Science.gov

Sample records for right-ascension interval 7h

  1. Search for first harmonic modulation in the right ascension distribution of cosmic rays detected at the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    Pierre Auger Collaboration; Abreu, P.; Aglietta, M.; Ahn, E. J.; Albuquerque, I. F. M.; Allard, D.; Allekotte, I.; Allen, J.; Allison, P.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Ambrosio, M.; Aminaei, A.; Anchordoqui, L.; Andringa, S.; Antičić, T.; Aramo, C.; Arganda, E.; Arqueros, F.; Asorey, H.; Assis, P.; Aublin, J.; Ave, M.; Avenier, M.; Avila, G.; Bäcker, T.; Balzer, M.; Barber, K. B.; Barbosa, A. F.; Bardenet, R.; Barroso, S. L. C.; Baughman, B.; Beatty, J. J.; Becker, B. R.; Becker, K. H.; Bellido, J. A.; Benzvi, S.; Berat, C.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blanco, F.; Blanco, M.; Bleve, C.; Blümer, H.; Boháčová, M.; Boncioli, D.; Bonifazi, C.; Bonino, R.; Borodai, N.; Brack, J.; Brogueira, P.; Brown, W. C.; Bruijn, R.; Buchholz, P.; Bueno, A.; Burton, R. E.; Caballero-Mora, K. S.; Caramete, L.; Caruso, R.; Castellina, A.; Cataldi, G.; Cazon, L.; Cester, R.; Chauvin, J.; Chiavassa, A.; Chinellato, J. A.; Chou, A.; Chudoba, J.; Clay, R. W.; Coluccia, M. R.; Conceição, R.; Contreras, F.; Cook, H.; Cooper, M. J.; Coppens, J.; Cordier, A.; Cotti, U.; Coutu, S.; Covault, C. E.; Creusot, A.; Criss, A.; Cronin, J.; Curutiu, A.; Dagoret-Campagne, S.; Dallier, R.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; de Domenico, M.; de Donato, C.; de Jong, S. J.; de La Vega, G.; de Mello, W. J. M.; de Mello Neto, J. R. T.; de Mitri, I.; de Souza, V.; de Vries, K. D.; Decerprit, G.; Del Peral, L.; Deligny, O.; Dembinski, H.; Denkiewicz, A.; di Giulio, C.; Diaz, J. C.; Díaz Castro, M. L.; Diep, P. N.; Dobrigkeit, C.; D'Olivo, J. C.; Dong, P. N.; Dorofeev, A.; Dos Anjos, J. C.; Dova, M. T.; D'Urso, D.; Dutan, I.; Ebr, J.; Engel, R.; Erdmann, M.; Escobar, C. O.; Etchegoyen, A.; Facal San Luis, P.; Falcke, H.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Ferguson, A. P.; Ferrero, A.; Fick, B.; Filevich, A.; Filipčič, A.; Fliescher, S.; Fracchiolla, C. E.; Fraenkel, E. D.; Fröhlich, U.; Fuchs, B.; Gamarra, R. F.; Gambetta, S.; García, B.; García Gámez, D.; Garcia-Pinto, D.; Gascon, A.; Gemmeke, H.; Gesterling, K.; Ghia, P. L.; Giaccari, U.; Giller, M.; Glass, H.; Gold, M. S.; Golup, G.; Gomez Albarracin, F.; Gómez Berisso, M.; Gonçalves, P.; Gonzalez, D.; Gonzalez, J. G.; Gookin, B.; Góra, D.; Gorgi, A.; Gouffon, P.; Gozzini, S. R.; Grashorn, E.; Grebe, S.; Griffith, N.; Grigat, M.; Grillo, A. F.; Guardincerri, Y.; Guarino, F.; Guedes, G. P.; Hague, J. D.; Hansen, P.; Harari, D.; Harmsma, S.; Harton, J. L.; Haungs, A.; Hebbeker, T.; Heck, D.; Herve, A. E.; Hojvat, C.; Holmes, V. C.; Homola, P.; Hörandel, J. R.; Horneffer, A.; Hrabovský, M.; Huege, T.; Insolia, A.; Ionita, F.; Italiano, A.; Jiraskova, S.; Kadija, K.; Kampert, K. H.; Karhan, P.; Karova, T.; Kasper, P.; Kégl, B.; Keilhauer, B.; Keivani, A.; Kelley, J. L.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Knapp, J.; Koang, D.-H.; Kotera, K.; Krohm, N.; Krömer, O.; Kruppke-Hansen, D.; Kuehn, F.; Kuempel, D.; Kulbartz, J. K.; Kunka, N.; La Rosa, G.; Lachaud, C.; Lautridou, P.; Leão, M. S. A. B.; Lebrun, D.; Lebrun, P.; Leigui de Oliveira, M. A.; Lemiere, A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; López, R.; Lopez Agüera, A.; Louedec, K.; Lozano Bahilo, J.; Lucero, A.; Ludwig, M.; Lyberis, H.; Macolino, C.; Maldera, S.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Marin, V.; Maris, I. C.; Marquez Falcon, H. R.; Marsella, G.; Martello, D.; Martin, L.; Martínez Bravo, O.; Mathes, H. J.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.; Maurizio, D.; Mazur, P. O.; Medina-Tanco, G.; Melissas, M.; Melo, D.; Menichetti, E.; Menshikov, A.; Mertsch, P.; Meurer, C.; Mićanović, S.; Micheletti, M. I.; Miller, W.; Miramonti, L.; Mollerach, S.; Monasor, M.; Monnier Ragaigne, D.; Montanet, F.; Morales, B.; Morello, C.; Moreno, E.; Moreno, J. C.; Morris, C.; Mostafá, M.; Moura, C. A.; Mueller, S.; Muller, M. A.; Müller, G.; Münchmeyer, M.; Mussa, R.; Navarra, G.; Navarro, J. L.; Navas, S.; Necesal, P.; Nellen, L.; Nelles, A.; Nhung, P. T.; Nierstenhoefer, N.; Nitz, D.; Nosek, D.; Nožka, L.; Nyklicek, M.; Oehlschläger, J.; Olinto, A.; Oliva, P.; Olmos-Gilbaja, V. M.; Ortiz, M.; Pacheco, N.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Palmieri, N.; Parente, G.; Parizot, E.; Parra, A.; Parrisius, J.; Parsons, R. D.; Pastor, S.; Paul, T.; Pech, M.; PeĶala, J.; Pelayo, R.; Pepe, I. M.; Perrone, L.; Pesce, R.; Petermann, E.; Petrera, S.; Petrinca, P.; Petrolini, A.; Petrov, Y.; Petrovic, J.; Pfendner, C.; Phan, N.; Piegaia, R.; Pierog, T.; Pieroni, P.; Pimenta, M.; Pirronello, V.; Platino, M.; Ponce, V. H.; Pontz, M.; Privitera, P.; Prouza, M.; Quel, E. J.; Rautenberg, J.; Ravel, O.; Ravignani, D.; Revenu, B.; Ridky, J.; Risse, M.; Ristori, P.; Rivera, H.; Rivière, C.; Rizi, V.; Robledo, C.; Rodrigues de Carvalho, W.; Rodriguez, G.; Rodriguez Martino, J.; Rodriguez Rojo, J.; Rodriguez-Cabo, I.; Rodríguez-Frías, M. D.; Ros, G.; Rosado, J.; Rossler, T.; Roth, M.; Rouillé-D'Orfeuil, B.; Roulet, E.; Rovero, A. C.; Rühle, C.; Salamida, F.; Salazar, H.; Salina, G.; Sánchez, F.; Santander, M.; Santo, C. E.; Santos, E.; Santos, E. M.; Sarazin, F.; Sarkar, S.; Sato, R.; Scharf, N.; Scherini, V.; Schieler, H.; Schiffer, P.; Schmidt, A.; Schmidt, F.; Schmidt, T.; Scholten, O.; Schoorlemmer, H.; Schovancova, J.; Schovánek, P.; Schroeder, F.; Schulte, S.; Schuster, D.; Sciutto, S. J.; Scuderi, M.; Segreto, A.; Semikoz, D.; Settimo, M.; Shadkam, A.; Shellard, R. C.; Sidelnik, I.; Sigl, G.; Śmiałkowski, A.; Šmída, R.; Snow, G. R.; Sommers, P.; Sorokin, J.; Spinka, H.; Squartini, R.; Stapleton, J.; Stasielak, J.; Stephan, M.; Stutz, A.; Suarez, F.; Suomijärvi, T.; Supanitsky, A. D.; Šuša, T.; Sutherland, M. S.; Swain, J.; Szadkowski, Z.; Szuba, M.; Tamashiro, A.; Tapia, A.; Taşcău, O.; Tcaciuc, R.; Tegolo, D.; Thao, N. T.; Thomas, D.; Tiffenberg, J.; Timmermans, C.; Tiwari, D. K.; Tkaczyk, W.; Todero Peixoto, C. J.; Tomé, B.; Tonachini, A.; Travnicek, P.; Tridapalli, D. B.; Tristram, G.; Trovato, E.; Tueros, M.; Ulrich, R.; Unger, M.; Urban, M.; Valdés Galicia, J. F.; Valiño, I.; Valore, L.; van den Berg, A. M.; Vargas Cárdenas, B.; Vázquez, J. R.; Vázquez, R. A.; Veberič, D.; Verzi, V.; Videla, M.; Villaseñor, L.; Wahlberg, H.; Wahrlich, P.; Wainberg, O.; Warner, D.; Watson, A. A.; Weber, M.; Weidenhaupt, K.; Weindl, A.; Westerhoff, S.; Whelan, B. J.; Wieczorek, G.; Wiencke, L.; Wilczyńska, B.; Wilczyński, H.; Will, M.; Williams, C.; Winchen, T.; Winders, L.; Winnick, M. G.; Wommer, M.; Wundheiler, B.; Yamamoto, T.; Younk, P.; Yuan, G.; Zamorano, B.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zaw, I.; Zepeda, A.; Ziolkowski, M.

    2011-03-01

    We present the results of searches for dipolar-type anisotropies in different energy ranges above 2.5 × 1017 eV with the surface detector array of the Pierre Auger Observatory, reporting on both the phase and the amplitude measurements of the first harmonic modulation in the right-ascension distribution. Upper limits on the amplitudes are obtained, which provide the most stringent bounds at present, being below 2% at 99% C.L. for EeV energies. We also compare our results to those of previous experiments as well as with some theoretical expectations.

  2. The Einstein Observatory catalog of IPC x ray sources. Volume 5E: Right ascension range 12h 00m to 15h 59m

    NASA Technical Reports Server (NTRS)

    Harris, D. E.; Forman, W.; Gioia, I. M.; Hale, J. A.; Harnden, F. R., Jr.; Jones, C.; Karakashian, T.; Maccacaro, T.; Mcsweeney, J. D.; Primini, F. A.

    1993-01-01

    The Einstein Observatory (HEAO-2, launched November 13, 1978) achieved radically improved sensitivity over previous x-ray missions through the use of focusing optics, which simultaneously afforded greatly reduced background and produced true images. During its 2.5-yr mission, the Einstein X-Ray Telescope was pointed toward some 5,000 celestial targets, most of which were detected, and discovered several thousand additional 'serendipitous' sources in the observed fields. This catalog contains contour diagrams and source data, obtained with the imaging proportional counter in the 0.16 to 3.5 keV energy band, and describes methods for recovering upper limits for any sky position within the observed images. The main catalog consists of six volumes (numbered 2 through 7) of right ascension ordered pages, each containing data for one observation. Along with the primary documentation describing how the catalog was constructed, volume 1 contains a complete source list, results for merged fields, a reference system to published papers, and data useful for calculating upper limits and fluxes.

  3. The Einstein Observatory catalog of IPC x ray sources. Volume 4E: Right ascension range 08h 00m to 11h 59m

    NASA Technical Reports Server (NTRS)

    Harris, D. E.; Forman, W.; Gioia, I. M.; Hale, J. A.; Harnden, F. R., Jr.; Jones, C.; Karakashian, T.; Maccacaro, T.; Mcsweeney, J. D.; Primini, F. A.

    1993-01-01

    The Einstein Observatory (HEAO-2, launched November 13, 1978) achieved radically improved sensitivity over previous x-ray missions through the use of focusing optics which simultaneously afforded greatly reduced background and produced true images. During its 2.5-yr mission, the Einstein X-Ray Telescope was pointed toward some 5,000 celestial targets, most of which were detected, and discovered several thousand additional 'serendipitous' sources in the observed fields. This catalog contains contour diagrams and source data, obtained with the imaging proportional counter in the 0.16 to 3.5 keV energy band, and describes methods for recovering upper limits for any sky position within the observed images, The main catalog consists of six volumes (numbered 2 through 7) of right ascension ordered pages, each containing data for one observation. Along with the primary documentaion describing how the catalog was constructed, volume 1 contains a complete source list, results for merged fields, a reference system to published papers, and data useful for calculating upper limits and fluxes.

  4. The Einstein Observatory catalog of IPC x ray sources. Volume 6E: Right ascension range 16h 00m to 19h 59m

    NASA Technical Reports Server (NTRS)

    Harris, D. E.; Forman, W.; Gioia, I. M.; Hale, J. A.; Harnden, F. R., Jr.; Jones, C.; Karakashian, T.; Maccacaro, T.; Mcsweeney, J. D.; Primini, F. A.

    1993-01-01

    The Einstein Observatory (HEAO-2 launched November 13, 1978) achieved radically improved sensitivity over previous x-ray missions through the use of focusing optics, which simultaneously afforded greatly reduced background and produced true images. During its 2.5-yr mission, the Einstein X-Ray Telescope was pointed toward some 5,000 celestial targets, most of which were detected, and discovered several thousand additional 'serendipitous' sources in the observed fields. This catalog contains contour diagrams and source data, obtained with the imaging proportional counter in the 0.16 to 3.5 keV energy band, and describes methods for recovering upper limits for any sky position within the observed images. The main catalog consists of six volumes (numbered 2 through 7) of right ascension ordered pages, each containing data for one observation. Along with the primary documentation describing how the catalog was constructed, volume 1 contains a complete source list, results for merged fields, a reference system to published papers, and data useful for calculating upper limits and fluxes.

  5. The Einstein Observatory catalog of IPC x ray sources. Volume 3E: Right ascension range 04h 00m to 07h 59m

    NASA Technical Reports Server (NTRS)

    Harris, D. E.; Forman, W.; Gioia, I. M.; Hale, J. A.; Harnden, F. R., Jr.; Jones, C.; Karakashian, T.; Maccacaro, T.; Mcsweeney, J. D.; Primini, F. A.

    1993-01-01

    The Einstein Observatory (HEAO-2, launched November 13, 1978) achieved radically improved sensitivity over previous x-ray missions through the use of focusing optics which simultaneously afforded greatly reduced background and produced true images. During its 2.5-yr mission, the Einstein X-Ray Telescope was pointed toward some 5,000 celestial targets, most of which were detected, and discovered several thousand additional 'serendipitous' sources in the observed fields. This catalog contains contour diagrams and source data, obtained with the imaging proportional counter in the 0.16 to 3.5 keV energy band, and describes methods for recovering upper limits for any sky position within the observed images. The main catalog consists of six volumes (numbered 2 through 7) of right ascension ordered pages, each containing data for one observation. Along with the primary documentation describing how the catalog was constructed, volume 1 contains a complete source list, results for merged fields, a reference system to published papers and data useful for calculating upper limits and fluxes.

  6. The Einstein Observatory catalog of IPC x ray sources. Volume 7E: Right ascension range 20h 00m to 23h 59m

    NASA Technical Reports Server (NTRS)

    Harris, D. E.; Forman, W.; Gioia, I. M.; Hale, J. A.; Harnden, F. R., Jr.; Jones, C.; Karakashian, T.; Maccacaro, T.; Mcsweeney, J. D.; Primini, F. A.

    1993-01-01

    The Einstein Observatory (HEAO-2, launched November 13, 1978) achieved radically improved sensitivity over previous x-ray missions through the use of focusing optics which simultaneously afforded greatly reduced background and produced true images. During its 2.5-yr mission, the Einstein X-Ray Telescope was pointed toward some 5,000 celestial targets, most of which were detected, and discovered several thousand additional 'serendipitous' sources in the observed fields. This catalog contains contour diagrams and source data, obtained with the imaging proportional counter in the 0.16 to 3.5 keV energy band, and describes methods for recovering upper limits for any sky position within the observed images. The main catalog consists of six volumes (numbered 2 through 7) of right ascension ordered pages, each containing data for one observation. Along with the primary documentation describing how the catalog was constructed, volume 1 contains a complete source list, results for merged fields, a reference system to published papers, and data useful for calculating upper limits and fluxes.

  7. The Einstein Observatory catalog of IPC x ray sources. Volume 2E: Right ascension range 00h 00m to 03h 59m

    NASA Technical Reports Server (NTRS)

    Harris, D. E.; Forman, W.; Gioia, I. M.; Hale, J. A.; Harnden, F. R., Jr.; Jones, C.; Karakashian, T.; Maccacaro, T.; Mcsweeney, J. D.; Primini, F. A.

    1993-01-01

    The Einstein Observatory (HEAO-2, launched November 13, 1978) achieved radically improved sensitivity over previous x-ray missions through the use of focusing optics which simultaneously afforded greatly reduced background and produced true images. During its 2.5-yr mission, the Einstein X-Ray Telescope was pointed toward some 5,000 celestial targets, most of which were detected, and discovered several thousand additional 'serendipitous' sources in the observed fields. This catalog contains contour diagrams and source data, obtained with the imaging proportional counter in the 0.16 to 3.5 keV energy band, and describes methods for recovering upper limits for any sky position within the observed images. The main catalog consists of six volumes (numbered 2 through 7) of right ascension ordered pages, each containing data for one observation. Along with the primary documentation describing how the catalog was constructed, volume 1 contains a complete source list, results for merged fields, a reference system to published papers and data useful for calculating upper limits and fluxes.

  8. Resonance State in {sup 7}H

    SciTech Connect

    Caamano, M.; Mittig, W.; Savajols, H.; Demonchy, C. E.; Jurado, B.; Rejmund, F.; Rejmund, M.; Roussel-Chomaz, P.; Gillibert, A.; Obertelli, A.; Lemmon, R.; Wolski, R.

    2007-08-10

    The existence of the {sup 7}H nuclear system was investigated via a one-proton transfer reaction with a {sup 8}He beam at 15.4A MeV and a {sup 12}C gas target. The experimental setup was based on the active-target MAYA which allowed a complete reconstruction of the reaction kinematics. The existence of the {sup 7}H was confirmed with the identification of seven events where the system was formed with a resonance energy of 0.57{sub -0.21}{sup +0.42} MeV above the {sup 3}H+4n threshold and a resonance width of 0.09{sub -0.06}{sup +0.94} MeV. This study represents an unambiguous proof of the existence of the most neutron-proton unbalanced system presently found.

  9. [Expression and Subcellular Distribution of Costimulatory Molecules B7-H1,B7-H3 and B7-H4 in Human Hematologic Malignancy Cell Lines].

    PubMed

    Zhang, Wei; Wang, Jing; Wang, Yan-Fang; Zhu, Ming-Xia; Wan, Wen-Li; Li, Hai-Shen; Wu, Fei-Fei; Yan, Xin-Xing; Ke, Xiao-Yan

    2016-10-01

    To investigate the expression and subcellular distribution of costimulatory molecules B7-H1, B7-H3 and B7-H4 in human hematologic malignancy cell lines. The expression and subcellular distribution of B7-H1, B7-H3 and B7-H4 in 13 human hematologic malignancy cell lines were determined by RT-PCR, qPCR, Western blot and flow cytometry, the peripheral blood mononuclear cells (PB MNC) of 12 volunteers were used as control. The mRNA of B7-H1, B7-H3 and B7-H4 was widely expressed in PB MNC and hematologic malignancy cell lines, with a lower level of B7-H4. The mRNA expression of 3 molecules was highest in Maver, Z138, and HL-60, respectively, while among them the B7-H3 and B7-H4 had no expression in CZ1. The nuclear and cytoplasmic protein of 3 costimulatory molecules abnormally overexpressed only in hematologic malignancy cell lines, with the highest level in U937, Z138, and Raji, respectively, while the B7-H3 and B7-H4 had no expression in CZ1. There were differences among mRNA expression, nuclear and cytoplasmic protein expression of 3 molecules in cell lines derived from the same type of tumor, but the differences of expression in mRNA and protein levels were not exactly the same. The B7-H3 expression abundance in membrane localization was higher in U937, Maver and Z138, while the membrane protein of B7-H1 and B7-H4 had no or low expression in 13 cell lines. The mRNA expression of costimulatory molecules B7-H1, B7-H3 and B7-H4 can be widely detected. The protein level of 3 costimulatory molecules abnormally overexpressed only in hematologic malignancy cell lines, moreover the subcellular localizations mostly was found in nucleus and cytoplasm, while the membrane protein expresses in low level or had no expression. There are differences among the expression of 3 molecules in cell lines derived from the same type of tumor.

  10. B7-H4 is Predictive of Poor Prognosis in Patients with Gastric Cancer

    PubMed Central

    Cui, YongHui; Li, ZhiHan

    2016-01-01

    Background Recently, some studies were performed to evaluate the relevance of B7-H4 and gastric cancer (GC) prognosis. However, the results remained controversial. Therefore, we performed the present meta-analysis. Material/Methods We performed a systematic search in PubMed and Web of Science databases. All data were extracted and reviewed from each eligible study independently by 2 investigators. The strength of association between B7-H4 and GC prognosis was assessed by computing odds ratio (OR) with its corresponding 95% confidence interval (CI). Results Six studies that evaluated the association between B7-H4 and GC prognosis were included. The results showed a statistically significant association of B7-H4 and GC prognosis (OR=1.63, 95%CI=1.30–2.03). Furthermore, we conducted subgroup analysis based on source of B7-H4; the results from blood (OR=1.71; 95%CI, 1.09–2.68) and tissue (OR=1.60; 95%CI, 1.03–2.07) indicated B7-H4 was significantly associated with poor prognosis. Conclusions This meta-analysis suggests that GC patients with high B7-H4 have poor prognosis. PMID:27820598

  11. The expression of B7-H3 and B7-H4 in human gallbladder carcinoma and their clinical implications.

    PubMed

    Liu, C-L; Zang, X-X; Huang, H; Zhang, H; Wang, C; Kong, Y-L; Zhang, H-Y

    2016-11-01

    To investigate the expression of B7-H3 and B7-H4 and their clinical implications in human gallbladder carcinoma. The expression of B7-H3 and B7-H4 in the 252 samples (126 cases of chronic cholecystitis and 126 cases of gallbladder cancer) was detected by the streptavidin-peroxidase immunohistochemical method, and their associations with tumor classification, clinical grade, and recurrence were assessed. In chronic cholecystitis tissue, B7-H3 and B7-H4 were not detected. In 126 cases of gallbladder carcinoma, the positive rates of B7-H3 and B7-H4 expression were 66.67% and 69.05% respectively (p < 0.05). The positive rate of B7-H3 in the primary-onset group was 53.57%, and that in recurrence group was 92.86% (p < 0.05). The positive rate of B7-H4 in the primary-onset group was 85.19%, and that in recurrence group was 40.00% (p < 0.05). Expression of B7-H3 was consistent with B7-H4 expression in gallbladder carcinoma. B7-H3 and B7-H4 were up-regulated in gallbladder cancer; the high expression of B7-H3 may contribute to the early diagnosis of gallbladder carcinoma and the assessment of postoperative survival and recurrence. B7-H4 may play an important role in the incidence of gallbladder cancer. B7-H3 and B7-H4 may play a synergetic role in gallbladder carcinoma. Combined tests were available for the diagnosis, degree assessment and prognosis of gallbladder carcinoma, which may be a new target for molecular targeted therapy of gallbladder carcinoma.

  12. Production and Characterization of the 7H Resonance

    SciTech Connect

    Caamano, M.; Cortina, D.; Demonchy, C. E.; Jurado, B.; Mittig, W.; Rejmund, F.; Rejmund, M.; Roussel-Chomaz, P.; Savajols, H.; Chartier, M.; Fernandez, B.; Gomez Hornillos, M. B.; Gillibert, A.; Obertelli, A.; Lemmon, R.; Wolski, R.

    2007-05-22

    The 7H resonance was produced via one-proton transfer reaction between a 8He beam at 15.4A MeV and a 12C gas target. The experimental setup was based on the active-target MAYA which allowed a complete reconstruction of the reaction kinematics. The characterization of the identified 7H events resulted in a resonance energy of 600 keV above the 3H+4n threshold and a resonance width of 100 keV. This study represents the first unambiguous proof of the existence of the 7H state.

  13. [Preparation of anti-B7-H4 monoclonal antibody to investigate B7-H4 expression in pancreatic cancer].

    PubMed

    Hong, Bo; Qian, Yun; Yao, Hang-Ping

    2013-09-01

    To prepare a monoclonal antibody (mAb) against extracellular domain of B7-H4 and to investigate the expression of B7-H4 in pancreatic cancer tissue with the prepared mAb. Balb/c mice were immunized with 3T3-B7-H4 cells and the splenic cells of the immunized mice were fused with Sp2/0 myeloma cells by conventional hybridoma techniques. An indirect ELISA method using 3T3-B7-H4 lysate as antigen was established to screen antibody-producing hybridoma cell lines. Western blott, immunoprecipitation (IP), and immunohistochemistry (IHC) were applied to characterize the mAb. Immunohistochemical staining was used to detect the expression of B7-H4 in human pancreatic cancer tissue. The correlation of B3-H4 expressions and pathological features of pancreatic cancer was analyzed. A hybridoma cell line secreting mAb against B7-H4 was obtained. The subclass of this mAb was IgM, and the light chain was Kappa. Western blot and IP showed that the mAb specifically recognized B7-H4. IHC staining revealed that the mAb stained in a predominantly diffuse plasmalemmal or cytoplasmic pattern when applied to certain tumor tissues. The B7-H4 was diffusely expressed in the cytoplasma and/or membrane of pancreatic cancer tissue, which was much higher than that expressed in normal pancreatic tissue (4.00 ± 1.44 compared with 1.12 ± 0.78, P ± 0.01). The expression of B7-H4 was higher in pancreatic cancer tissues with higher pathological grade or with lymph node metastasis as compared with that in pancreatic cancer tissues with lower grade or with no lymph mode metastasis (6.10 ± 0.72 compared with 3.55 ± 1.12,P<0.01: 6.14 ± 0.66 compared with 3.70 ± 1.25,P<0.01). The expression level of B7-H4 was not related to patients'age and gender. Monoclonal antibody against B7-H4 with high activity and specificity has been prepared successfully. The expression of B7-H4 in pancreatic cancer tissue is up-regulated,which is closely related to the tumor grade and lymph node metastasis in pancreatic

  14. Electronic Absorption Spectroscopy and Franck-Condon Simulations for HC7H and MeC7H

    NASA Astrophysics Data System (ADS)

    Haenni, Benjamin C.; Shaffer, Christopher J.; Stanton, John F.; McMahon, Robert J.

    2014-06-01

    Highly unsaturated carbon chains of the HCnH family are important to the studies of combustion chemistry and the interstellar medium (ISM). Several members of this family (n=2,4,6) have been detected in the ISM by infrared spectroscopy. We have successfully matrix-isolated HC7H and MeC7H species and studied them using electronic absorption, FTIR, and EPR spectroscopy. The ground state potential energy surface was explored using ab initio (CCSD(T)/cc-pVTZ (fc)) methods to discover triplet minima for both species. Equation of motion coupled cluster calculations (EOM-CCSD/ANO1) of low-lying excited states allowed for Franck-Condon simulations. The comparison of the simulated spectra to the vibronic progression observed experimentally in the UV/Vis spectra permits assignment of a linear ground state triplet structure for both HC7H and MeC7H.

  15. Prognostic investigations of B7-H1 and B7-H4 expression levels as independent predictor markers of renal cell carcinoma.

    PubMed

    Safaei, Hamid Reza; Rostamzadeh, Ayoob; Rahmani, Omid; Mohammadi, Mohsen; Ghaderi, Omar; Yahaghi, Hamid; Ahmadi, Koroosh

    2016-06-01

    In order to evaluate the correlation of B7-H4 and B7-H1 with renal cell carcinoma (RCC), we analyzed B7-H1 and B7-H4 expressions and their clinical significance by immunohistochemical method. Our result indicated that B7-H4-positive staining was detected in 58.13 % of RCC tissues (25 tissues tumors), and there were 18 tissues of patients without detectable B7-H4. Furthermore, 21 cases (48.83 %) were B7-H1-positive. Positive tumor expressions of B7-H4 and B7-H1 were markedly related to advanced TNM stage (P = 0.001; P = 0.014), high grade (P = 0.001; P = 002), and larger tumor size (P = 0.002; P = 024) in RCC tissues than patients with B7-H4-negative and B7-H1-negative in RCC tissues. The patients with B7-H1 and B7-H4-positive expressions were found to be markedly correlated with the overall survival of the patients (P < 0.05) and tended to have an increased risk of death when compared with negative expression groups. Univariate analysis showed that B7-H4 and B7-H1 expressions, TNM stage, high grade, and tumor size were significantly related to the prognosis of RCC. Furthermore, multivariate analysis showed that B7-H4 and B7-H1 expressions decreased overall survival. The adjusted HR for B7-H1 was 2.83 (95 % CI 1.210-2.971; P = 0.031) and also was 2.918 (95 % CI 1.243-3.102; P = 0.006) for B7-H4 that showed these markers were independent prognostic factors in RCC patients. The expressions of B7-H1 and B7-H4 in RCC patients indicate that these markers may be as a predictor of tumor development and death risk. Further investigations can be helpful to confirm B7-H1 and B7-H4 roles as an independent predictor of clinical RCC outcome.

  16. Characterization of a Soluble B7-H3 (sB7-H3) Spliced from the Intron and Analysis of sB7-H3 in the Sera of Patients with Hepatocellular Carcinoma

    PubMed Central

    Chen, Weiwei; Liu, Peixin; Wang, Yedong; Nie, Weimin; Li, Zhiwei; Xu, Wen; Li, Fengyi; Zhou, Zhiping; Zhao, Min; Liu, Henggui

    2013-01-01

    B7-H3 is a recently discovered member of the B7 superfamily molecules and has been found to play a negative role in T cell responses. In this study, we identified a new B7-H3 isoform that is produced by alternative splicing from the forth intron of B7-H3 and encodes the sB7-H3 protein. Protein sequence analysis showed that sB7-H3 contains an additional four amino acids, encoded by the intron sequence, at the C-terminus compared to the ectodomain of 2Ig-B7-H3. We further found that this spliced sB7-H3 plays a negative regulatory role in T cell responses and serum sB7-H3 is higher in patients with hepatocellular carcinoma (HCC) than in healthy donors. Furthermore, we found that the expression of the spliced sb7-h3 gene is higher in carcinoma and peritumor tissues than in PBMCs of both healthy controls and patients, indicating that the high level of serum sB7-H3 in patients with HCC is caused by the increased expression of this newly discovered spliced sB7-H3 isoform in carcinoma and peritumor tissues. PMID:24194851

  17. [Correlation of Plasma Co-stimulatory Molecules B7-H2 and B7-H3 with Platelet Auto-antibodies in Patients with Immune Thrombocytopenic Purpura].

    PubMed

    Zuo, Bin; Zhao, Yun-Xiao; Yang, Jian-Feng; He, Yang

    2015-08-01

    To investigate whether the plasma level of platelet auto- antibodies in ITP patients is related to that of co-stimulatory molecules sB7-H2 and sB7-H3. A total of 61 ITP patients and 25 healthy controls from the First Affiliated Hospital of Soochow University from June 2012 to August 2013 were enrolled in this study. The expression levels of platelet auto-antibodies against 5 glycoproteins (GPIX, GP Ib, GP IIIa, GPIIb and P-selectin) in plasma were detected by flow cytometric immuno-beads array, and the expression of soluable co-stimulatory molecules sB7-H2 and sB7-H3 was measured by ELISA. The plasma levels of 5 auto-antibodies against platelet membrance glycoproteins significantly increased in ITP patiens (P < 0.01). Compared with healthy controls, sB7-H2 levels increased (P < 0.05), while the sB7-H3 level did not significantly change (r = 0.13, P > 0.05). However, the correlation analysis showed that sB7-H3 negatively correlated with platelet P-selectin auto-antibody (r = -0.46, P < 0.05), and sB7-H2 and sB7-H3 significantly reduced in ITP patients with positive P-selectin auto-antibody (P < 0.01). In ITP patients, platelet counts negatively correlated with sB7-H2 (r = -0.3907, P < 0.01), but did not correlate with sB7-H3. Soluble costimulatory molecule sB7-H2 elevates in ITP patients, and the level of sB7-H3 is associated with auto-antibodies against P-selectin, suggesting that costimulatory molecules B7-H2 and B7-H3 may be involved in the pathogenesis of immune regulation abnormality in ITP.

  18. Interval Training

    MedlinePlus

    ... before trying any type of interval training. Recent studies suggest, however, that interval training can be used safely for short periods even in individuals with heart disease. Also keep the risk of overuse injury in mind. If you rush into a strenuous workout before ...

  19. B7-H3 is a potent inhibitor of human T cell activation: No evidence for B7-H3 and TREML2 interaction

    PubMed Central

    Leitner, Judith; Klauser, Christoph; Pickl, Winfried F.; Stöckl, Johannes; Majdic, Otto; Bardet, Anaïs F.; Kreil, David P.; Dong, Chen; Yamazaki, Tomohide; Zlabinger, Gerhard; Pfistershammer, Katharina; Steinberger, Peter

    2010-01-01

    B7-H3 belongs to the B7 superfamily, a group of molecules that costimulate or down-modulate T cell responses. Although it was shown that B7-H3 can inhibit T cell responses, several studies - most of them performed in murine systems - found B7-H3 to act in a costimulatory manner. In this study we have specifically addressed a potential functional dualism of human B7-H3 by assessing the effect of this molecule under varying experimental conditions as well as on different T cell subsets. We show that B7-H3 does not costimulate human T cells. In presence of strong activating signals, B7-H3 potently and consistently down-modulated human T cell responses. This inhibitory effect was evident when analyzing proliferation and cytokine production and affected naïve as well as pre-activated T cells. We furthermore demonstrate that B7-H3 - T cell interaction is characterized by an early suppression of IL-2 and that T cell inhibition can be reverted by exogenous IL-2. Since TREML2 has been recently described as costimulatory receptor of murine B7-H3 we have extensively analysed interaction of human B7-H3 with TREML2 (TLT2). In these experiments we found no evidence for such an interaction. Furthermore our data do not point to a role for murine TREML2 as a receptor for murine B7-H3. PMID:19544488

  20. Tumor Regression and Delayed Onset Toxicity Following B7-H4 CAR T Cell Therapy.

    PubMed

    Smith, Jenessa B; Lanitis, Evripidis; Dangaj, Denarda; Buza, Elizabeth; Poussin, Mathilde; Stashwick, Caitlin; Scholler, Nathalie; Powell, Daniel J

    2016-11-01

    B7-H4 protein is frequently overexpressed in ovarian cancer. Here, we engineered T cells with novel B7-H4-specific chimeric antigen receptors (CARs) that recognized both human and murine B7-H4 to test the hypothesis that B7-H4 CAR T cell therapy can be applied safely in preclinical models. B7-H4 CAR T cells specifically secreted IFN-γ and lysed B7-H4(+) targets. In vivo, B7-H4 CAR T cells displayed antitumor reactivity against B7-H4(+) human ovarian tumor xenografts. Unexpectedly, B7-H4 CAR T cell treatment reproducibly showed delayed, lethal toxicity 6-8 weeks after therapy. Comprehensive assessment of murine B7-H4 protein distribution uncovered expression in ductal and mucosal epithelial cells in normal tissues. Postmortem analysis revealed the presence of widespread histologic lesions that correlated with B7-H4(+) expression, and were inconsistent with graft versus host disease. Lastly, expression patterns of B7-H4 protein in normal human tissue were comparable to distribution in mice, advancing our understanding of B7-H4. We conclude that B7-H4 CAR therapy mediates control of cancer outgrowth. However, long-term engraftment of B7-H4 CAR T cells mediates lethal, off-tumor toxicity that is likely due to wide expression of B7-H4 in healthy mouse organs. This model system provides a unique opportunity for preclinical evaluation of safety approaches that limit CAR-mediated toxicity after tumor destruction in vivo.

  1. Assessment of combined expression of B7-H3 and B7-H4 as prognostic marker in esophageal cancer patients

    PubMed Central

    Shi, Liangrong; Wu, Changping; Jiang, Jingting

    2016-01-01

    The co-stimulatory ligands of B7-family have been confirmed to play an important role in negatively regulating the T-cell mediated anti-tumor immunity. In addition, these inhibitory molecules are also aberrantly expressed on various human cancers tissues, and significantly associated with cancer progression and patients' poor prognoses. We have previously reported that B7-H3 and B7-H4 ligands are highly expressed in human esophageal cancer tissues. Herein, we tried to further analyze the value of their combined expression on prognostic prediction for esophageal cancer patients. We found that the combined expression of both B7-H3 and B7-H4 could be used as a valuable risk factor for predicting the prognosis of esophageal cancer patients (P=0.003). Moreover the status of these patients with high expression of both B7-H3 and B7-H4, was positively and significantly associated with the tumor invasion depth (P=0.0414) and TNM stage (P=0.0414). The Cox multivariate proportional hazards regression analysis revealed that the tumor size (P=0.007), the TNM stage (P=0.024) and the status of both B7-H3 and B7-H4 high expression (P=0.011), could be used as an independent risk factor for predicting patients' postoperative prognosis, respectively. In conclusion, our data indicated that the combined application of B7-H3 and B7-H4 expression can be effectively used as a prognostic marker in esophageal cancer patients. PMID:27764786

  2. B7-H1-dependent sex-related differences in tumor immunity and immunotherapy responses.

    PubMed

    Lin, Pei-Yi; Sun, Lishi; Thibodeaux, Suzanne R; Ludwig, Sara M; Vadlamudi, Ratna K; Hurez, Vincent J; Bahar, Rumana; Kious, Mark J; Livi, Carolina B; Wall, Shawna R; Chen, Lieping; Zhang, Bin; Shin, Tahiro; Curiel, Tyler J

    2010-09-01

    CD4(+)CD25(+)Foxp3(+) regulatory T cells (Tregs) are immunopathogenic in cancers by impeding tumor-specific immunity. B7-homologue 1 (B7-H1) (CD274) is a cosignaling molecule with pleiotropic effects, including hindering antitumor immunity. In this study, we demonstrate sex-dependent, B7-H1-dependent differences in tumor immunity and response to immunotherapy in a hormone-independent cancer, murine B16 melanoma. Antitumor immunity was better in B7-H1(-/-) females versus males as a result of reduced regulatory T cell function in the B7-H1(-/-) females, and clinical response following B7-H1 blockade as tumor immunotherapy was significantly better in wild-type females than in males, owing to greater B7-H1 blockade-mediated reduction of Treg function in females. Wild-type female Tregs expressed significantly lower B7-H1 versus males but were insensitive to estrogen in vitro. Female B7-H1(-/-) Tregs were exquisitely sensitive to estrogen-mediated functional reduction in vitro, suggesting that B7-H1 effects occur before terminal Treg differentiation. Immune differences were independent of known B7-H1 ligands. Sex-dependent immune differences are seldom considered in designing immune therapy or interpreting immunotherapy treatment results. Our data demonstrate that sex is an important variable in tumor immunopathogenesis and immunotherapy responses through differential Treg function and B7-H1 signaling.

  3. Expression of the Novel Costimulatory Molecule B7-H5 in Pancreatic Cancer.

    PubMed

    Byers, Joshua T; Paniccia, Alessandro; Kaplan, Jeffrey; Koenig, Michelle; Kahn, Nate; Wilson, Lora; Chen, Lieping; Schulick, Richard D; Edil, Barish H; Zhu, Yuwen

    2015-12-01

    This study investigated how the B7-H5 protein, a new member of the B7 family, is expressed in normal human pancreas tissues and examined its expression changes in pancreatic cancer. In this analysis, B7-H5 expression was examined by immunohistochemical staining of frozen specimens from patients undergoing pancreatic resection. Membranous B7-H5 protein was expressed on normal ductal epithelium within the pancreas. Other cell types from the normal pancreas, such as acinar cells and islet cells, did not express B7-H5. In adenocarcinoma, B7-H5 staining was decreased or absent. Interestingly, B7-H5 expression in intraductal papillary mucinous neoplasms varied with grade. No B7-H5 expression was found with other cancer types such as neuroendocrine tumors, but normal ducts adjacent to tumors were highly positive. The findings showed that B7-H5 expression was restricted to ductal cells in the normal pancreas and the expression was downregulated in pancreatic adenocarcinomas. In addition, the findings showed that B7-H5 expression changes within different stages of dysplasia. The study suggests that loss of the B7-H5 signal may contribute to immune evasion of pancreatic adenocarcinoma. However future studies are needed.

  4. EPR of Mn2+ -doped NiSO4 . 7H2O and MgSO4 . 7H2O: Mn2+ -Ni2+ exchange constant

    NASA Astrophysics Data System (ADS)

    Misra, Sushil K.; Kahrizi, Mojtaba

    1984-11-01

    X-band EPR measurements on Mn2+ -doped isostructural single crystals of paramagnetic NiSO4 . 7H2O and diamagnetic MgSO4 . 7H2O have been made at room, liquid-nitrogen, and liquid-helium temperatures. The spin-Hamiltonian parameters are evaluated from the data using a rigorous least-squares-fitting program suitable for electron-nuclear spin-coupled systems. Using the g shift in the paramagnetic lattice from that in the diamagnetic lattice a value of 4.293 GHz for the Mn2+-Ni2+ exchange constant in NiSO4 . 7H2O is estimated. For NiSO4 . 7H2O host the linewidths exhibit temperature and magnetic field dependence. The temperature dependence of the zero-field splitting parameter b02 for both hosts is found to be linear, thus being explained as mainly due to the thermal expansion of the lattice.

  5. [Clinical significance of determination of serum B7-H4 in patients with malignant hematologic diseases].

    PubMed

    Wang, Xiao-Mei; Hu, Guo-Yan; Liu, Wei; Zheng, Shu-Hua; Lv, Jing; Wang, Hong-Mei; Xu, Jun-Fa

    2010-09-01

    To study the clinical significance of determination of serum B7-H4 in patients with malignant hematologic diseases. Serum B7-H4 levels were determined in 65 patients with leucemia, 34 patients with lymphoma, 12 patients with multiple myeloma as well as in 50 healthy controls. The serum B7-H4 levels in patients with lymphoma [(38.81+/-10.34) kappag/L] were significantly higher than healthy controls [(31.62+/-9.850) kappag/L] (P<0.01). But there are no significant difference of B7-H4 levels in serum among patients with leucemia, patients with multiple myeloma and healthy controls. These results suggest that the B7-H4 may correlated with lymphoma, but uncorrelated with leucemia and multiple myeloma. Measurement of serum B7-H4 level provide useful information for distinctive diagnosis of different kinds of malignant hematologic diseases.

  6. B7-H4 as a Target for Breast Cancer Immunotherapy

    DTIC Science & Technology

    2012-06-01

    intracellular B7- H4 has been shown to have anti-apoptotic effects in biliary epithelial cells from patients with primary biliary cirrhosis [9]. In biliary...epithelial cells acquired from primary biliary cirrhosis , Chen et al. [9] showed that silencing of B7-H4 using RNA interference was able to induce...Intracellular B7-H4 suppresses bile duct epithelial cell apoptosis in human biliary cirrhosis . Inflammation 34, 688-697 (2011). 11

  7. B7-H4 as a Target for Breast Cancer Immunotherapy

    DTIC Science & Technology

    2013-06-01

    AD_________________ Award Number: W81XWH-11-1-0466 TITLE: B7-H4 as a Target for Breast Cancer ...COVERED 1 June 2011 - 31 May 2013 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER B7-H4 as a Target for Breast Cancer Immunotherapy 5b. GRANT NUMBER...immune escape generated in breast cancer . Here we report the generation of 84 mouse monoclonal antibodies for the detection of B7-H4 by ELISA, 25 for

  8. B7-H6 protein expression has no prognostic significance in human gastric carcinoma.

    PubMed

    Chen, Xiao-Juan; Shen, Jin; Zhang, Guang-Bo; Chen, Wei-Chang

    2014-01-01

    B7-H6, a novel member of the B7 family which binds to NKp30 to trigger antitumor NK cell cytotoxicity and cytokine secretion. Recently, B7-H family has been reported to be a negative regulator of the immune response in patients with gastric carcinoma. However, no reports have investigated the clinical significance of B7-H6 expression in human gastric cancer. We present the first study to the clinicopathological and prognostic value of B7-H6 in primary gastric tumors and adjacent non-tumor tissues at the protein level. Here we show that B7-H6 immunoreactivity was expressed in 6/60 (10%) gastric tumors and 8/43 (18.60%) adjacent non-tumor tissues. No statistical difference was found between B7-H6 expression and various prognostic factors; however, B7-H6-positive carcinomas were significantly associated with a higher differentiation (p = 0.047). The survival analysis did not confirm the prognostic significance of B7-H6 expression in gastric cancer patients. Our data suggest that B7-H6, as detected by immunohistochemistry, is of limited value as a prognostic marker for gastric cancer.

  9. Prognostic significance of B7-H4 expression in matched primary pancreatic cancer and liver metastases

    PubMed Central

    Qian, Yun; Sang, Yiwen; Wang, Frederick X.C.; Hong, Bo; Wang, Qi; Zhou, Xinhui; Weng, Tianhao; Wu, Zhigang; Zheng, Min; Zhang, Hong; Yao, Hangping

    2016-01-01

    Liver metastasis development in pancreatic cancer patients is common and confers a poor prognosis. Clinical relevance of biomarker analysis in metastatic tissue is necessary. B7-H4 has an inhibitory effect on T cell mediated response and may be involved in tumor development. Although B7-H4 expression has been detected in pancreatic cancer, its expression in liver metastases from pancreatic cancer is still unknown. In this study, overall 43 pancreatic cancer liver metastases (with matched primaries in 15/43 cases) and 57 pancreatic cancer cases without liver metastases or other distant metastases were analyzed for their expression of B7-H4 by immunohistochemistry. Survival curves and log-rank tests were used to test the association of B7-H4 expression with survival. B7-H4 was highly expressed in 28 (65.1%) of the 43 liver metastases and 9 (60.0%) of the 15 matched primary tumors. The expression of B7-H4 in liver metastases was significantly higher than in the matched primary tumors (p < 0.05). Patients with high B7-H4 expression in their primary pancreatic cancer had higher risk of developing liver metastases (p < 0.05). In univariate analysis, B7-H4 expression was significantly associated with the risk of death (p < 0.05). And the multivariate analysis identified that B7-H4 was an independent prognostic indicator (p < 0.05). Our results revealed B7-H4 to be associated with poor prognosis in patients with pancreatic cancer liver metastasis. B7-H4 may promote pancreatic cancer metastasis and was promising to be a potential prognostic indicator of pancreatic cancer. PMID:27750217

  10. B7-H3 silencing inhibits tumor progression of mantle cell lymphoma and enhances chemosensitivity.

    PubMed

    Zhang, Wei; Wang, Yanfang; Wang, Jing; Dong, Fei; Zhu, Mingxia; Wan, Wenli; Li, Haishen; Wu, Feifei; Yan, Xinxing; Ke, Xiaoyan

    2015-01-01

    B7-H3 (CD276), known as a member of B7 immunoregulatory family, is a type I transmembrane glycoprotein aberrantly expressed in numerous types of cancer and associated with poor prognosis. However, the role of B7-H3 in oncogenesis and chemosensitivity of mantle cell lymphoma (MCL) remains unknown. We determined the effects of downregulating B7-H3 expression on tumor progression and the sensitivity of chemotherapeutic drug in mantle cell lymphoma. B7-H3 knockdown was performed using lentivirus transduction in the Maver and Z138 mantle cell lymphoma cell lines, respectively. The effects of B7-H3 on cell proliferation, cycle, migration and invasion were investigated by CCK-8 assay, methyl cellulose colony forming assay, PI staining, and Transwell assays in vitro. By establishing Maver and Z138 xenograft models, the effects of B7-H3 on tumorigenicity were observed, and Ki-67 and PCNA was detected by immunohistochemistry. The downregulation of B7-H3 significantly decreased tumor proliferation in MCL in vitro and in vivo. In the B7-H3 knockdown groups of Maver and Z138 xenograft models, the mean inhibition rate of tumor growth was 59.1 and 65.0% (p=0.010 and 0.003), and the expression of both Ki-67 and PCNA were significantly lower, respectively. After B7-H3 silencing, the cell cycles of Maver and Z138 were both arrested at G0/G1 phase, and the cell migration rates and invasion capacity were decreased as well. Moreover, the impacts of B7-H3 RNAi on the antitumor effect of chemotherapy drugs were determined with CCK-8 and Annexin V-FITC/PI assays in vitro and with xenograft models in vivo. The silencing of B7-H3 increased the sensitivity of Maver and Z138 cells to rituximab and bendamustine and enhanced the drug-induced apoptosis, respectively. Our study demonstrates for the first time that B7-H3 promotes mantle cell lymphoma progression and B7-H3 knockdown significantly enhances the chemosensitivity. This may provide a new therapeutic approach to mantle cell lymphoma.

  11. Structure and Electronic Transitions of C7H4O2(+) and C7H5O2(+) Ions: Neon Matrix and Theoretical Studies.

    PubMed

    Fulara, Jan; Erattupuzha, Sonia; Garkusha, Iryna; Maier, John P

    2016-12-29

    C7H4O2(+) and C7H5O2(+) ions and the respective neutrals have been investigated by absorption spectroscopy in neon matrixes following mass selection of ions produced from salicylic acid. Three electronic transitions starting at 649.6, 431.0, and 372.0 nm are detected for C7H4O2(+) and assigned on the basis of CASPT2 energies and Franck-Condon simulations as the excitations from the X (2)A″ to the 1 (2)A″, 2 (2)A″, and 3 (2)A″ electronic states of 6-(oxomethylene)-2,4-cyclohexadien-1-one ion (A(+)). Absorptions commencing at 366.4 nm are observed for C7H5O2(+) and assigned to the 1 (2)A' ← X (2)A' electronic transition of (2-hydroxyphenyl)methanone ion (J(+)). Neutralization of J(+) leads to the appearance of four absorption systems attributed to the 4 (2)A″, 3 (2)A″, 2 (2)A″, and 1 (2)A″ ← X (2)A″ transitions of J with origin bands 291.3, 361.2, 393.8, and 461.2 nm.

  12. Tissue-expressed B7-H1 Critically Controls Intestinal Inflammation

    PubMed Central

    Scandiuzzi, Lisa; Ghosh, Kaya; Hofmeyer, Kimberly A.; Abadi, Yael M.; Lázár-Molnár, Eszter; Lin, Elaine Y.; Liu, Qiang; Jeon, Hyungjun; Almo, Steven C.; Chen, Lieping; Nathenson, Stanley G.; Zang, Xingxing

    2014-01-01

    SUMMARY B7-H1 (PD-L1) on immune cells plays an important role in T cell coinhibition by binding its receptor PD-1. Here we show that both human and mouse intestinal epithelium expressed B7-H1 and that B7-H1-deficient mice were highly susceptible to dextran sodium sulfate- or trinitrobenzenesulfonic acid-induced gut injury. B7-H1 deficiency during intestinal inflammation led to high mortality and morbidity, which were associated with severe pathological manifestations in the colon, including loss of epithelial integrity and overgrowth of commensal bacteria. Results from bone marrow chimeric and knock-out mice showed B7-H1 expressed on intestinal parenchyma, but not on hematopoietic cells, controlled intestinal inflammation in an adaptive immunity-independent fashion. Finally, we demonstrated that B7-H1 dampened intestinal inflammation by inhibiting TNF-α production and by stimulating IL-22 from CD11c+CD11b+ lamina propria cells. Thus, our data uncover a new mechanism by which intestinal tissue-expressed B7-H1 functions as an essential ligand for innate immune cells to prevent gut inflammation. PMID:24529703

  13. High resolution mapping of Dense spike-ar (dsp.ar) to the genetic centromere of barley chromosome 7H.

    PubMed

    Shahinnia, Fahimeh; Druka, Arnis; Franckowiak, Jerome; Morgante, Michele; Waugh, Robbie; Stein, Nils

    2012-02-01

    Spike density in barley is under the control of several major genes, as documented previously by genetic analysis of a number of morphological mutants. One such class of mutants affects the rachis internode length leading to dense or compact spikes and the underlying genes were designated dense spike (dsp). We previously delimited two introgressed genomic segments on chromosome 3H (21 SNP loci, 35.5 cM) and 7H (17 SNP loci, 20.34 cM) in BW265, a BC(7)F(3) nearly isogenic line (NIL) of cv. Bowman as potentially containing the dense spike mutant locus dsp.ar, by genotyping 1,536 single nucleotide polymorphism (SNP) markers in both BW265 and its recurrent parent. Here, the gene was allocated by high-resolution bi-parental mapping to a 0.37 cM interval between markers SC57808 (Hv_SPL14)-CAPSK06413 residing on the short and long arm at the genetic centromere of chromosome 7H, respectively. This region putatively contains more than 800 genes as deduced by comparison with the collinear regions of barley, rice, sorghum and Brachypodium, Classical map-based isolation of the gene dsp.ar thus will be complicated due to the infavorable relationship of genetic to physical distances at the target locus.

  14. Oral Squamous Carcinoma Cells Express B7-H1 and B7-DC Receptors in Vivo.

    PubMed

    Groeger, Sabine; Howaldt, H P; Raifer, H; Gattenloehner, S; Chakraborty, T; Meyle, J

    2017-01-01

    B7-H1 and B7-DC ligands are members of the B7 family with important regulatory functions in cell-mediated immune response. Both receptors are ligands of the programmed death receptor PD-1. B7-H1 expression has been detected in the majority of human carcinomas in vivo. B7-H1 mediated signals are able to negatively regulate activated T cell functions and survival, and enable tumor cells to overcome host response. The aim of this study was to investigate the expression of B7-H1 and B7-DC proteins in oral squamous cell carcinomas (OSCC) in vivo. Tissues from 15 samples were cryo-sected and following histological routine staining (HE), incubated with antibodies against human B7-H1 and B7-DC. Immuno-staining of pan-cytokeratin was performed to ascertain the epithelial origin of the tissue and CK 19 to demonstrate the proliferating stage. Confocal laser scanning microscopy confirmed the presence of both B7-H1 and B7-DC in all 15 OSCC. The B7-H1 and B7-DC staining was located in areas of the tissue that were identified as cancerous lesions in the previously stained HE sections before. Staining with Pan-CK and CK19 provided evidence for the epithelial origin and the proliferating stage of the tissue. The in vivo expression of the B7-H1 and B7-DC receptors in oral squamous cell carcinomas suggest that general mechanisms for immune evasion of tumors are also found in OSCC.

  15. Breast Cancer Detection by B7-H3-Targeted Ultrasound Molecular Imaging.

    PubMed

    Bachawal, Sunitha V; Jensen, Kristin C; Wilson, Katheryne E; Tian, Lu; Lutz, Amelie M; Willmann, Jürgen K

    2015-06-15

    Ultrasound complements mammography as an imaging modality for breast cancer detection, especially in patients with dense breast tissue, but its utility is limited by low diagnostic accuracy. One emerging molecular tool to address this limitation involves contrast-enhanced ultrasound using microbubbles targeted to molecular signatures on tumor neovasculature. In this study, we illustrate how tumor vascular expression of B7-H3 (CD276), a member of the B7 family of ligands for T-cell coregulatory receptors, can be incorporated into an ultrasound method that can distinguish normal, benign, precursor, and malignant breast pathologies for diagnostic purposes. Through an IHC analysis of 248 human breast specimens, we found that vascular expression of B7-H3 was selectively and significantly higher in breast cancer tissues. B7-H3 immunostaining on blood vessels distinguished benign/precursors from malignant lesions with high diagnostic accuracy in human specimens. In a transgenic mouse model of cancer, the B7-H3-targeted ultrasound imaging signal was increased significantly in breast cancer tissues and highly correlated with ex vivo expression levels of B7-H3 on quantitative immunofluorescence. Our findings offer a preclinical proof of concept for the use of B7-H3-targeted ultrasound molecular imaging as a tool to improve the diagnostic accuracy of breast cancer detection in patients.

  16. B7-H3 role in the immune landscape of cancer.

    PubMed

    Castellanos, Jose R; Purvis, Ian J; Labak, Collin M; Guda, Maheedhara R; Tsung, Andrew J; Velpula, Kiran K; Asuthkar, Swapna

    2017-01-01

    The field of immunotherapy is a continually expanding niche in cancer biology research. In the last two decades, there has been significant progress in identifying better targets and creating more specific agents for therapy in the field. B7-H3 (CD276) is an immune checkpoint from the B7 family of molecules, many of whom interact with known checkpoint markers including CTLA4, PD-1, and CD28. This is an exciting molecule that is overexpressed in many cancers, although the receptor of B7-H3 has not been characterized. Initially, B7-H3 was thought to co-stimulate the immune response, but recent studies have shown that it has a co-inhibitory role on T-cells, contributing to tumor cell immune evasion. Therefore, its overexpression has been linked to poor prognosis in human patients and to invasive and metastatic potential of tumors in in vitro models. Moreover, recent evidence has shown that B7-H3 influences cancer progression beyond the immune regulatory roles. In this review, we aim to characterize the roles of B7-H3 in different cancers, its relationship with other immune checkpoints, and its non-immunological function in cancer progression. Targeting B7-H3 in cancer treatment can reduce cell proliferation, progression, and metastasis, which may ultimately lead to improved therapeutic options and better clinical outcomes.

  17. Breast Cancer Detection by B7-H3 Targeted Ultrasound Molecular Imaging

    PubMed Central

    Bachawal, Sunitha V.; Jensen, Kristin C.; Wilson, Katheryne E.; Tian, Lu; Lutz, Amelie M.; Willmann, Jürgen K.

    2015-01-01

    Ultrasound complements mammography as an imaging modality for breast cancer detection, especially in patients with dense breast tissue, but its utility is limited by low diagnostic accuracy. One emerging molecular tool to address this limitation involves contrast-enhanced ultrasound using microbubbles targeted to molecular signatures on tumor neovasculature. In this study, we illustrate how tumor vascular expression of B7-H3 (CD276), a member of the B7 family of ligands for T cell co-regulatory receptors, can be incorporated into an ultrasound method that can distinguish normal, benign, precursor and malignant breast pathologies for diagnostic purposes. Through an immunohistochemical analysis of 248 human breast specimens, we found that vascular expression of B7-H3 was selectively and significantly higher in breast cancer tissues. B7-H3 immunostaining on blood vessels distinguished benign/precursors from malignant lesions with high diagnostic accuracy in human specimens. In a transgenic mouse model of cancer, the B7-H3-targeted ultrasound imaging signal was increased significantly in breast cancer tissues and highly correlated with ex vivo expression levels of B7-H3 on quantitative immunofluorescence. Our findings offer a preclinical proof of concept for the use of B7-H3-targeted ultrasound molecular imaging as a tool to improve the diagnostic accuracy of breast cancer detection in patients. PMID:25899053

  18. Tumor associated endothelial expression of B7-H3 predicts survival in ovarian carcinomas

    PubMed Central

    Zang, Xingxing; Sullivan, Peggy S; Soslow, Robert A; Waitz, Rebecca; Reuter, Victor E; Wilton, Andrew; Thaler, Howard T; Arul, Manonmani; Slovin, Susan F; Wei, Joyce; Spriggs, David R; Dupont, Jakob; Allison, James P

    2010-01-01

    B7-H3 and B7x are members of the B7 family of immune regulatory ligands that are thought to attenuate peripheral immune responses through co-inhibition. Previous studies have correlated their overexpression with poor prognosis and decreased tumor-infiltrating lymphocytes in various carcinomas including uterine endometrioid carcinomas, and mounting evidence supports an immuno-inhibitory role in ovarian cancer prognosis. We sought to examine the expression of B7-H3 and B7x in 103 ovarian borderline tumors and carcinomas and study associations with clinical outcome. Using immunohistochemical tissue microarray analysis on tumor specimens, we found that 93 and 100% of these ovarian tumors express B7-H3 and B7x, respectively, with expression found predominantly on cell membranes and in cytoplasm. In contrast, only scattered B7-H3- and B7x-positive cells were detected in non-neoplastic ovarian tissues. B7-H3 was also expressed in the endothelium of tumor-associated vasculature in 44% of patients, including 78% of patients with high-stage tumors (FIGO stages III and IV), nearly all of which were high-grade serous carcinomas, and 26% of patients with low-stage tumors (FIGO stages I and II; P<0.001), including borderline tumors. Analysis of cumulative survival time and recurrence incidence revealed that carcinomas with B7-H3-positive tumor vasculature were associated with a significantly shorter survival time (P=0.02) and a higher incidence of recurrence (P=0.03). The association between B7-H3-positive tumor vasculature and poor clinical outcome remained significant even when the analysis was limited to the high-stage subgroup. These results show that ovarian borderline tumors and carcinomas aberrantly express B7-H3 and B7x, and that B7-H3-positive tumor vasculature is associated with high-grade serous histological subtype, increased recurrence and reduced survival. B7-H3 expression in tumor vasculature may be a reflection of tumor aggressiveness and has diagnostic and

  19. B7-H3 Overexpression Predicts Poor Survival of Cancer Patients: A Meta-Analysis.

    PubMed

    Ye, Zhimeng; Zheng, Zhuojun; Li, Xiaodong; Zhu, Yuandong; Zhong, Zhaoping; Peng, Linrui; Wu, Yanyan

    2016-01-01

    B7-H3 exhibits altered expression in various cancers. However, the correlation between B7-H3 expression and prognosis of cancer patients remains controversial. Therefore, we elicit a meta-analysis to investigate the potential value of B7-H3 in the prognostic prediction in human cancers. We searched PubMed (last update by June 15th, 2016) to identify studies assessing the effect of B7-H3 on survival of cancer patients. Hazard ratios (HRs) for overall survival (OS), recurrence free survival (RFS) and progression-free survival (PFS) from individual studies were calculated and pooled by using a random-effect or fix-effect model, and heterogeneity and publication bias analyses were also performed. Data from 24 observational studies consisting of 4141 patients were summarized. An elevated baseline B7-H3 was significantly correlated with poor OS (pooled HR = 2.09; 95% CI =1.60-2.74; P < 0.001). Differences across subgroups of tumor type (P = 0.324), year of publication (P = 0.431), ethnicity (P = 0.940), source of HR (P = 0.145), analysis type (P = 0.178) and sample size (P = 0.909) were not significant. Furthermore, high B7-H3 expression also predicted a significantly poor RFS (pooled HR = 1.39; 95% CI = 1.11-1.75; P = 0.004) but not PFS. This meta-analysis clarifies that elevated B7-H3 expression is significantly associated with poor survival in cancer patients. © 2016 The Author(s) Published by S. Karger AG, Basel.

  20. Glycoprotein B7-H3 overexpression and aberrant glycosylation in oral cancer and immune response

    PubMed Central

    Chen, Jung-Tsu; Chen, Chein-Hung; Ku, Ko-Li; Hsiao, Michael; Chiang, Chun-Pin; Hsu, Tsui-Ling; Chen, Min-Huey; Wong, Chi-Huey

    2015-01-01

    The incidence and mortality rate of oral cancer continue to rise, partly due to the lack of effective early diagnosis and increasing environmental exposure to cancer-causing agents. To identify new markers for oral cancer, we used a sialylation probe to investigate the glycoproteins differentially expressed on oral cancer cells. Of the glycoproteins identified, B7 Homolog 3 (B7-H3) was significantly overexpressed in oral squamous cell carcinoma (OSCC), and its overexpression correlated with larger tumor size, advanced clinical stage, and low survival rate in OSCC patients. In addition, knockdown of B7-H3 suppressed tumor cell proliferation, and restoration of B7-H3 expression enhanced tumor growth. It was also found that the N-glycans of B7-H3 from Ca9-22 oral cancer cells contain the terminal α-galactose and are more diverse with higher fucosylation and better interaction with DC-SIGN [DC-specific intercellular adhesion molecule-3 (ICAM-3)–grabbing nonintegrin] and Langerin on immune cells than that from normal cells, suggesting that the glycans on B7-H3 may also play an important role in the disease. PMID:26438868

  1. B7-H4 expression in ovarian serous carcinoma: a study of 306 cases.

    PubMed

    Liang, Li; Jiang, Yi; Chen, Jun-Song; Niu, Na; Piao, Jin; Ning, Jing; Zu, Youli; Zhang, Jing; Liu, Jinsong

    2016-11-01

    The B7 family of immune costimulatory ligands is a group of cell surface proteins that bind to the surface receptors of lymphocytes to fine-tune immune responses. The aberrant expression of these proteins plays a key role in tumor immune evasion. Immunotherapy targeting certain B7 family members, including programmed death ligand 1, has proven quite effective in suppressing tumor growth. However, why such therapy works in only a subgroup of tumors is unclear. We hypothesized that other B7 family members, either alone or in concert with programmed death ligand 1, play a crucial role in tumor pathogenesis and progression. We therefore examined the expression of a newly discovered B7 family member, B7-H4, in 306 cases of ovarian serous carcinoma by immunohistochemistry. We found that 91% (267/293) of the high-grade ovarian serous carcinomas and 69% (9/13) of the low-grade ovarian serous carcinomas expressed B7-H4. The difference between B7-H4 expression in high-grade and low-grade ovarian serous carcinoma was statistically significant (P=.002). Moreover, B7-H4 protein expression in high-grade serous carcinoma was associated with tumor stage (P<.01) but not overall survival or disease-free survival. In conclusion, B7-H4 is frequently expressed in ovarian serous carcinomas, especially high-grade serous carcinomas, and may represent a novel immunotherapeutic target in this cancer.

  2. B7-H1 is a ubiquitous antiapoptotic receptor on cancer cells

    PubMed Central

    Azuma, Takeshi; Yao, Sheng; Zhu, Gefeng; Flies, Andrew S.; Flies, Sarah J.

    2008-01-01

    B7-H1 is an immunoglobulin-like immune suppressive molecule broadly detectable on the majority of human and rodent cancers, and its functions have been attributed to delivering an inhibitory signal to its counter-receptor programmed death-1 (PD-1) on T cells. Here we report that B7-H1 on cancer cells receives a signal from PD-1 to rapidly induce resistance against T cell–mediated killing because crippling signaling capacity of B7-H1 but not PD-1 ablates this resistance. Importantly, loss of B7-H1 signaling is accompanied by increased susceptibility to immune-mediated tumoricidal activity. In addition to resistance against T-cell destruction, B7-H1+ cancer cells also become refractory to apoptosis induced by Fas ligation or the protein kinase inhibitor Staurosporine. Our study reveals a new mechanism by which cancer cells use a receptor on immune cells as a ligand to induce resistance to therapy. PMID:18223165

  3. First principles centroid molecular dynamics simulation of hydride in nanoporous C12A7:H-

    NASA Astrophysics Data System (ADS)

    Ikeda, Takashi

    2017-05-01

    Hydrides in nanoporous [Ca24Al28O64]4+(H-)4 (C12A7:H-) were investigated via first principles centroid molecular dynamics (CMD). The quality of our CMD simulations was assessed by examining the temperature dependence of the distribution of hydrides in the cages constituting the C12A7 framework. The vibrational states of C12A7:H- were analyzed by using the trajectories of the centroids generated in our CMD simulations. We find that the rattling motions of H- and D- behave qualitatively differently, resulting in non-trivial isotope effects, which are suggested to be detectable by using infrared and Raman spectroscopy.

  4. Structure and T-cell inhibition properties of B7 family member, B7-H3

    PubMed Central

    Vigdorovich, Vladimir; Ramagopal, Udupi A.; Lázár-Molnár, Eszter; Sylvestre, Eliezer; Lee, Jun Sik; Hofmeyer, Kimberly A.; Zang, Xingxing; Nathenson, Stanley G.; Almo, Steven C.

    2013-01-01

    Summary T-cell activity is controlled by a combination of antigen-dependent signaling through the T-cell receptor and a set of auxiliary signals delivered through antigen-independent interactions, including the recognition of the B7 family of ligands. B7-H3 is a recently identified B7 family member that is strongly overexpressed in a range of cancers and correlates with poor prognosis. We report the crystal structure of murine B7-H3 at a 3-Å resolution, which provides a model for the organization of the IgV and IgC domains within the ectodomain. We demonstrate that B7-H3 inhibits T-cell proliferation and show that the FG loop of the IgV domain plays a critical role in this function. B7-H3 crystallized as an unusual dimer arising from the exchange of the G strands in the IgV domains of partner molecules. This arrangement, in combination with previous reports, highlights the dynamic nature and plasticity of the immunoglobulin fold. PMID:23583036

  5. Turbulence in Supercritical O2/H2 and C7H16/N2 Mixing Layers

    NASA Technical Reports Server (NTRS)

    Bellan, Josette; Harstad, Kenneth; Okong'o, Nora

    2003-01-01

    This report presents a study of numerical simulations of mixing layers developing between opposing flows of paired fluids under supercritical conditions, the purpose of the study being to elucidate chemical-species-specific aspects of turbulence. The simulations were performed for two different fluid pairs O2/H2 and C7H16/N2 at similar reduced initial pressures (reduced pressure is defined as pressure divided by critical pressure). Thermodynamically, O2/H2 behaves more nearly like an ideal mixture and has greater solubility, relative to C7H16/N2, which departs strongly from ideality. Because of a specified smaller initial density stratification, the C7H16/N2 layers exhibited greater levels of growth, global molecular mixing, and turbulence. However, smaller density gradients at the transitional state for the O2/H2 system were interpreted as indicating that locally, this system exhibits enhanced mixing as a consequence of its greater solubility and closer approach to ideality. These thermodynamic features were shown to affect entropy dissipation, which was found to be larger for O2/H2 and concentrated in high-density-gradient-magnitude regions that are distortions of the initial density-stratification boundary. In C7H16/N2, the regions of largest dissipation were found to lie in high-density-gradient-magnitude regions that result from mixing of the two fluids.

  6. Expression levels of B7-H3 and TLT-2 in human oral squamous cell carcinoma

    PubMed Central

    ZHANG, SHAN-SHAN; TANG, JING; YU, SHU-YI; MA, LI; WANG, FENG; XIE, SHU-LE; JIN, LONG; YANG, HONG-YU

    2015-01-01

    The aim of the present study was to investigate the role of immune regulatory molecules B7-H3 [also known as cluster of differentiation 276] and triggering receptor expressed on myeloid cell-like transcript-2 (TLT-2) in patients with oral squamous cell carcinoma (OSCC). Human OSCC samples were obtained from 76 patients (female, 32; male, 44; age range, 23–81 years; median age, 50.9 years) that underwent resection for OSCC at Peking University Shenzhen Hospital (Shenzhen, China) between 2007 and 2010. In addition, control oral mucosal samples were obtained from 76 healthy individuals (female, 36; male, 40; age range, 21–62 years; median age, 45.3 years) during wisdom tooth extraction. Protein and gene expression levels of B7-H3 and TLT-2 were determined by immunohistochemical analysis and reverse transcription-polymerase chain reaction (RT-PCR). In the healthy oral mucosa samples, B7-H3 expression was identified to be weak, while the expression of TLT-2 was only detected sporadically in the cell membrane and cytoplasm. By contrast, the two regulatory molecules were widely expressed in the aforementioned localizations in human OSCC specimens upon immunohistochemical examination. Furthermore, quantitative RT-PCR confirmed the presence of significantly higher B7-H3 and TLT-2 expression levels in OSCC specimens compared with the oral mucosa of healthy individuals. The significantly higher expression levels of B7-H3 and TLT-2 in human OSCC specimens may indicate an inhibitory role of these molecules in the antitumoral immune response. To investigate interactions between these two molecules and individual antitumoral immune response in OSCC patients, prospective clinical studies with an adequate sample size are required. PMID:26622626

  7. TGF-β1 promotes colorectal cancer immune escape by elevating B7-H3 and B7-H4 via the miR-155/miR-143 axis

    PubMed Central

    Zhu, Jianjie; Meng, Fanyi; Chen, Qi; Tao, Lihua; Li, Rui; Fu, Fengqing; Liu, Cuiping; Hu, Yuanjia; Wang, Weipeng; Zhang, Hongjian; Hua, Dong; Chen, Weichang; Zhang, Xueguang

    2016-01-01

    Transforming growth factor-beta 1 (TGF-β1) suppresses T cell function, promoting tumor immune escape. Yet, whether the depression of TGF-β1 on T cell function is mediated by co-inhibitory molecules B7-H3 and B7-H4 remains largely unclear. Here, we demonstrated that TGF-β1 elevated the expression of miR-155 in colorectal cancer cells through SMAD3 and SMAD4. The upregulated miR-155 attenuated miR-143 by inhibiting its direct target, the transcription factor CEBPB. Consequently, the direct target genes of miR-143, B7-H3 and B7-H4, were augmented in the cytoplasm and membrane of tumor cells. Over-expression of B7-H3 and B7-H4 in HCT-116 cells induced T cells to secrete TGF-β1 and the immunosuppressive cytokines IL-2, IL-6, and IL-17. Restoration of miR-143 inhibited the growth of HCT-116 xenograft tumors in mice, and also repressed the expression of B7-H3 and B7-H4 in the tumors. Thus, this study reveals the mechanism by which TGF-β1 leads to T cell-mediated tumor evasion through an increase in B7-H3 and B7-H4 expression. PMID:27626488

  8. Interval arithmetic in calculations

    NASA Astrophysics Data System (ADS)

    Bairbekova, Gaziza; Mazakov, Talgat; Djomartova, Sholpan; Nugmanova, Salima

    2016-10-01

    Interval arithmetic is the mathematical structure, which for real intervals defines operations analogous to ordinary arithmetic ones. This field of mathematics is also called interval analysis or interval calculations. The given math model is convenient for investigating various applied objects: the quantities, the approximate values of which are known; the quantities obtained during calculations, the values of which are not exact because of rounding errors; random quantities. As a whole, the idea of interval calculations is the use of intervals as basic data objects. In this paper, we considered the definition of interval mathematics, investigated its properties, proved a theorem, and showed the efficiency of the new interval arithmetic. Besides, we briefly reviewed the works devoted to interval analysis and observed basic tendencies of development of integral analysis and interval calculations.

  9. The Expression of B7-H3 Molecule in Periodontal Disease

    PubMed Central

    John, Saumya; Kurumathur, Arun; Talwar, Avaneendra; Kumar, Keerthana; Abraham, Teenu; Alagiri, Ananthi; Walaja, Gnanasagar; Clements, Jasmine

    2017-01-01

    Statement of the Problem: T cells have been shown to play a role in the etiopathogenesis of periodontal disease. B7-H3, a costimulatory molecule, is found to be associated with regulation of T cell function in some tumoral tissues, as well as autoimmune and inflammatory diseases. Purpose: The aim of this study was to investigate the expression of B7-H3 molecule in healthy and diseased gingival tissue samples. Materials and Method: Gingival samples were taken from 2 groups (A and B) representing periodontal health and periodontal disease, respectively. These were paraffinized and processed to carry out immunostaining to identify B7-H3 expression. The slides were then examined under light microscope to assess the positive staining in epithelium and connective tissue. The intensity of positive staining in epithelium and the number of positive cells in the connective tissue were evaluated. Statistical analysis was done using kappa analysis and independent t-test. Results: Kappa analysis revealed good inter-examiner agreement for both the groups (group A: 0.718; group B: 0.797). Intensity of staining in the epithelium ranged from intense to moderate for both the groups. In the connective tissue, there was a statistically insignificant decrease (p value= 0.415) in the number of positive cells from group A (mean labeling index: 50.28±26.09) to group B (mean labeling index= 41.37±25.29). Conclusion: B7-H3 molecule has been found to be expressed in gingival tissue samples; however, it showed a statistically insignificant decrease in periodontal disease group compared to healthy group. PMID:28293664

  10. Helicity in Supercritical O2/H2 and C7H16/N2 Mixing Layers

    NASA Technical Reports Server (NTRS)

    Okongo, Nora; Bellan, Josette

    2004-01-01

    This report describes a study of databases produced by direct numerical simulation of mixing layers developing between opposing flows of two fluids under supercritical conditions, the purpose of the study being to elucidate chemical-species-specific aspects of turbulence, with emphasis on helicity. The simulations were performed for two different fluid pairs -- O2/H2 and C7H16/N2 -- at similar values of reduced pressure.

  11. Artemether Regulates Chemosensitivity to Doxorubicin via Regulation of B7-H3 in Human Neuroblastoma Cells.

    PubMed

    Tan, Wei-Qiang; Chen, Gang; Ye, Ming; Jia, Bing

    2017-09-03

    BACKGROUND Artemether, originally used for malaria, exhibits potential therapeutic efficacy against several types of cancer, including gastric cancer, hepatocellular carcinoma, and gliomas. In this study, we investigated the role and mechanism of artemether on drug resistance of neuroblastoma cells. MATERIAL AND METHODS Cell viability and proliferation were determined by CCK-8 and EdU incorporation assay, respectively. Gene expression was measured by real-time PCR and Western blot analysis. RESULTS Our results revealed that artemether treatment remarkably inhibited the proliferation of neuroblastoma cell lines SH-SY5Y, SK-N-SH, and SK-N-BE2. In addition, co-treatment of tumor cells with artemether and doxorubicin significantly reduced cell viability and DNA synthesis compared with doxorubicin-treated cells. On the molecular level, we found that combined treatment with artemether and doxorubicin suppressed the expression of B7-H3 both at the mRNA and protein levels. In addition, artemether failed to sensitize tumor cells to doxorubicin in SH-SY5Y cells overexpressing B7-H3. CONCLUSIONS Artemether-mediated inhibition of B7-H3 may contribute to doxorubicin sensitivity in neuroblastoma cells, suggesting that artemether could serve as a potential therapeutic option for neuroblastoma.

  12. Thermal Decomposition of C7H7 Radicals; Benzyl, Tropyl, and Norbornadienyl

    NASA Astrophysics Data System (ADS)

    Buckingham, Grant; Ellison, Barney; Daily, John W.; Ahmed, Musahid

    2015-06-01

    Benzyl radical (C6H5CH2) and two other C7H7 radicals are commonly encountered in the combustion of substituted aromatic compounds found in biofuels and gasoline. High temperature pyrolysis of benzyl radical requires isomerization to other C7H7 radicals that may include cycloheptatrienyl (tropyl) radical (cyc-C7H7) and norbornadienyl radical. The thermal decomposition of all three radicals has now been investigated using a micro-reactor that heats dilute gas-phase samples up to 1600 K and has a residence time of about 100 μ-sec. The pyrolysis products exit the reactor into a supersonic expansion and are detected using synchrotron-based photoionization mass spectrometry and matrix-isolation IR spectroscopy. The products of the pyrolysis of benzyl radical (C6H5CH2) along with three isotopomers (C6H513CH2, C6D5CH2, and C6H5CD2) were detected and identified. The distribution of 13C atoms and D atoms indicate that multiple different decomposition pathways are active. Buckingham, G. T., Ormond, T. K., Porterfield, J. P., Hemberger, P., Kostko, O., Ahmed, M., Robichaud, D. J., Nimlos, M. R., Daily, J. W., Ellison, G. B. 2015, Journal of Chemical Physics 142 044307

  13. Sono-crystallization of ZnSO4 ṡ 7H20

    NASA Astrophysics Data System (ADS)

    Harzali, Hassen; Espitalier, Fabienne; Louisnard, Olivier; Mgaidi, Arbi

    2010-01-01

    Power ultrasound are known to enhance crystals nucleation, and nucleation times can be reduced by one up to three orders of magnitude for several organic or inorganic crystals. The precise mechanism of this phenomenon is yet unclear, but various theoretical explanations involve the action of inertial cavitation bubbles: cooling effect, pressure effect, segregation effect and evaporation effect. All these effects sound reasonable and may in fact act in a complementary fashion. The pressure effect is mediated by the high pressures appearing near the bubble as the latter collapses. The increase in pressure shifts the thermodynamical equilibrium. Zinc sulphate (ZnSO4ṡ7H2O) has the interesting property that its solubility is not sensitive to pressure. We therefore carried out experiments of ZnSO4ṡ7H2O crystallization by cooling in a 0.5 L crystallizer, both under silent conditions and by 20 W/cm2 insonification with a horn transducer. The induction time is found almost independent of supersaturation under ultrasound, and much lower than the one obtained in silent conditions for low supersaturation (0.021 g of ZnSO4ṡ7H2O/g solution). These experimental results question the generality of the pressure effect.

  14. Immune accessory functions of human endothelial cells are modulated by overexpression of B7-H1 (PDL1).

    PubMed

    LaGier, Adriana J; Pober, Jordan S

    2006-08-01

    B7-H1 (PDL1) is a B7-related protein that inhibits T-cell responses. Human endothelial cells (EC), which can support polyclonal stimulation (by anti-CD3 or Phytohemagglutinin (PHA)) or direct alloantigen stimulation of T cells, basally express B7-H1 and increase expression in response to IFN-gamma or coculture with allogeneic T cells. Previous studies have suggested that endogenous B7-H1 on EC reduces T-cell responses. We engineered overexpression of B7-H1 in EC (B7H1-EC) to evaluate whether this manipulation could reduce T-cell responses even further. Compared with green fluorescent protein-transduced EC (GFP-EC), B7H1-EC support less anti-CD3 or PHA-induced proliferation of CD4+ memory T cells; naive CD4+ T-cell or CD8+ T-cell responses were less inhibited. The effect of transduced B7H1-EC was more apparent when the EC were fixed prior to coculture, a manipulation that reduces the strength of costimulation and prevents upregulation of the endogenous B7-H1 molecule. T-cell activation markers, including CD25, CD62L, CD152 (CTLA-4), and CD154 (CD40L), were not altered by EC overexpression of B7-H1, whereas there was a reduction in CD69. B7-H1 reduced secretion of IL-2 and IL-10 by memory T cells. B7H1-EC were less able to stimulate allogeneic proliferation of CD4+ memory T cells than control EC. These data suggest that B7-H1 overexpression may be a useful approach for reducing allogeneic CD4+ memory T-cell responses to EC.

  15. The co-stimulatory molecule B7-H3 promotes the epithelial-mesenchymal transition in colorectal cancer

    PubMed Central

    Jiang, Bo; Zhang, Ting; Liu, Fen; Sun, Zhangzhang; Shi, Hanping; Hua, Dong; Yang, Chen

    2016-01-01

    B7-H3, first recognized as a co-stimulatory molecule, is abnormally expressed in cancer tissues and is associated with cancer metastasis and a poor prognosis. However, as an initial event of metastasis, the relationship between the Epithelial–Mesenchymal Transition (EMT) in cancer cells and B7-H3 has still not been investigated. In this study, we first analyzed B7-H3 expression by immunohistochemistry in colorectal cancer tissues. B7-H3 was expressed in the cancer cell membrane and was associated with the T stage of colorectal cancer; it also showed a positive correlation with MMP2 and MMP9 expression in cancer tissues. Over-expression of B7-H3 in SW480 cells allowed cancer cells to invade and metastasize more than the control cells, whereas invasion and metastasis capabilities were decreased after B7-H3 was knocked down in Caco-2 cells. We further showed that B7-H3 down-regulated the expression of E-cadherin and β-catenin and up-regulated N-cadherin and Vimentin expression, implying that B7-H3 promoted the EMT in colorectal cancer cells. We also checked another character of the EMT, the stemness of cancer cells. CD133, CD44 and Oct4 were significantly elevated after the SW480 cells were transfected with B7-H3 and reduced in Caco-2 cells after B7-H3 was inhibited. In subsequent studies, we proved that B7-H3 upregulated the expression of Smad1 via PI3K-Akt. In conclusion, B7-H3 promotes the EMT in colorectal cancer cells by activating the PI3K-Akt pathway and upregulating the expression of Smad1. PMID:27145365

  16. Inhibition of mouse SP2/0 myeloma cell growth by the B7-H4 protein vaccine.

    PubMed

    Mu, Nan; Liu, Nannan; Hao, Qiang; Xu, Yujin; Li, Jialin; Li, Weina; Wu, Shouzhen; Zhang, Cun; Su, Haichuan

    2014-07-01

    B7-H4 is a member of B7 family of co-inhibitory molecules and B7-H4 protein is found to be overexpressed in many human cancers and which is usually associated with poor survival. In this study, we developed a therapeutic vaccine made from a fusion protein composed of a tetanus toxoid (TT) T-helper cell epitope and human B7-H4IgV domain (TT-rhB7-H4IgV). We investigated the anti-tumor effect of the TT-rhB7-H4IgV vaccine in BALB/c mice and SP2/0 myeloma growth was significantly suppressed in mice. The TT-rhB7-H4IgV vaccine induced high-titer specific antibodies in mice. Further, the antibodies induced by TT-rhB7-H4IgV vaccine were capable of depleting SP2/0 cells through complement-dependent cytotoxicity (CDC) in vitro. On the other hand, the poor cellular immune response was irrelevant to the therapeutic efficacy. These results indicate that the recombinant TT-rhB7-H4IgV vaccine might be a useful candidate of immunotherapy for the treatment of some tumors associated with abnormal expression of B7-H4.

  17. An anti-B7-H4 antibody-drug conjugate for the treatment of breast cancer.

    PubMed

    Leong, Steven R; Liang, Wei-Ching; Wu, Yan; Crocker, Lisa; Cheng, Eric; Sampath, Deepak; Ohri, Rachana; Raab, Helga; Hass, Philip E; Pham, Thinh; Firestein, Ron; Li, Dongwei; Schutten, Melissa; Stagg, Nicola J; Ogasawara, Annie; Koppada, Neelima; Roth, Leslie; Williams, Simon P; Lee, Byoung-Chul; Chalouni, Cecile; Peng, Ivan; DeVoss, Jason; Tremayne, Jarrod; Polakis, Paul; Polson, Andrew G

    2015-06-01

    B7-H4 has been implicated in cancers of the female reproductive system and investigated for its possible use as a biomarker for cancer, but there are no preclinical studies to demonstrate that B7-H4 is a molecular target for therapeutic intervention of cancer. We provide evidence that the prevalence and expression levels of B7-H4 are high in different subtypes of breast cancer and that only a few normal tissues express B7-H4 on the cell membrane. These profiles of low normal expression and upregulation in cancer provide an opportunity for the use of antibody-drug conjugates (ADCs), cytotoxic drugs chemically linked to antibodies, for the treatment of B7-H4 positive cancers. We have developed an ADC specific to B7-H4 that uses a linker drug consisting of a potent antimitotic, monomethyl auristatin E (MMAE), linked to engineered cysteines (THIOMAB) via a protease labile linker. We will refer to ADCs that use the THIOMAB format as TDCs to help distinguish the format from standard MC-vc-MMAE ADCs that are conjugated to the interchain disulfide bonds. Anti-B7-H4 (h1D11)-MC-vc-PAB-MMAE (h1D11 TDC) produced durable tumor regression in cell line and patient-derived xenograft models of triple-negative breast cancer. It also binds rat B7-H4 with similar affinity to human and allowed us to test for target dependent toxicity in rats. We found that our anti-B7-H4 TDC has toxicity findings similar to untargeted TDC. Our results validate B7-H4 as an ADC target for breast cancer and support the possible use of this TDC in the treatment of B7-H4(+) breast cancer.

  18. Laboratory submillimeter transition frequencies of Li-7H and Li-6H. [used for abundance investigations in red giant stars

    NASA Technical Reports Server (NTRS)

    Plummer, G. M.; Herbst, E.; De Lucia, F. C.

    1984-01-01

    The fundamental (J = 1 - 0) rotational transition frequencies of Li-7H and Li-6H in their ground (v = 0) vibrational states and of Li-7H in its first excited (v = 1) vibrational state have been measured in the laboratory. Use of these transition frequencies should permit astronomical investigations of LiH abundances in red giant stars of high lithium abundance.

  19. The inhibitory role of b7-h4 in antitumor immunity: association with cancer progression and survival.

    PubMed

    He, Changjun; Qiao, Haiquan; Jiang, Hongchi; Sun, Xueying

    2011-01-01

    B7-H4 is one of the most recently identified members of B7 superfamily of costimulatory molecules serving as an inhibitory modulator of T-cell response. B7-H4 is broadly expressed in human peripheral tissues and inducibly expressed in immune cells. The expression of B7-H4 has been observed in various types of human cancer tissues, and its soluble form has been detected in blood samples from cancer patients. However, its precise physiological role is still elusive, as its receptor has not been identified and the expression levels are not consistent. This paper summarizes the pertinent data on the inhibitory role of B7-H4 in antitumor immunity and its association with cancer progression and survival in human patients. The paper also discusses the clinical significance of investigating B7-H4 as potential markers for cancer diagnosis and prognosis, and as therapeutic targets.

  20. Target-dependent B7-H1 regulation contributes to clearance of central nervous system infection and dampens morbidity.

    PubMed

    Phares, Timothy W; Ramakrishna, Chandran; Parra, Gabriel I; Epstein, Alan; Chen, Lieping; Atkinson, Roscoe; Stohlman, Stephen A; Bergmann, Cornelia C

    2009-05-01

    The neurotropic coronavirus JHM strain of mouse hepatitis virus persists in oligodendroglia despite the presence of virus-specific CD8 T cells. Expression of programmed death 1 (PD-1) and B7-H1 were studied during acute and persistent infection to examine whether this negative regulatory mechanism contributes to CNS viral persistence. The majority of CNS-infiltrating CD8 T cells expressed PD-1, with the highest levels on virus-specific CD8 T cells. Moreover, despite control of infectious virus, CD8 T cells within the CNS of persistently infected mice maintained high PD-1 expression. Analysis of virus-susceptible target cells in vivo revealed that B7-H1 expression was regulated in a cell type-dependent manner. Oligodendroglia and microglia up-regulated B7-H1 following infection; however, although B7-H1 expression on oligodendroglia was prominent and sustained, it was significantly reduced and transient on microglia. Infection of mice deficient in the IFN-gamma or IFN-alpha/beta receptor demonstrated that B7-H1 expression on oligodendroglia is predominantly regulated by IFN-gamma. Ab blockade of B7-H1 on oligodendroglia in vitro enhanced IFN-gamma secretion by virus-specific CD8 T cells. More efficient virus control within the CNS of B7-H1-deficient mice confirmed inhibition of CD8 T cell function in vivo. Nevertheless, the absence of B7-H1 significantly increased morbidity without altering demyelination. These data are the first to demonstrate glia cell type-dependent B7-H1 regulation in vivo, resulting in adverse effects on antiviral CD8 T cell function. However, the beneficial role of PD-1:B7-H1 interactions in limiting morbidity highlights the need to evaluate tissue-specific intervention strategies.

  1. Experimental study of resonance states in {sup 7}H and {sup 6}H

    SciTech Connect

    Caamano, M.; Mittig, W.; Savajols, H.; Demonchy, C. E.; Jurado, B.; Rejmund, F.; Rejmund, M.; Roussel-Chomaz, P.; Gillibert, A.; Obertelli, A.; Lemmon, R.; Wolski, R.

    2008-10-15

    The {sup 7}H and {sup 6}H nuclear systems were investigated via transfer reactions with a {sup 8}He beam at 15.4A MeV impinging in a {sup 12}C target. The experimental setup allowed a complete reconstruction of the reaction kinematics with the MAYA gas detector, based on the active-target concept, where the carbon atoms of the filling isobutane played also the role of reaction target. The {sup 7}H resonance was observed at 0.57{sub -0.21}{sup +0.42} MeV above the {sup 3}H+4n threshold with a width of 0.09{sub -0.06}{sup +0.94} MeV. The {sup 6}H system was formed at 2.91{sub -0.95}{sup +0.85} MeV with a resonance width of 1.52{sub -0.35}{sup +1.77} MeV. These results show the availability of nuclear structure information well outside the bounding limits, resulting in an extraordinary input to improve the present models and understanding of nuclear matter.

  2. Musical intervals in speech

    PubMed Central

    Ross, Deborah; Choi, Jonathan; Purves, Dale

    2007-01-01

    Throughout history and across cultures, humans have created music using pitch intervals that divide octaves into the 12 tones of the chromatic scale. Why these specific intervals in music are preferred, however, is not known. In the present study, we analyzed a database of individually spoken English vowel phones to examine the hypothesis that musical intervals arise from the relationships of the formants in speech spectra that determine the perceptions of distinct vowels. Expressed as ratios, the frequency relationships of the first two formants in vowel phones represent all 12 intervals of the chromatic scale. Were the formants to fall outside the ranges found in the human voice, their relationships would generate either a less complete or a more dilute representation of these specific intervals. These results imply that human preference for the intervals of the chromatic scale arises from experience with the way speech formants modulate laryngeal harmonics to create different phonemes. PMID:17525146

  3. Musical intervals in speech.

    PubMed

    Ross, Deborah; Choi, Jonathan; Purves, Dale

    2007-06-05

    Throughout history and across cultures, humans have created music using pitch intervals that divide octaves into the 12 tones of the chromatic scale. Why these specific intervals in music are preferred, however, is not known. In the present study, we analyzed a database of individually spoken English vowel phones to examine the hypothesis that musical intervals arise from the relationships of the formants in speech spectra that determine the perceptions of distinct vowels. Expressed as ratios, the frequency relationships of the first two formants in vowel phones represent all 12 intervals of the chromatic scale. Were the formants to fall outside the ranges found in the human voice, their relationships would generate either a less complete or a more dilute representation of these specific intervals. These results imply that human preference for the intervals of the chromatic scale arises from experience with the way speech formants modulate laryngeal harmonics to create different phonemes.

  4. Programming with Intervals

    NASA Astrophysics Data System (ADS)

    Matsakis, Nicholas D.; Gross, Thomas R.

    Intervals are a new, higher-level primitive for parallel programming with which programmers directly construct the program schedule. Programs using intervals can be statically analyzed to ensure that they do not deadlock or contain data races. In this paper, we demonstrate the flexibility of intervals by showing how to use them to emulate common parallel control-flow constructs like barriers and signals, as well as higher-level patterns such as bounded-buffer producer-consumer. We have implemented intervals as a publicly available library for Java and Scala.

  5. Interval Graph Limits

    PubMed Central

    Diaconis, Persi; Holmes, Susan; Janson, Svante

    2015-01-01

    We work out a graph limit theory for dense interval graphs. The theory developed departs from the usual description of a graph limit as a symmetric function W (x, y) on the unit square, with x and y uniform on the interval (0, 1). Instead, we fix a W and change the underlying distribution of the coordinates x and y. We find choices such that our limits are continuous. Connections to random interval graphs are given, including some examples. We also show a continuity result for the chromatic number and clique number of interval graphs. Some results on uniqueness of the limit description are given for general graph limits. PMID:26405368

  6. SIRT7, H3K18ac, and ELK4 Immunohistochemical Expression in Hepatocellular Carcinoma

    PubMed Central

    Lee, Hye Seung; Jung, Wonkyung; Lee, Eunjung; Chang, Hyeyoon; Choi, Jin Hyuk; Kim, Han Gyeom; Kim, Aeree; Kim, Baek-hui

    2016-01-01

    Background SIRT7 is one of the histone deacetylases and is NAD-dependent. It forms a complex with ETS-like transcription factor 4 (ELK4), which deacetylates H3K18ac and works as a transcriptional suppressor. Overexpression of SIRT7 and deacetylation of H3K18ac have been shown to be associated with aggressive clinical behavior in some cancers, including hepatocellular carcinoma (HCC). The present study investigated the immunohistochemical expression of SIRT7, H3K18ac, and ELK4 in hepatocellular carcinoma. Methods A total of 278 HCC patients were enrolled in this study. Tissue microarray blocks were made from existing paraffin-embedded blocks. Immunohistochemical expressions of SIRT7, H3K18ac and ELK4 were scored and analyzed. Results High SIRT7 (p = .034), high H3K18ac (p = .001), and low ELK4 (p = .021) groups were associated with poor outcomes. Age < 65 years (p = .028), tumor size ≥ 5 cm (p = .001), presence of vascular emboli (p = .003), involvement of surgical margin (p = .001), and high American Joint Committee on Cancer stage (III&V) (p < .001) were correlated with worse prognoses. In multivariate analysis, H3K18ac (p = .001) and ELK4 (p = .015) were the significant independent prognostic factors. Conclusions High SIRT7 expression with poor overall survival implies that deacetylation of H3K18ac contributes to progression of HCC. High H3K18ac expression with poor prognosis is predicted due to a compensation mechanism. In addition, high ELK4 expression with good prognosis suggests another role of ELK4 as a tumor suppressor beyond SIRT7’s helper. In conclusion, we could assume that the H3K18ac deacetylation pathway is influenced by many other factors. PMID:27498548

  7. Interval estimations in metrology

    NASA Astrophysics Data System (ADS)

    Mana, G.; Palmisano, C.

    2014-06-01

    This paper investigates interval estimation for a measurand that is known to be positive. Both the Neyman and Bayesian procedures are considered and the difference between the two, not always perceived, is discussed in detail. A solution is proposed to a paradox originated by the frequentist assessment of the long-run success rate of Bayesian intervals.

  8. Overconfidence in interval estimates.

    PubMed

    Soll, Jack B; Klayman, Joshua

    2004-03-01

    Judges were asked to make numerical estimates (e.g., "In what year was the first flight of a hot air balloon?"). Judges provided high and low estimates such that they were X% sure that the correct answer lay between them. They exhibited substantial overconfidence: The correct answer fell inside their intervals much less than X% of the time. This contrasts with choices between 2 possible answers to a question, which showed much less overconfidence. The authors show that overconfidence in interval estimates can result from variability in setting interval widths. However, the main cause is that subjective intervals are systematically too narrow given the accuracy of one's information-sometimes only 40% as large as necessary to be well calibrated. The degree of overconfidence varies greatly depending on how intervals are elicited. There are also substantial differences among domains and between male and female judges. The authors discuss the possible psychological mechanisms underlying this pattern of findings.

  9. Direct interval volume visualization.

    PubMed

    Ament, Marco; Weiskopf, Daniel; Carr, Hamish

    2010-01-01

    We extend direct volume rendering with a unified model for generalized isosurfaces, also called interval volumes, allowing a wider spectrum of visual classification. We generalize the concept of scale-invariant opacity—typical for isosurface rendering—to semi-transparent interval volumes. Scale-invariant rendering is independent of physical space dimensions and therefore directly facilitates the analysis of data characteristics. Our model represents sharp isosurfaces as limits of interval volumes and combines them with features of direct volume rendering. Our objective is accurate rendering, guaranteeing that all isosurfaces and interval volumes are visualized in a crack-free way with correct spatial ordering. We achieve simultaneous direct and interval volume rendering by extending preintegration and explicit peak finding with data-driven splitting of ray integration and hybrid computation in physical and data domains. Our algorithm is suitable for efficient parallel processing for interactive applications as demonstrated by our CUDA implementation.

  10. Spectroscopic Photoacoustic Molecular Imaging of Breast Cancer using a B7-H3-targeted ICG Contrast Agent

    PubMed Central

    Wilson, Katheryne E.; Bachawal, Sunitha V.; Abou-Elkacem, Lotfi; Jensen, Kristen; Machtaler, Steven; Tian, Lu; Willmann, Jürgen K.

    2017-01-01

    Purpose: Breast cancer imaging methods lack diagnostic accuracy, in particular for patients with dense breast tissue, and improved techniques are critically needed. The purpose of this study was to evaluate antibody-indocyanine green (ICG) conjugates, which undergo dynamic absorption spectrum shifts after cellular endocytosis and degradation, and spectroscopic photoacoustic (sPA) imaging to differentiate normal breast tissue from breast cancer by imaging B7-H3, a novel breast cancer associated molecular target. Methods: Quantitative immunohistochemical staining of endothelial and epithelial B7-H3 expression was assessed in 279 human breast tissue samples, including normal (n=53), benign lesions (11 subtypes, n=129), and breast cancers (4 subtypes, n=97). After absorption spectra of intracellular and degraded B7-H3-ICG and Isotype control-ICG (Iso-ICG) were characterized, sPA imaging in a transgenic murine breast cancer model (FVB/N-Tg(MMTVPyMT)634Mul) was performed and compared to imaging of control conditions [B7-H3-ICG in tumor negative animals (n=60), Iso-ICG (n=30), blocking B7-H3+B7-H3-ICG (n=20), and free ICG (n=20)] and validated with ex vivo histological analysis. Results: Immunostaining showed differential B7-H3 expression on both the endothelium and tumor epithelium in human breast cancer with an area under the ROC curve of 0.93 to differentiate breast cancer vs non-cancer. Combined in vitro/in vivo imaging showed that sPA allowed specific B7-H3-ICG detection down to the 13 nM concentration and differentiation from Iso-ICG. sPA molecular imaging of B7-H3-ICG showed a 3.01-fold (P<0.01) increase in molecular B7-H3-ICG signal in tumors compared to control conditions. Conclusions: B7-H3 is a promising target for both vascular and epithelial sPA imaging of breast cancer. Leveraging antibody-ICG contrast agents and their dynamic optical absorption spectra allows for highly specific sPA imaging of breast cancer. PMID:28529630

  11. Temperature Dependences for the Reactions of Ar+, O2+, and C7H7+ with Toluene and Ethylbenzene

    DTIC Science & Technology

    2013-07-01

    containing C7H7+. Products with 4, 5, 6, and 7 carbonswere found. The largest non-C7H7+ cation is C5H6+ at 3–4%. For reactions with known thermochemistry ...154201. 15] N.S. Shuman, T.M. Miller, A.A. Viggiano, J. Troe, Teaching an old dog new tricks: using the flowing afterglow to measure kinetics of electron

  12. The tumor suppressor miR-124 inhibits cell proliferation and invasion by targeting B7-H3 in osteosarcoma.

    PubMed

    Wang, Ling; Kang, Fu-Biao; Sun, Nan; Wang, Juan; Chen, Wei; Li, Dong; Shan, Bao-En

    2016-11-01

    Our previous studies have shown that the expression level of B7 homolog 3 (B7-H3) was correlated with clinical staging and prognosis of osteosarcoma (OS) patients, and its silencing inhibited the proliferation and invasion of OS cells in vitro. However, its overexpression mechanism behind was far from elucidated. On the basis of bioinformatics and the preliminary screening data, we hypothesized that miR-124 might play an important role in OS development and as a lead candidate for modulating B7-H3 expression. In this study, we found that miR-124 was downregulated significantly in OS tumor tissue, compared to normal adjacent tissues (NATs). Lower miR-124 expression levels were associated with advanced Ennecking stage, lower tumor differentiation, and common pulmonary metastasis. The 5-year overall survival rate in the miR-124 upregulated group was 61.5 %, while with low miR-124 expression, only 11.8 % survived. Further studies in vitro showed that B7-H3 was a direct target of miR-124. Overexpression of miR-124 decreased B7-H3 mRNA and protein level and inhibited B7-H3 3'-UTR reporter activity. Treatment of OS cells with miR-124 mimics induced the inhibition of cell growth and invasion in vitro, which could be abrogated by transfected by B7-H3 expression vector. Our findings highlight the potential application of miR-124 as a novel onco-miRNA in OS, and its oncogenic effects are mediated chiefly through downregulation of B7-H3, thus suggesting a model for identifying miR-124 that can be exploited to improve the therapeutic potential efficacy of mAb targeting to B7-H3.

  13. Assessment of plasma B7-H3 levels in pediatric patients with different degrees of surgical stress.

    PubMed

    Li, Yan; Yuan, Qing; Huang, Jie; Li, Yi Ping; Pan, Jian; Feng, Xing; Zhang, Xue Guang; Wang, Jiang Huai; Wang, Jian

    2016-07-26

    Surgical stress initiates a series of host hormone, metabolism and immune responses, which predominantly affect the homeostatic mechanism of patients with major surgery. B7-H3 is a co-stimulatory molecule and has been shown to participate in both adaptive and innate immune responses. In this study we evaluated the clinical significance of plasma B7-H3 levels in pediatric patients with different types of operation and degrees of surgical stress. A total of 48 children received pediatric general and cardiac surgery were recruited into this study. Based on the surgical stress scoring, children were divided into moderate stress (n = 14) and severe stress (n = 34) groups. Plasma B7-H3 levels were assessed at selected time points: before surgery, immediately after surgery, at day 1, day 3, and day 7 after surgery. Correlations between plasma B7-H3 levels and surgical stress scores were also examined. Plasma B7-H3 levels were significantly decreased in all 48 pediatric patients after surgery compared to the B7-H3 level before surgery (p < 0.01). Children with general surgery showed significant decreases in plasma B7-H3 immediately after surgery, and at day 3 and day 7 after surgery (p < 0.05, p < 0.01), whereas children with cardiac surgery showed reduced plasma B7-H3 immediately after surgery and at day 3 after surgery (p < 0.05). Plasma B7-H3 in cardiac surgery group was dropped much lower than that in general surgery group at day 1 (p < 0.05) and day 3 (p < 0.01) after surgery. Significantly reduced plasma B7-H3 was observed in the severe stress group, but not in the moderate stress group, immediately after surgery and at day 3 after surgery (p < 0.05), and severe stress group had significantly lower plasma B7-H3 levels than moderate stress group at day 1, day 3, and day 7 after surgery (p < 0.05). Furthermore, plasma B7-H3 levels at day 1 (p = 0.01) and day 3 (p = 0.025) after surgery correlated negatively with surgical

  14. Solution Dependence of the Collisional Activation of Ubiquitin [M+7H]7+ Ions

    PubMed Central

    Shi, Huilin; Atlasevich, Natalya; Merenbloom, Samuel I.; Clemmer, David E.

    2014-01-01

    The solution dependence of gas-phase unfolding for ubiquitin [M+7H]7+ ions has been studied by ion mobility spectrometry-mass spectrometry (IMS-MS). Different acidic water:methanol solutions are used to favor the native (N), more helical (A), or unfolded (U) solution states of ubiquitin. Unfolding of gas-phase ubiquitin ions is achieved by collisional heating and newly formed structures are examined by IMS. With an activation voltage of 100 V, a selected distribution of compact structures unfolds, forming three resolvable elongated states (E1-E3). The relative populations of these elongated structures depend strongly on the solution composition. Activation of compact ions from aqueous solutions known to favor N-state ubiquitin produces mostly the E1 type elongated state, whereas, activation of compact ions from methanol containing solutions that populate A-state ubiquitin favors the E3 elongated state. Presumably, this difference arises because of differences in precursor ion structures emerging from solution. Thus, it appears that information about solution populations can be retained after ionization, selection, and activation to produce the elongated states. These data as well as others are discussed. PMID:24658799

  15. B7-H1-expressing antigen-presenting cells mediate polarization of protumorigenic Th22 subsets.

    PubMed

    Kuang, Dong-Ming; Xiao, Xiao; Zhao, Qiyi; Chen, Min-Min; Li, Xue-Feng; Liu, Rui-Xian; Wei, Yuan; Ouyang, Fang-Zhu; Chen, Dong-Ping; Wu, Yan; Lao, Xiang-Ming; Deng, Hong; Zheng, Limin

    2014-10-01

    Classical IL-22-producing T helper cells (Th22 cells) mediate inflammatory responses independently of IFN-γ and IL-17; however, nonclassical Th22 cells have been recently identified and coexpress IFN-γ and/or IL-17 along with IL-22. Little is known about how classical and nonclassical Th22 subsets in human diseases are regulated. Here, we used samples of human blood, normal and peritumoral liver, and hepatocellular carcinoma (HCC) to delineate the phenotype, distribution, generation, and functional relevance of various Th22 subsets. Three nonclassical Th22 subsets constituted the majority of all Th22 cells in human liver and HCC tissues, although the classical Th22 subset was predominant in blood. Monocytes activated by TLR2 and TLR4 agonists served as the antigen-presenting cells (APCs) that most efficiently triggered the expansion of nonclassical Th22 subsets from memory T cells and classical Th22 subsets from naive T cells. Moreover, B7-H1-expressing monocytes skewed Th22 polarization away from IFN-γ and toward IL-17 through interaction with programmed death 1 (PD-1), an effect that can create favorable conditions for in vivo aggressive cancer growth and angiogenesis. Our results provide insight into the selective modulation of Th22 subsets and suggest that strategies to influence functional activities of inflammatory cells may benefit anticancer therapy.

  16. Growth morphology of epsomite (MgSO 4·7H 2O)

    NASA Astrophysics Data System (ADS)

    Rubbo, Marco; Aquilano, Dino; Franchini-Angela, Marinella; Sgualdino, Giulio

    1985-06-01

    A first approach to the study of the growth properties of epsomite (MgSO 4·7H 2O) is presented. Particular attention is payed to the growth forms and to epitaxy relations between epsomite and some known habit modifiers. The starting point of the study is the Hartman and Perdok PBC analysis. It proves to be essential for knowing the actual surface profiles. Successively the theoretical growth morphology is given taking into account: the broken-bond model of Wolff and Broder, the energies associated to the hydrogen bonds only, and finally the attachment energies calculated on the basis of the Coulomb potential. Furthermore an analysis of 2D coincidence lattices leads us to the conclusion that a 2D epitaxy of both Na 2B 4O 7·lOH 2O and/or Na 2SO 4·lOH 2O on {111} and/or ? forms of epsomite explains the effect of borax and Glauber's salt as habit modifiers.

  17. Subverting the B7-H1/PD-1 pathway in advanced melanoma and kidney cancer.

    PubMed

    Harshman, Lauren C; Choueiri, Toni K; Drake, Charles; Stephen Hodi, F

    2014-01-01

    Ligands for inhibitory immune receptors on T cells may be constitutively expressed on tumor cells or host cells in tumor microenvironment as a consequence of adaptive immunity. Programmed death 1 (PD-1) is 1 such receptor on T cells, which functions as a negative regulator of T cell activity. Tumors that up-regulate programmed death ligand 1 (PD-L1) (B7-H1) may abrogate the host's effector T cell antitumor response. Higher tumoral PD-L1 expression has been linked with inferior clinical outcomes. Multiple cancers including renal cell cancers (RCCs) and melanomas have relatively high levels of PD-L1 on the cell surface. Early evaluations of antibodies that block the interaction of PD-1 and PD-L1 have shown efficacy and a favorable tolerability profile with notable inflammatory toxicities that are generally manageable. Upward of 30% of RCC patients and 50% of melanoma patients achieve objective responses. Durable responses can occur, even in some patients who have discontinued treatment. The developing investigation of PD-1/PD-L1 pathway-blocking agents in RCC and melanoma will likely alter our approaches to the treatment of these 2 deadly diseases.

  18. Radiometric method for testing susceptibility of mycobacteria to pyrazinamide in 7H12 broth.

    PubMed Central

    Heifets, L B; Iseman, M D

    1985-01-01

    The test of susceptibility to pyrazinamide requires an acid environment (pH less than or equal to 5.5). This, however, is not favorable to the growth of Mycobacterium tuberculosis, especially in solid agar media. To obviate this difficulty, we developed a testing method with 7H12 broth medium and based on radiometric readings of the growth. The radiometric method employed in this study (BACTEC system) provides an opportunity to detect the dynamics of growth by daily recording of the growth index, which reflects the metabolic activity of the multiplying bacteria. In our technique, M. tuberculosis isolates were initially cultivated at pH 6.8. After logarithmic growth had begun, phosphoric acid solution was added to obtain pH 5.5. When pyrazinamide was added simultaneously with the acid, the growth index of susceptible cultures decreased, whereas it continued to increase in pH 5.5 control vials and in tests with pyrazinamide-resistant strains. PMID:3972987

  19. Prognostic role of high B7-H4 expression in patients with solid tumors: a meta-analysis

    PubMed Central

    Gu, Wendong; Xu, Chao; Mao, Huihui; Pei, Honglei; Jiang, Jingting

    2016-01-01

    Background Recently, many studies have shown that B7-H4 exhibits altered expression in various cancers. We performed a meta-analysis to evaluate the prognostic role of B7-H4 expression in solid tumors. Results Data from 18 observational studies and 2467 patients were summarized. An elevated baseline B7-H4 was significantly associated with worse OS (pooled HR = 1.79; 95% CI = 1.56–2.06). Differences across subgroups of tumor type, patients' ethnicity, analysis type, HR obtain method and cut-off value were not significant (PD = 0.313, PD = 0.716, PD = 0.896, PD = 0.290 and PD = 0.153, respectively). Furthermore, patients with high B7-H4 had a significantly shorter DFS (pooled HR = 2.12; 95%CI = 1.45–3.09). Materials and Methods We searched PubMed, Embase and the Cochrane Library (last update by November 26, 2015) to identify studies assessing the effect of B7-H4 on survival of cancer patients. Pooled hazard ratios (HRs) for overall survival (OS) and disease-free survival (DFS) were estimated using fixed-effects models and random-effects models respectively. Conclusions This meta-analysis clarified that high B7-H4 expression in tissue was significantly associated with poor survival in patients with solid tumors. Future clinical studies are warranted to determine whether B7-H4 blockade has a favorable effect on disease recurrence and mortality. PMID:27058425

  20. Interval neural networks

    SciTech Connect

    Patil, R.B.

    1995-05-01

    Traditional neural networks like multi-layered perceptrons (MLP) use example patterns, i.e., pairs of real-valued observation vectors, ({rvec x},{rvec y}), to approximate function {cflx f}({rvec x}) = {rvec y}. To determine the parameters of the approximation, a special version of the gradient descent method called back-propagation is widely used. In many situations, observations of the input and output variables are not precise; instead, we usually have intervals of possible values. The imprecision could be due to the limited accuracy of the measuring instrument or could reflect genuine uncertainty in the observed variables. In such situation input and output data consist of mixed data types; intervals and precise numbers. Function approximation in interval domains is considered in this paper. We discuss a modification of the classical backpropagation learning algorithm to interval domains. Results are presented with simple examples demonstrating few properties of nonlinear interval mapping as noise resistance and finding set of solutions to the function approximation problem.

  1. B7-H1 (PD-L1, CD274) suppresses host immunity in T-cell lymphoproliferative disorders.

    PubMed

    Wilcox, Ryan A; Feldman, Andrew L; Wada, David A; Yang, Zhi-Zhang; Comfere, Nneka I; Dong, Haidong; Kwon, Eugene D; Novak, Anne J; Markovic, Svetomir N; Pittelkow, Mark R; Witzig, Thomas E; Ansell, Stephen M

    2009-09-03

    Stromal elements present within the tumor microenvironment may suppress host immunity and promote the growth of malignant lymphocytes in B cell-derived non-Hodgkin lymphoma (NHL). In contrast, little is known about the microenvironment's role in T cell-derived NHL. B7-H1 (PD-L1, CD274), a member of the B7 family of costimulatory/co-inhibitory ligands expressed by both malignant cells and stromal cells within the tumor microenvironment, has emerged as an important immune modulator capable of suppressing host immunity. Therefore, B7-H1 expression and function were analyzed in cutaneous and peripheral T-cell NHL. B7-H1 was expressed by tumor cells, monocytes, and monocyte-derived cells within the tumor microenvironment in T-cell NHL and was found to inhibit T-cell proliferation and promote the induction of FoxP3(+) regulatory T cells. Collectively, the data presented provide the first evidence implicating B7-H1 in the suppression of host immunity in T-cell lymphoproliferative disorders and suggest that the targeting of B7-H1 may represent a novel therapeutic approach.

  2. Structure of the Human Activating Natural Cytotoxicity Receptor NKp30 Bound to its Tumor Cell Ligand B7-H6

    SciTech Connect

    Y Li; Q Wang; R Mariuzza

    2011-12-31

    Natural killer (NK) cells are lymphocytes of the innate immune system that participate in the elimination of tumor cells. In humans, the activating natural cytotoxicity receptors (NCRs) NKp30, NKp44, and NKp46 play a major role in NK cell-mediated tumor cell lysis. NKp30 recognizes B7-H6, a member of the B7 family which is expressed on tumor, but not healthy, cells. To understand the basis for tumor surveillance by NCRs, we determined the structure of NKp30, a member of the CD28 family which includes CTLA-4 and PD-1, in complex with B7-H6. The overall organization of the NKp30-B7-H6-activating complex differs considerably from those of the CTLA-4-B7 and PD-1-PD-L T cell inhibitory complexes. Whereas CTLA-4 and PD-1 use only the front {beta}-sheet of their Ig-like domain to bind ligands, NKp30 uses both front and back {beta}-sheets, resulting in engagement of B7-H6 via the side, as well as face, of the {beta}-sandwich. Moreover, B7-H6 contacts NKp30 through the complementarity-determining region (CDR) - like loops of its V-like domain in an antibody-like interaction that is not observed for B7 or PD-L. This first structure of an NCR bound to ligand provides a template for designing molecules to stimulate NKp30-mediated cytolytic activity for tumor immunotherapy.

  3. B7-H1 antibodies lose antitumor activity due to activation of p38 MAPK that leads to apoptosis of tumor-reactive CD8+ T cells

    PubMed Central

    Liu, Xin; Wu, Xiaosheng; Cao, Siyu; Harrington, Susan M.; Yin, Peng; Mansfield, Aaron S.; Dong, Haidong

    2016-01-01

    B7-H1 (aka PD-L1) blocking antibodies have been used in treatment of human cancers through blocking B7-H1 expressed by tumor cells; however, their impact on B7-H1 expressing tumor-reactive CD8+ T cells is still unknown. Here, we report that tumor-reactive CD8+ T cells expressing B7-H1 are functional effector cells. In contrast to normal B7-H1 blocking antibody, B7-H1 antibodies capable of activating p38 MAPK lose their antitumor activity by deleting B7-H1+ tumor-reactive CD8+ T cells via p38 MAPK pathway. B7-H1 deficiency or engagement with certain antibody results in more activation of p38 MAPK that leads to T cell apoptosis. DNA-PKcs is a new intracellular partner of B7-H1 in the cytoplasm of activated CD8+ T cells. B7-H1 suppresses p38 MAPK activation by sequestering DNA-PKcs in order to preserve T cell survival. Our findings provide a new mechanism of action of B7-H1 in T cells and have clinical implications in cancer immunotherapy when anti-B7-H1 (PD-L1) antibody is applied. PMID:27824138

  4. Overconfidence in Interval Estimates

    ERIC Educational Resources Information Center

    Soll, Jack B.; Klayman, Joshua

    2004-01-01

    Judges were asked to make numerical estimates (e.g., "In what year was the first flight of a hot air balloon?"). Judges provided high and low estimates such that they were X% sure that the correct answer lay between them. They exhibited substantial overconfidence: The correct answer fell inside their intervals much less than X% of the time. This…

  5. Decreased expression of B7-H3 reduces the glycolytic capacity and sensitizes breast cancer cells to AKT/mTOR inhibitors

    PubMed Central

    Nunes-Xavier, Caroline E.; Karlsen, Karine Flem; Tekle, Christina; Pedersen, Cathrine; Øyjord, Tove; Hongisto, Vesa; Nesland, Jahn M.; Tan, Ming; Sahlberg, Kristine Kleivi; Fodstad, Øystein

    2016-01-01

    B7 family proteins are important immune response regulators, and can mediate oncogenic signaling and cancer development. We have used human triple-negative breast cancer cell lines with different expression levels of B7-H3 to evaluate its effects on the sensitivity to 22 different anticancer compounds in a drug screen. API-2 (triciribidine) and everolimus (RAD-001), two inhibitors that target the PI3K/AKT/mTOR pathway, showed enhanced inhibition of cell viability and proliferation in B7-H3 knockdown tumor cells compared to their B7-H3 expressing counterparts. Similar inhibition was seen in control cells treated with an anti-B7-H3 monoclonal antibody. In B7-H3 overexpressing cells, the effects of the two drugs were reduced, supported also by in vivo experiments in which B7-H3 overexpressing xenografts were less sensitive to everolimus than control tumors. In API-2 and everolimus-treated B7-H3 overexpressing cells, phospho-mTOR levels were decreased. However, phosphorylation of p70S6K was differentially regulated in B7-H3 cells treated with API-2 or everolimus, suggesting a different B7-H3-mediated mechanism downstream of mTOR. Both API-2 and everolimus decreased the glycolysis of the cells, whereas knockdown of B7-H3 decreased and B7-H3 overexpression increased the glycolytic capacity. In conclusion, we have unveiled a previously unknown relationship between B7-H3 expression and glycolytic capacity in tumor cells, and found that B7-H3 confers resistance to API-2 and everolimus. The results provide novel insights into the function of B7-H3 in cancer, and suggest that targeting of B7-H3 may be a novel alternative to improve current anticancer therapies. PMID:26771843

  6. Varieties of Confidence Intervals.

    PubMed

    Cousineau, Denis

    2017-01-01

    Error bars are useful to understand data and their interrelations. Here, it is shown that confidence intervals of the mean (CI M s) can be adjusted based on whether the objective is to highlight differences between measures or not and based on the experimental design (within- or between-group designs). Confidence intervals (CIs) can also be adjusted to take into account the sampling mechanisms and the population size (if not infinite). Names are proposed to distinguish the various types of CIs and the assumptions underlying them, and how to assess their validity is explained. The various CIs presented here are easily obtained from a succession of multiplicative adjustments to the basic (unadjusted) CI width. All summary results should present a measure of precision, such as CIs, as this information is complementary to effect sizes.

  7. Uncertainty analysis of integrated gasification combined cycle systems based on Frame 7H versus 7F gas turbines.

    PubMed

    Zhu, Yunhua; Frey, H Christopher

    2006-12-01

    Integrated gasification combined cycle (IGCC) technology is a promising alternative for clean generation of power and coproduction of chemicals from coal and other feedstocks. Advanced concepts for IGCC systems that incorporate state-of-the-art gas turbine systems, however, are not commercially demonstrated. Therefore, there is uncertainty regarding the future commercial-scale performance, emissions, and cost of such technologies. The Frame 7F gas turbine represents current state-of-practice, whereas the Frame 7H is the most recently introduced advanced commercial gas turbine. The objective of this study was to evaluate the risks and potential payoffs of IGCC technology based on different gas turbine combined cycle designs. Models of entrained-flow gasifier-based IGCC systems with Frame 7F (IGCC-7F) and 7H gas turbine combined cycles (IGCC-7H) were developed in ASPEN Plus. An uncertainty analysis was conducted. Gasifier carbon conversion and project cost uncertainty are identified as the most important uncertain inputs with respect to system performance and cost. The uncertainties in the difference of the efficiencies and costs for the two systems are characterized. Despite uncertainty, the IGCC-7H system is robustly preferred to the IGCC-7F system. Advances in gas turbine design will improve the performance, emissions, and cost of IGCC systems. The implications of this study for decision-making regarding technology selection, research planning, and plant operation are discussed.

  8. Origination of new immunological functions in the costimulatory molecule B7-H3: the role of exon duplication in evolution of the immune system.

    PubMed

    Sun, Jing; Fu, Fengqing; Gu, Wenchao; Yan, Ruhong; Zhang, Guangbo; Shen, Zhiyong; Zhou, Yinghui; Wang, Han; Shen, Bairong; Zhang, Xueguang

    2011-01-01

    B7-H3, a recently identified B7 family member, has different isoforms in human and mouse. Mouse B7-H3 gene has only one isoform (2IgB7-H3) with two Ig-like domains, whereas human B7-H3 has two isoforms (2IgB7-H3 and 4IgB7-H3). In this study a systematic genomic survey across various species from teleost fishes to mammals revealed that 4IgB7-H3 isoform also appeared in pigs, guinea pigs, cows, dogs, African elephants, pandas, megabats and higher primate animals, which resulted from tandem exon duplication. Further sequence analysis indicated that this duplication generated a new conserved region in the first IgC domain, which might disable 4IgB7-H3 from releasing soluble form, while 2IgB7-H3 presented both membrane and soluble forms. Through three-dimensional (3D) structure modeling and fusion-protein binding assays, we discovered that the duplicated isoform had a different structure and might bind to another potential receptor on activated T cells. In T cell proliferation assay, human 2IgB7-H3 (h2IgB7-H3) and mouse B7-H3 (mB7-H3) both increased T cell proliferation and IL-2, IFN-γ production, whereas human 4IgB7-H3 (h4IgB7-H3) reduced cytokine production and T cell proliferation compared to control. Furthermore, both h2IgB7-H3 and mB7-H3 upregulated the function of lipopolysacharide (LPS)-activated monocyte in vitro. Taken together, our data implied that during the evolution of vertebrates, B7-H3 exon duplication contributed to the generation of a new 4IgB7-H3 isoform in many mammalian species, which have carried out distinct functions in the immune responses.

  9. Multichannel interval timer (MINT)

    SciTech Connect

    Kimball, K.B.

    1982-06-01

    A prototype Multichannel INterval Timer (MINT) has been built for measuring signal Time of Arrival (TOA) from sensors placed in blast environments. The MINT is intended to reduce the space, equipment costs, and data reduction efforts associated with traditional analog TOA recording methods, making it more practical to field the large arrays of TOA sensors required to characterize blast environments. This document describes the MINT design features, provides the information required for installing and operating the system, and presents proposed improvements for the next generation system.

  10. Interval probabilistic neural network.

    PubMed

    Kowalski, Piotr A; Kulczycki, Piotr

    2017-01-01

    Automated classification systems have allowed for the rapid development of exploratory data analysis. Such systems increase the independence of human intervention in obtaining the analysis results, especially when inaccurate information is under consideration. The aim of this paper is to present a novel approach, a neural networking, for use in classifying interval information. As presented, neural methodology is a generalization of probabilistic neural network for interval data processing. The simple structure of this neural classification algorithm makes it applicable for research purposes. The procedure is based on the Bayes approach, ensuring minimal potential losses with regard to that which comes about through classification errors. In this article, the topological structure of the network and the learning process are described in detail. Of note, the correctness of the procedure proposed here has been verified by way of numerical tests. These tests include examples of both synthetic data, as well as benchmark instances. The results of numerical verification, carried out for different shapes of data sets, as well as a comparative analysis with other methods of similar conditioning, have validated both the concept presented here and its positive features.

  11. Synergistic effects of host B7-H4 deficiency and gemcitabine treatment on tumor regression and anti-tumor T cell immunity in a mouse model.

    PubMed

    Leung, Joanne; St-Onge, Philippe; Stagg, John; Suh, Woong-Kyung

    2017-04-01

    B7-H4 (B7x/B7S1), a B7 family inhibitor of T cell activity, is expressed in multiple human cancers and correlates with decreased infiltrating lymphocytes and poor prognosis. In murine models, tumor-expressed B7-H4 enhances tumor growth and reduces T cell immunity, and blockade of tumor-B7-H4 rescues T cell activity and lowers tumor burden. This implicates B7-H4 as a target for cancer immunotherapy, yet limits the efficacy of B7-H4 blockade exclusively to patients with B7-H4+ tumors. Given the expression of B7-H4 on host immune cells, we have previously shown that BALB/c mice lacking host B7-H4 have enhanced anti-tumor profiles, yet similar 4T1 tumor growth relative to control. Given that T cell-mediated immunotherapies work best for tumors presenting tumor-associated neoantigens, we further investigated the function of host B7-H4 in the growth of a more immunogenic derivative, 4T1-12B, which is known to elicit strong anti-tumor CD8 T cell responses due to expression of a surrogate tumor-specific antigen, firefly luciferase. Notably, B7-H4 knockout hosts not only mounted greater tumor-associated anti-tumor T cell responses, but also displayed reduced tumors. Additionally, B7-H4-deficiency synergized with gemcitabine to further inhibit tumor growth, often leading to tumor eradication and the generation of protective T cell immunity. These findings imply that inhibition of host B7-H4 can enhance anti-tumor T cell immunity in immunogenic cancers, and can be combined with other anti-cancer therapies to further reduce tumor burden regardless of tumor-B7-H4 positivity.

  12. Effect of Taiwan mutation (D7H) on structures of amyloid-β peptides: replica exchange molecular dynamics study.

    PubMed

    Truong, Phan Minh; Viet, Man Hoang; Nguyen, Phuong H; Hu, Chin-Kun; Li, Mai Suan

    2014-07-31

    Recent experiments have shown that the Taiwan mutation (D7H) slows the fibril formation of amyloid peptides Aβ40 and Aβ42. Motivated by this finding, we have studied the influence of D7H mutation on structures of Aβ peptide monomers using the replica exchange molecular dynamics simulations with OPLS force field and implicit water model. Our study reveals that the mechanism behind modulation of aggregation rates is associated with decrease of β-content and dynamics of the salt bridge D23-K28. Estimating the bending free energy of this salt bridge, we have found that, in agreement with the experiments, the fibril formation rate of both peptides Aβ40 and Aβ42 is reduced about two times by mutation.

  13. Optimization of modified Middlebrook 7H11 agar for isolation of Mycobacterium bovis from raw milk cheese.

    PubMed

    Forgrave, R; Donaghy, J A; Fisher, A; Rowe, M T

    2014-10-01

    Reports have highlighted the absence of contemporary peer reviewed publications pertaining to Mycobacterium bovis culture from raw milk and cheese. By replicating traditional methods, cheese-making methodology and equipment were devised to produce Cheddar (n = 6) and Caerphilly (n = 3) artificially contaminated with M. bovis (three genotypes) under stringent laboratory-containment guidelines for handling hazardous microbiological material. Middlebrook 7H11, modified for M. bovis isolation, was assessed for capacity to enumerate M. bovis despite changing cheese microflora and prolonged M. bovis exposure to the cheese matrix using maturing cheese test portions (n = 63; up to 16 weeks). Malachite green (MG) containing media isolated M. bovis at significantly (P < 0·05) lower levels than unmodified Middlebrook 7H11 agar despite MG being a common adjunct of Middlebrook 7H11 agar modified for M. bovis growth. Subsequently, a selective MG-free Middlebrook 7H11 agar modified using haemolysed red cells and calf serum was demonstrated as the best performing (P < 0·05) medium for recovery of M. bovis from typical UK cheese types, Cheddar and Caerphilly. Significance and impact of the study: Following increased M. bovis infection of UK cattle, the risk posed to consumers from consumption of unpasteurized milk and dairy products has changed. Furthermore, published methods for the culture and molecular detection of M. bovis in raw milk products are limited. Cheese-making protocols and M. bovis culture media reported here provide tools for further investigation of M. bovis survival during all stages of cheese manufacture and could inform future assessment of the risk to consumers from M. bovis contamination of unpasteurized dairy products.

  14. Differing metabolic responses to salt stress in wheat-barley addition lines containing different 7H chromosomal fragments

    PubMed Central

    Gierczik, Krisztián; Hudák, Orsolya; Forgó, Péter; Pál, Magda; Türkösi, Edina; Kovács, Viktória; Dulai, Sándor; Majláth, Imre; Molnár, István; Janda, Tibor; Molnár-Láng, Márta

    2017-01-01

    Salinity-induced osmotic, ionic and oxidative stress responses were investigated on Asakaze/Manas wheat/barley addition lines 7H, 7HL and 7HS, together with their barley (salt-tolerant) and wheat (relatively salt-sensitive) parents. Growth, photosynthetic activity, chlorophyll degradation, proline, glycine betaine accumulation, sugar metabolism, Na+ and K+ uptake and transport processes and the role of polyamines and antioxidants were studied in young plants grown in hydroponic culture with or without salt treatment. Changes in plant growth and photosynthetic activity of plants demonstrated that the salt tolerance of the addition lines 7H and 7HL was similar to that of barley parent cv. Manas, while the sensitivity of the addition line 7HS was similar to that of the wheat parent cv. Asakaze. The Na accumulation in the roots and shoots did not differ between the addition lines and wheat parent. The activation of various genes related to Na uptake and transport was not correlated with the salt tolerance of the genotypes. These results indicated that the direct regulation of Na transport processes is not the main reason for the salt tolerance of these genotypes. Salt treatment induced a complex metabolic rearrangement in both the roots and shoots of all the genotypes. Elevated proline accumulation in the roots and enhanced sugar metabolism in the shoots were found to be important for salt tolerance in the 7H and 7HL addition lines and in barley cv. Manas. In wheat cv. Asakaze and the 7HS addition line the polyamine metabolism was activated. It seems that osmotic adjustment is a more important process in the improvement of salt tolerance in 7H addition lines than the direct regulation of Na transport processes or antioxidant defence. PMID:28328973

  15. SiO2 Film Etching Process Using Environment-Friendly New Gas C5F7H

    NASA Astrophysics Data System (ADS)

    Miyawaki, Yudai; Takeda, Keigo; Ito, Azumi; Nakamura, Masahiro; Sekine, Makoto; Hori, Masaru

    2009-10-01

    With the continuous miniaturization of semiconductor memory devices, a much precise etching process for a high aspect ratio contact hole in SiO2 film is indispensable. Furthermore, deterioration of the SiO2 selectivity over a fragile, thin ArF photoresist would cause the sidewall roughness and poor pattern-width definition. In this study, we utilized a newly designed C5F7H gas. We compared the etch performances between the new gas and conventional C5F8 . Ar and O2 were introduced with the each fluorocarbon gas to controll the etching rate. A dual frequency (60 MHz / 2 MHz) capacitively coupled plasma was employed. The SiO2 etching rate and selectivity to ArF photoresist were investigated as a function of O2 flow rate. The maximum selectivity of only 3.7 and the SiO2 etching rate of 416 nm/min were obtained at O2 flow rate of 20 sccm for the C5F8/O2/Ar plasma. For the newly developed C5F7H/O2/Ar plasma, the maximum selectivity of 13.5 with the etching rate of 356 nm/min was achieved at 25-sccm O2 flow rate. From these results, it was confirmed that almost four times higher selectivity than that of the conventional C5F8 gas was obtained by using the new C5F7H gas.

  16. Synthesis and characterization of PVP/TbL(phen)0.5 x 7H2O nanorods.

    PubMed

    Cui, Zhenfeng; Ren, Huijuan; Sun, Dehui; Yang, Mei; Hong, Guangyan

    2011-11-01

    The luminescent complex terbium (III)-trimesic acid (TMA)-1,10-phenanthroline (phen) nanorod was synthesized in the polyvinylpyrrolidone (PVP) matrix by a co-precipitation method. The chemical formula of the synthesized complex was speculated to be PVP/TbL(phen)0.5 x 7H2O by inductively coupled plasma-atomic emission spectroscopy (ICP-AES), elemental analysis and Fourier-transform infrared spectroscopy (FTIR). The X-ray diffraction pattern (XRD) of PVP/TbL(phen)0.5 x 7H2O indicated that it was a crystalline complex. The transmission electron microscopy (TEM) result showed that the complex was nanorods with diameters of about 80-100 nm. The thermogravimetric curve (TGA) analysis exhibited that the complex has good stability below 400 degrees C. UV-Vis diffuse reflectance spectra showed that there is a maximum absorption at 300 nm. The photoluminescence analyses (PLA) showed that the synthesized complex emitted the characteristic green fluorescence of Tb (III) ions under ultraviolet light excitation. The emission peaks of PVP/TbL(phen)0.5 x 7H2O at 488, 542, 581, and 618 nm using 278 nm as exciting wavelength can be assigned to the 5D4 --> 7F6, 5D4 --> 7F5, 5D4 --> 7F4, and 5D4 --> 7F3 electron transitions of the Tb3+ ions, respectively.

  17. Enhanced antiviral T cell function in the absence of B7-H1 is insufficient to prevent persistence but exacerbates axonal bystander damage during viral encephalomyelitis.

    PubMed

    Phares, Timothy W; Stohlman, Stephen A; Hinton, David R; Atkinson, Roscoe; Bergmann, Cornelia C

    2010-11-01

    The T cell inhibitory ligand B7-H1 hinders T cell-mediated virus control, but also ameliorates clinical disease during autoimmune and virus-induced CNS disease. In mice infected with gliatropic demyelinating coronavirus, B7-H1 expression on oligodendroglia delays virus control, but also dampens clinical disease. To define the mechanisms by which B7-H1 alters pathogenic outcome, virus-infected B7-H1-deficient (B7-H1(-/-)) mice were analyzed for altered peripheral and CNS immune responses. B7-H1 deficiency did not affect peripheral T or B cell activation or alter the magnitude or composition of CNS-infiltrating cells. However, higher levels of IFN-γ mRNA in CNS-infiltrating virus-specific CD8 T cells as well as CD4 T cells contributed to elevated IFN-γ protein in the B7-H1(-/-) CNS. Increased effector function at the single-cell level was also evident by elevated granzyme B expression specifically in virus-specific CNS CD8 T cells. Although enhanced T cell activity accelerated virus control, 50% of mice succumbed to infection. Despite enhanced clinical recovery, surviving B7-H1(-/-) mice still harbored persisting viral mRNA, albeit at reduced levels compared with wild-type mice. B7-H1(-/-) mice exhibited extensive loss of axonal integrity, although demyelination, a hallmark of virus-induced tissue damage, was not increased. The results suggest that B7-H1 hinders viral control in B7-H1 expressing glia cells, but does not mediate resistance to CD8 T cell-mediated cytolysis. These data are the first, to our knowledge, to demonstrate that B7-H1-mediated protection from viral-induced immune pathology associated with encephalomyelitis resides in limiting T cell-mediated axonal bystander damage rather than direct elimination of infected myelinating cells.

  18. Interval hypoxic training.

    PubMed

    Bernardi, L

    2001-01-01

    Interval hypoxic training (IHT) is a technique developed in the former Soviet Union, that consists of repeated exposures to 5-7 minutes of steady or progressive hypoxia, interrupted by equal periods of recovery. It has been proposed for training in sports, to acclimatize to high altitude, and to treat a variety of clinical conditions, spanning from coronary heart disease to Cesarean delivery. Some of these results may originate by the different effects of continuous vs. intermittent hypoxia (IH), which can be obtained by manipulating the repetition rate, the duration and the intensity of the hypoxic stimulus. The present article will attempt to examine some of the effects of IH, and, whenever possible, compare them to those of typical IHT. IH can modify oxygen transport and energy utilization, alter respiratory and blood pressure control mechanisms, induce permanent modifications in the cardiovascular system. IHT increases the hypoxic ventilatory response, increase red blood cell count and increase aerobic capacity. Some of these effects might be potentially beneficial in specific physiologic or pathologic conditions. At this stage, this technique appears interesting for its possible applications, but still largely to be explored for its mechanisms, potentials and limitations.

  19. Effects of lung cancer cell-associated B7-H1 on T-cell proliferation in vitro and in vivo

    PubMed Central

    Chen, K.; Huang, H.T.; Hang, W.J.; Pan, L.B.; Ma, H.T.

    2016-01-01

    B7 homolog 1 (B7-H1) is the most potent immunoinhibitory molecule in the B7 family. In this study, we examined the effects of tumor-associated B7-H1 on T-cell proliferation in lung cancer. The expression of B7-H1 in human adenocarcinoma A549 and mouse Lewis lung carcinoma (LLC) cells were examined by flow cytometry. To assess the in vitro effect of tumor-associated B7-H1 on T-cell proliferation, we isolated T cells from peripheral blood mononuclear cells (PBMCs) of healthy individuals, labeled them with carboxyfluorescein succinimidyl ester, and co-cultured them with A549 cells in the absence or presence of anti-B7-H1 antibody. For in vivo analysis, LLC cells were subcutaneously injected into mice treated or not with anti-B7-H1 antibody. T-cell proliferation in both in vitro and in vivo assays was analyzed by flow cytometry. In vitro, co-culturing T cells with A549 cells significantly inhibited the proliferation of the former compared with the proliferation of T cells alone (P<0.01), and the addition of B7-H1 blocking antibody dramatically reversed the inhibition of T-cell proliferation by A549 cells. Similarly, in mice bearing LLC-derived xenograft tumors, in vivo administration of anti-B7-H1 antibody significantly increased the total number of spleen and tumor T cells compared to levels in control mice that did not receive anti-B7-H1 antibody. Functionally, in vivo administration of anti-B7-H1 antibody markedly reduced tumor growth. Tumor-associated B7-H1 may facilitate immune evasion by inhibiting T-cell proliferation. Targeting of this mechanism offers a promising therapy for cancer immunotherapy. PMID:27332773

  20. Myeloid-Derived Suppressor Cells (MDSC) Protect Islet Transplants via B7-H1 Mediated Enhancement of T Regulatory Cells

    PubMed Central

    Chou, Hong-Shiue; Hsieh, Ching-Chuan; Charles, Ronald; Wang, Lianfu; Wagner, Timothy; Fung, John J.; Qian, Shiguang; L, Lina Lu

    2011-01-01

    Background Side effects of lifetime immunosuppression for cell transplants often outweigh the benefits, therefore, induction of transplant tolerance is needed. We have shown that cotransplantation with myeoid-derived suppressor cells (MDSC) effectively protect islet allografts from rejection without requirement of immunosuppression. This study was to investigate the underlying mechanisms. Methods MDSC were generated by addition of hepatic stellate cells (HpSC) from various stain mice into dendritic cell (DC) culture. The quality of MDSC was monitored by phenotype and function analyses. MDSC mixed with islet allografts were transplanted into diabetic recipients. T cell response was analyzed following transplant by flow and histochemical analyses, and compared to islet alone and islet/DC transplant groups. B7-H1 knockout mice were used to determine the role of B7-H1 on MDSC in regulation of T cell response. Results Cotransplantation with MDSC (not DC) effectively protected islet allografts without requirement of immunosuppression. This is associated with attenuation of CD8 T cells in the grafts and marked expansion of T regulatory (Treg) cells, which contributed to MDSC-induced T cell hyporesponsiveness. Antigen-specific Treg cells were prone to accumulate in lymphoid organs close to the grafts. Both in vitro and in vivo data demonstrated that B7-H1 was absolutely required for MDSC to exert immune regulatory activity and induction of Treg cells. Conclusion The described approach holds great clinical application potential, and may overcome the limitation of requiring chronic administration of immunosuppression in cell transplants. Understanding the underlying mechanisms will facilitate the development of this novel therapeutic strategy. PMID:22179405

  1. Human Immunodeficiency Virus Type-1 Myeloid Derived Suppressor Cells Inhibit Cytomegalovirus Inflammation through Interleukin-27 and B7-H4

    PubMed Central

    Garg, Ankita; Trout, Rodney; Spector, Stephen A.

    2017-01-01

    HIV/CMV co-infected persons despite prolonged viral suppression often experience persistent immune activation, have an increased frequency of myeloid derived suppressor cells (MDSC) and are at increased risk for cardiovascular disease. We examined how HIV MDSC control CD4+ T cell IFNγ response to a CMVpp65 peptide pool (CMVpp65). We show that HIV/CMV co-infected persons with virologic suppression and recovered CD4+ T cells compared to HIV(−)/CMV(+) controls exhibit an increase in CD4+CX3CR1+IFNγ+ cells in response to CMVpp65; MDSC depletion further augmented CD4+CX3CR1+IFNγ+ cells and IFNγ production. IL-2 and IFNγ in response to CMVpp65 were enhanced with depletion of MDSC expanded in presence of HIV (HIV MDSC), but decreased with culture of HIV MDSC with autologous PBMCs. CMVpp65 specific CD4+CX3CR1+IFNγ+ cells were also decreased in presence of HIV MDSC. HIV MDSC overexpressed B7-H4 and silencing B7-H4 increased the production of IL-2 and IFNγ from autologous cells; a process mediated through increased phosphorylated (p)-Akt upon stimulation with CMVpp65. Additionally, IL-27 regulated the expression of B7-H4 on HIV MDSC, and controlled CMV-specific T cell activity by limiting CMVpp65-IFNγ production and expanding CD4+IL-10+ regulatory T cells. These findings provide new therapeutic targets to control the chronic immune activation and endothelial cell inflammation observed in HIV-infected persons. PMID:28338007

  2. Electron Paramagnetic Resonance of Cu2+ Doped Na2 HAsO4·7H2O Single Crystals

    NASA Astrophysics Data System (ADS)

    Köksal, F.; Kartal, İ.; Gençten, A.

    1998-09-01

    The electron paramagnetic resonance spectra of Cu2+ doped Na2HAsO4 ·7H2O single crystals were studied at room temperature. The results indicate the substitutional entrance of Cu2+ in two magnetically inequivalent Na+ sites. Charge compensation is supposed to be fulfilled by proton vacancies. The spin Hamiltonian parameters were determined. The ground state for Cu2+ seems to indicate the dominance of the dz² orbital and therefore a compression of the distorted octahedron along its C4v axis.

  3. Potential mosquito repellent compounds of Ocimum species against 3N7H and 3Q8I of Anopheles gambiae.

    PubMed

    Gaddaguti, Venugopal; Venkateswara Rao, Talluri; Prasada Rao, Allu

    2016-06-01

    Mosquitoes are exceptionally efficient in detecting their hosts for blood meal using odorant binding proteins, viz. 3N7H and 3Q8I and spread several dreadful diseases. DEET is a synthetic mosquito repellent widely used all over world for protection against mosquito bite. Reports reveal that, synthetic mosquito repellents may pose health problems in considerably large population. In view of the above fact, we made an attempt to discover efficient and novel natural mosquito repellent compounds with least impact on human health. Methanolic leaf extracts of Ocimum basilicum Linn. var. pilosum (willd.)-Benth and Ocimum tenuiflorum var. CIM-AYU were subjected to GC-MS analysis and obtained 35 phytochemical constituents. Repellent potentiality of the Ocimum compounds was assessed against 3Q8I and 3N7H of Anopheles gambiae. PDB structures of mosquito odorant binding proteins were downloaded, processed and docking studies were performed along with reference ligand DEET using Schrodinger MAESTRO 9.2 software. Molecular docking results reveal that phenol, 2-methoxy-3-(2-propenyl)-, licopersin, gamma sitosterol and benzene, 1,2-dimethoxy-4-(2-propenyl)- from O. tenuiflorum var. CIM-AYU are strongly bound with 3N7H. Whereas, 4h-1-benzopyran-4-one, 5-hydroxy-6,7-dimethoxy-2-(4-methoxyphenyl)-, catechol and monoacetin from O. basilicum Linn. var. pilosum (willd.)-Benth. show high binding affinity with odorant binding protein 3Q8I. All natural compounds tested in the present study display better docking scores than DEET. The results further substantiate that the 12 out of 35 compounds of the two Ocimum species found to be ideal candidates for design and development of potential mosquito repellents. ADME properties of the tested compounds further confirm that bioactive compounds of Ocimum species were found to be in acceptable range. Synchronized application of at least two different natural compounds (with best docking scores) which target 3N7H and 3Q8I (Odorant Binding Proteins

  4. B7-H3 regulates migration and invasion in salivary gland adenoid cystic carcinoma via the JAK2/STAT3 signaling pathway

    PubMed Central

    Fan, Teng-Fei; Deng, Wei-Wei; Bu, Lin-Lin; Wu, Tian-Fu; Zhang, Wen-Feng; Sun, Zhi-Jun

    2017-01-01

    B7 Homolog 3 (B7-H3), a newly identified member of the B7 family, is over-expressed in various human cancers and plays a vital role in tumor progression. To identify the expression pattern of B7-H3 in human salivary adenoid cystic carcinoma (AdCC) and its underlying mechanisms, we characterized B7-H3 expression in AdCC tissue microarrays using immunohistochemical staining, and analyzed potentially associated molecules. The results showed that B7-H3 was highly expressed in salivary AdCC, compared with normal salivary glands. Statistical analyses of immunohistochemical staining showed that B7-H3 was closely correlated with Slug and p-STAT3. Functional studies showed that knockdown of B7-H3 in AdCC cell lines using RNA interference did not influence cell growth and apoptosis, but decreased migration and invasion in vitro. Further mechanism studies suggested that B7-H3 influenced the migration and invasion of AdCC cells by regulating the epithelial-mesenchymal transition via JAK2/STAT3 pathway components. Collectively, these findings suggested that B7-H3 may be a potential therapeutic target for AdCC. PMID:28386362

  5. B7-H3 Promotes the Migration and Invasion of Human Bladder Cancer Cells via the PI3K/Akt/STAT3 Signaling Pathway

    PubMed Central

    Li, Yuchao; Guo, Guoning; Song, Jie; Cai, Zhiping; Yang, Jin; Chen, Zhiwen; Wang, Yun; Huang, Yaqin; Gao, Qiangguo

    2017-01-01

    Bladder cancer is one of most common malignant cancer. Although previous studies have found abnormal expression of B7-H3 in human bladder cancer tissues, the exact role and molecular mechanism of B7-H3 in bladder cancer remain unknown. In this study, we first detected the expression of B7-H3 in human bladder cancer samples and cell lines, and analyzed its correlations with clinicopathological pathological parameters. Next, siRNAs or overexpression plasmids of B7-H3 were transfected into T24 or 5637 cells, and cell proliferation, apoptosis, migration and invasion were analyzed via CCK-8, colony formation, flow cytometry and transwell assays, protein expression levels were determined by western blotting. The results presented here showed B7-H3 was upregulated in bladder cancer samples compared with normal tissues, and the expression level was correlated with local invasion status. B7-H3 did not affect cell proliferation and apoptosis, but cell migration and invasion were changed through the regulation of matrix metalloproteinase (MMP) 2/9. Knockdown of B7-H3 resulted in decreased activity of the STAT3 and PI3K/Akt pathways, and the Akt served as an upstream regulator of the STAT3. Our results suggest that the overexpression of B7-H3 promotes the migration and invasion of human bladder cancer cells through the PI3K/Akt/STAT3 signaling pathway. PMID:28382144

  6. Therapy to target renal cell carcinoma using 131I-labeled B7-H3 monoclonal antibody

    PubMed Central

    Li, Xueqin; Zhang, Guangbo; Hou, Jianquan

    2016-01-01

    B7-H3 is a tumor-associated antigen that plays a critical role in potential tumor-targeted therapy. In this study, we aimed to assess the radiobiological effect of 131I-labeled B7-H3 monoclonal antibody (131I-4H7) in nude mice with human renal cell carcinoma (RCC) and evaluate the effect of 131I-4H7 on RCC treatment. The radiobiological activity and tumor uptake of 131I-4H7, and its effect on tumor growth were measured. 131I-4H7 was absorbed by the tumor and reached its maximal uptake rate (3.32% injected dose [ID]/g) at 24 h, at which point the drug concentration in the tumor was 7.36-, 2.06-, 1.80-, and 2.78-fold higher than that in muscle, kidneys, liver, and heart, respectively. Measurements and positron emission tomography–computed tomography imaging showed that tumor development was significantly inhibited by 131I-4H7. HE staining revealed that 131I-4H7 significantly injures tumor cells. Our results suggest that 131I-4H7 is markedly absorbed by the tumor and did suppress the development of RCC xenografted tumors in nude mice, which might provide a new candidate for antibody-mediated targeted radiotherapy in human RCC. PMID:27058890

  7. Mesenchymal stem cells suppress T cells by inducing apoptosis and through PD-1/B7-H1 interactions.

    PubMed

    Yan, Zhidong; Zhuansun, Yongxun; Liu, Guirong; Chen, Rui; Li, Jianguo; Ran, Pixin

    2014-11-01

    Mesenchymal stem cells (MSCs) exert a suppressive role toward T cells which has been widely studied in recent decades. However, the underlying mechanisms utilized by MSCs are still not fully elucidated. Herein, we performed traditional suppressive assays using co-cultured MSCs and conventional CD4(+)CD25(-) T cells (Tconv) with and without transwell systems. We showed that the expression of programmed cell death-1 receptor (PD-1) on activated Tconv was significantly elevated after they were exposed to MSCs. And we demonstrated that PD-1/B7-H1 pathway was involved in the suppression of MSCs on activated Tconv. Further analysis revealed that the up-regulation of PD-1 was related to an increasing apoptosis of activated Tconv. Finally, we demonstrated that the PD-1/B7-H1 pathway was not related to the elevated immunosuppressive cytokines including IL-10 and TGF-β1 which in turn played dispensable roles in the up-regulation of PD-1 on activated Tconv in MSC-Tconv co-culture systems.

  8. Dimer-formation in the bis(arene)chromium fulleride Cr(C7H8)2 C60

    NASA Astrophysics Data System (ADS)

    Hönnerscheid, Andreas; van Wüllen, Leo; Jansen, Martin; Rahmer, Jürgen; Mehring, Michael

    2001-10-01

    Bis(toluene)chromium fulleride Cr(C7H8)2 C60 has been synthesized as a microcrystalline powder from C60 and Cr(C7H8)2 in toluene. One electron is transferred from the chromium complex to the fullerene resulting in a magnetic moment of about 2.5±0.2μB at room temperature, which corresponds to two electron spins per formula unit. At 250 K a reversible phase transition from a primitive cubic high temperature paramagnetic phase to a triclinic low temperature dimer phase occurs. The high temperature phase (Pm3¯m, a=9.986 Å) is constituted of dynamically disordered fulleride anions and bis(toluene)chromium (I) cations in a CsCl-type arrangement. The low temperature modification is triclinic (P1¯, a=13.541 Å, b=13.864 Å, c=14.122 Å, α=120.59, β=91.78, γ=116.88) and carries one unpaired electron per formula unit (μ=1.72±0.01 μB), which according to ESR measurements is localized at the chromium site (giso=1.9870). The phase transition has been monitored by x-ray diffraction, ESR and solid state NMR spectroscopy as well as by SQUID measurements. All experimental results can consistently be described within the scenario of dimer formation of the C60 monoanions during the transformation.

  9. Minimax confidence intervals in geomagnetism

    NASA Technical Reports Server (NTRS)

    Stark, Philip B.

    1992-01-01

    The present paper uses theory of Donoho (1989) to find lower bounds on the lengths of optimally short fixed-length confidence intervals (minimax confidence intervals) for Gauss coefficients of the field of degree 1-12 using the heat flow constraint. The bounds on optimal minimax intervals are about 40 percent shorter than Backus' intervals: no procedure for producing fixed-length confidence intervals, linear or nonlinear, can give intervals shorter than about 60 percent the length of Backus' in this problem. While both methods rigorously account for the fact that core field models are infinite-dimensional, the application of the techniques to the geomagnetic problem involves approximations and counterfactual assumptions about the data errors, and so these results are likely to be extremely optimistic estimates of the actual uncertainty in Gauss coefficients.

  10. Minimax confidence intervals in geomagnetism

    NASA Technical Reports Server (NTRS)

    Stark, Philip B.

    1992-01-01

    The present paper uses theory of Donoho (1989) to find lower bounds on the lengths of optimally short fixed-length confidence intervals (minimax confidence intervals) for Gauss coefficients of the field of degree 1-12 using the heat flow constraint. The bounds on optimal minimax intervals are about 40 percent shorter than Backus' intervals: no procedure for producing fixed-length confidence intervals, linear or nonlinear, can give intervals shorter than about 60 percent the length of Backus' in this problem. While both methods rigorously account for the fact that core field models are infinite-dimensional, the application of the techniques to the geomagnetic problem involves approximations and counterfactual assumptions about the data errors, and so these results are likely to be extremely optimistic estimates of the actual uncertainty in Gauss coefficients.

  11. Effect Sizes, Confidence Intervals, and Confidence Intervals for Effect Sizes

    ERIC Educational Resources Information Center

    Thompson, Bruce

    2007-01-01

    The present article provides a primer on (a) effect sizes, (b) confidence intervals, and (c) confidence intervals for effect sizes. Additionally, various admonitions for reformed statistical practice are presented. For example, a very important implication of the realization that there are dozens of effect size statistics is that "authors must…

  12. Temporal binding of interval markers

    PubMed Central

    Derichs, Christina; Zimmermann, Eckart

    2016-01-01

    How we estimate the passage of time is an unsolved mystery in neuroscience. Illusions of subjective time provide an experimental access to this question. Here we show that time compression and expansion of visually marked intervals result from a binding of temporal interval markers. Interval markers whose onset signals were artificially weakened by briefly flashing a whole-field mask were bound in time towards markers with a strong onset signal. We explain temporal compression as the consequence of summing response distributions of weak and strong onset signals. Crucially, temporal binding occurred irrespective of the temporal order of weak and strong onset markers, thus ruling out processing latencies as an explanation for changes in interval duration judgments. If both interval markers were presented together with a mask or the mask was shown in the temporal interval center, no compression occurred. In a sequence of two intervals, masking the middle marker led to time compression for the first and time expansion for the second interval. All these results are consistent with a model view of temporal binding that serves a functional role by reducing uncertainty in the final estimate of interval duration. PMID:27958311

  13. Reference Intervals in Neonatal Hematology.

    PubMed

    Henry, Erick; Christensen, Robert D

    2015-09-01

    The various blood cell counts of neonates must be interpreted in accordance with high-quality reference intervals based on gestational and postnatal age. Using very large sample sizes, we generated neonatal reference intervals for each element of the complete blood count (CBC). Knowledge of whether a patient has CBC values that are too high (above the upper reference interval) or too low (below the lower reference interval) provides important insights into the specific disorder involved and in many instances suggests a treatment plan. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. A novel subset of B7-H3(+)CD14(+)HLA-DR(-/low) myeloid-derived suppressor cells are associated with progression of human NSCLC.

    PubMed

    Zhang, Guangbo; Huang, Haitao; Zhu, Yibei; Yu, Gehua; Gao, Xin; Xu, Yunyun; Liu, Cuiping; Hou, Jianquan; Zhang, Xueguang

    2015-02-01

    Myeloid-derived suppressor cells (MDSC) potently inhibit antitumor immune responses, and thereby promoti tumor progression and metastasis. However, the nature of human tumor-infiltrating MDSC remains poorly characterized. Here, we find B7-H3 is exclusively expressed on a subset of intratumoral CD14(+)HLA-DR(-/low) MDSC but absent from adjacent normal lung tissues of patients with non-small cell lung carcinoma (NSCLC). Cytokine analysis revealed that B7-H3(+)CD14(+)HLA-DR(-/low) MDSC (B7-H3(+)MDSC) produced higher levels of IL-10 and TNFα but lower levels of IL-1β and IL-6 when compared with B7-H3(-)CD14(+)HLA-DR(-/low) myeloid-derived suppressor cells (B7-H3(-)MDSC). In a murine lung cancer model, B7-H3(+)MDSCs were found only in the tumor microenvironment and their frequencies increased during tumor progression. Clinical data analysis indicated that a higher frequency of B7-H3(+)MDSCs was associated with reduced recurrence-free survival in patients with NSCLC. Taken together, we identify a novel subset of MDSCs within the tumor microenvironment that fosters tumor progression.

  15. B7-H3 participates in the development of Asthma by augmentation of the inflammatory response independent of TLR2 pathway

    PubMed Central

    Gu, Wenjing; Zhang, Xinxing; Yan, Yongdong; Wang, Yuqing; Huang, Li; Wang, Meijuan; Shao, Xuejun; Chen, Zhengrong; Ji, Wei

    2017-01-01

    B7-H3, a new member of the B7 superfamily, acts as both a T cell costimulator and coinhibitor. Recent studies identified B7-H3 plays a critical role in the development of asthma. But the definitive mechanism is not clear. In this study, we further report that B7-H3 participates in the development of OVA-induced asthma in a murine model. And study its mechanism through the vitro and vivo experiment. Exogenous administration of B7-H3 strongly amplified the inflammatory response and augmented proinflammatory cytokines in vitro and vivo. These B7-H3–associated proinflammatory effects were not dependent on TLR2 signaling, as airway inflammation, eosinophils infiltration and cytokins (IL-4, IL-5, IL-13 and IFN-gamma) augment were still amplified in TLR2-deficient mice after administrated recombinant mouse B7-H3. These results indicated an important role for B7-H3 in the development of Th1 and Th2 cells in a murine model of asthma and its proinflammatory effects are not dependent on TLR2 signaling. PMID:28094276

  16. B7-H4 reverse signaling induces the apoptosis of EBV-transformed B cells through Fas ligand up-regulation.

    PubMed

    Song, Hyunkeun; Park, Gabin; Kim, Yeong-Seok; Hur, Indo; Kim, Hyunjin; Ryu, Jeoung Whan; Lee, Hyun-Kyung; Cho, Dae-Ho; Choi, In-Hak; Lee, Wang Jae; Hur, Dae Young

    2008-08-08

    B7-H4 has an inhibitory effect on immune responses via the down-regulation of T cell-mediated immunity, but how the engagement of B7-H4 molecules by counter molecules affects the signaling mechanism of the B7-H4-expressing cells is poorly defined. In this study, we found that B7-H4 expression was enhanced on B cells infected with Epstein-Barr virus (EBV) and that triggering of these molecules induced apoptosis of EBV-transformed B cells. Engagement of B7-H4 initially increased intracellular level of ROS, which then induced the expression of FasL. Engagement of B7-H4 subsequently provoked Fas-mediated and caspase-dependent apoptosis in association with cytochrome c and AIF, and EndoG was released from the mitochondria on EBV-transformed B cells. These results suggest that B7-H4 may be a potential therapeutic target for EBV involved malignancy diseases.

  17. Eradication of Tumors through Simultaneous Ablation of CD276/B7-H3-Positive Tumor Cells and Tumor Vasculature.

    PubMed

    Seaman, Steven; Zhu, Zhongyu; Saha, Saurabh; Zhang, Xiaoyan M; Yang, Mi Young; Hilton, Mary Beth; Morris, Karen; Szot, Christopher; Morris, Holly; Swing, Deborah A; Tessarollo, Lino; Smith, Sean W; Degrado, Sylvia; Borkin, Dmitry; Jain, Nareshkumar; Scheiermann, Julia; Feng, Yang; Wang, Yanping; Li, Jinyu; Welsch, Dean; DeCrescenzo, Gary; Chaudhary, Amit; Zudaire, Enrique; Klarmann, Kimberly D; Keller, Jonathan R; Dimitrov, Dimiter S; St Croix, Brad

    2017-04-10

    Targeting the tumor vasculature with antibody-drug conjugates (ADCs) is a promising anti-cancer strategy that in order to be realized must overcome several obstacles, including identification of suitable targets and optimal warheads. Here, we demonstrate that the cell-surface protein CD276/B7-H3 is broadly overexpressed by multiple tumor types on both cancer cells and tumor-infiltrating blood vessels, making it a potentially ideal dual-compartment therapeutic target. In preclinical studies CD276 ADCs armed with a conventional MMAE warhead destroyed CD276-positive cancer cells, but were ineffective against tumor vasculature. In contrast, pyrrolobenzodiazepine-conjugated CD276 ADCs killed both cancer cells and tumor vasculature, eradicating large established tumors and metastases, and improving long-term overall survival. CD276-targeted dual-compartment ablation could aid in the development of highly selective broad-acting anti-cancer therapies. Published by Elsevier Inc.

  18. Teaching Confidence Intervals Using Simulation

    ERIC Educational Resources Information Center

    Hagtvedt, Reidar; Jones, Gregory Todd; Jones, Kari

    2008-01-01

    Confidence intervals are difficult to teach, in part because most students appear to believe they understand how to interpret them intuitively. They rarely do. To help them abandon their misconception and achieve understanding, we have developed a simulation tool that encourages experimentation with multiple confidence intervals derived from the…

  19. Explorations in Statistics: Confidence Intervals

    ERIC Educational Resources Information Center

    Curran-Everett, Douglas

    2009-01-01

    Learning about statistics is a lot like learning about science: the learning is more meaningful if you can actively explore. This third installment of "Explorations in Statistics" investigates confidence intervals. A confidence interval is a range that we expect, with some level of confidence, to include the true value of a population parameter…

  20. Interval Recognition in Minimal Context.

    ERIC Educational Resources Information Center

    Shatzkin, Merton

    1984-01-01

    Music majors were asked to identify interval when it was either preceded or followed by a tone moving in the same direction. Difficulties in interval recognition in context appear to be an effect not just of placement within the context or of tonality, but of particular combinations of these aspects. (RM)

  1. Children's Discrimination of Melodic Intervals.

    ERIC Educational Resources Information Center

    Schellenberg, E. Glenn; Trehub, Sandra E.

    1996-01-01

    Adults and children listened to tone sequences and were required to detect changes either from intervals with simple frequency ratios to intervals with complex ratios or vice versa. Adults performed better on changes from simple to complex ratios than on the reverse changes. Similar performance was observed for 6-year olds who had never taken…

  2. Explorations in Statistics: Confidence Intervals

    ERIC Educational Resources Information Center

    Curran-Everett, Douglas

    2009-01-01

    Learning about statistics is a lot like learning about science: the learning is more meaningful if you can actively explore. This third installment of "Explorations in Statistics" investigates confidence intervals. A confidence interval is a range that we expect, with some level of confidence, to include the true value of a population parameter…

  3. Automatic Error Analysis Using Intervals

    ERIC Educational Resources Information Center

    Rothwell, E. J.; Cloud, M. J.

    2012-01-01

    A technique for automatic error analysis using interval mathematics is introduced. A comparison to standard error propagation methods shows that in cases involving complicated formulas, the interval approach gives comparable error estimates with much less effort. Several examples are considered, and numerical errors are computed using the INTLAB…

  4. Automatic Error Analysis Using Intervals

    ERIC Educational Resources Information Center

    Rothwell, E. J.; Cloud, M. J.

    2012-01-01

    A technique for automatic error analysis using interval mathematics is introduced. A comparison to standard error propagation methods shows that in cases involving complicated formulas, the interval approach gives comparable error estimates with much less effort. Several examples are considered, and numerical errors are computed using the INTLAB…

  5. Binary Interval Search: a scalable algorithm for counting interval intersections

    PubMed Central

    Layer, Ryan M.; Skadron, Kevin; Robins, Gabriel; Hall, Ira M.; Quinlan, Aaron R.

    2013-01-01

    Motivation: The comparison of diverse genomic datasets is fundamental to understand genome biology. Researchers must explore many large datasets of genome intervals (e.g. genes, sequence alignments) to place their experimental results in a broader context and to make new discoveries. Relationships between genomic datasets are typically measured by identifying intervals that intersect, that is, they overlap and thus share a common genome interval. Given the continued advances in DNA sequencing technologies, efficient methods for measuring statistically significant relationships between many sets of genomic features are crucial for future discovery. Results: We introduce the Binary Interval Search (BITS) algorithm, a novel and scalable approach to interval set intersection. We demonstrate that BITS outperforms existing methods at counting interval intersections. Moreover, we show that BITS is intrinsically suited to parallel computing architectures, such as graphics processing units by illustrating its utility for efficient Monte Carlo simulations measuring the significance of relationships between sets of genomic intervals. Availability: https://github.com/arq5x/bits. Contact: arq5x@virginia.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:23129298

  6. B7-H1 shapes T-cell–mediated brain endothelial cell dysfunction and regional encephalitogenicity in spontaneous CNS autoimmunity

    PubMed Central

    Klotz, Luisa; Kuzmanov, Ivan; Hucke, Stephanie; Gross, Catharina C.; Posevitz, Vilmos; Dreykluft, Angela; Schulte-Mecklenbeck, Andreas; Janoschka, Claudia; Lindner, Maren; Herold, Martin; Schwab, Nicholas; Ludwig-Portugall, Isis; Kurts, Christian; Meuth, Sven G.; Kuhlmann, Tanja; Wiendl, Heinz

    2016-01-01

    Molecular mechanisms that determine lesion localization or phenotype variation in multiple sclerosis are mostly unidentified. Although transmigration of activated encephalitogenic T cells across the blood–brain barrier (BBB) is a crucial step in the disease pathogenesis of CNS autoimmunity, the consequences on brain endothelial barrier integrity upon interaction with such T cells and subsequent lesion formation and distribution are largely unknown. We made use of a transgenic spontaneous mouse model of CNS autoimmunity characterized by inflammatory demyelinating lesions confined to optic nerves and spinal cord (OSE mice). Genetic ablation of a single immune-regulatory molecule in this model [i.e., B7-homolog 1 (B7-H1, PD-L1)] not only significantly increased incidence of spontaneous CNS autoimmunity and aggravated disease course, especially in the later stages of disease, but also importantly resulted in encephalitogenic T-cell infiltration and lesion formation in normally unaffected brain regions, such as the cerebrum and cerebellum. Interestingly, B7-H1 ablation on myelin oligodendrocyte glycoprotein-specific CD4+ T cells, but not on antigen-presenting cells, amplified T-cell effector functions, such as IFN-γ and granzyme B production. Therefore, these T cells were rendered more capable of eliciting cell contact-dependent brain endothelial cell dysfunction and increased barrier permeability in an in vitro model of the BBB. Our findings suggest that a single immune-regulatory molecule on T cells can be ultimately responsible for localized BBB breakdown, and thus substantial changes in lesion topography in the context of CNS autoimmunity. PMID:27671636

  7. VARIABLE TIME-INTERVAL GENERATOR

    DOEpatents

    Gross, J.E.

    1959-10-31

    This patent relates to a pulse generator and more particularly to a time interval generator wherein the time interval between pulses is precisely determined. The variable time generator comprises two oscillators with one having a variable frequency output and the other a fixed frequency output. A frequency divider is connected to the variable oscillator for dividing its frequency by a selected factor and a counter is used for counting the periods of the fixed oscillator occurring during a cycle of the divided frequency of the variable oscillator. This defines the period of the variable oscillator in terms of that of the fixed oscillator. A circuit is provided for selecting as a time interval a predetermined number of periods of the variable oscillator. The output of the generator consists of a first pulse produced by a trigger circuit at the start of the time interval and a second pulse marking the end of the time interval produced by the same trigger circuit.

  8. Enhanced CD8 T-cell anti-viral function and clinical disease in B7-H1-deficient mice requires CD4 T cells during encephalomyelitis.

    PubMed

    Phares, Timothy W; Stohlman, Stephen A; Hinton, David R; Bergmann, Cornelia C

    2012-12-14

    Anti-viral CD8 T-cell activity is enhanced and prolonged by CD4 T-cell-mediated help, but negatively regulated by inhibitory B7-H1 interactions. During viral encephalomyelitis, the absence of CD4 T cells decreases CD8 T cell activity and impedes viral control in the central nervous system (CNS). By contrast, the absence of B7-H1 enhances CD8 T-cell function and accelerates viral control, but increases morbidity. However, the relative contribution of CD4 T cells to CD8 function in the CNS, in the absence of B7-H1, remains unclear. Wild-type (WT) and B7-H1-/- mice were infected with a gliatropic coronavirus and CD4 T cells depleted to specifically block T helper function in the CNS. Flow cytometry and gene expression analysis of purified T-cell populations from lymph nodes and the CNS was used to directly monitor ex vivo T-cell effector function. The biological affects of altered T-cell responses were evaluated by analysis of viral control and spinal-cord pathology. Increased anti-viral activity by CD8 T cells in the CNS of B7-H1-/- mice was lost upon depletion of CD4 T cells; however, despite concomitant loss of viral control, the clinical disease was less severe. CD4 depletion in B7-H1-/- mice also decreased inducible nitric oxide synthase expression by microglia and macrophages, consistent with decreased microglia/macrophage activation and reduced interferon (IFN)-γ. Enhanced production of IFN-γ, interleukin (IL)-10 and IL-21 mRNA was seen in CD4 T cells from infected B7-H1-/- compared with WT mice, suggesting that over-activated CD4 T cells primarily contribute to the increased pathology. The local requirement of CD4 T-cell help for CD8 T-cell function is not overcome if B7-H1 inhibitory signals are lost. Moreover, the increased effector activity by CD8 T cells in the CNS of B7-H1-/- mice is attributable not only to the absence of B7-H1 upregulation on major histocompatibility complex class I-presenting resident target cells, but also to enhanced local CD4 T

  9. Enhanced CD8 T-cell anti-viral function and clinical disease in B7-H1-deficient mice requires CD4 T cells during encephalomyelitis

    PubMed Central

    2012-01-01

    Background Anti-viral CD8 T-cell activity is enhanced and prolonged by CD4 T-cell-mediated help, but negatively regulated by inhibitory B7-H1 interactions. During viral encephalomyelitis, the absence of CD4 T cells decreases CD8 T cell activity and impedes viral control in the central nervous system (CNS). By contrast, the absence of B7-H1 enhances CD8 T-cell function and accelerates viral control, but increases morbidity. However, the relative contribution of CD4 T cells to CD8 function in the CNS, in the absence of B7-H1, remains unclear. Methods Wild-type (WT) and B7-H1−/− mice were infected with a gliatropic coronavirus and CD4 T cells depleted to specifically block T helper function in the CNS. Flow cytometry and gene expression analysis of purified T-cell populations from lymph nodes and the CNS was used to directly monitor ex vivo T-cell effector function. The biological affects of altered T-cell responses were evaluated by analysis of viral control and spinal-cord pathology. Results Increased anti-viral activity by CD8 T cells in the CNS of B7-H1−/− mice was lost upon depletion of CD4 T cells; however, despite concomitant loss of viral control, the clinical disease was less severe. CD4 depletion in B7-H1−/− mice also decreased inducible nitric oxide synthase expression by microglia and macrophages, consistent with decreased microglia/macrophage activation and reduced interferon (IFN)-γ. Enhanced production of IFN-γ, interleukin (IL)-10 and IL-21 mRNA was seen in CD4 T cells from infected B7-H1−/− compared with WT mice, suggesting that over-activated CD4 T cells primarily contribute to the increased pathology. Conclusions The local requirement of CD4 T-cell help for CD8 T-cell function is not overcome if B7-H1 inhibitory signals are lost. Moreover, the increased effector activity by CD8 T cells in the CNS of B7-H1−/− mice is attributable not only to the absence of B7-H1 upregulation on major histocompatibility complex class I

  10. Chemically activated reactions on the C7H5 energy surface: propargyl + diacetylene, i-C5H3 + acetylene, and n-C5H3 + acetylene.

    PubMed

    da Silva, Gabriel; Trevitt, Adam J

    2011-05-21

    This study uses computational chemistry and statistical reaction rate theory to investigate the chemically activated reaction of diacetylene (butadiyne, C(4)H(2)) with the propargyl radical (C˙H(2)CCH) and the reaction of acetylene (C(2)H(2)) with the i-C(5)H(3) (CH(2)CCCC˙H) and n-C(5)H(3) (CHCC˙HCCH) radicals. A detailed G3SX-level C(7)H(5) energy surface demonstrates that the C(3)H(3) + C(4)H(2) and C(5)H(3) + C(2)H(2) addition reactions proceed with moderate barriers, on the order of 10 to 15 kcal mol(-1), and form activated open-chain C(7)H(5) species that can isomerize to the fulvenallenyl radical with the highest barrier still significantly below the entrance channel energy. Higher-energy pathways are available leading to other C(7)H(5) isomers and to a number of C(7)H(4) species + H. Rate constants in the large multiple-well (15) multiple-channel (30) chemically activated system are obtained from a stochastic solution of the one-dimensional master equation, with RRKM theory for microcanonical rate constants. The dominant products of the C(4)H(2) + C(3)H(3) reaction at combustion-relevant temperatures and pressures are i-C(5)H(3) + C(2)H(2) and CH(2)CCHCCCCH + H, along with several quenched C(7)H(5) intermediate species below 1500 K. The major products in the n-C(5)H(3) + C(2)H(2) reaction are i-C(5)H(3) + C(2)H(2) and a number of C(7)H(4) species + H, with C(7)H(5) radical stabilization at lower temperatures. The i-C(5)H(3) + C(2)H(2) reaction predominantly leads to C(7)H(4) + H and to stabilized C(7)H(5) products. The title reactions may play an important role in polycyclic aromatic hydrocarbon (PAH) formation in combustion systems. The C(7)H(5) potential energy surface developed here also provides insight into several other important reacting gas-phase systems relevant to combustion and astrochemistry, including C(2)H + the C(3)H(4) isomers propyne and allene, benzyne + CH, benzene + C((3)P), and C(7)H(5) radical decomposition, for which some

  11. Comparison of the Lowenstein-Jensen Medium, the Middlebrook 7H10 Medium and MB/BacT for the Isolation of Mycobacterium Tuberculosis (MTB) from Clinical Specimens.

    PubMed

    Naveen, G; Peerapur, Basavaraj V

    2012-12-01

    Tuberculosis (TB) is the most common cause of death due to a single infectious agent worldwide in adults. India alone accounts for 30% of the global tuberculosis burden. There is a need for a method of cultivation of mycobacteria that is reliable and economical and has a short turnaround time. The present study was attempted to assess the feasibility of using MB BACT and Middlebrook 7h10(MB7H10) as primary isolation media for mycobacteria. They were compared with the LJ medium, which was the gold standard. Various clinical specimens from a total of 236 clinically suspected cases of TB were studied. All the samples were decontaminated by using the modified Petroff's method. Each sample was subjected to ZN staining and it was simultaneously inoculated onto the LJ medium, the MB7H10 medium and MB BACT. The growth from the cultures were confirmed by ZN staining and they were speciated by using biochemical reactions. Out of the 236 samples which were screened, 116 isolates were obtained. All the 116 were isolated from MB BACT, 82 were isolated from the LJ medium and 62 were isolated from MB7H10. 82 isolates were obtained from MB BACT and the LJ medium, 62 were obtained from MB7H10 and MB BACT, 58 were isolated from LJ and MB7H10 and 58 were isolated from LJ medium, MB7H10 and MB bact. Neither the L J medium nor the Middlebrook 7h 10 medium could isolate mycobacteria exclusively. It showed that the combination of media did not prove to be superior over the use of MB BACT alone. The average isolation time of L J, the MB7H10 medium and MB BACT was 30.81 days, 31.06 days and 18.70 days. MB BACT is a better medium as compared to the L J medium and the MB7H10 medium, both in terms of the number of isolates and the isolation rate. The MB BACT method proved to be a very speedy method and it could isolate mycobacteria 7-10 days earlier as compared to the L J medium and the Middlebrook 7 H10 medium.

  12. B7-H3 and B7x are highly expressed in human prostate cancer and associated with disease spread and poor outcome

    PubMed Central

    Zang, Xingxing; Thompson, R. Houston; Al-Ahmadie, Hikmat A.; Serio, Angel M.; Reuter, Victor E.; Eastham, James A.; Scardino, Peter T.; Sharma, Padmanee; Allison, James P.

    2007-01-01

    B7-H3 and B7x are recently discovered members of the B7-CD28 family thought to dampen peripheral immune responses via negative costimulation. We evaluated their potential expression in human prostate cancer using a large cohort of patients with 7 years of follow-up. We identified 823 patients with tissue available treated with radical prostatectomy between 1985 and 2003. Immunohistochemistry was performed on tissue microarray sections using anti-B7-H3 and -B7x. The percentage and intensity of immunoreactivity by tumor cells were blindly evaluated by two urological pathologists, and outcome analyses were conducted. Both B7-H3 and B7x were highly expressed; 93% and 99% of tumors had aberrant expression, respectively. The median percentage of tumor cells staining positive was 80% for each molecule. Strong intensity for B7-H3 and B7x was noted in 212 (26%) and 120 (15%) patients, respectively. Patients with strong intensity for B7-H3 and B7x were significantly more likely to have disease spread at time of surgery (P < 0.001 and P = 0.005, respectively). Additionally, patients with strong intensity for B7-H3 and B7x were at significantly increased risk of clinical cancer recurrence (P < 0.001 and P = 0.005) and cancer-specific death (P = 0.004 and P = 0.04, respectively). To our knowledge, we present the largest investigation of B7 family molecules in a human malignancy and a previously undescribed evaluation of B7x in prostate cancer. B7-H3 and B7x are abundantly expressed in prostate cancer and associated with disease spread and poor outcome. Given the proposed immune-inhibitory mechanisms of B7-H3 and B7x, these molecules represent attractive targets for therapeutic manipulation in prostate cancer. PMID:18042703

  13. CagA-dependent downregulation of B7-H2 expression on gastric mucosa and inhibition of Th17 responses during Helicobacter pylori infection

    PubMed Central

    Lina, Taslima T.; Pinchuk, Irina V.; House, Jennifer; Yamaoka, Yoshio; Graham, David Y.; Beswick, Ellen J.; Reyes, Victor E.

    2013-01-01

    Gastric epithelial cells (GECs) are the primary target for Helicobacter pylori (H. pylori) infection and may act as antigen presenting cells (APC) regulating local T cell responses. We previously reported that H. pylori infection of GECs induces the expression of the T cell co-inhibitory molecule B7-H1 on GECs. This process contributes to the hyporesponsiveness of CD4+ effector T cells and accumulation of T regulatory cells. In the studies presented herein we investigated the impact of H. pylori cytotoxin CagA on the modulation of the expression of the T cell co-stimulator B7-H2 by GEC. B7-H2 is involved in promoting Th17 type responses. H. pylori infection downregulates B7-H2 expression by GECs in a CagA dependent manner. IFNγ, which is increased in the H. pylori infected gastric mucosa, synergizes with H. pylori in downregulating B7-H2 expression by GECs. CagA-mediated modulation of B7-H2 on GEC involves p70 S6 kinase phosphorylation. The CagA-dependent B7-H2 downregulation in GEC correlates with a decrease in Th17 type responses in vitro and in vivo. Further, CagA-dependent modulation of Th17 responses inversely correlated with the H. pylori colonization levels in vivo. Our data suggest that CagA contributes to the ability of H. pylori to evade Th17 mediated clearance by modulating expression of B7-H2 and, thus, to the establishment of the H. pylori chronic infection. PMID:23997227

  14. B7-H4Ig inhibits mouse and human T-cell function and treats EAE via IL-10/Treg-dependent mechanisms.

    PubMed

    Podojil, Joseph R; Liu, Linda N; Marshall, Shannon A; Chiang, Ming-Yi; Goings, Gwen E; Chen, Lieping; Langermann, Solomon; Miller, Stephen D

    2013-08-01

    We evaluated the therapeutic efficacy and mechanisms of action of both mouse and human B7-H4 Immunoglobulin fusion proteins (mB7-H4Ig; hB7-H4Ig) in treating EAE. The present data show that mB7-H4Ig both directly and indirectly (via increasing Treg function) inhibited CD4⁺ T-cell proliferation and differentiation in both Th1- and Th17-cell promoting conditions while inducing production of IL-10. B7-H4Ig treatment effectively ameliorated progression of both relapsing (R-EAE) and chronic EAE correlating with decreased numbers of activated CD4⁺ T-cells within the CNS and spleen, and a concurrent increase in number and function of Tregs. The functional requirement for Treg activation in treating EAE was demonstrated by a loss of therapeutic efficacy of hB7-H4Ig in R-EAE following inactivation of Treg function either by anti-CD25 treatment or blockade of IL-10. Significant to the eventual translation of this treatment into clinical practice, hB7-H4Ig similarly inhibited the in vitro differentiation of naïve human CD4⁺ T-cells in both Th1- and Th17-promoting conditions, while promoting the production of IL-10. B7-H4Ig thus regulates pro-inflammatory T-cell responses by a unique dual mechanism of action and demonstrates significant promise as a therapeutic for autoimmune diseases, including MS. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. B7-H3 Augments Inflammatory Responses and Exacerbates Brain Damage via Amplifying NF-κB p65 and MAPK p38 Activation during Experimental Pneumococcal Meningitis

    PubMed Central

    Chen, Xuqin; Li, Yan; Blankson, Siobhan; Liu, Min; Huang, Danping; Redmond, H. Paul; Huang, Jing; Wang, Jiang Huai; Wang, Jian

    2017-01-01

    The costimulatory protein B7-H3 has been shown to play a contributory role in the development and progression of experimental pneumococcal meningitis by augmentation of the innate immunity-associated inflammatory response via a TLR2-dependent manner. This study aimed to clarify the component(s) of TLR2-mediated signal transduction pathways responsible for B7-H3-augmented inflammatory response and subsequent brain damage during experimental pneumococcal meningitis. Administration of B7-H3 did not augment expression of TLR2 and other TLR2 upstream components, but led to an enhanced formation of MyD88-IRAK immunocomplex in the brain of S. pneumoniae-infected mice. Furthermore, B7-H3 substantially augmented S. pneumoniae-induced activation of TLR2 downstream NF-κB p65 and MAPK p38 pathways in the brain of S. pneumoniae-infected mice. Notably, blockage of NF-κB p65 and/or MAPK p38 with their specific inhibitors strongly attenuated B7-H3-amplified inflammatory response with significantly reduced proinflammatory cytokine and chemokine production, and markedly ameliorated B7-H3-exacerbated disruption of blood-brain barrier and severity of disease status in S. pneumoniae-infected mice. These results indicate that targeting NF-κB p65 and/or MAPK p38 may represent a promising therapeutic option for amelioration of overwhelming inflammatory response-associated brain injury frequently observed during pneumococcal meningitis. PMID:28141831

  16. Metalloprotease-mediated tumor cell shedding of B7-H6, the ligand of the natural killer cell-activating receptor NKp30.

    PubMed

    Schlecker, Eva; Fiegler, Nathalie; Arnold, Annette; Altevogt, Peter; Rose-John, Stefan; Moldenhauer, Gerhard; Sucker, Antje; Paschen, Annette; von Strandmann, Elke Pogge; Textor, Sonja; Cerwenka, Adelheid

    2014-07-01

    Natural killer (NK) cells are potent immune effector cells capable of mediating antitumor responses. Thus, during immunoediting, tumor cell populations evolve strategies to escape NK-cell-mediated recognition. In this study, we report a novel mechanism of immune escape involving tumor cell shedding of B7-H6, a ligand for the activating receptor NKp30 that mediates NK-cell binding and NK-cell-mediated killing. Tumor cells from different cancer entities released B7-H6 by ectodomain shedding mediated by the cell surface proteases "a disintegrin and metalloproteases" (ADAM)-10 and ADAM-17, as demonstrated through the use of pharmacologic inhibitors or siRNA-mediated gene attenuation. Inhibiting this proteolytic shedding process increased the levels of B7-H6 expressed on the surface of tumor cells, enhancing NKp30-mediated activation of NK cells. Notably, we documented elevated levels of soluble B7-H6 levels in blood sera obtained from a subset of patients with malignant melanoma, compared with healthy control individuals, along with evidence of elevated B7-H6 expression in melanoma specimens in situ. Taken together, our results illustrated a novel mechanism of immune escape in which tumor cells impede NK-mediated recognition by metalloprotease-mediated shedding of B7-H6. One implication of our findings is that therapeutic inhibition of specific metalloproteases may help support NK-cell-based cancer therapy.

  17. The PD-1/B7-H1 Pathway Modulates the Natural Killer Cells versus Mouse Glioma Stem Cells

    PubMed Central

    Zong, Wen Jing; Yu, Chun Jiang; Li, Jun Fa; Qu, Yan Ming; Han, Song

    2015-01-01

    Purpose Glioblastoma multiforme (GBM) is the most malignant primary type of brain tumor in adults. There has been increased focus on the immunotherapies to treat GBM patients, the therapeutic value of natural killer (NK) cells is still unknown. Programmed death-1 (PD-1) is a major immunological checkpoint that can negatively regulate the T-cell-mediated immune response. We tested the combination of the inhibiting the PD-1/B7H1 pathway with a NK-cell mediated immune response in an orthotopic mouse model of GBM. Methods and Materials Mouse glioma stem cells (GL261GSCs) and mouse NK cells were isolated and identified. A lactate dehydrogenase (LDH) assay was perfomed to detect the cytotoxicity of NK cells against GL261GSCs. GL261GSCs were intracranially implanted into mice, and the mice were stratified into 3 treatment groups: 1) control, 2) NK cells treatment, and 3) PD-1 inhibited NK cells treatment group. Overall survival was quantified, and animal magnetic resonance imaging (MRI) was performed to determine tumor growth. The brains were harvested after the mice were euthanized, and immunohistochemistry against CD45 and PCNA was performed. Results The mouse NK cells were identified as 90% CD3- NK1.1+CD335+ by flow cytometric analysis. In the LDH assay, the ratios of the damaged GL261GSCs, with the E:T ratios of 2.5:1, 5:1, and 10:1, were as follows: 1) non-inhibited group: 7.42%, 11.31%, and 15.1%, 2) B7H1 inhibited group: 14.75%, 18.25% and 29.1%, 3) PD-1 inhibited group: 15.53%, 19.21% and 29.93%, 4) double inhibited group: 33.24%, 42.86% and 54.91%. In the in vivo experiments, the mice in the PD-1 inhibited NK cells treatment group and IL-2-stimulated-NK cells treatment group displayed a slowest tumor growth (F = 308.5, P<0.01) and a slower tumor growth compared with control group (F = 118.9, P<0.01), respectively. The median survival of the mice in the three groups were as follows: 1) conrol group: 29 days, 2) NK cells treatment group: 35 days (P = 0.0012), 3) PD

  18. TIME-INTERVAL MEASURING DEVICE

    DOEpatents

    Gross, J.E.

    1958-04-15

    An electronic device for measuring the time interval between two control pulses is presented. The device incorporates part of a previous approach for time measurement, in that pulses from a constant-frequency oscillator are counted during the interval between the control pulses. To reduce the possible error in counting caused by the operation of the counter gating circuit at various points in the pulse cycle, the described device provides means for successively delaying the pulses for a fraction of the pulse period so that a final delay of one period is obtained and means for counting the pulses before and after each stage of delay during the time interval whereby a plurality of totals is obtained which may be averaged and multplied by the pulse period to obtain an accurate time- Interval measurement.

  19. Simple Interval Timers for Microcomputers.

    ERIC Educational Resources Information Center

    McInerney, M.; Burgess, G.

    1985-01-01

    Discusses simple interval timers for microcomputers, including (1) the Jiffy clock; (2) CPU count timers; (3) screen count timers; (4) light pen timers; and (5) chip timers. Also examines some of the general characteristics of all types of timers. (JN)

  20. B7-H1–expressing antigen-presenting cells mediate polarization of protumorigenic Th22 subsets

    PubMed Central

    Kuang, Dong-Ming; Xiao, Xiao; Zhao, Qiyi; Chen, Min-Min; Li, Xue-Feng; Liu, Rui-Xian; Wei, Yuan; Ouyang, Fang-Zhu; Chen, Dong-Ping; Wu, Yan; Lao, Xiang-Ming; Deng, Hong; Zheng, Limin

    2014-01-01

    Classical IL-22–producing T helper cells (Th22 cells) mediate inflammatory responses independently of IFN-γ and IL-17; however, nonclassical Th22 cells have been recently identified and coexpress IFN-γ and/or IL-17 along with IL-22. Little is known about how classical and nonclassical Th22 subsets in human diseases are regulated. Here, we used samples of human blood, normal and peritumoral liver, and hepatocellular carcinoma (HCC) to delineate the phenotype, distribution, generation, and functional relevance of various Th22 subsets. Three nonclassical Th22 subsets constituted the majority of all Th22 cells in human liver and HCC tissues, although the classical Th22 subset was predominant in blood. Monocytes activated by TLR2 and TLR4 agonists served as the antigen-presenting cells (APCs) that most efficiently triggered the expansion of nonclassical Th22 subsets from memory T cells and classical Th22 subsets from naive T cells. Moreover, B7-H1–expressing monocytes skewed Th22 polarization away from IFN-γ and toward IL-17 through interaction with programmed death 1 (PD-1), an effect that can create favorable conditions for in vivo aggressive cancer growth and angiogenesis. Our results provide insight into the selective modulation of Th22 subsets and suggest that strategies to influence functional activities of inflammatory cells may benefit anticancer therapy. PMID:25244097

  1. Raman Spectroscopy of a-C:H Films Deposited Using Ar + H2 + C7H8 Plasma CVD

    NASA Astrophysics Data System (ADS)

    Dong, Xiao; Koga, Kazunori; Yamashita, Daisuke; Seo, Hyunwoong; Itagaki, Naho; Shiratani, Masaharu; Setsuhara, Yuichi; Sekine, Makoto; Hori, Masaru

    2015-09-01

    We investigated the effects of ion energy on Raman spectra of a-C:H films prepared by Ar + H2 + C7H8 plasma CVD. Raman spectra were measured with a laser Raman spectrometer (JASCO NRS-3100). Both the D-peak position and G-peak position shift toward higher wavenumbers as ion energy increases. The intensity ratio of the D-peak and G-peak, ID/IG increases with increasing the ion energy, indicating that the amount of ring-like sp2 clusters increases. The H content in a-C:H derived from photoluminescence (PL) background decreases with increasing the ion energy. The full width at half maximum of the G-peak, FWHMG related to the C-C sp3 content and H content increases with increasing the ion energy to 100 eV, whereas it decreases with increasing further the ion energy to 105 eV. The variation of FWHMG is consistent with that of mass density. There results indicate that the structure of a-C:H films transforms from polymer-like carbon to diamond-like one with increasing the ion energy above the threshold value of ~ 100 eV.

  2. Tumour-derived PGD2 and NKp30-B7H6 engagement drives an immunosuppressive ILC2-MDSC axis.

    PubMed

    Trabanelli, Sara; Chevalier, Mathieu F; Martinez-Usatorre, Amaia; Gomez-Cadena, Alejandra; Salomé, Bérengère; Lecciso, Mariangela; Salvestrini, Valentina; Verdeil, Grégory; Racle, Julien; Papayannidis, Cristina; Morita, Hideaki; Pizzitola, Irene; Grandclément, Camille; Bohner, Perrine; Bruni, Elena; Girotra, Mukul; Pallavi, Rani; Falvo, Paolo; Leibundgut, Elisabeth Oppliger; Baerlocher, Gabriela M; Carlo-Stella, Carmelo; Taurino, Daniela; Santoro, Armando; Spinelli, Orietta; Rambaldi, Alessandro; Giarin, Emanuela; Basso, Giuseppe; Tresoldi, Cristina; Ciceri, Fabio; Gfeller, David; Akdis, Cezmi A; Mazzarella, Luca; Minucci, Saverio; Pelicci, Pier Giuseppe; Marcenaro, Emanuela; McKenzie, Andrew N J; Vanhecke, Dominique; Coukos, George; Mavilio, Domenico; Curti, Antonio; Derré, Laurent; Jandus, Camilla

    2017-09-19

    Group 2 innate lymphoid cells (ILC2s) are involved in human diseases, such as allergy, atopic dermatitis and nasal polyposis, but their function in human cancer remains unclear. Here we show that, in acute promyelocytic leukaemia (APL), ILC2s are increased and hyper-activated through the interaction of CRTH2 and NKp30 with elevated tumour-derived PGD2 and B7H6, respectively. ILC2s, in turn, activate monocytic myeloid-derived suppressor cells (M-MDSCs) via IL-13 secretion. Upon treating APL with all-trans retinoic acid and achieving complete remission, the levels of PGD2, NKp30, ILC2s, IL-13 and M-MDSCs are restored. Similarly, disruption of this tumour immunosuppressive axis by specifically blocking PGD2, IL-13 and NKp30 partially restores ILC2 and M-MDSC levels and results in increased survival. Thus, using APL as a model, we uncover a tolerogenic pathway that may represent a relevant immunosuppressive, therapeutic targetable, mechanism operating in various human tumour types, as supported by our observations in prostate cancer.Group 2 innate lymphoid cells (ILC2s) modulate inflammatory and allergic responses, but their function in cancer immunity is still unclear. Here the authors show that, in acute promyelocytic leukaemia, tumour-activated ILC2s secrete IL-13 to induce myeloid-derived suppressor cells and support tumour growth.

  3. B7-H1-Deficiency Enhances the Potential of Tolerogenic Dendritic Cells by Activating CD1d-Restricted Type II NKT Cells

    PubMed Central

    Brandl, Carolin; Ortler, Sonja; Herrmann, Thomas; Cardell, Susanna; Lutz, Manfred B.; Wiendl, Heinz

    2010-01-01

    Background Dendritic cells (DC) can act tolerogenic at a semi-mature stage by induction of protective CD4+ T cell and NKT cell responses. Methodology/Principal Findings Here we studied the role of the co-inhibitory molecule B7-H1 (PD-L1, CD274) on semi-mature DC that were generated from bone marrow (BM) cells of B7-H1−/− mice and applied to the model of Experimental Autoimmune Encephalomyelitis (EAE). Injections of B7-H1-deficient DC showed increased EAE protection as compared to wild type (WT)-DC. Injections of B7-H1−/− TNF-DC induced higher release of peptide-specific IL-10 and IL-13 after restimulation in vitro together with elevated serum cytokines IL-4 and IL-13 produced by NKT cells, and reduced IL-17 and IFN-γ production in the CNS. Experiments in CD1d−/− and Jα281−/− mice as well as with type I and II NKT cell lines indicated that only type II NKT cells but not type I NKT cells (invariant NKT cells) could be stimulated by an endogenous CD1d-ligand on DC and were responsible for the increased serum cytokine production in the absence of B7-H1. Conclusions/Significance Together, our data indicate that BM-DC express an endogenous CD1d ligand and B7-H1 to ihibit type II but not type I NKT cells. In the absence of B7-H1 on these DC their tolerogenic potential to stimulate tolerogenic CD4+ and NKT cell responses is enhanced. PMID:20520738

  4. Structural Insights into the Inhibitory Mechanism of an Antibody against B7-H6, a Stress-Induced Cellular Ligand for the Natural Killer Cell Receptor NKp30.

    PubMed

    Xu, Xiaoping; Narni-Mancinelli, Emilie; Cantoni, Claudia; Li, Yili; Guia, Sophie; Gauthier, Laurent; Chen, Qianming; Moretta, Alessandro; Vély, Frédéric; Eisenstein, Edward; Rangarajan, Sneha; Vivier, Eric; Mariuzza, Roy A

    2016-11-06

    Antibodies have been shown to block signaling through cell surface receptors using several mechanisms. The two most common are binding to the ligand-binding site of the receptor and, conversely, binding to the receptor-binding site of the ligand. Here, we investigated the inhibitory mechanism of an antibody (17B1.3) against human B7-H6, a stress-induced cellular ligand for the natural killer (NK) cell receptor NKp30. Binding of this antibody to B7-H6, a transmembrane protein expressed on tumor and other stressed cells, but not on normal cells, prevents NK cell activation via NKp30. We determined the crystal structure of antibody 17B1.3 in complex with the ectodomain of B7-H6 to 2.5Å resolution. Surprisingly, 17B1.3 binds to a site on B7-H6 that is completely distinct from the binding site for NKp30, such that 17B1.3 does not block the NKp30-B7-H6 interaction. We then asked whether 17B1.3 prevents signaling by binding to a putative site for B7-H6 dimerization. However, structure-based mutations designed to disrupt potential B7-H6 dimerization through this site did not diminish NKp30-mediated cell activation. We conclude that the bulky 17B1.3 antibody most likely acts by sterically interfering with close cell-cell contacts at the NK cell-target cell interface that are required for NK cell activation. A similar inhibitory mechanism may apply to other antibodies, including therapeutic antibodies that block signaling through cell surface receptors whose ligands are also cell surface proteins.

  5. PI3K-delta mediates double-stranded RNA-induced upregulation of B7-H1 in BEAS-2B airway epithelial cells

    SciTech Connect

    Kan-o, Keiko; Matsumoto, Koichiro; Asai-Tajiri, Yukari; Fukuyama, Satoru; Hamano, Saaka; Seki, Nanae; Nakanishi, Yoichi; Inoue, Hiromasa

    2013-05-31

    Highlights: •Double-stranded RNA upregulates B7-H1 on BEAS-2B airway epithelial cells. •The upregulation of B7-H1 is attenuated by inhibition of PI3Kδ isoform. •PI3Kδ-mediated upregulation of B7-H1 is independent of NF-κB activation. •Inhibition of PI3Kδ may prevent persistent viral infection induced by B7-H1. -- Abstract: Airway viral infection disturbs the health-related quality of life. B7-H1 (also known as PD-L1) is a coinhibitory molecule associated with the escape of viruses from the mucosal immunity, leading to persistent infection. Most respiratory viruses generate double-stranded (ds) RNA during replication. The stimulation of cultured airway epithelial cells with an analog of viral dsRNA, polyinosinic-polycytidylic acid (poly IC) upregulates the expression of B7-H1 via activation of the nuclear factor κB(NF-κB). The mechanism of upregulation was investigated in association with phosphatidylinositol 3-kinases (PI3Ks). Poly IC-induced upregulation of B7-H1 was profoundly suppressed by a pan-PI3K inhibitor and partially by an inhibitor or a small interfering (si)RNA for PI3Kδ in BEAS-2B cells. Similar results were observed in the respiratory syncytial virus-infected cells. The expression of p110δ was detected by Western blot and suppressed by pretreatment with PI3Kδ siRNA. The activation of PI3Kδ is typically induced by oxidative stress. The generation of reactive oxygen species was increased by poly IC. Poly IC-induced upregulation of B7-H1 was attenuated by N-acetyl-L-cysteine, an antioxidant, or by oxypurinol, an inhibitor of xanthine oxidase. Poly IC-induced activation of NF-κB was suppressed by a pan-PI3K inhibitor but not by a PI3Kδ inhibitor. These results suggest that PI3Kδ mediates dsRNA-induced upregulation of B7-H1 without affecting the activation of NF-κB.

  6. High resolution time interval meter

    DOEpatents

    Martin, A.D.

    1986-05-09

    Method and apparatus are provided for measuring the time interval between two events to a higher resolution than reliability available from conventional circuits and component. An internal clock pulse is provided at a frequency compatible with conventional component operating frequencies for reliable operation. Lumped constant delay circuits are provided for generating outputs at delay intervals corresponding to the desired high resolution. An initiation START pulse is input to generate first high resolution data. A termination STOP pulse is input to generate second high resolution data. Internal counters count at the low frequency internal clock pulse rate between the START and STOP pulses. The first and second high resolution data are logically combined to directly provide high resolution data to one counter and correct the count in the low resolution counter to obtain a high resolution time interval measurement.

  7. Finding Nested Common Intervals Efficiently

    NASA Astrophysics Data System (ADS)

    Blin, Guillaume; Stoye, Jens

    In this paper, we study the problem of efficiently finding gene clusters formalized by nested common intervals between two genomes represented either as permutations or as sequences. Considering permutations, we give several algorithms whose running time depends on the size of the actual output rather than the output in the worst case. Indeed, we first provide a straightforward O(n 3) time algorithm for finding all nested common intervals. We reduce this complexity by providing an O(n 2) time algorithm computing an irredundant output. Finally, we show, by providing a third algorithm, that finding only the maximal nested common intervals can be done in linear time. Considering sequences, we provide solutions (modifications of previously defined algorithms and a new algorithm) for different variants of the problem, depending on the treatment one wants to apply to duplicated genes.

  8. Helicobacter Pylori Promote B7-H1 Expression by Suppressing miR-152 and miR-200b in Gastric Cancer Cells

    PubMed Central

    Xie, Gengchen; Li, Wei; Li, Ruidong; Wu, Ke; Zhao, Ende; Zhang, Yu; Zhang, Peng; Shi, Liang; Wang, Di; Yin, Yuping; Deng, Rui; Tao, Kaixiong

    2017-01-01

    The most common cause of gastric cancer is infection with helicobacter pylori (HP), but the associated molecular mechanism is not well understood. In the present study, we found a marked increase in the expression of B7-H1, a member of the B7 co-stimulatory family of molecules that bind to programmed death-1 (PD-1) and play a critical immunoregulatory role in the cell-mediated immune response, in HP-positive gastric cancer tissue. Infection of cultured gastric cancer cells with HP promoted B7-H1 expression and inhibited miR-152 and miR-200b expression. We further demonstrated that these two miRNAs targeted B7-H1 mRNA and suppressed B7-H1 expression in gastric cancer cells. Finally, B7-H1 expression was found to correlate with miR-152 and miR-200b levels in gastric tumor tissues from human patients. Our findings suggest a novel mechanism by which HP infection promotes gastric cancer and also suggest potential targets, i.e., miR-152 and miR-200b, for the prevention and treatment of gastric cancer. PMID:28056089

  9. Low-lying excited states and nonradiative processes of the adenine analogues 7H- and 9H-2-aminopurine.

    PubMed

    Lobsiger, Simon; Sinha, Rajeev K; Trachsel, Maria; Leutwyler, Samuel

    2011-03-21

    We have investigated the UV vibronic spectra and excited-state nonradiative processes of the 7H- and 9H-tautomers of jet-cooled 2-aminopurine (2AP) and of the 9H-2AP-d(4) and -d(5) isotopomers, using two-color resonant two-photon ionization spectroscopy at 0.3 and 0.045  cm(-1) resolution. The S(1) ← S(0) transition of 7H-2AP was observed for the first time. It lies ∼1600  cm(-1) below that of 9H-2AP, is ∼1000 times weaker and exhibits only in-plane vibronic excitations. In contrast, the S(1) ← S(0) spectra of 9H-2AP, 9H-2AP-d(4), and 9H-2AP-d(5) show numerous low-frequency bands that can be systematically assigned to overtone and combinations of the out-of-plane vibrations ν(1)', ν(2)', and ν(3)'. The intensity of these out-of-plane bands reflects an out-of-plane deformation in the (1)ππ∗(L(a)) state. Approximate second-order coupled-cluster theory also predicts that 2-aminopurine undergoes a "butterfly" deformation in its lowest (1)ππ∗ state. The rotational contours of the 9H-2AP, 9H-2AP-d(4), and 9H-2AP-d(5) 0(0)(0) bands and of eight vibronic bands of 9H-2AP up to 0(0)(0) + 600 cm(-1) exhibit 75%-80% in-plane (a∕b) polarization, which is characteristic for a (1)ππ∗ excitation. A 20%-25% c-axis (perpendicular) transition dipole moment component may indicate coupling of the (1)ππ∗ bright state to the close-lying (1)nπ∗ dark state. However, no (1)nπ∗ vibronic bands were detected below or up to 500  cm(-1) above the (1)ππ∗ 0(0)(0) band. Following (1)ππ∗ excitation, 9H-2AP undergoes a rapid nonradiative transition to a lower-lying long-lived state with a lifetime ≥5 μs. The ionization potential of 9H-2AP was measured via the (1)ππ∗ state (IP = 8.020 eV) and the long-lived state (IP > 9.10 eV). The difference shows that the long-lived state lies ≥1.08 eV below the (1)ππ∗ state. Time-dependent B3LYP calculations predict the (3)ππ∗ (T(1)) state 1.12 eV below the (1)ππ∗ state, but place the (1)n

  10. Formation of C3H2, C5H2, C7H2, and C9H2 from reactions of CH, C3H, C5H, and C7H radicals with C2H2.

    PubMed

    Sun, Yi-Lun; Huang, Wen-Jian; Lee, Shih-Huang

    2016-01-21

    The Cm+2H2 family can be classified into two categories - C2n+1H2 and C2n+2H2. Cm+2H2 are important intermediates in the syntheses of large carbonaceous molecules. An understanding of the formation mechanisms of both odd and even carbon-numbered Cm+2H2 is beneficial to atmospheric, astronomical, and combustion chemistry. HC2n+2H (polyynes) are believed to be producible from C2nH + C2H2 and C2H + C2nH2 reactions but C2n+1H2 (n≥ 2) attract less attention to their formation mechanisms. In the present study, we make up for the lack of knowledge on C2n+1H2 formation mechanisms by investigating the reactions C2n-1H + C2H2→ C2n+1H2 + H with n = 1-4. The dynamics of reactions of C2n-1H radicals with C2H2 are explored in crossed molecular beams using products C2n+1H2. The translational-energies and angular distributions of the hydrogen-loss channels of products are unraveled by measuring time-of-flight spectra and photoionization-efficiency spectra of C2n+1H2 with tunable synchrotron vacuum-ultraviolet ionization. The C2n+1H2 product includes two isomers, c-(1)HC2n-1(C)CH and (3)HC2n+1H, which are identified by the maximal translational-energy release and the photoionization threshold. Furthermore, quantum-chemical calculations indicate that the title reactions incur a small or negligible entrance barrier and are nearly isoergic except for the barrierless exothermic reaction CH + C2H2→ C3H2 + H. We demonstrate for the first time that C5H2, C7H2, and C9H2 are producible from the title reactions. In conjunction with studies on the C2nH + C2H2 reactions, a brief picture for the CmH (m = 1-8) + C2H2→ Cm+2H2 + H reactions can be outlined.

  11. The mixed sandwich compounds C5H5MC7H7 of the first row transition metals: variable hapticity of the seven-membered ring

    NASA Astrophysics Data System (ADS)

    Wang, Hongyan; Xie, Yaoming; Silaghi-Dumitrescu, Ioan; Bruce King, R.; Schaefer, Henry F., III

    2010-04-01

    The mixed sandwich compounds (η5-C5H5)M(η7-C7H7) (M = Ti, V, Cr) have been known for approximately 50 years. The vanadium derivative ('trovacene') has recently been shown to be a useful precursor for the preparation of a variety of paramagnetic sandwich compounds. In this connection the structures of the complete series of the first row transition metal mixed sandwich compounds C5H5MC7H7 (M = Ti, V, Cr, Mn, Fe, Co, Ni) have been investigated by density functional theory. The experimentally known parallel ring sandwich structures (η5-C5H5)M(η7-C7H7) are found for the Ti, V, and Cr derivatives. Analysis of the frontier molecular orbitals of these complexes indicates that, for the metal d-orbitals, the z 2 orbital is essentially non-bonding, the x 2-y 2 and xy orbitals are δ bonding to the seven-membered ring, and the xz and yz orbitals are π bonding to the five-membered ring. For the later transition metals, (η5-C5H5)M(η5-C7H7) structures with pentahapto seven-membered rings are preferred for iron and manganese and (η5-C5H5)M(η3-C7H7) structures with trihapto seven-membered rings are preferred for cobalt and nickel, leading to either 17- or 18-electron complexes in all cases. A higher energy parallel sandwich structure (η5-C5H5)Co(η7-C7H7) with a quartet spin state and a formal 21-electron cobalt configuration is also found for the cobalt derivative.

  12. Immune evasion of mantle cell lymphoma: expression of B7-H1 leads to inhibited T-cell response to and killing of tumor cells.

    PubMed

    Wang, Lijuan; Qian, Jianfei; Lu, Yong; Li, Haiyan; Bao, Hanying; He, Donghua; Liu, Zhiqiang; Zheng, Yuhuan; He, Jin; Li, Yi; Neelapu, Sattva; Yang, Jing; Kwak, Larry W; Yi, Qing; Cai, Zhen

    2013-09-01

    Clinical trials of immunotherapy in mantle cell lymphoma have not yet delivered desirable results, partly because of the inhibitory machinery of the tumor and its microenvironment. Here we investigated the role of B7-H1, a member of the B7 family of co-stimulatory/co-inhibitory ligands, in mantle cell lymphoma-mediated immunosuppression. Allogeneic CD3(+), CD4(+) and CD8(+) T cells were purified and co-cultured with irradiated mantle cell lymphoma cells. Mantle cell lymphoma-reactive T-cell lines from HLA-A*0201(+) healthy blood donors were generated after in vitro restimulation, and were subjected to functional tests. We found that B7-H1 expressed on mantle cell lymphoma cells was able to inhibit T-cell proliferation induced by the tumor cells, impair the generation of antigen-specific T-cell responses, and render mantle cell lymphoma cells resistant to T-cell-mediated cytolysis. Blocking or knocking down B7-H1 on mantle cell lymphoma cells enhanced T-cell responses and restored tumor-cell sensitivity to T-cell-mediated killing in vitro and in vivo. Knocking down B7-H1 on mantle cell lymphoma cells primed more CD4(+) or CD8(+) memory effector T cells. Our study demonstrates for the first time that lymphoma cell-expressed B7-H1 may lead to the suppression of host anti-tumor immune responses in mantle cell lymphoma and targeting tumor cell B7-H1 may represent a novel approach to improve the efficacy of immunotherapy in patients with mantle cell lymphoma.

  13. High resolution time interval counter

    NASA Technical Reports Server (NTRS)

    Zhang, Victor S.; Davis, Dick D.; Lombardi, Michael A.

    1995-01-01

    In recent years, we have developed two types of high resolution, multi-channel time interval counters. In the NIST two-way time transfer MODEM application, the counter is designed for operating primarily in the interrupt-driven mode, with 3 start channels and 3 stop channels. The intended start and stop signals are 1 PPS, although other frequencies can also be applied to start and stop the count. The time interval counters used in the NIST Frequency Measurement and Analysis System are implemented with 7 start channels and 7 stop channels. Four of the 7 start channels are devoted to the frequencies of 1 MHz, 5 MHz or 10 MHz, while triggering signals to all other start and stop channels can range from 1 PPS to 100 kHz. Time interval interpolation plays a key role in achieving the high resolution time interval measurements for both counters. With a 10 MHz time base, both counters demonstrate a single-shot resolution of better than 40 ps, and a stability of better than 5 x 10(exp -12) (sigma(sub chi)(tau)) after self test of 1000 seconds). The maximum rate of time interval measurements (with no dead time) is 1.0 kHz for the counter used in the MODEM application and is 2.0 kHz for the counter used in the Frequency Measurement and Analysis System. The counters are implemented as plug-in units for an AT-compatible personal computer. This configuration provides an efficient way of using a computer not only to control and operate the counters, but also to store and process measured data.

  14. Development of DS-5573a: A novel afucosylated mAb directed at B7-H3 with potent antitumor activity.

    PubMed

    Nagase-Zembutsu, Akiko; Hirotani, Kenji; Yamato, Michiko; Yamaguchi, Junko; Takata, Takehiko; Yoshida, Makoto; Fukuchi, Keisuke; Yazawa, Mitsuhiro; Takahashi, Shu; Agatsuma, Toshinori

    2016-05-01

    B7-H3 is highly overexpressed in a variety of human clinical tumors, and its expression is significantly associated with poor outcomes. In our study, we aimed to develop new antitumor mAbs by employing cancer cell immunization, and succeeded in generating a mouse anti-human B7-H3 antibody (M30) that shows antitumor activity. M30 was humanized (Hu-M30), and an afucosylated Hu-M30 (DS-5573a) was also generated. To assess the potency of DS-5573a as a therapeutic mAb, we characterized this mAb and evaluated its antitumor activity in vitro and in vivo. Flow cytometry analysis showed that B7-H3 proteins were expressed on various types of cancer cell lines broadly, and DS-5573a binds to IgC1 and IgC2 domains of human B7-H3. Antibody-dependent cellular cytotoxicity activity of DS-5573a was drastically enhanced against medium to high B7-H3-expressing cancer cell lines MDA-MB-231 and NCI-H322. DS-5573a also induced high antibody-dependent cellular cytotoxicity activity against low B7-H3-expressing cancer cell line COLO205, whereas Hu-M30 induced little activity against it. In addition, DS-5573a was found to be a novel anti-B7-H3 antibody which showed antibody-dependent cellular phagocytosis activity. Furthermore, DS-5573a showed dose-dependent and significant antitumor efficacy (0.03-3 mg/kg) in MDA-MB-231-bearing SCID mice (which have functional natural killer cells and macrophages), but little antitumor efficacy in NOG mice (which lack natural killer cells and have reduced macrophage function). These results suggest that antitumor activity of DS-5573a is mediated by effector cells, and this mAb could be a promising antitumor therapy for patients with a wide range of B7-H3-expressing tumors. © 2016 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  15. The high-pressure phase diagram of synthetic epsomite (MgSO4·7H2O and MgSO4·7D2O) from ultrasonic and neutron powder diffraction measurements

    NASA Astrophysics Data System (ADS)

    Gromnitskaya, E. L.; Yagafarov, O. F.; Lyapin, A. G.; Brazhkin, V. V.; Wood, I. G.; Tucker, M. G.; Fortes, A. D.

    2013-03-01

    We present an ultrasonic and neutron powder diffraction study of crystalline MgSO4·7H2O (synthetic epsomite) and MgSO4·7D2O under pressure up to ~3 GPa near room temperature and up to ~2 GPa at lower temperatures. Both methods provide complementary data on the phase transitions and elasticity of magnesium sulphate heptahydrate, where protonated and deuterated counterparts exhibit very similar behaviour and properties. Under compression in the declared pressure intervals, we observed three different sequences of phase transitions: between 280 and 295 K, phase transitions occurred at approximately 1.4, 1.6, and 2.5 GPa; between 240 and 280 K, only a single phase transition occurred; below 240 K, there were no phase transformations. Overall, we have identified four new phase fields at high pressure, in addition to that of the room-pressure orthorhombic structure. Of these, we present neutron powder diffraction data obtained in situ in the three phase fields observed near room temperature. We present evidence that these high-pressure phase fields correspond to regions where MgSO4·7H2O decomposes to a lower hydrate by exsolving water. Upon cooling to liquid nitrogen temperatures, the ratio of shear modulus G to bulk modulus B increases and we observe elastic softening of both moduli with pressure, which may be a precursor to pressure-induced amorphization. These observations may have important consequences for modelling the interiors of icy planetary bodies in which hydrated sulphates are important rock-forming minerals, such as the large icy moons of Jupiter, influencing their internal structure, dynamics, and potential for supporting life.

  16. Tumor Therapeutics Work as Stress Inducers to Enhance Tumor Sensitivity to Natural Killer (NK) Cell Cytolysis by Up-regulating NKp30 Ligand B7-H6.

    PubMed

    Cao, Guoshuai; Wang, Jian; Zheng, Xiaodong; Wei, Haiming; Tian, Zhigang; Sun, Rui

    2015-12-11

    Immune cells are believed to participate in initiating anti-tumor effects during regular tumor therapy such as chemotherapy, radiation, hyperthermia, and cytokine injection. One of the mechanisms underlying this process is the expression of so-called stress-inducible immunostimulating ligands. Although the activating receptor NKG2D has been proven to play roles in tumor therapy through targeting its ligands, the role of NKp30, another key activating receptor, is seldom addressed. In this study, we found that the NKp30 ligand B7-H6 was widely expressed in tumor cells and closely correlated to their susceptibility to NK cell lysis. Further studies showed that treatment of tumor cells with almost all standard tumor therapeutics, including chemotherapy (cisplatin, 5-fluorouracil), radiation therapy, non-lethal heat shock, and cytokine therapy (TNF-α), could up-regulate the expression of B7-H6 in tumor cells and enhance tumor sensitivity to NK cell cytolysis. B7-H6 shRNA treatment effectively dampened sensitization of tumor cells to NK-mediated lysis. Our study not only reveals the possibility that tumor therapeutics work as stress inducers to enhance tumor sensitivity to NK cell cytolysis but also suggests that B7-H6 could be a potential target for tumor therapy in the future.

  17. Amyloid-beta (Aβ) D7H mutation increases oligomeric Aβ42 and alters properties of Aβ-zinc/copper assemblies.

    PubMed

    Chen, Wei-Ting; Hong, Chen-Jee; Lin, Ya-Tzu; Chang, Wen-Han; Huang, He-Ting; Liao, Jhih-Ying; Chang, Yu-Jen; Hsieh, Yi-Fang; Cheng, Chih-Ya; Liu, Hsiu-Chih; Chen, Yun-Ru; Cheng, Irene H

    2012-01-01

    Amyloid precursor protein (APP) mutations associated with familial Alzheimer's disease (AD) usually lead to increases in amyloid β-protein (Aβ) levels or aggregation. Here, we identified a novel APP mutation, located within the Aβ sequence (Aβ(D7H)), in a Taiwanese family with early onset AD and explored the pathogenicity of this mutation. Cellular and biochemical analysis reveal that this mutation increased Aβ production, Aβ42/40 ratio and prolonged Aβ42 oligomer state with higher neurotoxicity. Because the D7H mutant Aβ has an additional metal ion-coordinating residue, histidine, we speculate that this mutation may promote susceptibility of Aβ to ion. When co-incubated with Zn(2+) or Cu(2+), Aβ(D7H) aggregated into low molecular weight oligomers. Together, the D7H mutation could contribute to AD pathology through a "double punch" effect on elevating both Aβ production and oligomerization. Although the pathogenic nature of this mutation needs further confirmation, our findings suggest that the Aβ N-terminal region potentially modulates APP processing and Aβ aggregation, and further provides a genetic indication of the importance of Zn(2+) and Cu(2+) in the etiology of AD.

  18. An Event Restriction Interval Theory of Tense

    ERIC Educational Resources Information Center

    Beamer, Brandon Robert

    2012-01-01

    This dissertation presents a novel theory of tense and tense-like constructions. It is named after a key theoretical component of the theory, the event restriction interval. In Event Restriction Interval (ERI) Theory, sentences are semantically evaluated relative to an index which contains two key intervals, the evaluation interval and the event…

  19. Evolution of the B7 family: Co-evolution of B7H6 and NKp30, identification of a new B7 family member, B7H7, and of B7’s historical relationship with the MHC

    PubMed Central

    Flajnik, Martin F.; Tlapakova, Tereza; Criscitiello, Michael F.; Krylov, Vladimir; Ohta, Yuko

    2013-01-01

    The B7 family of genes is essential in the regulation of the adaptive immune system. Most B7 family members contain both variable (V)- and constant (C)-type domains of the immunoglobulin superfamily (IgSF). Through in silico screening of the Xenopus genome and subsequent phylogenetic analysis, we found novel genes belonging to the B7 family, one of which is the recently discovered B7H6. Humans and rats have a single B7H6 gene, however many B7H6 genes were detected in a single large cluster in the Xenopus genome. The B7H6 expression patterns also varied in a species-specific manner. Human B7H6 binds to the activating natural killer receptor, NKp30. While the NKp30 gene is single-copy and maps to the MHC in most vertebrates, many Xenopus NKp30 genes were found in a cluster on a separate chromosome that does not harbor the MHC. Indeed, in all species so far analyzed from sharks to mammals, the number of NKp30 and B7H6 genes correlates well, suggestive of receptor-ligand co-evolution. Furthermore, we identified a Xenopus-specific B7 homolog (B7HXen) and revealed its close linkage to B2M, which we have demonstrated previously to have been originally encoded in the MHC. Thus, our study provides further proof that the B7 precursor was included in the proto MHC. Additionally, the comparative analysis revealed a new B7 family member, B7H7, which was previously designated in the literature as an unknown gene, HHLA2. PMID:22488247

  20. High resolution time interval counter

    DOEpatents

    Condreva, K.J.

    1994-07-26

    A high resolution counter circuit measures the time interval between the occurrence of an initial and a subsequent electrical pulse to two nanoseconds resolution using an eight megahertz clock. The circuit includes a main counter for receiving electrical pulses and generating a binary word--a measure of the number of eight megahertz clock pulses occurring between the signals. A pair of first and second pulse stretchers receive the signal and generate a pair of output signals whose widths are approximately sixty-four times the time between the receipt of the signals by the respective pulse stretchers and the receipt by the respective pulse stretchers of a second subsequent clock pulse. Output signals are thereafter supplied to a pair of start and stop counters operable to generate a pair of binary output words representative of the measure of the width of the pulses to a resolution of two nanoseconds. Errors associated with the pulse stretchers are corrected by providing calibration data to both stretcher circuits, and recording start and stop counter values. Stretched initial and subsequent signals are combined with autocalibration data and supplied to an arithmetic logic unit to determine the time interval in nanoseconds between the pair of electrical pulses being measured. 3 figs.

  1. High resolution time interval counter

    DOEpatents

    Condreva, Kenneth J.

    1994-01-01

    A high resolution counter circuit measures the time interval between the occurrence of an initial and a subsequent electrical pulse to two nanoseconds resolution using an eight megahertz clock. The circuit includes a main counter for receiving electrical pulses and generating a binary word--a measure of the number of eight megahertz clock pulses occurring between the signals. A pair of first and second pulse stretchers receive the signal and generate a pair of output signals whose widths are approximately sixty-four times the time between the receipt of the signals by the respective pulse stretchers and the receipt by the respective pulse stretchers of a second subsequent clock pulse. Output signals are thereafter supplied to a pair of start and stop counters operable to generate a pair of binary output words representative of the measure of the width of the pulses to a resolution of two nanoseconds. Errors associated with the pulse stretchers are corrected by providing calibration data to both stretcher circuits, and recording start and stop counter values. Stretched initial and subsequent signals are combined with autocalibration data and supplied to an arithmetic logic unit to determine the time interval in nanoseconds between the pair of electrical pulses being measured.

  2. Crystal structure of a new amine nitrate: 4-dimethylaminopyridinium nitrate (C{sub 7}H{sub 11}N{sub 2})NO{sub 3}

    SciTech Connect

    Benhassan, D. Rekik, W.; Naïli, H.; Ślepokura, Katarzyna

    2015-12-15

    The title compound (C{sub 7}H{sub 11}N{sub 2})NO{sub 3} (I) was obtained by the slow evaporation method at room temperature. Its crystal structure consists of organic cations (C{sub 7}H{sub 11}N{sub 2}){sup +} and nitrate anions (NO{sub 3}){sup –} linked by two types of hydrogen bonds. Each monoprotonated nitrogen atom, called bifurcated, is engaged in two N–H···O hydrogen bonds with two symmetric oxygen atoms. In addition, the crystal structure stability is established by C–H···O hydrogen bonds that ensure the formation of infinite layers, parallel to (001) plane. These layers are related together through π···π interactions established between aromatic amines.

  3. Apoptosis induced by the Tibetan herbal remedy PADMA 28 in the T cell-derived lymphocytic leukaemia cell line CEM-C7H2

    PubMed Central

    Jenny, Marcel; Schwaiger, Wolfgang; Bernhard, David; Wrulich, Oliver A; Cosaceanu, Daria; Fuchs, Dietmar; Ueberall, Florian

    2005-01-01

    The Tibetan herbal remedy PADMA 28 revealed promising results to support treatment of atherosclerosis, Charot syndrome (intermittent claudication), chronic active hepatitis and infection of the respiratory tract. The remedy was confirmed to be closely linked with anti- and pro-oxidative properties in vitro. In this study, apoptogenic and survival effects of PADMA 28 were investigated in the T cell-derived lymphocytic leukaemia cell line CEM-C7H2. PADMA 28 led to a concentration-dependent inhibition of cell proliferation accompanied by the accumulation of CEM-C7H2 cells in subG1 phase, fragmentation of poly (ADP-ribose) polymerase (PARP) and nuclear body formation. Treatment with PADMA 28 rescued to some extent cells over-expressing Bcl-2 from apoptosis. This finding suggests that the mechanism of action of PADMA 28 may be via interference with Bcl-2 triggered survival pathways. PMID:16138918

  4. Development and validation of a liquid medium (M7H9C) for routine culture of Mycobacterium avium subsp. paratuberculosis to replace modified Bactec 12B medium.

    PubMed

    Whittington, Richard J; Whittington, Ann-Michele; Waldron, Anna; Begg, Douglas J; de Silva, Kumi; Purdie, Auriol C; Plain, Karren M

    2013-12-01

    Liquid culture of Mycobacterium avium subsp. paratuberculosis from clinical samples, such as feces, is the most sensitive antemortem test for the diagnosis of Johne's disease in ruminants. In Australia, New Zealand, the United States, and some other countries, the Bactec 460 system with modified Bactec 12B medium (Becton, Dickinson) has been the most commonly used liquid culture system, but it was discontinued in 2012. In this study, a new liquid culture medium, M7H9C, was developed. It consists of a Middlebrook 7H9 medium base with added Casitone, albumin, dextrose, catalase, egg yolk, mycobactin J, and a cocktail of antibiotics. We found that polyoxyethylene stearate (POES) was not essential for the cultivation of M. avium subsp. paratuberculosis in either the Bactec 12B or the M7H9C medium. The limit of detection determined using pure cultures of the C and S strains of M. avium subsp. paratuberculosis was 7 bacilli per 50 μl inoculum in the two media. The new medium was validated using 784 fecal and tissue samples from sheep and cattle, >25% of which contained viable M. avium subsp. paratuberculosis. Discrepant results for the clinical samples between the two media were mostly associated with samples that contained <10 viable bacilli per gram, but these results were relatively uncommon, and the performances of the two media were not significantly different. M7H9C medium was less than half the cost of the Bactec 12B medium and did not require regular examination during incubation, but a confirmatory IS900 PCR test had to be performed on every culture after the predetermined incubation period.

  5. Regioselective multi-component synthesis of 1H-pyrazolo[3,4-d]pyrimidine-6(7H)-thiones.

    PubMed

    Safaei, Shirin; Mohammadpoor-Baltork, Iraj; Khosropour, Ahmad Reza; Moghadam, Majid; Tangestaninejad, Shahram; Mirkhani, Valiollah

    2012-08-01

    A variety of pyrazolo[3,4-d]pyrimidine-6(7H)-thione derivatives were easily synthesized with a novel, simple, efficient, and regioselective method via three-component condensation reaction of 5-methyl-1H-pyrazol-3-amine, arylisothiocyanates, and aldehydes in the presence of catalytic amount of p-toluenesulfonic acid (p-TSA) in 1-butyl-3-methylimidazolium bromide ionic liquid with excellent yields and short reaction times.

  6. Long Carbon Chains in the Warm Carbon-chain-chemistry Source L1527: First Detection of C7H in Molecular Clouds

    NASA Astrophysics Data System (ADS)

    Araki, Mitsunori; Takano, Shuro; Sakai, Nami; Yamamoto, Satoshi; Oyama, Takahiro; Kuze, Nobuhiko; Tsukiyama, Koichi

    2017-09-01

    Long carbon-chain molecules were searched for toward the low-mass star-forming region L1527, which is a prototypical source of warm carbon-chain chemistry (WCCC), using the 100 m Green Bank Telescope. Long carbon-chain molecules, C7H (2Π1/2), C6H (2Π3/2 and 2Π1/2), CH3C4H, and C6H2 (cumulene carbene, CCCCCCH2), and cyclic species of C3H and C3H2O were detected. In particular, C7H was detected for the first time in molecular clouds. The column density of C7H is determined to be 6 × 1010 cm‑2. The column densities of the carbon-chain molecules including CH3C4H and C6H in L1527 relative to those in the starless dark cloud Taurus Molecular Cloud-1 Cyanopolyyne Peak (TMC-1 CP) tend to be systematically lower for long carbon-chain lengths. However, the column densities of C7H and C6H2 do not follow this trend and are found to be relatively abundant in L1527. This result implies that these long carbon-chain molecules are remnants of the cold starless phase. The results—that both the remnants and WCCC products are observed toward L1527—are consistent with the suggestion that the protostar can also be born in the parent core at a relatively early stage in the chemical evolution.

  7. Environmental, Health and Safety Assessment: ATS 7H Program (Phase 3R) Test Activities at the GE Power Systems Gas Turbine Manufacturing Facility, Greenville, SC

    SciTech Connect

    1998-11-17

    International Technology Corporation (IT) was contracted by General Electric Company (GE) to assist in the preparation of an Environmental, Health and Safety (HI&3) assessment of the implementation of Phase 3R of the Advanced Turbine System (ATS) 7H program at the GE Gas Turbines facility located in Greenville, South Carolina. The assessment was prepared in accordance with GE's contractual agreement with the U.S. Department of Energy (GE/DOE Cooperative Agreement DE-FC21-95MC3 1176) and supports compliance with the requirements of the National Environmental Policy Act of 1970. This report provides a summary of the EH&S review and includes the following: General description of current site operations and EH&S status, Description of proposed ATS 7H-related activities and discussion of the resulting environmental, health, safety and other impacts to the site and surrounding area. Listing of permits and/or licenses required to comply with federal, state and local regulations for proposed 7H-related activities. Assessment of adequacy of current and required permits, licenses, programs and/or plans.

  8. Crystal structure of magnesium selenate hepta­hydrate, MgSeO4·7H2O, from neutron time-of-flight data

    PubMed Central

    Fortes, A. Dominic; Gutmann, Matthias J.

    2014-01-01

    MgSeO4·7H2O is isostructural with the analogous sulfate, MgSO4·7H2O, consisting of isolated [Mg(H2O)6]2+ octa­hedra and [SeO4]2− tetra­hedra, linked by O—H⋯O hydrogen bonds, with a single inter­stitial lattice water mol­ecule. As in the sulfate, the [Mg(H2O)6]2+ coordination octa­hedron is elongated along one axis due to the tetra­hedral coordination of the two apical water mol­ecules; these have Mg—O distances of ∼2.10 Å, whereas the remaining four trigonally coordinated water mol­ecules have Mg—O distances of ∼2.05 Å. The mean Se—O bond length is 1.641 Å and is in excellent agreement with other selenates. The unit-cell volume of MgSeO4·7H2O at 10 K is 4.1% larger than that of the sulfate at 2 K, although this is not uniform; the greater part of the expansion is along the a axis of the crystal. PMID:25309161

  9. [Raman spectral investigations on the phase transition behaviors of MgSO4.7H2O crystals in different efflorescence processes].

    PubMed

    Wang, Feng; Zhang, Yun-hong

    2011-03-01

    In the present paper, the in situ confocal Raman spectra of MgSO4.7H2O crystal in different efflorescence processes were obtained through changing relative humidities in differernt ways. Thus, detailed investigation of phase transition of MgSO4.7H2O crystal was achieved. At 3% RH, the phase transition of MgSO4 crystal from MgSO4.7H2O to MgSO4.3H2O both occurred in the fast-efflorescence and slow-efflorescence processes. However, in the deliquescence process, distinct phase transition behaviors were found between the MgSO4.3H2O crystals which formed in different efflorescence processes, the MgSO4. 3H20 crystals formed in fast-efflorescence process transformed to MgSO4.6H2O crystals at 70% RH in the deliquescence process. On the contrary, the MgSO4.3H2O crystals formed in slow-efflorescence process deliquesced to supersaturated MgSO4 droplet. The studies indicated that there is a correlation between the phase transition behaviors and ways of changing RH for the different MgSO4 crystal hydrates.

  10. Crystal structure of magnesium selenate hepta-hydrate, MgSeO4·7H2O, from neutron time-of-flight data.

    PubMed

    Fortes, A Dominic; Gutmann, Matthias J

    2014-09-01

    MgSeO4·7H2O is isostructural with the analogous sulfate, MgSO4·7H2O, consisting of isolated [Mg(H2O)6](2+) octa-hedra and [SeO4](2-) tetra-hedra, linked by O-H⋯O hydrogen bonds, with a single inter-stitial lattice water mol-ecule. As in the sulfate, the [Mg(H2O)6](2+) coordination octa-hedron is elongated along one axis due to the tetra-hedral coordination of the two apical water mol-ecules; these have Mg-O distances of ∼2.10 Å, whereas the remaining four trigonally coordinated water mol-ecules have Mg-O distances of ∼2.05 Å. The mean Se-O bond length is 1.641 Å and is in excellent agreement with other selenates. The unit-cell volume of MgSeO4·7H2O at 10 K is 4.1% larger than that of the sulfate at 2 K, although this is not uniform; the greater part of the expansion is along the a axis of the crystal.

  11. In acute myeloid leukemia, B7-H1 (PD-L1) protection of blasts from cytotoxic T cells is induced by TLR ligands and interferon-gamma and can be reversed using MEK inhibitors.

    PubMed

    Berthon, Céline; Driss, Virginie; Liu, Jizhong; Kuranda, Klaudia; Leleu, Xavier; Jouy, Nathalie; Hetuin, Dominique; Quesnel, Bruno

    2010-12-01

    B7-H1 (PD-L1) is a B7-related protein that inhibits T-cell responses. B7-H1 participates in the immunoescape of cancer cells and is also involved in the long-term persistence of leukemic cells in a mouse model of leukemia. B7-H1 can be constitutively expressed by cancer cells, but is also induced by various stimuli. Therefore, we examined the constitutive and inducible expression of B7-H1 and the consequences of this expression in human acute myeloid leukemia (AML). We analyzed B7-H1 expression in a cohort of 79 patients with AML. In addition, we studied blast cells after incubation with interferon-gamma or toll-like receptors (TLR) ligands. Finally, we evaluated functionality of cytotoxic T-cell activity against blast cells. Expression of B7-H1 upon diagnosis was high in 18% of patients. Expression of TLR2, 4 and 9 was detected in one-third of AML samples. Expression of TLR2 and TLR4 ligands or IFN-γ induced by B7-H1 was found to protect AML cells from CTL-mediated lysis. Spontaneous B7-H1 expression was also found to be enhanced upon relapse in some patients. MEK inhibitors, including UO126 and AZD6244, reduced B7-H1 expression and restored CTL-mediated lysis of blast cells. In AML, B7-H1 expression by blasts represents a possible immune escape mechanism. The inducibility of B7-H1 expression by IFN-γ or TLR ligands suggests that various stimuli, either produced during the immune response against leukemia cells or released by infectious microorganisms, could protect leukemic cells from T cells. The efficacy of MEK inhibitors against B7-H1-mediated inhibition of CTLs suggests a possible cancer immunotherapy strategy using targeted drugs.

  12. Orders on Intervals Over Partially Ordered Sets: Extending Allen's Algebra and Interval Graph Results

    SciTech Connect

    Zapata, Francisco; Kreinovich, Vladik; Joslyn, Cliff A.; Hogan, Emilie A.

    2013-08-01

    To make a decision, we need to compare the values of quantities. In many practical situations, we know the values with interval uncertainty. In such situations, we need to compare intervals. Allen’s algebra describes all possible relations between intervals on the real line, and ordering relations between such intervals are well studied. In this paper, we extend this description to intervals in an arbitrary partially ordered set (poset). In particular, we explicitly describe ordering relations between intervals that generalize relation between points. As auxiliary results, we provide a logical interpretation of the relation between intervals, and extend the results about interval graphs to intervals over posets.

  13. Humanized Affinity-matured Monoclonal Antibody 8H9 Has Potent Antitumor Activity and Binds to FG Loop of Tumor Antigen B7-H3.

    PubMed

    Ahmed, Mahiuddin; Cheng, Ming; Zhao, Qi; Goldgur, Yehuda; Cheal, Sarah M; Guo, Hong-fen; Larson, Steven M; Cheung, Nai-kong V

    2015-12-11

    B7-H3 (CD276) is both an inhibitory ligand for natural killer cells and T cells and a tumor antigen that is widely expressed among human solid tumors. Anti-B7-H3 mouse monoclonal antibody 8H9 has been successfully used for radioimmunotherapy for patients with B7-H3(+) tumors. We present the humanization, affinity maturation, and epitope mapping of 8H9 based on structure determination, modeling, and yeast display methods. The crystal structure of ch8H9 Fab fragment was solved to 2.5-Å resolution and used as a template for humanization. By displaying the humanized 8H9 single chain Fv (scFv) on the surface of yeast, the affinity was matured by sequential random mutagenesis and fluorescence-activated cell sorting. Six mutations (three in the complementarity-determining region and three in the framework regions) were identified and incorporated into an affinity-matured humanized 8H9 construct (hu8H9-6m) and an affinity-matured chimeric 8H9 construct (ch8H9-6m). The hu8H9-6m scFv had a 160-fold improvement in affinity (0.9 nm KD) compared with parental hu8H9 scFv (144 nm KD). The IgG formats of ch8H9-6m and hu8H9-6m (nanomolar to subnanomolar KD) had 2-9-fold enhancements in affinity compared with their parental forms, potent in vitro antibody-dependent cell-mediated cytotoxicity (0.1-0.3 μg/ml EC50), and high tumor uptake in mouse xenografts. Based on in silico docking studies and experimental validation, the molecular epitope of 8H9 was determined to be dependent on the FG loop of B7-H3, a region critical to its function in immunologic blockade and unique among anti-B7-H3 antibodies published to date. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  14. Pigeons' Choices between Fixed-Interval and Random-Interval Schedules: Utility of Variability?

    ERIC Educational Resources Information Center

    Andrzejewski, Matthew E.; Cardinal, Claudia D.; Field, Douglas P.; Flannery, Barbara A.; Johnson, Michael; Bailey, Kathleen; Hineline, Philip N.

    2005-01-01

    Pigeons' choosing between fixed-interval and random-interval schedules of reinforcement was investigated in three experiments using a discrete-trial procedure. In all three experiments, the random-interval schedule was generated by sampling a probability distribution at an interval (and in multiples of the interval) equal to that of the…

  15. Pigeons' Choices between Fixed-Interval and Random-Interval Schedules: Utility of Variability?

    ERIC Educational Resources Information Center

    Andrzejewski, Matthew E.; Cardinal, Claudia D.; Field, Douglas P.; Flannery, Barbara A.; Johnson, Michael; Bailey, Kathleen; Hineline, Philip N.

    2005-01-01

    Pigeons' choosing between fixed-interval and random-interval schedules of reinforcement was investigated in three experiments using a discrete-trial procedure. In all three experiments, the random-interval schedule was generated by sampling a probability distribution at an interval (and in multiples of the interval) equal to that of the…

  16. Calculations of phase equilibrium parameters of the quaternary systems KBr-K2SO4-K2B4O7-H2O and NaBr-Na2SO4-Na2B4O7-H2O at 298 K

    NASA Astrophysics Data System (ADS)

    Cui, Rui-Zhi; Wang, Dan; Yang, Yu-Yan; Sang, Shi-Hua

    2017-07-01

    Some of the parameters and equilibrium constants of quaternary salts solutions KBr-K2SO4-K2B4O7-H2O and NaBr-Na2SO4-Na2B4O7-H2O at 298 K are calculated using the correlation equation of the Pitzer parameters. The solubilities data of the ternary subsystems were fitted by multiple linear regression method. The phase diagram was plotted. A comparison between the calculated and experimental results for the systems shows that the predicted solubilities agree well with experimental data.

  17. Weighted regression analysis and interval estimators

    Treesearch

    Donald W. Seegrist

    1974-01-01

    A method for deriving the weighted least squares estimators for the parameters of a multiple regression model. Confidence intervals for expected values, and prediction intervals for the means of future samples are given.

  18. Interpregnancy interval and obstetrical complications.

    PubMed

    Shachar, Bat Zion; Lyell, Deirdre J

    2012-09-01

    Obstetricians are often presented with questions regarding the optimal interpregnancy interval (IPI). Short IPI has been associated with adverse perinatal and maternal outcomes, ranging from preterm birth and low birth weight to neonatal and maternal morbidity and mortality. Long IPI has in turn been associated with increased risk for preeclampsia and labor dystocia. In this review, we discuss the data regarding these associations along with recent studies revealing associations of short IPI with birth defects, schizophrenia, and autism. The optimal IPI may vary for different subgroups. We discuss the consequences of short IPI in women with a prior cesarean section, in particular the increased risk for uterine rupture and the considerations regarding a trial of labor in this subgroup. We review studies examining the interaction between short IPI and advanced maternal age and discuss the risk-benefit assessment for these women. Finally, we turn our attention to women after a stillbirth or an abortion, who often desire to conceive again with minimal delay. We discuss studies speaking in favor of a shorter IPI in this group. The accumulated data allow for the reevaluation of current IPI recommendations and management guidelines for women in general and among subpopulations with special circumstances. In particular, we suggest lowering the current minimal IPI recommendation to only 18 months (vs 24 months according to the latest World Health Organization recommendations), with even shorter recommended minimal IPI for women of advanced age and those who conceive after a spontaneous or induced abortion.

  19. The Measurement of the QT Interval

    PubMed Central

    Postema, Pieter G; Wilde, Arthur A.M

    2014-01-01

    The evaluation of every electrocardiogram should also include an effort to interpret the QT interval to assess the risk of malignant arrhythmias and sudden death associated with an aberrant QT interval. The QT interval is measured from the beginning of the QRS complex to the end of the T-wave, and should be corrected for heart rate to enable comparison with reference values. However, the correct determination of the QT interval, and its value, appears to be a daunting task. Although computerized analysis and interpretation of the QT interval are widely available, these might well over- or underestimate the QT interval and may thus either result in unnecessary treatment or preclude appropriate measures to be taken. This is particularly evident with difficult T-wave morphologies and technically suboptimal ECGs. Similarly, also accurate manual assessment of the QT interval appears to be difficult for many physicians worldwide. In this review we delineate the history of the measurement of the QT interval, its underlying pathophysiological mechanisms and the current standards of the measurement of the QT interval, we provide a glimpse into the future and we discuss several issues troubling accurate measurement of the QT interval. These issues include the lead choice, U-waves, determination of the end of the T-wave, different heart rate correction formulas, arrhythmias and the definition of normal and aberrant QT intervals. Furthermore, we provide recommendations that may serve as guidance to address these complexities and which support accurate assessment of the QT interval and its interpretation. PMID:24827793

  20. Min and Max Extreme Interval Values

    ERIC Educational Resources Information Center

    Jance, Marsha L.; Thomopoulos, Nick T.

    2011-01-01

    The paper shows how to find the min and max extreme interval values for the exponential and triangular distributions from the min and max uniform extreme interval values. Tables are provided to show the min and max extreme interval values for the uniform, exponential, and triangular distributions for different probabilities and observation sizes.

  1. NMR structural studies of the ionizing radiation adduct 7-hydro-8-oxodeoxyguanosine (8-oxo-7H-dG) opposite deoxyadenosine in a DNA duplex. 8-oxo-7H-dG(syn)ter dot dA(anti) alignment at lesion site

    SciTech Connect

    Kouchakdjian, M.; Patel, D.J. ); Bodepudi, V.; Shibutani, S.; Eisenberg, M.; Johnson, F.; Grollman, A.P. )

    1991-02-05

    Proton NMR studies are reported on the complementary d(C1-C2-A3-C4-T5-A6-oxo-G7-T8-C9-A10-C11-C12){center dot}d(G13-G14-T15-G16-A17-A18-T19-A20-G21-T22-G23-G24) dodecanucleotide duplex (designated 8-oxo-7H-dG{center dot}dA 12-mer), which contains a centrally located 7-hydro-8-oxodeoxyguanosine (8-oxo-7H-dG) residue, a group commonly found in DNA that has been exposed to ionizing radiation or oxidizing free radicals. From the NMR spectra it can be deduced that this moiety exists as two tautomers, or gives rise to two DNA conformations, that are in equilibrium and that exchange slowly. The present study focuses on the major component of the equilibrium that originates in the 6,8-dioxo tautomer of 8-oxo-7H-dG. The authors have assigned the exchangeable NH1, NH7, and NH{sub 2}-2 base protons located on the Watson-Crick and Hoogsteen edges of 8-oxo-7H-dG7 in the 8-oxo-7H-dG{center dot}dA 12-mer duplex, using an analysis of one- and two-dimensional nuclear Overhauser enhancement (NOE) data in H{sub 2}O solution. They were able to detect a set of intra- and interstrand NOEs between protons (exchangeable and nonexchangeable) on adjacent residues in the d(A6-oxo-G7-T8){center dot}d(A17-A18-T19) trinucleotide segment centered about the lesion site that establishes stacking of the oxo-dG7(syn){center dot}dA(anti) pair between stable Watson-Crick dA6{center dot}dT19 and dT8{center dot}A17 base pairs with minimal perturbation of the helix. The structural studies demonstrate that 8-oxo-7H-dG(syn){center dot}dA(anti) forms a stable pair in the interior of the helix, providing a basis for the observed incorporation of dA opposite 8-oxo-7H-dG when readthrough occurs past this oxidized nucleoside base.

  2. A vibrational spectroscopic study of a hydrated hydroxy-phosphate mineral fluellite, Al2(PO4)F2(OH)·7H2O.

    PubMed

    Cejka, Jiří; Sejkora, Jiří; Macek, Ivo; Frost, Ray L; López, Andrés; Scholz, Ricardo; Xi, Yunfei

    2014-05-21

    Raman and infrared spectra of two well-defined fluellite samples, Al2(PO4)F2(OH)·7H2O, from the Krásno near Horní Slavkov (Czech Republic) and Kapunda, South Australia (Australia) were studied and tentatively interpreted. Observed bands were assigned to the stretching and bending vibrations of phosphate tetrahedra, aluminum oxide/hydroxide/fluoride octahedra, water molecules and hydroxyl ions. Approximate O-H⋅⋅⋅O hydrogen bond lengths were inferred from the Raman and infrared spectra. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Volumetric Properties of the Mixture Diethyl carbonate C5H10O3 + C7H8 Toluene (VMSD1212, LB5158_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume B 'Binary Liquid Systems of Nonelectrolytes II' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Diethyl carbonate C5H10O3 + C7H8 Toluene (VMSD1212, LB5158_V)' providing data by calculation of molar excess volume from low-pressure density measurements at variable mole fraction and constant temperature.

  4. Volumetric Properties of the Mixture Diethyl carbonate C5H10O3 + C7H8 Toluene (VMSD1111, LB5155_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume B 'Binary Liquid Systems of Nonelectrolytes II' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Diethyl carbonate C5H10O3 + C7H8 Toluene (VMSD1111, LB5155_V)' providing data from direct low-pressure measurement of mass density at variable mole fraction and constant temperature, in the single-phase region(s).

  5. Volumetric Properties of the Mixture Cyclohexanone C6H10O + C7H8O Methyl phenyl ether (VMSD1511, LB4833_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume A 'Binary Liquid Systems of Nonelectrolytes I' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Cyclohexanone C6H10O + C7H8O Methyl phenyl ether (VMSD1511, LB4833_V)' providing data from direct measurement of low-pressure thermodynamic speed of sound at variable mole fraction and constant temperature, in the single-phase region(s).

  6. Volumetric Properties of the Mixture Cyclohexanone C6H10O + C7H8O Methyl phenyl ether (VMSD1212, LB4828_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume A 'Binary Liquid Systems of Nonelectrolytes I' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Cyclohexanone C6H10O + C7H8O Methyl phenyl ether (VMSD1212, LB4828_V)' providing data by calculation of molar excess volume from low-pressure density measurements at variable mole fraction and constant temperature.

  7. Volumetric Properties of the Mixture Cyclohexanone C6H10O + C7H8 Toluene (VMSD1111, LB4820_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume B 'Binary Liquid Systems of Nonelectrolytes II' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Cyclohexanone C6H10O + C7H8 Toluene (VMSD1111, LB4820_V)' providing data from direct low-pressure measurement of mass density at variable mole fraction and constant temperature, in the single-phase region(s).

  8. Volumetric Properties of the Mixture Cyclohexanone C6H10O + C7H8 Toluene (VMSD1511, LB4831_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume B 'Binary Liquid Systems of Nonelectrolytes II' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Cyclohexanone C6H10O + C7H8 Toluene (VMSD1511, LB4831_V)' providing data from direct measurement of low-pressure thermodynamic speed of sound at variable mole fraction and constant temperature, in the single-phase region(s).

  9. Volumetric Properties of the Mixture Cyclohexanone C6H10O + C7H14 Methylcyclohexane (VMSD1112, LB3138_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume B 'Binary Liquid Systems of Nonelectrolytes II' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Cyclohexanone C6H10O + C7H14 Methylcyclohexane (VMSD1112, LB3138_V)' providing data by calculation of mass density in the single-phase region(s) from low-pressure dilatometric measurements of the molar excess volume at variable mole fraction and constant temperature.

  10. Volumetric Properties of the Mixture Cyclohexanone C6H10O + C7H14 Methylcyclohexane (VMSD1211, LB3134_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume B 'Binary Liquid Systems of Nonelectrolytes II' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Cyclohexanone C6H10O + C7H14 Methylcyclohexane (VMSD1211, LB3134_V)' providing data from direct low-pressure dilatometric measurement of molar excess volume at variable mole fraction and constant temperature.

  11. Volumetric Properties of the Mixture Cyclohexanone C6H10O + C7H8 Toluene (VMSD1212, LB4826_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume B 'Binary Liquid Systems of Nonelectrolytes II' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Cyclohexanone C6H10O + C7H8 Toluene (VMSD1212, LB4826_V)' providing data by calculation of molar excess volume from low-pressure density measurements at variable mole fraction and constant temperature.

  12. Volumetric Properties of the Mixture Cyclohexanone C6H10O + C7H8O Methyl phenyl ether (VMSD1111, LB4823_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume A 'Binary Liquid Systems of Nonelectrolytes I' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Cyclohexanone C6H10O + C7H8O Methyl phenyl ether (VMSD1111, LB4823_V)' providing data from direct low-pressure measurement of mass density at variable mole fraction and constant temperature, in the single-phase region(s).

  13. Intervals in evolutionary algorithms for global optimization

    SciTech Connect

    Patil, R.B.

    1995-05-01

    Optimization is of central concern to a number of disciplines. Interval Arithmetic methods for global optimization provide us with (guaranteed) verified results. These methods are mainly restricted to the classes of objective functions that are twice differentiable and use a simple strategy of eliminating a splitting larger regions of search space in the global optimization process. An efficient approach that combines the efficient strategy from Interval Global Optimization Methods and robustness of the Evolutionary Algorithms is proposed. In the proposed approach, search begins with randomly created interval vectors with interval widths equal to the whole domain. Before the beginning of the evolutionary process, fitness of these interval parameter vectors is defined by evaluating the objective function at the center of the initial interval vectors. In the subsequent evolutionary process the local optimization process returns an estimate of the bounds of the objective function over the interval vectors. Though these bounds may not be correct at the beginning due to large interval widths and complicated function properties, the process of reducing interval widths over time and a selection approach similar to simulated annealing helps in estimating reasonably correct bounds as the population evolves. The interval parameter vectors at these estimated bounds (local optima) are then subjected to crossover and mutation operators. This evolutionary process continues for predetermined number of generations in the search of the global optimum.

  14. The C7H5 Fulvenallenyl Radical as a Combustion Intermediate: Potential New Pathways to Two- and Three-Ring PAHs

    NASA Astrophysics Data System (ADS)

    da Silva, Gabriel; Bozzelli, Joseph W.

    2009-10-01

    This study proposes the existence of a new, highly resonantly stabilized free radical, fulvenallenyl (C7H5). Fulvenallenyl forms from dissociation or abstraction of the weak H atoms in the C7H6 compounds fulvenallene and 1-ethynylcyclopentadiene, which were recently identified as intermediates in the combustion of aromatic fuels and in sooting flames. The fulvenallenyl radical shares properties of the propargyl and cyclopentadienyl radicals, and like these species, we propose that fulvenallenyl has a significant resonance stabilization energy. This resonance energy is lost upon further reaction, making the fulvenallenyl radical resistant to oxidation and thermal decomposition. As with the resonantly stabilized radicals propargyl and cyclopentadienyl, fulvenallenyl is expected to react with other radicals in molecular weight growth reactions. Several pathways are proposed for self-reaction and cross-reactions of fulvenallenyl that directly produce two- and three-ring PAHs like naphthalene, diphenyl, and phenanthrene. Rate constants are calculated for H atom abstraction from fulvenallene and 1-ethynylcyclopentadiene by the common radicals H, OH, and CH3, to facilitate the inclusion of fulvenallenyl in kinetic models.

  15. Increased antigen presentation but impaired T cells priming after upregulation of interferon-beta induced by lipopolysaccharides is mediated by upregulation of B7H1 and GITRL.

    PubMed

    Wang, Fang; Wang, Yan Yan; Li, Juan; You, Xiang; Qiu, Xin Hui; Wang, Yi Nan; Gao, Feng Guang

    2014-01-01

    Dendritic cells are able to present Ag-derived peptides on MHC class I and II molecules and induce T cells priming. Lipopolysaccharides (LPS), an activator of Toll-like 4 receptor (TLR4) signaling, has been demonstrated to facilitate Ag-presentation, up-regulate surface molecules expression but impair T cells priming. In this study, we investigated the effect of LPS on nicotine-enhanced DCs-dependent T cells priming and the mechanisms of LPS orchestrating the immunosuppressive program. We could demonstrate that the treatment with LPS resulted in increased surface molecules expression, enhanced Ag-presentation, up-regulated release of TGF-beta, TNF-alpha, IL-6, and IFN-beta. Concomititantly, the upregulation of IFN-beta in DCs induces the up-regulation of coinhibitory molecules B7H1 and GITRL, which cause an impaired activation of naïve Ag-specific T cells and the induction of T cell tolerance by enhancing B7H1-PD-1 interactions and promoting GITRL-GITL facilitated Treg generation, respectively. These data provide a mechanistic basis for the immunomodulatory action of IFN-beta which might open new possibilities in the development of therapeutic approaches aimed at the control of excessive immune response and persistent infection.

  16. Pyrolysis of Tropyl Radical (C7H7) and Benzyl Radical (C6H5CH2) in a Heated Micro-Reactor

    NASA Astrophysics Data System (ADS)

    Buckingham, Grant; Ellison, Barney; Porterfield, Jessica P.; Daily, John W.; Ahmed, Musahid; Robichaud, David; Nimlos, Mark R.

    2016-06-01

    Benzyl radical (C6H5CH2) is a crucial intermediate in the combustion and pyrolysis of substituted aromatic species that are common both in modern gasoline and potential future biofuels. The decomposition of benzyl radical is complicated and has been shown by isotopic labeling to require interesting isomerizations pathways. To better understand these pathways, a set of C7H7 radicals has been studied in a heated micro-reactor. Through multiple experiments, it has be shown that benzyl radical and cycloheptatrienyl (tropyl) radical (c-C7H7) do not interconvert, even at temperatures where both have completely thermally decomposed. To confirm this, tropyl radical has been studied directly and its pyrolysis is quite simple, only cyclopentadienyl radical (c-C5H5) and acetylene (HCCH) are formed. Cyclopentadienyl radical then decomposes to acetylene and propargyl radical (HCCCH2). These products have all been identified through use of tunable synchrotron radiation by confirming their respective photoionization spectra. Matrix isolation infrared (IR) spectroscopy has also been used to identity these products. A previously unanswered question in benzyl radical decomposition has been addressed by studying the pyrolysis of 2,5-norbornadiene, which indicates benzyl radical may decompose through a norbornadiene-like bicyclic radical intermediate. This pathways successfully predicts the correct isotopically labeled products observed previously during 13C labeled benzyl pyrolysis.

  17. Virus-like particles displaying H5, H7, H9 hemagglutinins and N1 neuraminidase elicit protective immunity to heterologous avian influenza viruses in chickens.

    PubMed

    Pushko, Peter; Tretyakova, Irina; Hidajat, Rachmat; Zsak, Aniko; Chrzastek, Klaudia; Tumpey, Terrence M; Kapczynski, Darrell R

    2017-01-15

    Avian influenza (AI) viruses circulating in wild birds pose a serious threat to public health. Human and veterinary vaccines against AI subtypes are needed. Here we prepared triple-subtype VLPs that co-localized H5, H7 and H9 antigens derived from H5N1, H7N3 and H9N2 viruses. VLPs also contained influenza N1 neuraminidase and retroviral gag protein. The H5/H7/H9/N1/gag VLPs were prepared using baculovirus expression. Biochemical, functional and antigenic characteristics were determined including hemagglutination and neuraminidase enzyme activities. VLPs were further evaluated in a chicken AI challenge model for safety, immunogenicity and protective efficacy against heterologous AI viruses including H5N2, H7N3 and H9N2 subtypes. All vaccinated birds survived challenges with H5N2 and H7N3 highly pathogenic AI (HPAI) viruses, while all controls died. Immune response was also detectable after challenge with low pathogenicity AI (LPAI) H9N2 virus suggesting that H5/H7/H9/N1/gag VLPs represent a promising approach for the development of broadly protective AI vaccine. Copyright © 2016. Published by Elsevier Inc.

  18. Aspects of Supercritical Turbulence: Direct Numerical Simulation of O2/H2 and C7H16/N2 Temporal Mixing Layers

    NASA Technical Reports Server (NTRS)

    Bellan, J.; Okongo, N. A.; Harstad, K. G.; Hutt, John (Technical Monitor)

    2002-01-01

    Results from Direct Numerical Simulations of temporal, supercritical mixing layers for two species systems are analyzed to elucidate species-specific turbulence aspects. The two species systems, O2/H2 and C7HG16/N2, have different thermodynamic characteristics; thus, although the simulations are performed at similar reduced pressure (ratio of the pressure to the critical pressure), the former system is dose to mixture ideality and has a relatively high solubility with respect to the latter, which exhibits strong departures from mixture ideality Due to the specified, smaller initial density stratification, the C7H16/N2 layers display higher growth and increased global molecular mixing as well as larger turbulence levels. However, smaller density gradients at the transitional state for the O2/H2 system indicate that on a local basis, the layer exhibits an enhanced mixing, this being attributed to the increased solubility and to mixture ideality. These thermodynamic features are shown to affect the irreversible entropy production (i.e. the dissipation), which is larger for the O2/H2 layer and is primarily concentrated in high density-gradient magnitude regions that are distortions of the initial density stratification boundary. In contrast, the regions of largest dissipation in the C7H16/N2 layer are located in high density-gradient magnitude regions resulting from the mixing of the two fluids.

  19. Capacitated max -Batching with Interval Graph Compatibilities

    NASA Astrophysics Data System (ADS)

    Nonner, Tim

    We consider the problem of partitioning interval graphs into cliques of bounded size. Each interval has a weight, and the weight of a clique is the maximum weight of any interval in the clique. This natural graph problem can be interpreted as a batch scheduling problem. Solving a long-standing open problem, we show NP-hardness, even if the bound on the clique sizes is constant. Moreover, we give a PTAS based on a novel dynamic programming technique for this case.

  20. Cross-linking of B7-H1 on EBV-transformed B cells induces apoptosis through reactive oxygen species production, JNK signaling activation, and fasL expression.

    PubMed

    Kim, Yeong Seok; Park, Ga Bin; Lee, Hyun-Kyung; Song, Hyunkeun; Choi, In-Hak; Lee, Wang Jae; Hur, Dae Young

    2008-11-01

    B7-H1 is a newly identified member of the B7 family with important regulatory functions in cell-mediated immune responses, and it is expressed in human immune cells and several tumors. We first observed that expression of surface B7-H1 on B cells was increased during the immortalization process by EBV, which is strongly related to both inflammation and tumorigenesis. Cross-linking of B7-H1 on EBV-transformed B cells using anti-B7-H1 Ab (clone 130002) induced reactive oxygen species (ROS) generation, mitochondrial disruption, release of apoptotic proteins from mitochondria, and subsequent apoptosis. Inhibition of caspases and ROS generation recovered B7-H1-mediated apoptosis and proteolytic activities of caspase-8, -9, and -3. We observed that B7-H1 stimulation induced both transcription and translation of fasL. ZB4, an antagonistic anti-fas Ab, and NOK-1, an antagonistic anti-fasL Ab, effectively blocked apoptosis without exerting any influence on ROS generation. N-acetylcysteine (NAC) completely blocked the induction of fasL mRNA and protein. We found that B7-H1 stimulation activated the phosphorylation of JNK and c-jun and down-regulated ERK1/2 and p-Akt. NAC blocked the activation of JNK and down-regulation of ERK, but both z-VAD-fmk (N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone) and ZB4 did not inhibit JNK activation of B7-H1 stimulation. SP600125 blocked fasL induction and apoptosis but did not affect ROS generation after B7-H1 stimulation. Taken together, we concluded that B7-H1-mediated apoptosis on EBV-transformed B cells may be involved in the induction of fasL, which is evoked by ROS generation and JNK activation after cross-linking of B7-H1. These results provide a new concept for understanding reverse signaling through B7-H1 and another mechanism of tumor immunotherapy using anti-B7-H1.

  1. Confidence Interval Procedures for Reliability Growth Analysis

    DTIC Science & Technology

    1977-06-01

    Plj2s tSAA - TECHNICAL RPORT NO. 197 CONFIDENCE INTERVAL PROCEDURES FOR RELIABILITY, GROWTH ANALYSIS LARRY H. CROW JUNE 1977 APPROVED FOR PUBLIC...dence Intervals for M(T). ¶-. fl [ ] 1 Siion IIS0III0N/AVAI Ale ITY ClOtS Next page is blank. So3 CONFIDENCE INTERVAL PROCIEDURIS• FOR RELTABILITY...and confidence interval procedures for the parameters B and P = X are presented in [l , [2], [4]. In the application of the Weibull process model to

  2. Confidence intervals for the MMPI-2.

    PubMed

    Munley, P H

    1991-08-01

    The confidence intervals for the Minnesota Multiphasic Personality Inventory (MMPI-2) clinical scales were investigated. Based on the clinical scale reliabilities published in the MMPI-2 manual, estimated true scores, standard errors of measurement for estimated true scores, and 95% confidence intervals centered around estimated true scores were calculated at 5-point MMPI-2 T-score intervals. The relationships between obtained T-scores, estimated true T-scores, scale reliabilities, and confidence intervals are discussed. The possible role of error measurement in defining scale high point and code types is noted.

  3. Interval and Contour Processing in Autism

    ERIC Educational Resources Information Center

    Heaton, Pamela

    2005-01-01

    High functioning children with autism and age and intelligence matched controls participated in experiments testing perception of pitch intervals and musical contours. The finding from the interval study showed superior detection of pitch direction over small pitch distances in the autism group. On the test of contour discrimination no group…

  4. Optimal Approximation of Quadratic Interval Functions

    NASA Technical Reports Server (NTRS)

    Koshelev, Misha; Taillibert, Patrick

    1997-01-01

    Measurements are never absolutely accurate, as a result, after each measurement, we do not get the exact value of the measured quantity; at best, we get an interval of its possible values, For dynamically changing quantities x, the additional problem is that we cannot measure them continuously; we can only measure them at certain discrete moments of time t(sub 1), t(sub 2), ... If we know that the value x(t(sub j)) at a moment t(sub j) of the last measurement was in the interval [x-(t(sub j)), x + (t(sub j))], and if we know the upper bound D on the rate with which x changes, then, for any given moment of time t, we can conclude that x(t) belongs to the interval [x-(t(sub j)) - D (t - t(sub j)), x + (t(sub j)) + D (t - t(sub j))]. This interval changes linearly with time, an is, therefore, called a linear interval function. When we process these intervals, we get an expression that is quadratic and higher order w.r.t. time t, Such "quadratic" intervals are difficult to process and therefore, it is necessary to approximate them by linear ones. In this paper, we describe an algorithm that gives the optimal approximation of quadratic interval functions by linear ones.

  5. 47 CFR 52.35 - Porting Intervals.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 3 2012-10-01 2012-10-01 false Porting Intervals. 52.35 Section 52.35 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES (CONTINUED) NUMBERING Number Portability § 52.35 Porting Intervals. (a) All telecommunications carriers required by the Commission to port...

  6. SINGLE-INTERVAL GAS PERMEABILITY ESTIMATION

    EPA Science Inventory

    Single-interval, steady-steady-state gas permeability testing requires estimation of pressure at a screened interval which in turn requires measurement of friction factors as a function of mass flow rate. Friction factors can be obtained by injecting air through a length of pipe...

  7. SINGLE-INTERVAL GAS PERMEABILITY ESTIMATION

    EPA Science Inventory

    Single-interval, steady-steady-state gas permeability testing requires estimation of pressure at a screened interval which in turn requires measurement of friction factors as a function of mass flow rate. Friction factors can be obtained by injecting air through a length of pipe...

  8. Interval and Contour Processing in Autism

    ERIC Educational Resources Information Center

    Heaton, Pamela

    2005-01-01

    High functioning children with autism and age and intelligence matched controls participated in experiments testing perception of pitch intervals and musical contours. The finding from the interval study showed superior detection of pitch direction over small pitch distances in the autism group. On the test of contour discrimination no group…

  9. Interpretation of Confidence Interval Facing the Conflict

    ERIC Educational Resources Information Center

    Andrade, Luisa; Fernández, Felipe

    2016-01-01

    As literature has reported, it is usual that university students in statistics courses, and even statistics teachers, interpret the confidence level associated with a confidence interval as the probability that the parameter value will be between the lower and upper interval limits. To confront this misconception, class activities have been…

  10. In acute myeloid leukemia, B7-H1 (PD-L1) protection of blasts from cytotoxic T cells is induced by TLR ligands and interferon-gamma and can be reversed using MEK inhibitors

    PubMed Central

    Berthon, Céline; Driss, Virginie; Liu, Jizhong; Kuranda, Klaudia; Leleu, Xavier; Jouy, Nathalie; Hetuin, Dominique

    2010-01-01

    B7-H1 (PD-L1) is a B7-related protein that inhibits T-cell responses. B7-H1 participates in the immunoescape of cancer cells and is also involved in the long-term persistence of leukemic cells in a mouse model of leukemia. B7-H1 can be constitutively expressed by cancer cells, but is also induced by various stimuli. Therefore, we examined the constitutive and inducible expression of B7-H1 and the consequences of this expression in human acute myeloid leukemia (AML). We analyzed B7-H1 expression in a cohort of 79 patients with AML. In addition, we studied blast cells after incubation with interferon-gamma or toll-like receptors (TLR) ligands. Finally, we evaluated functionality of cytotoxic T-cell activity against blast cells. Expression of B7-H1 upon diagnosis was high in 18% of patients. Expression of TLR2, 4 and 9 was detected in one-third of AML samples. Expression of TLR2 and TLR4 ligands or IFN-γ induced by B7-H1 was found to protect AML cells from CTL-mediated lysis. Spontaneous B7-H1 expression was also found to be enhanced upon relapse in some patients. MEK inhibitors, including UO126 and AZD6244, reduced B7-H1 expression and restored CTL-mediated lysis of blast cells. In AML, B7-H1 expression by blasts represents a possible immune escape mechanism. The inducibility of B7-H1 expression by IFN-γ or TLR ligands suggests that various stimuli, either produced during the immune response against leukemia cells or released by infectious microorganisms, could protect leukemic cells from T cells. The efficacy of MEK inhibitors against B7-H1-mediated inhibition of CTLs suggests a possible cancer immunotherapy strategy using targeted drugs. Electronic supplementary material The online version of this article (doi:10.1007/s00262-010-0909-y) contains supplementary material, which is available to authorized users. PMID:20814675

  11. Biomathematics and Interval Analysis: A Prosperous Marriage

    NASA Astrophysics Data System (ADS)

    Markov, S. M.

    2010-11-01

    In this survey paper we focus our attention on dynamical bio-systems involving uncertainties and the use of interval methods for the modelling study of such systems. The kind of envisioned uncertain systems are those described by a dynamical model with parameters bounded in intervals. We point out to a fruitful symbiosis between dynamical modelling in biology and computational methods of interval analysis. Both fields are presently in the stage of rapid development and can benefit from each other. We point out on recent studies in the field of interval arithmetic from a new perspective—the midpoint-radius arithmetic which explores the properties of error bounds and approximate numbers. The midpoint-radius approach provides a bridge between interval methods and the "uncertain but bounded" approach used for model estimation and identification. We briefly discuss certain recently obtained algebraic properties of errors and approximate numbers.

  12. Microscopic magnetic modeling for the spin-1/2 kagome compound [NH4]2 [ C7H14N][V7O6F18

    NASA Astrophysics Data System (ADS)

    Janson, Oleg; Tsirlin, Alexander A.; Rousochatzakis, Ioannis; Rosner, Helge; Stern, Raivo

    2014-03-01

    In the recently synthesised compound [NH4]2 [ C7H14N][V7O6F18 ] , magnetic S=1/2 V4+ atoms form an ideal kagome lattice [1 ]. Very recent μSR studies indicate the emergence of a gapless spin liquid state [2 ]. Using density functional theory calculations, we address the microscopic magnetic model of this interesting compound. We show that its peculiar symmetry gives rise to two inequivalent nearest-neighbor couplings. The behavior of the resulting spin model is studied using exact diagonalization and compared to the experiments. [1 ] F.H.Aidoudi et al., Nature Chem. 3, 810 (2011). [2 ] L.Clark et al., Phys. Rev. Lett. 110, 207208 (2013). OJ and AT were supported by the Mobilitas program of the ESF, grant numbers MJD447 and MTT77, respectively.

  13. Novel series of potent, nonsteroidal, selective androgen receptor modulators based on 7H-[1,4]oxazino[3,2-g]quinolin-7-ones.

    PubMed

    Higuchi, Robert I; Arienti, Kristen L; López, Francisco J; Mani, Neelakhanda S; Mais, Dale E; Caferro, Thomas R; Long, Yun Oliver; Jones, Todd K; Edwards, James P; Zhi, Lin; Schrader, William T; Negro-Vilar, Andrés; Marschke, Keith B

    2007-05-17

    Recent interest in orally available androgens has fueled the search for new androgens for use in hormone replacement therapy and as anabolic agents. In pursuit of this, we have discovered a series of novel androgen receptor modulators derived from 7H-[1,4]oxazino[3,2-g]quinolin-7-ones. These compounds were synthesized and evaluated in competitive binding assays and an androgen receptor transcriptional activation assay. A number of compounds from the series demonstrated single-digit nanomolar agonist activity in vitro. In addition, lead compound (R)-16e was orally active in established rodent models that measure androgenic and anabolic properties of these agents. In this assay, (R)-16e demonstrated full efficacy in muscle and only partially stimulated the prostate at 100 mg/kg. These data suggest that these compounds may be utilized as selective androgen receptor modulators or SARMs. This series represents a novel class of compounds for use in androgen replacement therapy.

  14. Structure and magnetism of the mono-layer hydrate Na 0.3NiO 2 ṡ 0.7H 2O

    NASA Astrophysics Data System (ADS)

    Park, S.; Yoon, W.-S.; Vogt, T.

    2007-04-01

    The mono-layer hydrate (Ni-MLH) Na 0.3NiO 2ṡ0.7H 2O was synthesized with an average Ni valence close to one in the bi-layer hydrate (Ni-BLH) Na 0.3NiO 2ṡ1.3H 2O. A weak unsaturated ferromagnetism and divergence of the magnetic susceptibilities of field and zero-field cooled samples of both Ni-MLH and Ni-BLH are observed. However, as a result of the increased three-dimensional electronic and magnetic character present in Ni-MLH, a frequency dependence of the AC magnetic susceptibility indicative of spin-glass-like behavior, as seen in Ni-BLH, was no longer observed.

  15. Partition coefficients of alpha-amylase in aqueous two-phase systems PEG + MgSO4.7H2O + H2O at 298 K.

    PubMed

    Blázquez, G; Camacho, F; González-Tello, P; Alarcón, F J

    1998-02-02

    Partition coefficients of alpha-amylase have been determined in a polyethylene glycol (average molecular mass 8000)/MgSO4.7H2O aqueous two-phase system at 298 K and the influence of polymer, salt and initial enzyme concentration on partition was investigated. Correlations are proposed which relates the partition coefficient to the initial enzyme concentration and the concentration difference between phases of polymer and salt. The free volume change, related to the densities of the separate phases, has a direct dependence with such polymer and salt concentration differences, respectively, and is then used to facilitate future estimations. Thus, the partition coefficient is a function of this physical parameter and the initial enzyme concentration employed (1.25, 2.50 and 5.00 g dm-3).

  16. Improved interval estimation of comparative treatment effects

    NASA Astrophysics Data System (ADS)

    Van Krevelen, Ryne Christian

    Comparative experiments, in which subjects are randomized to one of two treatments, are performed often. There is no shortage of papers testing whether a treatment effect exists and providing confidence intervals for the magnitude of this effect. While it is well understood that the object and scope of inference for an experiment will depend on what assumptions are made, these entities are not always clearly presented. We have proposed one possible method, which is based on the ideas of Jerzy Neyman, that can be used for constructing confidence intervals in a comparative experiment. The resulting intervals, referred to as Neyman-type confidence intervals, can be applied in a wide range of cases. Special care is taken to note which assumptions are made and what object and scope of inference are being investigated. We have presented a notation that highlights which parts of a problem are being treated as random. This helps ensure the focus on the appropriate scope of inference. The Neyman-type confidence intervals are compared to possible alternatives in two different inference settings: one in which inference is made about the units in the sample and one in which inference is made about units in a fixed population. A third inference setting, one in which inference is made about a process distribution, is also discussed. It is stressed that certain assumptions underlying this third type of inference are unverifiable. When these assumptions are not met, the resulting confidence intervals may cover their intended target well below the desired rate. Through simulation, we demonstrate that the Neyman-type intervals have good coverage properties when inference is being made about a sample or a population. In some cases the alternative intervals are much wider than necessary on average. Therefore, we recommend that researchers consider using our Neyman-type confidence intervals when carrying out inference about a sample or a population as it may provide them with more

  17. Empirical Bayes interval estimates that are conditionally equal to unadjusted confidence intervals or to default prior credibility intervals.

    PubMed

    Bickel, David R

    2012-02-21

    Problems involving thousands of null hypotheses have been addressed by estimating the local false discovery rate (LFDR). A previous LFDR approach to reporting point and interval estimates of an effect-size parameter uses an estimate of the prior distribution of the parameter conditional on the alternative hypothesis. That estimated prior is often unreliable, and yet strongly influences the posterior intervals and point estimates, causing the posterior intervals to differ from fixed-parameter confidence intervals, even for arbitrarily small estimates of the LFDR. That influence of the estimated prior manifests the failure of the conditional posterior intervals, given the truth of the alternative hypothesis, to match the confidence intervals. Those problems are overcome by changing the posterior distribution conditional on the alternative hypothesis from a Bayesian posterior to a confidence posterior. Unlike the Bayesian posterior, the confidence posterior equates the posterior probability that the parameter lies in a fixed interval with the coverage rate of the coinciding confidence interval. The resulting confidence-Bayes hybrid posterior supplies interval and point estimates that shrink toward the null hypothesis value. The confidence intervals tend to be much shorter than their fixed-parameter counterparts, as illustrated with gene expression data. Simulations nonetheless confirm that the shrunken confidence intervals cover the parameter more frequently than stated. Generally applicable sufficient conditions for correct coverage are given. In addition to having those frequentist properties, the hybrid posterior can also be motivated from an objective Bayesian perspective by requiring coherence with some default prior conditional on the alternative hypothesis. That requirement generates a new class of approximate posteriors that supplement Bayes factors modified for improper priors and that dampen the influence of proper priors on the credibility intervals. While

  18. Coevolution of MHC genes (LMP/TAP/class Ia, NKT-class Ib, NKp30-B7H6): lessons from cold-blooded vertebrates.

    PubMed

    Ohta, Yuko; Flajnik, Martin F

    2015-09-01

    Comparative immunology provides the long view of what is conserved across all vertebrate taxa versus what is specific to particular organisms or group of organisms. Regarding the major histocompatibility complex (MHC) and coevolution, three striking cases have been revealed in cold-blooded vertebrates: lineages of class Ia antigen-processing and -presenting genes, evolutionary conservation of NKT-class Ib recognition, and the ancient emergence of the natural cytotoxicity receptor NKp30 and its ligand B7H6. While coevolution of transporter associated with antigen processing (TAP) and class Ia has been documented in endothermic birds and two mammals, lineages of LMP7 are restricted to ectotherms. The unambiguous discovery of natural killer T (NKT) cells in Xenopus demonstrated that NKT cells are not restricted to mammals and are likely to have emerged at the same time in evolution as classical α/β and γ/δ T cells. NK cell receptors evolve at a rapid rate, and orthologues are nearly impossible to identify in different vertebrate classes. By contrast, we have detected NKp30 in all gnathostomes, except in species where it was lost. The recently discovered ligand of NKp30, B7H6, shows strong signs of coevolution with NKp30 throughout evolution, i.e. coincident loss or expansion of both genes in some species. NKp30 also offers an attractive IgSF candidate for the invasion of the RAG transposon, which is believed to have initiated T-cell receptor/immunoglobulin adaptive immunity. Besides reviewing these intriguing features of MHC evolution and coevolution, we offer suggestions for future studies and propose a model for the primordial or proto MHC. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. Coevolution of MHC genes (LMP/TAP/class Ia; NKT-class Ib; NKp30-B7H6): Lessons from cold-blooded vertebrates

    PubMed Central

    Ohta, Yuko; Flajnik, Martin F.

    2015-01-01

    Summary Comparative immunology provides the long view of what is conserved across all vertebrate taxa versus what is specific to particular organisms or group of organisms. Regarding the major histocompatibility complex (MHC) and coevolution, three striking cases have been revealed in cold-blooded vertebrates: lineages of class Ia antigen-processing and -presenting genes, evolutionary conservation of NKT-class Ib recognition, and the ancient emergence of the natural cytotoxicity receptor NKp30 and its ligand B7H6. While coevolution of transporter associated with antigen processing (TAP) and class Ia has been documented in endothermic birds and two mammals, lineages of LMP7 are restricted to ectotherms. The unambiguous discovery of natural killer T (NKT) cells in Xenopus demonstrated that NKT cells are not restricted to mammals and are likely to have emerged at the same time in evolution as classical α/β and γ/δ T cells. NK cell receptors evolve at a rapid rate, and orthologues are nearly impossible to identify in different vertebrate classes. By contrast, we have detected NKp30 in all gnathostomes, except in species where it was lost. The recently discovered ligand of NKp30, B7H6, shows strong signs of coevolution with NKp30 throughout evolution, i.e. coincident loss or expansion of both genes in some species. NKp30 also offers an attractive IgSF candidate for the invasion of the RAG transposon, which is believed to have initiated T-cell receptor/immunoglobulin adaptive immunity. Besides reviewing these intriguing features of MHC evolution and coevolution, we offer suggestions for future studies and propose a model for the primordial or proto MHC. PMID:26284468

  20. Electrical characterization, phase transition and vibrational spectroscopic investigations of a new organic-inorganic material (C7H10NO)SnCl3

    NASA Astrophysics Data System (ADS)

    Karoui, Sahel; Chouaib, Hassen; Kamoun, Slaheddine

    2017-10-01

    The X-ray powder analysis, thermogravimetric analysis, differential scanning calorimetry analysis, solid CP-MAS 13C NMR characterization, vibrational spectroscopy and complex impedance spectroscopic data have been carried out on (C7H10NO)SnCl3 compound. The results show that this compound exhibits a phase transition at 314 K which was characterized by 1H NMR between 298 and 336 K, differential scanning calorimetry (DSC), X-rays powder diffraction, Raman spectroscopy and dielectric measurements. The temperature dependence of the 1H NMR spectrum for (C7H10NO)SnCl3 could be explained by invoking reorientation of ammonium group of the 2-methoxyanilinium cation. The most important changes are observed for two lines at 3087 cm-1 and 3175 cm-1 (at room temperature) issued from asymmetric and symmetric stretching vibrations of νs(NH3) and νas(NH3) band, respectively. AC and DC conductivities, complex dielectric permittivity ε*(ω) and complex electrical modulus M*(ω) were respectively studied as temperature and frequency functions. Moreover, the temperature dependence of the DC conductivity and relaxation frequency followed the Arrhenius relation. The frequency dependence of the real part of the AC conductivity in both phases follows the Jonscher's universal dynamic law: σTot.(ω,T) = σDC(T) + B(T) ωS(T). The close values of activation energies, obtained from the thermal behavior of the conductivity and the relaxation time confirm that the transport is through ion-hopping mechanism.

  1. The microanalysis of fixed-interval responding

    PubMed Central

    Gentry, G. David; Weiss, Bernard; Laties, Victor G.

    1983-01-01

    The fixed-interval schedule of reinforcement is one of the more widely studied schedules in the experimental analysis of behavior and is also a common baseline for behavior pharmacology. Despite many intensive studies, the controlling variables and the pattern of behavior engendered are not well understood. The present study examined the microstructure and superstructure of the behavior engendered by a fixed-interval 5- and a fixed-interval 15-minute schedule of food reinforcement in the pigeon. Analysis of performance typical of fixed-interval responding indicated that the scalloped pattern does not result from smooth acceleration in responding, but, rather, from renewed pausing early in the interval. Individual interresponse-time (IRT) analyses provided no evidence of acceleration. There was a strong indication of alternation in shorter-longer IRTs, but these shorter-longer IRTs did not occur at random, reflecting instead a sequential dependency in successive IRTs. Furthermore, early in the interval there was a high relative frequency of short IRTs. Such a pattern of early pauses and short IRTs does not suggest behavior typical of reinforced responding as exemplified by the pattern found near the end of the interval. Thus, behavior from clearly scalloped performance can be classified into three states: postreinforcement pause, interim behavior, and terminal behavior. PMID:16812324

  2. Microanalysis of fixed-interval responding

    SciTech Connect

    Gentry, G.D.; Weiss, B.; Laties, V.G.

    1983-03-01

    The fixed-interval schedule of reinforcement is one of the more widely studied schedules in the experimental analysis of behavior and is also a common baseline for behavior pharmacology. Despite many intensive studies, the controlling variables and the pattern of behavior engendered are not well understood. The present study examined the microstructure and superstructure of the behavior engendered by a fixed-interval 5- and a fixed-interval 15-minute schedule of food reinforcement in the pigeon. Analysis of performance typical of fixed-interval responding indicated that the scalloped pattern does not result from smooth acceleration in responding, but, rather, from renewed pausing early in the interval. Individual interresponse-time (IRT) analyses provided no evidence of acceleration. There was a strong indication of alternation is shorter-longer IRTs, but these shorter-longer IRTs did not occur at random, reflecting instead a sequential dependency in successive IRTs. Furthermore, early in the interval there was a high relative frequency of short IRTs. Such a pattern of early pauses and short IRTs does not suggest behavior typical of reinforced responding as exemplified by the pattern found near the end of the interval. Thus, behavior from clearly scalloped performance can be classified into three states: postreinforcement pause, interim behavior, and terminal behavior. 31 references, 11 figures, 4 tables.

  3. Bipolar control in fixed interfood intervals

    PubMed Central

    Palya, William L.

    1993-01-01

    The ability of stimuli correlated with successive periods in a fixed interfood interval to support a response that produced or removed them was examined using pigeons. The degree to which those correlated stimuli elicited directed key pecks was also obtained. Stimuli early in the interval functioned as negative reinforcers, and stimuli late in the interval functioned as positive reinforcers. Stimuli correlated with successively later portions of the second half of the interval supported successively higher rates of elicited pecking and, with the exception of the final stimulus, supported successively higher rates of stimulus production. Stimuli in successively earlier portions of the first half of the interval supported successively higher rates of correlated-stimulus removal. This effect occurred in spite of the addition of a conjoint variable-interval dependency for food. An ogive fit to the mean normalized response distributions resulted in r2s demonstrating that most of the variance in the temporal organization of the behavior was accounted for. The findings were taken to indicate that fixed interfood intervals establish bipolar control. PMID:16812702

  4. Acceleration-induced electrocardiographic interval changes.

    PubMed

    Whinnery, C C; Whinnery, J E

    1988-02-01

    The electrocardiographic intervals (PR, QRS, QT, and RR) before, during, and post +Gz stress were measured in 24 healthy male subjects undergoing +Gz centrifuge exposure. The PR and QRS intervals responded in a predictable manner, shortening during stress and returning to baseline resting values post-stress. The QT interval, however, was not observed to be dependent solely on heart rate. Bazett's formula, which was developed to correct for heart rate variability, did not adequately result in a homogeneous correction of the QT interval for each stress-related period. During +Gz stress, the QT was shortened, and the QTc prolonged. The QT interval remained shortened even though the heart rate returned to baseline (with the QTc undercorrected) in the post-stress period. The QT (QTc) interval variations probably reflect the effects of both heart rate and autonomic balance during and after +Gz stress, and may provide a measure of the prevailing autonomic (sympathetic or parasympathetic) tone existing at a given point associated with +Gz stress. These electrocardiographic interval changes define the normal response for healthy individuals. Individuals with exaggerated autonomic responses could be identified by comparing their responses to these normal responses resulting from +Gz stress.

  5. Magnetic Resonance Fingerprinting with short relaxation intervals.

    PubMed

    Amthor, Thomas; Doneva, Mariya; Koken, Peter; Sommer, Karsten; Meineke, Jakob; Börnert, Peter

    2017-09-01

    The aim of this study was to investigate a technique for improving the performance of Magnetic Resonance Fingerprinting (MRF) in repetitive sampling schemes, in particular for 3D MRF acquisition, by shortening relaxation intervals between MRF pulse train repetitions. A calculation method for MRF dictionaries adapted to short relaxation intervals and non-relaxed initial spin states is presented, based on the concept of stationary fingerprints. The method is applicable to many different k-space sampling schemes in 2D and 3D. For accuracy analysis, T1 and T2 values of a phantom are determined by single-slice Cartesian MRF for different relaxation intervals and are compared with quantitative reference measurements. The relevance of slice profile effects is also investigated in this case. To further illustrate the capabilities of the method, an application to in-vivo spiral 3D MRF measurements is demonstrated. The proposed computation method enables accurate parameter estimation even for the shortest relaxation intervals, as investigated for different sampling patterns in 2D and 3D. In 2D Cartesian measurements, we achieved a scan acceleration of more than a factor of two, while maintaining acceptable accuracy: The largest T1 values of a sample set deviated from their reference values by 0.3% (longest relaxation interval) and 2.4% (shortest relaxation interval). The largest T2 values showed systematic deviations of up to 10% for all relaxation intervals, which is discussed. The influence of slice profile effects for multislice acquisition is shown to become increasingly relevant for short relaxation intervals. In 3D spiral measurements, a scan time reduction of 36% was achieved, maintaining the quality of in-vivo T1 and T2 maps. Reducing the relaxation interval between MRF sequence repetitions using stationary fingerprint dictionaries is a feasible method to improve the scan efficiency of MRF sequences. The method enables fast implementations of 3D spatially resolved

  6. Fast transfer of crossmodal time interval training.

    PubMed

    Chen, Lihan; Zhou, Xiaolin

    2014-06-01

    Sub-second time perception is essential for many important sensory and perceptual tasks including speech perception, motion perception, motor coordination, and crossmodal interaction. This study investigates to what extent the ability to discriminate sub-second time intervals acquired in one sensory modality can be transferred to another modality. To this end, we used perceptual classification of visual Ternus display (Ternus in Psychol Forsch 7:81-136, 1926) to implicitly measure participants' interval perception in pre- and posttests and implemented an intra- or crossmodal sub-second interval discrimination training protocol in between the tests. The Ternus display elicited either an "element motion" or a "group motion" percept, depending on the inter-stimulus interval between the two visual frames. The training protocol required participants to explicitly compare the interval length between a pair of visual, auditory, or tactile stimuli with a standard interval or to implicitly perceive the length of visual, auditory, or tactile intervals by completing a non-temporal task (discrimination of auditory pitch or tactile intensity). Results showed that after fast explicit training of interval discrimination (about 15 min), participants improved their ability to categorize the visual apparent motion in Ternus displays, although the training benefits were mild for visual timing training. However, the benefits were absent for implicit interval training protocols. This finding suggests that the timing ability in one modality can be rapidly acquired and used to improve timing-related performance in another modality and that there may exist a central clock for sub-second temporal processing, although modality-specific perceptual properties may constrain the functioning of this clock.

  7. Advanced Interval Management: A Benefit Analysis

    NASA Technical Reports Server (NTRS)

    Timer, Sebastian; Peters, Mark

    2016-01-01

    This document is the final report for the NASA Langley Research Center (LaRC)- sponsored task order 'Possible Benefits for Advanced Interval Management Operations.' Under this research project, Architecture Technology Corporation performed an analysis to determine the maximum potential benefit to be gained if specific Advanced Interval Management (AIM) operations were implemented in the National Airspace System (NAS). The motivation for this research is to guide NASA decision-making on which Interval Management (IM) applications offer the most potential benefit and warrant further research.

  8. Interval arithmetic in power flow analysis

    SciTech Connect

    Wang, Z.; Alvarado, F.L. )

    1992-08-01

    The power flow is the fundamental tool for the study of power systems. The data for this problem are subject to uncertainty. This paper uses interval arithmetic to solve the power flow problem. Interval arithmetic takes into consideration the uncertainty of the nodal information, and is able to provide strict bounds for the solution to the problem: all possible solutions are included within the bounds given by interval arithmetic. Results are compared with those obtainable by Monte Carlo simulations and by the use of stochastic power flows.

  9. Learned interval time facilitates associate memory retrieval

    PubMed Central

    van de Ven, Vincent; Kochs, Sarah; Smulders, Fren; De Weerd, Peter

    2017-01-01

    The extent to which time is represented in memory remains underinvestigated. We designed a time paired associate task (TPAT) in which participants implicitly learned cue–time–target associations between cue–target pairs and specific cue–target intervals. During subsequent memory testing, participants showed increased accuracy of identifying matching cue–target pairs if the time interval during testing matched the implicitly learned interval. A control experiment showed that participants had no explicit knowledge about the cue–time associations. We suggest that “elapsed time” can act as a temporal mnemonic associate that can facilitate retrieval of events associated in memory. PMID:28298554

  10. Sampling Theory and Confidence Intervals for Effect Sizes: Using ESCI To Illustrate "Bouncing"; Confidence Intervals.

    ERIC Educational Resources Information Center

    Du, Yunfei

    This paper discusses the impact of sampling error on the construction of confidence intervals around effect sizes. Sampling error affects the location and precision of confidence intervals. Meta-analytic resampling demonstrates that confidence intervals can haphazardly bounce around the true population parameter. Special software with graphical…

  11. Interval Estimates of Multivariate Effect Sizes: Coverage and Interval Width Estimates under Variance Heterogeneity and Nonnormality

    ERIC Educational Resources Information Center

    Hess, Melinda R.; Hogarty, Kristine Y.; Ferron, John M.; Kromrey, Jeffrey D.

    2007-01-01

    Monte Carlo methods were used to examine techniques for constructing confidence intervals around multivariate effect sizes. Using interval inversion and bootstrapping methods, confidence intervals were constructed around the standard estimate of Mahalanobis distance (D[superscript 2]), two bias-adjusted estimates of D[superscript 2], and Huberty's…

  12. Activation of the TLR2-mediated downstream signaling pathways NF-κB and MAPK is responsible for B7-H3-augmented inflammatory response during S. pneumoniae infection.

    PubMed

    Chen, Xuqin; Meng, Xiangying; Foley, Niamh M; Shi, Xiaoyan; Liu, Min; Chai, Yahui; Li, Yiping; Redmond, H Paul; Wang, Jian; Wang, Jiang Huai

    2017-09-15

    It has been reported that B7-H3, a costimulatory protein, participates in the development and progression of experimental pneumococcal meningitis by amplifying the TLR2-mediated inflammatory response. This study attempted to clarify the pathway(s) of TLR2 signaling involved in B7-H3-augmented inflammatory response during S. pneumoniae infection. Murine microglial cell line N9 cells and primary murine microglial cells were infected with S. pneumoniae alone or in combination with B7-H3. Although B7-H3 stimulation failed to further enhance S. pneumoniae-upregulated mRNA and protein expression of TLR2, it strongly augmented S. pneumoniae-induced phosphorylation of NF-κB p65, MAPK p38, and ERK1/2 in both N9 cells and primary microglial cells. Notably, B7-H3 itself did not activate NF-κB p65, MAPK p38, and ERK1/2. Furthermore, deactivation of NF-κB p65, MAPK p38, and ERK1/2 with their specific inhibitors significantly attenuated B7-H3-amplified proinflammatory cytokine and chemokine release from S. pneumoniae-infected microglial cells. Importantly, blockage of NF-κB p65, MAPK p38, or ERK1/2 in vivo substantially diminished B7-H3-augmented TNF-α levels in the brain of S. pneumoniae-infected mice. These results indicate that the activation of both NF-κB and MAPKs is predominantly responsible for B7-H3-augmented inflammatory response during S. pneumoniae infection. Copyright © 2017. Published by Elsevier B.V.

  13. Interval cancers in nasopharyngeal carcinoma screening: comparing two screening intervals after a negative initial screening result.

    PubMed

    Chen, Feng; Huang, Qi-Hong; Fang, Fang; Liu, Zhi-Wei; Liu, Ke; Xie, Shang-Hang; Liu, Qing; Hong, Ming-Huang; Liao, Zhen-Er; Ye, Wei-Min; Zeng, Yi-Xin; Cao, Su-Mei

    2012-12-01

    To examine the optimal screening interval among the individuals who received a negative Epstein-Barr virus immunoglobulin A antibodies against viral capsid antigen (VCA-IgA) serum test result and who comprised the majority of the population screened for nasopharyngeal carcinoma (NPC). Screening was performed in Sihui, Guangdong, China, offering a repeated screening for participants with an initial negative test either after 4-5 years in one centre (short interval centre), or 9-10 years in another (long interval centre). The characteristics and incidence rates (IRs) of interval NPCs (defined as cases diagnosed outside the screening protocol while within the screening interval) were compared between these two centres. Standard incidence ratios (SIRs) were also calculated using the general Sihui population as the reference. Seven interval NPCs were detected in the short interval centre (IR: 17.8/10(5) person-years) and 20 in the long interval centre (IR: 20.8/10(5) person-years during the first four years and 43.5/10(5) person-years during the remaining years). The SIR in the short interval centre was 0.43 (95% confidence interval [CI]: 0.17-0.89); SIR in the long interval centre was 0.47 (95% CI: 0.17-1.02) during the first four years and 0.90 (95% CI: 0.49-1.51) during the remaining years. No aggressive interval NPC was observed in the short interval centre; four were identified in the long interval centre. The incidence of NPC, especially aggressive NPC, was low during the first few years after a negative screening; the incidence increased to the general population level afterwards. A screening interval of 4-5 years may therefore be more suitable than 9-10 years after a negative VCA-IgA test in NPC screening.

  14. A robust measure of food web intervality

    PubMed Central

    Stouffer, Daniel B.; Camacho, Juan; Amaral, Luís A. Nunes

    2006-01-01

    Intervality of a food web is related to the number of trophic dimensions characterizing the niches in a community. We introduce here a mathematically robust measure for food web intervality. It has previously been noted that empirical food webs are not strictly interval; however, upon comparison to suitable null hypotheses, we conclude that empirical food webs actually do exhibit a strong bias toward contiguity of prey, that is, toward intervality. Further, our results strongly suggest that empirically observed species and their diets can be mapped onto a single dimension. This finding validates a critical assumption in the recently proposed static niche model and provides guidance for ongoing efforts to develop dynamic models of ecosystems. PMID:17146055

  15. Intact Interval Timing in Circadian CLOCK Mutants

    PubMed Central

    Cordes, Sara; Gallistel, C. R.

    2008-01-01

    While progress has been made in determining the molecular basis for the circadian clock, the mechanism by which mammalian brains time intervals measured in seconds to minutes remains a mystery. An obvious question is whether the interval timing mechanism shares molecular machinery with the circadian timing mechanism. In the current study, we trained circadian CLOCK +/− and −/− mutant male mice in a peak-interval procedure with 10 and 20-s criteria. The mutant mice were more active than their wild-type littermates, but there were no reliable deficits in the accuracy or precision of their timing as compared with wild-type littermates. This suggests that expression of the CLOCK protein is not necessary for normal interval timing. PMID:18602902

  16. Efficient Computation Of Confidence Intervals Of Parameters

    NASA Technical Reports Server (NTRS)

    Murphy, Patrick C.

    1992-01-01

    Study focuses on obtaining efficient algorithm for estimation of confidence intervals of ML estimates. Four algorithms selected to solve associated constrained optimization problem. Hybrid algorithms, following search and gradient approaches, prove best.

  17. Application of Interval Analysis to Error Control.

    DTIC Science & Technology

    1976-09-01

    We give simple examples of ways in which interval arithmetic can be used to alert instabilities in computer algorithms , roundoff error accumulation, and even the effects of hardware inadequacies. This paper is primarily tutorial. (Author)

  18. Efficient Computation Of Confidence Intervals Of Parameters

    NASA Technical Reports Server (NTRS)

    Murphy, Patrick C.

    1992-01-01

    Study focuses on obtaining efficient algorithm for estimation of confidence intervals of ML estimates. Four algorithms selected to solve associated constrained optimization problem. Hybrid algorithms, following search and gradient approaches, prove best.

  19. A robust measure of food web intervality.

    PubMed

    Stouffer, Daniel B; Camacho, Juan; Amaral, Luís A Nunes

    2006-12-12

    Intervality of a food web is related to the number of trophic dimensions characterizing the niches in a community. We introduce here a mathematically robust measure for food web intervality. It has previously been noted that empirical food webs are not strictly interval; however, upon comparison to suitable null hypotheses, we conclude that empirical food webs actually do exhibit a strong bias toward contiguity of prey, that is, toward intervality. Further, our results strongly suggest that empirically observed species and their diets can be mapped onto a single dimension. This finding validates a critical assumption in the recently proposed static niche model and provides guidance for ongoing efforts to develop dynamic models of ecosystems.

  20. Periodicity In The Intervals Between Primes

    DTIC Science & Technology

    2015-07-02

    statistically strong periodicity is identified in the counting function giving the total number of intervals of a certain size. The nature of the periodic...positive intervals among the first n<=10^6 prime numbers as a probe of the global nature of the sequence of primes. A statistically strong periodicity is...Let x = x1, x2, . . . be an increasing sequence of real numbers which may be either finite or infinitely long. Throughout the following every bold

  1. Interval and contour processing in autism.

    PubMed

    Heaton, Pamela

    2005-12-01

    High functioning children with autism and age and intelligence matched controls participated in experiments testing perception of pitch intervals and musical contours. The finding from the interval study showed superior detection of pitch direction over small pitch distances in the autism group. On the test of contour discrimination no group differences emerged. These findings confirm earlier studies showing facilitated pitch processing and a preserved ability to represent small-scale musical structures in autism.

  2. Establishing reference intervals in the coagulation laboratory.

    PubMed

    Castellone, D D

    2017-05-01

    Obtaining a reference interval (RI) is a challenge for any laboratory and becomes more complicated in the coagulation laboratory due to testing on samples with limited stability on reagents that are poorly standardized. Reference intervals are required to be able to evaluate results in relation to a patients' hemostatic disorder. This becomes one of the most important tasks conducted in the coagulation laboratory. However, many laboratories lack the time, finances and in many cases the expertise to conduct this study. Many RI are obtained from package inserts, or from publications written by experts in lieu of laboratories conducting their own studies. An overview of validating reference intervals and options for verifying or transference of reference intervals is discussed. Based on the confidence interval and the acceptability of risk laboratories are willing to accept, coagulation laboratories have options to conduct robust studies for their RI. Data mining or global reference studies may help to provide data for age specific ranges. Pre-analytical variables and selection of healthy subjects have the largest impact on coagulation testing outcomes and need to be well controlled during the establishment of reference intervals. Laboratories have options in lieu of conducting a full validation on how to verify RI based on smaller RI studies or transference of RI after determining compatibility of the original RI study. © 2017 John Wiley & Sons Ltd.

  3. Recurrence interval analysis of trading volumes.

    PubMed

    Ren, Fei; Zhou, Wei-Xing

    2010-06-01

    We study the statistical properties of the recurrence intervals τ between successive trading volumes exceeding a certain threshold q. The recurrence interval analysis is carried out for the 20 liquid Chinese stocks covering a period from January 2000 to May 2009, and two Chinese indices from January 2003 to April 2009. Similar to the recurrence interval distribution of the price returns, the tail of the recurrence interval distribution of the trading volumes follows a power-law scaling, and the results are verified by the goodness-of-fit tests using the Kolmogorov-Smirnov (KS) statistic, the weighted KS statistic and the Cramér-von Mises criterion. The measurements of the conditional probability distribution and the detrended fluctuation function show that both short-term and long-term memory effects exist in the recurrence intervals between trading volumes. We further study the relationship between trading volumes and price returns based on the recurrence interval analysis method. It is found that large trading volumes are more likely to occur following large price returns, and the comovement between trading volumes and price returns is more pronounced for large trading volumes.

  4. [The QT interval: standardization, limits and interpretation].

    PubMed

    Ouali, S; Ben Salem, H; Gribaa, R; Kacem, S; Hammas, S; Fradi, S; Neffeti, E; Remedi, F; Boughzela, E

    2012-02-01

    Despite clinical importance of ventricular repolarisation, it remains difficult to analyse. Conventionally, quantification of the electrocardiographic ventricular repolarization is usually performed with reference to axis of the T wave and QT interval duration. A variety of factors can prolong the QT interval, such as drug effects, electrolyte imbalances, and myocardial ischemia. The biggest risk with prolongation of the QT interval is the development of torsades de pointes. Commonly accepted reference ranges for the electrocardiogram (ECG) have been in use, with little change, for many years. Populations throughout the world present several differences: age, ethnic compositions, and are exposed to different environmental factors. Recent studies have reported reference data for QT interval in healthy population and have evaluated the influence of age, gender, QRS duration and heart rate on this interval. In this review, we address several issues relative to the measurement, and interpretation of QT interval and its adjustment for rate, age, gender and QRS duration. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

  5. Probability Distribution for Flowing Interval Spacing

    SciTech Connect

    S. Kuzio

    2004-09-22

    Fracture spacing is a key hydrologic parameter in analyses of matrix diffusion. Although the individual fractures that transmit flow in the saturated zone (SZ) cannot be identified directly, it is possible to determine the fractured zones that transmit flow from flow meter survey observations. The fractured zones that transmit flow as identified through borehole flow meter surveys have been defined in this report as flowing intervals. The flowing interval spacing is measured between the midpoints of each flowing interval. The determination of flowing interval spacing is important because the flowing interval spacing parameter is a key hydrologic parameter in SZ transport modeling, which impacts the extent of matrix diffusion in the SZ volcanic matrix. The output of this report is input to the ''Saturated Zone Flow and Transport Model Abstraction'' (BSC 2004 [DIRS 170042]). Specifically, the analysis of data and development of a data distribution reported herein is used to develop the uncertainty distribution for the flowing interval spacing parameter for the SZ transport abstraction model. Figure 1-1 shows the relationship of this report to other model reports that also pertain to flow and transport in the SZ. Figure 1-1 also shows the flow of key information among the SZ reports. It should be noted that Figure 1-1 does not contain a complete representation of the data and parameter inputs and outputs of all SZ reports, nor does it show inputs external to this suite of SZ reports. Use of the developed flowing interval spacing probability distribution is subject to the limitations of the assumptions discussed in Sections 5 and 6 of this analysis report. The number of fractures in a flowing interval is not known. Therefore, the flowing intervals are assumed to be composed of one flowing zone in the transport simulations. This analysis may overestimate the flowing interval spacing because the number of fractures that contribute to a flowing interval cannot be

  6. Zincobotryogen, ZnFe3+(SO4)2(OH)ṡ7H2O: validation as a mineral species and new data

    NASA Astrophysics Data System (ADS)

    Yang, Zhuming; Giester, Gerald; Mao, Qian; Ma, Yuguang; Zhang, Di; Li, He

    2016-11-01

    Zincobotryogen occurs in the oxidation zone of the Xitieshan lead-zinc deposit, Qinghai, China. The mineral is associated with jarosite, copiapite, zincocopiapite, and quartz. The mineral forms prismatic crystals, 0.05 to 2 mm in size. It is optically positive (2Vcalc = 54.1°), with Z ‖ b and X ∧ c = 10°. The elongation is negative. The refractive indices are n α = 1.542(5), n β = 1.551(5), n γ = 1.587(5). The pleochroism scheme is X = colorless, Y = light yellow, Z = yellow. Microprobe analysis gave (in wt%): SO3 = 38.04, Al2O3 = 0.04, Fe2O3 = 18.46, ZnO = 13.75, MgO = 1.52, MnO = 1.23, H2O = 31.06 (by calculation), Total = 104.10. The simplified formula is (Zn,Mg)Fe3+(SO4)2(OH)ṡ7H2O. The mineral is monoclinic, P121/n1, a = 10.504(2), b = 17.801(4), c = 7.1263(14) Å, and β = 100.08(3)°, V = 1311.9(5) Å3, Z = 4. The strongest lines in the powder X-ray diffraction pattern d(I)(hkl) are: 8.92 (100)(110), 6.32 (77)(-101), 5.56 (23)(021), 4.08 (22)(-221),3.21 (31)(231), 3.03 (34)(032), 2.77 (22)(042). The crystal structure was refined using 2816 unique reflections to R1(F) = 0.0355 and wR2(F 2) = 0.0651. The refined formula is (Zn0.84Mg0.16)Fe3+(SO4)2(OH)ṡ7H2O. The atomic arrangement is characterized by chains with composition [Fe3+(SO4)2(OH)(H2O)]2- and 7 Å repeat distance running parallel to the c-axis. The chain links to a [MO(H2O)5] octahedron (M = Zn, Mg) and an unshared H2O molecule, and forms a larger chain building module with composition [M 2+Fe3+(SO4)2(OH)(H2O)6(H2O)]. The inter-chain module linkage involves only hydrogen bonding.

  7. Zincobotryogen, ZnFe3+(SO4)2(OH)ṡ7H2O: validation as a mineral species and new data

    NASA Astrophysics Data System (ADS)

    Yang, Zhuming; Giester, Gerald; Mao, Qian; Ma, Yuguang; Zhang, Di; Li, He

    2017-06-01

    Zincobotryogen occurs in the oxidation zone of the Xitieshan lead-zinc deposit, Qinghai, China. The mineral is associated with jarosite, copiapite, zincocopiapite, and quartz. The mineral forms prismatic crystals, 0.05 to 2 mm in size. It is optically positive (2Vcalc = 54.1°), with Z ‖ b and X ∧ c = 10°. The elongation is negative. The refractive indices are n α = 1.542(5), n β = 1.551(5), n γ = 1.587(5). The pleochroism scheme is X = colorless, Y = light yellow, Z = yellow. Microprobe analysis gave (in wt%): SO3 = 38.04, Al2O3 = 0.04, Fe2O3 = 18.46, ZnO = 13.75, MgO = 1.52, MnO = 1.23, H2O = 31.06 (by calculation), Total = 104.10. The simplified formula is (Zn,Mg)Fe3+(SO4)2(OH)ṡ7H2O. The mineral is monoclinic, P121/ n1, a = 10.504(2), b = 17.801(4), c = 7.1263(14) Å, and β = 100.08(3)°, V = 1311.9(5) Å3, Z = 4. The strongest lines in the powder X-ray diffraction pattern d(I)( hkl) are: 8.92 (100)(110), 6.32 (77)(-101), 5.56 (23)(021), 4.08 (22)(-221),3.21 (31)(231), 3.03 (34)(032), 2.77 (22)(042). The crystal structure was refined using 2816 unique reflections to R1( F) = 0.0355 and wR2( F 2) = 0.0651. The refined formula is (Zn0.84Mg0.16)Fe3+(SO4)2(OH)ṡ7H2O. The atomic arrangement is characterized by chains with composition [Fe3+(SO4)2(OH)(H2O)]2- and 7 Å repeat distance running parallel to the c-axis. The chain links to a [ MO(H2O)5] octahedron ( M = Zn, Mg) and an unshared H2O molecule, and forms a larger chain building module with composition [ M 2+Fe3+(SO4)2(OH)(H2O)6(H2O)]. The inter-chain module linkage involves only hydrogen bonding.

  8. Analysis of regression confidence intervals and Bayesian credible intervals for uncertainty quantification

    NASA Astrophysics Data System (ADS)

    Lu, Dan; Ye, Ming; Hill, Mary C.

    2012-09-01

    Confidence intervals based on classical regression theories augmented to include prior information and credible intervals based on Bayesian theories are conceptually different ways to quantify parametric and predictive uncertainties. Because both confidence and credible intervals are used in environmental modeling, we seek to understand their differences and similarities. This is of interest in part because calculating confidence intervals typically requires tens to thousands of model runs, while Bayesian credible intervals typically require tens of thousands to millions of model runs. Given multi-Gaussian distributed observation errors, our theoretical analysis shows that, for linear or linearized-nonlinear models, confidence and credible intervals are always numerically identical when consistent prior information is used. For nonlinear models, nonlinear confidence and credible intervals can be numerically identical if parameter confidence regions defined using the approximate likelihood method and parameter credible regions estimated using Markov chain Monte Carlo realizations are numerically identical and predictions are a smooth, monotonic function of the parameters. Both occur if intrinsic model nonlinearity is small. While the conditions of Gaussian errors and small intrinsic model nonlinearity are violated by many environmental models, heuristic tests using analytical and numerical models suggest that linear and nonlinear confidence intervals can be useful approximations of uncertainty even under significantly nonideal conditions. In the context of epistemic model error for a complex synthetic nonlinear groundwater problem, the linear and nonlinear confidence and credible intervals for individual models performed similarly enough to indicate that the computationally frugal confidence intervals can be useful in many circumstances. Experiences with these groundwater models are expected to be broadly applicable to many environmental models. We suggest that for

  9. Interpregnancy interval and risk of autistic disorder.

    PubMed

    Gunnes, Nina; Surén, Pål; Bresnahan, Michaeline; Hornig, Mady; Lie, Kari Kveim; Lipkin, W Ian; Magnus, Per; Nilsen, Roy Miodini; Reichborn-Kjennerud, Ted; Schjølberg, Synnve; Susser, Ezra Saul; Øyen, Anne-Siri; Stoltenberg, Camilla

    2013-11-01

    A recent California study reported increased risk of autistic disorder in children conceived within a year after the birth of a sibling. We assessed the association between interpregnancy interval and risk of autistic disorder using nationwide registry data on pairs of singleton full siblings born in Norway. We defined interpregnancy interval as the time from birth of the first-born child to conception of the second-born child in a sibship. The outcome of interest was autistic disorder in the second-born child. Analyses were restricted to sibships in which the second-born child was born in 1990-2004. Odds ratios (ORs) were estimated by fitting ordinary logistic models and logistic generalized additive models. The study sample included 223,476 singleton full-sibling pairs. In sibships with interpregnancy intervals <9 months, 0.25% of the second-born children had autistic disorder, compared with 0.13% in the reference category (≥ 36 months). For interpregnancy intervals shorter than 9 months, the adjusted OR of autistic disorder in the second-born child was 2.18 (95% confidence interval 1.42-3.26). The risk of autistic disorder in the second-born child was also increased for interpregnancy intervals of 9-11 months in the adjusted analysis (OR = 1.71 [95% CI = 1.07-2.64]). Consistent with a previous report from California, interpregnancy intervals shorter than 1 year were associated with increased risk of autistic disorder in the second-born child. A possible explanation is depletion of micronutrients in mothers with closely spaced pregnancies.

  10. Single-Nucleotide Polymorphisms in the Whole-Genome Sequence Data of Shiga Toxin-Producing Escherichia coli O157:H7/H- Strains by Cultivation.

    PubMed

    Yokoyama, Eiji; Hirai, Shinichiro; Ishige, Taichiro; Murakami, Satoshi

    2017-04-01

    Nine Shiga toxin-producing Escherichia coli O157:H7/H- (O157) strains were serially cultured three times on LB agar plates. After each sub-culture, five colonies were picked for DNA isolation and whole genome sequence (WGS) analysis. After exclusion of possible recombination-related SNPs, 11, 9, and 34 single-nucleotide polymorphisms (SNPs) were detected in genes in the backbone, O-island, and mobile elements gene categories. This suggested that those SNPs due to cultivation could influence the threshold value set for molecular epidemiological studies of O157. Significant differences were observed by the Kruskal-Wallis test (P < 0.01) when the number of the SNPs in a strain was compared to that in other strains. This indicated that a specific number of strains could be used for setting the threshold value in molecular epidemiological studies. Due to cultivation, the SNPs were also detected in genes in a few core genome or core gene sets, suggesting that those SNPs could affect studies of phylogeny as well as molecular epidemiology. To improve the accuracy of phylogenetic and molecular epidemiological studies, genes in which the SNPs have arisen due to cultivation should be excluded from WGS data.

  11. Anti-proliferative activity of 2,6-dichloro-9- or 7-(ethoxycarbonylmethyl)-9H- or 7H-purines against several human solid tumour cell lines.

    PubMed

    Morales, Fátima; Ramírez, Alberto; Conejo-García, Ana; Morata, Cynthia; Marchal, Juan A; Campos, Joaquín M

    2014-04-09

    As leads we took several benzo-fused seven- and six-membered scaffolds linked to the pyrimidine or purine moieties with notable anti-proliferative activity against human breast, colon and melanoma cancerous cell lines. We then decided to maintain the double-ringed nitrogenous bases and change the other components to the ethyl acetate moiety. This way six purine and two 5-fluorouracil derivatives were obtained and evaluated against the MCF-7, HCT-116, A-375 and G-361 cancer cell lines. Two QSARs are obtained between the anti-proliferative IC₅₀ values for compounds 26-33 and the clog P against the melanoma cell lines A-375 and G-361. Our results show that two of the analogues [ethyl 2-(2,6-dichloro-9H- or 7H-purine-9- or 7-yl)acetates (30 and 33, respectively)] are potent cytotoxic agents against all the tumour cell lines assayed, showing single-digit micromolar IC₅₀ values. This exemplifies the potential of our previously reported purine compounds to qualify as lead structures for medicinal chemistry campaigns, affording simplified analogues easy to synthesize and with a noteworthy bioactivity. The selective activity of 30 and 33 against the melanoma cell line A-375, via apoptosis, supposes a great advantage for a future therapeutic use. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  12. [Determination of antimycobacterial activities of fluoroquinolones against clinical isolates of Mycobacterium tuberculosis: comparative determination with egg-based Ogawa and agar-based Middlebrook 7H10 media].

    PubMed

    Yamane, N; Chilima, B Z; Tosaka, M; Okazawa, Y; Tanno, K

    1996-08-01

    The minimum inhibitory concentrations (MICs) to the fluoroquinolones, ofloxacin (OFLX), ciprofloxacin (CPFX), sparfloxacin (SPFX), norfloxacin (NFLX), balofloxacin (BLFX) and CS-940, were determined in 100 clinical isolates of Mycobacterium tuberculosis. The MICs were determined with 1% egg-based Ogawa or agar-based Middlebrook 7H10 and each of them supplemented with oxidation-reduction color dye, 2,3-diphenyl-5-thienyl-(2)-tetrazolium chloride (STC) by using the microculture technique. The MICs determined with Ogawa medium were approximately two- to four-fold higher when compared to those determined with Middlebrook agar medium. The supplement with STC slightly increased the MICs, probably as a result of easily recognizing small initial colonies. Among the six fluoroquinolones, CS-940 and SPFX showed the greatest antimycobacterial activities with inhibition of 50% of all the isolates at the concentrations between 0.25 to 0.5 microgram/ml. OFLX, CPFX and BLFX followed in potency at 0.5 to 2.0 micrograms /ml. NFLX was less potent requiring 8 to 16 micrograms/ml to inhibit 50% of the isolates.

  13. Characterization of the sulphate mineral amarantite - Fe2(3+)(SO4)O·7H2O using infrared, Raman spectroscopy and thermogravimetry.

    PubMed

    Frost, Ray L; López, Andrés; Scholz, Ricardo; Xi, Yunfei; da Silveira, Aléssio J; Lima, Rosa Malena Fernandes

    2013-10-01

    The mineral amarantite Fe2(3+)(SO4)O·7H2O has been studied using a combination of techniques including thermogravimetry, electron probe analyses and vibrational spectroscopy. Thermal analysis shows decomposition steps at 77.63, 192.2, 550 and 641.4°C. The Raman spectrum of amarantite is dominated by an intense band at 1017 cm(-1) assigned to the SO4(2-) ν1 symmetric stretching mode. Raman bands at 1039, 1054, 1098, 1131, 1195 and 1233 cm(-1) are attributed to the SO4(2-) ν3 antisymmetric stretching modes. Very intense Raman band is observed at 409 cm(-1) with shoulder bands at 399, 451 and 491 cm(-1) are assigned to the ν2 bending modes. A series of low intensity Raman bands are found at 543, 602, 622 and 650 cm(-1) are assigned to the ν4 bending modes. A very sharp Raman band at 3529 cm(-1) is assigned to the stretching vibration of OH units. A series of Raman bands observed at 3025, 3089, 3227, 3340, 3401 and 3480 cm(-1) are assigned to water bands. Vibrational spectroscopy enables aspects of the molecular structure of the mineral amarantite to be ascertained.

  14. A Binuclear Zinc Interaction Fold Discovered in the Homodimer of Alzheimer's Amyloid-β Fragment with Taiwanese Mutation D7H.

    PubMed

    Polshakov, Vladimir I; Mantsyzov, Alexey B; Kozin, Sergey A; Adzhubei, Alexei A; Zhokhov, Sergey S; van Beek, Wouter; Kulikova, Alexandra A; Indeykina, Maria I; Mitkevich, Vladimir A; Makarov, Alexander A

    2017-06-01

    Zinc-induced oligomerization of amyloid-β peptide (Aβ) produces potentially pathogenic agents of Alzheimer's disease. Mutations and modifications in the metal binding domain 1-16 of Aβ peptide crucially affect its zinc-induced oligomerization by changing intermolecular zinc mediated interface. The 3D structure of this interface appearing in a range of Aβ species is a prospective drug target for disease modifying therapy. Using NMR spectroscopy, EXAFS spectroscopy, mass spectrometry, and isothermal titration calorimetry the interaction of zinc ions with Aβ fragments 1-7 and 1-10 carrying familial Taiwanese mutation D7H was studied. Zinc ions induce formation of a stable homodimer formed by the two peptide chains fastened by two zinc ions and stacking interactions of imidazole rings. A binuclear zinc interaction fold in the dimer structure was discovered. It can be used for designing zinc-regulated proteins and zinc-mediated self-assembling peptides. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Serological evidence of H7, H5 and H9 avian influenza virus co-infection among herons in a city park in Jiangxi, China

    PubMed Central

    Wang, Guirong; Zhang, Tao; Li, Xiaowen; Jiang, Zhiben; Jiang, Qian; Chen, Quanjiao; Tu, Xiaobin; Chen, Ze; Chang, Jianyu; Li, Laixing; Xu, Bing

    2014-01-01

    Extensive surveillance of influenza A viruses in different avian species is critical for understanding its transmission. Here, a breeding colony of Little Egrets and Black-crowned Night Herons was monitored both serologically and virologically in a city park of Jiangxi in 2009. A portion of herons had antibodies against H7 (52%), H5 (55%) and H9 (6%) subtype avian influenza virus (AIV) in egg yolk samples, and 45% had antibodies against different AIV serotypes (H5, H7 or H9) simultaneously. Greater numbers of samples with anti-AIV H5N1 recombination-4 (Re-4, clade 7) antibodies were measured compared with those containing anti-H5N1 Re-1 (clade 0) and Re-5 (clade 2.3.4) antibodies. Eight strains of H5 and 9 strains of H9 were isolated from poultry of nearby markets. These results indicate wild birds are at risk from infection and co-infection with H7, H5, and H9 subtypes. Investigation of wild bird infection might provide an early warning sign of potential novel AIVs circulating in the nearby poultry industry and even in human society. PMID:25242001

  16. Passenger evaluation of the optimum balance between fresh air supply and humidity from 7-h exposures in a simulated aircraft cabin.

    PubMed

    Strøm-Tejsen, P; Wyon, D P; Lagercrantz, L; Fang, L

    2007-04-01

    A 21-seat section of an aircraft cabin with realistic pollution sources was built inside a climate chamber capable of providing fresh outside air at very low humidity. Maintaining a constant 200 l/s rate of total air supply, i.e. recirculated and make-up air, to the cabin, experiments simulating 7-h transatlantic flights were carried out at four rates of fresh outside air supply--1.4, 3.3, 4.7, and 9.4 l/s per person (3, 7, 10, and 20 cfm/person)--resulting in humidity levels, ranging from 7% to 28% relative humidity (RH). Four groups of 16-18 subjects acted as passengers and crew and were each exposed to the four simulated flight conditions. During each flight the subjects completed questionnaires three times to provide subjective ratings of air quality and of symptoms commonly experienced during flight. Physiological tests of eye, nose, and skin function were administered twice. Analysis of the subjective assessments showed that increasing RH in the aircraft cabin to 28% RH by reducing outside flow to 1.4 l/s per person did not reduce the intensity of the symptoms that are typical of the aircraft cabin environment. On the contrary, it intensified complaints of headache, dizziness, and claustrophobia, due to the increased level of contaminants. The investigation shows that increasing aircraft cabin humidity by decreasing the ventilation flow rate of fresh outside air would not decrease reports of discomfort made by cabin occupants.

  17. Comparison of the antidepressive effects of trans-resveratrol and 5-methoxy-7H-dibenzo[de,h]quinolin-7-one.

    PubMed

    López, Miriam Cebey; Fontenla, José A; Uriarte, Eugenio; Santana, Lourdes; Sobarzo-Sánchez, Eduardo

    2014-01-01

    In this study we evaluate the in vivo antidepressant effect of a natural phenolic compound, trans-resveratrol, and a synthetic derivative from Menispermum dauricum DC (Menispermaceae) 5-methoxy-7H-dibenzo[de,h]quinolin-7- one known as 5-methoxyoxoisoaporphine (OXO 4). The antidepressant-like effect of trans-resveratrol and OXO 4 were evaluated through a Forced Swimming Test (FST), and they were compared with reference antidepressants: imipramine, desipramine, nomifensine, bupropion, nisoxetine, citalopram and moclobemide. Trans-resveratrol (10 mg/kg, intraperitoneally i.p. significantly decreased the immobility time in mouse model of despair test (69.03 ± 8.74 sec) p<0.05, as well as OXO 4 (1mg/kg, i.p. (60.92 ± 11.37 sec); p<0.05. We also evaluate the OXO 4 at 15, 30 and 45 min. affording the mayor reduction at 30 minutes after the administration. Thus, our results suggest that OXO 4 has a great antidepressant effect non-reported for this type of isoquinoline alkaloids. The pharmaceutical use of OXO 4 in the treatment of depressive disorders is a therapeutic alternative to be studied.

  18. PTR-MS assessment of photocatalytic and sorption-based purification of recirculated cabin air during simulated 7-h flights with high passenger density.

    PubMed

    Wisthaler, Armin; Strøm-Tejsen, Peter; Fang, Lei; Arnaud, Timothy J; Hansel, Armin; Märk, Tilmann D; Wyon, David P

    2007-01-01

    Four different air purification conditions were established in a simulated 3-row 21-seat section of an aircraft cabin: no air purifier; a photocatalytic oxidation unit with an adsorptive prefilter; a second photocatalytic unit with an adsorptive prefilter; and a two-stage sorption-based air filter (gas-phase absorption and adsorption). The air purifiers placed in the cabin air recirculation system were commercial prototypes developed for use in aircraft cabin systems. The four conditions were established in balanced order on 4 successive days of each of 4 successive weeks during simulated 7-h flights with 17 occupants. Proton-transfer reaction mass spectrometry was used to assess organic gas-phase pollutants and the performance of each air purifier. The concentration of most organic pollutants present in aircraft cabin air was efficiently reduced by all three units. The photocatalytic units were found to incompletely oxidize ethanol released by the wet wipes commonly supplied with airline mealsto produce unacceptably high levels of acetaldehyde and formaldehyde.

  19. Serological evidence of H7, H5 and H9 avian influenza virus co-infection among herons in a city park in Jiangxi, China.

    PubMed

    Wang, Guirong; Zhang, Tao; Li, Xiaowen; Jiang, Zhiben; Jiang, Qian; Chen, Quanjiao; Tu, Xiaobin; Chen, Ze; Chang, Jianyu; Li, Laixing; Xu, Bing

    2014-09-22

    Extensive surveillance of influenza A viruses in different avian species is critical for understanding its transmission. Here, a breeding colony of Little Egrets and Black-crowned Night Herons was monitored both serologically and virologically in a city park of Jiangxi in 2009. A portion of herons had antibodies against H7 (52%), H5 (55%) and H9 (6%) subtype avian influenza virus (AIV) in egg yolk samples, and 45% had antibodies against different AIV serotypes (H5, H7 or H9) simultaneously. Greater numbers of samples with anti-AIV H5N1 recombination-4 (Re-4, clade 7) antibodies were measured compared with those containing anti-H5N1 Re-1 (clade 0) and Re-5 (clade 2.3.4) antibodies. Eight strains of H5 and 9 strains of H9 were isolated from poultry of nearby markets. These results indicate wild birds are at risk from infection and co-infection with H7, H5, and H9 subtypes. Investigation of wild bird infection might provide an early warning sign of potential novel AIVs circulating in the nearby poultry industry and even in human society.

  20. Genetic analyses of a seasonal interval timer.

    PubMed

    Prendergast, Brian J; Renstrom, Randall A; Nelson, Randy J

    2004-08-01

    Seasonal clocks (e.g., circannual clocks, seasonal interval timers) permit anticipation of regularly occurring environmental events by timing the onset of seasonal transitions in reproduction, metabolism, and behavior. Implicit in the concept that seasonal clocks reflect adaptations to the local environment is the unexamined assumption that heritable genetic variance exists in the critical features of such clocks, namely, their temporal properties. These experiments quantified the intraspecific variance in, and heritability of, the photorefractoriness interval timer in Siberian hamsters (Phodopus sungorus), a seasonal clock that provides temporal information to mechanisms that regulate seasonal transitions in body weight. Twenty-seven families consisting of 54 parents and 109 offspring were raised in a long-day photoperiod and transferred as adults to an inhibitory photoperiod (continuous darkness; DD). Weekly body weight measurements permitted specification of the interval of responsiveness to DD, a reflection of the duration of the interval timer, in each individual. Body weights of males and females decreased after exposure to DD, but 3 to 5 months later, somatic recrudescence occurred, indicative of photorefractoriness to DD. The interval timer was approximately 5 weeks longer and twice as variable in females relative to males. Analyses of variance of full siblings revealed an overall intraclass correlation of 0.71 +/- 0.04 (0.51 +/- 0.10 for male offspring and 0.80 +/- 0.06 for female offspring), suggesting a significant family resemblance in the duration of interval timers. Parent-offspring regression analyses yielded an overall heritability estimate of 0.61 +/- 0.2; h(2) estimates from parent-offspring regression analyses were significant for female offspring (0.91 +/- 0.4) but not for male offspring (0.35 +/- 0.2), indicating strong additive genetic components for this trait, primarily in females. In nature, individual differences, both within and between

  1. Heart rate dependency of JT interval sections.

    PubMed

    Hnatkova, Katerina; Johannesen, Lars; Vicente, Jose; Malik, Marek

    2017-08-09

    Little experience exists with the heart rate correction of J-Tpeak and Tpeak-Tend intervals. In a population of 176 female and 176 male healthy subjects aged 32.3±9.8 and 33.1±8.4years, respectively, curve-linear and linear relationship to heart rate was investigated for different sections of the JT interval defined by the proportions of the area under the vector magnitude of the reconstructed 3D vectorcardiographic loop. The duration of the JT sub-section between approximately just before the T peak and almost the T end was found heart rate independent. Most of the JT heart rate dependency relates to the beginning of the interval. The duration of the terminal T wave tail is only weakly heart rate dependent. The Tpeak-Tend is only minimally heart rate dependent and in studies not showing substantial heart rate changes does not need to be heart rate corrected. For any correction formula that has linear additive properties, heart rate correction of JT and JTpeak intervals is practically the same as of the QT interval. However, this does not apply to the formulas in the form of Int/RR(a) since they do not have linear additive properties. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Sunspot Time Series: Passive and Active Intervals

    NASA Astrophysics Data System (ADS)

    Zięba, S.; Nieckarz, Z.

    2014-07-01

    Solar activity slowly and irregularly decreases from the first spotless day (FSD) in the declining phase of the old sunspot cycle and systematically, but also in an irregular way, increases to the new cycle maximum after the last spotless day (LSD). The time interval between the first and the last spotless day can be called the passive interval (PI), while the time interval from the last spotless day to the first one after the new cycle maximum is the related active interval (AI). Minima of solar cycles are inside PIs, while maxima are inside AIs. In this article, we study the properties of passive and active intervals to determine the relation between them. We have found that some properties of PIs, and related AIs, differ significantly between two group of solar cycles; this has allowed us to classify Cycles 8 - 15 as passive cycles, and Cycles 17 - 23 as active ones. We conclude that the solar activity in the PI declining phase (a descending phase of the previous cycle) determines the strength of the approaching maximum in the case of active cycles, while the activity of the PI rising phase (a phase of the ongoing cycle early growth) determines the strength of passive cycles. This can have implications for solar dynamo models. Our approach indicates the important role of solar activity during the declining and the rising phases of the solar-cycle minimum.

  3. Musical intervals and relative pitch: frequency resolution, not interval resolution, is special.

    PubMed

    McDermott, Josh H; Keebler, Michael V; Micheyl, Christophe; Oxenham, Andrew J

    2010-10-01

    Pitch intervals are central to most musical systems, which utilize pitch at the expense of other acoustic dimensions. It seemed plausible that pitch might uniquely permit precise perception of the interval separating two sounds, as this could help explain its importance in music. To explore this notion, a simple discrimination task was used to measure the precision of interval perception for the auditory dimensions of pitch, brightness, and loudness. Interval thresholds were then expressed in units of just-noticeable differences for each dimension, to enable comparison across dimensions. Contrary to expectation, when expressed in these common units, interval acuity was actually worse for pitch than for loudness or brightness. This likely indicates that the perceptual dimension of pitch is unusual not for interval perception per se, but rather for the basic frequency resolution it supports. The ubiquity of pitch in music may be due in part to this fine-grained basic resolution.

  4. DETERMINING TITAN'S SPIN STATE FROM CASSINI RADAR IMAGES

    SciTech Connect

    Stiles, Bryan W.; Hensley, Scott; Ostro, Steven J.; Callahan, Philip S.; Gim, Yonggyu; Hamilton, Gary; Johnson, William T. K.; West, Richard D.; Kirk, Randolph L.; Lee, Ella; Lorenz, Ralph D.; Allison, Michael D.; Iess, Luciano; Del Marmo, Paolo Perci

    2008-05-15

    For some 19 areas of Titan's surface, the Cassini RADAR instrument has obtained synthetic aperture radar (SAR) images during two different flybys. The time interval between flybys varies from several weeks to two years. We have used the apparent misregistration (by 10-30 km) of features between separate flybys to construct a refined model of Titan's spin state, estimating six parameters: north pole right ascension and declination, spin rate, and these quantities' first time derivatives We determine a pole location with right ascension of 39.48 degrees and declination of 83.43 degrees corresponding to a 0.3 degree obliquity. We determine the spin rate to be 22.5781 deg day{sup -1} or 0.001 deg day{sup -1} faster than the synchronous spin rate. Our estimated corrections to the pole and spin rate exceed their corresponding standard errors by factors of 80 and 8, respectively. We also found that the rate of change in the pole right ascension is -30 deg century{sup -1}, ten times faster than right ascension rate of change for the orbit normal. The spin rate is increasing at a rate of 0.05 deg day{sup -1} per century. We observed no significant change in pole declination over the period for which we have data. Applying our pole correction reduces the feature misregistration from tens of km to 3 km. Applying the spin rate and derivative corrections further reduces the misregistration to 1.2 km.

  5. Determining titan's spin state from cassini radar images

    USGS Publications Warehouse

    Stiles, B.W.; Kirk, R.L.; Lorenz, R.D.; Hensley, S.; Lee, E.; Ostro, S.J.; Allison, M.D.; Callahan, P.S.; Gim, Y.; Iess, L.; Del Marmo, P.P.; Hamilton, G.; Johnson, W.T.K.; West, R.D.

    2008-01-01

    For some 19 areas of Titan's surface, the Cassini RADAR instrument has obtained synthetic aperture radar (SAR) images during two different flybys. The time interval between flybys varies from several weeks to two years. We have used the apparent misregistration (by 10-30 km) of features between separate flybys to construct a refined model of Titan's spin state, estimating six parameters: north pole right ascension and declination, spin rate, and these quantities' first time derivatives We determine a pole location with right ascension of 39.48 degrees and declination of 83.43 degrees corresponding to a 0.3 degree obliquity. We determine the spin rate to be 22.5781 deg day -1 or 0.001 deg day-1 faster than the synchronous spin rate. Our estimated corrections to the pole and spin rate exceed their corresponding standard errors by factors of 80 and 8, respectively. We also found that the rate of change in the pole right ascension is -30 deg century-1, ten times faster than right ascension rate of change for the orbit normal. The spin rate is increasing at a rate of 0.05 deg day -1 per century. We observed no significant change in pole declination over the period for which we have data. Applying our pole correction reduces the feature misregistration from tens of km to 3 km. Applying the spin rate and derivative corrections further reduces the misregistration to 1.2 km. ?? 2008. The American Astronomical Society. All rights reserved.

  6. Perceptual interference decays over short unfilled intervals.

    PubMed

    Schulkind, M D

    2000-09-01

    The perceptual interference effect refers to the fact that object identification is directly related to the amount of information available at initial exposure. The present article investigated whether perceptual interference would dissipate when a short, unfilled interval was introduced between exposures to a degraded object. Across three experiments using both musical and pictorial stimuli, identification performance increased directly with the length of the unfilled interval. Consequently, significant perceptual interference was obtained only when the interval between exposures was relatively short (< 500 msec for melodies; < 300 msec for pictures). These results are consistent with explanations that attribute perceptual interference to increased perceptual noise created by exposures to highly degraded objects. The data also suggest that perceptual interference is mediated by systems that are not consciously controlled by the subject and that perceptual interference in the visual domain decays more rapidly than perceptual interference in the auditory domain.

  7. Intervality and coherence in complex networks

    NASA Astrophysics Data System (ADS)

    Domínguez-García, Virginia; Johnson, Samuel; Muñoz, Miguel A.

    2016-06-01

    Food webs—networks of predators and prey—have long been known to exhibit "intervality": species can generally be ordered along a single axis in such a way that the prey of any given predator tend to lie on unbroken compact intervals. Although the meaning of this axis—usually identified with a "niche" dimension—has remained a mystery, it is assumed to lie at the basis of the highly non-trivial structure of food webs. With this in mind, most trophic network modelling has for decades been based on assigning species a niche value by hand. However, we argue here that intervality should not be considered the cause but rather a consequence of food-web structure. First, analysing a set of 46 empirical food webs, we find that they also exhibit predator intervality: the predators of any given species are as likely to be contiguous as the prey are, but in a different ordering. Furthermore, this property is not exclusive of trophic networks: several networks of genes, neurons, metabolites, cellular machines, airports, and words are found to be approximately as interval as food webs. We go on to show that a simple model of food-web assembly which does not make use of a niche axis can nevertheless generate significant intervality. Therefore, the niche dimension (in the sense used for food-web modelling) could in fact be the consequence of other, more fundamental structural traits. We conclude that a new approach to food-web modelling is required for a deeper understanding of ecosystem assembly, structure, and function, and propose that certain topological features thought to be specific of food webs are in fact common to many complex networks.

  8. Intervality and coherence in complex networks.

    PubMed

    Domínguez-García, Virginia; Johnson, Samuel; Muñoz, Miguel A

    2016-06-01

    Food webs-networks of predators and prey-have long been known to exhibit "intervality": species can generally be ordered along a single axis in such a way that the prey of any given predator tend to lie on unbroken compact intervals. Although the meaning of this axis-usually identified with a "niche" dimension-has remained a mystery, it is assumed to lie at the basis of the highly non-trivial structure of food webs. With this in mind, most trophic network modelling has for decades been based on assigning species a niche value by hand. However, we argue here that intervality should not be considered the cause but rather a consequence of food-web structure. First, analysing a set of 46 empirical food webs, we find that they also exhibit predator intervality: the predators of any given species are as likely to be contiguous as the prey are, but in a different ordering. Furthermore, this property is not exclusive of trophic networks: several networks of genes, neurons, metabolites, cellular machines, airports, and words are found to be approximately as interval as food webs. We go on to show that a simple model of food-web assembly which does not make use of a niche axis can nevertheless generate significant intervality. Therefore, the niche dimension (in the sense used for food-web modelling) could in fact be the consequence of other, more fundamental structural traits. We conclude that a new approach to food-web modelling is required for a deeper understanding of ecosystem assembly, structure, and function, and propose that certain topological features thought to be specific of food webs are in fact common to many complex networks.

  9. Interval Estimation of Seismic Hazard Parameters

    NASA Astrophysics Data System (ADS)

    Orlecka-Sikora, Beata; Lasocki, Stanislaw

    2017-03-01

    The paper considers Poisson temporal occurrence of earthquakes and presents a way to integrate uncertainties of the estimates of mean activity rate and magnitude cumulative distribution function in the interval estimation of the most widely used seismic hazard functions, such as the exceedance probability and the mean return period. The proposed algorithm can be used either when the Gutenberg-Richter model of magnitude distribution is accepted or when the nonparametric estimation is in use. When the Gutenberg-Richter model of magnitude distribution is used the interval estimation of its parameters is based on the asymptotic normality of the maximum likelihood estimator. When the nonparametric kernel estimation of magnitude distribution is used, we propose the iterated bias corrected and accelerated method for interval estimation based on the smoothed bootstrap and second-order bootstrap samples. The changes resulted from the integrated approach in the interval estimation of the seismic hazard functions with respect to the approach, which neglects the uncertainty of the mean activity rate estimates have been studied using Monte Carlo simulations and two real dataset examples. The results indicate that the uncertainty of mean activity rate affects significantly the interval estimates of hazard functions only when the product of activity rate and the time period, for which the hazard is estimated, is no more than 5.0. When this product becomes greater than 5.0, the impact of the uncertainty of cumulative distribution function of magnitude dominates the impact of the uncertainty of mean activity rate in the aggregated uncertainty of the hazard functions. Following, the interval estimates with and without inclusion of the uncertainty of mean activity rate converge. The presented algorithm is generic and can be applied also to capture the propagation of uncertainty of estimates, which are parameters of a multiparameter function, onto this function.

  10. B7-H4 expression is elevated in human U251 glioma stem-like cells and is inducible in monocytes cultured with U251 stem-like cell conditioned medium.

    PubMed

    Mo, Lian-Jie; Ye, Hong-Xing; Mao, Ying; Yao, Yu; Zhang, Jian-Min

    2013-12-01

    Previous studies indicated that B7-H4, the youngest B7 family, negatively regulates T cell-mediated immunity and is significantly overexpressed in many human tumors. Tumor stem cells are purported to play a role in tumor renewal and resistance to radiation and chemotherapy. However, the link between B7-H4 and tumor stem cells is unclear. In this study, we investigated B7-H4 expression in the medium of human glioma U251 cell cultures. Immunofluorescence results showed that U251 cells cultured in serum-free medium (supplemented with 2% B27, 20 ng/mL epidermal growth factor, 20 ng/mL basic fibroblast growth factor) maintained stem-like cell characteristics, including expression of stem cell marker CD133 and the neural progenitor cell markers nestin and SOX2. In contrast, U251 cells cultured in serum-containing medium highly expressed differentiation marker glial fibrillary acidic protein. Flow cytometry analysis showed serum-free medium-cultured U251 cells expressed higher intracellular B7-H4 than serum-containing medium-cultured U251 cells (24%-35% vs. 8%-11%, P < 0.001). Immunofluorescence in purified monocytes from normal human peripheral blood mononuclear cells revealed moderate expression of B7-H4 after stimulation with conditioned medium from U251 cells cultured in serum-containing medium. Moreover, conditioned medium from U251 stem-like cells had a significant stimulation effect on B7-H4 expression compared with serum-containing conditioned medium (P < 0.01). Negative costimulatory molecule B7-H4 was preferentially expressed in U251 stem-like cells, and conditioned medium from these cells more effectively induced monocytes to express B7-H4 than conditioned medium from U251 cells cultured in the presence of serum. Our results show that U251 stem-like cells may play a more crucial role in tumor immunoloregulation with high expression of B7-H4.

  11. Children's artistic responses to musical intervals.

    PubMed

    Smith, L D; Williams, R N

    1999-01-01

    In one experiment, White South African boys drew pictures in response to four musical intervals. In the second, the subjects were of both sexes and drawn from White, urban Black, and rural Black populations. Six intervals were used. Drawing content was similar cross-culturally. Consonances were perceived as generally positive; dissonances, generally negative. There was also an activity dimension. Children in a lower grade drew more concrete pictures than did those in a higher grade, regardless of age. Even young listeners were fairly consistent in their responses. This suggests that perception of musical meaning is a universal rather than culturally based phenomenon.

  12. Amniotic fluid stem cells provide considerable advantages in epidermal regeneration: B7H4 creates a moderate inflammation microenvironment to promote wound repair

    PubMed Central

    Sun, Qing; Li, Fang; Li, Hong; Chen, Rui-Hua; Gu, Yan-Zheng; Chen, Ying; Liang, Han-Si; You, Xin-Ran; Ding, Si-Si; Gao, Ling; Wang, Yun-Liang; Qin, Ming-De; Zhang, Xue-Guang

    2015-01-01

    The current treatments for severe skin injury all involve skin grafting. However, there is a worldwide shortage of donor skin tissue. In this study, we examined the advantages of using human amniotic fluid stem (hAFS) cells in skin wound healing. In vitro, hAFS cells differentiate into keratinocytes (termed hAFS-K). Like keratinocytes, hAFS-K cells express the markers K5, K14, K10 and involucrin; display typical cellular structure, including a tonofibril-rich cytoplasm; and construct a completely pluristratified epithelium in 3D culture. In vivo, in a mouse excisional wound model, GFP-positive hAFS cells participate in wound repair. Co-localization of GFP/K14 and GFP/K10 in the repaired epidermis demonstrated that hAFS cells can differentiate into keratinocytes. Real-time PCR results confirmed that hAFS cells can initiate and promote early-stage repair of skin damage. During wound repair, hAFS cells did not directly secrete repair-related factors, such as bFGF, VEGF, CXCL12, TGF-β1 and KGF, and provided a moderate inflammation reaction with lower expression of IL-1β, IL-6, TNF-α, Cox2 and Mac3. In hAFS cells, the negative co-stimulatory molecule B7H4 regulates low immunogenicity, which can provide a modest inflammatory reaction microenvironment for wound repair. Furthermore, with their uniquely high proliferation rate, hAFS cells offer a promising alternative for epidermal regeneration. PMID:26101181

  13. A vibrational spectroscopic study of the borate mineral ezcurrite Na4B10O17·7H2O - Implications for the molecular structure

    NASA Astrophysics Data System (ADS)

    Frost, Ray L.; López, Andrés; Theiss, Frederick L.; Scholz, Ricardo; Belotti, Fernanda M.

    2014-07-01

    We have studied the boron containing mineral ezcurrite Na4B10O17·7H2O using electron microscopy and vibrational spectroscopy. Both tetrahedral and trigonal boron units are observed. The nominal resolution of the Raman spectrometer is of the order of 2 cm-1 and as such is sufficient enough to identify separate bands for the stretching bands of the two boron isotopes. The Raman band at 1037 cm-1 is assigned to BO stretching vibration. Raman bands at 1129, 1163, 1193 cm-1 are attributed to BO stretching vibration of the tetrahedral units. The Raman band at 947 cm-1 is attributed to the antisymmetric stretching modes of tetrahedral boron. The sharp Raman peak at 1037 cm-1 is from the 11-B component such a mode, then it should have a smaller 10-B satellite near (1.03) × (1037) = 1048 cm-1, and indeed a small peak at 1048 is observed. The broad Raman bands at 3186, 3329, 3431, 3509, 3547 and 3576 cm-1 are assigned to water stretching vibrations. Broad infrared bands at 3170, 3322, 3419, 3450, 3493, 3542, 3577 and 3597 cm-1 are also assigned to water stretching vibrations. Infrared bands at 1330, 1352, 1389, 1407, 1421 and 1457 cm-1 are assigned to the antisymmetric stretching vibrations of trigonal boron. The observation of so many bands suggests that there is considerable variation in the structure of ezcurrite. Infrared bands at 1634, 1646 and 1681 cm-1 are assigned to water bending modes. The number of water bending modes is in harmony with the number of water stretching vibrations.

  14. Oncogenic kinase NPM/ALK induces through STAT3 expression of immunosuppressive protein CD274 (PD-L1, B7-H1)

    PubMed Central

    Marzec, Michal; Zhang, Qian; Goradia, Ami; Raghunath, Puthiyaveettil N.; Liu, Xiaobin; Paessler, Michele; Wang, Hong Yi; Wysocka, Maria; Cheng, Mangeng; Ruggeri, Bruce A.; Wasik, Mariusz A.

    2008-01-01

    The mechanisms of malignant cell transformation caused by the oncogenic, chimeric nucleophosmin (NPM)/anaplastic lymphoma kinase (ALK) remain only partially understood, with most of the previous studies focusing mainly on the impact of NPM/ALK on cell survival and proliferation. Here we report that the NPM/ALK-carrying T cell lymphoma (ALK+TCL) cells strongly express the immunosuppressive cell-surface protein CD274 (PD-L1, B7-H1), as determined on the mRNA and protein level. The CD274 expression is strictly dependent on the expression and enzymatic activity of NPM/ALK, as demonstrated by inhibition of the NPM/ALK function in ALK+TCL cells by the small molecule ALK inhibitor CEP-14083 and by documenting CD274 expression in IL-3-depleted BaF3 cells transfected with the wild-type NPM/ALK, but not the kinase-inactive NPM/ALK K210R mutant or empty vector alone. NPM/ALK induces CD274 expression by activating its key signal transmitter, transcription factor STAT3. STAT3 binds to the CD274 gene promoter in vitro and in vivo, as shown in the gel electromobility shift and chromatin immunoprecipitation assays, and is required for the PD-L1 gene expression, as demonstrated by siRNA-mediated STAT3 depletion. These findings identify an additional cell-transforming property of NPM/ALK and describe a direct link between an oncoprotein and an immunosuppressive cell-surface protein. These results also provide an additional rationale to therapeutically target NPM/ALK and STAT3 in ALK+TCL. Finally, they suggest that future immunotherapeutic protocols for this type of lymphoma may need to include the inhibition of NPM/ALK and STAT3 to achieve optimal clinical efficacy. PMID:19088198

  15. The mixed anion mineral parnauite Cu 9[(OH) 10|SO 4|(AsO 4) 2]·7H 2O—A Raman spectroscopic study

    NASA Astrophysics Data System (ADS)

    Frost, Ray L.; Keeffe, Eloise C.

    2011-10-01

    The mixed anion mineral parnauite Cu 9[(OH) 10|SO 4|(AsO 4) 2]·7H 2O from two localities namely Cap Garonne Mine, Le Pradet, France and Majuba Hill mine, Pershing County, Nevada, USA has been studied by Raman spectroscopy. The Raman spectrum of the French sample is dominated by an intense band at 975 cm -1 assigned to the ν1 (SO 4) 2- symmetric stretching mode and Raman bands at 1077 and 1097 cm -1 may be attributed to the ν3 (SO 4) 2- antisymmetric stretching mode. Two Raman bands 1107 and 1126 cm -1 are assigned to carbonate CO 32- symmetric stretching bands and confirms the presence of carbonate in the structure of parnauite. The comparatively sharp band for the Pershing County mineral at 976 cm -1 is assigned to the ν1 (SO 4) 2- symmetric stretching mode and a broad spectral profile centered upon 1097 cm -1 is attributed to the ν3 (SO 4) 2- antisymmetric stretching mode. Two intense bands for the Pershing County mineral at 851 and 810 cm -1 are assigned to the ν1 (AsO 4) 3- symmetric stretching and ν3 (AsO 4) 3- antisymmetric stretching modes. Two Raman bands for the French mineral observed at 725 and 777 cm -1 are attributed to the ν3 (AsO 4) 3- antisymmetric stretching mode. For the French mineral, a low intensity Raman band is observed at 869 cm -1 and is assigned to the ν1 (AsO 4) 3- symmetric stretching vibration. Chemical composition of parnauite remains open and the question may be raised is parnauite a solid solution of two or more minerals such as a copper hydroxy-arsenate and a copper hydroxy sulphate.

  16. Experimental study of sono-crystallisation of ZnSO4·7H2O, and interpretation by the segregation theory.

    PubMed

    Harzali, H; Baillon, F; Louisnard, O; Espitalier, F; Mgaidi, A

    2011-09-01

    Power ultrasound is known to enhance crystals nucleation, and nucleation times can be reduced by one up to three orders of magnitude for several organic or inorganic crystals. The precise physics involved in this phenomenon still remains unclear, and various mechanisms involving the action of inertial cavitation bubbles have been proposed. In this paper, two of these mechanisms, pressure and segregation effects, are examined. The first one concerns the variations of supersaturation induced by the high pressures appearing in the neighbourhood of a collapsing bubble, and the second one results from the modification of clusters distribution in the vicinity of bubble. Crystallisation experiments were performed on zinc sulphate heptahydrate ZnSO(4)·7H(2)O, which has been chosen for its pressure-independent solubility, so that pressure variations have no effect on supersaturation. As observed in past studies on other species, induction times were found lower under insonification than under silent conditions at low supersaturations, which casts some doubts on a pure pressure effect. The interfacial energy between the solid and the solution was estimated from induction times obtained in silent conditions, and, using classical nucleation theory, the steady-state distribution of the clusters was calculated. Segregation theory was then applied to calculate the over-concentrations of n-sized clusters at the end of the collapse of a 4 μm bubble driven at 20 kHz by different acoustic pressures. The over-concentration of clusters close to the critical size near a collapsing bubble was found to reach more than one order of magnitude, which may favour the direct attachment process between such clusters, and enhance the global nucleation kinetics. Copyright © 2011 Elsevier B.V. All rights reserved.

  17. Coefficient Omega Bootstrap Confidence Intervals: Nonnormal Distributions

    ERIC Educational Resources Information Center

    Padilla, Miguel A.; Divers, Jasmin

    2013-01-01

    The performance of the normal theory bootstrap (NTB), the percentile bootstrap (PB), and the bias-corrected and accelerated (BCa) bootstrap confidence intervals (CIs) for coefficient omega was assessed through a Monte Carlo simulation under conditions not previously investigated. Of particular interests were nonnormal Likert-type and binary items.…

  18. Precise Interval Timer for Software Defined Radio

    NASA Technical Reports Server (NTRS)

    Pozhidaev, Aleksey (Inventor)

    2014-01-01

    A precise digital fractional interval timer for software defined radios which vary their waveform on a packet-by-packet basis. The timer allows for variable length in the preamble of the RF packet and allows to adjust boundaries of the TDMA (Time Division Multiple Access) Slots of the receiver of an SDR based on the reception of the RF packet of interest.

  19. Coefficient Alpha Bootstrap Confidence Interval under Nonnormality

    ERIC Educational Resources Information Center

    Padilla, Miguel A.; Divers, Jasmin; Newton, Matthew

    2012-01-01

    Three different bootstrap methods for estimating confidence intervals (CIs) for coefficient alpha were investigated. In addition, the bootstrap methods were compared with the most promising coefficient alpha CI estimation methods reported in the literature. The CI methods were assessed through a Monte Carlo simulation utilizing conditions…

  20. Happiness Scale Interval Study. Methodological Considerations

    ERIC Educational Resources Information Center

    Kalmijn, W. M.; Arends, L. R.; Veenhoven, R.

    2011-01-01

    The Happiness Scale Interval Study deals with survey questions on happiness, using verbal response options, such as "very happy" and "pretty happy". The aim is to estimate what degrees of happiness are denoted by such terms in different questions and languages. These degrees are expressed in numerical values on a continuous…

  1. Coefficient Alpha Bootstrap Confidence Interval under Nonnormality

    ERIC Educational Resources Information Center

    Padilla, Miguel A.; Divers, Jasmin; Newton, Matthew

    2012-01-01

    Three different bootstrap methods for estimating confidence intervals (CIs) for coefficient alpha were investigated. In addition, the bootstrap methods were compared with the most promising coefficient alpha CI estimation methods reported in the literature. The CI methods were assessed through a Monte Carlo simulation utilizing conditions…

  2. Coefficient Omega Bootstrap Confidence Intervals: Nonnormal Distributions

    ERIC Educational Resources Information Center

    Padilla, Miguel A.; Divers, Jasmin

    2013-01-01

    The performance of the normal theory bootstrap (NTB), the percentile bootstrap (PB), and the bias-corrected and accelerated (BCa) bootstrap confidence intervals (CIs) for coefficient omega was assessed through a Monte Carlo simulation under conditions not previously investigated. Of particular interests were nonnormal Likert-type and binary items.…

  3. MEETING DATA QUALITY OBJECTIVES WITH INTERVAL INFORMATION

    EPA Science Inventory

    Immunoassay test kits are promising technologies for measuring analytes under field conditions. Frequently, these field-test kits report the analyte concentrations as falling in an interval between minimum and maximum values. Many project managers use field-test kits only for scr...

  4. Confidence Trick: The Interpretation of Confidence Intervals

    ERIC Educational Resources Information Center

    Foster, Colin

    2014-01-01

    The frequent misinterpretation of the nature of confidence intervals by students has been well documented. This article examines the problem as an aspect of the learning of mathematical definitions and considers the tension between parroting mathematically rigorous, but essentially uninternalized, statements on the one hand and expressing…

  5. Interval coding. II. Dendrite-dependent mechanisms.

    PubMed

    Doiron, Brent; Oswald, Anne-Marie M; Maler, Leonard

    2007-04-01

    The rich temporal structure of neural spike trains provides multiple dimensions to code dynamic stimuli. Popular examples are spike trains from sensory cells where bursts and isolated spikes can serve distinct coding roles. In contrast to analyses of neural coding, the cellular mechanics of burst mechanisms are typically elucidated from the neural response to static input. Bridging the mechanics of bursting with coding of dynamic stimuli is an important step in establishing theories of neural coding. Electrosensory lateral line lobe (ELL) pyramidal neurons respond to static inputs with a complex dendrite-dependent burst mechanism. Here we show that in response to dynamic broadband stimuli, these bursts lack some of the electrophysiological characteristics observed in response to static inputs. A simple leaky integrate-and-fire (LIF)-style model with a dendrite-dependent depolarizing afterpotential (DAP) is sufficient to match both the output statistics and coding performance of experimental spike trains. We use this model to investigate a simplification of interval coding where the burst interspike interval (ISI) codes for the scale of a canonical upstroke rather than a multidimensional stimulus feature. Using this stimulus reduction, we compute a quantization of the burst ISIs and the upstroke scale to show that the mutual information rate of the interval code is maximized at a moderate DAP amplitude. The combination of a reduced description of ELL pyramidal cell bursting and a simplification of the interval code increases the generality of ELL burst codes to other sensory modalities.

  6. Equidistant Intervals in Perspective Photographs and Paintings

    PubMed Central

    2016-01-01

    Human vision is extremely sensitive to equidistance of spatial intervals in the frontal plane. Thresholds for spatial equidistance have been extensively measured in bisecting tasks. Despite the vast number of studies, the informational basis for equidistance perception is unknown. There are three possible sources of information for spatial equidistance in pictures, namely, distances in the picture plane, in physical space, and visual space. For each source, equidistant intervals were computed for perspective photographs of walls and canals. Intervals appear equidistant if equidistance is defined in visual space. Equidistance was further investigated in paintings of perspective scenes. In appraisals of the perspective skill of painters, emphasis has been on accurate use of vanishing points. The current study investigated the skill of painters to depict equidistant intervals. Depicted rows of equidistant columns, tiles, tapestries, or trees were analyzed in 30 paintings and engravings. Computational analysis shows that from the middle ages until now, artists either represented equidistance in physical space or in a visual space of very limited depth. Among the painters and engravers who depict equidistance in a highly nonveridical visual space are renowned experts of linear perspective. PMID:27698983

  7. 47 CFR 52.35 - Porting Intervals.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Portability § 52.35 Porting Intervals. (a) All telecommunications carriers required by the Commission to port telephone numbers must complete a simple wireline-to-wireline or simple intermodal port request within one... p.m. local time for a simple port request to be eligible for activation at midnight on the same...

  8. 47 CFR 52.35 - Porting Intervals.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Portability § 52.35 Porting Intervals. (a) All telecommunications carriers required by the Commission to port telephone numbers must complete a simple wireline-to-wireline or simple intermodal port request within one... p.m. local time for a simple port request to be eligible for activation at midnight on the same...

  9. 47 CFR 52.35 - Porting Intervals.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Portability § 52.35 Porting Intervals. (a) All telecommunications carriers required by the Commission to port telephone numbers must complete a simple wireline-to-wireline or simple intermodal port request within one... p.m. local time for a simple port request to be eligible for activation at midnight on the same...

  10. 47 CFR 52.35 - Porting Intervals.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Portability § 52.35 Porting Intervals. (a) All telecommunications carriers required by the Commission to port telephone numbers must complete a simple wireline-to-wireline or simple intermodal port request within one... p.m. local time for a simple port request to be eligible for activation at midnight on the same...

  11. MEETING DATA QUALITY OBJECTIVES WITH INTERVAL INFORMATION

    EPA Science Inventory

    Immunoassay test kits are promising technologies for measuring analytes under field conditions. Frequently, these field-test kits report the analyte concentrations as falling in an interval between minimum and maximum values. Many project managers use field-test kits only for scr...

  12. Physiological adjustments to intensive interval treadmill training

    PubMed Central

    Pyke, F. S.; Elliott, B. C.; Morton, A. R.; Roberts, A. D.

    1974-01-01

    During a one month training period, eight active men, aged 23-35 years, completed sixteen 30 minute sessions of high intensity interval (5 second work bouts at 16.9 km/hr up 20-25% grade alternated with 10 second rest intervals) treadmill work. In this training period, V̇O2, V̇E and blood lactate in a 10 minute run at 12.9 km/hr on a level treadmill were unchanged but heart rate during this work decreased by an average of 9 beats/min. During a 4 minute interval work effort at the training intensity, blood lactate accumulation decreased by 40.4%. In exhausting work, mean values of V̇O2, V̇E and blood lactate increased by 6.2%, 8.2% and 31.6% respectively. Maximal heart rate decreased by an average of 4 beats/min. The average work production of the men in the training sessions improved by 64.5% from 28,160 kgm to 43,685 kgm. No significant improvements were observed in either a short sprint or a stair climbing test which assessed the ability to generate mechanical power from alactacid anaerobic sources. It was concluded that the training regime is an effective method of producing a high total work output in competitive athletes and results in improvements in aerobic power, glycolytic capacity and ability to tolerate the short duration interval work encountered in many games.

  13. Learned Interval Time Facilitates Associate Memory Retrieval

    ERIC Educational Resources Information Center

    van de Ven, Vincent; Kochs, Sarah; Smulders, Fren; De Weerd, Peter

    2017-01-01

    The extent to which time is represented in memory remains underinvestigated. We designed a time paired associate task (TPAT) in which participants implicitly learned cue-time-target associations between cue-target pairs and specific cue-target intervals. During subsequent memory testing, participants showed increased accuracy of identifying…

  14. Interval scanning photomicrography of microbial cell populations.

    NASA Technical Reports Server (NTRS)

    Casida, L. E., Jr.

    1972-01-01

    A single reproducible area of the preparation in a fixed focal plane is photographically scanned at intervals during incubation. The procedure can be used for evaluating the aerobic or anaerobic growth of many microbial cells simultaneously within a population. In addition, the microscope is not restricted to the viewing of any one microculture preparation, since the slide cultures are incubated separately from the microscope.

  15. Toward Using Confidence Intervals to Compare Correlations

    ERIC Educational Resources Information Center

    Zou, Guang Yong

    2007-01-01

    Confidence intervals are widely accepted as a preferred way to present study results. They encompass significance tests and provide an estimate of the magnitude of the effect. However, comparisons of correlations still rely heavily on significance testing. The persistence of this practice is caused primarily by the lack of simple yet accurate…

  16. An Empirical Method for Establishing Positional Confidence Intervals Tailored for Composite Interval Mapping of QTL

    USDA-ARS?s Scientific Manuscript database

    Improved genetic resolution and availability of sequenced genomes have made positional cloning of moderate-effect QTL (quantitative trait loci) realistic in several systems, emphasizing the need for precise and accurate derivation of positional confidence intervals (CIs). Support interval (SI) meth...

  17. Haematological Reference Intervals in a Multiethnic Population

    PubMed Central

    Ambayya, Angeli; Su, Anselm Ting; Osman, Nadila Haryani; Nik-Samsudin, Nik Rosnita; Khalid, Khadijah; Chang, Kian Meng; Sathar, Jameela; Rajasuriar, Jay Suriar; Yegappan, Subramanian

    2014-01-01

    Introduction Similar to other populations, full blood count reference (FBC) intervals in Malaysia are generally derived from non-Malaysian subjects. However, numerous studies have shown significant differences between and within populations supporting the need for population specific intervals. Methods Two thousand seven hundred twenty five apparently healthy adults comprising all ages, both genders and three principal races were recruited through voluntary participation. FBC was performed on two analysers, Sysmex XE-5000 and Unicel DxH 800, in addition to blood smears and haemoglobin analysis. Serum ferritin, soluble transferrin receptor and C-reactive protein assays were performed in selected subjects. All parameters of qualified subjects were tested for normality followed by determination of reference intervals, measures of central tendency and dispersion along with point estimates for each subgroup. Results Complete data was available in 2440 subjects of whom 56% (907 women and 469 men) were included in reference interval calculation. Compared to other populations there were significant differences for haemoglobin, red blood cell count, platelet count and haematocrit in Malaysians. There were differences between men and women, and between younger and older men; unlike in other populations, haemoglobin was similar in younger and older women. However ethnicity and smoking had little impact. 70% of anemia in premenopausal women, 24% in postmenopausal women and 20% of males is attributable to iron deficiency. There was excellent correlation between Sysmex XE-5000 and Unicel DxH 800. Conclusion Our data confirms the importance of population specific haematological parameters and supports the need for local guidelines rather than adoption of generalised reference intervals and cut-offs. PMID:24642526

  18. Exact and Asymptotic Weighted Logrank Tests for Interval Censored Data: The interval R package

    PubMed Central

    Fay, Michael P.; Shaw, Pamela A.

    2014-01-01

    For right-censored data perhaps the most commonly used tests are weighted logrank tests, such as the logrank and Wilcoxon-type tests. In this paper we review several generalizations of those weighted logrank tests to interval-censored data and present an R package, interval, to implement many of them. The interval package depends on the perm package, also presented here, which performs exact and asymptotic linear permutation tests. The perm package performs many of the tests included in the already available coin package, and provides an independent validation of coin. We review analysis methods for interval-censored data, and we describe and show how to use the interval and perm packages. PMID:25285054

  19. Electrocardiographic intervals associated with incident atrial fibrillation: Dissecting the QT interval.

    PubMed

    Roberts, Jason D; Soliman, Elsayed Z; Alonso, Alvaro; Vittinghoff, Eric; Chen, Lin Y; Loehr, Laura; Marcus, Gregory M

    2017-05-01

    Prolongation of the QT interval has been associated with an increased risk of developing atrial fibrillation (AF), but the responsible mechanism remains unknown. The aims of this study were to subdivide the QT interval into its components and identify the resultant electrocardiographic interval(s) responsible for the association with AF. Predefined QT-interval components were assessed for association with incident AF in the Atherosclerosis Risk in Communities study using Cox proportional hazards models. Hazard ratios (HRs) were calculated per 1-SD increase in each component. Among QT-interval components exhibiting significant associations, additional analyses evaluating long extremes, defined as greater than the 95(th) percentile, were performed. Of the 14,625 individuals, 1505 (10.3%) were diagnosed with incident AF during a mean follow-up period of 17.6 years. After multivariable adjustment, QT-interval components involved in repolarization, but not depolarization, exhibited significant associations with incident AF, including a longer ST segment (HR 1.27; 95% confidence interval [CI] 1.14-1.41; P < .001) and a prolonged T-wave onset to T-wave peak (T-onset to T-peak) (HR 1.13; 95% CI 1.07-1.20; P < .001). Marked prolongation of the ST segment (HR 1.31; 95% CI 1.04-1.64; P = .022) and T-onset to T-peak (HR 1.36; 95% CI 1.09-1.69; P = .006) was also associated with an increased risk of incident AF. The association between a prolonged QT interval and incident AF is primarily explained by components involved in ventricular repolarization: prolongation of the ST segment and T-onset to T-peak. These observations suggest that prolongation of phases 2 and 3 of the cardiac action potential drives the association between the QT interval and AF risk. Copyright © 2017 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  20. A novel technique for measurement of thermal rate constants and temperature dependences of dissociative recombination: CO2+, CF3+, N2O+, C7H8+, C7H7+, C6H6+, C6H5+, C5H6+, C4H4+, and C3H3+

    NASA Astrophysics Data System (ADS)

    Fournier, Joseph A.; Shuman, Nicholas S.; Melko, Joshua J.; Ard, Shaun G.; Viggiano, Albert A.

    2013-04-01

    A novel technique using a flowing afterglow-Langmuir probe apparatus for measurement of temperature dependences of rate constants for dissociative recombination (DR) is presented. Low (˜1011 cm-3) concentrations of a neutral precursor are added to a noble gas/electron afterglow plasma thermalized at 300-500 K. Charge exchange yields one or many cation species, each of which may undergo DR. Relative ion concentrations are monitored at a fixed reaction time while the initial plasma density is varied between 109 and 1010 cm-3. Modeling of the decrease in concentration of each cation relative to the non-recombining noble gas cation yields the rate constant for DR. The technique is applied to several species (O2+, CO2+, CF3+, N2O+) with previously determined 300 K values, showing excellent agreement. The measurements of those species are extended to 500 K, with good agreement to literature values where they exist. Measurements are also made for a range of CnHm+ (C7H7+, C7H8+, C5H6+, C4H4+, C6H5+, C3H3+, and C6H6+) derived from benzene and toluene neutral precursors. CnHm+ DR rate constants vary from 8-12 × 10-7 cm3 s-1 at 300 K with temperature dependences of approximately T-0.7. Where prior measurements exist these results are in agreement, with the exception of C3H3+ where the present results disagree with a previously reported flat temperature dependence.

  1. A novel technique for measurement of thermal rate constants and temperature dependences of dissociative recombination: CO2(+), CF3(+), N2O(+), C7H8(+), C7H7(+), C6H6(+), C6H5(+), C5H6(+), C4H4(+), and C3H3(+).

    PubMed

    Fournier, Joseph A; Shuman, Nicholas S; Melko, Joshua J; Ard, Shaun G; Viggiano, Albert A

    2013-04-21

    A novel technique using a flowing afterglow-Langmuir probe apparatus for measurement of temperature dependences of rate constants for dissociative recombination (DR) is presented. Low (~10(11) cm(-3)) concentrations of a neutral precursor are added to a noble gas∕electron afterglow plasma thermalized at 300-500 K. Charge exchange yields one or many cation species, each of which may undergo DR. Relative ion concentrations are monitored at a fixed reaction time while the initial plasma density is varied between 10(9) and 10(10) cm(-3). Modeling of the decrease in concentration of each cation relative to the non-recombining noble gas cation yields the rate constant for DR. The technique is applied to several species (O2(+), CO2(+), CF3(+), N2O(+)) with previously determined 300 K values, showing excellent agreement. The measurements of those species are extended to 500 K, with good agreement to literature values where they exist. Measurements are also made for a range of CnHm(+) (C7H7(+), C7H8(+), C5H6(+), C4H4(+), C6H5(+), C3H3(+), and C6H6(+)) derived from benzene and toluene neutral precursors. CnHm(+) DR rate constants vary from 8-12 × 10(-7) cm(3) s(-1) at 300 K with temperature dependences of approximately T(-0.7). Where prior measurements exist these results are in agreement, with the exception of C3H3(+) where the present results disagree with a previously reported flat temperature dependence.

  2. Cationic cobalt(III) complex as anion receptor for biologically important anion: Synthesis, characterization and X-ray structure of [Co(phen) 3](C 7H 4NSO 3) 3.8.5H 2O where C 7H 4NSO 3 = saccharinate ion

    NASA Astrophysics Data System (ADS)

    Singh, Ajnesh; Sharma, Raj Pal; Brandão, Paula; Felix, Vitor; Venugopalan, Paloth

    2008-11-01

    In an effort to explore [Co(phen) 3] 3+ complex cation as anion receptor for biologically important saccharinate ion, yellow coloured single crystals of [Co(phen) 3](C 7H 4NSO 3) 3.8.5H 2O were obtained by slow evaporation of solution, obtained by mixing the separately dissolved, tris(1,10-phenanthroline)cobalt(III)chloride and sodium saccharinate in aqueous medium in 1:3 molar ratio. The newly synthesized complex salt was characterized by elemental analysis, TGA, conductance, solubility product measurements and spectroscopic studies (IR, UV/Visible, 1H and 13C NMR). Single crystal X-ray structure determination of [Co(phen) 3](C 7H 4NSO 3) 3.8.5H 2O revealed that compound crystallizes in the triclinic crystal system with space group P1¯ where a = 12.3795(4), b = 12.7598(4), c = 19.0414(5) Å, α = 71.544(2), β = 76.457(2), γ = 9 77.213(2)°, V = 2738.19(14) Å 3, Z = 2. The crystal lattice is stabilized by hydrogen bonding interactions of type O sbnd H⋯O and C sbnd H⋯O (through second sphere coordination) besides the electrostatic forces of attraction. The solubility product and conductance measurements indicated that the affinity of cationic tris(1,10-phenanthroline) cobalt (III), [Co(phen) 3] 3+ is greater for saccharinate ion than for chloride ion in aqueous medium. The structural studies suggest that [Co(phen) 3] 3+ is a potential anion receptor for the saccharinate ion.

  3. The role of human cytochrome P4503A4 in biotransformation of tissue-specific derivatives of 7H-dibenzo[c,g]carbazole

    SciTech Connect

    Mesarosova, Monika; Valovicova, Zuzana; Srancikova, Annamaria; Krajcovicova, Zdenka; Milcova, Alena; Sokolova, Romana; Schmuczerova, Jana; Topinka, Jan; Gabelova, Alena

    2011-09-15

    The environmental pollutant 7H-dibenzo[c,g]carbazole (DBC) and its derivative, 5,9-dimethylDBC (DiMeDBC), produced significant and dose-dependent levels of micronuclei followed by a substantial increase in the frequency of apoptotic cells in the V79MZh3A4 cell line stably expressing the human cytochrome P450 (hCYP) 3A4. In contrast, neither micronuclei nor apoptosis were found in cells exposed to the sarcomagenic carcinogen, N-methylDBC (N-MeDBC). A slight but significant level of gene mutations and DNA adducts detected in V79MZh3A4 cells treated with N-MeDBC, only at the highest concentration (30 {mu}M), revealed that this sarcomagenic carcinogen was also metabolized by hCYP3A4. Surprisingly, DBC increased the frequency of 6-thioguanine resistant (6-TG{sup r}) mutations only at the highest concentration (30 {mu}M), while DiMeDBC failed to increase the frequency of these mutations. The resistance to 6-thioguanine is caused by the mutations in the hypoxanthine-guanine phosphoribosyltransferase (Hprt) gene. The molecular analysis of the coding region of Hprt gene showed a deletion of the entire exon 8 in DiMeDBC-induced 6-TG{sup r} mutants, while no changes in the nucleotide sequences were identified in 6-TG{sup r} mutants produced by DBC and N-MeDBC. Based on our results, we suggest that hCYP3A4 is involved in the metabolism of DBC and its tissue-specific derivatives. While hCYP3A4 probably plays an important role in biotransformation of the liver carcinogens, DBC and DiMeDBC, it might only have a marginal function in N-MeDBC metabolism. - Highlights: > DBC activation via CYP3A4 resulted in micronuclei, DNA adduct formation and mutations in V79MZh3A4 cells. > The CYP3A4-mediated DiMeDBC activation caused micronuclei followed by apoptosis in V79MZh3A4 cells. > The genotoxic effects produced by N-MeDBC in V79MZh3A4 cells were negligible. > The hCYP3A4 may play an important role in DBC and DiMeDBC metabolism. > The CYP3A4 might only have a marginal function in N

  4. A Robust Confidence Interval for Samples of Five Observations.

    DTIC Science & Technology

    1979-11-01

    A robust confidence interval using biweights for the case of five observations is proposed when the underlying distribution has somewhat heavier...probabilities, the intervals proposed are highly efficient, in terms of the expected length of the confidence interval . (Author)

  5. Reliable prediction intervals with regression neural networks.

    PubMed

    Papadopoulos, Harris; Haralambous, Haris

    2011-10-01

    This paper proposes an extension to conventional regression neural networks (NNs) for replacing the point predictions they produce with prediction intervals that satisfy a required level of confidence. Our approach follows a novel machine learning framework, called Conformal Prediction (CP), for assigning reliable confidence measures to predictions without assuming anything more than that the data are independent and identically distributed (i.i.d.). We evaluate the proposed method on four benchmark datasets and on the problem of predicting Total Electron Content (TEC), which is an important parameter in trans-ionospheric links; for the latter we use a dataset of more than 60000 TEC measurements collected over a period of 11 years. Our experimental results show that the prediction intervals produced by our method are both well calibrated and tight enough to be useful in practice. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Efficient computation of parameter confidence intervals

    NASA Technical Reports Server (NTRS)

    Murphy, Patrick C.

    1987-01-01

    An important step in system identification of aircraft is the estimation of stability and control derivatives from flight data along with an assessment of parameter accuracy. When the maximum likelihood estimation technique is used, parameter accuracy is commonly assessed by the Cramer-Rao lower bound. It is known, however, that in some cases the lower bound can be substantially different from the parameter variance. Under these circumstances the Cramer-Rao bounds may be misleading as an accuracy measure. This paper discusses the confidence interval estimation problem based on likelihood ratios, which offers a more general estimate of the error bounds. Four approaches are considered for computing confidence intervals of maximum likelihood parameter estimates. Each approach is applied to real flight data and compared.

  7. Constraint-based Attribute and Interval Planning

    NASA Technical Reports Server (NTRS)

    Jonsson, Ari; Frank, Jeremy

    2013-01-01

    In this paper we describe Constraint-based Attribute and Interval Planning (CAIP), a paradigm for representing and reasoning about plans. The paradigm enables the description of planning domains with time, resources, concurrent activities, mutual exclusions among sets of activities, disjunctive preconditions and conditional effects. We provide a theoretical foundation for the paradigm, based on temporal intervals and attributes. We then show how the plans are naturally expressed by networks of constraints, and show that the process of planning maps directly to dynamic constraint reasoning. In addition, we de ne compatibilities, a compact mechanism for describing planning domains. We describe how this framework can incorporate the use of constraint reasoning technology to improve planning. Finally, we describe EUROPA, an implementation of the CAIP framework.

  8. Efficient computation of parameter confidence intervals

    NASA Technical Reports Server (NTRS)

    Murphy, Patrick C.

    1987-01-01

    An important step in system identification of aircraft is the estimation of stability and control derivatives from flight data along with an assessment of parameter accuracy. When the maximum likelihood estimation technique is used, parameter accuracy is commonly assessed by the Cramer-Rao lower bound. It is known, however, that in some cases the lower bound can be substantially different from the parameter variance. Under these circumstances the Cramer-Rao bounds may be misleading as an accuracy measure. This paper discusses the confidence interval estimation problem based on likelihood ratios, which offers a more general estimate of the error bounds. Four approaches are considered for computing confidence intervals of maximum likelihood parameter estimates. Each approach is applied to real flight data and compared.

  9. Constraint-based Attribute and Interval Planning

    NASA Technical Reports Server (NTRS)

    Jonsson, Ari; Frank, Jeremy

    2013-01-01

    In this paper we describe Constraint-based Attribute and Interval Planning (CAIP), a paradigm for representing and reasoning about plans. The paradigm enables the description of planning domains with time, resources, concurrent activities, mutual exclusions among sets of activities, disjunctive preconditions and conditional effects. We provide a theoretical foundation for the paradigm, based on temporal intervals and attributes. We then show how the plans are naturally expressed by networks of constraints, and show that the process of planning maps directly to dynamic constraint reasoning. In addition, we de ne compatibilities, a compact mechanism for describing planning domains. We describe how this framework can incorporate the use of constraint reasoning technology to improve planning. Finally, we describe EUROPA, an implementation of the CAIP framework.

  10. Partitioned-Interval Quantum Optical Communications Receiver

    NASA Technical Reports Server (NTRS)

    Vilnrotter, Victor A.

    2013-01-01

    The proposed quantum receiver in this innovation partitions each binary signal interval into two unequal segments: a short "pre-measurement" segment in the beginning of the symbol interval used to make an initial guess with better probability than 50/50 guessing, and a much longer segment used to make the high-sensitivity signal detection via field-cancellation and photon-counting detection. It was found that by assigning as little as 10% of the total signal energy to the pre-measurement segment, the initial 50/50 guess can be improved to about 70/30, using the best available measurements such as classical coherent or "optimized Kennedy" detection.

  11. Using interval logic for order assembly

    SciTech Connect

    Cui, Z.

    1994-12-31

    Temporal logic, in particular, interval logic has been used to represent genome maps and to assist genome map constructions. However, interval logic itself appears to be limited in its expressive power because genome mapping requires various information such as partial order, distance and local orientation. In this paper, we first propose an integrated formalism based on a spatial-temporal logic where the concepts of metric information, local orientation and uncertainty are merged. Then, we present and discuss a deductive and object-oriented data model based on this formalism for a genetic deductive database, and the inference rules required. The formalism supports the maintenance of coarser knowledge of unordered, partially ordered and completely ordered genetic data in a relational hierarchy. We believe that this integrated formalism also provides a formal basis for designing a declarative query language.

  12. The Rotator Interval of the Shoulder

    PubMed Central

    Frank, Rachel M.; Taylor, Dean; Verma, Nikhil N.; Romeo, Anthony A.; Mologne, Timothy S.; Provencher, Matthew T.

    2015-01-01

    Biomechanical studies have shown that repair or plication of rotator interval (RI) ligamentous and capsular structures decreases glenohumeral joint laxity in various directions. Clinical outcomes studies have reported successful outcomes after repair or plication of these structures in patients undergoing shoulder stabilization procedures. Recent studies describing arthroscopic techniques to address these structures have intensified the debate over the potential benefit of these procedures as well as highlighted the differences between open and arthroscopic RI procedures. The purposes of this study were to review the structures of the RI and their contribution to shoulder instability, to discuss the biomechanical and clinical effects of repair or plication of rotator interval structures, and to describe the various surgical techniques used for these procedures and outcomes. PMID:26779554

  13. The effect of high intensity interval exercise on postprandial triacylglycerol and leukocyte activation--monitored for 48 h post exercise.

    PubMed

    Gabriel, Brendan Morris; Pugh, Jamie; Pruneta-Deloche, Valerie; Moulin, Philippe; Ratkevicius, Aivaras; Gray, Stuart Robert

    2013-01-01

    Postprandial phenomenon are thought to contribute to atherogenesis alongside activation of the immune system. A single bout of high intensity interval exercise attenuates postprandial triacylglycerol (TG), although the longevity and mechanisms underlying this observation are unknown. The aims of this study were to determine whether this attenuation in postprandial TG remained 2 days after high intensity interval exercise, to monitor markers of leukocyte activation and investigate the underlying mechanisms. Eight young men each completed two three day trials. On day 1: subjects rested (Control) or performed 5 x 30 s maximal sprints (high intensity interval exercise). On day 2 and 3 subjects consumed high fat meals for breakfast and 3 h later for lunch. Blood samples were taken at various times and analysed for TG, glucose and TG-rich lipoprotein (TRL)-bound LPL-dependent TRL-TG hydrolysis (LTTH). Flow cytometry was used to evaluate granulocyte, monocyte and lymphocyte CD11b and CD36 expression. On day 2 after high intensity interval exercise TG area under the curve was lower (P<0.05) (7.46 ± 1.53 mmol/l/7h) compared to the control trial (9.47 ± 3 .04 mmol/l/7h) with no differences during day 3 of the trial. LTTH activity was higher (P<0.05) after high intensity interval exercise, at 2 hours of day 2, compared to control. Granulocyte, monocyte and lymphocyte CD11b expression increased with time over day 2 and 3 of the study (P<0.0001). Lymphocyte and monocyte CD36 expression decreased with time over day 2 and 3 (P<0.05). There were no differences between trials in CD11b and CD36 expression on any leukocytes. A single session of high intensity interval exercise attenuated postprandial TG on day 2 of the study, with this effect abolished by day 3.The reduction in postprandial TG was associated with an increase in LTTH. High intensity interval exercise had no effect on postprandial responses of CD11b or CD36.

  14. Temporal control mechanism in equaled interval tapping.

    PubMed

    Yamada, M

    1996-05-01

    Subjects who were at intermediate levels of musical performance made equaled interval tapping in several tempos. The temporal fluctuation for the tapping was observed and analysed. The power spectrum of the fluctuation showed a critical phenomenon at around a frequency which corresponds to the period of 20 taps, for all tempos and all subjects, i.e., the slope of the spectrum was flat or had a positive value in the high frequency region above the critical frequency but it increased as the frequency decreased in the low frequency region below the critical frequency. Moreover, auto-regressive models and Akaike's information criterion were introduced to determine the critical tap number. The order of the best auto-regressive model for the temporal fluctuation data was distributed around 20 taps. These results show that the memory capacity of 20 taps governs the control of equaled interval tapping. To interpret the critical phenomenon of 20 taps with the memory capacity of the short term memory, the so called magic number seven, a simple chunking assumption was introduced; subjects might have unconsciously chunked every three taps during the tapping. If the chunking assumption is true, when subjects consciously chunk every seven taps, the memory capacity of taps should shift to about 50 taps. To test if the assumption is true or not, subjects made a three-beat rhythm tapping and a seven-beat rhythm tapping with equaled intervals. As a result, the memory capacity for these accented tappings were also estimated as 20 taps. This suggests that the critical phenomenon cannot be explained by the chunking assumption and the magic number seven, rather this finding suggests that there exists a memory capacity of 20 taps and this is used for equaled interval tapping.

  15. New Madrid seismic zone recurrence intervals

    SciTech Connect

    Schweig, E.S. Center for Earthquake Research and Information, Memphis, TN ); Ellis, M.A. )

    1993-03-01

    Frequency-magnitude relations in the New Madrid seismic zone suggest that great earthquakes should occur every 700--1,200 yrs, implying relatively high strain rates. These estimates are supported by some geological and GPS results. Recurrence intervals of this order should have produced about 50 km of strike-slip offset since Miocene time. No subsurface evidence for such large displacements is known within the seismic zone. Moreover, the irregular fault pattern forming a compressive step that one sees today is not compatible with large displacements. There are at least three possible interpretations of the observations of short recurrence intervals and high strain rates, but apparently youthful fault geometry and lack of major post-Miocene deformation. One is that the seismological and geodetic evidence are misleading. A second possibility is that activity in the region is cyclic. That is, the geological and geodetic observations that suggest relatively short recurrence intervals reflect a time of high, but geologically temporary, pore-fluid pressure. Zoback and Zoback have suggested such a model for intraplate seismicity in general. Alternatively, the New Madrid seismic zone is geologically young feature that has been active for only the last few tens of thousands of years. In support of this, observe an irregular fault geometry associated with a unstable compressive step, a series of en echelon and discontinuous lineaments that may define the position of a youthful linking fault, and the general absence of significant post-Eocene faulting or topography.

  16. Fluctuations of healthy and unhealthy heartbeat intervals

    NASA Astrophysics Data System (ADS)

    Lan, Boon Leong; Toda, Mikito

    2013-04-01

    We show that the RR-interval fluctuations, defined as the difference between successive natural-logarithm of the RR interval, for healthy, congestive-heart-failure (CHF) and atrial-fibrillation (AF) subjects are well modeled by non-Gaussian stable distributions. Our results suggest that healthy or unhealthy RR-interval fluctuation can generally be modeled as a sum of a large number of independent physiological effects which are identically distributed with infinite variance. Furthermore, we show for the first time that one indicator —the scale parameter of the stable distribution— is sufficient to robustly distinguish the three groups of subjects. The scale parameters for healthy subjects are smaller than those for AF subjects but larger than those for CHF subjects —this ordering suggests that the scale parameter could be used to objectively quantify the severity of CHF and AF over time and also serve as an early warning signal for a healthy person when it approaches either boundary of the healthy range.

  17. COMPARISON OF BLOOD PROTEIN AND TARGET ORGAN DNA AND PROTEIN BINDING FOLLOWING TOPICAL APPLICATION OF BENZO[A]PYRENE AND 7H-DIBENZO[C,G]CARBAZOLE TO MICE

    EPA Science Inventory

    7H-Dibenzo[c,g]carbazole (DBC) induces skin and liver tumors in mice following topical application, whereas benzo[a]pyrene (BP) induces only skin tumors. DBC also binds to liver DNA to a much greater extent than does BP. The present study examined factors that might account for t...

  18. COMPARISON OF BLOOD PROTEIN AND TARGET ORGAN DNA AND PROTEIN BINDING FOLLOWING TOPICAL APPLICATION OF BENZO[A]PYRENE AND 7H-DIBENZO[C,G]CARBAZOLE TO MICE

    EPA Science Inventory

    7H-Dibenzo[c,g]carbazole (DBC) induces skin and liver tumors in mice following topical application, whereas benzo[a]pyrene (BP) induces only skin tumors. DBC also binds to liver DNA to a much greater extent than does BP. The present study examined factors that might account for t...

  19. Characteristics of supercritical turbulence from Direct Numerical Simulations of C(sub 7)H(sub 16)/N(sub 2) and O(sub 2)/H(sub 2)

    NASA Technical Reports Server (NTRS)

    Okong'o, N. A.; Bellan, J.

    2003-01-01

    Analysis of Direct Numerical Simulations (DNS) transitional states of temporal, supercritical mixing layers for C7H16/N2 and O2/H2 shows that the evolution of all layers is characterized by the formation of high-density-gradient magnitude (HDGM) regions.

  20. One-way ANOVA based on interval information

    NASA Astrophysics Data System (ADS)

    Hesamian, Gholamreza

    2016-08-01

    This paper deals with extending the one-way analysis of variance (ANOVA) to the case where the observed data are represented by closed intervals rather than real numbers. In this approach, first a notion of interval random variable is introduced. Especially, a normal distribution with interval parameters is introduced to investigate hypotheses about the equality of interval means or test the homogeneity of interval variances assumption. Moreover, the least significant difference (LSD method) for investigating multiple comparison of interval means is developed when the null hypothesis about the equality of means is rejected. Then, at a given interval significance level, an index is applied to compare the interval test statistic and the related interval critical value as a criterion to accept or reject the null interval hypothesis of interest. Finally, the method of decision-making leads to some degrees to accept or reject the interval hypotheses. An applied example will be used to show the performance of this method.

  1. MicroRNA-187, down-regulated in clear cell renal cell carcinoma and associated with lower survival, inhibits cell growth and migration though targeting B7-H3

    SciTech Connect

    Zhao, Jun; Lei, Ting; Xu, Congjie; Li, Huan; Ma, Wenmin; Yang, Yunxia; Fan, Shuming; Liu, Yuchen

    2013-08-23

    Highlights: •miR-187 is down-regulated in clear cell renal cell carcinoma (ccRCC). •Down-regulation of miR-187 is associated with poor outcomes in patients with ccRCC. •miR-187 inhibits cell growth and migration though targeting B7-H3 in ccRCC. -- Abstract: Aberrantly expressed microRNAs (miRNAs) are frequently associated with the aggressive malignant behavior of human cancers, including clear cell renal cell carcinoma (ccRCC). Based on the preliminary deep sequencing data, we hypothesized that miR-187 may play an important role in ccRCC development. In this study, we found that miR-187 was down-regulated in both tumor tissue and plasma of ccRCC patients. Lower miR-187 expression levels were associated with higher tumor grade and stage. All patients with high miR-187 expression survived 5 years, while with low miR-187 expression, only 42% survived. Suppressed in vitro proliferation, inhibited in vivo tumor growth, and decreased motility were observed in cells treated with the miR-187 expression vector. Further studies showed that B7 homolog 3 (B7-H3) is a direct target of miR-187. Over-expression of miR-187 decreased B7-H3 mRNA level and repressed B7-H3-3′-UTR reporter activity. Knockdown of B7-H3 using siRNA resulted in similar phenotype changes as that observed for overexpression of miR-187. Our data suggest that miR-187 is emerging as a novel player in the disease state of ccRCC. miR-187 plays a tumor suppressor role in ccRCC.

  2. Hydrido copper clusters supported by dithiocarbamates: oxidative hydride removal and neutron diffraction analysis of [Cu7(H){S2C(aza-15-crown-5)}6].

    PubMed

    Liao, Ping-Kuei; Fang, Ching-Shiang; Edwards, Alison J; Kahlal, Samia; Saillard, Jean-Yves; Liu, C W

    2012-06-18

    Reactions of Cu(I) salts with Na(S(2)CR) (R = N(n)Pr(2), NEt(2), aza-15-crown-5), and (Bu(4)N)(BH(4)) in an 8:6:1 ratio in CH(3)CN solution at room temperature yield the monocationic hydride-centered octanuclear Cu(I) clusters, [Cu(8)(H){S(2)CR}(6)](PF(6)) (R = N(n)Pr(2), 1(H); NEt(2), 2(H); aza-15-crown-5, 3(H)). Further reactions of [Cu(8)(H){S(2)CR}(6)](PF(6)) with 1 equiv of (Bu(4)N)(BH(4)) produced neutral heptanuclear copper clusters, [Cu(7)(H){S(2)CR}(6)] (R = N(n)Pr(2), 4(H); NEt(2), 5(H); aza-15-crown-5, 6(H)) and clusters 4-6 can also be generated from the reaction of Cu(BF(4))(2), Na(S(2)CR), and (Bu(4)N)(BH(4)) in a 7:6:8 molar ratio in CH(3)CN. Reformation of cationic Cu(I)(8) clusters by adding 1 equiv of Cu(I) salt to the neutral Cu(7) clusters in solution is observed. Intriguingly, the central hydride in [Cu(8)(H){S(2)CN(n)Pr(2)}(6)](PF(6)) can be oxidatively removed as H(2) by Ce(NO(3))(6)(2-) to yield [Cu(II)(S(2)CN(n)Pr(2))(2)] exploiting the redox-tolerant nature of dithiocarbamates. Regeneration of hydride-centered octanuclear copper clusters from the [Cu(II)(S(2)CN(n)Pr(2))(2)] can be achieved by reaction with Cu(I) ions and borohydride. The hydride release and regeneration of Cu(I)(8) was monitored by UV-visible titration experiments. To our knowledge, this is the first time that hydride encapsulated within a copper cluster can be released as H(2) via chemical means. All complexes have been fully characterized by (1)H NMR, FT-IR, UV-vis, and elemental analysis, and molecular structures of 1(H), 2(H), and 6(H) were clearly established by single-crystal X-ray diffraction. Both 1(H) and 2(H) exhibit a tetracapped tetrahedral Cu(8) skeleton, which is inscribed within a S(12) icosahedron constituted by six dialkyl dithiocarbamate ligands in a tetrametallic-tetraconnective (μ(2), μ(2)) bonding mode. The copper framework of 6(H) is a tricapped distorted tetrahedron in which the four-coordinate hydride is demonstrated to occupy the central site by

  3. Yegorovite, Na4[Si4O8(OH)4]·7H2O, a new mineral from the Lovozero alkaline pluton, Kola Peninsula

    NASA Astrophysics Data System (ADS)

    Pekov, I. V.; Zubkova, N. V.; Chukanov, N. V.; Zadov, A. E.; Grishin, V. G.; Pushcharovsky, D. Yu.

    2010-12-01

    A new mineral, yegorovite, has been identified in the late hydrothermal, low-temperature assemblage of the Palitra hyperalkaline pegmatite at Mt. Kedykverpakhk, Lovozero alkaline pluton, Kola Peninsula, Russia. The mineral is intimately associated with revdite and megacyclite, earlier natrosilite, microcline, and villiaumite. Yegorovite occurs as coarse, usually split prismatic (up to 0.05 × 0.15 × 1 mm) or lamellar (up to 0.05 × 0.7 × 0.8 mm) crystals. Polysynthetic twins and parallel intergrowths are typical. Mineral individuals are combined in bunches or chaotic groups (up to 2 mm); radial-lamellar clusters are less frequent. Yegorovite is colorless, transparent with vitreous luster. Cleavage is perfect parallel to (010) and (001). Fracture is splintery; crystals are readily split into acicular fragments. The Mohs hardness is ˜2. Density is 1.90(2) g/cm3 (meas) and 1.92 g/cm3 (calc). Yegorovite is biaxial (-), with α = 1.474(2), β = 1.479(2), and γ = 1.482(2), 2 V meas > 70°, 2 V calc = 75°. The optical orientation is X ∧ a ˜ 15°, Y = c, Z = b. The IR spectrum is given. The chemical composition determined using an electron microprobe (H2O determined from total deficiency) is (wt %): 23.28 Na2O, 45.45 SiO2, 31.27 H2Ocalc; the total is 100.00. The empirical formula is Na3.98Si4.01O8.02(OH)3.98 · 7.205H2O. The idealized formula is Na4[Si4O8(OH)4] · 7H2O. Yegorovite is monoclinic, space group P21/ c. The unit-cell dimensions are a = 9.874, b= 12.398, c = 14.897 Å, β = 104.68°, V = 1764.3 Å3, Z = 4. The strongest reflections in the X-ray powder pattern ( d, Å ( I, %)([ hkl]) are 7.21(70)[002], 6.21(72)[012, 020], 4.696(44)[022], 4.003(49)[211], 3.734(46)[ bar 2 13], 3.116(100)[024, 040], 2.463(38)[ bar 4 02, bar 2 43]. The crystal structure was studied by single-crystal method, R hkl = 0.0745. Yegorovite is a representative of a new structural type. Its structure consists of single chains of Si tetrahedrons [Si4O8(OH)4]∞ and sixfold polyhedrons

  4. Feedback functions for variable-interval reinforcement

    PubMed Central

    Nevin, John A.; Baum, William M.

    1980-01-01

    On a given variable-interval schedule, the average obtained rate of reinforcement depends on the average rate of responding. An expression for this feedback effect is derived from the assumptions that free-operant responding occurs in bursts with a constant tempo, alternating with periods of engagement in other activities; that the durations of bursts and other activities are exponentially distributed; and that the rates of initiating and terminating bursts are inversely related. The expression provides a satisfactory account of the data of three experiments. PMID:16812187

  5. [Normal confidence interval for a summary measure].

    PubMed

    Bernard, P M

    2000-10-01

    This paper proposes an approach for calculating the normal confidence interval of a weighted summary measure which requires a particular continuous transformation for its variance estimation. By using the transformation properties and applying the delta method, the variance of transformed measure is easily expressed in terms of the transformed specific measure variances and the squared weights. The confidence limits of the summary measure are easily deduced by inverse transformation of those of transformed measure. The method is illustrated by applying it to some well known epidemiological measures. It seems appropriate for application in stratified analysis context where size allows normal approximation.

  6. Differential pulse interval and width modulated code

    NASA Astrophysics Data System (ADS)

    Sato, M.; Murata, M.; Namekawa, T.

    1980-03-01

    The Differential PIWM Code is described as an application of PIWM Code in voice signal transmission. The differential value between adjacent sampled amplitudes is coded into PIWM Code in such a way as, making the sampling interval shorter for the steeper slope of the signal as well as companding in amplitude, coding and transmitting an absolute value, (say 0 to avoid accumulating the error) and differentiating between the digital signals instead of analogs. The relation among signal frequency, amplitude and S/N was determined.

  7. Asymptotic Theory for Nonparametric Confidence Intervals.

    DTIC Science & Technology

    1982-07-01

    distributions. Ann. Math Statist. 14, 56-62. 24. ROY, S.N. and POTTHOFF, R.F. (1958). Confidence bounds on vector analogues of the "ratio of the mean" and...fl c,~_________ 14L TITLE feed &MV) S. TYPE or REPORT a PeftOo COVx:REC Asympeocic Theory for Nonaparuetric Technical Report Confidence Intevals 6...S..C-0S78 UNCLASSIFIED TŗU *uuuuumuuumhhhhmhhhm_4 ASYMPTOTIC THEORY FOR NONPARAMETRIC CONFIDENCE INTERVALS by Peter W. Glynn TECHNICAL REPORT NO. 63

  8. Easy identification of generalized common and conserved nested intervals.

    PubMed

    de Montgolfier, Fabien; Raffinot, Mathieu; Rusu, Irena

    2014-07-01

    In this article we explain how to easily compute gene clusters, formalized by classical or generalized nested common or conserved intervals, between a set of K genomes represented as K permutations. A b-nested common (resp. conserved) interval I of size |I| is either an interval of size 1 or a common (resp. conserved) interval that contains another b-nested common (resp. conserved) interval of size at least |I|-b. When b=1, this corresponds to the classical notion of nested interval. We exhibit two simple algorithms to output all b-nested common or conserved intervals between K permutations in O(Kn+nocc) time, where nocc is the total number of such intervals. We also explain how to count all b-nested intervals in O(Kn) time. New properties of the family of conserved intervals are proposed to do so.

  9. Reinforcement value and fixed-interval performance.

    PubMed

    Buriticá, Jonathan; Dos Santos, Cristiano V

    2017-08-29

    The concept of reinforcement value summarizes the effect of different variables, such as reinforcement delay, reinforcement magnitude, and deprivation level, on behavior. In the present set of experiments, we evaluated the effect of reinforcement devaluation on performance under FI schedules. The literature on timing and reinforcement value suggests that devaluation generates longer expected times to reinforcement than the same intervals trained under control conditions. We devalued reinforcement with delay in Experiments 1A, 1B, and 2, and diminished deprivation in Experiments 3A and 3B. Devaluation reduced response rates, increased the number of one-response intervals, and lengthened postreinforcement pauses, but had inconsistent effects on other timing measures such as quarter life and breakpoint. The results of delayed reinforcement and diminished deprivation manipulations are well summarized as reinforcement devaluation effects. These results suggest that devaluation may reduce stimulus control. In addition, we argue that the process by which delayed reinforcement affects behavior might also explain some effects observed in other devaluation procedures through the concept of reinforcement value. © 2017 Society for the Experimental Analysis of Behavior.

  10. Optimal ABC inventory classification using interval programming

    NASA Astrophysics Data System (ADS)

    Rezaei, Jafar; Salimi, Negin

    2015-08-01

    Inventory classification is one of the most important activities in inventory management, whereby inventories are classified into three or more classes. Several inventory classifications have been proposed in the literature, almost all of which have two main shortcomings in common. That is, the previous methods mainly rely on an expert opinion to derive the importance of the classification criteria which results in subjective classification, and they need precise item parameters before implementing the classification. While the problem has been predominantly considered as a multi-criteria, we examine the problem from a different perspective, proposing a novel optimisation model for ABC inventory classification in the form of an interval programming problem. The proposed interval programming model has two important features compared to the existing methods: it provides optimal results instead of an expert-based classification and it does not require precise values of item parameters, which are not almost always available before classification. Finally, by illustrating the proposed classification model in the form of numerical example, conclusion and suggestions for future works are presented.

  11. Neurocomputational Models of Interval and Pattern Timing

    PubMed Central

    Hardy, Nicholas F.; Buonomano, Dean V.

    2016-01-01

    Most of the computations and tasks performed by the brain require the ability to tell time, and process and generate temporal patterns. Thus, there is a diverse set of neural mechanisms in place to allow the brain to tell time across a wide range of scales: from interaural delays on the order of microseconds to circadian rhythms and beyond. Temporal processing is most sophisticated on the scale of tens of milliseconds to a few seconds, because it is within this range that the brain must recognize and produce complex temporal patterns—such as those that characterize speech and music. Most models of timing, however, have focused primarily on simple intervals and durations, thus it is not clear whether they will generalize to complex pattern-based temporal tasks. Here, we review neurobiologically based models of timing in the subsecond range, focusing on whether they generalize to tasks that require placing consecutive intervals in the context of an overall pattern, that is, pattern timing. PMID:27790629

  12. [Severe craniocerebral injuries with a lucid interval].

    PubMed

    Vilalta, J; Rubio, E; Castaño, C H; Guitart, J M; Bosch, J

    1993-02-01

    Some variables were analyzed in 35 patients with severe cranioencephalic injuries following a lucid interval according to mortality. The variables analyzed were: age of less than 40 years, interval of time accident-admission (TAA), admission-operation (TAO), level of consciousness (Glasgow scale), associated extracranial lesions, type of intracranial lesion, and tomodensitometric signs of intracranial hypertension. The only variables demonstrating significant statistical differences (p < 0.05) were the level of consciousness (Glasgow scale < 6 points) and the presence of subdural hematoma. Twelve (70.5%) patients who died had less than 6 on the Glasgow scale and in contrast only 5 (27.7%) of the living. Eleven (64.7%) of the group who died and 4 (22.2%) of the living had subdural hematoma. These data suggest that the level of consciousness and the type of lesion are determining factors of the mortality in this type of patients. Early detection and energic treatment of secondary lesions contribute to prognostic improvement of cranioencephalic injuries.

  13. Prenatal care and subsequent birth intervals.

    PubMed

    Teitler, Julien O; Das, Dhiman; Kruse, Lakota; Reichman, Nancy E

    2012-03-01

    Prenatal care generally includes contraceptive and health education that may help women to control their subsequent fertility. However, research has not examined whether receipt of prenatal care is associated with subsequent birthspacing. Longitudinally linked birth records from 113,662 New Jersey women who had had a first birth in 1996-2000 were used to examine associations between the timing and adequacy of prenatal care prior to a woman's first birth and the timing of her second birth. Multinomial logistic regression analyses adjusted for social and demographic characteristics, hospital and year of birth. Most women (85%) had initiated prenatal care during the first trimester. Women who had not obtained prenatal care until the second or third trimester, or at all, were more likely than those who had had first-trimester care to have a second child within 18 months, rather than in 18-59 months (odds ratios, 1.2-1.6). Similarly, women whose care had been inadequate were more likely than those who had had adequate care to have a short subsequent birth interval (1.2). The associations were robust to alternative measures of prenatal care and birth intervals, and were strongest for mothers with less than 16 years of education. Providers should capitalize on their limited encounters with mothers who initiate prenatal care late or use it sporadically to ensure that these women receive information about family planning. Copyright © 2012 by the Guttmacher Institute.

  14. Sprint vs. interval training in football.

    PubMed

    Ferrari Bravo, D; Impellizzeri, F M; Rampinini, E; Castagna, C; Bishop, D; Wisloff, U

    2008-08-01

    The aim of this study was to compare the effects of high-intensity aerobic interval and repeated-sprint ability (RSA) training on aerobic and anaerobic physiological variables in male football players. Forty-two participants were randomly assigned to either the interval training group (ITG, 4 x 4 min running at 90 - 95 % of HRmax; n = 21) or repeated-sprint training group (RSG, 3 x 6 maximal shuttle sprints of 40 m; n = 21). The following outcomes were measured at baseline and after 7 weeks of training: maximum oxygen uptake, respiratory compensation point, football-specific endurance (Yo-Yo Intermittent Recovery Test, YYIRT), 10-m sprint time, jump height and power, and RSA. Significant group x time interaction was found for YYIRT (p = 0.003) with RSG showing greater improvement (from 1917 +/- 439 to 2455 +/- 488 m) than ITG (from 1846 +/- 329 to 2077 +/- 300 m). Similarly, a significant interaction was found in RSA mean time (p = 0.006) with only the RSG group showing an improvement after training (from 7.53 +/- 0.21 to 7.37 +/- 0.17 s). No other group x time interactions were found. Significant pre-post changes were found for absolute and relative maximum oxygen uptake and respiratory compensation point (p < 0.05). These findings suggest that the RSA training protocol used in this study can be an effective training strategy for inducing aerobic and football-specific training adaptations.

  15. Pediatric reference intervals for alkaline phosphatase.

    PubMed

    Zierk, Jakob; Arzideh, Farhad; Haeckel, Rainer; Cario, Holger; Frühwald, Michael C; Groß, Hans-Jürgen; Gscheidmeier, Thomas; Hoffmann, Reinhard; Krebs, Alexander; Lichtinghagen, Ralf; Neumann, Michael; Ruf, Hans-Georg; Steigerwald, Udo; Streichert, Thomas; Rascher, Wolfgang; Metzler, Markus; Rauh, Manfred

    2017-01-01

    Interpretation of alkaline phosphatase activity in children is challenging due to extensive changes with growth and puberty leading to distinct sex- and age-specific dynamics. Continuous percentile charts from birth to adulthood allow accurate consideration of these dynamics and seem reasonable for an analyte as closely linked to growth as alkaline phosphatase. However, the ethical and practical challenges unique to pediatric reference intervals have restricted the creation of such percentile charts, resulting in limitations when clinical decisions are based on alkaline phosphatase activity. We applied an indirect method to generate percentile charts for alkaline phosphatase activity using clinical laboratory data collected during the clinical care of patients. A total of 361,405 samples from 124,440 patients from six German tertiary care centers and one German laboratory service provider measured between January 2004 and June 2015 were analyzed. Measurement of alkaline phosphatase activity was performed on Roche Cobas analyzers using the IFCC's photometric method. We created percentile charts for alkaline phosphatase activity in girls and boys from birth to 18 years which can be used as reference intervals. Additionally, data tables of age- and sex-specific percentile values allow the incorporation of these results into laboratory information systems. The percentile charts provided enable the appropriate differential diagnosis of changes in alkaline phosphatase activity due to disease and changes due to physiological development. After local validation, integration of the provided percentile charts into result reporting facilitates precise assessment of alkaline phosphatase dynamics in pediatrics.

  16. Hydrogen atom distribution and hydrogen induced site depopulation for the La{sub 2-x}Mg{sub x}Ni{sub 7}-H system

    SciTech Connect

    Guzik, Matylda N.; Hauback, Bjorn C.; Yvon, Klaus

    2012-02-15

    opposed to nine proposed for La{sub 1.5}Mg{sub 0.5}Ni{sub 7}D{sub 8.9(9.1)}. The reported four remaining deuterium atom positions in La{sub 1.5}Mg{sub 0.5}Ni{sub 7}D{sub 8.9(9.1)} were not found in the investigated La{sub 1.63}Mg{sub 0.37}Ni{sub 7}D{sub 8.8}. The five Ni atoms have deuterium among their nearest neighbors, which surround them in a way similar to configurations observed in some complex transition metal hydrides and already reported for metallic hydrides. In the presented deuterium-rich phase, deformed tetrahedron, rigid trigonal pyramids as well as disordered and deformed saddle-like configuration are observed. Highlights: Black-Right-Pointing-Pointer Alpha- and beta-phase for La{sub 2-x}Mg{sub x}Ni{sub 7}-H system have been characterized. Black-Right-Pointing-Pointer Five different interstitial sites are occupied by deuterium/hydrogen atoms in the beta-phase. Black-Right-Pointing-Pointer One D/H site has been determined in the alpha-phase. Black-Right-Pointing-Pointer Deuterium/hydrogen induced site depopulation during phase transformation is observed. Black-Right-Pointing-Pointer Ni atoms tend to have tetrahedral-like D/H atom coordination.

  17. Serial binary interval ratios improve rhythm reproduction.

    PubMed

    Wu, Xiang; Westanmo, Anders; Zhou, Liang; Pan, Junhao

    2013-01-01

    Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are better discriminated and reproduced than rhythms with hierarchical non-binary ratios. However, it remains unclear whether a superiority of serial binary over non-binary ratios in rhythm perception and reproduction exists. In addition, how different types of serial ratios influence the metrical strength of rhythms remains to be elucidated. The present study investigated serial binary vs. non-binary ratios in a reproduction task. Rhythms formed with exclusively binary (1:2:4:8), non-binary integer (1:3:5:6), and non-integer (1:2.3:5.3:6.4) ratios were examined within a constant meter. The results showed that the 1:2:4:8 rhythm type was more accurately reproduced than the 1:3:5:6 and 1:2.3:5.3:6.4 rhythm types, and the 1:2.3:5.3:6.4 rhythm type was more accurately reproduced than the 1:3:5:6 rhythm type. Further analyses showed that reproduction performance was better predicted by the distribution pattern of event occurrences within an inter-beat interval, than by the coincidence of events with beats, or the magnitude and complexity of interval ratios. Whereas rhythm theories and empirical data emphasize the role of the coincidence of events with beats in determining metrical strength and predicting rhythm performance, the present results suggest that rhythm processing may be better understood when the distribution pattern of event occurrences is taken into account. These results provide new insights into the mechanisms underlining musical rhythm perception.

  18. Serial binary interval ratios improve rhythm reproduction

    PubMed Central

    Wu, Xiang; Westanmo, Anders; Zhou, Liang; Pan, Junhao

    2013-01-01

    Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are better discriminated and reproduced than rhythms with hierarchical non-binary ratios. However, it remains unclear whether a superiority of serial binary over non-binary ratios in rhythm perception and reproduction exists. In addition, how different types of serial ratios influence the metrical strength of rhythms remains to be elucidated. The present study investigated serial binary vs. non-binary ratios in a reproduction task. Rhythms formed with exclusively binary (1:2:4:8), non-binary integer (1:3:5:6), and non-integer (1:2.3:5.3:6.4) ratios were examined within a constant meter. The results showed that the 1:2:4:8 rhythm type was more accurately reproduced than the 1:3:5:6 and 1:2.3:5.3:6.4 rhythm types, and the 1:2.3:5.3:6.4 rhythm type was more accurately reproduced than the 1:3:5:6 rhythm type. Further analyses showed that reproduction performance was better predicted by the distribution pattern of event occurrences within an inter-beat interval, than by the coincidence of events with beats, or the magnitude and complexity of interval ratios. Whereas rhythm theories and empirical data emphasize the role of the coincidence of events with beats in determining metrical strength and predicting rhythm performance, the present results suggest that rhythm processing may be better understood when the distribution pattern of event occurrences is taken into account. These results provide new insights into the mechanisms underlining musical rhythm perception. PMID:23964258

  19. Physiological Responses to High-Intensity Interval Exercise Differing in Interval Duration.

    PubMed

    Tucker, Wesley J; Sawyer, Brandon J; Jarrett, Catherine L; Bhammar, Dharini M; Gaesser, Glenn A

    2015-12-01

    We determined the oxygen uptake (V[Combining Dot Above]O2), heart rate (HR), and blood lactate responses to 2 high-intensity interval exercise protocols differing in interval length. On separate days, 14 recreationally active males performed a 4 × 4 (four 4-minute intervals at 90-95% HRpeak, separated by 3-minute recovery at 50 W) and 16 × 1 (sixteen 1-minute intervals at 90-95% HRpeak, separated by 1-minute recovery at 50 W) protocol on a cycle ergometer. The 4 × 4 elicited a higher mean V[Combining Dot Above]O2 (2.44 ± 0.4 vs. 2.36 ± 0.4 L·min) and "peak" V[Combining Dot Above]O2 (90-99% vs. 76-85% V[Combining Dot Above]O2peak) and HR (95-98% HRpeak vs. 81-95% HRpeak) during the high-intensity intervals. Average power maintained was higher for the 16 × 1 (241 ± 45 vs. 204 ± 37 W), and recovery interval V[Combining Dot Above]O2 and HR were higher during the 16 × 1. No differences were observed for blood lactate concentrations at the midpoint (12.1 ± 2.2 vs. 10.8 ± 3.1 mmol·L) and end (10.6 ± 1.5 vs. 10.6 ± 2.4 mmol·L) of the protocols or ratings of perceived exertion (7.0 ± 1.6 vs. 7.0 ± 1.4) and Physical Activity Enjoyment Scale scores (91 ± 15 vs. 93 ± 12). Despite a 4-fold difference in interval duration that produced greater between-interval transitions in V[Combining Dot Above]O2 and HR and slightly higher mean V[Combining Dot Above]O2 during the 4 × 4, mean HR during each protocol was the same, and both protocols were rated similarly for perceived exertion and enjoyment. The major difference was that power output had to be reduced during the 4 × 4 protocol to maintain the desired HR.

  20. An Empirical Method for Establishing Positional Confidence Intervals Tailored for Composite Interval Mapping of QTL

    PubMed Central

    Love, Tanzy M.

    2010-01-01

    Background Improved genetic resolution and availability of sequenced genomes have made positional cloning of moderate-effect QTL realistic in several systems, emphasizing the need for precise and accurate derivation of positional confidence intervals (CIs) for QTL. Support interval (SI) methods based on the shape of the QTL likelihood curve have proven adequate for standard interval mapping, but have not been shown to be appropriate for use with composite interval mapping (CIM), which is one of the most commonly used QTL mapping methods. Results Based on a non-parametric confidence interval (NPCI) method designed for use with the Haley-Knott regression method for mapping QTL, a CIM-specific method (CIM-NPCI) was developed to appropriately account for the selection of background markers during analysis of bootstrap-resampled data sets. Coverage probabilities and interval widths resulting from use of the NPCI, SI, and CIM-NPCI methods were compared in a series of simulations analyzed via CIM, wherein four genetic effects were simulated in chromosomal regions with distinct marker densities while heritability was fixed at 0.6 for a population of 200 isolines. CIM-NPCIs consistently capture the simulated QTL across these conditions while slightly narrower SIs and NPCIs fail at unacceptably high rates, especially in genomic regions where marker density is high, which is increasingly common for real studies. The effects of a known CIM bias toward locating QTL peaks at markers were also investigated for each marker density case. Evaluation of sub-simulations that varied according to the positions of simulated effects relative to the nearest markers showed that the CIM-NPCI method overcomes this bias, offering an explanation for the improved coverage probabilities when marker densities are high. Conclusions Extensive simulation studies herein demonstrate that the QTL confidence interval methods typically used to positionally evaluate CIM results can be dramatically improved

  1. Estimating entropy rates with Bayesian confidence intervals.

    PubMed

    Kennel, Matthew B; Shlens, Jonathon; Abarbanel, Henry D I; Chichilnisky, E J

    2005-07-01

    The entropy rate quantifies the amount of uncertainty or disorder produced by any dynamical system. In a spiking neuron, this uncertainty translates into the amount of information potentially encoded and thus the subject of intense theoretical and experimental investigation. Estimating this quantity in observed, experimental data is difficult and requires a judicious selection of probabilistic models, balancing between two opposing biases. We use a model weighting principle originally developed for lossless data compression, following the minimum description length principle. This weighting yields a direct estimator of the entropy rate, which, compared to existing methods, exhibits significantly less bias and converges faster in simulation. With Monte Carlo techinques, we estimate a Bayesian confidence interval for the entropy rate. In related work, we apply these ideas to estimate the information rates between sensory stimuli and neural responses in experimental data (Shlens, Kennel, Abarbanel, & Chichilnisky, in preparation).

  2. A primer on confidence intervals in psychopharmacology.

    PubMed

    Andrade, Chittaranjan

    2015-02-01

    Research papers and research summaries frequently present results in the form of data accompanied by 95% confidence intervals (CIs). Not all students and clinicians know how to interpret CIs. This article provides a nontechnical, nonmathematical discussion on how to understand and glean information from CIs; all explanations are accompanied by simple examples. A statistically accurate explanation about CIs is also provided. CIs are differentiated from standard deviations, standard errors, and confidence levels. The interpretation of narrow and wide CIs is discussed. Factors that influence the width of a CI are listed. Explanations are provided for how CIs can be used to assess statistical significance. The significance of overlapping and nonoverlapping CIs is considered. It is concluded that CIs are far more informative than, say, mere P values when drawing conclusions about a result.

  3. Neural Circuitry for Recognizing Interspike Interval Sequences

    NASA Astrophysics Data System (ADS)

    Abarbanel, Henry D. I.; Talathi, Sachin S.

    2006-04-01

    Sensory systems present environmental information to central nervous system as sequences of action potentials or spikes. How do animals recognize these sequences carrying information about their world? We present a biologically inspired neural circuit designed to enable spike pattern recognition. This circuit is capable of training itself on a given interspike interval (ISI) sequence and is then able to respond to presentations of the same sequence. The essential ingredients of the recognition circuit are (a) a tunable time delay circuit, (b) a spike selection unit, and (c) a tuning mechanism using spike timing dependent plasticity of inhibitory synapses. We have investigated this circuit using Hodgkin-Huxley neuron models connected by realistic excitatory and inhibitory synapses. It is robust in the presence of noise represented as jitter in the spike times of the ISI sequence.

  4. How do I interpret a confidence interval?

    PubMed

    O'Brien, Sheila F; Yi, Qi Long

    2016-07-01

    A 95% confidence interval (CI) of the mean is a range with an upper and lower number calculated from a sample. Because the true population mean is unknown, this range describes possible values that the mean could be. If multiple samples were drawn from the same population and a 95% CI calculated for each sample, we would expect the population mean to be found within 95% of these CIs. CIs are sensitive to variability in the population (spread of values) and sample size. When used to compare the means of two or more treatment groups, a CI shows the magnitude of a difference between groups. This is helpful in understanding both the statistical significance and the clinical significance of a treatment. In this article we describe the basic principles of CIs and their interpretation.

  5. Representing spike trains using constant sampling intervals.

    PubMed

    Hirata, Yoshito; Aihara, Kazuyuki

    2009-10-15

    Sensory neurons encode external information by a series of times of action potentials, which is called a spike train. However, since it is a point process, it is hard to analyze. Here we propose a method for converting a spike train into a real-valued time series with a fixed sampling interval under the assumption of temporal codes. The proposed method yields time series that represent encoded signals. Especially when the method is applied to spike trains generated using integrate-and-fire models, the yielded time series look very similar to those of encoded information. The method works robustly even when a spike train is contaminated with noise. Since unlike filters it does not use its original signals for the conversion, the proposed method can be widely used for investigating spike train data in the real world.

  6. Short interval testing of solar cells

    NASA Technical Reports Server (NTRS)

    Saylor, C. R.; Lathrop, J. W.

    1981-01-01

    A drawback of conventional electrical evaluation procedures regarding solar cells is related to time consuming operations required in the determination of specific parameters, such as the maximum power point, from the plotted curves, and to the transfer of data to a large digital computer for analysis and manipulation. This is especially true when large numbers of cells must be measured. To overcome such drawbacks, a digital short interval tester was designed and constructed. The new tester provides rapid and accurate measurements at constant temperature. The utilization of a light shutter makes it possible to measure up to 200 data points along the I-V curve in less than a second, thus avoiding thermal effects. Because the system is digital, parameters such as the maximum power may be calculated directly from the data.

  7. On the convergence of validity interval analysis.

    PubMed

    Maire, F

    2000-01-01

    Validity interval analysis (VIA) is a generic tool for analyzing the input-output behavior of feedforward neural networks. VIA is a rule extraction technique that relies on a rule refinement algorithm. The rules are of the form R(i)-->R(0) which reads if the input of the neural network is in the region R(i), then its output is in the region R(0), where regions are axis parallel hypercubes. VIA conjectures, then refines and checks rules for inconsistency. This process can be computationally expensive, and the rule refinement phase becomes critical. Hence, the importance of knowing the complexity of these rule refinement algorithms. In this paper, we show that the rule refinement part of VIA always converges in one run for single-weight-layer networks, and has an exponential average rate of convergence for multilayer networks. We also discuss some variations of the standard VIA formulae.

  8. Prenatal Care and Subsequent Birth Intervals

    PubMed Central

    Teitler, Julien O.; Das, Dhiman; Kruse, Lakota; Reichman, Nancy E.

    2013-01-01

    Context Research on the effectiveness of prenatal care has focused primarily on birth outcomes, finding small effects at the population level. However, prenatal care generally includes postpartum contraceptive and health education that may enable women to better control their subsequent fertility. Associations between prenatal care and subsequent fertility have not been previously explored. Methods Using longitudinally-linked birth records from New Jersey between 1996 and 2006, we estimated multinomial logistic regression models to investigate associations between prenatal care (timing or adequacy) in a mother’s first birth and timing of her second birth, controlling for sociodemographic characteristics and hospital and year of birth. Results Most mothers initiated prenatal care in the first (85%) or second (12%) trimester. Initiation of care after the first trimester is strongly associated with short subsequent birth intervals. The odds of having a second child in fewer than 18 months (compared to 18–59 months) were 19% higher if the mother initiated care in the second versus the first trimester, 26% higher if she initiated care in the third trimester, and 61% higher if she did not receive any care, all else equal. The associations are robust to alternative measures of prenatal care and birth intervals and are stronger for mothers with low levels of education. Conclusions The findings suggest that prenatal providers should capitalize on their limited encounters with mothers who initiate prenatal care late or use it sporadically to make information about family planning available. This issue is timely given recent and proposed budget cuts to public family planning. PMID:22405147

  9. Lutein ester profile in wheat and tritordeum can be modulated by temperature: Evidences for regioselectivity and fatty acid preferential of enzymes encoded by genes on chromosomes 7D and 7H(ch).

    PubMed

    Mattera, M G; Hornero-Méndez, D; Atienza, S G

    2017-03-15

    The increase of lutein retention through the food chain is desirable for wheat breeding. Lutein esters are more stable than free lutein during post-harvest storage and two loci on chromosomes 7D and 7H(ch) are important for esterification. We investigated the effect of temperature during grain filling on carotenoid accumulation and lutein ester profile including fatty acid selectivity (palmitic vs. linoleic) and regioselectivity (esterification at positions 3 vs. 3'). Three different temperature regimes were assayed (controlled, semi-controlled and non-controlled). Lutein esters were more stable than free carotenoids in vivo and the enzymes encoded by chromosomes 7H(ch) and 7D are complementary. Indeed, they show differential preferences for the fatty acid (palmitic and linoleic, respectively) and regioselectivity (3 and 3', respectively). Besides, H. chilense has additional genes for esterification. Finally, the increase of temperature favoured the accumulation of lutein esters with linoleic acid and the synthesis of regioisomers at position 3'.

  10. 7-cyclopentyl-5-(4-phenoxyphenyl)-7H-pyrrolo[2,3-d] pyrimidin-4-ylamine inhibits the proliferation and migration of vascular smooth muscle cells by suppressing ERK and Akt pathways.

    PubMed

    Seo, Hyang-Hee; Kim, Sang Woo; Lee, Chang Youn; Lim, Kyu Hee; Lee, Jiyun; Lim, Soyeon; Lee, Seahyoung; Hwang, Ki-Chul

    2017-03-05

    Excessive vascular smooth muscle cell (VSMC) proliferation and migration after vascular injury significantly contributes to the development of occlusive vascular disease. Therefore, inhibiting the proliferation and migration of VSMCs is a validated therapeutic modality for occlusive vascular disease such as atherosclerosis and restenosis. In the present study, we screened chemical compounds for their anti-proliferative effects on VSMCs using multiple approaches, such as MTT assays, wound healing assays, and trans-well migration assays. Our data indicate that 7-cyclopentyl-5-(4-phenoxyphenyl)-7H-pyrrolo[2,3-d] pyrimidin-4-ylamine, a lymphocyte-specific protein tyrosine kinase (Lck) inhibitor, significantly inhibited both VSMC proliferation and migration. 7-cyclopentyl-5-(4-phenoxyphenyl)-7H-pyrrolo[2,3-d]pyrimidin-4-ylamine suppresses VSMC proliferation and migration via down-regulating the protein kinase B (Akt) and extracellular signal regulated kinase (ERK) pathways, and it significantly decreased the expression of proliferating cell nuclear antigen (PCNA) and cyclin D1 and, the phosphorylation of retinoblastoma protein (pRb). Additionally, 7-cyclopentyl-5-(4-phenoxyphenyl)-7H-pyrrolo[2,3-d] pyrimidin-4-ylamine suppressed the migration of VSMCs from endothelium-removed aortic rings, as well as neointima formation following rat carotid balloon injury. The present study identified 7-cyclopentyl-5-(4-phenoxyphenyl)-7H-pyrrolo[2,3-d]pyrimidin-4-ylamine as a potent VSMC proliferation and migration inhibitor and warrants further studies to elucidate its more detailed molecular mechanisms, such as its primary target, and to further validate its in vivo efficacy as a therapeutic agent for pathologic vascular conditions, such as restenosis and atherosclerosis. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Tetrahedral-Atom 3-Ring Groupings in One-Dimensional Inorganic Chains: Be2AsO4OH-4H2O and Na2ZnPO4OH-7H2O

    DTIC Science & Technology

    1993-02-15

    connections. Adjacent stacks are interconnected vio a complex arrangement of sodium cations and water molecules. I&. SUBJECT TERMS 15. NUMBER OF PAGES...rings which include Zn-(OH)-Zn connections. Adjacent stacks are interconnected via a complex arrangement of sodium cations and water molecules. MTrC...above paragraph, we describe the preparations, structures and properties of two new phases; a zincophosphate , Na2ZnPO 4OH-7H 20 (NaZnPO), and a

  12. Confidence Intervals Make a Difference: Effects of Showing Confidence Intervals on Inferential Reasoning

    ERIC Educational Resources Information Center

    Hoekstra, Rink; Johnson, Addie; Kiers, Henk A. L.

    2012-01-01

    The use of confidence intervals (CIs) as an addition or as an alternative to null hypothesis significance testing (NHST) has been promoted as a means to make researchers more aware of the uncertainty that is inherent in statistical inference. Little is known, however, about whether presenting results via CIs affects how readers judge the…

  13. Confidence Intervals Make a Difference: Effects of Showing Confidence Intervals on Inferential Reasoning

    ERIC Educational Resources Information Center

    Hoekstra, Rink; Johnson, Addie; Kiers, Henk A. L.

    2012-01-01

    The use of confidence intervals (CIs) as an addition or as an alternative to null hypothesis significance testing (NHST) has been promoted as a means to make researchers more aware of the uncertainty that is inherent in statistical inference. Little is known, however, about whether presenting results via CIs affects how readers judge the…

  14. Pigeons' Memory for Number of Events: Effects of Intertrial Interval and Delay Interval Illumination

    ERIC Educational Resources Information Center

    Hope, Chris; Santi, Angelo

    2004-01-01

    In Experiment 1, pigeons were trained at a 0-s baseline delay to discriminate sequences of light flashes (illumination of the feeder) that varied in number but not time (2f/4s and 8f/4s). During training, the intertrial interval was illuminated by the houselight for Group Light, but it was dark for Group Dark. Testing conducted with dark delay…

  15. Detections of Long Carbon Chains CH_{3}CCCCH, C_{6}H, LINEAR-C_{6}H_{2} and C_{7}H in the Low-Mass Star Forming Region L1527

    NASA Astrophysics Data System (ADS)

    Araki, Mitsunori; Takano, Shuro; Sakai, Nami; Yamamoto, Satoshi; Oyama, Takahiro; Kuze, Nobuhiko; Tsukiyama, Koichi

    2017-06-01

    Carbon chains in the warm carbon chain chemistry (WCCC) region has been searched in the 42-44 GHz region by using Green Bank 100 m telescope. Long carbon chains C_{7}H, C_{6}H, CH_{3}CCCCH, and linear-C_{6}H_{2} and cyclic species C_{3}H and C_{3}H_{2}O have been detected in the low-mass star forming region L1527, performing the WCCC. C_{7}H was detected for the first time in molecular clouds. The column density of C_{7}H is derived to be 6.2 × 10^{10} cm^{-2} by using the detected J = 24.5-23.5 and 25.5-24.5 rotational lines. The ^{2}Π_{1/2} electronic state of C_{6}H, locating 21.6 K above the ^{2}Π_{3/2} electronic ground state, and the K_a = 0 line of the para species of linear-C_{6}H_{2} were also detected firstly in molecular clouds. The column densities of the ^{2}Π_{1/2} and ^{2}Π_{3/2} states of C_{6}H in L1527 were derived to be 1.6 × 10^{11} and 1.1 × 10^{12} cm^{-2}, respectively. The total column density of linear-C_{6}H_{2} is obtained to be 1.86 × 10^{11} cm^{-2}. While the abundance ratios of carbon chains in between L1527 and the starless dark cloud Taurus Molecular Cloud-1 Cyanopolyyne Peak (TMC-1 CP) have a trend of decrease by extension of carbon-chain length, column densities of CH_{3}CCCCH and C_{6}H are on the trend. However, the column densities of linear-C_{6}H_{2}, and C_{7}H are as abundant as those of TMC-1 CP in spite of long carbon chain, i.e., they are not on the trend. The abundances of linear-C_{6}H_{2} and C_{7}H show that L1527 is rich for long carbon chains as well as TMC-1 CP.

  16. Safety and Biodistribution Evaluation in Cynomolgus Macaques of rAAV2tYF-PR1.7-hCNGB3, a Recombinant AAV Vector for Treatment of Achromatopsia.

    PubMed

    Ye, Guo-jie; Budzynski, Ewa; Sonnentag, Peter; Nork, T Michael; Miller, Paul E; Sharma, Alok K; Ver Hoeve, James N; Smith, Leia M; Arndt, Tara; Calcedo, Roberto; Gaskin, Chantelle; Robinson, Paulette M; Knop, David R; Hauswirth, William W; Chulay, Jeffrey D

    2016-03-01

    Applied Genetic Technologies Corporation (AGTC) is developing rAAV2tYF-PR1.7-hCNGB3, a recombinant adeno-associated viral (rAAV) vector expressing the human CNGB3 gene, for treatment of achromatopsia, an inherited retinal disorder characterized by markedly reduced visual acuity, extreme light sensitivity, and absence of color discrimination. We report here results of a study evaluating the safety and biodistribution of rAAV2tYF-PR1.7-hCNGB3 in cynomolgus macaques. Three groups of animals (n = 2 males and 2 females per group) received a subretinal injection in one eye of 300 μl containing either vehicle or rAAV2tYF-PR1.7-hCNGB3 at one of two concentrations (4 × 10(11) or 4 × 10(12) vector genomes/ml) and were evaluated over a 3-month period before being euthanized. Administration of rAAV2tYF-PR1.7-hCNGB3 was associated with a dose-related anterior and posterior segment inflammatory response that was greater than that observed in eyes injected with the vehicle control. Most manifestations of inflammation improved over time except that vitreous cells persisted in vector-treated eyes until the end of the study. One animal in the lower vector dose group was euthanized on study day 5, based on a clinical diagnosis of endophthalmitis. There were no test article-related effects on intraocular pressure, visual evoked potential responses, hematology or clinical chemistry parameters, or gross necropsy observations. Histopathological examination demonstrated minimal mononuclear infiltrates in all vector-injected eyes. Serum anti-AAV antibodies developed in all vector-injected animals. No animals developed antibodies to CNGB3. Biodistribution studies demonstrated high levels of vector DNA in the injected eye but minimal or no vector DNA in any other tissue. These results support the use of rAAV2tYF-PR1.7-hCNGB3 in clinical studies in patients with achromatopsia caused by CNGB3 mutations.

  17. Safety and Biodistribution Evaluation in Cynomolgus Macaques of rAAV2tYF-PR1.7-hCNGB3, a Recombinant AAV Vector for Treatment of Achromatopsia.

    PubMed

    Ye, Guo-Jie; Budzynski, Ewa; Sonnentag, Peter; Nork, T Michael; Miller, Paul E; Sharma, Alok K; Ver Hoeve, James N; Smith, Leia; Arndt, Tara; Calcedo, Roberto; Gaskin, Chantelle; Robinson, Paulette; Knop, David R; Hauswirth, William W; Chulay, Jeffrey David

    2016-03-08

    AGTC is developing rAAV2tYF-PR1.7-hCNGB3, a recombinant adeno-associated virus (rAAV) vector expressing the human CNGB3 gene, for treatment of achromatopsia, an inherited retinal disorder characterized by markedly reduced visual acuity, extreme light sensitivity and absence of color discrimination. We report here results of a study evaluating the safety and biodistribution of rAAV2tYF-PR1.7-hCNGB3 in cynomolgus macaques. Three groups of animals (n=2 males and 2 females per group) received a subretinal injection in one eye of 300 µL containing either vehicle or rAAV2tYF-PR1.7-hCNGB3 at one of two concentrations (4 × 1011 or 4 × 1012 vg/mL) and were evaluated over a 3 month period prior to being euthanized. Administration of rAAV2tYF-PR1.7-hCNGB3 was associated with a dose-related anterior and posterior segment inflammatory response that was greater than that observed in eyes injected with the vehicle control. Most manifestations of inflammation improved over time except that vitreous cells persisted in vector-treated eyes until the end of the study. One animal in the lower vector dose group was euthanized on Study Day 5 based on a clinical diagnosis of endophthalmitis. There were no test article-related effects on intraocular pressure, visual evoked potential responses, hematology or clinical chemistry parameters, or gross necropsy observations. Histopathological examination demonstrated minimal mononuclear infiltrates in all vector-injected eyes. Serum anti-AAV antibodies developed in all vector-injected animals. No animals developed antibodies to CNGB3. Biodistribution studies demonstrated high levels of vector DNA in the injected eye but minimal or no vector DNA in any other tissue. These results support the use of rAAV2tYF-PR1.7-hCNGB3 in clinical studies in patients with achromatopsia caused by CNGB3 mutations.

  18. Safety and Biodistribution Evaluation in Cynomolgus Macaques of rAAV2tYF-PR1.7-hCNGB3, a Recombinant AAV Vector for Treatment of Achromatopsia

    PubMed Central

    Ye, Guo-jie; Budzynski, Ewa; Sonnentag, Peter; Nork, T. Michael; Miller, Paul E.; Sharma, Alok K.; Ver Hoeve, James N.; Smith, Leia M.; Arndt, Tara; Calcedo, Roberto; Gaskin, Chantelle; Robinson, Paulette M.; Knop, David R.; Hauswirth, William W.; Chulay, Jeffrey D.

    2016-01-01

    Applied Genetic Technologies Corporation (AGTC) is developing rAAV2tYF-PR1.7-hCNGB3, a recombinant adeno-associated viral (rAAV) vector expressing the human CNGB3 gene, for treatment of achromatopsia, an inherited retinal disorder characterized by markedly reduced visual acuity, extreme light sensitivity, and absence of color discrimination. We report here results of a study evaluating the safety and biodistribution of rAAV2tYF-PR1.7-hCNGB3 in cynomolgus macaques. Three groups of animals (n = 2 males and 2 females per group) received a subretinal injection in one eye of 300 μl containing either vehicle or rAAV2tYF-PR1.7-hCNGB3 at one of two concentrations (4 × 1011 or 4 × 1012 vector genomes/ml) and were evaluated over a 3-month period before being euthanized. Administration of rAAV2tYF-PR1.7-hCNGB3 was associated with a dose-related anterior and posterior segment inflammatory response that was greater than that observed in eyes injected with the vehicle control. Most manifestations of inflammation improved over time except that vitreous cells persisted in vector-treated eyes until the end of the study. One animal in the lower vector dose group was euthanized on study day 5, based on a clinical diagnosis of endophthalmitis. There were no test article-related effects on intraocular pressure, visual evoked potential responses, hematology or clinical chemistry parameters, or gross necropsy observations. Histopathological examination demonstrated minimal mononuclear infiltrates in all vector-injected eyes. Serum anti-AAV antibodies developed in all vector-injected animals. No animals developed antibodies to CNGB3. Biodistribution studies demonstrated high levels of vector DNA in the injected eye but minimal or no vector DNA in any other tissue. These results support the use of rAAV2tYF-PR1.7-hCNGB3 in clinical studies in patients with achromatopsia caused by CNGB3 mutations. PMID:27003753

  19. Interval Estimation of the Population Squared Multiple Correlation

    ERIC Educational Resources Information Center

    Pohlmann, John T.; Moore, James F.

    1977-01-01

    A technique is presented which applies the Neyman theory of confidence intervals to interval estimation of the squared multiple correlation coefficient. A computer program is presented which can be used to apply the technique. (Author/JKS)

  20. A survey of Australian haematology reference intervals.

    PubMed

    Sinclair, Leanne; Hall, Sara; Badrick, Tony

    2014-10-01

    This study was designed to create a snapshot of Australian haematology reference intervals (RIs) in use, in particular red cell parameters. We present an analysis of survey results conducted across Australian laboratories between November 2012 and January 2013.All Australian laboratories enrolled in the Royal College of Pathologists of Australasia Quality Assurance Program (RCPA QAP) were invited to participate in the December 2012 Survey Monkey survey, with a response from 85 laboratories (17%) received. The scope included laboratory demographics (location, size/throughput, and network), RIs in use for the full blood count and selected derived parameters, their frequency of revision, source and statistical approach for derivation. Further questions related to uncertainty of measurement, pregnancy values, paediatric/adult cut-off, haematology profiles reported and the use of extended parameters.There is more consistency with some upper and lower limits than others, and wide ranges for reported uncertainty of measurement (UM). There is no apparent consistency with RIs used for particular instruments and technologies. When laboratories change their RIs, most obtain them from a text book, paper or another laboratory and have difficulty in determining the source. If they do determine their own, most don't have a standard operating procedure and calculations are not consistent in terms of sample size and statistical methods used.We have presented evidence of the wide variations in RIs used in Australian laboratories and that arguably these do not differ significantly from each other. The paediatric age cut-off requires standardisation.

  1. Interval bisection in spontaneously hypertensive rats.

    PubMed

    Orduña, Vladimir; Hong, Enrique; Bouzas, Arturo

    2007-01-10

    An interval bisection procedure was used to study time discrimination in spontaneously hypertensive rats (SHR), which have been proposed as an animal model for the attention deficit hyperactivity disorder (ADHD); Wistar Kyoto and Wistar rats were used as comparison groups. In this procedure, after subjects learn to make one response (S) following a short duration stimulus, and another (L) following a long duration stimulus, stimuli of intermediate durations are presented, and the percentage of L is calculated for each duration. A logistic function is fitted to these data, and different parameters that describe the time discrimination process are obtained. Four conditions, with different short and long durations (1-4, 2-8, 3-12, 4-16s) were used. The results indicate that time discrimination is not altered in SHR, given that no difference in any of the parameters obtained were significant. Given that temporal processing has been proposed as a fundamental factor in the development of the main symptoms of ADHD, and that deficits in time discrimination have been found in individuals with that disorder, the present results suggest the necessity of exploring time perception in SHR with other procedures and sensory modalities, in order to assess its validity as an animal model of ADHD.

  2. The Interval approach to braneworld gravity

    SciTech Connect

    Carena, Marcela; Lykken, Joseph D.; Park, Minjoon; /Chicago U., EFI

    2005-06-01

    Gravity in five-dimensional braneworld backgrounds may exhibit extra scalar degrees of freedom with problematic features, including kinetic ghosts and strong coupling behavior. Analysis of such effects is hampered by the standard heuristic approaches to braneworld gravity, which use the equations of motion as the starting point, supplemented by orbifold projections and junction conditions. Here we develop the interval approach to braneworld gravity, which begins with an action principle. This shows how to implement general covariance, despite allowing metric fluctuations that do not vanish on the boundaries. We reproduce simple Z{sub 2} orbifolds of gravity, even though in this approach we never perform a Z{sub 2} projection. We introduce a family of ''straight gauges'', which are bulk coordinate systems in which both branes appear as straight slices in a single coordinate patch. Straight gauges are extremely useful for analyzing metric fluctuations in braneworld models. By explicit gauge fixing, we show that a general AdS{sub 5}/AdS{sub 4} setup with two branes has at most a radion, but no physical ''brane-bending'' modes.

  3. An Investigation of Interval Management Displays

    NASA Technical Reports Server (NTRS)

    Swieringa, Kurt A.; Wilson, Sara R.; Shay, Rick

    2015-01-01

    NASA's first Air Traffic Management (ATM) Technology Demonstration (ATD-1) was created to transition the most mature ATM technologies from the laboratory to the National Airspace System. One selected technology is Interval Management (IM), which uses onboard aircraft automation to compute speeds that help the flight crew achieve and maintain precise spacing behind a preceding aircraft. Since ATD-1 focuses on a near-term environment, the ATD-1 flight demonstration prototype requires radio voice communication to issue an IM clearance. Retrofit IM displays will enable pilots to both enter information into the IM avionics and monitor IM operation. These displays could consist of an interface to enter data from an IM clearance and also an auxiliary display that presents critical information in the primary field-of-view. A human-in-the-loop experiment was conducted to examine usability and acceptability of retrofit IM displays, which flight crews found acceptable. Results also indicate the need for salient alerting when new speeds are generated and the desire to have a primary field of view display available that can display text and graphic trend indicators.

  4. Statistical coding and decoding of heartbeat intervals.

    PubMed

    Lucena, Fausto; Barros, Allan Kardec; Príncipe, José C; Ohnishi, Noboru

    2011-01-01

    The heart integrates neuroregulatory messages into specific bands of frequency, such that the overall amplitude spectrum of the cardiac output reflects the variations of the autonomic nervous system. This modulatory mechanism seems to be well adjusted to the unpredictability of the cardiac demand, maintaining a proper cardiac regulation. A longstanding theory holds that biological organisms facing an ever-changing environment are likely to evolve adaptive mechanisms to extract essential features in order to adjust their behavior. The key question, however, has been to understand how the neural circuitry self-organizes these feature detectors to select behaviorally relevant information. Previous studies in computational perception suggest that a neural population enhances information that is important for survival by minimizing the statistical redundancy of the stimuli. Herein we investigate whether the cardiac system makes use of a redundancy reduction strategy to regulate the cardiac rhythm. Based on a network of neural filters optimized to code heartbeat intervals, we learn a population code that maximizes the information across the neural ensemble. The emerging population code displays filter tuning proprieties whose characteristics explain diverse aspects of the autonomic cardiac regulation, such as the compromise between fast and slow cardiac responses. We show that the filters yield responses that are quantitatively similar to observed heart rate responses during direct sympathetic or parasympathetic nerve stimulation. Our findings suggest that the heart decodes autonomic stimuli according to information theory principles analogous to how perceptual cues are encoded by sensory systems.

  5. Statistical Coding and Decoding of Heartbeat Intervals

    PubMed Central

    Lucena, Fausto; Barros, Allan Kardec; Príncipe, José C.; Ohnishi, Noboru

    2011-01-01

    The heart integrates neuroregulatory messages into specific bands of frequency, such that the overall amplitude spectrum of the cardiac output reflects the variations of the autonomic nervous system. This modulatory mechanism seems to be well adjusted to the unpredictability of the cardiac demand, maintaining a proper cardiac regulation. A longstanding theory holds that biological organisms facing an ever-changing environment are likely to evolve adaptive mechanisms to extract essential features in order to adjust their behavior. The key question, however, has been to understand how the neural circuitry self-organizes these feature detectors to select behaviorally relevant information. Previous studies in computational perception suggest that a neural population enhances information that is important for survival by minimizing the statistical redundancy of the stimuli. Herein we investigate whether the cardiac system makes use of a redundancy reduction strategy to regulate the cardiac rhythm. Based on a network of neural filters optimized to code heartbeat intervals, we learn a population code that maximizes the information across the neural ensemble. The emerging population code displays filter tuning proprieties whose characteristics explain diverse aspects of the autonomic cardiac regulation, such as the compromise between fast and slow cardiac responses. We show that the filters yield responses that are quantitatively similar to observed heart rate responses during direct sympathetic or parasympathetic nerve stimulation. Our findings suggest that the heart decodes autonomic stimuli according to information theory principles analogous to how perceptual cues are encoded by sensory systems. PMID:21694763

  6. Cost effective mass standard calibration intervals

    SciTech Connect

    Shull, A.H.; Clark, J.P.

    1995-11-01

    National Institute of Standards and Technology (NIST) traceable standard weights serve as the foundation of mass measurement control programs. These standards are normally recalibrated annually at a cost of approximately $100 per weight. The Savannah River Site (SRS) has more than 4,000 standard weights. Most have recalibration intervals of 1 year. The cost effectiveness of the current practice was questioned. Are these mass standards being calibrated too often, and are all of these standards needed for calibration and QC activities? Statistical analyses of data from the calibration histories were performed on a random sample of eight weight sets. The analyses indicated no time effects or significant trends in the weight masses for periods of from 5 to 8 years. In other words, calibration checks were being performed too frequently. In addition, current electronic balance technology does not require a traditional set of standard weights that cover the entire weighing range of a balance. At the most, only 2 or 3 standards are needed for most weighing systems. Hence, by increasing weight set recalibration frequencies from 1 to 3 years, and by reducing the number standards calibrated by 80%, annual cost savings of over $400,000 are attainable at SRS. Details of the data analysis, technological advances, and cost savings are included in the paper.

  7. A bedr way of genomic interval processing.

    PubMed

    Haider, Syed; Waggott, Daryl; Lalonde, Emilie; Fung, Clement; Liu, Fei-Fei; Boutros, Paul C

    2016-01-01

    Next-generation sequencing is making it critical to robustly and rapidly handle genomic ranges within standard pipelines. Standard use-cases include annotating sequence ranges with gene or other genomic annotation, merging multiple experiments together and subsequently quantifying and visualizing the overlap. The most widely-used tools for these tasks work at the command-line (e.g. BEDTools) and the small number of available R packages are either slow or have distinct semantics and features from command-line interfaces. To provide a robust R-based interface to standard command-line tools for genomic coordinate manipulation, we created bedr. This open-source R package can use either BEDTools or BEDOPS as a back-end and performs data-manipulation extremely quickly, creating R data structures that can be readily interfaced with existing computational pipelines. It includes data-visualization capabilities and a number of data-access functions that interface with standard databases like UCSC and COSMIC. bedr package provides an open source solution to enable genomic interval data manipulation and restructuring in R programming language which is commonly used in bioinformatics, and therefore would be useful to bioinformaticians and genomic researchers.

  8. Function approximation using adaptive and overlapping intervals

    SciTech Connect

    Patil, R.B.

    1995-05-01

    A problem common to many disciplines is to approximate a function given only the values of the function at various points in input variable space. A method is proposed for approximating a function of several to one variable. The model takes the form of weighted averaging of overlapping basis functions defined over intervals. The number of such basis functions and their parameters (widths and centers) are automatically determined using given training data and a learning algorithm. The proposed algorithm can be seen as placing a nonuniform multidimensional grid in the input domain with overlapping cells. The non-uniformity and overlap of the cells is achieved by a learning algorithm to optimize a given objective function. This approach is motivated by the fuzzy modeling approach and a learning algorithms used for clustering and classification in pattern recognition. The basics of why and how the approach works are given. Few examples of nonlinear regression and classification are modeled. The relationship between the proposed technique, radial basis neural networks, kernel regression, probabilistic neural networks, and fuzzy modeling is explained. Finally advantages and disadvantages are discussed.

  9. High-intensity interval training: Modulating interval duration in overweight/obese men

    PubMed Central

    Smith-Ryan, Abbie E.; Melvin, Malia N.; Wingfield, Hailee L.

    2015-01-01

    Introduction High-intensity interval training (HIIT) is a time-efficient strategy shown to induce various cardiovascular and metabolic adaptations. Little is known about the optimal tolerable combination of intensity and volume necessary for adaptations, especially in clinical populations. Objectives In a randomized controlled pilot design, we evaluated the effects of two types of interval training protocols, varying in intensity and interval duration, on clinical outcomes in overweight/obese men. Methods Twenty-five men [body mass index (BMI) > 25 kg·m2] completed baseline body composition measures: fat mass (FM), lean mass (LM) and percent body fat (%BF) and fasting blood glucose, lipids and insulin (IN). A graded exercise cycling test was completed for peak oxygen consumption (VO2peak) and power output (PO). Participants were randomly assigned to high-intensity short interval (1MIN-HIIT), high-intensity interval (2MIN-HIIT) or control groups. 1MIN-HIIT and 2MIN-HIIT completed 3 weeks of cycling interval training, 3 days/week, consisting of either 10 × 1 min bouts at 90% PO with 1 min rests (1MIN-HIIT) or 5 × 2 min bouts with 1 min rests at undulating intensities (80%–100%) (2MIN-HIIT). Results There were no significant training effects on FM (Δ1.06 ± 1.25 kg) or %BF (Δ1.13% ± 1.88%), compared to CON. Increases in LM were not significant but increased by 1.7 kg and 2.1 kg for 1MIN and 2MIN-HIIT groups, respectively. Increases in VO2peak were also not significant for 1MIN (3.4 ml·kg−1·min−1) or 2MIN groups (2.7 ml·kg−1·min−1). IN sensitivity (HOMA-IR) improved for both training groups (Δ −2.78 ± 3.48 units; p < 0.05) compared to CON. Conclusion HIIT may be an effective short-term strategy to improve cardiorespiratory fitness and IN sensitivity in overweight males. PMID:25913937

  10. High-intensity interval training: Modulating interval duration in overweight/obese men.

    PubMed

    Smith-Ryan, Abbie E; Melvin, Malia N; Wingfield, Hailee L

    2015-05-01

    High-intensity interval training (HIIT) is a time-efficient strategy shown to induce various cardiovascular and metabolic adaptations. Little is known about the optimal tolerable combination of intensity and volume necessary for adaptations, especially in clinical populations. In a randomized controlled pilot design, we evaluated the effects of two types of interval training protocols, varying in intensity and interval duration, on clinical outcomes in overweight/obese men. Twenty-five men [body mass index (BMI) > 25 kg · m(2)] completed baseline body composition measures: fat mass (FM), lean mass (LM) and percent body fat (%BF) and fasting blood glucose, lipids and insulin (IN). A graded exercise cycling test was completed for peak oxygen consumption (VO2peak) and power output (PO). Participants were randomly assigned to high-intensity short interval (1MIN-HIIT), high-intensity interval (2MIN-HIIT) or control groups. 1MIN-HIIT and 2MIN-HIIT completed 3 weeks of cycling interval training, 3 days/week, consisting of either 10 × 1 min bouts at 90% PO with 1 min rests (1MIN-HIIT) or 5 × 2 min bouts with 1 min rests at undulating intensities (80%-100%) (2MIN-HIIT). There were no significant training effects on FM (Δ1.06 ± 1.25 kg) or %BF (Δ1.13% ± 1.88%), compared to CON. Increases in LM were not significant but increased by 1.7 kg and 2.1 kg for 1MIN and 2MIN-HIIT groups, respectively. Increases in VO2peak were also not significant for 1MIN (3.4 ml·kg(-1) · min(-1)) or 2MIN groups (2.7 ml · kg(-1) · min(-1)). IN sensitivity (HOMA-IR) improved for both training groups (Δ-2.78 ± 3.48 units; p < 0.05) compared to CON. HIIT may be an effective short-term strategy to improve cardiorespiratory fitness and IN sensitivity in overweight males.

  11. Overestimation of the second time interval replaces time-shrinking when the difference between two adjacent time intervals increases.

    PubMed

    Nakajima, Yoshitaka; Hasuo, Emi; Yamashita, Miki; Haraguchi, Yuki

    2014-01-01

    When the onsets of three successive sound bursts mark two adjacent time intervals, the second time interval can be underestimated when it is physically longer than the first time interval by up to 100 ms. This illusion, time-shrinking, is very stable when the first time interval is 200 ms or shorter (Nakajima et al., 2004, Perception, 33). Time-shrinking had been considered a kind of perceptual assimilation to make the first and the second time interval more similar to each other. Here we investigated whether the underestimation of the second time interval was replaced by an overestimation if the physical difference between the neighboring time intervals was too large for the assimilation to take place; this was a typical situation in which a perceptual contrast could be expected. Three experiments to measure the overestimation/underestimation of the second time interval by the method of adjustment were conducted. The first time interval was varied from 40 to 280 ms, and such overestimations indeed took place when the first time interval was 80-280 ms. The overestimations were robust when the second time interval was longer than the first time interval by 240 ms or more, and the magnitude of the overestimation was larger than 100 ms in some conditions. Thus, a perceptual contrast to replace time-shrinking was established. An additional experiment indicated that this contrast did not affect the perception of the first time interval substantially: The contrast in the present conditions seemed unilateral.

  12. About Hemispheric Differences in the Processing of Temporal Intervals

    ERIC Educational Resources Information Center

    Grondin, S.; Girard, C.

    2005-01-01

    The purpose of the present study was to identify differences between cerebral hemispheres for processing temporal intervals ranging from .9 to 1.4s. The intervals to be judged were marked by series of brief visual signals located in the left or the right visual field. Series of three (two standards and one comparison) or five intervals (four…

  13. A METHOD OF DETERMINING A CONFIDENCE INTERVAL FOR AVAILABILITY

    DTIC Science & Technology

    This report presents a method of determining a confidence interval for availability when it is estimated from the mean time between equipment...for a confidence interval for availability. An example is included to demonstrate the procedure of placing a confidence interval about the estimated availability.

  14. Prehospital Emergency Medical Services Departure Interval: Does Patient Age Matter?

    PubMed

    Schnegg, Bruno; Pasquier, Mathieu; Carron, Pierre-Nicolas; Yersin, Bertrand; Dami, Fabrice

    2016-12-01

    Introduction The concept of response time with minimal interval is intimately related to the practice of emergency medicine. The factors influencing this time interval are poorly understood. Problem In a process of improvement of response time, the impact of the patient's age on ambulance departure intervals was investigated.

  15. Central Difference Interval Method for Solving the Wave Equation

    SciTech Connect

    Szyszka, Barbara

    2010-09-30

    This paper presents path of construction the interval method of second order for solving the wave equation. Taken into consideration is the central difference interval method for one-dimensional partial differential equation. Numerical results, obtained by two presented algorithms, in floating-point interval arithmetic are considered.

  16. Application of Sequential Interval Estimation to Adaptive Mastery Testing

    ERIC Educational Resources Information Center

    Chang, Yuan-chin Ivan

    2005-01-01

    In this paper, we apply sequential one-sided confidence interval estimation procedures with beta-protection to adaptive mastery testing. The procedures of fixed-width and fixed proportional accuracy confidence interval estimation can be viewed as extensions of one-sided confidence interval procedures. It can be shown that the adaptive mastery…

  17. Dissimilar Physiological and Perceptual Responses Between Sprint Interval Training and High-Intensity Interval Training.

    PubMed

    Wood, Kimberly M; Olive, Brittany; LaValle, Kaylyn; Thompson, Heather; Greer, Kevin; Astorino, Todd A

    2016-01-01

    High-intensity interval training (HIIT) and sprint interval training (SIT) elicit similar cardiovascular and metabolic adaptations vs. endurance training. No study, however, has investigated acute physiological changes during HIIT vs. SIT. This study compared acute changes in heart rate (HR), blood lactate concentration (BLa), oxygen uptake (VO2), affect, and rating of perceived exertion (RPE) during HIIT and SIT. Active adults (4 women and 8 men, age = 24.2 ± 6.2 years) initially performed a VO2max test to determine workload for both sessions on the cycle ergometer, whose order was randomized. Sprint interval training consisted of 8 bouts of 30 seconds of all-out cycling at 130% of maximum Watts (Wmax). High-intensity interval training consisted of eight 60-second bouts at 85% Wmax. Heart rate, VO2, BLa, affect, and RPE were continuously assessed throughout exercise. Repeated-measures analysis of variance revealed a significant difference between HIIT and SIT for VO2 (p < 0.001), HR (p < 0.001), RPE (p = 0.03), and BLa (p = 0.049). Conversely, there was no significant difference between regimens for affect (p = 0.12). Energy expenditure was significantly higher (p = 0.02) in HIIT (209.3 ± 40.3 kcal) vs. SIT (193.5 ± 39.6 kcal). During HIIT, subjects burned significantly more calories and reported lower perceived exertion than SIT. The higher VO2 and lower BLa in HIIT vs. SIT reflected dissimilar metabolic perturbation between regimens, which may elicit unique long-term adaptations. If an individual is seeking to burn slightly more calories, maintain a higher oxygen uptake, and perceive less exertion during exercise, HIIT is the recommended routine.

  18. RR-Interval variance of electrocardiogram for atrial fibrillation detection

    NASA Astrophysics Data System (ADS)

    Nuryani, N.; Solikhah, M.; Nugoho, A. S.; Afdala, A.; Anzihory, E.

    2016-11-01

    Atrial fibrillation is a serious heart problem originated from the upper chamber of the heart. The common indication of atrial fibrillation is irregularity of R peak-to-R-peak time interval, which is shortly called RR interval. The irregularity could be represented using variance or spread of RR interval. This article presents a system to detect atrial fibrillation using variances. Using clinical data of patients with atrial fibrillation attack, it is shown that the variance of electrocardiographic RR interval are higher during atrial fibrillation, compared to the normal one. Utilizing a simple detection technique and variances of RR intervals, we find a good performance of atrial fibrillation detection.

  19. Volatility return intervals analysis of the Japanese market

    NASA Astrophysics Data System (ADS)

    Jung, W.-S.; Wang, F. Z.; Havlin, S.; Kaizoji, T.; Moon, H.-T.; Stanley, H. E.

    2008-03-01

    We investigate scaling and memory effects in return intervals between price volatilities above a certain threshold q for the Japanese stock market using daily and intraday data sets. We find that the distribution of return intervals can be approximated by a scaling function that depends only on the ratio between the return interval τ and its mean <τ>. We also find memory effects such that a large (or small) return interval follows a large (or small) interval by investigating the conditional distribution and mean return interval. The results are similar to previous studies of other markets and indicate that similar statistical features appear in different financial markets. We also compare our results between the period before and after the big crash at the end of 1989. We find that scaling and memory effects of the return intervals show similar features although the statistical properties of the returns are different.

  20. Organic-inorganic hybrid materials starting from the novel nanoscaled bismuth oxido methacrylate cluster [Bi38O45(OMc)24(DMSO)9]·2DMSO·7H2O.

    PubMed

    Miersch, Linda; Rüffer, Tobias; Mehring, Michael

    2011-06-14

    The reaction of the basic bismuth nitrate [Bi(6)O(4)(OH)(4)](NO(3))(6)·H(2)O with sodium methacrylate in DMSO gave [Bi(38)O(45)(OMc)(24)(DMSO)(9)]·2DMSO·7H(2)O (OMc = O(2)CC(3)H(5)), which is highly soluble in organic solvents. By copolymerization of the bismuth oxido cluster with methyl methacrylate transparent, radiopaque organic-inorganic hybrid materials were obtained. This journal is © The Royal Society of Chemistry 2011

  1. Nqrs Data for C9H26N3Na2O14P [C9H12N3Na2O7P·7(H2O)] (Subst. No. 1198)

    NASA Astrophysics Data System (ADS)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume A `Substances Containing Ag … C10H15' of Volume 48 `Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III `Condensed Matter'. It contains an extract of Section `3.2 Data tables' of the Chapter `3 Nuclear quadrupole resonance data' providing the NQRS data for C9H26N3Na2O14P [C9H12N3Na2O7P·7(H2O)] (Subst. No. 1198)

  2. Heat of Mixing and Solution of Heptane C7H16 + C8H20N2 N,N,N',N'-Tetramethylbutane-1,4-diamine (HMSD1111, LB3850_H)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume B 'Binary Liquid Systems of Nonelectrolytes II' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Heat of Mixing and Solution of Heptane C7H16 + C8H20N2 N,N,N',N'-Tetramethylbutane-1,4-diamine (HMSD1111, LB3850_H)' providing data from direct low-pressure calorimetric measurement of molar excess enthalpy at variable mole fraction and constant temperature.

  3. Safety and Biodistribution Evaluation in CNGB3-Deficient Mice of rAAV2tYF-PR1.7-hCNGB3, a Recombinant AAV Vector for Treatment of Achromatopsia.

    PubMed

    Ye, Guo-jie; Budzynski, Ewa; Sonnentag, Peter; Nork, T Michael; Miller, Paul E; McPherson, Leslie; Ver Hoeve, James N; Smith, Leia M; Arndt, Tara; Mandapati, Savitri; Robinson, Paulette M; Calcedo, Roberto; Knop, David R; Hauswirth, William W; Chulay, Jeffrey D

    2016-03-01

    Applied Genetic Technologies Corporation (AGTC) is developing rAAV2tYF-PR1.7-hCNGB3, a recombinant adeno-associated virus (rAAV) vector expressing the human CNGB3 gene, for treatment of achromatopsia, an inherited retinal disorder characterized by markedly reduced visual acuity, extreme light sensitivity, and absence of color discrimination. We report here results of a study evaluating safety and biodistribution of rAAV2tYF-PR1.7-hCNGB3 in CNGB3-deficient mice. Three groups of animals (n = 35 males and 35 females per group) received a subretinal injection in one eye of 1 μl containing either vehicle or rAAV2tYF-PR1.7-hCNGB3 at one of two dose concentrations (1 × 10(12) or 4.2 × 10(12) vg/ml) and were euthanized 4 or 13 weeks later. There were no test-article-related changes in clinical observations, body weights, food consumption, ocular examinations, clinical pathology parameters, organ weights, or macroscopic observations at necropsy. Cone-mediated electroretinography (ERG) responses were detected after vector administration in the treated eyes in 90% of animals in the higher dose group and 31% of animals in the lower dose group. Rod-mediated ERG responses were reduced in the treated eye for all groups, with the greatest reduction in males given the higher dose of vector, but returned to normal by the end of the study. Microscopic pathology results demonstrated minimal mononuclear cell infiltrates in the retina and vitreous of some animals at the interim euthanasia and in the vitreous of some animals at the terminal euthanasia. Serum anti-AAV antibodies developed in most vector-injected animals. No animals developed antibodies to hCNGB3. Biodistribution studies demonstrated high levels of vector DNA in vector-injected eyes but little or no vector DNA in nonocular tissue. These results support the use of rAAV2tYF-PR1.7-hCNGB3 in clinical studies in patients with achromatopsia caused by CNGB3 mutations.

  4. Determination of the anti-tumor agent, 10-chloro-5-(2-dimethylaminoethyl)-7h-indolo[2,3-c] quinoline-6(5h)-one. HCl in blood or plasma by high-performance liquid chromatography.

    PubMed

    Strojny, N; D'Arconte, L; de Silva, J A

    1981-04-10

    A sensitive and specific high-performance liquid chromatographic assay was developed for the determination of 10-chloro-5-(2-dimethylaminoethyl)-7H-indolo [2,3-C] quinolin-6(5H) one [I] in blood or plasma with an overall recovery of 100.3 +/- 9.1% and a limit of quantitation of 1.0 ng per ml of blood or plasma. the assay was used to determine blood concentrations of the drug in the rat following oral administration by intubation of a 1.17-mg dose of [I] . HCl.

  5. Differences in Physiological Responses to Interval Training in Cyclists With and Without Interval Training Experience

    PubMed Central

    Hebisz, Rafal; Borkowski, Jacek; Zatoń, Marek

    2016-01-01

    Abstract The aim of this study was to determine differences in glycolytic metabolite concentrations and work output in response to an all-out interval training session in 23 cyclists with at least 2 years of interval training experience (E) and those inexperienced (IE) in this form of training. The intervention involved subsequent sets of maximal intensity exercise on a cycle ergometer. Each set comprised four 30 s repetitions interspersed with 90 s recovery periods; sets were repeated when blood pH returned to 7.3. Measurements of post-exercise hydrogen (H+) and lactate ion (LA-) concentrations and work output were taken. The experienced cyclists performed significantly more sets of maximal efforts than the inexperienced athletes (5.8 ± 1.2 vs. 4.3 ± 0.9 sets, respectively). Work output decreased in each subsequent set in the IE group and only in the last set in the E group. Distribution of power output changed only in the E group; power decreased in the initial repetitions of set only to increase in the final repetitions. H+ concentration decreased in the third, penultimate, and last sets in the E group and in each subsequent set in the IE group. LA- decreased in the last set in both groups. In conclusion, the experienced cyclists were able to repeatedly induce elevated levels of lactic acidosis. Power output distribution changed with decreased acid–base imbalance. In this way, this group could compensate for a decreased anaerobic metabolism. The above factors allowed cyclists experienced in interval training to perform more sets of maximal exercise without a decrease in power output compared with inexperienced cyclists. PMID:28149346

  6. Differences in Physiological Responses to Interval Training in Cyclists With and Without Interval Training Experience.

    PubMed

    Hebisz, Rafal; Hebisz, Paulina; Borkowski, Jacek; Zatoń, Marek

    2016-04-01

    The aim of this study was to determine differences in glycolytic metabolite concentrations and work output in response to an all-out interval training session in 23 cyclists with at least 2 years of interval training experience (E) and those inexperienced (IE) in this form of training. The intervention involved subsequent sets of maximal intensity exercise on a cycle ergometer. Each set comprised four 30 s repetitions interspersed with 90 s recovery periods; sets were repeated when blood pH returned to 7.3. Measurements of post-exercise hydrogen (H+) and lactate ion (LA-) concentrations and work output were taken. The experienced cyclists performed significantly more sets of maximal efforts than the inexperienced athletes (5.8 ± 1.2 vs. 4.3 ± 0.9 sets, respectively). Work output decreased in each subsequent set in the IE group and only in the last set in the E group. Distribution of power output changed only in the E group; power decreased in the initial repetitions of set only to increase in the final repetitions. H+ concentration decreased in the third, penultimate, and last sets in the E group and in each subsequent set in the IE group. LA- decreased in the last set in both groups. In conclusion, the experienced cyclists were able to repeatedly induce elevated levels of lactic acidosis. Power output distribution changed with decreased acid-base imbalance. In this way, this group could compensate for a decreased anaerobic metabolism. The above factors allowed cyclists experienced in interval training to perform more sets of maximal exercise without a decrease in power output compared with inexperienced cyclists.

  7. Investigating TMS-EEG Indices of Long-Interval Intracortical Inhibition at Different Interstimulus Intervals.

    PubMed

    Opie, George M; Rogasch, Nigel C; Goldsworthy, Mitchell R; Ridding, Michael C; Semmler, John G

    Long-interval intracortical inhibition (LICI) is a transcranial magnetic stimulation (TMS) paradigm that uses paired magnetic stimuli separated by 100-200 ms to investigate the activity of cortical GABAergic interneurons. While commonly applied, the mechanisms contributing to LICI are not well understood, and growing evidence suggests that inhibition observed at different interstimulus intervals (ISI) may involve non-identical processes. This study aims to utilise combined TMS-EEG to more thoroughly characterise LICI at different ISIs, as the TMS-evoked EEG potential (TEP) can provide more direct insight into the cortical response to stimulation that is not subject to variations in spinal cord excitability that can confound the motor evoked potential (MEP). In 12 subjects (22.6 ± 0.9 years), LICI was applied using two ISIs of 100 ms (LICI100) and 150 ms (LICI150), while TEPs were recorded using simultaneous high-definition EEG. Analysis of EEG data within a region of interest (C3 electrode) showed that test alone stimulation produced three consistent TEP peaks (corresponding to P30, N100 and P180) that were all significantly inhibited following paired-pulse stimulation. However, for P30, inhibition varied between LICI conditions, with reduced amplitude following LICI100 (P = 0.03) but not LICI150 (P = 0.3). In contrast, the N100 and P180 were significantly reduced by LICI at both intervals (all P-values < 0.05). In addition, topographical analyses suggested that the global change in P30, N40 and P180 differed between LICI conditions. These findings suggest that LICI100 and LICI150 reflect complex measurements of cortical inhibition with differential contributions from comparable circuits. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Tuning for temporal interval in human apparent motion detection.

    PubMed

    Bours, Roger J E; Stuur, Sanne; Lankheet, Martin J M

    2007-01-08

    Detection of apparent motion in random dot patterns requires correlation across time and space. It has been difficult to study the temporal requirements for the correlation step because motion detection also depends on temporal filtering preceding correlation and on integration at the next levels. To specifically study tuning for temporal interval in the correlation step, we performed an experiment in which prefiltering and postintegration were held constant and in which we used a motion stimulus containing coherent motion for a single interval value only. The stimulus consisted of a sparse random dot pattern in which each dot was presented in two frames only, separated by a specified interval. On each frame, half of the dots were refreshed and the other half was a displaced reincarnation of the pattern generated one or several frames earlier. Motion energy statistics in such a stimulus do not vary from frame to frame, and the directional bias in spatiotemporal correlations is similar for different interval settings. We measured coherence thresholds for left-right direction discrimination by varying motion coherence levels in a Quest staircase procedure, as a function of both step size and interval. Results show that highest sensitivity was found for an interval of 17-42 ms, irrespective of viewing distance. The falloff at longer intervals was much sharper than previously described. Tuning for temporal interval was largely, but not completely, independent of step size. The optimal temporal interval slightly decreased with increasing step size. Similarly, the optimal step size decreased with increasing temporal interval.

  9. Alternative Confidence Interval Methods Used in the Diagnostic Accuracy Studies.

    PubMed

    Erdoğan, Semra; Gülhan, Orekıcı Temel

    2016-01-01

    Background/Aim. It is necessary to decide whether the newly improved methods are better than the standard or reference test or not. To decide whether the new diagnostics test is better than the gold standard test/imperfect standard test, the differences of estimated sensitivity/specificity are calculated with the help of information obtained from samples. However, to generalize this value to the population, it should be given with the confidence intervals. The aim of this study is to evaluate the confidence interval methods developed for the differences between the two dependent sensitivity/specificity values on a clinical application. Materials and Methods. In this study, confidence interval methods like Asymptotic Intervals, Conditional Intervals, Unconditional Interval, Score Intervals, and Nonparametric Methods Based on Relative Effects Intervals are used. Besides, as clinical application, data used in diagnostics study by Dickel et al. (2010) has been taken as a sample. Results. The results belonging to the alternative confidence interval methods for Nickel Sulfate, Potassium Dichromate, and Lanolin Alcohol are given as a table. Conclusion. While preferring the confidence interval methods, the researchers have to consider whether the case to be compared is single ratio or dependent binary ratio differences, the correlation coefficient between the rates in two dependent ratios and the sample sizes.

  10. The factors influence compatibility of pulse-pulse intervals with R-R intervals.

    PubMed

    Liu, An-Bang; Wu, Hsien-Tsai; Liu, Cyuan-Cin; Hsu, Chun-Hsiang; Chen, Ding-Yuan

    2013-01-01

    Cardiac autonomic dysfunction assessed by power spectral analysis of electrocardigographic (ECG) R-R intervals (RRI) is a useful method in clinical research. The compatibility of pulse-pulse intervals (PPI) acquired by photoplethysmography (PPG) with RRI is equivocal. In this study, we would like to investigate factors influence the compatibility. We recruited 25 young and health subjects divided into two groups: normal subjects (Group1, BMI < 24, n=15) and overweight subjects (Group2, BMI >/= 24, n=10). ECG and PPG were measured for 5 minutes. Used cross-approximate entropy (CAE) and Fast Fourier transform (FFT) to obtained compatibility between RRI and PPI. The CAE value in Group1 were significantly lower than in Group2 (1.71 ± 0.12 vs. 1.83 ± 0.11, P = 0.011). A positive linear relationship between CAE value and risk factors of metabolic syndrome. No significantly difference between LFP/HFP ratio of RRI (LHRRRI) and LFP/HFP ratio of PPI (LHRPPI) in Group1 (1.42 ± 0.19 vs. 1.38 ± 0.17, P = 0.064), LHRRRI significantly higher than LHRPPI in Group2 (2.18 ± 0.37 vs. 1.93 ± 0.30, P = 0.005). It should be careful that using PPI to assess autonomic function in the obese subjects or the patients with metabolic syndrome.

  11. Interval timing in Siamese fighting fish (Betta splendens).

    PubMed

    Higa, J J; Simm, L A

    2004-11-30

    The present study evaluated the temporal performance of Siamese fighting fish (Betta splendens) given short-term exposure to four fixed interval (FI) schedules of reinforcement, FI 30, 60, 120, and 240 s, during which a reinforcer (mirror image) was given for the first response (swimming through a hoop) after the interval requirement had elapsed. Response levels were generally low early in an interval and increased as the interval elapsed; wait times and break points in an interval increased with increases in the FI requirement. The results were similar to that obtained with other species and different types of responses and reinforcers, and demonstrate that the procedure is a feasible method for studying interval timing in fish.

  12. Reference intervals data mining: no longer a probability paper method.

    PubMed

    Katayev, Alexander; Fleming, James K; Luo, Dajie; Fisher, Arren H; Sharp, Thomas M

    2015-01-01

    To describe the application of a data-mining statistical algorithm for calculation of clinical laboratory tests reference intervals. Reference intervals for eight different analytes and different age and sex groups (a total of 11 separate reference intervals) for tests that are unlikely to be ordered during routine screening of disease-free populations were calculated using the modified algorithm for data mining of test results stored in the laboratory database and compared with published peer-reviewed studies that used direct sampling. The selection of analytes was based on the predefined criteria that include comparability of analytical methods with a statistically significant number of observations. Of the 11 calculated reference intervals, having upper and lower limits for each, 21 of 22 reference interval limits were not statistically different from the reference studies. The presented statistical algorithm is shown to be an accurate and practical tool for reference interval calculations. Copyright© by the American Society for Clinical Pathology.

  13. Extended flowering intervals of bamboos evolved by discrete multiplication.

    PubMed

    Veller, Carl; Nowak, Martin A; Davis, Charles C

    2015-07-01

    Numerous bamboo species collectively flower and seed at dramatically extended, regular intervals - some as long as 120 years. These collective seed releases, termed 'masts', are thought to be a strategy to overwhelm seed predators or to maximise pollination rates. But why are the intervals so long, and how did they evolve? We propose a simple mathematical model that supports their evolution as a two-step process: First, an initial phase in which a mostly annually flowering population synchronises onto a small multi-year interval. Second, a phase of successive small multiplications of the initial synchronisation interval, resulting in the extraordinary intervals seen today. A prediction of the hypothesis is that mast intervals observed today should factorise into small prime numbers. Using a historical data set of bamboo flowering observations, we find strong evidence in favour of this prediction. Our hypothesis provides the first theoretical explanation for the mechanism underlying this remarkable phenomenon. © 2015 John Wiley & Sons Ltd/CNRS.

  14. Contrasting Diversity Values: Statistical Inferences Based on Overlapping Confidence Intervals

    PubMed Central

    MacGregor-Fors, Ian; Payton, Mark E.

    2013-01-01

    Ecologists often contrast diversity (species richness and abundances) using tests for comparing means or indices. However, many popular software applications do not support performing standard inferential statistics for estimates of species richness and/or density. In this study we simulated the behavior of asymmetric log-normal confidence intervals and determined an interval level that mimics statistical tests with P(α) = 0.05 when confidence intervals from two distributions do not overlap. Our results show that 84% confidence intervals robustly mimic 0.05 statistical tests for asymmetric confidence intervals, as has been demonstrated for symmetric ones in the past. Finally, we provide detailed user-guides for calculating 84% confidence intervals in two of the most robust and highly-used freeware related to diversity measurements for wildlife (i.e., EstimateS, Distance). PMID:23437239

  15. Contrasting diversity values: statistical inferences based on overlapping confidence intervals.

    PubMed

    MacGregor-Fors, Ian; Payton, Mark E

    2013-01-01

    Ecologists often contrast diversity (species richness and abundances) using tests for comparing means or indices. However, many popular software applications do not support performing standard inferential statistics for estimates of species richness and/or density. In this study we simulated the behavior of asymmetric log-normal confidence intervals and determined an interval level that mimics statistical tests with P(α) = 0.05 when confidence intervals from two distributions do not overlap. Our results show that 84% confidence intervals robustly mimic 0.05 statistical tests for asymmetric confidence intervals, as has been demonstrated for symmetric ones in the past. Finally, we provide detailed user-guides for calculating 84% confidence intervals in two of the most robust and highly-used freeware related to diversity measurements for wildlife (i.e., EstimateS, Distance).

  16. Recommended confidence intervals for two independent binomial proportions.

    PubMed

    Fagerland, Morten W; Lydersen, Stian; Laake, Petter

    2015-04-01

    The relationship between two independent binomial proportions is commonly estimated and presented using the difference between proportions, the number needed to treat, the ratio of proportions or the odds ratio. Several different confidence intervals are available, but they can produce markedly different results. Some of the traditional approaches, such as the Wald interval for the difference between proportions and the Katz log interval for the ratio of proportions, do not perform well unless the sample size is large. Better intervals are available. This article describes and compares approximate and exact confidence intervals that are - with one exception - easy to calculate or available in common software packages. We illustrate the performances of the intervals and make recommendations for both small and moderate-to-large sample sizes. © The Author(s) 2011 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  17. IBM system/360 assembly language interval arithmetic software

    NASA Technical Reports Server (NTRS)

    Phillips, E. J.

    1972-01-01

    Computer software designed to perform interval arithmetic is described. An interval is defined as the set of all real numbers between two given numbers including or excluding one or both endpoints. Interval arithmetic consists of the various elementary arithmetic operations defined on the set of all intervals, such as interval addition, subtraction, union, etc. One of the main applications of interval arithmetic is in the area of error analysis of computer calculations. For example, it has been used sucessfully to compute bounds on sounding errors in the solution of linear algebraic systems, error bounds in numerical solutions of ordinary differential equations, as well as integral equations and boundary value problems. The described software enables users to implement algorithms of the type described in references efficiently on the IBM 360 system.

  18. The different effects of high intensity interval training and moderate intensity interval training for weightlessness countermeasures

    NASA Astrophysics Data System (ADS)

    Wang, Lin-Jie; Cheng, Tan; Zhi-Li, Li; Hui-juan, Wang; Wen-juan, Chen; Jianfeng, Zhang; Desheng, Wang; Dongbin, Niu; Qi, Zhao; Chengjia, Yang; Yanqing, Wang

    High intensity interval training (HIIT) has been demonstrated to improve performance in a relatively short training period. But the difference between high intensity interval training and moderate intensity interval training (MIIT) in simulated weightlessness still has not been well studied. This study sought to characterize the difference between 6 weeks high intensity interval training and moderate intensity interval training under reduced weight (RW) gait training device and zero-gravity locomotion system (ZLS). Twenty-three subjects (14M/4F, 32.5±4.5 years) volunteered to participate. They were divided into three groups, that were MITT (alternating 2 min at 40% VO _{2} peak and 2 min at 60% VO _{2} peak for 30min, five days per week) RW group (n=8), HITT (alternating 2 min at 40% VO _{2} peak and 2 min at 90% VO _{2} peak for 30min, three days per week) RW group (n=8) and HITT ZLS group (n=7). The Z-axis load used in RW group was 80% body weight (BW) and in ZLS was 100% BW. Cardiopulmonary function was measured before, after 4-week training and after 6-week training. Isokinetic knee extension-flexion test at 60(°) deg/s and 180(°) deg/s were performed before and after the 6-week training, and isometric knee extension-flexion test at 180(°) deg/s was also examined at the same time. It was found that the VO _{2} peaks, metabolic equivalent (MET), Speedmax and respiratory exchange ratio (RER) were significantly increased after 4 and 6-week training in all three groups and no significant group difference were detected. The peak torque at 60(°) deg/s for right knee flexion were significantly increased after 6 week-training in all three groups, and only in HITT RW group the total power at 60(°) deg/s for right knee flexion enhanced. The total power and average power at 60(°) deg/s for right knee extension decreased significantly after 6-week training in all three groups. The peak torque at 60(°) deg/s for right knee extension in MIIT RW group was

  19. Synthesis, characterization, electrochemical investigation and antioxidant activities of a new hybrid cyclohexaphosphate: Cu1.5Li(C2H10N2)P6O18·7H2O

    NASA Astrophysics Data System (ADS)

    Sleymi, Samira; Lahbib, Karima; Rahmouni, Nihed; Rzaigui, Mohamed; Besbes-Hentati, Salma; Abid, Sonia

    2017-09-01

    A new organic-inorganic hybrid transition metal phosphate, Cu1.5Li(C2H10N2)P6O18·7H2O, has been prepared and characterized by X-ray diffraction, spectroscopy (infrared, Raman, diffuse reflectance and UV-Vis) and thermal analysis (TG). In addition, its electrochemical behaviors, as well as its antioxidant and antibacterial activities, have been investigated. Its structure is built up by the alternate linkages between copper and phosphate polyhedra, forming puckered layers with intersecting 12-membered rings, in which the ethylenediammonium cations reside. This compound is the first framework structure constructed from cyclohexaphosphates and three distinct copper cations. Cyclic voltammetry study in an acetonitrile solution reveals the facile anodic oxidation of its organic part on a platinum disk and a progressive growing of a thin film, though the repetitive cycling of potential. The title compound was tested for its in vitro antioxidant activities by 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2‧-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), Ferrous chelating ability (FIC) and Ferric Reducing Power (FRP) methods. The antioxidant activity of Cu1.5Li(C2H10N2)P6O18·7H2O was analyzed simultaneously with its antibacterial capacity against Escherichia coli, Salmonella typhimurium, Staphylococus aureus, Enterococcus feacium, Streptococcus agalactiae and Candida albicans. The tested compound showed significant antioxidant activities with low antibacterial properties.

  20. Ab initio/GIAO-CCSD(T) (13)C NMR study of the rearrangement and dynamic aspects of rapidly equilibrating tertiary carbocations, C6H13(+) and C7H15(+).

    PubMed

    Olah, George A; Prakash, G K Surya; Rasul, Golam

    2016-01-05

    The rearrangement pathways of the equilibrating tertiary carbocations, 2,3-dimethyl-2-butyl cation (C6H13(+), 1), 2,3,3-trimethyl-2-butyl cation (C7H15(+), 5) and 2,3-dimethyl-2-pentyl cation (C7H15(+), 8 and 9) were investigated using the ab initio/GIAO-CCSD(T) (13)C NMR method. Comparing the calculated and experimental (13)C NMR chemical shifts of a series of carbocations indicates that excellent prediction of δ(13)C could be achieved through scaling. In the case of symmetrical equilibrating cations (1 and 5) the Wagner-Meerwein 1,2-hydride and 1,2-methide shifts, respectively, produce the same structure. This indicates that the overall (13)C NMR chemical shifts are conserved and independent of temperature. However, in the case of unsymmetrical equilibrating cations (8 and 9) the Wagner-Meerwein shift produces different tertiary structures, which have slightly different thermodynamic stabilities and, thus, different spectra. At the MP4(SDTQ)/cc-pVTZ//MP2/cc-pVTZ + ZPE level structure 8 is only 90 calories/mol more stable than structure 9. Based on computed (13)C NMR chemical shift calculations, mole fractions of these isomers were determined by assuming the observed chemical shifts are due to the weighted average of the chemical shifts of the static ions.

  1. Temperature-dependent interactions and disorder in the spin-transition compound [Fe(II)(L)2][ClO4]2.C7H8 through structural, calorimetric, magnetic, photomagnetic, and diffuse reflectance investigations.

    PubMed

    Mishra, Vibha; Mukherjee, Rabindranath; Linares, Jorge; Balde, Chérif; Desplanches, Cédric; Létard, Jean-François; Collet, Eric; Toupet, Loic; Castro, Miguel; Varret, François

    2008-09-01

    The title compound [Fe (II)(L) 2][ClO 4] 2.C 7H 8 (L = 2-[3-(2'-pyridyl)pyrazol-1-ylmethyl]pyridine) has been isolated while attempting to grow single crystals of the spin-transition (continuous-type) compound [Fe (II)(L) 2][ClO 4] 2, published earlier ( Dalton Trans. 2003, 3392-3397). Magnetic susceptibility measurements, as well as Mossbauer and calorimetric investigations on polycrystalline samples of [Fe(L) 2][ClO 4] 2.C 7H 8 revealed the occurrence of an abrupt HS ( (5) T 2) <--> LS ( (1) A 1) transition with steep and narrow (2 K) hysteresis at approximately 232 K. The photomagnetic properties exhibit features typical for a broad distribution of activation energies, with relaxation curves in the shape of stretched exponentials. We performed a crystal structure determination of the compound at 120, 240, and 270 K. A noteworthy temperature-dependent behavior of the structural parameters was observed, in terms of disorder of both the anions and solvent molecules, leading to a strong thermal dependence of the strength and dimensionality of the interaction network. Additional data were obtained by diffuse reflectance measurements. We model and discuss the antagonistic effects of interactions and disorder by using a two-level cooperative mean-field approach which includes a distribution of barrier energies at the microscopic scale.

  2. Contemporary Avian Influenza A Virus Subtype H1, H6, H7, H10, and H15 Hemagglutinin Genes Encode a Mammalian Virulence Factor Similar to the 1918 Pandemic Virus H1 Hemagglutinin

    PubMed Central

    Qi, Li; Pujanauski, Lindsey M.; Davis, A. Sally; Schwartzman, Louis M.; Chertow, Daniel S.; Baxter, David; Scherler, Kelsey; Hartshorn, Kevan L.; Slemons, Richard D.; Walters, Kathie-Anne; Kash, John C.

    2014-01-01

    ABSTRACT Zoonotic avian influenza virus infections may lead to epidemics or pandemics. The 1918 pandemic influenza virus has an avian influenza virus-like genome, and its H1 hemagglutinin was identified as a key mammalian virulence factor. A chimeric 1918 virus expressing a contemporary avian H1 hemagglutinin, however, displayed murine pathogenicity indistinguishable from that of the 1918 virus. Here, isogenic chimeric avian influenza viruses were constructed on an avian influenza virus backbone, differing only by hemagglutinin subtype expressed. Viruses expressing the avian H1, H6, H7, H10, and H15 subtypes were pathogenic in mice and cytopathic in normal human bronchial epithelial cells, in contrast to H2-, H3-, H5-, H9-, H11-, H13-, H14-, and H16-expressing viruses. Mouse pathogenicity was associated with pulmonary macrophage and neutrophil recruitment. These data suggest that avian influenza virus hemagglutinins H1, H6, H7, H10, and H15 contain inherent mammalian virulence factors and likely share a key virulence property of the 1918 virus. Consequently, zoonotic infections with avian influenza viruses bearing one of these hemagglutinins may cause enhanced disease in mammals. PMID:25406382

  3. Supra-molecular architecture in a co-crystal of the N(7)-H tautomeric form of N (6)-benzoyl-adenine with adipic acid (1/0.5).

    PubMed

    Swinton Darious, Robert; Thomas Muthiah, Packianathan; Perdih, Franc

    2016-06-01

    The asymmetric unit of the title co-crystal, C12H9N5O·0.5C6H10O4, consists of one mol-ecule of N (6)-benzoyl-adenine (BA) and one half-mol-ecule of adipic acid (AA), the other half being generated by inversion symmetry. The dihedral angle between the adenine and phenyl ring planes is 26.71 (7)°. The N (6)-benzoyl-adenine mol-ecule crystallizes in the N(7)-H tautomeric form with three non-protonated N atoms. This tautomeric form is stabilized by intra-molecular N-H⋯O hydrogen bonding between the carbonyl (C=O) group and the N(7)-H hydrogen atom on the Hoogsteen face of the purine ring, forming an S(7) ring motif. The two carboxyl groups of adipic acid inter-act with the Watson-Crick face of the BA mol-ecules through O-H⋯N and N-H⋯O hydrogen bonds, generating an R 2 (2)(8) ring motif. The latter units are linked by N-H⋯N hydrogen bonds, forming layers parallel to (10-5). A weak C-H⋯O hydrogen bond is also present, linking adipic acid mol-ecules in neighbouring layers, enclosing R (2) 2(10) ring motifs and forming a three-dimensional structure. C=O⋯π and C-H⋯π inter-actions are also present in the structure.

  4. Structural Characterization and Antimicrobial Activities of 7H-Benzo[h]chromeno[2,3-d]pyrimidine and 14H-Benzo[h]chromeno[3,2-e][1,2,4]triazolo[1,5-c] pyrimidine Derivatives.

    PubMed

    Okasha, Rawda M; Albalawi, Fawzia F; Afifi, Tarek H; Fouda, Ahmed M; Al-Dies, Al-Anood M; El-Agrody, Ahmed M

    2016-11-01

    Three new series of chromene molecules have been synthesized in order to explore their antimicrobial activity. The series encompass 2-substituted 14-(4-halophenyl)-12-methoxy-14H-benzo[h]chromeno[3,2-e][1,2,4]-triazolo[1,5-c]pyrimidines 7a-o, 9-benzylideneamino-7-(4-halo-phenyl)-5-methoxy-8-imino-7H-benzo-[h]chromeno[2,3-d]pyrimidines 8a-b and 3-ethoxycarbonyl-14-(4-halophenyl)-12-methoxy-14H-benzo-[h]chromeno[3,2-e][1,2,4]triazolo[1,5-c]pyrimidine-2-one derivatives 12a-b. The structure of these novel compounds were confirmed using IR, ¹H- and (13)C-NMR as well as MS spectroscopy. The new compounds were evaluated in vitro for their antimicrobial activity and it was demonstrated that 7H-benzochromenopyrimidine and derivatives of 14H-benzochromenotriazolopyrimidine exhibited the most promising antibacterial activities compared to the reference antimicrobial agents. The structure activity relationship (SAR) studies of the target compounds agreed with the in vitro essays and confirmed higher potent antimicrobial activity against some of the tested microorganisms.

  5. Simultaneous Confidence Intervals Based on the Percentile Bootstrap Approach

    PubMed Central

    Mandel, Micha; Betensky, Rebecca A.

    2007-01-01

    This note concerns the construction of bootstrap simultaneous confidence intervals (SCI) for m parameters. Given B bootstrap samples, we suggest an algorithm with complexity of O(mB log(B)). We apply our algorithm to construct a confidence region for time dependent probabilities of progression in multiple sclerosis and for coefficients in a logistic regression analysis. Alternative normal based simultaneous confidence intervals are presented and compared to the bootstrap intervals. PMID:19137059

  6. Confidence Interval Methodology for Ratio Means (CIM4RM)

    DTIC Science & Technology

    2010-08-01

    RDECOIW 40 Years of SAA Excellence in Analysis AMSAA TECHNICAL REPORT NO. TR-2010-35 CONFIDENCE INTERVAL METHODOLOGY FOR RATIO MEANS (CIM4RM...COVERED Technical Report 4 TITLE AND SUBTITLE Confidence Interval Methodology for Ratio Means (CIM4RM) 5 FUNDING NUMBERS 6 AUTHOR!SI John Nierwinski...LIST OF ACRONYMS CIM4RM - Confidence Interval Methodology for Ratio Means MH - Man-Hours MR - Maintenance Ratio PCM - Parts Cost per Mile CI

  7. Pregbalin induced recurrent syncopal attacks with prolong QT interval.

    PubMed

    Adar, Adem; Cakan, Fahri; Önalan, Orhan

    2017-08-30

    Long QT syndrome may lead to fatal dysrhythmia. Prolongation of QT interval due to pregabalin has been shown in rats and no data is available in humans. We report a 80-year-old female patient using pregabalin. She was presented to emergency room with syncope attacks. Her admission electrocardiography demonstrated prolonged QT interval. After excluding the possible causes of the long QT syndrome, we attributed prolonged QT interval to pregabalin therapy. After discontinuation of pregabalin QT interval returned to normal range and patient experienced no further syncope attacks. It is first time for documentation of prolonged QT due to pregabalin in humans. © 2017 Wiley Periodicals, Inc.

  8. Hydrologic studies in wells open through large intervals

    SciTech Connect

    Not Available

    1992-01-01

    This report describes and summarizes activities, data, and preliminary data interpretation from the INEL Oversight Program R D-1 project titled Hydrologic Studies In Wells Open Through Large Intervals.'' The project is designed to use a straddle-packer system to isolate, hydraulically test, and sample specific intervals of monitoring wells that are open (uncased, unscreened) over large intervals of the Snake River Plain aquifer. The objectives of the project are to determine and compare vertical variations in water quality and aquifer properties that have previously only been determined in an integrated fashion over the entire thickness of the open interval of the observation wells.

  9. Clinical and Biological Features of Interval Colorectal Cancer

    PubMed Central

    Lee, Yu Mi; Huh, Kyu Chan

    2017-01-01

    Interval colorectal cancer (I-CRC) is defined as a CRC diagnosed within 60 months after a negative colonoscopy, taking into account that 5 years is the “mean sojourn time.” It is important to prevent the development of interval cancer. The development of interval colon cancer is associated with female sex, old age, family history of CRC, comorbidities, diverticulosis, and the skill of the endoscopist. During carcinogenesis, sessile serrated adenomas/polyps (SSA/Ps) share many genomic and colonic site characteristics with I-CRCs. The clinical and biological features of I-CRC should be elucidated to prevent the development of interval colon cancer. PMID:28320200

  10. Intertrial interval duration and learning in autistic children.

    PubMed

    Koegel, R L; Dunlap, G; Dyer, K

    1980-01-01

    This study investigated the influence of intertrial interval duration on the performance of autistic children during teaching situations. The children were taught under the same conditions existing in their regular programs, except that the length of time between trials was systematically manipulated. With both multiple baseline and repeated reversal designs, two lengths of intertrial interval were employed; short intervals with the SD for any given trial presented approximately one second following the reinforcer for the previous trial versus long intervals with the SD presented four or more seconds following the reinforcer for the previous trial. The results showed that: (1) the short intertrial intervals always produced higher levels of correct responding than the long intervals; and (2) there were improving trends in performance and rapid acquisition with the short intertrial intervals, in contrast to minimal or no change with the long intervals. The results are discussed in terms of utilizing information about child and task characteristics in terms of selecting optimal intervals. The data suggest that manipulations made between trials have a large influence on autistic children's learning.

  11. Comparing interval estimates for small sample ordinal CFA models.

    PubMed

    Natesan, Prathiba

    2015-01-01

    Robust maximum likelihood (RML) and asymptotically generalized least squares (AGLS) methods have been recommended for fitting ordinal structural equation models. Studies show that some of these methods underestimate standard errors. However, these studies have not investigated the coverage and bias of interval estimates. An estimate with a reasonable standard error could still be severely biased. This can only be known by systematically investigating the interval estimates. The present study compares Bayesian, RML, and AGLS interval estimates of factor correlations in ordinal confirmatory factor analysis models (CFA) for small sample data. Six sample sizes, 3 factor correlations, and 2 factor score distributions (multivariate normal and multivariate mildly skewed) were studied. Two Bayesian prior specifications, informative and relatively less informative were studied. Undercoverage of confidence intervals and underestimation of standard errors was common in non-Bayesian methods. Underestimated standard errors may lead to inflated Type-I error rates. Non-Bayesian intervals were more positive biased than negatively biased, that is, most intervals that did not contain the true value were greater than the true value. Some non-Bayesian methods had non-converging and inadmissible solutions for small samples and non-normal data. Bayesian empirical standard error estimates for informative and relatively less informative priors were closer to the average standard errors of the estimates. The coverage of Bayesian credibility intervals was closer to what was expected with overcoverage in a few cases. Although some Bayesian credibility intervals were wider, they reflected the nature of statistical uncertainty that comes with the data (e.g., small sample). Bayesian point estimates were also more accurate than non-Bayesian estimates. The results illustrate the importance of analyzing coverage and bias of interval estimates, and how ignoring interval estimates can be misleading

  12. Comparing interval estimates for small sample ordinal CFA models

    PubMed Central

    Natesan, Prathiba

    2015-01-01

    Robust maximum likelihood (RML) and asymptotically generalized least squares (AGLS) methods have been recommended for fitting ordinal structural equation models. Studies show that some of these methods underestimate standard errors. However, these studies have not investigated the coverage and bias of interval estimates. An estimate with a reasonable standard error could still be severely biased. This can only be known by systematically investigating the interval estimates. The present study compares Bayesian, RML, and AGLS interval estimates of factor correlations in ordinal confirmatory factor analysis models (CFA) for small sample data. Six sample sizes, 3 factor correlations, and 2 factor score distributions (multivariate normal and multivariate mildly skewed) were studied. Two Bayesian prior specifications, informative and relatively less informative were studied. Undercoverage of confidence intervals and underestimation of standard errors was common in non-Bayesian methods. Underestimated standard errors may lead to inflated Type-I error rates. Non-Bayesian intervals were more positive biased than negatively biased, that is, most intervals that did not contain the true value were greater than the true value. Some non-Bayesian methods had non-converging and inadmissible solutions for small samples and non-normal data. Bayesian empirical standard error estimates for informative and relatively less informative priors were closer to the average standard errors of the estimates. The coverage of Bayesian credibility intervals was closer to what was expected with overcoverage in a few cases. Although some Bayesian credibility intervals were wider, they reflected the nature of statistical uncertainty that comes with the data (e.g., small sample). Bayesian point estimates were also more accurate than non-Bayesian estimates. The results illustrate the importance of analyzing coverage and bias of interval estimates, and how ignoring interval estimates can be misleading

  13. How to Avoid Errors in Error Propagation: Prediction Intervals and Confidence Intervals in Forest Biomass

    NASA Astrophysics Data System (ADS)

    Lilly, P.; Yanai, R. D.; Buckley, H. L.; Case, B. S.; Woollons, R. C.; Holdaway, R. J.; Johnson, J.

    2016-12-01

    Calculations of forest biomass and elemental content require many measurements and models, each contributing uncertainty to the final estimates. While sampling error is commonly reported, based on replicate plots, error due to uncertainty in the regression used to estimate biomass from tree diameter is usually not quantified. Some published estimates of uncertainty due to the regression models have used the uncertainty in the prediction of individuals, ignoring uncertainty in the mean, while others have propagated uncertainty in the mean while ignoring individual variation. Using the simple case of the calcium concentration of sugar maple leaves, we compare the variation among individuals (the standard deviation) to the uncertainty in the mean (the standard error) and illustrate the declining importance in the prediction of individual concentrations as the number of individuals increases. For allometric models, the analogous statistics are the prediction interval (or the residual variation in the model fit) and the confidence interval (describing the uncertainty in the best fit model). The effect of propagating these two sources of error is illustrated using the mass of sugar maple foliage. The uncertainty in individual tree predictions was large for plots with few trees; for plots with 30 trees or more, the uncertainty in individuals was less important than the uncertainty in the mean. Authors of previously published analyses have reanalyzed their data to show the magnitude of these two sources of uncertainty in scales ranging from experimental plots to entire countries. The most correct analysis will take both sources of uncertainty into account, but for practical purposes, country-level reports of uncertainty in carbon stocks, as required by the IPCC, can ignore the uncertainty in individuals. Ignoring the uncertainty in the mean will lead to exaggerated estimates of confidence in estimates of forest biomass and carbon and nutrient contents.

  14. 6i7H8JSg

    NASA Astrophysics Data System (ADS)

    Gimeno, Teresa; O'Grady, Anthony; McVicar, Tim; Tissue, David; Ellsworth, David

    2014-05-01

    Atmospheric CO2 concentration (Ca) is rising at an unprecedented rate, nowadays nearing 400 ppm. Rising levels of Ca directly affect plant functioning and these effects cascade into all the rest of the ecosystem. A major mechanism for this is through stomatal closure in response to elevated Ca , which should result into increased soil moisture availability. The water savings lead to increased soil water storage in the deeper soil layers and ultimately increase surface runoff. The hypothesised water savings phenomenon is hotly debated, since the reduction in transpiration per unit of foliar area could be counterbalance by an increase in leaf area index (LAI) or increased understorey transpiration. To address these hypotheses, we conducted a large-scale CO2 enrichment experiment (FACE) in a water-limited ecosystem in Australia. We quantified the impact of elevated Ca on ecosystem water use and storage within the EucFACE experiment. The EucFACE experiment (Eucalyptus Free Air CO2 Enrichment) is the first of its kind established on a native old growth woodland, a remnant patch of native Cumberland plain woodland west of Sydney (Australia). The experiment consists of six 25 m diameter cylindrical arrays ('rings'). The vegetation within three of the rings is exposed to a Ca of 150 ppm above ambient. To assess the impact of elevated Ca on the different ecosystem components we monitor: soil moisture availability (from 25 to 450 cm depth), canopy transpiration (on the one major canopy forming species: Eucalyptus tereticornis), LAI, ground water oscillations, canopy interception, stemflow and understorey transpiration. We ask here whether canopy transpiration is altered by elevated Ca, and whether soil moisture dynamics have changed during the early stages of the experiment. We found reduced stomatal conductance to water vapour under elevated Ca, though this depended on soil water availability and prevailing temperature. Stomatal closure resulted in a small seasonal reduction of transpiration at the whole canopy level, only under moist conditions. Vegetation water savings under elevated Ca translated into greater moisture availability in the shallow soil during relatively moist periods whereas this effect disappeared after a sustained period without precipitation. Finally we found that during a dry period, in the deeper soil layers (200-350 cm), soil moisture gradually decreased more under ambient than under elevated Ca. Overall, these results suggest that elevated C¬a will not produce water savings during drought, but will under high and medium water availability. According to our preliminary analyses, we propose that these water savings will translate into increased soil water storage at the deeper layers.

  15. A comparison of approximate interval estimators for the Bernoulli parameter

    NASA Technical Reports Server (NTRS)

    Leemis, Lawrence; Trivedi, Kishor S.

    1993-01-01

    The goal of this paper is to compare the accuracy of two approximate confidence interval estimators for the Bernoulli parameter p. The approximate confidence intervals are based on the normal and Poisson approximations to the binomial distribution. Charts are given to indicate which approximation is appropriate for certain sample sizes and point estimators.

  16. Confidence intervals from single observations in forest research

    Treesearch

    Harry T. Valentine; George M. Furnival; Timothy G. Gregoire

    1991-01-01

    A procedure for constructing confidence intervals and testing hypothese from a single trial or observation is reviewed. The procedure requires a prior, fixed estimate or guess of the outcome of an experiment or sampling. Two examples of applications are described: a confidence interval is constructed for the expected outcome of a systematic sampling of a forested tract...

  17. Appropriate Recall Interval for Periodontal Maintenance: A Systematic Review

    PubMed Central

    Farooqi, Owais A.; Wehler, Carolyn J.; Gibson, Gretchen; Jurasic, M. Marianne; Jones, Judith A.

    2016-01-01

    Objectives A systematic review of the literature was undertaken to assess the evidence to support a specific time interval between periodontal maintenance (PM) visits. Methods Relevant articles were identified through searches in MEDLINE, EMBASE and PubMed using specific search terms, until April, 2014, resulting in 1095 abstracts and/or titles with possible relevance. Critical Appraisal Skills Programme (CASP) guidelines were used to evaluate the strength of studies and synthesize findings. If mean recall interval was not reported for study groups, authors were contacted to attempt to retrieve this information. Results Eight cohort studies met the inclusion criteria. No randomized control trials were found. All included studies assessed the effect of PM recall intervals in terms of compliance with a recommended regimen (3–6 months) as a primary outcome. Shorter PM intervals (3–6 months) favored more teeth retention but also statistically insignificant differences between RC and IC/EC, or converse findings are also found. In the 2 studies reporting mean recall interval in groups, significant tooth loss differences were noted as the interval neared the 12 month limit. Conclusions Evidence for a specific recall interval (e.g. every 3 months) for all patients following periodontal therapy is weak. Further studies, such as RCTs or large electronic database evaluations would be appropriate. The merits of risk-based recommendations over fixed recall interval regimens should be explored. PMID:26698003

  18. Sample Size for the "Z" Test and Its Confidence Interval

    ERIC Educational Resources Information Center

    Liu, Xiaofeng Steven

    2012-01-01

    The statistical power of a significance test is closely related to the length of the confidence interval (i.e. estimate precision). In the case of a "Z" test, the length of the confidence interval can be expressed as a function of the statistical power. (Contains 1 figure and 1 table.)

  19. Interval Estimation of Gamma for an "RxS" Table

    ERIC Educational Resources Information Center

    Lui, Kung-Jong; Cumberland, William G.

    2004-01-01

    When the underlying responses are on an ordinal scale, gamma is one of the most frequently used indices to measure the strength of association between two ordered variables. However, except for a brief mention on the use of the traditional interval estimator based on Wald's statistic, discussion of interval estimation of the gamma is limited.…

  20. Why Aren't They Called Probability Intervals?

    ERIC Educational Resources Information Center

    Devlin, Thomas F.

    2008-01-01

    This article offers suggestions for teaching confidence intervals, a fundamental statistical tool often misinterpreted by beginning students. A historical perspective presenting the interpretation given by their inventor is supported with examples and the use of technology. A method for determining confidence intervals for the seldom-discussed…

  1. A Comparison of Approximate Interval Estimators for the Bernoulli Parameter

    DTIC Science & Technology

    1993-12-01

    The goal of this paper is to compare the accuracy of two approximate confidence interval estimators for the Bernoulli parameter p. The approximate...is appropriate for certain sample sizes and point estimators. Confidence interval , Binomial distribution, Bernoulli distribution, Poisson distribution.

  2. Lower Confidence Interval Bounds for Coherent Systems with Cyclic Components

    DTIC Science & Technology

    1990-09-01

    Three lower confidence interval estimation procedures for system reliability of coherent systems with cyclic components are developed and their...failure times and applied to yield a lower confidence interval procedures for the reliability of coherent systems with cyclic and continuously operating components.

  3. New Confidence Interval Estimators Using Standardized Time Series.

    DTIC Science & Technology

    1984-12-01

    We develop new confidence interval estimators for the underlying mean of a stationary simulation process. These estimators can be viewed as...generalizations of Schruben’s so-called standardized time series area confidence interval estimators. Various properties of the new estimators are given.

  4. Magnitude Estimation Reveals Temporal Binding at Super-Second Intervals

    ERIC Educational Resources Information Center

    Humphreys, Gruffydd R.; Buehner, Marc J.

    2009-01-01

    Several recent studies (e.g., Haggard, Aschersleben, Gehrke, & Prinz, 2002; Haggard & Clark, 2003; Haggard, Clark, & Kalogeras, 2002) have demonstrated a "Temporal Binding" effect in which the interval between an intentional action and its consequent outcome is subjectively shorter compared to equivalent intervals that do not…

  5. Confidence Intervals for Effect Sizes: Applying Bootstrap Resampling

    ERIC Educational Resources Information Center

    Banjanovic, Erin S.; Osborne, Jason W.

    2016-01-01

    Confidence intervals for effect sizes (CIES) provide readers with an estimate of the strength of a reported statistic as well as the relative precision of the point estimate. These statistics offer more information and context than null hypothesis statistic testing. Although confidence intervals have been recommended by scholars for many years,…

  6. A neural mechanism for sensing and reproducing a time interval

    PubMed Central

    Jazayeri, Mehrdad; Shadlen, Michael N.

    2015-01-01

    SUMMARY Timing plays a crucial role in sensorimotor function. The neural mechanisms that enable the brain to flexibly measure and reproduce time intervals are however not known. We recorded neural activity in parietal cortex of monkeys in a time reproduction task. Monkeys were trained to measure and immediately afterwards reproduce different sample intervals. While measuring an interval, neural responses had a nonlinear profile that increased with the duration of the sample interval. Activity was reset during the transition from measurement to production, and was followed by a ramping activity whose slope encoded the previously measured sample interval. We found that firing rates at the end of the measurement epoch were correlated with both the slope of the ramp and the monkey’s corresponding production interval on a trial-by-trial basis. Analysis of response dynamics further linked the rate of change of firing rates in the measurement epoch to the slope of the ramp in the production epoch. These observations suggest that, during time reproduction, an interval is measured prospectively in relation to the desired motor plan to reproduce that interval. PMID:26455307

  7. Why Aren't They Called Probability Intervals?

    ERIC Educational Resources Information Center

    Devlin, Thomas F.

    2008-01-01

    This article offers suggestions for teaching confidence intervals, a fundamental statistical tool often misinterpreted by beginning students. A historical perspective presenting the interpretation given by their inventor is supported with examples and the use of technology. A method for determining confidence intervals for the seldom-discussed…

  8. Min and Max Exponential Extreme Interval Values and Statistics

    ERIC Educational Resources Information Center

    Jance, Marsha; Thomopoulos, Nick

    2009-01-01

    The extreme interval values and statistics (expected value, median, mode, standard deviation, and coefficient of variation) for the smallest (min) and largest (max) values of exponentially distributed variables with parameter ? = 1 are examined for different observation (sample) sizes. An extreme interval value g[subscript a] is defined as a…

  9. [Experimental visual evoked potentials. Interstimuli interval and cortical excitability].

    PubMed

    Díaz Calavia, E; Fernández del Moral, R; Dawid-Milner, S; Jiménez Vargas, J

    1989-01-01

    The excitability of the visual system was studied in ten adult chronic cats. Visual evoked potentials were recorded, using decreasing interstimulus intervals. A decrease of the excitability of the visual system is observed when interstimulus intervals are less than 800 milliseconds. Clinical applications with regard to visual evoked potential recording on comatose patients are suggested.

  10. Sample Size for the "Z" Test and Its Confidence Interval

    ERIC Educational Resources Information Center

    Liu, Xiaofeng Steven

    2012-01-01

    The statistical power of a significance test is closely related to the length of the confidence interval (i.e. estimate precision). In the case of a "Z" test, the length of the confidence interval can be expressed as a function of the statistical power. (Contains 1 figure and 1 table.)

  11. 30 CFR 75.360 - Preshift examination at fixed intervals.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Preshift examination at fixed intervals. 75.360 Section 75.360 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE... examination at fixed intervals. (a)(1) Except as provided in paragraph (a)(2) of this section, a certified...

  12. 30 CFR 75.360 - Preshift examination at fixed intervals.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Preshift examination at fixed intervals. 75.360 Section 75.360 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE... examination at fixed intervals. (a)(1) Except as provided in paragraph (a)(2) of this section, a certified...

  13. Reporting Confidence Intervals and Effect Sizes: Collecting the Evidence

    ERIC Educational Resources Information Center

    Zientek, Linda Reichwein; Ozel, Z. Ebrar Yetkiner; Ozel, Serkan; Allen, Jeff

    2012-01-01

    Confidence intervals (CIs) and effect sizes are essential to encourage meta-analytic thinking and to accumulate research findings. CIs provide a range of plausible values for population parameters with a degree of confidence that the parameter is in that particular interval. CIs also give information about how precise the estimates are. Comparison…

  14. A Note on Confidence Interval Estimation and Margin of Error

    ERIC Educational Resources Information Center

    Gilliland, Dennis; Melfi, Vince

    2010-01-01

    Confidence interval estimation is a fundamental technique in statistical inference. Margin of error is used to delimit the error in estimation. Dispelling misinterpretations that teachers and students give to these terms is important. In this note, we give examples of the confusion that can arise in regard to confidence interval estimation and…

  15. Confidence Intervals for Effect Sizes: Applying Bootstrap Resampling

    ERIC Educational Resources Information Center

    Banjanovic, Erin S.; Osborne, Jason W.

    2016-01-01

    Confidence intervals for effect sizes (CIES) provide readers with an estimate of the strength of a reported statistic as well as the relative precision of the point estimate. These statistics offer more information and context than null hypothesis statistic testing. Although confidence intervals have been recommended by scholars for many years,…

  16. Reporting Confidence Intervals and Effect Sizes: Collecting the Evidence

    ERIC Educational Resources Information Center

    Zientek, Linda Reichwein; Ozel, Z. Ebrar Yetkiner; Ozel, Serkan; Allen, Jeff

    2012-01-01

    Confidence intervals (CIs) and effect sizes are essential to encourage meta-analytic thinking and to accumulate research findings. CIs provide a range of plausible values for population parameters with a degree of confidence that the parameter is in that particular interval. CIs also give information about how precise the estimates are. Comparison…

  17. Overconfidence in Interval Estimates: What Does Expertise Buy You?

    ERIC Educational Resources Information Center

    McKenzie, Craig R. M.; Liersch, Michael J.; Yaniv, Ilan

    2008-01-01

    People's 90% subjective confidence intervals typically contain the true value about 50% of the time, indicating extreme overconfidence. Previous results have been mixed regarding whether experts are as overconfident as novices. Experiment 1 examined interval estimates from information technology (IT) professionals and UC San Diego (UCSD) students…

  18. Analysis of interval constants in calendars affiliated with the Shoushili

    NASA Astrophysics Data System (ADS)

    Mihn, Byeong-Hee; Lee, Ki-Won; Ahn, Young Sook

    2014-04-01

    We study interval constants that are related to motions of the Sun and Moon, i.e., the Qi, Intercalation, Revolution and Crossing interval, in calendars affiliated with the Shoushi calendar (Shoushili), such as Datongli and Chiljeongsannaepyeon. It is known that these interval constants were newly introduced in the Shoushili calendar and revised afterward, except for the Qi interval constant, and the revised values were adopted in later calendars affiliated with the Shoushili. We first investigate the accuracy of these interval constants and then the accuracy of calendars affiliated with the Shoushili in terms of these constants by comparing times for the new moon and the maximum solar eclipse calculated by each calendar with modern methods of calculation. During our study, we found that the Qi and Intercalation interval constants used in the early Shoushili were well determined, whereas the Revolution and Crossing interval constants were relatively poorly measured. We also found that the interval constants used by the early Shoushili were better than those of the later one, and hence better than those of Datongli and Chiljeongsannaepyeon. On the other hand, we found that the early Shoushili is, in general, a worse calendar than Datongli for use in China but a better one than Chiljeongsannaepyeon for use in Korea in terms of times for the new moon and when a solar eclipse occurs, at least for the period 1281 - 1644. Finally, we verified that the times for sunrise and sunset in the Shoushili-Li-Cheng and Mingshi are those at Beijing and Nanjing, respectively.

  19. Contemporary avian influenza A virus subtype H1, H6, H7, H10, and H15 hemagglutinin genes encode a mammalian virulence factor similar to the 1918 pandemic virus H1 hemagglutinin.

    PubMed

    Qi, Li; Pujanauski, Lindsey M; Davis, A Sally; Schwartzman, Louis M; Chertow, Daniel S; Baxter, David; Scherler, Kelsey; Hartshorn, Kevan L; Slemons, Richard D; Walters, Kathie-Anne; Kash, John C; Taubenberger, Jeffery K

    2014-11-18

    Zoonotic avian influenza virus infections may lead to epidemics or pandemics. The 1918 pandemic influenza virus has an avian influenza virus-like genome, and its H1 hemagglutinin was identified as a key mammalian virulence factor. A chimeric 1918 virus expressing a contemporary avian H1 hemagglutinin, however, displayed murine pathogenicity indistinguishable from that of the 1918 virus. Here, isogenic chimeric avian influenza viruses were constructed on an avian influenza virus backbone, differing only by hemagglutinin subtype expressed. Viruses expressing the avian H1, H6, H7, H10, and H15 subtypes were pathogenic in mice and cytopathic in normal human bronchial epithelial cells, in contrast to H2-, H3-, H5-, H9-, H11-, H13-, H14-, and H16-expressing viruses. Mouse pathogenicity was associated with pulmonary macrophage and neutrophil recruitment. These data suggest that avian influenza virus hemagglutinins H1, H6, H7, H10, and H15 contain inherent mammalian virulence factors and likely share a key virulence property of the 1918 virus. Consequently, zoonotic infections with avian influenza viruses bearing one of these hemagglutinins may cause enhanced disease in mammals. Influenza viruses from birds can cause outbreaks in humans and may contribute to the development of pandemics. The 1918 pandemic influenza virus has an avian influenza virus-like genome, and its main surface protein, an H1 subtype hemagglutinin, was identified as a key mammalian virulence factor. In a previous study, a 1918 virus expressing an avian H1 gene was as virulent in mice as the reconstructed 1918 virus. Here, a set of avian influenza viruses was constructed, differing only by hemagglutinin subtype. Viruses with the avian H1, H6, H7, H10, and H15 subtypes caused severe disease in mice and damaged human lung cells. Consequently, infections with avian influenza viruses bearing one of these hemagglutinins may cause enhanced disease in mammals, and therefore surveillance for human infections

  20. INTERVAL SAMPLING METHODS AND MEASUREMENT ERROR: A COMPUTER SIMULATION

    PubMed Central

    Wirth, Oliver; Slaven, James; Taylor, Matthew A.

    2015-01-01

    A simulation study was conducted to provide a more thorough account of measurement error associated with interval sampling methods. A computer program simulated the application of momentary time sampling, partial-interval recording, and whole-interval recording methods on target events randomly distributed across an observation period. The simulation yielded measures of error for multiple combinations of observation period, interval duration, event duration, and cumulative event duration. The simulations were conducted up to 100 times to yield measures of error variability. Although the present simulation confirmed some previously reported characteristics of interval sampling methods, it also revealed many new findings that pertain to each method’s inherent strengths and weaknesses. The analysis and resulting error tables can help guide the selection of the most appropriate sampling method for observation-based behavioral assessments. PMID:24127380

  1. A novel algorithm for spectral interval combination optimization.

    PubMed

    Song, Xiangzhong; Huang, Yue; Yan, Hong; Xiong, Yanmei; Min, Shungeng

    2016-12-15

    In this study, a new wavelength interval selection algorithm named as interval combination optimization (ICO) was proposed under the framework of model population analysis (MPA). In this method, the full spectra are divided into a fixed number of equal-width intervals firstly. Then the optimal interval combination is searched iteratively under the guide of MPA in a soft shrinkage manner, among which weighted bootstrap sampling (WBS) is employed as random sampling method. Finally, local search is conducted to optimize the widths of selected intervals. Three NIR datasets were used to validate the performance of ICO algorithm. Results show that ICO can select fewer wavelengths with better prediction performance when compared with other four wavelength selection methods, including VISSA, VISSA-iPLS, iVISSA and GA-iPLS. In addition, the computational intensity of ICO is also economical, benefit from fewer tune parameters and faster convergence speed. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Interval sampling methods and measurement error: a computer simulation.

    PubMed

    Wirth, Oliver; Slaven, James; Taylor, Matthew A

    2014-01-01

    A simulation study was conducted to provide a more thorough account of measurement error associated with interval sampling methods. A computer program simulated the application of momentary time sampling, partial-interval recording, and whole-interval recording methods on target events randomly distributed across an observation period. The simulation yielded measures of error for multiple combinations of observation period, interval duration, event duration, and cumulative event duration. The simulations were conducted up to 100 times to yield measures of error variability. Although the present simulation confirmed some previously reported characteristics of interval sampling methods, it also revealed many new findings that pertain to each method's inherent strengths and weaknesses. The analysis and resulting error tables can help guide the selection of the most appropriate sampling method for observation-based behavioral assessments. © Society for the Experimental Analysis of Behavior.

  3. Order and chaos in fixed-interval schedules of reinforcement

    PubMed Central

    Hoyert, Mark S.

    1992-01-01

    Fixed-interval schedule performance is characterized by high levels of variability. Responding is absent at the onset of the interval and gradually increases in frequency until reinforcer delivery. Measures of behavior also vary drastically and unpredictably between successive intervals. Recent advances in the study of nonlinear dynamics have allowed researchers to study irregular and unpredictable behavior in a number of fields. This paper reviews several concepts and techniques from nonlinear dynamics and examines their utility in predicting the behavior of pigeons responding to a fixed-interval schedule of reinforcement. The analysis provided fairly accurate a priori accounts of response rates, accounting for 92.8% of the variance when predicting response rate 1 second in the future and 64% of the variance when predicting response rates for each second over the entire next interreinforcer interval. The nonlinear dynamics account suggests that even the “noisiest” behavior might be the product of purely deterministic mechanisms. PMID:16812657

  4. Corrected profile likelihood confidence interval for binomial paired incomplete data.

    PubMed

    Pradhan, Vivek; Menon, Sandeep; Das, Ujjwal

    2013-01-01

    Clinical trials often use paired binomial data as their clinical endpoint. The confidence interval is frequently used to estimate the treatment performance. Tang et al. (2009) have proposed exact and approximate unconditional methods for constructing a confidence interval in the presence of incomplete paired binary data. The approach proposed by Tang et al. can be overly conservative with large expected confidence interval width (ECIW) in some situations. We propose a profile likelihood-based method with a Jeffreys' prior correction to construct the confidence interval. This approach generates confidence interval with a much better coverage probability and shorter ECIWs. The performances of the method along with the corrections are demonstrated through extensive simulation. Finally, three real world data sets are analyzed by all the methods. Statistical Analysis System (SAS) codes to execute the profile likelihood-based methods are also presented.

  5. BIOCHEMISTRY PANEL REFERENCE INTERVALS FOR JUVENILE GOLDFISH (CARASSIUS AURATUS).

    PubMed

    Adamovicz, Laura A; Trosclair, Macy R; Lewbart, Gregory A

    2017-09-01

    Reference intervals for diagnostic tests are vitally important for clinical decision making. Despite the popularity of pet goldfish (Carassius auratus), reference intervals have not been generated for routine biochemistry panel analytes in this species. This study establishes de novo reference intervals for packed cell volume and total solids, using 47 apparently healthy immature goldfish, and for 11 common chemistry panel analytes (albumin, aspartate aminotransferase, calcium, creatine kinase, globulin, blood glucose, sodium, potassium, phosphorous, total protein, and uric acid) using 39 immature goldfish. Robust reference intervals were generated following recommendations of the American Society for Veterinary Clinical Pathology. Linear regression was used to demonstrate a statistically significant relationship between body weight and calcium, albumin, total protein, potassium, packed cell volume, and total solids. The results of this study serve as a useful baseline for future reference interval generation in goldfish.

  6. Exact confidence intervals for channelized Hotelling observer performance

    NASA Astrophysics Data System (ADS)

    Wunderlich, Adam; Noo, Frederic; Heilbrun, Marta

    2013-03-01

    Task-based assessments of image quality constitute a rigorous, principled approach to the evaluation of imaging system performance. To conduct such assessments, it has been recognized that mathematical model observers are very useful, particularly for purposes of imaging system development and optimization. One type of model observer that has been widely applied in the medical imaging community is the channelized Hotelling observer (CHO). In the present work, we address the need for reliable confidence interval estimators of CHO performance. Specifically, we observe that a procedure proposed by Reiser for interval estimation of the Mahalanobis distance can be applied to obtain confidence intervals for CHO performance. In addition, we find that these intervals are well-defined with theoretically-exact coverage probabilities, which is a new result not proved by Reiser. The confidence intervals are tested with Monte Carlo simulation and demonstrated with an example comparing x-ray CT reconstruction strategies.

  7. Timing Intervals Using Population Synchrony and Spike Timing Dependent Plasticity

    PubMed Central

    Xu, Wei; Baker, Stuart N.

    2016-01-01

    We present a computational model by which ensembles of regularly spiking neurons can encode different time intervals through synchronous firing. We show that a neuron responding to a large population of convergent inputs has the potential to learn to produce an appropriately-timed output via spike-time dependent plasticity. We explain why temporal variability of this population synchrony increases with increasing time intervals. We also show that the scalar property of timing and its violation at short intervals can be explained by the spike-wise accumulation of jitter in the inter-spike intervals of timing neurons. We explore how the challenge of encoding longer time intervals can be overcome and conclude that this may involve a switch to a different population of neurons with lower firing rate, with the added effect of producing an earlier bias in response. Experimental data on human timing performance show features in agreement with the model's output. PMID:27990109

  8. Changes in QT interval before and after hemodialysis

    PubMed Central

    Khosoosi Niaki, Mohammad Reza; Saravi, Mehrdad; Oliaee, Farshid; Akbari, Roghayeh; Noorkhomami, Sepideh; Bozorgi Rad, Seyed Hassan; Fallahpoor, Kobra; Ramezani, Mir Saeed

    2013-01-01

    Background: Cardiovascular mortality and morbidity are high in chronic renal failure (CRF) patients. Increased dispersion of QT intervals is known to predispose to ventricular arrhythmias and sudden cardiac death. This study was conducted to assess the effect of hemodialysis (HD) on corrected QT (QTc) intervals and their dispersions (QTd) in chronic hemodialyzed patients. Methods: Fifty-eight patients ( mean age 54.2±15.8 years) with chronic renal disease on chronic hemodialysis (HD) were assessed by standard examination including blood pressure, body weight, heart rate, 12–lead electrocardiography and laboratory tests like electrolytes (Na +, K +, Ca ++, phosphate), urea, and creatinine 30 minutes before and after HD. The QT intervals and QTc QTc= QT √R-R/ (in milli seconds [ms]) for each lead were measured manually by one observer using calipers. The difference between the maximum and the minimum of QT interval was noted as QT dispersion (QT d). Results: The mean of pre and post dialysis R-R intervals was 859.22±96.85 ms and 870.43±91.45 ms, respectively (p>0.05). The mean of corrected QT cmax intervals increased significantly from 423.45±24.10 to 454.41±30.25 ms (p<0.05). The mean of QT dispersions and the corrected QT interval dispersions changed from 51.56±12.45 to 63.21±14.43 ms (p<0.05) from 59.40±13.58 to 68.33±14.55 ms (p<0.05), respectively. The changes in serum potassium and calcium levels were related with QT interval prolongation. Conclusion: QT and QTc interval and dispersion increase in HD patients. Prolonged QT interval indices had relation with K+ and Ca++ ions before but not after HD. PMID:24009942

  9. Gender differences in the dynamics of terminal T wave intervals.

    PubMed

    Nakagawa, Mikiko; Ooie, Tatsuhiko; Ou, Baiqing; Ichinose, Masashi; Yonemochi, Hidetoshi; Saikawa, Tetsunori

    2004-06-01

    This study was designed to investigate gender differences in the dynamic changes of the terminal T wave (Ta-e interval) of healthy subjects. Holter ECGs were recorded in 24 healthy volunteers (12 men aged 23 +/- 2 years). The intervals from QRS onset to the apex (QaT) and to the end of the T wave (QeT), and the interval between the apex and the end of the T wave (Ta-e) were measured. Then, the QeT/RR, QaT/RR, and Ta-e/RR relationship was evaluated by linear regression analysis in each subject. The QeT and QaT intervals were significantly longer in women than men and the slope of the QeT/RR and QaT/RR relationship was steeper in women than men. The Ta-e intervals showed a significant but weaker positive correlation with the preceding RR intervals in 7 (58.3%) men and 9 (75.0%) women. The average values of the slope and the correlation coefficient of the Ta-e/RR relationship were significantly smaller compared to those of QeT and QaT in both men and women (P < 0.0001). The slope of the Ta-e/RR relationship was significantly greater in women than men (0.025 +/- 0.009 vs 0.011 +/- 0.012, P < 0.005). However, the Ta-e intervals were significantly longer over the entire range of RR intervals in men than women (P < 0.0001). The rate-correcting formulas of Bazett and Framingham overcorrected the Ta-e intervals. The observed gender difference in the measurement and dynamics of the Ta-e interval may help to understand the mechanisms underlying the gender difference in the incidence of ventricular arrhythmias.

  10. Drug discrimination under two concurrent fixed-interval fixed-interval schedules.

    PubMed

    McMillan, D E; Li, M

    2000-07-01

    Pigeons were trained to discriminate 5.0 mg/kg pentobarbital from saline under a two-key concurrent fixed-interval (FI) 100-s FI 200-s schedule of food presentation, and later tinder a concurrent FI 40-s FI 80-s schedule, in which the FI component with the shorter time requirement reinforced responding on one key after drug administration (pentobarbital-biased key) and on the other key after saline administration (saline-biased key). After responding stabilized under the concurrent FI 100-s FI 200-s schedule, pigeons earned an average of 66% (after pentobarbital) to 68% (after saline) of their reinforcers for responding under the FI 100-s component of the concurrent schedule. These birds made an average of 70% of their responses on both the pentobarbital-biased key after the training dose of pentobarbital and the saline-biased key after saline. After responding stabilized under the concurrent FI 40-s FI 80-s schedule, pigeons earned an average of 67% of their reinforcers for responding under the FI 40 component after both saline and the training dose of pentobarbital. These birds made an average of 75% of their responses on the pentobarbital-biased key after the training dose of pentobarbital, but only 55% of their responses on the saline-biased key after saline. In test sessions preceded by doses of pentobarbital, chlordiazepoxide, ethanol, phencyclidine, or methamphetamine, the dose-response curves were similar under these two concurrent schedules. Pentobarbital, chlordiazepoxide, and ethanol produced dose-dependent increases in responding on the pentobarbital-biased key as the doses increased. For some birds, at the highest doses of these drugs, the dose-response curve turned over. Increasing doses of phencyclidine produced increased responding on the pentobarbital-biased key in some, but not all, birds. After methamphetamine, responding was largely confined to the saline-biased key. These data show that pigeons can perform drug discriminations under concurrent

  11. Drug discrimination under two concurrent fixed-interval fixed-interval schedules.

    PubMed Central

    McMillan, D E; Li, M

    2000-01-01

    Pigeons were trained to discriminate 5.0 mg/kg pentobarbital from saline under a two-key concurrent fixed-interval (FI) 100-s FI 200-s schedule of food presentation, and later tinder a concurrent FI 40-s FI 80-s schedule, in which the FI component with the shorter time requirement reinforced responding on one key after drug administration (pentobarbital-biased key) and on the other key after saline administration (saline-biased key). After responding stabilized under the concurrent FI 100-s FI 200-s schedule, pigeons earned an average of 66% (after pentobarbital) to 68% (after saline) of their reinforcers for responding under the FI 100-s component of the concurrent schedule. These birds made an average of 70% of their responses on both the pentobarbital-biased key after the training dose of pentobarbital and the saline-biased key after saline. After responding stabilized under the concurrent FI 40-s FI 80-s schedule, pigeons earned an average of 67% of their reinforcers for responding under the FI 40 component after both saline and the training dose of pentobarbital. These birds made an average of 75% of their responses on the pentobarbital-biased key after the training dose of pentobarbital, but only 55% of their responses on the saline-biased key after saline. In test sessions preceded by doses of pentobarbital, chlordiazepoxide, ethanol, phencyclidine, or methamphetamine, the dose-response curves were similar under these two concurrent schedules. Pentobarbital, chlordiazepoxide, and ethanol produced dose-dependent increases in responding on the pentobarbital-biased key as the doses increased. For some birds, at the highest doses of these drugs, the dose-response curve turned over. Increasing doses of phencyclidine produced increased responding on the pentobarbital-biased key in some, but not all, birds. After methamphetamine, responding was largely confined to the saline-biased key. These data show that pigeons can perform drug discriminations under concurrent

  12. Ocular Hypotensive Response in Nonhuman Primates of (8R)-1-[(2S)-2-Aminopropyl]-8,9-dihydro-7H-pyrano[2,3-g]indazol-8-ol a Selective 5-HT2 Receptor Agonist.

    PubMed

    May, Jesse A; Sharif, Najam A; McLaughlin, Marsha A; Chen, Hwang-Hsing; Severns, Bryon S; Kelly, Curtis R; Holt, William F; Young, Richard; Glennon, Richard A; Hellberg, Mark R; Dean, Thomas R

    2015-11-25

    Recently, it has been reported that 5-HT2 receptor agonists effectively reduce intraocular pressure (IOP) in a nonhuman primate model of glaucoma. Although 1-[(2S)-2-aminopropyl]indazol-6-ol (AL-34662) was shown to have good efficacy in this nonhuman primate model of ocular hypertension as well as a desirable physicochemical and permeability profile, subsequently identified cardiovascular side effects in multiple species precluded further clinical evaluation of this compound. Herein, we report selected structural modifications that resulted in the identification of (8R)-1-[(2S)-2-aminopropyl]-8,9-dihydro-7H-pyrano[2,3-g]indazol-8-ol (13), which displayed an acceptable profile to support advancement for further preclinical evaluation as a candidate for proof-of-concept studies in humans.

  13. Efficient Catalyst One-Pot Synthesis of 7-(Aryl)-10,10-dimethyl-10,11-dihydrochromeno[4,3-b]chromene-6,8(7H,9H)-dione Derivatives Complemented by Antibacterial Activity

    PubMed Central

    Al-Majedy, Yasameen K.; Kadhum, Abdul Amir H.; Mohamad, Abu Bakar

    2016-01-01

    The problem of bacteria resistance to many known agents has inspired scientists and researchers to discover novel efficient antibacterial drugs. Three rapid, clean, and highly efficient methods were developed for one-pot synthesis of 7-(aryl)-10,10-dimethyl-10,11-dihydrochromeno[4,3-b]chromene-6,8(7H,9H)-dione derivatives. Three components are condensed in the synthesis, 4-hydroxycoumarin, 5,5-dimethyl-1,3-cyclohexanedione, and aromatic aldehydes, using tetrabutylammonium bromide (TBAB), diammonium hydrogen phosphate (DAHP), or ferric chloride (FeCl3), respectively. Each method has different reaction mechanisms according to the catalyst. The present methods have advantages, including one-pot synthesis, excellent yields, short reaction times, and easy isolation of product. All catalysts utilized in our study could be reused several times without losing their catalytic efficiency. All synthesized compounds were fully characterized and evaluated for their antibacterial activity. PMID:27563671

  14. Crystal structure of 6,9-dimethyl-7H-[1,2,4]triazolo[4,3-b][1,2,4]triazepin-8(9H)-one 0.40-hydrate

    PubMed Central

    Harmaoui, Abdellah; Bouhfid, Rachid; Essassi, El Mokhtar; Saadi, Mohamed; El Ammari, Lahcen

    2015-01-01

    In the mol­ecule of the title compound, C7H9N5O·0.40H2O, the seven-membered heterocyclic ring exhibits a boat conformation, whereas the five-membered triazole ring is almost planar (r.m.s. deviation = 0.005 Å). In the crystal, centrosymmetric dimers are linked by pairs of C—H⋯O hydrogen bonds into dimers, which are further connected via O—H⋯N and C—H⋯N hydrogen bonds, forming a three-dimensional network. The structure contains a partially occupied water mol­ecule lying on a twofold axis with an occupancy factor of 0.4. PMID:25705477

  15. Gapless spin liquid ground state in the S = 1/2 vanadium oxyfluoride kagome antiferromagnet [NH4]2[C7H14N][V7O6F18].

    PubMed

    Clark, L; Orain, J C; Bert, F; De Vries, M A; Aidoudi, F H; Morris, R E; Lightfoot, P; Lord, J S; Telling, M T F; Bonville, P; Attfield, J P; Mendels, P; Harrison, A

    2013-05-17

    The vanadium oxyfluoride [NH(4)](2)[C(7)H(14)N][V(7)O(6)F(18)] (DQVOF) is a geometrically frustrated magnetic bilayer material. The structure consists of S = 1/2 kagome planes of V(4+) d(1) ions with S = 1 V(3+) d(2) ions located between the kagome layers. Muon spin relaxation measurements demonstrate the absence of spin freezing down to 40 mK despite an energy scale of 60 K for antiferromagnetic exchange interactions. From magnetization and heat capacity measurements we conclude that the S = 1 spins of the interplane V(3+) ions are weakly coupled to the kagome layers, such that DQVOF can be viewed as an experimental model for S = 1/2 kagome physics, and that it displays a gapless spin liquid ground state.

  16. Crystal structure of 6,9-dimethyl-7H-[1,2,4]triazolo[4,3-b][1,2,4]triazepin-8(9H)-one 0.40-hydrate.

    PubMed

    Harmaoui, Abdellah; Bouhfid, Rachid; Essassi, El Mokhtar; Saadi, Mohamed; El Ammari, Lahcen

    2015-01-01

    In the mol-ecule of the title compound, C7H9N5O·0.40H2O, the seven-membered heterocyclic ring exhibits a boat conformation, whereas the five-membered triazole ring is almost planar (r.m.s. deviation = 0.005 Å). In the crystal, centrosymmetric dimers are linked by pairs of C-H⋯O hydrogen bonds into dimers, which are further connected via O-H⋯N and C-H⋯N hydrogen bonds, forming a three-dimensional network. The structure contains a partially occupied water mol-ecule lying on a twofold axis with an occupancy factor of 0.4.

  17. Intonation of musical intervals by musical intervals by deaf subjects stimulated with single bipolar cochlear implant electrodes.

    PubMed

    Pijl, S; Schwarz, D W

    1995-09-01

    Some subjects with cochlear implants have been shown to associate electrical stimulus pulse rates with the pitches of musical tones. In order to clarify the role of these pitch sensations in a musical context, the present investigation examined the intonation accuracy achieved by implant subjects when adjusting pulse rates in the reconstruction of musical intervals. Using a method of adjustment, the subjects altered a variable pulse rate, relative to a fixed reference rate, on one electrode, in the tuning of musical intervals abstracted from familiar melodies. At low pulse rates, subjects generally tuned the intervals to the same frequency ratios which define tonal musical intervals in normal-hearing listeners, with error margins comparable to musically untrained subjects. Two subjects were, in addition, able to transpose these melodic intervals from a standard reference pulse rate to higher and lower reference rates (reference and target pulse rates with geometric means of the intervals ranging from 81 to 466 pulses/s). Generally, the intervals were adjusted on a ratio scale, according to the same frequency ratios which define analogous acoustical musical intervals. These results support the hypothesis that, at low pulse rates, a temporal code in the auditory nerve alone is capable of defining musical pitch.

  18. Predicting fecal coliform using the interval-to-interval approach and SWAT in the Miyun watershed, China.

    PubMed

    Bai, Jianwen; Shen, Zhenyao; Yan, Tiezhu; Qiu, Jiali; Li, Yangyang

    2017-06-01

    Pathogens in manure can cause waterborne-disease outbreaks, serious illness, and even death in humans. Therefore, information about the transformation and transport of bacteria is crucial for determining their source. In this study, the Soil and Water Assessment Tool (SWAT) was applied to simulate fecal coliform bacteria load in the Miyun Reservoir watershed, China. The data for the fecal coliform were obtained at three sampling sites, Chenying (CY), Gubeikou (GBK), and Xiahui (XH). The calibration processes of the fecal coliform were conducted using the CY and GBK sites, and validation was conducted at the XH site. An interval-to-interval approach was designed and incorporated into the processes of fecal coliform calibration and validation. The 95% confidence interval of the predicted values and the 95% confidence interval of measured values were considered during calibration and validation in the interval-to-interval approach. Compared with the traditional point-to-point comparison, this method can improve simulation accuracy. The results indicated that the simulation of fecal coliform using the interval-to-interval approach was reasonable for the watershed. This method could provide a new research direction for future model calibration and validation studies.

  19. Structure-5-HT/D2 Receptor Affinity Relationship in a New Group of 1-Arylpiperazynylalkyl Derivatives of 8-Dialkylamino-3,7-dimethyl-1H-purine-2,6(3H,7H)-dione.

    PubMed

    Żmudzki, Paweł; Satała, Grzegorz; Chłoń-Rzepa, Grażyna; Bojarski, Andrzej J; Kazek, Grzegorz; Siwek, Agata; Gryboś, Anna; Głuch-Lutwin, Monika; Wesołowska, Anna; Pawłowski, Maciej

    2016-10-01

    In our previous papers, we have reported that some 8-amino-1,3-dimethyl-1H-purine-2,6(3H,7H)-dione derivatives possessed high affinity and displayed agonistic, partial agonistic, or antagonistic activity for serotonin 5-HT1A and dopamine D2 receptors. In order to examine further the influence of the substituent in the position 8 of the purine moiety and the influence of the xanthine core on the affinity for serotonin 5-HT1A , 5-HT2A , 5-HT6 , 5-HT7 , and dopamine D2 receptors, two series of 1-arylpiperazynylalkyl derivatives of 8-amino-3,7-dimethyl-1H-purine-2,6(3H,7H)-dione were synthesized. All the final compounds were investigated in in vitro competition binding experiments for the serotonin 5-HT1A , 5-HT2A , 5-HT6 , 5-HT7 , and dopamine D2 receptors. The structure-affinity relationships for this group of compounds were discussed. For selected compounds, the functional assays for the 5-HT1A and D2 receptors were carried out. The results of the assays indicated that these groups of derivatives possessed antagonistic activity for 5-HT1A receptors and agonistic, partial agonistic, or antagonistic activity for D2 receptors. In total, 26 new compounds were synthesized, 20 of which were tested in in vitro binding experiments and 5 were tested in in vitro functional assays. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Interaction between respiratory and RR interval oscillations at low frequencies.

    PubMed

    Aguirre, A; Wodicka, G R; Maayan, C; Shannon, D C

    1990-03-01

    Oscillations in RR interval between 0.02 and 1.00 cycles per second (Hz) have been related to the action of the autonomic nervous system. Respiration has been shown to influence RR interval at normal breathing frequencies between approximately 0.16 and 0.5 Hz in children and adults--a phenomenon known as respiratory sinus arrhythmia. In this study we investigated the effect of respiration on RR interval in a lower frequency range between 0.02 and 0.12 Hz. Low frequency oscillations in respiration were induced in healthy sleeping adult subjects via the administration of a bolus of CO2 during inhalation. Power spectra of RR interval and respiration were obtained before and after the CO2 pulse, and the frequency content in the low frequency range was quantitatively compared. An increase in the spectral energy in both respiration and RR interval was observed for the group. However, this increase was accounted for by six of 29 epochs. We conclude that respiration (tidal volume) can influence RR interval at frequencies below those usually associated with respiratory sinus arrhythmia. This influence may be mediated through a sympathetic reflex. This result is applicable to the measurement and interpretation of heart rate variability and to autonomic influences of low frequency fluctuations in RR interval.

  1. Modelling volatility recurrence intervals in the Chinese commodity futures market

    NASA Astrophysics Data System (ADS)

    Zhou, Weijie; Wang, Zhengxin; Guo, Haiming

    2016-09-01

    The law of extreme event occurrence attracts much research. The volatility recurrence intervals of Chinese commodity futures market prices are studied: the results show that the probability distributions of the scaled volatility recurrence intervals have a uniform scaling curve for different thresholds q. So we can deduce the probability distribution of extreme events from normal events. The tail of a scaling curve can be well fitted by a Weibull form, which is significance-tested by KS measures. Both short-term and long-term memories are present in the recurrence intervals with different thresholds q, which denotes that the recurrence intervals can be predicted. In addition, similar to volatility, volatility recurrence intervals also have clustering features. Through Monte Carlo simulation, we artificially synthesise ARMA, GARCH-class sequences similar to the original data, and find out the reason behind the clustering. The larger the parameter d of the FIGARCH model, the stronger the clustering effect is. Finally, we use the Fractionally Integrated Autoregressive Conditional Duration model (FIACD) to analyse the recurrence interval characteristics. The results indicated that the FIACD model may provide a method to analyse volatility recurrence intervals.

  2. Fixed-interval performance and self-control in children.

    PubMed

    Darcheville, J C; Rivière, V; Wearden, J H

    1992-03-01

    Operant responses of 16 children (mean age 6 years and 1 month) were reinforced according to different fixed-interval schedules (with interreinforcer intervals of 20, 30, or 40 s) in which the reinforcers were either 20-s or 40-s presentations of a cartoon. In another procedure, they received training on a self-control paradigm in which both reinforcer delay (0.5 s or 40 s) and reinforcer duration (20 s or 40 s of cartoons) varied, and subjects were offered a choice between various combinations of delay and duration. Individual differences in behavior under the self-control procedure were precisely mirrored by individual differences under the fixed-interval schedule. Children who chose the smaller immediate reinforcer on the self-control procedure (impulsive) produced short postreinforcement pauses and high response rates in the fixed-interval conditions, and both measures changed little with changes in fixed-interval value. Conversely, children who chose the larger delayed reinforcer in the self-control condition (the self-controlled subjects) exhibited lower response rates and long postreinforcement pauses, which changed systematically with changes in the interval, in their fixed-interval performances.

  3. Recommended tests and confidence intervals for paired binomial proportions.

    PubMed

    Fagerland, Morten W; Lydersen, Stian; Laake, Petter

    2014-07-20

    We describe, evaluate, and recommend statistical methods for the analysis of paired binomial proportions. A total of 24 methods are considered. The best tests for association include the asymptotic McNemar test and the McNemar mid- p test. For the difference between proportions, we recommend two simple confidence intervals with closed-form expressions and the asymptotic score interval. The asymptotic score interval is also recommended for the ratio of proportions, as is an interval with closed-form expression based on combining two Wilson score intervals for the single proportion. For the odds ratio, we recommend a transformation of the Wilson score interval and a transformation of the Clopper-Pearson mid- p interval. We illustrate the practical application of the methods using data from a recently published study of airway reactivity in children before and after stem cell transplantation and a matched case-control study of the association between floppy eyelid syndrome and obstructive sleep apnea-hypopnea syndrome.

  4. Planetary period oscillations in Saturn's magnetosphere: Comparison of magnetic oscillations and SKR modulations in the postequinox interval

    NASA Astrophysics Data System (ADS)

    Provan, G.; Lamy, L.; Cowley, S. W. H.; Dougherty, M. K.

    2014-09-01

    We compare the properties of planetary period oscillations observed in Saturn kilometric radiation (SKR) and magnetospheric magnetic field data from Saturn equinox in August 2009 to July 2013. As shown previously, the southern and northern oscillation periods converged across equinox from ~10.8 h and ~10.6 h, respectively, during southern summer, to closely common values ~10.7 h approximately 1 year after equinox. Near coalescence is judged to have occurred approximately 3 months earlier in the SKR data, centered in late June 2010, than in the magnetic data, in late September, though SKR periods were particularly difficult to determine during this interval due to less clearly modulated emissions. Both data sets agree, however, that by early November 2010 the two periods had separated again but remained closely spaced with a difference in period of ~3 min about a mean of ~10.67 h, with the southern period remaining longer than the northern. Thus, no enduring reversal of the northern and southern periods took place following near coalescence in mid-2010, the periods remaining uncrossed to the end of the interval studied here. The SKR modulations also show effects related to the sharp amplitude changes observed in the magnetic oscillation data at ~100-200 day intervals since February 2011, though the correspondences are not exact, indicating that other factors such as "seeing" effects on the variable Cassini orbit are also involved. Postequinox variations in the relative phase between the magnetic and SKR oscillations are also shown to be related to changes in orbit apoapsis orientation.

  5. Abnormal vascular function in PR-interval prolongation.

    PubMed

    Chan, Yap-Hang; Siu, Chung-Wah; Yiu, Kai-Hang; Li, Sheung-Wai; Lau, Kui-Kai; Lam, Tai-Hing; Lau, Chu-Pak; Tse, Hung-Fat

    2011-10-01

    Underlying mechanisms of PR-interval prolongation leading to increased risk of adverse cardiovascular outcomes, including atrial fibrillation, are unclear. This study aims to investigate the relation between PR interval and changes in vascular function. We hypothesize that there exists an intermediate pathological stage between electrocardiographic PR prolongation and adverse cardiovascular outcomes, which could be reflected by changes in surrogate measurements of vascular function. We recruited 88 healthy subjects (mean age 57.5 ± 9.8 y, 46% male) from a community-based health screening program who had no history of cardiovascular disease or diabetes mellitus. PR interval was determined from a resting 12-lead electrocardiogram. Vascular function was noninvasively assessed by flow-mediated dilation (FMD) using high-resolution ultrasound and brachial-ankle pulse wave velocity (PWV) using a vascular profiling system. Only 3 subjects had a PR-interval length longer than the conventional cutoff of 200 ms. The PR-interval length was associated inversely with FMD (Pearson r = -0.30, P = 0.004) and positively with PWV (r = 0.40, P < 0.001). Adjusting for potential confounders, increased PR-interval length by each 25 ms was independently associated with reduced FMD by -1 unit (absolute %, B = -0.04 [95% confidence interval: -0.080 to -0.002, P = 0.040)] and increased PWV by +103 cm/second (B = +4.1 [95% confidence interval: 0.6-7.6, P = 0.023]). This study shows that PR-interval length, even in the conventionally normal range, is independently associated with endothelial dysfunction and increased arterial stiffness in healthy subjects free of atherosclerotic disease. This suggests the presence of a systemic, intermediate pathologic stage of the vasculature in PR prolongation before clinically manifest cardiovascular events, and could represent a mediating mechanism. © 2011 Wiley Periodicals, Inc.

  6. Effect of resting interval for muscle regeneration in mice.

    PubMed

    Sasaki, Aizawa; Aizawa, Toshimi; Tomiya, Akihito; Matsubara, Yoshihiro; Kokubun, Shoichi; Itoi, Eiji

    2007-01-01

    Muscle tissue has an exceptional ability to regenerate, however, unresting damage to the muscles by intense and frequent exercises occasionally causes prolonged muscle fatigue, soreness, and underperformance in sports. Taking rest is generally considered to be crucial for regular training to avoid the accumulation of muscle damage. We hypothesized that differences in the resting intervals between two periods of exercise may result in histological differences in muscle regeneration. An eccentric contraction model of mouse gastrocnemius muscle was made using percutaneus electrical stimulation. The mice received eccentric exercises twice with resting intervals of 0, 12, 24 hours, 2, and 3 days. The authors investigated the ratio of myofibers with central nuclei to whole myofibers histologically (the centronuclear cell ratio; CNCR) at 14 days after the second exercise as an index of the muscle regeneration. The CNCR of the group that exercised one-time was 29.5%. In the groups exercised twice, it increased from 31.8% with an interval of 0 hours to a peak of 43.9% with 24 hours, then decreased to 32.8% with an interval of 3 days. The ratios of the groups with intervals of 12 and 24 hours were higher than those with one-time exercise and those with the intervals of 0 hours, 2 days, and 3 days. The resting interval between two periods of eccentric exercises affected the histology of muscle regeneration. The amount of muscle damage and/or the recovery process of damaged muscles should vary depending on the length of resting interval between strenuous exercises. An appropriate interval for rest must be necessary in order to avoid further muscle damage.

  7. Concept of Operations for Interval Management Arrivals and Approach

    NASA Technical Reports Server (NTRS)

    Hicok, Daniel S.; Barmore, Bryan E.

    2016-01-01

    This paper presents the concept of operations for interval management operations to be deployed in the US National Airspace System (NAS) by the Federal Aviation Administration (FAA) after 2020. The use of interval management operations is described that begin in en route airspace and continue to a termination point inside the arrival terminal area, in a terminal environment that includes other arrival management tools such as arrival metering, Ground-based Interval Management - Spacing (GIM-S), and Terminal Sequencing and Spacing (TSAS). The roles of Air Traffic Controllers and Flight Crews and the ground automation tools that are used by Air Traffic Controllers to enable the primary operation and variations are described.

  8. Small Sample Theory for Steady State Confidence Intervals

    DTIC Science & Technology

    1989-06-01

    confidence interval for the mean of a stationary sequence. As indicated in the literature, nonparametric confidence intervals in practice often have undesirable small-sample asymmetry and coverage characteristics. These phenomena are partially due to the fact that the third and fourth cumulants of the point estimator for the stationary mean, unlike those of the standard normal random variable, are not zero. We will apply Edgeworth and Cornish-Fisher expansions to obtain asymptotic expansions for the errors associated with confidence intervals. The analysis isolates various

  9. Operating Procedures for Precise Time and Time Interval Equipments

    DTIC Science & Technology

    1981-02-12

    amber, or green screw-base lens. In case of failure, pull out the bulb from the lens by means of the flange ring on the base of the bulb. Do not...using the time interval counter, terminate the 5061A 1 pps output cable with a 50-ohm load to minimize pulse ringing . d. When using a time interval...the time in- terval counter, terminate the 5062C 1 pps output cable with a 50-ohm load to minimize pulse ringing . b. When using a time interval

  10. The Role of Higher Harmonics In Musical Interval Perception

    NASA Astrophysics Data System (ADS)

    Krantz, Richard; Douthett, Jack

    2011-10-01

    Using an alternative parameterization of the roughness curve we make direct use of critical band results to investigate the role of higher harmonics on the perception of tonal consonance. We scale the spectral amplitudes in the complex home tone and complex interval tone to simulate acoustic signals of constant energy. Our analysis reveals that even with a relatively small addition of higher harmonics the perfect fifth emerges as a consonant interval with more, musically important, just intervals emerging as consonant as more and more energy is shifted into higher frequencies.

  11. Estimation of confidence intervals for federal waterfowl harvest surveys

    USGS Publications Warehouse

    Geissler, P.H.

    1990-01-01

    I developed methods of estimating confidence intervals for the federal waterfowl harvest surveys conducted by the U.S. Fish and Wildlife Service (USFWS). I estimated flyway harvest confidence intervals for mallards (Anas platyrhynchos) (95% CI are .+-. 8% of the estimate). Canada geese (Branta canadensis) (.+-. 11%), black ducks (Anas rubripes) (.+-. 16%), canvasbacks (Aythya valisineria) (.+-. 32%), snow geese (Chen caerulescens) (.+-. 43%), and brant (Branta bernicla) (.+-. 46%). Differences between annual estimate of 10, 13, 22, 42, 43, and 58% could be detected with mallards, Canada geese, black ducks, canvasbacks, snow geese, and brant, respectively. Estimated confidence intervals for state harvests tended to be much larger than those for the flyway estimates.

  12. Establishing maintenance intervals based on measurement reliability of engineering endpoints.

    PubMed

    James, P J

    2000-01-01

    Methods developed by the metrological community and principles used by the research community were integrated to provide a basis for a periodic maintenance interval analysis system. Engineering endpoints are used as measurement attributes on which to base two primary quality indicators: accuracy and reliability. Also key to establishing appropriate maintenance intervals is the ability to recognize two primary failure modes: random failure and time-related failure. The primary objective of the maintenance program is to avert predictable and preventable device failure, and understanding time-related failures enables service personnel to set intervals accordingly.

  13. Venlafaxine induced QTc interval prolongation in a therapeutic dose.

    PubMed

    Bavle, Amar

    2015-08-01

    This is the second report of a patient developing severe prolongation of QTc interval with a dose of 300mg/day of venlafaxine; on stopping it, QTc reverted to normalcy. Venlafaxine was restarted and maintained at 150mg/day, with QTc interval remaining normal, indicating, that it has a dose-dependent effect on QTc interval. Venlafaxine was not changed as she had responded best to this drug compared to any other antidepressant. Over 20 years, the only time she had a period of 5 years of remission, was when she was on 75mg of venlafaxine/day. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Detectability of auditory signals presented without defined observation intervals

    NASA Technical Reports Server (NTRS)

    Watson, C. S.; Nichols, T. L.

    1976-01-01

    Ability to detect tones in noise was measured without defined observation intervals. Latency density functions were estimated for the first response following a signal and, separately, for the first response following randomly distributed instances of background noise. Detection performance was measured by the maximum separation between the cumulative latency density functions for signal-plus-noise and for noise alone. Values of the index of detectability, estimated by this procedure, were approximately those obtained with a 2-dB weaker signal and defined observation intervals. Simulation of defined- and non-defined-interval tasks with an energy detector showed that this device performs very similarly to the human listener in both cases.

  15. Detectability of auditory signals presented without defined observation intervals

    NASA Technical Reports Server (NTRS)

    Watson, C. S.; Nichols, T. L.

    1976-01-01

    Ability to detect tones in noise was measured without defined observation intervals. Latency density functions were estimated for the first response following a signal and, separately, for the first response following randomly distributed instances of background noise. Detection performance was measured by the maximum separation between the cumulative latency density functions for signal-plus-noise and for noise alone. Values of the index of detectability, estimated by this procedure, were approximately those obtained with a 2-dB weaker signal and defined observation intervals. Simulation of defined- and non-defined-interval tasks with an energy detector showed that this device performs very similarly to the human listener in both cases.

  16. A new method for wavelength interval selection that intelligently optimizes the locations, widths and combinations of the intervals.

    PubMed

    Deng, Bai-Chuan; Yun, Yong-Huan; Ma, Pan; Lin, Chen-Chen; Ren, Da-Bing; Liang, Yi-Zeng

    2015-03-21

    In this study, a new algorithm for wavelength interval selection, known as interval variable iterative space shrinkage approach (iVISSA), is proposed based on the VISSA algorithm. It combines global and local searches to iteratively and intelligently optimize the locations, widths and combinations of the spectral intervals. In the global search procedure, it inherits the merit of soft shrinkage from VISSA to search the locations and combinations of informative wavelengths, whereas in the local search procedure, it utilizes the information of continuity in spectroscopic data to determine the widths of wavelength intervals. The global and local search procedures are carried out alternatively to realize wavelength interval selection. This method was tested using three near infrared (NIR) datasets. Some high-performing wavelength selection methods, such as synergy interval partial least squares (siPLS), moving window partial least squares (MW-PLS), competitive adaptive reweighted sampling (CARS), genetic algorithm PLS (GA-PLS) and interval random frog (iRF), were used for comparison. The results show that the proposed method is very promising with good results both on prediction capability and stability. The MATLAB codes for implementing iVISSA are freely available on the website: .

  17. Symbol lock detection implemented with nonoverlapping integration intervals

    NASA Technical Reports Server (NTRS)

    Shihabi, Mazen M. (Inventor); Hinedi, Sami M. (Inventor); Shah, Biren N. (Inventor)

    1995-01-01

    A symbol lock detector is introduced for an incoming coherent digital communication signal which utilizes a subcarrier modulated with binary symbol data, d(sub k), and known symbol interval T by integrating binary values of the signal over nonoverlapping first and second intervals selected to be T/2, delaying the first integral an interval T/2, and either summing or multiplying the second integral with the first one that preceded it to form a value X(sub k). That value is then averaged over a number M of symbol intervals to produce a static value Y. A symbol lock decision can then be made when the static value Y exceeds a threshold level delta.

  18. Experimental uncertainty estimation and statistics for data having interval uncertainty.

    SciTech Connect

    Kreinovich, Vladik (Applied Biomathematics, Setauket, New York); Oberkampf, William Louis (Applied Biomathematics, Setauket, New York); Ginzburg, Lev (Applied Biomathematics, Setauket, New York); Ferson, Scott (Applied Biomathematics, Setauket, New York); Hajagos, Janos (Applied Biomathematics, Setauket, New York)

    2007-05-01

    This report addresses the characterization of measurements that include epistemic uncertainties in the form of intervals. It reviews the application of basic descriptive statistics to data sets which contain intervals rather than exclusively point estimates. It describes algorithms to compute various means, the median and other percentiles, variance, interquartile range, moments, confidence limits, and other important statistics and summarizes the computability of these statistics as a function of sample size and characteristics of the intervals in the data (degree of overlap, size and regularity of widths, etc.). It also reviews the prospects for analyzing such data sets with the methods of inferential statistics such as outlier detection and regressions. The report explores the tradeoff between measurement precision and sample size in statistical results that are sensitive to both. It also argues that an approach based on interval statistics could be a reasonable alternative to current standard methods for evaluating, expressing and propagating measurement uncertainties.

  19. Determination method for aero-engine optimal operation performance interval

    NASA Astrophysics Data System (ADS)

    Fu, Xuyun; Zhang, Guangyao; Tian, Yapeng; Zhong, Shisheng

    2017-08-01

    Considering total cost with the aim to minimize operation cost and maintenance cost in unit time, an aero-engine optimal operation performance interval determination model is proposed in this paper. Compared with previous researches, this model is more reasonable, because the model takes into consideration both operation cost and maintenance cost. The lower limit of the optimal operation performance interval corresponds to maintenance occasion, and the upper limit corresponds to performance restoration degree. Taking an aero-engine as an example, the performance degradation, the operation cost and the maintenance cost are studied and the optimal operation performance interval is solved based on the proposed model. The results show that the proposed model can be applied to solving the aero-engine optimal operation performance interval and determining aero-engine maintenance occasion and maintenance scope.

  20. Concept of Operations for Interval Management Arrivals and Approach

    NASA Technical Reports Server (NTRS)

    Hicok, Daniel S.; Barmore, Bryan E.

    2016-01-01

    This paper presents the concept of operations for interval management operations to be deployed in the US National Airspace System (NAS) by the Federal Aviation Administration (FAA) Interval Management Program. The arrivals and approach operations are explored in detail including the primary operation and variations. The use of interval management operations is described that begin in en route airspace and continue to a termination point inside the arrival terminal area in the highly automated terminal environment that includes other arrival management tools such as arrival metering, Ground-based Interval Management - Spacing (GIM-S), and Terminal Sequencing and Spacing (TSAS). The roles of Air Traffic and Pilots and the ground automation tools that are used by Air Traffic Controllers to enable the operations are explored.

  1. Symbol interval optimization for molecular communication with drift.

    PubMed

    Kim, Na-Rae; Eckford, Andrew W; Chae, Chan-Byoung

    2014-09-01

    In this paper, we propose a symbol interval optimization algorithm in molecular communication with drift. Proper symbol intervals are important in practical communication systems since information needs to be sent as fast as possible with low error rates. There is a trade-off, however, between symbol intervals and inter-symbol interference (ISI) from Brownian motion. Thus, we find proper symbol interval values considering the ISI inside two kinds of blood vessels, and also suggest no ISI system for strong drift models. Finally, an isomer-based molecule shift keying (IMoSK) is applied to calculate achievable data transmission rates (achievable rates, hereafter). Normalized achievable rates are also obtained and compared in one-symbol ISI and no ISI systems.

  2. Confidence Interval for Parameter n in a Binomial Distribution.

    DTIC Science & Technology

    1987-01-01

    procedure of estimating n in the form of a confidence interval . The last section consists of some concluding remark. A simulation procedure, an interactive computer program, and selected tables are included in the appendixes.

  3. Weibull distribution based on maximum likelihood with interval inspection data

    NASA Technical Reports Server (NTRS)

    Rheinfurth, M. H.

    1985-01-01

    The two Weibull parameters based upon the method of maximum likelihood are determined. The test data used were failures observed at inspection intervals. The application was the reliability analysis of the SSME oxidizer turbine blades.

  4. The 32nd CDC: System identification using interval dynamic models

    NASA Technical Reports Server (NTRS)

    Keel, L. H.; Lew, J. S.; Bhattacharyya, S. P.

    1992-01-01

    Motivated by the recent explosive development of results in the area of parametric robust control, a new technique to identify a family of uncertain systems is identified. The new technique takes the frequency domain input and output data obtained from experimental test signals and produces an 'interval transfer function' that contains the complete frequency domain behavior with respect to the test signals. This interval transfer function is one of the key concepts in the parametric robust control approach and identification with such an interval model allows one to predict the worst case performance and stability margins using recent results on interval systems. The algorithm is illustrated by applying it to an 18 bay Mini-Mast truss structure.

  5. Probabilistic robust stabilization of fractional order systems with interval uncertainty.

    PubMed

    Alagoz, Baris Baykant; Yeroglu, Celaleddin; Senol, Bilal; Ates, Abdullah

    2015-07-01

    This study investigates effects of fractional order perturbation on the robust stability of linear time invariant systems with interval uncertainty. For this propose, a probabilistic stability analysis method based on characteristic root region accommodation in the first Riemann sheet is developed for interval systems. Stability probability distribution is calculated with respect to value of fractional order. Thus, we can figure out the fractional order interval, which makes the system robust stable. Moreover, the dependence of robust stability on the fractional order perturbation is analyzed by calculating the order sensitivity of characteristic polynomials. This probabilistic approach is also used to develop a robust stabilization algorithm based on parametric perturbation strategy. We present numerical examples demonstrating utilization of stability probability distribution in robust stabilization problems of interval uncertain systems.

  6. Simulation of Interval Censored Data in Medical and Biological Studies

    NASA Astrophysics Data System (ADS)

    Kiani, Kaveh; Arasan, Jayanthi

    This research looks at the simulation of interval censored data when the survivor function of the survival time is known and attendance probability of the subjects for follow-ups can take any number between 0 to 1. Interval censored data often arise in the medical and biological follow-up studies where the event of interest occurs somewhere between two known times. Regardless of the methods used to analyze these types of data, simulation of interval censored data is an important and challenging step toward model building and prediction of survival time. The simulation itself is rather tedious and very computer intensive due to the interval monitoring of subjects at prescheduled times and subject's incomplete attendance to follow-ups. In this paper the simulated data by the proposed method were assessed using the bias, standard error and root mean square error (RMSE) of the parameter estimates where the survival time T is assumed to follow the Gompertz distribution function.

  7. On computations of variance, covariance and correlation for interval data

    NASA Astrophysics Data System (ADS)

    Kishida, Masako

    2017-02-01

    In many practical situations, the data on which statistical analysis is to be performed is only known with interval uncertainty. Different combinations of values from the interval data usually lead to different values of variance, covariance, and correlation. Hence, it is desirable to compute the endpoints of possible values of these statistics. This problem is, however, NP-hard in general. This paper shows that the problem of computing the endpoints of possible values of these statistics can be rewritten as the problem of computing skewed structured singular values ν, for which there exist feasible (polynomial-time) algorithms that compute reasonably tight bounds in most practical cases. This allows one to find tight intervals of the aforementioned statistics for interval data.

  8. The effects of type of interval, sensory modality, base duration, and psychophysical task on the discrimination of brief time intervals.

    PubMed

    Rammsayer, Thomas H

    2014-05-01

    The present study was designed to investigate the influences of type of psychophysical task (two-alternative forced-choice [2AFC] and reminder tasks), type of interval (filled vs. empty), sensory modality (auditory vs. visual), and base duration (ranging from 100 through 1,000 ms) on performance on duration discrimination. All of these factors were systematically varied in an experiment comprising 192 participants. This approach allowed for obtaining information not only on the general (main) effect of each factor alone, but also on the functional interplay and mutual interactions of some or all of these factors combined. Temporal sensitivity was markedly higher for auditory than for visual intervals, as well as for the reminder relative to the 2AFC task. With regard to base duration, discrimination performance deteriorated with decreasing base durations for intervals below 400 ms, whereas longer intervals were not affected. No indication emerged that overall performance on duration discrimination was influenced by the type of interval, and only two significant interactions were apparent: Base Duration × Type of Interval and Base Duration × Sensory Modality. With filled intervals, the deteriorating effect of base duration was limited to very brief base durations, not exceeding 100 ms, whereas with empty intervals, temporal discriminability was also affected for the 200-ms base duration. Similarly, the performance decrement observed with visual relative to auditory intervals increased with decreasing base durations. These findings suggest that type of task, sensory modality, and base duration represent largely independent sources of variance for performance on duration discrimination that can be accounted for by distinct nontemporal mechanisms.

  9. QT interval and dispersion in primary autonomic failure.

    PubMed Central

    Lo, S. S.; Mathias, C. J.; Sutton, M. S.

    1996-01-01

    OBJECTIVE: To investigate the role of the autonomic nervous system in determining QT interval and dispersion. PATIENTS AND METHODS: 32 patients with chronic primary (idiopathic) autonomic failure (19 men, mean age 60 years) and 21 normal controls (11 men, mean age 59) without symptoms of ischaemic heart disease were studied retrospectively. Autonomic failure was diagnosed by a combination of symptomatic postural hypotension, subnormal plasma noradrenaline response to head-up tilt, and abnormal cardiovascular responses to standing, Valsalva manoeuvre, mental stress, cutaneous cold, isometric exercise, and deep breathing. QT intervals were measured from surface electrocardiograms and QT dispersion was defined as maximum QT--minimum QT occurring in any of the 12 leads. RESULTS: Mean heart rate (RR intervals) was similar in patients with autonomic failure and controls (S2 lead: 865 (132) v 857 (108) ms, P = NS; V2 lead: 865 (130) v 868 (113) ms, P = NS). QT intervals measured from electrocardiogram leads S2 and V2 were significantly longer in patients than in controls (401 (40) v 376 (16) ms, P < 0.01; and 403 (41) v 381 (20) ms, P < 0.05 respectively). The mean maximum QT interval in any lead, which is the best estimate of the maximum duration of electrical systole, was significantly longer in the patients than in controls (417 (48) v 388 (23) ms, P < 0.005). Linear regression analysis of QT and RR intervals for both groups showed a significant difference between the slopes of the two regression lines (F = 8.4, P < 0.001). However, QT dispersions were similar between patients and controls. CONCLUSIONS: Patients with primary autonomic failure have prolongation of QT intervals, indicating that the autonomic nervous system is an important determinant of QT interval. However, QT dispersion does not seem to be affected by chronic primary autonomic denervation. PMID:8665344

  10. Estimating reliable paediatric reference intervals in clinical chemistry and haematology.

    PubMed

    Ridefelt, Peter; Hellberg, Dan; Aldrimer, Mattias; Gustafsson, Jan

    2014-01-01

    Very few high-quality studies on paediatric reference intervals for general clinical chemistry and haematology analytes have been performed. Three recent prospective community-based projects utilising blood samples from healthy children in Sweden, Denmark and Canada have substantially improved the situation. The present review summarises current reference interval studies for common clinical chemistry and haematology analyses. ©2013 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  11. Updating metacognitive control in response to expected retention intervals.

    PubMed

    Fiechter, Joshua L; Benjamin, Aaron S

    2016-10-21

    In five experiments, we investigated whether expected retention intervals affect subjects' encoding strategies. In the first four experiments, our subjects studied paired associates consisting of words from the Graduate Record Exam and a synonym. They were told to expect a test on a word pair after either a short or a longer interval. Subjects were tested on most pairs after the expected retention interval. For some pairs, however, subjects were tested after the other retention interval, allowing for a comparison of performance at a given retention interval conditional upon the expected retention interval. No effect of the expected retention interval was found for 1 min versus 4 min (Exp. 1), 30 s versus 3 min (Exp. 2), and 30 s versus 10 min (Exps. 3 and 4), even when subjects were given complete control over the pacing of study items (Exp. 4). However, when the difference between the expected retention intervals was increased massively (10 min vs. 24 h; Exp. 5), subjects remembered more items that they expected to be tested sooner, an effect consistent with the idea that they traded off efforts to remember items for the later test versus items that were about to be tested. Overall, this set of results accords with much of the test-expectancy literature, revealing that subjects are often reluctant to adjust encoding strategies on an item-by-item basis, and when they do, they usually make quantitative, rather than qualitative, adjustments.

  12. Antipsychotic Polypharmacy and Corrected QT Interval: A Systematic Review.

    PubMed

    Takeuchi, Hiroyoshi; Suzuki, Takefumi; Remington, Gary; Uchida, Hiroyuki

    2015-05-01

    It remains unclear whether antipsychotic polypharmacy, a common clinical practice, is related to an increased risk of corrected time between start of Q wave and end of T wave (QTc) interval prolongation. We conducted a systematic review of the literature to address this important issue. A systematic literature search was conducted in October 2014, using MEDLINE, Embase, and PsycINFO. Studies and case reports were included if they reported QTc intervals or QTc interval changes before and after antipsychotic polypharmacy or QTc intervals in both antipsychotic polypharmacy and monotherapy groups. A total of 21 articles (10 clinical trials, 4 observational studies, and 7 case reports) met inclusion criteria. The clinical trials have shown that a combination treatment with risperidone or pimozide is not obviously related to an increase in QTc interval, whereas ziprasidone or sertindole combined with clozapine may prolong QTc interval. Among the 4 observational studies, antipsychotic polypharmacy was not clearly associated with QTc prolongation in 3 studies, each cross-sectional. In contrast, one prospective study showed a significant increase in QTc interval following antipsychotic coadministration. The case reports indicated an increased risk of QTc prolongation in at least some patients receiving antipsychotic polypharmacy. Currently available evidence fails to confirm that antipsychotic polypharmacy worsens QTc prolongation in general, although the evidence is scarce and inconsistent. Clinicians are advised to remain conservative in resorting to antipsychotic polypharmacy, as a combination of some QTc-prolongation liable antipsychotics may further prolong QTc interval, and efficacy supporting the clinical benefits of antipsychotic polypharmacy is equivocal, at best.

  13. Assessment of Fetal Development Using Cardiac Valve Intervals.

    PubMed

    Marzbanrad, Faezeh; Khandoker, Ahsan H; Kimura, Yoshitaka; Palaniswami, Marimuthu; Clifford, Gari D

    2017-01-01

    An automated method to assess the fetal physiological development is introduced which uses the component intervals between fetal cardiac valve timings and the Q-wave of fetal electrocardiogram (fECG). These intervals were estimated automatically from one-dimensional Doppler Ultrasound and noninvasive fECG. We hypothesize that the fetal growth can be estimated by the cardiac valve intervals. This hypothesis was evaluated by modeling the fetal development using the cardiac intervals and validating against the gold standard gestational age identified by Crown-Rump Length (CRL). Among the intervals, electromechanical delay time, isovolumic contraction time, ventricular filling time and their interactions were selected in a stepwise regression process that used gestational age as the target in a cohort of 57 fetuses. Compared with the gold standard age, the newly proposed regression model resulted in a mean absolute error of 3.8 weeks for all recordings and 2.7 weeks after excluding the low quality recordings. Since Fetal Heart Rate Variability (FHRV) has been proposed in the literature for assessing the fetal development, we compared the performance of gestational age estimation by our new valve-interval based method, vs. FHRV, while assuming the CRL as the gold standard. The valve interval-based method outperformed both the model based on FHRV. Results of evaluation for 30 abnormal cases showed that the new method is less affected by arrhythmias such as tachycardia and bradycardia compared to FHRV, however certain types of heart anomalies cause large errors (more than 10 weeks) with respect to the CRL-based gold standard age. Therefore, discrepancies between the regression based estimation and CRL age estimation could indicate the abnormalities. The cardiac valve intervals have been known to reflect the autonomic function. Therefore the new method potentially provides a novel approach for assessing the development of fetal autonomic nervous system, which may be growth

  14. Assessment of Fetal Development Using Cardiac Valve Intervals

    PubMed Central

    Marzbanrad, Faezeh; Khandoker, Ahsan H.; Kimura, Yoshitaka; Palaniswami, Marimuthu; Clifford, Gari D.

    2017-01-01

    An automated method to assess the fetal physiological development is introduced which uses the component intervals between fetal cardiac valve timings and the Q-wave of fetal electrocardiogram (fECG). These intervals were estimated automatically from one-dimensional Doppler Ultrasound and noninvasive fECG. We hypothesize that the fetal growth can be estimated by the cardiac valve intervals. This hypothesis was evaluated by modeling the fetal development using the cardiac intervals and validating against the gold standard gestational age identified by Crown-Rump Length (CRL). Among the intervals, electromechanical delay time, isovolumic contraction time, ventricular filling time and their interactions were selected in a stepwise regression process that used gestational age as the target in a cohort of 57 fetuses. Compared with the gold standard age, the newly proposed regression model resulted in a mean absolute error of 3.8 weeks for all recordings and 2.7 weeks after excluding the low quality recordings. Since Fetal Heart Rate Variability (FHRV) has been proposed in the literature for assessing the fetal development, we compared the performance of gestational age estimation by our new valve-interval based method, vs. FHRV, while assuming the CRL as the gold standard. The valve interval-based method outperformed both the model based on FHRV. Results of evaluation for 30 abnormal cases showed that the new method is less affected by arrhythmias such as tachycardia and bradycardia compared to FHRV, however certain types of heart anomalies cause large errors (more than 10 weeks) with respect to the CRL-based gold standard age. Therefore, discrepancies between the regression based estimation and CRL age estimation could indicate the abnormalities. The cardiac valve intervals have been known to reflect the autonomic function. Therefore the new method potentially provides a novel approach for assessing the development of fetal autonomic nervous system, which may be growth

  15. Military Applicability of Interval Training for Health and Performance.

    PubMed

    Gibala, Martin J; Gagnon, Patrick J; Nindl, Bradley C

    2015-11-01

    Militaries from around the globe have predominantly used endurance training as their primary mode of aerobic physical conditioning, with historical emphasis placed on the long distance run. In contrast to this traditional exercise approach to training, interval training is characterized by brief, intermittent bouts of intense exercise, separated by periods of lower intensity exercise or rest for recovery. Although hardly a novel concept, research over the past decade has shed new light on the potency of interval training to elicit physiological adaptations in a time-efficient manner. This work has largely focused on the benefits of low-volume interval training, which involves a relatively small total amount of exercise, as compared with the traditional high-volume approach to training historically favored by militaries. Studies that have directly compared interval and moderate-intensity continuous training have shown similar improvements in cardiorespiratory fitness and the capacity for aerobic energy metabolism, despite large differences in total exercise and training time commitment. Interval training can also be applied in a calisthenics manner to improve cardiorespiratory fitness and strength, and this approach could easily be incorporated into a military conditioning environment. Although interval training can elicit physiological changes in men and women, the potential for sex-specific adaptations in the adaptive response to interval training warrants further investigation. Additional work is needed to clarify adaptations occurring over the longer term; however, interval training deserves consideration from a military applicability standpoint as a time-efficient training strategy to enhance soldier health and performance. There is value for military leaders in identifying strategies that reduce the time required for exercise, but nonetheless provide an effective training stimulus.

  16. Reinforcing value of interval and continuous physical activity in children.

    PubMed

    Barkley, Jacob E; Epstein, Leonard H; Roemmich, James N

    2009-08-04

    During play children engage in short bouts of intense activity, much like interval training. This natural preference for interval-type activity may have important implications for prescribing the most motivating type of physical activity, but the motivation of children to be physically active in interval or continuous fashion has not yet been examined. In the present study, ventilatory threshold (VT) and VO2 peak were determined in boys (n=16) and girls (n=16) age 10+/-1.3 years. Children sampled interval and continuous constant-load physical activity protocols on a cycle ergometer at 20% VT on another day. The physical activity protocols were matched for energy expenditure. Children then completed an operant button pressing task using a progressive fixed ratio schedule to assess the relative reinforcing value (RRV) of interval versus continuous physical activity. The number of button presses performed to gain access in interval or continuous physical activity and output maximum (O(max)) were the primary outcome variables. Children performed more button presses (P<0.005) and had a greater O(max) (P<0.005) when working to gain access to interval compared to continuous physical activity at intensities >VT and interval-type physical activity was more reinforcing than continuous constant-load physical activity for children when exercising both >VT and

  17. Scaling and memory in volatility return intervals in financial markets

    NASA Astrophysics Data System (ADS)

    Yamasaki, Kazuko; Muchnik, Lev; Havlin, Shlomo; Bunde, Armin; Stanley, H. Eugene

    2005-06-01

    For both stock and currency markets, we study the return intervals τ between the daily volatilities of the price changes that are above a certain threshold q. We find that the distribution function Pq(τ) scales with the mean return interval [Formula] as [Formula]. The scaling function f(x) is similar in form for all seven stocks and for all seven currency databases analyzed, and f(x) is consistent with a power-law form, f(x) ˜ x-γ with γ ≈ 2. We also quantify how the conditional distribution Pq(τ|τ0) depends on the previous return interval τ0 and find that small (or large) return intervals are more likely to be followed by small (or large) return intervals. This “clustering” of the volatility return intervals is a previously unrecognized phenomenon that we relate to the long-term correlations known to be present in the volatility. Author contributions: S.H. and H.E.S. designed research; K.Y., L.M., S.H., and H.E.S. performed research; A.B. contributed new reagents/analytic tools; A.B. analyzed data; and S.H. wrote the paper.Abbreviations: pdf, probability density function; S&P 500, Standard and Poor's 500 Index; USD, U.S. dollar; JPY, Japanese yen; SEK, Swedish krona.

  18. Procrastination by pigeons with fixed-interval response requirements.

    PubMed Central

    Mazur, J E

    1998-01-01

    Two experiments studied the phenomenon of procrastination, in which pigeons chose a larger, more delayed response requirement over a smaller, more immediate response requirement. The response requirements were fixed-interval schedules that did not lead to an immediate food reinforcer, but that interrupted a 55-s period in which food was delivered at random times. The experiments used an adjusting-delay procedure in which the delay to the start of one fixed-interval requirement was varied over trials to estimate an indifference point--a delay at which the two alternatives were chosen about equally often. Experiment 1 found that as the delay to a shorter fixed-interval requirement was increased, the adjusting delay to a longer fixed-interval requirement also increased, and the rate of increase depended on the duration of the longer fixed-interval requirement. Experiment 2 found a strong preference for a fixed delay of 10 s to the start of a fixed-interval requirement compared to a mixed delay of either 0 or 20 s. The results help to distinguish among different equations that might describe the decreasing effectiveness of a response requirement with increasing delay, and they suggest that delayed reinforcers and delayed response requirements have symmetrical but opposite effects on choice. PMID:9540230

  19. Confidence intervals that match Fisher's exact or Blaker's exact tests

    PubMed Central

    Fay, Michael P.

    2010-01-01

    When analyzing a 2 × 2 table, the two-sided Fisher's exact test and the usual exact confidence interval (CI) for the odds ratio may give conflicting inferences; for example, the test rejects but the associated CI contains an odds ratio of 1. The problem is that the usual exact CI is the inversion of the test that rejects if either of the one-sided Fisher's exact tests rejects at half the nominal significance level. Further, the confidence set that is the inversion of the usual two-sided Fisher's exact test may not be an interval, so following Blaker (2000, Confidence curves and improved exact confidence intervals for discrete distributions. Canadian Journal of Statistics 28, 783–798), we define the “matching” interval as the smallest interval that contains the confidence set. We explore these 2 versions of Fisher's exact test as well as an exact test suggested by Blaker (2000) and provide the R package exact2 ×2 which automatically assigns the appropriate matching interval to each of the 3 exact tests. PMID:19948745

  20. Scaling and memory in volatility return intervals in financial markets

    PubMed Central

    Yamasaki, Kazuko; Muchnik, Lev; Havlin, Shlomo; Bunde, Armin; Stanley, H. Eugene

    2005-01-01

    For both stock and currency markets, we study the return intervals τ between the daily volatilities of the price changes that are above a certain threshold q. We find that the distribution function Pq(τ) scales with the mean return interval \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} \\begin{equation*}{\\bar {{\\tau}}}\\end{equation*}\\end{document} as \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} \\begin{equation*}P_{q}({\\tau})={\\bar {{\\tau}}}^{-1}f({\\tau}/{\\bar {{\\tau}}})\\end{equation*}\\end{document}. The scaling function f(x) is similar in form for all seven stocks and for all seven currency databases analyzed, and f(x) is consistent with a power-law form, f(x) ∼ x-γ with γ ≈ 2. We also quantify how the conditional distribution Pq(τ|τ0) depends on the previous return interval τ0 and find that small (or large) return intervals are more likely to be followed by small (or large) return intervals. This “clustering” of the volatility return intervals is a previously unrecognized phenomenon that we relate to the long-term correlations known to be present in the volatility. PMID:15980152