpoint histological studies verified the cell survival and immunohistochemical studies revealed the differentiation of the transplanted cells into astrocytes and neurons.

  4. Hard-diet feeding recovers neurogenesis in the subventricular zone and olfactory functions of mice impaired by soft-diet feeding.

    Science.gov (United States)

    Utsugi, Chizuru; Miyazono, Sadaharu; Osada, Kazumi; Sasajima, Hitoshi; Noguchi, Tomohiro; Matsuda, Mitsuyoshi; Kashiwayanagi, Makoto

    2014-01-01

    The subventricular zone (SVZ) generates an immense number of neurons even during adulthood. These neurons migrate to the olfactory bulb (OB) and differentiate into granule cells and periglomerular cells. The information broadcast by general odorants is received by the olfactory sensory neurons and transmitted to the OB. Recent studies have shown that a reduction of mastication impairs both neurogenesis in the hippocampus and brain functions. To examine these effects, we first measured the difference in Fos-immunoreactivity (Fos-ir) at the principal sensory trigeminal nucleus (Pr5), which receives intraoral touch information via the trigeminal nerve, when female adult mice ingested a hard or soft diet to explore whether soft-diet feeding could mimic impaired mastication. Ingestion of a hard diet induced greater expression of Fos-ir cells at the Pr5 than did a soft diet or no diet. Bromodeoxyuridine-immunoreactive (BrdU-ir) structures in sagittal sections of the SVZ and in the OB of mice fed a soft or hard diet were studied to explore the effects of changes in mastication on newly generated neurons. After 1 month, the density of BrdU-ir cells in the SVZ and OB was lower in the soft-diet-fed mice than in the hard-diet-fed mice. The odor preferences of individual female mice to butyric acid were tested in a Y-maze apparatus. Avoidance of butyric acid was reduced by the soft-diet feeding. We then explored the effects of the hard-diet feeding on olfactory functions and neurogenesis in the SVZ of mice impaired by soft-diet feeding. At 3 months of hard-diet feeding, avoidance of butyric acid was reversed and responses to odors and neurogenesis were recovered in the SVZ. The present results suggest that feeding with a hard diet improves neurogenesis in the SVZ, which in turn enhances olfactory function at the OB.

  5. Hard-diet feeding recovers neurogenesis in the subventricular zone and olfactory functions of mice impaired by soft-diet feeding.

    Directory of Open Access Journals (Sweden)

    Chizuru Utsugi

    Full Text Available The subventricular zone (SVZ generates an immense number of neurons even during adulthood. These neurons migrate to the olfactory bulb (OB and differentiate into granule cells and periglomerular cells. The information broadcast by general odorants is received by the olfactory sensory neurons and transmitted to the OB. Recent studies have shown that a reduction of mastication impairs both neurogenesis in the hippocampus and brain functions. To examine these effects, we first measured the difference in Fos-immunoreactivity (Fos-ir at the principal sensory trigeminal nucleus (Pr5, which receives intraoral touch information via the trigeminal nerve, when female adult mice ingested a hard or soft diet to explore whether soft-diet feeding could mimic impaired mastication. Ingestion of a hard diet induced greater expression of Fos-ir cells at the Pr5 than did a soft diet or no diet. Bromodeoxyuridine-immunoreactive (BrdU-ir structures in sagittal sections of the SVZ and in the OB of mice fed a soft or hard diet were studied to explore the effects of changes in mastication on newly generated neurons. After 1 month, the density of BrdU-ir cells in the SVZ and OB was lower in the soft-diet-fed mice than in the hard-diet-fed mice. The odor preferences of individual female mice to butyric acid were tested in a Y-maze apparatus. Avoidance of butyric acid was reduced by the soft-diet feeding. We then explored the effects of the hard-diet feeding on olfactory functions and neurogenesis in the SVZ of mice impaired by soft-diet feeding. At 3 months of hard-diet feeding, avoidance of butyric acid was reversed and responses to odors and neurogenesis were recovered in the SVZ. The present results suggest that feeding with a hard diet improves neurogenesis in the SVZ, which in turn enhances olfactory function at the OB.

  6. Novel in vivo imaging techniques for trafficking the behavior of subventricular zone neural stem cells (SVZSC) and SVZSC induced functional repair

    International Nuclear Information System (INIS)

    Adult progenitor cells hold promise for therapeutic treatment where there has been a disabling loss of function due to death of cells from trauma, disease or aging. However, it will be essential in clinical application to be able to follow the fate of the transplanted cells over time using in vivo tracking methods. We have developed protocol for labeling of progenitor cells to monitor cell trafficking by high resolution magnetic resonance imaging (MRI) and super high resolution positron emission tomography (PET). We have transfected rat subventricular zone stem cells (SVZ, progenitor cell line) and another control cell line (PC12, pheochromocytoma cells) utilizing super paramagnetic iron oxide and poly-L-lysine complex for MR imaging or radiolabeling with 18F-fluor deoxy-D- glucose for PET imaging. The labeled cells were transplanted into the rostral migratory stream (RMS) or striatum of normal or 6-hydroxydopamine lesioned Spraque-Dawley rats. Longitudinal MRI studies (up to 40 days) showed that transplantation site has significant impact to the fate of the cells; when SVZ cells were transplanted into the RMS, cells migrated several centimeter into the olfactory bulb; after transplantation into the striatum, the migration was minimal, only 2 mm. PC 12 cells grew a massive tumor after the striatal implantation and significantly smaller tumor after the RMS implantation. PET studies conducted immediately after transplantation verified the transplantation site. MRI studies were able to show the whole path of migration in one image, since part of the cells die during migration and will get detected because of iron content. Endpoint histological studies verified the cell survival and immunohistochemical studies revealed the differentiation of the transplanted cells into astrocytes and neurons

  7. MicroRNA profiling in subventricular zone after stroke: MiR-124a regulates proliferation of neural progenitor cells through Notch signaling pathway.

    Directory of Open Access Journals (Sweden)

    Xian Shuang Liu

    Full Text Available BACKGROUND: The Notch signaling pathway regulates adult neurogenesis under physiological and pathophysiological conditions. MicroRNAs are small non-coding RNA molecules that regulate gene expression. The present study investigated the effect of miR-124a on the Notch signaling pathway in stroke-induced neurogenesis. METHODOLOGY AND PRINCIPAL FINDINGS: We found that adult rats subjected to focal cerebral ischemia exhibited substantial reduction of miR-124a expression, a neuron specific miRNA, in the neural progenitor cells of the subventricular zone (SVZ of the lateral ventricle, which was inversely associated with activation of Notch signals. In vitro, transfection of neural progenitor cells harvested from the SVZ of adult rat with miR-124a repressed Jagged-1 (JAG1, a ligand of Notch, in a luciferase construct containing the JAG1 target site. Introduction of miR-124a in neural progenitor cells significantly reduced JAG1 transcript and protein levels, leading to inactivation of Notch signals. Transfection of neural progenitor cells with miR-124a significantly reduced progenitor cell proliferation and promoted neuronal differentiation measured by an increase in the number of Doublecortin positive cells, a marker of neuroblasts. Furthermore, introduction of miR-124a significantly increased p27Kip1 mRNA and protein levels, a downstream target gene of the Notch signaling pathway. CONCLUSIONS: Collectively, our study demonstrated that in vivo, stroke alters miRNA expression in SVZ neural progenitor cells and that in vitro, miR-124a mediates stroke-induced neurogenesis by targeting the JAG-Notch signaling pathway.

  8. Intranasal delivery of transforming growth factor-beta1 in mice after stroke reduces infarct volume and increases neurogenesis in the subventricular zone

    Directory of Open Access Journals (Sweden)

    Xu Gelin

    2008-12-01

    Full Text Available Abstract Background The effect of neurotrophic factors in enhancing stroke-induced neurogenesis in the adult subventricular zone (SVZ is limited by their poor blood-brain barrier (BBB permeability. Intranasal administration is a noninvasive and valid method for delivery of neuropeptides into the brain, to bypass the BBB. We investigated the effect of treatment with intranasal transforming growth factor-β1 (TGF-β1 on neurogenesis in the adult mouse SVZ following focal ischemia. The modified Neurological Severity Scores (NSS test was used to evaluate neurological function, and infarct volumes were determined from hematoxylin-stained sections. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL labeling was performed at 7 days after middle cerebral artery occlusion (MCAO. Immunohistochemistry was used to detect bromodeoxyuridine (BrdU and neuron- or glia-specific markers for identifying neurogenesis in the SVZ at 7, 14, 21, 28 days after MCAO. Results Intranasal treatment of TGF-β1 shows significant improvement in neurological function and reduction of infarct volume compared with control animals. TGF-β1 treated mice had significantly less TUNEL-positive cells in the ipsilateral striatum than that in control groups. The number of BrdU-incorporated cells in the SVZ and striatum was significantly increased in the TGF-β1 treated group compared with control animals at each time point. In addition, numbers of BrdU- labeled cells coexpressed with the migrating neuroblast marker doublecortin (DCX and the mature neuronal marker neuronal nuclei (NeuN were significantly increased after intranasal delivery of TGF-β1, while only a few BrdU labeled cells co-stained with glial fibrillary acidic protein (GFAP. Conclusion Intranasal administration of TGF-β1 reduces infarct volume, improves functional recovery and enhances neurogenesis in mice after stroke. Intranasal TGF-β1 may have therapeutic potential for cerebrovascular

  9. Increased doublecortin (DCX expression and incidence of DCX-immunoreactive multipolar cells in the subventricular zone-olfactory bulb system of suicides

    Directory of Open Access Journals (Sweden)

    Marissa E Maheu

    2015-06-01

    Full Text Available Postmortem studies have confirmed the occurrence of adult hippocampal neurogenesis in humans and implicated this process in antidepressant response, yet neurogenesis in other regions remains to be examined in the context of depression. Here we assess the extent of subventricular zone-olfactory bulb (SVZ-OB neurogenesis in adult humans having died by suicide. Protein expression of proliferative and neurogenic markers Sox2, proliferating cell nuclear antigen, and doublecortin (DCX were examined in postmortem SVZ and OB samples from depressed suicides and matched sudden-death controls. In the SVZ, DCX-immunoreactive (IR cells displayed phenotypes typical of progenitors, whereas in the olfactory tract (OT, they were multipolar with variable size and morphologies suggestive of differentiating cells. DCX expression was significantly increased in the OB of suicides, whereas SVZ DCX expression was higher among unmedicated, but not antidepressant-treated, suicides. Although very few DCX-IR cells were present in the control OT, they were considerably more common in suicides and correlated with OB DCX levels. Suicides also displayed higher DCX-IR process volumes. These results support the notion that OB neurogenesis is minimal in adult humans. They further indicate that the differentiation and migration of SVZ-derived neuroblasts may be altered in unmedicated suicides, leading to an accumulation of ectopically-differentiating cells in the OT. Normal SVZ DCX expression among suicides receiving antidepressants suggests a potentially novel mode of action of antidepressant medication. Given the modest group sizes and rarity of DCX-IR cells assessed here, a larger-scale characterization will be required before firm conclusions can be made regarding the identity of these cells.

  10. Conical expansion of the outer subventricular zone and the role of neocortical folding in evolution and development

    Directory of Open Access Journals (Sweden)

    Eric eLewitus

    2013-08-01

    Full Text Available There is a basic rule to mammalian neocortical expansion: as it expands, so does it fold. The degree to which it folds, however, cannot strictly be attributed to its expansion. Across species, cortical volume does not keep pace with cortical surface area, but rather folds appear more rapidly than expected. As a result, larger brains quickly become disproportionately more convoluted than smaller brains. Both the absence (lissencephaly and presence (gyrencephaly of cortical folds is observed in all mammalian orders and, while there is likely some phylogenetic signature to the evolutionary appearance of gyri and sulci, there are undoubtedly universal trends to the acquisition of folds in an expanding neocortex. Whether these trends are governed by conical expansion of neocortical germinal zones, the distribution of cortical connectivity, or a combination of growth- and connectivity-driven forces remains an open question. But the importance of cortical folding for evolution of the uniquely mammalian neocortex, as well as for the incidence of neuropathologies in humans, is undisputed. In this hypothesis and theory article, we will summarize the development of cortical folds in the neocortex, consider the relative influence of growth- versus connectivity-driven forces for the acquisition of cortical folds between and within species, assess the genetic, cell-biological, and mechanistic implications for neocortical expansion, and discuss the significance of these implications for human evolution, development, and disease. We will argue that evolutionary increases in the density of neuron production, achieved via maintenance of a basal proliferative niche in the neocortical germinal zones, drive the conical migration of neurons towards the cortical surface and ultimately lead to the establishment of cortical folds in large-brained mammal species.

  11. Age-Dependent Increase of Brain Copper Levels and Expressions of Copper Regulatory Proteins in the Subventricular Zone and Choroid Plexus

    Directory of Open Access Journals (Sweden)

    Sherleen eFu

    2015-06-01

    Full Text Available Our recent data suggest a high accumulation of Cu in the subventricular zone (SVZ along the wall of brain ventricles. Anatomically, SVZ is in direct contact with cerebrospinal fluid (CSF, which is secreted by a neighboring tissue choroid plexus. Changes in Cu regulatory gene expressions in the SVZ and choroid plexus as the function of aging may determine Cu levels in the CSF and SVZ. This study was designed to investigate associations between age, Cu levels, and Cu regulatory genes in SVZ and plexus. The SVZ and choroid plexus were dissected from brains of 3-week, 10-week or 9-month old male rats. Analyses by atomic absorption spectroscopy revealed that the SVZ of adult and old animals contained the highest Cu level compared with other tested brain regions. Significant positive correlations between age and Cu levels in SVZ and plexus were observed; the SVZ Cu level of old animals was 7.5- and 5.8-fold higher than those of young and adult rats (p<0.01, respectively. Quantitation by qPCR of the transcriptional expressions of Cu regulatory proteins showed that the SVZ expressed the highest level of Cu storage protein MTs, while the choroid plexus expressed the high level of Cu transporter protein Ctr1. Noticeably, Cu levels in the SVZ were positively associated with type B slow proliferating cell marker Gfap (p<0.05, but inversely associated with type A proliferating neuroblast marker Dcx (p<0.05 and type C transit amplifying progenitor marker Nestin (p<0.01. Dmt1 had significant positive correlations with age and Cu levels in the plexus (p<0.01. These findings suggest that Cu levels in all tested brain regions are increased as the function of age. The SVZ shows a different expression pattern of Cu-regulatory genes from the choroid plexus. The age-related increase of MTs and decrease of Ctr1 may contribute to the high Cu level in this neurogenesis active brain region.

  12. Studying the Integration of Adult-born Neurons

    OpenAIRE

    Gu, Yan; Janoschka, Stephen; Ge, Shaoyu

    2011-01-01

    Neurogenesis occurs in adult mammalian brains in the sub-ventricular zone (SVZ) of the lateral ventricle and in the sub-granular zone (SGZ) of the hippocampal dentate gyrus throughout life. Previous reports have shown that adult hippocampal neurogenesis is associated with diverse brain disorders, including epilepsy, schizophrenia, depression and anxiety (1). Deciphering the process of normal and aberrant adult-born neuron integration may shed light on the etiology of these diseases and inform...

  13. The functional significance of newly born neurons integrated into olfactory bulb circuits

    OpenAIRE

    Sakamoto, Masayuki; Kageyama, Ryoichiro; Imayoshi, Itaru

    2014-01-01

    The olfactory bulb (OB) is the first central processing center for olfactory information connecting with higher areas in the brain, and this neuronal circuitry mediates a variety of odor-evoked behavioral responses. In the adult mammalian brain, continuous neurogenesis occurs in two restricted regions, the subventricular zone (SVZ) of the lateral ventricle and the hippocampal dentate gyrus. New neurons born in the SVZ migrate through the rostral migratory stream and are integrated into the ne...

  14. Multimodal imaging of subventricular zone neural stem/progenitor cells in the cuprizone mouse model reveals increased neurogenic potential for the olfactory bulb pathway, but no contribution to remyelination of the corpus callosum.

    Science.gov (United States)

    Guglielmetti, Caroline; Praet, Jelle; Rangarajan, Janaki Raman; Vreys, Ruth; De Vocht, Nathalie; Maes, Frederik; Verhoye, Marleen; Ponsaerts, Peter; Van der Linden, Annemie

    2014-02-01

    Multiple sclerosis is a devastating demyelinating disease of the central nervous system (CNS) in which endogenous remyelination, and thus recovery, often fails. Although the cuprizone mouse model allowed elucidation of many molecular factors governing remyelination, currently very little is known about the spatial origin of the oligodendrocyte progenitor cells that initiate remyelination in this model. Therefore, we here investigated in this model whether subventricular zone (SVZ) neural stem/progenitor cells (NSPCs) contribute to remyelination of the splenium following cuprizone-induced demyelination. Experimentally, from the day of in situ NSPC labeling, C57BL/6J mice were fed a 0.2% cuprizone diet during a 4-week period and then left to recover on a normal diet for 8weeks. Two in situ labeling strategies were employed: (i) NSPCs were labeled by intraventricular injection of micron-sized iron oxide particles and then followed up longitudinally by means of magnetic resonance imaging (MRI), and (ii) SVZ NSPCs were transduced with a lentiviral vector encoding the eGFP and Luciferase reporter proteins for longitudinal monitoring by means of in vivo bioluminescence imaging (BLI). In contrast to preceding suggestions, no migration of SVZ NSPC towards the demyelinated splenium was observed using both MRI and BLI, and further validated by histological analysis, thereby demonstrating that SVZ NSPCs are unable to contribute directly to remyelination of the splenium in the cuprizone model. Interestingly, using longitudinal BLI analysis and confirmed by histological analysis, an increased migration of SVZ NSPC-derived neuroblasts towards the olfactory bulb was observed following cuprizone treatment, indicative for a potential link between CNS inflammation and increased neurogenesis.

  15. Mosaic Subventricular Origins of Forebrain Oligodendrogenesis.

    Science.gov (United States)

    Azim, Kasum; Berninger, Benedikt; Raineteau, Olivier

    2016-01-01

    In the perinatal as well as the adult CNS, the subventricular zone (SVZ) of the forebrain is the largest and most active source of neural stem cells (NSCs) that generates neurons and oligodendrocytes (OLs), the myelin forming cells of the CNS. Recent advances in the field are beginning to shed light regarding SVZ heterogeneity, with the existence of spatially segregated microdomains that are intrinsically biased to generate phenotypically distinct neuronal populations. Although most research has focused on this regionalization in the context of neurogenesis, newer findings underline that this also applies for the genesis of OLs under the control of specific patterning molecules. In this mini review, we discuss the origins as well as the mechanisms that induce and maintain SVZ regionalization. These come in the flavor of specific signaling ligands and subsequent initiation of transcriptional networks that provide a basis for subdividing the SVZ into distinct lineage-specific microdomains. We further emphasize canonical Wnts and FGF2 as essential signaling pathways for the regional genesis of OL progenitors from NSCs of the dorsal SVZ. This aspect of NSC biology, which has so far received little attention, may unveil new avenues for appropriately recruiting NSCs in demyelinating diseases. PMID:27047329

  16. Mosaic subventricular origins of forebrain oligodendroglia

    Directory of Open Access Journals (Sweden)

    Kasum eAzim

    2016-03-01

    Full Text Available In the perinatal as well as the adult CNS, the subventricular zone (SVZ of the forebrain is the largest and most active source of neural stem cells (NSCs that generates neurons and oligodendrocytes (OLs, the myelin forming cells of the CNS. Recent advances in the field are beginning to shed light regarding SVZ heterogeneity, with the existence of spatially segregated microdomains that are intrinsically biased to generate phenotypically distinct neuronal populations. Although most research has focused on this regionalization in the context of neurogenesis, newer findings underline that this also applies for the genesis of OLs under the control of specific patterning molecules. In this mini review, we discuss the origins as well as the mechanisms that induce and maintain SVZ regionalization. These come in the flavor of specific signaling ligands and subsequent initiation of transcriptional networks that provide a basis for subdividing the SVZ into distinct lineage-specific microdomains. We further emphasize canonical Wnt and FGF2 as essential signaling pathways for the regional genesis of OL progenitors from NSCs of the dorsal SVZ. This aspect of NSC biology, which has so far received little attention, may unveil new avenues for appropriately recruiting NSCs in demyelinating diseases.

  17. 缺氧缺血对人类胚胎脑室管膜下区神经细胞亚群的影响%Effects of hypoxia-ischemia on different neural cells in subventricular zone of human fetus

    Institute of Scientific and Technical Information of China (English)

    张燕舞; 陈燕惠

    2008-01-01

    higher survival rate than neurons and oligodendrocyte progenitors.%目的 研究缺氧缺血对妊娠中期人类胚胎脑室管膜下区(subventricular zone,SVZ)神经细胞亚群的影响.方法 取即刻解离的妊娠中期人类胚胎脑SVZ细胞,分缺氧缺血组(HI组)和对照组短时培养.以氧糖缺失法(OGD)制备缺氧缺血损伤细胞模型.培养前以细胞成活率评价损伤程度,培养后以细胞特异性标志蛋白nestin、MAP2、GFAP、PDGFRa及RCA120的抗体通过免疫荧光细胞化学法分别鉴定神经干细胞(NSCs)、神经元、星形胶质细胞、少突胶质祖细胞及小胶质细胞,比较其百分含量.结果 HI组的细胞成活率(63.41%±0.06%),明显低于正常组(98.9%±0.01%)(P<0.001),短时培养后HI组中细胞亚群中含量最高的是GFAP(+)的星形胶质细胞56.48%±0.03%,其次为神经干细胞NSCs 22.47%±0.03%而PDGFRa(+)的少突胶质祖细胞含量最低;在对照组中最高则为MAP2(+)的神经元48.81%±0.03%,其次为GFAP(+)的星形胶质细胞32.31%±0.03%.含量最少的为小胶质细胞1.15%±0.01%.结论 妊娠中期人类胚胎脑SVZ含有NSCs、神经元、星形胶质细胞、少突胶质祖细胞和小胶质细胞,缺氧缺血对SVZ神经细胞损伤明显,不同细胞对缺氧缺血损伤的耐受性不同:NSCs、星形胶质细胞对缺氧缺血损伤的耐受性相对强于神经元、少突胶质祖细胞.

  18. Iatrogenic Blood-borne Viral Infections in Refugee Children from War and Transition Zones

    OpenAIRE

    Goldwater, Paul N.

    2013-01-01

    Pediatric infectious disease clinicians in industrialized countries may encounter iatrogenically transmitted HIV, hepatitis B virus, and hepatitis C virus infections in refugee children from Central Asia, Southeast Asia, and sub-Saharan Africa. The consequences of political collapse and/or civil war—work migration, prostitution, intravenous drug use, defective public health resources, and poor access to good medical care—all contribute to the spread of blood-borne viruses. Inadequate infectio...

  19. Analysis of space-borne data for coastal zone information extraction of Goa Coast, India

    Digital Repository Service at National Institute of Oceanography (India)

    Kunte, P.D.; Wagle, B.G.

    coastal zone, which may have long-term economic consequences. Interactions between various natural processes and man-made activities are important factors in the coastal area. Marine scientists and coastal engineers recognize the coastal zone as a... ~" 1_1_1 0 2 Km ~ART Laterite mesas m Wave-cut terraces I~ Exposed rock Inselberg 1]dal river River terraces cliff "tidal flat ~1 Old tidal flat [~] Channel bar Beach Active dunes Stabilized dunes I~ Beach ridges I Salt...

  20. The prevalence of serum antibodies to tick-borne infections in Mbale District, Uganda: the effect of agro-ecological zone, grazing management and age of cattle.

    Science.gov (United States)

    Rubaire-Akiiki, C; Okello-Onen, J; Nasinyama, G W; Vaarst, M; Kabagambe, E K; Mwayi, W; Musunga, D; Wandukwa, W

    2004-01-01

    Between August and October 2000, a cross-sectional study was conducted in smallholder dairy farms in Mbale District, Uganda to assess the prevalence of ticks and tick-borne diseases under different grazing systems and agro-ecological zones and understand the circumstances under which farmers operated. A questionnaire was administered to obtain information on dairy farm circumstances and practices. A total of 102 farms were visited and sera and ticks were collected from 478 animals. Sero-prevalence of tick-borne diseases was determined using an enzyme-linked immunoassay. Acaricides were used indiscriminately but the intensity of their use varied with the grazing system and zone. Cattle from different farms mixed for various reasons. During the dry seasons farmers have to get additional fodder from outside their farms that can result in importation of ticks. The prevalence of ticks and serum antibodies to tick-borne infections differed across the grazing systems and zones. The highest serum antibody prevalence (>60%) was recorded in the lowland zone under the free range and tethering grazing systems. The lowest tick challenge and serum antibody levels (<50%) were recorded in the midland and upland zones under a zero-grazing system. These findings suggest that endemic stability to East Coast Fever, babesiosis and anaplasmosis is most likely to have existed in the lowland zone, particularly, under the tethering and free-range grazing systems. Also, endemic stability for babesiosis existed in the upland zones. Endemic instability for East Coast Fever existed in the midland and upland zones. These structured observational studies are instrumental in planning of control strategies for ticks and tick borne diseases since production systems and the cattle population at high risk of the diseases in the district have been identified. PMID:15861224

  1. The prevalence of serum antibodies to tick-borne infections in Mbale District, Uganda: The effect of agro-ecological zone, grazing management and age of cattle

    Directory of Open Access Journals (Sweden)

    C. Rubaire-Akiiki

    2004-03-01

    Full Text Available Between August and October 2000, a cross-sectional study was conducted in smallholder dairy farms in Mbale District, Uganda to assess the prevalence of ticks and tick-borne diseases under different grazing systems and agro-ecological zones and understand the circumstances under which farmers operated. A questionnaire was administered to obtain information on dairy farm circumstances and practices. A total of 102 farms were visited and sera and ticks were collected from 478 animals. Sero-prevalence of tick-borne diseases was determined using an enzyme-linked immunoassay. Acaricides were used indiscriminately but the intensity of their use varied with the grazing system and zone. Cattle from different farms mixed for various reasons. During the dry seasons farmers have to get additional fodder from outside their farms that can result in importation of ticks. The prevalence of ticks and serum antibodies to tick-borne infections differed across the grazing systems and zones. The highest serum antibody prevalence (>60% was recorded in the lowland zone under the free range and tethering grazing systems. The lowest tick challenge and serum antibody levels (<50% were recorded in the midland and upland zones under a zero-grazing system. These findings suggest that endemic stability to East Coast Fever, babesiosis and anaplasmosis is most likely to have existed in the lowland zone, particularly, under the tethering and free-range grazing systems. Also, endemic stability for babesiosis existed in the upland zones. Endemic instability for East Coast Fever existed in the midland and upland zones. These structured observational studies are instrumental in planning of control strategies for ticks and tick borne diseases since production systems and the cattle population at high risk of the diseases in the district have been identified.

  2. Urban Market Gardening and Rodent-Borne Pathogenic Leptospira in Arid Zones: A Case Study in Niamey, Niger.

    Directory of Open Access Journals (Sweden)

    Gauthier Dobigny

    Full Text Available Leptospirosis essentially affects human following contact with rodent urine-contaminated water. As such, it was mainly found associated with rice culture, recreational activities and flooding. This is also the reason why it has mainly been investigated in temperate as well as warm and humid regions, while arid zones have been only very occasionally monitored for this disease. In particular, data for West African countries are extremely scarce. Here, we took advantage of an extensive survey of urban rodents in Niamey, Niger, in order to look for rodent-borne pathogenic Leptospira species presence and distribution across the city. To do so, we used high throughput bacterial 16S-based metabarcoding, lipL32 gene-targeting RT-PCR, rrs gene sequencing and VNTR typing as well as GIS-based multivariate spatial analysis. Our results show that leptospires seem absent from the core city where usual Leptospira reservoir rodent species (namely R. rattus and M. natalensis are yet abundant. On the contrary, L. kirschneri was detected in Arvicanthis niloticus and Cricetomys gambianus, two rodent species that are restricted to irrigated cultures within the city. Moreover, the VNTR profiles showed that rodent-borne leptospires in Niamey belong to previously undescribed serovars. Altogether, our study points towards the importance of market gardening in maintain and circulation of leptospirosis within Sahelian cities. In Africa, irrigated urban agriculture constitutes a pivotal source of food supply, especially in the context of the ongoing extensive urbanization of the continent. With this in mind, we speculate that leptospirosis may represent a zoonotic disease of concern also in arid regions that would deserve to be more rigorously surveyed, especially in urban agricultural settings.

  3. Urban Market Gardening and Rodent-Borne Pathogenic Leptospira in Arid Zones: A Case Study in Niamey, Niger.

    Science.gov (United States)

    Dobigny, Gauthier; Garba, Madougou; Tatard, Caroline; Loiseau, Anne; Galan, Max; Kadaouré, Ibrahima; Rossi, Jean-Pierre; Picardeau, Mathieu; Bertherat, Eric

    2015-01-01

    Leptospirosis essentially affects human following contact with rodent urine-contaminated water. As such, it was mainly found associated with rice culture, recreational activities and flooding. This is also the reason why it has mainly been investigated in temperate as well as warm and humid regions, while arid zones have been only very occasionally monitored for this disease. In particular, data for West African countries are extremely scarce. Here, we took advantage of an extensive survey of urban rodents in Niamey, Niger, in order to look for rodent-borne pathogenic Leptospira species presence and distribution across the city. To do so, we used high throughput bacterial 16S-based metabarcoding, lipL32 gene-targeting RT-PCR, rrs gene sequencing and VNTR typing as well as GIS-based multivariate spatial analysis. Our results show that leptospires seem absent from the core city where usual Leptospira reservoir rodent species (namely R. rattus and M. natalensis) are yet abundant. On the contrary, L. kirschneri was detected in Arvicanthis niloticus and Cricetomys gambianus, two rodent species that are restricted to irrigated cultures within the city. Moreover, the VNTR profiles showed that rodent-borne leptospires in Niamey belong to previously undescribed serovars. Altogether, our study points towards the importance of market gardening in maintain and circulation of leptospirosis within Sahelian cities. In Africa, irrigated urban agriculture constitutes a pivotal source of food supply, especially in the context of the ongoing extensive urbanization of the continent. With this in mind, we speculate that leptospirosis may represent a zoonotic disease of concern also in arid regions that would deserve to be more rigorously surveyed, especially in urban agricultural settings. PMID:26437456

  4. Artesunate promotes proliferation of rat neural stem cells from subventricular zone via PI3K-Akt pathway in vitro%青蒿琥酯通过PI3K-Akt通路促进大鼠室管膜下区神经干细胞增殖的体外研究

    Institute of Scientific and Technical Information of China (English)

    葛红飞; 左世伦; 李强; 谭亮; 吴江怡; 蒋周阳; 喻安永; 兰川; 胡荣

    2015-01-01

    目的 探讨青蒿琥酯(artesunate,ART)对室管膜下区(subventricular zone,SVZ)神经干细胞(neural stem cells,NSCs)增殖的影响.方法 不同浓度的ART(400 nmol/L、800 nmol/L、1.6 μmol/L、3.2 μmol/L)作用于NSCs 24 h后,采用CCK-8法检测其对NSCs增殖的影响.促增殖作用明显的800 nmol/L ART组加入10 μmol/L PI3K-Akt通路阻断剂(LY294002),采用CCK-8法检测该通路对NSCs增殖的影响;分别设置空白对照组、LY294002组、800 nmol/L ART组、800 nmol/L ART+ LY294002组,待细胞培养24h时,行Ki-67免疫荧光染色观察ART对NSCs增殖的影响及PI3K-Akt通路在其中的作用,同时采用Western blot检测各组Nestin、Akt及p-Akt蛋白的表达水平.结果 ①CCK-8法检测结果显示800 nmol/L ART组在波长450 nm处的光密度值较空白对照组明显升高,在加入LY294002后,其光密度值明显下降(P<0.05),与空白对照组水平相当;②Ki-67免疫荧光染色结果提示800 nmol/L ART可促进NSCs增殖,LY294002可抑制这一作用;③Western blot检测结果显示:神经干细胞表面标志蛋白Nestin及p-Akt蛋白表达水平在800 nmol/L ART组明显上调,在加入LY294002后两者表达水平均下调(P<0.05).结论 ART可在体外促进SVZ区NSCs的增殖,其机制与PI3K-Akt信号通路相关.

  5. 联合地塞米松治疗与肺炎链球菌脑膜炎室管膜下区碱性成纤维细胞生长因子表达的关系%The relationship between dexamethasone and the expression of basic fibroblast growth factor in subventricular zone of experimental streptococcus pneumoniae meningitis

    Institute of Scientific and Technical Information of China (English)

    赵秀英; 李玲; 廖锋; 向伟

    2013-01-01

    Objective To investigate the relationship between dexamethasone (DEX) and the expression of basic fibroblast growth factor (bFGF) in subventricular zone (SVZ) of experimental streptococcus pneumoniae meningitis. Methods Forty 3-week-old rats were used to develop the model of streptococcus pneumoniae meningitis, and were randomly divided into 4 groups of 10 rats each, antibiotic group, antibiotic plus DEX group, infection control group and normal control group. The expression level of bFGF in SVZ was detected by immunohistochemical staining. Results The expression level of bFGF in SVZ of rats in antibiotic group was similar to that of rats in infection control group (P>O.05). However, the expression level of bFGF in SVZ of rats in antibiotic plus DEX group was significantly higher than that of rats in antibiotic group and infection control group (P<0.01). Conclusions In the course of streptococcus pneumoniae meningitis, the combination therapy of antibiotics and DEX can up-regulate the expression level of bFGF in SVZ, which may promote neurogenesis and protect against brain injury in bacterial meningitis.%目的 探讨联合地塞米松(DEX)治疗与肺炎链球菌脑膜炎脑生发区域-室管膜下区(SVZ)碱性成纤维细胞生长因子(bFGF)表达的关系.方法 40只3周龄大鼠建立肺炎链球菌脑膜炎模型,分为抗生素组、抗生素联合DEX组、感染对照组、正常对照组,每组10只.免疫组化检测脑组织bFGF的表达.结果 抗生素组大鼠SVZ中的bFGF表达与感染对照组差异无统计学意义(P>0.05),而使用抗生素联合DEX组大鼠bFGF表达高于抗生素治疗组及感染对照组,差异均有统计学意义(P<0.01).结论 在肺炎链球菌脑膜炎病程中,联合DEX治疗可以上调bFGF在SVZ中的表达,可能有利于其促进神经生发,有利于抵御细菌性脑膜炎脑损伤.

  6. The prevalence of serum antibodies to tick-borne infections in Mbale District, Uganda: The effect of agro-ecological zone, grazing management and age of cattle

    OpenAIRE

    Rubaire-Akiiki, C.; J.Okello-Onen; G.W. Nasinyama; Vaarst, M; Kabagambe, E. K.; W. Mwayi; Musunga, D.; Wandukwa, W.

    2004-01-01

    Between August and October 2000, a cross-sectional study was conducted in smallholder dairy farms in Mbale District, Uganda to assess the prevalence of ticks and tick-borne diseases under different grazing systems and agro-ecological zones and understand the circumstances under which farmers operated. A questionnaire was administered to obtain information on dairy farm circumstances and practices. A total of 102 farms were visited and sera and ticks were collected from 478 animals. Sero-preva...

  7. 蛋白酶体抑制剂MG132对脑室室管膜下区神经干细胞增殖潜能的影响%Effects of proteasome inhibitor MG132 on proliferation of neural stem cells in subventricular zone

    Institute of Scientific and Technical Information of China (English)

    赵云鹤; 张卫国; 朱茜; 杨桂姣; 陆利

    2011-01-01

    目的:观察侧脑室注射蛋白酶体抑制剂MG132对脑室室管膜下区(SVZ)神经干细胞(NSCs)增殖能力的影响,了解蛋白酶体对NSCs增殖潜能的调控作用,从而进一步探讨蛋白酶体在帕金森病(PD)等老年性疾病神经元损伤中的可能作用机制.方法:选90日龄健康BALB/c小鼠,左侧侧脑室注射10 μg MG132,于注射后3 d、7 d、14 d提取SVZ总蛋白,荧光酶标仪检测蛋白酶体活性.同时腹腔注射5-溴-2-脱氧尿嘧啶核苷(BrdU),BrdU免疫荧光染色标记NSCs,动态观察蛋白酶体活性改变对NSCs增殖能力的影响.另设溶剂对照组左侧侧脑室注射等剂量DMSO,进行上述实验.结果:侧脑室注射MG132 3 d、7 d后,SVZ蛋白酶体活性较DMSO对照组显著降低(P<0.05),同时SVZ BrdU+ NSCs也显著减少至21±4和22±3,与DMSO对照组相比差异显著(P<0.05).随着MG132注射时间延长,14 d后SVZ蛋白酶体活性恢复至正常水平(P>0.05),BrdU+ NSCs数量MG132组(82±4)与DMSO组(67±6)相比无显著差别(P>0.05).结论:应用蛋白酶体可逆性抑制剂MG132短时期内能显著抑制SVZ蛋白酶体活性,并且能够降低NSCs增殖能力,提示蛋白酶体活性与NSCs增殖潜能密切相关.%AIM: To investigate the role of proteasome in the degeneration of neuron in age - related diseases such as Parkinson disease ( PD ) by observing the effects of proteasome inhibitor MG132 on the proliferation of neural stem cells ( NSCs ) in the subventricular zone ( SVZ ).METHODS: Stereotaxic microinjection of proteasome inhibitor MG132 at a dose of 10 μg into the left lateral ventricle of 90 - day - old mice was performed.The control mice were received the same volume of DMSO into the left lateral ventricle.Three days, 7 days and 14 days after injection, the total proteins isolat from SVZ were subject to proteasome activity assay using the fluorescence microplate reader.Meanwhile, the mice were administered with 5 - bromo - 2' - deoxyuridine ( BrdU ) by

  8. Effects of N-methyl-D-aspartate Receptor Antagonist MK-801 on Expression of Glial Fibrillary Acidic Protein in the Subventricular Zone of Neonatal Rat%NMDA受体拮抗剂MK-801对新生大鼠室管膜下区胶质纤维酸性蛋白表达的影响

    Institute of Scientific and Technical Information of China (English)

    李晓泉; 陈芳芳; 王伟; 来青伟; 耿德勤; 樊红彬

    2013-01-01

    Aim To investigate the effects of the N-methyl-D-aspartate(NMDA)-receptor antagonist MK801 on the expression of glial fibrillary acidic protein(GFAP) in the subventricular zone(SVZ) of neonatal rat.Methods 40 neonatal SD rats were assigned into two groups,a MK-801 group and a control group.Each group was respectively divided into four time points,including P7 d (postnatal 7 days),P14 d,P21 d and P28 d.Rats in the experiment group were intraperitoneally injected selective non-competitive NMDA receptor antagonist MK-801 (10 mg·kg1),while rats in the control group were intraperitoneally injected saline.Immunohistochemical staining was used to assay the number of GFAP-positive cells in the SVZ.Results ① In the control group,the number of GFAP-positive cells increased at P14 d,and the number of GFAP-positive cells reached maximum at P21 d,positive cells decreased significantly at 28 d.② Compared with the control group,the number of GFAP-positive cells reduced significantly at P 14 d (65.40 ± 6.11) and P21 d (239.60 ± 12.92),and the number of GFAP-positive cells increased significantly [P14 d(79.20 ± 5.26),P21 d(265.20 ± 7.40)](P<0.01),while the number of positive cells without obvious changes at P7 d and P28 d in the MK-801 group.Conclusion NMDA-receptor antagonist MK-801 could reduce the expression of GFAP in the SVZ,and inhibit the neural stem cells proliferation and differentiation.%目的 研究N-甲基-D-天冬氨酸(NMDA)受体拮抗剂MK-801对新生7d大鼠室管膜下区(SVZ)胶质纤维酸性蛋白(GFAP)表达的影响.方法 将40只新生SD大鼠分成对照组和MK-801组,各组按出生后口(P)时间点再随机分成4个亚组:P7d、P14d、P21 d、P28d组.新生大鼠均于生后第3天给药,MK-801组腹腔注射MK-801 10 mg·kg-1;对照组腹腔注射同量生理盐水.通过免疫组化学方法观察大鼠SVZ区GFAP阳性细胞数.结果 ①对照组GFAP阳性细胞数于P14 d开始增加,至P21 d达最大值;但P28 d时阳

  9. Genetic Methods to Identify and Manipulate Newly born Neurons in the Adult Brain

    Directory of Open Access Journals (Sweden)

    Itaru eImayoshi

    2011-05-01

    Full Text Available Although mammalian neurogenesis is mostly completed by the perinatal period, new neurons are continuously generated in the subventricular zone of the lateral ventricle and the subgranular zone of the hippocampal dentate gyrus. Since the discovery of adult neurogenesis, many extensive studies have been performed on various aspects of adult neurogenesis, including proliferation and fate-specification of adult neural stem cells, and the migration, maturation and synaptic integration of newly born neurons. Furthermore, recent research has shed light on the intensive contribution of adult neurogenesis to olfactory-related and hippocampus-mediated brain functions. The field of adult neurogenesis progressed tremendously thanks to technical advances that facilitate the identification and selective manipulation of newly born neurons among billions of pre-existing neurons in the adult central nervous system. In this review, we introduce recent advances in the methodologies for visualizing newly generated neurons and manipulating neurogenesis in the adult brain. Particularly, the application of site-specific recombinases and Tet inducible system in combination with transgenic or gene targeting strategy is discussed in further detail.

  10. Urban market gardening and rodent-borne pathogenic leptospira in arid zones : a case study in Niamey, Niger

    OpenAIRE

    Gauthier Dobigny; Madougou Garba; Caroline Tatard; Anne Loiseau; Max Galan; Ibrahima Kadaouré; Jean-Pierre Rossi; Mathieu Picardeau; Eric Bertherat

    2015-01-01

    Leptospirosis essentially affects human following contact with rodent urine-contaminated water. As such, it was mainly found associated with rice culture, recreational activities and flooding. This is also the reason why it has mainly been investigated in temperate as well as warm and humid regions, while arid zones have been only very occasionally monitored for this disease. In particular, data for West African countries are extremely scarce. Here, we took advantage of an extensive survey of...

  11. U-Pb Zircon geochronology and Sr-Nd isotopic characteristic of Late Neo proterozoic Born award granitoids (Taknar zone exotic block), Iran

    International Nuclear Information System (INIS)

    The study area (Born award granite) is located in northeast of Iran (Khorasan Razavi province), about 280 km southwest of Mashhad city. Taknar zone is an exotic block, bordered by two major faults, Great Kavir fault (Drouneh) to the south and Rivash fault in the north. A complex of granite, granodiorite, monzonite and diorite crop out at the center of Taknar zone. They are named as Bornaward granite. Published data using Rb-Sr whole-rock and biotite isotopic methods on granitoid rocks (Born award granite) gave ages of 154 to 111 Ma. The results of U-Pb zircon dating of granodiorite is 552.69 ± 10.89 Ma and granite is 538.22 - 1.82, + 4.28 Ma (Late Neo proterozoic time). Both granite and granodiorite are classified as belonging to the ilmenite-series of reduced S-type granitoids. Chemically, they are per-aluminous, high-K calc-alkaline with relatively enriched in LILE, Rb, K and depleted in Sr, Ba, Nb, Ti, Ta, Y and Yb. Chondrite-normalized Rare Earth Element plots indicate minor enrichments of light Rare Earth Element in composition with heavy Rare Earth Element, with (La/Yb)N between 3.5-5.6 and high total Rare Earth Element (193-252) with strong negative anomaly of Eu. They have a initial 87Sr/86Sr and 143Nd/144Nd ranging from 0.713566 to 0.716888 and 0.511791 to 0.511842, respectively, when recalculated to an age of 553 and 538 Ma, consistent with the new radiometric results. Initial εNd isotope values for granite and granodiorite range from -2,62 to -2,01. Granite and granodiorite of Born award yields a TDM age of 1.4-1.41 Ga. This indicates that the granites and granodiorite being derived from partial melting of distinct basement source regions with very high initial 87Sr/86Sr.

  12. The dual function of the splenic marginal zone : essential for initiation of anti-TI-2 responses but also vital in the general first-line defense against blood-borne antigens

    NARCIS (Netherlands)

    Zandvoort, A; Timens, W

    2002-01-01

    The splenic marginal zone (S-MZ) is especially well equipped for rapid humoral responses and is unique in its ability to initiate an immune response to encapsulated bacteria (T-cell independent type 2 (TI-2) antigens). Because of the rapid spreading through the blood, infections with blood-borne bac

  13. The functional significance of newly born neurons integrated into olfactory bulb circuits

    Directory of Open Access Journals (Sweden)

    Masayuki eSakamoto

    2014-05-01

    Full Text Available The olfactory bulb (OB is the first central processing center for olfactory information connecting with higher areas in the brain, and this neuronal circuitry mediates a variety of odor-evoked behavioral responses. In the adult mammalian brain, continuous neurogenesis occurs in two restricted regions, the subventricular zone (SVZ of the lateral ventricle and the hippocampal dentate gyrus. New neurons born in the SVZ migrate through the rostral migratory stream and are integrated into the neuronal circuits of the OB throughout life. The significance of this continuous supply of new neurons in the OB has been implicated in plasticity and memory regulation. Two decades of huge investigation in adult neurogenesis revealed the biological importance of integration of new neurons into the olfactory circuits. In this review, we highlight the recent findings about the physiological functions of newly generated neurons in rodent OB circuits and then discuss the contribution of neurogenesis in the brain function. Finally, we introduce cutting edge technologies to monitor and manipulate the activity of new neurons.

  14. 离体培养的生后大鼠脑室下层神经元前体细胞免疫细胞化学和形态学研究%IMMUNOCYTOCHEMIICAL AND MORPHOMETRICAL STUDY OF THE NEURONAL PRECURSOR CELLS DERIVED FROM THE SUBVENTRICULAR ZONE OF THE POSTNATAL RAT FOREBRAIN IN VITRO

    Institute of Scientific and Technical Information of China (English)

    高殿帅; 张凤真; 王德广; 周长福

    2000-01-01

    In order to investigate the chemical and morphornetrical properties of the neuronal precursor cells derived from thesubventricular zone(SVZ) of the postnatal rat forebrain in vitro. The cell-type specific antibodies were used for the immunocy-tochemical staining ,and the morphometric parameters which were the mean soma diameter and the ellipticity index (i. e. , thesmallest soma diameter divided by the largest soma diameter) of every SVZ-derived cell were measured for identifying the pheno-types of the SVZ cells in vitro. The experiment animals were SD rats (weights: 100~ 150 g), the SVZ cells derived from thepostnatal rats were cultured on poly-D-lysine-coated 24-well glass chamber slides in the Neurobasal Medium supplemented withB27 in 5% CO2 at 37 C. The following results were obtained.. At 1 day in vitro, almost all SVZ cells (〉90%) from the postna-tal rat forebrain expressed Tujl, an antibody that recognizes neuron-specific tubulin. Likewise, the preponderance of the SVZcells expressed the polysialylated neural cell adhesion molecule (PSA-N-CAM) ; The majority of the SVZ Tujl-positive cells cul-tured were the cells that had oval-shaped bodies with two short, unbranched processes protruded from every two poles, theirmean soma diameter were 8.42±1.03μm and their ellipticity index were 0.57±0.12. Meanwhile, there were approximately20% of the SVZ cells in culture that were sphere-shaped cells with mean soma diameter 7.20±l.04 μm , and it might be observed that these cells connected with one another. As the time in culture went on, these sphere-shaped SVZ-derived cells alsotransformed to oval-shaped ones as described above, but it could be observed that the cells were still connected in the processesof them. By 3 and 5 days in culture, the SVZ cells had larger cell somas (average diameter 9. 07±1.07 μm), and often consider-ably longer processes but still with few branches. Immunocytochemical staining revealed that the majority of the SVZ cells in cul

  15. A Distinct Population of Microglia Supports Adult Neurogenesis in the Subventricular Zone

    DEFF Research Database (Denmark)

    Ribeiro Xavier, Anna L.; Kress, Benjamin T.; Goldman, Steven A.;

    2015-01-01

    that is selectively adapted to the support and direction of neuronal integration into the olfactory circuitry. Therefore, this unique microglial subpopulation may serve as a novel target with which to modulate cellular addition from endogenous neural stem and progenitor cells of the adult brain. SIGNIFICANCE...... STATEMENT: Microglial cells are a specialized population of macrophages in the CNS, playing key roles as immune mediators. As integral components in the CNS, the microglia stand out for using the same mechanisms, phagocytosis and cytochemokine release, to promote homeostasis, synaptic pruning, and neural...

  16. Characterization of Seeding Conditions for Studies on Differentiation Patterns of Subventricular Zone Derived Neurospheres

    OpenAIRE

    Sanchez-Mendoza, Eduardo H.; Schlechter, Jana; Hermann, Dirk M.; Doeppner, Thorsten R.

    2016-01-01

    Stem cell research depends on extensive in vitro research. Poly-D-lysine (PDL) and polyornithine (PornT) are chemically synthesized amino acid chains promoting cell adhesion to solid substrates. Although, PDL and PornT are extensively used, there is no common agreement regarding the most optimal substance and its concentration. We therefore aimed at testing the effect of increasing concentrations (10, 50, and 100 μg/ml) for each compound and their corresponding mixtures (5+5 and 10+10 μg/ml) ...

  17. Characterization of seeding conditions for studies on differentiation patterns of subventricular zone derived neurospheres

    OpenAIRE

    Sanchez-Mendoza, Eduardo H.; Jana eSchlechter; Dirk Matthias Hermann; Thorsten Roland Doeppner

    2016-01-01

    Stem cell research depends on extensive in vitro research. Poly-D-Lysine (PDL) and Polyornithine (PornT) are chemically synthesized amino acid chains promoting cell adhesion to solid substrates. Although PDL and PornT are extensively used, there is no common agreement regarding the most optimal substance and its concentration. We therefore aimed at testing the effect of increasing concentrations (10, 50 and 100 µg/ml) for each compound and their corresponding mixtures (5+5 and 10+10 µg/ml) on...

  18. EFFECTS OF CEREBRAL CORTICAL CONCIS ON CELL PROLIFERATION OF THE SUBVENTRICULAR ZONE IN ADULT RATS

    Institute of Scientific and Technical Information of China (English)

    Zhang Yuelin; Qiu Shudong; Zhang Pengbo; Shi Wei

    2006-01-01

    Objective To investigate the proliferative response and time course of endogenous neural stem/progenitor cells after cerebral cortical concis in the adult rats. Methods Eighty adult male Sprague-Dawley rats were used in this study. Cumulative BrdU labeling was employed to detect the proliferating cells. At 1 d, 3 d, 7 d, 14 d, and 21 d after cerebral cortical concis, the rats were killed for BrdU immunohistochemical staining and cell counting in the injured ipsilateral SVZ. Results Little BrdU immunoreactivity cells was present in SVZ of the control rats from day 7 to day 21 after sham operation. The number of BrdU immunoreactivity cells in the injured ipsilateral SVZ increased at day 1 and peaked at day 7 after cerebral cortical concis. Conclusion After cerebral cortical concis of the adult rats, neural stem/progenitor cells in the injured ipsilateral SVZ markedly proliferated with a peak at day 7. This finding may be important for manipulating SVZ cells to promote the recovery from cerebral cortical concis.

  19. Food-borne protozoa.

    Science.gov (United States)

    Nichols, G L

    2000-01-01

    Pathogenic protozoa are commonly transmitted to food in developing countries, but food-borne outbreaks of infection are relatively rare in developed countries. The main protozoa of concern in developed countries are Toxoplasma, Cryptosporidium and Giardia, and these can be a problem in immunocompromised people. Other protozoa such as Entamoeba histolytica, Cyclospora cayetanensis and Sarcocystis can be a food-borne problem in non-industrialised countries. C. cayetanensis has emerged as a food-borne pathogen in foods imported into North America from South America. Microsporidia may be food-borne, although evidence for this is not yet available. The measures needed to prevent food-borne protozoa causing disease require clear assessments of the risks of contamination and the effectiveness of processes to inactivate them. The globalisation of food production can allow new routes of transmission, and advances in diagnostic detection methods and surveillance systems have extended the range of protozoa that may be linked to food. PMID:10885117

  20. Depletion of neural stem cells from the subventricular zone of adult mouse brain using cytosine b‐Arabinofuranoside

    OpenAIRE

    Ghanbari, Amir; Esmaeilpour, Tahereh; Bahmanpour, Soghra; Golmohammadi, Mohammad Ghasem; Sharififar, Sharareh; Azari, Hassan

    2015-01-01

    Abstract Introduction Neural stem cells (NSCs) reside along the ventricular axis of the mammalian brain. They divide infrequently to maintain themselves and the down‐stream progenitors. Due to the quiescent property of NSCs, attempts to deplete these cells using antimitotic agents such as cytosine b‐Aarabinofuranoside (Ara‐C) have not been successful. We hypothesized that implementing infusion gaps in Ara‐C kill paradigms would recruit the quiescent NSCs and subsequently eliminate them from t...

  1. Vector-borne Infections

    Centers for Disease Control (CDC) Podcasts

    2011-04-18

    This podcast discusses emerging vector-borne pathogens, their role as prominent contributors to emerging infectious diseases, how they're spread, and the ineffectiveness of mosquito control methods.  Created: 4/18/2011 by National Center for Emerging Zoonotic and Infectious Diseases (NCEZID).   Date Released: 4/27/2011.

  2. Vector-borne diseases.

    Science.gov (United States)

    Gubler, D J

    2009-08-01

    Vector-borne diseases have been the scourge of man and animals since the beginning of time. Historically, these are the diseases that caused the great plagues such as the 'Black Death' in Europe in the 14th Century and the epidemics of yellow fever that plagued the development of the New World. Others, such as Nagana, contributed to the lack of development in Africa for many years. At the turn of the 20th Century, vector-borne diseases were among the most serious public and animal health problems in the world. For the most part, these diseases were controlled by the middle of the 20th Century through the application of knowledge about their natural history along with the judicious use of DDT (dichlorodiphenyltrichloroethane) and other residual insecticides to interrupt the transmission cycle between arthropod and vertebrate host. However, this success initiated a period of complacency in the 1960s and 1970s, which resulted in the redirection of resources away from prevention and control of vector-borne diseases. The 1970s was also a time in which there were major changes to public health policy. Global trends, combined with changes in animal husbandry, urbanisation, modern transportation and globalisation, have resulted in a global re-emergence of epidemic vector-borne diseases affecting both humans and animals over the past 30 years. PMID:20128467

  3. Tick-Borne Encephalitis (TBE)

    Science.gov (United States)

    ... Search The CDC Cancel Submit Search The CDC Tick-borne Encephalitis (TBE) Note: Javascript is disabled or ... CDC.gov . Recommend on Facebook Tweet Share Compartir Tick-borne encephalitis, or TBE, is a human viral ...

  4. Where was Joseph Babinski born?

    Directory of Open Access Journals (Sweden)

    H A G Teive

    2011-01-01

    Full Text Available There is controversy in the neurological literature about where Joseph Babinski was born, including a myth propounded by various important authors that he was born in Lima, Peru. However, according to the most consistent biographical data, he was in fact born in Paris, France, and became a medical celebrity there and in Poland as well as around the world.

  5. Born-Infeld Cosmologies

    CERN Document Server

    García-Salcedo, R; Garcia-Salcedo, Ricardo; Breton, Nora

    2000-01-01

    We present a model for an inhomogeneous and anisotropic early universe filled with a nonlinear electromagnetic field of Born-Infeld (BI) type. The effects of the BI field are compared with the linear case (Maxwell). Since the curvature invaria nts are well behaved then we conjecture that our model does not present an initial big bang singularity. The existence of the BI field modifies the curvature invariants at t=0 as well as sets bounds on the amplitude of the conformal metric function

  6. Building a Subduction Zone Observatory

    Science.gov (United States)

    Gomberg, Joan S.; Bodin, Paul; Bourgeois, Jody; Cashman, Susan; Cowan, Darrel; Creager, Kenneth C.; Crowell, Brendan; Duvall, Alison; Frankel, Arthur; Gonzalez, Frank; Houston, Heidi; Johnson, Paul; Kelsey, Harvey; Miller, Una; Roland, Emily C.; Schmidt, David; Staisch, Lydia; Vidale, John; Wilcock, William; Wirth, Erin

    2016-01-01

    Subduction zones contain many of Earth’s most remarkable geologic structures, from the deepest oceanic trenches to glacier-covered mountains and steaming volcanoes. These environments formed through spectacular events: Nature’s largest earthquakes, tsunamis, and volcanic eruptions are born here.

  7. Born In Bradford Mobile Application

    OpenAIRE

    Lee, Stella; Walda, Martin; Vasiliki, Delimpasi

    2015-01-01

    The Born In Bradford mobile application is an Android mobile application and a working prototype that enables interaction with a sample cohort of the Born in Bradford study. It provides an interface and visualization for several surveys participated in by mothers and their children. This data is stored in the Born In Bradford database. A subset of this data is provided for mothers and children. The mobile application provides a way to engage the mothers and promote their consistency in partic...

  8. Parasitic food-borne and water-borne zoonoses.

    Science.gov (United States)

    Macpherson, C N; Gottstein, B; Geerts, S

    2000-04-01

    Estimates suggest that almost half of the population of the world is affected by water-borne and food-borne infections. Parasitic food-borne and water-borne zoonoses contribute to this statistic by inflicting a heavy toll on human health and causing serious direct and indirect losses to the agricultural industry. The inability of non-industrialised countries to keep pace with population growth, migration from rural to urban areas and the demand for clean, safe drinking water and proper sanitation means that water-borne zoonoses will continue to exact an increasing burden of ill health in these countries. The consumption of raw or undercooked meat, crustaceans, and fresh-water fish and vegetables facilitates transmission of large numbers of zoonotic infections. The burgeoning tourist industry, emigration and the importation of food from endemic regions has resulted in increasing diagnosis of these infections in non-endemic countries. The authors examine the epidemiology, medical and veterinary public health importance and recent developments in diagnosis, treatment and control of the most important parasitic food-borne and water-borne infections.

  9. Early Recollections of First-Borns.

    Science.gov (United States)

    Fakouri, M. Ebrahim; Hafner, James L.

    1984-01-01

    Compared the early recollections of 50 first-borns and 98 later-borns. The first-borns mentioned significantly more nonfamily members, illness/injury, hospital/doctor's office. Later-borns mentioned significantly more siblings than did first-borns. Findings were discussed in the context of Adler's personality theory. (JAC)

  10. Born : vastutustundlikud tulevikus edukad / Kerstin Born ; interv. Kristo Kiviorg

    Index Scriptorium Estoniae

    Born, Kerstin

    2007-01-01

    Vastutustundliku ettevõtluse Euroopa organisatsiooni CSR Europe'i juht Kerstin Born vastab küsimustele ettevõtete vastutustundlikkuse kohta ühiskonnas. Vt. samas: Käivitus vastutustundliku ettevõtluse indeks

  11. Born-Infeld cosmology with scalar Born-Infeld matter

    CERN Document Server

    Jana, Soumya

    2016-01-01

    Cosmology in Eddington-inspired Born-Infeld gravity is investigated using a scalar Born-Infeld field (eg. tachyon condensate) as matter. In this way, both in the gravity and matter sectors we have Born-Infeld-like structures characterised by their actions and via two separate constants, $\\kappa$ and $\\alpha_T^2$ respectively. With a particular choice of the form of $\\dot{\\phi}$ (time derivative of the Born-Infeld scalar), analytical cosmological solutions are found. Thereafter, we explore some of the unique features of the corresponding cosmological spacetimes. For $\\kappa>0$, our solution has a de Sitter-like expansion both at early and late times, with an intermediate deceleration sandwiched between the accelerating phases. On the other hand, when $\\kappa0$ solution, are as good as in $\\Lambda$CDM cosmology. However, the $\\kappa<0$ solution has to be discarded due to the occurrence of a bounce at an unacceptably low redshift.

  12. Born Rule and Noncontextual Probability

    CERN Document Server

    Logiurato, Fabrizio

    2012-01-01

    The probabilistic rule that links the formalism of Quantum Mechanics (QM) to the real world was stated by Born in 1926. Since then, there were many attempts to derive the Born postulate as a theorem, Gleason's one being the most prominent. The Gleason derivation, however, is generally considered as rather intricate and its physical meaning, in particular in relation with the noncontextuality of probability (NP), is not quite evident. More recently, we are witnessing a revival of interest on possible demonstrations of the Born rule, like Zurek's and Deutsch's based on the decoherence and on the theory of decisions, respectively. Despite an ongoing debate about the presence of hidden assumptions and circular reasonings, these have the merit of prompting more physically oriented approaches to the problem. Here we suggest a new proof of the Born rule based on the noncontextuality of probability. Within the theorem we also demonstrate the continuity of probability with respect to the amplitudes, which has been sug...

  13. Conditional reduction of adult born doublecortin-positive neurons reversibly impairs selective behaviours

    Directory of Open Access Journals (Sweden)

    Lillian eGarrett

    2015-11-01

    Full Text Available Adult neurogenesis occurs in the adult mammalian subventricular zone (SVZ along the walls of the lateral ventricles and the subgranular zone (SGZ of the hippocampal dentate gyrus. While a burgeoning body of research implicates adult neurogenesis in olfactory bulb (OB - and hippocampal-related behaviors, the precise function continues to elude. To further assess the behavioral importance of adult neurogenesis, we herein generated a novel inducible transgenic mouse model of adult neurogenesis reduction where mice with CreERT2 under doublecortin (DCX promoter control were crossed with mice where diphtheria toxin A (DTA was driven by the Rosa26 promoter. Activation of DTA, through the administration of tamoxifen (TAM, results in a specific reduction of DCX+ immature neurons in both the hippocampal dentate gyrus and OB. We show that the decrease of DCX+ cells causes impaired social discrimination ability in both young adult (from 3 months and middle (from 10 months aged mice. Furthermore, these animals showed an age-independent altered coping behavior in the Forced Swim Test without clear changes in anxiety-related behavior. Notably, these behavior changes were reversible on repopulating the neurogenic zones with DCX+ cells on cessation of the tamoxifen treatment, demonstrating the specificity of this effect. Overall, these results support the notion that adult neurogenesis plays a role in social memory and in stress coping but not necessarily in anxiety-related behavior.

  14. Antimicrobial Impacts of Essential Oils on Food Borne-Pathogens.

    Science.gov (United States)

    Ozogul, Yesim; Kuley, Esmeray; Ucar, Yilmaz; Ozogul, Fatih

    2015-01-01

    The antimicrobial activity of twelve essential oil (pine oil, eucalyptus, thyme, sage tea, lavender, orange, laurel, lemon, myrtle, lemon, rosemary and juniper) was tested by a disc diffusion method against food borne pathogens (Escherichia coli, Salmonella paratyphi A, Klebsiella pneumoniae, Yersinia enterocolitica, Pseudomonas aeruginosa, Aeromonas hydrophila, Campylobacter jejuni, Enterococcus faecalis, Staphylococcus aureus). The major components in essential oils were monoterpenes hydrocarbons, α-pinene, limonene; monoterpene phenol, carvacrol and oxygenated monoterpenes, camphor, 1,8-cineole, eucalyptol, linalool and linalyl acetate. Although the antimicrobial effect of essential oils varied depending on the chemical composition of the essential oils and specific microorganism tested, majority of the oils exhibited antibacterial activity against one or more strains. The essential oil with the lowest inhibition zones was juniper with the values varied from 1.5 to 6 mm. However, the components of essential oil of thyme and pine oil are highly active against food borne pathogen, generating the largest inhibition zones for both gram negative and positive bacteria (5.25-28.25 mm vs. 12.5-30 mm inhibition zones). These results indicate the possible use of the essential oils on food system as antimicrobial agents against food-borne pathogen. The article also offers some promising patents on applications of essential oils on food industry as antimicrobial agent. PMID:26072990

  15. Melanin-concentrating hormone (MCH) immunoreactivity in non-neuronal cells within the raphe nuclei and subventricular region of the brainstem of the cat.

    Science.gov (United States)

    Torterolo, Pablo; Lagos, Patricia; Sampogna, Sharon; Chase, Michael H

    2008-05-19

    Neurons that utilize melanin-concentrating hormone (MCH) as a neuromodulator are localized within the postero-lateral hypothalamus and zona incerta. These neurons project diffusely throughout the central nervous system and have been implicated in critical physiological processes such as energy homeostasis and sleep. In the present report, we examined the distribution of MCH immunoreactivity in the brainstem of the cat. In addition to MCH+ axons, we found MCH-immunoreactive cells that have not been previously described either in the midbrain raphe nuclei or in the periaqueductal and periventricular areas. These MCH+ cells constituted: 1. ependymal cells that lined the fourth ventricle and aqueduct, 2. ependymal cells with long basal processes that projected deeply into the subventricular (subaqueductal) parenchyma, and, 3. cells in subventricular regions and the midbrain raphe nuclei. The MCH+ cells in the midbrain raphe nuclei were closely related to neuronal processes of serotonergic neurons. Utilizing Neu-N and GFAP immunohistochemistry we determined that the preceding MCH+ cells were neither neurons nor astrocytes. However, we found that vimentin, an intermediate-filament protein that is used as a marker for tanycytes, was specifically co-localized with MCH in these cells. We conclude that MCH is present in tanycytes whose processes innervate the midbrain raphe nuclei and adjacent subependymal regions. Because tanycytes are specialized cells that transport substances from the cerebrospinal fluid (CSF) to neural parenchyma, we suggest that MCH is absorbed from the CSF by tanycytes and subsequently liberate to act upon neurons of brainstem nuclei. PMID:18410908

  16. Born-Infeld cosmology with scalar Born-Infeld matter

    Science.gov (United States)

    Jana, Soumya; Kar, Sayan

    2016-09-01

    Cosmology in Eddington-inspired Born-Infeld gravity is investigated using a scalar Born-Infeld field (e.g. tachyon condensate) as matter. In this way, both in the gravity and matter sectors we have Born-Infeld-like structures characterized by their actions and via two separate constants, κ and αT2 , respectively. With a particular choice of the form of ϕ ˙ (the time derivative of the Born-Infeld scalar), analytical cosmological solutions are found. Thereafter, we explore some of the unique features of the corresponding cosmological spacetimes. For κ >0 , our solution has a de Sitter-like expansion both at early and late times, with an intermediate deceleration sandwiched between the accelerating phases. On the other hand, when κ data—a fact we demonstrate explicitly. The estimated properties of the Universe obtained from the fitting of the κ >0 solution are as good as in Λ CDM cosmology. However, the κ <0 solution has to be discarded due to the occurrence of a bounce at an unacceptably low redshift.

  17. Bilateral Transplantation of Allogenic Adult Human Bone Marrow-Derived Mesenchymal Stem Cells into the Subventricular Zone of Parkinson’s Disease: A Pilot Clinical Study

    Directory of Open Access Journals (Sweden)

    N. K. Venkataramana

    2012-01-01

    Full Text Available The progress of PD and its related disorders cannot be prevented with the medications available. In this study, we recruited 8 PD and 4 PD plus patients between 5 to 15 years after diagnosis. All patients received BM-MSCs bilaterally into the SVZ and were followed up for 12 months. PD patients after therapy reported a mean improvement of 17.92% during “on” and 31.21% during “off” period on the UPDRS scoring system. None of the patients increased their medication during the follow-up period. Subjectively, the patients reported clarity in speech, reduction in tremors, rigidity, and freezing attacks. The results correlated with the duration of the disease. Those patients transplanted in the early stages of the disease (less than 5 years showed more improvement and no further disease progression than the later stages (11–15 years. However, the PD plus patients did not show any change in their clinical status after stem cell transplantation. This study demonstrates the safety of adult allogenic human BM-MSCs transplanted into the SVZ of the brain and its efficacy in early-stage PD patients.

  18. The neural elements in the lining of the ventricular-subventricular zone: making an old story new by high-resolution scanning electron microscopy

    Directory of Open Access Journals (Sweden)

    Carlos Alexandre Dos Santos Haemmerle

    2015-10-01

    Full Text Available The classical description of the neural elements that compose the lining of brain ventricles introduces us to the single layer of ependymal cells. However, new findings, especially in the lateral ventricle - the major niche for the generation of new neurons in the adult brain - have provided information about additional cell elements that influence the organization of this part of the ventricular system and produce important contributions to neurogenesis. To complement the cell neurochemistry findings, we present a three-dimensional in situ description that demonstrates the anatomical details of the different types of ciliated cells and the innervation of these elements. After processing adult rat brains for ultrastructural analysis by high-resolution scanning electron microscopy and transmission electron microscopy, we observed a heterogeneous pattern of cilia distribution at the different poles of the lateral ventricle surface. Furthermore, we describe the particular three-dimensional aspects of the ciliated cells of the lateral ventricle, in addition the fiber bundles and varicose axons surrounding these cells. Therefore, we provide a unique ultrastructural description of the three-dimensional in situ organization of the lateral ventricle surface, highlighting its innervation, to corroborate the available neurochemical and functional findings regarding the factors that regulate this neurogenic niche.

  19. GABA(A) Increases Calcium in Subventricular Zone Astrocyte-Like Cells Through L- and T-Type Voltage-Gated Calcium Channels

    DEFF Research Database (Denmark)

    Young, Stephanie Z; Platel, Jean-Claude; Nielsen, Jakob V;

    2010-01-01

    induced Ca(2+) increases in 40-50% of SVZ astrocytes. GABA(A)-induced Ca(2+) increases were prevented with nifedipine and mibefradil, blockers of L- and T-type voltage-gated calcium channels (VGCC). The L-type Ca(2+) channel activator BayK 8644 increased the percentage of GABA(A)-responding astrocyte...

  20. Adult Neurogenesis in the Mammalian Hippocampus: Why the Dentate Gyrus?

    Science.gov (United States)

    Drew, Liam J.; Fusi, Stefano; Hen, René

    2013-01-01

    In the adult mammalian brain, newly generated neurons are continuously incorporated into two networks: interneurons born in the subventricular zone migrate to the olfactory bulb, whereas the dentate gyrus (DG) of the hippocampus integrates locally born principal neurons. That the rest of the mammalian brain loses significant neurogenic capacity…

  1. Born Reciprocity and Cosmic Accelerations

    CERN Document Server

    Bolognesi, S

    2015-01-01

    The trans-Planckian theory is a model that realizes concretely the Born reciprocity idea, which is the postulate of absolute equivalence between coordinate $x$ and momenta $p$. This model is intrinsically global, and thus it is naturally implemented in a cosmological setting. Cosmology and Born reciprocity are made for each other. Inflation provides the essential mechanism to suppress the terms coming from the dual part of the action. The trans-Planckian theory, on the other hand, provides an explanation for the accelerated periods of the universe scale factor, both the inflationary period and the present period dominated by dark energy. All of this is possible just considering a simple model that contains gravity, one gauge field plus one matter field (to be identified with dark matter) together with the reciprocity principle.

  2. Detection of Water Borne Protozoa

    DEFF Research Database (Denmark)

    Al-Sabi, Mohammad Nafi Solaiman; Enemark, Heidi L.; Kurtzhals, J.A.L.

    Protozoa of several species play a key role in water borne outbreaks of diarrhea worldwide. Identification of such protozoa depends mainly on parasite detection. However, water contains several hundreds of thousands of microorganisms belonging to different taxa. The exact identification...... of pathogenic protozoa relies on selective isolation and detection that is conducted by experienced technicians. Advanced techniques such as immuno-fluorescent dyes, polymerase chain reaction, and many other techniques, may be used for species-specific identification of pathogenic protozoa. Each diagnostic...

  3. Brand Building of Born Globals

    OpenAIRE

    Cederäng, Jesper; Norberg, Markus

    2008-01-01

    Abstract The purpose of this thesis was to increase the understanding of two early internationalizing firms (Born Globals) brand building efforts. By performing case studies on these companies we wished to discover similarities and differences in their marketing efforts. The companies that we studied were CTEK Sweden AB, a battery charger manufacturer and POC Sweden AB, who designs advanced protective gear for the alpine ski market. The theoretical framework was divided according to the four ...

  4. Horizon structure and shadow of rotating Einstein-Born-Infeld black holes

    Science.gov (United States)

    Atamurotov, Farruh

    2016-07-01

    We investigate the horizon structure of the rotating Einstein-Born-Infeld solution which goes over to the Einstein-Maxwell's Kerr-Newman solution as the Born-Infeld parameter goes to innity ( ! 1). We nd that for a given , mass M and charge Q, there exist critical spinning parameter aE and rEH, which corresponds to an extremal Einstein-Born-Infeld black hole with degenerate horizons, and aE decreases and rEH increases with increase in the Born-Infeld parameter . While a shadow as an optical appearance due to its strong gravitational eld. We also investigate the shadow cast by the rotating Einstein- Born-Infeld black hole and demonstrate that the null geodesic equations can be integrated that allows us to investigate the shadow cast by a black hole which is found to be a dark zone covered by a circle. Interestingly, the shadows of Einstein-Born-Infeld black hole is slightly smaller than for the Reissner-Nordstrom black hole which are concentric circles, for different values of the Born-Infeld parameter , whose radius decreases with increase in the value of parameter . The shadows for the rotating Einstein-Born-Infeld solution are also included.

  5. Guardians of New-Borns

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    WITH 38 years of history, the Beijing Maternity Hospital gained fame as the birthplace of one-fifth of all Beijingers in the 1960s. Today, some 5,000 babies are born here each year. As Beijing’s oldest hospital specializing in gynaecology and obstetrics treatment and research, the Beijing Maternity Hospital ranks top among all maternity hospitals in China. Chen Wenshan. 52. oversees 272 nurses working at BMH. A vigorous and extremely strict woman. Chen is both respected and feared by the nurses on her staff. As the director of the Nursing

  6. Pulsars are Born as Magnetars

    CERN Document Server

    Heras, Ricardo

    2013-01-01

    This paper suggests the idea that all neutron stars experienced at birth an ultrafast decay of their magnetic fields from their initial values to their current surface values. If the electromagnetic energy radiated during this field decay is converted into kinetic energy of the neutron star via the radiation reaction mechanism then the decay time is of the order of 10^(-4)s provided that the initial magnetic fields lie in the range of 10^(14)-10^(16)G. This means that all neutron stars are born with magnetic fields typical of magnetars. According to this model the neutron stars acquire their observed high space velocities during the birth ultrafast decay of their magnetic fields. The origin of this field decay points to magnetic instabilities occurring at the end of the birth process.

  7. Horizon structure of rotating Einstein-Born-Infeld black holes and shadow

    Energy Technology Data Exchange (ETDEWEB)

    Atamurotov, Farruh [Institute of Nuclear Physics, Tashkent (Uzbekistan); Inha University in Tashkent, Tashkent (Uzbekistan); Ulugh Beg Astronomical Institute, Tashkent (Uzbekistan); National University of Uzbekistan, Tashkent (Uzbekistan); Ghosh, Sushant G. [Jamia Millia Islamia, Centre for Theoretical Physics, New Delhi (India); University of Kwa-Zulu-Natal, Astrophysics and Cosmology Research Unit, School of Mathematical Sciences, Private Bag 54001, Durban (South Africa); Ahmedov, Bobomurat [Institute of Nuclear Physics, Tashkent (Uzbekistan); Ulugh Beg Astronomical Institute, Tashkent (Uzbekistan); National University of Uzbekistan, Tashkent (Uzbekistan)

    2016-05-15

    We investigate the horizon structure of the rotating Einstein-Born-Infeld solution which goes over to the Einstein-Maxwell's Kerr-Newman solution as the Born-Infeld parameter goes to infinity (β → ∞). We find that for a given β, mass M, and charge Q, there exist a critical spinning parameter a{sub E} and r{sub H}{sup E}, which corresponds to an extremal Einstein-Born-Infeld black hole with degenerate horizons, and a{sub E} decreases and r{sub H}{sup E} increases with increase of the Born-Infeld parameter β, while a < a{sub E} describes a non-extremal Einstein-Born-Infeld black hole with outer and inner horizons. Similarly, the effect of β on the infinite redshift surface and in turn on the ergo-region is also included. It is well known that a black hole can cast a shadow as an optical appearance due to its strong gravitational field. We also investigate the shadow cast by the both static and rotating Einstein-Born-Infeld black hole and demonstrate that the null geodesic equations can be integrated, which allows us to investigate the shadow cast by a black hole which is found to be a dark zone covered by a circle. Interestingly, the shadow of an Einstein-Born-Infeld black hole is slightly smaller than for the Reissner-Nordstrom black hole, which consists of concentric circles, for different values of the Born-Infeld parameter β, whose radius decreases with increase of the value of the parameter β. Finally, we have studied observable distortion parameter for shadow of the rotating Einstein-Born-Infeld black hole. (orig.)

  8. Conceptualizing Innovation in Born Global Firms

    DEFF Research Database (Denmark)

    Zijdemans, Erik; Tanev, Stoyan

    2014-01-01

    This research provides insights from recent literature on innovativeness in the environment of born globals. This article will be relevant to researchers interested in born globals and their business environments and, more specifically, the role that innovation plays in their foundation and devel...

  9. Literacy Skills of Children Born Preterm

    Science.gov (United States)

    Holm, Alison; Crosbie, Sharon

    2010-01-01

    Most children born preterm are considered neurologically normal and free of disability. However in follow-up studies at school age, preterm children, born without major impairment, have been shown to have lower cognitive abilities and associated academic, social and behavioural difficulties. This study investigated the literacy, phonological…

  10. PEOPLE BORN IN AUTUMN LIVE LONGER

    Institute of Scientific and Technical Information of China (English)

    张梦华

    2004-01-01

    People born in the autumn live longer an those born in the spring and are less likely to fall chronically ill when they are older,according to an Austrian scientist.Using census data for more than one million people in Austria,Denmark and Australia,scien-

  11. Rescuing the Born Rule for Quantum Cosmology

    CERN Document Server

    Cooperman, Joshua H

    2010-01-01

    Page has recently argued that the Born rule does not suffice for computing all probabilities in quantum cosmology. He further asserts that the Born rule's failure gives rise to the cosmological measure problem. Here I contend that Page's result stems from his use of an overly restrictive definition of the Born rule. In particular, I demonstrate that all of the probabilities he wishes to compute follow from the Born rule when generalized measurements are permitted. I also register two comments on Page's theoretical setting, relating respectively to Hilbert space dimensionality and permutation symmetry. These considerations lead me to conclude that the claimed insufficiency of the Born rule is by no means specific to the cosmological context.

  12. Calculation of distribution of effective reflection area for space-borne laser retro-reflector array

    Institute of Scientific and Technical Information of China (English)

    HU; Jingfu; LI; Xin; YANG; Fumin; CHEN; Wanzhen

    2004-01-01

    The effective area of space-borne laser retro-reflector directly influences the intensity of the return signals for satellite laser ranging. The configuration of the retro-reflector array determines the effective area. The formula for the effective area of the space-borne retro-reflector array with different inclination angles at arbitrary celestial zone was deduced in this paper. As an example, the calculation result about effective area for the retro-reflector array of the Shenzhou-IV orbital module was given.

  13. [Climate- and vector-borne diseases

    DEFF Research Database (Denmark)

    Bygbjerg, I.C.; Schioler, K.L.; Konradsen, F.

    2009-01-01

    The predicted changes in climate have raised concerns that vector-borne diseases may emerge or expand in tempered regions. Malaria, leishmaniasis and tick-borne illnesses are discussed in terms of climate change and their endemic potential, especially in Denmark. While climate may play an important...... role in disease patterns, it is evident that transmission potential is governed by a complex of factors, including socio-economy, health-care capacity and ecology. In Denmark, malaria and leishmaniasis are unlikely to become public health problems, whereas the potential for tick-borne illnesses may...

  14. Potato soil-borne diseases. A review

    OpenAIRE

    Fiers, Marie; Edel-Hermann, Veronique; Chatot, Catherine; Le Hingrat, Yves; ALABOUVETTE, Claude; Steinberg, Christian

    2012-01-01

    Potato crop is the fourth main food crop in the world and it will certainly feed a big part of the global population in the next years. The economical outlets for this crop are great; however, numerous diseases either soil- or air-borne can cause huge losses in the production. Worldwide, about 40 soil-borne diseases affect potato and cause severe damages especially on tubers, the economically most important part of the plant. The occurrence and development of soil-borne diseases depend on ver...

  15. New neurons in the adult brain : The role of sleep and consequences of sleep loss

    NARCIS (Netherlands)

    Meerlo, Peter; Mistiberger, Ralph E.; Jacobs, Barry L.; Heller, H. Craig; McGinty, Dennis; Mistlberger, Ralph E.

    2009-01-01

    Research over the last few decades has firmly established that new neurons are generated in selected areas of the adult mammalian brain, particularly the dentate gyrus of the hippocampal formation and the subventricular zone of the lateral ventricles. The function of adult-born neurons is still a ma

  16. Structure-borne noise at hotels

    Science.gov (United States)

    Wilson, George Paul; Jue, Deborah A.

    2002-11-01

    Hotels present a challenging environment for building designers to provide suitable noise and vibration isolation between very incompatible uses. While many are familiar with ways to reduce traditional sources of airborne noise and vibration, structure-borne noise and vibration are often overlooked, often with costly repercussions. Structure-borne noise can be very difficult to pinpoint, and troubleshooting the sources of the vibration can be a tedious process. Therefore, the best approach is to avoid the problem altogether during design, with attention to the building construction, potential vibration sources, building uses and equipment locations. In this paper, the relationship between structure-borne vibration and noise are reviewed, typical vibration sources discussed (e.g., aerobic rooms, laundry rooms, mechanical equipment/building services, and subway rail transit), and key details and design guidance to minimize structure-borne noise provided.

  17. Tick-Borne Diseases: The Big Two

    Science.gov (United States)

    ... Ticks and Diseases Tick-borne Diseases: The Big Two Past Issues / Spring - Summer 2010 Table of Contents ... muscle pain. The red-spotted rash usually happens 2 to 5 days after the fever begins. Antibiotics ...

  18. Photonic processes in Born-Infeld theory

    Science.gov (United States)

    Dávila, José Manuel; Schubert, Christian; Trejo, María Anabel

    2014-12-01

    We study the processes of photon-photon scattering and photon splitting in a magnetic field in Born-Infeld theory. In both cases we combine the terms from the tree-level Born-Infeld Lagrangian with the usual one-loop QED contributions, where those are approximated by the Euler-Heisenberg Lagrangian, including also the interference terms. For photon-photon scattering we obtain the total cross-section in the low-energy approximation. For photon splitting we compute the total absorption coefficient in the hexagon (weak field) approximation, and also show that, due to the non-birefringence property of Born-Infeld theory, the selection rules found by Adler for the QED case continue to hold in this more general setting. We discuss the bounds on the free parameter of Born-Infeld theory that may be obtained from this type of processes.

  19. Photonic processes in Born-Infeld theory

    CERN Document Server

    Davila, Jose Manuel; Trejo, Maria Anabel

    2013-01-01

    We study the processes of photon-photon scattering and photon splitting in a magnetic field in Born-Infeld theory. In both cases we combine the terms from the tree-level Born-Infeld Lagrangian with the usual one-loop QED contributions, where those are approximated by the Euler-Heisenberg Lagrangian, including also the interference terms. For photon-photon scattering we obtain the total cross section in the low-energy approximation. For photon splitting we compute the total absorption coefficient in the hexagon (weak field) approximation, and also show that, due to the non-birefringence property of Born-Infeld theory, the selection rules found by Adler for the QED case continue to hold in this more general setting. We discuss the bounds on the free parameter of Born-Infeld theory that may be obtained from this type of processes.

  20. Born-Infeld action and Supersymmetry

    CERN Document Server

    Silva, G A

    2000-01-01

    In the thesis we analize different problems related to the supersymmetric extension of the Dirac-Born-Infeld action. In chapter 2 we introduce the DBI action and show how it appears in string theory, we discuss also it's connection with Dp-branes. Chapter 3 is a self contained introduction to supersymmetry, with emphasis on BPS states. In chapter 4 we construct the N=2 supersymmetric extension of the Born-Infeld-Higgs in three space-time dimensions and discuss it's BPS states and Bogomol'nyi bounds. In chapter 5 we construct the N=1 supersymmetric extension of the non-abelian Born-Infeld theory in four space-time dimensions. Chapter 6 deals with the analisis of BPS and non-BPS solutions of the Dirac-Born-Infeld action and their interpretation in superstring theory. Chapter 7 is devoted to the conclusions. Three appendix complete the work.

  1. Skyrmions from a Born-Infeld action

    Science.gov (United States)

    Dion, B.; Marleau, L.; Simon, G.

    1996-02-01

    We consider geometrically motivated Higgs sector solitons based on a general covariant kinetic term proposed originally by Born and Infeld. We introduce this new term by generalizing the Born-Infeld action to a non-Abelian SU(2) gauge theory and by using the hidden gauge symmetry formalism. The static and stability properties of the solitons are then analyzed and compared with Skyrme-like models.

  2. Born-Infeld Gravity in any Dimension

    OpenAIRE

    Nieto, J.A.

    2004-01-01

    We develop a Born-Infeld type theory for gravity in any dimension. We show that in four dimensions our formalism allows a self-dual (or anti-self dual) Born-Infeld gravity description. Moreover, we show that such a self-dual action is reduced to both the Deser-Gibbons and the Jacobson-Smolin-Samuel action of Ashtekar formulation. A supersymmetric generalization of our approach is outlined.

  3. 2D Born-Infeld electrostatic fields

    OpenAIRE

    Ferraro, Rafael

    2003-01-01

    The electrostatic configurations of the Born-Infeld field in the 2-dimensional Euclidean plane are obtained by means of a non-analytical complex mapping which captures the structure of equipotential and field lines. The electrostatic field reaches the Born-Infeld limit value when the field lines become tangent to an epicycloid around the origin. The total energy by unit of length remains finite.

  4. Foreign-born Peers and Academic Performance.

    Science.gov (United States)

    Conger, Dylan

    2015-04-01

    The academic performance of foreign-born youth in the United States is well studied, yet little is known about whether and how foreign-born students influence their classmates. In this article, I develop a set of expectations regarding the potential consequences of immigrant integration across schools, with a distinction between the effects of sharing schools with immigrants who are designated as English language learners (ELL) and those who are not. I then use administrative data on multiple cohorts of Florida public high school students to estimate the effect of immigrant shares on immigrant and native-born students' academic performance. The identification strategy pays careful attention to the selection problem by estimating the effect of foreign-born peers from deviations in the share foreign-born across cohorts of students attending the same school in different years. The assumption underlying this approach is that students choose schools based on the composition of the entire school, not on the composition of each entering cohort. The results of the analysis, which hold under several robustness checks, indicate that foreign-born peers (both those who are ELL and those who are non-ELL) have no effect on their high school classmates' academic performance. PMID:25651879

  5. Urbanization, land tenure security and vector-borne Chagas disease

    Science.gov (United States)

    Levy, Michael Z.; Barbu, Corentin M.; Castillo-Neyra, Ricardo; Quispe-Machaca, Victor R.; Ancca-Juarez, Jenny; Escalante-Mejia, Patricia; Borrini-Mayori, Katty; Niemierko, Malwina; Mabud, Tarub S.; Behrman, Jere R.; Naquira-Velarde, Cesar

    2014-01-01

    Modern cities represent one of the fastest growing ecosystems on the planet. Urbanization occurs in stages; each stage characterized by a distinct habitat that may be more or less susceptible to the establishment of disease vector populations and the transmission of vector-borne pathogens. We performed longitudinal entomological and epidemiological surveys in households along a 1900 × 125 m transect of Arequipa, Peru, a major city of nearly one million inhabitants, in which the transmission of Trypanosoma cruzi, the aetiological agent of Chagas disease, by the insect vector Triatoma infestans, is an ongoing problem. The transect spans a cline of urban development from established communities to land invasions. We find that the vector is tracking the development of the city, and the parasite, in turn, is tracking the dispersal of the vector. New urbanizations are free of vector infestation for decades. T. cruzi transmission is very recent and concentrated in more established communities. The increase in land tenure security during the course of urbanization, if not accompanied by reasonable and enforceable zoning codes, initiates an influx of construction materials, people and animals that creates fertile conditions for epidemics of some vector-borne diseases. PMID:24990681

  6. Assessment of changes of vector borne diseases with wetland characteristics using multivariate analysis.

    Science.gov (United States)

    Sheela, A M; Sarun, S; Justus, J; Vineetha, P; Sheeja, R V

    2015-04-01

    Vector borne diseases are a threat to human health. Little attention has been paid to the prevention of these diseases. We attempted to identify the significant wetland characteristics associated with the spread of chikungunya, dengue fever and malaria in Kerala, a tropical region of South West India using multivariate analyses (hierarchical cluster analysis, factor analysis and multiple regression). High/medium turbid coastal lagoons and inland water-logged wetlands with aquatic vegetation have significant effect on the incidence of chikungunya while dengue influenced by high turbid coastal beaches and malaria by medium turbid coastal beaches. The high turbidity in water is due to the urban waste discharge namely sewage, sullage and garbage from the densely populated cities and towns. The large extent of wetland is low land area favours the occurrence of vector borne diseases. Hence the provision of pollution control measures at source including soil erosion control measures is vital. The identification of vulnerable zones favouring the vector borne diseases will help the authorities to control pollution especially from urban areas and prevent these vector borne diseases. Future research should cover land use cover changes, climatic factors, seasonal variations in weather and pollution factors favouring the occurrence of vector borne diseases. PMID:25412801

  7. Zoning Districts, Zoning, Published in 2002, Freelance.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Zoning Districts dataset, was produced all or in part from Hardcopy Maps information as of 2002. It is described as 'Zoning'. Data by this publisher are often...

  8. Tornado-borne missile speeds. Final report

    International Nuclear Information System (INIS)

    An investigation of the question of tornado-borne missile speeds was carried out, with a view to identify pertinent areas of uncertainty and to estimate credible tornado-borne missile speeds - within the limitations inherent in the present state of the art. The investigation consists of two parts: (1) a study in which a rational model for the missile motion is proposed, and numerical experiments are carried out corresponding to various assumptions on the initial conditions of the missile motion, the structure of the tornado flow, and the aerodynamic properties of the missile; (2) a theoretical and experimental study of tornado-borne missile aerodynamics, conducted by Colorado State Univ. (CSU) to be covered in a separate report by CSU. In the present report, the factors affecting missile motion and their influence upon such motion are examined

  9. Pap Tests and Foreign-Born Women

    Centers for Disease Control (CDC) Podcasts

    2007-11-26

    Foreign-born women living in the U.S. are less likely to have Pap tests to detect cervical cancer than women born in this country. The problem is worse for women from certain countries or regions. Find out why this is a disturbing trend, who these women are and why they are less likely to get a Pap test, and what CDC is doing about it.  Created: 11/26/2007 by National Breast and Cervical Cancer Early Detection Program.   Date Released: 12/7/2007.

  10. Projectile-Borne Video Reconnaissance System

    Institute of Scientific and Technical Information of China (English)

    王海福; 张锋; 李向荣

    2004-01-01

    Aiming at applications as a projectile-borne video reconnaissance system, the overall design and prototype in principle of a mortar video reconnaissance system bomb were developed. Mortar launched test results show that the initial integrated system was capable of transmitting images through tens of kilometers with the image resolution identifying effectively tactical targets such as roads, hills, caverns, trees and rivers. The projectile-borne video reconnaissance system is able to meet the needs of tactical target identification and battle dage assessment for tactical operations. The study will provide significant technological support for further independent development.

  11. Photonic processes in Born-Infeld theory

    OpenAIRE

    Davila, Jose Manuel; Schubert, Christian; Trejo, Maria Anabel

    2013-01-01

    We study the processes of photon-photon scattering and photon splitting in a magnetic field in Born-Infeld theory. In both cases we combine the terms from the tree-level Born-Infeld Lagrangian with the usual one-loop QED contributions, where those are approximated by the Euler-Heisenberg Lagrangian, including also the interference terms. For photon-photon scattering we obtain the total cross section in the low-energy approximation. For photon splitting we compute the total absorption coeffici...

  12. Relativistic bound states at Born level

    CERN Document Server

    Hoyer, Paul

    2012-01-01

    Theoretical and phenomenological studies indicate that the QCD coupling \\alpha_s(Q^2) freezes in the infrared. Hadrons may then be described by a perturbative expansion around "Born" states bound only by a confining potential. A linear potential results from the QCD equations of motion when Gauss' law for A^0 is solved with F_{\\mu\

  13. [Conflicts and vector-borne diseases

    DEFF Research Database (Denmark)

    Bygbjerg, Ib Christian

    2010-01-01

    Based on literature and personal experiences, vector-borne diseases and conflicts are reviewed. Simple rapid diagnostic tests for three important parasitoses are available. Resort is often made to case definitions and to presumptive treatment. Resistance is an emerging problem. Vaccines are still...

  14. The Eco-Epidemiology of Tick-Borne Hemoparasitic Diseases Using Geographic Information Systems

    Directory of Open Access Journals (Sweden)

    Javad Rafinejad

    2013-12-01

    Full Text Available Background: Tick-borne diseases are of the most important diseases in the world including Iran. This survey was conducted to understand the eco-epidemiology of tick-borne hemoparasitic diseases in Qazvin province, Iran, using Geospatial Information System (GIS. Materials and Methods: DNA samples were extracted from livestock blood samples collected from different regions of Qazvin province. 18S rRNA-based PCR targeted Theileria/ Babesia species were done. Initial parameters for mapping the local tick-borne hemoparasitic diseases and raster files were obtained from Iran Meteorological Organization and Iranian Space Agency. Mapping of the parameters in relation to prevalence of these diseases were done. Statistical analysis was used for weighting parameters ranking and predicting spatial distribution in different climatic zones. Results: Vapor pressure, precipitation, and altitude are of several environmental factors correlated with tick abundances. Based on the generated maps and the results of this survey, some predicting results could be used for predicting tick-borne diseases and their control. 9.7% of ruminant blood samples (N=16 were infected with protozoa pathogens from the genera Theileria and all of the specimens were negative regarding to Babesia genera. Conclusion: Results showed that prediction of a very high prevalence of Theileria/ Babesia species and mapping endangered area is possible in different parts of Iran. Based on the environmental conditions, key factors exist for host-seeking and range expansion of ticks.

  15. Differences in the self-reported racism experiences of US-born and foreign-born Black pregnant women

    OpenAIRE

    Dominguez, Tyan Parker; Strong, Emily Ficklin; Krieger, Nancy; Gillman, Matthew W; Rich-Edwards, Janet W

    2009-01-01

    Differential exposure to minority status stressors may help explain differences in United States (US)-born and foreign-born Black women’s birth outcomes. We explored self-reports of racism recorded in a survey of 185 US-born and 114 foreign-born Black pregnant women enrolled in Project Viva, a prospective cohort study of pregnant women in Boston, Massachusetts, USA. Self-reported prevalence of personal racism and group racism was significantly higher among US-born than foreign-born Black preg...

  16. Approximated solutions to Born-Infeld dynamics

    Science.gov (United States)

    Ferraro, Rafael; Nigro, Mauro

    2016-02-01

    The Born-Infeld equation in the plane is usefully captured in complex language. The general exact solution can be written as a combination of holomorphic and anti-holomorphic functions. However, this solution only expresses the potential in an implicit way. We rework the formulation to obtain the complex potential in an explicit way, by means of a perturbative procedure. We take care of the secular behavior common to this kind of approach, by resorting to a symmetry the equation has at the considered order of approximation. We apply the method to build approximated solutions to Born-Infeld electrodynamics. We solve for BI electromagnetic waves traveling in opposite directions. We study the propagation at interfaces, with the aim of searching for effects susceptible to experimental detection. In particular, we show that a reflected wave is produced when a wave is incident on a semi-space containing a magnetostatic field.

  17. Attitude determination for balloon-borne experiments

    CERN Document Server

    Gandilo, N N; Amiri, M; Angile, F E; Benton, S J; Bock, J J; Bond, J R; Bryan, S A; Chiang, H C; Contaldi, C R; Crill, B P; Devlin, M J; Dober, B; Dore, O P; Farhang, M; Filippini, J P; Fissel, L M; Fraisse, A A; Fukui, Y; Galitzki, N; Gambrel, A E; Golwala, S; Gudmundsson, J E; Halpern, M; Hasselfield, M; Hilton, G C; Holmes, W A; Hristov, V V; Irwin, K D; Jones, W C; Kermish, Z D; Klein, J; Korotkov, A L; Kuo, C L; MacTavish, C J; Mason, P V; Matthews, T G; Megerian, K G; Moncelsi, L; Morford, T A; Mroczkowski, T K; Nagy, J M; Netterfield, C B; Novak, G; Nutter, D; O'Brient, R; Pascale, E; Poidevin, F; Rahlin, A S; Reintsema, C D; Ruhl, J E; Runyan, M C; Savini, G; Scott, D; Shariff, J A; Soler, J D; Thomas, N E; Trangsrud, A; Truch, M D; Tucker, C E; Tucker, G S; Tucker, R S; Turner, A D; Ward-Thompson, D; Weber, A C; Wiebe, D V; Young, E Y

    2014-01-01

    An attitude determination system for balloon-borne experiments is presented. The system provides pointing information in azimuth and elevation for instruments flying on stratospheric balloons over Antarctica. In-flight attitude is given by the real-time combination of readings from star cameras, a magnetometer, sun sensors, GPS, gyroscopes, tilt sensors and an elevation encoder. Post-flight attitude reconstruction is determined from star camera solutions, interpolated by the gyroscopes using an extended Kalman Filter. The multi-sensor system was employed by the Balloon-borne Large Aperture Submillimeter Telescope for Polarimetry (BLASTPol), an experiment that measures polarized thermal emission from interstellar dust clouds. A similar system was designed for the upcoming flight of SPIDER, a Cosmic Microwave Background polarization experiment. The pointing requirements for these experiments are discussed, as well as the challenges in designing attitude reconstruction systems for high altitude balloon flights. ...

  18. Geometrical dynamics of Born-Infeld objects

    Energy Technology Data Exchange (ETDEWEB)

    Cordero, Ruben [Departamento de Fisica, Escuela Superior de Fisica y Matematicas del I.P.N., Unidad Adolfo Lopez Mateos, Edificio 9, 07738 Mexico, D.F. (Mexico); Molgado, Alberto [Facultad de Ciencias, Universidad de Colima, Bernal DIaz del Castillo 340, Col. Villas San Sebastian, Colima (Mexico); Rojas, Efrain [Facultad de Fisica e Inteligencia Artificial, Universidad Veracruzana, 91000 Xalapa, Veracruz (Mexico)

    2007-03-21

    We present a geometrically inspired study of the dynamics of Dp-branes. We focus on the usual non-polynomial Dirac-Born-Infeld action for the worldvolume swept out by the brane in its evolution in general background spacetimes. We emphasize the form of the resulting equations of motion which are quite simple and resemble Newton's second law, complemented with a conservation law for a worldvolume bicurrent. We take a closer look at the classical Hamiltonian analysis which is supported by the ADM framework of general relativity. The constraints and their algebra are identified as well as the geometrical role they play in phase space. In order to illustrate our results, we review the dynamics of a D1-brane immersed in a AdS{sub 3} x S{sup 3} background spacetime. We exhibit the mechanical properties of Born-Infeld objects paving the way to a consistent quantum formulation.

  19. TIMWE : Born Global Firm : case study

    OpenAIRE

    Marques, Frederico José Castro Reis

    2013-01-01

    TIMWE is the Portuguese based company chosen to illustrate and serve as background to support the creation of a teaching case in Strategy, exploring the internationalization of a real company and the challenges undertaken by the process of being a born global firm, followed by a Teaching Note that can be used as a tool to help solving the case. TIMWE is a Portuguese owned company, founded in 2002, that offers mobile monetization solutions and services (entertainment, marketing and money) t...

  20. Quantum heat transfer: A Born Oppenheimer method

    OpenAIRE

    Wu, Lian-Ao; Segal, Dvira

    2010-01-01

    We develop a Born-Oppenheimer type formalism for the description of quantum thermal transport along hybrid nanoscale objects. Our formalism is suitable for treating heat transfer in the off-resonant regime, where e.g., the relevant vibrational modes of the interlocated molecule are high relative to typical bath frequencies, and at low temperatures when tunneling effects dominate. A general expression for the thermal energy current is accomplished, in the form of a generalized Landauer formula...

  1. Suppression of soil-borne plant pathogens

    OpenAIRE

    Agtmaal, van, E.L.

    2015-01-01

    Soil borne plant pathogens considerably reduce crop yields worldwide and are difficult to control due to their ”masked” occurrence  in the heterogeneous soil environment. This hampers the efficacy of chemical - and microbiological control agents.   Outbreaks of crop diseases are not only dependent on the presence of pathogen propagules in the soil, but are also influenced by soil-related properties like physico-chemical characteristics, microbial activity and commun...

  2. Teenagers born at extremely low birth weight

    OpenAIRE

    Whitfield, Michael F.; Grunau, Ruth E

    2006-01-01

    Adolescence constitutes a major transition for extremely low birth weight (ELBW) teenagers. Recent studies of ELBW teenagers born in the 1980s have provided information about the growth and developmental characteristics of these individuals in adolescence and in early adulthood. ELBW teenagers are shorter and lighter than their full-term peers, and have a smaller head circumference. Cognitive and academic vulnerabilities documented during the school years, particularly difficulties with nonve...

  3. Gravity a la Born-Infeld

    CERN Document Server

    Wohlfarth, M N R

    2004-01-01

    A simple technique for the construction of gravity theories in Born-Infeld style is presented, and the properties of some of these novel theories are investigated. They regularize the positive energy Schwarzschild singularity, and a large class of models allows for the cancellation of ghosts. The possible correspondence to low energy string theory is discussed. By including curvature corrections to all orders in alpha', the new theories nicely illustrate a mechanism that string theory might use to regularize gravitational singularities.

  4. Climate change and mosquito-borne disease.

    OpenAIRE

    Reiter, P.

    2001-01-01

    Global atmospheric temperatures are presently in a warming phase that began 250--300 years ago. Speculations on the potential impact of continued warming on human health often focus on mosquito-borne diseases. Elementary models suggest that higher global temperatures will enhance their transmission rates and extend their geographic ranges. However, the histories of three such diseases--malaria, yellow fever, and dengue--reveal that climate has rarely been the principal determinant of their pr...

  5. Dynamics of Born-Infeld membranes

    Energy Technology Data Exchange (ETDEWEB)

    Cordero, R [Departamento de Fisica, Escuela Superior de Fisica y Matematicas del I.P.N., Unidad Adolfo Lopez Mateos, Edificio 9, 07738 Mexico, D.F. (Mexico); Molgado, A [Facultad de Ciencias, Universidad de Colima, Bernal DIaz del Castillo 340, Col. Villas San Sebastian, Colima (Mexico); Rojas, E [Facultad de Fisica e Inteligencia Artificial, Universidad Veracruzana, 91000 Xalapa, Veracruz (Mexico)

    2007-11-15

    We present a geometrical inspired study of the dynamics of Dp-branes. We focus on the usual nonpolynomial Dirac-Born-Infeld action for the worldvolume swept out by the brane in its evolution in general background spacetimes. We emphasize the form of the resulting equations of motion which are quite simple and resemble Newton's second law, complemented with a conservation law for a worldvolume bicurrent.

  6. Operatorial quantization of Born-Infeld Skyrmions

    CERN Document Server

    Neto, J A; Oliveira, W; Neto, Jorge Ananias; Oliveira, Emanuel R. de; Oliveira, Wilson

    1999-01-01

    The SU(2) collective coordinates quantization of the Born-Infeld Skyrmions Lagrangean is performed. The obtainment of the classical Hamiltonian from this special Lagrangean is made by using an approximate way: it is derived from the expansion of this non-polynomial Lagrangean up to second-order variable in the collective coordinates, using for this some causality arguments. Because this system presents constraints, we use the Dirac Hamiltonian method and the Faddeev-Jackiw Lagrangean approach to quantize this model.

  7. Non-linear 3-D Born shear waveform tomography in Southeast Asia

    Science.gov (United States)

    Panning, Mark P.; Cao, Aimin; Kim, Ahyi; Romanowicz, Barbara A.

    2012-07-01

    Southeast (SE) Asia is a tectonically complex region surrounded by many active source regions, thus an ideal test bed for developments in seismic tomography. Much recent development in tomography has been based on 3-D sensitivity kernels based on the first-order Born approximation, but there are potential problems with this approach when applied to waveform data. In this study, we develop a radially anisotropic model of SE Asia using long-period multimode waveforms. We use a theoretical 'cascade' approach, starting with a large-scale Eurasian model developed using 2-D Non-linear Asymptotic Coupling Theory (NACT) sensitivity kernels, and then using a modified Born approximation (nBorn), shown to be more accurate at modelling waveforms, to invert a subset of the data for structure in a subregion (longitude 75°-150° and latitude 0°-45°). In this subregion, the model is parametrized at a spherical spline level 6 (˜200 km). The data set is also inverted using NACT and purely linear 3-D Born kernels. All three final models fit the data well, with just under 80 per cent variance reduction as calculated using the corresponding theory, but the nBorn model shows more detailed structure than the NACT model throughout and has much better resolution at depths greater than 250 km. Based on variance analysis, the purely linear Born kernels do not provide as good a fit to the data due to deviations from linearity for the waveform data set used in this modelling. The nBorn isotropic model shows a stronger fast velocity anomaly beneath the Tibetan Plateau in the depth range of 150-250 km, which disappears at greater depth, consistent with other studies. It also indicates moderate thinning of the high-velocity plate in the middle of Tibet, consistent with a model where Tibet is underplated by Indian lithosphere from the south and Eurasian lithosphere from the north, in contrast to a model with continuous underplating by Indian lithosphere across the entire plateau. The nBorn

  8. Outbreaks of food-borne and waterborne viral gastroenteritis.

    OpenAIRE

    Hedberg, C W; Osterholm, M T

    1993-01-01

    Norwalk virus infection is the epidemiologic prototype for outbreaks of food-borne and waterborne gastroenteritis. Around the world, Norwalk virus and Norwalk-like viruses appear to be major causes of food-borne and waterborne illness. Assessment of the overall significance of viral agents to the epidemiology of food-borne and waterborne illness is hampered by the lack of surveillance throughout much of the world. In areas where food-borne and waterborne illness surveillance is conducted, out...

  9. Investigation of Anti-bacterial Activity against Food-borne Pathogens among Korean Domestic Algae

    Directory of Open Access Journals (Sweden)

    Ki-hyo Jang

    2015-03-01

    Full Text Available The aim of this study is to explore algal species with anti-bacterial activity against six food-borne pathogens. Among 51 marine algae, Laurencia okamurae Yamada and Dictyopteris undulata Holmes was elucidated to have a potent anti-bacterial activity against food-borne pathogens. Laurencia okamurae Yamada showed the clear zone around agar well on B. cereus, S. aureusand L. monocytogenes-spreading agar plate. Dictyopteris undulata Holmes had the anti-bacterial activity against S. chorelaesuis, B. cereus, S. aureus and L. monocytogenes on bacterial spreading agar plates. Antibacterial activity of L. okamurae Yamada and D. undulata Holmes had specifically susceptibility for B. cereus, S. aureus and L. monocytogenes and were superior to streptomycin, the authentic antibiotics. It is anticipated that new food preservatives can be explored and developed on the basis of this study.

  10. Root Apex Transition Zone as Oscillatory Zone

    Directory of Open Access Journals (Sweden)

    Frantisek eBaluska

    2013-10-01

    Full Text Available Root apex of higher plants shows very high sensitivity to environmental stimuli. The root cap acts as the most prominent plant sensory organ; sensing diverse physical parameters such as gravity, light, humidity, oxygen and critical inorganic nutrients. However, the motoric responses to these stimuli are accomplished in the elongation region. This spatial discrepancy was solved when we have discovered and characterized the transition zone which is interpolated between the apical meristem and the subapical elongation zone. Cells of this zone are very active in the cytoskeletal rearrangements, endocytosis and endocytic vesicle recycling, as well as in electric activities. Here we discuss the oscillatory nature of the transition zone which, together with several other features of this zone, suggest that it acts as some kind of command centre. In accordance with the early proposal of Charles and Francis Darwins, cells of this root zone receive sensory information from the root cap and instruct the motoric responses of cells in the elongation zone.

  11. Promotion of Cortical Neurogenesis from the Neural Stem Cells in the Adult Mouse Subcallosal Zone.

    Science.gov (United States)

    Kim, Joo Yeon; Choi, Kyuhyun; Shaker, Mohammed R; Lee, Ju-Hyun; Lee, Boram; Lee, Eunsoo; Park, Jae-Yong; Lim, Mi-Sun; Park, Chang-Hwan; Shin, Ki Soon; Kim, Hyun; Geum, Dongho; Sun, Woong

    2016-04-01

    Neurogenesis occurs spontaneously in the subventricular zone (SVZ) of the lateral ventricle in adult rodent brain, but it has long been debated whether there is sufficient adult neurogenesis in human SVZ. Subcallosal zone (SCZ), a posterior continuum of SVZ closely associated with posterior regions of cortical white matter, has also been reported to contain adult neural stem cells (aNSCs) in both rodents and humans. However, little is known whether SCZ-derived aNSC (SCZ-aNSCs) can produce cortical neurons following brain injury. We found that SCZ-aNSCs exhibited limited neuronal differentiation potential in culture and after transplantation in mice. Neuroblasts derived from SCZ initially migrated toward injured cortex regions following brain injury, but later exhibited apoptosis. Overexpression of anti-apoptotic bcl-xL in the SCZ by retroviral infection rescued neuroblasts from cell death in the injured cortex, but neuronal maturation was still limited, resulting in atrophy. In combination with Bcl-xL, infusion of brain-derived neurotropic factor rescued atrophy, and importantly, a subset of such SCZ-aNSCs differentiated and attained morphological and physiological characteristics of mature, excitatory neurons. These results suggest that the combination of anti-apoptotic and neurotrophic factors might enable the use of aNSCs derived from the SCZ in cortical neurogenesis for neural replacement therapy. Stem Cells 2016;34:888-901. PMID:26701067

  12. Modulation of adult-born neurons in the inflamed hippocampus

    Directory of Open Access Journals (Sweden)

    Karim eBelarbi

    2013-09-01

    Full Text Available Throughout life new neurons are continuously added to the hippocampal circuitry involved with spatial learning and memory. These new cells originate from neural precursors in the subgranular zone of the dentate gyrus, migrate into the granule cell layer and integrate into neural networks encoding spatial and contextual information. This process can be influenced by several environmental and endogenous factors and is modified in different animal models of neurological disorders. Neuroinflammation, as defined by the presence of activated microglia, is a common key factor to the progression of neurological disorders. Analysis of the literature shows that microglial activation impacts not only the production, but also the migration and the recruitment of new neurons. The impact of microglia on adult-born neurons appears much more multifaceted than ever envisioned before, combining both supportive and detrimental effects that are dependent upon the activation phenotype and the factors being released. The development of strategies aimed to change microglia toward states that promote functional neurogenesis could therefore offer novel therapeutic opportunities against neurological disorders associated with cognitive deficits and neuroinflammation. The present review summarizes the current knowledge on how production, distribution and recruitment of new neurons into behaviorally relevant neural networks are modified in the inflamed hippocampus.

  13. Anisotropy in Born-Infeld brane cosmology

    OpenAIRE

    Haghani, Z.; Sepangi, H. R.; shahidi, S.

    2011-01-01

    The accelerated expansion of the universe together with its present day isotropy has posed an interesting challenge to the numerous model theories presented over the years to describe them. In this paper, we address the above questions in the context of a brane-world model where the universe is filled with a Born-Infeld matter. We show that in such a model, the universe evolves from a highly anisotropic state to its present isotropic form which has entered an accelerated expanding phase.

  14. Born with Protection against Whooping Cough

    Centers for Disease Control (CDC) Podcasts

    2015-01-22

    This podcast provides information about whooping cough, a disease that can be deadly for babies, and CDC’s recommendation that all women receive the Tdap vaccine during the third trimester of every pregnancy so their babies can be born with protection from this serious disease.  Created: 1/22/2015 by National Center for Immunization and Respiratory Diseases (NCIRD), Division of Bacterial Diseases (DBD), Meningitis and Vaccine Preventable Diseases Branch (MVPDB).   Date Released: 1/22/2015.

  15. Cosmic String Global Superconducting Dirac Born Infeld

    Science.gov (United States)

    Ikrima, Ika; Ramadhan, Handhika S.; Mart, Terry

    2016-08-01

    Superconducting cosmic string possibly plays an important role in the formation of the universe structure. The physics of this phenomenon has been explored by studying the field theory in the string interior. Numerical solutions of superconducting strings with all relevant fields are presented in this paper. The field is constructed from a generalization of the usual field theory of superconducting global string, but the kinetic term consists of the Dirac Born Infeld (DBI). Some changes in the characteristic of the superconducting string DBI from the usual superconducting string case have been observed. The observation includes physical mechanism of all related fields.

  16. Gravity a la Born-Infeld

    Energy Technology Data Exchange (ETDEWEB)

    Wohlfarth, Mattias N R [Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom)

    2004-04-21

    A simple technique for the construction of gravity theories in Born-Infeld style is presented, and the properties of some of these novel theories are investigated. They regularize the positive energy Schwarzschild singularity, and a large class of models allows for the cancellation of ghosts. The possible correspondence with low-energy string theory is discussed. By including curvature corrections to all orders in {alpha}', the new theories nicely illustrate a mechanism that string theory might use to regularize gravitational singularities.

  17. Born expansions for charged particle scattering

    International Nuclear Information System (INIS)

    High-order terms in Born expansions of scattering amplitudes in powers of charge are frequently divergent when long-range Coulomb interactions are present asymptotically. Expansions which are free from these logarithmic divergences have been constructed recently. This paper illustrates these expansions with the simplest example, namely the non-relativistic Rutherford scattering of two charged particles. This approach represents an adequate framework for the calculation of transition amplitudes and a comprehensive starting point for the development of consistent perturbation approximations in multi-channel descriptions of strongly interacting atomic systems

  18. Paced-mating increases the number of adult new born cells in the internal cellular (granular layer of the accessory olfactory bulb.

    Directory of Open Access Journals (Sweden)

    Rebeca Corona

    Full Text Available The continuous production and addition of new neurons during life in the olfactory bulb is well accepted and has been extensively studied in rodents. This process could allow the animals to adapt to a changing environment. Olfactory neurogenesis begins in the subventricular zone where stem cells proliferate and give rise to young undifferentiated neuroblasts that migrate along the rostral migratory stream to the olfactory bulb (OB. Olfaction is crucial for the expression of sexual behavior in rodents. In female rats, the ability to control the rate of sexual interactions (pacing has important physiological and behavioral consequences. In the present experiment we evaluated if pacing behavior modifies the rate of new cells that reach the main and accessory olfactory bulb. The BrdU marker was injected before and after different behavioral tests which included: females placed in a mating cage (control, females allowed to pace the sexual interaction, females that mated but were not able to control the rate of the sexual interaction and females exposed to a sexually active male. Subjects were sacrificed fifteen days after the behavioral test. We observed a significant increase in the density of BrdU positive cells in the internal cellular layer of the accessory olfactory bulb when females paced the sexual interaction in comparison to the other 3 groups. No differences in the cell density in the main olfactory bulb were found. These results suggest that pacing behavior promotes an increase in density of the new cells in the accessory olfactory bulb.

  19. Second order Born calculation for charge transfer

    International Nuclear Information System (INIS)

    Charge transfer cross sections, from the ground state of the target to the ground state of the projectile, have been computed in a second order Born approximation for protons incident upon hydrogen at energies of 1, 10, and 50 MeV. The exact second order matrix element is evaluated numerically, and the results are compared to a standard peaking approximation (SP), as well as to a new peaking approximation (LP) developed herein. At 50 MeV two distinct second order effects are evident in the differential cross section. For very small (center of mass) scattering angles (THETA approx. = .0320) the second order cross section is smaller than the first order cross section, while at larger angles (THETA approx. = .0540) a second Born peak occurs. This peak can be kinematically associated with a classical two step process which gives rise to the well known dominating v-11 asymptotic velocity dependence of the total cross section. The reduction of the differential cross section at smaller angles serves to decrease the total cross section, as is predicted by the asymptotic expression. At 10 MeV second order effects become less important, and at 1 MeV the kinematic peak has all but disappeared, while the second order cross section has here become larger than the first order cross section. At intermediate energies experimental results indicate that the first order cross section used here is itself too large

  20. Attitude determination for balloon-borne experiments

    Science.gov (United States)

    Gandilo, N. N.; Ade, P. A. R.; Amiri, M.; Angilè, F. E.; Benton, S. J.; Bock, J. J.; Bond, J. R.; Bryan, S. A.; Chiang, H. C.; Contaldi, C. R.; Crill, B. P.; Devlin, M. J.; Dober, B.; Doré, O. P.; Farhang, M.; Filippini, J. P.; Fissel, L. M.; Fraisse, A. A.; Fukui, Y.; Galitzki, N.; Gambrel, A. E.; Golwala, S.; Gudmundsson, J. E.; Halpern, M.; Hasselfield, M.; Hilton, G. C.; Holmes, W. A.; Hristov, V. V.; Irwin, K. D.; Jones, W. C.; Kermish, Z. D.; Klein, J.; Korotkov, A. L.; Kuo, C. L.; MacTavish, C. J.; Mason, P. V.; Matthews, T. G.; Megerian, K. G.; Moncelsi, L.; Morford, T. A.; Mroczkowski, T. K.; Nagy, J. M.; Netterfield, C. B.; Novak, G.; Nutter, D.; O'Brient, R.; Pascale, E.; Poidevin, F.; Rahlin, A. S.; Reintsema, C. D.; Ruhl, J. E.; Runyan, M. C.; Savini, G.; Scott, D.; Shariff, J. A.; Soler, J. D.; Thomas, N. E.; Trangsrud, A.; Truch, M. D.; Tucker, C. E.; Tucker, G. S.; Tucker, R. S.; Turner, A. D.; Ward-Thompson, D.; Weber, A. C.; Wiebe, D. V.; Young, E. Y.

    2014-07-01

    An attitude determination system for balloon-borne experiments is presented. The system provides pointing information in azimuth and elevation for instruments flying on stratospheric balloons over Antarctica. In-flight attitude is given by the real-time combination of readings from star cameras, a magnetometer, sun sensors, GPS, gyroscopes, tilt sensors and an elevation encoder. Post-flight attitude reconstruction is determined from star camera solutions, interpolated by the gyroscopes using an extended Kalman Filter. The multi-sensor system was employed by the Balloon-borne Large Aperture Submillimeter Telescope for Polarimetry (BLASTPol), an experiment that measures polarized thermal emission from interstellar dust clouds. A similar system was designed for the upcoming flight of Spider, a Cosmic Microwave Background polarization experiment. The pointing requirements for these experiments are discussed, as well as the challenges in designing attitude reconstruction systems for high altitude balloon flights. In the 2010 and 2012 BLASTPol flights from McMurdo Station, Antarctica, the system demonstrated an accuracy of < 5' rms in-flight, and < 5" rms post-flight.

  1. Neurodevelopmental outcomes of infants born prematurely.

    Science.gov (United States)

    Aylward, Glen P

    2014-01-01

    Long-term follow-up of infants born prematurely is necessary to determine neurodevelopmental outcomes, particularly with the expansion of interest from major disabilities to high prevalence/low severity dysfunctions. Models of pathogenesis include changes due to developmental disruptions and to injury, the magnitude and type of change influenced by the infant's age, and central nervous system recovery and reorganization. Alterations in neurogenesis, migration, myelination, cell death, and synaptogenesis occur even in the absence of insult. Despite increased knowledge regarding these processes, the functional significance of brain abnormalities is unclear. Because of methodologic problems in follow-up studies, it is difficult to characterize outcome definitively. Nonetheless, an acceptable degree of agreement across studies is found with regard to specific neurodevelopmental outcomes: motor/neurologic function, visuomotor integrative skills, IQ, academic achievement, language, executive function, and attention-deficit hyperactivity disorder/behavioral issues. In general, children born prematurely have more problems in these areas than do their normal birth weight counterparts. Suggestions for improved analyses and clarification of outcomes include use of cluster analysis, structural equation modeling, growth curve analysis, developmental epidemiologic approaches, and better control of background variables using risk indexes and factor scores. Better assessment techniques measuring functions documented to be at higher risk of problems are discussed. PMID:25007063

  2. Extended Born-Infeld Dynamics and Cosmology

    CERN Document Server

    Novello, M; Werneck, L S; Romero, C A

    2005-01-01

    We introduce an extension of the Born-Infeld action for a scalar field and show that it can act as unifying-dark-matter, providing an explanation for both structure formation and the accelerated expansion of the universe. We investigate the cosmological dynamics of this theory in a particular case, referred as the "Milne-Born-Infeld" (MBI) Lagrangian. We show that this model, whose equation of state has effectively a single free parameter, is consistent with recent type Ia supernovae data, providing a fit as good as for the $\\Lambda$CDM model with the same number of degrees of freedom. Furthermore, this parameter is tightly constrained by current data, making the model easily testable with other observables. Contrary to previous candidates for unifying-dark-matter, the sound velocity of the MBI model is vanishing both close to the dark matter state as well as near the cosmological constant state. This could avoid the problems on the matter power spectrum that were present in previous adiabatic dark-matter/dar...

  3. CMB-lensing beyond the Born approximation

    Science.gov (United States)

    Marozzi, Giovanni; Fanizza, Giuseppe; Di Dio, Enea; Durrer, Ruth

    2016-09-01

    We investigate the weak lensing corrections to the cosmic microwave background temperature anisotropies considering effects beyond the Born approximation. To this aim, we use the small deflection angle approximation, to connect the lensed and unlensed power spectra, via expressions for the deflection angles up to third order in the gravitational potential. While the small deflection angle approximation has the drawback to be reliable only for multipoles l lesssim 2500, it allows us to consistently take into account the non-Gaussian nature of cosmological perturbation theory beyond the linear level. The contribution to the lensed temperature power spectrum coming from the non-Gaussian nature of the deflection angle at higher order is a new effect which has not been taken into account in the literature so far. It turns out to be the leading contribution among the post-Born lensing corrections. On the other hand, the effect is smaller than corrections coming from non-linearities in the matter power spectrum, and its imprint on CMB lensing is too small to be seen in present experiments.

  4. Biosensors: tool for food borne pathogen detection

    Directory of Open Access Journals (Sweden)

    Heena Sharma

    2013-12-01

    Full Text Available A paramount and alluring sphere of research, now-a-days, is food analysis, because of the breakneck augmentation of food enterprise and highly hightened maneuverability of today's populations. The management of food quality is very indispensable both for consumer safeguard as well as the food corporations. The biosensors' application in the field of food analysis is quite propitious for the revealing of food borne pathogens. Biosensor, an analytical device, transforms a biological response into an electrical signal. Bioreceptors and transducers are the two main components of a biosensor. Bioreceptor or biorecognition element is the one which leads to the recognition of target analyte and a transducer, for the conversion of recognized event into a measurable electrical signal. The development of biosensors improved the sensitivity and selectivity of detection techniques for food borne pathogens and is rapid, reliable, effective and highly suitable when used in in situ analysis. Since the security in the food supply becomes crucial because of increased perception among consumers and vying nature of food industries, the necessity for expeditious, low volume and sensitive biosensor devices has productively increased. Nevertheless, till date, a very few biosensor systems are available commercially such as Biacore, SpreetaTM, Reichert SR 7000, Analyte 2000, RAPTOR etc. Since, there is ever growing concern regarding safe food and water supply, it is very obvious that the demand for rapid detecting biosensors will also be increasing at par.

  5. The Born rule fails in cosmology

    International Nuclear Information System (INIS)

    The Born rule may be stated mathematically as the rule that probabilities in quantum theory are expectation values of a complete orthogonal set of projection operators. This rule works for single laboratory settings in which the observer can distinguish all the different possible outcomes corresponding to the projection operators. However, theories of inflation suggest that the universe may be so large that any laboratory, no matter how precisely it is defined by its internal state, may exist in a large number of very distantly separated copies throughout the vast universe. In this case, no observer within the universe can distinguish all possible outcomes for all copies of the laboratory. Then normalized probabilities for the local outcomes that can be locally distinguished cannot be given by the expectation values of any projection operators. Thus the Born rule fails and must be replaced by another rule for observational probabilities in cosmology. The freedom of what this new rule is to be is the measure problem in cosmology. A particular volume-averaged form is proposed

  6. CMB-lensing beyond the Born approximation

    CERN Document Server

    Marozzi, Giovanni; Di Dio, Enea; Durrer, Ruth

    2016-01-01

    We investigate the weak lensing corrections to the cosmic microwave background temperature anisotropies considering effects beyond the Born approximation. To this aim, we use the small deflection angle approximation, to connect the lensed and unlensed power spectra, via expressions for the deflection angles up to third order in the gravitational potential. While the small deflection angle approximation has the drawback to be reliable only for multipoles $\\ell\\lesssim 2500$, it allows us to consistently take into account the non-Gaussian nature of cosmological perturbation theory beyond the linear level. The contribution to the lensed temperature power spectrum coming from the non-Gaussian nature of the deflection angle at higher order is a new effect which has not been taken into account in the literature so far. It turns out to be the leading contribution among the post-Born lensing corrections. On the other hand, the effect is smaller than corrections coming from non-linearities in the matter power spectrum...

  7. On Multifield Born and Born-Infeld Theories and their non-Abelian Generalizations

    CERN Document Server

    Cerchiai, B L

    2016-01-01

    Starting from a recently proposed linear formulation in terms of auxiliary fields, we study $n$-field generalizations of Born and Born-Infeld theories. In this description the Lagrangian is quadratic in the vector field strengths and the symmetry properties (including the characteristic self-duality) of the corresponding non-linear theory are manifest as on-shell duality symmetries and depend on the choice of the (homogeneous) manifold spanned by the auxiliary scalar fields and the symplectic frame. By suitably choosing these defining properties of the quadratic Lagrangian, we are able to reproduce some known multi-field Born-Infeld theories and to derive new non-linear models, such as the $n$-field Born theory. We also discuss non-Abelian generalizations of these theories obtained by choosing the vector fields in the adjoint representation of an off-shell compact global symmetry group $K$ and replacing them by non-Abelian, $K$-covariant field strengths, thus promoting $K$ to a gauge group.

  8. Health Beliefs of College Students Born in the United States, China, and India

    Science.gov (United States)

    Rothstein, William G.; Rajapaksa, Sushama

    2003-01-01

    The authors surveyed 243 urban public university students who were born in the United States, China, and India to compare the health beliefs of the China-born, India-born, and US-born students. Although the China- and India-born students shared beliefs in many preventive and therapeutic practices of Western medicine with the US-born students, they…

  9. ANTIBACTERIAL ACTIVITY OF SIMAROUBA GLAUCA LEAF EXTRACTS AGAINST FOOD BORNE SPOILAGE AND PATHOGENIC MICROORGANISMS

    Directory of Open Access Journals (Sweden)

    B. L. Jangale et al.

    2012-02-01

    Full Text Available Crude ethanol and methanol extracts from dried and fresh leaves of Simarouba glauca were tested for their inhibitory activity against two food borne pathogenic microorganisms (Staphylococcus aeureus and Escherichia coli and two food spoilage microorganism (Bacillus subtilis and Pseudomonas aeurogenosa. Screening for antimicrobial activity using well diffusion assay showed the inhibition against entire tested microorganisms. On the other hand the maximum zone of inhibition was recorded of fresh leaves methanol extract (FLM about 11 mm against Escherichia coli and the lowest zone of inhibition was recorded of fresh leaves methanol extract (FLM about 2 mm against Bacillus subtilis. Minimum inhibitory concentrations (MIC’s of extracts were determined using agar dilution method on the same test microorganisms. Fresh leaves methanol (FLM extract gave MIC value ranging from 160 to 10,240 parts per million (ppm. Result showed that the Bacillus subtilis was the most sensitive microorganism.

  10. Blood Pressure in Young Adults Born at Very Low Birth Weight: Adults Born Preterm International Collaboration.

    Science.gov (United States)

    Hovi, Petteri; Vohr, Betty; Ment, Laura R; Doyle, Lex W; McGarvey, Lorcan; Morrison, Katherine M; Evensen, Kari Anne I; van der Pal, Sylvia; Grunau, Ruth E; Brubakk, Ann-Mari; Andersson, Sture; Saigal, Saroj; Kajantie, Eero

    2016-10-01

    Adults born preterm at very low birth weight (VLBW; adults are at risk or whether higher blood pressure could be attributed to some of the specific conditions underlying or accompanying preterm birth. To identify possible risk or protective factors, we combined individual-level data from 9 cohorts that measured blood pressure in young adults born at VLBW or with a more stringent birth weight criterion. In the absence of major heterogeneity, we performed linear regression analysis in our pooled sample of 1571 adults born at VLBW and 777 controls. Adults born at VLBW had 3.4 mm Hg (95% confidence interval, 2.2-4.6) higher systolic and 2.1 mm Hg (95% confidence interval, 1.3-3.0) higher diastolic pressure, with adjustment for age, sex, and cohort. The difference in systolic pressure was present in men (1.8 mm Hg; 95% confidence interval, 0.1-3.5) but was stronger in women (4.7 mm Hg; 95% confidence interval, 3.2-6.3). Among the VLBW group, blood pressure was unrelated to gestational age, maternal smoking, multiple pregnancy, retinopathy of prematurity, or bronchopulmonary dysplasia. Blood pressure was higher than that of controls among VLBW adults unexposed to maternal preeclampsia. Among those exposed, it was even higher, especially if born appropriate for gestational age. In conclusion, although female sex and maternal preeclampsia are additional risk factors, the risk of higher blood pressure is not limited to any etiologic subgroup of VLBW adults, arguing for vigilance in early detection of high blood pressure in all these individuals. PMID:27572149

  11. Generalized Fibonacci zone plates

    CERN Document Server

    Ke, Jie; Zhu, Jianqiang

    2015-01-01

    We propose a family of zone plates which are produced by the generalized Fibonacci sequences and their axial focusing properties are analyzed in detail. Compared with traditional Fresnel zone plates, the generalized Fibonacci zone plates present two axial foci with equal intensity. Besides, we propose an approach to adjust the axial locations of the two foci by means of different optical path difference, and further give the deterministic ratio of the two focal distances which attributes to their own generalized Fibonacci sequences. The generalized Fibonacci zone plates may allow for new applications in micro and nanophotonics.

  12. Shanghai's Development Zones

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Since the early 1980s,development zones began appearing in China.Their Success largely stems from the preferential policies they offer and the safe investment environment they work hard to create.As zones have personalities themselves,it is essential to look beyond the pamphlets and published information and get down to the nittygritty.Shanghai has more State designated Economic and Technology Development Zones than any other city in China.In the following article,we have chosen development zones located around Shanghai and conducted a comparison.

  13. Balloon-borne gamma-ray polarimetry

    CERN Document Server

    Pearce, Mark

    2011-01-01

    The physical processes postulated to explain the high-energy emission mechanisms of compact astrophysical sources often yield polarised soft gamma rays (X-rays). PoGOLite is a balloon-borne polarimeter operating in the 25-80 keV energy band. The polarisation of incident photons is reconstructed using Compton scattering and photoelectric absorption in an array of phoswich detector cells comprising plastic and BGO scintillators, surrounded by a BGO side anticoincidence shield. The polarimeter is aligned to observation targets using a custom attitude control system. The maiden balloon flight is scheduled for summer 2011 from the Esrange Space Centre with the Crab and Cygnus X-1 as the primary observational targets.

  14. Canine vector-borne diseases in Brazil

    Directory of Open Access Journals (Sweden)

    Dantas-Torres Filipe

    2008-08-01

    Full Text Available Abstract Canine vector-borne diseases (CVBDs are highly prevalent in Brazil and represent a challenge to veterinarians and public health workers, since some diseases are of great zoonotic potential. Dogs are affected by many protozoa (e.g., Babesia vogeli, Leishmania infantum, and Trypanosoma cruzi, bacteria (e.g., Anaplasma platys and Ehrlichia canis, and helminths (e.g., Dirofilaria immitis and Dipylidium caninum that are transmitted by a diverse range of arthropod vectors, including ticks, fleas, lice, triatomines, mosquitoes, tabanids, and phlebotomine sand flies. This article focuses on several aspects (etiology, transmission, distribution, prevalence, risk factors, diagnosis, control, prevention, and public health significance of CVBDs in Brazil and discusses research gaps to be addressed in future studies.

  15. Risk based surveillance for vector borne diseases

    DEFF Research Database (Denmark)

    Bødker, Rene

    in Northern Europe. This model approach may be used as a basis for risk based surveillance. In risk based surveillance limited resources for surveillance are targeted at geographical areas most at risk and only when the risk is high. This makes risk based surveillance a cost effective alternative...... to the present surveillance strategies based on random samples. We still don’t understand the mechanisms underlying the recent outbreaks of bluetongue, Schmallenberg, Usutu virus, tick borne encephalitis or dirofilarial worms in the Baltic See Region. It is therefore not possible to use mathematical models...... sample to a diagnostic laboratory. Risk based surveillance models may reduce this delay. An important feature of risk based surveillance models is their ability to continuously communicate the level of risk to veterinarians and hence increase awareness when risk is high. This is essential for submission...

  16. Human sparganosis, a neglected food borne zoonosis.

    Science.gov (United States)

    Liu, Quan; Li, Ming-Wei; Wang, Ze-Dong; Zhao, Guang-Hui; Zhu, Xing-Quan

    2015-10-01

    Human sparganosis is a food borne zoonosis caused by the plerocercoid larvae (spargana) of various diphyllobothroid tapeworms of the genus Spirometra. Human infections are acquired by ingesting the raw or undercooked meat of snakes or frogs, drinking untreated water, or using raw flesh in traditional poultices. More than 1600 cases of sparganosis have been documented worldwide, mostly in east and southeast Asia. Sporadic cases have been reported in South America, Europe, and Africa, and several cases have been described in travellers returning from endemic regions. Epidemiological data suggest that the increased effect of sparganosis on human health is because of greater consumption of raw meat of freshwater frogs and snakes. This Review provides information about the Spirometra parasites and their lifecycles, summarises clinical features, diagnosis, and treatment of human sparganosis, and describes geographical distribution and infection characteristics of Spirometra parasites in host animals. PMID:26364132

  17. Born-Jordan quantization theory and applications

    CERN Document Server

    de Gosson, Maurice A

    2016-01-01

    This book presents a comprehensive mathematical study of the operators behind the Born–Jordan quantization scheme. The Schrödinger and Heisenberg pictures of quantum mechanics are equivalent only if the Born–Jordan scheme is used. Thus, Born–Jordan quantization provides the only physically consistent quantization scheme, as opposed to the Weyl quantization commonly used by physicists. In this book we develop Born–Jordan quantization from an operator-theoretical point of view, and analyze in depth the conceptual differences between the two schemes. We discuss various physically motivated approaches, in particular the Feynman-integral point of view. One important and intriguing feature of Born-Jordan quantization is that it is not one-to-one: there are infinitely many classical observables whose quantization is zero.

  18. ZoneLib

    DEFF Research Database (Denmark)

    Jessen, Jan Jacob; Schiøler, Henrik

    2006-01-01

    We present a dynamic model for climate in a livestock building divided into a number of zones, and a corresponding modular Simulink library (ZoneLib). While most literature in this area consider air flow as a control parameter we show how to model climate dynamics using actual control signals for...

  19. [Autoradiographic investigations on postnatal proliferative activity of the telencephalic and diencephalic matrix-zones in the axolotl (Ambystoma mexicanum), with special references to the olfactory organ (author's transl)].

    Science.gov (United States)

    Richter, W; Kranz, D

    1981-01-01

    The localization and proliferative activity of the matrix-zones has been investigated in the telencephalon and in the diencephalon of 21 axolotls (Ambystoma mexicanum) by means of autoradiographs, after injection of tritiated thymidine at different stages of the postnatal life. There are no previous detailed autoradiographical reports on postnatal brain development in the axolotl. Matrix-zones (i.e. ventricular and subventricular zone) exist in the dorsal part and in the ventral part of the telencephalon, we have found these also in the diencephalon in the wall of the preoptic recessus and ventrally of the habenula. The quantitative part of this study indicates high values of the labeling-index in the early postnatal stages. Then, the labeling-index decreases, but also in 3 years old specimens labeled cells were observed in the matrix-zones of the telencephalon; therefore a few of proliferative capacity remains in the central nervous system of adult axolotls. Labeled cells were also found in the olfactory organ of early postnatal and adult axolotls; these are neuroblasts which have relevance for the regeneration of the forebrain.

  20. Quality of Cancer Care Among Foreign-Born and US-Born Patients With Lung or Colorectal Cancer

    DEFF Research Database (Denmark)

    Nielsen, Signe Smith; He, Yulei; Ayanian, John Z.;

    2010-01-01

      BACKGROUND: Disparities in care have been documented for foreign-born cancer patients in the United States. However, few data are available regarding patients with lung and colorectal cancer. In the current study, the authors assessed whether patient-reported quality and receipt of recommended ....... Better coordination of care and communication regarding cancer treatments and expanded use of interpreters may lessen these disparities.......  BACKGROUND: Disparities in care have been documented for foreign-born cancer patients in the United States. However, few data are available regarding patients with lung and colorectal cancer. In the current study, the authors assessed whether patient-reported quality and receipt of recommended...... care differed between US-born and foreign-born cancer patients. METHODS: The authors collected surveys and medical records for a population-based cohort including white, Hispanic, and Asian adults (2205 US-born and 890 foreign-born individuals) with lung or colorectal cancer diagnosed in California...

  1. Prevalence of Hepatitis B Surface Antigen in US-Born and Foreign-Born Asian/Pacific Islander College Students

    Science.gov (United States)

    Quang, Yen N.; Vu, Joanne; Yuk, Jihey; Li, Chin-Shang; Chen, Moon; Bowlus, Christopher L.

    2010-01-01

    The prevalence of chronic hepatitis B (HBV) among college-age US-born Asian and Pacific Islanders (A/PI) is not well known. Objectives: To compare the prevalence of hepatitis B surface antigen (HBsAg) seropositivity in US-born to A/PI-born students at a public university. Participants: Undergraduate who self-identified themselves as A/PI. Results:…

  2. Born Too Soon: Accelerating actions for prevention and care of 15 million newborns born too soon

    OpenAIRE

    Lawn, JE; Kinney, MV; Belizan, JM; Mason, E.; McDougall, L; Larson, J; Lackritz, E; Friberg, IK; Howson, CP; the Born Too Soon Preterm Birth Action Group (see acknowledgemen

    2013-01-01

    DECLARATION This article is part of a supplement jointly funded by Save the Children's Saving Newborn Lives programme through a grant from The Bill & Melinda Gates Foundation and March of Dimes Foundation and published in collaboration with the Partnership for Maternal, Newborn and Child Health and the World Health Organization (WHO). The original article was published in PDF format in the WHO Report "Born Too Soon: the global action report on preterm birth" (ISBN 978 92 4 150343 30), which i...

  3. Equine tick-borne infections in the Netherlands

    NARCIS (Netherlands)

    Butler, C.M.

    2012-01-01

    This thesis focuses on the emergence and establishment of equine tick-borne infections in the Netherlands, with particular attention to their diagnosis, clinical relevance and treatment. Four tick-borne agents (Borrelia burgdorferi, Theileria equi, Babesia caballi and Anaplasma phagocytophilum) appe

  4. Perinatal outcomes in 375 children born after oocyte donation

    DEFF Research Database (Denmark)

    Malchau, Sara S; Loft, Anne; Larsen, Elisabeth C;

    2013-01-01

    To describe perinatal outcomes in children born after oocyte donation (OD) compared with in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), and spontaneous conception (SC).......To describe perinatal outcomes in children born after oocyte donation (OD) compared with in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), and spontaneous conception (SC)....

  5. Type specimens of Pectinidae (Bivalvia) described by Ignaz von Born

    NARCIS (Netherlands)

    Dijkstra, H.H.

    2009-01-01

    Born described in two publications (1778, 1780) the molluscs in the collection of Empress Maria Theresa (1717-1780), now in the Natural History Museum at Vienna. In this paper the Pectinidae type material is described. Ten new species were introduced of which Argopecten nucleus (Born, 1778) and Minn

  6. Exact second Born electron capture for p+He

    International Nuclear Information System (INIS)

    Formulation and exact numerical calculation of differential and total 1s-1s electron-capture cross sections with the use of the second Born approximation with the free-wave Green's function are presented. At energies above 15 MeV there appears in the differential cross section a peak characteristic of a second Born or two-step process. For total cross sections, our calculations show that below 7 MeV the second-order cross section is larger than the first-order cross section, indicating a breakdown of second-order Born approximation with the free-wave Green's function. Results using the peaking approximation of Drisko converge to our exact second Born results only at energies well above 30 MeV. According to our exact second-Born calculations, observation of the angular distribution above 15 MeV should reveal structure related to at least one two-step mechanism for electron capture

  7. Vector-borne diseases in Haiti: a review.

    Science.gov (United States)

    Ben-Chetrit, Eli; Schwartz, Eli

    2015-01-01

    Haiti lies on the western third of the island of Hispaniola in the Caribbean, and is one of the poorest nations in the Western hemisphere. Haiti attracts a lot of medical attention and support due to severe natural disasters followed by disastrous health consequences. Vector-borne infections are still prevalent there with some unique aspects comparing it to Latin American countries and other Caribbean islands. Although vector-borne viral diseases such as dengue and recently chikungunya can be found in many of the Caribbean islands, including Haiti, there is an apparent distinction of the vector-borne parasitic diseases. Contrary to neighboring Carribbean islands, Haiti is highly endemic for malaria, lymphatic filariasis and mansonellosis. Affected by repeat natural disasters, poverty and lack of adequate infrastructure, control of transmission within Haiti and prevention of dissemination of vector-borne pathogens to other regions is challenging. In this review we summarize some aspects concerning diseases caused by vector-borne pathogens in Haiti.

  8. BLM Solar Energy Zones

    Data.gov (United States)

    Bureau of Land Management, Department of the Interior — Priority development areas for utility-scale solar energy facilities as identified in the Solar PEIS Record of Decision. An additional Solar Energy Zone identified...

  9. Phase zone photon sieve

    Institute of Scientific and Technical Information of China (English)

    Jia Jia; Xie Chang-Qing

    2009-01-01

    A novel diffractive optical element, named phase zone photon sieve (PZPS), is presented. There are three kinds of phase plates in PZPSs: PZPS1, PZPS2, and PZPS3. Each of the PZPSs has its own structure and is made on quartz substrate by etching. The three PZPSs have stronger diffraction peak intensity than a photon sieve (PS) when the margin pinhole and zone line width are kept the same. The PZPS3 can produce a smaller central diffractive spot than the ordinary PS with the same number of zones on the Fresnel zone plate. We have given the design method for and the simulation of PZPS and PS. PZPS has potential applications in optical maskless lithography.

  10. Born Pupils? Natural Pedagogy and Cultural Pedagogy.

    Science.gov (United States)

    Heyes, Cecilia

    2016-03-01

    The theory of natural pedagogy is an important focus of research on the evolution and development of cultural learning. It proposes that we are born pupils; that human children genetically inherit a package of psychological adaptations that make them receptive to teaching. In this article, I first examine the components of the package-eye contact, contingencies, infant-directed speech, gaze cuing, and rational imitation-asking in each case whether current evidence indicates that the component is a reliable feature of infant behavior and a genetic adaptation for teaching. I then discuss three fundamental insights embodied in the theory: Imitation is not enough for cumulative cultural inheritance, the extra comes from blind trust, and tweaking is a powerful source of cognitive change. Combining the results of the empirical review with these insights, I argue that human receptivity to teaching is founded on nonspecific genetic adaptations for social bonding and social learning and acquires its species- and functionally specific features through the operation of domain-general processes of learning in sociocultural contexts. We engage, not in natural pedagogy, but in cultural pedagogy. PMID:26993279

  11. Paratransgenic Control of Vector Borne Diseases

    Directory of Open Access Journals (Sweden)

    Ivy Hurwitz, Annabeth Fieck, Amber Read, Heidi Hillesland, Nichole Klein, Angray Kang, Ravi Durvasula

    2011-01-01

    Full Text Available Conventional methodologies to control vector borne diseases with chemical pesticides are often associated with environmental toxicity, adverse effects on human health and the emergence of insect resistance. In the paratransgenic strategy, symbiotic or commensal microbes of host insects are transformed to express gene products that interfere with pathogen transmission. These genetically altered microbes are re-introduced back to the insect where expression of the engineered molecules decreases the host's ability to transmit the pathogen. We have successfully utilized this strategy to reduce carriage rates of Trypanosoma cruzi, the causative agent of Chagas disease, in the triatomine bug, Rhodnius prolixus, and are currently developing this methodology to control the transmission of Leishmania donovani by the sand fly Phlebotomus argentipes. Several effector molecules, including antimicrobial peptides and highly specific single chain antibodies, are currently being explored for their anti-parasite activities in these two systems. In preparation for eventual field use, we are actively engaged in risk assessment studies addressing the issue of horizontal gene transfer from the modified bacteria to environmental microbes.

  12. The neonate was born with holoprosencephaly

    Directory of Open Access Journals (Sweden)

    reza saeidi

    2014-12-01

    Full Text Available holoprosencephaly is a rare congenital brain malformation resulting from failure of diverticulation and cleavage of primitive prosencephalon which occurs at 4 - 8th week of gestation and is usually associated with multiple midline facial anomalies. it is the most common forebrain developmental anomaly in humans with prevalence of 1/16,000 in live borns, an incidence as high as 1:250 in conceptuses, and a worldwide distribution6. The etiology of HPE is very heterogeneous. First, this pathology can be caused by environmental or metabolic factors. The only formally recognized environmental factors are insulin-dependent diabetes mellitus (1% risk of HPE and maternal alcoholism with a risk that cumulates with smoking . Clinical expression is variable, extending in unbroken sequence from a small brain with a single cerebral ventricle and cyclopia to clinically unaffected carriers in familial holoprosencephaly. Here. we report a boy 39 weeks neonatal case of holoprosencephaly with Antenatal ultrasonographic diagnosis, with microcephaly, hypotelorism, flat nose, a single nostril, a midline cleft lip and palate microcephaly.

  13. BAT-BORNE RABIES IN LATIN AMERICA

    Directory of Open Access Journals (Sweden)

    Luis E. Escobar

    2015-02-01

    Full Text Available The situation of rabies in America is complex: rabies in dogs has decreased dramatically, but bats are increasingly recognized as natural reservoirs of other rabies variants. Here, bat species known to be rabies-positive with different antigenic variants, are summarized in relation to bat conservation status across Latin America. Rabies virus is widespread in Latin American bat species, 22.5%75 of bat species have been confirmed as rabies-positive. Most bat species found rabies positive are classified by the International Union for Conservation of Nature as “Least Concern”. According to diet type, insectivorous bats had the most species known as rabies reservoirs, while in proportion hematophagous bats were the most important. Research at coarse spatial scales must strive to understand rabies ecology; basic information on distribution and population dynamics of many Latin American and Caribbean bat species is needed; and detailed information on effects of landscape change in driving bat-borne rabies outbreaks remains unassessed. Finally, integrated approaches including public health, ecology, and conservation biology are needed to understand and prevent emergent diseases in bats.

  14. Blood-Borne Infections in Tattooed People

    Directory of Open Access Journals (Sweden)

    Hashemi-Shahri

    2016-04-01

    Full Text Available Background Tattoos are associated with blood-borne infections that result from viruses such as the hepatitis B virus (HBV, the hepatitis C virus (HCV, and the human immunodeficiency virus (HIV. This association is equally evident among people without major risk factors and among those with major risk factors like injected drug users (IDUs. Objectives In this study we evaluated all tattooed patients admitted to our hospital (the Boo-Ali hospital in southeastern Iran between February 2006 to January 2015. Patients and Methods The patients enrolled in our study were admitted to infectious disease wards for different illnesses (e. g., Pneumonia, Sepsis, Tuberculosis, etc..We only studied the patients who agreed to be included in our study. When we found at least one tattooed area, regardless of its size, we took a blood sample and tested it for the presence of HIV, HBV, and HCV. Results Among the 63 patients with tattoos (21% female, 79% male, age range:16 to 79-years-old, four patients (6.3% tested positive for HBsAg and PCR-HBV, seven patients (11% tested positive for HCV, and five (7.9% tested positive for HIV. The last group consisted in IDUs and all five had several tattooed areas on their bodies. Conclusions Upon our results, tattooed people even with a small size of tattoo on the body are more at risk for HCV, HBV, and HIV infection.

  15. : Seizure onset zone imaging

    OpenAIRE

    David, Olivier; Blauwblomme, Thomas; Job, Anne-Sophie; Chabardès, Stéphan; Hoffmann, Dominique,; Minotti, Lorella; Kahane, Philippe

    2011-01-01

    International audience Stereo-electroencephalography is used to localize the seizure onset zone and connected neuronal networks in surgical candidates suffering from intractable focal epilepsy. The concept of an epileptogenicity index has been proposed recently to represent the likelihood of various regions being part of the seizure onset zone. It quantifies low-voltage fast activity, the electrophysiological signature of seizure onset usually assessed visually by neurologists. Here, we re...

  16. SIGNR1-Negative Red Pulp Macrophages Protect against Acute Streptococcal Sepsis after Leishmania donovani-Induced Loss of Marginal Zone Macrophages

    NARCIS (Netherlands)

    Kirby, A.C.; Beattie, L.; Maroof, A.; Rooijen, van N.; Kaye, P.M.

    2009-01-01

    Marginal zone macrophages in the murine spleen play an important role in the capture of blood-borne pathogens and are viewed as an essential component of host defense against the development of pneumococcal sepsis. However, we and others have previously described the loss of marginal zone macrophage

  17. Young Adult Outcomes of Children Born to Teen Mothers: Effects of Being Born during Their Teen or Later Years

    Science.gov (United States)

    Lipman, Ellen L.; Georgiades, Katholiki; Boyle, Michael H.

    2011-01-01

    Objective: Children of teen mothers exhibit adverse outcomes through adolescence. It is unclear whether these adverse outcomes extend to adulthood and apply to all of her children, or only those born when she was a teen. We examine the associations between young adult functioning and being born to a teen mother aged less than or equal to 20 years…

  18. The Lived Experiences of Canadian-Born and Foreign-Born Chinese Canadian Post-Secondary Students in Northern Ontario

    Science.gov (United States)

    Wang, Fei

    2016-01-01

    This phenomenological study provided an in-depth description of the internal meaning of the lived experiences of Canadian-born and foreign-born Chinese students in Canada and uncovered the differences in their social experiences. The study used semi-structured interviews to allow the participants to express their views on their lives in Northern…

  19. Genetic diversity of Mycobacterium tuberculosis isolates from foreign-born and Japan-born residents in Tokyo.

    Science.gov (United States)

    Kato-Miyazawa, M; Miyoshi-Akiyama, T; Kanno, Y; Takasaki, J; Kirikae, T; Kobayashi, N

    2015-03-01

    Sequences of the full genomes of 259 clinical isolates of Mycobacterium tuberculosis, obtained from foreign-born and Japan-born patients in Tokyo, Japan, were determined, and a phylogenetic tree constructed by concatenated single-nucleotide polymorphism (SNP) sequences. The 259 isolates were clustered into four clades: Lineage 2 (East Asian or "Beijing" genotype; n = 182, 70.3%), Lineage 4 (Euro-American, n = 46, 17.8%), Lineage 1 (Indo-Oceanic, n = 23, 8.9%), and Lineage 3 (East African-Indian, n = 8, 3.1%). Of the 259, 36 (13.9%) were resistant to at least one drug. There was no multi-drug-resistant isolate. Drug resistance was greater for the strains in Lineage 2 than the non-Lineage 2. The proportion of Lineage 2 isolates was significantly smaller in foreign-born (n = 43/91, 47.3%) than in Japan-born (n = 139/168, 82.7%) patients, whereas the proportion of Lineage 1 isolates was significantly larger in foreign-born (n = 19/91, 20.9%) than in Japan-born (n = 4/168, 2.4%) patients. We also found eight SNPs specific to the typical Beijing sub-genotype in Lineage 2, including 4 non-synonymous SNPs. Of the 259 isolates, 244 had strain-specific SNP(s) and small (1-30-bp) insertions and deletions (indels). The numbers of strain-specific SNPs and indels per isolate were significantly larger from foreign-born (median 89, range 0-520) than from Japan-born (median 23, range 0-415) (p 3.66E-15) patients. These results suggested that M. tuberculosis isolates from foreign-born patients had more genetic diversity than those from Japan-born patients.

  20. New neurons in the adult brain: The role of sleep and consequences of sleep loss

    OpenAIRE

    Meerlo, Peter; Mistlberger, Ralph E.; Jacobs, Barry L.; Heller, H Craig; McGinty, Dennis

    2008-01-01

    Research over the last few decades has firmly established that new neurons are generated in selected areas of the adult mammalian brain, particularly the dentate gyrus of the hippocampal formation and the subventricular zone of the lateral ventricles. The function of adult-born neurons is still a matter of debate. In the case of the hippocampus, integration of new cells in to the existing neuronal circuitry may be involved in memory processes and the regulation of emotionality. In recent year...

  1. Fat-borne volatiles and sheepmeat odour.

    Science.gov (United States)

    Young, O A; Berdagué, J L; Viallon, C; Rousset-Akrim, S; Theriez, M

    1997-02-01

    The effects of lamb age and diet on volatiles from fat are described. Rendered fat from ram lambs raised on ewe's milk then a corn-based diet was compared with that from lambs raised on milk and a pasture of grass/clover, six treatments in all. An additional treatment comprised very old ewes maintained on pasture. Helium-borne volatiles of rendered fat were resolved on a DB5 gas chromatographic column and the mass spectra obtained. Long chain alka(e)nes like neophytadiene were dominant in pasture treatments especially where the lamb growth rate was slow. Branch chain fatty acids (4-methyloctanoic, 4-methylnonanoic and an unidentified acid) were also highest in these treatments. Longer chain aldehydes like 2-undecenal were good indicators of a grain diet. Hexanal, commonly associated with rancid odours, was unaffected by treatment. The diketone 2,3-octanedione was an excellent indicator of a pasture diet, as was 3-methylindole (skatole). Phenols showed complex relationships to treatments, but were generally more common in pasture treatments. Benzenethiol (thiophenol) was unaffected by treatment. Inspection of principal component analysis plots identified 10 volatile compounds as contenders for the cause of sheepmeat odour; branch chain fatty acids were confirmed as the leading chemical class. There were indications that puberty or age caused an increase in the odorous 4-methylnonanoic acid. Animal odour-the odour of confined livestock-was clearly causally linked to 3-methylindole, a rumen breakdown product of tryptophan. 3-Methylindole was also responsible for rancid odour, rather than hexanal and its analogues. A hypothesis is advanced that links 2,3-octanedione formation to the enzyme lipoxygenase and linolenic acid, both abundant in green leafy tissue. Overall, the data confirm that sheepmeat odour/flavour is specifically linked to the branch chain fatty acids, and is probably exacerbated by pasture-derived 3-methylindole and alkyl phenols. PMID:22061302

  2. Flux compactifications in Einstein-Born-Infeld theories

    CERN Document Server

    Ramadhan, Handhika S; Iqbal, Muhammad

    2015-01-01

    We investigate the flux compactification mechanism in simple toy models of Einstein-Born-Infeld theories. These are the direct generalizations of the Einstein-Maxwell flux compactifications that recently gained fame as a toy model for tunneling in the landscape. Our investigation reveals that the Born-Infeld form does not significantly modify the qualitative result of the Einstein-Maxwell theory. for the case of Einstein-Higgs theory, however, we found that the effect of Born-Infeld nonlinearity is to render all q>1 extradimensional compactification unstable against semiclassical tunneling to nothing.

  3. Cognitive ability in adolescents born small for gestational age

    DEFF Research Database (Denmark)

    Jensen, Rikke Beck; Juul, Anders; Larsen, Torben;

    2015-01-01

    BACKGROUND: Small size at birth may be associated with impaired cognitive ability later in life. The aim of this study was to examine the effect of being born small for gestational age (SGA), with or without intrauterine growth restriction (IUGR) on cognitive ability in late adolescence. STUDY...... DESIGN: A follow-up study of a former cohort included 123 participants (52 males); 47 born SGA and 76 born appropriate for gestational age (AGA). Fetal growth velocity (FGV) was determined by serial ultrasound measurements during the third trimester. A control group matched for age and birthplace...

  4. Born-Infeld electrostatics in the complex plane

    CERN Document Server

    Ferraro, Rafael

    2010-01-01

    The complex method to obtain 2-dimensional Born-Infeld electrostatic solutions is presented in a renewed form. The solutions are generated by a holomorphic seed that makes contact with the Coulombian complex potential. The procedure is exemplified by solving the Born-Infeld multipolar configurations. Besides, it is shown that the attractive force between two equal but opposite charges is lower than its Coulombian partner; it decreases up to vanish when the charges approach each other below a distance ruled by the Born-Infeld constant.

  5. Nonlinear Electrodynamics with Singularities (Modernized Born-Infeld Electrodynamics)

    OpenAIRE

    Chernitskii, Alexander A.

    1997-01-01

    Born-Infeld nonlinear electrodynamics are considered. Main attention is given to existence of singular point at static field configuration that M.Born and L.Infeld are considered as a model of electron. It is shown that such singularities are forbidden within the framework of the Born-Infeld model. It is proposed a modernized action that make possible an existence of the singularities. It is obtained main relations in view of the singularities. In initial approximation this model gives the us...

  6. First-born siblings show better second language skills than later born siblings

    Directory of Open Access Journals (Sweden)

    Karin eKeller

    2015-06-01

    Full Text Available We examined the extent to which three sibling structure variables number of siblings, birth order and presence of an older sibling at school age are linked to the second language skills of bilingual children. The research questions were tested using an ethnically heterogeneous sample of 1209 bilingual children with German as a second language. Controlling for children’s age, sex, nationality, number of children’s books at home, family language and parental German language skills, hierarchical regression analyses showed an inverse relationship between the number of siblings and second language skills: The more siblings a child had, the lower was his/her second language proficiency. This relationship was mediated by attendance in early education institutions. Moreover, first-born siblings showed better second language skills than later born siblings.The current study revealed that the resource dilution model, i.e., the decrease in resources for every additional sibling, holds for second language acquisition. Moreover, the results indicate that bilingual children from families with several children benefit from access to early education institutions.

  7. First-born siblings show better second language skills than later born siblings.

    Science.gov (United States)

    Keller, Karin; Troesch, Larissa M; Grob, Alexander

    2015-01-01

    We examined the extent to which three sibling structure variables number of siblings, birth order, and presence of an older sibling at school age are linked to the second language skills of bilingual children. The research questions were tested using an ethnically heterogeneous sample of 1209 bilingual children with German as a second language. Controlling for children's age, sex, nationality, number of children's books at home, family language and parental German language skills, hierarchical regression analyses showed an inverse relationship between the number of siblings and second language skills: the more siblings a child had, the lower was his/her second language proficiency. This relationship was mediated by attendance in early education institutions. Moreover, first-born siblings showed better second language skills than later born siblings. The current study revealed that the resource dilution model, i.e., the decrease in resources for every additional sibling, holds for second language acquisition. Moreover, the results indicate that bilingual children from families with several children benefit from access to early education institutions. PMID:26089806

  8. First-born siblings show better second language skills than later born siblings.

    Science.gov (United States)

    Keller, Karin; Troesch, Larissa M; Grob, Alexander

    2015-01-01

    We examined the extent to which three sibling structure variables number of siblings, birth order, and presence of an older sibling at school age are linked to the second language skills of bilingual children. The research questions were tested using an ethnically heterogeneous sample of 1209 bilingual children with German as a second language. Controlling for children's age, sex, nationality, number of children's books at home, family language and parental German language skills, hierarchical regression analyses showed an inverse relationship between the number of siblings and second language skills: the more siblings a child had, the lower was his/her second language proficiency. This relationship was mediated by attendance in early education institutions. Moreover, first-born siblings showed better second language skills than later born siblings. The current study revealed that the resource dilution model, i.e., the decrease in resources for every additional sibling, holds for second language acquisition. Moreover, the results indicate that bilingual children from families with several children benefit from access to early education institutions.

  9. Monopoles in non-Abelian Born-Infeld-Higgs theory and Born-Infeld collapse

    Science.gov (United States)

    Dyadichev, V. V.; Gal'Tsov, D. V.

    2002-06-01

    Regular magnetic monopoles in the non-Abelian Born-Infeld-Higgs theory are known to exist in the region of the field strength parameter β>βcr, bounded from below. Beyond this region, only pointlike (embedded Abelian) monopoles exist, and we show that the transition from the regular to singular structure is reminiscent of gravitational collapse. Near the threshold behavior is characterized by the rapidly increasing negative pressure, which typically arises in the high density non-Abelian Born-Infeld (NBI) matter. Another feature, shared by both the NBI and gravitating monopoles, is the existence of excited states, which can be thought of as bound states of monopoles and sphalerons. These are labeled by the number N of nodes of the Yang-Mills function. Their masses are greater than the mass of the ground state monopole, and they are expected to be unstable. The sequence of masses MN rapidly converges to the mass of the embedded Abelian solution with a constant Higgs boson. The ratio of the sphaleron size to that of the monopole grows with decreasing β, and, at the same time, both fall down until the solutions cease to exist, again exhibiting a collapse to the point-like monopole. The results are presented and compared both for the ordinary and the symmetrized trace NBI actions.

  10. Zones of emotional labour

    DEFF Research Database (Denmark)

    Strøbæk, Pernille Solveig

    2011-01-01

    The paper suggests that due to the difficult nature of their work public family law caseworkers are to be included in the definition of emotional labour even though they are omitted by Hochschild. Based upon a review of the structures involved in emotional labour an explorative qualitative study is...... put forth among 25 Danish public family law caseworkers. The study points to personal, professional, and social zones of emotional labour through which the caseworkers carry out their work. Emotional labour zones mark emotion structures that may be challenging due to complex emotional intersections...

  11. Grid zone drone

    OpenAIRE

    McCarthy, Clive; Cooper, Graham; Field, James; Thayne, Martyn; Vickers, Richard

    2014-01-01

    From 16th – 19th October 2014, co_LAB presented its newest creation, Grid Zone Drone, at Kinetica – an international exhibition providing a global platform for galleries, curatorial groups, design studios and artists working with new media art. 2014 marked the third consecutive year that the University of Lincoln has been represented at the global art fair. Grid Zone Drone represents a continuation of the group’s research into ‘drone culture’, and explores the detachment of the drone withi...

  12. Thin-shell wormholes in Einstein-Born-Infeld theory

    CERN Document Server

    Eiroa, Ernesto F

    2015-01-01

    We construct spherically symmetric thin-shell wormholes with a generalized Chaplygin gas at the throat, in Born-Infeld electrodynamics coupled to Einstein gravity. We analyze their stability under radial perturbations.

  13. Surface-Borne Time-of-Reception Measurements (STORM) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Invocon proposes the Surface-borne Time-Of-Reception Measurements (STORM) system as a method to locate the position of lightning strikes on aerospace vehicles....

  14. INCIDENCE OF NEONATAL HYPERBILIRUBINEMEA IN TERM NEW BORNS AT KBNTGH

    OpenAIRE

    Mujumdar; Siddaling; Preethi; Nabeel; Harshavardhan

    2015-01-01

    AIM AND SCOPE: We conducted this study to estimate the incidence of hyperbilirubinemia in term new born with birth weight >2.5 kgs born at neonatal care unit of KBNTGH, and to determine the underlying causes, which would be of value in identifying and implementing strategies to prevent morbidity from this condition. BACKGROUND: Management of hyperbilirubinemia remains a challenge for neonatal medicine because of the risk for serious neurological complications related to the to...

  15. Complex method for approximated solutions to Born-Infeld equation

    CERN Document Server

    Ferraro, Rafael

    2015-01-01

    We display the method to solve the Born-Infeld equation in the complex plane. As the exact solution is obtained in an implicit form, we turn it into an explicit form by means of a perturbative procedure which takes care of secular behaviors common to this kind of approximations. We apply the method to build solutions to Born-Infeld electrodynamics. In particular, we study BI electromagnetic waves at interfaces, with the aim of searching for effects susceptible of experimental detection.

  16. Ray-Born Modelling and Full Waveform Inversion

    OpenAIRE

    Tengesdal, Hans Christian

    2013-01-01

    Seismic forward modelling is used to simulate seismic wave propagation in the subsurface. Common modelling techniques include methods such as the ray-Born approximation and the finite difference method. In this thesis I present a comparison between the ray-Born approximation and the finite difference method. This comparison consists of computing synthetic seismograms using both methods for several seismic velocity models and performing a comparison between them. The main ...

  17. Transmission mechanisms of an emerging insect-borne rickettsial pathogen

    OpenAIRE

    Brown, Lisa D.; Kaikhushroo H Banajee; Lane D Foil; Macaluso, Kevin R.

    2016-01-01

    Background Vector-borne pathogens must overcome arthropod infection and escape barriers (e.g. midgut and salivary glands) during the extrinsic incubation period (EIP) before subsequent transmission to another host. This particular timespan is undetermined for the etiological agent of flea-borne spotted fever (Rickettsia felis). Artificial acquisition of R. felis by blood-feeding cat fleas revealed dissemination to the salivary glands after seven days; however, this length of time is inconsist...

  18. Heat Engines for Dilatonic Born-Infeld Black Holes

    CERN Document Server

    Bhamidipati, Chandrasekhar

    2016-01-01

    In the context of dilaton coupled Einstein gravity with negative cosmological constant and a Born-Infeld field, we study heat engines where charged black hole is the working substance and the mechanical work is done via the $pdV$ terms present in the first law of extended gravitational thermodynamics. Efficiency is analyzed as a function of dilaton and Born-Infeld couplings, and results compared with Einstein-Maxwell theory.

  19. Magic moment? Maternal marriage for children born out of wedlock.

    Science.gov (United States)

    Gibson-Davis, Christina

    2014-08-01

    To test the existence of the "magic moment" for parental marriage immediately post-birth and to inform policies that preferentially encourage biological over step parent marriage, this study estimates the incidence and stability of maternal marriage for children born out of wedlock. Data came from the National Survey of Family Growth on 5,255 children born non maritally. By age 15, 29 % of children born non maritally experienced a biological-father marriage, and 36 % experienced a stepfather marriage. Stepfather marriages occurred much later in a child's life-one-half occurred after the child turned age 7-and had one-third higher odds of dissolution. Children born to black mothers had qualitatively different maternal marriage experiences than children born to white or Hispanic mothers, with less biological-parent marriage and higher incidences of divorce. Findings support the existence of the magic moment and demonstrate that biological marriages were more enduring than stepfather marriages. Yet relatively few children born out of wedlock experienced stable, biological-parent marriages as envisioned by marriage promotion programs.

  20. Air travel and vector-borne disease movement.

    Science.gov (United States)

    Tatem, A J; Huang, Z; Das, A; Qi, Q; Roth, J; Qiu, Y

    2012-12-01

    Recent decades have seen substantial expansions in the global air travel network and rapid increases in traffic volumes. The effects of this are well studied in terms of the spread of directly transmitted infections, but the role of air travel in the movement of vector-borne diseases is less well understood. Increasingly however, wider reaching surveillance for vector-borne diseases and our improving abilities to map the distributions of vectors and the diseases they carry, are providing opportunities to better our understanding of the impact of increasing air travel. Here we examine global trends in the continued expansion of air transport and its impact upon epidemiology. Novel malaria and chikungunya examples are presented, detailing how geospatial data in combination with information on air traffic can be used to predict the risks of vector-borne disease importation and establishment. Finally, we describe the development of an online tool, the Vector-Borne Disease Airline Importation Risk (VBD-Air) tool, which brings together spatial data on air traffic and vector-borne disease distributions to quantify the seasonally changing risks for importation to non-endemic regions. Such a framework provides the first steps towards an ultimate goal of adaptive management based on near real time flight data and vector-borne disease surveillance. PMID:22444826

  1. Interseismic deformation of the Shahroud fault system (NE Iran) from space-borne radar interferometry measurements

    Science.gov (United States)

    Mousavi, Z.; Pathier, E.; Walker, R. T.; Walpersdorf, A.; Tavakoli, F.; Nankali, H.; Sedighi, M.; Doin, M.-P.

    2015-07-01

    The Shahroud fault system is a major active structure in the Alborz range of NE Iran whose slip rate is not well constrained despite its potential high seismic hazard. In order to constrain the slip rate of the eastern Shahroud fault zone, we use space-borne synthetic aperture radar interferometry with both ascending and descending Envisat data to determine the rate of interseismic strain accumulation across the system. We invert the slip rate from surface velocity measurements using a half-space elastic dislocation model. The modeling results are consistent with a left-lateral slip rate of 4.75 ± 0.8 mm/yr on the Abr and Jajarm, strands of the Shahroud fault, with a 10 ± 4 km locking depth. This is in good agreement with the 4-6 mm/yr of left-lateral displacement rate accumulated across the total Shahroud fault system obtained from GPS measurements.

  2. DNS zones revisited

    NARCIS (Netherlands)

    Wanrooij, van Ward; Pras, Aiko; Delgado Kloos, Carlos

    2005-01-01

    Recent research [Pap04b] suggests DNS reliability and performance is not up to the levels it should be due to misconfigurations. This paper checks the configuration of nameserver zones against additional requirements, recommendations and best-practices. It shows that almost one in four domains fails

  3. Evaluation of the antibacterial activity of essential oil and aqueous and ethanolic extracts of Quercus infectoria leaves on food-borne pathogenic bacteria.

    Directory of Open Access Journals (Sweden)

    Nabi Shariatifar

    2014-10-01

    Full Text Available Food-borne pathogens are group of micro-organisms that cause food-borne illness thus, the research for finding effective natural product against this infection is necessary. The purpose of this study was to determine antibacterial activity of essential oil and ethanolic and aqueous extracts Quercus infectoria against some important food borne bacteria. In this study, antibacterial activity of extracts and essential oil was evaluated against bacteria (Escherichia coli, Staphylococcus aureus, Bacillus cereus, Yersinia entercolitica, Salmonella typhi and Vibrio cholera using disc diffusion method. Then broth micro-dilution method was used to determine their minimal inhibitory concentration (MIC and minimal bactericidal concentration (MBC. The data was expressed as the mean and the standard deviation; and they were statistically analyzed by ANOVA using SPSS software (P<0.05. Result showed that ethanol extract of Quercus infectoria was found to be the most effective against B. cereus strains (inhibition zone=16.85±0.65 mm than Yersinia entercolitica strains (inhibition zone=14.15 ±0.75mm. Aqueous extract of Quercus infectoria was found to be the most effective against B. cereus strains (inhibition zone=7.25±0.45 mm than Yersinia entercolitica strains (inhibition zone=14.45 ±0.21mm. The MIC values of the essential oil, ethanolic and aqueous extracts against B. cereus were 0.064, 0.512, 0.256 μg/ml and against salmonella typhi were 0.256, 0.1024, 0.1024μg/ml, respectively. Essential oil and extracts of Quercus infectoria leave showed a good antimicrobial activity against food borne pathogens. Therefore, they can be used in food preservation systems to inhibit the growth of these bacteria and improve food quality and safety.

  4. Empowerment Zones and Enterprise Districts - MDC_EnterpriseZone

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Polygon feature class of Miami Dade County Enterprise Zones. Enterprise Zones are special areas in the county where certain incentives from the State are available...

  5. ZONE OF COOPERATION

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The China-ASEAN Economic Zone is attracting more and more investors from both Southeast Asia and China Compared with other countries that have established free trade areas with ASEAN, China owns millions of unique advantages. Millions, after all, is the quantity of Chinese living in ASEAN countries. "With ties of blood, geography and commerce, business people of Chinese descent can be the best candidates to pro-

  6. Cape Verde Frontal Zone

    OpenAIRE

    Zenk, Walter; Klein, Birgit; Schröder, Michael

    1991-01-01

    The term Cape Verde Frontal Zone is introduced to characterize the southeastern corner of the subtropical gyre circulation in the North Atlantic Ocean far west of the upwelling area off the Mauretanean shelf. Two water mass fronts, one overlying the other, are identified with a quasi-synoptic set of CTD-OZ and nutrient data from November 1986. In the warm water sphere we encounter North and South Atlantic Central Water (NACWISACW) superimposed on extensions of Mediterranean outflow and Antarc...

  7. The uncomfortable comfort zone

    Directory of Open Access Journals (Sweden)

    Carlos Renato Zacharias

    2012-04-01

    Full Text Available Whenever we achieve the satisfaction of our expectations and anxiety dissolves, we feel as if we were in a comfort zone – safe, complete, free from risks and in peace with ourselves. We might even have a little taste of heaven when we feel that we have fulfilled our duty. And as a fact, scientists are entitled to this kind of reward… but not for too long! In science, to enter a comfort zone can be as pleasant as dangerous. On one hand we may have a safe ground available to develop new modes of reasoning, protocols and theories. And on the other, we may stay stuck in a conventional but fragile ground, missing opportunities to reveal novel secrets or to address edge issues. ... The community of HD researchers seems to have entered a new comfort zone when nanostructures were found in HD. Nanostructures have been raised to the level of ultimate evidence doing away with Avogadro’s limit and leading homeopathy and HD research into mainstream science. We really should enjoy this moment and collect more information about the HD phenomenon. However, we must be wary to not fall into a trap.

  8. Differential regulation of cell proliferation in neurogenic zones in mice lacking cystine transport by xCT

    International Nuclear Information System (INIS)

    The cystine/glutamate exchanger (xCT) supplies intracellular cyst(e)ine for the production of glutathione, a major cellular anti-oxidant. xCT is enriched in brain regions associated with neurogenesis. Previous studies have shown that the malfunction of this protein greatly attenuates cell proliferation in vitro and is associated with brain atrophy in vivo. Using mice that are homozygous for a function-blocking deletion in xCT (Sut mice), we examined in vivo the role of xCT in cell proliferation in neurogenic regions of the subventricular zone (SVZ) and denate gyrus (DG) in the adult brain. Our results indicate that a high level of cellular proliferation in the adult brain persists even in the absence of functional xCT. Furthermore, in both young adult and middle-aged mice (3 and 11 months old), rates of SVZ cell proliferation were comparable between Sut and wild-type controls, although there was trend towards reduced proliferation in Sut mice (12% and 9% reduction, respectively). To our surprise, rates of cell proliferation in the DG were elevated in both 3- and 11-month-old Sut mice relative to controls (22% and 28% increase, respectively). These results demonstrate that xCT expression plays a role in regulating cellular proliferation in the DG, but not the SVZ of adult mice. Furthermore, unlike previous in vitro studies, our in vivo observations clearly indicate that xCT is not essential for ongoing cellular proliferation

  9. Blasting of broken marble zones

    OpenAIRE

    Dambov, Risto; Stojceski, Igor; Dambov, Ilija

    2015-01-01

    On receipt of marble blocks appear deformed zones with presence of cracks and other deformities and very small cracks with different azimuth in the rocky massif. The fastest and economical way to bring this zone are removed by applying the methods of blasting. Before blasting, these tables - zones are limited by the block, making the cuts with diamond wire because explosive action may cause of surrounding quality marble blocks. Keywords: blasting, crashed zones, cracks, marble ...

  10. Firms' degree of born-globalness, international entrepreneurial orientation and export performance

    DEFF Research Database (Denmark)

    Servais, Per; Kuivalainen, Olli; Sundqvist, Sanna

    2007-01-01

    Despite the recent increase in 'born-global' studies, there has been little research on how the scale and scope of being a born-global firm affects performance: most of the earlier research takes no account either the number of or the distances between the countries on firm or export performance....... This article begins with a review of the existing literature on born-globals, and subsequently explores the relationship between entrepreneurial orientation (EO) and two different born-global strategies, namely true born-global and apparently born-global (born-international), and the effectiveness of these two...... born-global pathways. The results of our empirical study on 185 Finnish exporting firms show that those that qualified as true born-globals had better export performance. Furthermore, depending on the degree of born-globalness, different dimensions of EO were of importance....

  11. Born reciprocity in string theory and the nature of spacetime

    International Nuclear Information System (INIS)

    After many years, the deep nature of spacetime in string theory remains an enigma. In this Letter we incorporate the concept of Born reciprocity in order to provide a new point of view on string theory in which spacetime is a derived dynamical concept. This viewpoint may be thought of as a dynamical chiral phase space formulation of string theory, in which Born reciprocity is implemented as a choice of a Lagrangian submanifold of the phase space, and amounts to a generalization of T-duality. In this approach the fundamental symmetry of string theory contains phase space diffeomorphism invariance and the underlying string geometry should be understood in terms of dynamical bi-Lagrangian manifolds and an apparently new geometric structure, somewhat reminiscent of para-quaternionic geometry, which we call Born geometry.

  12. Developmental delay at 12 months in children born extremely preterm

    DEFF Research Database (Denmark)

    Lando, Ane; Klamer, Anja; Jonsbo, Finn;

    2005-01-01

    AIM: To evaluate the feasibility and validity of a structured telephone interview to assess the development of children born extremely preterm. METHODS: The parents of 88 children born with a gestational age below 28 wk admitted to the neonatal intensive care unit (NICU) at Rigshospitalet......, Copenhagen, were interviewed by telephone when their child was 1 y of age, corrected for preterm birth. A fully structured questionnaire on psychomotor function was used (Revised Prescreening Developmental Questionnaire (R-PDQ)). The parents of 30 children born at term without complications were interviewed...... for comparison. The interview was conducted by NICU staff. To validate the R-PDQ, parents of 22 children in the preterm group and parents of 19 children in the reference group conducted an Ages and Stages Questionnaire (ASQ) when their children had reached the age of 3-3(1/2) y. RESULTS: The R-PDQ was easy...

  13. Oral health of children born small for gestational age.

    LENUS (Irish Health Repository)

    O'Connell, A C

    2010-10-01

    We sought to evaluate the oral health status of children born small for gestational age (SGA). Children now aged 4-8 years who were born SGA (birth weight < -2 SDS) were examined using standardised criteria. The parents completed a structured oral health questionnaire. Twenty females and 25 males, mean age 72.1 months, and mean birth weight 2.1 kg, participated in the study. Poor appetite was a concern; 32 (71%) children snacked between meals and 14 (30%) used carbonated beverages more than 3 times daily. Erosion was present in 9 (20%) children. Dental decay occurred in 22 (47%) children with 92% being untreated. Eight children had more than 5 decayed teeth. It is essential that clinicians working with children born SGA include oral health within the general health surveillance and refer these children for a dental assessment within the first 2 years to support parents in establishing safe feeding patterns for their children.

  14. Born approximation in linear-time invariant system

    CERN Document Server

    Gumjudpai, Burin

    2015-01-01

    Linear-time invariant (LTI) oscillation systems such as forced mechanical vibration, series RLC and parallel RLC circuits can be solved by using simplest initial conditions or employing of Green's function of which knowledge of initial condition of the force term is needed. Here we show a mathematical connection of the LTI system and the Helmholtz equation form of the time-independent Schr\\"{o}dinger equation in quantum mechanical scattering problem. We apply Born approximation in quantum mechanics to obtain LTI general solution in form of infinite Born series which can be expressed as a series of one-dimensional Feynman graphs. Conditions corresponding to the approximation are given for the case of harmonic driving force. The Born series of the harmonic forced oscillation case are derived by directly applying the approximation to the LTI system or by transforming the LTI system to Helmholtz equation prior to doing the approximation.

  15. Born reciprocity in string theory and the nature of spacetime

    Energy Technology Data Exchange (ETDEWEB)

    Freidel, Laurent, E-mail: lfreidel@perimeterinstitute.ca [Perimeter Institute for Theoretical Physics, 31 Caroline St., N, Ontario N2L 2Y5, Waterloo (Canada); Leigh, Robert G., E-mail: rgleigh@uiuc.edu [Department of Physics, University of Illinois, 1110 West Green St., Urbana, IL 61801 (United States); Minic, Djordje, E-mail: dminic@vt.edu [Department of Physics, Virginia Tech, Blacksburg, VA 24061 (United States)

    2014-03-07

    After many years, the deep nature of spacetime in string theory remains an enigma. In this Letter we incorporate the concept of Born reciprocity in order to provide a new point of view on string theory in which spacetime is a derived dynamical concept. This viewpoint may be thought of as a dynamical chiral phase space formulation of string theory, in which Born reciprocity is implemented as a choice of a Lagrangian submanifold of the phase space, and amounts to a generalization of T-duality. In this approach the fundamental symmetry of string theory contains phase space diffeomorphism invariance and the underlying string geometry should be understood in terms of dynamical bi-Lagrangian manifolds and an apparently new geometric structure, somewhat reminiscent of para-quaternionic geometry, which we call Born geometry.

  16. The Alliance Capability of Technology-Based Born Globals

    DEFF Research Database (Denmark)

    Oxtorp, Liliya Altshuler; Elg, Ulf

    2015-01-01

    A detailed investigation of the aspects comprising the alliance capability of technology-based born globals. Alliance capability is regarded as a set of organizational skills necessary from the decision to search for a partner for a technology collaboration, which may also involve a marketing...... aspect, through initiation and management of the alliance, up until its objectives are achieved, or otherwise. Originality/value of paper: While earlier research discussed networking and alliance strategies of born globals on a strategic level, this paper investigates and analyses the specific...... and risks of collaborating with MNEs.Methodology: A longitudinal process study of a Danish technology born global with three embedded cases of its R&D and marketing alliances with Asian MNEs.Findings: The organisational skills comprising the alliance capability are defined to be internal and external...

  17. Smart antennas for space-borne synthetic aperture radars

    Science.gov (United States)

    Qin, F.; Gao, S.; Mao, C.; Wang, Z.; Patyuchenko, A.; Younis, M.; Krieger, G.

    2015-11-01

    This paper discusses smart antennas for space-borne synthetic aperture radar (SAR). First, some recent development in smart antennas for space-borne SAR is reviewed. Then, the paper presents a low-cost space-borne SAR system using digital beam forming on receive. The smart antenna system is also discussed, and some results are shown. The antenna system, consisting of a parabolic reflector and multi-feed array, is designed and optimized for dual-band dual-polarized digital beam-forming performance. The operating frequencies are at X and Ka bands with the center frequency of 9.6 and 35.75 GHz, respectively. The stacked dipoles and square patches with parasitic elements are employed as the feed elements at X and Ka bands. Dual-band antenna arrays are combined in the same aperture, which not only reduce the aperture of the feed array, but also coincide the center of dual-band feed arrays.

  18. Quantum probabilities from quantum entanglement: experimentally unpacking the Born rule

    Science.gov (United States)

    Harris, Jérémie; Bouchard, Frédéric; Santamato, Enrico; Zurek, Wojciech H.; Boyd, Robert W.; Karimi, Ebrahim

    2016-05-01

    The Born rule, a foundational axiom used to deduce probabilities of events from wavefunctions, is indispensable in the everyday practice of quantum physics. It is also key in the quest to reconcile the ostensibly inconsistent laws of the quantum and classical realms, as it confers physical significance to reduced density matrices, the essential tools of decoherence theory. Following Bohr’s Copenhagen interpretation, textbooks postulate the Born rule outright. However, recent attempts to derive it from other quantum principles have been successful, holding promise for simplifying and clarifying the quantum foundational bedrock. A major family of derivations is based on envariance, a recently discovered symmetry of entangled quantum states. Here, we identify and experimentally test three premises central to these envariance-based derivations, thus demonstrating, in the microworld, the symmetries from which the Born rule is derived. Further, we demonstrate envariance in a purely local quantum system, showing its independence from relativistic causality.

  19. Cross sections for electron-hydrogen collisions in the Born approximation to the reactance matrix

    International Nuclear Information System (INIS)

    Born partial-wave integrals have been performed for a range of energies and total cross sections are presented for electron-hydrogen-atom excitation both in the conventional first Born approximation (Born I) and the unitarised Born approximation (Born II). Exchange effects are not included. With the exception of exact resonance-allowed transitions (n = n', lambda = 1) results are presented for all transitions between hydrogen-atom states whose principal quantum number is less than or equal to 4. (author)

  20. Excessive Daytime Sleepiness among Hypertensive US-Born Blacks and Foreign-Born Blacks: Analysis of the CAATCH Data

    Directory of Open Access Journals (Sweden)

    N. Williams

    2013-01-01

    Full Text Available Background. Evidence shows that blacks exhibit greater daytime sleepiness compared with whites, based on the Epworth Sleepiness Scale. In addition, sleep complaints might differ based on individuals’ country of origin. However, it is not clear whether individuals’ country of origin has any influence on excessive daytime sleepiness (EDS. Study Objectives. We tested the hypothesis that US-born blacks would show a greater level of EDS compared with foreign-born blacks. The potential effects of sociodemographic and medical risk were also determined. Design. We used the Counseling African-Americans to Control Hypertension (CAATCH data. CAATCH is a group randomized clinical trial that was conducted among 30 community healthcare centers in New York, yielding baseline data for 1,058 hypertensive black patients. Results. Results of univariate logistic regression analysis indicated that US-born blacks were nearly twice as likely as their foreign-born black counterparts to exhibit EDS (OR=1.87, 95% CI: 1.30–2.68, P<0.001. After adjusting for effects of age, sex, education, employment, body mass index, alcohol consumption, and smoking habit, US-born blacks were 69% more likely than their counterparts to exhibit EDS (OR=1.69, 95% CI: 1.11–2.57, P<0.01. Conclusion. Findings demonstrate the importance of considering individuals’ country of origin, in addition to their race and ethnicity, when analyzing epidemiologic sleep data.

  1. Emerging vector borne diseases – incidence through vectors

    Directory of Open Access Journals (Sweden)

    Sara eSavic

    2014-12-01

    Full Text Available Vector borne diseases use to be a major public health concern only in tropical and subtropical areas, but today they are an emerging threat for the continental and developed countries also. Nowdays, in intercontinetal countries, there is a struggle with emerging diseases which have found their way to appear through vectors. Vector borne zoonotic diseases occur when vectors, animal hosts, climate conditions, pathogens and susceptible human population exist at the same time, at the same place. Global climate change is predicted to lead to an increase in vector borne infectious diseases and disease outbreaks. It could affect the range and popultion of pathogens, host and vectors, transmission season, etc. Reliable surveilance for diseases that are most likely to emerge is required. Canine vector borne diseases represent a complex group of diseases including anaplasmosis, babesiosis, bartonellosis, borreliosis, dirofilariosis, erlichiosis, leishmaniosis. Some of these diseases cause serious clinical symptoms in dogs and some of them have a zoonotic potential with an effect to public health. It is expected from veterinarians in coordination with medical doctors to play a fudamental role at primeraly prevention and then treatment of vector borne diseases in dogs. The One Health concept has to be integrated into the struggle against emerging diseases.During a four year period, from 2009-2013, a total number of 551 dog samples were analysed for vector borne diseases (borreliosis, babesiosis, erlichiosis, anaplasmosis, dirofilariosis and leishmaniasis in routine laboratory work. The analysis were done by serological tests – ELISA for borreliosis, dirofilariosis and leishmaniasis, modified Knott test for dirofilariosis and blood smear for babesiosis, erlichiosis and anaplasmosis. This number of samples represented 75% of total number of samples that were sent for analysis for different diseases in dogs. Annually, on avarege more then half of the samples

  2. Neurosensory outcome of prematurely born children following intracranial hemorrhage

    Directory of Open Access Journals (Sweden)

    Velisavljev-Filipović Gordana

    2011-01-01

    Full Text Available Introduction. More and more survival of newborns with small or extremely small body mass at birth, as well as increasing percent of prematurely born babies, have emphasized the significance of intracranial haemorrhage problem. Prematurely born infants are under increased risk for strabismus, amblyopia, blinding and hearing loss. Objective. Establishing the frequency of sensory damages (damage of sight and hearing in prematurely born infants with various degrees of intracranial haemorrhage. Methods. The study is prospective, controlled and included 120 prematurely born infants with diagnosed four different grade intracranial haemorrhage on ultrasonic examination of the central nervous system. The study excluded prematurely born children from twin pregnancies with congenital malformations and stoppage of intrauterine growth. Ophthalmological examination was done at 9, 12, and 36 months of postnatal age. Audilogical examination was done after delivery, at 2 months of age. Results. There are statistically significant differences (p<0.01 related to the presence of strabismus among groups of examinees with vairious hemorrhage degrees. Strabismus was present only in one premature infant with 1st and in 10 children (33.3% with the 4th degree. Amblyopia occurred only among examinees with 4th degree hemorrhage. There were statistically significant differences (p<0.01 related to the finding of transitory otoacoustic emission of the left ear and the right ear among the groups. The finding of the right ear was not usual in 7 examinees from the 4th degree hemorrhage. The finding of the left ear was not usual in 1 examinee from the third and in 7 examinees from the fourth group. Conclusion. Prematurely born children with a higher degree intracranial hemorrhage have a greater risk for the loss of hearing and development of visual handicap.

  3. Ethnic Identity and Its Relation to Personal Self-Esteem: A Comparison of Canadian-Born and Foreign-Born Chinese Adolescents.

    Science.gov (United States)

    Lay, Clarry; Verkuyten, Maykel

    1999-01-01

    Examines ethnic identity and its relation to personal self-esteem by comparing Chinese adolescents who immigrated to Canada and Canadian-born Chinese adolescents. Finds that aspects of collective self-esteem were positively related to personal self-esteem for the foreign-born group, not the Canadian-born group. (CMK)

  4. Perceived Job Skill Limitations and Participation in Education and Training Opportunities: Differences between Us Native-Born and Non-Native-Born Individuals

    Science.gov (United States)

    Smith, M. Cecil; Smith, Thomas J.

    2010-01-01

    Data from the 2003 National Assessment of Adult Literacy were examined to determine if non-native-born adults in the US differ from their native-born counterparts in (1) participation in work-related training or education, and (2) perceptions that specific skills limit their job opportunities. Results indicated that non-native-born persons were…

  5. On the NUT-Born-Infeld-$\\Lambda$ spacetime

    CERN Document Server

    Bretón, Nora

    2014-01-01

    The stationary axisymmetric spacetime coupled to nonlinear Born-Infeld electrodynamics is studied. The solution was derived by Plebanski et al (1984) and it is characterized by six free parameters: mass, NUT charge, electric and magnetic charge, Born-Infeld parameter and cosmological constant. The geodesic and Lorentz force equations are integrated, and a qualitative analysis of the effect of varying the parameters in the effective potential is provided. Then the light and charged particle trajectories are discussed. The conditions that determine an extreme black hole are presented as well.

  6. Atopic diseases in twins born after assisted reproduction

    DEFF Research Database (Denmark)

    Jäderberg, Ida; Thomsen, Simon F; Kyvik, Kirsten Ohm;

    2012-01-01

    and variance components analysis. Children born after assisted reproduction did not have a different risk of atopic outcomes (adjusted odds ratios [95% confidence intervals] for asthma: 0.95 [0.85, 1.07], P = 0.403; hay fever: 1.01 [0.86, 1.18], P = 0.918; and atopic dermatitis: 1.02 [0.81, 1.11], P = 0.......773 respectively) compared with children born after spontaneous conception. Assisted reproduction did not modify the heritability of atopic diseases. This study does not support an association between assisted reproduction and development of atopic diseases. This result must be confirmed in subsequent studies...

  7. Thermodynamics of Third Order Lovelock-Born-Infeld Black Holes

    Institute of Scientific and Technical Information of China (English)

    李鹏; 岳瑞宏; 邹德成

    2011-01-01

    We here explore black holes in the third order Lovelock gravity coupling with nonlinear Born-Infeld electro- magnetic field. Considering special second and third order coefficients (&g = 363 = a2), we analyze the thermodynamics of third order Lovelock-Born-Infeld black holes and, in 7-dimensional AdS space-time, discuss the stability of black holes in different event horizon structures. We find that the cosmological constant A plays an important role in the distribution of black hole stable regions.

  8. Wormhole geometries in Eddington-Inspired Born-Infeld gravity

    Science.gov (United States)

    Harko, Tiberiu; Lobo, Francisco S. N.; Mak, M. K.; Sushkov, Sergey V.

    2015-10-01

    Eddington-inspired Born-Infeld (EiBI) gravity is a recently proposed modified theory of gravity, based on the classic work of Eddington and Born-Infeld nonlinear electrodynamics. In this paper, we consider the possibility that wormhole geometries are sustained in EiBI gravity. We present the gravitational field equations for an anisotropic stress-energy tensor and consider the generic conditions, for the auxiliary metric, at the wormhole throat. In addition to this, we obtain an exact solution for an asymptotically flat wormhole.

  9. Anxiety in adolescents born preterm or with very low birthweight

    DEFF Research Database (Denmark)

    Sømhovd, Mikael Julius; Hansen, Bo Mølholm; Brok, Jesper Sune;

    2012-01-01

    Aim To determine if adolescents who are born very preterm (... of identified articles. We selected casecontrol studies of adolescents 11 to 20 years old who were very preterm/VLBW and had a matched reference group born at term with normal birthweight that reported a validated anxiety outcome measure. For data extraction, two authors independently reviewed titles, abstracts......, and full articles identified through the searches. Subsequently two authors independently extracted data. Results We included six studies with 1519 adolescents (787 very preterm/VLBW, 732 comparisons). The general risk of developing clinically significant anxiety problems was nearly doubled (p

  10. Development and Potential of Space-Borne Doppler Wind Lidar

    Institute of Scientific and Technical Information of China (English)

    LIU Zhishen; SUN Dapeng; WU Dong; Juergen Streicher; Ines Leike

    2003-01-01

    The advantage of lidar over other wind sensors is presented in this paper. With more than 20 years research, the development of the space-borne wind lidar is reviewed. Longer-term investigation has made many technologies suitable for the wind lidar measurement from an orbital platform become mature. However, there are still some problems to be solved. In order to obtain the optimal performance in wind detection, great importance is being attached to the simulation of a virtual space-borne wind lidar system on computer as developed by NASA and ESA.

  11. Dirac-Born-Infeld-Einstein theory with Weyl invariance

    CERN Document Server

    Maki, Takuya; Shiraishi, Kiyoshi

    2011-01-01

    Weyl invariant gravity has been investigated as the fundamental theory of the vector inflation. Accordingly, we consider a Weyl invariant extension of Dirac-Born-Infeld type gravity. We find that an appropriate choice of the metric removes the scalar degree of freedom which is at the first sight required by the local scale invariance of the action, and then a vector field acquires mass. Then nonminimal couplings of the vector field and curvatures are induced. We find that the Dirac-Born-Infeld type gravity is a suitable theory to the vector inflation scenario.

  12. Born-Infeld Type Extension of (Non-)Critical Gravity

    OpenAIRE

    Yi, Sang-Heon

    2012-01-01

    We consider the Born-Infeld type extension of (non-)critical gravity which is higher curvature gravity on Anti de-Sitter space with specific combinations of scalar curvature and Ricci tensor. This theory may also be viewed as a natural extension of three-dimensional Born-Infeld new massive gravity to arbitrary dimensions. We show that this extension is consistent with holographic $c$-theorem and scalar graviton modes are absent in this theory. After showing that ghost modes in the theory can ...

  13. Many Worlds, the Born Rule, and Self-Locating Uncertainty

    CERN Document Server

    Carroll, Sean M

    2014-01-01

    We provide a derivation of the Born Rule in the context of the Everett (Many-Worlds) approach to quantum mechanics. Our argument is based on the idea of self-locating uncertainty: in the period between the wave function branching via decoherence and an observer registering the outcome of the measurement, that observer can know the state of the universe precisely without knowing which branch they are on. We show that there is a uniquely rational way to apportion credence in such cases, which leads directly to the Born Rule. Our analysis generalizes straightforwardly to cases of combined classical and quantum self-locating uncertainty, as in the cosmological multiverse.

  14. Smartphones and Time Zones

    Science.gov (United States)

    Baird, William; Secrest, Jeffery; Padgett, Clifford; Johnson, Wayne; Hagrelius, Claire

    2016-09-01

    Using the Sun to tell time is an ancient idea, but we can take advantage of modern technology to bring it into the 21st century for students in astronomy, physics, or physical science classes. We have employed smartphones, Google Earth, and 3D printing to find the moment of local noon at two widely separated locations. By reviewing GPS time-stamped photos from each place, we are able to illustrate that local noon is longitude-dependent and therefore explain the need for time zones.

  15. Dairy Heifer Rearing in Hot Arid Zone: An Economic Assessment

    Directory of Open Access Journals (Sweden)

    M. A. Razzaque

    2010-01-01

    Full Text Available Problem statement: Economic losses due to high mortality in young calves born in hot arid zone including Kuwait and a high cost of rearing are the main constraints to this region. Therefore, dairy producers have to depend on importation of pregnant heifers for herd replacement. Research data on cost of heifer rearing from their weaning to first lactation were lacking. The objectives of the present investigation were to compare the costs/benefits of raising heifers born in Kuwait without and with intervention measures and project the future financial benefits. Approach: Present study methods involved using cost-benefit model where without and with intervention scenarios were compared using a total of 58 herd parameters. These variables included in the spreadsheets in the model could be varied during each year of projection period. Production turnoff of 3 herds each of 245 cows in three scenarios namely baseline, improved and future were evaluated. Input costs of imported heifers (baseline, locally raised heifers with interventions (improved and projected 10 year (future and the income generated from these scenarios were analyzed. Results: Total income generated from baseline, improved and the future projection were KD 268,715/-, 281,246/-and 342,251/-respectively (1 KD Kuwaiti Dinar = US $3.45; total operating costs of these scenarios were KD 249,372/-, 242,276/-and 205,929/-respectively. Financial analyses showed that benefits were double when interventions were applied KD 19,343/-Vs KD 38,970/-in baseline and improved operation respectively. Conclusion: Fifty percent of the total heifers needed for herd replacement could be sourced locally showing an increased net income as an outcome of intervention measures. Locally born adapted heifers could be used for dairying in this hot arid zone with a phase-wise increase in their herd size reducing dependence on imported dairy cattle.

  16. Parapapillary atrophy: histological gamma zone and delta zone.

    Directory of Open Access Journals (Sweden)

    Jost B Jonas

    Full Text Available BACKGROUND: To examine histomorphometrically the parapapillary region in human eyes. METHODOLOGY/PRINCIPAL FINDINGS: The histomorphometric study included 65 human globes (axial length:21-37 mm. On anterior-posterior histological sections, we measured the distance Bruch's membrane end (BME-optic nerve margin ("Gamma zone", BME-retinal pigment epithelium (RPE ("Beta zone", BME-beginning of non-occluded choriocapillaris, and BME-beginning of photoreceptor layer. "Delta zone" was defined as part of gamma zone in which blood vessels of at least 50 µm diameter were not present over a length of >300 µm. Beta zone (mean length:0.35±0.52 mm was significantly (P = 0.01 larger in the glaucoma group than in the non-glaucomatous group. It was not significantly (P = 0.28 associated with axial length. Beta zone was significantly (P = 0.004 larger than the region with occluded choriocapillaris. Gamma zone (mean length:0.63±1.25 mm was associated with axial length (P50 µm diameter within gamma zone was present only in highly axially elongated globes and was not related with glaucoma. Beta zone (Bruch's membrane without RPE was correlated with glaucoma but not with globe elongation. Since the region with occluded choriocapillaris was smaller than beta zone, complete loss of RPE may have occurred before complete choriocapillaris closure.

  17. Trends and Disparities in Mortality Among Spanish-Born and Foreign-Born Populations Residing in Spain, 1999–2008

    OpenAIRE

    Moncho, Joaquin; Pereyra Zamora, Pamela; Nolasco, Andreu; Tamayo Fonseca, Nayara; Melchor-Alós, Inmaculada; Maciá Soler, Loreto

    2015-01-01

    Spain’s immigrant population has increased 380 % in the last decade, accounting for 13.1 % of the total population. This fact has led her to become during 2009 the eighth recipient country of international immigrants in the world. The aim of this article is to describe the evolution of mortality and the main causes of death among the Spanish-born and foreign-born populations residing in Spain between 1999 and 2008. Age-standardised mortality rates (ASRs), average age and comparative mortality...

  18. Singular inflation from Born-Infeld-f(R) gravity

    CERN Document Server

    Elizalde, Emilio

    2016-01-01

    Accelerating dynamics from Born-Infeld-$f(R)$ gravity are studied in a simplified conformal approach without matter. Explicit unification of inflation with late-time acceleration is realized within this singular inflation approach, which is similar to Odintsov-Oikonomou singular $f(R)$ inflation. Our model turns out to be consistent with the latest release of Planck data.

  19. The Well-Being of Children Born to Teen Mothers

    Science.gov (United States)

    Levine, Judith A.; Emery, Clifton R.; Pollack, Harold

    2007-01-01

    Children born to early child bearers are more likely than other children to display problem behaviors or poor academic performance, but it is unclear whether early childbearing plays a causal role in these outcomes. Using multiple techniques to control for background factors, we analyze 2,908 young children and 1,736 adolescents and young adults…

  20. Towards a Supersymmetric Non-Abelian Born-Infeld Theory

    NARCIS (Netherlands)

    Bergshoeff, E.A.; Roo, M. de; Sevrin, A.

    2001-01-01

    We define an iterative procedure to obtain a non-abelian generalization of the Born-Infeld action. This construction is made possible by the use of the severe restrictions imposed by kappa-symmetry. We have calculated all bosonic terms in the action up to terms quartic in the Yang-Mills field streng

  1. Risk Factors for Retinopathy of Prematurity in Premature Born Children

    OpenAIRE

    Alajbegovic-Halimic, Jasmina; Zvizdic, Denisa; Alimanovic-Halilovic, Emina; Dodik, Irena; Duvnjak, Sanela

    2015-01-01

    Introduction: Retinopathy of Prematurity (ROP) represent disease of the eye in premature born children which affects immature blood vessels of the retina during their development. The emergence of retinopathy of prematurity depends on the interaction of multiple factors, such as: gestational age, low birth weight, hypoxia, duration of oxygen supplementation, respiratory distress syndrome, twin pregnancy, anemia, blood transfusions, sepsis, intraventricular hemorrhage, hypotension, hypothermia...

  2. The accidental internationalists : A theory of born globals

    NARCIS (Netherlands)

    Hennart, J.M.A.

    2014-01-01

    The distinguishing characteristic of international new ventures/born globals (INVs/BGs) is that they have foreign sales from the outset, or very quickly afterward. I argue that this is due to their business model. INVs/BGs sell to spatially dispersed customers distinctive niche products that incur l

  3. On Born's deformed reciprocal complex gravitational theory and noncommutative gravity

    International Nuclear Information System (INIS)

    Born's reciprocal relativity in flat spacetimes is based on the principle of a maximal speed limit (speed of light) and a maximal proper force (which is also compatible with a maximal and minimal length duality) and where coordinates and momenta are unified on a single footing. We extend Born's theory to the case of curved spacetimes and construct a deformed Born reciprocal general relativity theory in curved spacetimes (without the need to introduce star products) as a local gauge theory of the deformed Quaplectic group that is given by the semi-direct product of U(1,3) with the deformed (noncommutative) Weyl-Heisenberg group corresponding to noncommutative generators [Za,Zb]≠0. The Hermitian metric is complex-valued with symmetric and nonsymmetric components and there are two different complex-valued Hermitian Ricci tensors Rμν,Sμν. The deformed Born's reciprocal gravitational action linear in the Ricci scalars R,S with Torsion-squared terms and BF terms is presented. The plausible interpretation of Zμ=EμaZa as noncommuting p-brane background complex spacetime coordinates is discussed in the conclusion, where Eμa is the complex vielbein associated with the Hermitian metric Gμν=g(μν)+ig[μν]=EμaE-barνbηab. This could be one of the underlying reasons why string-theory involves gravity

  4. Transmission ecology of rodent-borne diseases: New frontiers.

    Science.gov (United States)

    Bordes, Frédéric; Blasdell, Kim; Morand, Serge

    2015-09-01

    Rodents are recognized reservoir hosts for many human zoonotic pathogens. The current trends resulting from anthropocene defaunation suggest that in the future they, along with other small mammals, are likely to become the dominant mammals in almost all human-modified environments. Recent intricate studies on bat-borne emerging diseases have highlighted that many gaps exist in our understanding of the zoonotic transmission of rodent-borne pathogens. This has emphasized the need for scientists interested in rodent-borne diseases to integrate rodent ecology into their analysis of rodent-borne pathogen transmission in order to identify in more detail the mechanisms of spillover and chains of transmission. Further studies are required to better understand the true impact of rodent abundance and the importance of pathogen sharing and circulation in multi-host- multi-pathogen communities. We also need to explore in more depth the roles of generalist and abundant species as the potential links between pathogen-sharing, co-infections and disease transmission. PMID:26176684

  5. Acrylic polymer nanocomposite resins for water borne coating applications

    NARCIS (Netherlands)

    Nobel, M.L.

    2007-01-01

    Due to environmental and safety regulations the use of volatile organic components (VOC's) containing lacquers for exterior automotive purposes is under growing pressure. As a consequence there is a demand for more environmentally friendly alternatives like water borne coatings, high solid coatings,

  6. Tick vaccines and the control of tick-borne pathogens.

    Science.gov (United States)

    Merino, Octavio; Alberdi, Pilar; Pérez de la Lastra, José M; de la Fuente, José

    2013-01-01

    Ticks are obligate hematophagous ectoparasites that transmit a wide variety of pathogens to humans and animals. The incidence of tick-borne diseases has increased worldwide in both humans and domestic animals over the past years resulting in greater interest in the study of tick-host-pathogen interactions. Advances in vector and pathogen genomics and proteomics have moved forward our knowledge of the vector-pathogen interactions that take place during the colonization and transmission of arthropod-borne microbes. Tick-borne pathogens adapt from the vector to the mammalian host by differential gene expression thus modulating host processes. In recent years, studies have shown that targeting tick proteins by vaccination can not only reduce tick feeding and reproduction, but also the infection and transmission of pathogens from the tick to the vertebrate host. In this article, we review the tick-protective antigens that have been identified for the formulation of tick vaccines and the effect of these vaccines on the control of tick-borne pathogens.

  7. Determinants of oral bioavailability of soil-borne contaminants

    NARCIS (Netherlands)

    Oomen, Agnes Guadalupe

    2001-01-01

    Children ingest soil, either accidentally via hand-to-mouth behavior or deliberately. In this manner, a child ingests on average between 50 and 200 mg soil/day, although amounts of as much as 60 g/day have also been observed. Hence, soil ingestion can be a main route of exposure to soil-borne

  8. Arthropod Borne Diseases in Imposed War during 1980-88

    Directory of Open Access Journals (Sweden)

    M Khoobdel

    2008-06-01

    Full Text Available Background: Personnel of military forces have close contact with natural habitat and usually encounter with bite of arthropods and prone to be infected with arthropod borne diseases. The imposed war against Iran was one of the most important and the longest war in the Middle East and even in the world and military people faced various diseases. The aim of this study was to review prevalence of arthropod borne diseases and to collect relevant information and valuable experiences during the imposed war.Methods: The present survey is a historical research and cross-sectional study, focused on arthropod fauna, situation of different arthropod borne diseases and also the ways which military personnel used to protect themselves against them. The information was adopted from valid military health files and also interviewing people who participated in the war.Results: Scabies, cutaneous leishmaniasis, sandfly fever and pediculosis were more prevalent among other arthropod -borne diseases in Iran-Iraq war. Measures to control arthropods and diseases at wartime mainly included: scheduled spraying of pesticides, leishmanization and treatment of patients.Conclusion: Although measures used during the war to control arthropods were proper, however, due to needs and importance of military forces to new equipment and technologies, it is recommended to use deltamethrin-impreg­nated bed net, permethrin treated military uniforms and various insect repellents in future.

  9. Tick vaccines and the transmission of tick-borne pathogens.

    Science.gov (United States)

    de la Fuente, J; Kocan, K M; Blouin, E F

    2007-08-01

    Ticks transmit pathogens that cause diseases which greatly impact both human and animal health. Vaccines developed against Boophilus spp. using Bm86 and Bm95 tick gut antigens demonstrated the feasibility of using vaccines for control of tick infestations. These vaccines also reduced transmission of tick-borne pathogens by decreasing exposure of susceptible hosts to ticks. The recently discovered tick antigens, 64P putative cement protein and subolesin involved in the regulation of tick feeding and reproduction, were also shown to reduce tick infestations. These antigens, together with the TROSPA receptor for Burrelia burgdorferi OspA were effective against tick-borne pathogens by reducing the infection levels in ticks and/or the transmission of the pathogen. Development of a vaccine targeted at both the tick vector and pathogen would contribute greatly to the control of tick infestations and the transmission of tick-borne diseases. These results have demonstrated that tick vaccines can be developed for control tick infestations and show promise for the prevention of the transmission of tick-borne pathogens. PMID:17682852

  10. Seed borne diseases - a challenge for organic cereal production

    OpenAIRE

    Borgen, Anders; Kristensen, Lars,

    2000-01-01

    Seed borne diseases are to be considered serious in organic agriculture, and direct seed treatment methods will some times be necessary. Hot water treatment, mustard extracts and acetic acid can provide efficient control methods. Discussions on the feasibility of the different methods in organic agriculture is needed.

  11. Born-Oppenheimer approximation for a harmonic molecule

    OpenAIRE

    Fernandez, Francisco M.

    2008-01-01

    We apply the Born-Oppenheimer approximation to a harmonic diatomic molecule with one electron. We compare the exact and approximate results not only for the internal degrees of freedom but also for the motion of the center of mass. We address the problem of identical nuclei and discuss other applications of the model and its limitations.

  12. The polarisation correction for space-borne grating spectrometers

    Science.gov (United States)

    Zhao, Fa-cai; Sun, Quan-she; Chen, Kun-feng; Zhu, Xing-bang; Wang, Shao-shui; Wang, Guo-quan; Zheng, Xiang-liang; Han, Zhong

    2014-02-01

    Satellite measurements of backscattered sunlight contain essential information about the global distribution of atmospheric constituents. Light reflected from the Earth's atmosphere is linearly or partially linearly polarized because of scattering of unpolarized sunlight by air molecules and aerosols. In the ultraviolet and visible part of the spectrum, measurements of space-borne grating spectrometers are in general sensitive to the state of polarization of the observed light. The interaction of polarized light with polarization-sensitive optical devices yields a different radiance that is measured by the detectors than the radiance that enters the instrument. In the OMI and the SBUV/2 instruments the problem of instrument polarization sensitivity is avoided because the polarized backscattered sunlight is depolarized before it interacts with the polarization-sensitive optical components. For GOME, SCIAMACHY, and GOME-2 it is intended to eliminate the polarization response of the instrument from the polarization-sensitive measurement. This paper discusses the basic concept of the polarisation correction of the space-borne grating spectrometers by using Mueller matrix calculus. A model was developed using the Mueller Matrices formulation to evaluate the polarization sensitivity of the space-borne grating spectrometers. The optical components are treated as general diattenuators with phase retardance. The correction for this polarization sensitivity is based on broadband polarization measurements. Accurate preflight polarisation calibration of space-borne grating spectrometers is essential for the observational objectives of the instrument, and a special facility has been developed in order to allow the instrument to be calibrated.

  13. Photosensitized inactivation of infectious blood-borne human parasites

    Science.gov (United States)

    Judy, Millard M.; Sogandares-Bernal, Franklin M.; Matthews, James Lester

    1995-05-01

    Blood-borne viruses and protozoan parasites that are infectious to humans pose risk world-wide of infection transmission through blood and blood product transfusion. Blood-borne infectious viruses include human immunodeficiency virus (HIV-I), which causes AIDS; hepatitis C virus, which can cause chronic hepatitis; and cytomegalovirus, which can be dangerous to immunocompromised patients, e.g., the newborn, transplant recipients, and AIDS patients. Infectious blood-borne protozoan parasites include Trypanosoma cruzi, which causes Chagas' disease, endemic throughout Central and South America; the Trypanosoma species causing African sleeping sickness endemic in Central Africa; and Plasmodium falciparum, which causes malignant and increasingly drug- resistant human malaria prevalent throughout the tropics. Some researchers have focused on using photosensitizers to inactivate HIV-I and other viruses in whole blood, packed red cells, and platelet concentrates without compromising blood product function. Our group previously has reported photosensitized in vitro inactivation of P. falciparum and the mouse malaria organism Plasmodium berghei in whole blood using hematoporphyrin derivative (HPD) and of T. cruzi using benzoporphyrin derivatives BPDMA and BPDDA, dihematoporphyrin ether (DHE), and hydroxyethylvinyldeuteroporphyrin (HEVD). These results suggest that continued investigation is warranted to evaluate the potential for photosensitized inactivation of blood-borne parasites in blood banking.

  14. Practical solutions to implementing "Born Semantic" data systems

    Science.gov (United States)

    Leadbetter, A.; Buck, J. J. H.; Stacey, P.

    2015-12-01

    The concept of data being "Born Semantic" has been proposed in recent years as a Semantic Web analogue to the idea of data being "born digital"[1], [2]. Within the "Born Semantic" concept, data are captured digitally and at a point close to the time of creation are annotated with markup terms from semantic web resources (controlled vocabularies, thesauri or ontologies). This allows heterogeneous data to be more easily ingested and amalgamated in near real-time due to the standards compliant annotation of the data. In taking the "Born Semantic" proposal from concept to operation, a number of difficulties have been encountered. For example, although there are recognised methods such as Header, Dictionary, Triples [3] for the compression, publication and dissemination of large volumes of triples these systems are not practical to deploy in the field on low-powered (both electrically and computationally) devices. Similarly, it is not practical for instruments to output fully formed semantically annotated data files if they are designed to be plugged into a modular system and the data to be centrally logged in the field as is the case on Argo floats and oceanographic gliders where internal bandwidth becomes an issue [2]. In light of these issues, this presentation will concentrate on pragmatic solutions being developed to the problem of generating Linked Data in near real-time systems. Specific examples from the European Commission SenseOCEAN project where Linked Data systems are being developed for autonomous underwater platforms, and from work being undertaken in the streaming of data from the Irish Galway Bay Cable Observatory initiative will be highlighted. Further, developments of a set of tools for the LogStash-ElasticSearch software ecosystem to allow the storing and retrieval of Linked Data will be introduced. References[1] A. Leadbetter & J. Fredericks, We have "born digital" - now what about "born semantic"?, European Geophysical Union General Assembly, 2014

  15. Bacterial food-borne pathogens in Indian food

    International Nuclear Information System (INIS)

    Food technology and food processing techniques have made tremendous advances in preservation of food and ensuring safety of food by killing food-borne pathogens. In addition to old techniques such as pasteurization, canning, dehydration, fermentation and salting, a number of new techniques such as radiation processing, high pressure technology and pulsed electric field technology are being applied for preservation of food and to ensure food safety. Total Quality Management (TQM) concepts have been developed to take care of food safety from farm to table. Hazard Analysis at Critical Control Points (HACCP) is being applied for mass scale production of food to make food free from pathogens. Despite these advances, food-borne diseases have become one of the most widespread public health problems in the world. About two thirds of all the outbreaks are traced to microbial contaminated food. According to World Health Organization (WHO) estimates, food-borne and waterborne diarrhoeal diseases kill an estimated 2 million people annually, including many children. Food safety is a major concern not only for developing countries but also for the developed countries. A number of factors such as emergence of new food-borne pathogens, development of drug resistance in pathogens, changing life style, globalization of the food supply etc. are responsible for the continuous persistence of food-borne diseases. The food-borne disease outbreaks due to E. coli O157:H7, Listeria monocytogenes, Salmonella and Campylobacter, are responsible for recall of many foods resulting in heavy losses to food industry. Due to consumer demand, a number of Ready-To-Eat (RTE) minimally processed foods are increasingly marketed; however, there is increased risk of foodborne diseases with these products. Food Technology Division of Bhabha Atomic Research Centre, Mumbai, has been working on food-borne bacterial pathogens particularly Salmonella, Campylobacter, Listeria monocytogenes, Vibrio and Aeromonasf

  16. Personality in Adults Who Were Born Very Preterm.

    Directory of Open Access Journals (Sweden)

    Christin L Hertz

    Full Text Available To investigate the personality in very preterm individuals (VPT; gestational age, GA, <32 weeks at adult age in two cohorts born in 1974-76 and 1980-82, respectively, and to illuminate the effect of increased survival rates and the clinical implications of deviations in personality.Demographic data were extracted for all individuals born in Denmark in 1974-76 and 1980-82. From each period one index-group each comprising 150 individuals with the lowest gestational age was selected. Thereafter two control groups born at term were matched by gender, age and residential area. Personality was assessed with the short version of NEO PI-R, and psychiatric diagnoses were obtained from the Danish Psychiatric Central Research Register.Of all the individuals born <32 weeks of gestation in 1980-82 67% were alive in 2006 vs. 43% of those born in 1974-76 (p<0.0001. A total of 433 individuals participated in the study, 76% of the VPT groups (n = 227, mean GA = 27.9 and 69% of the control groups (n = 206. There were no significant differences on personality scores between the two VPT groups. Compared to the control groups, the combined VPT groups scored higher on neuroticism (p = 0.005 and agreeableness (p = 0.012, but lower on extraversion (p = 0.002. Psychiatric disorder was strongly associated with higher scores on neuroticism and lower scores on extraversion.Improved survival of VPT infants was not associated with increased deviances in the personality as adults. The personality traits in VPT individuals differ moderately from those of term born controls. High scores in neuroticism and low scores in extraversion were associated with increased risk psychiatric disorders. VPT adults also showed signs of positive adaptation in the form of an agreeable and confident attitude towards others.The much improved survival rate in very preterm infants during the early years of active neonatology was not associated with increased risk of

  17. The Near Zone to Far Zone Transformation (N2F)

    Energy Technology Data Exchange (ETDEWEB)

    Blackfield, Donald T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Poole, Brian R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-03-11

    N2F is a C/C++ code used to calculate the far zone electromagnetic (EM) field, given E and H near zone field data. The method used by N2F can be found in Ref. 1 and 2. N2F determines the far field EΦ and Eθ in spherical coordinates for near zone data calculated in either Cartesian or Cylindrical geometry.

  18. Empowerment Zones and Enterprise Districts - Volusia County Enterprise Zones

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Florida's Enterprise Zone Program encourages economic growth and investment in distressed areas by offering tax advantages and incentives to businesses that are...

  19. Tick-borne encephalitis virus infection in humans

    Directory of Open Access Journals (Sweden)

    Hrnjaković-Cvjetković Ivana

    2016-01-01

    Full Text Available Introduction. Tick-borne meningoencephalitis virus is a flavivirus that causes the most important vector-borne central nervous system infection in many countries of Europe and Asia. There are three subtypes of tick-borne encephalitis virus: European, Siberian and the Far-Eastern subtype. Transmission. In endemic areas, the virus remains in transmissive cycles between Ixodes ticks and small rodents. Clinical picture. In most cases (70−98% infection goes asymptomatically. In about one-third of meningitis cases, meningoencephalitis or meningomyelitis is developed. Postencephalytic syndrome may be the complication of the infection, presenting with neurological symptoms. Diagnosis. Etiologic diagnosis of tick-borne meningoencephalitis is only made on basis of laboratory analyses. Reverse transcription-polymerase chain reaction is used for determining the presence of virus in the blood and cerebrospinal fluid. Antibodies in blood and cerebrospinal fluid can be detected by serological tests. Prevention. The most efficient way to control this potentially severe disease with possible serious long-term consequences is vaccination. It should be recommended to persons who live or travel to endemic areas. Conclusion. In Serbia, tick-borne encephalitis virus infection belongs to the list of reportable diseases; however, there are no reported cases because the diagnostics is not performed routinely. We believe that the significance of this zoonosis must be examined in our country and some of its parts because of preliminary positive serological findings found out in Vojvodina as well as because of reported cases in neighboring countries such as Hungary and Croatia and its worldwide distribution.

  20. DNA microarray technique for detecting food-borne pathogens

    Directory of Open Access Journals (Sweden)

    Xing GAO

    2012-08-01

    Full Text Available Objective To study the application of DNA microarray technique for screening and identifying multiple food-borne pathogens. Methods The oligonucleotide probes were designed by Clustal X and Oligo 6.0 at the conserved regions of specific genes of multiple food-borne pathogens, and then were validated by bioinformatic analyses. The 5' end of each probe was modified by amino-group and 10 Poly-T, and the optimized probes were synthesized and spotted on aldehyde-coated slides. The bacteria DNA template incubated with Klenow enzyme was amplified by arbitrarily primed PCR, and PCR products incorporated into Aminoallyl-dUTP were coupled with fluorescent dye. After hybridization of the purified PCR products with DNA microarray, the hybridization image and fluorescence intensity analysis was acquired by ScanArray and GenePix Pro 5.1 software. A series of detection conditions such as arbitrarily primed PCR and microarray hybridization were optimized. The specificity of this approach was evaluated by 16 different bacteria DNA, and the sensitivity and reproducibility were verified by 4 food-borne pathogens DNA. The samples of multiple bacteria DNA and simulated water samples of Shigella dysenteriae were detected. Results Nine different food-borne bacteria were successfully discriminated under the same condition. The sensitivity of genomic DNA was 102 -103pg/ μl, and the coefficient of variation (CV of the reproducibility of assay was less than 15%. The corresponding specific hybridization maps of the multiple bacteria DNA samples were obtained, and the detection limit of simulated water sample of Shigella dysenteriae was 3.54×105cfu/ml. Conclusions The DNA microarray detection system based on arbitrarily primed PCR can be employed for effective detection of multiple food-borne pathogens, and this assay may offer a new method for high-throughput platform for detecting bacteria.

  1. Nairu en zone heureuse

    OpenAIRE

    Reynès, Frédéric; Lemoine, Matthieu; Veroni, Paola

    2007-01-01

    Cette étude spéciale propose des estimations du niveau non inflationniste du taux de chômage (Nairu) pour la zone euro agrégée, pour la France, l’Italie et l’Allemagne. Une équation d’inflation, qui dépend de l’écart du taux de chômage au Nairu, est estimée par le filtre de Kalman. Le modèle le plus simple, qui considère le Nairu comme une marche aléatoire, a des capacités prédictives limitées. Il diagnostique un taux de chômage inférieur au Nairu à l’horizon de notre prévision. Il est con...

  2. Saturated Zone Colloid Transport

    Energy Technology Data Exchange (ETDEWEB)

    H. S. Viswanathan

    2004-10-07

    This scientific analysis provides retardation factors for colloids transporting in the saturated zone (SZ) and the unsaturated zone (UZ). These retardation factors represent the reversible chemical and physical filtration of colloids in the SZ. The value of the colloid retardation factor, R{sub col} is dependent on several factors, such as colloid size, colloid type, and geochemical conditions (e.g., pH, Eh, and ionic strength). These factors are folded into the distributions of R{sub col} that have been developed from field and experimental data collected under varying geochemical conditions with different colloid types and sizes. Attachment rate constants, k{sub att}, and detachment rate constants, k{sub det}, of colloids to the fracture surface have been measured for the fractured volcanics, and separate R{sub col} uncertainty distributions have been developed for attachment and detachment to clastic material and mineral grains in the alluvium. Radionuclides such as plutonium and americium sorb mostly (90 to 99 percent) irreversibly to colloids (BSC 2004 [DIRS 170025], Section 6.3.3.2). The colloid retardation factors developed in this analysis are needed to simulate the transport of radionuclides that are irreversibly sorbed onto colloids; this transport is discussed in the model report ''Site-Scale Saturated Zone Transport'' (BSC 2004 [DIRS 170036]). Although it is not exclusive to any particular radionuclide release scenario, this scientific analysis especially addresses those scenarios pertaining to evidence from waste-degradation experiments, which indicate that plutonium and americium may be irreversibly attached to colloids for the time scales of interest. A section of this report will also discuss the validity of using microspheres as analogs to colloids in some of the lab and field experiments used to obtain the colloid retardation factors. In addition, a small fraction of colloids travels with the groundwater without any significant

  3. The zone of alienation

    International Nuclear Information System (INIS)

    Ten years after the nuclear disaster, people still live and die in Chernobyl. Thousands of people continue to live and work there. Roughly 500 have moved back into their old homes inside the alienation zone. Fewer than half still alive. Medical researchers in the area insist that immune systems are weakened by doses of radiation far lower than previously thought. However, an European Union sponsored study concluded that Chernobyl's toll has been exaggerated. Thus, while 760 children in the contaminated area have developed thyroid cancer, only three have died as a result. Yet in and around Chernobyl, people carry on their lives and the Ukrainian Government says it can't afford to close the plant without billions of dollars in Western aid. ills

  4. Contaminants in Vadose Zone Environments

    Energy Technology Data Exchange (ETDEWEB)

    Wellman, Dawn M.; Freshley, Mark D.; Johnson, Timothy C.; Miracle, Ann L.

    2012-11-01

    Contaminants in vadose zone environments pose a long-term source and threat to groundwater resources, human health, and the environment. Several technical, regulatory, and policy challenges and opportunities are associated with contamination in vadose zone environments, particularly in remediation. In this special issue, ten papers present novel approaches to characterize, monitor, remediate, and predict the transport and fate of contaminants in vadose zone environments.

  5. Street Prostitution Zones and Crime

    OpenAIRE

    Bisschop, Paul; Kastoryano, Stephen; Van der Klaauw, Bas

    2015-01-01

    This paper studies the effects of introducing legal street prostitution zones on both registered and perceived crime. We exploit a unique setting in the Netherlands where legal street prostitution zones were opened in nine cities under different regulation systems. We provide evidence that the opening of these zones was not in response to changes in crime. Our difference-in-difference analysis using data on the largest 25 Dutch cities between 1994 and 2011 shows that opening a legal street pr...

  6. Learning About Intervention Target Zones

    OpenAIRE

    Klein, Michael W; Karen K. Lewis

    1991-01-01

    This paper provides a framework for evaluating how market participants' beliefs about foreign exchange target zones change as they learn about central bank intervention policy. In order to examine this behavior, we first generalize the standard target zone model to allow for intra-marginal intervention. Intra-marginal intervention implies that the position of market participants' beliefs about the target zone can be determined from their beliefs about the likelihood of intervention. As an app...

  7. Race, Ethnicity, and Discriminatory Zoning

    OpenAIRE

    Allison Shertzer; Tate Twinam; Randall P. Walsh

    2014-01-01

    Zoning has been cited as a discriminatory policy tool by critics, who argue that ordinances are used to deter the entry of minority residents into majority neighborhoods through density restrictions (exclusionary zoning) and locate manufacturing activity in minority neighborhoods (environmental racism). However, identifying discrimination in these regulations is complicated by the fact that land use and zoning have been co-evolving for nearly a century in most American cities, rendering resid...

  8. Problems of Chernobyl Exclusion Zone

    International Nuclear Information System (INIS)

    The collection comprises the results of researches and design activity in the ChNPP exclusion zone, aimed at the development of technologies, equipment and devices for radioactive waste management and ChNPP accident clean-up, at studying the composition and structure of the Exclusion zone soil activity solid bearers, form transformation of the fission products of fuel fallout radionuclide composition in the ChNPP near zone, the spatial distribution of radionuclides and other radioecological issues.. Much attention is paid to medical and biological aspects of the accident influence on the flora, fauna and people's health, labour conditions and incidence of the workers of the Exclusion zone

  9. International Network for Capacity Building for the Control of Emerging Viral Vector-Borne Zoonotic Diseases: Arbo-Zoonet

    NARCIS (Netherlands)

    Ahmed, J.; Bouloy, M.; Ergonul, O.; Fooks, A.R.; Paweska, J.; Chevalier, V.; Drosten, C.; Moormann, R.J.M.; Tordo, N.; Vatansever, Z.; Calistri, P.; Estrada-Pena, A.; Mirazimi, A.; Unger, H.; Yin, H.; Seitzer, U.

    2009-01-01

    Arboviruses are arthropod-borne viruses, which include West Nile fever virus (WNFV), a mosquito-borne virus, Rift Valley fever virus (RVFV), a mosquito-borne virus, and Crimean-Congo haemorrhagic fever virus (CCHFV), a tick-borne virus. These arthropod-borne viruses can cause disease in different do

  10. Block the Buzzing, Bites, and Bumps: Preventing Mosquito-Borne Illnesses

    Science.gov (United States)

    ... Subscribe Block the Buzzing, Bites, and Bumps Preventing Mosquito-Borne Illnesses Summer can be a bummer if ... find better ways to diagnose, treat, and prevent mosquito-borne illnesses. And we can all take simple ...

  11. Pan-European Chikungunya surveillance: designing risk stratified surveillance zones.

    Science.gov (United States)

    Tilston, Natasha; Skelly, Chris; Weinstein, Phil

    2009-01-01

    The first documented transmission of Chikungunya within Europe took place in Italy during the summer of 2007. Chikungunya, a viral infection affecting millions of people across Africa and Asia, can be debilitating and no prophylactic treatment exists. Although imported cases are reported frequently across Europe, 2007 was the first confirmed European outbreak and available evidence suggests that Aedes albopictus was the vector responsible and the index case was a visitor from India. This paper proposed pan-European surveillance zones for Chikungunya, based on the climatic conditions necessary for vector activity and viral transmission. Pan-European surveillance provides the best hope for an early-warning of outbreaks, because national boundaries do not play a role in defining the risk of this new vector borne disease threat. A review of climates, where Chikungunya has been active, was used to inform the delineation of three pan-European surveillance zones. These vary in size each month across the June-September period of greatest risk. The zones stretch across southern Europe from Portugal to Turkey. Although the focus of this study was to define the geography of potential surveillance zones based on the climatic limits on the vector and virus, a preliminary examination of inward bound airline passengers was also undertaken. This indicated that France and Italy are likely to be at greater risk due to the number of visitors they receive from Chikungunya active regions, principally viraemic visitors from India. Therefore this study represents a first attempt at creating risk stratified surveillance zones, which we believe could be usefully refined with the use of higher resolution climate data and more complete air travel data. PMID:19878588

  12. Pan-European Chikungunya surveillance: designing risk stratified surveillance zones

    Directory of Open Access Journals (Sweden)

    Skelly Chris

    2009-10-01

    Full Text Available Abstract The first documented transmission of Chikungunya within Europe took place in Italy during the summer of 2007. Chikungunya, a viral infection affecting millions of people across Africa and Asia, can be debilitating and no prophylactic treatment exists. Although imported cases are reported frequently across Europe, 2007 was the first confirmed European outbreak and available evidence suggests that Aedes albopictus was the vector responsible and the index case was a visitor from India. This paper proposed pan-European surveillance zones for Chikungunya, based on the climatic conditions necessary for vector activity and viral transmission. Pan-European surveillance provides the best hope for an early-warning of outbreaks, because national boundaries do not play a role in defining the risk of this new vector borne disease threat. A review of climates, where Chikungunya has been active, was used to inform the delineation of three pan-European surveillance zones. These vary in size each month across the June-September period of greatest risk. The zones stretch across southern Europe from Portugal to Turkey. Although the focus of this study was to define the geography of potential surveillance zones based on the climatic limits on the vector and virus, a preliminary examination of inward bound airline passengers was also undertaken. This indicated that France and Italy are likely to be at greater risk due to the number of visitors they receive from Chikungunya active regions, principally viraemic visitors from India. Therefore this study represents a first attempt at creating risk stratified surveillance zones, which we believe could be usefully refined with the use of higher resolution climate data and more complete air travel data.

  13. SIGNR1-Negative Red Pulp Macrophages Protect against Acute Streptococcal Sepsis after Leishmania donovani-Induced Loss of Marginal Zone Macrophages

    OpenAIRE

    Kirby, Alun C.; Beattie, Lynette; Maroof, Asher; van Rooijen, Nico; Kaye, Paul M.

    2009-01-01

    Marginal zone macrophages in the murine spleen play an important role in the capture of blood-borne pathogens and are viewed as an essential component of host defense against the development of pneumococcal sepsis. However, we and others have previously described the loss of marginal zone macrophages associated with the splenomegaly that follows a variety of viral and protozoal infections; this finding raises the question of whether these infected mice would become more susceptible to seconda...

  14. The what, why, and how of born-open data.

    Science.gov (United States)

    Rouder, Jeffrey N

    2016-09-01

    Although many researchers agree that scientific data should be open to scrutiny to ferret out poor analyses and outright fraud, most raw data sets are not available on demand. There are many reasons researchers do not open their data, and one is technical. It is often time consuming to prepare and archive data. In response, my laboratory has automated the process such that our data are archived the night they are created without any human approval or action. All data are versioned, logged, time stamped, and uploaded including aborted runs and data from pilot subjects. The archive is GitHub, github.com, the world's largest collection of open-source materials. Data archived in this manner are called born open. In this paper, I discuss the benefits of born-open data and provide a brief technical overview of the process. I also address some of the common concerns about opening data before publication.

  15. Coulomb-Born-Oppenheimer approximation in Ps-H scattering

    Indian Academy of Sciences (India)

    Hasi Ray

    2006-02-01

    To improve the Coulomb-Born approximation (CBA) theory of ionization in positronium (Ps) and atom scattering, the effect of exchange is introduced. The nine-dimensional exchange amplitude for ionization of Ps in Ps-H scattering is reduced to a two-dimensional integral using the present Coulomb-Born-Oppenheimer approximation (CBOA). The methodology is extremely useful to evaluate ionization parameters for different target systems and for different types of ionization processes. It is then applied to evaluate the Ps-ionization cross-section and to estimate the effect of exchange on Ps-ionization in Ps-H system. We establish the importance of exchange at lower energy region.

  16. Electronic Flux Density beyond the Born-Oppenheimer Approximation.

    Science.gov (United States)

    Schild, Axel; Agostini, Federica; Gross, E K U

    2016-05-19

    In the Born-Oppenheimer approximation, the electronic wave function is typically real-valued and hence the electronic flux density (current density) seems to vanish. This is unfortunate for chemistry, because it precludes the possibility to monitor the electronic motion associated with the nuclear motion during chemical rearrangements from a Born-Oppenheimer simulation of the process. We study an electronic flux density obtained from a correction to the electronic wave function. This correction is derived via nuclear velocity perturbation theory applied in the framework of the exact factorization of electrons and nuclei. To compute the correction, only the ground state potential energy surface and the electronic wave function are needed. For a model system, we demonstrate that this electronic flux density approximates the true one very well, for coherent tunneling dynamics as well as for over-the-barrier scattering, and already for mass ratios between electrons and nuclei that are much larger than the true mass ratios.

  17. Rationale for wind-borne missile criteria for DOE facilities

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, J R; Murray, R

    1999-09-01

    High winds tend to pick up and transport various objects and debris, which are referred to as wind-borne missiles or tornado missiles, depending on the type of storm. Missiles cause damage by perforating the building envelope or by collapsing structural elements such as walls, columns or frames. The primary objectives of this study are as follows: (1) to provide a basis for wind-borne or tornado missile criteria for the design and evaluation of DOE facilities, and (2) to provide guidelines for the design and evaluation of impact-resistant missile barriers for DOE facilities The first objective is accomplished through a synthesis of information from windstorm damage documentation experience and computer simulation of missile trajectories. The second objective is accomplished by reviewing the literature, which describes various missile impact tests, and by conducting a series of impact tests at a Texas Tech University facility to fill in missing information.

  18. Topological vortices in generalized Born-Infeld-Higgs electrodynamics

    Science.gov (United States)

    Casana, R.; Hora, E. da; Rubiera-Garcia, D.; Santos, C. dos

    2015-08-01

    A consistent BPS formalism to study the existence of topological axially symmetric vortices in generalized versions of the Born-Infeld-Higgs electrodynamics is implemented. Such a generalization modifies the field dynamics via the introduction of three nonnegative functions depending only in the Higgs field, namely, , , and . A set of first-order differential equations is attained when these functions satisfy a constraint related to the Ampère law. Such a constraint allows one to minimize the system's energy in such way that it becomes proportional to the magnetic flux. Our results provides an enhancement of the role of topological vortex solutions in Born-Infeld-Higgs electrodynamics. Finally, we analyze a set of models entailing the recovery of a generalized version of Maxwell-Higgs electrodynamics in a certain limit of the theory.

  19. Topological vortices in generalized Born-Infeld-Higgs electrodynamics

    CERN Document Server

    Casana, R; Rubiera-Garcia, D; Santos, C dos

    2015-01-01

    A consistent BPS formalism to study the existence of topological axially symmetric vortices in generalized versions of the Born-Infeld-Higgs electrodynamics is implemented. Such a generalization modifies the field dynamics via introduction of three non-negative functions depending only in the Higgs field, namely, $G(|\\phi|)$, $w(|\\phi|) $ and $V(|\\phi|)$. A set of first-order differential equations is attained when these functions satisfy a constraint related to the Ampere law. Such a constraint allows to minimize the system energy in such way that it becomes proportional to the magnetic flux. Our results provides an enhancement of topological vortex solutions in Born-Infeld-Higgs electrodynamics. Finally, we analyze a set of models such that a generalized version of Maxwell-Higgs electrodynamics is recovered in a certain limit of the theory.

  20. Topological vortices in generalized Born-Infeld-Higgs electrodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Casana, R. [Universidade Federal do Maranhao, Departamento de Fisica, Sao Luis, Maranhao (Brazil); Hora, E. da [Universidade Federal do Maranhao, Departamento de Fisica, Sao Luis, Maranhao (Brazil); Universidade Federal do Maranhao, Coordenadoria Interdisciplinar de Ciencia e Tecnologia, Sao Luis, Maranhao (Brazil); Rubiera-Garcia, D. [Fudan University, Department of Physics, Center for Field Theory and Particle Physics, Shanghai (China); Santos, C. dos [Faculdade de Ciencias da Universidade do Porto, Centro de Fisica e Departamento de Fisica e Astronomia, Porto (Portugal)

    2015-08-15

    A consistent BPS formalism to study the existence of topological axially symmetric vortices in generalized versions of the Born-Infeld-Higgs electrodynamics is implemented. Such a generalization modifies the field dynamics via the introduction of three nonnegative functions depending only in the Higgs field, namely,G(vertical stroke φ vertical stroke), w(vertical stroke φ vertical stroke), and V (vertical stroke φ vertical stroke). A set of first-order differential equations is attained when these functions satisfy a constraint related to the Ampere law. Such a constraint allows one to minimize the system's energy in such way that it becomes proportional to the magnetic flux. Our results provides an enhancement of the role of topological vortex solutions in Born-Infeld-Higgs electrodynamics. Finally, we analyze a set of models entailing the recovery of a generalized version of Maxwell-Higgs electrodynamics in a certain limit of the theory. (orig.)

  1. Born-Infeld electrodynamics in very special relativity

    CERN Document Server

    Bufalo, R

    2015-01-01

    In this work we discuss the properties of a modified Born-Infeld electrodynamics in the framework of very special relativity (VSR). This proposal allows us to study VSR mass effects in a gauge-invariant context of nonlinear electrodynamics. It is analyzed in detail the electrostatic solutions for two different cases, as well as the VSR dispersion relations are found to be of a \\emph{massive} particle with nonlinear modifications. Afterwards, the field energy and static potential are computed, in the latter we find from the VSR contribution a novel long-range $1/L^3$ correction to the Coulomb potential, in contrast to the $1/L^5$ correction of the usual Born-Infeld theory.

  2. Zone refining of plutonium metal

    International Nuclear Information System (INIS)

    The zone refining process was applied to Pu metal containing known amounts of impurities. Rod specimens of plutonium metal were melted into and contained in tantalum boats, each of which was passed horizontally through a three-turn, high-frequency coil in such a manner as to cause a narrow molten zone to pass through the Pu metal rod 10 times. The impurity elements Co, Cr, Fe, Ni, Np, U were found to move in the same direction as the molten zone as predicted by binary phase diagrams. The elements Al, Am, and Ga moved in the opposite direction of the molten zone as predicted by binary phase diagrams. As the impurity alloy was zone refined, δ-phase plutonium metal crystals were produced. The first few zone refining passes were more effective than each later pass because an oxide layer formed on the rod surface. There was no clear evidence of better impurity movement at the slower zone refining speed. Also, constant or variable coil power appeared to have no effect on impurity movement during a single run (10 passes). This experiment was the first step to developing a zone refining process for plutonium metal

  3. Instrumentation for coastal zone management

    Digital Repository Service at National Institute of Oceanography (India)

    Joseph, A.

    stream_size 11 stream_content_type text/plain stream_name Trg_Course_Coast_Zone_Manage_1993_91.pdf.txt stream_source_info Trg_Course_Coast_Zone_Manage_1993_91.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset...

  4. Management of coastal zone vegetation

    Digital Repository Service at National Institute of Oceanography (India)

    Untawale, A.G.

    stream_size 14 stream_content_type text/plain stream_name Trg_Course_Coast_Zone_Manage_1993_22.pdf.txt stream_source_info Trg_Course_Coast_Zone_Manage_1993_22.pdf.txt Content-Encoding ISO-8859-1 Content-Type text/plain; charset...

  5. Excavation damaged zone

    Energy Technology Data Exchange (ETDEWEB)

    Popp, T.; Salzer, K.; Minkley, W. [Institut fur Gebirgsmechanik GmbH, Leipzig (Germany); Gibert, D.; Nicollin, F.; Kergosien, B. [Rennes-1 Univ., GdR FORPRO (CNRS/ANDRA GdR 788) and Geosciences Rennes (CNRS/UR1 UMR 6118) (France); Bossart, P. [Federal Office for Topography, Wabern (Switzerland); Nussbaum, C. [Institut Geotechnique SA, St-Ursanne (Switzerland); Robinet, J.C.; Nguyen, M.T. [EGC Euro-Geomat-Consulting, 45 - Orleans (France); Barnichon, J.D.; Plas, F. [ANDRA - Agence Nationale pour la Gestion des Dechets Radioactifs, 92 - Chatenay Malabry (France); Ghorbani, A.; Cosenza, P.; Florsch, N. [Pierre et Marie Curie Univ., UMR 7619 Sisyphe, 75 - Paris (France); Revil, A.; Jougnot, D. [Aix-Marseille-2, UMR 6635, CNRS-CEREGE, 13 (France); Schmutz, M. [EGID, M. de Montaigne Univ., 33 - Pessac (France); Contrucci, I.; Klein, E. [Institut National de l' Environnement Industriel et des Risques (INERIS), Ecole des Mines de Nancy, 54 - Nancy (France); Cabrera, J.; Ben-Slimane, K.; Rejeb, A.; Matray, J.M.; Savoye, S. [Institut de Radioprotection et de Surete Nucleaire (IRSN), 92 - Fontenay-aux-Roses (France); Maiolino, S. [Ecole Polytechnique, Lab. de Mecanique des Solides, UMR 7649, LMS, 91 - Palaiseau (France); CETE de Lyon/LRPC de Lyon/Meca Roches/ ERA, 69 - Bron (France); Yong, S.; Loew, S.; Fidelibus, C.; Lemy, F. [Engineering Geology, ETH Zurich, Zurich (Switzerland); Frank, E. [Swiss Federal Nuclear Safety Inspectorate (HSK), Villigen (Switzerland); Chun-Liang, Zhang; Tilmann, Rothfuchs [Gesellschaft fur Anlagen- und Reaktorsicherheit (GRS) mbH, Braunschweig (Germany)

    2007-07-01

    This session gathers 10 articles (posters) dealing with: the influence of bedding planes to EDZ evolution and the coupled HM properties of Opalinus Clay; the electrical tomography monitoring of the EDZ during the excavation of the gallery 04 in the Mont Terri rock laboratory; the seismic endoscopy and tomography of the EDZ of the gallery 04 in the Mont Terri rock laboratory; a elastoplastic damage model for saturated and unsaturated stiffness clays: description and application to the modelling of EDZ around drifts in Callovo-Oxfordian argillites; the non-invasive monitoring of water content and microcracks in argillites using spectral induced polarization; EDZ investigations by ultrasonic borehole logging in drifts of different ages excavated in argillaceous formations of the Tournemire experimental station (Aveyron, France); the excavation damaged zones in the argillaceous Tournemire site: characterisation and failure mechanisms; the hardening-based degradation factor: influence of mean stress and stiffness; the disturbance in the EDZ in the Opalinus clay at Mont Terri; and the experimental study on self-sealing capacity of clay rocks.

  6. Volcanic Zone, New Zealand

    Directory of Open Access Journals (Sweden)

    Graham J. Weir

    2001-01-01

    Full Text Available A conceptual model of the Taupo Volcanic Zone (TVZ is developed, to a depth of 25 km, formed from three constant density layers. The upper layer is formed from eruption products. A constant rate of eruption is assumed, which eventually implies a constant rate of extension, and a constant rate of volumetric creation in the middle and bottom layers. Tectonic extension creates volume which can accomodate magmatic intrusions. Spreading models assume this volume is distributed throughout the whole region, perhaps in vertical dykes, whereas rifting models assume the upper crust is thinned and the volume created lies under this upper crust. Bounds on the heat flow from such magmatic intrusions are calculated. Heat flow calculations are performed and some examples are provided which match the present total heat output from the TVZ of about 4200 MW, but these either have extension rates greater than the low values of about 8 ± 4 mm/a being reported from GPS measurements, or else consider extension rates in the TVZ to have varied over time.

  7. Cosmological constraints for an Eddington-Born-Infeld field

    CERN Document Server

    De Felice, Antonio; Jhingan, Sanjay

    2012-01-01

    We consider the Eddington-Born-Infeld (EBI) model here without assuming any cosmological constant. The EBI scalar field is supposed to play a role of both dark matter and dark energy. Different eras in cosmology are reconstructed for the model. A comparison is drawn with $\\Lambda$CDM model using Supernova Ia, WMAP7 and BAO data. It seems that the EBI field in this form does not give good fit to observational data in comparison to the $\\Lambda$CDM model.

  8. Global Change and Human Vulnerability to Vector-Borne Diseases

    OpenAIRE

    Sutherst, Robert W.

    2004-01-01

    Global change includes climate change and climate variability, land use, water storage and irrigation, human population growth and urbanization, trade and travel, and chemical pollution. Impacts on vector-borne diseases, including malaria, dengue fever, infections by other arboviruses, schistosomiasis, trypanosomiasis, onchocerciasis, and leishmaniasis are reviewed. While climate change is global in nature and poses unknown future risks to humans and natural ecosystems, other local changes ar...

  9. Prevalence of vector-borne pathogens in dogs from Haiti.

    Science.gov (United States)

    Starkey, Lindsay A; Newton, Kassie; Brunker, Jill; Crowdis, Kelly; Edourad, Emile Jean Pierre; Meneus, Pedro; Little, Susan E

    2016-07-15

    Canine vector-borne pathogens are common on some Caribbean islands, but survey data in Haiti are lacking. To determine the prevalence of selected vector-borne pathogens in dogs from Haiti, we tested blood samples collected from 210 owned dogs, 28 (13.3%) of which were infested with Rhipicephalus sanguineus ticks at the time of blood collection. No other tick species were identified on these dogs. A commercially available ELISA identified antibodies to Ehrlichia spp. in 69 (32.9%), antibodies to Anaplasma spp. in 37 (17.6%), and antigen of Dirofilaria immitis in 55 (26.2%); antibodies to Borrelia burgdorferi were not detected in any sample. Molecular assays of whole blood from 207 of the dogs confirmed infection with Ehrlichia canis (15; 7.2%), Anaplasma platys (13; 6.3%), D. immitis (46; 22.2%), Wolbachia spp. (45; 21.7%), Babesia vogeli (16; 7.7%), and Hepatozoon canis (40; 19.3%), but Anaplasma phagocytophilum, Babesia canis, Babesia rossi, Babesia gibsoni, Ehrlichia chaffeensis, Ehrlichia ewingii, or Hepatozoon americanum were not detected. Co-infection with two or more vector-borne pathogens was detected by serology in 42 (20.0%) dogs and by molecular assays in 22 (10.6%) dogs; one dog was co-infected with B. vogeli and E. canis as detected by PCR with D. immitis detected by serology (antigen). Overall, evidence of past or current infection with at least one vector-borne pathogen was identified in 142/210 (67.6%) dogs in this study, underscoring the common nature of these pathogens, some of which are zoonotic, in Haiti. PMID:27270383

  10. Food-borne bacteremic illnesses in febrile neutropenic children

    OpenAIRE

    Anselm Chi-wai Lee; Nellie Dawn Siao-ping Ong

    2011-01-01

    Bacteremia following febrile neutropenia is a serious complication in children with malignancies. Preventive measures are currently targeted at antimicrobial prophylaxis, amelioration of drug-induced neutropenia, and nosocomial spread of pathogens, with little attention to community-acquired infections. A retrospective study was conducted at a pediatric oncology center during a 3-year period to identify probable cases of food-borne infections with bacteremia. Twenty-one bacteremic illnesses a...

  11. Pure spinor superfields and Born-Infeld theory

    CERN Document Server

    Cederwall, Martin

    2011-01-01

    We present a method for introducing and analysing higher-derivative deformations of maximally supersymmetric field theories. Such terms are built in the pure spinor superfield framework, using a set of operators representing physical fields. The action for abelian Born-Infeld theory becomes polynomial in this language, and contains only a four-point interaction in addition to the free action. Simplifications also occur in the non-abelian case.

  12. Epidemiology of tick-borne borreliosis in Morocco

    OpenAIRE

    Diatta, Georges; Souidi, Yassine; Granjon, Laurent; Arnathau, Céline; Durand, Patrick; Chauvancy, Gilles; Mané, Youssouph; Sarih, M'Hammed; BELGHYTI, Driss; Renaud, François; Trape, Jean-François

    2012-01-01

    Background: The presence in Morocco of Argasid ticks of the Ornithodoros erraticus complex, the vector of tick-borne relapsing fever (TBRF) in North Africa, has been known since 1919, but the disease is rarely diagnosed and few epidemiological data are available. Methodology/Principal Findings: Between 2006 and 2011, we investigated the presence of Ornithodoros ticks in rodent burrows in 34 sites distributed across Morocco. We also collected small mammals in 10 sites and we investigated TBRF ...

  13. Weyl invariant Dirac-Born-Infeld-Einstein theory

    CERN Document Server

    Kan, Nahomi; Shiraishi, Kiyoshi

    2010-01-01

    We consider a Weyl invariant extension of Dirac-Born-Infeld type gravity. An appropriate choice of the metric hides the scalar degree of freedom which is required by the local scale invariance of the action at the first sight, and then a vector field acquires mass. Moreover, nonminimal couplings of the vector field and curvatures are induced, which may be suitable to the vector inflation scenario.

  14. Memory Processes in Learning Disability Subtypes of Children Born Preterm

    OpenAIRE

    McCoy, Thomasin E; Conrad, Amy L.; Richman, Lynn C.; Nopoulos, Peg C.; Bell, Edward F.

    2012-01-01

    The purpose of this study was to evaluate immediate auditory and visual memory processes in learning disability subtypes of 40 children born preterm. Three subgroups of children were examined: (a) primary language disability group (n = 13), (b) perceptual-motor disability group (n = 14), and (c) no learning disability diagnosis group without identified language or perceptual-motor learning disability (n = 13). Between-group comparisons indicate no significant differences in immediate auditory...

  15. Born Global Sourcers – buying internationally right from the inception

    DEFF Research Database (Denmark)

    Rask, Morten; Servais, Per

    time researchers has identified various types of INV’s and based on the empirical work by Rasmussen et al (2010) a particular type of international new venture is isolated. The Born Global sourcers which is firms who conducts international purchasing from or near their establishment but who only...... be a viable starting point for research into this type, but that this research could be supplemented by including the relations to domestic clients/partners....

  16. Majorana Fermions, Supersymmetry Breaking, and Born-Infeld Theory

    CERN Document Server

    Ferrara, Sergio; Yeranyan, Armen

    2015-01-01

    This review is devoted to highlight some aspects of the relevance of Majorana fermions in rigid supersymmetry breaking in four spacetime dimensions. After introducing some basic facts on spinors, and on their symmetries and reality properties, we consider Goldstino actions describing partial breaking of rigid supersymmetry, then focussing on Born-Infeld non-linear theory, its duality symmetry, and its supersymmetric extensions, also including multi-field generalizations exhibiting doubly self-duality.

  17. The virial theorem in Eddington-Born-Infeld gravity

    OpenAIRE

    Santos, Noelia S.; Santos, Janilo

    2015-01-01

    We consider the possibility that the Eddington-Born-Infeld (EBI) modified gravity provides an alternative explanation for the mass discrepancy in clusters of galaxies. For this purpose we derive the modified Einstein field equations, finding an additional "geometrical mass" term which provides an effective contribution to the gravitational binding energy. Using some approximations and assumptions for weak gravitational fields, and taking into account the collisionless relativistic Boltzmann e...

  18. Approaches towards tick and tick-borne diseases control

    OpenAIRE

    Ana Domingos; Sandra Antunes; Lara Borges; Virgilio Estolio do Rosario

    2013-01-01

    Ticks are obligate haematophagous ectoparasites of wild and domestic animals as well as humans, considered to be second worldwide to mosquitoes as vectors of human diseases. Tick-borne diseases are responsible worldwide for great economic losses in terms of mortality and morbidity of livestock animals. This review concerns to the different tick and tick-parasites control methods having a major focus on vaccines. Control of tick infestations has been mainly based on the use of acaricides, a co...

  19. Air-borne contact dermatitis caused exclusively by xanthium strumarium

    OpenAIRE

    Pasricha J; Verma Kaushal; D′Souza Pascal

    1995-01-01

    Most cases having air-borne contact dermatitis (ABCD) in India are considered to be caused by Parthenium hysterophorus. In some cases however, other plants have also been noticed to give positive patch test reactions. We are reporting two cases presenting as ABCD who showed positive patch tests with Xanthium strumarium while the patch tests with Parthenium hysterophorus were negative. It is therefore necessary to realise that every case of ABCD is not caused by Parthenium, and patch testing w...

  20. Feed-borne transmission and case clustering of BSE.

    OpenAIRE

    Hagenaars, T J; Ferguson, N. M.; Donnelly, C A; Ghani, A.C.; Anderson, R M

    2000-01-01

    An unresolved issue in the epidemiology of bovine spongiform encephalopathy (BSE) in the UK is what precisely determines the degree to which cases of disease in cattle are clustered within herds throughout the course of the epidemic. This paper presents an analysis of feed-borne transmission at the herd level and tests various models of case-clustering mechanisms, associated with heterogeneity in exposure to infectious feed, against observed epidemic pattern. We use an age-structured metapopu...

  1. Entrepreneurs as discoverers: the case of portuguese born globals

    OpenAIRE

    Dominguinhos, Pedro

    2002-01-01

    Comunicação apresentada em XVI Rent: Entrepreneurship and Small Business Traditionally, internationalisation has been study has a gradual process, where the firms start their operation to close markets with forms involving low risk. As time goes by, and the firm acquire experiential knowledge, the firm change his commitment to internationalisation, using more risky and demanding entry modes, and acting in distant markets. In the nineties, several firms, labelled born globals, ...

  2. Mortality differences between the foreign-born and locally-born population in France (2004-2007).

    Science.gov (United States)

    Boulogne, Roxane; Jougla, Eric; Breem, Yves; Kunst, Anton E; Rey, Grégoire

    2012-04-01

    In contrast to the situation in many European countries, the mortality of immigrants in France has been little studied. The main reasons for the lack of studies are based on ethical and ideological considerations. The objective of this study is to explore mortality by country of birth in Metropolitan (i.e. 'mainland') France. Complete mortality data were used to study the relative risks of mortality of the foreign- and locally-born populations by gender, age and cause of death for the period 2004-2007 in Metropolitan France. Analyses were conducted by countries of birth grouped into geographic areas and by the Human Development Index (HDI). The differentials in mortality between foreign-born and locally-born populations were not homogeneous. The figures varied by age (higher foreign-born mortality for the young; lower mortality for migrants aged 15-64 years), gender (female migrants more frequently had higher relative mortality than men migrants), country of birth (Eastern European-born migrants had higher mortality, while those born in Morocco, Central Asia, 'other Asian countries' and America had lower mortality) and cause of death (migrant mortality was higher overall for deaths caused by infectious diseases and diabetes, and lower for violent death and neoplasm). Moreover, mortality relative risks for male, violent deaths and cancer were positively associated with country-of-birth HDI, while female mortality and infectious disease mortality were negatively associated with country-of-birth HDI. Some important caveats have to be considered because the study did not control for individuals socioeconomic position in France, or length of residence in the host country. A strong healthy migrant effect was suggested and its intensity varies with age and gender (which may reflect different reasons for migration). For some specific causes of death, a lifestyle effect seems to explain mortality differentials. The associations between HDI and mortality show that mortality

  3. County Differences in Mortality among Foreign-Born Compared to Native Swedes 1970-1999

    OpenAIRE

    Björn Albin; Katarina Hjelm; Jan Ekberg; Sölve Elmståhl

    2012-01-01

    Background. Regional variations in mortality and morbidity have been shown in Europe and USA. Longitudinal studies have found increased mortality, dissimilarities in mortality pattern, and differences in utilization of healthcare between foreign- and native-born Swedes. No study has been found comparing mortality among foreign-born and native-born Swedes in relation to catchment areas/counties. Methods. The aim was to describe and compare mortality among foreign-born persons and native Swedes...

  4. Large baby syndrome in singletons born after frozen embryo transfer (FET)

    DEFF Research Database (Denmark)

    Pinborg, Anja; Henningsen, AA; Loft, A;

    2013-01-01

    Are singletons born after frozen embryo transfer (FET) at increased risk of being born large for gestational age (LGA) and if so, is this caused by intrinsic maternal factors or related to the freezing/thawing procedures?......Are singletons born after frozen embryo transfer (FET) at increased risk of being born large for gestational age (LGA) and if so, is this caused by intrinsic maternal factors or related to the freezing/thawing procedures?...

  5. Interpretation of second Born amplitudes in electron capture

    International Nuclear Information System (INIS)

    Exact sound Born amplitudes for 1s-1s electron capture are presented and interpreted in terms of contributions from intermediate states off the energy shell and on the energy shell. The classical model of Thomas corresponds to two-step scattering via one particular on-shell intermediate state. In the high-velocity limit for 1s-1s capture, this on-shell intermediate state of the Thomas model accounts for one-half of the total cross section, i.e., the second Born cross section. The other half comes from off-energy-shell intermediate states near the on-shell Thomas state. Above 5 MeV both the off-shell and on-shell amplitudes have a simple structure near the Thomas peak. Below 1 MeV, contributions from a broader range of intermediate states are evident in the amplitudes. Although the contribution from the Thomas state is not large below 1 MeV, other second Born effects are significant

  6. Review of vector-borne diseases in Hong Kong.

    Science.gov (United States)

    Ma, Siu-keung Edmond; Wong, Wang Christine; Leung, Chi-wah Ryan; Lai, Sik-to Thomas; Lo, Yee-chi Janice; Wong, Kai-hay Howard; Chan, Man-chung; Que, Tak-lun; Chow, Ka-wai Mary; Yuen, Ming-chi; Lau, Tin-wai Winnie; Simon, John

    2011-05-01

    The epidemiology of vector-borne diseases in Hong Kong has changed over the past decade but still poses a significant public health risk. We provided a comprehensive review of the epidemiological information and analysed the trends of major vector-borne diseases, including the vector situation in Hong Kong. The incidence of malaria has dropped dramatically in the past few decades and is now mainly an imported disease acquired from malaria endemic countries. Locally acquired dengue fever occurred in 2002 and 2003, and thereafter all cases were imported, mainly from Southeast Asia areas. Only a few local cases of Japanese encephalitis were reported in the past decade. In contrast, there is a notable increase in scrub typhus and spotted fever cases. The emergence of chikungunya fever in Asia and Indian Ocean countries also resulted in importation of human cases. Given the heavy traffic between this international city and other parts of the world, as well as the presence of vectors in this densely populated area, vigilance should be maintained against these infections. Comprehensive public health measures encompassing disease surveillance, vector surveillance and control measures with support from all sectors of the community are required to combat the old and newly emerging vector-borne diseases in Hong Kong.

  7. Food-borne bacteremic illnesses in febrile neutropenic children

    Directory of Open Access Journals (Sweden)

    Anselm Chi-wai Lee

    2011-08-01

    Full Text Available Bacteremia following febrile neutropenia is a serious complication in children with malignancies. Preventive measures are currently targeted at antimicrobial prophylaxis, amelioration of drug-induced neutropenia, and nosocomial spread of pathogens, with little attention to community-acquired infections. A retrospective study was conducted at a pediatric oncology center during a 3-year period to identify probable cases of food-borne infections with bacteremia. Twenty-one bacteremic illnesses affecting 15 children receiving chemotherapy or hematopoietic stem cell transplantation were reviewed. Three (14% episodes were highly suspected of a food-borne origin: a 17-year-old boy with osteosarcoma contracted Sphingomonas paucimobilis septicemia after consuming nasi lemak bought from a street hawker; a 2-year-old boy with acute lymphoblastic leukemia developed Chryseobacterium meningosepticum septicemia after a sushi dinner; a 2-year-old girl was diagnosed with acute lymphoblastic leukemia and Lactobacillus bacteremia suspected to be of probiotic origin. All of them were neutropenic at the time of the infections and the bacteremias were cleared with antibiotic treatment. Food-borne sepsis may be an important, but readily preventable, cause of bloodstream infections in pediatric oncology patients, especially in tropical countries with an abundance of culinary outlets.

  8. Food-borne bacteremic illnesses in febrile neutropenic children.

    Science.gov (United States)

    Lee, Anselm Chi-Wai; Siao-Ping Ong, Nellie Dawn

    2011-08-31

    Bacteremia following febrile neutropenia is a serious complication in children with malignancies. Preventive measures are currently targeted at antimicrobial prophylaxis, amelioration of drug-induced neutropenia, and nosocomial spread of pathogens, with little attention to community-acquired infections. A retrospective study was conducted at a pediatric oncology center during a 3-year period to identify probable cases of food-borne infections with bacteremia. Twenty-one bacteremic illnesses affecting 15 children receiving chemotherapy or hematopoietic stem cell transplantation were reviewed. Three (14%) episodes were highly suspected of a food-borne origin: a 17-year-old boy with osteosarcoma contracted Sphingomonas paucimobilis septicemia after consuming nasi lemak bought from a street hawker; a 2-year-old boy with acute lymphoblastic leukemia developed Chryseobacterium meningosepticum septicemia after a sushi dinner; a 2-year-old girl was diagnosed with acute lymphoblastic leukemia and Lactobacillus bacteremia suspected to be of probiotic origin. All of them were neutropenic at the time of the infections and the bacteremias were cleared with antibiotic treatment. Food-borne sepsis may be an important, but readily preventable, cause of bloodstream infections in pediatric oncology patients, especially in tropical countries with an abundance of culinary outlets. PMID:22184532

  9. [Sudden death in new-born babies (author's transl)].

    Science.gov (United States)

    Guilhaume, A

    This sudden death of a new-born baby, which had been thriving up to then, is a dramatic but not exceptional event. A systematic search for the etiology must be made, and this should include an autopsy in order that the diagnosis of "sudden and unexplained death" is confirmed only after eliminating all other possible causes. Knowledge of this syndrome has benefited from epidemiological surveys which have defined the previous clinical condition, but none of the many etiollotical hypotheses envisaged can take into account the total number of cases reported. One of the most recent cases developed apnoea during sleep, which could explain some unexpected deaths in new-born babies. This was discovered by polygraphic sleep recordings and confirmed by pathological examinations. These demonstrated indirect signs of chronic hypoxia which could have been related to the sudden death of the baby. Though there does not appear to be any relationship between the apnoea syndrome during sleep and these sudden and unexpected deaths, this hypothesis has opened up a new promising line of research which could help to identify new-born babies at risk from "sudden death", and to propose preventative measures. PMID:224505

  10. Food-borne bacteremic illnesses in febrile neutropenic children.

    Science.gov (United States)

    Lee, Anselm Chi-Wai; Siao-Ping Ong, Nellie Dawn

    2011-08-31

    Bacteremia following febrile neutropenia is a serious complication in children with malignancies. Preventive measures are currently targeted at antimicrobial prophylaxis, amelioration of drug-induced neutropenia, and nosocomial spread of pathogens, with little attention to community-acquired infections. A retrospective study was conducted at a pediatric oncology center during a 3-year period to identify probable cases of food-borne infections with bacteremia. Twenty-one bacteremic illnesses affecting 15 children receiving chemotherapy or hematopoietic stem cell transplantation were reviewed. Three (14%) episodes were highly suspected of a food-borne origin: a 17-year-old boy with osteosarcoma contracted Sphingomonas paucimobilis septicemia after consuming nasi lemak bought from a street hawker; a 2-year-old boy with acute lymphoblastic leukemia developed Chryseobacterium meningosepticum septicemia after a sushi dinner; a 2-year-old girl was diagnosed with acute lymphoblastic leukemia and Lactobacillus bacteremia suspected to be of probiotic origin. All of them were neutropenic at the time of the infections and the bacteremias were cleared with antibiotic treatment. Food-borne sepsis may be an important, but readily preventable, cause of bloodstream infections in pediatric oncology patients, especially in tropical countries with an abundance of culinary outlets.

  11. A framework to classify error in animal-borne technologies

    Directory of Open Access Journals (Sweden)

    Zackory eBurns

    2015-05-01

    Full Text Available The deployment of novel, innovative, and increasingly miniaturized devices on fauna, especially otherwise difficult to observe taxa, to collect data has steadily increased. Yet, every animal-borne technology has its shortcomings, such as limitations in its precision or accuracy. These shortcomings, here labelled as ‘error’, are not yet studied systematically and a framework to identify and classify error does not exist. Here, we propose a classification scheme to synthesize error across technologies, discussing basic physical properties used by a technology to collect data, conversion of raw data into useful variables, and subjectivity in the parameters chosen. In addition, we outline a four-step framework to quantify error in animal-borne devices: to know, to identify, to evaluate, and to store. Both the classification scheme and framework are theoretical in nature. However, since mitigating error is essential to answer many biological questions, we believe they will be operationalized and facilitate future work to determine and quantify error in animal-borne technologies. Moreover, increasing the transparency of error will ensure the technique used to collect data moderates the biological questions and conclusions.

  12. Observational constraints on electromagnetic Born-Infeld cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Bretón, Nora; Montiel, Ariadna [Dpto. de Física, Centro de Investigación y de Estudios Avanzados del I.P.N., Apdo. 14–740, D.F. (Mexico); Lazkoz, Ruth, E-mail: nora@fis.cinvestav.mx, E-mail: amontiel@fis.cinvestav.mx [Dpto. de Física Teórica, Universidad del País Vasco, Apdo. 644, E-48080, Bilbao (Spain)

    2012-10-01

    The cosmological model consisting of an electromagnetic Born-Infeld (BI) field coupled to a Robertson-Walker geometry is tested with the standard probes of SNIa, GRBs and direct Hubble parameter. The analysis shows that the inclusion of the nonlinear electromagnetic component does not contribute in a significative way to the observed expansion. The BI electromagnetic matter is considered with an abundance of Ω{sub BI}, that our best fit leads to Ω{sub BI} = 0.037 when tested with SNIa and the Hubble parameter data (0.1 < z < 1.75); while when tested with GRBs the result is of Ω{sub BI} = 0.304, which may indicate that this electrodynamics was important at epochs close to the appearance of large structure (z ≈ 7), although this late result has not as much reliability as that corresponding to the first two probes, since we know that the dispersion in GRBs data is still considerable. In view of these results we can rule out the electromagnetic Born-Infeld matter as the origin of the present accelerated expansion, this conclusion concerns exclusively the Born-Infeld theory.

  13. Review of vector-borne diseases in Hong Kong.

    Science.gov (United States)

    Ma, Siu-keung Edmond; Wong, Wang Christine; Leung, Chi-wah Ryan; Lai, Sik-to Thomas; Lo, Yee-chi Janice; Wong, Kai-hay Howard; Chan, Man-chung; Que, Tak-lun; Chow, Ka-wai Mary; Yuen, Ming-chi; Lau, Tin-wai Winnie; Simon, John

    2011-05-01

    The epidemiology of vector-borne diseases in Hong Kong has changed over the past decade but still poses a significant public health risk. We provided a comprehensive review of the epidemiological information and analysed the trends of major vector-borne diseases, including the vector situation in Hong Kong. The incidence of malaria has dropped dramatically in the past few decades and is now mainly an imported disease acquired from malaria endemic countries. Locally acquired dengue fever occurred in 2002 and 2003, and thereafter all cases were imported, mainly from Southeast Asia areas. Only a few local cases of Japanese encephalitis were reported in the past decade. In contrast, there is a notable increase in scrub typhus and spotted fever cases. The emergence of chikungunya fever in Asia and Indian Ocean countries also resulted in importation of human cases. Given the heavy traffic between this international city and other parts of the world, as well as the presence of vectors in this densely populated area, vigilance should be maintained against these infections. Comprehensive public health measures encompassing disease surveillance, vector surveillance and control measures with support from all sectors of the community are required to combat the old and newly emerging vector-borne diseases in Hong Kong. PMID:21679886

  14. Adult psychological functioning of individuals born with craniofacial anomalies.

    Science.gov (United States)

    Sarwer, D B; Bartlett, S P; Whitaker, L A; Paige, K T; Pertschuk, M J; Wadden, T A

    1999-02-01

    This study represents an initial investigation into the adult psychological functioning of individuals born with craniofacial disfigurement. A total of 24 men and women born with a craniofacial anomaly completed paper and pencil measures of body image dissatisfaction, self-esteem, quality of life, and experiences of discrimination. An age- and gender-matched control group of 24 non-facially disfigured adults also completed the measures. As expected, craniofacially disfigured adults reported greater dissatisfaction with their facial appearance than did the control group. Craniofacially disfigured adults also reported significantly lower levels of self-esteem and quality of life. Dissatisfaction with facial appearance, self-esteem, and quality of life were related to self-ratings of physical attractiveness. More than one-third of craniofacially disfigured adults (38 percent) reported experiences of discrimination in employment or social settings. Among disfigured adults, psychological functioning was not related to number of surgeries, although the degree of residual facial deformity was related to increased dissatisfaction with facial appearance and greater experiences of discrimination. Results suggest that adults who were born with craniofacial disfigurement, as compared with non-facially disfigured adults, experience greater dissatisfaction with facial appearance and lower self-esteem and quality of life; however, these experiences do not seem to be universal. PMID:9950526

  15. Impact of post-Born lensing on the CMB

    CERN Document Server

    Pratten, Geraint

    2016-01-01

    Lensing of the CMB is affected by post-Born lensing, producing corrections to the convergence power spectrum and introducing field rotation. We show numerically that the lensing convergence power spectrum is affected at the $\\lesssim 0.2\\%$ level on accessible scales, and that this correction and the field rotation are negligible for observations with arcminute beam and noise levels $\\gtrsim 1 \\mu {\\text{K}}\\,{\\text{arcmin}} $. The field rotation generates $\\sim 2.5\\%$ of the total lensing B-mode polarization amplitude ($0.2\\%$ in power on small scales), but has a blue spectrum on large scales, making it highly subdominant to the convergence B modes on scales where they are a source of confusion for the signal from primordial gravitational waves. Since the post-Born signal is non-linear, it also generates a bispectrum with the convergence. We show that the post-Born contributions to the bispectrum substantially change the shape predicted from large-scale structure non-linearities alone, and hence must be incl...

  16. Arthropod-borne infections in travelled dogs in Europe

    Directory of Open Access Journals (Sweden)

    Hamel Dietmar

    2013-01-01

    Full Text Available Pet animal movement is ever increasing within the European Union and in that context canine vectorborne infections gained a considerable importance. Information on these infections in travelled dogs is nevertheless limited. A first prospective study on vector-borne infections was conducted in 106 dogs travelling from Germany to countries in South and South-East Europe. The dogs were screened prior to and consecutively up to three times after travel by haematological (Giemsa-stained buffy coat smears, Knott’s-Test, molecular biological (PCR as well as serological (IFAT, DiroChek®-ELISA methods for arthropod-borne infections. Seven animals were seropositive for antibodies against Babesia canis sspp., Leishmania spp. and/or Ehrlichia canis prior to travel to Italy, Spain, France, Croatia, Greece, or Hungary. In the consecutive screening after return there was no increase in the number of seropositive dogs. None was positive in direct methods. The mean duration of the stay was 17 days and 51% of the dogs were prophylactically treated with ectoparasiticidal formulations. Preliminary data from this study on canine vector-borne infections indicate a low risk for infection during a limited single stay in endemic countries.

  17. Phenotypic Differences in Individuals with Autism Spectrum Disorder Born Preterm and at Term Gestation

    Science.gov (United States)

    Bowers, Katherine; Wink, Logan K.; Pottenger, Amy; McDougle, Christopher J.; Erickson, Craig

    2015-01-01

    The objective of the study was to characterize the phenotype of males and females with autism spectrum disorder born preterm versus those born at term. Descriptive statistical analyses identified differences between male and female autism spectrum disorder subjects born preterm compared to term for several phenotypic characteristics and…

  18. Foreign-Born Instructors in the U.S.: Intercultural Competence, Teaching Strategies, and Job Satisfaction

    Science.gov (United States)

    Wasilik, Oksana

    2011-01-01

    This study examines intercultural competence, teaching strategies, and job satisfaction of foreign-born instructors in a small U.S. higher education institution. The research questions addressed by this study are: (1) How do foreign-born instructors score on intercultural competence? (2) How do foreign-born instructors' teaching strategies differ…

  19. The Training Requirements of Foreign-Born Workers in Different Countries

    Science.gov (United States)

    Ryan, Chris; Sinning, Mathias

    2012-01-01

    The training requirements of foreign-born workers may be different from those of native-born workers in similar jobs. Over recent decades Australian immigration policy has focused predominantly on accepting high-skilled migrants. Although this focus has resulted in the successful integration of foreign-born workers into the Australian labour…

  20. Behavioural skills in 7 year old children born post-term

    DEFF Research Database (Denmark)

    Olesen, Annette Wind; Olsen, Jørn; Zhu, Jin Liang

    2014-01-01

    and their children. All singletons born in gestational week 39-45 were identified, and then restricted to children whose mothers filled out a Strength and Difficulties Questionnaire (STQ) when they were seven years of age. The study population constituted 33842 singletons (21249 born at term and 12593 born post...

  1. School functioning in 8- to 18-year-old children born after in vitro fertilization

    NARCIS (Netherlands)

    Wagenaar, Karin; Ceelen, Manon; Weissenbruch, van Mirjam; Knol, Dirk; Delemarre-van de Waal, Henriette; Huisman, Jaap

    2008-01-01

    The aim of this study was to examine the school functioning of 8- to 18-year-old children born after in vitro fertilization (IVF). We compared 233 children born after IVF to 233 matched control children born spontaneously from parents with fertility problems on measures of education level, general c

  2. Certain Cancers Seem Less Likely for Kids of Hispanic Moms Born Outside U.S.

    Science.gov (United States)

    ... Likely for Kids of Hispanic Moms Born Outside U.S. Analyzing immigrant population can help identify tumor causes, ... 2012. The analysis was limited to children of U.S.-born white, U.S.-born Hispanic, or non-U.S.- ...

  3. Educational Needs of School-Aged Children Born Very and Extremely Preterm: A Review

    Science.gov (United States)

    Hornby, Garry; Woodward, Lianne J.

    2009-01-01

    Recent decades have witnessed dramatically improved survival rates for infants born prematurely, especially those born very and extremely preterm. Follow-up studies concerned with long-term neurodevelopmental outcomes for children born preterm indicate that these children are at high risk for a range of cognitive, learning, neuromotor, and…

  4. Pharmacological activation of CB2 receptors counteracts the deleterious effect of ethanol on cell proliferation in the main neurogenic zones of the adult rat brain

    Science.gov (United States)

    Rivera, Patricia; Blanco, Eduardo; Bindila, Laura; Alen, Francisco; Vargas, Antonio; Rubio, Leticia; Pavón, Francisco J.; Serrano, Antonia; Lutz, Beat; Rodríguez de Fonseca, Fernando; Suárez, Juan

    2015-01-01

    Chronic alcohol exposure reduces endocannabinoid activity and disrupts adult neurogenesis in rodents, which results in structural and functional alterations. Cannabinoid receptor agonists promote adult neural progenitor cell (NPC) proliferation. We evaluated the protective effects of the selective CB1 receptor agonist ACEA, the selective CB2 receptor agonist JWH133 and the fatty-acid amide-hydrolase (FAAH) inhibitor URB597, which enhances endocannabinoid receptor activity, on NPC proliferation in rats with forced consumption of ethanol (10%) or sucrose liquid diets for 2 weeks. We performed immunohistochemical and stereological analyses of cells expressing the mitotic phosphorylation of histone-3 (phospho-H3+) and the replicating cell DNA marker 5-bromo-2'-deoxyuridine (BrdU+) in the main neurogenic zones of adult brain: subgranular zone of dentate gyrus (SGZ), subventricular zone of lateral ventricles (SVZ) and hypothalamus. Animals were allowed ad libitum ethanol intake (7.3 ± 1.1 g/kg/day) after a controlled isocaloric pair-feeding period of sucrose and alcoholic diets. Alcohol intake reduced the number of BrdU+ cells in SGZ, SVZ, and hypothalamus. The treatments (URB597, ACEA, JWH133) exerted a differential increase in alcohol consumption over time, but JWH133 specifically counteracted the deleterious effect of ethanol on NPC proliferation in the SVZ and SGZ, and ACEA reversed this effect in the SGZ only. JWH133 also induced an increased number of BrdU+ cells expressing neuron-specific β3-tubulin in the SVZ and SGZ. These results indicated that the specific activation of CB2 receptors rescued alcohol-induced impaired NPC proliferation, which is a potential clinical interest for the risk of neural damage in alcohol dependence. PMID:26483633

  5. Measurement equivalence of four psychological questionnaires in native-born Germans, Russian-speaking immigrants, and native-born Russians.

    Science.gov (United States)

    Hirsch, Oliver; Donner-Banzhoff, Norbert; Bachmann, Viktoria

    2013-07-01

    Psychological constructs depend on cultural context. It is therefore important to show the equivalence of measurement instruments in cross-cultural research. There is evidence that in Russian-speaking immigrants, cultural and language issues are important in health care. We examined measurement equivalence of the Patient Health Questionnaire-9 (PHQ-9), the Patient Health Questionnaire-15 (PHQ-15), the Hamburg Self-Care Questionnaire (HamSCQ), and the questionnaire on communication preferences of patients with chronic illness (KOPRA) in native-born Germans, Russian-speaking immigrants living in Germany, and native-born Russians living in the former Soviet Union (FSU). All four questionnaires fulfilled requirements of measurement equivalence in confirmatory factor analyses and analyses of differential item functioning. The Russian translations can be used in Russian-speaking immigrants and native-born Russians. This offers further possibilities for cross-cultural research and for an improvement in health care research in Russian-speaking immigrants in Germany. The most pronounced differences occurred in the KOPRA, which point to differences in German and Russian health care systems.

  6. 49 CFR 71.8 - Mountain zone.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Mountain zone. 71.8 Section 71.8 Transportation Office of the Secretary of Transportation STANDARD TIME ZONE BOUNDARIES § 71.8 Mountain zone. The fourth zone, the mountain standard time zone, includes that part of the United States that is west of...

  7. Mechanical properties of fracture zones

    International Nuclear Information System (INIS)

    Available data on mechanical characteristics of fracture zones are compiled and discussed. The aim is to improve the basis for adequate representation of fracture zones in geomechanical models. The sources of data researched are primarily borehole investigations and case studies in rock engineering, involving observations of fracture zones subjected to artificial load change. Boreholes only yield local information about the components of fracture zones, i.e. intact rock, fractures and various low-strength materials. Difficulties are therefore encountered in evaluating morphological and mechanical properties of fracture zones from borehole data. Although often thought of as macroscopically planar features, available field data consistently show that fracture zones are characterized by geometrical irregularities such as thickness variations, surface undulation and jogs. These irregularities prevail on all scales. As a result, fracture zones are on all scales characterized by large, in-plane variation of strength- and deformational properties. This has important mechanical consequences in terms of non-uniform stress transfer and complex mechanisms of shear deformation. Field evidence for these findings, in particular results from the underground research laboratory in Canada and from studies of induced fault slip in deep mines, is summarized and discussed. 79 refs

  8. Formalized morphostructural zoning of the mountain zone of the Andes

    Energy Technology Data Exchange (ETDEWEB)

    Gabrielov, A.M.; Gvishiani, A.D.; Zhidkov, M.P.

    1982-01-01

    A plan is presented for morphostructural zoning of the Andes compiled according to formalized signs for purposes of seismic forecasting. Characteristics are presented for the basic morphostructural subdivisions of the Andes.

  9. Problems of Chernobyl exclusion zone

    International Nuclear Information System (INIS)

    The collection comprises the results of researches and design activity in the ChNPP exclusion zone with the aim to develop technology, equipment and instruments for RAW management and accident clean-up, studying of the composition and structure of the activity solid bearers in the soil of the exclusion zone and transformation of the radionuclides in the nearest zone of ChNPP. Much attention is paid to medical and biological problems of the accident influence on the flora, fauna and people's health labour conditions and incidence of the people involved

  10. Problems of Chornobyl Exclusion Zone

    International Nuclear Information System (INIS)

    The collection comprises the results of researches and design activity in the ChNPP exclusion zone with the aim to develop technology, equipment and instruments for RAW management and accident clean-up, studying of the composition and structure of the activity solid bearers in the soil of the exclusion zone and transformation of the radionuclides in the nearest zone of ChNPP. Much attention is paid to medical and biological problems of the accident influence on the flora, fauna and people's health, labour conditions and incidence of the people involved.

  11. Antimicrobial Activity of Solanum torvum Swart. Against Important Seed Borne Pathogens of Paddy

    Directory of Open Access Journals (Sweden)

    V. Lalitha

    2010-01-01

    Full Text Available Aqueous and Solvent extracts of leaves of S. torvum viz., Petroleum ether, Benzene, Chloroform, Methanol and Ethanol were tested in vitro for antimicrobial activity following the procedures of poisoned food technique and cup diffusion method against some important seed borne pathogens of paddy viz, Pyricularia oryzae, Alternaria alternata, Bipolaris oryzae, Tricoconis padwickii, Dreschlera tetramera, D. halodes, Curvularia lunata, F. oxysporum, F. moniliformae, F. solani and Xanthomonas oryzae. Aqueous extracts of leaves (at 25% concentration showed 100, 47.44, 60.47, 71.50, 56.11, 63.33, 78.62, 66.66, 47.44 and 46.27% inhibition of the test pathogens respectively. Highly significant antifungal activity was observed in Methanolic and ethanolic extract. The percentage inhibition of the test pathogenic fungi in Methanolic extract was 100% (P.oryzae, 74.42 (A. alternata, 65.68 (B oryzae, 87.62 (C .lunata, 100% (T. padwickii, 63.33 (D.halodes, 60.31 D. (tetramera, 76.01 (F.moniliformae, 59.21 (F. oxysporum, 43.91% (F.solani and zone of inhibition of Xanthomonas campestris pv oryzae was 18 and 30mm in Methanol and ethanol extract.

  12. Emergence of tick-borne encephalitis in new endemic areas in Austria: 42 years of surveillance.

    Science.gov (United States)

    Heinz, F X; Stiasny, K; Holzmann, H; Kundi, M; Sixl, W; Wenk, M; Kainz, W; Essl, A; Kunz, C

    2015-04-02

    Human infections with tick-borne encephalitis (TBE)virus are a public health concern in certain regions of Europe, central and eastern Asia. Expansions of endemic areas and increased incidences have been associated with different factors including ecological changes supporting tick reproduction, socioeconomic changes increasing human outdoor activities and climatic changes favouring virus circulation in natural foci. Austria is among the most strongly affected countries in Central Europe, but the annual number of cases has strongly declined due to vaccination. Here,we have analysed changes of the incidence of TBE in the unvaccinated population of all federal states of Austria over a period of 42 years. The overall incidence in Austria has remained constant, but new strongly affected endemic regions have emerged in alpine valleys in the west of Austria. In parallel, the incidence in low-land regions in the north-east of the country is decreasing. There is no evidence for a shift to higher altitudes of infection sites in the traditional TBE zones,but the average altitudes of some newly established endemic areas in the west are significantly higher. Our analyses underscore the focal nature of TBE endemic areas and the potential of TBE virus to emerge in previously unaffected regions.

  13. Epidemiology of tick-borne encephalitis (TBE) in Europe and its prevention by available vaccines.

    Science.gov (United States)

    Amicizia, Daniela; Domnich, Alexander; Panatto, Donatella; Lai, Piero Luigi; Cristina, Maria Luisa; Avio, Ulderico; Gasparini, Roberto

    2013-05-01

    Tick-borne Encephalitis (TBE), which is caused by a Flavivirus, is the most common tick-transmitted disease in Central and Eastern Europe and Russia. Today, TBE is endemic in 27 European countries, and has become an international public health problem. The epidemiology of TBE is changing owing to various factors, such as improvements in diagnosis and case reporting, increased recreational activities in areas populated by ticks, and changes in climatic conditions affecting tick habitats. Vaccination remains the most effective protective measure against TBE for people living in risk zones, occupationally exposed subjects and travelers to endemic areas. The vaccines currently in use are FSME-Immun(®), Encepur(®), EnceVir(®) and TBE vaccine Moscow(®). The numerous studies performed on the efficacy and safety of these vaccines have shown a high level of immunogenicity and an excellent safety profile. Several studies have also shown a high level of cross-protection among strains belonging to different subtypes.   In the present paper we attempted to describe the continuously changing epidemiology of TBE in European States and to overview clinical development of available vaccines paying particular attention on cross-protection elicited by the vaccines.

  14. Global from the Start: The Characteristics of Born-Global Firms in the Technology Sector

    Directory of Open Access Journals (Sweden)

    Stoyan Tanev

    2012-03-01

    Full Text Available This article provides insights from recent research on firms that are "born global". A born-global firm is a venture launched to exploit a global niche from the first day of its operations. The insights in this article are relevant to technology entrepreneurs and top management teams of new technology firms. After discussing various definitions for the term "born global" and identifying the main characteristics of born-global firms, this article lists a few salient characteristics of firms that are born global in the technology sector. The article concludes by identifying opportunities for future research.

  15. Clinico-epidemiologichesky aspects of the mixed tick-borne infections in the endemic region

    Directory of Open Access Journals (Sweden)

    E. S. Aleshkovskaya

    2013-01-01

    Full Text Available Detection of clinico-epidemiological features of the mixed tick-borne infections – tick-borne Lyme disease and a human granulocytic anaplasmosis was the purpose of the conducted research. During the spring – summer period 146 patients with tick-borne borreliosis were surveyed. As a result at 45 (30,82% patients authentically diagnosed the mixed tick-borne infection. Features of clinical manifestations of a mixed tick-borne infection revealed: catarrhal phenomena (20%, liver defeats (33%, nephros (31, 7%, frequent secondary erythems (20%. Changes in haemogram defined: thrombocytopenia (42,2%, anemia (20%, leukopenia (13,3%.

  16. Perinatal outcomes in 6,338 singletons born after intrauterine insemination in Denmark, 2007 to 2012

    DEFF Research Database (Denmark)

    Malchau, Sara Sofia; Loft, Anne; Henningsen, Anna-Karina Aaris;

    2014-01-01

    OBJECTIVE: To study perinatal outcomes in singletons born after intrauterine insemination (IUI) compared with children born after in vitro fertilization (IVF), intracytoplasmic sperm injection, and spontaneous conception (SC), and to assess predictors of poor outcome in singletons born after IUI......, exploring the effect of ovarian stimulation. DESIGN: National cohort study, 2007-2012. SETTING: Danish national registries. PATIENT(S): Four thousand two hundred twenty-eight singletons born after insemination with partner semen (IUI-H) and 1,881 singletons born after insemination with donor semen...

  17. Global from the Start: The Characteristics of Born-Global Firms in the Technology Sector

    DEFF Research Database (Denmark)

    Tanev, Stoyan

    2016-01-01

    This article provides insights from recent research on firms that are “born global”. A born-global firm is a venture launched to exploit a global niche from the first day of its operations. The insights in this article are relevant to technology entrepreneurs and top management teams of new...... technology firms. After discussing various definitions for the term “born global” and identifying the main characteristics of born-global firms, this article lists a few salient characteristics of firms that are born global in the technology sector. The article concludes by identifying opportunities...

  18. Comparing the relative importance of water-borne cues and direct grazing for the induction of defenses in the brown seaweed Fucus vesiculosus.

    Science.gov (United States)

    Flöthe, Carla R; John, Uwe; Molis, Markus

    2014-01-01

    Some seaweed species have been shown to release water-borne cues after herbivore attack, for example, to attract natural enemies of the herbivore. These cues may also be sensed by neighboring seaweeds and used to adjust their defenses in anticipation of a possible herbivore attack. Several studies indicated information transfer between seaweed individuals in the past, including the brown seaweed Fucus vesiculosus. Previous work showed induction of defenses in F. vesiculosus in response to water-borne cues released by isopod-grazed conspecifics. In contrast, another study on induced responses after exposure to cues from isopod-grazed neighbors using the same seaweed species yielded contradictory results. This study reassessed the ability of F. vesiculosus individuals to sense water-borne cues released by isopod-grazed neighbors in a series of experiments that monitored F. vesiculosus palatability in response to direct grazing by Idotea baltica and water-borne cues from isopod-grazed neighbors relative to unmanipulated seaweed pieces. Two-choice feeding assays were conducted with both fresh and reconstituted seaweed pieces. Direct grazing by I. baltica induced a chemical defense in F. vesiculosus, confirming results of previous studies. In contrast, evidence for increased herbivore resistance in seaweed pieces that were located downstream of isopod-grazed F. vesiculosus could not be provided. The lack of defense induction in response to grazing of conspecific neighbors may be explained by the environmental conditions and the scattered distribution of F. vesiculosus individuals in the intertidal zone of Helgoland, which may render resource investment in the emission and/or response to water-borne cues at this site unprofitable. PMID:25279662

  19. Comparing the relative importance of water-borne cues and direct grazing for the induction of defenses in the brown seaweed Fucus vesiculosus.

    Directory of Open Access Journals (Sweden)

    Carla R Flöthe

    Full Text Available Some seaweed species have been shown to release water-borne cues after herbivore attack, for example, to attract natural enemies of the herbivore. These cues may also be sensed by neighboring seaweeds and used to adjust their defenses in anticipation of a possible herbivore attack. Several studies indicated information transfer between seaweed individuals in the past, including the brown seaweed Fucus vesiculosus. Previous work showed induction of defenses in F. vesiculosus in response to water-borne cues released by isopod-grazed conspecifics. In contrast, another study on induced responses after exposure to cues from isopod-grazed neighbors using the same seaweed species yielded contradictory results. This study reassessed the ability of F. vesiculosus individuals to sense water-borne cues released by isopod-grazed neighbors in a series of experiments that monitored F. vesiculosus palatability in response to direct grazing by Idotea baltica and water-borne cues from isopod-grazed neighbors relative to unmanipulated seaweed pieces. Two-choice feeding assays were conducted with both fresh and reconstituted seaweed pieces. Direct grazing by I. baltica induced a chemical defense in F. vesiculosus, confirming results of previous studies. In contrast, evidence for increased herbivore resistance in seaweed pieces that were located downstream of isopod-grazed F. vesiculosus could not be provided. The lack of defense induction in response to grazing of conspecific neighbors may be explained by the environmental conditions and the scattered distribution of F. vesiculosus individuals in the intertidal zone of Helgoland, which may render resource investment in the emission and/or response to water-borne cues at this site unprofitable.

  20. When are new hippocampal neurons, born in the adult brain, integrated into the network that processes spatial information?

    Directory of Open Access Journals (Sweden)

    C Jimena Sandoval

    Full Text Available Adult-born neurons in the dentate gyrus (DG functionally integrate into the behaviorally relevant hippocampal networks, showing a specific Arc-expression response to spatial exploration when mature. However, it is not clear when, during the 4- to 6-week interval that is critical for survival and maturation of these neurons, this specific response develops. Therefore, we characterized Arc expression after spatial exploration or cage control conditions in adult-born neurons from rats that were injected with BrdU on one day and were sacrificed 1, 7, 15, 30, and 45 days post-BrdU injection (PBI. Triple immunostaining for NeuN, Arc, and BrdU was analyzed through the different DG layers. Arc protein expression in BrdU-positive cells was observed from day 1 to day 15 PBI but was not related to behavioral stimulation. The specific Arc-expression response to spatial exploration was observed from day 30 and 45 in about 5% of the BrdU-positive cell population. Most of the BrdU-positive neurons expressing Arc in response to spatial exploration (∼90% were located in DG layer 1, and no Arc expression was observed in cells located in the subgranular zone (SGZ. Using the current data and that obtained previously, we propose a mathematical model suggesting that new neurons are unlikely to respond to exploration by expressing Arc after they are 301 days old, and also that in a 7-month-old rat the majority (60% of the neurons that respond to exploration must have been born during adulthood; thus, suggesting that adult neurogenesis in the DG is highly relevant for spatial information processing.

  1. Zoonotic mosquito-borne flaviviruses: worldwide presence of agents with proven pathogenicity and potential candidates of future emerging diseases.

    Science.gov (United States)

    Weissenböck, H; Hubálek, Z; Bakonyi, T; Nowotny, N

    2010-01-27

    An update on the mosquito-borne flavivirus species including certain subtypes, as listed in the Eighth Report of the International Committee on Taxonomy of Viruses, is given. Special emphasis is placed on viruses which have been shown to cause diseases in animals, and viruses for which no pathogenicity has been proven yet. Several recent examples (Usutu virus and lineage-2 West Nile virus in central Europe, Zika virus in Micronesia) have shown that sources providing information on such scientifically largely neglected viruses are valuable tools for scientists and public health officials having to deal with such disease emergences. Furthermore the effects of global warming will lead to introduction of competent mosquito vectors into temperate climate zones and will increase efficiency of viral replication in less competent vector species. This, facilitated by rising global travel and trade activities, will facilitate introduction and permanent establishment of mosquito-borne viruses, some of which may become of public health or veterinary concern, into novel environments, e.g. industrialized countries worldwide.

  2. NEPR Geographic Zone Map 2015

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This geographic zone map was created by interpreting satellite and aerial imagery, seafloor topography (bathymetry model), and the new NEPR Benthic Habitat Map...

  3. In situ vadose zone bioremediation.

    Science.gov (United States)

    Höhener, Patrick; Ponsin, Violaine

    2014-06-01

    Contamination of the vadose zone with various pollutants is a world-wide problem, and often technical or economic constraints impose remediation without excavation. In situ bioremediation in the vadose zone by bioventing has become a standard remediation technology for light spilled petroleum products. In this review, focus is given on new in situ bioremediation strategies in the vadose zone targeting a variety of other pollutants such as perchlorate, nitrate, uranium, chromium, halogenated solvents, explosives and pesticides. The techniques for biostimulation of either oxidative or reductive degradation pathways are presented, and biotransformations to immobile pollutants are discussed in cases of non-degradable pollutants. Furthermore, research on natural attenuation in the vadose zone is presented.

  4. Development Zones Flourish in Beijing

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Based on the Beijing Municipal Government's plans for developing the city and neighboring suburbs,and after more than 10 years in development,the Beijing Development Zones have taken shape,each with their own characteristics.

  5. ShoreZone Survey Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset is a point file showing GPS trackline data collected during a ShoreZone aerial imaging survey. This flight trackline is recorded at 1-second intervals...

  6. Offshore Wind Technology Depth Zones

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Coastal bathymetric depth, measured in meters at depth values of: -30, -60, -900 Shallow Zone (0-30m): Technology has been demonstrated on a commercial scale at...

  7. INCIDENCE OF NEONATAL HYPERBILIRUBINEMEA IN TERM NEW BORNS AT KBNTGH

    Directory of Open Access Journals (Sweden)

    Mujumdar

    2015-11-01

    Full Text Available AIM AND SCOPE: We conducted this study to estimate the incidence of hyperbilirubinemia in term new born with birth weight >2.5 kgs born at neonatal care unit of KBNTGH, and to determine the underlying causes, which would be of value in identifying and implementing strategies to prevent morbidity from this condition. BACKGROUND: Management of hyperbilirubinemia remains a challenge for neonatal medicine because of the risk for serious neurological complications related to the toxicity of bilirubin. MATERIALS AND METHODS: From January 2014 to January 2015, we screened 525 newborns born at KBNTGH (Khaja Bandanawaz Teaching & General Hospital attached to Khaja Bandanawaz Institute of Medical Scienceswith complaints of yellowish discoloration of skin were screened for jaundice. Infants aged 3–5 days and with unconjugated hyperbilirubinemia were included for assessment if they had a peak serum total bilirubin level exceeding 10 mg/dl. Sex, birth weight, gestational age, breast feeding, type of birth, presence of facial bruising (Including cephalohematoma and ABO group were noted. Patients with Toxoplasma or Cytomegalovirus infection, hepatic insufficiency, or suspected drug-induced hyperbilirubinemia were excluded from more detailed analysis. RESULTS: Our year-long nursery sample examined otherwise healthy-appearing term infants with birth weigth>2.5kgs for the prevalence of hyperbilirubinemia (Defined as bilirubin levels exceeding 6 mg/dL [11mol/L]. We found hyperbilirubinemia in 19% (100/525. Among the patients with hyperbilirubinemia, 1.2% had peak levels of bilirubin 20 mg/dL, levels which are generally considered to be potentially neurotoxic. CONCLUSIONS: In our clinic experience, hyperbilirubinemia was generally a serious medical issue and one whose etiology can usually be well defined.

  8. Stepped conical zone plate antenna

    Science.gov (United States)

    Wiltse, James C.

    2001-07-01

    The Fresnel zone plate lens was invented and developed for optical frequencies. However, fabrication difficulties at the short optical wavelengths have prevented obtain good efficiencies. At longer microwave or millimeter-wavelengths fabrication is easier and phase correcting zone plate antennas have been used to obtain good efficiencies. This paper describes a new type of phase correcting zone plate having even better efficiency, namely a diffraction efficiency of 99 percent compared to a true lens, and an overall efficiency much better than a true lens. For the usual zone plate antenna employed at microwave or millimeter wavelengths, path length adjustment is accomplished by cutting different depths in a dielectric plate or by using two or more dielectrics having different dielectric constants. The new design uses a tilted cut in a dielectric plate, which more accurately matches the shape of a true lens and produces much lower phase error. The construction is still near and can be made for example, by a milling machine with a tilted bit. For a circular zone plate, the lens is a stepped conical or tapered shape. Because the phase steps are small, the far-field antenna pattern is excellent and sidelobe-levels are very low. Analysis of typical configurations will be given, showing that phase errors are small, lower than those for an eighth-wave corrected phase zone plate.

  9. Minimization of structure-borne noise in lightweight buildings

    DEFF Research Database (Denmark)

    Niu, Bin; Olhoff, Niels

    2012-01-01

    of the base plate is studied for optimizing machinery installation. Furthermore, periodic mounts are optimized for the noise reduction. Finally, a modular model of a lightweight building is developed for design optimization of dimensions and connections of modules in the building for decreasing machinery......This paper deals with the problem of minimizing the structure-borne noise induced in a room by machinery vibration. A generalized system consisting of the machine, the base plate, resilient mounts, the floor plate and the room cavity is developed for analysis and optimization. Topological design...

  10. Non-BPS Dirac-Born-Infeld Solitons

    OpenAIRE

    Ioannidou, Theodora; Papadopoulos, George; Sutcliffe, Paul(Department of Mathematical Sciences, Durham University, South Road, Durham, DH1 3LE, U.K.)

    1999-01-01

    We show that CPn sigma model solitons solve the field equations of a Dirac-Born-Infeld (DBI) action and, furthermore, we prove that the non-BPS soliton/anti-soliton solutions of the sigma model also solve the DBI equations. Using the moduli space approximation we compare the dynamics of the BPS sigma model solitons with that of the associated DBI solitons. We find that for the CP1 case the metric on the moduli space of sigma model solitons is identical to that of the moduli space of DBI solit...

  11. Nativity concentration and internal migration among the foreign-born.

    Science.gov (United States)

    Kritz, M M; Nogle, J M

    1994-08-01

    Are immigrants who live in states where large numbers of their compatriots reside more or less likely to migrate than those who live in other states? Using 1980 U.S. Census data to address that question, the analysis shows that nativity concentration deters interstate migration but not migration within the same state. Residing in a state where fellow nationals live is a more important determinant of internal migration than human capital, immigration status, or a state's unemployment rate. New York State residence in 1975 also promotes interstate migration. This research suggests that social dimensions should be taken into account in modeling internal migration of the foreign-born. PMID:7828769

  12. Pointing System for the Balloon-Borne Astronomical Payloads

    CERN Document Server

    Nirmal, K; Mathew, Joice; Sarpotdar, Mayuresh; Suresh, Ambily; Prakash, Ajin; Safonova, Margarita; Murthy, Jayant

    2016-01-01

    We describe the development and implementation of a light-weight, fully autonomous 2-axis pointing and stabilization system designed for balloon-borne astronomical payloads. The system is developed using off-the-shelf components such as Arduino Uno controller, HMC 5883L magnetometer, MPU-9150 Inertial Measurement Unit (IMU) and iWave GPS receiver unit. It is a compact and rugged system which can also be used to take images/video in a moving vehicle, or in areal photography. The system performance is evaluated from the ground, as well as in conditions simulated to imitate the actual flight by using a tethered launch.

  13. Balloon-Borne System Would Aim Instrument Toward Sun

    Science.gov (United States)

    Polites, M. E.

    1992-01-01

    Proposed system including digital control computer, control sensors, and control actuators aims telescope or other balloon-borne instrument toward Sun. Pointing system and instrument flown on gondola, suspended from balloon. System includes reaction wheel, which applies azimuthal control torques to gondola, and torque motor to apply low-frequency azimuthal torques between gondola and cable. Three single-axis rate gyroscopes measure yaw, pitch, and roll. Inclinometer measures roll angle. Two-axis Sun sensor measures deviation, in yaw and pitch, of attitude of instrument from line to apparent center of Sun. System provides initial coarse pointing, then maintains fine pointing.

  14. Spatial model for transmission of mosquito-borne diseases

    Science.gov (United States)

    Kon, Cynthia Mui Lian; Labadin, Jane

    2015-05-01

    In this paper, a generic model which takes into account spatial heterogeneity for the dynamics of mosquito-borne diseases is proposed. The dissemination of the disease is described by a system of reaction-diffusion partial differential equations. Host human and vector mosquito populations are divided into susceptible and infectious classes. Diffusion is considered to occur in all classes of both populations. Susceptible humans are infected when bitten by infectious mosquitoes. Susceptible mosquitoes bite infectious humans and become infected. The biting rate of mosquitoes is considered to be density dependent on the total human population in different locations. The system is solved numerically and results are shown.

  15. EFFICACY OF BIOAGENTS AGAINST SEED BORNE FUNGI OF RICE

    Directory of Open Access Journals (Sweden)

    N. Y. Halgekar

    2014-09-01

    Full Text Available The effect of different antagonist ’ viz. Trichoderma viride Pseudomonas fluorescens and Bacillus substilis were evaluated against different seed borne fungi of rice by dual culture technique. Among three bio agents Trichoderma viride (42.59 to 73.33% followed by Bacillus subtilis and Psuedomonas fluorescens over control. Significant suppression of radial mycelial growth of Drechslera oryzae by Trichoderma viride, and Trichoderma harzianum in dual culture and Inhibition of Curvularia lunata causing black kernel in rice with Bacillus subtilis (97.77% followed by Trichoderma viride (96.44% and Trichoderma harzianum (93.50% in dual culture method.

  16. Determinants of oral bioavailability of soil-borne contaminants

    OpenAIRE

    Oomen, Agnes Guadalupe

    2001-01-01

    Children ingest soil, either accidentally via hand-to-mouth behavior or deliberately. In this manner, a child ingests on average between 50 and 200 mg soil/day, although amounts of as much as 60 g/day have also been observed. Hence, soil ingestion can be a main route of exposure to soil-borne contaminants to children. To estimate the health risk associated to this exposure route, and to assess intervention values for contaminants in soils, one needs to know the oral bioavailability of the soi...

  17. A Recursive Born Approach to Nonlinear Inverse Scattering

    CERN Document Server

    Kamilov, Ulugbek S; Mansour, Hassan; Boufounos, Petros T

    2016-01-01

    The Iterative Born Approximation (IBA) is a well-known method for describing waves scattered by semi-transparent objects. In this paper, we present a novel nonlinear inverse scattering method that combines IBA with an edge-preserving total variation (TV) regularizer. The proposed method is obtained by relating iterations of IBA to layers of a feedforward neural network and developing a corresponding error backpropagation algorithm for efficiently estimating the permittivity of the object. Simulations illustrate that, by accounting for multiple scattering, the method successfully recovers the permittivity distribution where the traditional linear inverse scattering fails.

  18. Air-borne contact dermatitis caused exclusively by xanthium strumarium

    Directory of Open Access Journals (Sweden)

    Pasricha J

    1995-01-01

    Full Text Available Most cases having air-borne contact dermatitis (ABCD in India are considered to be caused by Parthenium hysterophorus. In some cases however, other plants have also been noticed to give positive patch test reactions. We are reporting two cases presenting as ABCD who showed positive patch tests with Xanthium strumarium while the patch tests with Parthenium hysterophorus were negative. It is therefore necessary to realise that every case of ABCD is not caused by Parthenium, and patch testing with Parthenium alone can lead to serious mistakes.

  19. Air-borne contact dermatitis caused exclusively by xanthium strumarium.

    Science.gov (United States)

    Pasricha, J S; Verma, K K; D'Souza, P

    1995-01-01

    Most cases having air-borne contact dermatitis (ABCD) in India are considered to be caused by Parthenium hysterophorus. In some cases however, other plants have also been noticed to give positive patch test reactions. We are reporting two cases presenting as ABCD who showed positive patch tests with Xanthium strumarium while the patch tests with Parthenium hysterophorus were negative. It is therefore necessary to realise that every case of ABCD is not caused by Parthenium, and patch testing with Parthenium alone can lead to serious mistakes. PMID:20953020

  20. Tick-Borne Relapsing Fever Spirochetes in the Americas

    Directory of Open Access Journals (Sweden)

    Job E. Lopez

    2016-08-01

    Full Text Available Relapsing fever spirochetes are tick- and louse-borne pathogens that primarily afflict those in impoverished countries. Historically the pathogens have had a significant impact on public health, yet currently they are often overlooked because of the nonspecific display of disease. In this review, we discuss aspects of relapsing fever (RF spirochete pathogenesis including the: (1 clinical manifestation of disease; (2 ability to diagnose pathogen exposure; (3 the pathogen’s life cycle in the tick and mammal; and (4 ecological factors contributing to the maintenance of RF spirochetes in nature.

  1. Computed tomography of the head of new born premature infants

    International Nuclear Information System (INIS)

    Evaluation of the extracerebral space on CT resulted as follows: The existence of the etracerebral space in the parieto-occipital region (PO-ECS) was physiological findings characteristic to premature infants. Its incidence was higher and the width of the space was greater, in those of premature infants. Generally PO-ECS disappeared around 40 weeks of gestation, while it tended to remaine beyond 40 weeks in premature infants born after less than 30 weeks of pregnancy. The appearance and disappearance of the PO-ECS may present some approach to learning the development of the brain in premature infants. (Ueda, J.)

  2. An Epidemiological Investigation of Male-Female Differences in Drinking and Drinking-Related Problems between US-Born and Foreign-Born Latino and Asian Americans

    Directory of Open Access Journals (Sweden)

    Hui G. Cheng

    2013-01-01

    Full Text Available Background. It has been widely documented that males were more likely to drinking alcohol and have alcohol use disorders (AUD. The degrees of the male-female differences in drinking and AUD have varied across countries. The reasons behind these variations have not been fully understood. The current study compared the estimated male-female differences across US-born and foreign-born Latino and Asian Americans with respect to alcohol drinking behavior and AUD. Method. Data come from the National Latino and Asian American Study (NLAAS, a national household survey of adults with Latinos and Asian decent in the United States. Male-female differences were estimated for drinking behavior and AUD among drinkers for US-born and foreign-born individuals, respectively. Zero-inflated Poisson regressions were utilized to estimate male-female differences in the number of AUD clinical features once it occurs. Results. Larger male-female differences were found for foreign-born individuals as compared to US-born individuals, especially the occurrence of AUD among drinkers. Once AUD clinical feature occurs, there was no male-female difference for foreign-born individuals, while there was a males excess in the number of clinical features for US-born individuals. Conclusion. Results from this study supports the importance of sociocultural influence in drinking and AUD. Implications for prevention and intervention programs were discussed.

  3. Dietary Sodium Intakes and Food Sources of Sodium in Canadian-Born and Asian-Born Individuals of Chinese Ethnicity at a Canadian University Campus

    Science.gov (United States)

    Yu, Yan Han; Farmer, Anna; Mager, Diana; Willows, Noreen

    2014-01-01

    Objective: To document the sodium intake and food sources of sodium of Canadian-born Chinese (CBC) and Asian-born Chinese (ABC) individuals at a Canadian university campus. Participants: Healthy adults aged 18-58 years originating from Canada, China, Hong Kong, or Taiwan were recruited from the University of Alberta (n = 40 CBC, n = 41 ABC)…

  4. Perceptions of Clinical Education Preparedness at a Large Urban US University: Is There a Difference between US-Born and Non-US Born Students?

    Science.gov (United States)

    Cohen, Timmerie; Justice, M. Ferell; Dempsey, Melanie C.

    2014-01-01

    This research compared three clinical preparedness domains, communication ability, social comfort, and clinical confidence, between US-born and non-US born radiation sciences students. The aim of the study was to determine if there were perceived differences in clinical preparedness between them. Student's place of birth was found to be an…

  5. The global aftershock zone

    Science.gov (United States)

    Parsons, Thomas E.; Margaret Segou,; Warner Marzocchi,

    2014-01-01

    The aftershock zone of each large (M ≥ 7) earthquake extends throughout the shallows of planet Earth. Most aftershocks cluster near the mainshock rupture, but earthquakes send out shivers in the form of seismic waves, and these temporary distortions are large enough to trigger other earthquakes at global range. The aftershocks that happen at great distance from their mainshock are often superposed onto already seismically active regions, making them difficult to detect and understand. From a hazard perspective we are concerned that this dynamic process might encourage other high magnitude earthquakes, and wonder if a global alarm state is warranted after every large mainshock. From an earthquake process perspective we are curious about the physics of earthquake triggering across the magnitude spectrum. In this review we build upon past studies that examined the combined global response to mainshocks. Such compilations demonstrate significant rate increases during, and immediately after (~ 45 min) M > 7.0 mainshocks in all tectonic settings and ranges. However, it is difficult to find strong evidence for M > 5 rate increases during the passage of surface waves in combined global catalogs. On the other hand, recently published studies of individual large mainshocks associate M > 5 triggering at global range that is delayed by hours to days after surface wave arrivals. The longer the delay between mainshock and global aftershock, the more difficult it is to establish causation. To address these questions, we review the response to 260 M ≥ 7.0 shallow (Z ≤ 50 km) mainshocks in 21 global regions with local seismograph networks. In this way we can examine the detailed temporal and spatial response, or lack thereof, during passing seismic waves, and over the 24 h period after their passing. We see an array of responses that can involve immediate and widespread seismicity outbreaks, delayed and localized earthquake clusters, to no response at all. About 50% of the

  6. Differing first year mortality rates of term births to White, African-American, and Mexican-American US-born and foreign-born mothers.

    Science.gov (United States)

    Collins, James W; Soskolne, Gayle R; Rankin, Kristin M; Bennett, Amanda C

    2013-12-01

    To determine whether maternal nativity (US-born versus foreign-born) is associated with the first year mortality rates of term births. Stratified and multivariable binomial regression analyses were performed on the 2003-2004 National Center for Health Statistics linked live birth-infant death cohort files. Only term (37-42 weeks) infants with non-Latina White, African-American, and Mexican-American mothers were studied. The infant mortality rate (mortality for non-LBW, term births to US-born (compared to foreign-born) for White, African-American, and Mexican-American mothers equaled 1.5 (1.3-1.7), 1.7 (1.5-2.1) and 1.6 (1.4-1.8), respectively. The IMR of term births to White, African-American, and Mexican-American mothers exceeds that of their counterparts with foreign-born mothers independent of traditional individual level risk factors.

  7. Native-born versus foreign-born patients' perception of communication and care in Swedish dental service.

    Science.gov (United States)

    Olausson, Minh; Esfahani, Nadya; Östlin, Johanna; Hägglin, Catharina

    2016-01-01

    Like many other countries Sweden is becoming more multicultural and many residents do not fully master the national language and are not completely familiar with national norms and habits. The key to good interaction between dentists and patients is communication. Therefore this study aimed to examine whether there are differences in the experience of communication and care between native-born (NB) and foreign-born (FB) patients in the Swedish Public Dental Service (PDS). Consecutive patients at four PDS clinics in a major Swedish city (Gothenburg) were asked to complete the Dental Visit Satisfaction Scale (DVSS), eight additional items concerning communication and care, and a questionnaire eliciting background information.The questionnaires were available in English, Swedish, Arabic and Farsi. The response rate was 74% (204 patients, mean age: 42 years, range 18-86). Of the participants, 96 (47%) were NB and 108 (53%) were FB; 80 (40%) were men and 121 (60%) women. The NB group was significantly older, had higher education and more regular dental care habits, and reported higher dental fear than the FB group. Fewer FB than NB patients thought the dentist treated them in the same manner as he or she would treat other patients and this applied particularly to those who had lived in Sweden for more than 5 years. FB patients were as satisfied with the information and communication they received from the dentist as those born in Sweden, but they were more sceptical about the dentist's technical competence. The differences between the two groups were otherwise smaller than might have been expected in view of probable language difficulties and differences in dental care background. PMID:27464385

  8. The galactic habitable zone of the Milky Way and M31 from chemical evolution models with gas radial flows

    CERN Document Server

    Spitoni, E; Sozzetti, A

    2014-01-01

    The galactic habitable zone is defined as the region with sufficient abundance of heavy elements to form planetary systems in which Earth-like planets could be born and might be capable of sustaining life, after surviving to close supernova explosion events. Galactic chemical evolution models can be useful for studying the galactic habitable zones in different systems. We apply detailed chemical evolution models including radial gas flows to study the galactic habitable zones in our Galaxy and M31. We compare the results to the relative galactic habitable zones found with "classical" (independent ring) models, where no gas inflows were included. For both the Milky Way and Andromeda, the main effect of the gas radial inflows is to enhance the number of stars hosting a habitable planet with respect to the "classical" model results, in the region of maximum probability for this occurrence, relative to the classical model results. These results are obtained by taking into account the supernova destruction process...

  9. White matter and cognition in adults who were born preterm.

    Directory of Open Access Journals (Sweden)

    Matthew P G Allin

    Full Text Available BACKGROUND AND PURPOSE: Individuals born very preterm (before 33 weeks of gestation, VPT are at risk of damage to developing white matter, which may affect later cognition and behaviour. METHODS: We used diffusion tensor MRI (DT-MRI to assess white matter microstructure (fractional anisotropy; FA in 80 VPT and 41 term-born individuals (mean age 19.1 years, range 17-22, and 18.5 years, range 17-22 years, respectively. VPT individuals were part of a 1982-1984 birth cohort which had been followed up since birth; term individuals were recruited by local press advertisement. General intellectual function, executive function and memory were assessed. RESULTS: The VPT group had reduced FA in four clusters, and increased FA in four clusters relative to the Term group, involving several association tracts of both hemispheres. Clusters of increased FA were associated with more severe neonatal brain injury in the VPT group. Clusters of reduced FA were associated with lower birth weight and perinatal hypoxia, and with reduced adult cognitive performance in the VPT group only. CONCLUSIONS: Alterations of white matter microstructure persist into adulthood in VPT individuals and are associated with cognitive function.

  10. Tick-borne infections in human and animal population worldwide

    Directory of Open Access Journals (Sweden)

    José Brites-Neto

    2015-03-01

    Full Text Available The abundance and activity of ectoparasites and its hosts are affected by various abiotic factors, such as climate and other organisms (predators, pathogens and competitors presenting thus multiples forms of association (obligate to facultative, permanent to intermittent and superficial to subcutaneous developed during long co-evolving processes. Ticks are ectoparasites widespread globally and its eco epidemiology are closely related to the environmental conditions. They are obligatory hematophagous ectoparasites and responsible as vectors or reservoirs at the transmission of pathogenic fungi, protozoa, viruses, rickettsia and others bacteria during their feeding process on the hosts. Ticks constitute the second vector group that transmit the major number of pathogens to humans and play a role primary for animals in the process of diseases transmission. Many studies on bioecology of ticks, considering the information related to their population dynamics, to the host and the environment, comes possible the application and efficiency of tick control measures in the prevention programs of vector-borne diseases. In this review were considered some taxonomic, morphological, epidemiological and clinical fundamental aspects related to the tick-borne infections that affect human and animal populations.

  11. On the mathematical treatment of the Born-Oppenheimer approximation

    Energy Technology Data Exchange (ETDEWEB)

    Jecko, Thierry, E-mail: thierry.jecko@u-cergy.fr [AGM, UMR 8088 du CNRS, Université de Cergy-Pontoise, Département de mathématiques, site de Saint Martin, 2 avenue Adolphe Chauvin, F-95000 Pontoise (France)

    2014-05-15

    Motivated by the paper by Sutcliffe and Woolley [“On the quantum theory of molecules,” J. Chem. Phys. 137, 22A544 (2012)], we present the main ideas used by mathematicians to show the accuracy of the Born-Oppenheimer approximation for molecules. Based on mathematical works on this approximation for molecular bound states, in scattering theory, in resonance theory, and for short time evolution, we give an overview of some rigorous results obtained up to now. We also point out the main difficulties mathematicians are trying to overcome and speculate on further developments. The mathematical approach does not fit exactly to the common use of the approximation in Physics and Chemistry. We criticize the latter and comment on the differences, contributing in this way to the discussion on the Born-Oppenheimer approximation initiated by Sutcliffe and Woolley. The paper neither contains mathematical statements nor proofs. Instead, we try to make accessible mathematically rigourous results on the subject to researchers in Quantum Chemistry or Physics.

  12. Why Einstein (Had I been born in 1844!)?

    CERN Document Server

    Dadhich, N

    2005-01-01

    In his monumental discoveries, the driving force for Einstein was, I believe, consistency of concept and principle rather than conflict with experiment. In this spirit, I would like to look at the journey from the classical to the relativistic world as a simple and direct exercise first in recognition of universal character of universal entities and then carrying out the universalization. By this process not only the relativistic world follows most naturally but I would like to conjecture that if Einstein were born in 1844 (or had I been born in 1844 and had followed this line of thought as I do now!) it would have in fact been predicted including existence of a wave with universal constant velocity. That would have indeed been not only the greatest but most amazing and remarkable feat of human thought. Beating further on the same track of principle and concept driven ideas, we ponder over to see beyond Einstein, and ask the questions: in how many dimensions does gravity live, how many basic forces are there ...

  13. Dualities in M-theory and Born-Infeld Theory

    Energy Technology Data Exchange (ETDEWEB)

    Brace, Daniel, M

    2001-08-01

    We discuss two examples of duality. The first arises in the context of toroidal compactification of the discrete light cone quantization of M-theory. In the presence of nontrivial moduli coming from the M-theory three form, it has been conjectured that the system is described by supersymmetric Yang-Mills gauge theory on a noncommutative torus. We are able to provide evidence for this conjecture, by showing that the dualities of this M-theory compactification, which correspond to T-duality in Type IIA string theory, are also dualities of the noncommutative supersymmetric Yang-Mills description. One can also consider this as evidence for the accuracy of the Matrix Theory description of M-theory in this background. The second type of duality is the self-duality of theories with U(1) gauge fields. After discussing the general theory of duality invariance for theories with complex gauge fields, we are able to find a generalization of the well known U(1) Born-Infeld theory that contains any number of gauge fields and which is invariant under the maximal duality group. We then find a supersymmetric extension of our results, and also show that our results can be extended to find Born-Infeld type actions in any even dimensional spacetime.

  14. HOW CAN NEWLY BORN RAPIDLY ROTATING NEUTRON STARS BECOME MAGNETARS?

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Quan; Yu, Yun-Wei, E-mail: yuyw@mail.ccnu.edu.cn [Institute of Astrophysics, Central China Normal University, Wuhan 430079 (China)

    2014-05-10

    In a newly born (high-temperature and Keplerian rotating) neutron star, r-mode instability can lead to stellar differential rotation, which winds the seed poloidal magnetic field (∼10{sup 11} G) to generate an ultra-high (∼10{sup 17} G) toroidal field component. Subsequently, by succumbing to the Tayler instability, the toroidal field could be partially transformed into a new poloidal field. Through such dynamo processes, the newly born neutron star with sufficiently rapid rotation could become a magnetar on a timescale of ∼10{sup 2} {sup –} {sup 3} s, with a surface dipolar magnetic field of ∼10{sup 15} G. Accompanying the field amplification, the star could spin down to a period of ∼5 ms through gravitational wave radiation due to the r-mode instability and, in particular, the non-axisymmetric stellar deformation caused by the toroidal field. This scenario provides a possible explanation for why the remnant neutron stars formed in gamma-ray bursts and superluminous supernovae could be millisecond magnetars.

  15. On the Electrostatic Born-Infeld Equation with Extended Charges

    Science.gov (United States)

    Bonheure, Denis; d'Avenia, Pietro; Pomponio, Alessio

    2016-09-01

    In this paper, we deal with the electrostatic Born-Infeld equation -operatorname{div} (nablaφ/√{1-|nabla φ|^2} )= ρ quad{in} {R}^N, lim_{|x|to ∞} φ(x)= 0,. quad quad quad quad ({{BI}}) where {ρ} is an assigned extended charge density. We are interested in the existence and uniqueness of the potential {φ} and finiteness of the energy of the electrostatic field {-nabla φ}. We first relax the problem and treat it with the direct method of the Calculus of Variations for a broad class of charge densities. Assuming {ρ} is radially distributed, we recover the weak formulation of {({{BI}})} and the regularity of the solution of the Poisson equation (under the same smoothness assumptions). In the case of a locally bounded charge, we also recover the weak formulation without assuming any symmetry. The solution is even classical if {ρ} is smooth. Then we analyze the case where the density {ρ} is a superposition of point charges and discuss the results in (Kiessling, Commun Math Phys 314:509-523, 2012). Other models are discussed, as for instance a system arising from the coupling of the nonlinear Klein-Gordon equation with the Born-Infeld theory.

  16. Observational constraints on electromagnetic Born-Infeld cosmology

    CERN Document Server

    Bretón, Nora; Montiel, Ariadna

    2012-01-01

    The cosmological model consisting of an electromagnetic Born-Infeld (BI) field coupled to a Robertson-Walker geometry is tested with the standard probes of SNIa, GRBs and direct Hubble parameter. The analysis shows that the inclusion of the nonlinear electromagnetic component does not contribute in a significative way to the observed expansion. The BI electromagnetic matter is considered with an abundance of $\\Omega_{BI}$, that our best fit leads to $\\Omega_{BI}=0.037$ when tested with SNIa and the Hubble parameter data (0.1Born-Infeld matter as the origin of ...

  17. THE ROLE OF INTERNET IN THE BORN GLOBAL COMPANIES

    Directory of Open Access Journals (Sweden)

    Marcus Vinicius de Oliveira Brasil

    2013-06-01

    Full Text Available The process of internationalization of global companies occurs connected to the high integration through the nets of computers, especially the Internet. The technological advances have revolutionized the forms of transacting products and services. Innovation becomes the key word for this new phase established in the economy by the computer science in which the Internet is able to establish a larger integration among the enterprises, consumers and suppliers. How can the Internet contribute to the process of Internationalization of Born Globals? This theoretical paper aims to discuss the role of innovations with internet in Born Globals firms to the process of internationalization. The literature review on the subject shows that the advances of technology will require new studies about the internationalization’s process. In spite of that, the influence of the electronic business has progressed in commercial transactions. The global world requires workers who are more and more prepared to face such reality. The enterprises will have to adapt, otherwise they may fail to reduce costs and to improve their logistics. The consumers can have personalized products, while their needs are met in a more comfortable, immediate way and with less intermediates. The electronic markets revolutionize the economy by meeting old needs in a more modern and practical way.

  18. Stability of a tick-borne flavivirus in milk

    Directory of Open Access Journals (Sweden)

    Danielle K Offerdahl

    2016-05-01

    Full Text Available The tick-borne flaviviruses (TBFV occur worldwide and the tick-borne encephalitis virus members of the group (TBEV often cause severe, debilitating neurological disease in humans. Although the primary route of infection is through the bite of an infected tick, alimentary infection through the consumption of TBEV-contaminated dairy products is also well-documented and is responsible for some disease in endemic areas. Experimental infection of goats, cattle, and sheep with TBEV shows that virus can be excreted in the milk of infected animals. Additionally, the virus remains infectious after exposure to low pH levels, similar to those found in the stomach. To evaluate survival of virus in milk, we studied the stability of the BSL-2 TBFV, Langat virus, in unpasteurized goat milk over time and after different thermal treatments. Virus was stable in milk maintained under refrigeration conditions; however, there was a marked reduction in virus titer after incubation at room temperature. High temperature, short time pasteurization protocols completely inactivated the virus. Interestingly, simulation of a typical thermal regime utilized for cheese did not completely inactivate the virus in milk. These findings stress the importance of proper milk handling and pasteurization processes in areas endemic for TBEV.

  19. Born in Bradford, a cohort study of babies born in Bradford, and their parents: Protocol for the recruitment phase

    Directory of Open Access Journals (Sweden)

    Raynor Pauline

    2008-09-01

    Full Text Available Abstract Background Bradford, one of the most deprived cities in the United Kingdom, has a wide range of public health problems associated with socioeconomic deprivation, including an infant mortality rate almost double that for England and Wales. Infant mortality is highest for babies of Pakistani origin, who comprise almost half the babies born in Bradford. The Born in Bradford cohort study aims to examine environmental, psychological and genetic factors that impact on health and development perinatally, during childhood and subsequent adult life, and those that influence their parents' health and wellbeing. This protocol outlines methods for the recruitment phase of the study. Methods Most Bradford women attend for antenatal care and give birth at the Bradford Royal Infirmary, which has approximately 5,800 births per year. Women are eligible for recruitment if they plan to give birth here. Babies born from March 2007 are eligible to participate, recruitment is planned to continue until 2010. Fathers of babies recruited are invited to participate. Women are usually recruited when they attend for a routine oral glucose tolerance test at 26–28 weeks gestation. Recruitment of babies is at birth. Fathers are recruited whenever possible during the antenatal period, or soon after the birth. The aim is to recruit 10,000 women, their babies, and the babies' fathers. At recruitment women have blood samples taken, are interviewed to complete a semi-structured questionnaire, weighed, and have height, arm circumference and triceps skinfold measured. Umbilical cord blood is collected at birth. Within two weeks of birth babies have their head, arm and abdominal circumference measured, along with subscapular and triceps skinfold thickness. Fathers self-complete a questionnaire at recruitment, have height and weight measured, and provide a saliva sample. Participants are allocated a unique study number. NHS numbers will be used to facilitate record linkage

  20. Childbearing characteristics of U.S.- and foreign-born Hispanic mothers.

    Science.gov (United States)

    Ventura, S J; Taffel, S M

    1985-01-01

    This study compares maternal and infant health and sociodemographic characteristics of U.S.-born and foreign- or Puerto Rican-born Hispanic mothers and their babies, using data from the national vital statistics system and the 1980 National Natality Survey. While nearly half of all Hispanic mothers and Mexican and Puerto Rican mothers were born in the United States, less than 10 percent of Cuban and other Hispanic mothers were U.S. born. Compared with foreign- or Puerto Rican-born Hispanic mothers, U.S.-born mothers tended to be younger, to have had fewer high-order births, to be less likely to receive delayed or no prenatal care, to have higher educational attainment, and to be more likely to be unmarried. The incidence of low birth weight among infants born to Hispanic mothers, particularly Mexican and Cuban women, was relatively low. When the proportions of low birth weight were examined by nativity status, infants born to foreign- or Puerto Rican-born women were consistently less likely to be of low birth weight. In an effort to account for these findings, the mother's smoking status before and during pregnancy is examined. Compared with non-Hispanic mothers, Hispanic mothers were much less likely to have smoked before or during pregnancy. These data are examined to see if they account for the better outcome as measured by birth weight for Hispanic births, especially those to foreign- or Puerto Rican-born women.

  1. Circulation pumps as structure-borne sound sources: emission to semi-infinite pipe systems

    Science.gov (United States)

    Qi, N.; Gibbs, B. M.

    2003-06-01

    Circulation pumps are an important source of noise from domestic central heating systems. Pumps can generate airborne, liquid-borne and structure-borne sound and although standards exist for airborne and liquid-borne sources, none do for structure-borne sources. This is primarily because the structure-borne acoustic power delivered by the pump not only depends on the pump but also on the connected receiving system, which can be a complicated combination of pipes, valves and radiators. Also pumps deliver liquid-borne and structure-borne acoustic power simultaneously and their relative contributions to the sound radiated from the pipe system is not obviously obtainable. The approach proposed is to estimate the emission from the pump into semi-infinite pipes of material and cross-section typical of heating systems. Then to estimate the 'mixing' effect of bends, joints and other pipe discontinuities, due to wave mode conversion, as described in a companion paper. In the present paper, it is demonstrated that the structure-borne power can be calculated from the measured free velocity and mobility of the pump for each component of vibration and from receiver mobilities of idealized pipe systems. The structure-borne power is compared with the liquid-borne power measured directly by intensimetry.

  2. Content and the forms of heavy metals in bottom sediments in the zone of industrial pollution sources ,

    OpenAIRE

    Voytyuk Y.Y.; Kurayeva I.V.; Kroyik H.A.; Karmazynenko S.P.; Matsibora O.V.

    2014-01-01

    Regularities in the distribution of heavy metals in sediments in the zone of influence of the steel industry in Mariupol are installed. The study results of the forms of occurrence of Zn, Pb, Cu, Cr, Ni are represented. Ecological and geochemical assessment of sediment contamination by heavy metals is performed. The main sources of pollution of bottom sediments are air borne emissions from industrial plants, hydrogenous pollution in industrial sewage entering the water, sewage sludge, ash dum...

  3. Zone and double zone diagrams in abstract spaces

    CERN Document Server

    Reem, Daniel

    2007-01-01

    A zone diagram of order $n$ is a relatively new concept which was first defined and studied by T. Asano, J. Matousek and T. Tokuyama. It can be interpreted as a state of equilibrium between $n$ mutually hostile kingdoms. Formally, it is a fixed point of a certain mapping. These authors considered the Euclidean plane and proved the existence and uniqueness of zone diagrams there. In the present paper we generalize this concept in various ways. We consider $m$-spaces (a simple generalization of metric spaces) and prove some existence and (non)uniqueness results there. In contrast to previous works, our proofs are based on purely order theoretic arguments. Many explicit examples are given, and some of them illustrate new phenomena which occur in the general case. We also re-interpret zone diagrams as a stable configuration in a certain combinatorial game, and provide an algorithm for finding this configuration in a particular case.

  4. Problems of Chernobyl exclusion zone

    International Nuclear Information System (INIS)

    The collection comprises the results of researches and design activity in the ChNPP exclusion zone with the aim to develop technology, equipment and instruments for RAW management and accident clean-up, studying of the composition and structure of the activity solid bearers in the soil of the exclusion zone and transformation of the radionuclides in the nearest zone of ChNPP. Much attention is paid to medical and biological problems of the accident influence on the flora, fauna and people's health, labour conditions and incidence of the people involved. The collection comprises the information for scientists, experts, postgraduates and students in gaged in ecology, radioecology, nuclear engineering, radiology, radiochemistry and radiobiology

  5. Born modeling for heterogeneous media using the Gaussian beam summation based Green's function

    Science.gov (United States)

    Huang, Xingguo; Sun, Hui; Sun, Jianguo

    2016-08-01

    Born approximation is a commonly used approximation in the simulation of seismic wave propagation. Calculation of the Green's function in Born approximation integral is essential for Born modeling. We derive a new Born formula based on the Gaussian beam representations of Green's functions. This procedure can be used to mitigate the problems like the caustic, shadow region, and multivalued traveltime caused by multipathing that traditional geometric ray theory cannot deal with. However, due to the characteristic of complex traveltime in the Gaussian beam, we present a new isochronous stack method for Gaussian beam based Born modeling. Additionally, two basic issues, background velocity and integral region selection, are discussed. Numerical results demonstrate the accuracy and efficiency of the Gaussian beam based Born theory and implementation.

  6. International Network for Capacity Building for the Control of Emerging Viral Vector-Borne Zoonotic Diseases: Arbo-Zoonet

    OpenAIRE

    Ahmed, J.; Bouloy, M.; Ergonul, O.; Fooks, A. R.; Paweska, J.; Chevalier, V.; Drosten, C.; Moormann, R. J. M.; Tordo, N.; Vatansever, Z.; Calistri, P.; Estrada-Pena, A.; Mirazimi, A; Unger, H; Yin, H.

    2009-01-01

    Arboviruses are arthropod-borne viruses, which include West Nile fever virus (WNFV), a mosquito-borne virus, Rift Valley fever virus (RVFV), a mosquito-borne virus, and Crimean-Congo haemorrhagic fever virus (CCHFV), a tick-borne virus. These arthropod-borne viruses can cause disease in different domestic and wild animals and in humans, posing a threat to public health because of their epidemic and zoonotic potential. In recent decades, the geographical distribution of these diseases has expa...

  7. Earthquake Zoning Maps of Turkey

    International Nuclear Information System (INIS)

    Earthquake Zoning Maps (1945, 1947, 1963, 1972 and 1996) and Specifications for Construction in Disaster Areas (1947, 1953, 1962, 1968, 1975, 1996, 1997 and 2006) have been changed many times following the developments in engineering seismology, tectonic and seismo-tectonic invention and improved earthquake data collection. The aim of this study is to give information about this maps, which come into force at different dates since the introduction of the firs official Earthquake Zoning Map published in 1945 and is to assist for better understanding of the development phases of these maps

  8. Staphylococcus aureus and Staphylococcal Food-Borne Disease: An Ongoing Challenge in Public Health

    OpenAIRE

    Jhalka Kadariya; Smith, Tara C.; Dipendra Thapaliya

    2014-01-01

    Staphylococcal food-borne disease (SFD) is one of the most common food-borne diseases worldwide resulting from the contamination of food by preformed S. aureus enterotoxins. It is one of the most common causes of reported food-borne diseases in the United States. Although several Staphylococcal enterotoxins (SEs) have been identified, SEA, a highly heat-stable SE, is the most common cause of SFD worldwide. Outbreak investigations have found that improper food handling practices in the retail ...

  9. Immigrant Latino neighborhoods and mortality among infants born to Mexican-origin Latina women.

    Science.gov (United States)

    DeCamp, Lisa Ross; Choi, Hwajung; Fuentes-Afflick, Elena; Sastry, Narayan

    2015-06-01

    To compare the association between neighborhood Latino immigrant concentration and infant mortality by maternal nativity among singleton births to Mexican-origin women in Los Angeles County. Information about births, infant deaths, and infant and maternal characteristics were obtained from geocoded Los Angeles County vital statistics records (2002-2005). Linked data on neighborhood characteristics (census tracts) were obtained from the 2000 census. Logistic regression models were used to predict infant mortality while accounting for spatial clustering by census tract. Two-thirds of births to Mexican-origin mothers were to foreign-born women. Foreign-born mothers were older, had less education, and were more likely to have delivery costs paid by Medicaid than US-born mothers. Infants born to foreign-born women had a lower infant mortality rates than infants born to US-born women (3.8/1,000 live births vs. 4.6, p = .002). Among infants of foreign-born mothers, the odds of infant mortality increased with increasing immigrant concentration (OR 1.29; 95 % CI 1.01-1.66). There was a similar pattern of association between immigrant concentration and mortality for infants of US-born mothers (OR 1.29; 95 % CI 0.99-1.67). In Los Angeles County, the odds of infant mortality among foreign-born Mexican-origin Latina were higher in higher-density immigrant neighborhoods, with a similar trend among US-born mothers. Thus, living in immigrant enclaves likely does not help to explain the lower than expected infant mortality rate among infants born to Latina women. Instead, higher neighborhood Latino immigrant concentration may indicate a neighborhood with characteristics that negatively impact maternal and infant health for Latinos.

  10. Growth phases and survival of born globals - Case: Finnish software firms

    OpenAIRE

    Hashimoto, Shiho

    2011-01-01

    Objectives of the Research This study was part of the “Born Global Growth and Survival” joint project by Aalto University School of Economics and University of Vaasa. Based on a literature review and an empirical research, the growth phases of Born Global firms and factors that influence the growth and survival of these firms are introduced. This particular thesis contributes by focusing specifically on the Born Global firms in the software business. The literature review covers such t...

  11. Ecommerce drivers and marketing partnerships in successful export marketing of Finnish born globals

    OpenAIRE

    Penttinen, Jukka

    2015-01-01

    This study examines the utilization of ecommerce and marketing partnerships as part of born global internationalization strategies. The study will combine the existing literature of born global internationalization, export marketing strategies and ecommerce as part of internationalization to form an understanding on how two Finnish health and welfare sector born globals internationalize, and how ecommerce drivers affect their internationalization. Because of the explorative nature of the stud...

  12. Globalization of Finnish ICT Born Globals: Creating new market space with disruptive innovation strategy

    OpenAIRE

    Myllymäki, Arttu

    2010-01-01

    ABSTRACT Objective Objective of this Master’s thesis is to research Finnish ICT Born Global companies that have globalized their operations leveraging disruptive technologies and how disruptive innovation influences the globalization? This topic has become increasingly relevant as many Born Globals do in fact, leverage disruptive innovation as a strategic approach. However, Born Global theory has not really been approached previously from the this type of value innovation perspective ...

  13. Eddington-Born-Infeld action for dark energy and dark matter

    OpenAIRE

    Banados, Maximo

    2008-01-01

    We argue that Einstein gravity coupled to a Born-Infeld theory provides an attractive candidate to represent dark matter and dark energy. For cosmological models, the Born-Infeld field has an equation of state which interpolates between matter, w=0 (small times), and a cosmological constant w=-1 (large times). On galactic scales, the Born-Infeld field predicts asymptotically flat rotation curves.

  14. Prototype TIGRE Compton γ-ray balloon-borne telescope

    Science.gov (United States)

    Bhattacharya, D.; O'Neill, T. J.; Akyüz, A.; Samimi, J.; Zych, A. D.

    2004-02-01

    A prototype balloon-borne telescope is being constructed for γ-ray observations in the MeV energy range. The Tracking and Imaging Gamma-Ray Experiment (TIGRE) uses multi-layers of thin silicon detectors to track and measure the energy losses of Compton recoil electrons. When combined with the direction and energy of the Compton scattered γ-ray a unique incident direction for each photon event is determined. This facilitates background rejection, improved sensitivity and image reconstruction. The converter/tracker also serves as an electron-positron pair detector for γ-rays up to 100 MeV. The initial continental US flight will be used to determine the sub-orbital atmospheric backgrounds and search for polarized γ-emission for the Crab pulsar. Longer southern hemisphere flights with an enhanced instrument will map out the 26Al emissions from the galactic center region.

  15. Feeding considerations in infants born with cleft lip and palate

    Directory of Open Access Journals (Sweden)

    M Subramanya Shetty

    2016-01-01

    Full Text Available Infants born with the congenital deformity of cleft lip and or palate suffer from varieties of complications since the day 1 of their life. The most important of which is the feeding difficulty which leads to insufficient food intake and thereby causing deleterious effects on their overall development leading to malnutrition and death in some cases. However, research into the anatomical variations of these infants in the region of lip and palate has led to the development of several types of feeders and their modifications which would help them thrive well in the initial days and also for later. Hence, it is worth important to know about them in detail and help these infants and their families psychologically so that the infants do not suffer from feeding difficulties anymore.

  16. Major congenital anomalies in babies born with Down syndrome

    DEFF Research Database (Denmark)

    Morris, Joan K; Garne, Ester; Wellesley, Diana;

    2014-01-01

    Previous studies have shown that over 40% of babies with Down syndrome have a major cardiac anomaly and are more likely to have other major congenital anomalies. Since 2000, many countries in Europe have introduced national antenatal screening programs for Down syndrome. This study aimed...... to determine if the introduction of these screening programs and the subsequent termination of prenatally detected pregnancies were associated with any decline in the prevalence of additional anomalies in babies born with Down syndrome. The study sample consisted of 7,044 live births and fetal deaths with Down...... syndrome registered in 28 European population-based congenital anomaly registries covering seven million births during 2000-2010. Overall, 43.6% (95% CI: 42.4-44.7%) of births with Down syndrome had a cardiac anomaly and 15.0% (14.2-15.8%) had a non-cardiac anomaly. Female babies with Down syndrome were...

  17. c-Map for Born-Infeld theories

    Science.gov (United States)

    Andrianopoli, L.; D'Auria, R.; Ferrara, S.; Trigiante, M.

    2016-07-01

    The c-map of four dimensional non-linear theories of electromagnetism is considered both in the rigid case and in its coupling to gravity. In this way theories with antisymmetric tensors and scalars are obtained, and the three non-linear representations of N = 2 supersymmetry partially broken to N = 1 related. The manifest Sp (2 n) and U (n) covariance of these theories in their multifield extensions is also exhibited. This construction extends to H-invariant non-linear theories of Born-Infeld type with non-dynamical scalars spanning a symmetric coset manifold G/H and the vector field strengths and their duals in a symplectic representation of G as is the case for extended supergravity.

  18. Born Global Firms: A Foreign Trade Related Study on Turkey

    Directory of Open Access Journals (Sweden)

    Aytaç GÖKMEN

    2013-11-01

    Full Text Available With the comprehensive advent in information and communication technologies and worldwide ease of transportation, the volume of international trade and business increased profoundly. Within this process, a Born Global Firm (BGF, right from its initiation, aims at creating competitive advantage by marketing a large volume of its products in various international markets by utilizing technological advances. Therefore, the rational behind the idea of BGF is to become an international firm in a short period of time and making international business affairs core of its business activities. Thus, the aim of this study is to review the concept of BGF theoretically and relate the issue to foreign trade affairs resting on significant sources related to the Turkish case mainly focusing on trade statistics as to review the potential development of BGFs in Turkey.

  19. Mycobacterium bovis meningitis in young Nigerian-born male

    DEFF Research Database (Denmark)

    Faurholt-Jepsen, Daniel; Lillebæk, Troels; Nielsen, Ming-Yuan;

    2014-01-01

    In Denmark, tuberculous meningitis is rare. Central nervous system (CNS) involvement with Mycobacterium bovis is even rarer and has only been seen three times since 1992. We present a case of M. bovis meningitis in a previously healthy young Nigerian-born male, who had been exposed to unpasteurized...... dairy products in Nigeria but had no known contact with larger mammals. Before the development of meningitis, the patient had several contacts with the health system due to fever and non-specific symptoms. Finally, upon hospital admission, the patient was diagnosed with M. tuberculosis complex...... meningitis and treated empirically. After 13 days he was discharged without neurological sequelae. Later, the culture revealed M. bovis and treatment was adjusted accordingly....

  20. Born-infeld electrodynamics: Clifford number and spinor representations

    Directory of Open Access Journals (Sweden)

    Alexander A. Chernitskii

    2002-01-01

    Full Text Available The Clifford number formalism for Maxwell equations is considered. The Clifford imaginary unit for space-time is introduced as coordinate independent form of fully antisymmetric fourth-rank tensor. The representation of Maxwell equations in massless Dirac equation form is considered; we also consider two approaches to the invariance of Dirac equation with respect to the Lorentz transformations. According to the first approach, the unknown column is invariant and according to the second approach it has the transformation properties known as spinorial ones. The Clifford number representation for nonlinear electrodynamics equations is obtained. From this representation, we obtain the nonlinear like Dirac equation which is the form of nonlinear electrodynamics equations. As a special case we have the appropriate representations for Born-Infeld nonlinear electrodynamics.

  1. Brane Death and Dynamics From the Born-Infeld Action

    CERN Document Server

    Callan, C G; Callan, Curtis G.

    1998-01-01

    We use the abelian Born-Infeld action for the worldvolume gauge field and transverse displacement scalars to explore new aspects of D-brane structure and dynamics. We study several classic gauge field configurations, including point charges in any worldvolume dimension and vortices in two worldvolume dimensions, and show that, with an appropriate excitation of the transverse coordinate field, they are BPS-saturated solutions. The Coulomb point charge solutions turn out to represent, with considerable fidelity, fundamental strings attached to the brane (their magnetic counterparts describe D1-branes attached to D3-branes). We also study dynamic issues. First, we show that S-matrix for small excitations propagating on the point charge solution is consistent with (and gives further illuminating information about) Polchinski's effective open string boundary condition. Second, we show that the worldvolume action has Euclidean bounce solutions which describe the decay of widely-separated brane-antibrane pairs via t...

  2. Behavioral and social development of children born extremely premature

    DEFF Research Database (Denmark)

    Esbjørn, Barbara Hoff; Hansen, Bo Mølholm; Munck, Hanne;

    2004-01-01

    A cohort of extremely prematurely born children and matched term controls was assessed at 5 years of age. The parents completed a questionnaire on their behavioral and social development. The purpose was to illuminate whether the children's general intellectual ability and parental sensitivity were...... associated with behavioral and social development. The index children exhibited more hyperactive behavior and had poorer social skills than the controls. Lower Full Scale IQ (FSIQ) was associated with outward reacting and hyperactive behavior and poorer social skills. Sensitive parenting was associated...... with less outward reacting and less hyperactive behavior. When controlling for differences in FSIQ and parental sensitivity, the index children persisted to have an increased risk of exhibiting hyperactive behavior but not poorer social skills. The index children with normal intellectual development...

  3. The virial theorem in Eddington-Born-Infeld gravity

    CERN Document Server

    Santos, Noelia S

    2015-01-01

    We examine the possibility that the Eddington-Born-Infeld (EBI) modified gravity provides an alternative explanation for the mass discrepancy in clusters of galaxies. For this purpose we derive the modified Einstein field equations, finding an additional "geometrical mass" term which provides an effective contribution to the gravitational binding energy. Using some approximations and assumptions for week gravitational fields, and taking into account the collisionless relativistic Boltzmann equation, we derive a generalized version of the virial theorem in the framework of EBI gravity. We show that the "geometrical mass" term may account for the well known virial mass discrepancy in clusters of galaxies. We also derive the velocity dispersion relation for galaxies in the clusters, which could provide an efficient method for testing EBI gravity from astrophysical observations.

  4. The virial theorem in Eddington-Born-Infeld gravity

    Science.gov (United States)

    Santos, Noelia S.; Santos, Janilo

    2015-12-01

    We consider the possibility that the Eddington-Born-Infeld (EBI) modified gravity provides an alternative explanation for the mass discrepancy in clusters of galaxies. For this purpose we derive the modified Einstein field equations, finding an additional "geometrical mass" term which provides an effective contribution to the gravitational binding energy. Using some approximations and assumptions for weak gravitational fields, and taking into account the collisionless relativistic Boltzmann equation, we derive a generalized version of the virial theorem in the framework of EBI gravity. We show that the "geometrical mass" term may account for the well known virial mass discrepancy in clusters of galaxies. We also derive the velocity dispersion relation for galaxies in the clusters, which could provide an efficient method for testing EBI gravity from astrophysical observations.

  5. Plastic Foam Porosity Characterization by Air-Borne Ultrasound

    Science.gov (United States)

    Hoffrén, H.; Karppinen, T.; Hæggström, E.

    2006-03-01

    We continue to develop an ultrasonic burst-reflection method for estimating porosity and tortuosity of solid materials. As a first step we report on method design considerations and measurements on polyurethane foams (Sylomer® vibration dampener) with well-defined porosity. The ultrasonic method is experimentally tested by measuring 235 kHz and 600 kHz air-borne ultrasound reflection from a foam surface at two incidence angles. The reflected sound wave from different foam samples (32% - 64% porosity) was compared to a wave that had traveled from the transmitter to the detector without reflection. The ultrasonically estimated sample porosities coincided within 8% with the porosity estimates obtained by a gravimetric reference method. This parallels the uncertainty of the gravimetric method, 8%. The repeatability of the ultrasonic porosity measurements was better than 5%.

  6. Babies born dying: just bad karma? A discussion paper.

    Science.gov (United States)

    Kain, Victoria J

    2014-12-01

    The paper examines the notion of being born dying and karma. Karma is a belief upheld by Buddhists and non-Buddhists: That is, karma follows people from their previous lives into their current lives. This raises a difficult question: Does karma mean that a baby's death is its own fault? While great peace can be found from a belief in karma, the notion of a baby's karma returning in some sort of retributive, universal justice can be de-emphasized and is considered "un-Buddhist." Having an understanding of karma is intrinsic to the spiritual care for the dying baby, not only from the perspective of parents and families who have these beliefs, but also for reconciling one's own beliefs as a healthcare practitioner.

  7. Can Nitrous Oxide be Measured Using Space Borne Ultraviolet Spectrometers?

    Science.gov (United States)

    Gonzalez Abad, G.; Wang, S.; García Nieto, D.; Benavent Oltra, N.; Anguas Ballesteros, M.; Serranía Alarcón, F.

    2015-12-01

    The photolysis of nitrous oxide (HONO) by longwave UV radiation has hydroxyl radicals (OH) and nitric oxide (NO) as products. Since HONO accumulates in the troposphere during the night hours it plays a major role in the production of OH in the early morning during the wake-up tropospheric photochemistry. Therefore HONO concentrations have strong implications for the formation of ozone (O3) and peroxyacyl nitrates (PANs) in the early hours of the morning. Given the diurnal variation of HONO concentration, measurements from space borne ultraviolet spectrometers have been unsuccessful. The upcoming geostationary instruments devoted to monitor air quality, including TEMPO, will open possibilities to systematically make early morning measurements of HONO. Here we present an observation experiment to analyze the feasibility of HONO measurements from geostationary instruments using a combination of chemical transport models, in situ DOAS measurements of HONO in Madrid and radiative transfer calculations.

  8. Millisecond newly born pulsars as efficient accelerators of electrons

    CERN Document Server

    Osmanov, Z; Machabeli, G; Chkheidze, N

    2015-01-01

    The newly born millisecond pulsars are investigated as possible energy sources for creating ultra-high energy electrons. The transfer of energy from the star rotation to high energy electrons takes place through the Landau damping of centrifugally driven (via a two stream instability) electrostatic Langmuir waves. Generated in the bulk magnetosphere plasma, such waves grow to high amplitudes, and then damp, very effectively, on relativistic electrons driving them to even higher energies. We show that the rate of transfer of energy is so efficient that no energy losses might affect the mechanism of particle acceleration; the electrons might achieve energies of the order of 10^{18}eV for parameters characteristic of a young star.

  9. [Extremely prematurely born children's and their parents' need for support

    DEFF Research Database (Denmark)

    Esbjorn, B.H.; Madsen, B.M.; Munck, H.;

    2008-01-01

    on the basis of a psychological understanding of loss and grief. RESULTS: During the first year of life, index children were more ill and were cared for in the home for a longer time than were reference children. From the 3rd year of life, differences in illness were minimal. Index parents received more....... After discharge, index parents had an increased need of support that could not be fulfilled by family/friends. An understanding hereof may be found in the vulnerability of the children and in a psychological understanding of loss and grief. The parents lacked contact and dialogue with other parents......INTRODUCTION: During the 1990s, knowledge on the psychosocial consequences of extremely preterm birth was requested. The Danish Paediatric Society therefore launched a prospective longitudinal study of all children born in Denmark in 1994-95 with a gestational age of

  10. Non-Born-Oppenheimer calculations of the BH molecule.

    Science.gov (United States)

    Bubin, Sergiy; Stanke, Monika; Adamowicz, Ludwik

    2009-07-28

    Variational calculations employing explicitly correlated Gaussian basis functions have been performed for the ground state of the boron monohydride molecule (BH) and for the boron atom (B). Up to 2000 Gaussians were used for each system. The calculations did not assume the Born-Oppenheimer (BO) approximation. In the optimization of the wave function, we employed the analytical energy gradient with respect to the Gaussian exponential parameters. In addition to the total nonrelativistic energies, we computed scalar relativistic corrections (mass-velocity and Darwin). With those added to the total energies, we estimated the dissociation energy of BH. The non-BO wave functions were also used to compute some expectation values involving operators dependent on the interparticle distances. PMID:19655858

  11. Nordic climate change: data for modeling vector borne diseases

    DEFF Research Database (Denmark)

    Kristensen, Birgit; Bødker, Rene

    spatial parameters relevant to the distribution of vectors were included in the database and used as input in various distribution models. All collected datasets were assembled in a gridded climate database and presented at the website, www.nordrisk.dk. The website was created with the purpose...... interpolated to daily climate surfaces, using a squared IDW method. In the absence of a more local lapse rate the generally accepted lapse rate of -0.006 C˚/m was used to account for the relationship between temperature and altitude. The interpolation was carried out on temperatures at sea...... derivatives were calculated in order to assess the geographical and seasonal variation in the area. In order to evaluate the response of vector borne diseases to possible future climate changes and the subsequent potential spread into new areas, daily temperature predictions (mean, min and max) for three 20...

  12. Robot-borne fault tolerant calculators for nuclear use

    International Nuclear Information System (INIS)

    The use of robots has become a necessity in civil nuclear industry. Electronic systems of such robots must tolerate cumulative ionizing radiation dose effects. Today's objective is to reach a 3 kGy dose resistance. Difficulties and costs involved during on-site maintenance imply to warrant at least one functioning mode in the case of system failure. To improve the behaviour of robot-borne systems, the CEA Department for Nuclear Engineering Studies (DEIN) has developed a method for the selection of industrial electronic components and has built computer architectures which allows to break free from some cumulative dose sensitive parameters. This paper presents the MICADO and CADMOS architectures developed at the DEIN. (J.S.). 15 refs., 5 figs

  13. Profile of tuberculosis among the foreign-born population in Japan, 2007–2014

    Science.gov (United States)

    Uchimura, Kazuhiro; Izumi, Kiyohiko; Ohkado, Akihiro; Ishikawa, Nobukatsu

    2016-01-01

    The proportion of foreign-born people among the newly notified tuberculosis (TB) patients has been increasing in recent years and potentially poses a new challenge to TB control in Japan. In this report, we analysed the data from the Japan TB surveillance system between 2007 and 2014 to gain an overview of the trends and characteristics of foreign-born TB patients in Japan. We found that the proportion of foreign-born TB patients was especially high among the younger age groups – 44.1% among the 20–29 years age group in 2014. The largest groups of foreign-born patients were from China and the Philippines; however, the number of those from Nepal and Viet Nam was on the rise. Students comprised the second largest professional category group for TB after regular workers, and its proportion increased over the study period. Compared to Japan-born TB patients, foreign-born patients were more likely to be diagnosed through routine medical check-ups. Treatment successes and patients still on treatment were significantly lower among foreign-born patients than their Japan-born counterparts; and transferred-out and unknown outcomes were higher. Our results indicated that distinctive subgroups within the foreign-born population in Japan, especially students and regular workers, might have a higher risk of developing TB. Measures to ensure early diagnosis and treatment adherence should be adapted to such populations. PMID:27508086

  14. Arthropod-Borne Diseases: The Camper's Uninvited Guests.

    Science.gov (United States)

    Juckett, Gregory

    2015-08-01

    Arthropod-borne diseases are a major problem whenever outdoor activities bring arthropods and people into contact. The arthropods discussed here include arachnids (ticks) and insects. Most arthropod bites and stings are minor, with the notable exception being bee-sting anaphylaxis. Ticks cause the most disease transmission. Key hard tick vectors include black-legged (Ixodes), dog (Dermacentor), and lone star (Amblyomma) ticks, which transmit Lyme and various rickettsial diseases. Insect repellents, permethrin sprays, and proper tick inspection reduce this risk significantly. Lyme disease and the milder southern-tick-associated rash illness (STARI) are characterized by the erythema migrans rash followed, in the case of Lyme disease, by early, disseminated, and late systemic symptoms. Treatment is with doxycycline or ceftriaxone. Indefinite treatment of "chronic Lyme disease" based on subjective symptoms is not beneficial. Rickettsial diseases include ehrlichiosis, anaplasmosis, and Rocky Mountain spotted fever, which are characterized by fever, headache, and possible rash and should be empirically treated with doxycycline while awaiting laboratory confirmation. Tularemia is a bacterial disease (Francisella) spread by ticks and rabbits and characterized by fever and adenopathy. Treatment is with gentamicin or streptomycin. Babesiosis is a protozoal disease, mimicking malaria, that causes a self-limited flu-like disease in healthy hosts but can be life threatening with immune compromise. Treatment is with atovaquone and azithromycin. Other tick-related conditions include viral diseases (Powassan, Colorado tick fever, heartland virus), tick-borne relapsing fever (Borrelia), and tick paralysis (toxin). Mosquitoes, lice, fleas, and mites are notable for their annoying bites but are increasingly significant disease vectors even in the United States.

  15. Epidemiology and control of malaria and other arthropod born diseases

    Directory of Open Access Journals (Sweden)

    F. J. López-Antuñano

    1992-01-01

    Full Text Available Malaria and other arthropod born diseases remain a serious public health problem affecting the lives and health of certain social groups when the two basic strategies to control fail due to : (1 the lack of effective chemoprophylaxis/chemotherapy or the rapid development of drug resistance of the infectious agents and (2 the ineffectiveness of pesticides or the arthropod vectors develop resistance to them. These situations enhances the need for the design and implementation of other alternatives for sustainable health programmes. The application of the epidemiological methods is essential not only for analyzing the relevant data for the understanding of the biological characteristics of the infectious agents, their reservoirs and vectors and the methods for their control, but also for the assessment of the human behaviour, the environmental, social and economic factors involved in disease transmission and the capacity of the health systems to implement interventions for both changes in human behaviour and environmental management to purpose guaranteed prevention and control of malaria and other arthropod born diseases with efficiency, efficacy and equity. This paper discuss the evolution of the malaria arthropod diseases programmes in the American Region and the perspectives for their integration into health promotion programs and emphasis is made in the need to establish solid basis in the decision-making process for the selection of intervention strategies to remove the risk factors determining the probability to get sick or die from ABDs. The implications of the general planning and the polices to be adopted in an area should be analyzed in the light of programme feasibility at the local level, in the multisectoral context specific social groups and taking in consideration the principles of stratification and equity

  16. Balloon-Borne Infrasound Detection of Energetic Bolide Events

    Science.gov (United States)

    Young, Eliot F.; Ballard, Courtney; Klein, Viliam; Bowman, Daniel; Boslough, Mark

    2016-10-01

    Infrasound is usually defined as sound waves below 20 Hz, the nominal limit of human hearing. Infrasound waves propagate over vast distances through the Earth's atmosphere: the CTBTO (Comprehensive Nuclear-Test-Ban Treaty Organization) has 48 installed infrasound-sensing stations around the world to detect nuclear detonations and other disturbances. In February 2013, several CTBTO infrasound stations detected infrasound signals from a large bolide that exploded over Chelyabinsk, Russia. Some stations recorded signals that had circumnavigated the Earth, over a day after the original event. The goal of this project is to improve upon the sensitivity of the CTBTO network by putting microphones on small, long-duration super-pressure balloons, with the overarching goal of studying the small end of the NEO population by using the Earth's atmosphere as a witness plate.A balloon-borne infrasound sensor is expected to have two advantages over ground-based stations: a lack of wind noise and a concentration of infrasound energy in the "stratospheric duct" between roughly 5 - 50 km altitude. To test these advantages, we have built a small balloon payload with five calibrated microphones. We plan to fly this payload on a NASA high-altitude balloon from Ft Sumner, NM in August 2016. We have arranged for three large explosions to take place in Socorro, NM while the balloon is aloft to assess the sensitivity of balloon-borne vs. ground-based infrasound sensors. We will report on the results from this test flight and the prospects for detecting/characterizing small bolides in the stratosphere.

  17. CHAOTIC ZONES AROUND GRAVITATING BINARIES

    Energy Technology Data Exchange (ETDEWEB)

    Shevchenko, Ivan I., E-mail: iis@gao.spb.ru [Pulkovo Observatory of the Russian Academy of Sciences, Pulkovskoje ave. 65, St. Petersburg 196140 (Russian Federation)

    2015-01-20

    The extent of the continuous zone of chaotic orbits of a small-mass tertiary around a system of two gravitationally bound primaries of comparable masses (a binary star, a binary black hole, a binary asteroid, etc.) is estimated analytically, as a function of the tertiary's orbital eccentricity. The separatrix map theory is used to demonstrate that the central continuous chaos zone emerges (above a threshold in the primaries' mass ratio) due to overlapping of the orbital resonances corresponding to the integer ratios p:1 between the tertiary and the central binary periods. In this zone, the unlimited chaotic orbital diffusion of the tertiary takes place, up to its ejection from the system. The primaries' mass ratio, above which such a chaotic zone is universally present at all initial eccentricities of the tertiary, is estimated. The diversity of the observed orbital configurations of biplanetary and circumbinary exosystems is shown to be in accord with the existence of the primaries' mass parameter threshold.

  18. ShoreZone Mapped Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set is a polyline file of mapped ShoreZone units which correspond with data records found in the Unit, Xshr, BioUnit, and BioBand tables of this...

  19. ISOLDE target zone control room

    CERN Multimedia

    2016-01-01

    Operating the ISOLDE target handling robots from the dedicated control room in building 197. Monitors showing the movements of the robots (GPS in this case) in the target zone. The footage shows the actual operation by the operator as well as the different equipment such as camera electronics, camera motor controls, camera monitors and Kuka robot controls touch panel.

  20. Will integrated surveillance systems for vectors and vector-borne diseases be the future of controlling vector-borne diseases? A practical example from China.

    Science.gov (United States)

    Wu, Y; Ling, F; Hou, J; Guo, S; Wang, J; Gong, Z

    2016-07-01

    Vector-borne diseases are one of the world's major public health threats and annually responsible for 30-50% of deaths reported to the national notifiable disease system in China. To control vector-borne diseases, a unified, effective and economic surveillance system is urgently needed; all of the current surveillance systems in China waste resources and/or information. Here, we review some current surveillance systems and present a concept for an integrated surveillance system combining existing vector and vector-borne disease monitoring systems. The integrated surveillance system has been tested in pilot programmes in China and led to a 21·6% cost saving in rodent-borne disease surveillance. We share some experiences gained from these programmes. PMID:26899818

  1. Sickness presenteeism in Spanish-born and immigrant workers in Spain

    Directory of Open Access Journals (Sweden)

    Felt Emily

    2010-12-01

    Full Text Available Abstract Background Previous studies have shown that immigrant workers face relatively worse working and employment conditions, as well as lower rates of sickness absence than native-born workers. This study aims to assess rates of sickness presenteeism in a sample of Spanish-born and foreign-born workers according to different characteristics. Methods A cross-sectional survey was conducted amongst a convenience sample of workers (Spanish-born and foreign-born, living in four Spanish cities: Barcelona, Huelva, Madrid and Valencia (2008-2009. Sickness presenteeism information was collected through two items in the questionnaire ("Have you had health problems in the last year?" and "Have you ever had to miss work for any health problem?" and was defined as worker who had a health problem (answered yes, first item and had not missed work (answered no, second item. For the analysis, the sample of 2,059 workers (1,617 foreign-born who answered yes to health problems was included. After descriptives, logistic regressions were used to establish the association between origin country and sickness presenteeism (adjusted odds ratios aOR; 95% confidence interval 95%CI. Analyses were stratified per time spent in Spain among foreign-born workers. Results All of the results refer to the comparison between foreign-born and Spanish-born workers as a whole, and in some categories relating to personal and occupational conditions. Foreign-born workers were more likely to report sickness presenteeism compared with their Spanish-born counterparts, especially those living in Spain for under 2 years [Prevalence: 42% in Spanish-born and 56.3% in Foreign-born; aOR 1.77 95%CI 1.24-2.53]. In case of foreign-born workers (with time in Spain Conclusions Immigrant workers report more sickness presenteeism than their Spanish-born counterparts. These results could be related to precarious work and employment conditions of immigrants. Immigrant workers should benefit from the

  2. Born Global Challenges and Performance - A Study on Competences, Routines, and Corporate Governance Structure of Born Global Software Companies in Sweden and Norway

    OpenAIRE

    Tunca, Burak; Yuditskaya, Evgenia

    2009-01-01

    Problem: How do the born global firms overcome challenges and sustain performance in international markets through their competences, routines, and corporate governance structure? Purpose: The purpose of this thesis is to explore the competences, routines, and corporate governance structure of born global companies, and understand their role in overcoming challenges of early internationalization and sustaining performance in international markets from early days. Method: This research is cond...

  3. Unsaturated Zone and Saturated Zone Transport Properties (U0100)

    International Nuclear Information System (INIS)

    This Analysis/Model Report (AMR) summarizes transport properties for the lower unsaturated zone hydrogeologic units and the saturated zone at Yucca Mountain and provides a summary of data from the Busted Butte Unsaturated Zone Transport Test (UZTT). The purpose of this report is to summarize the sorption and transport knowledge relevant to flow and transport in the units below Yucca Mountain and to provide backup documentation for the sorption parameters decided upon for each rock type. Because of the complexity of processes such as sorption, and because of the lack of direct data for many conditions that may be relevant for Yucca Mountain, data from systems outside of Yucca Mountain are also included. The data reported in this AMR will be used in Total System Performance Assessment (TSPA) calculations and as general scientific support for various Process Model Reports (PMRs) requiring knowledge of the transport properties of different materials. This report provides, but is not limited to, sorption coefficients and other relevant thermodynamic and transport properties for the radioisotopes of concern, especially neptunium (Np), plutonium (Pu), Uranium (U), technetium (Tc), iodine (I), and selenium (Se). The unsaturated-zone (UZ) transport properties in the vitric Calico Hills (CHv) are discussed, as are colloidal transport data based on the Busted Butte UZTT, the saturated tuff, and alluvium. These values were determined through expert elicitation, direct measurements, and data analysis. The transport parameters include information on interactions of the fractures and matrix. In addition, core matrix permeability data from the Busted Butte UZTT are summarized by both percent alteration and dispersion

  4. Unsaturated Zone and Saturated Zone Transport Properties (U0100)

    Energy Technology Data Exchange (ETDEWEB)

    J. Conca

    2000-12-20

    This Analysis/Model Report (AMR) summarizes transport properties for the lower unsaturated zone hydrogeologic units and the saturated zone at Yucca Mountain and provides a summary of data from the Busted Butte Unsaturated Zone Transport Test (UZTT). The purpose of this report is to summarize the sorption and transport knowledge relevant to flow and transport in the units below Yucca Mountain and to provide backup documentation for the sorption parameters decided upon for each rock type. Because of the complexity of processes such as sorption, and because of the lack of direct data for many conditions that may be relevant for Yucca Mountain, data from systems outside of Yucca Mountain are also included. The data reported in this AMR will be used in Total System Performance Assessment (TSPA) calculations and as general scientific support for various Process Model Reports (PMRs) requiring knowledge of the transport properties of different materials. This report provides, but is not limited to, sorption coefficients and other relevant thermodynamic and transport properties for the radioisotopes of concern, especially neptunium (Np), plutonium (Pu), Uranium (U), technetium (Tc), iodine (I), and selenium (Se). The unsaturated-zone (UZ) transport properties in the vitric Calico Hills (CHv) are discussed, as are colloidal transport data based on the Busted Butte UZTT, the saturated tuff, and alluvium. These values were determined through expert elicitation, direct measurements, and data analysis. The transport parameters include information on interactions of the fractures and matrix. In addition, core matrix permeability data from the Busted Butte UZTT are summarized by both percent alteration and dispersion.

  5. The Acculturation Experiences of Foreign-Born Students of Color in Physics

    Science.gov (United States)

    Fries-Britt, Sharon; George Mwangi, Chrystal A.; Peralta, Alicia M.

    2014-01-01

    This study focuses on 15 foreign-born students majoring in physics who are also racial/ethnic minorities. We address the research question: What are the acculturation experiences of foreign-born Students of Color majoring in physics? Berry's (2003) theory of acculturation and Bandura's (1994) theory of self-efficacy were substantive…

  6. Language functions in preterm-born children: A systematic review and meta-analysis

    NARCIS (Netherlands)

    I.L. Van Noort-van Der Spek (Inge); M-C. Franken (Marie-Christine); N. Weisglas-Kuperus (Nynke)

    2012-01-01

    textabstractBACKGROUND AND OBJECTIVE: Preterm-born children (born children. It is unknown whether these problems decrease, deteriorate, or remain stable over time. The goal of this research was to determine the dev

  7. Can a Web-Based Course Improve Communicative Competence of Foreign-Born Nurses?

    Science.gov (United States)

    Van Schaik, Eileen; Lynch, Emily M.; Stoner, Susan A.; Sikorski, Lorna D.

    2014-01-01

    In the years since World War II, the United States has grown increasingly dependent on foreign-born healthcare personnel at all levels of the healthcare system. Foreign-born nurses report that while they may feel clinically competent, they often feel unprepared for the use of English in the healthcare setting (Davis & Nichols, 2002; Guttman,…

  8. The Developmental Outcome of Children Born to Heroin-Dependent Mothers, Raised at Home or Adopted.

    Science.gov (United States)

    Ornoy, Asher; And Others

    1996-01-01

    Children born to heroin-dependent mothers (n=83) were compared to 76 children born to heroin-dependent fathers and to 3 control groups with and without environmental deprivation and health problems. Results found that developmental delays and behavioral disorders found among heroin-exposed children resulted primarily from severe environmental…

  9. Developmental Delay in Moderately Preterm-Born Children at School Entry

    NARCIS (Netherlands)

    Kerstjens, Jorien M.; de Winter, Andrea F.; Bocca-Tjeertes, Inger F.; ten Vergert, Elisabeth M. J.; Reijneveld, Sijmen A.; Bos, Arend F.; B0cca-Tjeertes, I.F.

    2011-01-01

    Objective To determine the prevalence and nature of developmental delay at preschool age in infants born moderately preterm compared with those born full-term and early preterm. Study design Parents of 927 moderate preterm infants (32-35(+) 6 weeks gestation), 512 early preterm infants ( Results Abn

  10. Long-Term Cognitive Outcomes of Infants Born Moderately and Late Preterm

    Science.gov (United States)

    Odd, David Edward; Emond, Alan; Whitelaw, Andrew

    2012-01-01

    Aim: To investigate whether infants born late preterm have poorer cognitive outcomes than term-born infants. Method: A cohort study based on the Avon Longitudinal Study of Parents and Children. Cognitive measures were assessed between the ages of 8 and 11 years. Exposure groups were defined as moderate/late preterm (32-36 weeks' gestation) or term…

  11. School-Aged Children Born Preterm: Review of Functioning across Multiple Domains and Guidelines for Assessment

    Science.gov (United States)

    Dempsey, Allison G.; Keller-Margulis, Milena; Mire, Sarah; Abrahamson, Catherine; Dutt, Sonia; Llorens, Ashlie; Payan, Anita

    2015-01-01

    Children born preterm are at risk for developmental deficits across multiple functional domains. As the rate of survival for preterm infants increases due to medical advancements, a greater understanding is needed for how to meet the needs of this growing population in schools. Because approximately 50-70% of children born preterm require…

  12. Falling Through the Cracks: Lack of Health Insurance Among Elderly Foreign- and Native-Born Blacks.

    Science.gov (United States)

    Stewart, Karyn A; London, Andrew S

    2015-10-01

    Little research examines lack of health insurance among elderly Black immigrants in the US. We use data from the 2008 American Community Survey to describe variation in insurance coverage and conduct multivariate logistic regression analyses of uninsurance. Among elderly Blacks, 1.7% of the US-born were uninsured, compared to 8.4% of the Latin American and Caribbean-born, 23.2% of the African-born, and 9.3% of those born in other regions. In multivariate models, relative to the US-born, the odds of being uninsured were significantly higher among each immigrant group. Among immigrants, the odds of being uninsured were 3.80 times higher among African-born than Latin American and Caribbean-born immigrants net of demographic and socioeconomic controls. This difference was explained by the inclusion of either year of immigration or length of residence. Relative to Latin America and Caribbean-born immigrants, the odds of being uninsured were significantly higher among immigrants from "other" regions only in the model that included the immigration-related variables. This suppression effect was evident when either length of residence or citizenship was controlled. Recently-arrived, elderly Black immigrants fall through the cracks of insurance coverage. Results are discussed in relation to public and private safety net options. PMID:25294416

  13. Doxapram and developmental delay at 12 months in children born extremely preterm

    DEFF Research Database (Denmark)

    Lando, Ane; Klamer, Anja; Jonsbo, Finn;

    2005-01-01

    AIM: To examine the relation of doxapram to a developmental score achieved by a structured telephone interview in a group of extremely-preterm-born children. METHODS: Parents of 88 children born extremely preterm were contacted by telephone and interviewed by a structured questionnaire (R-PDQ) wh...

  14. High-throuhgput screening of tick-borne pathogens in Europe

    NARCIS (Netherlands)

    Michelet, L.; Delannoy, S.; Devillers, E.; Umhang, G.; Aspan, A.; Juremalm, M.; Chirico, J.; Wal, van der F.J.; Sprong, H.; Boye Pihl, T.P.; Klitgaard, K.; Bodker, R.; Fach, P.; Moutailler, S.

    2014-01-01

    Due to increased travel, climatic, and environmental changes, the incidence of tick-borne disease in both humans and animals is increasing throughout Europe. Therefore, extended surveillance tools are desirable. To accurately screen tick-borne pathogens (TBPs), a large scale epidemiological study wa

  15. Vector-borne diseases: the basic reproduction number R0 and risk maps

    NARCIS (Netherlands)

    Hartemink, N.A.

    2009-01-01

    This thesis deals with the derivation of the basic reproduction number (R0) for vector-borne diseases, in the context of studying the effect of climate change on the risk of emergence diseases. Vector-borne diseases are transmitted from an infected individual to another individual by vectors, usuall

  16. Testing Born's rule in quantum mechanics for three mutually exclusive events

    DEFF Research Database (Denmark)

    Sollner, Immo Nathanael; Gschösser, Benjamin; Mai, Patrick;

    2012-01-01

    We present a new experimental approach using a three-path interferometer and find a tighter empirical upper bound on possible violations of Born's Rule. A deviation from Born's rule would result in multi-order interference. Among the potential systematic errors that could lead to an apparent viol...

  17. Higher rates of behavioural and emotional problems at preschool age in children born moderately preterm

    NARCIS (Netherlands)

    Potijk, Marieke R.; de Winter, Andrea F.; Bos, Arend F.; Kerstjens, Jorien M.; Reijneveld, Sijmen A.

    2012-01-01

    Objective To compare preschool children born moderately preterm (MP; 32-35 weeks' gestation) and children born at term (38-41 weeks' gestation) regarding the occurrence of behavioural and emotional problems, overall, for separate types of problems and by gender. Design Prospective cohort study consi

  18. Acculturative Stress and Gang Involvement among Latinos: U.S.-Born versus Immigrant Youth

    Science.gov (United States)

    Barrett, Alice N.; Kuperminc, Gabriel P.; Lewis, Kelly M.

    2013-01-01

    Gang involvement is an increasing issue among Latino youth, yet nuanced research on its potential causes is scarce. Quantitative and qualitative data were used to explore links between acculturative stress and gang involvement among immigrant and U.S.-born Latino middle school students (N = 199). Regression analyses showed that U.S.-born youths…

  19. County Differences in Mortality among Foreign-Born Compared to Native Swedes 1970–1999

    Directory of Open Access Journals (Sweden)

    Björn Albin

    2012-01-01

    Full Text Available Background. Regional variations in mortality and morbidity have been shown in Europe and USA. Longitudinal studies have found increased mortality, dissimilarities in mortality pattern, and differences in utilization of healthcare between foreign- and native-born Swedes. No study has been found comparing mortality among foreign-born and native-born Swedes in relation to catchment areas/counties. Methods. The aim was to describe and compare mortality among foreign-born persons and native Swedes during 1970–1999 in 24 counties in Sweden. Data from the Statistics Sweden and the National Board of Health and Welfare was used, and the database consisted of 723,948 persons, 361,974 foreign-born living in Sweden in 1970 and aged 16 years and above and 361,974 matched Swedish controls. Results. Latest county of residence independently explained higher mortality among foreign-born persons in all but four counties; OR varied from 1.01 to 1.29. Counties with a more rural structure showed the highest differences between foreign-born persons and native controls. Foreign-born persons had a lower mean age (1.0–4.3 years at time of death. Conclusion. County of residence influences mortality; higher mortality is indicated among migrants than native Swedes in counties with a more rural structure. Further studies are needed to explore possible explanations.

  20. Stress and Coping among Migrant and Local-Born Adolescents in Hong Kong

    Science.gov (United States)

    Tam, Vicky Chiu-Wan; Lam, Rebecca Siu-Yuk

    2005-01-01

    This study compared stress and coping among 243 migrant and 750 local-born Chinese adolescents in Hong Kong. Findings showed that compared to their local-born counterparts, migrants showed no difference in perceived stress, whereas they were less likely to use withdrawal coping and showed higher self-esteem and less delinquent behavior. Adjustment…