Modeling CCN effects on tropical convection: An statistical perspective

Science.gov (United States)

Carrio, G. G.; Cotton, W. R.; Massie, S. T.

2012-12-01

This modeling study examines the response of tropical convection to the enhancement of CCN concentrations from a statistical perspective. The sensitivity runs were performed using RAMS version 6.0, covering almost the entire Amazonian Aerosol Characterization Experiment period (AMAZE, wet season of 2008). The main focus of the analysis was the indirect aerosol effects on the probability density functions (PDFs) of various cloud properties. RAMS was configured to work with four two-way interactive nested grids with 42 vertical levels and horizontal grid spacing of 150, 37.5, 7.5, and 1.5 km. Grids 2 and 3 were used to simulate the synoptic and mesoscale environments, while grid 4 was used to resolve deep convection. Comparisons were made using the finest grid with a domain size of 300 X 300km, approximately centered on the city of Manaus (3.1S, 60.01W). The vertical grid was stretched using with 75m spacing at the finest levels to provide better resolution within the first 1.5 km, and the model top extended to approximately 22 km above ground level. RAMS was initialized on February 10 2008 (00:00 UTC), the length of simulations was 32 days, and GSF data were used for initialization and nudging of the coarser-grid boundaries. The control run considered a CCN concentration of 300cm-3 while other several other simulations considered an influx of higher CCN concentrations (up to 1300/cc) . The latter concentration was observed near the end of the AMAZE project period. Both direct and indirect effects of these CCN particles were considered. Model output data (finest grid) every 15 min were used to compute the PDFs for each model level. When increasing aerosol concentrations, significant impacts were simulated for the PDFs of the water contents of various hydrometeors, vertical motions, area with precipitation, latent heat releases, among other quantities. In most cases, they exhibited a peculiar non-monotonic response similar to that seen in two previous studies of ours

Hypoxia-inducible factor (HIF)-1α and CCN2 form a regulatory circuit in hypoxic nucleus pulposus cells: CCN2 suppresses HIF-1α level and transcriptional activity.

Science.gov (United States)

Tran, Cassie M; Fujita, Nobuyuki; Huang, Bau-Lin; Ong, Jessica R; Lyons, Karen M; Shapiro, Irving M; Risbud, Makarand V

2013-05-03

The objective of the study was to investigate if hypoxia-inducible factor (HIF)-1α and connective tissue growth factor (CCN2) form a regulatory network in hypoxic nucleus pulposus (NP) cells. A decrease in CCN2 expression and proximal promoter activity was observed in NP cells after hypoxic culture. Analysis of both human and mouse CCN2 promoters using the JASPAR core database revealed the presence of putative hypoxia response elements. Transfection experiments showed that both promoter activities and CCN2 expression decreases in hypoxia in a HIF-1α-dependent fashion. Interestingly, deletion analysis and mutation of the hypoxia responsive elements individually or in combination resulted in no change in promoter activity in response to hypoxia or in response to HIF-1α, suggesting an indirect mode of regulation. Notably, silencing of endogenous CCN2 increased HIF-1α levels and its target gene expression, suggesting a role for CCN2 in controlling basal HIF-1α levels. On the other hand, treatment of cells with rCCN2 resulted in a decrease in the ability of HIF-1α transactivating domain to recruit co-activators and diminished target gene expression. Last, knockdown of CCN2 in NP cells results in a significant decrease in GAG synthesis and expression of AGGRECAN and COLLAGEN II. Immunohistochemical staining of intervertebral discs of Ccn2 null embryos shows a decrease in aggrecan. These findings reveal a negative feedback loop between CCN2 and HIF-1α in NP cells and demonstrate a role for CCN2 in maintaining matrix homeostasis in this tissue.

Quantifying the Relationship between Organic Aerosol Composition and Hygroscopicity/CCN Activity

Energy Technology Data Exchange (ETDEWEB)

Ziemann, Paul J. [Univ. of California, Riverside, CA (United States); Kreidenweis, Sonia M. [Colorado State Univ., Fort Collins, CO (United States); Petters, Markus D. [North Carolina State Univ., Raleigh, NC (United States)

2013-06-30

The overall objective for this project was to provide the data and underlying process level understanding necessary to facilitate the dynamic treatment of organic aerosol CCN activity in future climate models. The specific objectives were as follows: (1) employ novel approaches to link organic aerosol composition and CCN activity, (2) evaluate the effects of temperature and relative humidity on organic aerosol CCN activity, and (3) develop parameterizations to link organic aerosol composition and CCN activity.

An Analysis of Pathological Activities of CCN Proteins in Joint Disorders: Mechanical Stretch-Mediated CCN2 Expression in Cultured Meniscus Cells.

Science.gov (United States)

Furumatsu, Takayuki; Ozaki, Toshifumi

2017-01-01

The multifunctional growth factor CYR61/CTGF/NOV (CCN) 2, also known as connective tissue growth factor, regulates cellular proliferation, differentiation, and tissue regeneration. Recent literatures have described important roles of CCN2 in the meniscus metabolism. However, the mechanical stress-mediated transcriptional regulation of CCN2 in the meniscus remains unclear. The meniscus is a fibrocartilaginous tissue that controls complex biomechanics of the knee joint. Therefore, the injured unstable meniscus has a poor healing potential especially in the avascular inner region. In addition, dysfunction of the meniscus correlates with the progression of degenerative knee joint disorders and joint space narrowing. Here, we describe an experimental approach that investigates the distinct cellular behavior of inner and outer meniscus cells in response to mechanical stretch. Our experimental model can analyze the relationships between stretch-induced CCN2 expression and its functional role in the meniscus homeostasis.

CCN4/WISP-1 positively regulates chondrogenesis by controlling TGF-β3 function.

Science.gov (United States)

Yoshioka, Yuya; Ono, Mitsuaki; Maeda, Azusa; Kilts, Tina M; Hara, Emilio Satoshi; Khattab, Hany; Ueda, Junji; Aoyama, Eriko; Oohashi, Toshitaka; Takigawa, Masaharu; Young, Marian F; Kuboki, Takuo

2016-02-01

The CCN family of proteins plays important roles in development and homeostasis of bone and cartilage. To understand the role of CCN4 in chondrogenesis, human bone marrow stromal cells (hBMSCs) were transduced with CCN4 adenovirus (adCCN4) or siRNA to CCN4 (siCCN4) in the presence or absence of transforming growth factor-β3 (TGF-β3). Overexpression of CCN4 enhanced TGF-β3-induced SMAD2/3 phosphorylation and chondrogenesis of hBMSCs in an in vitro assay using a micromass culture model. On the other hand, knockdown of CCN4 inhibited the TGF-β3-induced SMAD2/3 phosphorylation and synthesis of cartilage matrix in micromass cultures of hBMSCs. Immunoprecipitation-western blot analysis revealed that CCN4 bound to TGF-β3 and regulated the ability of TGF-β3 to bind to hBMSCs. In vivo analysis confirmed there was a significant decrease in the gene expression levels of chondrocyte markers in cartilage samples from Ccn4-knock out (KO) mice, compared to those from wild type (WT) control. In order to investigate the regenerative properties of the articular cartilage in Ccn4-KO mice, articular cartilage defects were surgically performed in the knee joints of young mice, and the results showed that the cartilage was partially repaired in WT mice, but not in Ccn4-KO mice. In conclusion, these results show, for the first time, that CCN4 has a positive influence on chondrogenic differentiation by modulating the effects of TGF-β3. Copyright © 2015 Elsevier Inc. All rights reserved.

Satellite retrieval of cloud condensation nuclei concentrations by using clouds as CCN chambers

Science.gov (United States)

Rosenfeld, Daniel; Zheng, Youtong; Hashimshoni, Eyal; Pöhlker, Mira L.; Jefferson, Anne; Pöhlker, Christopher; Yu, Xing; Zhu, Yannian; Liu, Guihua; Yue, Zhiguo; Fischman, Baruch; Li, Zhanqing; Giguzin, David; Goren, Tom; Artaxo, Paulo; Pöschl, Ulrich

2016-01-01

Quantifying the aerosol/cloud-mediated radiative effect at a global scale requires simultaneous satellite retrievals of cloud condensation nuclei (CCN) concentrations and cloud base updraft velocities (Wb). Hitherto, the inability to do so has been a major cause of high uncertainty regarding anthropogenic aerosol/cloud-mediated radiative forcing. This can be addressed by the emerging capability of estimating CCN and Wb of boundary layer convective clouds from an operational polar orbiting weather satellite. Our methodology uses such clouds as an effective analog for CCN chambers. The cloud base supersaturation (S) is determined by Wb and the satellite-retrieved cloud base drop concentrations (Ndb), which is the same as CCN(S). Validation against ground-based CCN instruments at Oklahoma, at Manaus, and onboard a ship in the northeast Pacific showed a retrieval accuracy of ±25% to ±30% for individual satellite overpasses. The methodology is presently limited to boundary layer not raining convective clouds of at least 1 km depth that are not obscured by upper layer clouds, including semitransparent cirrus. The limitation for small solar backscattering angles of <25° restricts the satellite coverage to ∼25% of the world area in a single day. PMID:26944081

Mechanical stretch increases CCN2/CTGF expression in anterior cruciate ligament-derived cells

Energy Technology Data Exchange (ETDEWEB)

Miyake, Yoshiaki [Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama (Japan); Department of Biochemistry and Molecular Dentistry, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama (Japan); Furumatsu, Takayuki, E-mail: matino@md.okayama-u.ac.jp [Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama (Japan); Kubota, Satoshi; Kawata, Kazumi [Department of Biochemistry and Molecular Dentistry, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama (Japan); Ozaki, Toshifumi [Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama (Japan); Takigawa, Masaharu [Department of Biochemistry and Molecular Dentistry, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama (Japan)

2011-06-03

Highlights: {yields} CCN2/CTGF localizes to the ligament-to-bone interface, but is not to the midsubstance region of human anterior cruciate ligament (ACL). {yields} Mechanical stretch induces higher increase of CCN2/CTGF gene expression and protein secretion in ACL interface cells compared with ACL midsubstance cells. {yields} CCN2/CTGF treatment stimulates the proliferation of ACL interface cells. -- Abstract: Anterior cruciate ligament (ACL)-to-bone interface serves to minimize the stress concentrations that would arise between two different tissues. Mechanical stretch plays an important role in maintaining cell-specific features by inducing CCN family 2/connective tissue growth factor (CCN2/CTGF). We previously reported that cyclic tensile strain (CTS) stimulates {alpha}1(I) collagen (COL1A1) expression in human ACL-derived cells. However, the biological function and stress-related response of CCN2/CTGF were still unclear in ACL fibroblasts. In the present study, CCN2/CTGF was observed in ACL-to-bone interface, but was not in the midsubstance region by immunohistochemical analyses. CTS treatments induced higher increase of CCN2/CTGF expression and secretion in interface cells compared with midsubstance cells. COL1A1 expression was not influenced by CCN2/CTGF treatment in interface cells despite CCN2/CTGF stimulated COL1A1 expression in midsubstance cells. However, CCN2/CTGF stimulated the proliferation of interface cells. Our results suggest that distinct biological function of stretch-induced CCN2/CTGF might regulate region-specific phenotypes of ACL-derived cells.

Mechanical stretch increases CCN2/CTGF expression in anterior cruciate ligament-derived cells

International Nuclear Information System (INIS)

Miyake, Yoshiaki; Furumatsu, Takayuki; Kubota, Satoshi; Kawata, Kazumi; Ozaki, Toshifumi; Takigawa, Masaharu

2011-01-01

Highlights: → CCN2/CTGF localizes to the ligament-to-bone interface, but is not to the midsubstance region of human anterior cruciate ligament (ACL). → Mechanical stretch induces higher increase of CCN2/CTGF gene expression and protein secretion in ACL interface cells compared with ACL midsubstance cells. → CCN2/CTGF treatment stimulates the proliferation of ACL interface cells. -- Abstract: Anterior cruciate ligament (ACL)-to-bone interface serves to minimize the stress concentrations that would arise between two different tissues. Mechanical stretch plays an important role in maintaining cell-specific features by inducing CCN family 2/connective tissue growth factor (CCN2/CTGF). We previously reported that cyclic tensile strain (CTS) stimulates α1(I) collagen (COL1A1) expression in human ACL-derived cells. However, the biological function and stress-related response of CCN2/CTGF were still unclear in ACL fibroblasts. In the present study, CCN2/CTGF was observed in ACL-to-bone interface, but was not in the midsubstance region by immunohistochemical analyses. CTS treatments induced higher increase of CCN2/CTGF expression and secretion in interface cells compared with midsubstance cells. COL1A1 expression was not influenced by CCN2/CTGF treatment in interface cells despite CCN2/CTGF stimulated COL1A1 expression in midsubstance cells. However, CCN2/CTGF stimulated the proliferation of interface cells. Our results suggest that distinct biological function of stretch-induced CCN2/CTGF might regulate region-specific phenotypes of ACL-derived cells.

CTGF/CCN2 Postconditioning Increases Tolerance of Murine Hearts towards Ischemia-Reperfusion Injury.

Science.gov (United States)

Kaasbøll, Ole Jørgen; Moe, Ingvild Tronstad; Ahmed, Mohammad Shakil; Stang, Espen; Hagelin, Else Marie Valbjørn; Attramadal, Håvard

2016-01-01

Previous studies of ischemia-reperfusion injury (IRI) in hearts from mice with cardiac-restricted overexpression of CCN2 have shown that CCN2 increases tolerance towards IRI. The objectives of this study were to investigate to what extent post-ischemic administration of recombinant human CCN2 (rhCCN2) would limit infarct size and improve functional recovery and what signaling pathways are involved. Isolated mice hearts were perfused ad modum Langendorff, subjected to no-flow, global ischemia, and subsequently, exposed to mammalian cell derived, full-length (38-40kDa) rhCCN2 (250 nM) or vehicle during the first 15 min of a 60 min reperfusion period. Post-ischemic administration of rhCCN2 resulted in attenuation of infarct size from 58 ± 4% to 34 ± 2% (p concentration-dependent increase of cardiac phospho-GSK3β (serine-9) contents. We demonstrate that post-ischemic administration of rhCCN2 increases the tolerance of ex vivo-perfused murine hearts to IRI. Mechanistically, this postconditioning effect of rhCCN2 appeared to be mediated by activation of the reperfusion injury salvage kinase pathway as demonstrated by sensitivity to PI3 kinase inhibition and increased CCN2-induced phosphorylation of GSK3β (Ser-9). Thus, the rationale for testing rhCCN2-mediated post-ischemic conditioning of the heart in more complex models is established.

CTGF/CCN2 Postconditioning Increases Tolerance of Murine Hearts towards Ischemia-Reperfusion Injury.

Directory of Open Access Journals (Sweden)

Ole Jørgen Kaasbøll

Full Text Available Previous studies of ischemia-reperfusion injury (IRI in hearts from mice with cardiac-restricted overexpression of CCN2 have shown that CCN2 increases tolerance towards IRI. The objectives of this study were to investigate to what extent post-ischemic administration of recombinant human CCN2 (rhCCN2 would limit infarct size and improve functional recovery and what signaling pathways are involved.Isolated mice hearts were perfused ad modum Langendorff, subjected to no-flow, global ischemia, and subsequently, exposed to mammalian cell derived, full-length (38-40kDa rhCCN2 (250 nM or vehicle during the first 15 min of a 60 min reperfusion period.Post-ischemic administration of rhCCN2 resulted in attenuation of infarct size from 58 ± 4% to 34 ± 2% (p < 0.001 which was abrogated by concomitant administration of the PI3 kinase inhibitor LY294002 (45 ± 3% vs. 50 ± 3%, ns. In congruence with reduction of infarct size rhCCN2 also improved recovery of left ventricular developed pressure (p < 0.05. Western blot analyses of extracts of ex vivo-perfused murine hearts also revealed that rhCCN2 evoked concentration-dependent increase of cardiac phospho-GSK3β (serine-9 contents.We demonstrate that post-ischemic administration of rhCCN2 increases the tolerance of ex vivo-perfused murine hearts to IRI. Mechanistically, this postconditioning effect of rhCCN2 appeared to be mediated by activation of the reperfusion injury salvage kinase pathway as demonstrated by sensitivity to PI3 kinase inhibition and increased CCN2-induced phosphorylation of GSK3β (Ser-9. Thus, the rationale for testing rhCCN2-mediated post-ischemic conditioning of the heart in more complex models is established.

Cyr61/CCN1 displays high-affinity binding to the somatomedin B(1-44 domain of vitronectin.

Directory of Open Access Journals (Sweden)

Ivo M B Francischetti

2010-02-01

Full Text Available Cyr61 is a member of the CCN (Cyr61, connective tissue growth, NOV family of extracellular-associated (matricellular proteins that present four distinct functional modules, namely insulin-like growth factor binding protein (IGFBP, von Willebrand factor type C (vWF, thrombospondin type 1 (TSP, and C-terminal growth factor cysteine knot (CT domain. While heparin sulphate proteoglycans reportedly mediate the interaction of Cyr61 with the matrix and cell surface, the role of other extracellular associated proteins has not been revealed.In this report, surface plasmon resonance (SPR experiments and solid-phase binding assays demonstrate that recombinant Cyr61 interacts with immobilized monomeric or multimeric vitronectin (VTNC with K(D in the nanomolar range. Notably, the binding site for Cyr61 was identified as the somatomedin B domain (SMTB(1-44 of VTNC, which mediates its interaction with PAI-1, uPAR, and integrin alphav beta3. Accordingly, PAI-1 outcompetes Cyr61 for binding to immobilized SMTB(1-44, and Cyr61 attenuates uPAR-mediated U937 adhesion to VTNC. In contrast, isothermal titration calorimetry shows that Cyr61 does not display high-affinity binding for SMTB(1-44 in solution. Nevertheless, competitive ELISA revealed that multimeric VTNC, heat-modified monomeric VTNC, or SMTB(1-44 at high concentrations attenuate Cyr61 binding to immobilized VTNC, while monomeric VTNC was ineffective. Therefore, immobilization of VTNC exposes cryptic epitopes that recognize Cyr61 with high affinity, as reported for a number of antibodies, beta-endorphin, and other molecules.The finding that Cyr61 interacts with the SMTB(1-44 domain suggests that VTNC represent a point of anchorage for CCN family members to the matrix. Results are discussed in the context of the role of CCN and VTNC in matrix biology and angiogenesis.

Hygroscopicity and composition of Alaskan Arctic CCN during April 2008

Directory of Open Access Journals (Sweden)

R. H. Moore

2011-11-01

Full Text Available We present a comprehensive characterization of cloud condensation nuclei (CCN sampled in the Alaskan Arctic during the 2008 Aerosol, Radiation, and Cloud Processes affecting Arctic Climate (ARCPAC project, a component of the POLARCAT and International Polar Year (IPY initiatives. Four distinct air mass types were sampled including a cleaner Arctic background and a relatively pristine sea ice boundary layer as well as biomass burning and anthropogenic pollution plumes. Despite differences in chemical composition, inferred aerosol hygroscopicities were fairly invariant and ranged from κ = 0.1–0.3 over the atmospherically-relevant range of water vapor supersaturations studied. Organic aerosols sampled were found to be well-oxygenated, consistent with long-range transport and aerosol aging processes. However, inferred hygroscopicities are less than would be predicted based on previous parameterizations of biogenic oxygenated organic aerosol, suggesting an upper limit on organic aerosol hygroscopicity above which κ is less sensitive to the O:C ratio. Most Arctic aerosols act as CCN above 0.1 % supersaturation, although the data suggest the presence of an externally-mixed, non-CCN-active mode comprising approximately 0–20% of the aerosol number. CCN closure was assessed using measured size distributions, bulk chemical composition, and assumed aerosol mixing states; CCN predictions tended toward overprediction, with the best agreement (±0–20 % obtained by assuming the aerosol to be externally-mixed with soluble organics. Closure also varied with CCN concentration, and the best agreement was found for CCN concentrations above 100 cm⁻³ with a 1.5- to 3-fold overprediction at lower concentrations.

Mechanism of cancer-induced bone destruction: An association of connective tissue growth factor (CTGF/CCN2 in the bone metastasis

Directory of Open Access Journals (Sweden)

Tsuyoshi Shimo

2011-02-01

Full Text Available Connective tissue growth factor (CTGF/CCN2 is a member of the CCN family, a novel class of extracellular signal modulators. CCN2 is composed of four conserved modules connected in tandem, each of which is rich in cysteines and highly interactive with other molecules. CCN2 has various biological functions, being active in developmental processes including angiogenesis, chondrogenesis, and osteogenesis. Recently CCN2 has gained more clinical interest due to its role in cancer-induced bone destruction. In this article, the role of CCN2 in bone-destroying events as an organizer of the microenvironmental cell society is comprehensively described, and a brief summary of the recent findings on regulatory factors involved in tumor-induced bone disease is given.

CCN and IN Effects on Cloud Properties and Precipitation - Case Studies from CalWater 2011

Science.gov (United States)

Fan, J.; Leung, L.; Comstock, J. M.; Tomlinson, J. M.

2011-12-01

Aerosols in the atmosphere can serve as cloud condensation nuclei (CCN) and ice nuclei (IN) to modify cloud microphysical processes, which could potentially change the location, intensity, and type of precipitation. Dust aerosols are often observed over California in the Sierra Nevada Mountains in winter/spring, associated with long-range transport from Asia. Although anthropogenic pollution has been postulated to contribute to reduction of precipitation in the Sierra Nevada Mountains, the effects of dust aerosols on the winter clouds and precipitation has not been examined in detail particularly with model simulations. We incorporate recent progress in ice nucleation parameterizations to link dust with ice crystal formation in a spectral-bin cloud microphysical model coupled with WRF, to exclusively look into how dust can possibly affect cloud properties and precipitation type and intensity. Simulations are carried out for two cases under different environmental conditions with atmospheric river (AR) and Sierra barrier jet (SBJ) from the CalWater 2011 field campaign. It is shown that increasing IN concentrations or adding a dust layer at 4-6 km as IN enhances surface rain and snow due to enhanced production of ice and snow in clouds. However, increasing CCN suppresses surface rain and snow, and significantly redistributes surface precipitation upwind and downwind of the mountains, with important implication to improving our understanding of the impacts of aerosols on orographic precipitation and water supply in the region.

Increased Expression of CCN2 in the Red Flashing Light-Induced Myopia in Guinea Pigs

Directory of Open Access Journals (Sweden)

Hong Wang

2013-01-01

Full Text Available Visual environment plays an important role in the occurrence of myopia. We previously showed that the different flashing lights could result in distinct effects on the ocular growth and development of myopia. CCN2 has been reported to regulate various cellular functions and biological processes. However, whether CCN2 signaling was involved in the red flashing light-induced myopia still remains unknown. In the present study, we investigated the effects of the red flashing lights exposure on the refraction and axial length of the eyes in vivo and then evaluated their effects on the expression of CCN2 and TGF-β in sclera tissues. Our data showed that the eyes exposed to the red flashing light became more myopic with a significant increase of the axial length and decrease of the refraction. Both CCN2 and TGF-β, as well as p38 MAPK and PI3K, were highly expressed in the sclera tissues exposed to the red flashing light. Both CCN2 and TGF-β were found to have the same gene expression profile in vivo. In conclusion, our findings found that CCN2 signaling pathway plays an important role in the red flashing light-induced myopia in vivo. Moreover, our study establishes a useful animal model for experimental myopia research.

CCN activation of fumed silica aerosols mixed with soluble pollutants

Science.gov (United States)

Dalirian, M.; Keskinen, H.; Ahlm, L.; Ylisirniö, A.; Romakkaniemi, S.; Laaksonen, A.; Virtanen, A.; Riipinen, I.

2014-09-01

Particle-water interactions of completely soluble or insoluble particles are fairly well understood but less is known of aerosols consisting of mixtures of soluble and insoluble components. In this study, laboratory measurements were performed to investigate cloud condensation nuclei (CCN) activity of silica particles coated with ammonium sulphate (a salt), sucrose (a sugar) and bovine serum albumin known as BSA (a protein). In addition, the agglomerated structure of the silica particles was investigated by estimating the surface equivalent diameter based on measurements with a Differential Mobility Analyzer (DMA) and an Aerosol Particle Mass Analyzer (APM). By using the surface equivalent diameter the non-sphericity of the particles containing silica was accounted for when estimating CCN activation. Furthermore, characterizing critical supersaturations of particles consisting of pure soluble on insoluble compounds using existing frameworks showed that the CCN activation of single component particles was in good agreement with Köhler and adsorption theory based models when the agglomerated structure was accounted for. For mixed particles the CCN activation was governed by the soluble components, and the soluble fraction varied considerably with particle size for our wet-generated aerosols. Our results confirm the hypothesis that knowing the soluble fraction is the key parameter needed for describing the CCN activation of mixed aerosols, and highlight the importance of controlled coating techniques for acquiring a detailed understanding of the CCN activation of atmospheric insoluble particles mixed with soluble pollutants.

CCN activation experiments with adipic acid: effect of particle phase and adipic acid coatings on soluble and insoluble particles

Directory of Open Access Journals (Sweden)

S. S. Hings

2008-07-01

Full Text Available Slightly soluble atmospherically relevant organic compounds may influence particle CCN activity and therefore cloud formation. Adipic acid is a frequently employed surrogate for such slightly soluble organic materials. The 11 published experimental studies on the CCN activity of adipic acid particles are not consistent with each other nor do they, in most cases, agree with the Köhler theory. The CCN activity of adipic acid aerosol particles was studied over a significantly wider range of conditions than in any previous single study. The work spans the conditions of the previous studies and also provides alternate methods for producing "wet" (deliquesced solution droplets and dry adipic acid particles without the need to produce them by atomization of aqueous solutions. The experiments suggest that the scatter in the previously published CCN measurements is most likely due to the difficulty of producing uncontaminated adipic acid particles by atomization of solutions and possibly also due to uncertainties in the calibration of the instruments. The CCN activation of the small (d_m<150 nm initially dry particles is subject to a deliquescence barrier, while for the larger particles the activation follows the Köhler curve. Wet adipic acid particles follow the Köhler curve over the full range of particle diameters studied. In addition, the effect of adipic acid coatings on the CCN activity of both soluble and insoluble particles has also been studied. When a water-soluble core is coated by adipic acid, the CCN-hindering effect of particle phase is eliminated. An adipic acid coating on hydrophobic soot yields a CCN active particle. If the soot particle is relatively small (d_core≤102 nm, the CCN activity of the coated particles approaches the deliquescence line of adipic acid, suggesting that the total size of the particle determines CCN activation and the soot core acts as a scaffold.

Differential expression of CCN-family members in primary human bone marrow-derived mesenchymal stem cells during osteogenic, chondrogenic and adipogenic differentiation

Directory of Open Access Journals (Sweden)

Hendrich Christian

2005-03-01

Full Text Available Abstract Background The human cysteine rich protein 61 (CYR61, CCN1 as well as the other members of the CCN family of genes play important roles in cellular processes such as proliferation, adhesion, migration and survival. These cellular events are of special importance within the complex cellular interactions ongoing in bone remodeling. Previously, we analyzed the role of CYR61/CCN1 as an extracellular signaling molecule in human osteoblasts. Since mesenchymal stem cells of bone marrow are important progenitors for various differentiation pathways in bone and possess increasing potential for regenerative medicine, here we aimed to analyze the expression of CCN family members in bone marrow-derived human mesenchymal stem cells and along the osteogenic, the adipogenic and the chondrogenic differentiation. Results Primary cultures of human mesenchymal stem cells were obtained from the femoral head of patients undergoing total hip arthroplasty. Differentiation into adipocytes and osteoblasts was done in monolayer culture, differentiation into chondrocytes was induced in high density cell pellet cultures. For either pathway, established differentiation markers and CCN-members were analyzed at the mRNA level by RT-PCR and the CYR61/CCN1 protein was analyzed by immunocytochemistry. RT-PCR and histochemical analysis revealed the appropriate phenotype of differentiated cells (Alizarin-red S, Oil Red O, Alcian blue, alkaline phosphatase; osteocalcin, collagen types I, II, IX, X, cbfa1, PPARγ, aggrecan. Mesenchymal stem cells expressed CYR61/CCN1, CTGF/CCN2, CTGF-L/WISP2/CCN5 and WISP3/CCN6. The CYR61/CCN1 expression decreased markedly during osteogenic differentiation, adipogenic differentiation and chondrogenic differentiation. These results were confirmed by immuncytochemical analyses. WISP2/CCN5 RNA expression declined during adipogenic differentiation and WISP3/CCN6 RNA expression was markedly reduced in chondrogenic differentiation. Conclusion The

Boundary layer nucleation as a source of new CCN in savannah environment

Directory of Open Access Journals (Sweden)

L. Laakso

2013-02-01

Full Text Available The South African savannah region is a complex environment of air pollution and natural emissions influenced by a strong seasonal cycle in biomass burning and strong precipitation. However, the scarcity of long-term observations means that the knowledge of controlling aerosol processes in this environment is limited. Here we use a recent dataset of 18 months of aerosol size distribution observations trying to understand the annual cycle of cloud condensation nuclei (CCN.

Our observations show that the concentration of CCN-sized particles remains, in line with previous studies, high throughout the year with the highest concentrations during the dry winter and the lowest during the wet summer. During the wet season with reduced anthropogenic and biomass burning primary emissions, this pool of CCN is partly filled by boundary layer nucleation with subsequent growth. The enhanced importance of formation and growth during the wet season is addressed to increased biogenic activity together with enhanced free tropospheric removal decreasing the concentration of pre-existing CCN. During the dry season, while frequent new particle formation takes place, particle growth is reduced due to reduced condensing vapour concentrations. Thus in the dry season particles are not able to grow to sizes where they may act as CCN nearly as efficiently as during the wet season.

The observations are compared to simulations by a global aerosol model GLOMAP. To our surprise, the global aerosol model utilized to explain the observations was not capable of re-producing the characteristics of particle formation and the annual CCN cycle, despite earlier good performance in predicting the particle concentrations in a number of diverse environments, including the South African savannah region. While the average yearly CCN concentrations of modelled CCN is close to observed concentrations, the characteristics of nucleation bursts and subsequent growth are not

Connective tissue growth factor (CTGF/CCN2) is increased in peritoneal dialysis patients with high peritoneal solute transport rate

NARCIS (Netherlands)

Mizutani, Makoto; Ito, Yasuhiko; Mizuno, Masashi; Nishimura, Hayato; Suzuki, Yasuhiro; Hattori, Ryohei; Matsukawa, Yoshihisa; Imai, Masaki; Oliver, Noelynn; Goldschmeding, Roel; Aten, Jan; Krediet, Raymond T.; Yuzawa, Yukio; Matsuo, Seiichi

2010-01-01

Mizutani M, Ito Y, Mizuno M, Nishimura H, Suzuki Y, Hattori R, Matsukawa Y, Imai M, Oliver N, Goldschmeding R, Aten J, Krediet RT, Yuzawa Y, Matsuo S. Connective tissue growth factor (CTGF/CCN2) is increased in peritoneal dialysis patients with high peritoneal solute transport rate. Am J Physiol

CCN2/CTGF is required for matrix organization and to protect growth plate chondrocytes from cellular stress.

Science.gov (United States)

Hall-Glenn, Faith; Aivazi, Armen; Akopyan, Lusi; Ong, Jessica R; Baxter, Ruth R; Benya, Paul D; Goldschmeding, Roel; van Nieuwenhoven, Frans A; Hunziker, Ernst B; Lyons, Karen M

2013-08-01

CCN2 (connective tissue growth factor (CTGF/CCN2)) is a matricellular protein that utilizes integrins to regulate cell proliferation, migration and survival. The loss of CCN2 leads to perinatal lethality resulting from a severe chondrodysplasia. Upon closer inspection of Ccn2 mutant mice, we observed defects in extracellular matrix (ECM) organization and hypothesized that the severe chondrodysplasia caused by loss of CCN2 might be associated with defective chondrocyte survival. Ccn2 mutant growth plate chondrocytes exhibited enlarged endoplasmic reticula (ER), suggesting cellular stress. Immunofluorescence analysis confirmed elevated stress in Ccn2 mutants, with reduced stress observed in Ccn2 overexpressing transgenic mice. In vitro studies revealed that Ccn2 is a stress responsive gene in chondrocytes. The elevated stress observed in Ccn2-/- chondrocytes is direct and mediated in part through integrin α5. The expression of the survival marker NFκB and components of the autophagy pathway were decreased in Ccn2 mutant growth plates, suggesting that CCN2 may be involved in mediating chondrocyte survival. These data demonstrate that absence of a matricellular protein can result in increased cellular stress and highlight a novel protective role for CCN2 in chondrocyte survival. The severe chondrodysplasia caused by the loss of CCN2 may be due to increased chondrocyte stress and defective activation of autophagy pathways, leading to decreased cellular survival. These effects may be mediated through nuclear factor κB (NFκB) as part of a CCN2/integrin/NFκB signaling cascade.

Role of organic aerosols in CCN activation and closure over a rural background site in Western Ghats, India

Science.gov (United States)

Singla, V.; Mukherjee, S.; Safai, P. D.; Meena, G. S.; Dani, K. K.; Pandithurai, G.

2017-06-01

The cloud condensation nuclei (CCN) closure study was performed to exemplify the effect of aerosol chemical composition on the CCN activity of aerosols at Mahabaleshwar, a high altitude background site in the Western Ghats, India. For this, collocated aerosol, CCN, Elemental Carbon (EC), Organic Carbon (OC), sub-micron aerosol chemical speciation for the period from 3rd June to 19th June 2015 was used. The chemical composition of non-refractory particulate matter (theory on the basis of measured aerosol particle number size distribution, size independent NR-PM1 chemical composition and calculated hygroscopicity. The CCN closure study was evaluated for 3 scenarios, B-I (all soluble inorganics), B-IO (all soluble organics and inorganics) and B-IOOA (all soluble inorganic and soluble oxygenated organic aerosol, OOA). OOA component was derived from the positive matrix factorization (PMF) analysis of organic aerosol mass spectra. Considering the bulk composition as internal mixture, CCN closure study was underestimated by 16-39% for B-I and overestimated by 47-62% for B-IO. The CCN closure result was appreciably improved for B-IOOA where the knowledge of OOA fraction was introduced and uncertainty reduced to within 8-10%.

Classifying organic materials by oxygen-to-carbon elemental ratio to predict the activation regime of Cloud Condensation Nuclei (CCN

Directory of Open Access Journals (Sweden)

M. Kuwata

2013-05-01

Full Text Available The governing highly soluble, slightly soluble, or insoluble activation regime of organic compounds as cloud condensation nuclei (CCN was examined as a function of oxygen-to-carbon elemental ratio (O : C. New data were collected for adipic, pimelic, suberic, azelaic, and pinonic acids. Secondary organic materials (SOMs produced by α-pinene ozonolysis and isoprene photo-oxidation were also included in the analysis. The saturation concentrations C of the organic compounds in aqueous solutions served as the key parameter for delineating regimes of CCN activation, and the values of C were tightly correlated to the O : C ratios. The highly soluble, slightly soluble, and insoluble regimes of CCN activation were found to correspond to ranges of [O : C] > 0.6, 0.2 < [O : C] < 0.6, and [O : C] < 0.2, respectively. These classifications were evaluated against CCN activation data of isoprene-derived SOM (O : C = 0.69–0.72 and α-pinene-derived SOM (O : C = 0.38–0.48. Isoprene-derived SOM had highly soluble activation behavior, consistent with its high O : C ratio. For α-pinene-derived SOM, although CCN activation can be modeled as a highly soluble mechanism, this behavior was not predicted by the O : C ratio, for which a slightly soluble mechanism was anticipated. Complexity in chemical composition, resulting in continuous water uptake and the absence of a deliquescence transition that can thermodynamically limit CCN activation, might explain the difference in the behavior of α-pinene-derived SOM compared to that of pure organic compounds. The present results suggest that atmospheric particles dominated by hydrocarbon-like organic components do not activate (i.e., insoluble regime whereas those dominated by oxygenated organic components activate (i.e., highly soluble regime for typical atmospheric cloud life cycles.

Molecular regulation of CCN2 in the intervertebral disc: lessons learned from other connective tissues.

Science.gov (United States)

Tran, Cassie M; Shapiro, Irving M; Risbud, Makarand V

2013-08-08

Connective tissue growth factor (CCN2/CTGF) plays an important role in extracellular matrix synthesis, especially in skeletal tissues such as cartilage, bone, and the intervertebral disc. As a result there is a growing interest in examining the function and regulation of this important molecule in the disc. This review discusses the regulation of CCN2 by TGF-β and hypoxia, two critical determinants that characterize the disc microenvironment, and discusses known functions of CCN2 in the disc. The almost ubiquitous regulation of CCN2 by TGF-β, including that seen in the disc, emphasizes the importance of the TGF-β-CCN2 relationship, especially in terms of extracellular matrix synthesis. Likewise, the unique cross-talk between CCN2 and HIF-1 in the disc highlights the tissue and niche specific mode of regulation. Taken together the current literature supports an anabolic role for CCN2 in the disc and its involvement in the maintenance of tissue homeostasis during both health and disease. Further studies of CCN2 in this tissue may reveal valuable targets for the biological therapy of disc degeneration. © 2013 Elsevier B.V. All rights reserved.

On the effects of organic matter and sulphur-containing compounds on the CCN activation of combustion particles

Directory of Open Access Journals (Sweden)

A. Petzold

2005-01-01

Full Text Available The European PartEmis project (Measurement and prediction of emissions of aerosols and gaseous precursors from gas turbine engines was focussed on the characterisation and quantification of exhaust emissions from a gas turbine engine. The combustion aerosol characterisation included on-line measurements of mass and number concentration, size distribution, mixing state, thermal stability of internally mixed particles, hygroscopicity, cloud condensation nuclei (CCN activation potential, and off-line analysis of chemical composition. Based on this extensive data set, the role of sulphuric acid coating and of the organic fraction of the combustion particles for the CCN activation was investigated. Modelling of CCN activation was conducted using microphysical and chemical properties obtained from the measurements as input data. Coating the combustion particles with water-soluble sulphuric acid, increases the potential CCN activation, or lowers the activation diameter, respectively. The adaptation of a Köhler model to the experimental data yielded coatings from 0.1 to 3 vol-% of water-soluble matter, which corresponds to an increase in the fraction of CCN-activated combustion particles from ≤10−4 to ≌10−2 at a water vapour saturation ratio Sw=1.006. Additional particle coating by coagulation of combustion particles and aqueous sulphuric acid particles formed by nucleation further reduces the CCN activation diameter. In contrast, particles containing a large fraction of non-volatile organic compounds grow significantly less at high relative humidity than particles with a lower content of non-volatile OC. The resulting reduction in the potential CCN activation with an increasing fraction of non-volatile OC becomes visible as a trend in the experimental data. While a coating of water-soluble sulphuric acid increases the potential CCN activation, or lowers the activation diameter, respectively, the non-volatile organic compounds, mainly found at

Influences of aerosol physiochemical properties and new particle formation on CCN activity from observation at a suburban site of China

Science.gov (United States)

Li, Yanan; Zhang, Fang; Li, Zhanqing; Sun, Li; Wang, Zhenzhu; Li, Ping; Sun, Yele; Ren, Jingye; Wang, Yuying; Cribb, Maureen; Yuan, Cheng

2017-05-01

With the aim of understanding the impact of aerosol particle size and chemical composition on CCN activity, the size-resolved cloud condensation nuclei (CCN) number concentration (NCCN), particle number size distribution (PSD) (10-600 nm), and bulk chemical composition of particles with a diameter China, from 22 July to 26 August 2014. The NCCN was measured at five different supersaturations (SS) ranging from 0.075%-0.76%. Diurnal variations in the aerosol number concentration (NCN), NCCN, the bulk aerosol activation ratio (AR), the hygroscopicity parameter (κchem), and the ratio of 44 mass to charge ration (m/z 44) to total organic signal in the component spectrum (f44), and the PSD were examined integrally to study the influence of particle size and chemical composition on CCN activation. We found that particle size was more related to the CCN activation ratios in the morning, whereas in the afternoon ( 1400 LST), κchem and f44 were more closely associated with the bulk AR. Assuming the internal mixing of aerosol particles, NCCN was estimated using the bulk chemical composition and real-time PSD. We found that the predicted CCN number concentrations were underestimated by 20-30% at SS case during non-NPF event. It has been found that CCN activation was restrained at the ;growth; stage during which larger particle diameters were needed to reach an activation diameter(Da), and the bulk AR decreased as well. However, during the ;leveling-off; stage, a lower Da was observed and CCN activation was greatly enhanced.

Differentiation of Ecuadorian National and CCN-51 cocoa beans and their mixtures by computer vision.

Science.gov (United States)

Jimenez, Juan C; Amores, Freddy M; Solórzano, Eddyn G; Rodríguez, Gladys A; La Mantia, Alessandro; Blasi, Paolo; Loor, Rey G

2018-05-01

Ecuador exports two major types of cocoa beans, the highly regarded and lucrative National, known for its fine aroma, and the CCN-51 clone type, used in bulk for mass chocolate products. In order to discourage exportation of National cocoa adulterated with CCN-51, a fast and objective methodology for distinguishing between the two types of cocoa beans is needed. This study reports a methodology based on computer vision, which makes it possible to recognize these beans and determine the percentage of their mixture. The methodology was challenged with 336 samples of National cocoa and 127 of CCN-51. By excluding the samples with a low fermentation level and white beans, the model discriminated with a precision higher than 98%. The model was also able to identify and quantify adulterations in 75 export batches of National cocoa and separate out poorly fermented beans. A scientifically reliable methodology able to discriminate between Ecuadorian National and CCN-51 cocoa beans and their mixtures was successfully developed. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Empirical estimates of CCN from aerosol optical properties at four remote sites

Directory of Open Access Journals (Sweden)

A. Jefferson

2010-07-01

Full Text Available This study presents an empirical method to estimate the CCN concentration as a function of percent supersaturation. The aerosol optical properties, backscatter fraction and single scatter albedo, function as proxies for the aerosol size and composition in a power law relationship to CCN. This method is tested at four sites with aged aerosol: SGP (Oklahoma, USA, FKB (Black Forest, Germany, HFE (Hefei, China and GRW (Graciosa, Azores. Each site represents a different aerosol type and thus demonstrates the method robustness and limitations. Good agreement was found between the calculated and measured CCN with slopes between 0.81 and 1.03 and correlation coefficients (r² values between 0.59 and 0.67. The fit quality declined at low CCN concentrations.

Connective tissue growth factor/CCN2-null mouse embryonic fibroblasts retain intact transforming growth factor-β responsiveness

International Nuclear Information System (INIS)

Mori, Yasuji; Hinchcliff, Monique; Wu, Minghua; Warner-Blankenship, Matthew; Lyons, Karen M.; Varga, John

2008-01-01

Background: The matricellular protein connective tissue growth factor (CCN2) has been implicated in pathological fibrosis, but its physiologic role remains elusive. In vitro, transforming growth factor-β (TGF-β) induces CCN2 expression in mesenchymal cells. Because CCN2 can enhance profibrotic responses elicited by TGF-β, it has been proposed that CCN2 functions as an essential downstream signaling mediator for TGF-β. To explore this notion, we characterized TGF-β-induced activation of fibroblasts from CCN2-null (CCN2 -/- ) mouse embryos. Methods: The regulation of CCN2 expression was examined in vivo in a model of fibrosis induced by bleomycin. Cellular TGF-β signal transduction and regulation of collagen gene expression were examined in CCN2 -/- MEFs by immunohistochemistry, Northern, Western and RT-PCR analysis, immunocytochemistry and transient transfection assays. Results: Bleomycin-induced skin fibrosis in the mouse was associated with substantial CCN2 up-regulation in lesional fibroblasts. Whereas in vitro proliferation rate of CCN2 -/- MEFs was markedly reduced compared to wild type MEFs, TGF-β-induced activation of the Smad pathways, including Smad2 phosphorylation, Smad2/3 and Smad4 nuclear accumulation and Smad-dependent transcriptional responses, were unaffected by loss of CCN2. The stimulation of COL1A2 and fibronectin mRNA expression and promoter activity, and of corresponding protein levels, showed comparable time and dose-response in wild type and CCN2 -/- MEFs, whereas stimulation of alpha smooth muscle actin and myofibroblast transdifferentiation showed subtle impairment in MEFs lacking CCN2. Conclusion: Whereas endogenous CCN2 plays a role in regulation of proliferation and TGF-β-induced myofibroblast transdifferentiation, it appears to be dispensable for Smad-dependent stimulation of collagen and extracellular matrix synthesis in murine embryonic fibroblasts

A potential role for CCN2/CTGF in aggressive colorectal cancer

NARCIS (Netherlands)

Ubink, Inge; Verhaar, Elisha R; Kranenburg, Onno; Goldschmeding, Roel

CCN2, also known as connective tissue growth factor (CTGF) is a transcriptional target of TGF-β signaling. Unlike its original name ("CTGF") suggested, CCN2 is not an actual growth factor but a matricellular protein that plays an important role in fibrosis, inflammation and connective tissue

Impaired intervertebral disc development and premature disc degeneration in mice with notochord-specific deletion of CCN2.

Science.gov (United States)

Bedore, Jake; Sha, Wei; McCann, Matthew R; Liu, Shangxi; Leask, Andrew; Séguin, Cheryle A

2013-10-01

Currently, our ability to treat intervertebral disc (IVD) degeneration is hampered by an incomplete understanding of disc development and aging. The specific function of matricellular proteins, including CCN2, during these processes remains an enigma. The aim of this study was to determine the tissue-specific localization of CCN proteins and to characterize their role in IVD tissues during embryonic development and age-related degeneration by using a mouse model of notochord-specific CCN2 deletion. Expression of CCN proteins was assessed in IVD tissues from wild-type mice beginning on embryonic day 15.5 to 17 months of age. Given the enrichment of CCN2 in notochord-derived tissues, we generated notochord-specific CCN2-null mice to assess the impact on the IVD structure and extracellular matrix composition. Using a combination of histologic evaluation and magnetic resonance imaging (MRI), IVD health was assessed. Loss of the CCN2 gene in notochord-derived cells disrupted the formation of IVDs in embryonic and newborn mice, resulting in decreased levels of aggrecan and type II collagen and concomitantly increased levels of type I collagen within the nucleus pulposus. CCN2-knockout mice also had altered expression of CCN1 (Cyr61) and CCN3 (Nov). Mirroring its role during early development, notochord-specific CCN2 deletion accelerated age-associated degeneration of IVDs. Using a notochord-specific gene targeting strategy, this study demonstrates that CCN2 expression by nucleus pulposus cells is essential to the regulation of IVD development and age-associated tissue maintenance. The ability of CCN2 to regulate the composition of the intervertebral disc suggests that it may represent an intriguing clinical target for the treatment of disc degeneration. Copyright © 2013 by the American College of Rheumatology.

CCN2 is required for the TGF-β induced activation of Smad1-Erk1/2 signaling network.

Directory of Open Access Journals (Sweden)

Sashidhar S Nakerakanti

Full Text Available Connective tissue growth factor (CCN2 is a multifunctional matricellular protein, which is frequently overexpressed during organ fibrosis. CCN2 is a mediator of the pro-fibrotic effects of TGF-β in cultured cells, but the specific function of CCN2 in the fibrotic process has not been elucidated. In this study we characterized the CCN2-dependent signaling pathways that are required for the TGF-β induced fibrogenic response. By depleting endogenous CCN2 we show that CCN2 is indispensable for the TGF-β-induced phosphorylation of Smad1 and Erk1/2, but it is unnecessary for the activation of Smad3. TGF-β stimulation triggered formation of the CCN2/β(3 integrin protein complexes and activation of Src signaling. Furthermore, we demonstrated that signaling through the α(vβ(3 integrin receptor and Src was required for the TGF-β induced Smad1 phosphorylation. Recombinant CCN2 activated Src and Erk1/2 signaling, and induced phosphorylation of Fli1, but was unable to stimulate Smad1 or Smad3 phosphorylation. Additional experiments were performed to investigate the role of CCN2 in collagen production. Consistent with the previous studies, blockade of CCN2 abrogated TGF-β-induced collagen mRNA and protein levels. Recombinant CCN2 potently stimulated collagen mRNA levels and upregulated activity of the COL1A2 promoter, however CCN2 was a weak inducer of collagen protein levels. CCN2 stimulation of collagen was dose-dependent with the lower doses (<50 ng/ml having a stimulatory effect and higher doses having an inhibitory effect on collagen gene expression. In conclusion, our study defines a novel CCN2/α(vβ(3 integrin/Src/Smad1 axis that contributes to the pro-fibrotic TGF-β signaling and suggests that blockade of this pathway may be beneficial for the treatment of fibrosis.

A structural approach to the role of CCN (CYR61/CTGF/NOV proteins in tumourigenesis

Directory of Open Access Journals (Sweden)

Perbal Bernard

2003-08-01

Full Text Available Abstract The CCN (CYR61 [Cystein-rich61]/CTGF [connective tissue growth factor]/NOV [Nephroblastoma overexpressed] proteins constitute a family of regulatory factors involved in many aspects of cell proliferation and differentiation. An increasing body of evidence indicates that abnormal expression of the CCN proteins is associated to tumourgenesis. The multimodular architecture of the CCN proteins, and the production of truncated isoforms in tumours, raise interesting questions regarding the participation of each individual module to the various biological properties of these proteins. In this article, we review the current data regarding the involvement of CCN proteins in tumourigenesis. We also attempt to provide structural basis for the stimulatory and inhibitory functions of the full length and truncated CCN proteins that are expressed in various tumour tissues.

CCN5 modulates the antiproliferative effect of heparin and regulates cell motility in vascular smooth muscle cells

Directory of Open Access Journals (Sweden)

Castellot John J

2003-11-01

Full Text Available Abstract Background Vascular smooth muscle cell (VSMC hyperplasia plays an important role in both chronic and acute vascular pathologies including atherosclerosis and restenosis. Considerable work has focused on the mechanisms regulating VSMC proliferation and motility. Earlier work in our lab revealed a novel growth arrest-specific (gas gene induced in VSMC exposed to the antiproliferative agent heparin. This gene is a member of the CCN family and has been given the name CCN5. The objective of the present study is to elucidate the function of CCN5 protein and to explore its mechanism of action in VSMC. Results Using RNA interference (RNAi, we first demonstrate that CCN5 is required for the antiproliferative effect of heparin in VSMC. We also use this gene knockdown approach to show that CCN5 is an important negative regulator of motility. To explore the mechanism of action of CCN5 on VSMC motility, we use RNAi to demonstrate that knock down of CCN5 up regulates expression of matrix metalloproteinase-2 (MMP-2, an important stimulator of motility in VSMC. In addition, forced expression of CCN5 via adenovirus results in reduced MMP-2 activity, this also corroborates the gene knock down results. Finally, we show that loss of CCN5 expression in VSMC causes changes in VSMC morphology and cytoskeletal organization, including a reduction in the amount and macromolecular assembly of smooth muscle cell α-actin. Conclusions This work provides important new insights into the regulation of smooth muscle cell proliferation and motility by CCN5 and may aid the development of therapies for vascular diseases.

Polarimetric radar convective cell tracking reveals large sensitivity of cloud precipitation and electrification properties to CCN

Science.gov (United States)

Hu, J.; Rosenfeld, D.; Zhang, P.; Snyder, J.; Orville, R. E.; Ryzhkov, A.; Zrnic, D.; Williams, E. R.; Zhang, R.

2017-12-01

Here we apply the cell tracking methodology, shown in our companion poster, to quantifying factors affecting the vigor and the time-height evolution of hydrometeors and electrification properties of convective cells. Benefitting from the Dual-polarimetric NEXRAD radar network, we composite more than 5000 well-tracked cells among three radars (at Houston, Lubbock and Oklahoma City), stratified by CCN, CAPE and land/sea locations. The analyzed cell properties include Z, ZDR, Kdp, and ρhv, Dm (raindrop diameter) and Nw (raindrop concentration) by the algorithm of Bringi et al. (2003). Lightning Mapping Array (LMA) data is also included in the analysis, which provides a 3D structure of lightning occurrence and RF power. The contrasting CCN conditions over marine, land, pristine and polluted areas are identified based on the satellite retrieval technique described in Rosenfeld et al. (2016). The results show that more CCN are associated with: Increased echo top height, manifesting the invigoration effect. Enhanced reflectivities, especially above the freezing level at around 4.5 km. Raindrop sizes at the initial stage increase at the expense of their concentrations, due to the smaller cloud droplets and suppressed coalescence. Larger propensity for hail. Lightning sources increase with greater CCN concentration and is likely due to the delayed warm rain process and enhanced mixed phase process under more CCN condition, when activated CCN into cloud droplets is too high (> 1000 cm-3) the glaciation is delayed too much and leave little ice at lower levels and thus decrease lightning activity. Land pristine clouds have fewer lightning sources than polluted clouds. Marine pristine clouds seldom have lightning Increased CAPE had a similar effect to the effect of added CCN. The cloud tracking and properties are obtained by a new methodology of Multi-Cell Identification and Tracking (MCIT) algorithm (Hu et al, 2017), with details about the algorithm to be found in the author

Renner-Teller effects in the photoelectron spectra of CNC, CCN, and HCCN.

Science.gov (United States)

Coudert, Laurent H; Gans, Bérenger; Garcia, Gustavo A; Loison, Jean-Christophe

2018-02-07

The line intensity of photoelectron spectra when either the neutral or cationic species display a Renner-Teller coupling is derived and applied to the modeling of the photoelectron spectra of CNC, CCN, and HCCN. The rovibronic energy levels of these three radicals and of their cations are investigated starting from ab initio results. A model treating simultaneously the bending mode and the overall rotation is developed to deal with the quasilinearity problem in CNC + , CCN + , and HCCN and accounts for the large amplitude nature of their bending mode. This model is extended to treat the Renner-Teller coupling in CNC, CCN, and HCCN + . Based on the derived photoelectron line intensity, the photoelectron spectra of all three molecules are calculated and compared to the experimental ones.

Exploring the relationship between a ground-based network and airborne CCN spectra observed at the cloud level

Science.gov (United States)

Corrigan, C.; Roberts, G. C.; Ritchie, J.; Creamean, J.; White, A. B.

2011-12-01

Cloud condensation nuclei (CCN) are aerosol particles that participate in the formation of clouds, and consequently, play a significant role in the influence of anthropogenic aerosols on atmospheric processes and climate change. Ultimately, the CCN of the most interest occupy the part of the atmosphere where cloud processes are occurring. A question arises as to whether in-cloud CCN are properly represented by the measurements of CCN at the ground level. While different locations may result in different answers depending upon local meteorology, the data set collected during CalWater 2011 may allow us to answer to what degree the ground-based observations of CCN are sufficient for evaluating cloud micro-physics over California's Central Valley and the lower slopes of the Sierra Nevada Mountains. During CalWater 2011, ground observations were performed at three different altitudes to assess the evolution of cloud-active aerosols as they were transported from sources in California's Central Valley to the lower slopes of the Sierra Nevada Mountains. CCN spectra were collected over a supersaturation range of 0.08 to 0.80%. Results from these data sets show a diurnal cycle with aerosol concentrations increasing during the afternoon and retreating during the night. In addition, a CCN instrument was placed aboard aircraft for several flights and was able to collect vertical profiles that encompassed the altitudes of the ground sites. The flight data shows a large drop in CCN concentration above the boundary layer and suggests the highest altitude ground site at China Wall ( 1540 masl)was sometimes above the Central Valley boundary layer. By using estimates of boundary layer heights over the mid-altitude site at Sugar Pine Dam (1060 masl), the events when the China Wall site is near or above the boundary layer are identified. During these events, the CCN measurements at China Wall best represent in-cloud CCN behavior. The results of this analysis may be applied towards a

Investigation of the CCN Activity, BC and UVBC Mass Concentrations of Biomass Burning Aerosols during the 2013 BASELInE Campaign

Science.gov (United States)

Hsiao, Ta-Chih; Ye, Wei-Cheng; Wang, Sheng-Hsiang; Tsay, Si-Chee; Chen, Wei-Nai; Lin, Neng-Huei; Lee, Chung-Te; Hung, Hui-Ming; Chuang, Ming-Tung; Chantara, Somporn

2015-01-01

Biomass-burning (BB) aerosols, acting as cloud condensation nuclei (CCN), can influence cloud microphysical and radiative properties. In this study, we present CCN measured near the BB source regions over northern Southeast Asia (Doi Ang Khang, Thailand) and at downwind receptor areas (Lulin Atmospheric Background Station, Taiwan), focusing exclusively on 13-20 March 2013 as part of 2013 spring campaign of the Seven SouthEast Asian Studies (7-SEAS) intensive observation. One of the campaigns objectives is to characterize BB aerosols serving as CCN in SouthEast Asia (SEA). CCN concentrations were measured by a CCN counter at 5 supersaturation (SS) levels: 0.15%, 0.30%, 0.45%, 0.60%, and 0.75%. In addition, PM2.5 and black carbon mass concentrations were analyzed by using a tapered element oscillating microbalance and an aethalometer. It was found the number-size distributions and the characteristics of hygroscopicity (e.g., activation ratio and k) of BB aerosols in SEA have a strong diurnal pattern, and different behaviors of patterns were characterized under two distinct weather systems. The overall average value was low (0.05-0.1) but comparable with previous CCN studies in other BB source regions. Furthermore, a large fraction of UV-absorbing organic material (UVBC) and high Delta-C among BB aerosols were also observed, which suggest the existence of substantial particulate organic matter in fresh BB aerosols. These data provide the most extensive characterization of BB aerosols in SEA until now.

CCN activity and droplet growth kinetics of fresh and aged monoterpene secondary organic aerosol

Directory of Open Access Journals (Sweden)

G. J. Engelhart

2008-07-01

Full Text Available The ability of secondary organic aerosol (SOA produced from the ozonolysis of α-pinene and monoterpene mixtures (α-pinene, β-pinene, limonene and 3-carene to become cloud droplets was investigated. A static CCN counter and a Scanning Mobility CCN Analyser (a Scanning Mobility Particle Sizer coupled with a Continuous Flow counter were used for the CCN measurements. Consistent with previous studies monoterpene SOA is quite active and would likely be a good source of cloud condensation nuclei (CCN in the atmosphere. A decrease in CCN activation diameter for α-pinene SOA of approximately 3 nm hr⁻¹ was observed as the aerosol continued to react with oxidants. Hydroxyl radicals further oxidize the SOA particles thereby enhancing the particle CCN activity with time. The initial concentrations of ozone and monoterpene precursor (for concentrations lower than 40 ppb do not appear to affect the activity of the resulting SOA. Köhler Theory Analysis (KTA is used to infer the molar mass of the SOA sampled online and offline from atomized filter samples. The estimated average molar mass of online SOA was determined to be 180±55 g mol⁻¹ (consistent with existing SOA speciation studies assuming complete solubility. KTA suggests that the aged aerosol (both from α-pinene and the mixed monoterpene oxidation is primarily water-soluble (around 65%. CCN activity measurements of the SOA mixed with (NH₄₂SO₄ suggest that the organic can depress surface tension by as much as 10 N m⁻¹ (with respect to pure water. The droplet growth kinetics of SOA samples are similar to (NH₄₂SO₄, except at low supersaturation, where SOA tends to grow more slowly. The CCN activation diameter of α-pinene and mixed monoterpene SOA can be modelled to within 10–15% of experiments by a simple implementation of Köhler theory, assuming complete dissolution of the particles, no

Expression of connective tissue growth factor (CTGF/CCN2) in breast cancer cells is associated with increased migration and angiogenesis.

Science.gov (United States)

Chien, Wenwen; O'Kelly, James; Lu, Daning; Leiter, Amanda; Sohn, Julia; Yin, Dong; Karlan, Beth; Vadgama, Jay; Lyons, Karen M; Koeffler, H Phillip

2011-06-01

Connective tissue growth factor (CTGF/CCN2) belongs to the CCN family of matricellular proteins, comprising Cyr61, CTGF, NovH and WISP1-3. The CCN proteins contain an N-terminal signal peptide followed by four conserved domains sharing sequence similarities with the insulin-like growth factor binding proteins, von Willebrand factor type C repeat, thrombospondin type 1 repeat, and a C-terminal growth factor cysteine knot domain. To investigate the role of CCN2 in breast cancer, we transfected MCF-7 cells with full-length CCN2, and with four mutant constructs in which one of the domains had been deleted. MCF-7 cells stably expressing full-length CCN2 demonstrated reduced cell proliferation, increased migration in Boyden chamber assays and promoted angiogenesis in chorioallantoic membrane assays compared to control cells. Deletion of the C-terminal cysteine knot domain, but not of any other domain-deleted mutants, abolished activities mediated by full-length CCN2. We have dissected the role of CCN2 in breast tumorigenesis on a structural basis.

Cyr61/CCN1 signaling is critical for epithelial-mesenchymal transition and stemness and promotes pancreatic carcinogenesis

Directory of Open Access Journals (Sweden)

Van Veldhuizen Peter J

2011-01-01

Full Text Available Abstract Background Despite recent advances in outlining the mechanisms involved in pancreatic carcinogenesis, precise molecular pathways and cellular lineage specification remains incompletely understood. Results We show here that Cyr61/CCN1 play a critical role in pancreatic carcinogenesis through the induction of EMT and stemness. Cyr61 mRNA and protein were detected in the early precursor lesions and their expression intensified with disease progression. Cyr61/CCN1 expression was also detected in different pancreatic cancer cell lines. The aggressive cell lines, in which the expressions of mesenchymal/stem cell molecular markers are predominant; exhibit more Cyr61/CCN1 expression. Cyr61 expression is exorbitantly higher in cancer stem/tumor initiating Panc-1-side-population (SP cells. Upon Cyr61/CCN1 silencing, the aggressive behaviors are reduced by obliterating interlinking pathobiological events such as reversing the EMT, blocking the expression of stem-cell-like traits and inhibiting migration. In contrast, addition of Cyr61 protein in culture medium augments EMT and stemness features in relatively less aggressive BxPC3 pancreatic cancer cells. Using a xenograft model we demonstrated that cyr61/CCN1 silencing in Panc-1-SP cells reverses the stemness features and tumor initiating potency of these cells. Moreover, our results imply a miRNA-based mechanism for the regulation of aggressive behaviors of pancreatic cancer cells by Cyr61/CCN1. Conclusions In conclusion, the discovery of the involvement of Cyr61/CCN1 in pancreatic carcinogenesis may represent an important marker for PDAC and suggests Cyr61/CCN1 can be a potential cancer therapeutic target.

Cyr61/CCN1 induces CCL20 production by keratinocyte via activating p38 and JNK/AP-1 pathway in psoriasis.

Science.gov (United States)

Li, Huidan; Li, Haichuan; Huo, Rongfen; Wu, Pinru; Shen, Zhengyu; Xu, Hui; Shen, Baihua; Li, Ningli

2017-10-01

Psoriasis is a common chronic skin disease characterized by epidermal hyperplasia and inflammation. Cysteine-rich angiogenic inducer 61 (Cyr61/CCN1) has recently been implicated in psoriasis pathogenesis by promoting keratinocyte activation. However, the mechanisms by which CCN1 enhances cutaneous inflammation are not fully understood. In this study, we investigated the role of CCN1 on the expression of CCL20 in human keratinocyte. By double-label immunofluorescence staining, we first identified that the expression of CCN1 colocalized well with CCL20 production in the epidermis of psoriasis skin lesion. Furthermore, in vivo, blocking or knockdown CCN1 expression ameliorated skin inflammation and reduced the expression of CCL20 in both imiquimod and IL-23-induced psoriasis-like mouse models, which indicated that CCN1 might be involved in the regulation of CCL20 production in psoriasis. Next, in vitro, we stimulated primary normal human epidermal keratinocyte (NHEK) with exogenous protein CCN1 and found that CCN1 directly upregulated CCL20 production independent of TNF-α, IL-22 and IL-17 pathway. Lastly, the signaling pathway study showed that CCN1 enhanced the binding of AP-1 to the CCL20 promoter via crosstalk with p38 and JNK. Our study demonstrates that CCN1 stimulates CCL20 production in vitro and in vivo, and thus supports the notion that overexpressed CCN1 in hyperproliferating keratinocyte is functionally involved in the recruitment of inflammatory cells to skin lesions affected by psoriasis. Copyright © 2017 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.

Growth differentiation factor-15 (GDF-15) suppresses in vitro angiogenesis through a novel interaction with connective tissue growth factor (CCN2).

Science.gov (United States)

Whitson, Ramon J; Lucia, Marshall Scott; Lambert, James R

2013-06-01

Growth differentiation factor-15 (GDF-15) and the CCN family member, connective tissue growth factor (CCN2), are associated with cardiac disease, inflammation, and cancer. The precise role and signaling mechanism for these factors in normal and diseased tissues remains elusive. Here we demonstrate an interaction between GDF-15 and CCN2 using yeast two-hybrid assays and have mapped the domain of interaction to the von Willebrand factor type C domain of CCN2. Biochemical pull down assays using secreted GDF-15 and His-tagged CCN2 produced in PC-3 prostate cancer cells confirmed a direct interaction between these proteins. To investigate the functional consequences of this interaction, in vitro angiogenesis assays were performed. We demonstrate that GDF-15 blocks CCN2-mediated tube formation in human umbilical vein endothelial (HUVEC) cells. To examine the molecular mechanism whereby GDF-15 inhibits CCN2-mediated angiogenesis, activation of αV β3 integrins and focal adhesion kinase (FAK) was examined. CCN2-mediated FAK activation was inhibited by GDF-15 and was accompanied by a decrease in αV β3 integrin clustering in HUVEC cells. These results demonstrate, for the first time, a novel signaling pathway for GDF-15 through interaction with the matricellular signaling molecule CCN2. Furthermore, antagonism of CCN2 mediated angiogenesis by GDF-15 may provide insight into the functional role of GDF-15 in disease states. Copyright © 2012 Wiley Periodicals, Inc.

Metrics to quantify the importance of mixing state for CCN activity

Directory of Open Access Journals (Sweden)

J. Ching

2017-06-01

Full Text Available It is commonly assumed that models are more prone to errors in predicted cloud condensation nuclei (CCN concentrations when the aerosol populations are externally mixed. In this work we investigate this assumption by using the mixing state index (χ proposed by Riemer and West (2013 to quantify the degree of external and internal mixing of aerosol populations. We combine this metric with particle-resolved model simulations to quantify error in CCN predictions when mixing state information is neglected, exploring a range of scenarios that cover different conditions of aerosol aging. We show that mixing state information does indeed become unimportant for more internally mixed populations, more precisely for populations with χ larger than 75 %. For more externally mixed populations (χ below 20 % the relationship of χ and the error in CCN predictions is not unique and ranges from lower than −40 % to about 150 %, depending on the underlying aerosol population and the environmental supersaturation. We explain the reasons for this behavior with detailed process analyses.

Development of a cloud microphysical model and parameterizations to describe the effect of CCN on warm cloud

Directory of Open Access Journals (Sweden)

N. Kuba

2006-01-01

Full Text Available First, a hybrid cloud microphysical model was developed that incorporates both Lagrangian and Eulerian frameworks to study quantitatively the effect of cloud condensation nuclei (CCN on the precipitation of warm clouds. A parcel model and a grid model comprise the cloud model. The condensation growth of CCN in each parcel is estimated in a Lagrangian framework. Changes in cloud droplet size distribution arising from condensation and coalescence are calculated on grid points using a two-moment bin method in a semi-Lagrangian framework. Sedimentation and advection are estimated in the Eulerian framework between grid points. Results from the cloud model show that an increase in the number of CCN affects both the amount and the area of precipitation. Additionally, results from the hybrid microphysical model and Kessler's parameterization were compared. Second, new parameterizations were developed that estimate the number and size distribution of cloud droplets given the updraft velocity and the number of CCN. The parameterizations were derived from the results of numerous numerical experiments that used the cloud microphysical parcel model. The input information of CCN for these parameterizations is only several values of CCN spectrum (they are given by CCN counter for example. It is more convenient than conventional parameterizations those need values concerned with CCN spectrum, C and k in the equation of N=CSk, or, breadth, total number and median radius, for example. The new parameterizations' predictions of initial cloud droplet size distribution for the bin method were verified by using the aforesaid hybrid microphysical model. The newly developed parameterizations will save computing time, and can effectively approximate components of cloud microphysics in a non-hydrostatic cloud model. The parameterizations are useful not only in the bin method in the regional cloud-resolving model but also both for a two-moment bulk microphysical model and

CCN5 overexpression inhibits profibrotic phenotypes via the PI3K/Akt signaling pathway in lung fibroblasts isolated from patients with idiopathic pulmonary fibrosis and in an in vivo model of lung fibrosis.

Science.gov (United States)

Zhang, Lin; Li, Yingna; Liang, Chunlian; Yang, Weilin

2014-02-01

Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive interstitial lung disease with unknown etiology and undefined treatment modality. Fibroblasts are regarded as the major cell type that mediates the onset and progression of lung fibrosis by secreting large amounts of extracellular matrix (ECM) proteins, such as connective tissue growth factor (CTGF/CCN2). Current knowledge confers a crucial role of CCN2 in lung fibrosis. CCN5, another member of the CCN family, has been suggested to play an inhibitory role in some fibrotic diseases, such as cardiac fibrosis. However, the role of CCN5 in the process of IPF remains unknown. In the present study, using western blot analysis, we demonstrate that CCN2 is highly expressed in fibroblasts derived from IPF tissue, but is only slightly expressed in normal human lung fibroblasts. However, CCN5 was weakly expressed in all the above cells. qRT-PCR revealed that transforming growth factor (TGF)-β1 stimulation increased CCN2 expression in the IPF-derived cultures of primary human lung fibroblasts (PIFs) in a time- and concentration-dependent manner, but only slightly affected the expression of CCN5. The overexpression of CCN5 induced by the transfection of PIFs with recombinant plasmid did not affect cell viability, proliferation and apoptosis; however, it significantly suppressed the expression of CCN2, α-smooth muscle actin (α-SMA) and collagen type I. The TGF-β1-induced upregulation of the phosphorylation of Akt was reversed by CCN5 overexpression. Our results also demonstrated that adenovirus-mediated CCN5 overexpression in a mouse model of bleomycin-induced IPF significantly decreased the hydroxyproline content in the lungs, as well as TGF-β1 expression in bronchoalveolar lavage fluid. Taken together, our data demonstrate that CCN5 exerts an inhibitory effect on the fibrotic phenotypes of pulmonary fibroblasts in vitro and in vivo, and as such may be a promising target for the treatment of IPF.

Plasma CCN2/connective tissue growth factor is associated with right ventricular dysfunction in patients with neuroendocrine tumors

Directory of Open Access Journals (Sweden)

Aakhus Svend

2010-01-01

Full Text Available Abstract Background Carcinoid heart disease, a known complication of neuroendocrine tumors, is characterized by right heart fibrotic lesions. Carcinoid heart disease has traditionally been defined by the degree of valvular involvement. Right ventricular (RV dysfunction due to mural involvement may also be a manifestation. Connective tissue growth factor (CCN2 is elevated in many fibrotic disorders. Its role in carcinoid heart disease is unknown. We sought to investigate the relationship between plasma CCN2 and valvular and mural involvement in carcinoid heart disease. Methods Echocardiography was performed in 69 patients with neuroendocrine tumors. RV function was assessed using tissue Doppler analysis of myocardial systolic strain. Plasma CCN2 was analyzed using an enzyme-linked immunosorbent assay. Mann-Whitney U, Kruskal-Wallis, Chi-squared and Fisher's exact tests were used to compare groups where appropriate. Linear regression was used to evaluate correlation. Results Mean strain was -21% ± 5. Thirty-three patients had reduced RV function (strain > -20%, mean -16% ± 3. Of these, 8 had no or minimal tricuspid and/or pulmonary regurgitation (TR/PR. Thirty-six patients had normal or mildly reduced RV function (strain ≤ -20%, mean -25% ± 3. There was a significant inverse correlation between RV function and plasma CCN2 levels (r = 0.47, p Conclusions Elevated plasma CCN2 levels are associated with RV dysfunction and valvular regurgitation in NET patients. CCN2 may play a role in neuroendocrine tumor-related cardiac fibrosis and may serve as a marker of its earliest stages.

Inverse modelling of Köhler theory – Part 1: A response surface analysis of CCN spectra with respect to surface-active organic species

Directory of Open Access Journals (Sweden)

S. Lowe

2016-09-01

Full Text Available In this study a novel framework for inverse modelling of cloud condensation nuclei (CCN spectra is developed using Köhler theory. The framework is established by using model-generated synthetic measurements as calibration data for a parametric sensitivity analysis. Assessment of the relative importance of aerosol physicochemical parameters, while accounting for bulk–surface partitioning of surface-active organic species, is carried out over a range of atmospherically relevant supersaturations. By introducing an objective function that provides a scalar metric for diagnosing the deviation of modelled CCN concentrations from synthetic observations, objective function response surfaces are presented as a function of model input parameters. Crucially, for the chosen calibration data, aerosol–CCN spectrum closure is confirmed as a well-posed inverse modelling exercise for a subset of the parameters explored herein. The response surface analysis indicates that the appointment of appropriate calibration data is particularly important. To perform an inverse aerosol–CCN closure analysis and constrain parametric uncertainties, it is shown that a high-resolution CCN spectrum definition of the calibration data is required where single-valued definitions may be expected to fail. Using Köhler theory to model CCN concentrations requires knowledge of many physicochemical parameters, some of which are difficult to measure in situ on the scale of interest and introduce a considerable amount of parametric uncertainty to model predictions. For all partitioning schemes and environments modelled, model output showed significant sensitivity to perturbations in aerosol log-normal parameters describing the accumulation mode, surface tension, organic : inorganic mass ratio, insoluble fraction, and solution ideality. Many response surfaces pertaining to these parameters contain well-defined minima and are therefore good candidates for calibration using a Monte

Long-term observations of cloud condensation nuclei in the Amazon rain forest – Part 1: Aerosol size distribution, hygroscopicity, and new model parametrizations for CCN prediction

Directory of Open Access Journals (Sweden)

M. L. Pöhlker

2016-12-01

Full Text Available Size-resolved long-term measurements of atmospheric aerosol and cloud condensation nuclei (CCN concentrations and hygroscopicity were conducted at the remote Amazon Tall Tower Observatory (ATTO in the central Amazon Basin over a 1-year period and full seasonal cycle (March 2014–February 2015. The measurements provide a climatology of CCN properties characteristic of a remote central Amazonian rain forest site.The CCN measurements were continuously cycled through 10 levels of supersaturation (S  =  0.11 to 1.10 % and span the aerosol particle size range from 20 to 245 nm. The mean critical diameters of CCN activation range from 43 nm at S  =  1.10 % to 172 nm at S  =  0.11 %. The particle hygroscopicity exhibits a pronounced size dependence with lower values for the Aitken mode (κAit  =  0.14 ± 0.03, higher values for the accumulation mode (κAcc  =  0.22 ± 0.05, and an overall mean value of κmean  =  0.17 ± 0.06, consistent with high fractions of organic aerosol.The hygroscopicity parameter, κ, exhibits remarkably little temporal variability: no pronounced diurnal cycles, only weak seasonal trends, and few short-term variations during long-range transport events. In contrast, the CCN number concentrations exhibit a pronounced seasonal cycle, tracking the pollution-related seasonality in total aerosol concentration. We find that the variability in the CCN concentrations in the central Amazon is mostly driven by aerosol particle number concentration and size distribution, while variations in aerosol hygroscopicity and chemical composition matter only during a few episodes.For modeling purposes, we compare different approaches of predicting CCN number concentration and present a novel parametrization, which allows accurate CCN predictions based on a small set of input data.

The Cloud Condensation Nuclei (CCN properties of 2-methyltetrols and C3-C6 polyols from osmolality and surface tension measurements

Directory of Open Access Journals (Sweden)

S. Ekström

2009-02-01

Full Text Available A significant fraction of the organic material in aerosols is made of highly soluble compounds such as sugars (mono- and polysaccharides and polyols such as the 2-methyltetrols, methylerythritol and methyltreitol. Because of their high solubility these compounds are considered as potentially efficient CCN material. For the 2-methyltetrols, this would have important implications for cloud formation at global scale because they are thought to be produced by the atmospheric oxidation of isoprene. To investigate this question, the complete Köhler curves for C3-C6 polyols and the 2-methyltetrols have been determined experimentally from osmolality and surface tension measurements. Contrary to what was expected, none of these compounds displayed a higher CCN efficiency than organic acids. Their Raoult terms show that this limited CCN efficiency is due to their absence of dissociation in water, this in spite of slight surface-tension effects for the 2-methyltetrols. Thus, compounds such as saccharides and polyols would not contribute more to cloud formation than other organic compounds studied so far. In particular, the presence of 2-methyltetrols in aerosols would not particularly enhance cloud formation in the atmosphere, in contrary to recently suggested.

Free troposphere as a major source of CCN for the equatorial pacific boundary layer: long-range transport and teleconnections

Directory of Open Access Journals (Sweden)

A. D. Clarke

2013-08-01

Full Text Available Airborne aerosol measurements in the central equatorial Pacific during PASE (Pacific Atmospheric Sulfur Experiment revealed that cloud condensation nuclei (CCN activated in marine boundary layer (MBL clouds were strongly influenced by entrainment from the free troposphere (FT. About 65% entered at sizes effective as CCN in MBL clouds, while ~25% entered the MBL too small to activate but subsequently grew via gas to particle conversion. The remaining ~10% were inferred to be sea salt aerosol. FT aerosols at low carbon monoxide (CO mixing ratios ( The observed FT transport over thousands of kilometers indicates teleconnections between MBL CCN and cloud-scavenged sources of both natural and/or residual combustion origin. Nonetheless, in spite of its importance, this source of CCN number is not well represented in most current models and is generally not detectable by satellite because of the low aerosol scattering in such layers as a result of cloud scavenging. In addition, our measurements confirm nucleation in the MBL was not evident during PASE and argue against a localized linear relation in the MBL between dimethyl sulfide (DMS and CCN suggested by the CLAW hypothesis. However, when the FT is not impacted by long-range transport, sulfate aerosol derived from DMS pumped aloft in the ITCZ (Inter-Tropical Convergence Zone can provide a source of CCN to the boundary layer via FT teleconnections involving more complex non-linear processes.

Droplet number uncertainties associated with CCN: an assessment using observations and a global model adjoint

Directory of Open Access Journals (Sweden)

R. H. Moore

2013-04-01

Full Text Available We use the Global Modelling Initiative (GMI chemical transport model with a cloud droplet parameterisation adjoint to quantify the sensitivity of cloud droplet number concentration to uncertainties in predicting CCN concentrations. Published CCN closure uncertainties for six different sets of simplifying compositional and mixing state assumptions are used as proxies for modelled CCN uncertainty arising from application of those scenarios. It is found that cloud droplet number concentrations (Nd are fairly insensitive to the number concentration (Na of aerosol which act as CCN over the continents (∂lnNd/∂lnNa ~10–30%, but the sensitivities exceed 70% in pristine regions such as the Alaskan Arctic and remote oceans. This means that CCN concentration uncertainties of 4–71% translate into only 1–23% uncertainty in cloud droplet number, on average. Since most of the anthropogenic indirect forcing is concentrated over the continents, this work shows that the application of Köhler theory and attendant simplifying assumptions in models is not a major source of uncertainty in predicting cloud droplet number or anthropogenic aerosol indirect forcing for the liquid, stratiform clouds simulated in these models. However, it does highlight the sensitivity of some remote areas to pollution brought into the region via long-range transport (e.g., biomass burning or from seasonal biogenic sources (e.g., phytoplankton as a source of dimethylsulfide in the southern oceans. Since these transient processes are not captured well by the climatological emissions inventories employed by current large-scale models, the uncertainties in aerosol-cloud interactions during these events could be much larger than those uncovered here. This finding motivates additional measurements in these pristine regions, for which few observations exist, to quantify the impact (and associated uncertainty of transient aerosol processes on cloud properties.

CCN Properties of Organic Aerosol Collected Below and within Marine Stratocumulus Clouds near Monterey, California

Directory of Open Access Journals (Sweden)

Akua Asa-Awuku

2015-10-01

Full Text Available The composition of aerosol from cloud droplets differs from that below cloud. Its implications for the Cloud Condensation Nuclei (CCN activity are the focus of this study. Water-soluble organic matter from below cloud, and cloud droplet residuals off the coast of Monterey, California were collected; offline chemical composition, CCN activity and surface tension measurements coupled with Köhler Theory Analysis are used to infer the molar volume and surfactant characteristics of organics in both samples. Based on the surface tension depression of the samples, it is unlikely that the aerosol contains strong surfactants. The activation kinetics for all samples examined are consistent with rapid (NH42SO4 calibration aerosol. This is consistent with our current understanding of droplet kinetics for ambient CCN. However, the carbonaceous material in cloud drop residuals is far more hygroscopic than in sub-cloud aerosol, suggestive of the impact of cloud chemistry on the hygroscopic properties of organic matter.

Oxidative stress and CCN1 protein in human skin connective tissue aging

Directory of Open Access Journals (Sweden)

Zhaoping Qin

2016-06-01

Full Text Available Reactive oxygen species (ROS is an important pathogenic factor involved in human aging. Human skin is a primary target of oxidative stress from ROS generated from both extrinsic and intrinsic sources, like ultraviolet irradiation (UV and endogenous oxidative metabolism. Oxidative stress causes the alterations of collagen-rich extracellular matrix (ECM, the hallmark of skin connective tissue aging. Age-related alteration of dermal collagenous ECM impairs skin structural integrity and creates a tissue microenvironment that promotes age-related skin diseases, such as poor wound healing and skin cancer. Here, we review recent advances in our understanding of oxidative stress and CCN1 protein (first member of CCN family proteins, a critical mediator of oxidative stress-induced skin connective tissue aging.

The anti-fibrotic effects of CCN1/CYR61 in primary portal myofibroblasts are mediated through induction of reactive oxygen species resulting in cellular senescence, apoptosis and attenuated TGF-β signaling.

Science.gov (United States)

Borkham-Kamphorst, Erawan; Schaffrath, Christian; Van de Leur, Eddy; Haas, Ute; Tihaa, Lidia; Meurer, Steffen K; Nevzorova, Yulia A; Liedtke, Christian; Weiskirchen, Ralf

2014-05-01

Cysteine-rich protein 61 (CCN1/CYR61) is a CCN (CYR61, CTGF (connective tissue growth factor), and NOV (Nephroblastoma overexpressed gene)) family matricellular protein comprising six secreted CCN proteins in mammals. CCN1/CYR61 expression is associated with inflammation and injury repair. Recent studies show that CCN1/CYR61 limits fibrosis in models of cutaneous wound healing by inducing cellular senescence in myofibroblasts of the granulation tissue which thereby transforms into an extracellular matrix-degrading phenotype. We here investigate CCN1/CYR61 expression in primary profibrogenic liver cells (i.e., hepatic stellate cells and periportal myofibroblasts) and found an increase of CCN1/CYR61 expression during early activation of hepatic stellate cells that declines in fully transdifferentiated myofibroblasts. By contrast, CCN1/CYR61 levels found in primary parenchymal liver cells (i.e., hepatocytes) were relatively low compared to the levels exhibited in hepatic stellate cells and portal myofibroblasts. In models of ongoing liver fibrogenesis, elevated levels of CCN1/CYR61 were particularly noticed during early periods of insult, while expression declined during prolonged phases of fibrogenesis. We generated an adenovirus type 5 encoding CCN1/CYR61 (i.e., Ad5-CMV-CCN1/CYR61) and overexpressed CCN1/CYR61 in primary portal myofibroblasts. Interestingly, overexpressed CCN1/CYR61 significantly inhibited production of collagen type I at both mRNA and protein levels as evidenced by quantitative real-time polymerase chain reaction, Western blot and immunocytochemistry. CCN1/CYR61 further induces production of reactive oxygen species (ROS) leading to dose-dependent cellular senescence and apoptosis. Additionally, we demonstrate that CCN1/CYR61 attenuates TGF-β signaling by scavenging TGF-β thereby mitigating in vivo liver fibrogenesis in a bile duct ligation model. In line with dermal fibrosis and scar formation, CCN1/CYR61 is involved in liver injury repair and

Aerosol properties and their impacts on surface CCN at the ARM Southern Great Plains site during the 2011 Midlatitude Continental Convective Clouds Experiment

Science.gov (United States)

Logan, Timothy; Dong, Xiquan; Xi, Baike

2018-02-01

Aerosol particles are of particular importance because of their impacts on cloud development and precipitation processes over land and ocean. Aerosol properties as well as meteorological observations from the Department of Energy Atmospheric Radiation Measurement (ARM) platform situated in the Southern Great Plains (SGP) are utilized in this study to illustrate the dependence of continental cloud condensation nuclei (CCN) number concentration ( N CCN) on aerosol type and transport pathways. ARM-SGP observations from the 2011 Midlatitude Continental Convective Clouds Experiment field campaign are presented in this study and compared with our previous work during the 2009-10 Clouds, Aerosol, and Precipitation in the Marine Boundary Layer field campaign over the current ARM Eastern North Atlantic site. Northerly winds over the SGP reflect clean, continental conditions with aerosol scattering coefficient ( σ sp) values less than 20 Mm-1 and N CCN values less than 100 cm-3. However, southerly winds over the SGP are responsible for the observed moderate to high correlation ( R) among aerosol loading ( σ sp moisture via the Gulf of Mexico, indicating a strong dependence on air mass type. NASA MERRA-2 reanalysis aerosol and chemical data are moderately to highly correlated with surface ARM-SGP data, suggesting that this facility can represent surface aerosol conditions in the SGP, especially during strong aerosol loading events that transport via the Gulf of Mexico. Future long-term investigations will help to understand the seasonal influences of air masses on aerosol, CCN, and cloud properties over land in comparison to over ocean.

Berberine attenuates CCN2-induced IL-1β expression and prevents cartilage degradation in a rat model of osteoarthritis

Energy Technology Data Exchange (ETDEWEB)

Liu, Shan-Chi [Graduate Institute of Basic Medical Science, China Medical University, Taichung, Taiwan (China); Lee, Hsiang-Ping [Graduate Institute of Chinese Medicine, China Medical University, Taichung, Taiwan (China); Department of Chinese Medicine, China Medical University Hospital, Taichung, Taiwan (China); Hung, Chun-Yin [Department of Orthopaedic Surgery, China Medical University Beigang Hospital, Yun-Lin County, Taiwan (China); Tsai, Chun-Hao [Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan (China); Department of Orthopedic Surgery, China Medical University Hospital, Taichung, Taiwan (China); Li, Te-Mao [School of Chinese Medicine, China Medical University, Taichung, Taiwan (China); Tang, Chih-Hsin, E-mail: chtang@mail.cmu.edu.tw [Graduate Institute of Basic Medical Science, China Medical University, Taichung, Taiwan (China); Department of Pharmacology, School of Medicine, China Medical University, Taichung, Taiwan (China); Department of Biotechnology, College of Health Science, Asia University, Taichung, Taiwan (China)

2015-11-15

Connective tissue growth factor (CTGF; also known as CCN2) is an inflammatory mediator that is abundantly expressed in osteoarthritis (OA). Interleukin-1β (IL-1β) plays a pivotal role in OA pathogenesis. Berberine exhibits an anti-inflammatory effect, but the mechanisms by which it modulates CCN2-induced IL-1β expression in OA synovial fibroblasts (OASFs) remain unknown. We showed that CCN2-induced IL-1β expression is mediated by the activation of α{sub v}β{sub 3}/α{sub v}β{sub 5} integrin-dependent reactive oxygen species (ROS) generation, and subsequent activation of apoptosis signal-regulating kinase 1 (ASK1), p38/JNK, and nuclear factor-κB (NF-κB) signaling pathways. This IL-1β expression in OASFs is attenuated by N-acetylcysteine (NAC), inhibitors of ASK1, p38, or JNK, or treatment with berberine. Furthermore, berberine also reverses cartilage damage in an experimental model of collagenase-induced OA (CIOA). We observed that CCN2 increased IL-1β expression via α{sub v}β{sub 3}/α{sub v}β{sub 5} integrins, ROS, and ASK1, p38/JNK, and NF-κB signaling pathways. Berberine was found to inhibit these signaling components in OASFs in vitro and prevent cartilage degradation in vivo. We suggest a novel therapeutic strategy of using berberine for managing OA. - Highlights: • CCN2 induce IL-1β production via αvβ3/αvβ5 integrin, ROS, ASK1, p38/JNK, and NF-κB. • Berberine attenuates CCN2-induced IL-1β expression in vitro and in OA rat model. • Berberine as natural drug of choice for anti-inflammatory effect to ameliorates OA.

CCN activity and organic hygroscopicity of aerosols downwind of an urban region in central Amazonia: seasonal and diel variations and impact of anthropogenic emissions

Science.gov (United States)

Thalman, Ryan; de Sá, Suzane S.; Palm, Brett B.; Barbosa, Henrique M. J.; Pöhlker, Mira L.; Lizabeth Alexander, M.; Brito, Joel; Carbone, Samara; Castillo, Paulo; Day, Douglas A.; Kuang, Chongai; Manzi, Antonio; Ng, Nga Lee; Sedlacek, Arthur J., III; Souza, Rodrigo; Springston, Stephen; Watson, Thomas; Pöhlker, Christopher; Pöschl, Ulrich; Andreae, Meinrat O.; Artaxo, Paulo; Jimenez, Jose L.; Martin, Scot T.; Wang, Jian

2017-10-01

During the Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5) campaign, size-resolved cloud condensation nuclei (CCN) spectra were characterized at a research site (T3) 60 km downwind of the city of Manaus, Brazil, in central Amazonia for 1 year (12 March 2014 to 3 March 2015). Particle hygroscopicity (κCCN) and mixing state were derived from the size-resolved CCN spectra, and the hygroscopicity of the organic component of the aerosol (κorg) was then calculated from κCCN and concurrent chemical composition measurements. The annual average κCCN increased from 0.13 at 75 nm to 0.17 at 171 nm, and the increase was largely due to an increase in sulfate volume fraction. During both wet and dry seasons, κCCN, κorg, and particle composition under background conditions exhibited essentially no diel variations. The constant κorg of ˜ 0. 15 is consistent with the largely uniform and high O : C value (˜ 0. 8), indicating that the aerosols under background conditions are dominated by the aged regional aerosol particles consisting of highly oxygenated organic compounds. For air masses strongly influenced by urban pollution and/or local biomass burning, lower values of κorg and organic O : C atomic ratio were observed during night, due to accumulation of freshly emitted particles, dominated by primary organic aerosol (POA) with low hygroscopicity, within a shallow nocturnal boundary layer. The O : C, κorg, and κCCN increased from the early morning hours and peaked around noon, driven by the formation and aging of secondary organic aerosol (SOA) and dilution of POA emissions into a deeper boundary layer, while the development of the boundary layer, which leads to mixing with aged particles from the residual layer aloft, likely also contributed to the increases. The hygroscopicities associated with individual organic factors, derived from PMF (positive matrix factorization) analysis of AMS (aerosol mass spectrometry) spectra, were estimated through

Airborne measurement of submicron aerosol number concentration and CCN activity in and around the Korean Peninsula and their comparison to ground measurement in Seoul

Science.gov (United States)

Park, M.; Kim, N.; Yum, S. S.

2016-12-01

Aerosols exert impact not only on human health and visibility but also on climate change directly by scattering or absorbing solar radiation and indirectly by acting as cloud condensation nuclei (CCN) and thus altering cloud radiative and microphysical properties. Aerosol indirect effects on climate has been known to have large uncertainty because of insufficient measurement data on aerosol and CCN activity distribution. Submicron aerosol number concentration (NCN, TSI CPC) and CCN number concentration (NCCN, DMT CCNC) were measured on board the NASA DC-8 research aircraft and at a ground site at Olympic Park in Seoul from May 2nd to June 10th, 2016. CCNC on the airborne platform was operated with the fixed internal supersaturation of 0.6% and CCNC at the ground site was operated with the five different supersaturations (0.2%, 0.4%, 0.6%, 0.8%, and 1.0%). The NASA DC-8 conducted 20 research flights (about 150 hours) in and around the Korean Peninsula and the ground measurement at Olympic Park was continuously made during the measurement period. Both airborne and ground measurements showed spatially and temporally varied aerosol number concentration and CCN activity. Aerosol number concentration in the boundary layer measured on airborne platform was highly affected by pollution sources on the ground. The average diurnal distribution of ground aerosol number concentration showed distinct peaks are located at about 0800, 1500, and 2000. The middle peak indicates that new particle formation events frequently occurred during the measurement period. CCN activation ratio at 0.6% supersaturation (NCCN/NCN) of the airborne measurement ranged from 0.1 to 0.9, indicating that aerosol properties in and around the Korean Peninsula varied so much (e. g. size, hygroscopicity). Comprehensive analysis results will be shown at the conference.

Aerosol optical properties relevant to regional remote sensing of CCN activity and links to their organic mass fraction: airborne observations over Central Mexico and the US West Coast during MILAGRO/INTEX-B

Science.gov (United States)

Shinozuka, Y.; Clarke, A. D.; Decarlo, P. F.; Jimenez, J. L.; Dunlea, E. J.; Roberts, G. C.; Tomlinson, J. M.; Collins, D. R.; Howell, S. G.; Kapustin, V. N.; McNaughton, C. S.; Zhou, J.

2009-09-01

Remote sensing of cloud condensation nuclei (CCN) would help evaluate the indirect effects of tropospheric aerosols on clouds and climate. To assess its feasibility, we examined relationships of submicron aerosol composition to CCN activity and optical properties observed during the MILAGRO/INTEX-B aircraft campaigns. An indicator of CCN activity, κ, was calculated from hygroscopicity measured under saturation. κ for dry 100 nm particles decreased with increasing organic fraction of non-refractory mass of submicron particles (OMF) as 0.34-0.20×OMF over Central Mexico and 0.47-0.43×OMF over the US West Coast. These fits represent the critical dry diameter, centered near 100 nm for 0.2% supersaturation but varied as κ(-1/3), within measurement uncertainty (~20%). The decreasing trends of CCN activity with the organic content, evident also in our direct CCN counts, were consistent with previous ground and laboratory observations of highly organic particles. The wider range of OMF, 0-0.8, for our research areas means that aerosol composition will be more critical for estimation of CCN concentration than at the fixed sites previously studied. Furthermore, the wavelength dependence of extinction was anti-correlated with OMF as -0.70×OMF+2.0 for Central Mexico's urban and industrial pollution air masses, for unclear reasons. The Angstrom exponent of absorption increased with OMF, more rapidly under higher single scattering albedo, as expected for the interplay between soot and colored weak absorbers (some organic species and dust). Because remote sensing products currently use the wavelength dependence of extinction albeit in the column integral form and may potentially include that of absorption, these regional spectral dependencies are expected to facilitate retrievals of aerosol bulk chemical composition and CCN activity over Central Mexico.

Nucleation and condensational growth to CCN sizes during a sustained pristine biogenic SOA event in a forested mountain valley

Directory of Open Access Journals (Sweden)

J. R. Pierce

2012-04-01

Full Text Available The Whistler Aerosol and Cloud Study (WACS 2010, included intensive measurements of trace gases and particles at two sites on Whistler Mountain. Between 6–11 July 2010 there was a sustained high-pressure system over the region with cloud-free conditions and the highest temperatures of the study. During this period, the organic aerosol concentrations rose from <1 μg m⁻³ to ∼6 μg m⁻³. Precursor gas and aerosol composition measurements show that these organics were almost entirely of secondary biogenic nature. Throughout 6–11 July, the anthropogenic influence was minimal with sulfate concentrations <0.2 μg m⁻³ and SO₂ mixing ratios ≈ 0.05–0.1 ppbv. Thus, this case provides excellent conditions to probe the role of biogenic secondary organic aerosol in aerosol microphysics. Although SO₂ mixing ratios were relatively low, box-model simulations show that nucleation and growth may be modeled accurately if J_nuc = 3 × 10⁻⁷[H₂SO₄] and the organics are treated as effectively non-volatile. Due to the low condensation sink and the fast condensation rate of organics, the nucleated particles grew rapidly (2–5 nm h⁻¹ with a 10–25% probability of growing to CCN sizes (100 nm in the first two days as opposed to being scavenged by coagulation with larger particles. The nucleated particles were observed to grow to ∼200 nm after three days. Comparisons of size-distribution with CCN data show that particle hygroscopicity (κ was ∼0.1 for particles larger 150 nm, but for smaller particles near 100 nm the κ value decreased near midway through the period from 0.17 to less than 0.06. In this environment of little anthropogenic influence and low SO₂, the rapid growth rates of the regionally nucleated particles – due to condensation of biogenic SOA – results in an unusually high efficiency of conversion of

CCN activity and organic hygroscopicity of aerosols downwind of an urban region in central Amazonia: seasonal and diel variations and impact of anthropogenic emissions

Directory of Open Access Journals (Sweden)

R. Thalman

2017-10-01

Full Text Available During the Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5 campaign, size-resolved cloud condensation nuclei (CCN spectra were characterized at a research site (T3 60 km downwind of the city of Manaus, Brazil, in central Amazonia for 1 year (12 March 2014 to 3 March 2015. Particle hygroscopicity (κCCN and mixing state were derived from the size-resolved CCN spectra, and the hygroscopicity of the organic component of the aerosol (κorg was then calculated from κCCN and concurrent chemical composition measurements. The annual average κCCN increased from 0.13 at 75 nm to 0.17 at 171 nm, and the increase was largely due to an increase in sulfate volume fraction. During both wet and dry seasons, κCCN, κorg, and particle composition under background conditions exhibited essentially no diel variations. The constant κorg of ∼ 0. 15 is consistent with the largely uniform and high O : C value (∼ 0. 8, indicating that the aerosols under background conditions are dominated by the aged regional aerosol particles consisting of highly oxygenated organic compounds. For air masses strongly influenced by urban pollution and/or local biomass burning, lower values of κorg and organic O : C atomic ratio were observed during night, due to accumulation of freshly emitted particles, dominated by primary organic aerosol (POA with low hygroscopicity, within a shallow nocturnal boundary layer. The O : C, κorg, and κCCN increased from the early morning hours and peaked around noon, driven by the formation and aging of secondary organic aerosol (SOA and dilution of POA emissions into a deeper boundary layer, while the development of the boundary layer, which leads to mixing with aged particles from the residual layer aloft, likely also contributed to the increases. The hygroscopicities associated with individual organic factors, derived from PMF (positive matrix factorization analysis of AMS (aerosol mass

Role of atmospheric aerosol concentration on deep convective precipitation: Cloud-resolving model simulations

Science.gov (United States)

Tao, Wei-Kuo; Li, Xiaowen; Khain, Alexander; Matsui, Toshihisa; Lang, Stephen; Simpson, Joanne

2007-12-01

A two-dimensional cloud-resolving model with detailed spectral bin microphysics is used to examine the effect of aerosols on three different deep convective cloud systems that developed in different geographic locations: south Florida, Oklahoma, and the central Pacific. A pair of model simulations, one with an idealized low cloud condensation nuclei (CCN) (clean) and one with an idealized high CCN (dirty environment), is conducted for each case. In all three cases, rain reaches the ground earlier for the low-CCN case. Rain suppression is also evident in all three cases with high CCN. However, this suppression only occurs during the early stages of the simulations. During the mature stages of the simulations the effects of increasing aerosol concentration range from rain suppression in the Oklahoma case to almost no effect in the Florida case to rain enhancement in the Pacific case. The model results suggest that evaporative cooling in the lower troposphere is a key process in determining whether high CCN reduces or enhances precipitation. Stronger evaporative cooling can produce a stronger cold pool and thus stronger low-level convergence through interactions with the low-level wind shear. Consequently, precipitation processes can be more vigorous. For example, the evaporative cooling is more than two times stronger in the lower troposphere with high CCN for the Pacific case. Sensitivity tests also suggest that ice processes are crucial for suppressing precipitation in the Oklahoma case with high CCN. A comparison and review of other modeling studies are also presented.

Plasma NOV/CCN3 Levels Are Closely Associated with Obesity in Patients with Metabolic Disorders

Science.gov (United States)

Pakradouni, Jihane; Le Goff, Wilfried; Calmel, Claire; Antoine, Bénédicte; Villard, Elise; Frisdal, Eric; Abifadel, Marianne; Tordjman, Joan; Poitou, Christine; Bonnefont-Rousselot, Dominique; Bittar, Randa; Bruckert, Eric; Clément, Karine; Fève, Bruno; Martinerie, Cécile; Guérin, Maryse

2013-01-01

Objective Evidence points to a founder of the multifunctional CCN family, NOV/CCN3, as a circulating molecule involved in cardiac development, vascular homeostasis and inflammation. No data are available on the relationship between plasma NOV/CCN3 levels and cardiovascular risk factors in humans. This study investigated the possible relationship between plasma NOV levels and cardiovascular risk factors in humans. Methods NOV levels were measured in the plasma from 594 adults with a hyperlipidemia history and/or with lipid-lowering therapy and/or a body mass index (BMI) >30 kg/m2. Correlations were measured between NOV plasma levels and various parameters, including BMI, fat mass, and plasma triglycerides, cholesterol, glucose, and C-reactive protein. NOV expression was also evaluated in adipose tissue from obese patients and rodents and in primary cultures of adipocytes and macrophages. Results After full multivariate adjustment, we detected a strong positive correlation between plasma NOV and BMI (r = 0.36 p<0.0001) and fat mass (r = 0.33 p<0.0005). According to quintiles, this relationship appeared to be linear. NOV levels were also positively correlated with C-reactive protein but not with total cholesterol, LDL-C or blood glucose. In patients with drastic weight loss induced by Roux-en-Y bariatric surgery, circulating NOV levels decreased by 28% (p<0.02) and 48% (p<0.0001) after 3 and 6 months, respectively, following surgery. In adipose tissue from obese patients, and in human primary cultures NOV protein was detected in adipocytes and macrophages. In mice fed a high fat diet NOV plasma levels and its expression in adipose tissue were also significantly increased compared to controls fed a standard diet. Conclusion Our results strongly suggest that in obese humans and mice plasma NOV levels positively correlated with NOV expression in adipose tissue, and support a possible contribution of NOV to obesity-related inflammation. PMID:23785511

Photochemical aging of secondary organic aerosols: effects on hygroscopic growth and CCN activation

Science.gov (United States)

Buchholz, A.; Mentel, Th. F.; Tillmann, R.; Schlosser, E.; Mildenberger, K.; Clauss, T.; Henning, S.; Kiselev, A.; Stratmann, F.

2009-04-01

Plant emitted volatile organic carbons (VOCs) are a major precursor of secondary organic aerosols (SOA), an important constituent of atmospheric aerosols. The precursors are oxidized via ozonolysis, photooxidation, or by NO3 and form aerosol particles. Due to further oxidation of the organic matter the composition of the SOA may age with time. This will also change the hygroscopic growth (HG) and cloud condensation nuclei (CCN) activation of the particles. In this study we generated and aged SOA in the SAPHIR chamber at the Research Centre Juelich under near atmospheric conditions: natural sunlight, low precursor and O3 concentrations, and long reaction times. As precursor we used a mixture of 5 monoterpenes (MT) or 5 MT with 2 sesquiterpenes which had been identified as major constituents of plant emissions in previous experiments. Concentrations ranged between 4 and 100 ppb MT and the total reaction time was 36h. HG was measured at RH=10-97% by a Hygroscopic Tandem Differential Analyser (HTDMA, FZ Juelich) and at RH=97-99% by the Leipzig Aerosol Cloud Interaction Simulator (LACIS-mobile, IfT Leipzig). The agreement between HTDMA and LACIS-mobile data was generally good. CCN properties were measured with a continuous flow CCN Counter from DMT. SOA particles generated on a sunny day were more hygroscopic and had a lower activation diameter (Dcrit) than SOA formed under cloudy conditions. With aging it became more hygroscopic and Dcrit decreased. Sunlight enhanced this effect. But the change in HG and Dcrit due to aging was less than the difference between SOA generated under different conditions (i.e. sunny or cloudy). We did not observe a dependence of the HG on the precursor concentration.

Measuring the CCN and IN ability of bacterial isolates: implications for the southeastern United States and Puerto Rico

Science.gov (United States)

Purdue, S.; Waters, S.; Konstantinidis, K.; Nenes, A.; DeLeon-Rodriguez, N.

2015-12-01

Ice nucleation is an important process in the climate system as it influences global precipitation processes, and can affect the vertical distribution of clouds with effects that both cool and warm the atmosphere. Of the pathways to ice nucleation, immersion mode, which occurs when ice nuclei (IN) particles are surrounded by an aqueous phase that subsequently freezes, dominates primary ice production in mixed-phase clouds. A simple but effective method to study immersion freezing is to utilize a droplet freezing assay (DFA) that consists of an aluminum plate, precisely cooled by a continuous flow of an ethylene glycol-water mixture. Using such a system we study the immersion IN characteristics of bacterial isolates (for temperatures ranging from -15oC to 0oC) isolated from rainwater and air collected in Atlanta, GA and Puerto Rico, over storms throughout the year. Despite their relatively large size and the presence of hydrophilic groups on the outer membranes of many bacteria, it is unclear if bacteria possess an inherent ability to nucleate an aqueous phase (a requirement for immersion freezing) for the wide range of supersaturations found in clouds. For this, we measure the cloud condensation nucleation (CCN) activity of each isolate (over the 0.05% to 0.6% supersaturation range) using a Continuous Flow Streamwise Thermal Gradient CCN Counter. Initial results have shown certain isolates to be very efficient CCN, allowing them to form droplets even for the very low supersaturations found in radiation fogs. In combination, these experiments provide insight into the potential dual-ability of some bacteria, isolated from the southeastern United States and Puerto Rico, to act as both efficient CCN and IN.

Using different assumptions of aerosol mixing state and chemical composition to predict CCN concentrations based on field measurements in urban Beijing

Science.gov (United States)

Ren, Jingye; Zhang, Fang; Wang, Yuying; Collins, Don; Fan, Xinxin; Jin, Xiaoai; Xu, Weiqi; Sun, Yele; Cribb, Maureen; Li, Zhanqing

2018-05-01

Understanding the impacts of aerosol chemical composition and mixing state on cloud condensation nuclei (CCN) activity in polluted areas is crucial for accurately predicting CCN number concentrations (NCCN). In this study, we predict NCCN under five assumed schemes of aerosol chemical composition and mixing state based on field measurements in Beijing during the winter of 2016. Our results show that the best closure is achieved with the assumption of size dependent chemical composition for which sulfate, nitrate, secondary organic aerosols, and aged black carbon are internally mixed with each other but externally mixed with primary organic aerosol and fresh black carbon (external-internal size-resolved, abbreviated as EI-SR scheme). The resulting ratios of predicted-to-measured NCCN (RCCN_p/m) were 0.90 - 0.98 under both clean and polluted conditions. Assumption of an internal mixture and bulk chemical composition (INT-BK scheme) shows good closure with RCCN_p/m of 1.0 -1.16 under clean conditions, implying that it is adequate for CCN prediction in continental clean regions. On polluted days, assuming the aerosol is internally mixed and has a chemical composition that is size dependent (INT-SR scheme) achieves better closure than the INT-BK scheme due to the heterogeneity and variation in particle composition at different sizes. The improved closure achieved using the EI-SR and INT-SR assumptions highlight the importance of measuring size-resolved chemical composition for CCN predictions in polluted regions. NCCN is significantly underestimated (with RCCN_p/m of 0.66 - 0.75) when using the schemes of external mixtures with bulk (EXT-BK scheme) or size-resolved composition (EXT-SR scheme), implying that primary particles experience rapid aging and physical mixing processes in urban Beijing. However, our results show that the aerosol mixing state plays a minor role in CCN prediction when the κorg exceeds 0.1.

Hygroscopic growth and CCN activity of HULIS from different environments

DEFF Research Database (Denmark)

Kristensen, Thomas Bjerring; Wex, Heike; Nekat, Bettina

2012-01-01

the hygroscopic growth and CCN activity of water extracts (WE) and HULIS extracted from particulate matter (PM) collected at a polluted urban site (Copenhagen, Denmark), a rural site (Melpitz, Germany) and the remote site Storm Peak Laboratory (Colorado, USA) were investigated. Measurements of inorganic ions......, elemental carbon, organic carbon and water soluble organic carbon (WSOC) within the PM confirmed that the sources of aerosol particles most likely differed for the three samples. The hygroscopic properties of the filtered WE were characterized by hygroscopicity parameters for subsaturated conditions (k...

Cloud condensation nuclei in polluted air and biomass burning smoke near the mega-city Guangzhou, China – Part 1: Size-resolved measurements and implications for the modeling of aerosol particle hygroscopicity and CCN activity

Directory of Open Access Journals (Sweden)

D. Rose

2010-04-01

Full Text Available Atmospheric aerosol particles serving as Cloud Condensation Nuclei (CCN are key elements of the hydrological cycle and climate. We measured and characterized CCN in polluted air and biomass burning smoke during the PRIDE-PRD2006 campaign from 1–30 July 2006 at a rural site ~60 km northwest of the mega-city Guangzhou in southeastern China.

CCN efficiency spectra (activated fraction vs. dry particle diameter; 20–290 nm were recorded at water vapor supersaturations (S in the range of 0.068% to 1.27%. The corresponding effective hygroscopicity parameters describing the influence of particle composition on CCN activity were in the range of κ≈0.1–0.5. The campaign average value of κ=0.3 equals the average value of κ for other continental locations. During a strong local biomass burning event, the average value of κ dropped to 0.2, which can be considered as characteristic for freshly emitted smoke from the burning of agricultural waste. At low S (≤0.27%, the maximum activated fraction remained generally well below one, indicating substantial portions of externally mixed CCN-inactive particles with much lower hygroscopicity – most likely soot particles (up to ~60% at ~250 nm.

The mean CCN number concentrations (N_CCN,S ranged from 1000 cm⁻³ at S=0.068% to 16 000 cm⁻³ at S=1.27%, which is about two orders of magnitude higher than in pristine air. Nevertheless, the ratios between CCN concentration and total aerosol particle concentration (integral CCN efficiencies were similar to the ratios observed in pristine continental air (~6% to ~85% at S=0.068% to 1.27%. Based on the measurement data, we have tested different model approaches for the approximation/prediction of N_CCN,S. Depending on S and on the model approach, the relative deviations between observed and predicted N_CCN,S ranged from a few

Biomass-burning impact on CCN number, hygroscopicity and cloud formation during summertime in the eastern Mediterranean

Directory of Open Access Journals (Sweden)

A. Bougiatioti

2016-06-01

Full Text Available This study investigates the concentration, cloud condensation nuclei (CCN activity and hygroscopic properties of particles influenced by biomass burning in the eastern Mediterranean and their impacts on cloud droplet formation. Air masses sampled were subject to a range of atmospheric processing (several hours up to 3 days. Values of the hygroscopicity parameter, κ, were derived from CCN measurements and a Hygroscopic Tandem Differential Mobility Analyzer (HTDMA. An Aerosol Chemical Speciation Monitor (ACSM was also used to determine the chemical composition and mass concentration of non-refractory components of the submicron aerosol fraction. During fire events, the increased organic content (and lower inorganic fraction of the aerosol decreases the values of κ, for all particle sizes. Particle sizes smaller than 80 nm exhibited considerable chemical dispersion (where hygroscopicity varied up to 100 % for particles of same size; larger particles, however, exhibited considerably less dispersion owing to the effects of condensational growth and cloud processing. ACSM measurements indicate that the bulk composition reflects the hygroscopicity and chemical nature of the largest particles (having a diameter of  ∼  100 nm at dry conditions sampled. Based on positive matrix factorization (PMF analysis of the organic ACSM spectra, CCN concentrations follow a similar trend as the biomass-burning organic aerosol (BBOA component, with the former being enhanced between 65 and 150 % (for supersaturations ranging between 0.2 and 0.7 % with the arrival of the smoke plumes. Using multilinear regression of the PMF factors (BBOA, OOA-BB and OOA and the observed hygroscopicity parameter, the inferred hygroscopicity of the oxygenated organic aerosol components is determined. We find that the transformation of freshly emitted biomass burning (BBOA to more oxidized organic aerosol (OOA-BB can result in a 2-fold increase of the inferred organic

Influence of Giant CCN on warm rain processes in the ECHAM5 GCM

Directory of Open Access Journals (Sweden)

R. Posselt

2008-07-01

Full Text Available Increased Cloud Condensation Nuclei (CCN load due to anthropogenic activity might lead to non-precipitating clouds because the cloud drops become smaller (for a constant liquid water content and, therefore, less efficient in rain formation (aerosol indirect effect. Adding giant CCN (GCCN into such a cloud can initiate precipitation (namely, drizzle and, therefore, might counteract the aerosol indirect effect.

The effect of GCCN on global climate on warm clouds and precipitation within the ECHAM5 General Circulation Model (GCM is investigated. Therefore, the newly introduced prognostic rain scheme (Posselt and Lohmann, 2007 is applied so that GCCN are directly activated into rain drops. The ECHAM5 simulations with incorporated GCCN show that precipitation is affected only locally. On the global scale, the precipitation amount does not change. Cloud properties like total water (liquid + rain water and cloud drop number show a larger sensitivity to GCCN. Depending on the amount of added GCCN, the reduction of total water and cloud drops account for up to 20% compared to the control run without GCCN. Thus, the incorporation of the GCCN accelerate the hydrological cycle so that clouds precipitate faster (but not more and less condensed water is accumulated in the atmosphere.

An estimate of the anthropogenic aerosol indirect effect on the climate is obtained by comparing simulations for present-day and pre-industrial climate. The introduction of the prognostic rain scheme lowered the anthropogenic aerosol indirect effect significantly compared to the standard ECHAM5 with the diagnostic rain scheme. The incorporation of the GCCN changes the model state, especially the cloud properties like TWP and N_l. The precipitation changes only locally but globally the precipitation is unaffected because it has to equal the global mean evaporation rate. Changing the cloud properties leads to a local reduction of the aerosol indirect

Impacts of the mixing state and chemical composition on the cloud condensation nuclei (CCN) activity in Beijing during winter, 2016

Science.gov (United States)

Ren, J.; Zhang, F.

2017-12-01

Abstract.Understanding aerosol chemical composition and mixing state on CCN activity in polluted urban area is crucial to determine NCCN accurately and thus to quantify aerosol indirect effects. Aerosol hrgroscopicity, size-resolved cloud condensation nuclei (CCN) concentration and chemical composition are measured under polluted and background conditions in Beijing based on the Air Pollution and Human Health (APHH) field campaign in winter 2016. The CCN number concentration (NCCN) is predicted by using κ-Köhler theory from the PNSD and five simplified of the mixing state and chemical composition. The assumption of EIS (sulfate, nitrate and SOA internally mixed, and POA and BC externally mixed with size-resolved chemical composition) shows the best closure to predict NCCN with the ratio of predicted to measured NCCN of 0.96-1.12 both in POL and BG conditions. Under BG conditions, IB (internal mixture with bulk chemical composition) scheme achieves the best CCN closure during any periods of a day. In polluted days, EIS and IS (internal mixture with size-resolved chemical composition) scheme may achieve better closure than IB scheme due to the heterogeneity in particles composition across different size. ES (external mixture with size-resolved chemical composition) and EB (external mixture with bulk chemical composition) scheme markedly underestimate the NCCN with the ratio of predicted to measured NCCN of 0.6-0.8. In addition, we note that assumptions of size-resolved composition (IS or ES) show very limited promotes by comparing with the assumptions of bulk composition (IB or EB), furthermore, the prediction becomes worse by using size-resolved assumption in clean days. The predicted NCCN during eve-rush periods shows the most sensitivity to the five different assumptions, with ratios of the predicted and measured NCCN ranging from 0.5 to 1.4, reflecting great impacts from evening traffic and cooking sources. The result from the sensitivity examination of predict

On aerosol hygroscopicity, cloud condensation nuclei (CCN spectra and critical supersaturation measured at two remote islands of Korea between 2006 and 2009

Directory of Open Access Journals (Sweden)

J. H. Kim

2011-12-01

Full Text Available Aerosol size distribution, total concentration (i.e. condensation nuclei (CN concentration, N_CN, cloud condensation nuclei (CCN concentration (N_CCN, hygroscopicity at ~90% relative humidity (RH were measured at a background monitoring site at Gosan, Jeju Island, south of the Korean Peninsula in August 2006, April to May 2007 and August to October 2008. Similar measurements took place in August 2009 at another background site (Baengnyeongdo Comprehensive Monitoring Observatory, BCMO on the island of Baengnyeongdo, off the west coast of the Korean Peninsula. Both islands were found to be influenced by continental sources regardless of season and year. Average values for all of the measured N_CCN at 0.2, 0.6 and 1.0% supersaturations (S, N_CN, and geometric mean diameter (D_g from both islands were in the range of 1043–3051 cm⁻³, 2076–4360 cm⁻³, 2713–4694 cm⁻³, 3890–5117 cm⁻³ and 81–98 nm, respectively. Although the differences in D_g and N_CN were small between Gosan and BCMO, N_CCN at various S was much higher at the latter, which is closer to China.

Most of the aerosols were internally mixed and no notable differences in hygroscopicity were found between the days of strong pollution influence and the non-pollution days for both islands. During the 2008 and 2009 campaigns, critical supersaturation for CCN nucleation (S_c for selected particle sizes was measured. Particles of 100 nm diameters had mean S_c of 0.19 ± 0.02% during 2008 and those of 81 and 110 nm diameters had mean S_c of 0.26 ± 0.07% and 0.17 ± 0.04%, respectively, during 2009. The values of the hygroscopicity parameter (κ, estimated from measured S_c, were mostly higher than the κ values

Inflammatory microenvironment and tumor necrosis factor alpha as modulators of periostin and CCN2 expression in human non-healing skin wounds and dermal fibroblasts.

Science.gov (United States)

Elliott, Christopher G; Forbes, Thomas L; Leask, Andrew; Hamilton, Douglas W

2015-04-01

Non-healing skin wounds remain a significant clinical burden, and in recent years, the regulatory role of matricellular proteins in skin healing has received significant attention. Periostin and CCN2 are both upregulated at day 3 post-wounding in murine skin, where they regulate aspects of the proliferative phase of repair including mesenchymal cell infiltration and myofibroblast differentiation. In this study, we examined 1) the wound phenotype and expression patterns of periostin and CCN2 in non-healing skin wounds in humans and 2) the regulation of their expression in wound fibroblasts by tumor necrosis factor α (TNFα) and transforming growth factor-β1 (TGF-β1). Chronic skin wounds had a pro-inflammatory phenotype, characterized by macrophage infiltration, TNFα immunoreactivity, and neutrophil infiltration. Periostin, but not CCN2, was significantly suppressed in non-healing wound edge tissue at the mRNA and protein level compared with non-involved skin. In vitro, human wound edge fibroblasts populations were still able to proliferate and contract collagen gels. Compared to cells from non-involved skin, periostin and α-SMA mRNA levels increased significantly in the presence of TGF-β1 in wound cells and were significantly decreased by TNFα, but not those of Col1A2 or CCN2. In the presence of both TGF-β1 and TNFα, periostin and α-SMA mRNA levels were significantly reduced compared to TGF-β1 treated wound cells. Effects of TGF-β1 and TNFα on gene expression were also more pronounced in wound edge cells compared to non-involved fibroblasts. We conclude that variations in the expression of periostin and CCN2, are related to an inflammatory microenvironment and the presence of TNFα in human chronic wounds. Copyright © 2015. Published by Elsevier B.V.

Analysis of CCN activity of Remote and Combustion Aerosol over the South East Pacific during autumn 2008 and links to Sc cloud properties

Science.gov (United States)

Freitag, S.; Clarke, A. D.; Howell, S. G.; Twohy, C. H.; Snider, J. R.; Toohey, D. W.; Shank, L.; McNaughton, C. S.; Brekhovskikh, V.; Kapustin, V.

2013-12-01

The earth's most extensive Stratocumulus (Sc) deck, situated off the coast of Northern Chile and Southern Peru, strongly influences the radiation budget and climate over the South East Pacific (SEP) by enhancing solar reflection. This feature makes Sc clouds an important constituent for climate modeling, yet these clouds are poorly represented in models. A large uncertainty in understanding the variability in these low cloud fields arises from our deficit in understanding the role of aerosol. Hence, a major goal of the VOCALS (www.eol.ucar.edu/projects/vocals) campaign in 2008 was to further explore and assess interactions of natural and anthropogenic aerosol with Sc clouds in both the more polluted coastal environment and west of 80W where we encountered nearly pristine boundary layer clouds often exposed to cloud-top entrainment of pollution aerosol from the free troposphere. Extensive airborne measurements of size-resolved aerosol volatility and chemical composition collected aboard the NCAR C-130 were analyzed with an aerosol mass spectrometer (AMS) and a single particle soot photometer (SP2) to calculate aerosol hygroscopicity (κ) and predict cloud condensation nuclei (CCN) concentration for all observed air mass types above and below cloud utilizing estimated Sc cloud supersaturations deduced from cloud-processed aerosol size distribution information. The predicted CCN agree to within 10% to measured CCN. Results from this analysis are presented here and CCN variability observed along VOCALS flight tracks is discussed in conjunction with size-resolved cloud droplet information. This includes assessing the impact of aerosol perturbations on the shape of the cloud droplet size distribution parameterized in models and satellite algorithms such as cloud top effective radius retrievals. We will further discuss cloud droplet residual composition collected using a counterflow virtual impactor (CVI) and analyzed with the AMS and SP2. Size resolved variations in

Resolving both entrainment-mixing and number of activated CCN in deep convective clouds

Directory of Open Access Journals (Sweden)

E. Freud

2011-12-01

Full Text Available The number concentration of activated CCN (N_a is the most fundamental microphysical property of a convective cloud. It determines the rate of droplet growth with cloud depth and conversion into precipitation-sized particles and affects the radiative properties of the clouds. However, measuring N_a is not always possible, even in the cores of the convective clouds, because entrainment of sub-saturated ambient air deeper into the cloud lowers the concentrations by dilution and may cause partial or total droplet evaporation, depending on whether the mixing is homogeneous or extreme inhomogeneous, respectively.

Here we describe a methodology to derive N_a based on the rate of cloud droplet effective radius (R_e growth with cloud depth and with respect to the cloud mixing with the entrained ambient air. We use the slope of the tight linear relationship between the adiabatic liquid water mixing ratio and R_e³ (or R_v³ to derive an upper limit for N_a assuming extreme inhomogeneous mixing. Then we tune N_a down to find the theoretical relative humidity that the entrained ambient air would have for each horizontal cloud penetration, in case of homogeneous mixing. This allows us to evaluate both the entrainment and mixing process in the vertical dimension in addition to getting a better estimation for N_a.

We found that the derived N_a from the entire profile data is highly correlated with the independent CCN measurements from below cloud base. Moreover, it was found that mixing of sub-saturated ambient air into the cloud at scales of ~100 m and above is inclined towards the extreme inhomogeneous limit, i.e. that the time scale of droplet evaporation is significantly smaller than that for turbulent mixing. This means that ambient air that entrains

Deregulated expression of connective tissue growth factor (CTGF/CCN2) is linked to poor outcome in human cancer.

Science.gov (United States)

Wells, Julia E; Howlett, Meegan; Cole, Catherine H; Kees, Ursula R

2015-08-01

Connective tissue growth factor (CTGF/CCN2) has long been associated with human cancers. The role it plays in these neoplasms is diverse and tumour specific. Recurring patterns in clinical outcome, histological desmoplasia and mechanisms of action have been found. When CTGF is overexpressed compared to low-expressing normal tissue or is underexpressed compared to high-expressing normal tissue, the functional outcome favours tumour survival and disease progression. CTGF acts by altering proliferation, drug resistance, angiogenesis, adhesion and migration contributing to metastasis. The pattern of CTGF expression and tumour response helps to clarify the role of this matricellular protein across a multitude of human cancers. © 2014 UICC.

CCN Activity, Variability and Influence on Droplet Formation during the HygrA-Cd Campaign in Athens

Directory of Open Access Journals (Sweden)

Aikaterini Bougiatioti

2017-06-01

Full Text Available Measurements of cloud condensation nuclei (CCN concentrations (cm−3 at five levels of supersaturation between 0.2–1%, together with remote sensing profiling and aerosol size distributions, were performed at an urban background site of Athens during the Hygroscopic Aerosols to Cloud Droplets (HygrA-CD campaign. The site is affected by local emissions and long-range transport, as portrayed by the aerosol size, hygroscopicity and mixing state. Application of a state-of-the-art droplet parameterization is used to link the observed size distribution measurements, bulk composition, and modeled boundary layer dynamics with potential supersaturation, droplet number, and sensitivity of these parameters for clouds forming above the site. The sensitivity is then used to understand the source of potential droplet number variability. We find that the importance of aerosol particle concentration levels associated with the background increases as vertical velocities increase. The updraft velocity variability was found to contribute 58–90% (68.6% on average to the variance of the cloud droplet number, followed by the variance in aerosol number (6–32%, average 23.2%. Therefore, although local sources may strongly modulate CCN concentrations, their impact on droplet number is limited by the atmospheric dynamics expressed by the updraft velocity regime.

Three millimeter molecular line observations in Sagittarius B2. 1: Full synthesis mapping study of HNO, CCS, and HC(13)CCN

Science.gov (United States)

Kuan, Yi-Jehng; Snyder, Lewis E.

1994-01-01

We present the first full synthesis maps of the small molecules HNO, CCS, and HC(13)CCN in Sgr B2. We have observed the 3.8 mm continuum, the HNO J(sub K(sub -1)K(sub 1)) = 1(sub O1)-0(sub OO), the CCS J(sub N) = 7(sub 6)-6(sub 5), and the HC(13)CCN J = 9-8 transitions in the core of the Sgr B2 molecular cloud, using the Berkeley Illinois Maryland Association (BIMA) millimeter array and the NRAO 12 m telescope. We have found that HNO exists in five major gas clumps in the Sgr B2 region, which we have labeled HNO(N), HNO(NW), HNO(E), HNO(M), and HNO(S). Of particular interest is HNO(M), a major molecular gas concentration approximately 15 sec west of Sgr B2(M) in a region of young star formation. HNO is found to be closely associated with the ionized gas and might be depleted around bright H II complexes. In general, the peak intensity of the HNO emission is found to be offset from the peak of the continuum emission. We found evidence for some chemical differentiation among the three species, HNO, CCS, and HC(13)CCN, but the abundance ratios are in fair agreement with theoretical models. Two unidentified lines, U81420 and U81518, were observed, and a previously unknown compact dust source was detected. Our HNO data indicate the presence of a rotating approximately (2.2-4.4) x 10(exp 3)solar mass gas envelope surrounding Sgr B2(N), a possible bipolar gas outflow in HNO(M), and possibly a large (approximately 4.2 x 10(exp 4)solar mass) extended rotating disk associated with HNO(S). In addition, the CCS and HC(13)CCN data approximately outline the extended component of Sgr B2 and clearly show that the southern continuum source Sgr B2(S) is actually a major molecular source as well. Consequently, the kinematics of the Sgr B2 molecular cloud is quite complex, but in moving from the northwest to south, the LSR velocity generally changes from 79 to 46 km/s.

Fell-Muir lecture: connective tissue growth factor (CCN2) – a pernicious and pleiotropic player in the development of kidney fibrosis

Science.gov (United States)

Mason, Roger M

2013-01-01

Connective tissue growth factor (CTGF, CCN2) is a member of the CCN family of matricellular proteins. It interacts with many other proteins, including plasma membrane proteins, modulating cell function. It is expressed at low levels in normal adult kidney cells but is increased in kidney diseases, playing important roles in inflammation and in the development of glomerular and interstitial fibrosis in chronic disease. This review reports the evidence for its expression in human and animal models of chronic kidney disease and summarizes data showing that anti-CTGF therapy can successfully attenuate fibrotic changes in several such models, suggesting that therapies targeting CTGF and events downstream of it in renal cells may be useful for the treatment of human kidney fibrosis. Connective tissue growth factor stimulates the development of fibrosis in the kidney in many ways including activating cells to increase extracellular matrix synthesis, inducing cell cycle arrest and hypertrophy, and prolonging survival of activated cells. The relationship between CTGF and the pro-fibrotic factor TGFβ is examined and mechanisms by which CTGF promotes signalling by the latter are discussed. No specific cellular receptors for CTGF have been discovered but it interacts with and activates several plasma membrane proteins including low-density lipoprotein receptor-related protein (LRP)-1, LRP-6, tropomyosin-related kinase A, integrins and heparan sulphate proteoglycans. Intracellular signalling and downstream events triggered by such interactions are reviewed. Finally, the relationships between CTGF and several anti-fibrotic factors, such as bone morphogenetic factor-4 (BMP4), BMP7, hepatocyte growth factor, CCN3 and Oncostatin M, are discussed. These may determine whether injured tissue heals or progresses to fibrosis. PMID:23110747

Chemical and physical properties of biomass burning aerosols and their CCN activity: A case study in Beijing, China.

Science.gov (United States)

Wu, Zhijun; Zheng, Jing; Wang, Yu; Shang, Dongjie; Du, Zhoufei; Zhang, Yuanhang; Hu, Min

2017-02-01

Biomass burning emits large amounts of both trace gases and particles into the atmosphere. It plays a profound role in regional air quality and climate change. In the present study, an intensive campaign was carried out at an urban site in Beijing, China, in June 2014, which covered the winter wheat harvest season over the North China Plain (NCP). Meanwhile, two evident biomass-burning events were observed. A clear burst in ultrafine particles (below 100nm in diameter, PM 1 ) and subsequent particle growth took place during the events. With the growth of the ultrafine particles, the organic fraction of PM 1 increased significantly. The ratio of oxygen to carbon (O:C), which had an average value of 0.23±0.04, did not show an obvious enhancement, indicating that a significant chemical aging process of the biomass-burning aerosols was not observed during the course of events. This finding might have been due to the fact that the biomass-burning events occurred in the late afternoon and grew during the nighttime, which is associated with a low atmospheric oxidation capacity. On average, organics and black carbon (BC) were dominant in the biomass-burning aerosols, accounting for 60±10% and 18±3% of PM 1 . The high organic and BC fractions led to a significant suppression of particle hygroscopicity. Comparisons among hygroscopicity tandem differential mobility analyzer (HTDMA)-derived, cloud condensation nuclei counter (CCNc)-derived, and aerosol mass spectrometer-based hygroscopicity parameter (κ) values were consistent. The mean κ values of biomass-burning aerosols derived from both HTDMA and CCNc measurements were approximately 0.1, regardless of the particle size, indicating that the biomass-burning aerosols were less active. The burst in particle count during the biomass-burning events resulted in an increased number of cloud condensation nuclei (CCN) at supersaturation (SS)=0.2-0.8%. Copyright © 2016 Elsevier B.V. All rights reserved.

Aerosol Properties and Their Impacts on Surface CCN at the ARM Southern Great Plains Site during the 2011 Midlatitude Continental Convective Clouds Experiment

Institute of Scientific and Technical Information of China (English)

Timothy LOGAN; Xiquan DONG; Baike XI

2018-01-01

Aerosol particles are of particular importance because of their impacts on cloud development and precipitation processes over land and ocean.Aerosol properties as well as meteorological observations from the Department of Energy Atmospheric Radiation Measurement (ARM) platform situated in the Southern Great Plains (SGP) are utilized in this study to illustrate the dependence of continental cloud condensation nuclei (CCN) number concentration (NCCN) on aerosol type and transport pathways.ARM-SGP observations from the 2011 Midlatitude Continental Convective Clouds Experiment field campaign are presented in this study and compared with our previous work during the 2009-10 Clouds,Aerosol,and Precipitation in the Marine Boundary Layer field campaign over the current ARM Eastern North Atlantic site.Northerly winds over the SGP reflect clean,continental conditions with aerosol scattering coefficient (σsp) values less than 20 Mm-1 and NCCN values less than 100 cm-3.However,southerly winds over the SGP are responsible for the observed moderate to high correlation (R)among aerosol loading (σsp > 60 Mm-1) and NCCN,carbonaceous chemical species (biomass burning smoke),and precipitable water vapor.This suggests a common transport mechanism for smoke aerosols and moisture via the Gulf of Mexico,indicating a strong dependence on air mass type.NASA MERRA-2 reanalysis aerosol and chemical data are moderately to highly correlated with surface ARM-SGP data,suggesting that this facility can represent surface aerosol conditions in the SGP,especially during strong aerosol loading events that transport via the Gulf of Mexico.Future long-term investigations will help to understand the seasonal influences of air masses on aerosol,CCN,and cloud properties over land in comparison to over ocean.

Three-dimensional cross-linked carbon network wrapped with ordered polyaniline nanowires for high-performance pseudo-supercapacitors

Science.gov (United States)

Hu, Huan; Liu, Shuwu; Hanif, Muddasir; Chen, Shuiliang; Hou, Haoqing

2014-12-01

The polyaniline (PANI)-based pseudo-supercapacitor has been extensively studied due to its good conductivity, ease of synthesis, low-cost monomer, tunable properties and remarkable specific capacitance. In this work, a three-dimensional cross-linked carbon network (3D-CCN) was used as a contact-resistance-free substrate for PANI-based pseudo-supercapacitors. The ordered PANI nanowires (PaNWs) were grown on the 3D-CCN to form PaNWs/3D-CCN composites by in-situ polymerization. The PaNWs/3D-CCN composites exhibited a specific capacitance (Cs) of 1191.8 F g-1 at a current density of 0.5 A g-1 and a superior rate capability with 66.4% capacitance retention at 100.0 A g-1. The high specific capacitance is attributed to the thin PaNW coating and the spaced PANI nanowire array, which ensure a higher utilization of PANI due to the ease of diffusion of protons through/on the PANI nanowires. In addition, the unique 3D-CCN was used as a high-conductivity platform (or skeleton) with no contact resistance for fast electron transfer and facile charge transport within the composites. Therefore, the binder-free composites can process rapid gains or losses of electrons and ions, even at a high current density. As a result, the specific capacitance and rate capability of our composites are remarkably higher than those of other PANI composites.

Comparison of aerosol effects on simulated spring and summer hailstorm clouds

Science.gov (United States)

Yang, Huiling; Xiao, Hui; Guo, Chunwei; Wen, Guang; Tang, Qi; Sun, Yue

2017-07-01

Numerical simulations are carried out to investigate the effect of cloud condensation nuclei (CCN) concentrations on microphysical processes and precipitation characteristics of hailstorms. Two hailstorm cases are simulated, a spring case and a summer case, in a semiarid region of northern China, with the Regional Atmospheric Modeling System. The results are used to investigate the differences and similarities of the CCN effects between spring and summer hailstorms. The similarities are: (1) The total hydrometeor mixing ratio decreases, while the total ice-phase mixing ratio enhances, with increasing CCN concentration; (2) Enhancement of the CCN concentration results in the production of a greater amount of small-sized hydrometeor particles, but a lessening of large-sized hydrometeor particles; (3) As the CCN concentration increases, the supercooled cloud water and rainwater make a lesser contribution to hail, while the ice-phase hydrometeors take on active roles in the growth of hail; (4) When the CCN concentration increases, the amount of total precipitation lessens, while the role played by liquid-phase rainfall in the amount of total precipitation reduces, relatively, compared to that of ice-phase precipitation. The differences between the two storms include: (1) An increase in the CCN concentration tends to reduce pristine ice mixing ratios in the spring case but enhance them in the summer case; (2) Ice-phase hydrometeor particles contribute more to hail growth in the spring case, while liquid water contributes more in the summer case; (3) An increase in the CCN concentration has different effects on surface hail precipitation in different seasons.

A modelling study of the effects of different CCN on contrail formation

Energy Technology Data Exchange (ETDEWEB)

Gleitsmann, G; Zellner, R [Essen Univ. (Gesamthochschule) (Germany). Inst. fuer Physikalische und Theoretische Chemie

1998-12-31

The formation of cloud condensation nuclei (CCN) in the jet regime of a B747 airliner at cruise has been investigated by modelling calculations using the BOAT model. Both homogeneous condensation of H{sub 2}O/H{sub 2}SO{sub 4}-mixtures and heterogeneous deposition of H{sub 2}O on soot surfaces activated by H{sub 2}SO{sub 4} were taken into account. Whereas the heterogeneous condensation leads to particles with average diameters of about 1.3 {mu}m, the homogeneously condensed H{sub 2}O/H{sub 2}SO{sub 4} particles are much smaller ({<=} 7 nm) and do not contribute to visible contrail formation. Nevertheless, they contribute to the atmospheric background aerosol. Using different SO{sub 2} emission indices, it is concluded that the contrail onset is essentially independent of this quantity and depends mainly on ambient temperature and soot activation kinetics. (author) 15 refs.

A modelling study of the effects of different CCN on contrail formation

Energy Technology Data Exchange (ETDEWEB)

Gleitsmann, G.; Zellner, R. [Essen Univ. (Gesamthochschule) (Germany). Inst. fuer Physikalische und Theoretische Chemie

1997-12-31

The formation of cloud condensation nuclei (CCN) in the jet regime of a B747 airliner at cruise has been investigated by modelling calculations using the BOAT model. Both homogeneous condensation of H{sub 2}O/H{sub 2}SO{sub 4}-mixtures and heterogeneous deposition of H{sub 2}O on soot surfaces activated by H{sub 2}SO{sub 4} were taken into account. Whereas the heterogeneous condensation leads to particles with average diameters of about 1.3 {mu}m, the homogeneously condensed H{sub 2}O/H{sub 2}SO{sub 4} particles are much smaller ({<=} 7 nm) and do not contribute to visible contrail formation. Nevertheless, they contribute to the atmospheric background aerosol. Using different SO{sub 2} emission indices, it is concluded that the contrail onset is essentially independent of this quantity and depends mainly on ambient temperature and soot activation kinetics. (author) 15 refs.

Inhibition of connective tissue growth factor (CTGF/CCN2) expression decreases the survival and myogenic differentiation of human rhabdomyosarcoma cells.

Science.gov (United States)

Croci, Stefania; Landuzzi, Lorena; Astolfi, Annalisa; Nicoletti, Giordano; Rosolen, Angelo; Sartori, Francesca; Follo, Matilde Y; Oliver, Noelynn; De Giovanni, Carla; Nanni, Patrizia; Lollini, Pier-Luigi

2004-03-01

Connective tissue growth factor (CTGF/CCN2), a cysteine-rich protein of the CCN (Cyr61, CTGF, Nov) family of genes, emerged from a microarray screen of genes expressed by human rhabdomyosarcoma cells. Rhabdomyosarcoma is a soft tissue sarcoma of childhood deriving from skeletal muscle cells. In this study, we investigated the role of CTGF in rhabdomyosarcoma. Human rhabdomyosarcoma cells of the embryonal (RD/12, RD/18, CCA) and the alveolar histotype (RMZ-RC2, SJ-RH4, SJ-RH30), rhabdomyosarcoma tumor specimens, and normal skeletal muscle cells expressed CTGF. To determine the function of CTGF, we treated rhabdomyosarcoma cells with a CTGF antisense oligonucleotide or with a CTGF small interfering RNA (siRNA). Both treatments inhibited rhabdomyosarcoma cell growth, suggesting the existence of a new autocrine loop based on CTGF. CTGF antisense oligonucleotide-mediated growth inhibition was specifically due to a significant increase in apoptosis, whereas cell proliferation was unchanged. CTGF antisense oligonucleotide induced a strong decrease in the level of myogenic differentiation of rhabdomyosarcoma cells, whereas the addition of recombinant CTGF significantly increased the proportion of myosin-positive cells. CTGF emerges as a survival and differentiation factor and could be a new therapeutic target in human rhabdomyosarcoma.

Simultaneous coastal measurements of ozone deposition fluxes and iodine-mediated particle emission fluxes with subsequent CCN formation

Directory of Open Access Journals (Sweden)

J. D. Whitehead

2010-01-01

Full Text Available Here we present the first observations of simultaneous ozone deposition fluxes and ultrafine particle emission fluxes over an extensive infra-littoral zone. Fluxes were measured by the eddy covariance technique at the Station Biologique de Roscoff, on the coast of Brittany, north-west France. This site overlooks a very wide (3 km littoral zone controlled by very deep tides (9.6 m exposing extensive macroalgae beds available for significant iodine mediated photochemical production of ultrafine particles. The aspect at the Station Biologique de Roscoff provides an extensive and relatively flat, uniform fetch within which micrometeorological techniques may be utilized to study links between ozone deposition to macroalgae (and sea water and ultrafine particle production.

Ozone deposition to seawater at high tide was significantly slower (v_d[O₃]=0.302±0.095 mm s⁻¹ than low tidal deposition. A statistically significant difference in the deposition velocities to macroalgae at low tide was observed between night time (v_d[O₃]=1.00±0.10 mm s⁻¹ and daytime (v_d[O₃]=2.05±0.16 mm s⁻¹ when ultrafine particle formation results in apparent particle emission. Very high emission fluxes of ultrafine particles were observed during daytime periods at low tides ranging from 50 000 particles cm⁻² s⁻¹ to greater than 200 000 particles cm⁻² s⁻¹ during some of the lowest tides. These emission fluxes exhibited a significant relationship with particle number concentrations comparable with previous observations at another location. Apparent particle growth rates were estimated to be in the range 17–150 nm h⁻¹ for particles in the size range 3–10 nm. Under certain conditions, particle growth may be inferred to continue to greater than 120 nm over tens

Impacto de las condiciones de beneficio sobre los compuestos precursores de aroma en granos de cacao (Theobroma cacao L del clon CCN-51.

Directory of Open Access Journals (Sweden)

Andrea Pallares Pallares

2016-01-01

Full Text Available Abstract The influence of the days of fermentation and drying in the aroma compounds (volatile fraction of cocoa beans CCN-51 was evaluated. The method used was Gas ChromatographyMass Spectrometry, coupled to Head Space Solid Phase Micro Extraction (HS-SPMEGC-GS. A multifactorial experimental design was created, containing 15 experiments per repetition. The fermentation technique was microfermentation in boxes, while drying was achieved by exposing the samples to the sun. A Principal Component Analysis (PCA allowed to explain 68% of the total variability associated with aroma characteristics (volatile compounds. Both, desirable and undesirable compounds were identified throughout the processes of fermentation and drying. The benefit process (fermentation and drying was divided in stages depending on the degree of fermentation. The desirable compounds identified were: 3-methy-1-butanol, 2-phenyl-ethanol, benzaldehyde, phenyl acetaldehyde, ethylhexanoate, ethyl benzoate, ethylphenyl acetate and 2-phenyl ethyl acetate, which are associated with odoriferous notes very nice (chocolate, candy, sweet, nutty, honey, fruity, floral. Finally, a pre-treatment of cocoa beans CCN-51 prior to fermentation was proposed to be incorporated during the benefit of the beans as it seems to enhance the formation of desirable aroma compounds.

MCS precipitation and downburst intensity response to increased aerosol concentrations

Science.gov (United States)

Clavner, M.; Cotton, W. R.; van den Heever, S. C.

2015-12-01

Mesoscale convective systems (MCSs) are important contributors to rainfall in the High Plains of the United States as well as producers of severe weather such as hail, tornados and straight-line wind events known as derechos. Past studies have shown that changes in aerosol concentrations serving as cloud condensation nuclei (CCN) alter the MCS hydrometeor characteristics which in turn modify precipitation yield, downdraft velocity, cold-pool strength, storm propagation and the potential for severe weather to occur. In this study, the sensitivity of MCS precipitation characteristics and convective downburst velocities associated with a derecho to changes in CCN concentrations were examined by simulating a case study using the Regional Atmospheric Modeling System (RAMS). The case study of the 8 May 2009 "Super-Derecho" MCS was chosen since it produced a swath of widespread wind damage in association with an embedded large-scale bow echo, over a broad region from the High Plains of western Kansas to the foothills of the Appalachians. The sensitivity of the storm to changes in CCN concentrations was examined by conducting a set of three simulations which differed in the initial aerosol concentration based on output from the 3D chemical transport model, GEOS-Chem. Results from this study indicate that while increasing CCN concentrations led to an increase in precipitation rates, the changes to the derecho strength were not linear. A moderate increase in aerosol concentration reduced the derecho strength, while the simulation with the highest aerosol concentrations increased the derecho intensity. These changes are attributed to the impact of enhanced CCN concentration on the production of convective downbursts. An analysis of aerosol loading impacts on these MCS features will be presented.

Topically Applied Connective Tissue Growth Factor/CCN2 Improves Diabetic Preclinical Cutaneous Wound Healing: Potential Role for CTGF in Human Diabetic Foot Ulcer Healing

OpenAIRE

Henshaw, F. R.; Boughton, P.; Lo, L.; McLennan, S. V.; Twigg, S. M.

2015-01-01

Aims/Hypothesis. Topical application of CTGF/CCN2 to rodent diabetic and control wounds was examined. In parallel research, correlation of CTGF wound fluid levels with healing rate in human diabetic foot ulcers was undertaken. Methods. Full thickness cutaneous wounds in diabetic and nondiabetic control rats were treated topically with 1??g?rhCTGF or vehicle alone, on 2 consecutive days. Wound healing rate was observed on day 14 and wound sites were examined for breaking strength and granulati...

Efficiency of cloud condensation nuclei formation from ultrafine particles

Directory of Open Access Journals (Sweden)

J. R. Pierce

2007-01-01

Full Text Available Atmospheric cloud condensation nuclei (CCN concentrations are a key uncertainty in the assessment of the effect of anthropogenic aerosol on clouds and climate. The ability of new ultrafine particles to grow to become CCN varies throughout the atmosphere and must be understood in order to understand CCN formation. We have developed the Probability of Ultrafine particle Growth (PUG model to answer questions regarding which growth and sink mechanisms control this growth, how the growth varies between different parts of the atmosphere and how uncertainties with respect to the magnitude and size distribution of ultrafine emissions translates into uncertainty in CCN generation. The inputs to the PUG model are the concentrations of condensable gases, the size distribution of ambient aerosol, particle deposition timescales and physical properties of the particles and condensable gases. It was found in most cases that condensation is the dominant growth mechanism and coagulation with larger particles is the dominant sink mechanism for ultrafine particles. In this work we found that the probability of a new ultrafine particle generating a CCN varies from <0.1% to ~90% in different parts of the atmosphere, though in the boundary layer a large fraction of ultrafine particles have a probability between 1% and 40%. Some regions, such as the tropical free troposphere, are areas with high probabilities; however, variability within regions makes it difficult to predict which regions of the atmosphere are most efficient for generating CCN from ultrafine particles. For a given mass of primary ultrafine aerosol, an uncertainty of a factor of two in the modal diameter can lead to an uncertainty in the number of CCN generated as high as a factor for eight. It was found that no single moment of the primary aerosol size distribution, such as total mass or number, is a robust predictor of the number of CCN ultimately generated. Therefore, a complete description of the

Aerosol Effects on Microphysical Processes, Storm Structure, and Cold Pool Strength in Simulated Supercell Thunderstorms from VORTEX-2 and VORTEX-SE

Science.gov (United States)

Guo, M.; Dawson, D. T., II; Baldwin, M. E.; Mansell, E. R.

2017-12-01

The cloud condensation nuclei (CCN) concentration has been found to strongly affect microphysical, dynamical and thermodynamical processes in supercells and other deep convective storms. Moreover, recent simulation studies have shown aerosols effects differ between higher- and lower-CAPE environments. Owing to the known sensitivity of severe storms to microphysical differences, studying the impact of aerosols supercell storms different environments is of clear societal importance. Tornadic environments in the southwastern U.S. are generally characterized by lower magnitudes CAPE and deeper tropospheric moisture than those in the Great Plains. These two regions were the focus of Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX)-2 and VORTEX-Southeast (SE) field campaigns, respectively. In our study, we simulate several cases from VORTEX-2 and -SE with the Advanced Regional Prediction System (ARPS) Model at 6 different CCN concentrations (100-3000 cm-3). We use NSSL 3-moment microphysics parameterization schemeto explicitly predict precipitation particle size distributions and microphysirocess rates. Overall, storms under the higher-CAPE VORTEX-2 environments are more sensitiveto the change of CCN than those under the lower-CAPE VORTEX-SE environments. Updraft volume decreases as CCN increases for the VORTEX-2 cases, whereas the opposite is true but with a much weaker trend for the VORTEX-SE cases. Moreover, the cold pool strength drops dramatically as CCN surpasses 1000 cm-3n the VORTEX-2 cases but barely changes for the VORTEX-SE cases. Through a microphysics budget analysis, we show the change of the importance of ice processes is key to the differing sensitivities. in the VORTEX-2 cases, deposition to ice nuclei, cloud drop freezing and rain drop freezing in the upper levels (5-11km) contribute more to latent heating since more rain and cloud drops are lifted above the freezing level due to stronger updrafts. For CCN concentration over 1000

The Dominant Snow-forming Process in Warm and Cold Mixed-phase Orographic Clouds: Effects of Cloud Condensation Nuclei and Ice Nuclei

Science.gov (United States)

Fan, J.; Rosenfeld, D.; Leung, L. R.; DeMott, P. J.

2014-12-01

Mineral dust aerosols often observed over California in winter and spring from long-range transport can be efficient ice nuclei (IN) and enhance snow precipitation in mixed-phase orographic clouds. On the other hand, local pollution particles can serve as good CCN and suppress warm rain, but their impacts on cold rain processes are uncertain. The main snow-forming mechanism in warm and cold mixed-phase orographic clouds (refer to as WMOC and CMOC, respectively) could be very different, leading to different precipitation response to CCN and IN. We have conducted 1-km resolution model simulations using the Weather Research and Forecasting (WRF) model coupled with a spectral-bin cloud microphysical model for WMOC and CMOC cases from CalWater2011. We investigated the response of cloud microphysical processes and precipitation to CCN and IN with extremely low to extremely high concentrations using ice nucleation parameterizations that connect with dust and implemented based on observational evidences. We find that riming is the dominant process for producing snow in WMOC while deposition plays a more important role than riming in CMOC. Increasing IN leads to much more snow precipitation mainly due to an increase of deposition in CMOC and increased rimming in WMOC. Increasing CCN decreases precipitation in WMOC by efficiently suppressing warm rain, although snow is increased. In CMOC where cold rain dominates, increasing CCN significantly increases snow, leading to a net increase in precipitation. The sensitivity of supercooled liquid to CCN and IN has also been analyzed. The mechanism for the increased snow by CCN and caveats due to uncertainties in ice nucleation parameterizations will be discussed.

WISP3 (CCN6 Is a Secreted Tumor-Suppressor Protein that Modulates IGF Signaling in Inflammatory Breast Cancer

Directory of Open Access Journals (Sweden)

Celina G. Kleer

2004-03-01

Full Text Available Inflammatory breast cancer (IBC is the most lethal form of locally advanced breast cancer. We have found that WISP3 is lost in 80% of human IBC tumors and that it has growth- and angiogenesis-inhibitory functions in breast cancer in vitro and in vivo. WISP3 is a cysteine-rich, putatively secreted protein that belongs to the CCN family. It contains a signal peptide at the N-terminus and four highly conserved motifs. Here, for the first time, we investigate the function of WISP3 protein in relationship to its structural features. We found that WISP3 is secreted into the conditioned media and into the lumens of normal breast ducts. Once secreted, WISP3 was able to decrease, directly or through induction of other molecule(s, the IGF-1-induced activation of the IGF-IR, and two of its main downstream signaling molecules, IRS1 and ERK-1/2, in SUM149 IBC cells. Furthermore, WISP3 containing conditioned media decreased the growth rate of SUM149 cells. This work sheds light into the mechanism of WISP3 function by demonstrating that it is secreted and that, once in the extracellular media, it induces a series of molecular events that leads to modulation of IGF-IR signaling pathways and cellular growth in IBC cells.

The Role of Aerosols on Precipitation Processes: Cloud Resolving Model Simulations

Science.gov (United States)

Tao, Wei-Kuo; Li, X.; Matsui, T.

2012-01-01

Cloud microphysics is inevitably affected by the smoke particle (CCN, cloud condensation nuclei) size distributions below the clouds. Therefore, size distributions parameterized as spectral bin microphysics are needed to explicitly study the effects of atmospheric aerosol concentration on cloud development, rainfall production, and rainfall rates for convective clouds. Recently, a detailed spectral-bin microphysical scheme was implemented into the Goddard Cumulus Ensemble (GCE) model. The formulation for the explicit spectral bin microphysical processes is based on solving stochastic kinetic equations for the size distribution functions of water droplets (i.e., cloud droplets and raindrops), and several types of ice particles [i.e. pristine ice crystals (columnar and plate-like), snow (dendrites and aggregates), graupel and frozen drops/hail]. Each type is described by a special size distribution function containing many categories (i.e., 33 bins). Atmospheric aerosols are also described using number density size-distribution functions. The model is tested by studying the evolution of deep cloud systems in the west Pacific warm pool region, the sub-tropics (Florida) and midlatitudes using identical thermodynamic conditions but with different concentrations of CCN: a low "clean" concentration and a high "dirty" concentration. Results indicate that the low CCN concentration case produces rainfall at the surface sooner than the high CeN case but has less cloud water mass aloft. Because the spectral-bin model explicitly calculates and allows for the examination of both the mass and number concentration of species in each size category, a detailed analysis of the instantaneous size spectrum can be obtained for these cases. It is shown that since the low (CN case produces fewer droplets, larger sizes develop due to greater condensational and collection growth, leading to a broader size spectrum in comparison to the high CCN case. Sensitivity tests were performed to

Matrix reloaded: CCN, tenascin and SIBLING group of matricellular proteins in orchestrating cancer hallmark capabilities.

Science.gov (United States)

Thakur, Ravi; Mishra, Durga Prasad

2016-12-01

Matricellular proteins (MCPs) are the non-structural extracellular matrix (ECM) proteins with various regulatory functions. MCPs are critical regulators of ECM homeostasis and are often found dysregulated in various malignancies. They interact with various proteins like ECM structural proteins, integrins, growth factor receptors and growth factors to modulate their availability and activity. Cancer-supporting MCPs are known to induce proliferation, migration and invasion of cancer cells. MCPs also support cancer stem (like) cell growth and induce a drug-resistant state. Apart from their direct effects on cancer cells, they play key roles in angiogenesis, immunomodulation, stromal cell infiltration, stromal proliferation and matrix remodeling. High expression of various MCPs belonging to the tenascin, CCN and SIBLING families is often associated with aggressive tumors and poor patient prognosis. Due to their differential expression and distinct functional role, these MCPs are perceived as attractive therapeutic targets in cancer. Studies on preclinical models have indicated that targeting tumor-supportive MCPs could be a potent avenue for developing anti-cancer therapies. The MCP receptors, like integrins and some associated growth factor receptors, are already being targeted using pharmacological inhibitors and neutralizing antibodies. Neutralizing antibodies against CCNs, tenascins and SIBLINGs have shown promising results in preclinical cancer models, suggesting an opportunity to develop anti-MCP therapies to target cancer. Peptides derived from anti-cancer MCPs could also serve as therapeutic entities. In the present review, in continuation with the expanding horizon of MCP functions and disease association, we focus on (i) their unique domain arrangement, (ii) their association with cancer hallmarks and (iii) available and possible therapeutic interventions. Copyright © 2016 Elsevier Inc. All rights reserved.

Idealized simulation of the Colorado hailstorm case: comparison of bulk and detailed microphysics

Science.gov (United States)

Geresdi, I.

One of the purposes of the Fourth Cloud Modeling Workshop was to compare different microphysical treatments. In this paper, the results of a widely used bulk treatment and five versions of a detailed microphysical model are presented. Sensitivity analysis was made to investigate the effect of bulk parametrization, ice initiation technique, CCN concentration and collision efficiency of rimed ice crystal-drop collision. The results show that: (i) The mixing ratios of different species of hydrometeors calculated by bulk and one of the detailed models show some similarity. However, the processes of hail/graupel formation are different in the bulk and the detailed models. (ii) Using different ice initiation in the detailed models' different processes became important in the hail and graupel formation. (iii) In the case of higher CCN concentration, the mixing ratio of liquid water, hail and graupel were more sensitive to the value of collision efficiency of rimed ice crystal-drop collision. (iv) The Bergeron-Findeisen process does not work in the updraft core of a convective cloud. The vapor content was always over water saturation; moreover, the supersaturation gradually increased after the appearance of precipitation ice particles.

Organic condensation: a vital link connecting aerosol formation to cloud condensation nuclei (CCN) concentrations

Science.gov (United States)

Riipinen, I.; Pierce, J. R.; Yli-Juuti, T.; Nieminen, T.; Häkkinen, S.; Ehn, M.; Junninen, H.; Lehtipalo, K.; Petäjä, T.; Slowik, J.; Chang, R.; Shantz, N. C.; Abbatt, J.; Leaitch, W. R.; Kerminen, V.-M.; Worsnop, D. R.; Pandis, S. N.; Donahue, N. M.; Kulmala, M.

2011-04-01

Atmospheric aerosol particles influence global climate as well as impair air quality through their effects on atmospheric visibility and human health. Ultrafine (<100 nm) particles often dominate aerosol numbers, and nucleation of atmospheric vapors is an important source of these particles. To have climatic relevance, however, the freshly nucleated particles need to grow in size. We combine observations from two continental sites (Egbert, Canada and Hyytiälä, Finland) to show that condensation of organic vapors is a crucial factor governing the lifetimes and climatic importance of the smallest atmospheric particles. We model the observed ultrafine aerosol growth with a simplified scheme approximating the condensing species as a mixture of effectively non-volatile and semi-volatile species, demonstrate that state-of-the-art organic gas-particle partitioning models fail to reproduce the observations, and propose a modeling approach that is consistent with the measurements. We find that roughly half of the mass of the condensing mass needs to be distributed proportional to the aerosol surface area (thus implying that the condensation is governed by gas-phase concentration rather than the equilibrium vapour pressure) to explain the observed aerosol growth. We demonstrate the large sensitivity of predicted number concentrations of cloud condensation nuclei (CCN) to these interactions between organic vapors and the smallest atmospheric nanoparticles - highlighting the need for representing this process in global climate models.

Modulation of the TGFβ/Smad signaling pathway in mesangial cells by CTGF/CCN2

International Nuclear Information System (INIS)

Abdel Wahab, Nadia; Weston, Benjamin S.; Mason, Roger M.

2005-01-01

Transforming growth factor-beta (TGFβ) drives fibrosis in diseases such as diabetic nephropathy (DN). Connective tissue growth factor (CTGF; CCN2) has also been implicated in this, but the molecular mechanism is unknown. We show that CTGF enhances the TGFβ/Smad signaling pathway by transcriptional suppression of Smad 7 following rapid and sustained induction of the transcription factor TIEG-1. Smad 7 is a known antagonist of TGFβ signaling and TIEG-1 is a known repressor of Smad 7 transcription. CTGF enhanced TGFβ-induced phosphorylation and nuclear translocation of Smad 2 and Smad 3 in mesangial cells. Antisense oligonucleotides directed against TIEG-1 prevented CTGF-induced downregulation of Smad 7. CTGF enhanced TGFβ-stimulated transcription of the SBE4-Luc reporter gene and this was markedly reduced by TIEG-1 antisense oligonucleotides. Expression of the TGFβ-responsive genes PAI-1 and Col III over 48 h was maximally stimulated by TGFβ + CTGF compared to TGFβ alone, while CTGF alone had no significant effect. TGFβ-stimulated expression of these genes was markedly reduced by both CTGF and TIEG-1 antisense oligonucleotides, consistent with the endogenous induction of CTGF by TGFβ. We propose that under pathological conditions, where CTGF expression is elevated, CTGF blocks the negative feedback loop provided by Smad 7, allowing continued activation of the TGFβ signaling pathway

Investigation of the effective peak supersaturation for liquid-phase clouds at the high-alpine site Jungfraujoch, Switzerland (3580 m a.s.l.

Directory of Open Access Journals (Sweden)

E. Hammer

2014-01-01

Full Text Available Aerosols influence the Earth's radiation budget directly through absorption and scattering of solar radiation in the atmosphere but also indirectly by modifying the properties of clouds. However, climate models still suffer from large uncertainties as a result of insufficient understanding of aerosol-cloud interactions. At the high altitude research station Jungfraujoch (JFJ; 3580 m a.s.l., Switzerland cloud condensation nuclei (CCN number concentrations at eight different supersaturations (SS from 0.24% to 1.18% were measured using a CCN counter during Summer 2011. Simultaneously, in-situ aerosol activation properties of the prevailing ambient clouds were investigated by measuring the total and interstitial (non-activated dry particle number size distributions behind two different inlet systems. Combining all experimental data, a new method was developed to retrieve the so-called effective peak supersaturation SSpeak, as a measure of the SS at which ambient clouds are formed. A 17-month CCN climatology was then used to retrieve the SSpeak values also for four earlier summer campaigns (2000, 2002, 2004 and 2010 where no direct CCN data were available. The SSpeak values varied between 0.01% and 2.0% during all campaigns. An overall median SSpeak of 0.35% and dry activation diameter of 87 nm was observed. It was found that the difference in topography between northwest and southeast plays an important role for the effective peak supersaturation in clouds formed in the vicinity of the JFJ, while differences in the number concentration of potential CCN only play a minor role. Results show that air masses coming from the southeast (with the slowly rising terrain of the Aletsch Glacier generally experience lower SSpeak values than air masses coming from the northwest (steep slope. The observed overall median values were 0.41% and 0.22% for northwest and southeast wind conditions, respectively, corresponding to literature values for cumulus clouds and

Global variability of cloud condensation nuclei concentrations

Science.gov (United States)

Makkonen, Risto; Krüger, Olaf

2017-04-01

Atmospheric aerosols can influence cloud optical and dynamical processes by acting as cloud condensation nuclei (CCN). Globally, these indirect aerosol effects are significant to the radiative budget as well as a source of high uncertainty in anthropogenic radiative forcing. While historically many global climate models have fixed CCN concentrations to a certain level, most state-of-the-art models calculate aerosol-cloud interactions with sophisticated methodologies based on interactively simulated aerosol size distributions. However, due to scarcity of atmospheric observations simulated global CCN concentrations remain poorly constrained. Here we assess global CCN variability with a climate model, and attribute potential trends during 2000-2010 to changes in emissions and meteorological fields. Here we have used ECHAM5.5-HAM2 with model M7 microphysical aerosol model. The model has been upgraded with a secondary organic aerosol (SOA) scheme including ELVOCs. Dust and sea salt emissions are calculated online, based on wind speed and hydrology. Each experiment is 11 years, analysed after a 6-month spin-up period. The MODIS CCN product (Terra platform) is used to evaluate model performance throughout 2000-2010. While optical remote observation of CCN column includes several deficiencies, the products serves as a proxy for changes during the simulation period. In our analysis we utilize the observed and simulated vertical column integrated CCN concentration, and limit our analysis only over marine regions. Simulated annual CCN column densities reach 2ṡ108 cm-2 near strong source regions in central Africa, Arabian Sea, Bay of Bengal and China sea. The spatial concentration gradient in CCN(0.2%) is steep, and column densities drop to coasts. While the spatial distribution of CCN at 0.2% supersaturation is closer to that of MODIS proxy, as opposed to 1.0% supersaturation, the overall column integrated CCN are too low. Still, we can compare the relative response of CCN

Adsorption behavior of carboxylated cellulose nanocrystal—polyethyleneimine composite for removal of Cr(VI) ions

Energy Technology Data Exchange (ETDEWEB)

Liu, Chao; Jin, Ru-Na; Ouyang, Xiao-kun, E-mail: xkouyang@zjou.edu.cn; Wang, Yang-Guang

2017-06-30

Highlights: • A carboxylated cellulose nanocrystal-polyethyleneimine composite (CCN-PEI) was prepared. • The as-prepared CCN-PEI was characterized by SEM, TEM, FT-IR, and XPS. • Results suggested that the reusable CCN-PEI could remove Cr(VI) from aqueous solutions with a high adsorption capacity. • The adsorption isotherm, thermodynamics, and kinetics of the adsorption process are also discussed. - Abstract: In this study, a composite adsorbent (CCN-PEI) composed of carboxylated cellulose nanocrystals (CCN) and polyethyleneimine (PEI) was prepared through an amidation reaction between the carboxyl groups of the CCN and the amine groups of the PEI. The adsorption performance of the CCN-PEI was tested by removing Cr(VI) ions from aqueous solutions. The physicochemical properties of the CCN and the Cr(VI) ion-loaded CCN-PEI were studied using scanning electron microscopy (SEM), transmission electron microscopy, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy. To investigate the adsorption kinetics of Cr(VI) ions onto this newly developed CCN-PEI, we performed experiments under different adsorption conditions, by varying the contact time, solution pH, initial Cr(VI) ion concentration, and adsorption temperature. The prepared CCN-PEI exhibited an encouraging uptake capacity of 358.42 mg × g{sup −1}. The adsorption process was fast: within the first 100 min, Cr(VI) ion adsorption onto the CCN-PEI was about 65%, and the adsorption equilibrium was reached within 250 min. Kinetics experiments indicated that the adsorption process could be described by a pseudo-second-order kinetic model. Furthermore, our adsorption equilibrium data fit the Langmuir isotherms well. The calculated thermodynamic parameters, such as the free energy change (ΔG = −2.93 kJ × mol{sup −1}), enthalpy change (ΔH = −5.69 kJ × mol{sup −1}), and entropy change (ΔS = −9.14 kJ × mol{sup −1}), indicate that the adsorption of Cr(VI) ions onto CCN

New Particle Formation in the Mid-Latitude Upper Troposphere

Science.gov (United States)

Axisa, Duncan

Primary aerosol production due to new particle formation (NPF) in the upper troposphere and the impact that this might have on cloud condensation nuclei (CCN) concentration can be of sufficient magnitude to contribute to the uncertainty in radiative forcing. This uncertainty affects our ability to estimate how sensitive the climate is to greenhouse gas emissions. Therefore, new particle formation must be accurately defined, parametrized and accounted for in models. This research involved the deployment of instruments, data analysis and interpretation of particle formation events during the Mid-latitude Airborne Cirrus Properties Experiment (MACPEX) campaign. The approach combined field measurements and observations with extensive data analysis and modeling to study the process of new particle formation and growth to CCN active sizes. Simultaneous measurements of O3, CO, ultrafine aerosol particles and surface area from a high-altitude research aircraft were used to study tropospheric-stratospheric mixing as well as the frequency and location of NPF. It was found that the upper troposphere was an active region in the production of new particles by gas-to-particle conversion, that nucleation was triggered by convective clouds and mixing processes, and that NPF occurred in regions with high relative humidity and low surface area. In certain cases, mesoscale and synoptic features enhanced mixing and facilitated the formation of new particles in the northern mid-latitudes. A modeling study of particle growth and CCN formation was done based on measured aerosol size distributions and modeled growth. The results indicate that when SO2 is of sufficient concentration NPF is a significant source of potential CCN in the upper troposphere. In conditions where convective cloud outflow eject high concentrations of SO2, a large number of new particles can form especially in the instance when the preexisting surface area is low. The fast growth of nucleated clusters produces a

Development and impact of hooks of high droplet concentration on remote southeast Pacific stratocumulus

Directory of Open Access Journals (Sweden)

R. C. George

2013-07-01

Full Text Available Over the southeastern Pacific (SEP, droplet concentration (Nd in the typically unpolluted marine stratocumulus west of 80° W (> 1000 km offshore is periodically strongly enhanced in zonally elongated "hook"-shaped features that increase albedo. Here, we examine three hook events using the chemistry version of the Weather Research and Forecasting model (WRF-Chem with 14 km horizontal resolution, satellite data, and aircraft data from the VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx. A particularly strong hook yields insights into the development, decay, and radiative impact of these features. Hook development occurs with Nd increasing to polluted levels over the remote ocean primarily due to entrainment of cloud condensation nuclei (CCN from the lower free troposphere (FT. The feature advects northwestward until the FT CCN source is depleted, after which Nd decreases over a few days due to precipitation and dilution. The model suggests that the FT CCN source supplying the hook consists of high concentrations of small accumulation-mode aerosols that contribute a relatively small amount of aerosol mass to the MBL, in agreement with near-coast VOCALS measurements of polluted layers in the FT. The aerosol particles in this hook originate mainly from a pulse of offshore flow that transports Santiago-region (33–35° S emissions to the remote marine FT. To provide pollution CCN that can sustain hooks, the FT transport of pollution plumes to the remote ocean requires strong, deep offshore flow. Such flow is favored by a trough approaching the South American coast and a southeastward shift of the climatological subtropical high-pressure system. The model simulations show precipitation suppression in the hook and a corresponding increase in liquid water path (LWP compared with a simulation without anthropogenic sources. LWP also increases as the hook evolves over time due to increasing stability and decreasing subsidence. WRF

Measurements of aerosol and CCN properties in the Mackenzie River delta (Canadian Arctic during spring–summer transition in May 2014

Directory of Open Access Journals (Sweden)

P. Herenz

2018-04-01

Full Text Available Within the framework of the RACEPAC (Radiation–Aerosol–Cloud Experiment in the Arctic Circle project, the Arctic aerosol, arriving at a ground-based station in Tuktoyaktuk (Mackenzie River delta area, Canada, was characterized during a period of 3 weeks in May 2014. Basic meteorological parameters and particle number size distributions (PNSDs were observed and two distinct types of air masses were found. One type were typical Arctic haze air masses, termed accumulation-type air masses, characterized by a monomodal PNSD with a pronounced accumulation mode at sizes above 100 nm. These air masses were observed during a period when back trajectories indicate an air mass origin in the north-east of Canada. The other air mass type is characterized by a bimodal PNSD with a clear minimum around 90 nm and with an Aitken mode consisting of freshly formed aerosol particles. Back trajectories indicate that these air masses, termed Aitken-type air masses, originated from the North Pacific. In addition, the application of the PSCF receptor model shows that air masses with their origin in active fire areas in central Canada and Siberia, in areas of industrial anthropogenic pollution (Norilsk and Prudhoe Bay Oil Field and the north-west Pacific have enhanced total particle number concentrations (NCN. Generally, NCN ranged from 20 to 500 cm−3, while cloud condensation nuclei (CCN number concentrations were found to cover a range from less than 10 up to 250 cm−3 for a supersaturation (SS between 0.1 and 0.7 %. The hygroscopicity parameter κ of the CCN was determined to be 0.23 on average and variations in κ were largely attributed to measurement uncertainties. Furthermore, simultaneous PNSD measurements at the ground station and on the Polar 6 research aircraft were performed. We found a good agreement of ground-based PNSDs with those measured between 200 and 1200 m. During two of the four overflights, particle number concentrations at 3000

Cloud condensation nuclei droplet growth kinetics of ultrafine particles during anthropogenic nucleation events

Science.gov (United States)

Shantz, N. C.; Pierce, J. R.; Chang, R. Y.-W.; Vlasenko, A.; Riipinen, I.; Sjostedt, S.; Slowik, J. G.; Wiebe, A.; Liggio, J.; Abbatt, J. P. D.; Leaitch, W. R.

2012-02-01

Evolution of the cloud condensation nucleus (CCN) activity of 36 ± 4 nm diameter anthropogenic aerosol particles at a water supersaturation of 1.0 ± 0.1% is examined for particle nucleation and growth. During the early stages of one event, relatively few of the anthropogenic particles at 36 nm were CCN active and their growth rates by water condensation were delayed relative to ammonium sulphate particles. As the event progressed, the particle size distribution evolved to larger sizes and the relative numbers of particles at 36 nm that were CCN active increased until all the 36 nm particles were activating at the end of the event. Based on the chemistry of larger particles and the results from an aerosol chemical microphysics box model, the increase in CCN activity of the particles was most likely the result of the condensation of sulphate in this case. Despite the increased CCN activity, a delay was observed in the initial growth of these particles into cloud droplets, which persisted even when the aerosol was most CCN active later in the afternoon. Simulations show that the delay in water uptake is explained by a reduction of the mass accommodation coefficient assuming that the composition of the 36 nm particles is the same as the measured composition of the 60-100 nm particles.

Final Report, The Influence of Organic-Aerosol Emissions and Aging on Regional and Global Aerosol Size Distributions and the CCN Number Budget

Energy Technology Data Exchange (ETDEWEB)

Donahue, Neil M. [Carnegie Mellon Univ., Pittsburgh, PA (United States)

2015-12-23

We conducted laboratory experiments and analyzed data on aging of organic aerosol and analysis of field data on volatility and CCN activity. With supplemental ASR funding we participated in the FLAME-IV campaign in Missoula MT in the Fall of 2012, deploying a two-chamber photochemical aging system to enable experimental exploration of photochemical aging of biomass burning emissions. Results from that campaign will lead to numerous publications, including demonstration of photochemical production of Brown Carbon (BrC) from secondary organic aerosol associated with biomass burning emissions as well as extensive characterization of the effect of photochemical aging on the overall concentrations of biomass burning organic aerosol. Excluding publications arising from the FLAME-IV campaign, project research resulted in 8 papers: [11, 5, 3, 10, 12, 4, 8, 7], including on in Nature Geoscience addressing the role of organic compounds in nanoparticle growth [11

CCN concentrations and BC warming influenced by maritime ship emitted aerosol plumes over southern Bay of Bengal.

Science.gov (United States)

Ramana, M V; Devi, Archana

2016-08-02

Significant quantities of carbon soot aerosols are emitted into pristine parts of the atmosphere by marine shipping. Soot impacts the radiative balance of the Earth-atmosphere system by absorbing solar-terrestrial radiation and modifies the microphysical properties of clouds. Here we examined the impact of black carbon (BC) on net warming during monsoon season over southern Bay-of-Bengal, using surface and satellite measurements of aerosol plumes from shipping. Shipping plumes had enhanced the BC concentrations by a factor of four around the shipping lane and exerted a strong positive influence on net warming. Compiling all the data, we show that BC atmospheric heating rates for relatively-clean and polluted-shipping corridor locations to be 0.06 and 0.16 K/day respectively within the surface layer. Emissions from maritime ships had directly heated the lower troposphere by two-and-half times and created a gradient of around 0.1 K/day on either side of the shipping corridor. Furthermore, we show that ship emitted aerosol plumes were responsible for increase in the concentration of cloud condensation nuclei (CCN) by an order of magnitude that of clean air. The effects seen here may have significant impact on the monsoonal activity over Bay-of-Bengal and implications for climate change mitigation strategies.

Class 2 piping rules in elevated temperature applications compared with Class 1 prescriptions for LMFBRs

International Nuclear Information System (INIS)

Capello, R.; Stretti, G.; Cesari, F.G.

1989-01-01

An LMFBR plant has many piping systems subjected to elevated temperature (> 427 o C) which, depending on their function and safety criteria, are classified as of quality level 1 or 2. The design of class 1 and class 2 piping for elevated temperatures is performed in accordance with ASME CCN-47 and CCN-253 respectively. This paper discusses what level of knowledge and analysis is necessary, to apply the rules of class 2 (CCN-253) rather than those of class 1 (CCN-47) for the design analysis of piping systems. From the designer viewpoint the burden of verification is much greater in class 1 than in class 2. This paper also examines the reliability of class 2 rules for elevated temperature when used to obtain structural results and justify the design of class 1 systems. In fact it can be shown that in some cases it is possible to design class 1 piping systems using class 2 rules. (author)

Evaluation of Community Care Network (CCN) system in a rural health care setting.

Science.gov (United States)

Galfalvy, H C; Reddy, S M; Niewiadomska-Bugaj, M; Friedman, S; Merkin, B

1995-01-01

Concurrent Engineering Research Center (CERC), under the sponsorship of NLM (National Library of Medicine) is in the process of developing a computerized patient record system for a clinical environment distributed in rural West Virginia. This realization of the CCN (Community Care Network), besides providing computer-based patient records accessible from a chain of clinics and one hospital, supports collaborative health care processes like referral and consulting. To evaluate the effectiveness of the system, a study was designed and is in the process of being executed. Three surveys were designed to provide subjective measures, and four experiments for collecting objective data. Data collection is taking place in several phases: baseline data are collected before the system is deployed; the process is repeated with minimal changes three, then six months later or as often as new versions of the system are installed. Results are then to be compared, using whenever possible matching techniques (i.e. the preliminary data collected on a provider will be matched with the data collected later on the same provider). Surveys are conducted through questionnaires distributed to providers and nurses and person-to-person interviews of the patients. The time spent on patient-chart related activities is measured by work-sampling, aided by a computer application running on a laptop PC. Information about missing patient record parts is collected by the providers, the frequency by which new features of the computerized system are used will be logged by the system itself and clinical outcome measures will be studied from the results of the clinics' own patient chart audits. Preliminary results of the surveys and plans for the immediate and distant future are discussed at the end of the paper.

Long-term cloud condensation nuclei number concentration, particle number size distribution and chemical composition measurements at regionally representative observatories

Science.gov (United States)

Schmale, Julia; Henning, Silvia; Decesari, Stefano; Henzing, Bas; Keskinen, Helmi; Sellegri, Karine; Ovadnevaite, Jurgita; Pöhlker, Mira L.; Brito, Joel; Bougiatioti, Aikaterini; Kristensson, Adam; Kalivitis, Nikos; Stavroulas, Iasonas; Carbone, Samara; Jefferson, Anne; Park, Minsu; Schlag, Patrick; Iwamoto, Yoko; Aalto, Pasi; Äijälä, Mikko; Bukowiecki, Nicolas; Ehn, Mikael; Frank, Göran; Fröhlich, Roman; Frumau, Arnoud; Herrmann, Erik; Herrmann, Hartmut; Holzinger, Rupert; Kos, Gerard; Kulmala, Markku; Mihalopoulos, Nikolaos; Nenes, Athanasios; O'Dowd, Colin; Petäjä, Tuukka; Picard, David; Pöhlker, Christopher; Pöschl, Ulrich; Poulain, Laurent; Prévôt, André Stephan Henry; Swietlicki, Erik; Andreae, Meinrat O.; Artaxo, Paulo; Wiedensohler, Alfred; Ogren, John; Matsuki, Atsushi; Yum, Seong Soo; Stratmann, Frank; Baltensperger, Urs; Gysel, Martin

2018-02-01

Aerosol-cloud interactions (ACI) constitute the single largest uncertainty in anthropogenic radiative forcing. To reduce the uncertainties and gain more confidence in the simulation of ACI, models need to be evaluated against observations, in particular against measurements of cloud condensation nuclei (CCN). Here we present a data set - ready to be used for model validation - of long-term observations of CCN number concentrations, particle number size distributions and chemical composition from 12 sites on 3 continents. Studied environments include coastal background, rural background, alpine sites, remote forests and an urban surrounding. Expectedly, CCN characteristics are highly variable across site categories. However, they also vary within them, most strongly in the coastal background group, where CCN number concentrations can vary by up to a factor of 30 within one season. In terms of particle activation behaviour, most continental stations exhibit very similar activation ratios (relative to particles > 20 nm) across the range of 0.1 to 1.0 % supersaturation. At the coastal sites the transition from particles being CCN inactive to becoming CCN active occurs over a wider range of the supersaturation spectrum. Several stations show strong seasonal cycles of CCN number concentrations and particle number size distributions, e.g. at Barrow (Arctic haze in spring), at the alpine stations (stronger influence of polluted boundary layer air masses in summer), the rain forest (wet and dry season) or Finokalia (wildfire influence in autumn). The rural background and urban sites exhibit relatively little variability throughout the year, while short-term variability can be high especially at the urban site. The average hygroscopicity parameter, κ, calculated from the chemical composition of submicron particles was highest at the coastal site of Mace Head (0.6) and lowest at the rain forest station ATTO (0.2-0.3). We performed closure studies based on κ-Köhler theory

Laboratory studies of the chemical composition and cloud condensation nuclei (CCN activity of secondary organic aerosol (SOA and oxidized primary organic aerosol (OPOA

Directory of Open Access Journals (Sweden)

A. T. Lambe

2011-09-01

Full Text Available Secondary organic aerosol (SOA and oxidized primary organic aerosol (OPOA were produced in laboratory experiments from the oxidation of fourteen precursors representing atmospherically relevant biogenic and anthropogenic sources. The SOA and OPOA particles were generated via controlled exposure of precursors to OH radicals and/or O₃ in a Potential Aerosol Mass (PAM flow reactor over timescales equivalent to 1–20 days of atmospheric aging. Aerosol mass spectra of SOA and OPOA were measured with an Aerodyne aerosol mass spectrometer (AMS. The fraction of AMS signal at m/z = 43 and m/z = 44 (f₄₃, f₄₄, the hydrogen-to-carbon (H/C ratio, and the oxygen-to-carbon (O/C ratio of the SOA and OPOA were obtained, which are commonly used to characterize the level of oxidation of oxygenated organic aerosol (OOA. The results show that PAM-generated SOA and OPOA can reproduce and extend the observed f₄₄–f₄₃ composition beyond that of ambient OOA as measured by an AMS. Van Krevelen diagrams showing H/C ratio as a function of O/C ratio suggest an oxidation mechanism involving formation of carboxylic acids concurrent with fragmentation of carbon-carbon bonds. Cloud condensation nuclei (CCN activity of PAM-generated SOA and OPOA was measured as a function of OH exposure and characterized as a function of O/C ratio. CCN activity of the SOA and OPOA, which was characterized in the form of the hygroscopicity parameter κ_org, ranged from 8.4×10⁻⁴ to 0.28 over measured O/C ratios ranging from 0.05 to 1.42. This range of κ_org and O/C ratio is significantly wider than has been previously obtained. To first order, the κ_org-to-O/C relationship is well represented by a linear function of the form κ_org = (0.18±0.04 ×O/C + 0.03, suggesting that a simple, semi-empirical parameterization of OOA hygroscopicity and

Targeting CCl4 -induced liver fibrosis by RNA interference-mediated inhibition of cyclin E1 in mice.

Science.gov (United States)

Bangen, Jörg-Martin; Hammerich, Linda; Sonntag, Roland; Baues, Maike; Haas, Ute; Lambertz, Daniela; Longerich, Thomas; Lammers, Twan; Tacke, Frank; Trautwein, Christian; Liedtke, Christian

2017-10-01

Initiation and progression of liver fibrosis requires proliferation and activation of resting hepatic stellate cells (HSCs). Cyclin E1 (CcnE1) is the regulatory subunit of the cyclin-dependent kinase 2 (Cdk2) and controls cell cycle re-entry. We have recently shown that genetic inactivation of CcnE1 prevents activation, proliferation, and survival of HSCs and protects from liver fibrogenesis. The aim of the present study was to translate these findings into preclinical applications using an RNA interference (RNAi)-based approach. CcnE1-siRNA (small interfering RNA) efficiently inhibited CcnE1 gene expression in murine and human HSC cell lines and in primary HSCs, resulting in diminished proliferation and increased cell death. In C57BL/6 wild-type (WT) mice, delivery of stabilized siRNA using a liposome-based carrier targeted approximately 95% of HSCs, 70% of hepatocytes, and 40% of CD45 + cells after single injection. Acute CCl 4 -mediated liver injury in WT mice induced endogenous CcnE1 expression and proliferation of surviving hepatocytes and nonparenchymal cells, including CD45 + leukocytes. Pretreatment with CcnE1-siRNA reverted CcnE1 induction to baseline levels of healthy mice, which was associated with reduced liver injury, diminished proliferation of hepatocytes and leukocytes, and attenuated overall inflammatory response. For induction of liver fibrosis, WT mice were challenged with CCl 4 for 4-6 weeks. Co-treatment with CcnE1-siRNA once a week was sufficient to continuously block CcnE1 expression and cell-cycle activity of hepatocytes and nonparenchymal cells, resulting in significantly ameliorated liver fibrosis and inflammation. Importantly, CcnE1-siRNA also prevented progression of liver fibrosis if applied after onset of chronic liver injury. Therapeutic targeting of CcnE1 in vivo using RNAi is feasible and has high antifibrotic activity. (Hepatology 2017;66:1242-1257). © 2017 by the American Association for the Study of Liver Diseases.

Updating of ASME Nuclear Code Case N-201 to Accommodate the Needs of Metallic Core Support Structures for High Temperature Gas Cooled Reactors Currently in Development

International Nuclear Information System (INIS)

Basol, Mit; Kielb, John F.; MuHooly, John F.; Smit, Kobus

2007-01-01

On September 29, 2005, ASME Standards Technology, LLC (ASME ST-LLC) executed a multi-year, cooperative agreement with the United States DOE for the Generation IV Reactor Materials project. The project's objective is to update and expand appropriate materials, construction, and design codes for application in future Generation IV nuclear reactor systems that operate at elevated temperatures. Task 4 was embarked upon in recognition of the large quantity of ongoing reactor designs utilizing high temperature technology. Since Code Case N-201 had not seen a significant revision (except for a minor revision in September, 2006 to change the SA-336 forging reference for 304SS and 316SS to SA-965 in Tables 1.2(a) and 1.2(b), and some minor editorial changes) since December 1994, identifying recommended updates to support the current high temperature Core Support Structure (CSS) designs and potential new designs was important. As anticipated, the Task 4 effort identified a number of Code Case N-201 issues. Items requiring further consideration range from addressing apparent inconsistencies in definitions and certain material properties between CC-N-201 and Subsection NH, to inclusion of additional materials to provide the designer more flexibility of design. Task 4 developed a design parameter survey that requested input from the CSS designers of ongoing high temperature gas cooled reactor metallic core support designs. The responses to the survey provided Task 4 valuable input to identify the design operating parameters and future needs of the CSS designers. Types of materials, metal temperature, time of exposure, design pressure, design life, and fluence levels were included in the Task 4 survey responses. The results of the survey are included in this report. This research proves that additional work must be done to update Code Case N-201. Task 4 activities provide the framework for the Code Case N-201 update and future work to provide input on materials. Candidate

Differential Expression of Ccn4 and Other Genes Between Metastatic and Non-metastatic EL4 Mouse Lymphoma Cells.

Science.gov (United States)

Chahal, Manpreet S; Ku, H Teresa; Zhang, Zhihong; Legaspi, Christian M; Luo, Angela; Hopkins, Mandi M; Meier, Kathryn E

Previous work characterized variants of the EL4 murine lymphoma cell line. Some are non-metastatic, and others metastatic, in syngenic mice. In addition, metastatic EL4 cells were stably transfected with phospholipase D2 (PLD2), which further enhanced metastasis. Microarray analyses of mRNA expression was performed for non-metastatic, metastatic, and PLD2-expressing metastatic EL4 cells. Many differences were observed between non-metastatic and metastatic cell lines. One of the most striking new findings was up-regulation of mRNA for the matricellular protein WNT1-inducible signaling pathway protein 1 (CCN4) in metastatic cells; increased protein expression was verified by immunoblotting and immunocytochemistry. Other differentially expressed genes included those for reproductive homeobox 5 (Rhox5; increased in metastatic) and cystatin 7 (Cst7; decreased in metastatic). Differences between PLD2-expressing and parental cell lines were limited but included the signaling proteins Ras guanyl releasing protein 1 (RGS18; increased with PLD2) and suppressor of cytokine signaling 2 (SOCS2; decreased with PLD2). The results provide insights into signaling pathways potentially involved in conferring metastatic ability on lymphoma cells. Copyright© 2016, International Institute of Anticancer Research (Dr. John G. Delinasios), All rights reserved.

Comparison of aerosol and cloud condensation nuclei between wet and dry seasons in Guangzhou, southern China.

Science.gov (United States)

Duan, Junyan; Tao, Jun; Wu, Yunfei; Cheng, Tiantao; Zhang, Renjian; Wang, Yanyu; Zhu, Hailin; Xie, Xin; Liu, Yuehui; Li, Xiang; Kong, Lingdong; Li, Mei; He, Qianshan

2017-12-31

Cloud condensation nuclei (CCN), condensation nuclei (CN) and aerosol chemical composition were measured simultaneously at an urban site of Guangzhou from July to August 2015 and in January 2016, and the seasonal variations of aerosol activated fractions (N CCN /N CN ) as well as their relevant influence factors were further studied accordingly. N CN is generally higher in winter (dry season), whereas N CCN and N CCN /N CN are mostly higher in summer (wet season) instead. In particular, N CCN and N CCN /N CN are much lower at smaller supersaturation levels (SStransportation, meteorological conditions, etc., also contribute to the variations of N CCN and N CCN /N CN. Particles from the local source or local-oceanic combination source cast influence on CN and CCN significantly, while the pollutants originating from and crossing over distant polluted areas contribute largely to CCN/CN. N CN and N CCN are relatively higher under pollution-free conditions in summertime and polluted conditions in wintertime, but N CCN /N CN is just the opposite. On various polluted conditions, aerosol CCN activities are greatly discrepant between summer and winter, especially during mist or heavy haze periods. The results imply that anthropogenic pollutants exert critical impacts on aerosol CCN activation. Copyright © 2017 Elsevier B.V. All rights reserved.

Flavor Profile of Clone CCN 51 Cocoa (Theobroma cacao L. Produced in Three Farms Municipality of San Vicente de Chucurí

Directory of Open Access Journals (Sweden)

Lucas Fernando Quintana Fuentes

2011-04-01

Full Text Available Colombia is one of the bigger producers of cocoa in America, the production is consumed in the totally in internal form. The department of Santander is me bigger producer of cocoa in Colombia and the municipality of San Vicente de Chucuri is considered the cocoa capital of the country. Actually theColombian federation of cocoa (Fedecacao together with the Unad have an agreement of cooperation for the strengthening of the evaluating capacity of the sensorial quality of the cocoa.In the process of evaluation of the sensorial quality of the cocoa liqueur (clone CNN 51 we established the needs in accordance to the current regulations for the implementation of a panel of trained judges, from the preselection, selection, specific training, training evaluation and the evaluation of the final samples ofthree representative farms in where is cultivated the clone CCN 51 in San Vicente del Chucuri.We conform a group of eleven trained judges and we obtained the sensorial profile of flavor for the samples for three representative farms of the municipality.

Global synthesis of long-term cloud condensation nuclei observations

Science.gov (United States)

Schmale, Julia; Henning, Silvia; Stratmann, Frank; Henzing, Bas; Schlag, Patrick; Aalto, Pasi; Keskinen, Helmi; Sellegri, Karine; Ovadnevaite, Jurgita; Krüger, Mira; Jefferson, Anne; Whitehead, James; Carslaw, Ken; Yum, Seong Soo; Kristensson, Adam; Baltensperger, Urs; Gysel, Martin

2016-04-01

Cloud condensation nuclei (CCN) are aerosol particles with the ability to activate into droplets at a given super saturation and therefore influence the microphysical and optical properties of clouds. To predict cloud radiative properties understanding the spatial and temporal variability of CCN concentrations in different environments is important. However, currently, the effects of atmospheric particles on changes in cloud radiative forcing are still the largest contribution of uncertainty in climate forcing prediction (IPCC, 2013). Numerous intensive field campaigns have already explored detailed characteristics of CCN in many locations around the world. However, these rather short-term observations can generally not address seasonal or inter-annual variations and a comparison between campaign sites is difficult due to the higher influence of specific environmental circumstances on short-term measurements results. Here, we present results of more long-term CCN and aerosol number concentrations as well as size distribution data covering at least one full year between 2006 and 2014. The 12 locations include ACTRIS stations (http://www.actris.net/) in Europe, and further sites in North America, Brazil and Korea. The sites are located in different environments allowing for temporal and spatial characterization of CCN variability in different atmospheric regimes. Those include marine, remote-continental, boreal forest, rain forest, Arctic and monsoon-influenced environments, as well as boundary layer and free tropospheric conditions. The aerosol populations and their activation behavior show significant differences across the stations. While peak concentrations of CCN are observed in summer at the high altitude sites, in the Arctic the highest concentrations occur during the Haze period in spring. The rural-marine and rural-continental sites exhibit similar CCN concentration characteristics with a relatively flat annual cycle. At some stations, e.g. in the boreal

Long-term cloud condensation nuclei number concentration, particle number size distribution and chemical composition measurements at regionally representative observatories

Directory of Open Access Journals (Sweden)

J. Schmale

2018-02-01

Full Text Available Aerosol–cloud interactions (ACI constitute the single largest uncertainty in anthropogenic radiative forcing. To reduce the uncertainties and gain more confidence in the simulation of ACI, models need to be evaluated against observations, in particular against measurements of cloud condensation nuclei (CCN. Here we present a data set – ready to be used for model validation – of long-term observations of CCN number concentrations, particle number size distributions and chemical composition from 12 sites on 3 continents. Studied environments include coastal background, rural background, alpine sites, remote forests and an urban surrounding. Expectedly, CCN characteristics are highly variable across site categories. However, they also vary within them, most strongly in the coastal background group, where CCN number concentrations can vary by up to a factor of 30 within one season. In terms of particle activation behaviour, most continental stations exhibit very similar activation ratios (relative to particles  > 20 nm across the range of 0.1 to 1.0 % supersaturation. At the coastal sites the transition from particles being CCN inactive to becoming CCN active occurs over a wider range of the supersaturation spectrum. Several stations show strong seasonal cycles of CCN number concentrations and particle number size distributions, e.g. at Barrow (Arctic haze in spring, at the alpine stations (stronger influence of polluted boundary layer air masses in summer, the rain forest (wet and dry season or Finokalia (wildfire influence in autumn. The rural background and urban sites exhibit relatively little variability throughout the year, while short-term variability can be high especially at the urban site. The average hygroscopicity parameter, κ, calculated from the chemical composition of submicron particles was highest at the coastal site of Mace Head (0.6 and lowest at the rain forest station ATTO (0.2–0.3. We performed closure

Investigating microenvironmental regulation of human chordoma cell behaviour.

Directory of Open Access Journals (Sweden)

Priya Patel

Full Text Available The tumour microenvironment is complex and composed of many different constituents, including matricellular proteins such as connective tissue growth factor (CCN2, and is characterized by gradients in oxygen levels. In various cancers, hypoxia and CCN2 promote stem and progenitor cell properties, and regulate the proliferation, migration and phenotype of cancer cells. Our study was aimed at investigating the effects of hypoxia and CCN2 on chordoma cells, using the human U-CH1 cell line. We demonstrate that under basal conditions, U-CH1 cells express multiple CCN family members including CCN1, CCN2, CCN3 and CCN5. Culture of U-CH1 cells in either hypoxia or in the presence of recombinant CCN2 peptide promoted progenitor cell-like characteristics specific to the notochordal tissue of origin. Specifically, hypoxia induced the most robust increase in progenitor-like characteristics in U-CH1 cells, including increased expression of the notochord-associated markers T, CD24, FOXA1, ACAN and CA12, increased cell growth and tumour-sphere formation, and a decrease in the percentage of vacuolated cells present in the heterogeneous population. Interestingly, the effects of recombinant CCN2 peptide on U-CH1 cells were more pronounced under normoxia than hypoxia, promoting increased expression of CCN1, CCN2, CCN3 and CCN5, the notochord-associated markers SOX5, SOX6, T, CD24, and FOXA1 as well as increased tumour-sphere formation. Overall, this study highlights the importance of multiple factors within the tumour microenvironment and how hypoxia and CCN2 may regulate human chordoma cell behaviour.

Expression of connective tissue growth factor in male breast cancer: clinicopathologic correlations and prognostic value.

Science.gov (United States)

Lacle, Miangela M; van Diest, Paul J; Goldschmeding, Roel; van der Wall, Elsken; Nguyen, Tri Q

2015-01-01

Connective tissue growth factor (CTGF/CCN2) is a member of the CCN family of secreted proteins that are believed to play an important role in the development of neoplasia. In particular, CTGF has been reported to play an important role in mammary tumorigenesis and to have prognostic value in female breast cancer (FBC). The aim of the present study was to investigate clinicopathologic correlations and prognostic value of CTGF in male breast cancer (MBC) and to compare these findings with FBC. For this, we studied CTGF protein expression by immunohistochemistry in 109 MBC cases and 75 FBC cases. In MBC, stromal CTGF expression was seen in the majority of the cases 78% (85/109) with high expression in 31/109 cases (28.4%), but expression in tumor cells was only seen in 9.2% (10/109) of cases. High stromal CTGF expression correlated with high grade and high proliferation index (>15%) assessed by MIB-1 immunohistochemical staining. CTGF expression in tumor epithelial cells did not correlate with any of the clinicopathologic features. In FBC, stromal CTGF expression positively correlated with mitotic count and tumor CTGF expression was associated with triple negative status of the tumor (p = 0.002). Neither stromal nor tumor epithelial cell CTGF expression had prognostic value in MBC and FBC. In conclusion, stromal CTGF expression was seen in a high percentage of MBC and was correlated with high grade and high proliferation index. In view of the important role of the microenvironment in cancer progression, this might suggest that stromal CTGF could be an interesting target for novel therapies and molecular imaging. However, the lack of association with prognosis warrants caution. The potential role of CTGF as a therapeutic target for triple negative FBC deserves to be further studied.

Laboratory Studies of the Reactive Chemistry and Changing CCN Properties of Secondary Organic Aerosol, Including Model Development

Energy Technology Data Exchange (ETDEWEB)

Scot Martin

2013-01-31

The chemical evolution of secondary-organic-aerosol (SOA) particles and how this evolution alters their cloud-nucleating properties were studied. Simplified forms of full Koehler theory were targeted, specifically forms that contain only those aspects essential to describing the laboratory observations, because of the requirement to minimize computational burden for use in integrated climate and chemistry models. The associated data analysis and interpretation have therefore focused on model development in the framework of modified kappa-Koehler theory. Kappa is a single parameter describing effective hygroscopicity, grouping together several separate physicochemical parameters (e.g., molar volume, surface tension, and van't Hoff factor) that otherwise must be tracked and evaluated in an iterative full-Koehler equation in a large-scale model. A major finding of the project was that secondary organic materials produced by the oxidation of a range of biogenic volatile organic compounds for diverse conditions have kappa values bracketed in the range of 0.10 +/- 0.05. In these same experiments, somewhat incongruently there was significant chemical variation in the secondary organic material, especially oxidation state, as was indicated by changes in the particle mass spectra. Taken together, these findings then support the use of kappa as a simplified yet accurate general parameter to represent the CCN activation of secondary organic material in large-scale atmospheric and climate models, thereby greatly reducing the computational burden while simultaneously including the most recent mechanistic findings of laboratory studies.

Evidence of Chemical Cloud Processing from In Situ Measurements in the Polluted Marine Environment

Science.gov (United States)

Hudson, J. G.; Noble, S. R., Jr.

2017-12-01

Chemical cloud processing alters activated cloud condensation nuclei (CCN). Aqueous oxidation of trace gases dissolved within cloud droplets adds soluble material. As most cloud droplets evaporate, the residual material produces CCN that are larger and with a different hygroscopicity (κ). This improves the CCN, lowering the critical supersaturation (Sc), making it more easily activated. This process separates the processed (accumulation) and unprocessed (Aitken) modes creating bimodal CCN distributions (Hudson et al., 2015). Various measurements made during the MArine Stratus/stratocumulus Experiment (MASE), including CCN, exhibited aqueous processing signals. Particle size distributions; measured by a differential mobility analyzer; were compared with CCN distributions; measured by the Desert Research Institute CCN spectrometer; by converting size to Sc using κ to overlay concurrent distributions. By tuning each mode to the best agreement, κ for each mode is determined; processed κ (κp), unprocessed κ (κu). In MASE, 59% of bimodal distributions had different κ for the two modes indicating dominance of chemical processing via aqueous oxidation. This is consistent with Hudson et al. (2015). Figure 1A also indicates chemical processing with larger κp between 0.35-0.75. Processed CCN had an influx of soluble material from aqueous oxidation which increased κp versus κu. Above 0.75 κp is lower than κu (Fig. 1A). When κu is high and sulfate material is added, κp tends towards κ of the added material. Thus, κp is reduced by additional material that is less soluble than the original material. Chemistry measurements in MASE also indicate in-cloud aqueous oxidation (Fig. 1B and 1C). Higher fraction of CCN concentrations in the processed mode are also associated with larger amounts of sulfates (Fig. 1B, red) and nitrates (Fig. 1C, orange) while SO2 (Fig. 1B, black) and O3 (Fig. 1C, blue) have lower amounts. This larger amount of sulfate is at the expense of

Effects of turbulence on warm clouds and precipitation with various aerosol concentrations

Science.gov (United States)

Lee, Hyunho; Baik, Jong-Jin; Han, Ji-Young

2015-02-01

This study investigates the effects of turbulence-induced collision enhancement (TICE) on warm clouds and precipitation by changing the cloud condensation nuclei (CCN) number concentration using a two-dimensional dynamic model with bin microphysics. TICE is determined according to the Taylor microscale Reynolds number and the turbulent dissipation rate. The thermodynamic sounding used in this study is characterized by a warm and humid atmosphere with a capping inversion layer, which is suitable for simulating warm clouds. For all CCN concentrations, TICE slightly reduces the liquid water path during the early stage of cloud development and accelerates the onset of surface precipitation. However, changes in the rainwater path and in the amount of surface precipitation that are caused by TICE depend on the CCN concentrations. For high CCN concentrations, the mean cloud drop number concentration (CDNC) decreases and the mean effective radius increases due to TICE. These changes cause an increase in the amount of surface precipitation. However, for low CCN concentrations, changes in the mean CDNC and in the mean effective radius induced by TICE are small and the amount of surface precipitation decreases slightly due to TICE. A decrease in condensation due to the accelerated coalescence between droplets explains the surface precipitation decrease. In addition, an increase in the CCN concentration can lead to an increase in the amount of surface precipitation, and the relationship between the CCN concentration and the amount of surface precipitation is affected by TICE. It is shown that these results depend on the atmospheric relative humidity.

Connective tissue growth factor (CTGF/CCN2 is negatively regulated during neuron-glioblastoma interaction.

Directory of Open Access Journals (Sweden)

Luciana F Romão

Full Text Available Connective-tissue growth factor (CTGF/CCN2 is a matricellular-secreted protein involved in complex processes such as wound healing, angiogenesis, fibrosis and metastasis, in the regulation of cell proliferation, migration and extracellular matrix remodeling. Glioblastoma (GBM is the major malignant primary brain tumor and its adaptation to the central nervous system microenvironment requires the production and remodeling of the extracellular matrix. Previously, we published an in vitro approach to test if neurons can influence the expression of the GBM extracellular matrix. We demonstrated that neurons remodeled glioma cell laminin. The present study shows that neurons are also able to modulate CTGF expression in GBM. CTGF immnoreactivity and mRNA levels in GBM cells are dramatically decreased when these cells are co-cultured with neonatal neurons. As proof of particular neuron effects, neonatal neurons co-cultured onto GBM cells also inhibit the reporter luciferase activity under control of the CTGF promoter, suggesting inhibition at the transcription level. This inhibition seems to be contact-mediated, since conditioned media from embryonic or neonatal neurons do not affect CTGF expression in GBM cells. Furthermore, the inhibition of CTGF expression in GBM/neuronal co-cultures seems to affect the two main signaling pathways related to CTGF. We observed inhibition of TGFβ luciferase reporter assay; however phopho-SMAD2 levels did not change in these co-cultures. In addition levels of phospho-p44/42 MAPK were decreased in co-cultured GBM cells. Finally, in transwell migration assay, CTGF siRNA transfected GBM cells or GBM cells co-cultured with neurons showed a decrease in the migration rate compared to controls. Previous data regarding laminin and these results demonstrating that CTGF is down-regulated in GBM cells co-cultured with neonatal neurons points out an interesting view in the understanding of the tumor and cerebral microenvironment

Production of extremely low volatile organic compounds from biogenic emissions: Measured yields and atmospheric implications.

Science.gov (United States)

Jokinen, Tuija; Berndt, Torsten; Makkonen, Risto; Kerminen, Veli-Matti; Junninen, Heikki; Paasonen, Pauli; Stratmann, Frank; Herrmann, Hartmut; Guenther, Alex B; Worsnop, Douglas R; Kulmala, Markku; Ehn, Mikael; Sipilä, Mikko

2015-06-09

Oxidation products of monoterpenes and isoprene have a major influence on the global secondary organic aerosol (SOA) burden and the production of atmospheric nanoparticles and cloud condensation nuclei (CCN). Here, we investigate the formation of extremely low volatility organic compounds (ELVOC) from O3 and OH radical oxidation of several monoterpenes and isoprene in a series of laboratory experiments. We show that ELVOC from all precursors are formed within the first minute after the initial attack of an oxidant. We demonstrate that under atmospherically relevant concentrations, species with an endocyclic double bond efficiently produce ELVOC from ozonolysis, whereas the yields from OH radical-initiated reactions are smaller. If the double bond is exocyclic or the compound itself is acyclic, ozonolysis produces less ELVOC and the role of the OH radical-initiated ELVOC formation is increased. Isoprene oxidation produces marginal quantities of ELVOC regardless of the oxidant. Implementing our laboratory findings into a global modeling framework shows that biogenic SOA formation in general, and ELVOC in particular, play crucial roles in atmospheric CCN production. Monoterpene oxidation products enhance atmospheric new particle formation and growth in most continental regions, thereby increasing CCN concentrations, especially at high values of cloud supersaturation. Isoprene-derived SOA tends to suppress atmospheric new particle formation, yet it assists the growth of sub-CCN-size primary particles to CCN. Taking into account compound specific monoterpene emissions has a moderate effect on the modeled global CCN budget.

Vertical microphysical profiles of convective clouds as a tool for obtaining aerosol cloud-mediated climate forcings

Energy Technology Data Exchange (ETDEWEB)

Rosenfeld, Daniel [Hebrew Univ. of Jerusalem (Israel)

2015-12-23

Quantifying the aerosol/cloud-mediated radiative effect at a global scale requires simultaneous satellite retrievals of cloud condensation nuclei (CCN) concentrations and cloud base updraft velocities (Wb). Hitherto, the inability to do so has been a major cause of high uncertainty regarding anthropogenic aerosol/cloud-mediated radiative forcing. This can be addressed by the emerging capability of estimating CCN and Wb of boundary layer convective clouds from an operational polar orbiting weather satellite. Our methodology uses such clouds as an effective analog for CCN chambers. The cloud base supersaturation (S) is determined by Wb and the satellite-retrieved cloud base drop concentrations (Ndb), which is the same as CCN(S). Developing and validating this methodology was possible thanks to the ASR/ARM measurements of CCN and vertical updraft profiles. Validation against ground-based CCN instruments at the ARM sites in Oklahoma, Manaus, and onboard a ship in the northeast Pacific showed a retrieval accuracy of ±25% to ±30% for individual satellite overpasses. The methodology is presently limited to boundary layer not raining convective clouds of at least 1 km depth that are not obscured by upper layer clouds, including semitransparent cirrus. The limitation for small solar backscattering angles of <25º restricts the satellite coverage to ~25% of the world area in a single day. This methodology will likely allow overcoming the challenge of quantifying the aerosol indirect effect and facilitate a substantial reduction of the uncertainty in anthropogenic climate forcing.

Potential indirect effects of aerosol on tropical cyclone development

Science.gov (United States)

Krall, Geoffrey

Observational and model evidence suggest that a 2008 Western Pacific typhoon (NURI) came into contact with and ingested elevated concentrations of aerosol as it neared the Chinese coast. This study uses a regional model with two-moment bin emulating microphysics to simulate the typhoon as it enters the field of elevated aerosol concentration. A continental field of cloud condensation nuclei (CCN) was prescribed based on satellite and global aerosol model output, then increased for further sensitivity tests. The typhoon was simulated for 96 hours beginning 17 August 2008, the final 60 of which were under varying CCN concentrations as it neared the Philippines and coastal China. The model was initialized with both global reanalysis model data and irregularly spaced dropsonde data from a 2008 observational campaign using an objective analysis routine. At 36 hours, the internal nudging of the model was switched off and allowed to evolve on its own. As the typhoon entered the field of elevated CCN in the sensitivity tests, the presence of additional CCN resulted in a significant perturbation of windspeed, convective fluxes, and hydrometeor species behavior. Initially ingested in the outer rainbands of the storm, the additional CCN resulted in an initial damping and subsequent invigoration of convection. The increase in convective fluxes strongly lag-correlates with increased amounts of supercooled liquid water within the storm domain. As the convection intensified in the outer rainbands the storm drifted over the developing cold-pools, affecting the inflow of air into the convective towers of the typhoon. Changes in the timing and amount of rain produced in each simulation resulted in differing cold-pool strengths and size. The presence of additional CCN increased resulted in an amplification of convection within the storm, except for the extremely high CCN concentration simulation, which showed a damped convection due to the advection of pristine ice away from the

Valence shell threshold photoelectron spectroscopy of the CHxCN (x = 0-2) and CNC radicals.

Science.gov (United States)

Garcia, Gustavo A; Krüger, Julia; Gans, Bérenger; Falvo, Cyril; Coudert, Laurent H; Loison, Jean-Christophe

2017-07-07

We present the photoelectron spectroscopy of four radical species, CH x CN (x = 0-2) and CNC, formed in a microwave discharge flow-tube reactor by consecutive H abstractions from CH 3 CN (CH x CN + F → CH x-1 CN + HF (x = 1-3)). The spectra were obtained combining tunable vacuum ultraviolet synchrotron radiation with double imaging electron/ion coincidence techniques, which yielded mass-selected threshold photoelectron spectra. The results obtained for H 2 CCN complement existing ones while for the other radicals the data represent the first observation of their (single-photon) ionizing transitions. In the case of H 2 CCN, Franck-Condon calculations have been performed in order to assign the vibrational structure of the X + 1 A 1 ←X 2 B 1 ionizing transition. A similar treatment for the HCCN, CCN, and CNC radicals appeared to be more complicated mainly because a Renner-Teller effect strongly affects the vibrational levels of the ground electronic state of the HCCN + , CCN, and CNC species. Nevertheless, the first adiabatic ionization energies of these radicals are reported and compared to our ab initio calculated values, leading to new values for enthalpies of formation (Δ f H 298 0 (HCCN + (X 2 A ' ))=1517±12kJmol -1 ,Δ f H 298 0 (CCN(X 2 Π))=682±13kJmol -1 , and Δ f H 298 0 (CNC(X 2 Πg))=676±12kJmol -1 ), which are of fundamental importance for astrochemistry.

Increased fibroblast functionality on CNN2-loaded titania nanotubes

Directory of Open Access Journals (Sweden)

Wei HB

2012-02-01

Full Text Available Hongbo Wei*, Shuyi Wu*, Zhihong Feng, Wei Zhou, Yan Dong, Guofeng Wu, Shizhu Bai, Yimin Zhao Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, People's Republic of China *These authors contributed equally to this workAbstract: Infection and epithelial downgrowth are major problems associated with maxillofacial percutaneous implants. These complications are mainly due to the improper closure of the implant–skin interface. Therefore, designing a percutaneous implant that better promotes the formation of a stable soft tissue biologic seal around percutaneous sites is highly desirable. Additionally, the fibroblast has been proven to play an important role in the formation of biologic seals. In this study, titania nanotubes were filled with 11.2 kDa C-terminal CCN2 (connective tissue growth factor fragment, which could exert full CCN2 activity to increase the biological functionality of fibroblasts. This drug delivery system was fabricated on a titanium implant surface. CCN2 was loaded into anodized titania nanotubes using a simplified lyophilization method and the loading efficiency was approximately 80%. Then, the release kinetics of CCN2 from these nanotubes was investigated. Furthermore, the influence of CCN2-loaded titania nanotubes on fibroblast functionality was examined. The results revealed increased fibroblast adhesion at 0.25, 0.5, 1, 2, 4, and 24 hours, increased fibroblast viability over the course of 5 days, as well as enhanced actin cytoskeleton organization on CCN2-loaded titania nanotubes surfaces compared to uncoated, unmodified counterparts. Therefore, the results from this in vitro study demonstrate that CCN2-loaded titania nanotubes have the ability to increase fibroblast functionality and should be further studied as a method of promoting the formation of a stable soft tissue biologic seal around percutaneous sites.Keywords: anodization, titania nanotubes, adhesion, connective

Correlation Of Giant Nuclei With Cloud Droplet Concentration

Science.gov (United States)

Jha, V.; Hudson, J. G.; Noble, S.

2011-12-01

The effect of giant nuclei (GN; larger than 1 micrometer particles produced by wind on the ocean surface) on warm rain has been debated for decades. During RICO (Rain in Cumulus over the Ocean) Hudson et al. (2011) found a negative correlation (R) between CCN concentrations at 1% supersaturation (S) and large cloud droplet concentrations (Fig. 1A). This reversal from positive R for CCN with total (or small) cloud droplet concentrations (left side of Fig. 1A) was explained by the greater competition for condensate, which thus limits droplet sizes when CCN concentrations are higher. The negative R increased in magnitude with altitude, and the droplet size where the maximum negative R occurred increased with altitude (Fig. 1A). However, at all altitudes this negative R decreased in magnitude for even larger cloud and drizzle drops (right side of Fig. 1A except highest altitude). The decrease in magnitude of the negative R was greater for increasing drop sizes at higher altitudes. Thus, at the higher altitudes, R for CCN with large drizzle drops was of low negative magnitude and even positive at the highest RICO altitudes. The disparity between CCN and drizzle drop concentrations precluded a causal relationship. But the high R between GN and drizzle drop concentrations at the highest altitudes (Fig. 1B) and the comparable concentrations indicated that GN were engendering drizzle. This is supported by the increasing R with altitude of the GN-drizzle drop R (right side of Fig. 1B). The conclusion of a GN-drizzle connection is also supported by the fact that CCN concentrations should inhibit drizzle. This analysis of Hudson et al. (2011) is here expanded to include correlations of CCN concentrations at lower S with cloud and drizzle drop concentrations to investigate intermediate relationships; i.e., between large nuclei (i.e., 0.1-1 micrometer; critical S 0.1-0.01%) and drizzle drop concentrations. A shortcoming of Hudson et al. (2011) was the small number of high

When is an INP not an INP?

Science.gov (United States)

Simpson, Emma; Connolly, Paul; McFiggans, Gordon

2016-04-01

Processes such as precipitation and radiation depend on the concentration and size of different hydrometeors within clouds therefore it is important to accurately predict them in weather and climate models. A large fraction of clouds present in our atmosphere are mixed phase; contain both liquid and ice particles. The number of drops and ice crystals present in mixed phase clouds strongly depends on the size distribution of aerosols. Cloud condensation nuclei (CCN), a subset of atmospheric aerosol particles, are required for liquid drops to form in the atmosphere. These particles are ubiquitous in the atmosphere. To nucleate ice particles in mixed phase clouds ice nucleating particles (INP) are required. These particles are rarer than CCN. Here we investigate the case where CCN and INPs are in direct competition with each other for water vapour within a cloud. Focusing on the immersion and condensation modes of freezing (where an INP must be immersed within a liquid drop before it can freeze) we show that the presence of CCN can suppress the formation of ice. CCN are more hydrophilic than IN and as such are better able to compete for water vapour than, typically insoluble, INPs. Therefore water is more likely to condense onto a CCN than INP, leaving the INP without enough condensed water on it to be able to freeze in the immersion or condensation mode. The magnitude of this suppression effect strongly depends on a currently unconstrained quantity. Here we refer to this quantity as the critical mass of condensed water required for freezing, Mwc. Mwc is the threshold amount of water that must be condensed onto a INP before it can freeze in the immersion or condensation mode. Using the detailed cloud parcel model, Aerosol-Cloud-Precipiation-Interaction Model (ACPIM), developed at the University of Manchester we show that if only a small amount of water is required for freezing there is little suppression effect and if a large amount of water is required there is a

Preliminary energy demand studies for Ireland: base case and high case for 1980, 1985 and 1990

Energy Technology Data Exchange (ETDEWEB)

Henry, E W

1981-01-01

The framework of the Base Case and the High Case for 1990 for Ireland, related to the demand modules of the medium-term European Communities (EC) Energy Model, is described. The modules are: Multi-national Macre-economic Module (EURECA); National Input-Output Model (EXPLOR); and National Energy Demand Model (EDM). The final results of the EXPLOR and EDM are described; one set related to the Base Case and the other related to the High Case. The forecast or projection is termed Base Case because oil prices are assumed to increase with general price inflation, at the same rate. The other forecast is termed High Case because oil prices are assumed to increase at 5% per year more rapidly than general price inflation. The EXPLOR-EDM methodology is described. The lack of data on energy price elasticities for Ireland is noted. A comparison of the Base Case with the High Case is made. (MCW)

Topically applied connective tissue growth factor/CCN2 improves diabetic preclinical cutaneous wound healing: potential role for CTGF in human diabetic foot ulcer healing.

Science.gov (United States)

Henshaw, F R; Boughton, P; Lo, L; McLennan, S V; Twigg, S M

2015-01-01

Topical application of CTGF/CCN2 to rodent diabetic and control wounds was examined. In parallel research, correlation of CTGF wound fluid levels with healing rate in human diabetic foot ulcers was undertaken. Full thickness cutaneous wounds in diabetic and nondiabetic control rats were treated topically with 1 μg rhCTGF or vehicle alone, on 2 consecutive days. Wound healing rate was observed on day 14 and wound sites were examined for breaking strength and granulation tissue. In the human study across 32 subjects, serial CTGF regulation was analyzed longitudinally in postdebridement diabetic wound fluid. CTGF treated diabetic wounds had an accelerated closure rate compared with vehicle treated diabetic wounds. Healed skin withstood more strain before breaking in CTGF treated rat wounds. Granulation tissue from CTGF treatment in diabetic wounds showed collagen IV accumulation compared with nondiabetic animals. Wound α-smooth muscle actin was increased in CTGF treated diabetic wounds compared with untreated diabetic wounds, as was macrophage infiltration. Endogenous wound fluid CTGF protein rate of increase in human diabetic foot ulcers correlated positively with foot ulcer healing rate (r = 0.406; P diabetic foot ulcers.

Hygroscopic properties of atmospheric particles emitted during wintertime biomass burning episodes in Athens

Science.gov (United States)

Psichoudaki, Magda; Nenes, Athanasios; Florou, Kalliopi; Kaltsonoudis, Christos; Pandis, Spyros N.

2018-04-01

This study explores the Cloud Condensation Nuclei (CCN) activity of atmospheric particles during intense biomass burning periods in an urban environment. During a one-month campaign in the center of Athens, Greece, a CCN counter coupled with a Scanning Mobility Particle Sizer (SMPS) and a high resolution Aerosol Mass Spectrometer (HR-AMS) were used to measure the size-resolved CCN activity and composition of the atmospheric aerosols. During the day, the organic fraction of the particles was more than 50%, reaching almost 80% at night, when the fireplaces were used. Positive Matrix Factorization (PMF) analysis revealed 4 factors with biomass burning being the dominant source after 18:00 until the early morning. The CCN-based overall hygroscopicity parameter κ ranged from 0.15 to 0.25. During the night, when the biomass burning organic aerosol (bbOA) dominated, the hygroscopicity parameter for the mixed organic/inorganic particles was on average 0.16. The hygroscopicity of the biomass-burning organic particles was 0.09, while the corresponding average value for all organic particulate matter during the campaign was 0.12.

Cloud condensation nuclei closure study on summer arctic aerosol

Science.gov (United States)

Martin, M.; Chang, R. Y.-W.; Sierau, B.; Sjogren, S.; Swietlicki, E.; Abbatt, J. P. D.; Leck, C.; Lohmann, U.

2011-11-01

We present an aerosol - cloud condensation nuclei (CCN) closure study on summer high Arctic aerosol based on measurements that were carried out in 2008 during the Arctic Summer Cloud Ocean Study (ASCOS) on board the Swedish ice breaker Oden. The data presented here were collected during a three-week time period in the pack ice (>85° N) when the icebreaker Oden was moored to an ice floe and drifted passively during the most biological active period into autumn freeze up conditions. CCN number concentrations were obtained using two CCN counters measuring at different supersaturations. The directly measured CCN number concentration was then compared with a CCN number concentration calculated using both bulk aerosol mass composition data from an aerosol mass spectrometer (AMS) and aerosol number size distributions obtained from a differential mobility particle sizer, assuming κ-Köhler theory, surface tension of water and an internally mixed aerosol. The last assumption was supported by measurements made with a hygroscopic tandem differential mobility analyzer (HTDMA) for particles >70 nm. For the two highest measured supersaturations, 0.73 and 0.41%, closure could not be achieved with the investigated settings concerning hygroscopicity and density. The calculated CCN number concentration was always higher than the measured one for those two supersaturations. This might be caused by a relative larger insoluble organic mass fraction of the smaller particles that activate at these supersaturations, which are thus less good CCN than the larger particles. On average, 36% of the mass measured with the AMS was organic mass. At 0.20, 0.15 and 0.10% supersaturation, closure could be achieved with different combinations of hygroscopic parameters and densities within the uncertainty range of the fit. The best agreement of the calculated CCN number concentration with the observed one was achieved when the organic fraction of the aerosol was treated as nearly water insoluble

Airborne cloud condensation nuclei measurements during the 2006 Texas Air Quality Study

Science.gov (United States)

Asa-Awuku, Akua; Moore, Richard H.; Nenes, Athanasios; Bahreini, Roya; Holloway, John S.; Brock, Charles A.; Middlebrook, Ann M.; Ryerson, Thomas B.; Jimenez, Jose L.; Decarlo, Peter F.; Hecobian, Arsineh; Weber, Rodney J.; Stickel, Robert; Tanner, Dave J.; Huey, Lewis G.

2011-06-01

Airborne measurements of aerosol and cloud condensation nuclei (CCN) were conducted aboard the National Oceanic and Atmospheric Administration WP-3D platform during the 2006 Texas Air Quality Study/Gulf of Mexico Atmospheric Composition and Climate Study (TexAQS/GoMACCS). The measurements were conducted in regions influenced by industrial and urban sources. Observations show significant local variability of CCN activity (CCN/CN from 0.1 to 0.5 at s = 0.43%), while variability is less significant across regional scales (˜100 km × 100 km; CCN/CN is ˜0.1 at s = 0.43%). CCN activity can increase with increasing plume age and oxygenated organic fraction. CCN measurements are compared to predictions for a number of mixing state and composition assumptions. Mixing state assumptions that assumed internally mixed aerosol predict CCN concentrations well. Assuming organics are as hygroscopic as ammonium sulfate consistently overpredicted CCN concentrations. On average, the water-soluble organic carbon (WSOC) fraction is 60 ± 14% of the organic aerosol. We show that CCN closure can be significantly improved by incorporating knowledge of the WSOC fraction with a prescribed organic hygroscopicity parameter (κ = 0.16 or effective κ ˜ 0.3). This implies that the hygroscopicity of organic mass is primarily a function of the WSOC fraction. The overall aerosol hygroscopicity parameter varies between 0.08 and 0.88. Furthermore, droplet activation kinetics are variable and 60% of particles are smaller than the size characteristic of rapid droplet growth.

Effect of vehicular traffic, remote sources and new particle formation on the activation properties of cloud condensation nuclei in the megacity of São Paulo, Brazil

Directory of Open Access Journals (Sweden)

C. E. Souto-Oliveira

2016-11-01

Full Text Available Atmospheric aerosol is the primary source of cloud condensation nuclei (CCN. The microphysics and chemical composition of aerosols can affect cloud development and the precipitation process. Among studies conducted in Latin America, only a handful have reported the impact of urban aerosol on CCN activation parameters such as activation ratio (AR and activation diameter (Dact. With over 20 million inhabitants, the Metropolitan Area of São Paulo (MASP is the largest megacity in South America. To our knowledge, this is the first study to assess the impact that remote sources and new particle formation (NPF events have on CCN activation properties in a South American megacity. The measurements were conducted in the MASP between August and September 2014. We measured the CCN within the 0.2–1.0 % range of supersaturation, together with particle number concentration (PNC and particle number distribution (PND, as well as trace-element concentrations and black carbon (BC. NPF events were identified on 35 % of the sampling days. Combining multivariate analysis in the form of positive matrix factorization (PMF with an aerosol profile from lidar and HYSPLIT model analyses allowed us to identify the main contribution of vehicular traffic on all days and sea salt and biomass burning from remote regions on 28 and 21 % of the sampling days, respectively. The AR and Dact parameters showed distinct patterns for daytime with intense vehicular traffic and nighttime periods. For example, CCN activation was lower during the daytime than during the nighttime periods, a pattern that was found to be associated mainly with local road-traffic emissions. A decrease in CCN activation was observed on the NPF event days, mainly due to high concentrations of particles with smaller diameters. We also found that aerosols from sea salt, industrial emissions, and biomass burning had minor effects on Dact. For example, nights with biomass burning and vehicular emissions

Effect of vehicular traffic, remote sources and new particle formation on the activation properties of cloud condensation nuclei in the megacity of São Paulo, Brazil

Science.gov (United States)

Souto-Oliveira, Carlos Eduardo; de Fátima Andrade, Maria; Kumar, Prashant; Juliano da Silva Lopes, Fábio; Babinski, Marly; Landulfo, Eduardo

2016-11-01

Atmospheric aerosol is the primary source of cloud condensation nuclei (CCN). The microphysics and chemical composition of aerosols can affect cloud development and the precipitation process. Among studies conducted in Latin America, only a handful have reported the impact of urban aerosol on CCN activation parameters such as activation ratio (AR) and activation diameter (Dact). With over 20 million inhabitants, the Metropolitan Area of São Paulo (MASP) is the largest megacity in South America. To our knowledge, this is the first study to assess the impact that remote sources and new particle formation (NPF) events have on CCN activation properties in a South American megacity. The measurements were conducted in the MASP between August and September 2014. We measured the CCN within the 0.2-1.0 % range of supersaturation, together with particle number concentration (PNC) and particle number distribution (PND), as well as trace-element concentrations and black carbon (BC). NPF events were identified on 35 % of the sampling days. Combining multivariate analysis in the form of positive matrix factorization (PMF) with an aerosol profile from lidar and HYSPLIT model analyses allowed us to identify the main contribution of vehicular traffic on all days and sea salt and biomass burning from remote regions on 28 and 21 % of the sampling days, respectively. The AR and Dact parameters showed distinct patterns for daytime with intense vehicular traffic and nighttime periods. For example, CCN activation was lower during the daytime than during the nighttime periods, a pattern that was found to be associated mainly with local road-traffic emissions. A decrease in CCN activation was observed on the NPF event days, mainly due to high concentrations of particles with smaller diameters. We also found that aerosols from sea salt, industrial emissions, and biomass burning had minor effects on Dact. For example, nights with biomass burning and vehicular emissions showed slightly lower

The Relationship Between Latent Heating, Vertical Velocity, and Precipitation Processes: the Impact of Aerosols on Precipitation in Organized Deep Convective Systems

Science.gov (United States)

Tao, Wei-Kuo; Li, Xiaowen

2016-01-01

A high-resolution, two-dimensional cloud-resolving model with spectral-bin microphysics is used to study the impact of aerosols on precipitation processes in both a tropical oceanic and a midlatitude continental squall line with regard to three processes: latent heating (LH), cold pool dynamics, and ice microphysics. Evaporative cooling in the lower troposphere is found to enhance rainfall in low cloud condensation nuclei (CCN) concentration scenarios in the developing stages of a midlatitude convective precipitation system. In contrast, the tropical case produced more rainfall under high CCN concentrations. Both cold pools and low-level convergence are stronger for those configurations having enhanced rainfall. Nevertheless, latent heat release is stronger (especially after initial precipitation) in the scenarios having more rainfall in both the tropical and midlatitude environment. Sensitivity tests are performed to examine the impact of ice and evaporative cooling on the relationship between aerosols, LH, and precipitation processes. The results show that evaporative cooling is important for cold pool strength and rain enhancement in both cases. However, ice microphysics play a larger role in the midlatitude case compared to the tropics. Detailed analysis of the vertical velocity-governing equation shows that temperature buoyancy can enhance updraftsdowndrafts in the middlelower troposphere in the convective core region; however, the vertical pressure gradient force (PGF) is of the same order and acts in the opposite direction. Water loading is small but of the same order as the net PGF-temperature buoyancy forcing. The balance among these terms determines the intensity of convection.

ZEOLITAS EN LA FERTILIZACIÓN QUÍMICA DEL CACAO CCN-51 ASOCIADO CON CUATRO ESPECIES MADERABLES

Directory of Open Access Journals (Sweden)

Fernando David Sánchez Mora

2014-05-01

Full Text Available Se evaluó el efecto de dos zeolitas comerciales del tipo clinoptilolita: Roca Mágica® (RM y Zeolite C® (ZC, incluidas en la fertilización química sobre la producción y rentabilidad del cacao “CCN-51”, de origen sexual, asociado con cuatro especies maderables [Caoba de montaña (Colubrina arborescens (Mill. Sarg, fernánsanchez (Triplaris cumingiana F., guayacán blanco (Cybistax donell-smithii Rose y laurel prieto (Cordia macrantha Chadat]. En la fertilización fueron utilizados los dos tipos de zeolita (RM y ZC y dos niveles (25 y 30%, más un testigo (sin zeolita. La fertilización se fraccionó en tres partes aplicándose urea, MgSO4, K2O y P2O5. Se empleó un diseño de parcelas divididas con cuatro especies maderables, cinco subtratamientos (tipos y niveles de zeolita y un testigo, en cuatro repeticiones. Se utilizó la prueba de Tukey al 5% de probabilidad. Se midió la fenología del cacao (brotación, floración, fructificación, cherelles wilt, número de mazorcas sanas y producción de cacao en kg ha-1. El mayor número de brotes los emitieron las plantas de cacao asociadas con fernánsanchez en la época lluviosa, posiblemente por la menor cobertura aérea de esta especie. El cacao alcanzó su mayor fructificación en la época lluviosa con las asociaciones fernánsanchez y guayacán y, 30% de ZC. El mayor número de mazorcas sanas, y producción de cacao fue obtenido con la asociación fernánsanchez en la época seca. La mayor rentabilidad se encontró con fernánsanchez y 25% de RM.

Cloud condensation nucleation activities of calcium carbonate and its atmospheric ageing products.

Science.gov (United States)

Tang, M J; Whitehead, J; Davidson, N M; Pope, F D; Alfarra, M R; McFiggans, G; Kalberer, M

2015-12-28

Aerosol particles can serve as cloud condensation nuclei (CCN) to form cloud droplets, and its composition is a main factor governing whether an aerosol particle is an effective CCN. Pure mineral dust particles are poor CCN; however, changes in chemical composition of mineral dust aerosol particles, due to heterogeneous reactions with reactive trace gases in the troposphere, can modify their CCN properties. In this study we investigated the CCN activities of CaCO3 (as a surrogate for mineral dust) and its six atmospheric ageing products: Ca(NO3)2, CaCl2, CaSO4, Ca(CH3SO3)2, Ca(HCOO)2, and Ca(CH3COO)2. CaCO3 has a very low CCN activity with a hygroscopicity parameter (κ) of 0.001-0.003. The CCN activities of its potential atmospheric ageing products are significantly higher. For example, we determined that Ca(NO3)2, CaCl2 and Ca(HCOO)2 have κ values of ∼0.50, similar to that of (NH4)2SO4. Ca(CH3COO)2 has slightly lower CCN activity with a κ value of ∼0.40, and the κ value of CaSO4 is around 0.02. We further show that exposure of CaCO3 particles to N2O5 at 0% relative humidity (RH) significantly enhances their CCN activity, with κ values increasing to around 0.02-0.04. Within the experimental uncertainties, it appears that the variation in exposure to N2O5 from ∼550 to 15,000 ppbv s does not change the CCN activities of aged CaCO3 particles. This observation indicates that the CaCO3 surface may be already saturated at the shortest exposure. We also discussed the atmospheric implications of our study, and suggested that the rate of change in CCN activities of mineral dust particles in the troposphere is important to determine their roles in cloud formation.

Evidence of a reduction in cloud condensation nuclei activity of water-soluble aerosols caused by biogenic emissions in a cool-temperate forest.

Science.gov (United States)

Müller, Astrid; Miyazaki, Yuzo; Tachibana, Eri; Kawamura, Kimitaka; Hiura, Tsutom

2017-08-16

Biogenic organic aerosols can affect cloud condensation nuclei (CCN) properties, and subsequently impact climate change. Large uncertainties exist in how the difference in the types of terrestrial biogenic sources and the abundance of organics relative to sulfate affect CCN properties. For the submicron water-soluble aerosols collected for two years in a cool-temperate forest in northern Japan, we show that the hygroscopicity parameter κ CCN (0.44 ± 0.07) exhibited a distinct seasonal trend with a minimum in autumn (κ CCN  = 0.32-0.37); these κ CCN values were generally larger than that of ambient particles, including water-insoluble fractions. The temporal variability of κ CCN was controlled by the water-soluble organic matter (WSOM)-to-sulfate ratio (R 2  > 0.60), where the significant reduction of κ CCN in autumn was linked to the increased WSOM/sulfate ratio. Positive matrix factorization analysis indicates that α-pinene-derived secondary organic aerosol (SOA) substantially contributed to the WSOM mass (~75%) in autumn, the majority of which was attributable to emissions from litter/soil microbial activity near the forest floor. These findings suggest that WSOM, most likely α-pinene SOA, originated from the forest floor can significantly suppress the aerosol CCN activity in cool-temperate forests, which have implications for predicting climate effects by changes in biogenic emissions in future.

Communication is the key. : Part 2 : Direct to consumer genetics in our future daily life ?

Science.gov (United States)

Perbal, Bernard

2014-12-01

The considerable advances of genome sequencing over the past decades have had a profound impact on our daily life and opened up new avenues for the public to have access to their genetic information and learn more about their ancestry, genealogy and other traits that make each of us unique individuals. A very large number of individual single nucleotide polymorphisms (SNPs) have been associated to diseases whereas others have no known phenotype. For example, among the SNPs mapped within ccn1(cyr61), ccn2(ctgf), ccn3(nov), ccn4(wisp-1), ccn5(wisp-2) and ccn6 (wisp-3), only mutations within ccn4 were associated to PPD (the autosomal recessive skeletal disorder Progressive Pseudorheumatoid Dysplasia). On the occasion of this JCCS special issue on the roles of hormetic responses in adaptation, and response of living species to the modifications of their environment, it appeared that it was a good time to briefly review a topic that has been the subject of passionate discussions for the past few years, that is Direct to Consumer genetic tests (DTC GT). Based on the use of DNA analysis and identification of polymorphisms, DTC GT have been developed by several companies in the USA and in countries where there was no legal obstacle for customers to have direct access to their genetic information and manage their healthcare. Problems that arose and decisions that have been taken by regulatory agencies are presented and discussed in this editorial. The « freeze » of health-oriented DTC GT in the USA neither implies the end of DNA analysis nor « fun » applications, which are not aimed at providing risks estimates for particular illnesses. As shown in the example which is discussed in this editorial, DTC GT for cosmetic applications might be considered a fun application of great interest for companies such as L'Oréal, who recently developed the Makeup Genius mobile application. Other fun applications of DTC GT are discussed but there is no doubt that nothing will stop

Cloud condensation nuclei production associated with atmospheric nucleation: a synthesis based on existing literature and new results

Directory of Open Access Journals (Sweden)

V.-M. Kerminen

2012-12-01

Full Text Available This paper synthesizes the available scientific information connecting atmospheric nucleation with subsequent cloud condensation nuclei (CCN formation. We review both observations and model studies related to this topic, and discuss the potential climatic implications. We conclude that CCN production associated with atmospheric nucleation is both frequent and widespread phenomenon in many types of continental boundary layers, and probably also over a large fraction of the free troposphere. The contribution of nucleation to the global CCN budget spans a relatively large uncertainty range, which, together with our poor understanding of aerosol-cloud interactions, results in major uncertainties in the radiative forcing by atmospheric aerosols. In order to better quantify the role of atmospheric nucleation in CCN formation and Earth System behavior, more information is needed on (i the factors controlling atmospheric CCN production and (ii the properties of both primary and secondary CCN and their interconnections. In future investigations, more emphasis should be put on combining field measurements with regional and large-scale model studies.

A single parameter representation of hygroscopic growth and cloud condensation nucleus activity

Directory of Open Access Journals (Sweden)

M. D. Petters

2007-01-01

Full Text Available We present a method to describe the relationship between particle dry diameter and cloud condensation nuclei (CCN activity using a single hygroscopicity parameter κ. Values of the hygroscopicity parameter are between 0.5 and 1.4 for highly-CCN-active salts such as sodium chloride, between 0.01 and 0.5 for slightly to very hygroscopic organic species, and 0 for nonhygroscopic components. Observations indicate that atmospheric particulate matter is typically characterized by 0.1<κ<0.9. If compositional data are available and if the hygroscopicity parameter of each component is known, a multicomponent hygroscopicity parameter can be computed by weighting component hygroscopicity parameters by their volume fractions in the mixture. In the absence of information on chemical composition, experimental data for complex, multicomponent particles can be fitted to obtain the hygroscopicity parameter. The hygroscopicity parameter can thus also be used to conveniently model the CCN activity of atmospheric particles, including those containing insoluble components. We confirm the applicability of the hygroscopicity parameter and its mixing rule by applying it to published hygroscopic diameter growth factor and CCN-activation data for single- and multi-component particles containing varying amounts of inorganic, organic and surface active compounds. We suggest that κ may be fit to CCN data assuming σs/a=0.072 J m−2 and present a table of κ derived for this value and T=298.15 K. The predicted hygroscopicities for mixtures that contain the surfactant fulvic acid agree within uncertainties with the measured values. It thus appears that this approach is adequate for predicting CCN activity of mixed particles containing surface active materials, but the generality of this assumption requires further verification.

Some properties of the computable cross-norm criterion for separability

International Nuclear Information System (INIS)

Rudolph, Oliver

2003-01-01

The computable cross-norm (CCN) criterion is a powerful analytical and computable separability criterion for bipartite quantum states, which is also known to systematically detect bound entanglement. In certain aspects this criterion complements the well-known Peres positive partial transpose (PPT) criterion. In the present paper we study important analytical properties of the CCN criterion. We show that in contrast to the PPT criterion it is not sufficient in dimension 2x2. In higher dimensions, theorems connecting the fidelity of a quantum state with the CCN criterion are proved. We also analyze the behavior of the CCN criterion under local operations and identify the operations that leave it invariant. It turns out that the CCN criterion is in general not invariant under local operations

Applying super-droplets as a compact representation of warm-rain microphysics for aerosol-cloud-aerosol interactions

Science.gov (United States)

Arabas, S.; Jaruga, A.; Pawlowska, H.; Grabowski, W. W.

2012-12-01

Clouds may influence aerosol characteristics of their environment. The relevant processes include wet deposition (rainout or washout) and cloud condensation nuclei (CCN) recycling through evaporation of cloud droplets and drizzle drops. Recycled CCN physicochemical properties may be altered if the evaporated droplets go through collisional growth or irreversible chemical reactions (e.g. SO2 oxidation). The key challenge of representing these processes in a numerical cloud model stems from the need to track properties of activated CCN throughout the cloud lifecycle. Lack of such "memory" characterises the so-called bulk, multi-moment as well as bin representations of cloud microphysics. In this study we apply the particle-based scheme of Shima et al. 2009. Each modelled particle (aka super-droplet) is a numerical proxy for a multiplicity of real-world CCN, cloud, drizzle or rain particles of the same size, nucleus type,and position. Tracking cloud nucleus properties is an inherent feature of the particle-based frameworks, making them suitable for studying aerosol-cloud-aerosol interactions. The super-droplet scheme is furthermore characterized by linear scalability in the number of computational particles, and no numerical diffusion in the condensational and in the Monte-Carlo type collisional growth schemes. The presentation will focus on processing of aerosol by a drizzling stratocumulus deck. The simulations are carried out using a 2D kinematic framework and a VOCALS experiment inspired set-up (see http://www.rap.ucar.edu/~gthompsn/workshop2012/case1/).

Plume-exit modeling to determine cloud condensation nuclei activity of aerosols from residential biofuel combustion

Science.gov (United States)

Mena, Francisco; Bond, Tami C.; Riemer, Nicole

2017-08-01

Residential biofuel combustion is an important source of aerosols and gases in the atmosphere. The change in cloud characteristics due to biofuel burning aerosols is uncertain, in part, due to the uncertainty in the added number of cloud condensation nuclei (CCN) from biofuel burning. We provide estimates of the CCN activity of biofuel burning aerosols by explicitly modeling plume dynamics (coagulation, condensation, chemical reactions, and dilution) in a young biofuel burning plume from emission until plume exit, defined here as the condition when the plume reaches ambient temperature and specific humidity through entrainment. We found that aerosol-scale dynamics affect CCN activity only during the first few seconds of evolution, after which the CCN efficiency reaches a constant value. Homogenizing factors in a plume are co-emission of semi-volatile organic compounds (SVOCs) or emission at small particle sizes; SVOC co-emission can be the main factor determining plume-exit CCN for hydrophobic or small particles. Coagulation limits emission of CCN to about 1016 per kilogram of fuel. Depending on emission factor, particle size, and composition, some of these particles may not activate at low supersaturation (ssat). Hygroscopic Aitken-mode particles can contribute to CCN through self-coagulation but have a small effect on the CCN activity of accumulation-mode particles, regardless of composition differences. Simple models (monodisperse coagulation and average hygroscopicity) can be used to estimate plume-exit CCN within about 20 % if particles are unimodal and have homogeneous composition, or when particles are emitted in the Aitken mode even if they are not homogeneous. On the other hand, if externally mixed particles are emitted in the accumulation mode without SVOCs, an average hygroscopicity overestimates emitted CCN by up to a factor of 2. This work has identified conditions under which particle populations become more homogeneous during plume processes. This

Learning to Use the Internet and Online Social Media: What Is the Effectiveness of Home-Based Intervention for Youth with Complex Communication Needs?

Science.gov (United States)

Grace, Emma; Raghavendra, Parimala; Newman, Lareen; Wood, Denise; Connell, Tim

2014-01-01

Youth with complex communication needs (CCN) face increased barriers to their social participation due to limited communication abilities and opportunities. Youth today use the internet as a social tool and youth with CCN may also benefit from internet use to increase their social participation. Five youth between the ages of 10-18 with CCN who…

[High-grade pressure sores in frail older high-risk persons. A retrospective postmortem case-control-study].

Science.gov (United States)

Von Renteln-Kruse, W; Krause, T; Anders, J; Kühl, M; Heinemann, A; Püschel, K

2004-04-01

Some old persons at risk do develop, but others, at comparable risk, do not develop high-grade pressure sores. To evaluate potentially different risk factors, we performed a post mortem case-control study in old persons who developed high-grade pressure sores within six months until 14 days before death. Consecutive cases with pressure sores grade >/=3 and potential controls at comparably high risk for pressure sores were examined before cremation. After written informed consent had been obtained by the next relatives, all available nursing and medical records of the deceased were thoroughly evaluated. Cases and controls were matched according to age, gender, immobility, and cachexia.A total of 100 cases with 71 pressure sores grade 3 and 29 pressure sores grade 4 were compared to 100 controls with 27 pressure sores grade pressure sores in frail older high-risk persons. Sedative drug effects and impaired patient compliance with preventive and therapeutic measures may also be associated with the development of high-grade pressure sores in old persons at high risk.

Suggested guidelines for the management of high-profile fatality cases.

Science.gov (United States)

Perper, Joshua A; Juste, Gertrude M; Schueler, Harold E; Motte, Reinhard W; Cina, Stephen J

2008-10-01

The investigation of high-profile fatalities poses special challenges to medical examiners and coroners. Most high-profile cases can be readily recognized early in the course of the investigation. Commonly encountered examples include police-related fatalities or deaths in custody, deaths of celebrities, and mass fatalities or clustered deaths (eg, serial killers). Medical examiner and coroner offices should have policies and procedures in place for adequately handling such cases. A rational approach to these high-profile cases includes activating medical examiner or coroner investigative teams, preplanning before the autopsy, using special autopsy techniques and toxicology procedures, skillful questioning of key witnesses, preparing detailed and comprehensive reports, and planning effective communication with the media. The investigation of the sudden and unexpected death of Anna Nicole Smith, an entertainment personality, is presented as an example of how to address the challenging issues inherent in high-profile fatalities and how to adequately prepare for the forensic investigation of high-profile cases. This article presents a methodical approach to the investigation of high-profile deaths. A comprehensive, preplanned forensic investigation and autopsy (including use of adjunctive studies) following the death of Anna Nicole Smith resulted in the accurate determination of the cause and manner of her death while adequately convincing the public of the objectivity and reliability of the Medical Examiners Office with respect to its conclusions. The forensic investigation of death in high-profile cases can be much more tedious and demanding than the investigation of routine cases. It requires more stringent safekeeping of the body and its evidence, more extensive and sophisticated dissection techniques on occasion, and exhaustive toxicologic analysis to exclude low-probability allegations. Procedures for honest, unbiased, and judicious communication with outside

Effects of condensation nuclei on cloud formation and the development of precipitation in the dry season of the Amazonian region

International Nuclear Information System (INIS)

Martins, Jorge Alberto

2006-01-01

The objective of this work was to study the role of aerosols in modifying clouds and precipitation. This is one of the most difficult aspects in the study of climate changes. Field measurements of cloud condensation nuclei (CCN) and cloud size distributions performed during the Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) campaign revealed distinct characteristics between clean and polluted atmospheric conditions. Measurements were conducted over the southwestern Amazon region during September-October 2002 focusing the transition from dry to wet seasons. During this period, analysis of CCN concentrations in the boundary layer revealed a general decreasing trend from mean values higher than 1200 cm-3 to values lower than 300 cm -3 . The comparison between clean and polluted areas showed CCN concentrations 5 times higher than in polluted areas. These differences were not so strong above the boundary layer. Measurements also showed a diurnal cycle following the biomass burning activity. Cloud droplet size distributions at two regions with extremely different aerosols loading were also analyzed. During biomass-burning conditions, at high concentrations of cloud droplets, the mean diameter and liquid water content increased very little with altitude when compared with unpolluted conditions. A gamma distribution was used to fit the measured droplet spectra and the shape parameter was used as a criterion to define the best choice of spectra representation. According to the found values, narrow gamma distributions optimally fit polluted conditions (shape parameter around 5), while broad distributions are best fits for unpolluted conditions (shape parameter around 2). Based on these results, numerical experiments were carried out using the Brazilian Regional Atmospheric Modeling System (BRAMS) to investigate the effects of CCN concentrations and shape parameters of droplet spectra on the development of precipitation in tropical convective clouds. The

Cloud condensation nuclei in Western Colorado: Observations and model predictions

Science.gov (United States)

Ward, Daniel Stewart

Variations in the warm cloud-active portion of atmospheric aerosols, or cloud condensation nuclei (CCN), have been shown to impact cloud droplet number concentration and subsequently cloud and precipitation processes. This issue carries special significance in western Colorado where a significant portion of the region's water resources is supplied by precipitation from winter season, orographic clouds, which are particularly sensitive to variations in CCN. Temporal and spatial variations in CCN in western Colorado were investigated using a combination of observations and a new method for modeling CCN. As part of the Inhibition of Snowfall by Pollution Aerosols (ISPA-III) field campaign, total particle and CCN number concentration were measured for a 24-day period in Mesa Verde National Park, climatologically upwind of the San Juan Mountains. These data were combined with CCN observations from Storm Peak Lab (SPL) in northwestern Colorado and from the King Air platform, flying north to south along the Western Slope. Altogether, the sampled aerosols were characteristic of a rural continental environment and the cloud-active portion varied slowly in time, and little in space. Estimates of the is hygroscopicity parameter indicated consistently low aerosol hygroscopicity typical of organic aerosol species. The modeling approach included the addition of prognostic CCN to the Regional Atmospheric Modeling System (RAMS). The RAMS droplet activation scheme was altered using parcel model simulations to include variations in aerosol hygroscopicity, represented by K. Analysis of the parcel model output and a supplemental sensitivity study showed that model CCN will be sensitive to changes in aerosol hygroscopicity, but only for conditions of low supersaturation or small particle sizes. Aerosol number, size distribution median radius, and hygroscopicity (represented by the K parameter) in RAMS were constrained by nudging to forecasts of these quantities from the Weather

Connective-Tissue Growth Factor (CTGF/CCN2 Induces Astrogenesis and Fibronectin Expression of Embryonic Neural Cells In Vitro.

Directory of Open Access Journals (Sweden)

Fabio A Mendes

Full Text Available Connective-tissue growth factor (CTGF is a modular secreted protein implicated in multiple cellular events such as chondrogenesis, skeletogenesis, angiogenesis and wound healing. CTGF contains four different structural modules. This modular organization is characteristic of members of the CCN family. The acronym was derived from the first three members discovered, cysteine-rich 61 (CYR61, CTGF and nephroblastoma overexpressed (NOV. CTGF is implicated as a mediator of important cell processes such as adhesion, migration, proliferation and differentiation. Extensive data have shown that CTGF interacts particularly with the TGFβ, WNT and MAPK signaling pathways. The capacity of CTGF to interact with different growth factors lends it an important role during early and late development, especially in the anterior region of the embryo. ctgf knockout mice have several cranio-facial defects, and the skeletal system is also greatly affected due to an impairment of the vascular-system development during chondrogenesis. This study, for the first time, indicated that CTGF is a potent inductor of gliogenesis during development. Our results showed that in vitro addition of recombinant CTGF protein to an embryonic mouse neural precursor cell culture increased the number of GFAP- and GFAP/Nestin-positive cells. Surprisingly, CTGF also increased the number of Sox2-positive cells. Moreover, this induction seemed not to involve cell proliferation. In addition, exogenous CTGF activated p44/42 but not p38 or JNK MAPK signaling, and increased the expression and deposition of the fibronectin extracellular matrix protein. Finally, CTGF was also able to induce GFAP as well as Nestin expression in a human malignant glioma stem cell line, suggesting a possible role in the differentiation process of gliomas. These results implicate ctgf as a key gene for astrogenesis during development, and suggest that its mechanism may involve activation of p44/42 MAPK signaling

Environmental conditions regulate the impact of plants on cloud formation.

Science.gov (United States)

Zhao, D F; Buchholz, A; Tillmann, R; Kleist, E; Wu, C; Rubach, F; Kiendler-Scharr, A; Rudich, Y; Wildt, J; Mentel, Th F

2017-02-20

The terrestrial vegetation emits large amounts of volatile organic compounds (VOC) into the atmosphere, which on oxidation produce secondary organic aerosol (SOA). By acting as cloud condensation nuclei (CCN), SOA influences cloud formation and climate. In a warming climate, changes in environmental factors can cause stresses to plants, inducing changes of the emitted VOC. These can modify particle size and composition. Here we report how induced emissions eventually affect CCN activity of SOA, a key parameter in cloud formation. For boreal forest tree species, insect infestation by aphids causes additional VOC emissions which modifies SOA composition thus hygroscopicity and CCN activity. Moderate heat increases the total amount of constitutive VOC, which has a minor effect on hygroscopicity, but affects CCN activity by increasing the particles' size. The coupling of plant stresses, VOC composition and CCN activity points to an important impact of induced plant emissions on cloud formation and climate.

Investigation of cloud condensation nuclei properties and droplet growth kinetics of the water-soluble aerosol fraction in Mexico City

Science.gov (United States)

Padró, Luz T.; Tkacik, Daniel; Lathem, Terry; Hennigan, Chris J.; Sullivan, Amy P.; Weber, Rodney J.; Huey, L. Greg; Nenes, Athanasios

2010-05-01

We present hygroscopic and cloud condensation nuclei (CCN) relevant properties of the water-soluble fraction of Mexico City aerosol collected upon filters during the 2006 Megacity Initiative: Local and Global Research Observations (MILAGRO) campaign. Application of κ-Köhler theory to the observed CCN activity gave a fairly constant hygroscopicity parameter (κ = 0.28 ± 0.06) regardless of location and organic fraction. Köhler theory analysis was used to understand this invariance by separating the molar volume and surfactant contributions to the CCN activity. Organics were found to depress surface tension (10-15%) from that of pure water. Daytime samples exhibited lower molar mass (˜200 amu) and surface tension depression than nighttime samples (˜400 amu); this is consistent with fresh hygroscopic secondary organic aerosol (SOA) condensing onto particles during peak photochemical hours, subsequently aging during nighttime periods of high relative humidity. Changes in surface tension partially compensate for shifts in average molar volume to give the constant hygroscopicity observed, which implies the amount (volume fraction) of soluble material in the parent aerosol is the key composition parameter required for CCN predictions. This finding, if applicable elsewhere, may explain why CCN predictions are often found to be insensitive to assumptions of chemical composition and provides a very simple way to parameterize organic hygroscopicity in atmospheric models (i.e., κorg = 0.28ɛWSOC). Special care should be given, however, to surface tension depression from organic surfactants, as its nonlinear dependence with organic fraction may introduce biases in observed (and predicted) hygroscopicity. Finally, threshold droplet growth analysis suggests the water-soluble organics do not affect activation kinetics.

Biomass Smoke Influences on Deep Convection during the 2011 Midlatitude Continental Convective Clouds Experiment (MC3E)

Science.gov (United States)

Dong, X.; Logan, T.; Xi, B.

2015-12-01

Three deep convective cloud cases were selected during the 2011 Mid-Latitude Continental Convective Clouds Experiment (MC3E). Although biomass burning smoke advected from Mexico and Central America was the dominant source of cloud condensation nuclei (CCN) for deep convective cloud formation, the 11 May, 20 May, and 23 May cases exhibited different convective characteristics. The convection in the 11 May and 23 May cases formed in smoke laden environments in the presence of convective available potential energy (CAPE) values exceeding 1000 m2 s-2 and 3000 m2 s-2 along with low-level (0-1 km) shear of 10.3 m s-1 and 5.1 m s-1, respectively. The 11 May case had linear convection while the 23 May case featured discrete supercells. The 20 May case featured elevated linear convection that formed in a more moist environment with cleaner aerosol conditions, weak CAPE (9 km) suggesting a warm rain suppression mechanism caused by a combination of strong aerosol loading, large CAPE, and weak low-level wind shear. The observed results for the 20 May and 23 May cases agree well with recent modeling studies that simulated the convection and precipitation in these cases. Furthermore, the modeling of the 11 May case is suggested since the abundant amount of smoke CCN did not greatly enhance the overall precipitation amount and could be a possible aerosol-induced precipitation suppression case.

Success Despite Socioeconomics: A Case Study of a High-Achieving, High-Poverty School

Science.gov (United States)

Tilley, Thomas Brent; Smith, Samuel J.; Claxton, Russell L.

2012-01-01

This case study of a high-achieving, high-poverty school describes the school's leadership, culture, and programs that contributed to its success. Data were collected from two surveys (the School Culture Survey and the Vanderbilt Assessment of Leadership in Education), observations at the school site, and interviews with school personnel. The…

High dimensional classifiers in the imbalanced case

DEFF Research Database (Denmark)

Bak, Britta Anker; Jensen, Jens Ledet

We consider the binary classification problem in the imbalanced case where the number of samples from the two groups differ. The classification problem is considered in the high dimensional case where the number of variables is much larger than the number of samples, and where the imbalance leads...... to a bias in the classification. A theoretical analysis of the independence classifier reveals the origin of the bias and based on this we suggest two new classifiers that can handle any imbalance ratio. The analytical results are supplemented by a simulation study, where the suggested classifiers in some...

High Concentrations of Measles Neutralizing Antibodies and High-Avidity Measles IgG Accurately Identify Measles Reinfection Cases

Science.gov (United States)

Rota, Jennifer S.; Hickman, Carole J.; Mercader, Sara; Redd, Susan; McNall, Rebecca J.; Williams, Nobia; McGrew, Marcia; Walls, M. Laura; Rota, Paul A.; Bellini, William J.

2016-01-01

In the United States, approximately 9% of the measles cases reported from 2012 to 2014 occurred in vaccinated individuals. Laboratory confirmation of measles in vaccinated individuals is challenging since IgM assays can give inconclusive results. Although a positive reverse transcription (RT)-PCR assay result from an appropriately timed specimen can provide confirmation, negative results may not rule out a highly suspicious case. Detection of high-avidity measles IgG in serum samples provides laboratory evidence of a past immunologic response to measles from natural infection or immunization. High concentrations of measles neutralizing antibody have been observed by plaque reduction neutralization (PRN) assays among confirmed measles cases with high-avidity IgG, referred to here as reinfection cases (RICs). In this study, we evaluated the utility of measuring levels of measles neutralizing antibody to distinguish RICs from noncases by receiver operating characteristic curve analysis. Single and paired serum samples with high-avidity measles IgG from suspected measles cases submitted to the CDC for routine surveillance were used for the analysis. The RICs were confirmed by a 4-fold rise in PRN titer or by RT-quantitative PCR (RT-qPCR) assay, while the noncases were negative by both assays. Discrimination accuracy was high with serum samples collected ≥3 days after rash onset (area under the curve, 0.953; 95% confidence interval [CI], 0.854 to 0.993). Measles neutralizing antibody concentrations of ≥40,000 mIU/ml identified RICs with 90% sensitivity (95% CI, 74 to 98%) and 100% specificity (95% CI, 82 to 100%). Therefore, when serological or RT-qPCR results are unavailable or inconclusive, suspected measles cases with high-avidity measles IgG can be confirmed as RICs by measles neutralizing antibody concentrations of ≥40,000 mIU/ml. PMID:27335386

Perspectives of a mobile application for people with communication disabilities in the community.

Science.gov (United States)

Crook, Alice; Kenny, Julie; Johnson, Hilary; Davidson, Bronwyn

2017-02-01

Purpose To determine the perceptions of people with complex communication needs (CCN) and business staff regarding the uses and functionality of a mobile application to aid communication access. Method A qualitative study using thematic analysis of transcripts and field notes from focus groups and interviews of 19 people with CCN and nine business staff. Results Four themes and 10 subthemes were drawn from the data. Themes highlighted the desire for: increased communication strategies to support customer interactions, increased access to information, functionality of a mobile application to increase its utility, and preferred technical and visual features of mobile applications. Conclusion People with CCN and business staff perceived a mobile application as a useful tool to aid communication access. This research highlighted the importance of facilitating strategies to communicative interactions and information in the community as the fundamental goal of a mobile application developed to support communication access. Implications for Rehabilitation Mobile applications are widely accepted and used in modern customer service industries and have been identified as tools to increase communication access for people with complex communication needs (CCN). People with CCN identified accessibility, presentation, and customisation as important features of mobile applications for communication access. The diversity of user preferences and needs, and the rapid development of new technologies limit the applicability of a single design for mobile applications for people with CCN. People with CCN should be involved in application design and development. A mobile application for communication access would support customer-business interactions as well as enable more accessible information sharing about disability needs and services.

Case Studies of Leading Edge Small Urban High Schools. Relevance Strategic Designs: 8. High Tech High School

Science.gov (United States)

Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

2008-01-01

This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

The effects of aerosols on precipitation and dimensions of subtropical clouds: a sensitivity study using a numerical cloud model

Directory of Open Access Journals (Sweden)

A. Teller

2006-01-01

Full Text Available Numerical experiments were carried out using the Tel-Aviv University 2-D cloud model to investigate the effects of increased concentrations of Cloud Condensation Nuclei (CCN, giant CCN (GCCN and Ice Nuclei (IN on the development of precipitation and cloud structure in mixed-phase sub-tropical convective clouds. In order to differentiate between the contribution of the aerosols and the meteorology, all simulations were conducted with the same meteorological conditions. The results show that under the same meteorological conditions, polluted clouds (with high CCN concentrations produce less precipitation than clean clouds (with low CCN concentrations, the initiation of precipitation is delayed and the lifetimes of the clouds are longer. GCCN enhance the total precipitation on the ground in polluted clouds but they have no noticeable effect on cleaner clouds. The increased rainfall due to GCCN is mainly a result of the increased graupel mass in the cloud, but it only partially offsets the decrease in rainfall due to pollution (increased CCN. The addition of more effective IN, such as mineral dust particles, reduces the total amount of precipitation on the ground. This reduction is more pronounced in clean clouds than in polluted ones. Polluted clouds reach higher altitudes and are wider than clean clouds and both produce wider clouds (anvils when more IN are introduced. Since under the same vertical sounding the polluted clouds produce less rain, more water vapor is left aloft after the rain stops. In our simulations about 3.5 times more water evaporates after the rain stops from the polluted cloud as compared to the clean cloud. The implication is that much more water vapor is transported from lower levels to the mid troposphere under polluted conditions, something that should be considered in climate models.

Global cloud condensation nuclei influenced by carbonaceous combustion aerosol

Directory of Open Access Journals (Sweden)

D. V. Spracklen

2011-09-01

Full Text Available Black carbon in carbonaceous combustion aerosol warms the climate by absorbing solar radiation, meaning reductions in black carbon emissions are often perceived as an attractive global warming mitigation option. However, carbonaceous combustion aerosol can also act as cloud condensation nuclei (CCN so they also cool the climate by increasing cloud albedo. The net radiative effect of carbonaceous combustion aerosol is uncertain because their contribution to CCN has not been evaluated on the global scale. By combining extensive observations of CCN concentrations with the GLOMAP global aerosol model, we find that the model is biased low (normalised mean bias = −77 % unless carbonaceous combustion aerosol act as CCN. We show that carbonaceous combustion aerosol accounts for more than half (52–64 % of global CCN with the range due to uncertainty in the emitted size distribution of carbonaceous combustion particles. The model predicts that wildfire and pollution (fossil fuel and biofuel carbonaceous combustion aerosol causes a global mean cloud albedo aerosol indirect effect of −0.34 W m⁻², with stronger cooling if we assume smaller particle emission size. We calculate that carbonaceous combustion aerosol from pollution sources cause a global mean aerosol indirect effect of −0.23 W m⁻². The small size of carbonaceous combustion particles from fossil fuel sources means that whilst pollution sources account for only one-third of the emitted mass they cause two-thirds of the cloud albedo aerosol indirect effect that is due to carbonaceous combustion aerosol. This cooling effect must be accounted for, along with other cloud effects not studied here, to ensure that black carbon emissions controls that reduce the high number concentrations of fossil fuel particles have the desired net effect on climate.

Forensic entomology of high-rise buildings in Malaysia: Three case reports.

Science.gov (United States)

Syamsa, R A; Omar, B; Zuha, R M; Faridah, M N; Swarhib, M S; Hidayatulfathi, O; Shahrom, A W

2015-06-01

The distributions of flies are not only confined to ground level but can also be at higher altitudes. Here, we report three forensic cases involving dipterans in high-rise buildings in Kuala Lumpur, Malaysia. Case 1 involved a corpse of adult female found at the top floor of a fifteen-story apartment. Case 2 dealt with a body of a 75-year-old female discovered in a bedroom on the eleventh floor of an eighteen-story building, while Case 3 was a 52-year-old male found in his fifth floor shop house. Interestingly, entomological analysis revealed that all corpses were infested with similar Dipterans: Megaselia scalaris (Loew) (Diptera: Phoridae), Synthesiomyia nudiseta (Wulp) (Diptera: Muscidae) and sarcophagid (Diptera: Sarcophagidae). The first two species were commonly associated with corpses found indoors at ground level. We noted the additional occurrence of blowflies Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae) and Chrysomya rufifacies Macquart (Diptera: Calliphoridae) larvae in Case 2 and Case 3, respectively. Findings from this study are significant as they demonstrate that certain groups of fly can locate dead bodies even in high-rise buildings. Forensic entomofauna research on corpses found at high elevation is scarce and our study has highlighted the peculiarity of the fly species involved in Malaysia.

Sensitivity of the Palaeocene-Eocene Thermal Maximum climate to cloud properties.

Science.gov (United States)

Kiehl, Jeffrey T; Shields, Christine A

2013-10-28

The Palaeocene-Eocene Thermal Maximum (PETM) was a significant global warming event in the Earth's history (approx. 55 Ma). The cause for this warming event has been linked to increases in greenhouse gases, specifically carbon dioxide and methane. This rapid warming took place in the presence of the existing Early Eocene warm climate. Given that projected business-as-usual levels of atmospheric carbon dioxide reach concentrations of 800-1100 ppmv by 2100, it is of interest to study past climates where atmospheric carbon dioxide was higher than present. This is especially the case given the difficulty of climate models in simulating past warm climates. This study explores the sensitivity of the simulated pre-PETM and PETM periods to change in cloud condensation nuclei (CCN) and microphysical properties of liquid water clouds. Assuming lower levels of CCN for both of these periods leads to significant warming, especially at high latitudes. The study indicates that past differences in cloud properties may be an important factor in accurately simulating past warm climates. Importantly, additional shortwave warming from such a mechanism would imply lower required atmospheric CO2 concentrations for simulated surface temperatures to be in reasonable agreement with proxy data for the Eocene.

Record High US Measles Cases: Patient Vaccination, Clinical Assessment and Management

Centers for Disease Control (CDC) Podcasts

This podcast is an overview of the Clinician Outreach and Communication Activity (COCA) Call: Record High US Measles Cases: Patient Vaccination, Clinical Assessment and Management. In May 2014, the United States recorded the largest number of reported measles cases since 1994 and the number continues to rise. Most cases reported have been acquired in the U.S. and are associated with importations from countries where measles is still common. This highly contagious, acute viral illness spreads quickly in unvaccinated populations once reaching the U.S. The recent measles outbreaks highlight the importance of maintaining high vaccination coverage in the U.S. and ensuring age-appropriate vaccination for international travelers. During this COCA call, clinicians will learn the status of measles in the U.S. and CDC vaccination recommendations and guidelines for patient assessment and management.

Cereal cyst nematode resistance conferred by the Cre7 gene from Aegilops triuncialis and its relationship with Cre genes from Australian wheat cultivars

OpenAIRE

Montes, Maria Jesus; Andrés, María Fe; Sin, E.; Lopez Braña, Isidoro; Martín-Sánchez, J.A.; Romero, M.D.; Delibes Castro, Angeles

2008-01-01

Cereal cyst nematode (CCN; Heterodera avenae Woll.) is a root pathogen of cereal crops that can cause severe yield losses in wheat (Triticum aestivum). Differential host–nematode interactions occur in wheat cultivars carrying different CCN resistance (Cre) genes. The objective of this study was to determine the CCN resistance conferred by the Cre7 gene from Aegilops triuncialis in a 42-chromosome introgression line and to assess the effects of the Cre1, Cre3, Cre4, and Cre8 genes present in A...

High-resolution CT of temporal bone trauma: review of 38 cases

International Nuclear Information System (INIS)

Hiroual, M.R.; Zougarhi, A.; Cherif Idrissi El Ganouni, N.; Essadki, O.; Ousehal, A.; Tijani Adil, O.; Maliki, O.; Aderdour, L.; Raji, A.

2010-01-01

Purpose Temporal bone trauma is frequent but difficult to assess due to the diversity of clinical presentations and complex anatomy. We have sought to assess the different types of fractures and complications on high-resolution CT. Materials and methods Descriptive retrospective study over a 24 month period performed in the ENT radiology section of the Mohammed 6 university medical center in Marrakech. A total of 38 cases of temporal bone trauma were reviewed. All patients underwent ENT evaluation and high-resolution CT of the temporal bone using 1 mm axial and coronal sections. Results Mean patient age was 33 years (range: 14-55 years) with male predominance (sex ratio: 36/2). Clinical symptoms were mainly otorrhagia and conductive hearing loss. Oblique extra-labyrinthine fractures were most frequent. Two cases of pneumo-labyrinth were noted. Management was conservative in most cases with deafness in 3 cases. Conclusion High-resolution CT of the temporal bone provides accurate depiction of lesions explaining the clinical symptoms and helps guide management. MRI is complimentary to further assess the labyrinth and VII-VIII nerve complex. (author)

CHASER: An Innovative Satellite Mission Concept to Measure the Effects of Aerosols on Clouds and Climate

Science.gov (United States)

Renno, N.; Williams, E.; Rosenfeld, D.; Fischer, D.; Fischer, J.; Kremic, T.; Agrawal, A.; Andreae, M.; Bierbaum, R.; Blakeslee, R.; Boerner, A.; Bowles, N.; Christian, H.; Dunion, J.; Horvath, A.; Huang, X.; Khain, A.; Kinne, S.; Lemos, M.-C.; Penner, J.

2012-04-01

The formation of cloud droplets on aerosol particles, technically known as the activation of cloud condensation nuclei (CCN), is the fundamental process driving the interactions of aerosols with clouds and precipitation. Knowledge of these interactions is foundational to our understanding of weather and climate. The Intergovernmental Panel on Climate Change (IPCC) and the Decadal Survey (NRC 2007) indicate that the uncertainty in how clouds adjust to aerosol perturbations dominates the uncertainty in the overall quantification of the radiative forcing attributable to human activities. The Clouds, Hazards, and Aerosols Survey for Earth Researchers (CHASER) mission concept responds to the IPCC and Decadal Survey concerns by studying the activation of CCN and their interactions with clouds and storms. CHASER proposes to revolutionize our understanding of the interactions of aerosols with clouds by making the first global measurements of the fundamental physical entity linking them: activated cloud condensation nuclei. The CHASER mission was conceptualized to measure all quantities necessary for determining the interactions of aerosols with clouds and storms. Measurements by current satellites allow the determination of crude profiles of cloud particle size but not of the activated CCN that seed them. CHASER uses a new technique (Freud et al. 2011; Rosenfeld et al. 2012) and high-heritage instruments to produce the first global maps of activated CCN and the properties of the clouds associated with them. CHASER measures the CCN concentration and cloud thermodynamic forcing simultaneously, allowing their effects to be distinguished. Changes in the behavior of a group of weather systems in which only one of the quantities varies (a partial derivative of the intensity with the desirable quantity) allow the determination of each effect statistically. The high uncertainties of current climate predictions limit their much-needed use in decision-making. CHASER mitigates this

Droplet activation properties of organic aerosols observed at an urban site during CalNex-LA

Energy Technology Data Exchange (ETDEWEB)

Mei, Fan [Brookhaven National Laboratory, Upton New York USA; Pacific Northwest National Laboratory, Richland Washington USA; Hayes, Patrick L. [Cooperative Institute for Research in Environmental Sciences, Boulder Colorado USA; Department of Chemistry and Biochemistry, University of Colorado, Boulder Colorado USA; Ortega, Amber [Cooperative Institute for Research in Environmental Sciences, Boulder Colorado USA; Department of Chemistry and Biochemistry, University of Colorado, Boulder Colorado USA; Taylor, Jonathan W. [School of Earth, Atmospheric and Environmental Sciences, University of Manchester, Manchester UK; Allan, James D. [School of Earth, Atmospheric and Environmental Sciences, University of Manchester, Manchester UK; National Centre for Atmospheric Science, University of Manchester, Manchester UK; Gilman, Jessica [NOAA Earth System Research Laboratory, Boulder Colorado USA; Kuster, William [NOAA Earth System Research Laboratory, Boulder Colorado USA; de Gouw, Joost [NOAA Earth System Research Laboratory, Boulder Colorado USA; Jimenez, Jose L. [Cooperative Institute for Research in Environmental Sciences, Boulder Colorado USA; Department of Chemistry and Biochemistry, University of Colorado, Boulder Colorado USA; Wang, Jian [Brookhaven National Laboratory, Upton New York USA

2013-04-11

Size-resolved cloud condensation nuclei (CCN) spectra and aerosol chemical composition were characterized at an urban supersite in Pasadena, California, from 15 May to 4 June 2010, during the CalNex campaign. The derived hygroscopicity (κ_CCN) of CCN-active particles with diameter between 97 and 165 nm ranged from 0.05 to 0.4. Diurnal variation showed a slight decrease of κ_CCN from 8:00 to 16:00 (from 0.24 to 0.20), which is attributed to increasing organics volume fraction resulted from secondary organic aerosol (SOA) formation. The derived hygroscopicity distribution and maximum activated fraction of the size selected particles were examined as functions of photochemical age. The result indicates that condensation of secondary species (e.g., SOA and sulfate) quickly converted hydrophobic particles to hydrophilic ones, and during daytime, nearly every particle became a CCN at ~0.4% in just a few hours. Based on κ_CCN and aerosol chemical composition, the organic hygroscopicity (κ_org) was derived, and ranged from 0.05 to 0.23 with an average value of 0.13, consistent with the results from earlier studies. The derived κ_org generally increased with the organic oxidation level, and most of the variation in κ_org could be explained by the variation of the organic O : C atomic ratio alone. The least squares fit of the data yielded κorg = (0.83 ± 0.06) × (O:C) + (-0.19 ± 0.02). Compared to previous results based on CCN measurements of laboratory generated aerosols, κ_org derived from measurements during the CalNex campaign exhibited stronger increase with O : C atomic ratio and therefore substantially higher values for organics with average O : C greater than 0.5.

Increased and correlated expression of connective tissue growth factor and transforming growth factor beta 1 in surgically removed periodontal tissues with chronic periodontitis.

Science.gov (United States)

Mize, T W; Sundararaj, K P; Leite, R S; Huang, Y

2015-06-01

Both gingival tissue destruction and regeneration are associated with chronic periodontitis, although the former overwhelms the latter. Studies have shown that transforming growth factor beta 1 (TGF-β1), a growth factor largely involved in tissue regeneration and remodeling, is upregulated in chronic periodontitis. However, the gingival expression of connective tissue growth factor (CTGF or CCN2), a TGF-β1-upregulated gene, in patients with periodontitis remains undetermined. Although both CTGF/CCN2 and TGF-b1 increase the production of extracellular matrix, they have many different biological functions. Therefore, it is important to delineate the impact of periodontitis on gingival CTGF/CCN2 expression. Periodontal tissue specimens were collected from seven individuals without periodontitis (group 1) and from 14 with periodontitis (group 2). The expression of CTGF and TGFβ1 mRNAs were quantified using real-time PCR. Analysis using the nonparametric Mann-Whitney U-test showed that the levels of expression of both CTGF/CCN2 and TGFβ1 mRNAs were significantly increased in individuals with periodontitis compared with individuals without periodontitis. Furthermore, analysis using a nonparametric correlation (Spearman r) test showed a positive correlation between TGFβ1 and CTGF/CCN2 mRNAs. The gingival expression levels of CTGF/CCN2 and TGFβ1 mRNAs in individuals with periodontitis are upregulated and correlated. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Role of Water Vapor Content in the Effects of Aerosol on the Electrification of Thunderstorms: A Numerical Study

Directory of Open Access Journals (Sweden)

Pengguo Zhao

2016-10-01

Full Text Available We explored the role of the water vapor content below the freezing level in the response of idealized supercell storm electrical processes to increased concentrations of cloud condensation nuclei (CCN. Using the Weather Research and Forecasting model coupled with parameterizations electrification and discharging, we performed 30 simulations by varying both the CCN concentration and water vapor content below the freezing level. The sensitivity simulations showed a distinct response to increased concentrations of CCN, depending on the water vapor content below the freezing level. Enhancing CCN concentrations increased electrification processes of thunderstorms and produced a new negative charge region above the main positive charge center when there were ample amounts of water vapor below the freezing level. Conversely, there were weak effects on electrification and the charge structure in numerical experiments initialized with lower water vapor content below the freezing level.

Multimodal Behavior Therapy: Case Study of a High School Student.

Science.gov (United States)

Seligman, Linda

1981-01-01

A case study of a high school student concerned with weight problems illustrates multimodal behavior therapy and its use in a high school setting. Multimodal therapy allows the school counselor to maximize referral sources while emphasizing growth and actualization. (JAC)

Examination of the potential impacts of dust and pollution aerosol acting as cloud nucleating aerosol on water resources in the Colorado River Basin

Science.gov (United States)

Jha, Vandana

In this study we examine the cumulative effect of dust acting as cloud nucleating aerosol (cloud condensation nuclei (CCN), giant cloud condensation nuclei (GCCN), and ice nuclei (IN)) along with anthropogenic aerosol pollution acting primarily as CCN, over the entire Colorado Rocky Mountains from the months of October to April in the year 2004-2005; the snow year. This ˜6.5 months analysis provides a range of snowfall totals and variability in dust and anthropogenic aerosol pollution. The specific objectives of this research is to quantify the impacts of both dust and pollution aerosols on wintertime precipitation in the Colorado Mountains using the Regional Atmospheric Modeling System (RAMS). In general, dust enhances precipitation primarily by acting as IN, while aerosol pollution reduces water resources in the CRB via the so-called "spill-over" effect, by enhancing cloud droplet concentrations and reducing riming rates. Dust is more episodic and aerosol pollution is more pervasive throughout the winter season. Combined response to dust and aerosol pollution is a net reduction of water resources in the CRB. The question is by how much are those water resources affected? Our best estimate is that total winter-season precipitation loss for for the CRB the 2004-2005 winter season due to the combined influence of aerosol pollution and dust is 5,380,00 acre-feet of water. Sensitivity studies for different cases have also been run for the specific cases in 2004-2005 winter season to analyze the impact of changing dust and aerosol ratios on precipitation in the Colorado River Basin. The dust is varied from 3 to 10 times in the experiments and the response is found to be non monotonic and depends on various environmental factors. The sensitivity studies show that adding dust in a wet system increases precipitation when IN affects are dominant. For a relatively dry system high concentrations of dust can result in over-seeding the clouds and reductions in precipitation

Water uptake by biomass burning aerosol at sub- and supersaturated conditions: closure studies and implications for the role of organics

Directory of Open Access Journals (Sweden)

U. Dusek

2011-09-01

Full Text Available We investigate the CCN activity of freshly emitted biomass burning particles and their hygroscopic growth at a relative humidity (RH of 85%. The particles were produced in the Mainz combustion laboratory by controlled burning of various wood types. The water uptake at sub- and supersaturations is parameterized by the hygroscopicity parameter, κ (c.f. Petters and Kreidenweis, 2007. For the wood burns, κ is low, generally around 0.06. The main emphasis of this study is a comparison of κ derived from measurements at sub- and supersaturated conditions (κ_G and κ_CCN, in order to see whether the water uptake at 85% RH can predict the CCN properties of the biomass burning particles. Differences in κ_Gand κ_CCN can arise through solution non-idealities, the presence of slightly soluble or surface active compounds, or non-spherical particle shape. We find that κ_G and κ_CCN agree within experimental uncertainties (of around 30% for particle sizes of 100 and 150 nm; only for 50 nm particles is κ_CCN larger than κ_G by a factor of 2. The magnitude of this difference and its dependence on particle size is consistent with the presence of surface active organic compounds. These compounds mainly facilitate the CCN activation of small particles, which form the most concentrated solution droplets at the point of activation. The 50 nm particles, however, are only activated at supersaturations higher than 1% and are therefore of minor importance as CCN in ambient clouds. By comparison with the actual chemical composition of the biomass burning particles, we estimate that the hygroscopicity of the water-soluble organic carbon (WSOC fraction can be represented by a κ_WSOC value of approximately 0.2. The effective hygroscopicity of a typical wood burning particle can therefore be represented by a linear mixture of an inorganic component with κ ≅ 0.6, a WSOC

O desafio da convivência: assessoria de diversidade e apoio aos cotistas (2004-2008 El desafío de la convivencia: asesoría de diversidad y apoyo a los cotizantes (2004-2008 The challenge of conviviality: advisory For diversity and support to quota holders (2004-2008

Directory of Open Access Journals (Sweden)

Jaqueline Gomes de Jesus

2013-01-01

Full Text Available Em 2003, a Universidade de Brasília adotou uma política de ações afirmativas para pessoas negras, o Sistema de Cotas para Negros. Em 2004, foi criada a Assessoria de Diversidade e Apoio aos Cotistas - ADAC. Ante à demanda do movimento social por uma sala de apoio aos estudantes, desenvolveu-se o Centro de Convivência Negra - CCN, espaço aberto a toda a comunidade acadêmica. O presente artigo apresenta a experiência da ADAC até 2008 e analisa os desafios da convivência entre estudantes cotistas e o espaço acadêmico a partir de pesquisa qualitativa sobre percepções, sentimentos e expectativas acerca do CCN, na forma de questionários com uma pergunta de evocação ao CCN, aplicados a 35 estudantes universitários oriundos do Sistema de Cotas para Negros frequentadores do CCN. Os dados de evocação foram analisados utilizando-se o software Evoc. Os resultados indicam que o CCN, no período analisado, era reconhecido por seus usuários como um espaço de acolhimento ante a uma organização acadêmica heterogênea, marcada por preconceitos. São discutidas as limitações e as possibilidades de intervenção a partir do uso do CCN, e uma agenda propositiva para a ADAC, com foco na gestão da diversidade.En 2003, la Universidad de Brasilia adoptó una política de acciones afirmativas para personas negras, el Sistema de Cotas para Negros. En 2004, fue creada la Asesoría de Diversidad y Apoyo a los Cotizantes - ADAC. Ante la demanda del movimiento social por una sala de apoyo a los estudiantes, se desarrolló el Centro de Convivencia Negra - CCN, espacio abierto a toda la comunidad académica. El presente artículo presenta la experiencia de la ADAC hasta 2008 y analiza los desafíos de la convivencia entre estudiantes cotizantes y el espacio académico a partir de una investigación cualitativa sobre percepciones, sentimientos y expectativas acerca del CCN, en la forma de cuestionarios con una pregunta de evocación al CCN, aplicados

Laboratory study of the effect of oxalic acid on the cloud condensation nuclei activity of mineral dust aerosol

Science.gov (United States)

Gierlus, Kelly M.; Laskina, Olga; Abernathy, Tricia L.; Grassian, Vicki H.

2012-01-01

Dicarboxylic acids, which make up a significant portion of the atmospheric organic aerosol, are emitted directly through biomass burning as well as produced through the oxidation of volatile organic compounds. Oxalic acid, the most abundant of the dicarboxylic acids, has been shown by recent field studies to be present in mineral dust aerosol particles. The presence of these internally mixed organic compounds can alter the water absorption and cloud condensation nuclei (CCN) abilities of mineral particles in the Earth's atmosphere. The University of Iowa's Multi-Analysis Aerosol Reactor System ( MAARS) was used to measure the CCN activity of internally mixed particles that were generated from a mixture of either calcite or polystyrene latex spheres (PSLs) in an aqueous solution of oxalic acid. Although PSL is not a mineral dust component, it is used here as a non-reactive, insoluble particle. CCN measurements indicate that the internally mixed oxalate/calcite particles showed nearly identical CCN activity compared to the original calcite particles whereas oxalic acid/PSL internally mixed particles showed much greater CCN activity compared to PSL particles alone. This difference is due to the reaction of calcite with oxalic acid, which produces a relatively insoluble calcium oxalate coating on the particle surface and not a soluble coating as it does on the PSL particle. Our results suggest that atmospheric processing of mineral dust aerosol through heterogeneous processes will likely depend on the mineralogy and the specific chemistry involved. Increase in the CCN activity by incorporation of oxalic acid are only expected for unreactive insoluble dust particles that form a soluble coating.

Surfactants from the gas phase may promote cloud droplet formation.

Science.gov (United States)

Sareen, Neha; Schwier, Allison N; Lathem, Terry L; Nenes, Athanasios; McNeill, V Faye

2013-02-19

Clouds, a key component of the climate system, form when water vapor condenses upon atmospheric particulates termed cloud condensation nuclei (CCN). Variations in CCN concentrations can profoundly impact cloud properties, with important effects on local and global climate. Organic matter constitutes a significant fraction of tropospheric aerosol mass, and can influence CCN activity by depressing surface tension, contributing solute, and influencing droplet activation kinetics by forming a barrier to water uptake. We present direct evidence that two ubiquitous atmospheric trace gases, methylglyoxal (MG) and acetaldehyde, known to be surface-active, can enhance aerosol CCN activity upon uptake. This effect is demonstrated by exposing acidified ammonium sulfate particles to 250 parts per billion (ppb) or 8 ppb gas-phase MG and/or acetaldehyde in an aerosol reaction chamber for up to 5 h. For the more atmospherically relevant experiments, i.e., the 8-ppb organic precursor concentrations, significant enhancements in CCN activity, up to 7.5% reduction in critical dry diameter for activation, are observed over a timescale of hours, without any detectable limitation in activation kinetics. This reduction in critical diameter enhances the apparent particle hygroscopicity up to 26%, which for ambient aerosol would lead to cloud droplet number concentration increases of 8-10% on average. The observed enhancements exceed what would be expected based on Köhler theory and bulk properties. Therefore, the effect may be attributed to the adsorption of MG and acetaldehyde to the gas-aerosol interface, leading to surface tension depression of the aerosol. We conclude that gas-phase surfactants may enhance CCN activity in the atmosphere.

[Transcultural self-efficacy and educational needs for cultural competence in nursing of Korean nurses].

Science.gov (United States)

Kim, Sun-Hee

2013-02-01

This study was done to investigate the level of transcultural self-efficacy (TSE) and related factors and educational needs for cultural competence in nursing (CCN) of Korean hospital nurses. A self-assessment instrument was used to measure TSE and educational needs for CCN. Questionnaires were completed by 285 nurses working in four Korean hospitals. Descriptive statistics, t-test, ANOVA, Pearson correlation coefficients, and multiple regression were used to analyze the data. Mean TSE score for all items was 4.54 and score for mean CCN educational needs, 5.77. Nurses with master's degrees or higher had significantly higher levels of TSE than nurses with bachelor's degrees. TSE positively correlated with English language proficiency, degrees of interest in multi-culture, degree of experience in caring for multi-cultural clients, and educational needs for CCN. The regression model explained 28% of TSE. Factors affecting TSE were degree of interest in multi-culture, degree of experience in caring for multi-cultural clients, and educational needs for CCN. The results of the study indicate a need for nurse educators to support nurses to strengthen TSE and provide educational program for TSE to provide nurses with strategies for raising interests in cultural diversity and successful experiences of cultural congruent care.

Process-model simulations of cloud albedo enhancement by aerosols in the Arctic

Science.gov (United States)

Kravitz, Ben; Wang, Hailong; Rasch, Philip J.; Morrison, Hugh; Solomon, Amy B.

2014-01-01

A cloud-resolving model is used to simulate the effectiveness of Arctic marine cloud brightening via injection of cloud condensation nuclei (CCN), either through geoengineering or other increased sources of Arctic aerosols. An updated cloud microphysical scheme is employed, with prognostic CCN and cloud particle numbers in both liquid and mixed-phase marine low clouds. Injection of CCN into the marine boundary layer can delay the collapse of the boundary layer and increase low-cloud albedo. Albedo increases are stronger for pure liquid clouds than mixed-phase clouds. Liquid precipitation can be suppressed by CCN injection, whereas ice precipitation (snow) is affected less; thus, the effectiveness of brightening mixed-phase clouds is lower than for liquid-only clouds. CCN injection into a clean regime results in a greater albedo increase than injection into a polluted regime, consistent with current knowledge about aerosol–cloud interactions. Unlike previous studies investigating warm clouds, dynamical changes in circulation owing to precipitation changes are small. According to these results, which are dependent upon the representation of ice nucleation processes in the employed microphysical scheme, Arctic geoengineering is unlikely to be effective as the sole means of altering the global radiation budget but could have substantial local radiative effects. PMID:25404677

Potential indirect effects of aerosol on tropical cyclone intensity: convective fluxes and cold-pool activity

Science.gov (United States)

Krall, G. M.; Cottom, W. R.

2012-01-01

Observational and model evidence suggest that a 2008 Western Pacific typhoon (NURI) ingested elevated concentrations of aerosol as it neared the Chinese coast. This study uses a regional model with two-moment bin-emulating microphysics to simulate the typhoon as it enters the field of elevated aerosol concentrations. A clean maritime field of cloud condensation nuclei (CCN) was prescribed as marine background CCN concentrations and then based on satellite and global aerosol model output, increased to pollution levels and further enhanced in sensitivity tests. The typhoon was simulated for 96 h beginning 17 August 2008. During the final 60 h CCN concentrations were enhanced as it neared the Philippines and coastal China. The model was initialized with both global reanalysis model data and irregularly spaced dropsonde data from the 2008 T-PARC observational campaign using an objective analysis routine. At 36 h, the internal nudging of the model was switched off and allowed to freely evolve on its own. As the typhoon encountered the elevated CCN in the sensitivity tests, a significant perturbation of windspeed, convective fluxes, and hydrometeor species behavior was simulated. Early during the ingestion of enhanced CCN, precipitation was reduced due to suppressed collision and coalescence, and storm winds increased in strength. Subsequently, owing to reduced fall speeds of the smaller drops, greater amounts of condensate were thrust into supercooled levels where the drops froze releasing greater amounts of latent heat of freezing. Convection thereby intensified which resulted in enhanced rainfall and more vigorous convectively-produced downdrafts. As the convection intensified in the outer rainbands the storm drifted over the developing cold-pools. The enhanced cold-pools blocked the inflow of warm, moist air into the core of the typhoon which led to a weakening of the typhoon with significantly reduced low level wind speeds. The very high amounts of pollution

Perceptual category learning and visual processing: An exercise in computational cognitive neuroscience.

Science.gov (United States)

Cantwell, George; Riesenhuber, Maximilian; Roeder, Jessica L; Ashby, F Gregory

2017-05-01

The field of computational cognitive neuroscience (CCN) builds and tests neurobiologically detailed computational models that account for both behavioral and neuroscience data. This article leverages a key advantage of CCN-namely, that it should be possible to interface different CCN models in a plug-and-play fashion-to produce a new and biologically detailed model of perceptual category learning. The new model was created from two existing CCN models: the HMAX model of visual object processing and the COVIS model of category learning. Using bitmap images as inputs and by adjusting only a couple of learning-rate parameters, the new HMAX/COVIS model provides impressively good fits to human category-learning data from two qualitatively different experiments that used different types of category structures and different types of visual stimuli. Overall, the model provides a comprehensive neural and behavioral account of basal ganglia-mediated learning. Copyright © 2017 Elsevier Ltd. All rights reserved.

New particle formation and growth in biomass burning plumes: An important source of cloud condensation nuclei

Science.gov (United States)

Hennigan, Christopher J.; Westervelt, Daniel M.; Riipinen, Ilona; Engelhart, Gabriella J.; Lee, Taehyoung; Collett, Jeffrey L., Jr.; Pandis, Spyros N.; Adams, Peter J.; Robinson, Allen L.

2012-05-01

Experiments were performed in an environmental chamber to characterize the effects of photo-chemical aging on biomass burning emissions. Photo-oxidation of dilute exhaust from combustion of 12 different North American fuels induced significant new particle formation that increased the particle number concentration by a factor of four (median value). The production of secondary organic aerosol caused these new particles to grow rapidly, significantly enhancing cloud condensation nuclei (CCN) concentrations. Using inputs derived from these new data, global model simulations predict that nucleation in photo-chemically aging fire plumes produces dramatically higher CCN concentrations over widespread areas of the southern hemisphere during the dry, burning season (Sept.-Oct.), improving model predictions of surface CCN concentrations. The annual indirect forcing from CCN resulting from nucleation and growth in biomass burning plumes is predicted to be -0.2 W m-2, demonstrating that this effect has a significant impact on climate that has not been previously considered.

Content-centric networks an overview, applications and research challenges

CERN Document Server

Ahmed, Syed Hassan; Kim, Dongkyun

2016-01-01

This book introduces Content-Centric Networking (CCN), a networking paradigm that provides a simple and effective solution to the challenging demands of future wired and wireless communications. It provides an overview of the recent developments in the area of future internet technologies, bringing together the advancements that have been made in Information-Centric Networking (ICN) in general, with a focus on CCN. It begins with an introduction to the basics of CCN is followed by an overview of the current internet paradigm and its challenges. Next, an application perspective has been included, where the authors encompass the selected applications for CCN with recent refereed research and developments. These applications include Internet of Things (IoT), Smart Grid, Vehicular Ad hoc Networks (VANETs), and Wireless Sensor Networks (WSNs). The book is a useful reference source for practising researchers, and can be used as supporting material for undergraduate and graduate level courses in computer science and...

Record High US Measles Cases: Patient Vaccination, Clinical Assessment and Management

Centers for Disease Control (CDC) Podcasts

2014-06-30

This podcast is an overview of the Clinician Outreach and Communication Activity (COCA) Call: Record High US Measles Cases: Patient Vaccination, Clinical Assessment and Management. In May 2014, the United States recorded the largest number of reported measles cases since 1994 and the number continues to rise. Most cases reported have been acquired in the U.S. and are associated with importations from countries where measles is still common. This highly contagious, acute viral illness spreads quickly in unvaccinated populations once reaching the U.S. The recent measles outbreaks highlight the importance of maintaining high vaccination coverage in the U.S. and ensuring age-appropriate vaccination for international travelers. During this COCA call, clinicians will learn the status of measles in the U.S. and CDC vaccination recommendations and guidelines for patient assessment and management.  Created: 6/30/2014 by : National Center for Immunization and Respiratory Diseases; Division of Viral Diseases; Healthcare Preparedness Activity (HPA); Office of Public Health Preparedness and Response (OPHPR).   Date Released: 6/30/2014.

High-dose steroid therapy for idiopathic optic perineuritis: a case series

Directory of Open Access Journals (Sweden)

Mimura Tatsuya

2010-12-01

Full Text Available Abstract Introduction It has been reported that the prognosis of optic perineuritis may be poor when initiation of treatment is delayed. Here we report the successful treatment of three patients with idiopathic optic perineuritis, including two in whom initiation of therapy was delayed. Case presentation Three Japanese patients (two women aged 73 and 66 years, and one man aged 27 years presented with loss of vision (for five months, several months, and two months respectively and pain on eye movement in the third case only, and were diagnosed as having idiopathic optic perineuritis. Fat-suppressed T2-weighted magnetic resonance images showed high signal intensity areas around the affected optic nerves, suggesting the presence of optic perineuritis. Two patients received steroid pulse therapy and the third was given high-dose steroid therapy. The visual acuity improved in all three cases. Conclusion High-dose steroid therapy may be effective for idiopathic perineuritis in patients without optic nerve atrophy, even if initial treatment (including moderate-dose steroids has failed.

Calibration Uncertainties in the Droplet Measurement Technologies Cloud Condensation Nuclei Counter

Science.gov (United States)

Hibert, Kurt James

Cloud condensation nuclei (CCN) serve as the nucleation sites for the condensation of water vapor in Earth's atmosphere and are important for their effect on climate and weather. The influence of CCN on cloud radiative properties (aerosol indirect effect) is the most uncertain of quantified radiative forcing changes that have occurred since pre-industrial times. CCN influence the weather because intrinsic and extrinsic aerosol properties affect cloud formation and precipitation development. To quantify these effects, it is necessary to accurately measure CCN, which requires accurate calibrations using a consistent methodology. Furthermore, the calibration uncertainties are required to compare measurements from different field projects. CCN uncertainties also aid the integration of CCN measurements with atmospheric models. The commercially available Droplet Measurement Technologies (DMT) CCN Counter is used by many research groups, so it is important to quantify its calibration uncertainty. Uncertainties in the calibration of the DMT CCN counter exist in the flow rate and supersaturation values. The concentration depends on the accuracy of the flow rate calibration, which does not have a large (4.3 %) uncertainty. The supersaturation depends on chamber pressure, temperature, and flow rate. The supersaturation calibration is a complex process since the chamber's supersaturation must be inferred from a temperature difference measurement. Additionally, calibration errors can result from the Kohler theory assumptions, fitting methods utilized, the influence of multiply-charged particles, and calibration points used. In order to determine the calibration uncertainties and the pressure dependence of the supersaturation calibration, three calibrations are done at each pressure level: 700, 840, and 980 hPa. Typically 700 hPa is the pressure used for aircraft measurements in the boundary layer, 840 hPa is the calibration pressure at DMT in Boulder, CO, and 980 hPa is the

High accuracy of family history of melanoma in Danish melanoma cases.

Science.gov (United States)

Wadt, Karin A W; Drzewiecki, Krzysztof T; Gerdes, Anne-Marie

2015-12-01

The incidence of melanoma in Denmark has immensely increased over the last 10 years making Denmark a high risk country for melanoma. In the last two decades multiple public campaigns have sought to increase the awareness of melanoma. Family history of melanoma is a known major risk factor but previous studies have shown that self-reported family history of melanoma is highly inaccurate. These studies are 15 years old and we wanted to examine if a higher awareness of melanoma has increased the accuracy of self-reported family history of melanoma. We examined the family history of 181 melanoma probands who reported 199 cases of melanoma in relatives, of which 135 cases where in first degree relatives. We confirmed the diagnosis of melanoma in 77% of all relatives, and in 83% of first degree relatives. In 181 probands we validated the negative family history of melanoma in 748 first degree relatives and found only 1 case of melanoma which was not reported in a 3 case melanoma family. Melanoma patients in Denmark report family history of melanoma in first and second degree relatives with a high level of accuracy with a true positive predictive value between 77 and 87%. In 99% of probands reporting a negative family history of melanoma in first degree relatives this information is correct. In clinical practice we recommend that melanoma diagnosis in relatives should be verified if possible, but even unverified reported melanoma cases in relatives should be included in the indication of genetic testing and assessment of melanoma risk in the family.

Case Study: Fort Mill High School--A Culture of Continuous Improvement

Science.gov (United States)

Southern Regional Education Board (SREB), 2014

2014-01-01

This is the latest in a series of case studies highlighting best practices High Schools That Work (HSTW) network schools and districts are implementing to prepare students better for further studies and careers. Fort Mill High School is in Fort Mill, South Carolina, an outlying suburb of Charlotte, North Carolina. Fort Mill links high quality…

MicroRNA-143-3p inhibits hyperplastic scar formation by targeting connective tissue growth factor CTGF/CCN2 via the Akt/mTOR pathway.

Science.gov (United States)

Mu, Shengzhi; Kang, Bei; Zeng, Weihui; Sun, Yaowen; Yang, Fan

2016-05-01

Post-traumatic hypertrophic scar (HS) is a fibrotic disease with excessive extracellular matrix (ECM) production, which is a response to tissue injury by fibroblasts. Although emerging evidence has indicated that miRNA contributes to hypertrophic scarring, the role of miRNA in HS formation remains unclear. In this study, we found that miR-143-3p was markedly downregulated in HS tissues and fibroblasts (HSFs) using qRT-PCR. The expression of connective tissue growth factor (CTGF/CCN2) was upregulated both in HS tissues and HSFs, which is proposed to play a key role in ECM deposition in HS. The protein expression of collagen I (Col I), collagen III (Col III), and α-smooth muscle actin (α-SMA) was obviously inhibited after treatment with miR-143-3p in HSFs. The CCK-8 assay showed that miR-143-3p transfection reduced the proliferation ability of HSFs, and flow cytometry showed that either early or late apoptosis of HSFs was upregulated by miR-143-3p. In addition, the activity of caspase 3 and caspase 9 was increased after miR-143-3p transfection. On the contrary, the miR-143-3p inhibitor was demonstrated to increase cell proliferation and inhibit apoptosis of HSFs. Moreover, miR-143-3p targeted the 3'-UTR of CTGF and caused a significant decrease of CTGF. Western blot demonstrated that Akt/mTOR phosphorylation and the expression of CTGF, Col I, Col III, and α-SMA were inhibited by miR-143-3p, but increased by CTGF overexpression. In conclusion, we found that miR-143-3p inhibits hypertrophic scarring by regulating the proliferation and apoptosis of human HSFs, inhibiting ECM production-associated protein expression by targeting CTGF, and restraining the Akt/mTOR pathway.

Chemical aging of single and multicomponent biomass burning aerosol surrogate particles by OH: implications for cloud condensation nucleus activity

Directory of Open Access Journals (Sweden)

J. H. Slade

2015-09-01

Full Text Available Multiphase OH and O3 oxidation reactions with atmospheric organic aerosol (OA can influence particle physicochemical properties including composition, morphology, and lifetime. Chemical aging of initially insoluble or low-soluble single-component OA by OH and O3 can increase their water solubility and hygroscopicity, making them more active as cloud condensation nuclei (CCN and susceptible to wet deposition. However, an outstanding problem is whether the effects of chemical aging on their CCN activity are preserved when mixed with other organic or inorganic compounds exhibiting greater water solubility. In this work, the CCN activity of laboratory-generated biomass burning aerosol (BBA surrogate particles exposed to OH and O3 is evaluated by determining the hygroscopicity parameter, κ, as a function of particle type, mixing state, and OH and O3 exposure applying a CCN counter (CCNc coupled to an aerosol flow reactor (AFR. Levoglucosan (LEV, 4-methyl-5-nitrocatechol (MNC, and potassium sulfate (KS serve as representative BBA compounds that exhibit different hygroscopicity, water solubility, chemical functionalities, and reactivity with OH radicals, and thus exemplify the complexity of mixed inorganic/organic aerosol in the atmosphere. The CCN activities of all of the particles were unaffected by O3 exposure. Following exposure to OH, κ of MNC was enhanced by an order of magnitude, from 0.009 to ~ 0.1, indicating that chemically aged MNC particles are better CCN and more prone to wet deposition than pure MNC particles. No significant enhancement in κ was observed for pure LEV particles following OH exposure. κ of the internally mixed particles was not affected by OH oxidation. Furthermore, the CCN activity of OH-exposed MNC-coated KS particles is similar to the OH unexposed atomized 1 : 1 by mass MNC : KS binary-component particles. Our results strongly suggest that when OA is dominated by water-soluble organic carbon (WSOC or inorganic ions

A Pilot Study to Teach Siblings to Support Children with Complex Communication Needs

Science.gov (United States)

Douglas, Sarah N.; Kammes, Rebecca; Nordquist, Erica; D'Agostino, Sophia

2018-01-01

Siblings play an important role in the lives of children with disabilities, especially those with complex communication needs (CCN). However, children with CCN require support to learn social and communication skills. Like other communication partners, typically developing (TD) siblings may struggle to understand how to best interact with a child…

Expression of Connective Tissue Growth Factor in Male Breast Cancer : Clinicopathologic Correlations and Prognostic Value

NARCIS (Netherlands)

Lacle, Miangela M.; van Diest, Paul J.; Goldschmeding, Roel; van der Wall, Elsken; Nguyen, Tri Q.

2015-01-01

Connective tissue growth factor (CTGF/CCN2) is a member of the CCN family of secreted proteins that are believed to play an important role in the development of neoplasia. In particular, CTGF has been reported to play an important role in mammary tumorigenesis and to have prognostic value in female

High Resolution Melting (HRM for High-Throughput Genotyping—Limitations and Caveats in Practical Case Studies

Directory of Open Access Journals (Sweden)

Marcin Słomka

2017-11-01

Full Text Available High resolution melting (HRM is a convenient method for gene scanning as well as genotyping of individual and multiple single nucleotide polymorphisms (SNPs. This rapid, simple, closed-tube, homogenous, and cost-efficient approach has the capacity for high specificity and sensitivity, while allowing easy transition to high-throughput scale. In this paper, we provide examples from our laboratory practice of some problematic issues which can affect the performance and data analysis of HRM results, especially with regard to reference curve-based targeted genotyping. We present those examples in order of the typical experimental workflow, and discuss the crucial significance of the respective experimental errors and limitations for the quality and analysis of results. The experimental details which have a decisive impact on correct execution of a HRM genotyping experiment include type and quality of DNA source material, reproducibility of isolation method and template DNA preparation, primer and amplicon design, automation-derived preparation and pipetting inconsistencies, as well as physical limitations in melting curve distinction for alternative variants and careful selection of samples for validation by sequencing. We provide a case-by-case analysis and discussion of actual problems we encountered and solutions that should be taken into account by researchers newly attempting HRM genotyping, especially in a high-throughput setup.

High Resolution Melting (HRM) for High-Throughput Genotyping—Limitations and Caveats in Practical Case Studies

Science.gov (United States)

Słomka, Marcin; Sobalska-Kwapis, Marta; Wachulec, Monika; Bartosz, Grzegorz

2017-01-01

High resolution melting (HRM) is a convenient method for gene scanning as well as genotyping of individual and multiple single nucleotide polymorphisms (SNPs). This rapid, simple, closed-tube, homogenous, and cost-efficient approach has the capacity for high specificity and sensitivity, while allowing easy transition to high-throughput scale. In this paper, we provide examples from our laboratory practice of some problematic issues which can affect the performance and data analysis of HRM results, especially with regard to reference curve-based targeted genotyping. We present those examples in order of the typical experimental workflow, and discuss the crucial significance of the respective experimental errors and limitations for the quality and analysis of results. The experimental details which have a decisive impact on correct execution of a HRM genotyping experiment include type and quality of DNA source material, reproducibility of isolation method and template DNA preparation, primer and amplicon design, automation-derived preparation and pipetting inconsistencies, as well as physical limitations in melting curve distinction for alternative variants and careful selection of samples for validation by sequencing. We provide a case-by-case analysis and discussion of actual problems we encountered and solutions that should be taken into account by researchers newly attempting HRM genotyping, especially in a high-throughput setup. PMID:29099791

High Resolution Melting (HRM) for High-Throughput Genotyping-Limitations and Caveats in Practical Case Studies.

Science.gov (United States)

Słomka, Marcin; Sobalska-Kwapis, Marta; Wachulec, Monika; Bartosz, Grzegorz; Strapagiel, Dominik

2017-11-03

High resolution melting (HRM) is a convenient method for gene scanning as well as genotyping of individual and multiple single nucleotide polymorphisms (SNPs). This rapid, simple, closed-tube, homogenous, and cost-efficient approach has the capacity for high specificity and sensitivity, while allowing easy transition to high-throughput scale. In this paper, we provide examples from our laboratory practice of some problematic issues which can affect the performance and data analysis of HRM results, especially with regard to reference curve-based targeted genotyping. We present those examples in order of the typical experimental workflow, and discuss the crucial significance of the respective experimental errors and limitations for the quality and analysis of results. The experimental details which have a decisive impact on correct execution of a HRM genotyping experiment include type and quality of DNA source material, reproducibility of isolation method and template DNA preparation, primer and amplicon design, automation-derived preparation and pipetting inconsistencies, as well as physical limitations in melting curve distinction for alternative variants and careful selection of samples for validation by sequencing. We provide a case-by-case analysis and discussion of actual problems we encountered and solutions that should be taken into account by researchers newly attempting HRM genotyping, especially in a high-throughput setup.

Impact of an Engineering Case Study in a High School Pre-Engineering Course

Science.gov (United States)

Rutz, Eugene; Shafer, Michelle

2011-01-01

Students at an all-girls high school who were enrolled in an introduction to engineering course were presented an engineering case study to determine if the case study affected their attitudes toward engineering and their abilities to solve engineering problems. A case study on power plants was implemented during a unit on electrical engineering.…

Case Studies of Leading Edge Small Urban High Schools. Personalization Strategic Designs: 9. MetWest High School

Science.gov (United States)

Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

2008-01-01

This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

Persistent high serum bilirubin level after percutaneous transhepatic biliary drainage: analysis of 32 cases

International Nuclear Information System (INIS)

Choo, In Wook; Choi, Byung Ihn; Park, Jae Hyung; Han, Man Chung; Kim, Chu Wan

1986-01-01

The aim of percutaneous transhepatic biliary drainage (PTBD) is to decrease serum bilirubin level and promote liver function in patient with biliary tract disease, especially obstruction by malignant disease. But some patients showed persistent high serum bilirubin level or higher than pre-PTBD level. Percutaneous transhepatic biliary drainage was performed in 341 patients of obstructive jaundice for 5 years form July, 1981 to July, 1986 at department of radiology, Seoul National University Hospital. Follow up check of the serum bilirubin level was possible in 188 patients. Among them the authors analysed 32 patients who showed persistent high serum bilirubin level after PTBD. The results were as follows: 1. The male to female ratio was 3.4:1 and the age ranged from 33 to 75. 2. The causes of obstructive jaundice included 30 malignant diseases and 2 benign diseases. Malignant disease were 16 cases of bile duct carcinoma, 7 cases of pancreatic cancer and 7 cases of metastasis from stomach, colon and uterine cervix. Benign disease were 1 case of common hepatic duct stone and 1 case of intrahepatic duct stones. 3. The most common level of obstruction was trifurcation in 17 cases. 4. The most common indication of PTBD was palliative drainage of obstruction secondary to malignant tumor in 28 cases. 5. Change of serum bilirubin level ratio (post-PTBD level/pre-PTBD level) was 1.28, 1.22, 1.38, 1.51 in serial period of 1-3 days, 4-6 days, 1-2 week 2-3 week after PTBD. 6. Causes of persistent high serum bilirubin level after PTBD were 12 cases of partial drainage of intrahepatic bile, 13 cases of hepatic dysfunction including 9 cases of metastatic nodule, 2 cases of biliary cirrhosis, 2 cases of multiple liver abscess, and 7 cases of poor function of catheter including 4 cases of hemobilia, 1 case of multiple intrahepatic stones, pyobilia and intrahepatic Clonorchis sinensis.

Persistent high serum bilirubin level after percutaneous transhepatic biliary drainage: analysis of 32 cases

Energy Technology Data Exchange (ETDEWEB)

Choo, In Wook; Choi, Byung Ihn; Park, Jae Hyung; Han, Man Chung; Kim, Chu Wan [Seoul National University College of Medicine, Seoul (Korea, Republic of)

1986-12-15

The aim of percutaneous transhepatic biliary drainage (PTBD) is to decrease serum bilirubin level and promote liver function in patient with biliary tract disease, especially obstruction by malignant disease. But some patients showed persistent high serum bilirubin level or higher than pre-PTBD level. Percutaneous transhepatic biliary drainage was performed in 341 patients of obstructive jaundice for 5 years form July, 1981 to July, 1986 at department of radiology, Seoul National University Hospital. Follow up check of the serum bilirubin level was possible in 188 patients. Among them the authors analysed 32 patients who showed persistent high serum bilirubin level after PTBD. The results were as follows: 1. The male to female ratio was 3.4:1 and the age ranged from 33 to 75. 2. The causes of obstructive jaundice included 30 malignant diseases and 2 benign diseases. Malignant disease were 16 cases of bile duct carcinoma, 7 cases of pancreatic cancer and 7 cases of metastasis from stomach, colon and uterine cervix. Benign disease were 1 case of common hepatic duct stone and 1 case of intrahepatic duct stones. 3. The most common level of obstruction was trifurcation in 17 cases. 4. The most common indication of PTBD was palliative drainage of obstruction secondary to malignant tumor in 28 cases. 5. Change of serum bilirubin level ratio (post-PTBD level/pre-PTBD level) was 1.28, 1.22, 1.38, 1.51 in serial period of 1-3 days, 4-6 days, 1-2 week 2-3 week after PTBD. 6. Causes of persistent high serum bilirubin level after PTBD were 12 cases of partial drainage of intrahepatic bile, 13 cases of hepatic dysfunction including 9 cases of metastatic nodule, 2 cases of biliary cirrhosis, 2 cases of multiple liver abscess, and 7 cases of poor function of catheter including 4 cases of hemobilia, 1 case of multiple intrahepatic stones, pyobilia and intrahepatic Clonorchis sinensis.

Organic aerosols

International Nuclear Information System (INIS)

Penner, J.E.

1994-01-01

Organic aerosols scatter solar radiation. They may also either enhance or decrease concentrations of cloud condensation nuclei. This paper summarizes observed concentrations of aerosols in remote continental and marine locations and provides estimates for the sources of organic aerosol matter. The anthropogenic sources of organic aerosols may be as large as the anthropogenic sources of sulfate aerosols, implying a similar magnitude of direct forcing of climate. The source estimates are highly uncertain and subject to revision in the future. A slow secondary source of organic aerosols of unknown origin may contribute to the observed oceanic concentrations. The role of organic aerosols acting as cloud condensation nuclei (CCN) is described and it is concluded that they may either enhance or decrease the ability of anthropogenic sulfate aerosols to act as CCN

A state-of-the-art report on design technology of communication network in nuclear power plants

International Nuclear Information System (INIS)

Kim, Dong Hoon; Seong, Seung Hwan; Jang, Gwi Sook; Koo, In Soo; Lee, Soon Sung

1996-06-01

This report describe the technical status of commercial communication network (CCN) and application in NPPs. Communication network (CN) is required for effective information exchanges, enhancement of flexibility, and etc. CCN is developing to the trend of high-reliability, high-speed, standardization and integration. Each design element should be analyzed and evaluated as a portion of integrated design. CN in NPP applications is limited to the information processing and monitoring systems. Communication methods used in safety-related systems is the point-to-point link because of conservative approach to the requirements and verification problems. Chapter 1 discusses the purpose of CN, in chapter 2,the technology of CNN such as topology, protocol, media, inter-networking device, performance, standardization and equipment is described. In chapter 3, the status of application in NPP is analyzed and described regarding to structure and characteristics of CN. In chapter 4, as a conclusion, summary of status and prospect for CN is described. (author). 34 refs., 31 tabs., 6 figs

Caracterización de tres índices de cosecha de cacao de los clones CCN51, ICS60 e ICS 95, en la montaña santandereana, Colombia

Directory of Open Access Journals (Sweden)

Lucas Fernando Quintana Fuentes

2015-03-01

Full Text Available En Colombia la región con mayor producción de cacao es la denominada montaña santandereana, que se ubica entre los pisos térmicos cálido y templado donde se cultiva cacao entre los 200 a 1200 msnm. en los departamentos de Santander y Norte de Santander. Esta investigación surge como una necesidad de la Federación nacional de cacaoteros, Fedecacao, con el propósito de construir herramientas que permitan a futuro tomar decisiones sobre el manejo poscosecha del fruto, buscando una mejora continua de la calidad e incrementando así la competitividad en los mercados. El objetivo fue evaluar tres variables: índice de mazorca, índice de grano y porcentaje de cascarilla, según la Norma Técnica Colombiana 1252, en tres franjas altitudinales de la montaña santandereana, para tres clones introducidos: CCN 51, ICS 60 e ICS 95. El seguimiento y análisis de las tres variables se registró en dos cosechas denominadas principal e intermedia, en tres fincas para cada franja altitudinal y en los tres clones. Se determinó la manera cómo esta condición influye en el resultado de estas variables relacionadas con el rendimiento y la calidad, mediante la evaluación de los datos obtenidos a través de métodos estadísticos de correlación y de determinación, estableciéndose que no hay diferencias significativas que permitan concluir que la altitud influye en estas variables de calidad.

High-dose calcium stimulation test in a case of insulinoma masquerading as hysteria.

Science.gov (United States)

Nakamura, Yoshio; Doi, Ryuichiro; Kohno, Yasuhiro; Shimono, Dai; Kuwamura, Naomitsu; Inoue, Koichi; Koshiyama, Hiroyuki; Imamura, Masayuki

2002-11-01

It is reported that some cases with insulinoma present with neuropsychiatric symptoms and are often misdiagnosed as psychosis. Here we report a case of insulinoma masquerading as hysteria, whose final diagnosis could be made using high-dose calcium stimulation test. A 28-yr-old woman was referred presenting with substupor, mutism, mannerism, restlessness, and incoherence. Laboratory examinations revealed hypoglycemia (33 mg/dL) and detectable insulin levels (9.7 microU/mL), suggesting the diagnosis of insulinoma. However, neither imaging studies nor selective arterial calcium injection (SACI) test with a conventional dose of calcium (0.025 mEq/kg) indicated the tumor. High-dose calcium injection (0.05 mEq/kg) evoked insulin secretion when injected into superior mesenteric artery. A solitary tumor in the head of the pancreas was resected, and her plasma glucose returned to normal. Postoperatively, iv injection of secretin resulted in a normal response of insulin, which was not found preoperatively. This case suggests the usefulness of the SACI test with high-dose of calcium in the case of insulinoma when the standard dose fails to detect such a tumor.

High-Grade Transformation of Adenoid Cystic Carcinoma Delineated with a Fibrous Rim: A Case Report

Directory of Open Access Journals (Sweden)

Hamide Sayar

2013-09-01

Full Text Available Background: High-grade transformation or dedifferentiation in carcinoma is progression of a low-grade malignant neoplasm to a high-grade carcinoma or poorly differentiated adenocarcinoma. This is rarely observed in adenoid cystic carcinoma of the salivary glands. Case Report: A 39 year-old woman presented with a painless mass at the left submandibulary region that had been growing slowly for 5 years. Submandibulary mass resection revealed a mass with peripheral adenoid cystic carcinoma and a central high-grade tumor delineated with a fibrous rim, raising the possibility of a hybrid or composite carcinoma, requiring differential diagnosis depending upon morphology and immunohistochemistry findings. The final histopathological diagnosis was high-grade transformation of adenoid cystic carcinoma. After surgical therapy, the patient was irradiated to the neck and submandibulary region. No sign of tumor recurrence has been evident for 36 months. Conclusion: This present case seems to be another rare case with high-grade transformation of adenoid cystic carcinoma and the fibrous rim may be a histopathological feature of such cases, which should be kept in mind.

High-order conservative discretizations for some cases of the rigid body motion

International Nuclear Information System (INIS)

Kozlov, Roman

2008-01-01

Modified vector fields can be used to construct high-order structure-preserving numerical integrators for ordinary differential equations. In the present Letter we consider high-order integrators based on the implicit midpoint rule, which conserve quadratic first integrals. It is shown that these integrators are particularly suitable for the rigid body motion with an additional quadratic first integral. In this case high-order integrators preserve all four first integrals of motion. The approach is illustrated on the Lagrange top (a rotationally symmetric rigid body with a fixed point on the symmetry axis). The equations of motion are considered in the space fixed frame because in this frame Lagrange top admits a neat description. The Lagrange top motion includes the spherical pendulum and the planar pendulum, which swings in a vertical plane, as particular cases

Particle growth kinetics over the Amazon rainforest

Science.gov (United States)

Pinterich, T.; Andreae, M. O.; Artaxo, P.; Kuang, C.; Longo, K.; Machado, L.; Manzi, A. O.; Martin, S. T.; Mei, F.; Pöhlker, C.; Pöhlker, M. L.; Poeschl, U.; Shilling, J. E.; Shiraiwa, M.; Tomlinson, J. M.; Zaveri, R. A.; Wang, J.

2016-12-01

Aerosol particles larger than 100 nm play a key role in global climate by acting as cloud condensation nuclei (CCN). Most of these particles, originated from new particle formation or directly emitted into the atmospheric, are initially too small to serve as CCN. These small particles grow to CCN size mainly through condensation of secondary species. In one extreme, the growth is dictated by kinetic condensation of very low-volatility compounds, favoring the growth of the smallest particles; in the other extreme, the process is driven by Raoult's law-based equilibrium partitioning of semi-volatile organic compound, favoring the growth of larger particles. These two mechanisms can lead to very different production rates of CCN. The growth of particles depends on a number of parameters, including the volatility of condensing species, particle phase, and diffusivity inside the particles, and this process is not well understood in part due to lack of ambient data. Here we examine atmospheric particle growth using high-resolution size distributions measured onboard the DOE G-1 aircraft during GoAmazon campaign, which took place from January 2014 to December 2015 near Manaus, Brazil, a city surrounded by natural forest for over 1000 km in every direction. City plumes are clearly identified by the strong enhancement of nucleation and Aitken mode particle concentrations over the clean background. As the plume traveled downwind, particle growth was observed, and is attributed to condensation of secondary species and coagulation (Fig.1). Observed aerosol growth is modeled using MOSAIC (Model for Simulating Aerosol Interactions and Chemistry), which dynamically partitions multiple compounds to all particle size bins by taking into account compound volatility, gas-phase diffusion, interfacial mass accommodation, particle-phase diffusion, and particle-phase reaction. The results from both wet and dry seasons will be discussed.

The magnitude and causes of uncertainty in global model simulations of cloud condensation nuclei

Directory of Open Access Journals (Sweden)

L. A. Lee

2013-09-01

Full Text Available Aerosol–cloud interaction effects are a major source of uncertainty in climate models so it is important to quantify the sources of uncertainty and thereby direct research efforts. However, the computational expense of global aerosol models has prevented a full statistical analysis of their outputs. Here we perform a variance-based analysis of a global 3-D aerosol microphysics model to quantify the magnitude and leading causes of parametric uncertainty in model-estimated present-day concentrations of cloud condensation nuclei (CCN. Twenty-eight model parameters covering essentially all important aerosol processes, emissions and representation of aerosol size distributions were defined based on expert elicitation. An uncertainty analysis was then performed based on a Monte Carlo-type sampling of an emulator built for each model grid cell. The standard deviation around the mean CCN varies globally between about ±30% over some marine regions to ±40–100% over most land areas and high latitudes, implying that aerosol processes and emissions are likely to be a significant source of uncertainty in model simulations of aerosol–cloud effects on climate. Among the most important contributors to CCN uncertainty are the sizes of emitted primary particles, including carbonaceous combustion particles from wildfires, biomass burning and fossil fuel use, as well as sulfate particles formed on sub-grid scales. Emissions of carbonaceous combustion particles affect CCN uncertainty more than sulfur emissions. Aerosol emission-related parameters dominate the uncertainty close to sources, while uncertainty in aerosol microphysical processes becomes increasingly important in remote regions, being dominated by deposition and aerosol sulfate formation during cloud-processing. The results lead to several recommendations for research that would result in improved modelling of cloud–active aerosol on a global scale.

Adsorption of Pb(II) from fish sauce using carboxylated cellulose nanocrystal: Isotherm, kinetics, and thermodynamic studies.

Science.gov (United States)

Wang, Nan; Jin, Ru-Na; Omer, A M; Ouyang, Xiao-Kun

2017-09-01

In the present study, a new adsorbent based on carboxylated cellulose nanocrystal (CCN) was developed for the adsorption of Pb(II) from fish sauce. The prepared adsorbent material was characterized by zeta potential, FT-IR, XRD, and XPS tools. The changes in the morphological structure of the developed CCN surface were evidenced by SEM and TEM. The favorable adsorption conditions were selected by studying the contact time, initial concentration, temperature, and concentration of the used glutamic acid and NaCl. The results indicated that the Langmuir isotherm model agrees very well with experimental adsorption data (R 2 =0.9962) with a maximum adsorption capacity 232.56mg/g of Pb(II) at 293.2K. Additionally, data of the adsorption kinetics follow the pseudo-second-order kinetics (R 2 >0.9990). On the other hand, the thermodynamics studies show that the adsorption process is spontaneous and endothermic. Furthermore, the developed CCN could be regenerated using acid treatment with a good reusability for Pb(II) adsorption. The results clearly indicated that the synthesized CCN could be effectively applied as a new material for Pb(II) adsorption from fish sauce solutions. Copyright © 2017 Elsevier B.V. All rights reserved.

Broadening of cloud droplet spectra through turbulent entrainment and eddy hopping

Science.gov (United States)

Abade, Gustavo; Grabowski, Wojciech; Pawlowska, Hanna

2017-11-01

This work discusses the effect of cloud turbulence and turbulent entrainment on the evolution of the cloud droplet-size spectrum. We simulate an ensemble of idealized turbulent cloud parcels that are subject to entrainment events, modeled as a random Poisson process. Entrainment events, subsequent turbulent mixing inside the parcel, supersaturation fluctuations, and the resulting stochastic droplet growth by condensation are simulated using a Monte Carlo scheme. Quantities characterizing the turbulence intensity, entrainment rate and the mean fraction of environmental air entrained in an event are specified as external parameters. Cloud microphysics is described by applying Lagrangian particles, the so-called superdroplets. They are either unactivated cloud condensation nuclei (CCN) or cloud droplets that form from activated CCN. The model accounts for the transport of environmental CCN into the cloud by the entraining eddies at the cloud edge. Turbulent mixing of the entrained dry air with cloudy air is described using a linear model. We show that turbulence plays an important role in aiding entrained CCN to activate, providing a source of small cloud droplets and thus broadening the droplet size distribution. Further simulation results will be reported at the meeting.

Teaching Ambition: A Case Study of High School Music Students

Science.gov (United States)

Draves, Tami

2012-01-01

Music teacher socialisation (MTS) has received increased attention in music education research, but few researchers have explored MTS with students during their primary socialisation, or pre-college, years. The purpose of this qualitative multiple case study was to examine the perspectives of high school music students who plan to pursue a music…

High altitude pulmonary edema. Report of a case with familiar history

International Nuclear Information System (INIS)

Velasquez, Jurg Niederbacher; Rueda Manrique, Adriana L; Sanabria Pico, Carmen E

1998-01-01

We report the case of a ten years old child, who presented a high altitude pulmonary edema. His father had the same disorder ten years ago. In addition we review the physiopathology, diagnosis and management of this disease

Metastatic pulmonary calcification: high-resolution computed tomography findings in 23 cases

Directory of Open Access Journals (Sweden)

Luciana Camara Belém

Full Text Available Abstract Objective: The aim of this study was to evaluate the high-resolution computed tomography (HRCT findings in patients diagnosed with metastatic pulmonary calcification (MPC. Materials and Methods: We retrospectively reviewed the HRCT findings from 23 cases of MPC [14 men, 9 women; mean age, 54.3 (range, 26-89 years]. The patients were examined between 2000 and 2014 in nine tertiary hospitals in Brazil, Chile, and Canada. Diagnoses were established by histopathologic study in 18 patients and clinical-radiological correlation in 5 patients. Two chest radiologists analyzed the images and reached decisions by consensus. Results: The predominant HRCT findings were centrilobular ground-glass nodules (n = 14; 60.9%, consolidation with high attenuation (n = 10; 43.5%, small dense nodules (n = 9; 39.1%, peripheral reticular opacities associated with small calcified nodules (n = 5; 21.7%, and ground-glass opacities without centrilobular ground-glass nodular opacity (n = 5; 21.7%. Vascular calcification within the chest wall was found in four cases and pleural effusion was observed in five cases. The abnormalities were bilateral in 21 cases. Conclusion: MPC manifested with three main patterns on HRCT, most commonly centrilobular ground-glass nodules, often containing calcifications, followed by dense consolidation and small solid nodules, most of which were calcified. We also described another pattern of peripheral reticular opacities associated with small calcified nodules. These findings should suggest the diagnosis of MPC in the setting of hypercalcemia.

Metastatic pulmonary calcification: high-resolution computed tomography findings in 23 cases

Energy Technology Data Exchange (ETDEWEB)

Belem, Luciana Camara; Souza, Carolina A.; Souza Junior, Arthur Soares; Escuissato, Dante Luiz; Hochhegger, Bruno; Nobre, Luiz Felipe; Rodrigues, Rosana Souza; Gomes, Antonio Carlos Portugal; Silva, Claudio S.; Guimaraes, Marcos Duarte; Zanetti, Glaucia; Marchiori, Edson, E-mail: edmarchiori@gmail.com [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil); Ottawa Hospital Research Institute, University of Ottawa, (Canada); Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil); Ultra X, Sao Jose do Rio Preto, SP (Brazil); Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil); Universidade Federal de Ciencias da Saude de Porto Alegre (UFCSPA), Porto Alegre, RS (Brazil); Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Hospital Universitario

2017-07-15

Objective: The aim of this study was to evaluate the high-resolution computed tomography (HRCT) findings in patients diagnosed with metastatic pulmonary calcification (MPC). Materials and Methods: We retrospectively reviewed the HRCT findings from 23 cases of MPC [14 men, 9 women; mean age, 54.3 (range, 26-89) years]. The patients were examined between 2000 and 2014 in nine tertiary hospitals in Brazil, Chile, and Canada. Diagnoses were established by histopathologic study in 18 patients and clinical-radiological correlation in 5 patients. Two chest radiologists analyzed the images and reached decisions by consensus. Results: The predominant HRCT findings were centrilobular ground-glass nodules (n = 14; 60.9%), consolidation with high attenuation (n = 10; 43.5%), small dense nodules (n = 9; 39.1%), peripheral reticular opacities associated with small calcified nodules (n = 5; 21.7%), and ground-glass opacities without centrilobular ground-glass nodular opacity (n = 5; 21.7%). Vascular calcification within the chest wall was found in four cases and pleural effusion was observed in five cases. The abnormalities were bilateral in 21 cases. Conclusion: MPC manifested with three main patterns on HRCT, most commonly centrilobular ground-glass nodules, often containing calcifications, followed by dense consolidation and small solid nodules, most of which were calcified. We also described another pattern of peripheral reticular opacities associated with small calcified nodules. These findings should suggest the diagnosis of MPC in the setting of hypercalcemia. (author)

Metastatic pulmonary calcification: high-resolution computed tomography findings in 23 cases

International Nuclear Information System (INIS)

Belem, Luciana Camara; Souza, Carolina A.; Souza Junior, Arthur Soares; Escuissato, Dante Luiz; Hochhegger, Bruno; Nobre, Luiz Felipe; Rodrigues, Rosana Souza; Gomes, Antonio Carlos Portugal; Silva, Claudio S.; Guimaraes, Marcos Duarte; Zanetti, Glaucia; Marchiori, Edson; Ottawa Hospital Research Institute, University of Ottawa,; Faculdade de Medicina de Sao Jose do Rio Preto; Ultra X, Sao Jose do Rio Preto, SP; Universidade Federal do Parana; Universidade Federal de Ciencias da Saude de Porto Alegre; Universidade Federal de Santa Catarina

2017-01-01

Objective: The aim of this study was to evaluate the high-resolution computed tomography (HRCT) findings in patients diagnosed with metastatic pulmonary calcification (MPC). Materials and Methods: We retrospectively reviewed the HRCT findings from 23 cases of MPC [14 men, 9 women; mean age, 54.3 (range, 26-89) years]. The patients were examined between 2000 and 2014 in nine tertiary hospitals in Brazil, Chile, and Canada. Diagnoses were established by histopathologic study in 18 patients and clinical-radiological correlation in 5 patients. Two chest radiologists analyzed the images and reached decisions by consensus. Results: The predominant HRCT findings were centrilobular ground-glass nodules (n = 14; 60.9%), consolidation with high attenuation (n = 10; 43.5%), small dense nodules (n = 9; 39.1%), peripheral reticular opacities associated with small calcified nodules (n = 5; 21.7%), and ground-glass opacities without centrilobular ground-glass nodular opacity (n = 5; 21.7%). Vascular calcification within the chest wall was found in four cases and pleural effusion was observed in five cases. The abnormalities were bilateral in 21 cases. Conclusion: MPC manifested with three main patterns on HRCT, most commonly centrilobular ground-glass nodules, often containing calcifications, followed by dense consolidation and small solid nodules, most of which were calcified. We also described another pattern of peripheral reticular opacities associated with small calcified nodules. These findings should suggest the diagnosis of MPC in the setting of hypercalcemia. (author)

Altered resting state functional connectivity of the cognitive control network in fibromyalgia and the modulation effect of mind-body intervention.

Science.gov (United States)

Kong, Jian; Wolcott, Emily; Wang, Zengjian; Jorgenson, Kristen; Harvey, William F; Tao, Jing; Rones, Ramel; Wang, Chenchen

2018-05-02

This study examines altered resting state functional connectivity (rsFC) of the cognitive control network (CCN) in fibromyalgia patients as compared to healthy controls, as well as how an effective mind-body intervention, Tai Chi, can modulate the altered rsFC of the CCN. Patients with fibromyalgia and matched healthy subjects were recruited in this study. Fibromyalgia patients were scanned 12 weeks before and after intervention. The bilateral dorsolateral prefrontal cortex (DLPFC) was used as a seed to explore the rsFC of the CCN. Data analysis was conducted with 21 patients and 20 healthy subjects. Compared to healthy subjects, fibromyalgia patients exhibited increased rsFC between the DLPFC and the bilateral rostral anterior cingulate cortex (rACC) and medial prefrontal cortex (MPFC) at baseline. The rsFC between the CCN and rACC/MPFC further increased after Tai Chi intervention, and this increase was accompanied by clinical improvements. This rsFC change was also significantly associated with corresponding changes in the Overall Impact domain of the Revised Fibromyalgia Impact Questionnaire (FIQR). Further analysis showed that the rACC/MPFC rsFC with both the PAG and hippocampus significantly decreased following Tai Chi intervention. Our study suggests that fibromyalgia is associated with altered CCN rsFC and that effective mind-body treatment may elicit clinical improvements by further increasing this altered rsFC. Elucidating this mechanism of enhancing the allostasis process will deepen our understanding of the mechanisms underlying mind-body interventions in fibromyalgia patients and facilitate the development of new pain management methods.

Atrial fibrillation in healthy adolescents after highly caffeinated beverage consumption: two case reports

Science.gov (United States)

2011-01-01

Introduction Energy drinks and highly caffeinated drinks comprise some of the fastest growing products of the beverage industry, often targeting teenagers and young adults. Cardiac arrhythmias in children related to high caffeine consumption have not been well described in the literature. This case series describes the possible association between the consumption of highly caffeinated drinks and the subsequent development of atrial fibrillation in the adolescent population. Case presentations We report the cases of two Caucasian adolescent boys of 14 and 16 years of age at the time of presentation, each without a significant cardiac history, who presented with palpitations or vague chest discomfort or both after a recent history of excessive caffeine consumption. Both were found to have atrial fibrillation on electrocardiogram; one patient required digoxin to restore a normal sinus rhythm, and the other self-converted after intravenous fluid administration. Conclusion With the increasing popularity of energy drinks in the pediatric and adolescent population, physicians should be aware of the arrhythmogenic potential associated with highly caffeinated beverage consumption. It is important for pediatricians to understand the lack of regulation in the caffeine content and other ingredients of these high-energy beverages and their complications so that parents and children can be educated about the risk of cardiac arrhythmias with excessive energy drink consumption. PMID:21247417

Atrial fibrillation in healthy adolescents after highly caffeinated beverage consumption: two case reports

Directory of Open Access Journals (Sweden)

Heyden Marybeth

2011-01-01

Full Text Available Abstract Introduction Energy drinks and highly caffeinated drinks comprise some of the fastest growing products of the beverage industry, often targeting teenagers and young adults. Cardiac arrhythmias in children related to high caffeine consumption have not been well described in the literature. This case series describes the possible association between the consumption of highly caffeinated drinks and the subsequent development of atrial fibrillation in the adolescent population. Case presentations We report the cases of two Caucasian adolescent boys of 14 and 16 years of age at the time of presentation, each without a significant cardiac history, who presented with palpitations or vague chest discomfort or both after a recent history of excessive caffeine consumption. Both were found to have atrial fibrillation on electrocardiogram; one patient required digoxin to restore a normal sinus rhythm, and the other self-converted after intravenous fluid administration. Conclusion With the increasing popularity of energy drinks in the pediatric and adolescent population, physicians should be aware of the arrhythmogenic potential associated with highly caffeinated beverage consumption. It is important for pediatricians to understand the lack of regulation in the caffeine content and other ingredients of these high-energy beverages and their complications so that parents and children can be educated about the risk of cardiac arrhythmias with excessive energy drink consumption.

Bupropion Shows Different Effects on Brain Functional Connectivity in Patients With Internet-Based Gambling Disorder and Internet Gaming Disorder

Directory of Open Access Journals (Sweden)

Sujin Bae

2018-04-01

Full Text Available IntroductionInternet gaming disorder (IGD and gambling disorder (GD share similar clinical characteristics but show different brain functional connectivity patterns. Bupropion is known to be effective for the treatment of patients with IGD and GD. We hypothesized that bupropion may be effective for the treatment of Internet-based gambling disorder (ibGD and IGD and that the connections between the default mode network (DMN and cognitive control network (CCN would be different between ibGD and IGD patients after 12 weeks of bupropion treatment.Methods16 patients with IGD, 15 patients with ibGD, and 15 healthy subjects were recruited in this study. At baseline and after 12 weeks of bupropion treatment, the clinical symptoms of patients with IGD or ibGD were assessed, and brain activity was evaluated using resting state functional magnetic resonance imaging.ResultsAfter the 12-week bupropion treatment, clinical symptoms, including the severity of IGD or GD, depressive symptoms, attention, and impulsivity improved in both groups. In the IGD group, the functional connectivity (FC within the posterior DMN as well as the FC between the DMN and the CCN decreased following treatment. Moreover, the FC within the DMN in the IGD group was positively correlated with changes in Young Internet Addiction Scale scores after the bupropion treatment period. In the ibGD group, the FC within the posterior DMN decreased while the FC within the CCN increased after the bupropion treatment period. Moreover, the FC within the CCN in the ibGD group was significantly greater than that in the IGD group.ConclusionBupropion was effective in improving clinical symptoms in patients with IGD and ibGD. However, there were differences in the pharmacodynamics between the two groups. After 12 weeks of bupropion treatment, the FC within the DMN as well as between the DMN and CCN decreased in patients with IGD, whereas the FC within the CCN increased in patients with ibGD.

Bupropion Shows Different Effects on Brain Functional Connectivity in Patients With Internet-Based Gambling Disorder and Internet Gaming Disorder.

Science.gov (United States)

Bae, Sujin; Hong, Ji Sun; Kim, Sun Mi; Han, Doug Hyun

2018-01-01

Internet gaming disorder (IGD) and gambling disorder (GD) share similar clinical characteristics but show different brain functional connectivity patterns. Bupropion is known to be effective for the treatment of patients with IGD and GD. We hypothesized that bupropion may be effective for the treatment of Internet-based gambling disorder (ibGD) and IGD and that the connections between the default mode network (DMN) and cognitive control network (CCN) would be different between ibGD and IGD patients after 12 weeks of bupropion treatment. 16 patients with IGD, 15 patients with ibGD, and 15 healthy subjects were recruited in this study. At baseline and after 12 weeks of bupropion treatment, the clinical symptoms of patients with IGD or ibGD were assessed, and brain activity was evaluated using resting state functional magnetic resonance imaging. After the 12-week bupropion treatment, clinical symptoms, including the severity of IGD or GD, depressive symptoms, attention, and impulsivity improved in both groups. In the IGD group, the functional connectivity (FC) within the posterior DMN as well as the FC between the DMN and the CCN decreased following treatment. Moreover, the FC within the DMN in the IGD group was positively correlated with changes in Young Internet Addiction Scale scores after the bupropion treatment period. In the ibGD group, the FC within the posterior DMN decreased while the FC within the CCN increased after the bupropion treatment period. Moreover, the FC within the CCN in the ibGD group was significantly greater than that in the IGD group. Bupropion was effective in improving clinical symptoms in patients with IGD and ibGD. However, there were differences in the pharmacodynamics between the two groups. After 12 weeks of bupropion treatment, the FC within the DMN as well as between the DMN and CCN decreased in patients with IGD, whereas the FC within the CCN increased in patients with ibGD.

RNA-Seq Based Identification of Candidate Parasitism Genes of Cereal Cyst Nematode (Heterodera avenae during Incompatible Infection to Aegilops variabilis.

Directory of Open Access Journals (Sweden)

Minghui Zheng

Full Text Available One of the reasons for the progressive yield decline observed in cereals production is the rapid build-up of populations of the cereal cyst nematode (CCN, Heterodera avenae. These nematodes secrete so-call effectors into their host plant to suppress the plant defense responses, alter plant signaling pathways and then induce the formation of syncytium after infection. However, little is known about its molecular mechanism and parasitism during incompatible infection. To gain insight into its repertoire of parasitism genes, we investigated the transcriptome of the early parasitic second-stage (30 hours, 3 days and 9 days post infection juveniles of the CCN as well as the CCN infected tissue of the host Aegilops variabilis by Illumina sequencing. Among all assembled unigenes, 681 putative genes of parasitic nematode were found, in which 56 putative effectors were identified, including novel pioneer genes and genes corresponding to previously reported effectors. All the 681 CCN unigenes were mapped to 229 GO terms and 200 KEGG pathways, including growth, development and several stimulus-related signaling pathways. Sixteen clusters were involved in the CCN unigene expression atlas at the early stages during infection process, and three of which were significantly gene-enriched. Besides, the protein-protein interaction network analysis revealed 35 node unigenes which may play an important role in the plant-CCN interaction. Moreover, in a comparison of differentially expressed genes between the pre-parasitic juveniles and the early parasitic juveniles, we found that hydrolase activity was up-regulated in pre J2s whereas binding activity was upregulated in infective J2s. RT-qPCR analysis on some selected genes showed detectable expression, indicating possible secretion of the proteins and putative role in infection. This study provided better insights into the incompatible interaction between H. avenae and the host plant Ae. varabilis. Moreover, RNAi

The Impact of High-Profile Sexual Abuse Cases in the Media on a Pediatric Emergency Department.

Science.gov (United States)

Flannery, Dustin D; Stephens, Clare L; Thompson, Amy D

2016-01-01

High-profile media cases of sexual abuse may encourage disclosures of abuse from victims of unrelated assaults and also influence parental concerns, leading to increased emergency department visits. In the region of the study authors' institution, there are two recent high-profile sexual abuse cases with media coverage: Earl Bradley, a Delaware pediatrician, and Jerry Sandusky, a Pennsylvania college football coach. This is a retrospective cohort study of children evaluated for sexual abuse at a pediatric emergency department. Patients were classified as either presenting during a media period or non-media period. The media periods were one-month periods immediately following breaking news reports, when the cases were highly publicized in the media. The non-media periods were the 12-month periods directly preceding the first reports. The median number of emergency department visits per month during a non-media period was 9 visits (interquartile range 6-10). There were 11 visits in the month following the Sandusky case and 13 visits following the Bradley case. There was no statistical difference in number of emergency department visits for sexual abuse between the periods (p = .09). These finding have implications regarding use of resources in pediatric EDs after high-profile sexual abuse cases.

Organic Aerosols as Cloud Condensation Nuclei

Science.gov (United States)

Hudson, J. G.

2002-05-01

The large organic component of the atmospheric aerosol contributes to both natural and anthropogenic cloud condensation nuclei (CCN). Moreover, some organic substances may reduce droplet surface tension (Facchini et al. 1999), while others may be partially soluble (Laaksonen et al. 1998), and others may inhibit water condensation. The interaction of organics with water need to be understood in order to better understand the indirect aerosol effect. Therefore, laboratory CCN spectral measurements of organic aerosols are presented. These are measurements of the critical supersaturation (Sc), the supersaturation needed to produce an activated cloud droplet, as a function of the size of the organic particles. Substances include sodium lauryl (dodecyl) sulfate, oxalic, adipic, pinonic, hexadecanedioic, glutaric, stearic, succinic, phthalic, and benzoic acids. These size-Sc relationships are compared with theoretical and measured size-Sc relationships of common inorganic compounds (e.g., NaCl, KI, ammonium and calcium sulfate). Unlike most inorganics some organics display variations in solubility per unit mass as a function of particle size. Those showing relatively greater solubility at smaller sizes may be attributable to surface tension reduction, which is greater for less water dilution, as is the case for smaller particles, which are less diluted at the critical sizes. This was the case for sodium dodecyl sulfate, which does reduce surface tension. Relatively greater solubility for larger particles may be caused by greater dissolution at the higher dilutions that occur with larger particles; this is partial solubility. Measurements are also presented of internal mixtures of various organic and inorganic substances. These measurements were done with two CCN spectrometers (Hudson 1989) operating simultaneously. These two instruments usually displayed similar results in spite of the fact that they have different flow rates and supersaturation profiles. The degree of

A Case of High Mortality, Treated with Multidisciplinary Approach in Intensive Care: Meningococcal Meningitis

Directory of Open Access Journals (Sweden)

Mehtap Pehlivanlar Küçük

2018-04-01

Full Text Available Meningococcemia is a highly mortal disease that can cause septic shock and multiple organ failure, which can be accompanied by sudden onset, rapid course, purpura fulminans and diffuse intravenous coagulation tables. Mortality increases when meningococcal causes to meningitis. The fact that it is the cause of neurological sequelae and extremity losses even in the recovering cases makes the support provided by the intensive care unit quite important in the management of cases. A case with meningococcal meningitis with high mortality, who was successfully treated through the use of supportive methods, such as monitorization, mechanical ventilation practices with new modalities, plasmapheresis and sympathetic ganglion blockage, has been presented in company with the literature.

Pulmonary malaria: high-resolution computed tomography findings - a case report

International Nuclear Information System (INIS)

Rodrigues, Rosana; Souza, Daniel Andrade Tinoco de; Marchiori, Edson

2004-01-01

We report the case of a 38-year-old man with pulmonary malaria. High-resolution computed tomography showed thickening of the peribronchovascular interstitium and interlobular septa, areas of consolidation and ground glass attenuation and bilateral pleural effusion suggesting pulmonary edema. The patient recovered well after receiving specific treatment and was discharged after 11 days of hospitalization. (author)

Communication access to businesses and organizations for people with complex communication needs.

Science.gov (United States)

Collier, Barbara; Blackstone, Sarah W; Taylor, Andrew

2012-12-01

Human rights legislation and anti-discrimination and accessibility laws exist in many countries and through international conventions and treaties. To varying degrees, these laws protect the rights of people with disabilities to full and equal access to goods and services. Yet, the accessibility requirements of people with complex communication needs (CCN) are not well represented in the existing accessibility literature. This article describes the results of surveys completed by disability service providers and individuals with CCN due to cerebral palsy, developmental delay, and acquired disabilities. It identifies accessibility requirements for people with CCN for face-to-face communication; comprehension of spoken language; telephone communication; text and print-based communication; Internet, email, and social media interactions; and written communication. Recommendations are made for communication accessibility accommodations in regulations, guidelines, and practices.

Case Studies of Leading Edge Small Urban High Schools. Core Academic Strategic Designs: 2. Noble Street Charter High School

Science.gov (United States)

Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

2008-01-01

This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

Biological dosimetry in cases gives occupational high exposition to ionizing radiations

International Nuclear Information System (INIS)

Ramalho, Adriana T.; Costa, Maria Lucia P.; Oliveira, Monica S.; Silva, Francisco Cesar A.

1998-01-01

From 1983 the cytogenetics dosimetry method it has been used as routine in the IRD laboratory in the period 1983 at 1997 but a high exposition occupational case the physical dosimeters happened in Brazil they were investigated through the cytogenetics dosimetry technique. This technique is employ when the dosimetry personal marks a high dose to 100 mSv (0,1 Gy) that is the cut-off minimum detected in the dosimetry cytogenetics

Primary treatment of acromegaly with high-dose lanreotide: a case series

Directory of Open Access Journals (Sweden)

Cordes Uwe

2010-03-01

Full Text Available Abstract Introduction The first-line treatment for acromegaly is transsphenoidal surgery. In approximately 50% of patients, however, a cure is not possible with surgery and alternatives are needed. Somatostatin analog therapy is the recommended first-line treatment in patients with such cases. Here we provide the first report of a high-dose lanreotide primary therapy in patients with acromegaly. Case presentation Six patients who were not suitable for surgery were given 60 mg of lanreotide (Autogel® every four weeks. All patients were German nationals and Caucasian. When the response of our patients was unsatisfactory, the dose was increased sequentially to 90 mg every four weeks, 120 mg every four weeks, 120 mg every three weeks and 180 mg every three weeks. Treatment duration was 12 to 24 months. In all cases, the lanreotide dose was 120 mg every 4 weeks or higher. In five of our patients, growth hormone (GH levels were successfully reduced (in three patients GH Tumor shrinkage or degeneration was observed in the five responding patients. No drug-related adverse events were noted. Conclusions These results suggest that lanreotide at high doses of 120 mg every four weeks or more is an effective first-line therapy for patients with acromegaly that surgery alone cannot treat.

Comparison of Aerosol Classification Results from Airborne High Spectral Resolution Lidar (HSRL) Measurements and the Calipso Vertical Feature Mask

Science.gov (United States)

Burton, S. P.; Ferrare, R. A.; Hostetler, C. A.; Hair, J. W.; Rogers, R. R.; Obland, M. D.; Butler, C. F.; Cook, A. L.; Harper, D. B.; Froyd, K. D.;

Confidence improvement of disosal safety bydevelopement of a safety case for high-level radioactive waste disposal

Energy Technology Data Exchange (ETDEWEB)

Baik, Min Hoon; Ko, Nak Youl; Jeong, Jong Tae; Kim, Kyung Su [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-12-15

Many countries have developed a safety case suitable to their own countries in order to improve the confidence of disposal safety in deep geological disposal of high-level radioactive waste as well as to develop a disposal program and obtain its license. This study introduces and summarizes the meaning, necessity, and development process of the safety case for radioactive waste disposal. The disposal safety is also discussed in various aspects of the safety case. In addition, the status of safety case development in the foreign countries is briefly introduced for Switzerland, Japan, the United States of America, Sweden, and Finland. The strategy for the safety case development that is being developed by KAERI is also briefly introduced. Based on the safety case, we analyze the efforts necessary to improve confidence in disposal safety for high-level radioactive waste. Considering domestic situations, we propose and discuss some implementing methods for the improvement of disposal safety, such as construction of a reliable information database, understanding of processes related to safety, reduction of uncertainties in safety assessment, communication with stakeholders, and ensuring justice and transparency. This study will contribute to the understanding of the safety case for deep geological disposal and to improving confidence in disposal safety through the development of the safety case in Korea for the disposal of high-level radioactive waste.

Multi-layer casing of a steam turbine for high steam pressures and temperatures

International Nuclear Information System (INIS)

Remberg, A.

1978-01-01

In previous turbine casings there is no sealing provided between the inner layer and the outer layer, so that the steam pressure acts fully on the casing top and on the shaft seal housing situated there. To reduce the displacement which occurs there due to pressure differences in the various steam spaces, the normal inner casing is made with the shaft sealing housing in an inner layer, which cannot be divided in the axial direction. The inner layer can be inserted from the high pressure side into the unit outer casing. A horizontal section through the turbine in the attached drawing makes the construction and operation of the invention clear. (GL) [de

Increased cloud activation potential of secondary organic aerosol for atmospheric mass loadings

Directory of Open Access Journals (Sweden)

S. M. King

2009-05-01

Full Text Available The effect of organic particle mass loading from 1 to ≥100 μg m⁻³ on the cloud condensation nuclei (CCN properties of mixed organic-sulfate particles was investigated in the Harvard Environmental Chamber. Mixed particles were produced by the condensation of organic molecules onto ammonium sulfate particles during the dark ozonolysis of α-pinene. A continuous-flow mode of the chamber provided stable conditions over long time periods, allowing for signal integration and hence increased measurement precision at low organic mass loadings representative of atmospheric conditions. CCN activity was measured at eight mass loadings for 80- and 100-nm particles grown on 50-nm sulfate seeds. A two-component (organic/sulfate Köhler model, which included the particle heterogeneity arising from DMA size selection and from organic volume fraction for the selected 80- and 100-nm particles, was used to predict CCN activity. For organic mass loadings of 2.9 μg m⁻³ and greater, the observed activation curves were well predicted using a single set of physicochemical parameters for the organic component. For mass loadings of 1.74 μg m⁻³ and less, the observed CCN activity increased beyond predicted values using the same parameters, implying changed physicochemical properties of the organic component. A sensitivity analysis suggests that a drop in surface tension must be invoked to explain quantitatively the CCN observations at low SOA particle mass loadings. Other factors, such as decreased molecular weight, increased density, or increased van't Hoff factor, can contribute to the explanation but are quantitatively insufficient as the full explanation.

A global lightning parameterization based on statistical relationships among environmental factors, aerosols, and convective clouds in the TRMM climatology

Science.gov (United States)

Stolz, Douglas C.; Rutledge, Steven A.; Pierce, Jeffrey R.; van den Heever, Susan C.

2017-07-01

The objective of this study is to determine the relative contributions of normalized convective available potential energy (NCAPE), cloud condensation nuclei (CCN) concentrations, warm cloud depth (WCD), vertical wind shear (SHEAR), and environmental relative humidity (RH) to the variability of lightning and radar reflectivity within convective features (CFs) observed by the Tropical Rainfall Measuring Mission (TRMM) satellite. Our approach incorporates multidimensional binned representations of observations of CFs and modeled thermodynamics, kinematics, and CCN as inputs to develop approximations for total lightning density (TLD) and the average height of 30 dBZ radar reflectivity (AVGHT30). The results suggest that TLD and AVGHT30 increase with increasing NCAPE, increasing CCN, decreasing WCD, increasing SHEAR, and decreasing RH. Multiple-linear approximations for lightning and radar quantities using the aforementioned predictors account for significant portions of the variance in the binned data set (R2 ≈ 0.69-0.81). The standardized weights attributed to CCN, NCAPE, and WCD are largest, the standardized weight of RH varies relative to other predictors, while the standardized weight for SHEAR is comparatively small. We investigate these statistical relationships for collections of CFs within various geographic areas and compare the aerosol (CCN) and thermodynamic (NCAPE and WCD) contributions to variations in the CF population in a partial sensitivity analysis based on multiple-linear regression approximations computed herein. A global lightning parameterization is developed; the average difference between predicted and observed TLD decreases from +21.6 to +11.6% when using a hybrid approach to combine separate approximations over continents and oceans, thus highlighting the need for regionally targeted investigations in the future.

Substantial Seasonal Contribution of Observed Biogenic Sulfate Particles to Cloud Condensation Nuclei.

Science.gov (United States)

Sanchez, Kevin J; Chen, Chia-Li; Russell, Lynn M; Betha, Raghu; Liu, Jun; Price, Derek J; Massoli, Paola; Ziemba, Luke D; Crosbie, Ewan C; Moore, Richard H; Müller, Markus; Schiller, Sven A; Wisthaler, Armin; Lee, Alex K Y; Quinn, Patricia K; Bates, Timothy S; Porter, Jack; Bell, Thomas G; Saltzman, Eric S; Vaillancourt, Robert D; Behrenfeld, Mike J

2018-02-19

Biogenic sources contribute to cloud condensation nuclei (CCN) in the clean marine atmosphere, but few measurements exist to constrain climate model simulations of their importance. The chemical composition of individual atmospheric aerosol particles showed two types of sulfate-containing particles in clean marine air masses in addition to mass-based Estimated Salt particles. Both types of sulfate particles lack combustion tracers and correlate, for some conditions, to atmospheric or seawater dimethyl sulfide (DMS) concentrations, which means their source was largely biogenic. The first type is identified as New Sulfate because their large sulfate mass fraction (63% sulfate) and association with entrainment conditions means they could have formed by nucleation in the free troposphere. The second type is Added Sulfate particles (38% sulfate), because they are preexisting particles onto which additional sulfate condensed. New Sulfate particles accounted for 31% (7 cm -3 ) and 33% (36 cm -3 ) CCN at 0.1% supersaturation in late-autumn and late-spring, respectively, whereas sea spray provided 55% (13 cm -3 ) in late-autumn but only 4% (4 cm -3 ) in late-spring. Our results show a clear seasonal difference in the marine CCN budget, which illustrates how important phytoplankton-produced DMS emissions are for CCN in the North Atlantic.

An interfacial mechanism for cloud droplet formation on organic aerosols.

Science.gov (United States)

Ruehl, Christopher R; Davies, James F; Wilson, Kevin R

2016-03-25

Accurate predictions of aerosol/cloud interactions require simple, physically accurate parameterizations of the cloud condensation nuclei (CCN) activity of aerosols. Current models assume that organic aerosol species contribute to CCN activity by lowering water activity. We measured droplet diameters at the point of CCN activation for particles composed of dicarboxylic acids or secondary organic aerosol and ammonium sulfate. Droplet activation diameters were 40 to 60% larger than predicted if the organic was assumed to be dissolved within the bulk droplet, suggesting that a new mechanism is needed to explain cloud droplet formation. A compressed film model explains how surface tension depression by interfacial organic molecules can alter the relationship between water vapor supersaturation and droplet size (i.e., the Köhler curve), leading to the larger diameters observed at activation. Copyright © 2016, American Association for the Advancement of Science.

Amazon boundary layer aerosol concentration sustained by vertical transport during rainfall

Energy Technology Data Exchange (ETDEWEB)

Wang, Jian; Krejci, Radovan; Giangrande, Scott; Kuang, Chongai; Barbosa, Henrique M. J.; Brito, Joel; Carbone, Samara; Chi, Xuguang; Comstock, Jennifer; Ditas, Florian; Lavric, Jost; Manninen, Hanna E.; Mei, Fan; Moran-Zuloaga, Daniel; Pöhlker, Christopher; Pöhlker, Mira L.; Saturno, Jorge; Schmid, Beat; Souza, Rodrigo A. F.; Springston, Stephen R.; Tomlinson, Jason M.; Toto, Tami; Walter, David; Wimmer, Daniela; Smith, James N.; Kulmala, Markku; Machado, Luiz A. T.; Artaxo, Paulo; Andreae, Meinrat O.; Petäjä, Tuukka; Martin, Scot T.

2016-10-24

A necessary prerequisite of cloud formation, aerosol particles represent one of the largest uncertainties in computer simulations of climate change1,2, in part because of a poor understanding of processes under natural conditions3,4. The Amazon rainforest is one of the few continental regions where aerosol particles and their precursors can be studied under near-natural conditions5-7. Cloud condensation nuclei (CCN) in clean Amazonia are mostly produced by the growth of smaller particles in the boundary layer8-10, whereas these smaller particles themselves 31 appear to be produced elsewhere5,11. Key questions are in what part of the atmosphere they might 32 be produced and what could be the transport processes that deliver them to the boundary layer, where they grow into CCN. Here, using recent aircraft measurements above central Amazonia, we show high concentrations of small particles in the lower free troposphere. The particle size spectrum shifts towards larger sizes with decreasing altitude, implying particle growth as air descends from the free troposphere towards Earth's surface. Complementary measurements at ground sites show that free tropospheric air having high concentrations of small particles (diameters of less than 50 nm) is transported into the boundary layer during precipitation events, both by strong convective downdrafts and by weaker downward motions in the trailing stratiform region. This vertical transport helps maintain the population of small particles and ultimately CCN in the boundary layer, thereby playing an important role in controlling the climate state under natural conditions. In contrast, this mechanism becomes masked under polluted conditions, which sometimes prevail at times in Amazonia as well as over other tropical continental regions5,12.

Evaluation of the cases of benign disease with high accumulation on the examination of [sup 18]F-fluorodeoxyglucose PET

Energy Technology Data Exchange (ETDEWEB)

Okazumi, Shinichi; Enomoto, Kazuo; Fukunaga, Toru (Chiba Univ. (Japan). School of Medicine) (and others)

1993-12-01

In this study 39 cases of abdominal benign disease were examined by PET using [sup 18]F-fluorodeoxyglucose (FDG), and 11 cases of them (i.e. 4 cases of liver abscess, 1 of pelvic abscess, 1 of omental abscess, 2 of chronic pancreatitis, 1 of inflammatory pseudotumor of liver, 1 of retroperitoneal leiomyoma and 1 of solid and cystic tumor of pancreas) which showed as high accumulation of FDG as malignant lesion were investigated of their clinical and pathological feature. We used Ci/Cp ratio as index to express the accumulation of FDG in the lesion, which was calculated from radioactivities of the lesion (Ci) and the plasma (Cp) at 60 mins after injection of FDG. The Ci/Cp ratio of the 11 cases was 3.64[+-]0.77. The pathological feature of the 9 inflammatory cases was high accumulation of inflammatory cells and that of the 2 benign tumor cases was solid proliferation of tumor cells. The serum of the 9 inflammatory cases showed high CRP value. It was considered that the high accumulation of FDG in inflammatory lesions was due to piles of FDG uptake of the many inflammatory cells, while the 2 benign tumors of high accumulation were considered that the tumor cell had as high glucose metabolism as malignancies. (author).

Potential for a biogenic influence on cloud microphysics over the ocean: a correlation study with satellite-derived data

Directory of Open Access Journals (Sweden)

A. Lana

2012-09-01

Full Text Available Aerosols have a large potential to influence climate through their effects on the microphysics and optical properties of clouds and, hence, on the Earth's radiation budget. Aerosol–cloud interactions have been intensively studied in polluted air, but the possibility that the marine biosphere plays an important role in regulating cloud brightness in the pristine oceanic atmosphere remains largely unexplored. We used 9 yr of global satellite data and ocean climatologies to derive parameterizations of the temporal variability of (a production fluxes of sulfur aerosols formed by the oxidation of the biogenic gas dimethylsulfide emitted from the sea surface; (b production fluxes of secondary organic aerosols from biogenic organic volatiles; (c emission fluxes of biogenic primary organic aerosols ejected by wind action on sea surface; and (d emission fluxes of sea salt also lifted by the wind upon bubble bursting. Series of global monthly estimates of these fluxes were correlated to series of potential cloud condensation nuclei (CCN numbers derived from satellite (MODIS. More detailed comparisons among weekly series of estimated fluxes and satellite-derived cloud droplet effective radius (r_e data were conducted at locations spread among polluted and clean regions of the oceanic atmosphere. The outcome of the statistical analysis was that positive correlation to CCN numbers and negative correlation to r_e were common at mid and high latitude for sulfur and organic secondary aerosols, indicating both might be important in seeding cloud droplet activation. Conversely, primary aerosols (organic and sea salt showed widespread positive correlations to CCN only at low latitudes. Correlations to r_e were more variable, non-significant or positive, suggesting that, despite contributing to large shares of the marine aerosol mass, primary aerosols are not widespread major drivers of the variability of cloud

Effects of biomass smoke from southern Africa on stratocumulus over southeastern Atlantic Ocean based on satellite observations and WRF-Chem model simulations

Science.gov (United States)

Lu, Z.; Liu, X.; Zhang, Z.; Zhao, C.; Meyer, K.; Rajapakshe, C.; Wu, C.; Yang, Z.; Penner, J.

2017-12-01

Each year, large amount of biomass burning (BB) aerosols are emitted over southern Africa, and transported by the predominant circulation to the southeastern Atlantic Ocean (SEA), where they overly and potentially interact with the semi-permanent stratocumulus deck in the marine boundary layer (MBL). Many previous studies suggested that the aerosol plumes are well separated from the MBL clouds, and only focused on the radiative effects of BB aerosols (direct + semi-direct radiative effects); however, as shown in several recent satellite observational studies, BB aerosols are able to be frequently entrained into the underlying clouds, function as cloud condensation nuclei (CCN), and potentially cause microphysical effects. Based on satellite observations from CATS, we found that the mixing frequencies between above-cloud aerosols and MBL clouds are very high ( 50%) over both coastal and remote regions, suggesting that BB aerosols may likely contact MBL cloud top and function as CCN quickly after they are transported over SEA. Despite the potential importance of the microphysical effect of BB aerosols over SEA, its magnitude is not fully assessed by modeling studies. In this study, we employ WRF-Chem model to study the impacts of BB aerosols on MBL stratocumulus clouds over SEA during the fire season of 2014. By designing three cases, we are able to quantitatively determine the relative importance of microphysical and radiative effects of BB aerosols. Our modeling results show that, by serving as CCN, BB aerosols are able to alter cloud properties of stratocumulus (e.g. higher cloud droplet number concentration [CDNC], higher cloud liquid water path [LWP], and larger cloud fraction [CF] before noon) and exert significant cooling effect at TOA (-8.05 Wm-2) over SEA. The cooling is primarily caused by higher CDNC (the Twomey effect), and secondarily by the changes in LWP and CF (the cloud lifetime effect). The semi-direct effect estimated in this study is smaller in

High-Throughput Computing on High-Performance Platforms: A Case Study

Energy Technology Data Exchange (ETDEWEB)

Oleynik, D [University of Texas at Arlington; Panitkin, S [Brookhaven National Laboratory (BNL); Matteo, Turilli [Rutgers University; Angius, Alessio [Rutgers University; Oral, H Sarp [ORNL; De, K [University of Texas at Arlington; Klimentov, A [Brookhaven National Laboratory (BNL); Wells, Jack C. [ORNL; Jha, S [Rutgers University

2017-10-01

The computing systems used by LHC experiments has historically consisted of the federation of hundreds to thousands of distributed resources, ranging from small to mid-size resource. In spite of the impressive scale of the existing distributed computing solutions, the federation of small to mid-size resources will be insufficient to meet projected future demands. This paper is a case study of how the ATLAS experiment has embraced Titan -- a DOE leadership facility in conjunction with traditional distributed high- throughput computing to reach sustained production scales of approximately 52M core-hours a years. The three main contributions of this paper are: (i) a critical evaluation of design and operational considerations to support the sustained, scalable and production usage of Titan; (ii) a preliminary characterization of a next generation executor for PanDA to support new workloads and advanced execution modes; and (iii) early lessons for how current and future experimental and observational systems can be integrated with production supercomputers and other platforms in a general and extensible manner.

A Case Study of a High School Fab Lab

Science.gov (United States)

Lacy, Jennifer E.

This dissertation examines making and design-based STEM education in a formal makerspace. It focuses on how the design and implementation of a Fab Lab learning environment and curriculum affect how instructors and students see themselves engaging in science, and how the Fab Lab relates to the social sorting practices that already take place at North High School. While there is research examining design-based STEM education in informal and formal learning environments, we know little about how K-12 teachers define STEM in making activities when no university or museum partnership exists. This study sought to help fill this gap in the research literature. This case study of a formal makerspace followed instructors and students in one introductory Fab Lab course for one semester. Additional observations of an introductory woodworking course helped build the case and set it into the school context, and provided supplementary material to better understand the similarities and differences between the Fab Lab course and a more traditional design-based learning course. Using evidence from observational field notes, participant interviews, course materials, and student work, I found that the North Fab Lab relies on artifacts and rhetoric symbolic of science and STEM to set itself apart from other design-based courses at North High School. Secondly, the North Fab Lab instructors and students were unable to explain how what they were doing in the Fab Lab was science, and instead relied on vague and unsupported claims related to interdisciplinary STEM practices and dated descriptions of science. Lastly, the design and implementation of the Fab Lab learning environment and curriculum and its separation from North High School's low tech, design-based courses effectively reinforced social sorting practices and cultural assumptions about student work and intelligence.

Preliminary application of the draft code case for alloy 617 for a high temperature component

International Nuclear Information System (INIS)

Lee, Hyeong Yeon; Kim, Yong Wan; Song, Kee Nam

2008-01-01

The ASME draft Code Case for Alloy 617 was developed in the late 1980s for the design of very-high-temperature gas cooled reactors. The draft Code Case was patterned after the ASME Code Section III Subsection NH and was intended to cover Ni-Cr-Co-Mo Alloy 617 to 982 .deg. C (1800 .deg. F). But the draft Code Case is still in an incomplete status, lacking necessary material properties and design data. In this study, a preliminary evaluation on the creep-fatigue damage for a high temperature hot duct pipe structure has been carried out according to the draft Code Case. The evaluation procedures and results according to the draft Code Case for Alloy 617 material were compared with those of the ASME Subsection NH and RCC-MR for Alloy 800H material. It was shown that many data including material properties, fatigue and creep data should be supplemented for the draft Code Case. However, when the evaluation results on the creep-fatigue damage according to the draft Code Case, ASME-NH and RCC-MR were compared based on the preliminary evaluation, it was shown that the Alloy 617 results from the draft Code Case tended to be more resistant to the creep damage while less resistant to the fatigue damage than those from the ASME-NH and RCC-MR

High utility of active tuberculosis case finding in an Ethiopian prison.

Science.gov (United States)

Merid, Y; Woldeamanuel, Y; Abebe, M; Datiko, D G; Hailu, T; Habtamu, G; Assefa, G; Kempker, R R; Blumberg, H M; Aseffa, A

2018-05-01

Hawassa Prison, Southern Region of Ethiopia. To determine the burden of pulmonary tuberculosis (TB) using active case finding among prisoners. In this cross-sectional study, prisoners were screened for TB using a symptom screen. Those with cough of 2 weeks had spot and morning sputum samples collected for acid-fast bacilli (AFB) smear microscopy and molecular diagnostic testing (Xpert® MTB/RIF). Among 2068 prisoners, 372 (18%) had a positive cough screen. The median age of these 372 persons was 23 years, 97% were male and 63% were from urban areas. Among those with a positive symptom screen, 8 (2%) were AFB sputum smear-positive and 31 (8%) were Xpert-positive. The point prevalence of pulmonary TB at the prison was 1748 per 100 000 persons. In multivariate analysis, persons with cough >4 weeks were more likely to have TB (OR 3.34, 95%CI 1.54-7.23). A high prevalence of TB was detected among inmates at a large Ethiopian prison. Active case finding using a cough symptom screen in combination with Xpert had high utility, and has the potential to interrupt transmission of Mycobacterium tuberculosis in correctional facilities in low- and middle-income, high-burden countries.

Multisite Case Study of Florida's Millennium High School Reform Model

Directory of Open Access Journals (Sweden)

Carol A. Mullen

2002-10-01

Full Text Available This study should have immediate utility for the United States and beyond its borders. School-to-work approaches to comprehensive reform are increasingly expected of schools while legislative funding for this purpose gets pulled back. This multisite case study launches the first analysis of the New Millennium High School (NMHS model in Florida. This improvement program relies upon exemplary leadership for preparing students for postsecondary education

Case mix-adjusted cost of colectomy at low-, middle-, and high-volume academic centers.

Science.gov (United States)

Chang, Alex L; Kim, Young; Ertel, Audrey E; Hoehn, Richard S; Wima, Koffi; Abbott, Daniel E; Shah, Shimul A

2017-05-01

Efforts to regionalize surgery based on thresholds in procedure volume may have consequences on the cost of health care delivery. This study aims to delineate the relationship between hospital volume, case mix, and variability in the cost of operative intervention using colectomy as the model. All patients undergoing colectomy (n = 90,583) at 183 academic hospitals from 2009-2012 in The University HealthSystems Consortium Database were studied. Patient and procedure details were used to generate a case mix-adjusted predictive model of total direct costs. Observed to expected costs for each center were evaluated between centers based on overall procedure volume. Patient and procedure characteristics were significantly different between volume tertiles. Observed costs at high-volume centers were less than at middle- and low-volume centers. According to our predictive model, high-volume centers cared for a less expensive case mix than middle- and low-volume centers ($12,786 vs $13,236 and $14,497, P case mix at low-volume centers, which may lead to perceived poor performance at these centers. Copyright © 2016 Elsevier Inc. All rights reserved.

Intensive case management for high-risk patients with first-episode psychosis: service model and outcomes.

Science.gov (United States)

Brewer, Warrick J; Lambert, Timothy J; Witt, Katrina; Dileo, John; Duff, Cameron; Crlenjak, Carol; McGorry, Patrick D; Murphy, Brendan P

2015-01-01

The first episode of psychosis is a crucial period when early intervention can alter the trajectory of the young person's ongoing mental health and general functioning. After an investigation into completed suicides in the Early Psychosis Prevention and Intervention Centre (EPPIC) programme, the intensive case management subprogramme was developed in 2003 to provide assertive outreach to young people having a first episode of psychosis who are at high risk owing to risk to self or others, disengagement, or suboptimal recovery. We report intensive case management model development, characterise the target cohort, and report on outcomes compared with EPPIC treatment as usual. Inclusion criteria, staff support, referral pathways, clinical review processes, models of engagement and care, and risk management protocols are described. We compared 120 consecutive referrals with 50 EPPIC treatment as usual patients (age 15-24 years) in a naturalistic stratified quasi-experimental real-world design. Key performance indicators of service use plus engagement and suicide attempts were compared between EPPIC treatment as usual and intensive case management, and psychosocial and clinical measures were compared between intensive case management referral and discharge. Referrals were predominately unemployed males with low levels of functioning and educational attainment. They were characterised by a family history of mental illness, migration and early separation, with substantial trauma, history of violence, and forensic attention. Intensive case management improved psychopathology and psychosocial outcomes in high-risk patients and reduced risk ratings, admissions, bed days, and crisis contacts. Characterisation of intensive case management patients validated the clinical research focus and identified a first episode of psychosis high-risk subgroup. In a real-world study, implementation of an intensive case management stream within a well-established first episode of psychosis

A Case of a Contraband Body Packer Requiring High-Dose Naloxone

Directory of Open Access Journals (Sweden)

Khusro Shamim

2017-09-01

Full Text Available Background:Body packers occasionally refer to the Emergency Department (ED, after leakage of package contents within intestinal lumen, resulting in life-threatening toxicities, depending upon the nature of the chemical product. Case Presentation: We present a case report of a patient presented with sudden onset of drowsiness while he was on board a flight. He was brought in by the airport security staff. On arrival to the ED, his Glasgow Coma Scale (GCS was 3/15 and pupils were pinpoint bilaterally. He was empirically treated with Naloxone on clinical suspicion of narcotic overdose. He required a cumulative dose of 12 mg of Naloxone for reversal of respiratory depression and coma. On subsequent investigation in the ED, he was identified to be a body packer. Discussion: This case represents a rare clinical example of narcotic overdose which resulted in a life-threatening opioid toxicity due to leakage of the package contents into his bowels. In this case, a dosage greater than 10 mg of the maximum recommended dose of Naloxone is required for reversal of toxicity. Conclusion:It is imperative to have a high level of suspicion for managing possible opioid intoxication as immediate treatment can be diagnostic and lifesaving. Our case required more than the recommended dosage of Naloxone, highlighting the possible suggestion of further studies to look into the maximum threshold of this reversal agent.

A national cholera epidemic with high case fatality rates--Kenya 2009.

Science.gov (United States)

Loharikar, Anagha; Briere, Elizabeth; Ope, Maurice; Langat, Daniel; Njeru, Ian; Gathigi, Lucy; Makayotto, Lyndah; Ismail, Abdirizak M; Thuranira, Martin; Abade, Ahmed; Amwayi, Samuel; Omolo, Jared; Oundo, Joe; De Cock, Kevin M; Breiman, Robert F; Ayers, Tracy; Mintz, Eric; O'Reilly, Ciara E

2013-11-01

Cholera remains endemic in sub-Saharan Africa. We characterized the 2009 cholera outbreaks in Kenya and evaluated the response. We analyzed surveillance data and estimated case fatality rates (CFRs). Households in 2 districts, East Pokot (224 cases; CFR = 11.7%) and Turkana South (1493 cases; CFR = 1.0%), were surveyed. We randomly selected 15 villages and 8 households per village in each district. Healthcare workers at 27 health facilities (HFs) were surveyed in both districts. In 2009, cholera outbreaks caused a reported 11 425 cases and 264 deaths in Kenya. Data were available from 44 districts for 6893 (60%) cases. District CFRs ranged from 0% to 14.3%. Surveyed household respondents (n = 240) were aware of cholera (97.5%) and oral rehydration solution (ORS) (87.9%). Cholera deaths were reported more frequently from East Pokot (n = 120) than Turkana South (n = 120) households (20.7% vs. 12.3%). The average travel time to a HF was 31 hours in East Pokot compared with 2 hours in Turkana South. Fewer respondents in East Pokot (9.8%) than in Turkana South (33.9%) stated that ORS was available in their village. ORS or intravenous fluid shortages occurred in 20 (76.9%) surveyed HFs. High CFRs in Kenya are related to healthcare access disparities, including availability of rehydration supplies.

Discontinuities in hygroscopic growth below and above water saturation for laboratory surrogates of oligomers in organic atmospheric aerosols

Directory of Open Access Journals (Sweden)

N. Hodas

2016-10-01

supersaturation of 0.8 %. We also observed a marked increase in apparent hygroscopicity for mixtures of higher molecular mass PEG and AS under supersaturated conditions as compared to subsaturated hygroscopic growth. AIOMFAC-based predictions and estimations of water diffusivity in PEG suggest that such discontinuities in apparent hygroscopicity above and below water saturation can be attributed, at least in part, to differences in the sensitivity of water uptake behavior to surface tension effects. There is no evidence that kinetic limitations to water uptake due to the presence of viscous aerosol components influenced hygroscopic growth. For the systems that display an enhancement in apparent hygroscopicity above water saturation, LLPS is predicted to persist to high RH. This indicates a miscibility gap and is likely to influence bulk-to-surface partitioning of PEG at high RH, impacting droplet surface tension and CCN activity. This work provides insight into the factors likely to be contributing to discontinuities in aerosol water-uptake behavior below and above water saturation that have been observed previously in the ambient atmosphere.

A Case of Esophageal Leiomyoma Showing High FDG Uptake on F-18 FDG PET

Energy Technology Data Exchange (ETDEWEB)

Lee, Jai Hyuen [College of Medicine, Cheonan (Korea, Republic of); Ryu, Jin Sook [Asan Medical Center, University of Ulsan College of Medicine (Korea, Republic of)

2008-08-15

An esophageal leiomyoma is the most common benign tumor of the esophagus mainly occurred in intramural portion. Occasionally, it is difficult to discriminate esophageal malignancy from large leiomyoma. Although F-18 FDG PET has been used for differentiating malignant from benign disease, false-positive cases have been reported. Recently, uterine leiomyoma has been reported to have relatively high F-18 FDG uptake in some patients but little is known about how an esophageal leiomyoma might be showed on F-18 FDG PET. We report a case of esophageal leiomyoma that showed high FDG uptake on PET images.

A Case of Esophageal Leiomyoma Showing High FDG Uptake on F-18 FDG PET

International Nuclear Information System (INIS)

Lee, Jai Hyuen; Ryu, Jin Sook

2008-01-01

An esophageal leiomyoma is the most common benign tumor of the esophagus mainly occurred in intramural portion. Occasionally, it is difficult to discriminate esophageal malignancy from large leiomyoma. Although F-18 FDG PET has been used for differentiating malignant from benign disease, false-positive cases have been reported. Recently, uterine leiomyoma has been reported to have relatively high F-18 FDG uptake in some patients but little is known about how an esophageal leiomyoma might be showed on F-18 FDG PET. We report a case of esophageal leiomyoma that showed high FDG uptake on PET images

Fiber Reinforced Concrete (FRC) for High Rise Construction: Case Studies

Science.gov (United States)

Gharehbaghi, Koorosh; Chenery, Rhea

2017-12-01

Due to its material element, Fiber Reinforced Concrete (FRC) could be stronger than traditional Concrete. This is due to FRC internal material compounds and elements. Furthermore, FRC can also significantly improve flexural strength when compared to traditional Concrete. This improvement in flexural strength can be varied depending on the actual fibers used. Although not new, FRC is gradually gaining popularity in the construction industry, in particular for high rise structures. This is due to its flexural strength, especially for high seismic zones, as it will provide a better solution then reinforced Concrete. The main aim of this paper is to investigate the structural importance of FRC for the high rise construction. Although there has been numerous studies and literature in justifying the FRC for general construction; this paper will consider its use specifically for high rise construction. Moreover, this paper will closely investigate eight case studies from Australian and United States as a part of the FRC validation for high rise construction. In doing so, this paper will examine their Structural Health Monitoring (SHM) to determine their overall structural performance.

Uncovering highly obfuscated plagiarism cases using fuzzy semantic-based similarity model

Directory of Open Access Journals (Sweden)

Salha M. Alzahrani

2015-07-01

Full Text Available Highly obfuscated plagiarism cases contain unseen and obfuscated texts, which pose difficulties when using existing plagiarism detection methods. A fuzzy semantic-based similarity model for uncovering obfuscated plagiarism is presented and compared with five state-of-the-art baselines. Semantic relatedness between words is studied based on the part-of-speech (POS tags and WordNet-based similarity measures. Fuzzy-based rules are introduced to assess the semantic distance between source and suspicious texts of short lengths, which implement the semantic relatedness between words as a membership function to a fuzzy set. In order to minimize the number of false positives and false negatives, a learning method that combines a permission threshold and a variation threshold is used to decide true plagiarism cases. The proposed model and the baselines are evaluated on 99,033 ground-truth annotated cases extracted from different datasets, including 11,621 (11.7% handmade paraphrases, 54,815 (55.4% artificial plagiarism cases, and 32,578 (32.9% plagiarism-free cases. We conduct extensive experimental verifications, including the study of the effects of different segmentations schemes and parameter settings. Results are assessed using precision, recall, F-measure and granularity on stratified 10-fold cross-validation data. The statistical analysis using paired t-tests shows that the proposed approach is statistically significant in comparison with the baselines, which demonstrates the competence of fuzzy semantic-based model to detect plagiarism cases beyond the literal plagiarism. Additionally, the analysis of variance (ANOVA statistical test shows the effectiveness of different segmentation schemes used with the proposed approach.

Analysis of cloud condensation nuclei composition and growth kinetics using a pumped counterflow virtual impactor and aerosol mass spectrometer

Directory of Open Access Journals (Sweden)

J. G. Slowik

2011-08-01

Full Text Available We present a new method of determining the size and composition of CCN-active aerosol particles. Method utility is illustrated through a series of ambient measurements. A continuous-flow thermal-gradient diffusion chamber (TGDC, pumped counterflow virtual impactor (PCVI, and Aerodyne time-of-flight mass spectrometer (AMS are operated in series. Ambient particles are sampled into the TGDC, where a constant supersaturation is maintained, and CCN-active particles grow to ~2.5 ± 0.5 μm. The output flow from the TGDC is directed into the PCVI, where a counterflow of dry N₂ gas opposes the particle-laden flow, creating a region of zero axial velocity. This stagnation plane can only be traversed by particles with sufficient momentum, which depends on their size. Particles that have activated in the TGDC cross the stagnation plane and are entrained in the PCVI output flow, while the unactivated particles are diverted to a pump. Because the input gas is replaced by the counterflow gas with better than 99 % efficiency at the stagnation plane, the output flow consists almost entirely of dry N₂ and water evaporates from the activated particles. In this way, the system yields an ensemble of CCN-active particles whose chemical composition and size are analyzed using the AMS. Measurements of urban aerosol in downtown Toronto identified an external mixture of CCN-active particles consisting almost entirely of ammonium nitrate and ammonium sulfate, with CCN-inactive particles of the same size consisting of a mixture of ammonium nitrate, ammonium sulfate, and organics. We also discuss results from the first field deployment of the TGDC-PCVI-AMS system, conducted from mid-May to mid-June 2007 in Egbert, Ontario, a semirural site ~80 km north of Toronto influenced both by clean air masses from the north and emissions from the city. Organic-dominated particles sampled during a major biogenic event exhibited higher CCN activity and/or faster

Welding repair of the high-intermediate pressure steam casings made of Cr-Mo and Cr-Mo-V steel

International Nuclear Information System (INIS)

Mazur, Z.; Cristalinas, V.; Kubiak, J.

1996-01-01

An analysis of typical failure causes and their location at high-intermediate pressure steam turbine casing, and weldability analysis of the Cr-Mo and Cr-Mo-V steels, is carried out. basing on the steam turbine of 158 MW capacity, the internal high pressure casing failures and development of in situ repair welding technology is described. After repair, the casing was put back into service

Synthesis and optical properties of enantiomeric cinchonidine/cinchonine-terpyridine derivatives and their metal complexes

International Nuclear Information System (INIS)

Wang, Hui-Ting; Wu, Wen-Jie; Liu, Jiang; Chen, Meng; Qian, Dong-Jin; Zhang, Li; Liu, Minghua

2016-01-01

We report here the synthesis and spectroscopic properties of two enantiomeric chiral tridentate ligands (TPyCCD and TPyCCN) composed of terpyridine (TPy) and cinchonidine (CCD) or cinchonine (CCN) substituent, as well as their metal complexes with Zn 2+ , Fe 2+ , Eu 3+ , and Tb 3+ ions. For the pure ligands, the fluorescent emission intensity increased as their concentrations increased in the dilute solutions, but they decreased when the concentrations were greater than 6.9×10 −6 mol/l due to concentration quenching. No significant influence on ligand luminescence was observed for the Zn 2+ /Fe 2+ –TPyCCD and –TPyCCN metal complexes. Their lanthanide (Eu 3+ and Tb 3+ ) complexes displayed both ligand and lanthanide ion emissions, suggesting that the excited energy of both ligands could be transferred to the central Eu 3+ and Tb 3+ ions. Mirror-image circular dichroism spectra were recorded, with several signals centered at about 230, 250–270, 296, and 320 nm; the first ones corresponded to the chiral CCD and CCN substituents, while the latter ones corresponded to the TPy substituent and the metal–TPy (M-TPy) coordination units. It is suggested that the chirality of TPy and the metal complexes was induced by the coexisting chiral CCD and CCN substituents. In addition, due to formation of the metal complexes, the relative intensity of the chiral signals of M–TPy coordination units was enhanced at about 320 nm. - Highlights: • Cinchona alkaloid-terpyridine derivatives and metal complexes were prepared. • Cinchona alkaloid-terpyridine derivatives gave off luminescence at 362 nm. • Ligand excited energy could efficiently transferred to lanthanide ions. • Chirality of terpyridine and metal complexes was induced.

Cloud Condensation Nuclei Measurements During the First Year of the ORACLES Study

Science.gov (United States)

Kacarab, M.; Howell, S. G.; Wood, R.; Redemann, J.; Nenes, A.

2016-12-01

Aerosols have significant impacts on air quality and climate. Their ability to scatter and absorb radiation and to act as cloud condensation nuclei (CCN) plays a very important role in the global climate. Biomass burning organic aerosol (BBOA) can drastically elevate the concentration of CCN in clouds, but the response in droplet number may be strongly suppressed (or even reversed) owing to low supersaturations that may develop from the strong competition of water vapor (Bougiatioti et al. 2016). Understanding and constraining the magnitude of droplet response to biomass burning plumes is an important component of the aerosol-cloud interaction problem. The southeastern Atlantic (SEA) cloud deck provides a unique opportunity to study these cloud-BBOA interactions for marine stratocumulus, as it is overlain by a large, optically thick biomass burning aerosol plume from Southern Africa during the burning season. The interaction between these biomass burning aerosols and the SEA cloud deck is being investigated in the NASA ObseRvations of Aerosols above Clouds and their intEractionS (ORACLES) study. The CCN activity of aerosol around the SEA cloud deck and associated biomass burning plume was evaluated during the first year of the ORACLES study with direct measurements of CCN concentration, aerosol size distribution and composition onboard the NASA P-3 aircraft during August and September of 2016. Here we present analysis of the observed CCN activity of the BBOA aerosol in and around the SEA cloud deck and its relationship to aerosol size, chemical composition, and plume mixing and aging. We also evaluate the predicted and observed droplet number sensitivity to the aerosol fluctuations and quantify, using the data, the drivers of droplet number variability (vertical velocity or aerosol properties) as a function of biomass burning plume characteristics.

Developing High PV Penetration Cases for Frequency Response Study of U.S. Western Interconnection: Preprint

Energy Technology Data Exchange (ETDEWEB)

Tan, Jin; Zhang, Yingchen; Veda, Santosh; Elgindy, Tarek; Liu, Yilu

2017-04-11

Recent large penetrations of solar photovoltaic (PV) generation and the inertial characteristics of inverter-based generation technologies have caught the attention of those in the electric power industry in the United States. This paper presents a systematic approach to developing test cases of high penetrations of PV for the Western Interconnection. First, to examine the accuracy of the base case model, the Western Electricity Coordinating Council (WECC) model is validated by using measurement data from synchronized phasor measurement units. Based on the 2022 Light Spring case, we developed four high PV penetration cases for the WECC system that are of interest to the industry: 5% PV+15 % wind, 25% PV+15% wind, 45% PV+15% wind, 65% PV+15% wind). Additionally, a method to project PV is proposed that is based on collected, realistic PV distribution information, including the current and future PV power plant locations and penetrations in the WECC system. Both the utility-scale PV plant and residential rooftop PV are included in this study.

Air pollution control and decreasing new particle formation lead to strong climate warming

OpenAIRE

Makkonen, R.; Asmi, A.; Kerminen, V.-M.; Boy, M.; Arneth, A.; Hari, P.; Kulmala, M.

2012-01-01

The number concentration of cloud droplets determines several climatically relevant cloud properties. A major cause for the high uncertainty in the indirect aerosol forcing is the availability of cloud condensation nuclei (CCN), which in turn is highly sensitive to atmospheric new particle formation. Here we present the effect of new particle formation on anthropogenic aerosol forcing in present-day (year 2000) and future (year 2100) conditions. The present-day total aerosol forcing is increa...

[Asperger syndrome with highly exceptional calendar memory: a case report].

Science.gov (United States)

Sevik, Ali Emre; Cengel Kültür, Ebru; Demirel, Hilal; Karlı Oğuz, Kader; Akça, Onur; Lay Ergün, Eser; Demir, Başaran

2010-01-01

Some patients with pervasive developmental disorders develop unusual talents, which are characterized as savant syndrome. Herein we present neuropsychological examination and brain imaging (fMRI and brain SPECT) findings of an 18-year-old male with Asperger syndrome and highly unusual calendar memory. Neuropsychological evaluation of the case indicated mild attention, memory, and problem solving deficits, and severe executive function deficits that included conceptualization, category formation, and abstraction. Functional MRI findings showed activation above the baseline level (Psavant syndrome.

Flow visualization of bubble behavior under two-phase natural circulation flow conditions using high speed digital camera

Energy Technology Data Exchange (ETDEWEB)

Lemos, Wanderley F.; Su, Jian, E-mail: wlemos@con.ufrj.br, E-mail: sujian@lasme.coppe.ufrj.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Faccini, Jose L.H., E-mail: faccini@ien.gov.br [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Lab. de Termo-Hidraulica Experimental

2013-07-01

The The present work aims at identifying flow patterns and measuring interfacial parameters in two-phase natural circulation by using visualization technique with high-speed digital camera. The experiments were conducted in the Natural Circulation Circuit (CCN), installed at Nuclear Engineering Institute/CNEN. The thermo-hydraulic circuit comprises heater, heat exchanger, expansion tank, the pressure relief valve and pipes to interconnect the components. A glass tube is installed at the midpoint of the riser connected to the heater outlet. The natural circulation circuit is complemented by acquisition system of values of temperatures, flow and graphic interface. The instrumentation has thermocouples, volumetric flow meter, rotameter and high-speed digital camera. The experimental study is performed through analysis of information from measurements of temperatures at strategic points along the hydraulic circuit, besides natural circulation flow rates. The comparisons between analytical and experimental values are validated by viewing, recording and processing of the images for the flows patterns. Variables involved in the process of identification of flow regimes, dimensionless parameters, the phase velocity of the flow, initial boiling point, the phenomenon of 'flashing' pre-slug flow type were obtained experimentally. (author)

Flow visualization of bubble behavior under two-phase natural circulation flow conditions using high speed digital camera

International Nuclear Information System (INIS)

Lemos, Wanderley F.; Su, Jian; Faccini, Jose L.H.

2013-01-01

The The present work aims at identifying flow patterns and measuring interfacial parameters in two-phase natural circulation by using visualization technique with high-speed digital camera. The experiments were conducted in the Natural Circulation Circuit (CCN), installed at Nuclear Engineering Institute/CNEN. The thermo-hydraulic circuit comprises heater, heat exchanger, expansion tank, the pressure relief valve and pipes to interconnect the components. A glass tube is installed at the midpoint of the riser connected to the heater outlet. The natural circulation circuit is complemented by acquisition system of values of temperatures, flow and graphic interface. The instrumentation has thermocouples, volumetric flow meter, rotameter and high-speed digital camera. The experimental study is performed through analysis of information from measurements of temperatures at strategic points along the hydraulic circuit, besides natural circulation flow rates. The comparisons between analytical and experimental values are validated by viewing, recording and processing of the images for the flows patterns. Variables involved in the process of identification of flow regimes, dimensionless parameters, the phase velocity of the flow, initial boiling point, the phenomenon of 'flashing' pre-slug flow type were obtained experimentally. (author)

INFLUENCE OF MARKETING COMMUNICATIVE STRATEGIES ON CONSUMER BEHAVIOUR: A CASE OF THE HIGH-TECHNOLOGY MARKET OF UKRAINE

Directory of Open Access Journals (Sweden)

Victoria Zhurylo

2017-11-01

Full Text Available The purpose of the study is to research consumer behaviour types and to develop marketing strategies of communicative influence on the consumer in the high-technology goods market. Methodology. Marketing research in Ukrainian market of high-tech goods is conducted to define motivations of the consumers and the peculiarities of their market behaviour. The profiles of target customers are developed and the typology of consumer behaviour is formed, based on the reasons of purchasing of high-tech goods and on the level of consumer involvement in the purchasing process. Results showed that Highly Rational, Cautious, and Demonstrative behaviours can be observed in case of high consumer involvement in the buying process. Rationally-Confident, Comfortable, Adaptive behaviour can be observed in the case of low involvement. The peculiarities of communicative influence for each type of consumer behaviour in the market of high-tech goods are determined and the appropriate strategies of marketing communication are offered. Practical implementation. Strategies of communicative influence and communication sources depend on consumer behavioural types and the stage of the process of adopting innovations. In case of highly rational consumer behaviour, generic strategy, benefit strategy, and unique technical advantage strategies are recommended to be used as the main communicative strategies. Benefit strategy, unique technical advantage strategy, positioning strategy should be used in the case of rationally confident behaviour. The technology of intrusion, intimidation, positioning strategy, affective strategy, and resonance strategy should be used in the case of cautious consumer behaviour. Brand strategy should be used in the case of demonstrative consumer behaviour. The communicative strategies of product positioning and the strategy of resonance can be used in the case of comfortable consumer behaviour. Brand strategy is the main communicative strategy in the

HIGH ORIGIN OF SUPERFICIAL ULNAR ARTERY- A CASE REPORT

Directory of Open Access Journals (Sweden)

Anjana Jayakumaran Nair

2017-03-01

Full Text Available BACKGROUND High origin and superficially placed ulnar artery is a rare anatomical variant that usually arises either in the axilla or arm and runs a superficial course in the forearm, enters the hand and participates in the formation of superficial palmar arch. During routine dissection of cadavers in our department, we observed a unilateral case of high origin and superficial ulnar artery in a human male cadaver. It originated from the brachial artery in the lower third of arm 4 cm above its bifurcation. From its origin, it passed downwards along the medial aspect of forearm, superficial to the flexors, entered hand superficial to the flexor retinaculum and formed superficial palmar arch. The knowledge of existence of a superficial ulnar artery is important during vascular and reconstructive surgery and also in evaluation of angiographic images. Superficial position makes it more vulnerable to trauma and more accessible to cannulation.

Anthropogenic contribution to cloud condensation nuclei and the first aerosol indirect climate effect

International Nuclear Information System (INIS)

Yu Fangqun; Ma Xiaoyan; Luo Gan

2013-01-01

Atmospheric particles influence the climate indirectly by acting as cloud condensation nuclei (CCN). The first aerosol indirect radiative forcing (FAIRF) constitutes the largest uncertainty among the radiative forcings quantified by the latest IPCC report (IPCC2007) and is a major source of uncertainty in predicting climate change. Here, we investigate the anthropogenic contribution to CCN and associated FAIRF using a state-of-the-art global chemical transport and aerosol model (GEOS-Chem/APM) that contains a number of advanced features (including sectional particle microphysics, online comprehensive chemistry, consideration of all major aerosol species, online aerosol–cloud–radiation calculation, and usage of more accurate assimilated meteorology). The model captures the absolute values and spatial distributions of CCN concentrations measured in situ around the globe. We show that anthropogenic emissions increase the global mean CCN in the lower troposphere by ∼60–80% and cloud droplet number concentration by ∼40%. The global mean FAIRF based on GEOS-Chem/APM is −0.75 W m −2 , close to the median values of both IPCC2007 and post-IPCC2007 studies. To the best of our knowledge, this is the first time that a global sectional aerosol model with full online chemistry and considering all major aerosol species (including nitrate, ammonium, and second organic aerosols) has been used used to calculate FAIRF. (letter)

Social exclusion and high speed rail: The case study of Spain

Energy Technology Data Exchange (ETDEWEB)

Pagliara, F.; Menicocci, F.; Vassallo, J.M.; Gomez, J.

2016-07-01

Very few contributions in the literature have dealt with the issue of social exclusion related to High Speed Rail systems. The objective of this manuscript is to understand what are the factors excluding users from choosing High Speed Rail services considering as case study Spain. For this purpose, a Revealed Preference survey was employed in November and December 2015. A questionnaire was submitted to users of the Spanish transport systems travelling for long distance-journeys. The aim was that of investigating their perception of High Speed Rail system and the factors inhibiting passengers or excluding them from its use. Data about their socioeconomic characteristics were collected as well. The main result of the survey has been that a relationship between social exclusion and High Speed Rail in Spain is present, especially in terms of geographical exclusion. (Author)

High Origin of Radial Arteries: A Report of Two Rare Cases

Directory of Open Access Journals (Sweden)

Dong Zhan

2010-01-01

Full Text Available Variations in the arterial supply of the upper limb are relatively common, with reported prevalence rates ranging from 11 to 24.4%. Of these, the most commonly encountered variation in the arm is a high origin of the radial artery. However, after consecutively dissecting and examining 600 Singaporean Chinese cadavers (1,200 upper limbs, we found only two cases of this. In both cases, the brachioradial artery originated from the upper one-third of the brachial artery and continued distally as the radial artery in the forearm. The local prevalence of 0.33% of this variation is significantly lower compared against populations from other geographical regions. Although rare, recognition of the variation is of fundamental importance to clinical practice.

Aplicación del paradigma de redes centradas en contenido a redes de sensores

OpenAIRE

Carrillo Sánchez, David

2013-01-01

El presente trabajo de fin de grado va a exponer los fundamentos de un nuevo paradigma de comunicaciones en red, CCN (Content Centric Networking), una reciente propuesta alternativa al modelo TCP/IP actual. Dicho paradigma de comunicaciones se caracteriza por basar sus operaciones de comunicación en los propios nombres de los contenidos, abstrayéndose del concepto de localización de los contenidos. Es decir en CCN pedimos un contenido identificándolo por su nombre, en contraposici...

Acquiring skills in malignant hyperthermia crisis management: comparison of high-fidelity simulation versus computer-based case study

Directory of Open Access Journals (Sweden)

Vilma Mejía

Full Text Available Abstract Introduction: The primary purpose of this study was to compare the effect of high fidelity simulation versus a computer-based case solving self-study, in skills acquisition about malignant hyperthermia on first year anesthesiology residents. Methods: After institutional ethical committee approval, 31 first year anesthesiology residents were enrolled in this prospective randomized single-blinded study. Participants were randomized to either a High Fidelity Simulation Scenario or a computer-based Case Study about malignant hyperthermia. After the intervention, all subjects' performance in was assessed through a high fidelity simulation scenario using a previously validated assessment rubric. Additionally, knowledge tests and a satisfaction survey were applied. Finally, a semi-structured interview was done to assess self-perception of reasoning process and decision-making. Results: 28 first year residents finished successfully the study. Resident's management skill scores were globally higher in High Fidelity Simulation versus Case Study, however they were significant in 4 of the 8 performance rubric elements: recognize signs and symptoms (p = 0.025, prioritization of initial actions of management (p = 0.003, recognize complications (p = 0.025 and communication (p = 0.025. Average scores from pre- and post-test knowledge questionnaires improved from 74% to 85% in the High Fidelity Simulation group, and decreased from 78% to 75% in the Case Study group (p = 0.032. Regarding the qualitative analysis, there was no difference in factors influencing the student's process of reasoning and decision-making with both teaching strategies. Conclusion: Simulation-based training with a malignant hyperthermia high-fidelity scenario was superior to computer-based case study, improving knowledge and skills in malignant hyperthermia crisis management, with a very good satisfaction level in anesthesia residents.

Thermodynamic properties and cloud droplet activation of a series of oxo-acids

Directory of Open Access Journals (Sweden)

M. Frosch

2010-07-01

Full Text Available We have investigated the thermodynamic properties of four aliphatic oxo-dicarboyxlic acids identified or thought to be present in atmospheric particulate matter: oxosuccinic acid, 2-oxoglutaric acid, 3-oxoglutaric acid, and 4-oxopimelic acid. The compounds were characterized in terms of their cloud condensation nuclei (CCN activity, vapor pressure, density, and tendency to decarboxylate in aqueous solution. We deployed a variety of experimental techniques and instruments: a CCN counter, a Tandem Differential Mobililty Analyzer (TDMA coupled with a laminar flow-tube, and liquid chromatography/mass spectrometry (LC/MS. The presence of the oxo functional group in the α-position causes the vapor pressure of the compounds to diminish by an order of magnitude with respect to the parent dicarboxylic acid, while the CCN activity is similar or increased. Dicarboxylic acids with an oxo-group in the β-position decarboxylate in aqueous solution. We studied the effects of this process on our measurements and findings.

High risk human papillomavirus in the periodontium : A case control study.

Science.gov (United States)

Shipilova, Anna; Dayakar, Manjunath Mundoor; Gupta, Dinesh

2017-01-01

Human papilloma viruses (HPVs) are small DNA viruses that have been identified in periodontal pocket as well as gingival sulcus. High risk HPVs are also associated with a subset of head and neck carcinomas. It is thought that the periodontium could be a reservoir for HPV. 1. Detection of Human Papilloma virus (HPV) in periodontal pocket as well as gingival of patients having localized chronic periodontitis and gingival sulcus of periodontally healthy subjects. 2. Quantitative estimation of E6 and E7 mRNA in subjects showing presence of HPV3. To assess whether periodontal pocket is a reservoir for HPV. This case-control study included 30 subjects with localized chronic Periodontitis (cases) and 30 periodontally healthy subjects (controls). Two samples were taken from cases, one from periodontal pocket and one from gingival sulcus and one sample was taken from controls. Samples were collected in the form of pocket scrapings and gingival sulcus scrapings from cases and controls respectively. These samples were sent in storage media for identification and estimation of E6/E7 mRNA of HPV using in situ hybridization and flow cytometry. Statistical analysis was done by using, mean, percentage and Chi Square test. A statistical package SPSS version 13.0 was used to analyze the data. P value oral cancer, periodontitis and HPV. However prospective studies are required to further explore this link.

High-dose zolpidem dependence - Psychostimulant effects? A case report and literature review

Directory of Open Access Journals (Sweden)

Abhijna Chandan Chattopadhyay

2016-01-01

Full Text Available Zolpidem, an imidazoline nonbenzodiazepine sedative drug, is used widely. Initial reports showed minimal abuse potential. However, multiple reports have appeared of dose escalation and abuse. Subjective effects of high-dose zolpidem are not known. In light of accumulating evidence of abuse potential, we hereby report a case of high-dose dependence and a review of relevant literature. A 33-year-old male presented with 5 years of daily use of 600–1700 mg of zolpidem tartrate. He reported subjective effects of euphoria, intense craving, and inability to stop use. Loss of receptor specificity, pharmacokinetic factors, and different receptor distributions can explain paradoxical stimulatory effects of high-dose zolpidem. Further studies are required to characterize subjective effects of high-dose zolpidem.

[Acquiring skills in malignant hyperthermia crisis management: comparison of high-fidelity simulation versus computer-based case study].

Science.gov (United States)

Mejía, Vilma; Gonzalez, Carlos; Delfino, Alejandro E; Altermatt, Fernando R; Corvetto, Marcia A

The primary purpose of this study was to compare the effect of high fidelity simulation versus a computer-based case solving self-study, in skills acquisition about malignant hyperthermia on first year anesthesiology residents. After institutional ethical committee approval, 31 first year anesthesiology residents were enrolled in this prospective randomized single-blinded study. Participants were randomized to either a High Fidelity Simulation Scenario or a computer-based Case Study about malignant hyperthermia. After the intervention, all subjects' performance in was assessed through a high fidelity simulation scenario using a previously validated assessment rubric. Additionally, knowledge tests and a satisfaction survey were applied. Finally, a semi-structured interview was done to assess self-perception of reasoning process and decision-making. 28 first year residents finished successfully the study. Resident's management skill scores were globally higher in High Fidelity Simulation versus Case Study, however they were significant in 4 of the 8 performance rubric elements: recognize signs and symptoms (p = 0.025), prioritization of initial actions of management (p = 0.003), recognize complications (p = 0.025) and communication (p = 0.025). Average scores from pre- and post-test knowledge questionnaires improved from 74% to 85% in the High Fidelity Simulation group, and decreased from 78% to 75% in the Case Study group (p = 0.032). Regarding the qualitative analysis, there was no difference in factors influencing the student's process of reasoning and decision-making with both teaching strategies. Simulation-based training with a malignant hyperthermia high-fidelity scenario was superior to computer-based case study, improving knowledge and skills in malignant hyperthermia crisis management, with a very good satisfaction level in anesthesia residents. Copyright © 2018 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights

Enhancement of catalytic activity of enzymes by heating in anhydrous organic solvents: 3D structure of a modified serine proteinase at high resolution.

Science.gov (United States)

Sharma, S; Tyagi, R; Gupta, M N; Singh, T P

2001-01-01

For the first time, it is demonstrated that exposure of an enzyme to anhydrous organic solvents at optimized high temperature enhances its catalytic power through local changes at the binding region. Six enzymes, namely, proteinase K, wheat germ acid phosphatase, alpha-amylase, beta-glucosidase, chymotrypsin and trypsin were exposed to acetonitrile at 70 degrees C for three hr. The activities of these enzymes were found to be considerably enhanced. In order to understand the basis of this change in the activity of these enzymes, proteinase K was analyzed in detail using X-ray diffraction method. The overall structure of the enzyme was found to be similar to the native structure in aqueous environment. The hydrogen bonding system of the catalytic triad remained intact after the treatment. However, the water structure in the substrate binding site underwent some rearrangement as some of the water molecules were either displaced or completely absent. The most striking observation concerning the water structure was the complete deletion of the water molecule which occupied the position at the so-called oxyanion hole in the active site of the native enzyme. Three acetonitrile molecules were found in the present structure. All the acetonitrile molecules were located in the recognition site. Interlinked through water molecules, the sites occupied by acetonitrile molecules were independent of water molecules. The acetonitrile molecules are involved in extensive interactions with the protein atoms. The methyl group of one of the acetonitrile molecules (CCN1) interacts simultaneously with the hydrophobic side chains of Leu 96, Ile 107 and Leu 133. The development of such a hydrophobic environment at the recognition site introduced a striking conformation change in Ile 107 by rotating its side chain about C alpha-C beta bond by 180 degrees to bring about the delta-methyl group within the range of attractive van der Waals interactions with the methyl group of CCN1. A similar

Surgical protocol for confirmed or suspected cases of Ebola and other highly transmissible diseases.

Science.gov (United States)

Badia, Josep M; Rubio-Pérez, Inés; Arias Díaz, Javier; Guirao Garriga, Xavier; Serrablo, Alejandro; Jover Navalón, José M

2016-01-01

Outbreaks of viral haemorrhagic fevers such as Ebola can lead to imported cases in Europe and America. The eventuality of surgery in the setting of Ebola Virus Disease (EVD) is low, but the Spanish Association of Surgeons elaborated a surgical protocol for EVD. Elective surgical procedures are not indicated. Emergency cases can be considered in: persons under investigation, possible cases and early confirmed cases. In some conditions usually treated by surgery a medical treatment can be tested. All cases must be treated in high technology hospitals. These hospitals must be equipped with adequate means for healthcare provider's protection. All members of the healthcare team should practice thorough simulation prior to caring for a possible Ebola patient. This protocol is based on international guidelines on use of Personal Protective Equipment, protocols of other scientific societies, and specific recommendations for the operating room environment. Copyright © 2015 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.

Evaluation of 19 cases of benign lesions with high accumulation of tracer on 18F-FDG PET imaging

International Nuclear Information System (INIS)

Wang Quanshi; Wu Hubing; Wang Mingfang; Huang Zuhan

2003-01-01

Objective: To review PET images of benign lesions with high accumulation of 18 F-FDG and to analyse the possibility of FDG PET imaging for differentiating the benign from the malignant. Methods: 18 F-FDG PET imaging was performed on 19 patients with benign diseases including 13 cases of active tuberculosis and 6 cases of other benign diseases. Positive pathologic or bacteriological results were obtained for all the patients. PET images were evaluated with standardized uptake value (SUV), lesion shapes , and radioactivity distribution. CT or MRI and histopathologic findings also were reviewed. Results: 1) Thirteen patients with active tuberculosis showed high uptake of 18 F-FDG. The SUV was 3.1±1.8. But radioactivity distribution in some lesions was not uniform and there were defect areas in the lesions. Histopathologic findings proved that the defect areas were induced by caseous necrosis. Seven cases of pulmonary tuberculosis showed two or multiple stripe and funicular high accumulation and other lesions displayed high uptake in sheet or irregular shape; 1 case of scrofula and 1 case of splenetic tuberculosis showed defect areas in the lesions; the other scrofula case showed focal intense uptake. Two of lumbar tuberculosis showed intense uptake in the lumbar vertebra, and one of the two cases complicated with the cold abscess showed bilateral high accumulation in the shape of sheet along musculus psoas major. In the peritoneal tuberculosis case, PET images showed diffuse incrassation and intense uptake in peritoneum and mesentery. CT findings revealed that the peritoneum and mesentery thickened. 2) Pulmonary abscess, pulmonary cryptococcus granuloma, cerebral cryptococcus granuloma, pulmonary inflammatory pseudotumor, leiomyoma, and breast adenoma all showed high accumulation in the shapes of nodule or mass. Mean SUV was 4.5±3.1. CT or MRI findings were the same as on PET images shape. Histopathologic work-up did not find necrosis in the lesions. Conclusions

Individual aerosol particles in ambient and updraft conditions below convective cloud bases in the Oman mountain region

Science.gov (United States)

Semeniuk, T. A.; Bruintjes, R. T.; Salazar, V.; Breed, D. W.; Jensen, T. L.; Buseck, P. R.

2014-03-01

An airborne study of cloud microphysics provided an opportunity to collect aerosol particles in ambient and updraft conditions of natural convection systems for transmission electron microscopy (TEM). Particles were collected simultaneously on lacey carbon and calcium-coated carbon (Ca-C) TEM grids, providing information on particle morphology and chemistry and a unique record of the particle's physical state on impact. In total, 22 particle categories were identified, including single, coated, aggregate, and droplet types. The fine fraction comprised up to 90% mixed cation sulfate (MCS) droplets, while the coarse fraction comprised up to 80% mineral-containing aggregates. Insoluble (dry), partially soluble (wet), and fully soluble particles (droplets) were recorded on Ca-C grids. Dry particles were typically silicate grains; wet particles were mineral aggregates with chloride, nitrate, or sulfate components; and droplets were mainly aqueous NaCl and MCS. Higher numbers of droplets were present in updrafts (80% relative humidity (RH)) compared with ambient conditions (60% RH), and almost all particles activated at cloud base (100% RH). Greatest changes in size and shape were observed in NaCl-containing aggregates (>0.3 µm diameter) along updraft trajectories. Their abundance was associated with high numbers of cloud condensation nuclei (CCN) and cloud droplets, as well as large droplet sizes in updrafts. Thus, compositional dependence was observed in activation behavior recorded for coarse and fine fractions. Soluble salts from local pollution and natural sources clearly affected aerosol-cloud interactions, enhancing the spectrum of particles forming CCN and by forming giant CCN from aggregates, thus, making cloud seeding with hygroscopic flares ineffective in this region.

Scaphoid Stress Fracture in High-Level Gymnast: A Case Report

Directory of Open Access Journals (Sweden)

J. C. Nakamoto

2011-01-01

Full Text Available We present the case of an 18-year-old high-level gymnast who sustained a stress fracture of the scaphoid associated with a distal radial epiphysiolysis. Clinical evaluation demonstrated decreased range of motion of the affected wrist and insidious pain on the snuffbox and tenderness on the distal radial physis. He was submitted to surgical treatment with scaphoid percutaneous fixation and radial styloid process in situ fixation. Clinical features improved, and he got back to competition 6 months after surgery without symptoms and with complete range of motion.

Fall from a car driving at high speed: A case report.

Science.gov (United States)

Maujean, Géraldine; Guinet, Tiphaine; Malicier, Daniel

2016-04-01

In cases of falls, the key issue for forensic scientists is to determine the manner of death. They must distinguish between accidental falls, suicidal falls, falls including blows and falls caused by a blow. Several strategies have been proposed in the literature to help explain injury patterns. Here, we report an original case of a man who died after jumping from a car moving at high speed. A mathematical and modeling approach was developed to reconstruct the trajectory of the body in order to understand the injury pattern and apparent discrepancy between the high speed of the car from which the victim jumped and the topography of the bone fractures, which were limited to the skull. To define the initial values of the model's parameters, a technical vehicle evaluation and several test jumps at low speed were carried out. We studied in greater detail the trajectory of three characteristic points corresponding to the dummy's center of gravity, head and right foot. Calculations were made with and without the air friction effect to show its influence. Finally, we were successful in modeling the initial trajectory of the body and the variation of its head energy over time, which were consistent with the injuries observed. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

High-risk factors of parotid lymph node metastasis in nasopharyngeal carcinoma: a case-control study

International Nuclear Information System (INIS)

Wang, Hong-zhi; Cao, Cai-neng; Luo, Jing-wei; Yi, Jun-lin; Huang, Xiao-dong; Zhang, Shi-ping; Wang, Kai; Qu, Yuan; Xiao, Jian-ping; Li, Su-yan; Gao, Li; Xu, Guo-zhen

2016-01-01

Although parotid-sparing IMRT decreased the dose distribution of parotid, parotid region recurrence has been reported. Prophylactic irradiation in parotid area would be necessary in patients with high risk of parotid lymph node metastasis (PLNM). This study was to detect the high-risk factors of PLNM in nasopharyngeal carcinoma. This was a 1:2 case-control study. All patients in this study were newly diagnosed NPC with N2-3 classification from January 2005 to December 2012. Cases were 22 sides with ipsilateral PLNM. Controls were 44 patients who were randomly selected from N2-3 disease in database. 20/1096 (1.82 %) NPC patients were found PLNM. Sum of the longest diameter for multiple lymph nodes (SLD) in level II was larger in case group than that in control group (6.0 cm vs. 3.6 cm, p = 0.003). Level II lymph node necrosis, level Va/b involvement, and rare neck areas involvement were more common in case group (p = 0.016, p = 0.034, and p < 0.001, respectively). RPN, level III, and level IV metastases showed no significant difference between the two groups. Multivariate analysis in logistic regression showed that only SLD ≥5 cm in II area (OR = 4.11, p = 0.030) and rare neck areas involvement (OR = 3.95, p = 0.045) were associated with PLNM in NPC patients. PLNM was an uncommon event in NPC patients. SLD ≥5 cm in level II and involvement in rare-neck areas may be potentially high-risk factors for PLNM. Sparing parotid in IMRT was not recommended for NPC patients with high risks of PLNM

Integration testing through reusing representative unit test cases for high-confidence medical software.

Science.gov (United States)

Shin, Youngsul; Choi, Yunja; Lee, Woo Jin

2013-06-01

As medical software is getting larger-sized, complex, and connected with other devices, finding faults in integrated software modules gets more difficult and time consuming. Existing integration testing typically takes a black-box approach, which treats the target software as a black box and selects test cases without considering internal behavior of each software module. Though it could be cost-effective, this black-box approach cannot thoroughly test interaction behavior among integrated modules and might leave critical faults undetected, which should not happen in safety-critical systems such as medical software. This work anticipates that information on internal behavior is necessary even for integration testing to define thorough test cases for critical software and proposes a new integration testing method by reusing test cases used for unit testing. The goal is to provide a cost-effective method to detect subtle interaction faults at the integration testing phase by reusing the knowledge obtained from unit testing phase. The suggested approach notes that the test cases for the unit testing include knowledge on internal behavior of each unit and extracts test cases for the integration testing from the test cases for the unit testing for a given test criteria. The extracted representative test cases are connected with functions under test using the state domain and a single test sequence to cover the test cases is produced. By means of reusing unit test cases, the tester has effective test cases to examine diverse execution paths and find interaction faults without analyzing complex modules. The produced test sequence can have test coverage as high as the unit testing coverage and its length is close to the length of optimal test sequences. Copyright © 2013 Elsevier Ltd. All rights reserved.

On the Zeeman Effect in highly excited atoms: 2. Three-dimensional case

International Nuclear Information System (INIS)

Baseia, B.; Medeiros e Silva Filho, J.

1984-01-01

A previous result, found in two-dimensional hydrogen-atoms, is extended to the three-dimensional case. A mapping of a four-dimensional space R 4 onto R 3 , that establishes an equivalence between Coulomb and harmonic potentials, is used to show that the exact solution of the Zeeman effect in highly excited atoms, cannot be reached. (Author) [pt

Robust synchronization analysis in nonlinear stochastic cellular networks with time-varying delays, intracellular perturbations and intercellular noise.

Science.gov (United States)

Chen, Po-Wei; Chen, Bor-Sen

2011-08-01

Naturally, a cellular network consisted of a large amount of interacting cells is complex. These cells have to be synchronized in order to emerge their phenomena for some biological purposes. However, the inherently stochastic intra and intercellular interactions are noisy and delayed from biochemical processes. In this study, a robust synchronization scheme is proposed for a nonlinear stochastic time-delay coupled cellular network (TdCCN) in spite of the time-varying process delay and intracellular parameter perturbations. Furthermore, a nonlinear stochastic noise filtering ability is also investigated for this synchronized TdCCN against stochastic intercellular and environmental disturbances. Since it is very difficult to solve a robust synchronization problem with the Hamilton-Jacobi inequality (HJI) matrix, a linear matrix inequality (LMI) is employed to solve this problem via the help of a global linearization method. Through this robust synchronization analysis, we can gain a more systemic insight into not only the robust synchronizability but also the noise filtering ability of TdCCN under time-varying process delays, intracellular perturbations and intercellular disturbances. The measures of robustness and noise filtering ability of a synchronized TdCCN have potential application to the designs of neuron transmitters, on-time mass production of biochemical molecules, and synthetic biology. Finally, a benchmark of robust synchronization design in Escherichia coli repressilators is given to confirm the effectiveness of the proposed methods. Copyright © 2011 Elsevier Inc. All rights reserved.

High Prevalence of Human Papillomavirus in Colorectal Cancer in Hispanics: A Case-Control Study

Directory of Open Access Journals (Sweden)

Raul D. Bernabe-Dones

2016-01-01

Full Text Available The role of Human Papillomavirus (HPV in colorectal carcinogenesis remains elusive. Based on the high incidence of HPV-associated malignancies among Puerto Rican Hispanics, this study aimed to assess the prevalence of HPV infection and viral integration in colorectal tissues in order to evaluate its putative role in colorectal cancer (CRC. In this case-control study, the prevalence of HPV infection in CRC (cases n = 45 and normal colon mucosa from cancer-free subjects (controls n = 36 was assessed by a nested PCR strategy. HPV-16 genotyping was performed in HPV-positive tissues and the physical status of the HPV-16 genome was determined by E2 detection. HPV was detected in 19 of 45 (42.2% CRC cases (mean age 61.1 ± 10.7 years, 24 males and in 1 of 36 (2.8% controls (mean age 60.9 ± 9.6 years, 24 males with an OR = 25.58 (95% CI 3.21 to 203.49. HPV-16 was detected in 63.2% of the HPV-positive colorectal tumors; genome integration was observed in all HPV-16 positive cases. This is the first report showing the high prevalence of HPV infections in Caribbean Hispanic colorectal tumors. Despite evidence of HPV integration into the host genome, further mechanistic analysis examining HPV oncoprotein expression and the putative role of these oncoproteins in colorectal carcinogenesis is warranted.

On the Role of Ammonia in Arctic Aerosol Nucleation and Cloud Formation

Science.gov (United States)

Browse, J.; Dall'Osto, M.; Geels, C.; Skov, H.; Massling, A.; Boertmann, D.; Beddows, D.; Gordon, H.; Pringle, K.

2017-12-01

This study investigates the importance of ammonia in Arctic aerosol nucleation and the formation of cloud condensation nuclei (CCN) at high-latitudes. The importance of atmospheric nucleation processes to summertime Arctic aerosol concentration has been frequently noted at ground-stations, during campaigns and within models (which typically predict that the majority of aerosol in the Arctic summertime boundary layer derives from nucleation). However, as nucleation mechanisms in global models have increased in complexity (improving model skill globally) our skill in the Arctic has generally decreased. This decrease in model skill is likely due to a lack of organic compounds (monterpenes etc.) in the modelled high Arctic which have been identified as a key component in atmospheric nucleation in the mid-latitudes and thus incorporated into many global nucleation parametrisations. Recently it has been suggested that ammonia (also identified as a potentially important component in atmospheric nucleation) may control nucleation processes in the Arctic. However, the source (or sources) of Arctic ammonia remain unclear. Here, we use modelling, long-term aerosol in-situ observations, high resolution sea-ice satellite observations and new emission inventories to investigate the link between ammonia sources (including bird colonies, sea-ice melt and open ocean in the marginal ice zones) and nucleation events in the mid-to-high Arctic, and thus quantify the importance of individual ammonia sources to Arctic-wide CCN and cloud droplet populations.

Cryogenic magnet case and distributed structural materials for high-field superconducting magnets

International Nuclear Information System (INIS)

Summers, L.T.; Miller, J.R.; Kerns, J.A.; Myall, J.O.

1987-01-01

The superconducting magnets of the Tokamak Ignition/Burn Experimental Reactor (TIBER II) will generate high magnetic fields over large bores. The resulting electromagnetic forces require the use of large volumes of distributed steel and thick magnet case for structural support. Here we review the design allowables, calculated loads and forces, and structural materials selection for TIBER II. 7 refs., 2 figs., 3 tabs

High risk human papillomavirus in the periodontium : A case control study

Directory of Open Access Journals (Sweden)

Anna Shipilova

2017-01-01

Full Text Available Background: Human papilloma viruses (HPVs are small DNA viruses that have been identified in periodontal pocket as well as gingival sulcus. High risk HPVs are also associated with a subset of head and neck carcinomas. It is thought that the periodontium could be a reservoir for HPV. Aims: 1. Detection of Human Papilloma virus (HPV in periodontal pocket as well as gingival of patients having localized chronic periodontitis and gingival sulcus of periodontally healthy subjects. 2. Quantitative estimation of E6 and E7 mRNA in subjects showing presence of HPV3. To assess whether periodontal pocket is a reservoir for HPV. Settings and Design: This case-control study included 30 subjects with localized chronic Periodontitis (cases and 30 periodontally healthy subjects (controls. Two samples were taken from cases, one from periodontal pocket and one from gingival sulcus and one sample was taken from controls. Methods and Materials: Samples were collected in the form of pocket scrapings and gingival sulcus scrapings from cases and controls respectively. These samples were sent in storage media for identification and estimation of E6/E7 mRNA of HPV using in situ hybridization and flow cytometry. Statistical analysis: Statistical analysis was done by using, mean, percentage and Chi Square test. A statistical package SPSS version 13.0 was used to analyze the data. P value < 0.05 was considered as statistically significant. Results: pocket samples as well as sulcus samples for both cases and controls were found to contain HPV E6/E7 mRNAInterpretation and Conclusion: Presence of HPV E6/E7 mRNA in periodontium supports the hypothesis that periodontal tissues serve as a reservoir for latent HPV and there may be a synergy between oral cancer, periodontitis and HPV. However prospective studies are required to further explore this link.

Malaria Cases in the U.S. Reach 40-Year High: Information and Guidance for Clinicians

Centers for Disease Control (CDC) Podcasts

This podcast is an overview of the Clinician Outreach and Communication Activity (COCA) Call: Malaria Cases in the U.S. Reach 40-Year High: Information and Guidance for Clinicians. The number of malaria cases reported in the United States in 2011 was the largest since 1971, representing a 14 percent increase from 2010 and a 48 percent increase from 2008. A CDC subject matter expert describes malaria prevention strategies aimed at reducing the risk of malaria in travelers, discusses the diagnosis of malaria in patients with suspect malaria, and explains the treatment options for confirmed malaria cases.

Transcription of Biotic Stress Associated Genes in White Clover (Trifolium repens L.) Differs in Response to Cyst and Root-Knot Nematode Infection.

Science.gov (United States)

Islam, Afsana; Mercer, Chris F; Leung, Susanna; Dijkwel, Paul P; McManus, Michael T

2015-01-01

The transcription of four members of the Kunitz proteinase inhibitor (KPI) gene family of white clover (Trifolium repens L.), designated as Tr-KPI1, Tr-KPI2, Tr-KPI4 and Tr-KPI5, was investigated at both local infection (roots) and systemic (leaf tissue) sites in white clover in response to infection with the clover root knot nematode (CRKN) Meloidogyne trifoliophila and the clover cyst nematode (CCN) Heterodera trifolii. Invasion by the CRKN resulted in a significant decrease in transcript abundance of Tr-KPI4 locally at both 4 days post-infection (dpi) and at 8 dpi, and an increase in transcription of Tr-KPI1 systemically at 8 dpi. In contrast, an increase in transcript abundance of all four Tr-KPI genes locally at 4 and 8 dpi, and an increase of Tr-KPI1, Tr-KPI2, and Tr-KPI5 at 8 dpi systemically was observed in response to infection with the CCN. Challenge of a resistant (R) genotype and a susceptible (S) genotype of white clover with the CCN revealed a significant increase in transcript abundance of all four Tr-KPI genes locally in the R genotype, while an increase in abundance of only Tr-KPI1, Tr-KPI2, and Tr-KPI5 was observed in the S genotype, and only at 4 dpi. The transcript abundance of a member of the1-AMINOCYCLOPROPANE-1-CARBOXYLATE (ACC) SYNTHASE gene family from white clover (Tr-ACS1) was significantly down-regulated locally in response to CRKN infection at 4 and 8 dpi and at 4 dpi, systemically, while abundance increased locally and systemically at 8 dpi in response to CCN challenge. Conversely, the abundance of the jasmonic acid (JA) signalling gene, CORONATINE-INSENSITIVE PROTEIN 1 from white clover (Tr-COI1) increased significantly at 8 dpi locally in response to CRKN infection, but decreased at 8 dpi in response to CCN infection. The significance of this differential regulation of transcription is discussed with respect to differences in infection strategy of the two nematode species.

Volume do embrião estimado pela ultra-sonografia tridimensional entre a sétima e a décima semana de gestação Embryo volume estimated by three-dimensional ultrasonography at seven to ten weeks of pregnancy

Directory of Open Access Journals (Sweden)

João Bortoletti Filho

2008-10-01

Full Text Available OBJETIVO: avaliar a evolução do volume do embrião (VE entre a sétima e a décima semana de gestação por meio da ultra-sonografia tridimensional. MÉTODOS: realizou-se um estudo de corte transversal com 63 gestantes normais entre a sétima e a décima semana. Os exames ultra-sonográficos foram realizados por meio de um transdutor endocavitário volumétrico. Para o cálculo do VE, utilizou-se o método VOCAL (Virtual Organ Computer-aided Analysis com ângulo de rotação de 12º, com delimitação de 15 planos seqüenciais. Para o VE foram calculadas médias, medianas, desvios padrão e valores máximo e mínimo em todas as idades gestacionais. Para se avaliar a correlação entre o VE e o comprimento cabeça-nádega (CCN foi criado gráfico de dispersão, sendo o ajuste realizado pelo coeficiente de determinação (R². Para se determinarem intervalos de referência do VE em função do CCN, utilizou-se a seguinte fórmula: percentil =VE+K versus dp, com K=1,96. RESULTADOS: o CCN variou de 9,0 a 39,7 mm, com média de 23,9 mm (±7,9 mm, enquanto o VE variou de 0,1 a 7,6 cm³, com média de 2,7 cm³ (±3,2 cm³. O VE foi altamente correlacionado com o CCN, sendo que o melhor ajuste foi obtido com regressão quadrática (VE=0,165 - 0,055 x CCN + 0,005 x CCN²; R²=0,853. O VE médio variou de 0,1 (-0,3 a 0,5 cm³ a 6,7 cm³ (3,8 a 9,7 cm³ no intervalo de 9 a 40 mm do CCN. Neste intervalo o VE aumentou 67 vezes, enquanto o CCN aumentou apenas 4,4 vezes. CONCLUSÕES: o VE é um parâmetro mais sensível que o CCN para avaliar o crescimento embrionário entre a sétima e a décima semana de gestação.PURPOSE: to evaluate the embryo's volume (EV between the seventh and the tenth gestational week, through tridimensional ultrasonography. METHODS: a transversal study with 63 normal pregnant women between the seventh and the tenth gestational week. The ultrasonographical exams have been performed with a volumetric abdominal transducer. Virtual

High-dose I-131 MIBG treatment for young children with high-risk neuroblastoma, and its practical problem. From the experience of the youngest case in Japan

International Nuclear Information System (INIS)

Araki, Raita; Nishimura, Ryosei; Mase, Shintaro

2012-01-01

High-dose I-131 MIBG (metaiodobenzylguanidine) therapy combined with auto- or allo-hematopoietic stem cell transplantation is becoming a potential treatment for patients with high-risk neuroblastoma worldwide. However, only older children, who can perform personal care, had been given high-dose I-131 MIBG treatment to avoid the needless radiation exposure to caregivers and medical staff in Japan. In this case report, we have used the high dose MIBG therapy followed by autologous PBSCT (peripheral blood stem cell transplantation) for a 1-year-old boy with a newly diagnosed high-risk neuroblastoma with MYCN amplifications. The total radiation exposure to all parties involved was very limited, even in the youngest case in Japan, probably due to adequate preparations. This encouraging experience may remove the age limit for high-dose I-131 MIBG treatment for the patients with high-risk neuroblastoma in Japan. (author)

Maternal and foetal outcome of 206 high risk pregnancy cases in border guard hospital, dhaka.

Science.gov (United States)

Shapla, N R; Islam, M A; Shahida, S M; Parveen, Z; Lipe, Y S

2015-04-01

This observational study was carried out to identify the various types of high risk pregnancy and to determine the maternal and foetal outcome. The study was carried out on 206 pregnant high risk women in the Gynecology and Obstetrics department of Border Guard Hospital, Dhaka from January 2012 to December 2012. During mentioned period among 598 pregnant women 206 high risk pregnancy cases were randomly selected. Pregnant women (gestational age from 34 weeks upto 40 weeks) having medical condition and pregnancy related high risk factors were included and uncomplicated pregnancy, pregnancy before 37 weeks, post dated pregnancy were excluded from this study. Data was collected from semi structured history sheet and data analysis done by percentage. High risk pregnant women were grouped into three. Group A and Group B includes pregnant women having medical condition before and during pregnancy respectively. Group C consists of pregnant women had pregnancy related high risk issues. Among 206 high risk pregnancy cases majority 47.57% women had medical condition during pregnancy, 31.55% patient had medical condition before pregnancy. Among them majority 30.58% of the patient suffered from pregnancy induced hypertension, 15.04% patients suffered from gestational Diabetes Mellitus and premature rupture of membranes were 12.13%. In this study majority 43.68% of high risk pregnant patients were in age group of 30-35 years, 19.90% pregnant women were in age group of >35 years and 19.40% were in age group of upto 20 years. Among study groups maximum 65.04% of the patients were multiparous. Among 206 study population 60.19% high risk pregnant women were at term at the time of delivery and 39.8% women delivered their babies preterm. Caesarean section was done in 69.41% of high risk pregnant women. After delivery majority 77.66% women had no complication, only 10.19%, 8.25%, 2.91% and 0.97% high risk pregnant women suffered from fever, UTI, abdominal wound infection and post

High laboratory cost predicted per tuberculosis case diagnosed with increased case finding without a triage strategy.

Science.gov (United States)

Dunbar, R; Naidoo, P; Beyers, N; Langley, I

2017-09-01

Cape Town, South Africa. To model the effects of increased case finding and triage strategies on laboratory costs per tuberculosis (TB) case diagnosed. We used a validated operational model and published laboratory cost data. We modelled the effect of varying the proportion with TB among presumptive cases and Xpert cartridge price reductions on cost per TB case and per additional TB case diagnosed in the Xpert-based vs. smear/culture-based algorithms. In our current scenario (18.3% with TB among presumptive cases), the proportion of cases diagnosed increased by 8.7% (16.7% vs. 15.0%), and the cost per case diagnosed increased by 142% (US$121 vs. US$50). The cost per additional case diagnosed was US$986. This would increase to US$1619 if the proportion with TB among presumptive cases was 10.6%. At 25.9-30.8% of TB prevalence among presumptive cases and a 50% reduction in Xpert cartridge price, the cost per TB case diagnosed would range from US$50 to US$59 (comparable to the US$48.77 found in routine practice with smear/culture). The operational model illustrates the effect of increased case finding on laboratory costs per TB case diagnosed. Unless triage strategies are identified, the approach will not be sustainable, even if Xpert cartridge prices are reduced.

Biomass Burning Organic Aerosol as a Modulator of Droplet Number in the Southern Atlantic

Science.gov (United States)

Kacarab, M.; Howell, S. G.; Small Griswold, J. D.; Thornhill, K. L., II; Wood, R.; Redemann, J.; Nenes, A.

2017-12-01

Aerosols play a significant yet highly variable role in local and global air quality and climate. They act as cloud condensation nuclei (CCN) and both scatter and absorb radiation, lending a large source of uncertainty to climate predictions. Biomass burning organic aerosol (BBOA) can drastically elevate CCN concentrations, but the response in cloud droplet number may be suppressed or even reversed due to low supersaturations that develop from strong competition for water vapor. Constraining droplet response to BBOA is a key factor to understanding aerosol-cloud interactions. The southeastern Atlantic (SEA) cloud deck off the west coast of central Africa is a prime opportunity to study these cloud-BBOA interactions for marine stratocumulus as during winter in the southern hemisphere the SEA cloud deck is overlain by a large, optically thick BBOA plume. The NASA ObseRvations of Aerosols above Clouds and their intEractionS (ORACLES) study focuses on increasing the understanding of how these BBOA affect the SEA cloud deck. Measurements of CCN concentration, aerosol size distribution and composition, updraft velocities, and cloud droplet number in and around the SEA cloud deck and associated BBOA plume were taken aboard the NASA P-3 aircraft during the first two years of the ORACLES campaign in September 2016 and August 2017. Here we evaluate the predicted and observed droplet number sensitivity to the aerosol fluctuations and quantify, using the data, the drivers of droplet number variability (vertical velocity or aerosol properties) as a function of biomass burning plume characteristics. Over the course of the campaign, different levels of BBOA influence in the marine boundary layer (MBL) were observed, allowing for comparison of cloud droplet number, hygroscopicity parameter (κ), and maximum in-cloud supersaturation over a range of "clean" and "dirty" conditions. Droplet number sensitivity to aerosol concentration, κ, and vertical updraft velocities are also

Particles from a Diesel ship engine: Mixing state on the nano scale and cloud condensation abilities

Science.gov (United States)

Lieke, K. I.; Rosenørn, T.; Fuglsang, K.; Frederiksen, T.; Butcher, A. C.; King, S. M.; Bilde, M.

2012-04-01

Transport by ship plays an important role in global logistics. Current international policy initiatives by the International Maritime Organization (IMO) are taken to reduce emissions from ship propulsion systems (NO and SO, primarily). However, particulate emissions (e.g. soot) from ships are yet not regulated by legislations. To date, there is still a lack of knowledge regarding the global and local effects of the particulate matter emitted from ships at sea. Particles may influence the climate through their direct effects (scattering and absorption of long and shortwave radiation) and indirectly through formation of clouds. Many studies have been carried out estimating the mass and particle number from ship emissions (e.g. Petzold et al. 2008), many of them in test rig studies (e.g. Kasper et al. 2007). It is shown that particulate emissions vary with engine load and chemical composition of fuels. Only a few studies have been carried out to characterize the chemical composition and cloud-nucleating ability of the particulate matter (e.g. Corbett et al. 1997). In most cases, the cloud-nucleating ability of emission particles is estimated from number size distribution. We applied measurements to characterize particulate emissions from a MAN B&W Low Speed engine on test bed. A unique data set was obtained through the use of a scanning mobility particle sizing system (SMPS), combined with a cloud condensation nucleus (CCN) counter and a thermodenuder - all behind a dilution system. In addition, impactor samples were taken on nickel grids with carbon foil for use in an electron microscope (EM) to characterize the mineral phase and mixing state of the particles. The engine was operated at a series of different load conditions and an exhaust gas recirculation (EGR) system was applied. Measurements were carried out before and after the EGR system respectively. Our observations show significant changes in number size distribution and CCN activity with varying conditions

IgG4-related hypophysitis is highly prevalent among cases of histologically confirmed hypophysitis.

Science.gov (United States)

Bernreuther, Christian; Illies, Christopher; Flitsch, Jörg; Buchfelder, Michael; Buslei, Rolf; Glatzel, Markus; Saeger, Wolfgang

2017-11-01

IgG4-related disease is an immune-mediated disease with manifestations in most organ systems among them the pituitary gland. To date, few cases of histologically confirmed cases of IgG-related hypophysitis have been reported. The aim of this study was to retrospectively determine the prevalence of IgG4-related hypophysitis among cases previously diagnosed as primary hypophysitis (lymphocytic hypophysitis, granulomatous hypophysitis and hypophysitis not otherwise specified). Histological and immunohistochemical analysis revealed that 12 of 29 cases (41.4%) previously diagnosed as primary hypophysitis fulfilled the criteria for IgG4-related disease and, thus, IgG4-related hypophysitis should always be considered in the differential diagnosis of primary hypophysitis. All cases of IgG4-related hypophysitis showed a dense lymphoplasmacytic infiltrate with more than 10 IgG4-positive cells per high power field and a ratio of IgG4/IgG-positive cells of more than 40%, whereas storiform fibrosis was an inconsistent histological feature and was also seen in few cases of non-IgG-related hypophysitis, thus lacking sensitivity and specificity. Obliterative phlebitis was not seen in any case. Thus, histological criteria defined for IgG4-related disease in other organs should be modified for IgG4-related hypophysitis, accordingly. © 2016 International Society of Neuropathology.

Successful and Sustained Leadership: A Case Study of a Jesuit High School President

Science.gov (United States)

García-Tuñón, Guillermo M.; Cistone, Peter J.; Reio, Thomas G., Jr.

2016-01-01

The purpose of this research was to examine the factors and elements that contributed to the success and longevity of an exemplary Jesuit high school leader. Through an exemplary case study approach, qualitative and quantitative data were collected. Instead of merely employing one of two leadership frames, the convergent evidence suggested that…

Cognitive Control Network Contributions to Memory-Guided Visual Attention.

Science.gov (United States)

Rosen, Maya L; Stern, Chantal E; Michalka, Samantha W; Devaney, Kathryn J; Somers, David C

2016-05-01

Visual attentional capacity is severely limited, but humans excel in familiar visual contexts, in part because long-term memories guide efficient deployment of attention. To investigate the neural substrates that support memory-guided visual attention, we performed a set of functional MRI experiments that contrast long-term, memory-guided visuospatial attention with stimulus-guided visuospatial attention in a change detection task. Whereas the dorsal attention network was activated for both forms of attention, the cognitive control network(CCN) was preferentially activated during memory-guided attention. Three posterior nodes in the CCN, posterior precuneus, posterior callosal sulcus/mid-cingulate, and lateral intraparietal sulcus exhibited the greatest specificity for memory-guided attention. These 3 regions exhibit functional connectivity at rest, and we propose that they form a subnetwork within the broader CCN. Based on the task activation patterns, we conclude that the nodes of this subnetwork are preferentially recruited for long-term memory guidance of visuospatial attention. Published by Oxford University Press 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Single and two-phase similarity analysis of a reduced-scale natural convection loop relative to a full-scale prototype

International Nuclear Information System (INIS)

Botelho, David A.; Faccini, Jose L.H.

2002-01-01

The main topic in this paper is a new device being considered to improve nuclear reactor safety employing the natural circulation. A scaled experiment used to demonstrate the performance of the device is also described. We also applied a similarity analysis method for single and two-phase natural convection loop flow to the IEN CCN experiment and to an APEX like experiment to verify the degree of similarity relative to a full-scale prototype like the AP600. Most of the CCN similarity numbers that represent important single and two-phase similarity conditions are comparable to the APEX like loop non-dimensional numbers calculated employing the same methodology. Despite the much smaller geometric, pressure, and power scales, we conclude that the IEN CCN has single and two-phase natural circulation similarity numbers that represent fairly well the full-scale prototype. even lacking most complementary primary and safety systems, this IEN circuit provided a much valid experience to develop human, experimental, and analytical resources, besides its utilization as a training tool. (author)

Investigations of aerosol impacts on hurricanes: virtual seeding flights

Directory of Open Access Journals (Sweden)

G. G. Carrio

2011-03-01

Full Text Available This paper examines the feasibility of mitigating the intensity of hurricanes by enhancing the CCN concentrations in the outer rainband region. Increasing CCN concentrations would cause a reduced collision and coalescence, resulting in more supercooled liquid water to be transported aloft which then freezes and enhances convection via enhanced latent heat of freezing. The intensified convection would condense more water ultimately enhancing precipitation in the outer rainbands. Enhanced evaporative cooling from the increased precipitation in the outer rainbands would produce stronger and more widespread areal cold pools which block the flow of energy into the storm core, ultimately inhibiting the intensification of the tropical cyclone.

We designed a series of multi-grid for which the time of the "virtual flights" as well as the aerosol release rates are varied. A code that simulates the flight of a plane is used to increase the CCN concentrations as an aircraft flies. Results show a significant sensitivity to both the seeding time and the aerosol release rates and support the aforementioned hypothesis.

Power/energy use cases for high performance computing

Energy Technology Data Exchange (ETDEWEB)

Laros, James H. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kelly, Suzanne M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hammond, Steven [National Renewable Energy Lab. (NREL), Golden, CO (United States); Elmore, Ryan [National Renewable Energy Lab. (NREL), Golden, CO (United States); Munch, Kristin [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2013-12-01

Power and Energy have been identified as a first order challenge for future extreme scale high performance computing (HPC) systems. In practice the breakthroughs will need to be provided by the hardware vendors. But to make the best use of the solutions in an HPC environment, it will likely require periodic tuning by facility operators and software components. This document describes the actions and interactions needed to maximize power resources. It strives to cover the entire operational space in which an HPC system occupies. The descriptions are presented as formal use cases, as documented in the Unified Modeling Language Specification [1]. The document is intended to provide a common understanding to the HPC community of the necessary management and control capabilities. Assuming a common understanding can be achieved, the next step will be to develop a set of Application Programing Interfaces (APIs) to which hardware vendors and software developers could utilize to steer power consumption.

False-positive buprenorphine EIA urine toxicology results due to high dose morphine: a case report.

Science.gov (United States)

Tenore, Peter L

2012-01-01

In monitoring a patient with chronic pain who was taking high-dose morphine and oxycodone with weekly urine enzymatic immunoassay (EIA) toxicology testing, the authors noted consistent positives for buprenorphine. The patient was not taking buprenorphine, and gas chromatography/mass spectroscopy (GCMS) testing on multiple samples revealed no buprenorphine, indicating a case of false-positive buprenorphine EIAs in a high-dose opiate case. The authors discontinued oxycodone for a period of time and then discontinued morphine. Urine monitoring with EIAs and GCMS revealed false-positive buprenorphine EIAs, which remained only when the patient was taking morphine. When taking only oxycodone and no morphine, urine samples became buprenorphine negative. When morphine was reintroduced, false-positive buprenorphine results resumed. Medical practitioners should be aware that high-dose morphine (with morphine urine levels turning positive within the 15,000 to 28,000 mg/mL range) may produce false-positive buprenorphine EIAs with standard urine EIA toxicology testing.

Impact of payment system change from per-case to per-diem on high severity patient's length of stay.

Science.gov (United States)

Jang, Sung-In; Nam, Chung Mo; Lee, Sang Gyu; Kim, Tae Hyun; Park, Sohee; Park, Eun-Cheol

2016-09-01

A new payment system, the diagnosis-related group (DRG) system, and Korean diagnosis procedure combination (KDPC, per-diem) payment system were officially introduced in 2002 and in 2012, respectively. We evaluated the impact of payment system change from per-case to per-diem on high severity patient's length of stay (LOS).Claim data was used. A total of 36,240 case admissions and 72,480 control admissions were included in the analysis. Segmented regression analysis of interrupted time series between cases and controls was conducted. Hospitals that consistently participated in the DRG payment system and changed to the KDPC payment system were defined as case hospitals. Hospitals that consistently participated in the DRG payment system were defined as control hospitals.LOS increased by 0.025 days per month (P = 0.0055) for 3 surgical diagnosis-related admissions due to the bundled payment system change. LOS among emergency admissions also increased and showed an increasing tendency under the KDPC. The LOS increase was observed specifically for complex procedure admissions and high severity cases (CCI 0, 1: 0.022, P = 0.0142; CCI 2, 3: 0.026, P = 0.0288; CCI ≥ 4: 0.055, P = 0.0003).Although both payment systems are optimized to decrease LOS, incentives to reduce LOS are stronger under the DRG system than under the KDPC system. It is worth noting that too strong incentive for reducing LOS is suitable to high severity cases.

A new method for calculating number concentrations of cloud condensation nuclei based on measurements of a three-wavelength humidified nephelometer system

Science.gov (United States)

Tao, Jiangchuan; Zhao, Chunsheng; Kuang, Ye; Zhao, Gang; Shen, Chuanyang; Yu, Yingli; Bian, Yuxuan; Xu, Wanyun

2018-02-01

The number concentration of cloud condensation nuclei (CCN) plays a fundamental role in cloud physics. Instrumentations of direct measurements of CCN number concentration (NCCN) based on chamber technology are complex and costly; thus a simple way for measuring NCCN is needed. In this study, a new method for NCCN calculation based on measurements of a three-wavelength humidified nephelometer system is proposed. A three-wavelength humidified nephelometer system can measure the aerosol light-scattering coefficient (σsp) at three wavelengths and the light-scattering enhancement factor (fRH). The Ångström exponent (Å) inferred from σsp at three wavelengths provides information on mean predominate aerosol size, and hygroscopicity parameter (κ) can be calculated from the combination of fRH and Å. Given this, a lookup table that includes σsp, κ and Å is established to predict NCCN. Due to the precondition for the application, this new method is not suitable for externally mixed particles, large particles (e.g., dust and sea salt) or fresh aerosol particles. This method is validated with direct measurements of NCCN using a CCN counter on the North China Plain. Results show that relative deviations between calculated NCCN and measured NCCN are within 30 % and confirm the robustness of this method. This method enables simplerNCCN measurements because the humidified nephelometer system is easily operated and stable. Compared with the method using a CCN counter, another advantage of this newly proposed method is that it can obtain NCCN at lower supersaturations in the ambient atmosphere.

Soil microorganisms and plant diseases associated to cocoa (Theobroma cacao L. genotypes in the Ecuadorian Amazon

Directory of Open Access Journals (Sweden)

Jorge Antonio Freile Almeida

2018-01-01

Full Text Available El objetivo de la presente investigación fue analizar la relación de los microorganismos del suelo y las principales enfermedades que afectan los clones promisorios de cacao (Theobroma cacao L. en la Amazonía Ecuatoriana. Se evaluaron los clones EET-95, EET-96, EET-103 y CCN-51, respectivamente, éste último utilizado como control, para ello, se determinó la cantidad de bacterias, hongos y actinomicetos totales, expresados en unidades formadoras de colonias (UFC por gramo de suelo, presentes en la rizósfera de los tres clones de cacao, así como la aparición de las principales enfermedades que atacan al cultivo del cacao. Los datos fueron analizados estadísticamente mediante ANOVA de un factor y prueba HSD de Tukey p≤0,05. Las bacterias fueron los microorganismos de mayor asociación a los clones en este estudio, seguido de actinomicetos y hongos. El clon CCN-51 presentó la mayor cantidad de bacterias, los clones EET-96 y EET-103, presentaron mayor incidencia de actinomicetos y el clon EET-103, la mayor presencia de hongos. La enfermedad escoba de bruja, cuyo agente causal es Cripinellis perniciosa Sthael Singer., afectó en menor medida a los clones EET-103 y CCN-51, mientras que la moniliasis causada por el hongo Moniliophthora roreri (Cif & Par Evans et al., puso en evidencia al clon EET-103 con la mayor incidencia de esta enfermedad y conversivamente al clon CCN-51 con la menor incidencia del patógeno.

The Hygroscopicity Parameter of Marine Organics in Sea Spray Aerosols

Science.gov (United States)

Boyer, M.; Chang, R. Y. W.

2015-12-01

The effects of aerosols on climate are poorly understood, specifically with respect to their influence on cloud properties. Since oceans cover >70% of Earth's surface, sea spray aerosols (SSA), which act efficiently as cloud condensation nuclei (CCN), may have important implications on Earth's radiation budget. Surface active organic species readily accumulate in the sea surface microlayer (SML), located at the ocean-atmosphere interface, and transfer onto nascent SSA. While it is understood that SSA are commonly enriched with organics, the resulting effect of the organic content on CCN activation remains unresolved. The hygroscopicity parameter, kappa (k), allows for the cloud nucleating properties of individual components to be predicted in particles of mixed composition; however, most studies typically infer k from ambient measurements without assessing the contribution of the individual components to the overall k. In this study, a method for quantifying the cloud nucleating properties of the organic species in surface seawater using k-Kohler theory is proposed. Ambient SML and bulk water samples will be collected and atomized to generate particles such that the overall k can be inferred from CCN measurements. The inorganic and organic components will be quantified, and the organic component will be separated so that the hygroscopicity of only the organic constituents can be determined. By comparing the inferred k values for the samples before and after removal of the inorganic component, the hygroscopicity of the organic constituents alone can be calculated, providing insight on the effect of organic species on CCN activation in SSA.

Analyzing the United States Department of Transportation's Implementation Strategy for High Speed Rail: Three Case Studies

Science.gov (United States)

Robinson, Ryan

High-speed rail (HSR) has become a major contributor to the transportation sector with a strong push by the Obama Administration and the Department of Transportation to implement high-speed rail in the United States. High-speed rail is a costly transportation alternative that has the potential displace some car and airport travel while increase energy security and environmental sustainability. This thesis will examine the United States high-speed rail implementation strategy by comparing it to the implementation strategies of France, Japan, and Germany in a multiple case study under four main criteria of success: economic profitability, reliability, safety, and ridership. Analysis will conclude with lessons to be taken away from the case studies and applied to the United States strategy. It is important to understand that this project has not been established to create a comprehensive implementation plan for high-speed rail in the United States; rather, this project is intended to observe the depth and quality of the current United States implementation strategy and make additional recommendations by comparing it with France, Japan, and Germany.

Earthworks logistics in the high density urban development conditions - case study

Science.gov (United States)

Sobotka, A.; Blajer, M.

2017-10-01

Realisation of the construction projects on highly urbanised areas carries many difficulties and logistic problems. Earthworks conducted in such conditions constitute a good example of how important it is to properly plan the works and use the technical means of the logistics infrastructure. The construction processes on the observed construction site, in combination with their external logistics service are a complex system, difficult for mathematical modelling and achievement of appropriate data for planning the works. The paper shows describe and analysis of earthworks during construction of the Centre of Power Engineering of AGH in Krakow for two stages of a construction project. At the planning stage in the preparatory phase (before realization) and in the implementation phase of construction works (foundation). In the first case, an example of the use of queuing theory for prediction of excavation time under random work conditions of the excavator and the associated trucks is provided. In the second case there is a change of foundation works technology resulting as a consequence of changes in logistics earthworks. Observation of the construction has confirmed that the use of appropriate methods of construction works management, and in this case agile management, the time and cost of the project have not been exceeded. The success of a project depends on the ability of the contractor to react quickly when changes occur in the design, technology, environment, etc.

A case of atherosclerotic inferior mesenteric artery aneurysm secondary to high flow state.

Science.gov (United States)

Troisi, Nicola; Esposito, Giovanni; Cefalì, Pietro; Setti, Marco

2011-07-01

Inferior mesenteric artery aneurysms are very rare and they are among the rarest of visceral artery aneurysms. Sometimes, the distribution of the blood flow due to chronic atherosclerotic occlusion of some arteries can establish an increased flow into a particular supplying district (high flow state). A high flow state in a stenotic inferior mesenteric artery in compensation for a mesenteric occlusive disease can produce a rare form of aneurysm. We report the case of an atherosclerotic inferior mesenteric aneurysm secondary to high flow state (association with occlusion of the celiac trunk and severe stenosis of the superior mesenteric artery), treated by open surgical approach. Copyright © 2011 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

Metaphor Comprehension in Autistic Spectrum Disorders: Case Studies of Two High-Functioning Children

Science.gov (United States)

Melogno, Sergio; D'Ardia, Caterina; Pinto, Maria Antonietta; Levi, Gabriel

2012-01-01

This article presents case studies on metaphor comprehension in two boys with high-functioning autistic spectrum disorder, aged 9;1 (9 years, 1 month) and 8;11. The participants were assessed twice, before and after an intervention program aimed at improving their social skills. The focus of the article is on the specific patterns exhibited by…

Reducing the uncertainty in background marine aerosol radiative properties using CAM5 model results and CALIPSO-retrievals

Science.gov (United States)

Meskhidze, N.; Gantt, B.; Dawson, K.; Johnson, M. S.; Gasso, S.

2012-12-01

Abundance of natural aerosols in the atmosphere strongly affects global aerosol optical depth (AOD) and influences clouds and the hydrological cycle through its ability to act as cloud condensation nuclei (CCN). Because the anthropogenic contribution to climate forcing represents the difference between the total forcing and that from natural aerosols, understanding background aerosols is necessary to evaluate the influences of anthropogenic aerosols on cloud reflectivity and persistence (so-called indirect radiative forcing). The effects of marine aerosols are explored using remotely sensed data obtained by Cloud-aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) and the NCAR Community Atmosphere Model (CAM5.0), coupled with the PNNL Modal Aerosol Model. CALIPSO-provided high resolution vertical profile information about different aerosol subtypes (defined as clean continental, marine, desert dust, polluted continental, polluted dust, and biomass burning), particulate depolarization ratio (or particle non-sphericity), reported aerosol color ratio (the ratio of aerosol backscatter at the two wavelengths) and lidar ratios over different parts of the oceans are compared to model-simulations to help evaluate the contribution of biogenic aerosol to CCN budget in the marine boundary layer. Model-simulations show that over biologically productive ocean waters primary organic aerosols of marine origin can contribute up to a 20% increase in CCN (at a supersaturation of 0.2%) number concentrations. Corresponding changes associated with cloud properties (liquid water path and droplet number) can decrease global annual mean indirect radiative forcing of anthropogenic aerosol (less cooling) by ~0.1 Wm-2 (7%). This study suggests ignoring the complex chemical composition and size distribution of sea spray particles could result in considerable uncertainties in predicted anthropogenic aerosol indirect effect.

Leaders' Experiences with High School-College Writing Center Collaborations: A Qualitative Multiple-Case Study

Science.gov (United States)

Story, Julie A.

2014-01-01

The purpose of this qualitative multiple-case study was to explore academic leaders' experiences with the organizational elements of their own high school-college writing center collaborations. Conjoining theories framed this study: collaborative leadership theory, Kenneth Bruffee's notion of social constructionism and collaborative learning…

Conflicts in Chemistry: The Case of Plastics, a Role-Playing Game for High School Chemistry Students

Science.gov (United States)

Cook, Deborah H.

2014-01-01

Conflicts in Chemistry: The Case of Plastics, an innovative role-playing activity for high school students, was developed by the Chemical Heritage Foundation to promote increased public understanding of chemistry. The pilot program included three high school teachers and their students at three different schools and documented implementation and…

Secondary organic aerosols. Chemical aging, hygroscopicity, and cloud droplet activation

Energy Technology Data Exchange (ETDEWEB)

Buchholz, Angela

2011-07-06

Atmospheric aerosols have an important impact on the radiation balance, and thus, on the climate of the Earth. Aerosol particles scatter and absorb incoming solar and terrestrial radiation. Apart from this direct effect, aerosol particles act as cloud condensation nuclei (CCN), thereby greatly influencing the microphysics of clouds. Secondary organic aerosols (SOA) are an important fraction of the total aerosol mass. In many environments these organic compounds are mainly products of the oxidation of biogenic volatile organic compounds (VOC). In this study the hygroscopic growth and CCN activation of biogenic SOA were investigated which was formed by the oxidation of VOC with O{sub 3} and photochemically formed OH radicals under low NO{sub x} conditions. For this purpose, a complex mixture of VOC emitted by boreal tree species as gas-phase precursors was used in the Juelich Plant Atmosphere Chamber (JPAC). In long-term studies in the atmosphere simulation chamber SAPHIR {alpha}-pinene or a defined mixture of {alpha}-pinene, {beta}-pinene, limonene, ocimene, {delta}-3-carene served as precursors. Initial precursor concentrations between 40 and 1000 ppbC were investigated. The observed SOA particles were slightly hygroscopic with an average hygroscopicity parameter {kappa}(CCN) = 0.10 {+-} 0.02 and {kappa}(90%RH) = 0.05 {+-} 0.01. Closure between hygroscopic growth and CCN activation data could be achieved allowing either surface tension reduction, limited solubility, or non-ideality of the solution in the droplet. The SOA solutions in equilibrium with RH <95% are possible highly non-ideal. Therefore the organic-water interaction were investigated by applying the UNIFAC model. Calculations for surrogate compounds exhibited the same strong concentration (i.e. RH) dependence of {kappa} at sub-saturation. The growth curves could be fitted and CCN activation predicted by assuming a binary mixture of water and one hypothetical organic compound. The occurrence of

Improving tuberculosis case detection in underdeveloped multi-ethnic regions with high disease burden: a case study of integrated control program in China.

Science.gov (United States)

Li, Jun; Liu, Xiao-Qiu; Jiang, Shi-Wen; Li, Xue; Yu, Fei; Wang, Yan; Peng, Yong; Gu, Xiao-Ming; Sun, Yan-Ni; Zhang, Hui; Wang, Li-Xia

2017-11-29

In the underdeveloped multi-ethnic regions of China, high tuberculosis (TB) burden and regional inequity in access to healthcare service increase the challenge of achieving the End TB goals. Among all the provinces, the highest TB burden is reported in Xinjiang, where ethnic minorities and older people have suffered most. However, current case-finding strategy is inadequate given the complex social determinants and suboptimal case detection rates. Thus, we developed an integrated TB control program to improve case detection and conducted a pilot in Xinjiang from 2014 to 2015. In this case study, we summarized the activities and key findings. We also shared the experiences and challenges of implementing interventions and provided recommendations to inform the TB control program in the future. The pilot interventions were implemented in one selected town in Yining based on local TB control programs. By applying tailor-made educational materials, outreach TB educational activities were conducted in diverse ways. In 22 Masjids, the trained imams promoted TB education to the Muslims, covering 20,440 person-times in 88 delivered preaching sessions. In seven schools, 1944 students were educated by the teachers and contributed to educating 6929 family members. In the village communities, 13,073 residents participated in household education and screening. Among them, 12,292 people aged under 65 years were investigated for suspicious pulmonary TB symptoms, where six TB patients were diagnosed out of 89 TB suspects; 781 older people were mobilized for screening directly by chest X-ray, where 10 patients were diagnosed out of 692 participants. Supportive healthcare system, multi-sectoral cooperation and multi-channel financing mechanism were the successful experiences of implementation. The interventions were proved to be more effective than the previous performance: the number of TB suspects consulting doctors and patients detected increased by 50% and 26%, respectively

High-output cardiac failure secondary to multiple vascular malformations in the liver: case report

International Nuclear Information System (INIS)

Spaner, S.; Demeter, S.; Lien, D.; Shapiro, J.; McCarthy, M.; Raymond, G.

2001-01-01

High-output cardiac failure is associated with several systemic illnesses, including hyperthyroidism, thiamine deficiency, severe anemia, multiple myeloma, Paget's disease of bone and Osler-Weber-Rendu syndrome. We present an unusual case of a woman with high-output cardiac failure as a result of multiple arteriovenous fistulas in the liver, most likely representing an unusual variant of Osler-Weber-Rendu syndrome (i.e., no other telangiectasias or a family history of vascular malformations was demonstrated). (author)

Critical operations capabilities in a high cost environment: a multiple case study

Science.gov (United States)

Sansone, C.; Hilletofth, P.; Eriksson, D.

2018-04-01

Operations capabilities have been a popular research area for many years and several frameworks have been proposed in the literature. The current frameworks do not take specific contexts into consideration, for instance a high cost environment. This research gap is of particular interest since a manufacturing relocation process has been ongoing the last decades, leading to a huge amount of manufacturing being moved from high to low cost environments. The purpose of this study is to identify critical operations capabilities in a high cost environment. The two research questions were: What are the critical operations capabilities dimensions in a high cost environment? What are the critical operations capabilities in a high cost environment? A multiple case study was conducted and three Swedish manufacturing firms were selected. The study was based on the investigation of an existing framework of operations capabilities. The main dimensions of operations capabilities included in the framework were: cost, quality, delivery, flexibility, service, innovation and environment. Each of the dimensions included two or more operations capabilities. The findings confirmed the validity of the framework and its usefulness in a high cost environment and a new operations capability was revealed (employee flexibility).

Global distribution and climate forcing of marine organic aerosol: 1. Model improvements and evaluation

Directory of Open Access Journals (Sweden)

N. Meskhidze

2011-11-01

Full Text Available Marine organic aerosol emissions have been implemented and evaluated within the National Center of Atmospheric Research (NCAR's Community Atmosphere Model (CAM5 with the Pacific Northwest National Laboratory's 7-mode Modal Aerosol Module (MAM-7. Emissions of marine primary organic aerosols (POA, phytoplankton-produced isoprene- and monoterpenes-derived secondary organic aerosols (SOA and methane sulfonate (MS⁻ are shown to affect surface concentrations of organic aerosols in remote marine regions. Global emissions of submicron marine POA is estimated to be 7.9 and 9.4 Tg yr⁻¹, for the Gantt et al. (2011 and Vignati et al. (2010 emission parameterizations, respectively. Marine sources of SOA and particulate MS⁻ (containing both sulfur and carbon atoms contribute an additional 0.2 and 5.1 Tg yr⁻¹, respectively. Widespread areas over productive waters of the Northern Atlantic, Northern Pacific, and the Southern Ocean show marine-source submicron organic aerosol surface concentrations of 100 ng m⁻³, with values up to 400 ng m⁻³ over biologically productive areas. Comparison of long-term surface observations of water insoluble organic matter (WIOM with POA concentrations from the two emission parameterizations shows that despite revealed discrepancies (often more than a factor of 2, both Gantt et al. (2011 and Vignati et al. (2010 formulations are able to capture the magnitude of marine organic aerosol concentrations, with the Gantt et al. (2011 parameterization attaining better seasonality. Model simulations show that the mixing state of the marine POA can impact the surface number concentration of cloud condensation nuclei (CCN. The largest increases (up to 20% in CCN (at a supersaturation (S of 0.2% number concentration are obtained over biologically productive ocean waters when marine organic aerosol is assumed to be externally mixed with sea-salt. Assuming

Methodological Proposal for Identification and Evaluation of Environmental Aspects and Impacts of IPEN Nuclear Facilities: A Case Study Applied to the Nuclear Fuel Center

International Nuclear Information System (INIS)

Mattos, Luis A. Terribile de; Filho, Tufic Madi; Meldonian, Nelson Leon

2013-06-01

This work presents an application of Failure Mode Effect Analysis (FMEA) to the process of identification of environmental aspects and impacts as a part of implementation and maintenance of an Environmental Management System (EMS) in accordance with the ISO 14001 standard. Also, it can contribute, as a complement, to the evaluation and improvement of safety of the installation focused. The study was applied to the Nuclear Fuel Center (CCN) of Nuclear and Energy Research Institute (IPEN), situated at the Campus of University of Sao Paulo, Brazil. The CCN facility has the objective of promoting scientific research and of producing nuclear fuel elements for the IEA-R1 Research Reactor. To identify the environmental aspects of the facility activities, products, and services, a systematic data collection was carried out by means of personal interviews, documents, reports and operation data records consulting. Furthermore, the processes and their interactions, failure modes, besides their causes and effects to the environment, were identified. As a result of a careful evaluation of these causes it was possible to identify and to classify the major potential environmental impacts, in order to set up and put in practice an Environmental Control Plan for the installation under study. The results have demonstrated the validity of the FMEA application to nuclear facility processes, identifying environmental aspects and impacts, whose controls are critical to achieve compliance with the environmental requirements of the Integrated Management System of IPEN. It was demonstrated that the methodology used in this work is a powerful management tool for resolving issues related to the conformity with applicable regulatory and legal requirements of the Brazilian Nuclear Energy Commission (CNEN) and the Brazilian Institute of Environment (IBAMA). (authors)

Case Studies of Leading Edge Small Urban High Schools. Relevance Strategic Designs: 4. Boston Arts Academy

Science.gov (United States)

Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

2008-01-01

This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

Case Studies of Leading Edge Small Urban High Schools. Relevance Strategic Designs: 6. Perspectives Charter School

Science.gov (United States)

Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

2008-01-01

This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

Case Studies of Leading Edge Small Urban High Schools. Relevance Strategic Designs: 7. TechBoston Academy

Science.gov (United States)

Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

2008-01-01

This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

How African-American Elementary Students in High-Poverty Schools Experience Creative Expression: A Case Study Approach

Science.gov (United States)

Willis, Belinda F.

2016-01-01

Literature that addresses how the arts enhance student learning through creative expression is minimal. This is especially true for African-American elementary students from high-poverty backgrounds. The purpose of this study was to employ a case study design to explore how African-American elementary students in high-poverty schools experience…

Case Managers for High-Risk, High-Cost Patients as Agents and Street-Level Bureaucrats.

Science.gov (United States)

Swanson, Jeffrey; Weissert, William G

2017-08-01

Case management programs often designate a nurse or social worker to take responsibility for guiding care when patients are expected to be expensive or risk a major decline. We hypothesized that though an intuitively appealing idea, careful program design and faithful implementation are essential if case management programs are to succeed. We employed two theory perspectives, principal-agent framework and street-level bureaucratic theory to describe the relationship between program designers (principals) and case managers (agents/street-level bureaucrats) to review 65 case management studies. Most programs were successful in limited program-specific process and outcome goals. But there was much less success in cost-saving or cost-effectiveness-the original and overarching goal of case management. Cost results might be improved if additional ideas of agency and street-level theory were adopted, specifically, incentives, as well as "green tape," clear rules, guidelines, and algorithms relating to resource allocation among patients.

N-enriched multilayered porous carbon derived from natural casings for high-performance supercapacitors

Science.gov (United States)

Xu, Zongying; Li, Yu; Li, Dandan; Wang, Dawei; Zhao, Jing; Wang, Zhifeng; Banis, Mohammad N.; Hu, Yongfeng; Zhang, Huaihao

2018-06-01

In this study, N-enriched multilayered porous activated carbon (LPAC), using natural casings as precursor, was fabricated by a facile carbonization and subsequent KOH activation procedure. The influence of the mass ratio of KOH to carbonized material on pore-structure and surface element composition of LPACs was investigated by a variety of means, such as SEM, HRTEM, BET, Raman, XRD, XPS and XAS. Owing to the unique multilayered texture and nitrogen (N) and oxygen (O) rich feature of natural casings, the resulting LPACs possess interconnected and developed porous structure with N- and O-enriched functional groups, contributing to larger pseudocapacitance. With the rise of mass ratio, the specific surface area (SSA) and average pore size of LPACs increased. The final materials were endowed with a desirable SSA (3100 m2 g-1) and high N content (6.34 at.%). Meanwhile, N- and O-enriched LPAC-4 exhibited a high specific capacitance (307.5 F g-1 at a current density of 0.5 A g-1 in 6 M KOH aqueous solution), excellent rate performance (63.4% capacitance retention at 20 A g-1) and good cycling stability (7.1% capacitance loss after 5000 cycles). Furthermore, the assembled symmetrical supercapacitor (LPAC-4//LPAC-4) with a wide voltage window of 1.4 V delivered a remarkable energy density of 11.6 Wh kg-1 at a power density of 297 W kg-1. These results suggested that unique LPACs derived from natural casings are a promising material for supercapacitors.

Effects of 20–100 nm particles on liquid clouds in the clean summertime Arctic

Directory of Open Access Journals (Sweden)

W. R. Leaitch

2016-09-01

Full Text Available Observations addressing effects of aerosol particles on summertime Arctic clouds are limited. An airborne study, carried out during July 2014 from Resolute Bay, Nunavut, Canada, as part of the Canadian NETCARE project, provides a comprehensive in situ look into some effects of aerosol particles on liquid clouds in the clean environment of the Arctic summer. Median cloud droplet number concentrations (CDNC from 62 cloud samples are 10 cm−3 for low-altitude cloud (clouds topped below 200 m and 101 cm−3 for higher-altitude cloud (clouds based above 200 m. The lower activation size of aerosol particles is  ≤  50 nm diameter in about 40 % of the cases. Particles as small as 20 nm activated in the higher-altitude clouds consistent with higher supersaturations (S for those clouds inferred from comparison of the CDNC with cloud condensation nucleus (CCN measurements. Over 60 % of the low-altitude cloud samples fall into the CCN-limited regime of Mauritsen et al. (2011, within which increases in CDNC may increase liquid water and warm the surface. These first observations of that CCN-limited regime indicate a positive association of the liquid water content (LWC and CDNC, but no association of either the CDNC or LWC with aerosol variations. Above the Mauritsen limit, where aerosol indirect cooling may result, changes in particles with diameters from 20 to 100 nm exert a relatively strong influence on the CDNC. Within this exceedingly clean environment, as defined by low carbon monoxide and low concentrations of larger particles, the background CDNC are estimated to range between 16 and 160 cm−3, where higher values are due to activation of particles  ≤  50 nm that likely derive from natural sources. These observations offer the first wide-ranging reference for the aerosol cloud albedo effect in the summertime Arctic.

High Flow Nasal Cannula Therapy for Improving Obstructive Sleep Apnea: A Case Report

Directory of Open Access Journals (Sweden)

Se Joong Kim

2015-06-01

Full Text Available Although continuous positive airway pressure is the treatment of choice for obstructive sleep apnea, its compliance is low. Therefore, alternative therapeutic strategies are often required. High flow nasal cannula therapy uses an air compressor to deliver a constant flow of oxygen via the nasal cannula at a maximum of 60 L/m. It can produce positive end expiratory pressure and increase end expiratory pharyngeal pressure, which can help to alleviate upper airway obstruction. This is a case report of high flow nasal cannula therapy for a 71 year-old man. He had an obstructive sleep apnea and severe desaturation but failed to use continuous positive airway pressure. He underwent titration with high flow nasal cannula under polysomnography. Using high flow nasal cannula at an airflow of 45 L/m, his apnea-hypopnea, respiratory arousal and oxygen desaturation were improved. Importantly, he is very compliant with high flow nasal cannula therapy.

High-Definition transcranial direct current stimulation in early onset epileptic encephalopathy: a case study.

Science.gov (United States)

Meiron, Oded; Gale, Rena; Namestnic, Julia; Bennet-Back, Odeya; David, Jonathan; Gebodh, Nigel; Adair, Devin; Esmaeilpour, Zeinab; Bikson, Marom

2018-01-01

Early onset epileptic encephalopathy is characterized by high daily seizure-frequency, multifocal epileptic discharges, severe psychomotor retardation, and death at infancy. Currently, there are no effective treatments to alleviate seizure frequency and high-voltage epileptic discharges in these catastrophic epilepsy cases. The current study examined the safety and feasibility of High-Definition transcranial direct current stimulation (HD-tDCS) in reducing epileptiform activity in a 30-month-old child suffering from early onset epileptic encephalopathy. HD-tDCS was administered over 10 intervention days spanning two weeks including pre- and post-intervention video-EEG monitoring. There were no serious adverse events or side effects related to the HD-tDCS intervention. Frequency of clinical seizures was not significantly reduced. However, interictal sharp wave amplitudes were significantly lower during the post-intervention period versus baseline. Vital signs and blood biochemistry remained stable throughout the entire study. These exploratory findings support the safety and feasibility of 4 × 1 HD-tDCS in early onset epileptic encephalopathy and provide the first evidence of HD-tDCS effects on paroxysmal EEG features in electroclinical cases under the age of 36 months. Extending HD-tDCS treatment may enhance electrographic findings and clinical effects.

Teacher Mathematical Literacy: Case Study of Junior High School Teachers in Pasaman

Science.gov (United States)

Ahmad, D.; Suherman, S.; Maulana, H.

2018-04-01

The aim of this paper was to examine the ability of junior high school mathematics teachers to solve mathematical literacy base Problems (PISA and PISA-like problems) for the case Pasaman regency. The data was collected by interviews and test. As the results of this study, teacher ability in solving mathematical literacy base problems for level 1 until 3 has been good, but for level 4 or above is still low. It is caused by teacher knowledge about mathematical literacy still few.

A Case of High-Grade Neuroendocrine Carcinoma That Improved with Bevacizumab plus Modified FOLFOX6 as the Fourth-Line Chemotherapy

Directory of Open Access Journals (Sweden)

Satoshi Takeuchi

2011-05-01

Full Text Available High-grade neuroendocrine carcinoma differs from usual neuroendocrine carcinoma, and its prognosis is dismal. In this case report, a case of high-grade neuroendocrine carcinoma that improved with bevacizumab plus modified FOLFOX6 as the fourth-line chemotherapy is presented. A 29-year-old male with a huge liver tumor was diagnosed with high-grade neuroendocrine carcinoma originating from the liver. Multiple liver and bone metastases were found one month after surgery. He was treated with three chemotherapy regimens used for the management of small-cell lung cancer with extensive disease. However, none of them could be maintained because of tumor progression. He was then treated with bevacizumab plus modified FOLFOX6 as the fourth-line regimen. Dramatic tumor shrinkage was obtained, and a partial response was achieved. This case suggests that high-grade neuroendocrine carcinoma can be treated with bevacizumab in combination with cytotoxic chemotherapy.

How important is organic aerosol hygroscopicity to aerosol indirect forcing?

International Nuclear Information System (INIS)

Liu Xiaohong; Wang Jian

2010-01-01

Organics are among the most abundant aerosol components in the atmosphere. However, there are still large uncertainties with emissions of primary organic aerosol (POA) and volatile organic compounds (VOCs) (precursor gases of secondary organic aerosol, SOA), formation of SOA, and chemical and physical properties (e.g., hygroscopicity) of POA and SOA. All these may have significant impacts on aerosol direct and indirect forcing estimated from global models. In this study a modal aerosol module (MAM) in the NCAR community atmospheric model (CAM) is used to examine sensitivities of aerosol indirect forcing to hygroscopicity (represented by a single parameter 'κ' ) of POA and SOA. Our model simulation indicates that in the present-day (PD) condition changing the 'κ' value of POA from 0 to 0.1 increases the number concentration of cloud condensational nuclei (CCN) at supersaturation S = 0.1% by 40-80% over the POA source regions, while changing the 'κ' value of SOA by ± 50% (from 0.14 to 0.07 and 0.21) changes the CCN concentration within 40%. There are disproportionally larger changes in CCN concentration in the pre-industrial (PI) condition. Due to the stronger impact of organics hygroscopicity on CCN and cloud droplet number concentration at PI condition, global annual mean anthropogenic aerosol indirect forcing (AIF) between PD and PI conditions reduces with the increase of the hygroscopicity of organics. Global annual mean AIF varies by 0.4 W m -2 in the sensitivity runs with the control run of - 1.3 W m -2 , highlighting the need for improved understanding of organics hygroscopicity and its representation in global models.

A new consideration for the heat transfer coefficient and an analysis of the thermal stress of the high-interim pressure turbine casing model

International Nuclear Information System (INIS)

Um, Dall Sun

2004-01-01

In real design of the high and interim pressure turbine casing, it is one of the important things to figure out its thermal strain exactly. In this paper, with the establishment of the new concept for the heat transfer coefficient of steam that is one of the factors in analysis of the thermal stress for turbine casing, an analysis was done for one of the high and interim pressure turbine casings in operating domestically. The sensitivity analysis of the heat transfer coefficient of steam to the thermal strain of the turbine casing was done with a 2-D simple model. The analysis was also done with switching of the material properties of the turbine casing and resulted in that the thermal strain of the turbine casing was not so sensitive to the heat transfer coefficient of steam. On the basis of this, 3-D analysis of the thermal strain for the high and interim pressure turbine casing was done

Malaria Cases in the U.S. Reach 40-Year High: Information and Guidance for Clinicians

Centers for Disease Control (CDC) Podcasts

2014-02-26

This podcast is an overview of the Clinician Outreach and Communication Activity (COCA) Call: Malaria Cases in the U.S. Reach 40-Year High: Information and Guidance for Clinicians. The number of malaria cases reported in the United States in 2011 was the largest since 1971, representing a 14 percent increase from 2010 and a 48 percent increase from 2008. A CDC subject matter expert describes malaria prevention strategies aimed at reducing the risk of malaria in travelers, discusses the diagnosis of malaria in patients with suspect malaria, and explains the treatment options for confirmed malaria cases.  Created: 2/26/2014 by Center for Global Health (CGH); Malaria Branch; Emergency Risk Communication Branch (ERCB); Office of Public Health Preparedness and Response (OPHPR).   Date Released: 2/26/2014.

Cloud condensation nuclei activity and hygroscopicity of fresh and aged cooking organic aerosol

Science.gov (United States)

Li, Yanwei; Tasoglou, Antonios; Liangou, Aikaterini; Cain, Kerrigan P.; Jahn, Leif; Gu, Peishi; Kostenidou, Evangelia; Pandis, Spyros N.

2018-03-01

Cooking organic aerosol (COA) is potentially a significant fraction of organic particulate matter in urban areas. COA chemical aging experiments, using aerosol produced by grilling hamburgers, took place in a smog chamber in the presence of UV light or excess ozone. The water solubility distributions, cloud condensation nuclei (CCN) activity, and corresponding hygroscopicity of fresh and aged COA were measured. The average mobility equivalent activation diameter of the fresh particles at 0.4% supersaturation ranged from 87 to 126 nm and decreased for aged particles, ranging from 65 to 88 nm. Most of the fresh COA had water solubility less than 0.1 g L-1, even though the corresponding particles were quite CCN active. After aging, the COA fraction with water solubility greater than 0.1 g L-1 increased more than 2 times. Using the extended Köhler theory for multiple partially soluble components in order to predict the measured activation diameters, the COA solubility distribution alone could not explain the CCN activity. Surface tensions less than 30 dyn cm-1 were required to explain the measured activation diameters. In addition, COA particles appear to not be spherical, which can introduce uncertainties into the corresponding calculations.

Crystal structure of chlorido(dimethyl sulfoxide-κSbis[4-(pyridin-2-ylbenzaldehyde-κ3C2,N]iridium(III acetonitrile monosolvate

Directory of Open Access Journals (Sweden)

Andrew J. Peloquin

2017-09-01

Full Text Available The title compound, [IrCl(C12H8NO2{(CH32SO}]·H3CCN or [IrCl(fppy2(DMSO]·H3CCN [where fppy is 4-(pyridin-2-ylbenzaldehyde and DMSO is dimethyl sulfoxide], is a mononuclear iridium(III complex including two fppy ligands, a sulfur-coordinating DMSO ligand, and one terminal chloride ligand that define a distorted octahedral coordination sphere. The complex crystallizes from 1:1 DMSO–acetonitrile as an acetonitrile solvate. In the crystal, weak C—H...O and C—H...N hydrogen-bonding interactions between adjacent complexes and between the acetonitrile solvent and the complex consolidate the packing.

The embodied spaces of children with complex care needs: Effects on the social realities and power negotiations of families.

Science.gov (United States)

Woodgate, Roberta L; Zurba, Melanie; Edwards, Marie; Ripat, Jacquie D; Rempel, Gina

2017-07-01

This paper presents research findings that advance knowledge around the power and agency families with children with complex care needs (CCN). Our conceptual framework uses concepts from geography towards situating the experiences and social realities of family carers within the 'embodied space of care'. The data originate from a longitudinal qualitative study of Canadian families with children with CCN. Findings reveal that interactions and decision-making processes relating to health and everyday life were complex and socially interconnected, and emphasize the need for provisions for family-based decision-making and enhanced social inclusion of families and the importance of the renegotiation of power. Copyright © 2017 Elsevier Ltd. All rights reserved.

High Spicy Food Intake and Risk of Cancer: A Meta-analysis of Case-control Studies.

Science.gov (United States)

Chen, Yu-Heng; Zou, Xiao-Nong; Zheng, Tong-Zhang; Zhou, Qi; Qiu, Hui; Chen, Yuan-Li; He, Mei; Du, Jia; Lei, Hai-Ke; Zhao, Ping

2017-09-20

Studies on the association between spicy food intake and cancer risk have reported inconsistent results. We quantitatively assessed this association by conducting a meta-analysis based on evidence from case-control studies. PubMed, EMBASE, and the Cochrane Library were searched for eligible publications. Combined odds ratios (OR s) with their 95% confidence interval (CI) were calculated using a random- or fixed-effects model. The methodological quality of the included articles was assessed using the Newcastle-Ottawa scale (NOS). All data were analyzed using STATA 11.0 software (version 11.0; StataCorp., College Station, TX, USA). Subgroup analyses were also performed with stratification by region, sex, number of cases, cancer subtype, source of the control group, and NOS score. A total 39 studies from 28 articles fulfilled the inclusion criteria for the meta-analysis (7884 patients with cancer and 10,142 controls). Comparison of the highest versus lowest exposure category in each study revealed a significant OR of 1.76 (95% CI = 1.35-2.29) in spite of significant heterogeneity (P cases, different sources of the control group, and high-quality articles (NOS score of ≥ 7). However, no statistically significant association was observed for women, esophageal cancer, gallbladder cancer, or low-quality articles (NOS score of case-control studies suggested that a higher level of spicy food intake may be associated with an increased incidence of cancer despite significant heterogeneity. More studies are warranted to clarify our understanding of the association between high spicy food intake and the risk of cancer.

Pulmonary paracoccidioidomycosis: A case report with high-resolution computed tomography findings

Directory of Open Access Journals (Sweden)

M. Armas

2012-07-01

Full Text Available Paracoccidioidomycosis is a systemic mycosis which is endemic in rural areas of Latin America, an important European source of immigrants and a growing European touristic destination as well, with most cases occurring in Brazil, Argentina, Venezuela and Colombia. The authors report a case of a 43-year-old man who previously worked in Venezuela and is living in Portugal for 8 years, presenting with a single cutaneous lesion. Despite the absence of valuable respiratory complaints, severe lung damage was found with high-resolution computed tomography (HRCT. Biopsy of the cutaneous lesion and mycologic sputum examination were performed revealing Paracoccidioides brasiliensis infection. Resumo: A Paracoccidioidomicose é uma micose sistémica endémica nas áreas rurais da América Latina, uma fonte importante de imigrantes e destino de emigração e turismo europeu, a maioria dos casos ocorrendo no Brasil, Argentina, Venezuela e Colômbia. Os autores descrevem o caso clínico de um paciente com 43 anos, anteriormente emigrado na Venezuela e residente em Portugal há 8 anos, que se apresenta com lesão cutânea isolada. Embora sem queixas relevantes do foro respiratório, apresentava extensas lesões do parênquima pulmonar caracterizadas por tomografia computorizada de alta resolução (TCAR. Foi realizada biópsia da lesão cutânea e exame micológico da expetoração que revelaram infeção por Paracoccidioides brasiliensis (PB. Keywords: Paracoccidioidomycosis, Paracoccidioides brasiliensis, Pulmonary fibrosis, High-resolution computed tomography, Palavras-chave: Paracoccidioidomicose, Paracoccidioides brasiliensis, Fibrose pulmonar, Tomografia computorizada de alta resolução

Evidence of direct cardiac damage following high-intensity exercise in chronic energy restriction: A case report and literature review.

Science.gov (United States)

Baird, Marianne F; Grace, Fergal; Sculthorpe, Nicholas; Graham, Scott M; Fleming, Audrey; Baker, Julien S

2017-07-01

Following prolonged endurance events such as marathons, elevated levels of cardiospecific biomarkers are commonly reported. Although transiently raised levels are generally not considered to indicate clinical myocardial damage, comprehension of this phenomenon remains incomplete. The popularity of high-intensity interval training highlights a paucity of research measuring cardiac biomarker response to this type of exercise. This a posteriori case report discusses the elevation of cardiac troponins (cTn) associated with short interval, high-intensity exercise. In this case report, an apparently healthy 29-year-old recreationally active female presented clinically raised cardiac troponin I (cTnI) levels (>0.04 ng/mL), after performing high-intensity cycle ergometer sprints. As creatine kinase (CK) is expressed by multiple organs (e.g., skeletal muscle, brain, and myocardium), cTnI assays were performed to determine any changes in total serum CK levels not originating from skeletal muscle damage. A posteriori the individual's daily energy expenditure indicated chronically low-energy availability. Psychometric testing suggested that the individual scored positive for disordered eating, highly for fatigue levels, and low in mental health components. The current case report provides novel evidence of elevated cTnI occurring as a result of performing short duration, high intensity, cycle ergometer exercise in an individual with self-reported chronically depleted energy balance. A schematic to identify potentially "at risk" individuals is presented. Considering this as a case report, results cannot be generalized; however, the main findings suggest that individuals who habitually restrict their calorie intake below their bodies' daily energy requirements, may have elevated biomarkers of exercise induced myocardial stress from performing high-intensity exercise.

The influence of erupting lateral teeth on maxillary anterior crowding in two Angle Class I maloclussion cases with high and low angles

Directory of Open Access Journals (Sweden)

Hiroshi Ueda

2016-01-01

Full Text Available Two cases of anterior crowding, both Skeletal Class I and Angle Class I maloclussion, one being low angle and the other high angle respectively, respectively, were treated and evaluated to ascertain whether or not there is a relationship among disproportionate mesial axial angulation of the maxillary lateral teeth and the Frankfurt Horizontal-Functional Occlusal plane, therefore generating maxillary anterior crowding. Both cases were Japanese boys, the first one aged 9 years 10 months with chief complaint being anterior crowding and the second case aged 7 years and 8 months complaining of inadequate space for satisfying canine eruption. During and after the second stage of orthodontic treatment on both cases, several radiographic analysis were performed to assess treatment progress and retention; from these radiographs, it was noticed among other findings that in the high-angle case, the axial angulations of the maxillary lateral incisors were markedly smaller than in the low-angle case, thus indicating mesial tipping in the upper dental arch. This decreased mesial axial angulation of the lateral teeth observed at high angles may potentially cause maxillary space deficiency.

Weatherization Beyond the Numbers: Case Studies of Fifteen High-performing Weatherization Agencies - Conducted May 2011 through July 2012

Energy Technology Data Exchange (ETDEWEB)

Tonn, Bruce Edward [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Rose, Erin M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hawkins, Beth A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2014-09-01

The report presents fifteen individual case studies of high-performing and unique local weatherization agencies. This research was one component of the retrospective evaluation of the U.S. Department of Energy s Weatherization Assistance Program. The agencies were chosen to represent a range of contexts and approaches to weatherization. For example, the set of agencies includes a mix of urban and rural agencies, those that mainly use in-house crews to weatherize homes versus those that use contractor crews, and a mix of locations, from very cold climates to moderate to hot humid and dry climates. The case studies were mainly based on site visits to the agencies that encompassed interviews with program directors, weatherization crews, and recipients of weatherization. This information was supplemented by secondary materials. The cases document the diversity of contexts and challenges faced by the agencies and how they operate on a day-by-day basis. The cases also high common themes found throughout the agencies, such as their focus on mission and respect for their clients.

Pyogenic Arthritis of the Ankle Joint Following a High-Voltage Electrical Burn in the Lower Extremity: A Case Report

Energy Technology Data Exchange (ETDEWEB)

Kim, Kuk Seon; Lee, Gyung Kyu; Kang, Ik Won; Hwang, Dae Hyun; Lee, Eil Seong; Min, Seon Jung; Han, You Mie [Dept. of Radiology, Hangang Scared Heart Hospital, Hallym University College of Medicine, Seoul (Korea, Republic of); Lee, Eil Seong [Dept.of Radiology, Gyeongju Hospital, Dongguk University College of Medicine, Gyeongju (Korea, Republic of)

2011-04-15

A high-voltage electrical burn caused extensive deep muscle injuries beneath a relatively small skin wound at the contact point. Hidden, undetected deep muscle injuries have a tendency for progressive tissue necrosis, which can lead to major amputations or sepsis. The radiologic features of this rare, sometimes life-threatening injury have occasionally been described in the literature. However, to the best of our knowledge, there have been no reports on a case of pyogenic arthritis of the ankle joint following a high-voltage electrical burn involving the lower extremity. We report a case of the pyogenic arthritis of the ankle joint following a high-voltage electrical burn involving the lower extremity.

Theoretical basis for convective invigoration due to increased aerosol concentration

Directory of Open Access Journals (Sweden)

Z. J. Lebo

2011-06-01

Full Text Available The potential effects of increased aerosol loading on the development of deep convective clouds and resulting precipitation amounts are studied by employing the Weather Research and Forecasting (WRF model as a detailed high-resolution cloud resolving model (CRM with both detailed bulk and bin microphysics schemes. Both models include a physically-based activation scheme that incorporates a size-resolved aerosol population. We demonstrate that the aerosol-induced effect is controlled by the balance between latent heating and the increase in condensed water aloft, each having opposing effects on buoyancy. It is also shown that under polluted conditions, increases in the CCN number concentration reduce the cumulative precipitation due to the competition between the sedimentation and evaporation/sublimation timescales. The effect of an increase in the IN number concentration on the dynamics of deep convective clouds is small and the resulting decrease in domain-averaged cumulative precipitation is shown not to be statistically significant, but may act to suppress precipitation. It is also shown that even in the presence of a decrease in the domain-averaged cumulative precipitation, an increase in the precipitation variance, or in other words, andincrease in rainfall intensity, may be expected in more polluted environments, especially in moist environments.

A significant difference exists between the predictions based on the bin and bulk microphysics schemes of precipitation and the influence of aerosol perturbations on updraft velocity within the convective core. The bulk microphysics scheme shows little change in the latent heating rates due to an increase in the CCN number concentration, while the bin microphysics scheme demonstrates significant increases in the latent heating aloft with increasing CCN number concentration. This suggests that even a detailed two-bulk microphysics scheme, coupled to a detailed activation scheme, may not be

Identification and quantification of particle growth channels during new particle formation

Directory of Open Access Journals (Sweden)

M. R. Pennington

2013-10-01

Full Text Available Atmospheric new particle formation (NPF is a key source of ambient ultrafine particles that may contribute substantially to the global production of cloud condensation nuclei (CCN. While NPF is driven by atmospheric nucleation, its impact on CCN concentration depends strongly on atmospheric growth mechanisms since the growth rate must exceed the loss rate due to scavenging in order for the particles to reach the CCN size range. In this work, chemical composition measurements of 20 nm diameter particles during NPF in Hyytiälä, Finland, in March–April 2011 permit identification and quantitative assessment of important growth channels. In this work we show the following: (A sulfuric acid, a key species associated with atmospheric nucleation, accounts for less than half of particle mass growth during this time period; (B the sulfate content of a growing particle during NPF is quantitatively explained by condensation of gas-phase sulfuric acid molecules (i.e., sulfuric acid uptake is collision-limited; (C sulfuric acid condensation substantially impacts the chemical composition of preexisting nanoparticles before new particles have grown to a size sufficient to be measured; (D ammonium and sulfate concentrations are highly correlated, indicating that ammonia uptake is driven by sulfuric acid uptake; (E sulfate neutralization by ammonium does not reach the predicted thermodynamic end point, suggesting that a barrier exists for ammonia uptake; (F carbonaceous matter accounts for more than half of the particle mass growth, and its oxygen-to-carbon ratio (~ 0.5 is characteristic of freshly formed secondary organic aerosol; and (G differences in the overall growth rate from one formation event to another are caused by variations in the growth rates of all major chemical species, not just one individual species.

Development of Integrative STEM Curriculum: A Multiple Case Study of Multi-Disciplinary Teams in Two Pennsylvania High Schools

Science.gov (United States)

Rider-Bertrand, Joey H.

At the start of the 21st century, STEM education was a new priority in many schools as the focus shifted from separate disciplines to integrative STEM education. Unfortunately, there was limited research to offer guidance to practitioners (Brown, 2012; Honey, Pearson & Schweingruber, 2014). This qualitative, multiple case study explored the experiences of two multi-disciplinary teams of secondary teachers from Pennsylvania who developed and implemented integrative STEM curriculum. Four teachers from a rural high school and four teachers from a suburban high school participated in the study. A document review of integrative STEM curriculum and semi-structured interviews were conducted to learn about the curriculum development process and teachers' perceptions regarding conditions that support or hinder success. Individual and cross-case analyses were performed to establish findings and themes. Although the individual case themes varied slightly, the cross-case themes and assertions that emerged provided highly sought after guidance to practitioners and added to the limited body of research on integrative STEM education. This study found that current curriculum models do not fit integrative STEM curriculum, the development process is fluid, and substantial administrative support and resources are necessary to develop, implement, and sustain integrative STEM education programs. The results offered implications for all educators, as well as two examples of how teachers navigated the terrain of integrative STEM curriculum.

The structure of high altitude O+ energization and outflow: a case study

Directory of Open Access Journals (Sweden)

H. Nilsson

2004-07-01

Full Text Available Multi-spacecraft observations from the CIS ion spectrometers on board the Cluster spacecraft have been used to study the structure of high-altitude oxygen ion energization and outflow. A case study taken from 12 April 2004 is discussed in more detail. In this case the spacecraft crossed the polar cap, mantle and high-altitude cusp region at altitudes between 4RE and 8RE and 2 of the spacecraft provided data. The oxygen ions were seen as a beam with narrow energy distribution, and increasing field-aligned velocity and temperature at higher altitude further in the upstream flow direction. The peak O+ energy was typically just above the highest energy of observed protons. The observed energies reached the upper limit of the CIS ion spectrometer, i.e. 38keV. Moment data from the spacecraft have been cross-correlated to determine cross-correlation coefficients, as well as the phase delay between the spacecraft. Structures in ion density, temperature and field-aligned flow appear to drift with the observed field-perpendicular drift. This, together with a velocity dispersion analysis, indicates that much of the structure can be explained by transverse heating well below the spacecraft. However, temperature isotropy and the particle flux as a function of field-aligned velocity are inconsistent with a single altitude Maxwellian source. Heating over extended altitude intervals, possibly all the way up to the observation point, seem consistent with the observations.

Awake craniotomy for gliomas in a high-field intraoperative magnetic resonance imaging suite: analysis of 42 cases.

Science.gov (United States)

Maldaun, Marcos V C; Khawja, Shumaila N; Levine, Nicholas B; Rao, Ganesh; Lang, Frederick F; Weinberg, Jeffrey S; Tummala, Sudhakar; Cowles, Charles E; Ferson, David; Nguyen, Anh-Thuy; Sawaya, Raymond; Suki, Dima; Prabhu, Sujit S

2014-10-01

The object of this study was to describe the experience of combining awake craniotomy techniques with high-field (1.5 T) intraoperative MRI (iMRI) for tumors adjacent to eloquent cortex. From a prospective database the authors obtained and evaluated the records of all patients who had undergone awake craniotomy procedures with cortical and subcortical mapping in the iMRI suite. The integration of these two modalities was assessed with respect to safety, operative times, workflow, extent of resection (EOR), and neurological outcome. Between February 2010 and December 2011, 42 awake craniotomy procedures using iMRI were performed in 41 patients for the removal of intraaxial tumors. There were 31 left-sided and 11 right-sided tumors. In half of the cases (21 [50%] of 42), the patient was kept awake for both motor and speech mapping. The mean duration of surgery overall was 7.3 hours (range 4.0-13.9 hours). The median EOR overall was 90%, and gross-total resection (EOR ≥ 95%) was achieved in 17 cases (40.5%). After viewing the first MR images after initial resection, further resection was performed in 17 cases (40.5%); the mean EOR in these cases increased from 56% to 67% after further resection. No deficits were observed preoperatively in 33 cases (78.5%), and worsening neurological deficits were noted immediately after surgery in 11 cases (26.2%). At 1 month after surgery, however, worsened neurological function was observed in only 1 case (2.3%). There was a learning curve with regard to patient positioning and setup times, although it did not adversely affect patient outcomes. Awake craniotomy can be safely performed in a high-field (1.5 T) iMRI suite to maximize tumor resection in eloquent brain areas with an acceptable morbidity profile at 1 month.

Effective time management for high performance in an organization Case: Lasaco Assurance PLC

OpenAIRE

Adeojo, Adeyinka

2012-01-01

The main objective of this thesis is to determine the effect of time management on high organizational performance using LASACO ASSURANCE Plc. as a case company. In this thesis, the employees working with the company were sent questionnaires. Their responses were critically analyzed and thus related to the theories. A quantitative approach was used as the methodology. According to the theory, time management is a method for managers to increase work performance effectiveness. Time man...

Characterization of uranium silicide powder using XRD

International Nuclear Information System (INIS)

Garcia, Rafael H.L.; Saliba-Silva, Adonis M.; Carvalho, Elita F.U.; Lima, Nelson B.; Ichikawa, Rodrigo U.; Martinez, Luiz G.

2013-01-01

Uranium silicide (U 3 Si 2 ) is an intermetallic used as nuclear fuel in most modern MTR - Materials Test Reactor. Dispersed in aluminum, this fuel allows high uranium densities, up to 4.8 gU/cm 3 . At IPEN, the fabrication of fuel elements based on U 3 Si 2 for the IEA-R1 reactor is carried out in the Nuclear Fuel Center (CCN), by vacuum induction melting of uranium and silicon, followed by grinding. Before employed in a nuclear reactor, U 3 Si 2 must be submitted to a strict quality control, which includes granulometry, density, X-ray radiography for dispersion homogeneity, chemical and crystallographic characterization. Concerning phase composition for a qualified fuel, the fraction of U 3 Si 2 should be higher than 80wt.%. Aiming at the development of a routine methodology for quantification of phases via analysis of XRD data using the Rietved method, six samples from two production baths of CCN were submitted to X-ray diffraction. The data were analyzed using software GSAS and line profile analysis methods. The results suggest that fusion product have preferred orientation and grinding step is important for a better refinement. (author)

No Need to Wait for Superman: A Case Study of One Unique High School

Science.gov (United States)

Ratcliff, N. J.; Jones, C. R.; Costner, R. H.; Knight, C.; Disney, G.; Savage-Davis, E.; Sheehan, H.; Hunt, G. H.

2012-01-01

Based on a theoretical model developed by Schlechty, this case study focuses on a small high school, located on a college campus and designed to address the educational needs of gifted 9th- through 12th-grade students. Eight teachers who taught 9th- and 12th-grade classes and their 60 students were observed. Each teacher was observed during six…

A Case Study of the In-Class Use of a Video Game for Teaching High School History

Science.gov (United States)

Watson, William R.; Mong, Christopher J.; Harris, Constance A.

2011-01-01

This study examines the case of a sophomore high school history class where "Making History", a video game designed with educational purposes in mind, is used in the classroom to teach about World War II. Data was gathered using observation, focus group and individual interviews, and document analysis. The high school was a rural school…

Cloud residues and interstitial aerosols from non-precipitating clouds over an industrial and urban area in northern China

Science.gov (United States)

Li, Weijun; Li, Peiren; Sun, Guode; Zhou, Shengzhen; Yuan, Qi; Wang, Wenxing

2011-05-01

Most studies of aerosol-cloud interactions have been conducted in remote locations; few have investigated the characterization of cloud condensation nuclei (CCN) over highly polluted urban and industrial areas. The present work, based on samples collected at Mt. Tai, a site in northern China affected by nearby urban and industrial air pollutant emissions, illuminates CCN properties in a polluted atmosphere. High-resolution transmission electron microscopy (TEM) was used to obtain the size, composition, and mixing state of individual cloud residues and interstitial aerosols. Most of the cloud residues displayed distinct rims which were found to consist of soluble organic matter (OM). Nearly all (91.7%) cloud residues were attributed to sulfate-related salts (the remainder was mostly coarse crustal dust particles with nitrate coatings). Half the salt particles were internally mixed with two or more refractory particles (e.g., soot, fly ash, crustal dust, CaSO 4, and OM). A comparison between cloud residues and interstitial particles shows that the former contained more salts and were of larger particle size than the latter. In addition, a somewhat high number scavenging ratio of 0.54 was observed during cloud formation. Therefore, the mixtures of salts with OMs account for most of the cloud-nucleating ability of the entire aerosol population in the polluted air of northern China. We advocate that both size and composition - the two influential, controlling factors for aerosol activation - should be built into all regional climate models of China.

Genetic analysis of high bone mass cases from the BARCOS cohort of Spanish postmenopausal women.

Directory of Open Access Journals (Sweden)

Patricia Sarrión

Full Text Available The aims of the study were to establish the prevalence of high bone mass (HBM in a cohort of Spanish postmenopausal women (BARCOS and to assess the contribution of LRP5 and DKK1 mutations and of common bone mineral density (BMD variants to a HBM phenotype. Furthermore, we describe the expression of several osteoblast-specific and Wnt-pathway genes in primary osteoblasts from two HBM cases. A 0.6% of individuals (10/1600 displayed Z-scores in the HBM range (sum Z-score >4. While no mutation in the relevant exons of LRP5 was detected, a rare missense change in DKK1 was found (p.Y74F, which cosegregated with the phenotype in a small pedigree. Fifty-five BMD SNPs from Estrada et al. [NatGenet 44:491-501,2012] were genotyped in the HBM cases to obtain risk scores for each individual. In this small group of samples, Z-scores were found inversely related to risk scores, suggestive of a polygenic etiology. There was a single exception, which may be explained by a rare penetrant genetic variant, counterbalancing the additive effect of the risk alleles. The expression analysis in primary osteoblasts from two HBM cases and five controls suggested that IL6R, DLX3, TWIST1 and PPARG are negatively related to Z-score. One HBM case presented with high levels of RUNX2, while the other displayed very low SOX6. In conclusion, we provide evidence of lack of LRP5 mutations and of a putative HBM-causing mutation in DKK1. Additionally, we present SNP genotyping and expression results that suggest additive effects of several genes for HBM.

High-Dk piggyback contact lenses over Intacs for keratoconus: a case report.

Science.gov (United States)

Smith, Kyle A; Carrell, James D

2008-07-01

The authors describe a case of a keratoconic patient with Intacs fitted with a high-Dk piggyback contact lens system. A 41-year-old man presented to the clinic 1 week after Intacs surgery for keratoconus with complaints of poor visual acuity (VA) and monocular polyopia OU. The patient was corrected to 20/30 in both eyes with rigid gas permeable contact lenses but could not tolerate the lenses for more than 8 hours OD and 2 hours OS. The patient was then successfully fit with a high-Dk piggyback contact lens system. The patient was able to wear the piggyback contact lenses comfortably 12 to 18 hours per day and was corrected to 20/25 OD, 20/30 OS, and 20/20 OU. Patients with Intacs for keratoconus may require a combination of soft and rigid contact lenses for the best possible VA. Contact lens fitting with a high-Dk piggyback contact lens system can provide optimal comfort, corneal health, and VA for patients with Intacs for keratoconus.

"Best Case/Worst Case": Training Surgeons to Use a Novel Communication Tool for High-Risk Acute Surgical Problems.

Science.gov (United States)

Kruser, Jacqueline M; Taylor, Lauren J; Campbell, Toby C; Zelenski, Amy; Johnson, Sara K; Nabozny, Michael J; Steffens, Nicole M; Tucholka, Jennifer L; Kwekkeboom, Kris L; Schwarze, Margaret L

2017-04-01

Older adults often have surgery in the months preceding death, which can initiate postoperative treatments inconsistent with end-of-life values. "Best Case/Worst Case" (BC/WC) is a communication tool designed to promote goal-concordant care during discussions about high-risk surgery. The objective of this study was to evaluate a structured training program designed to teach surgeons how to use BC/WC. Twenty-five surgeons from one tertiary care hospital completed a two-hour training session followed by individual coaching. We audio-recorded surgeons using BC/WC with standardized patients and 20 hospitalized patients. Hospitalized patients and their families participated in an open-ended interview 30 to 120 days after enrollment. We used a checklist of 11 BC/WC elements to measure tool fidelity and surgeons completed the Practitioner Opinion Survey to measure acceptability of the tool. We used qualitative analysis to evaluate variability in tool content and to characterize patient and family perceptions of the tool. Surgeons completed a median of 10 of 11 BC/WC elements with both standardized and hospitalized patients (range 5-11). We found moderate variability in presentation of treatment options and description of outcomes. Three months after training, 79% of surgeons reported BC/WC is better than their usual approach and 71% endorsed active use of BC/WC in clinical practice. Patients and families found that BC/WC established expectations, provided clarity, and facilitated deliberation. Surgeons can learn to use BC/WC with older patients considering acute high-risk surgical interventions. Surgeons, patients, and family members endorse BC/WC as a strategy to support complex decision making. Copyright © 2017 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

Highly Concentrated Acetic Acid Poisoning: 400 Cases Reviewed

Directory of Open Access Journals (Sweden)

Konstantin Brusin

2012-12-01

Full Text Available Background: Caustic substance ingestion is known for causing a wide array of gastrointestinal and systemic complications. In Russia, ingestion of acetic acid is a major problem which annually affects 11.2 per 100,000 individuals. The objective of this study was to report and analyze main complications and outcomes of patients with 70% concentrated acetic acid poisoning. Methods: This was a retrospective study of patients with acetic acid ingestion who were treated at Sverdlovsk Regional Poisoning Treatment Center during 2006 to 2012. GI mucosal injury of each patient was assessed with endoscopy according to Zargar’s scale. Data analysis was performed to analyze the predictors of stricture formation and mortality. Results: A total of 400 patients with median age of 47 yr were included. GI injury grade I was found in 66 cases (16.5%, IIa in 117 (29.3%, IIb in 120 (30%, IIIa in 27 (16.7% and IIIb in 70 (17.5%. 11% of patients developed strictures and overall mortality rate was 21%. Main complications were hemolysis (55%, renal injury (35%, pneumonia (27% and bleeding during the first 3 days (27%. Predictors of mortality were age 60 to 79 years, grade IIIa and IIIb of GI injury, pneumonia, stages “I”, “F” and “L” of kidney damage according to the RIFLE scale and administration of prednisolone. Predictors of stricture formation were ingestion of over 100 mL of acetic acid and grade IIb and IIIa of GI injury. Conclusion: Highly concentrated acetic acid is still frequently ingested in Russia with a high mortality rate. Patients with higher grades of GI injury, pneumonia, renal injury and higher amount of acid ingested should be more carefully monitored as they are more susceptible to develop fatal consequences.          

Morphological, biochemical, molecular and ultrastructural changes induced by Cd toxicity in seedlings of Theobroma cacao L.

Science.gov (United States)

Castro, Andressa V; de Almeida, Alex-Alan F; Pirovani, Carlos P; Reis, Graciele S M; Almeida, Nicolle M; Mangabeira, Pedro A O

2015-05-01

Seeds from Theobroma cacao progenies derived from the self-pollination of 'Catongo'×'Catongo' and the crossing between CCN-10×SCA-6 were immersed for 24h in different Cd solutions (2; 4; 8; 16 and 32 mgL(-1)) along with the control treatment (without Cd). Shortly after, the seeds were sown in plastic tubes containing organic substrate and were grown in a greenhouse for 60 days. The treatment with Cd was observed to cause morphological, biochemical, molecular and ultrastructural changes in both progenies of T. cacao. There has been deformation in chloroplasts, nuclear chromatin condensation, and reduction in thickness of the mesophyll. As for 'Catongo'×'Catongo', a decrease in thickness of the epidermis was noted on the abaxial face. There has been increased guaiacol peroxidase activity in the roots of CCN-10×SCA-6, as well as in the''Catongo'×'Catongo' leaves. In the presence of Cd, CCN-10×SCA-6 showed increased expression of the genes associated with the biosynthesis of phytochelatin (PCS-1) and class III peroxidases (PER-1) in leaves, and metallothionein (MT2b), in roots. In 'Catongo'×'Catongo', there has been an increase in the expression of genes associated with the biosynthesis of PER-1 and cytosolic superoxide dismutase dependent on copper and zinc (Cu-Zn SODCyt) in leaves and from MT2b and PCS-1 and roots. There was higher accumulation of Cd in the aerial parts of seedlings from both progenies, whereas the most pronounced accumulation was seen in''Catongo'×'Catongo'. The increase in Cd concentration has led to lower Zn and Fe levels in both progenies. Hence, one may conclude that the different survival strategies used by CCN-10×SCA-6 made such progeny more tolerant to Cd stress when compared to''Catongo'×'Catongo'. Copyright © 2015. Published by Elsevier Inc.

Effect of chemical mixing state on the hygroscopicity and cloud nucleation properties of calcium mineral dust particles

Directory of Open Access Journals (Sweden)

R. C. Sullivan

2009-05-01

Full Text Available Atmospheric mineral dust particles can alter cloud properties and thus climate by acting as cloud condensation nuclei (CCN that form cloud droplets. The CCN activation properties of various calcium mineral dust particles were studied experimentally to investigate the consequences of field observations showing the segregation of sulphate from nitrate and chloride between individual aged Asian dust particles, and the enrichment of oxalic acid in Asian dust. Each mineral's observed apparent hygroscopicity was primarily controlled by its solubility, which determines the degree to which the mineral's intrinsic hygroscopicity can be expressed. The significant increase in hygroscopicity caused by mixing soluble hygroscopic material with insoluble mineral particles is also presented. Insoluble minerals including calcium carbonate, representing fresh unprocessed dust, and calcium sulphate, representing atmospherically processed dust, had similarly small apparent hygroscopicities. Their activation is accurately described by a deliquescence limit following the Kelvin effect and corresponded to an apparent single-hygroscopicity parameter, κ, of ~0.001. Soluble calcium chloride and calcium nitrate, representing atmospherically processed mineral dust particles, were much more hygroscopic, activating similar to ammonium sulphate with κ~0.5. Calcium oxalate monohydrate (κ=0.05 was significantly less CCN-active than oxalic acid (κ=0.3, but not as inactive as its low solubility would predict. These results indicate that the common assumption that all mineral dust particles become more hygroscopic and CCN-active after atmospheric processing should be revisited. Calcium sulphate and calcium oxalate are two realistic proxies for aged mineral dust that remain non-hygroscopic. The dust's apparent hygroscopicity will be controlled by its chemical mixing state, which is determined by its mineralogy and the chemical reaction pathways it experiences

cortisol/cortisone ratio as a valid tool of training load monitoring

Directory of Open Access Journals (Sweden)

T Bouaziz

2016-08-01

Full Text Available The effectiveness of selected physiological and perceptual measures for monitoring training load and fatigue was studied in 16 male elite rugby sevens players during a 6-week intense training block (IT and 2-week tapering (TAP. Daily training load (TL and strain (TS as well as weekly total score of fatigue (TSF were quantified respectively by the session-rating of perceived exertion (RPE method and an 8-item questionnaire. Also, testing was performed and 24 h urinary cortisol (C, cortisone (Cn, adrenaline (A and noradrenalin (NA excretion was measured before (T0 and after the IT (T1 and after the TAP (T2. The TL, TS and TSF increased during the IT and decreased during the TAP, in conjunction with a significant drop and improvement, respectively, of performance standards during the two periods. At T1, C and Cn levels increased while A and NA levels decreased, resulting in a higher C/Cn ratio and lower A/NA ratio, respectively. At T2, both C/Cn and A/NA returned to baseline values. The changes in C/Cn ratio, after the 6-week IT, were more closely related to mean TL, TS and TSF (r=0.75-0.76 vs. r=0.48-0.58, p<0.01 and to changes in the majority of performance measures than to A/NA ratio. Only the changes in C/Cn ratio after the 2-week TAP were related to mean TL, TS and TSF (r=0.61-0.68, p<0.01. The changes in hormone levels, training strain and performance standards reflected the physical and mental stressors of training, with complete recovery, as indicated by physiological homeostasis, achieved after an appropriate tapering period.

Almacenamiento del carbono en varios suelos cultivados con cacao en la provincia El Oro-Ecuador

Directory of Open Access Journals (Sweden)

Dr. C. Salomón Barrezueta-Unda

2018-04-01

Full Text Available Con el objetivo de estimar la variabilidad de carbono almacenado en suelos cultivados de cacao en la parte baja de la provincia El Oro, fueron seleccionadas al azar 30 parcelas cultivadas con cacao del tipo Nacional (n=12 tomado como modelo agrofestal y del clon de cacao CCN51 (n=18 como modelo en monocultivo, para lo cual se conformaron transeptos de 30 x 15 metros en el centro de cada parcela de donde se tomaron muestras de suelo a una profundidad de 0-30 cm a las que realizaron análisis de arena, limo y arcilla por Bouyucos, densidad aparente (Da por el método del cilindro, pH relación 1:25 con lectura en potenciómetro en laboratorio, Capacidad de intercambio catiónico (CIC con acetato de amonio pH 7, nitrógeno (N y carbono (C en un analizador elemental. Para cuantificar la cantidad de C almacenado se utilizó la profundidad del muestreo, la Da para determinar el volumen del suelo, el cual se multiplica por el C orgánico. Los resultados mostraron un predominio de la arena (>39% y el limo (>30%, con poca variabilidad en la Da con medias de 1,37 g-1 m3. La CIC fue superior en los cultivares de Nacional con 35,25 cmol (+ kg-1 al determinado en CCN51 (27,34 cmol (+ kg-1, al igual que el C orgánico (2,2% y N (0,20%. Los niveles de C almacenados fueron de 33,096 Mg de C ha-1 en CCN51 y 45,555 Mg de C ha-1 en Nacional, sin existir diferencias significativas (p=0,117. Palabras clave: Cacao Nacional, CCN51, carbono orgánico, densidad aparente.

Magnetosphere-ionosphere coupling during periods of extended high auroral activity: a case study

Directory of Open Access Journals (Sweden)

S. Liléo

2008-03-01

Full Text Available Results are presented from a case study of a plasma boundary crossing by the Cluster spacecraft during an extended period of high auroral activity. The boundary between the magnetotail lobe region of the Southern Hemisphere and the plasma sheet boundary layer, was characterized by intense electric and magnetic field variations, structured upward accelerated ion beams, narrow-scale large field-aligned Poynting fluxes directed upward away from the ionosphere, and a relatively sharp plasma density gradient. The observations are shown to be consistent with the concept of a multi-layered boundary with temporal and/or spatial variations in the different layers. H+ and O+ ion beams are seen to be accelerated upwards both by means of a field-aligned electric field and by magnetic pumping caused by large-amplitude and low-frequency electric field fluctuations. The peak energy of the ion beams may here be used as a diagnostic tool for the temporal evolution of the spatial structures, since the temporal changes occur on a time-scale shorter than the times-of-flight of the detected ion species. The case study also shows the boundary region to be mainly characterized by a coupling of the detected potential structures to the low ionosphere during the extended period of high auroral activity, as indicated by the intense field-aligned Poynting fluxes directed upward away from the ionosphere.

Smoking and high-risk mammographic parenchymal patterns: a case-control study

International Nuclear Information System (INIS)

Sala, Evis; Warren, Ruth; McCann, Jenny; Duffy, Stephen; Luben, Robert; Day, Nicholas

2000-01-01

leaner than controls. A larger percentage of cases were nulliparous, premenopausal, current hormone replacement therapy users, had a personal history of benign breast diseases, and had had a hysterectomy. A larger proportion of controls had more than three births and were current smokers. Table 2 shows the unadjusted and adjusted OR estimates for Wolfe's high-risk mammographic parenchymal patterns and smoking in the total study population and in postmenopausal women separately. Current smoking was strongly and inversely associated with high-risk patterns, after adjustment for concomitant risk factors. Relative to never smokers, current smokers were significantly less likely to have a high-risk pattern (OR 0.37, 95% CI 0.14-0.94). Similar results were obtained when the analysis was confined to postmenopausal women. Past smoking was not related to mammographic parenchymal patterns. The overall effect in postmenopausal women lost its significance when adjusted for other risk factors for P2/DY patterns that were found to be significant in the present study, although the results were still strongly suggestive. There was no interaction between cigarette smoking and body mass index. In the present study we found a strong inverse relationship between current smoking and high-risk mammographic parenchymal patterns of breast tissue as classified by Wolfe [12]. These findings are not completely unprecedented; Greendale et al [18] found a reduced risk of breast density in association with smoking, although the magnitude of the reduction was unclear. The present findings suggest that this reduction is large. Recent studies [9,10] have suggested that breast cancer risk may be reduced among current smokers. In a multicentre Italian case-control study, Braga et al [10] found that, relative to nonsmokers, current smokers had a reduced risk of breast cancer (OR 0.84, 95% CI 0.7-1.0). These findings were recently supported by Gammon et al [9], who reported that breast cancer risk in

Stability management of high speed axial flow compressor stage through axial extensions of bend skewed casing treatment

Directory of Open Access Journals (Sweden)

DilipkumarBhanudasji Alone

2016-09-01

Full Text Available This paper presents the experimental results to understand the performance of moderately loaded high speed single stage transonic axial flow compressor subjected to various configurations of axial extensions of bend skewed casing treatment with moderate porosity. The bend skewed casing treatment of 33% porosity was coupled with rectangular plenum chamber of depth equal to the slots depth. The five axial extensions of 20%, 40%, 60%, 80% and 100% were used for the experimental evaluations of compressor performance. The main objective was to identify the optimum extension of the casing treatment with reference to rotor leading edge which results in maximum stall margin improvements with minimum loss in the stage efficiency. At each axial extension the compressor performance is distinctive. The improvement in the stall margin was very significant at some axial extensions with 4%–5% penalty in the stage efficiency. The compressors stage shows recovery in terms of efficiency at lower axial extensions of 20% and 40% with increase in the peak stage efficiency. Measurements of flow parameters showed the typical behaviors at near stall flow conditions. Hot wire sensor was placed at the rotor upstream in the tip region to capture the oscillations in the inlet axial and tangential velocities at stall conditions. In the absence of casing treatment the compressor exhibit abrupt stall with very high oscillations in the inlet axial and tangential velocity of the flow. The extents of oscillations reduce with bend skewed casing treatment. Few measurements were also performed in the plenum chamber and salient results are presented in this paper.

Explanatory Resources on Energy in High School Physics Classes: A Case Study

Directory of Open Access Journals (Sweden)

María Alejandra Domínguez

2013-08-01

Full Text Available This paper examines and reflects on the explanatory resources that are used in high school physics classes for studying the topic of energy. Explanatory resources are a means of constructing and negotiating meaning. The research is an instrumental case study focusing on four years of high school physics classes on energy. The theoretical principles of sociocultural approaches and conversation analysis are taken as benchmarks for understanding how we construct and reconstruct meanings (on energy. The identification of the resources used in the process of meaning construction is of importance for understanding certain scientific phenomena addressed in the curricula. Among the resources most commonly employed to enhance explanation were definitions and the causes of phenomena. We also found that teachers’ interventions, either through verbal explanations or instructional proposals, were crucial for certain kinds of explanations and for the presence or absence of other resources associated with explanations.

Effective science teaching in a high poverty middle school: A case study

Science.gov (United States)

Meyer, Georgette Wright

This qualitative case study described the characteristics of science teachers in a high poverty urban middle school whose 2010 scores on South Carolina's Palmetto Assessment of State Standards (PASS) ranked second in the state. Data was obtained through classroom observations, open-ended interviews, school documents, and photographs taken inside the school from ten participants, who were seven science teachers, a science coach, and two administrators. Findings revealed a school culture that pursued warm and caring relationships with students while communicating high expectations for achievement, strong central leadership who communicated their vision and continuously checked for its implementation through informal conversations, frequent classroom observations, and test score analysis. A link between participants' current actions and their perception of prior personal and professional experiences was found. Participants related their classroom actions to the lives of the students outside of school, and evidenced affection for their students.

Aerosol Observing System (AOS) Handbook

Energy Technology Data Exchange (ETDEWEB)

Jefferson, A

2011-01-17

The Aerosol Observing System (AOS) is a suite of in situ surface measurements of aerosol optical and cloud-forming properties. The instruments measure aerosol properties that influence the earth’s radiative balance. The primary optical measurements are those of the aerosol scattering and absorption coefficients as a function of particle size and radiation wavelength and cloud condensation nuclei (CCN) measurements as a function of percent supersaturation. Additional measurements include those of the particle number concentration and scattering hygroscopic growth. Aerosol optical measurements are useful for calculating parameters used in radiative forcing calculations such as the aerosol single-scattering albedo, asymmetry parameter, mass scattering efficiency, and hygroscopic growth. CCN measurements are important in cloud microphysical models to predict droplet formation.

Green tea drinking, high tea temperature and esophageal cancer in high- and low-risk areas of Jiangsu Province, China: a population-based case-control study.

NARCIS (Netherlands)

Wu, M.; Liu, A.M.; Kampman, E.; Zhang, Z.F.; Veer, P. van 't; Wu, D.L.; Wang, P.H.; Yang, J.; Qin, Y.; Mu, L.N.; Kok, F.J.; Zhao, J.K.

2009-01-01

Epidemiological studies suggested drinking green tea is inversely associated with esophageal cancer but results remain inconclusive. Moreover, inconsistent observations found high temperature drinks are associated with esophageal cancer. A population-based case-control study was conducted in a

Green tea drinking, high tea temperature and esophageal cancer in high and low risk areas of Jiangsu Province, China: a population-based case-control study

NARCIS (Netherlands)

Wu, M.; Liu, A.; Kampman, E.; Zhang, Zuo-Feng; Veer, van 't P.; Wu, P.; Wang, P.; Kok, F.J.; Zhao, J.

2009-01-01

Epidemiological studies suggested drinking green tea is inversely associated with esophageal cancer but results remain inconclusive. Moreover, inconsistent observations found high temperature drinks are associated with esophageal cancer. A population-based case-control study was conducted in a

Case management for high-intensity service users: towards a relational approach to care co-ordination.

Science.gov (United States)

McEvoy, Phil; Escott, Diane; Bee, Penny

2011-01-01

This study is based on a formative evaluation of a case management service for high-intensity service users in Northern England. The evaluation had three main purposes: (i) to assess the quality of the organisational infrastructure; (ii) to obtain a better understanding of the key influences that played a role in shaping the development of the service; and (iii) to identify potential changes in practice that may help to improve the quality of service provision. The evaluation was informed by Gittell's relational co-ordination theory, which focuses upon cross-boundary working practices that facilitate task integration. The Assessment of Chronic Illness Care Survey was used to assess the organisational infrastructure and qualitative interviews with front line staff were conducted to explore the key influences that shaped the development of the service. A high level of strategic commitment and political support for integrated working was identified. However, the quality of care co-ordination was variable. The most prominent operational factor that appeared to influence the scope and quality of care co-ordination was the pattern of interaction between the case managers and their co-workers. The co-ordination of patient care was much more effective in integrated co-ordination networks. Key features included clearly defined, task focussed, relational workspaces with interactive forums where case managers could engage with co-workers in discussions about the management of interdependent care activities. In dispersed co-ordination networks with fewer relational workspaces, the case managers struggled to work as effectively. The evaluation concluded that the creation of flexible and efficient task focused relational workspaces that are systemically managed and adequately resourced could help to improve the quality of care co-ordination, particularly in dispersed networks. © 2010 Blackwell Publishing Ltd.

Case Studies of Leading Edge Small Urban High Schools. Core Academic Strategic Designs: 3. University Park Campus School

Science.gov (United States)

Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

2008-01-01

This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

A case of atypical progressive outer retinal necrosis after highly active antiretroviral therapy.

Science.gov (United States)

Woo, Se Joon; Yu, Hyeong Gon; Chung, Hum

2004-06-01

This is a report of an atypical case of progressive outer retinal necrosis (PORN) and the effect of highly active antiretroviral therapy (HAART) on the clinical course of viral retinitis in an acquired immunodeficiency syndrome (AIDS) patient. A 22-year-old male patient infected with human immunodeficiency virus (HIV) presented with unilaterally reduced visual acuity and a dense cataract. After cataract extraction, retinal lesions involving the peripheral and macular areas were found with perivascular sparing and the mud-cracked, characteristic appearance of PORN. He was diagnosed as having PORN based on clinical features and was given combined antiviral treatment. With concurrent HAART, the retinal lesions regressed, with the regression being accelerated by further treatment with intravenous acyclovir and ganciclovir. This case suggests that HAART may change the clinical course of PORN in AIDS patients by improving host immunity. PORN should be included in the differential diagnosis of acute unilateral cataract in AIDS patients.

Detection of previously undiagnosed cases of COPD in a high-risk population identified in general practice

DEFF Research Database (Denmark)

Løkke, Anders; Ulrik, Charlotte Suppli; Dahl, Ronald

2012-01-01

Background and Aim: Under-diagnosis of COPD is a widespread problem. This study aimed to identify previously undiagnosed cases of COPD in a high-risk population identified through general practice. Methods: Participating GPs (n = 241) recruited subjects with no previous diagnosis of lung disease,...

Multiple case study analysis of young women's experiences in high school engineering

Science.gov (United States)

Pollock, Meagan C.

richly describe the diversity of experiences. A multiple case study analysis, this study answers the question: How do gender, class, race, and other components of intersectionality, influence high school females' experiences in engineering? Nine young women taking a high school engineering course in a suburban high school in Central Texas during the school year 2011-2012 volunteered to participate. The students were observed in their engineering classes for half of the spring 2012 semester, with bi-weekly interviews with the students, monthly interviews with the teacher, and a single interview with a parent of each volunteer. The nine rich case studies provide us with new stories that help prevent us from narrowing the experiences of women to a single incomplete stereotype, because these young women vary across race, socioeconomic backgrounds, and sexual orientation. Although each story is unique, there are commonalities among their experiences, including family, influence, classroom environment, biases, and beliefs. By drawing from their collective experiences in high school engineering, the findings direct us toward recommendations for educators, parents, engineering curriculum developers, designers of teacher professional development, and future research to improve equity and access for every student in engineering.

Vertical Handover Algorithm for WBANs in Ubiquitous Healthcare with Quality of Service Guarantees

Directory of Open Access Journals (Sweden)

Dong Doan Van

2017-03-01

Full Text Available Recently, Wireless Body Area Networks (WBANs have become an emerging technology in healthcare, where patients are equipped withwearable and implantable body sensor nodes to gather sensory information for remote monitoring. The increasing development of coordinator devices on patients enables the internetworking of WBANs in heterogeneous wireless networks to deliver physiological information that is collected at remote terminals in a timely fashion. However, in this type of network, providing a seamless handover with a guaranteed Quality of Service (QoS, especially emergency services, is a challenging task. In this paper, we proposed an effective Multi-Attribute Decision-Making (MADM handover algorithm that guarantees seamless connectivity. A patient’s mobile devices automatically connect to the best network that fulfills the QoS requirements of different types of applications. Additionally, we integrated a Content-Centric Networking (CCN processing module into different wireless networks to reduce packet loss, enhance QoS and avoid unnecessary handovers by leveraging in-network caching to achieve efficient content dissemination for ubiquitous healthcare. Simulation results proved that our proposed approach forthe model with CCN outperforms the model without CCN and Received Signal Strength Vertical Handoff (RSS-VHD in terms of the number of handovers, enhancing QoS, packet loss, and energy efficiency.

Effects of Ocean Ecosystem on Marine Aerosol-Cloud Interaction

Directory of Open Access Journals (Sweden)

Nicholas Meskhidze

2010-01-01

Full Text Available Using satellite data for the surface ocean, aerosol optical depth (AOD, and cloud microphysical parameters, we show that statistically significant positive correlations exist between ocean ecosystem productivity, the abundance of submicron aerosols, and cloud microphysical properties over different parts of the remote oceans. The correlation coefficient for remotely sensed surface chlorophyll a concentration ([Chl-a] and liquid cloud effective radii over productive areas of the oceans varies between −0.2 and −0.6. Special attention is given to identifying (and addressing problems from correlation analysis used in the previous studies that can lead to erroneous conclusions. A new approach (using the difference between retrieved AOD and predicted sea salt aerosol optical depth, AODdiff is developed to explore causal links between ocean physical and biological systems and the abundance of cloud condensation nuclei (CCN in the remote marine atmosphere. We have found that over multiple time periods, 550 nm AODdiff (sensitive to accumulation mode aerosol, which is the prime contributor to CCN correlates well with [Chl-a] over the productive waters of the Southern Ocean. Since [Chl-a] can be used as a proxy of ocean biological productivity, our analysis demonstrates the role of ocean ecology in contributing CCN, thus shaping the microphysical properties of low-level marine clouds.

Cloud Condensation Nuclei Activity of Aerosols during GoAmazon 2014/15 Field Campaign Report

Energy Technology Data Exchange (ETDEWEB)

Wang, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Martin, S. T. [Harvard Univ., Cambridge, MA (United States); Kleinman, L. [Brookhaven National Lab. (BNL), Upton, NY (United States); Thalman, R. M. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2016-03-01

Aerosol indirect effects, which represent the impact of aerosols on climate through influencing the properties of clouds, remain one of the main uncertainties in climate predictions (Stocker et al. 2013). Reducing this large uncertainty requires both improved understanding and representation of aerosol properties and processes in climate models, including the cloud activation properties of aerosols. The Atmospheric System Research (ASR) science program plan of January 2010 states that: “A key requirement for simulating aerosol-cloud interactions is the ability to calculate cloud condensation nuclei and ice nuclei (CCN and IN, respectively) concentrations as a function of supersaturation from the chemical and microphysical properties of the aerosol.” The Observations and Modeling of the Green Ocean Amazon (GoAmazon 2014/15) study seeks to understand how aerosol and cloud life cycles are influenced by pollutant outflow from a tropical megacity (Manaus)—in particular, the differences in cloud-aerosol-precipitation interactions between polluted and pristine conditions. One key question of GoAmazon2014/5 is: “What is the influence of the Manaus pollution plume on the cloud condensation nuclei (CCN) activities of the aerosol particles and the secondary organic material in the particles?” To address this question, we measured size-resolved CCN spectra, a critical measurement for GoAmazon2014/5.

Rac inhibition reverses the phenotype of fibrotic fibroblasts.

Directory of Open Access Journals (Sweden)

Shi-wen Xu

Full Text Available BACKGROUND: Fibrosis, the excessive deposition of scar tissue by fibroblasts, is one of the largest groups of diseases for which there is no therapy. Fibroblasts from lesional areas of scleroderma patients possess elevated abilities to contract matrix and produce alpha-smooth muscle actin (alpha-SMA, type I collagen and CCN2 (connective tissue growth factor, CTGF. The basis for this phenomenon is poorly understood, and is a necessary prerequisite for developing novel, rational anti-fibrotic strategies. METHODS AND FINDINGS: Compared to healthy skin fibroblasts, dermal fibroblasts cultured from lesional areas of scleroderma (SSc patients possess elevated Rac activity. NSC23766, a Rac inhibitor, suppressed the persistent fibrotic phenotype of lesional SSc fibroblasts. NSC23766 caused a decrease in migration on and contraction of matrix, and alpha-SMA, type I collagen and CCN2 mRNA and protein expression. SSc fibroblasts possessed elevated Akt phosphorylation, which was also blocked by NSC23766. Overexpression of rac1 in normal fibroblasts induced matrix contraction and alpha-SMA, type I collagen and CCN2 mRNA and protein expression. Rac1 activity was blocked by PI3kinase/Akt inhibition. Basal fibroblast activity was not affected by NSC23766. CONCLUSION: Rac inhibition may be considered as a novel treatment for the fibrosis observed in SSc.

Low-dimensional compounds containing cyanide groups. XXV. Synthesis, spectroscopic properties and crystal structures of two ionic iron(II) complexes with tricyanomethanide: tris(1,10-phenanthroline-κ(2)N,N')iron(II) bis(tricyanomethanide) and tris(2,2'-bipyridine-κ(2)N,N')iron(II) bis(tricyanomethanide) sesquihydrate.

Science.gov (United States)

Potočňák, Ivan; Váhovská, Lucia; Herich, Peter

2014-05-01

Two new diamagnetic coordination compounds, [Fe(phen)3][C(CN)3]2, (I), and [Fe(bpy)3][C(CN)3]2·1.5H2O, (II), have been synthesized and characterized by single-crystal X-ray diffraction analysis, and IR and UV-Vis spectroscopy (phen is 1,10-phenanthroline, C12H8N2, and bpy is 2,2'-bipyridine, C10H8N2). Both compounds are ionic with distorted octahedral [Fe(phen)3](2+) or [Fe(bpy)3](2+) complex cations, with average Fe-N distances of 1.977 (2) and 1.971 (3) Å, respectively, and two uncoordinated planar tricyanomethanide, or [C(CN)3](-), counter-anions balancing the positive charges of the cations. Solvent water molecules and tcm anions in (II) are linked via O-H...N hydrogen bonds into negatively charged layers and the interlayer space is filled by [Fe(bpy)3](2+) cations. The structures of (I) and (II) are stabilized by π-π interactions between the stacked aromatic rings of the phen ligands of two adjacent cations and by O-H...N hydrogen bonds, respectively, and also by π-π stacking interactions between phen and tcm units in (I).

PRODUÇÃO DO CACAUEIRO SUBMETIDO A DIFERENTES LÂMINAS DE IRRIGAÇÃO E DOSES DE NITROGÊNIO

Directory of Open Access Journals (Sweden)

ROGER LUIZ DA SILVA ALMEIDA

2014-01-01

Full Text Available The aim of this study was to analyze the physical characteristics of the fruits of cocoa and co- coa producing clonal CCN - 51 submitted to irrigation and nitrogen fertigation applied in semi - arid of Bahia in an experiment conducted in the field on the property in Vale do Sol, Jequié, BA. The statistical experimental design was randomized blocks in a 4x4 factorial with treatments consisting of the sheets of water (L1 = 1146.35 mm, L2 = 1335.66 mm 1525.58 mm = L3, L4 = 1717.58 mm and the nitrogen (N1 = 249.3 kg ha - 1 , N2 = 307.2 kg ha - 1 , N3 = 365.0 kg ha - 1 , N4 = 422.9 kg ha - 1 , with four replications. Nitrogen doses and the in- teraction between them with water slides positively influenced the number of seeds per fruit, number of fruits per plant and weight of almonds per fruit; water slides influenced the number of fruits per plant clonal cacao CCN - 51. The water slides, nitrogen and the interaction between these positively influenced the production of dry almonds of cocoa clonal CCN - 51. Treatment L3 N3 showed higher productivity of cocoa almonds for sale with 1025.69 kg ha - 1 .

COPD case finding by spirometry in high-risk customers of urban community pharmacies: a pilot study.

Science.gov (United States)

Castillo, D; Guayta, R; Giner, J; Burgos, F; Capdevila, C; Soriano, J B; Barau, M; Casan, P

2009-06-01

COPD case finding is currently recommended at primary and tertiary care levels only. To evaluate the feasibility of a community pharmacy program for COPD case finding in high-risk customers by means of spirometry. Pilot cross-sectional descriptive study in 13 urban community pharmacies in Barcelona, Spain, from April to May 2007. Customers >40 years old with respiratory symptoms and/or a history of smoking were invited to participate in the study during pharmacists' routine work shifts. High-risk customers were identified by means of a 5-item COPD screening questionnaire based on criteria of the Global Initiative for Chronic Obstructive Lung Disease, and were invited to perform spirometry accordingly. Those with an FEV(1)/FVC ratio less than 0.70 were referred to the hospital for a repeat spirometry. Of the 161 pharmacy customers studied, 100 (62%) scored 3 or more items in the COPD screening questionnaire, and after spirometry, 21 (24%) had an FEV(1)/FVC ratiocustomers of urban community pharmacies is feasible. Similarly to primary care practitioners, pharmacists have access to high-risk, middle-aged subjects who have never been tested for COPD. Pharmacists can help with early detection of COPD if they are correctly trained.

High troposphere O3 filament at mid-latitude: a BORTAS campaign case study

Science.gov (United States)

Aruffo, Eleonora; Peterson, David; Di Carlo, Piero; Biancofiore, Fabio; Busilacchio, Marcella; Dari Salisburgo, Cesare; Giammaria, Franco; Bauguitte, Stephane; Lee, James; Moller, Sarah; Hopkins, James; Punjabi, Shalini; Lewis, Alistair C.; Palmer, Paul; Hyer, Edward

2016-04-01

During a flight (B625, 24 July 2011) of the BORTAS campaign (BOReal forest fires on Tropospheric oxidants over the Atlantic using Aircraft and Satellites, Nova Scotia, Canada, July-August 2011), an increase in the ozone (O3) concentrations has been observed at high altitude (about 7.5 Km a.s.l.) correlated with a significant growth of total peroxy nitrates (∑PNs), CO, NO2, NOy, black carbon (BC), isoprene and other species. We will illustrate the data analysis, the Hysplit back trajectories calculation and the analysis of the meteorological/physical conditions occurred during this case study in order to demonstrate that the O3 filament measured at high altitude over the Atlantic Ocean (between Nova Scotia and the Gulf of St. Lawrence) is a consequence of boreal biomass burning fires.

Should all suspected tuberculosis cases in high income countries be tested with GeneXpert?

Science.gov (United States)

Vella, Venanzio; Broda, Agnieszka; Drobniewski, Francis

2018-05-01

In countries with a low incidence of multidrug-resistant tuberculosis (MDR-TB), universal testing with GeneXpert might not be always cost-effective. This study provides hospital managers in low MDR-TB incidence countries with criteria on when decentralised universal GeneXpert testing would make sense. The alternatives taken into consideration include: universal microbiological culture and drug susceptibility testing (DST) only (comparator); as above but with concurrent centralized GeneXpert in a referral laboratory vs a decentralized GeneXpert system in every hospital to test smear-positive cases only; as above but testing all samples with GeneXpert regardless of smear status. The parameters were from the national TB statistics for England and from a systematic review. Decentralised GeneXpert to test any suspected TB case was the most cost-effective option when 6% or more TB patients belonged to the high-risk group, defined as previous TB diagnosis and or being born in countries with a high MDR-TB incidence. Hospital managers in England and other low MDR-TB incidence countries could use these findings to decide when to invest in GeneXpert or other molecular diagnostics with similar performance criteria for TB diagnostics. Copyright © 2017 Elsevier Ltd. All rights reserved.

Using risk-tracing snowball approach to increase HIV case detection among high-risk populations in Cambodia: an intervention study.

Science.gov (United States)

Chhim, Srean; Macom, John; Pav, Chettana; Nim, Nirada; Yun, Phearun; Seng, Sopheap; Chhim, Kolab; Tuot, Sovannary; Yi, Siyan

2017-10-18

Early HIV diagnosis and initiation onto antiretroviral therapy may prevent ongoing spread of HIV. Risk Tracing Snowball Approach (RTSA) has been shown to be effective in detecting new HIV cases in other settings. The main objective of this study is to evaluate the effectiveness of RTSA in increasing the rate of newly identified HIV cases among high-risk populations. Our second objective was to evaluate the effectiveness of RTSA, as compared to the walk-in group, in increasing the number of HIV tests and early case detection. This study was conducted from April 1 to September 30, 2016 at two NGO clinics in Phnom Penh, Cambodia. Respondent driven sampling method was adapted to develop RTSA to reach high-risk populations, including key populations and the general population who have social connections with key populations. Bivariate and multivariate logistic regression analyses were conducted. During the implementation period, 721 clients walked in for HIV testing (walk-in group), and all were invited to be seeds. Of the invited clients, 36.6% agreed to serve as seeds. Throughout the implementation, 6195 coupons were distributed to seeds or recruiters, and resulted in 1572 clients visiting the two clinics with coupons (RTSA group), for a coupon return rate of 25.3%. The rate of newly identified HIV cases among the RTSA group was significantly lower compared to that in walk-in group. However, the highest number of newly identified HIV cases was found during the implementation period, compared to both pre- and post-implementation period. Although statistically not significant, the mean CD4 count of newly identified HIV cases detected through RTSA was almost 200 cells/mm3 higher than that in the walk-in group. Although the rate of newly identified HIV cases among the RTSA group was lower than that in the walk-in group, the inclusion of RTSA in addition to the traditional walk-in method boosted new HIV case detection in the two participating clinics. A higher mean CD4

Magnetosphere-ionosphere coupling during periods of extended high auroral activity: a case study

Directory of Open Access Journals (Sweden)

S. Liléo

2008-03-01

Full Text Available Results are presented from a case study of a plasma boundary crossing by the Cluster spacecraft during an extended period of high auroral activity. The boundary between the magnetotail lobe region of the Southern Hemisphere and the plasma sheet boundary layer, was characterized by intense electric and magnetic field variations, structured upward accelerated ion beams, narrow-scale large field-aligned Poynting fluxes directed upward away from the ionosphere, and a relatively sharp plasma density gradient.

The observations are shown to be consistent with the concept of a multi-layered boundary with temporal and/or spatial variations in the different layers. H⁺ and O⁺ ion beams are seen to be accelerated upwards both by means of a field-aligned electric field and by magnetic pumping caused by large-amplitude and low-frequency electric field fluctuations. The peak energy of the ion beams may here be used as a diagnostic tool for the temporal evolution of the spatial structures, since the temporal changes occur on a time-scale shorter than the times-of-flight of the detected ion species.

The case study also shows the boundary region to be mainly characterized by a coupling of the detected potential structures to the low ionosphere during the extended period of high auroral activity, as indicated by the intense field-aligned Poynting fluxes directed upward away from the ionosphere.

Adverse effect of high migration stress on mental health during pregnancy: a case report.

Science.gov (United States)

Lecompte, Vanessa; Richard-Fortier, Zoé; Rousseau, Cécile

2017-02-01

Despite empirical evidence on the numerous consequences associated with high migration stress and mental health problems during pregnancy, a psychosocial stress assessment is rarely done, leaving it largely unaddressed. This case illustration sheds light on the common multiple risk factors related to migration stress that have to be taken into consideration when addressing perinatal mental health, and highlights the importance of obstetric appointments as a unique opportunity to assess psychosocial stress and mobilize interdisciplinary interventions.

Adoption of New Technologies in a Highly Uncertain Environment: The Case of Egyptian Public Banks

Science.gov (United States)

Khedr, A.; Borgman, H.

What is the relation between the process of adopting new technologies, and its impact on business value, in situations of high internal and external uncertainty? Whereas technology adoption is generally fairly well understood, the models do not seem to hold in situations of high uncertainty. The aim of this paper is to investigate the impact of this uncertainty, using a case study on the introduction of a new technology in a large Egyptian public bank. After exploring the most relevant uncertainty factors and their impact on the adoption process, the paper ends with a general discussion and conclusion.

Fantasievoll / Giselher Schubert

Index Scriptorium Estoniae

Schubert, Giselher

2008-01-01

Arvustus: Kristjan Järvi. Symphony Orchestra of Norrlands Opera. To the new world and beyond. Igor Stravinsky / Paul Hindemith. Diepholz (Germany) : CCn'C, 2006. Heliplaadil dirigeerib Kristjan Järvi

A Case Study of Co-Teaching in an Inclusive Secondary High-Stakes World History I Classroom

Science.gov (United States)

van Hover, Stephanie; Hicks, David; Sayeski, Kristin

2012-01-01

In order to provide increasing support for students with disabilities in inclusive classrooms in high-stakes testing contexts, some schools have implemented co-teaching models. This qualitative case study explores how 1 special education teacher (Anna) and 1 general education history teacher (John) make sense of working together in an inclusive…

[High-grade small bowel angiosarcoma associated with angiosarcomatosis: a case report].

Science.gov (United States)

Chahbouni, Sanae; Barnoud, Raphaëlle; Watkin, Emmanuel; Devouassoux-Shisheboran, Mojgan

2011-08-01

Angiosarcoma is a rare soft-tissue neoplasm occurring most often in the skin and the subcutaneous tissues and very rarely in the gastrointestinal tract. We report a case of a 25-year-old woman who presented with a small intestinal angiosarcoma associated with angiosarcomatosis. The diagnosis was established on surgical intestinal resection, that showed a high-grade angiosarcoma with epithelioid component and foci of agressive form of hemangioendothelioma. Immunohistochemical study revealed tumour cell positivity with endothelial markers CD31 and factor VIII whereas CD34 and epithelial markers were negative. The tumour displayed KIT (CD117) immunoreactivity without KIT or PDGFRA mutation on molecular analysis. Clinical and pathological features as well as differential diagnosis of this rare entity in gastrointestinal tract are discussed. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Bevacizumab in High Grade Gliomas: A Case Report and Review of the Literature

International Nuclear Information System (INIS)

Balana, Carme; Cardona, Andres Felipe

2007-01-01

Patients with anaplastic astrocytoma or glioblastoma generally have adverse prognosis. Currently, standard treatment for high grade glial cell tumors consists of the concomitant use of radiotherapy and Themozolamide, followed by six months with the alkilant. However, subjects diagnosed with novo or recurrent tumors have overall survival rates from 3 to 15 months. Multiple chemotherapeutic and biological agents have been used to control progression, with no improvement in survival rates. New medication is being developed aimed at molecular targets such as the endothelial growth factor which can be regulated by, among others, Bevacizumab (BEV). Recent results from phase 11 trials combining BEV and Irinotecan (CPT-11) in patients with high grade gliomas revealed improved response rates, as well as disease free and overall survival rates. The case of a female with recurrent glioblastoma who achieved complete response after initiating BEV/CPT- 11 is presented

A Study of Direct and Cloud-Mediated Radiative Forcing of Climate Due to Aerosols

Science.gov (United States)

Yu, Shao-Cai

1999-01-01

average CCN concentrations at 0.3% and 1% supersaturations ranged from 0.3 to 160/cubic cm and from 4 to 168/cubic cm, respectively, during the period from 17 January to 26 February, 1994. New evidence for substantial and definitive CCN enhancement near and within cloud has been observed at Mt. Mitchell, North Carolina. The results show that the average monthly CCN concentrations were 460 +/- 217, 386 +/- 286, 429 +/- 228 and 238 +/- 134/cubic cm for in-cloud, overcast, clear and rainy conditions, respectively. The typical CCN spectra show that there were a lot of small CCN produced and the ion concentrations (especially H+ and SO4 2-) were very high during the CCN enhancement period. The significantly positive correlation between black carbon (BC) and CCN at 1% supersaturation indicates that a percentage of the BC measured at the site may be in the form of an internal mixture and participated in the formation of CCN.

Global importation and population risk factors for measles in New Zealand: a case study for highly immunized populations.

Science.gov (United States)

Hayman, D T S; Marshall, J C; French, N P; Carpenter, T E; Roberts, M G; Kiedrzynski, T

2017-07-01

As endemic measles is eliminated through immunization, countries must determine the risk factors for the importation of measles into highly immunized populations to target control measures. Despite eliminating endemic measles, New Zealand suffers from outbreaks after introductions from abroad, enabling us to use it as a model for measles introduction risk. We used a generalized linear model to analyze risk factors for 1137 measles cases from 2007 to June 2014, provide estimates of national immunity levels, and model measles importation risk. People of European ethnicity made up the majority of measles cases. Age is a positive risk factor, particularly 0-2-year-olds and 5-17-year-old Europeans, along with increased wealth. Pacific islanders were also at greater risk, but due to 0-2-year-old cases. Despite recent high measles, mumps, and rubella vaccine immunization coverage, overall population immunity against measles remains ~90% and is lower in people born between 1982 and 2005. Greatest measles importation risk is during December, and countries predicted to be sources have historical connections and highest travel rates (Australia and UK), followed by Asian countries with high travel rates and higher measles incidences. Our results suggest measles importation due to travel is seeding measles outbreaks, and immunization levels are insufficient to continue to prevent outbreaks because of heterogeneous immunity in the population, leaving particular age groups at risk.

Low to high performance recycled cementitious materials: case studies

OpenAIRE

Etxeberria Larrañaga, Miren

2015-01-01

In this work, four real case studies using concrete produced with recycled aggregates are described. The four real cases carried out in Barcelona are: 1) Pavement filling with control low strength material (CLSM) employing fine recycled aggregates, 2) pervious recycled aggregate concrete employing coarse mixed recycled aggregates in the works undertaken at Cervantes park; 3) Concrete blocks produced employing recycled and slag aggregates as well as sea water for a new breakwater dyke and 4) R...

A simple parameterization of aerosol emissions in RAMS

Science.gov (United States)

Letcher, Theodore

Throughout the past decade, a high degree of attention has been focused on determining the microphysical impact of anthropogenically enhanced concentrations of Cloud Condensation Nuclei (CCN) on orographic snowfall in the mountains of the western United States. This area has garnered a lot of attention due to the implications this effect may have on local water resource distribution within the Region. Recent advances in computing power and the development of highly advanced microphysical schemes within numerical models have provided an estimation of the sensitivity that orographic snowfall has to changes in atmospheric CCN concentrations. However, what is still lacking is a coupling between these advanced microphysical schemes and a real-world representation of CCN sources. Previously, an attempt to representation the heterogeneous evolution of aerosol was made by coupling three-dimensional aerosol output from the WRF Chemistry model to the Colorado State University (CSU) Regional Atmospheric Modeling System (RAMS) (Ward et al. 2011). The biggest problem associated with this scheme was the computational expense. In fact, the computational expense associated with this scheme was so high, that it was prohibitive for simulations with fine enough resolution to accurately represent microphysical processes. To improve upon this method, a new parameterization for aerosol emission was developed in such a way that it was fully contained within RAMS. Several assumptions went into generating a computationally efficient aerosol emissions parameterization in RAMS. The most notable assumption was the decision to neglect the chemical processes in formed in the formation of Secondary Aerosol (SA), and instead treat SA as primary aerosol via short-term WRF-CHEM simulations. While, SA makes up a substantial portion of the total aerosol burden (much of which is made up of organic material), the representation of this process is highly complex and highly expensive within a numerical

Methodological proposal for identification and evaluation of environmental aspects and impacts of nuclear facilities of IPEN, Sao Paulo, SP, Brazil: a case study applied to the Nuclear Fuel Center

International Nuclear Information System (INIS)

Mattos, Luis Antonio Terribile de

2013-01-01

This work presents an application of Failure Mode Effect Analysis (FMEA) to the process of identification of environmental aspects and impacts as a part of implementation and maintenance of an Environmental Management System (EMS) in accordance with the NBR ISO 14001 standard. Also, it can contribute, as a complement, to the evaluation and improvement of safety of the installation focused. The study was applied to the Nuclear Fuel Center (CCN) of Nuclear and Energy Research Institute (IPEN), situated at the Campus of University of Sao Paulo, Brazil. The CCN facility has the objective of promoting scientific research and of producing nuclear fuel elements for the IEA-R1 Research Reactor. To identify the environmental aspects of the facility activities, products, and services, a systematic data collection was carried out by means of personal interviews, documents, reports and operation data records consulting. Furthermore, the processes and their interactions, failure modes, besides their causes and effects to the environment, were identified. As a result of a careful evaluation of these causes it was possible to identify and to classify the major potential environmental impacts, in order to set up and put in practice an Environmental Management System for the installation under study. The results have demonstrated the validity of the FMEA application to nuclear facility processes, identifying environmental aspects and impacts, whose controls are critical to achieve compliance with the environmental requirements of the Integrated Management System of IPEN. It was demonstrated that the methodology used in this work is a powerful management tool for resolving issues related to the conformity with applicable regulatory and legal requirements of the Brazilian Nuclear Energy Commission (CNEN) and the Brazilian Institute of Environment (IBAMA). (author)

Spanish language generation engine to enhance the syntactic quality of AAC systems

Science.gov (United States)

Narváez A., Cristian; Sastoque H., Sebastián.; Iregui G., Marcela

2015-12-01

People with Complex Communication Needs (CCN) face difficulties to communicate their ideas, feelings and needs. Augmentative and Alternative Communication (AAC) approaches aim to provide support to enhance socialization of these individuals. However, there are many limitations in current applications related with systems operation, target scenarios and language consistency. This work presents an AAC approach to enhance produced messages by applying elements of Natural Language Generation. Specifically, a Spanish language engine, composed of a grammar ontology and a set of linguistic rules, is proposed to improve the naturalness in the communication process, when persons with CCN tell stories about their daily activities to non-disabled receivers. The assessment of the proposed method confirms the validity of the model to improve messages quality.

Quantification of effluents in the production of nuclear fuel

Energy Technology Data Exchange (ETDEWEB)

Sakai, Mayara C.C.B.; Riella, Humberto G.; Carvalho, Elita F.U. de, E-mail: mcostac@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2017-07-01

At the Instituto de Pesquisa Energéticas e Nucleares (IPEN), the Centro de Combustível Nuclear (CCN), Sao Paulo, SP, Brazil, is responsible for manufacturing fuels for the IEA-R1 reactor and, possibly, the multipurpose reactor fuels. In order to meet the demand for both reactors, the CCN developed a new plant. The production process of the fuel generates several types of effluents - containing uranium or not - being solid, liquid and gaseous with varied physical and chemical characteristics. The objective of this work is to follow the nuclear fuel production process and to identify, quantify and characterize the effluents, especially the liquid ones, to later elaborate a plan of management of these and eventually dispose in a responsible way in the environment. (author)

Corona discharge induced snow formation in a cloud chamber.

Science.gov (United States)

Ju, Jingjing; Wang, Tie-Jun; Li, Ruxin; Du, Shengzhe; Sun, Haiyi; Liu, Yonghong; Tian, Ye; Bai, Yafeng; Liu, Yaoxiang; Chen, Na; Wang, Jingwei; Wang, Cheng; Liu, Jiansheng; Chin, S L; Xu, Zhizhan

2017-09-18

Artificial rainmaking is in strong demand especially in arid regions. Traditional methods of seeding various Cloud Condensation Nuclei (CCN) into the clouds are costly and not environment friendly. Possible solutions based on ionization were proposed more than 100 years ago but there is still a lack of convincing verification or evidence. In this report, we demonstrated for the first time the condensation and precipitation (or snowfall) induced by a corona discharge inside a cloud chamber. Ionic wind was found to have played a more significant role than ions as extra CCN. In comparison with another newly emerging femtosecond laser filamentation ionization method, the snow precipitation induced by the corona discharge has about 4 orders of magnitude higher wall-plug efficiency under similar conditions.

Hemispheric aerosol vertical profiles: anthropogenic impacts on optical depth and cloud nuclei.

Science.gov (United States)

Clarke, Antony; Kapustin, Vladimir

2010-09-17

Understanding the effect of anthropogenic combustion upon aerosol optical depth (AOD), clouds, and their radiative forcing requires regionally representative aerosol profiles. In this work, we examine more than 1000 vertical profiles from 11 major airborne campaigns in the Pacific hemisphere and confirm that regional enhancements in aerosol light scattering, mass, and number are associated with carbon monoxide from combustion and can exceed values in unperturbed regions by more than one order of magnitude. Related regional increases in a proxy for cloud condensation nuclei (CCN) and AOD imply that direct and indirect aerosol radiative effects are coupled issues linked globally to aged combustion. These profiles constrain the influence of combustion on regional AOD and CCN suitable for challenging climate model performance and informing satellite retrievals.

Connective tissue growth factor (CTGF) and cancer progression.

Science.gov (United States)

Chu, Chia-Yu; Chang, Cheng-Chi; Prakash, Ekambaranellore; Kuo, Min-Liang

2008-11-01

Connective tissue growth factor (CTGF) is a member of the CCN family of secreted, matrix-associated proteins encoded by immediate early genes that play various roles in angiogenesis and tumor growth. CCN family proteins share uniform modular structure which mediates various cellular functions such as regulation of cell division, chemotaxis, apoptosis, adhesion, motility, angiogenesis, neoplastic transformation, and ion transport. Recently, CTGF expression has been shown to be associated with tumor development and progression. There is growing body of evidence that CTGF may regulate cancer cell migration, invasion, angiogenesis, and anoikis. In this review, we will highlight the influence of CTGF expression on the biological behavior and progression of various cancer cells, as well as its regulation on various types of protein signals and their mechanisms.

Coordination compounds of thorium(4) containing tris(dimethylamino)-phosphinoxide

International Nuclear Information System (INIS)

Skopenko, V.V.; Klunnik, L.A.

1983-01-01

Compounds including tris(dimethylamino)-phosphinoxide of the following composition: [ThX 4 (HMPA) 4 ] and [ThX 2 (HMPA) 4 ](BPh 4 ) 2 , where X=NCSe, N(CN) 2 =, C(CN) 3 , ONC(CN) 2 -, [C(CN) 2 C(O)NH 2 ], BPh 4 =[B(C 6 H 5 ) 4 ] - , and HMPA=OP[N(CN 3 ) 2 ] 3 are prepared by interactions of thoriUm chloride with different pseudohalogenides and sodium tetraphenylborate. Some properties of the above compoUnds are studied. Using the IR spectroscopy, the way of coordinating these compounds is determined; the X-ray crystal analysis has determined isostrUcture of compounds: [Th(NCX) 4 (HMPA) 4 ] and [ThX 2 (HMPA) 4 ](BPh 4 ) 2 , where X is Se, S

Quantification of effluents in the production of nuclear fuel

International Nuclear Information System (INIS)

Sakai, Mayara C.C.B.; Riella, Humberto G.; Carvalho, Elita F.U. de

2017-01-01

At the Instituto de Pesquisa Energéticas e Nucleares (IPEN), the Centro de Combustível Nuclear (CCN), Sao Paulo, SP, Brazil, is responsible for manufacturing fuels for the IEA-R1 reactor and, possibly, the multipurpose reactor fuels. In order to meet the demand for both reactors, the CCN developed a new plant. The production process of the fuel generates several types of effluents - containing uranium or not - being solid, liquid and gaseous with varied physical and chemical characteristics. The objective of this work is to follow the nuclear fuel production process and to identify, quantify and characterize the effluents, especially the liquid ones, to later elaborate a plan of management of these and eventually dispose in a responsible way in the environment. (author)

Case Studies of Leading Edge Small Urban High Schools. Relevance Strategic Designs: 5. Life Academy of Health and Bioscience

Science.gov (United States)

Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

2008-01-01

This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

Case Studies of Leading Edge Small Urban High Schools. Core Academic Strategic Designs: 1. Academy of the Pacific Rim

Science.gov (United States)

Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

2008-01-01

This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

The application of paravertebral block in high-risk patient with cardiorespiratory, liver and kidney problems: a case report

OpenAIRE

ŽUPČIĆ, MIROSLAV; GRAF ŽUPČIĆ, SANDRA; BRUNDULA, ANA; ZRINJŠČAK, IVA KOREČIĆ; PERŠEC, JASMINKA; HUSEDŽINOVIĆ1, INO

2015-01-01

Background and Purpose: We present a case report of a patient of the American Society of Anesthesiologists’ (ASA) IV scheduled for a modified radical mastectomy (MRM) due to malignant disease. The patient was a high risk patient for general anesthesia and we opted for the application of unilateral paravertebral block on several levels. Case report. A 86-year-old female was scheduled for a surgery due to recurrent malignant process on her right breast. She was an ASA IV patie...

Leadership to Build a Democratic Community within School: A Case Study of Two Korean High Schools

Science.gov (United States)

Kang, Young Taek; Printy, Susan

2009-01-01

This article aims to explore how democratic community is manifest in schools in Korea. It also tries to examine how leadership, specifically transformational leadership, functions in shaping a democratic community within a school. Toward this aim, we have conducted a case study of two religious high schools in Korea. Based on the findings from the…

A case report of treating a high-risk gestational trophoblastic disease (GTD

Directory of Open Access Journals (Sweden)

Zhi Hao Liew

2017-12-01

Full Text Available Background: GTD developing after a normal pregnancy is reported in 25% of patients and it is usually choriocarcinoma. It occurs in approximately 5 per 100,000 pregnancies in Southeast Asia. Case: A 34 year-old Malay lady, gravida 4 para 4+0 presented with vaginal bleeding in two weeks after the delivery of her fourth child who was born as full term through LSCS. She admitted to hospital and underwent Suction and curettage. The histopathology came back as choriocarcinoma. On post-op day 7, she developed massive hemoperitoneum due to uterine perforation caused by tumour rupture. Therefore, total abdominal hysterectomy was performed. Post-surgery serum beta hCG was 209,320 IU/L. Thyroid function test was normal. Histopathology examination revealed choriocarcinoma at the fundus with haemorrhagic necrotic areas, infiltrating myometrial wall and right fallopian tube stump with serosal breach. CT imaging showed normal brain and multiple bilateral lung nodules in upper and lower lobes. She was given first cycle of EMA-CO (Etoposide, Methotrexate, Actinomycin D, Vincristine, Cyclophosphamid in view of high-risk choriocarcinoma with lungs metastasis, stage III with WHO prognostic scoring 11. Her pre-chemotherapy beta hCG was 263,753 IU/L which gradually went down and became less than 0.1 after cycle-5. CT scan was also normal. After that, another two more cycles of chemotherapy were proceeded. Therefore, she has completed seven cycles of chemotherapy in March 2016. She has been monitored under oncology follow-up for one year. Monthly βhCG was always normal until now without signs and symptoms of recurrence. Conclusion: Generally, high-risk GTDs are resistant to single agent chemotherapy and multiple chemotherapy regimens are necessary. Although this patient is a case of choriocarcinoma having high risk features, such as antecedent full-term pregnancy and pre-treatment beta-hCG of 263,753 IU/L (more than 100,000, she gained complete remission after seven

Examining Model Atmospheric Particles Inside and Out

Science.gov (United States)

Wingen, L. M.; Zhao, Y.; Fairhurst, M. C.; Perraud, V. M.; Ezell, M. J.; Finlayson-Pitts, B. J.

2017-12-01

Atmospheric particles scatter incoming solar radiation and act as cloud condensation nuclei (CCN), thereby directly and indirectly affecting the earth's radiative balance and reducing visibility. These atmospheric particles may not be uniform in composition. Differences in the composition of a particle's outer surface from its core can arise during particle growth, (photo)chemical aging, and exchange of species with the gas phase. The nature of the surface on a molecular level is expected to impact growth mechanisms as well as their ability to act as CCN. Model laboratory particle systems are explored using direct analysis in real time-mass spectrometry (DART-MS), which is sensitive to surface composition, and contrasted with average composition measurements using high resolution, time-of-flight aerosol mass spectrometry (HR-ToF-AMS). Results include studies of the heterogeneous reactions of amines with solid dicarboxylic acid particles, which are shown to generate aminium dicarboxylate salts at the particle surface, leaving an unreacted core. Combination of both mass spectrometric techniques reveals a trend in reactivity of C3-C7 dicarboxylic acids with amines and allows calculation of the DART probe depth into the particles. The results of studies on additional model systems that are currently being explored will also be reported.

Competition for water vapour results in suppression of ice formation in mixed-phase clouds

Directory of Open Access Journals (Sweden)

E. L. Simpson

2018-05-01

Full Text Available The formation of ice in clouds can initiate precipitation and influence a cloud's reflectivity and lifetime, affecting climate to a highly uncertain degree. Nucleation of ice at elevated temperatures requires an ice nucleating particle (INP, which results in so-called heterogeneous freezing. Previously reported measurements for the ability of a particle to nucleate ice have been made in the absence of other aerosol which will act as cloud condensation nuclei (CCN and are ubiquitous in the atmosphere. Here we show that CCN can outcompete INPs for available water vapour thus suppressing ice formation, which has the potential to significantly affect the Earth's radiation budget. The magnitude of this suppression is shown to be dependent on the mass of condensed water required for freezing. Here we show that ice formation in a state-of-the-art cloud parcel model is strongly dependent on the criteria for heterogeneous freezing selected from those previously hypothesised. We have developed an alternative criteria which agrees well with observations from cloud chamber experiments. This study demonstrates the dominant role that competition for water vapour can play in ice formation, highlighting both a need for clarity in the requirements for heterogeneous freezing and for measurements under atmospherically appropriate conditions.

Competition for water vapour results in suppression of ice formation in mixed-phase clouds

Science.gov (United States)

Simpson, Emma L.; Connolly, Paul J.; McFiggans, Gordon

2018-05-01

The formation of ice in clouds can initiate precipitation and influence a cloud's reflectivity and lifetime, affecting climate to a highly uncertain degree. Nucleation of ice at elevated temperatures requires an ice nucleating particle (INP), which results in so-called heterogeneous freezing. Previously reported measurements for the ability of a particle to nucleate ice have been made in the absence of other aerosol which will act as cloud condensation nuclei (CCN) and are ubiquitous in the atmosphere. Here we show that CCN can outcompete INPs for available water vapour thus suppressing ice formation, which has the potential to significantly affect the Earth's radiation budget. The magnitude of this suppression is shown to be dependent on the mass of condensed water required for freezing. Here we show that ice formation in a state-of-the-art cloud parcel model is strongly dependent on the criteria for heterogeneous freezing selected from those previously hypothesised. We have developed an alternative criteria which agrees well with observations from cloud chamber experiments. This study demonstrates the dominant role that competition for water vapour can play in ice formation, highlighting both a need for clarity in the requirements for heterogeneous freezing and for measurements under atmospherically appropriate conditions.

High summertime aerosol organic functional group concentrations from marine and seabird sources at Ross Island, Antarctica, during AWARE

Directory of Open Access Journals (Sweden)

J. Liu

2018-06-01

Full Text Available Observations of the organic components of the natural aerosol are scarce in Antarctica, which limits our understanding of natural aerosols and their connection to seasonal and spatial patterns of cloud albedo in the region. From November 2015 to December 2016, the ARM West Antarctic Radiation Experiment (AWARE measured submicron aerosol properties near McMurdo Station at the southern tip of Ross Island. Submicron organic mass (OM, particle number, and cloud condensation nuclei concentrations were higher in summer than other seasons. The measurements included a range of compositions and concentrations that likely reflected both local anthropogenic emissions and natural background sources. We isolated the natural organic components by separating a natural factor and a local combustion factor. The natural OM was 150 times higher in summer than in winter. The local anthropogenic emissions were not hygroscopic and had little contribution to the CCN concentrations. Natural sources that included marine sea spray and seabird emissions contributed 56 % OM in summer but only 3 % in winter. The natural OM had high hydroxyl group fraction (55 %, 6 % alkane, and 6 % amine group mass, consistent with marine organic composition. In addition, the Fourier transform infrared (FTIR spectra showed the natural sources of organic aerosol were characterized by amide group absorption, which may be from seabird populations. Carboxylic acid group contributions were high in summer and associated with natural sources, likely forming by secondary reactions.

Successful Treatment of Rubral Tremor by High-Dose Trihexyphenidyl: A Case Report

Directory of Open Access Journals (Sweden)

Li-Min Liou

2006-03-01

Full Text Available A 24-year-old male suffered from acute-onset right-sided hemiparesis, dysarthria, and ophthalmoplegia in February 2001. Brain magnetic resonance imaging revealed a cavernous angioma with hemorrhage over the left thalamus. Moreover, some rhythmic, coarse, low-frequency (2-3 Hz oscillation over the right wrist and elbow was noted 1 month later. Action tremor was more predominant than resting tremor. Rubral tremor was diagnosed on the basis of the clinical presentation and tremography analysis. Rubral tremor is not unusual, and pharmacotherapy is nearly always ineffective in clinical practice. Deep brain stimulation, thalamotomy, and pallidotomy are all considered effective according to recent research. However, they are either very expensive or invasive, and involve surgical risks. In our patient, we tried valproate, clonazepam, and verapamil one after another, but all in vain. Finally, titration of trihexyphenidyl provided significant benefit. The tremor was successfully controlled by a single high daily dose of trihexyphenidyl (38 mg without severe or uncomfortable side effects. Here, we report a case of successful monotherapy of rubral tremor with high-dose trihexyphenidyl.

High fidelity case-based simulation debriefing: everything you need to know.

Science.gov (United States)

Hart, Danielle; McNeil, Mary Ann; Griswold-Theodorson, Sharon; Bhatia, Kriti; Joing, Scott

2012-09-01

In this 30-minute talk, the authors take an in-depth look at how to debrief high-fidelity case-based simulation sessions, including discussion on debriefing theory, goals, approaches, and structure, as well as ways to create a supportive and safe learning environment, resulting in successful small group learning and self-reflection. Emphasis is placed on the "debriefing with good judgment" approach. Video clips of sample debriefing attempts, highlighting the "dos and don'ts" of simulation debriefing, are included. The goal of this talk is to provide you with the necessary tools and information to develop a successful and effective debriefing approach. There is a bibliography and a quick reference guide in Data Supplements S1 and S2 (available as supporting information in the online version of this paper). © 2012 by the Society for Academic Emergency Medicine.

Outsourcing a High Speed Internet Access Project: An Information Technology Class Case Study in Three Parts

Science.gov (United States)

Platt, Richard G.; Carper, William B.; McCool, Michael

2010-01-01

In early 2004, the Hilton Hotels Corporation (HHC) required that all of its hotels (both owned and franchised) install high-speed Internet access (HSIA) in all of their rooms by June 2004. This case focuses on how one of its franchise properties located on the northern gulf coast of Florida (the Hilton Sandestin Beach Golf Resort &…

Passive fire protection in high density village (case study, Bustaman Semarang)

Science.gov (United States)

Sukawi, Sukawi; Wahyu Firmandhani, Satriya; Hardiman, Gagoek

2017-12-01

Fire hazard is the disaster that always has an unpredictable process of coming. When it comes, its level scope and the magnitude of the effects cannot be predicted. Dense settlements especially in big cities, among others Bustaman Kampong Semarang never escape from physical problems such as flooding and wildfire. If both are compared in dense settlements scope, so that, wild fire is the most potentially catastrophic. It is necessary to do a research on passive fire protection in a village of high density city such as Bustaman. Qualitative research was conducted using descriptive method to conduct observations and interviews in the Bustaman. Bustaman as a high density village, with narrow roads and dense rows of houses. The terraced buildings are also encountered, and found many buildings use combustible material. That environmental conditions can facilitate the propagation of flames in case of fire. To improve the established Bustaman's environment, in terms of the application of passive fire protection systems, it is recommended to utilize the road as the dividing buildings. Need to build the separation wall fireproof in every each series in several units of too long buildings and attempted open space procurement that separates rows of buildings that are too long, and also the replacement of combustible material with a material that is more incombustible.

RFID-enabled traceability system for consignment and high value products: a case study in the healthcare sector.