Sample records for centaurea section acrocentron

  1. Poliploïdia, filogènia i biogeografia en "Centaurea" L. Secció "Acrocentron" ("Cass".) DC

    Font Garcia, Mònica


    [cat] El grup Acrocentron s'ha anat classificant i estructurant de diferents maneres al llarg dels anys, però segons l'última definició del grup estaria format per Centaurea sect. Acrocentron, a més de dues seccions molt petites, Centaurea sect. Chamaecyanus i Centaurea sect. Stephanochilus. Aquest grup es caracteritza cariològicament per ser un grup amb un elevat número d'espècies poliploides.En aquest treball hem intentat establir l'origen de dues sèries poliploides dins d' Acrocentron , ex...

  2. Determination of the relationship between some Centaurea species based on SDS-PAGE

    Uysal, Tuna; Arslan, Emine; Tugay, Osman; ERTUĞRUL, Kuddisi


    The protein patterns of 47 Centaurea species from Turkey were obtained using SDS-PAGE methods. Relationships between Centaurea species and related genera were evaluated via use of a dendrogram. SDS-PAGE provided protein profiles for an important and applicable selection within Centaurea, particularly for the section Cheirolepis and its relatives. We determined that the technique could be used to resolve taxonomic and evolutionary problems in the genus Centaurea, as most of the Centaurea speci...

  3. Sesquiterpene lactones. XXXIII. Guaianolides in the subgenus Psephellus (Cass. Schmalh., genus Centaurea L.

    Gerard Nowak


    Full Text Available Sesquiterpene lactones were found to occur in all of the studied species of the subgenus Psephellus (Cass. Schmalh. Differing compositions were found in the representatives of three sections. In Centaurea declinata MB. from the section Leucophylle (Sosn. Sosn.. 15-deoxyrepin, linichlorin B and cynaropicrin were found. Linichlorin B dominated in Centaurea hypoleucu DC. from section Hypoleucae (Sosn. Sosn., while in the species classified in section Psephellus Sosn., repin, acroptilin, jenerin, centaurepensin and, in some, also cynaropicrin. dominated.

  4. Chemical Constituents of Centaurea cuneifolia

    Aslan, Ümit


    The whole plant material fo Centaurea cuneifolia Sm. afforded three sesquiterpene lactones; cnicin (1), dehydromelitensin (2) and dehydromelitensin-8-[(2'-a-hydroxy-b- hydroxyethyl)-acryloyl)] (3), the lignan; (-)-arctigenin (4), flavonoids; salvigenin (5), eupatilin (6), jaceosidin (7), acacetin (8), kaemferol (9), 5,7,4'-trihydroxy-3-methylether (10), 5-hydroxy-3',',6,7-tetramethoxyflavone (11) and 5-hydroxy-3',4',7,8-tetramet hoxyflavone (12), a trite...




    Centaurea ptosimopappoides was previously investigated by our groupand the presence of two new triterpenes were reported. The rare occurrence ofthis type compounds in the plants prompted us to further investigation of Centaureaptosimopappoides. In this work we report the isolation and structure determinationof an aromatic glycoside which was found in the genus Centaureafor the first time. The structure of the compound was determined by spectralmethods.Key words: Centaurea ptosimopappoides; Co...

  6. Sesquiterpene lactones. XXXI. New guaianolides in Centaurea bella Trautv. and Centaurea adjarica Alb.

    Gerard Nowak


    Full Text Available Nine new guaianolides. I of which are chlorinated, were isolated from the dried, above-ground parts of Centaurea bella Trautv. They are: cebellin A. B, C, D, E. F, G, H and 1. l he known guaianolides centaurepensin and repdiolide were also found. The occurrence of repin. acroptillin and janerin was confirmed. Cebellin F. G. I and repin. acroptillin and janerin were chromatographically shown to occur in Centaurea adjarica Alb.

  7. Cytotoxic Activities of Flavonoids from Centaurea scoparia

    Sayed A. Ahmed; Kamel, Emadeldin M.


    Phytochemical studies on the ethanolic extract of the aerial parts of Centaurea scoparia led to the isolation of two new flavonoids, 3′,4′-dihydroxy-(3′′,4′′-dihydro-3′′-hydroxy-4′′-acetoxy)-2′′,2′′-dimethylpyrano-(5′′,6′′:7,8)-flavone-3-O- β -D-glucopyranoside (1) and 3,3′,4′-trihydroxy-(3′′,4′′-dihydro-3′′,4′′-dihydroxy)-2′′,2′′-dimethylpyrano-(5′′,6′′:7,8)-flavone (2), along with eight known flavonoids isolated for the first time from this plant, cynaroside (3), Apigetrin (4), centaureidin...

  8. Centaurea tchihatcheffii Fischer & C.A. Meyer (Asteraceae)

    Tan, Kit; Vural, Mecit


    Abstract   Centaurea tchihatcheffii is a steppic annual possessing some unique features absent in other Centaureas. The chromosome number is 2n = 20, differing from all other annual species of Centaurea sect. Cyanus. The type locality as published is erroneous and the correct provenance is provided....

  9. Comparative anatomical and ecological investigations on some centaurea (asteracae) taxa from turkey and their taxonomic significance

    The anatomical and ecological characteristics of 7 Centaurea L. s. l. taxa (C. urvillei DC. ssp. stepposa Wagenitz, C. pseudoreflexa Hayek, C. simplicicaulis Boiss. and Huet, C. pecho Albow, C. hypoleuca DC., C. cheiranthifolia Willd.var. purpurascens (DC.) Wagenitz, C. woronowii Bornm.), which three of them are endemic (C. pseudoreflexa, C. pecho, C. woronowii) to Turkey has been carried out. Cross sections of stem, leaf blade and midrib and peripheral sections of the leaves, and pH, total N, P, K and organic matter contents of soil samples have been investigated. Variance analysis and Tukey's Honest Significant Difference test were performed on ecological and anatomical data. Ecological characteristics obtained in this investigation were found mostly similar. On the other hand, anatomically important differences were determined in diversity of anticlinal cell walls, length and width of abaxial epidermis, number of bundles in the midrib and number of stomata per mm/sup 2/ both on the epidermis of the leaf, and the shape of transverse section of stem. According to Tukey's Honest Significant Difference test, especially length and width of abaxial epidermis, number of stomata both on the adaxial and abaxial epidermises have displayed three distinct groups. These results are in accordance with sectional delimitation in the Flora of Turkey and also support upgrading the sum of species of the genus Centaurea. (author)

  10. Chemical constituents of Centaurea omphalotricha Coss. & Durieu ex Batt. & Trab.

    Soumia Mouffok


    Full Text Available The investigation of the aerial parts of Centaurea omphalotricha Coss. & Durieu ex Batt. & Trab. allowed the isolation of nine secondary metabolites corresponding to five flavonoids: oroxylin A (1, chrysin (2, tenaxin II (3, 5,7,2’-trihydroxyflavone (4 and quercetin (5, and four triterpenoids: lupeol (6, taraxasterol (7, daucosterol (8 and β-sitosterol (9. Their structures were established by spectroscopic methods such as 1H and 13C NMR, COSY, HSQC, and HMBC experiments, and ESI-MS, and comparison with literature data. The flavonoids tenaxin II (3 and 5,7,2’-trihydroxyflavone (4 are new for the genus Centaurea L.

  11. Cytotoxic Activities of Flavonoids from Centaurea scoparia

    Sayed A. Ahmed


    Full Text Available Phytochemical studies on the ethanolic extract of the aerial parts of Centaurea scoparia led to the isolation of two new flavonoids, 3′,4′-dihydroxy-(3′′,4′′-dihydro-3′′-hydroxy-4′′-acetoxy-2′′,2′′-dimethylpyrano-(5′′,6′′:7,8-flavone-3-O-β-D-glucopyranoside (1 and 3,3′,4′-trihydroxy-(3′′,4′′-dihydro-3′′,4′′-dihydroxy-2′′,2′′-dimethylpyrano-(5′′,6′′:7,8-flavone (2, along with eight known flavonoids isolated for the first time from this plant, cynaroside (3, Apigetrin (4, centaureidin (5, oroxylin A (6, 5,7-dihydroxy-3′,4′,5′-trimethoxyflavone (7, atalantoflavone (8, 5-hydroxy-3′,4′,8-trimethoxy-2′′,2′′-dimethylpyrano (5′′,6′′:6,7-flavone (9, and 3′,4′,5,8-tetramethoxy-2′′,2′′-dimethylpyrano (5′′,6′′:6,7-flavone (10. The structures of the isolated compounds were elucidated by means of spectroscopic tools including 1D and 2D NMR, UV, IR, and mass spectroscopy. Cytotoxic activities of the isolated compounds were evaluated against human cervical carcinoma HeLa, human hepatocellular carcinoma HepG2, and human breast carcinoma MCF-7. Compound 2 was the most potent cytotoxic agent against HeLa cells with an IC50 0.079 μM.

  12. Chemical constituents of Centaurea omphalotricha Coss. & Durieu ex Batt. & Trab.

    Soumia Mouffok; Hamada Haba; Catherine Lavaud; Christophe Long; Mohammed Benkhaled


    The investigation of the aerial parts of Centaurea omphalotricha Coss. & Durieu ex Batt. & Trab. allowed the isolation of nine secondary metabolites corresponding to five flavonoids: oroxylin A (1), chrysin (2), tenaxin II (3), 5,7,2’-trihydroxyflavone (4) and quercetin (5), and four triterpenoids: lupeol (6), taraxasterol (7), daucosterol (8) and β-sitosterol (9). Their structures were established by spectroscopic methods such as 1H and 13C NMR, COSY, HSQC, and HMBC experiments, and ESI-MS, ...

  13. Brine shrimp lethality bioassay of selected Centaurea L. species (Asteraceae)

    Janaćković P.; Tešević V.; Marin P.D.; Milosavljević S.; Duletić-Laušević Sonja; Janaćković Slavica; Veljić M.


    Ether extracts of 15 Centaurea L. species (Asteraceae) methanol extracts of 12species, and cnicin isolated from C. derventana were tested for general bioactivity using the brine shrimp lethality test. Cnicin showed the most potent activity with LC50 0.2. Also, ether extract of C. splendens showed significant activity with LC50 7.3, as did methanol extract of C. arenaria with LC50 12.4.

  14. Phytotoxic compounds from roots of Centaurea diffusa Lam.

    Quintana, Naira; El Kassis, Elie G; Stermitz, Frank R.; Vivanco, Jorge M.


    An extract of roots of Centaurea diffusa (diffuse knapweed) yielded caryophyllene oxide and linoleic acid which were shown to be phytotoxic. Also isolated were germacrene B, a previously-known phytotoxin as well as the inactive polyene aplotaxene. A combination of these compounds, if transferred to the soil, could be one factor in the invasive behavior of this weed. Contrary to a literature report, 8-hydroxyquinoline was not detected in root exudates of in vitro grown C. diffusa nor could it ...

  15. Bioactivity-guided isolation of antiproliferative compounds from Centaurea arenaria

    Csapi, Bence; Hajdú, Zsuzsanna; Zupko, Istvan; Berényi, Ágnes; Forgo, Peter; Szabó, Pál Tam'S; Hohmann, Judit


    Abstract The antiproliferative effects of n-hexane, chloroform and aqueous methanol extracts prepared from the whole plant of Centaurea arenaria M.B. ex Willd. were investigated against cervix adenocarcinoma (HeLa), breast adenocarcinoma (MCF7) and skin epidermoid carcinoma (A431) cells, using the MTT assay. The chloroform extract displayed high tumour cell proliferation inhibitory activity (higher than 85% at 10 ?g/ml concentration), and was therefore subjected to a bioassay-guide...

  16. Fatty acid composition of six Centaurea species growing in Konya, Turkey.

    Tekeli, Yener; Sezgin, Mehmet; Aktumsek, Abdurrahman; Ozmen Guler, Gokalp; Aydin Sanda, Murad


    In this study, fatty acid compositions of six Centaurea species growing in the Konya region were determined. The fatty acid composition of Centaurea balsamita, Centaurea calolepis, Centaurea carduiformis subsp. carduiformis, Centaurea cariensis subsp. maculiceps, C. cariensis subsp. microlepis and Centaurea iberica were analysed. Four species of these six Centaurea are endemic to Turkey. The endemic Centaurea species are C. calolepis, C. carduiformis subsp. carduiformis, C. cariensis subsp. maculiceps and C. cariensis subsp. microlepis. Generally, C 18:2 ω6 linoleic acid, C 16:0 palmitic acid, C 18:3 ω3 linolenic acid and C 18:1 oleic acid were found to be the major fatty acids in all species. Polyunsaturated fatty acids (PUFAs) were found in higher amounts than saturated fatty acids and monounsaturated fatty acids in all species. PUFAs were determined at 55.10%, 50.25%, 51.41%, 41.02%, 46.18% and 58.80% in C. balsamita, C. calolepis, C. carduiformis subsp. carduiformis, C. cariensis subsp. maculiceps, C. cariensis subsp. microlepis and C. iberica, respectively. PMID:21108113

  17. Bioactividad de los extractos y aislamiento de los lignanos de las semillas de Centaurea dealbata

    Shoeb, M.; Jaspars, M.; Macmanus, S.M.; Thoo-Lin, P.K.; Celik, S; Sarker, S. D.


    La Centaurea dealbata Willd. (familia: Asteraceae) pertenece al g??nero Centaurea, que comprende unas 500 especies. Para evaluar la actividad antioxidante y la toxicidad general de los extractos de n-hexano, diclorometano (DCM) y metanol (MeOH) de las semillas de C. dealbata se han utilizado, respectivamente, el ensayo DPPH y el ensayo de letalidad de gambas en salmuera. Tanto el extracto de DCM como el de MeOH presentaron niveles signifi cativos de actividad antioxidante, con val...

  18. Cytotoxic sesquiterpene lactones and other constituents of Centaurea omphalotricha

    Kolli, El Hadj; Leon, Francisco; Benayache, Samir, E-mail:, E-mail: [Laboratoire de Valorisation des Ressources Naturelles et Synthese de Substances Bioactives, Equipe Associee a l' A.N.D.R.S., Universite Mentouri, Constantine (Algeria); Benayache, Fadila [Laboratoire de Phytochimie et Analyses Physico-Chimiques et Biologiques, Universite Mentouri, Constantine (Algeria); Estevez, Sara; Quintana, Jose; Estevez, Francisco [Departamento de Bioquimica, Unidad Asociada al CSIC, Facultad de Ciencias de la Salud, Universidad de Las Palmas de Gran Canaria (Spain); Instituto Canario de Investigacion del Cancer, Las Palmas de Gran Canaria, Gran Canaria (Spain); Brouard, Ignacio; Bermejo, Jaime [Instituto de Productos Naturales y Agrobiologia, CSIC, La Laguna, Tenerife (Spain)


    Phytochemical research of the aerial parts of Centaurea omphalotricha led to the isolation of three new sesquiterpene lactones, 4'-acetyl cynaropicrin, 4'-acetyl cebellin F and 15-acetyl dehydromelitensin, together with twelve known compounds, seven sesquiterpene lactones, two isoprenoids and three flavonoids. The structures of the new compounds were elucidated by means of extensive 1D and 2D NMR, and MS, and by comparison with reported data in the literature. The effect of sesquiterpene lactones on the viability of the human tumor cell lines HL-60 and U937 was also investigated and 3-acetyl cynaropicrin, and 4'-acetyl cynaropicrin were found to be the most cytotoxic compounds against human leukemia cells with an IC{sub 50} values of 2.0 =- 0.9 and 5.1 +- 0.4 {mu}mol L{sup -1}, respectively. (author)

  19. Revisión taxonómica del complejo Centaurea alba L. (Asteraceae) en la Península Ibérica

    Devesa, J. A.; López, E


    Taxonomic revision of the Centaurea alba L. complex (Asteraceae) in the Iberian Peninsula.- A taxonomic revision of the Centaurea alba L. complex (Centaurea L. sect. Centaurea) in the Iberian Peninsula is presented, which is represented by two species, C. alba and C. costae Willk. Three subspecies of C. alba with reasonably well-defined areas are recognized: C. alba subsp. alba, with three varieties –alba, macrocephala Pau and latronum (Pau) E. López & Devesa-, C. alba subsp. aristifera (Pau...

  20. Effect of Three Centaurea Species Collected from Central Anatolia Region of Turkey on Human Melanoma Cells.

    Russo, Alessandra; Cardile, Venera; Graziano, Adriana C E; Rigano, Daniela; Aktumsek, Abdurrahman; Zengin, Gokhan; Senatore, Felice


    Centaurea is the largest genus within the Asteraceae family. Many members of this genus are used in traditional folk medicine, such as Centaurea pulchella used to treat skin problems such as to resolve the abscess. Although biological activities of many Centaurea species have been investigated in different countries and Turkey, cytotoxic effect of C. patula, C. pulchella and C. tchihatcheffii has not been studied yet. Melanoma is one of the most invasive and deadly forms of skin cancer. Therefore, in an ongoing effort to identify new natural anticancer products for the treatment and/or prevention of melanoma cancer, the present study was undertaken to investigate the effect of these Centaurea species, collected from Central Anatolia region of Turkey on cell growth and death in human melanoma cell line, A375.The results revealed that all extracts were able to inhibit, after 48 h of treatment, the growth of cancer cells, that could be related to an overall action of the phenolic compounds present. In fact, C. pulchella, with the highest level of phenolics, showed a major activity followed by C. patula and C. tchihatcheffii. Our data also demonstrate that these natural products induce apoptotic cell death. In conclusion, the study of plant extracts for their cytotoxic and apoptotic properties has shown that medicinal herbs from Centaurea species might have also importance in the prevention and treatment of melanoma. PMID:27169173


    Raluca DIODIU


    Full Text Available This article is a short review about digital mapping and monitoring of a plant species. The plant species chosen for this purpose was Centaurea ruthenica, a very rare forest steppe species in both Romanian and Europe’s flora, being considered a postglacial relict. The monitoring and the data collected for digital mapping was realized at the Bontida-Jucu site of Centaurea ruthenica. The data obtained after monitoring the species for several years were compared with the already existing data in the literature.

  2. Nectar plant preferences of Hemaris (Sphingidae on co-occurring native Cirsium and non-native Centaurea (Asteraceae inflorescences

    Elena S. Tartaglia


    Full Text Available Preferences for certain nectar plants by moth pollinators have not been extensively studied, particularly seasonal switches in nectar diet. The genus Hemaris, found throughout North America and parts of other continents, is a useful new system to address questions of flower-insect interactions as the moths are relatively common and day-flying. In this study we address the following questions with a group of three Hemaris species. (1 Does Hemaris display a preference for foraging on the native swamp thistle, Cirsium discolor, over the non-native invasive knapweeds, Centaurea spp.? (2 What factors might be driving Hemaris’ preferences? The bloom periods of C. discolor and Centaurea overlap in the northeastern United States, with Centaurea blooming from approximately June through September and C. discolor blooming for approximately the first three weeks of August. Hemaris typically ecloses in the first week of July and fed on Centaurea until C. discolor bloomed. We tracked and recorded Hemaris visits to both plant species. During the co-blooming period of C. discolor and Centaurea, Hemaris visits significantly more C. discolor inflorescences, demonstrating a possible preference for the native species. Hemaris reverts to nectaring at the non-native Centaurea after native C. discolor’s bloom period ends. The nectar of C. discolor has a significantly higher sugar concentration than does the nectar of Centaurea; this difference may account for part of the moths’ preference for C. discolor.

  3. First Report of Crown Gall Caused by Agrobacterium sp. on Diffuse Knapweed (Centaurea diffusa)

    A specimen of diffuse knapweed (Centaurea diffusa, DK) with crown gall-like symptoms was collected July 27, 2004, in Mosier, Wasco Co., OR (N 45.6842, W 121.4021), and sent to the USDA at Ft. Detrick, MD, for identification. A bacterium was isolated on Potato Dextrose Agar that caused hyperplasia a...

  4. Centaurea wagenitziana (Asteraceae: Centaureinae), a new species from the Eastern Balkans

    Tan, Kit; Bancheva, Svetlana; Vural, Mecit; Strid, Arne


    Centaurea wagenitziana Bancheva & Kit Tan from SE Bulgaria and NW Turkey is described as a species new to Bancheva & Kit Tan from SE Bulgaria and NW Turkey is described as a species new to science. Its chromosome number of 2n = 30 is a first report. It closely resembles C. amplifolia with which i...

  5. A new species of Centaurea (Asteraceae) from the island of Samothraki (NE Greece)

    Strid, Arne; Tan, Kit


    Centaurea samothracica (subgen. Acrolophus) is described and illustrated. It is known from a single locality on (subgen. ) is described and illustrated. It is known from a single locality on the North Aegean island of Samothraki, and appears most closely related to C. chalcidicaea from Mt Athos....

  6. Genetic guidelines for the conservation of the endangered polyploid Centaurea borjae (Asteraceae).

    Lopez, Lua; Barreiro, Rodolfo


    Appropriate management of species of conservation concern requires designing strategies that should include genetic information as small population size and restricted geographic range can reduce genetic variation. We used AFLPs to investigate genetic variation within and among populations of the endangered narrow endemic Centaurea borjae, and found no evidence for genetic impoverishment despite its 80 m to maximize genetic variation. PMID:22678690

  7. Assessment of the antioxidant potential and fatty acid composition of four Centaurea L. taxa from Turkey.

    Aktumsek, Abdurrahman; Zengin, Gokhan; Guler, Gokalp Ozmen; Cakmak, Yavuz Selim; Duran, Ahmet


    This paper focused on the assessment of antioxidant property and fatty acid composition of four Centaurea species. The antioxidant activity of its methanol extract was evaluated by several in vitro experiments including phosphomolybedum assay, DPPH assay, β-carotene/linoleic acid, ferric and cupric reducing power. Total phenolic and flavonoid contents were also evaluated. The methanol extract of Centaurea pulcherrima var. pulcherrima showed the superior free radical scavenging activity, linoleic acid inhibition capacity, reducing power and also had the highest total phenolic content. A significant relationship between antioxidant capacity and total phenolic components was found. The oils of Centaurea taxa were also analysed for fatty acid concentration by gas chromatography. The principal fatty acids in the species were palmitic acid (23.38-30.49%) and linoleic acid (20.19-29.93%). These findings suggest that the Centaurea species could be used as a potential source of new natural antioxidants and unsaturated fatty acids in food industry, cosmetics and pharmaceutical preparations. PMID:23768332

  8. Bioactivity of the extracts and isolation of lignans and a sesquiterpene from the aerial parts of Centaurea pamphylica (Asteraceae)

    Shoeb M.; Macmanus S.M.; Kong-Thoo-Lin P.; Celik S.; Jaspars M.; Nahar L.; Sarker S.D


    Centaurea pamphylica Boiss. & Heldr. (Family: Asteraceae), commonly known as ‘pamphylia daisy', is a Turkish endemic species of the genus Centaurea that comprises ca. 500 species, many of which have been used as traditional medicines.  The n-hexane, dichloromethane (DCM) and methanol (MeOH) extracts of the aerial parts of C. pamphylica were assessed for antioxidant activity and general toxicity using, respectively, the 2,2-diphenyl-1-picrylhydrazyl (DPPH), and ...

  9. Components from the Essential oil of Centaurea aeolica Guss. and C. diluta Aiton from Sicily, Italy

    Mariem Ben Jemia


    Full Text Available Volatile components from florets, leaves and stems and branches of Centaurea aeolica Guss. harvested in Lipari, Sicily, Italy, were analysed by gas phase chomatography (GC and gas chomatography mass spectrometry (GC-MS. The main constituents were β-eudesmol, caryophyllene oxide, ( E -12-norcaryophyll-5-en-2-one and hexahydrofarnesylacetone in flowers, hexahydrofarnesylacetone, 2-methyloctadecane and tricosane in the leaves and hexadecanoic acid , caryophyllene oxide and β-eudesmol in the stems and branches . The analysis of the essential oil of the aerial parts of Centaurea diluta Aiton gave mainly fatty acids and derivatives, the main ones being hexadecanoic acid and (Z,Z-9,12-octadecadienoic acid methyl ester.

  10. Constituents of the Egyptian Centaurea scoparia; Part II. Guaianolides of the Aerial Parts.

    Youssef, D; Frahm, A W


    Aerial parts of CENTAUREA SCOPARIA Sieb. afforded a new chlorinated guaianolide with an unusual isobutyl structural feature, diain ( 1), together with three known guaianolides, janerin ( 2), cynaropicrin ( 3), and deacylcynaropicrin ( 4). Structural assignments of the isolated compounds are based on spectroscopic methods including 1D- and 2D-NMR spectroscopy as well as mass spectroscopy. New and revised (1)H- and (13)C-NMR data are reported. PMID:17236083

  11. The case against (-)-catechin involvement in allelopathy of Centaurea stoebe (spotted knapweed)

    Duke, Stephen O; Franck E. Dayan; Bajsa, Joanna; Meepagala, Kumudini M; Hufbauer, Ruth A; Blair, Amy C


    Proving allelopathic chemical interference is a daunting endeavor, in that production and movement of a phytotoxin from a donor plant to a receiving plant must be demonstrated in the substrate in which the plants grow, which is usually a complex soil matrix. The soil levels or soil flux levels of the compound generated by the donor must be proven to be sufficient to adversely affect the receiving plant. Reports of (-)-catechin to be the novel weapon used by Centaurea stoebe (spotted knapweed)...

  12. Sesquiterpene lactones. XXXVI. Sesquiterpene lactones in several subgenera of the genus Centaurea L.

    Gerard Nowak


    Full Text Available The occurrence of both known and new sesquiterpene lactones was determined in six species classified in different subgenera of Centaurea L. Chlorojanerin, cynaropicrin and janerin were isolated from C. phaeopappoides Bordz. and C. thracica (Janka Hayek. C. marschalliana Spreng. was found to contain acroptilin, chlorojanerin, cebellin D and janerin while C. adjarica Alb. had repin, acroptilin, chlorojanerin, centaurepensin, janerin, repidiolide, cebellin D, E, F and L A new, hitherto underscribed cebellin J quaianolide was found in C. bella Trautv. and another germacranolide, 3α, 15-dihydroxycostunolide was found in C. sphaerocephala subsp. lusitanica (Boiss. et Reuter Nyman.

  13. Essential Oil Composition of Centaurea kilaea Boiss. and C. cuneifolia Sm. from Turkey

    POLATO?LU, Kaan; ?EN, Ali; Bulut, Gizem; B?T??, Leyla; GÖREN, Nezhun


    Essential oil composition of Centaurea kilaea flowers, stems and C. cuneifolia flowers were investigated by GC, GC/MS. Flowers and stems of C. kilaea afforded very low essential oil yield <0.01% (v/w). Nineteen and twenty compounds were identified in the flower and stem oils which represent 59.5% and 77.6% of the C. kilaea oil respectively. The main components of the C. kilaea flower oil were hexadecanoic acid 26.2%, tetradecanoic acid 18.1%, ?-Eudesmol 3.3% and decanoic acid 3.1%. The ste...

  14. Sesquiterpene lactones. XXIII. Isolation of sesquiterpene lactones from Centaurea L. species

    Barbara Geppert


    Full Text Available Sesquiterpene lactones were isolated from 18 species or subspecies of the genus Centaurea L.: salonitenolide (I was found in C. crithmifolia Vis., C. friderici Vis., C, paniculata L., C. calcitrapa L., C. pontica Prodan et E. L' Nyarady, C. eriophora L., C. alba L. subsp. deusta (Ten. Nyman, C. alba L. subsp. caliacrae (Prodan Dostal and C. weldeniana Reichenb.; cnicin (II was found in: C. vallesiaca (DC. Jordan, C. calcitrapa L., C. aspera L. subsp. aspera, C. sphaerocephala L. subsp. lusitanica (Boiss. et Reuter Nyman, C. sulphurea Willd., C. eriophora L. and C. rocheliana (Heuffel Dostal; cynaropicrin (III was detected in C. debeauxii Gren. et Gordon subsp. thuillieri Dostal; acroptillin (V, repin (VI and janerin (VII in C. bella Trautv. Other unidentified sesquiterpene lactones were also found to be present in the examined plants.

  15. Ecological, morphological and allozymic differentiation between diploid and tetraploid knapweeds (Centaurea jacea) from a contact zone in the Belgian Ardennes

    Hardy, O J; Vanderhoeven, Sonia; Loose, M.; Meerts, P.


    In the northeastern part of Belgium, the Centaurea jacea complex shows extensive morphological variation and is represented by a diploid (2n = 22) and a tetraploid (2n = 44) cytotype. Polysomic inheritance of allozyme markers in the tetraploids, suggesting autopolyploidy, is here demonstrated for the first time. In order to test whether the tno cytotypes occupy distinct habitats and possess different gene pools, patterns of allozymic and morphological variation were investigated in relation t...

  16. Influence of plant phenostage and ploidy level on oviposition and feeding of two specialist herbivores of spotted knapweed, Centaurea stoebe

    Collins, Alexandra R.; Müller-Schärer, Heinz


    A caged field experiment was used to determine how Centaurea stoebe L. phenostage (rosette, single-stem, multiple-stem) and ploidy level (diploid = 2× and tetraploid = 4×) influence oviposition and feeding of two biological control agents, Agapeta zoegana (Lep.: Cochylidae) and Cyphocleonus achates (Col.: Curculionidae). Ploidy level did not influence oviposition patterns of A. zoegana but rosette and one-stem plants had significantly more eggs than multiple-stem (4×) plants. Differences in o...

  17. Evaluating Antimicrobial Effects of Centaurea Plant’s Essential Oil on Pathogenic Bacteria: Staphylococcus Aureus, Staphylococcus Epidermidis, and Escherichia Coli Isolated from Clinical Specimens

    Haedeh Mobaiyen


    Full Text Available Background & Objectives :Nowadays, development of drug resistance against chemical antimicrobial drugs has attracted attention using medicinal plants in treatment of infections. The aim of this study is to evaluate the antimicrobial effects of two species of Centaurea plant’s essential oil on drug resistant clinical isolates of three pathogenic isolates. Materials & Methods :The studied plants were collected from Marand city in East Azerbaijan, Iran and were confirmed as Centaurea Depressa M.B. and Centaurea Cyanus L. by botanists of Iran Agriculture Organization. The essential oil of these plants (Stems and leaf were extracted via steam distillation method by Clevenger, and their antimicrobial effects were studied by well diffusion method in the abovementioned bacteria. The components of essential oil were identified by injection to gas chromatography linked to mass spectrometry (GC/M. Results :The results of this study prove that the essential oils from the abovementioned plants have bactericidal effects. The most antibacterial effect is observed in Escherichia coli strains. The results of GC/MS chromatography reveal that the essential oils of Centaurea Depressa M.B. and Centaurea Cyanus L. have 28 and 32 compounds, respectively. Conclusion: This study confirmed that the grasses could be used in medicinal plants group with antibacterial properties. However, their effects in vivo must be evaluated and the most effective component of them must be identified carefully so that they can be applied commonly as an alternative synthetic drug in treating infections.

  18. Pollinator interactions with yellow starthistle (Centaurea solstitialis across urban, agricultural, and natural landscapes.

    Misha Leong

    Full Text Available Pollinator-plant relationships are found to be particularly vulnerable to land use change. Yet despite extensive research in agricultural and natural systems, less attention has focused on these interactions in neighboring urban areas and its impact on pollination services. We investigated pollinator-plant interactions in a peri-urban landscape on the outskirts of the San Francisco Bay Area, California, where urban, agricultural, and natural land use types interface. We made standardized observations of floral visitation and measured seed set of yellow starthistle (Centaurea solstitialis, a common grassland invasive, to test the hypotheses that increasing urbanization decreases 1 rates of bee visitation, 2 viable seed set, and 3 the efficiency of pollination (relationship between bee visitation and seed set. We unexpectedly found that bee visitation was highest in urban and agricultural land use contexts, but in contrast, seed set rates in these human-altered landscapes were lower than in natural sites. An explanation for the discrepancy between floral visitation and seed set is that higher plant diversity in urban and agricultural areas, as a result of more introduced species, decreases pollinator efficiency. If these patterns are consistent across other plant species, the novel plant communities created in these managed landscapes and the generalist bee species that are favored by human-altered environments will reduce pollination services.

  19. Bioactivity of the extracts and isolation of lignans and a sesquiterpene from the aerial parts of Centaurea pamphylica (Asteraceae

    Shoeb M.


    Full Text Available Centaurea pamphylica Boiss. & Heldr. (Family: Asteraceae, commonly known as ‘pamphylia daisy', is a Turkish endemic species of the genus Centaurea that comprises ca. 500 species, many of which have been used as traditional medicines.  The n-hexane, dichloromethane (DCM and methanol (MeOH extracts of the aerial parts of C. pamphylica were assessed for antioxidant activity and general toxicity using, respectively, the 2,2-diphenyl-1-picrylhydrazyl (DPPH, and the brine shrimp lethality assays. The reversed-phase preparative HPLC and PTLC were used to isolate compounds from the extracts.  The structures of these compounds [1-4] were elucidated by spectroscopic means, and also by direct comparison with the respective published data.  Both the DCM and the MeOH extract showed significant levels of antioxidant activities with the RC50 values of 72.6 x 10-2 and 47.3 ´ 10-2 mg/mL, respectively. The MeOH extract exhibited low levels of toxicity towards brine shrimps (LD50 = 125.0 ´ 10-2 mg/mL. Three major bioactive components of the MeOH extract were matairesinoside [1], arctiin [2] and matairesinol [3]. An eudesmane-type sesquiterpene, pterodontriol [4], was also isolated from the DCM extract.  Since reactive oxygen species are important contributors to various ailments, the antioxidant properties of the extracts as well as the isolated compounds may be of medicinal significance. This is the first report on the occurrence of 1-4 in C. pamphylica, and 4 in the genus Centaurea.  

  20. New habitats, new menaces: Centaurea x kleinii (C. moncktonii x C. solstitialis, a new hybrid species between two alien weeds

    Susanna, A.


    Full Text Available Anthropic alteration of habitat opens the door to the cohabitation of imported species that in their native range would never coexist. Centaurea solstitialis and Centaurea moncktonii are two invasive species whose natural distributions in Eurasia do not overlap. After introduction in North America, invasive spread led to overlapping distributions. Although the environmental requirements differ between the two species, the close proximity of diverse habitats (within pollinator range has resulted in several cases of natural hybridization between the two. The result of the cross between these two distantly related species is a sterile perennial. Many of its characteristics are intermediate between its parents, but morphologically it is closer to Centaurea moncktonii (probably the maternal parent, and itself of hybrid origin. The plant could possibly become an invasive weed through clonal reproduction. The apparent maternal parent, which the hybrid may more closely resemble physiologically as well as morphologically, is a wellknown creeping weed in alpine pastures throughout Europe.La alteración antrópica del hábitat da paso a la cohabitación de especies importadas que nunca coexistirían en su ámbito natural. Centaurea solstitialis y Centaurea moncktonii son dos especies invasoras cuyas distribuciones en Eurasia apenas se solapan. Después de su introducción en Norteamérica, la expansión invasiva condujo a distribuciones superpuestas. Aunque los requerimientos ambientales de las dos especies son distintos, la proximidad de hábitats diversos (dentro del alcance de los polinizadores ha dado lugar a varios casos de hibridación natural entre ambas. El cruce resultante entre dos especies lejanamente emparentadas es una planta perenne estéril. Muchos de los caracteres del híbrido son intermedios entre sus especies parentales, pero morfológicamente es más parecida a Centaurea moncktonii (probablemente la especie materna y a su vez ya de

  1. Bioactivity of two Turkish endemic Centaurea species, and their major constituents Bioatividade e os principais constituintes químicos de duas espécies de Centaurea, endêmicas da Turquia

    Mohammad Shoeb


    Full Text Available The antioxidant activity, general toxicity and cytotoxicity of the methanol extracts of Centaurea urvillei subs. armata and C. mucronifera have been assessed, respectively, by the DPPH assay, the brine shrimp lethality and the MTT cytotoxicity assays. The reversed-phase HPLC analysis of the methanol extracts afforded two bioactive dibenzylbutyrolactone-type lignans, matairesinoside (1 and arctiin (2. The structures of these lignans were elucidated by comprehensive spectroscopic analyses as well as by the direct comparison of experimental data with respective literature data.A atividade antioxidante, a toxicidade geral e a citotoxidade dos extratos metanólicos de Centaurea urvillei subs. armata e C. mucronifera foram analisados, respectivamente, pelo ensaio DPPH e pelos ensaios de letalidade de Artemia salina e de citotoxidade MTT. A análise dos extratos metanólicos em CLAE de fase reversa apresentou duas lignanas biotivas do tipo dibenzilbutirolactona, matairesinosídeo (1 e arctiina (2. As estruturas destas lignanas foram elucidadas através de análises espectroscópicas completas bem como por comparação direta dos dados experimentais com os respectivos dados da literatura.

  2. On the distribution of Cerastium smolikanum (Caryophyllaceae) and Centaurea vlachorum (Asteraceae) in the Balkan Peninsula

    Shuka, Lulezim; Tan, Kit


    Cerastium smolikanum (Caryophyllaceae) and Centaurea vlachorum (Asteraceae) are reported for the first () and () are reported for the first time in C and NE Albania. These two taxa were previously considered serpentine endemics restricted to a few localities in NW Greece and the extension to their...

  3. Comparing susceptibility of eastern and western U.S. grasslands to competition and allelopathy from spotted knapweed (Centaurea stoebe L. subsp. micranthos (Gugler) Hayek)

    Centaurea maculosa is native to Eurasia and is invasive in the western portion of the US. Negative impacts of C. maculosa present in the eastern US have not been recorded. In this study, we examine the effects of C. maculosa on species diversity on an eastern grassy bald, compare the competitive a...

  4. Polyploidy in phenotypic space and invastion context: A morphometric study of Centaurea stoebe s.l

    Mráz, Patrik; Bourchier, Robert S.; Treier, Urs;


    The taxonomy of the Centaurea stoebe complex is controversial. Diploid and tetraploid plants occur in its native European range, but to date only tetraploids have been recorded from its introduced range in North America. We examined morphological differentiation of C. stoebe using multivariate and...... univariate approaches to clarify the taxonomic status of the known cytotypes. We measured more than 40 morphological traits on plants originating from 78 populations, grown from seed under uniform glasshouse conditions. The ploidy of almost 300 plants from 2 native and 20 introduced populations from Canada...... and 4x plants and thus supported recognition of both cytotypes as separate taxa. Differences in the life cycle, the number of florets, the shape of capitula, and the shape of young rosette leaves were the best discriminant characters. Only minor differences were found between native and introduced...

  5. Evaluating Antimicrobial Effects of Centaurea Plant’s Essential Oil on Pathogenic Bacteria: Staphylococcus Aureus, Staphylococcus Epidermidis, and Escherichia Coli Isolated from Clinical Specimens

    Haedeh Mobaiyen; Abolfazl Jafari Sales; Javad Sayyahi


    Background & Objectives :Nowadays, development of drug resistance against chemical antimicrobial drugs has attracted attention using medicinal plants in treatment of infections. The aim of this study is to evaluate the antimicrobial effects of two species of Centaurea plant’s essential oil on drug resistant clinical isolates of three pathogenic isolates. Materials & Methods :The studied plants were collected from Marand city in East Azerbaijan, Iran and were confirmed ...

  6. Factors affecting in vitro plant regeneration of the critically endangered Mediterranean knapweed ( Centaurea tchihatcheffii Fisch et. Mey)

    Ozel, Cigdem Alev; Khawar, Khalid Mahmood; Mirici, Semra; Ozcan, Sebahattin; Arslan, Orhan


    Habitat destruction has resulted in the extinction of many plant species from the earth, and many more face extinction. Likely, the annual endemic Mediterranean knapweed ( Centaurea tchihatcheffii) growing in the Golbasi district of Ankara, Turkey is facing extinction and needs urgent conservation. Plant tissue culture, a potentially useful technique for ex situ multiplication, was used for the restoration of this ill-fated plant through seed germination, micropropagation from stem nodes, and adventitious shoot regeneration from immature zygotic embryos. The seeds were highly dormant and very difficult to germinate. No results were obtained from the micropropagation of stem nodes. However, immature zygotic embryos showed the highest adventitious shoot regeneration on Murashige and Skoog (MS) medium, containing 1 mg l-1 kinetin and 0.25 mg l-1 NAA. Regenerated shoots were best rooted on MS medium containing 1 mg l-1 IBA and transferred to the greenhouse for flowering and seed set. As such, the present work is the first record of in vitro propagation of critically endangered C. tchihatcheffii, using immature zygotic embryos, and is a step forward towards conservation of this indigenous species.

  7. Floral markers of cornflower (Centaurea cyanus) honey and its peroxide antibacterial activity for an alternative treatment of digital dermatitis.

    Oelschlaegel, Stefanie; Pieper, Laura; Staufenbiel, Rudolf; Gruner, Margit; Zeippert, Linda; Pieper, Bernd; Koelling-Speer, Isabelle; Speer, Karl


    Cornflower (Centaurea cyanus) honey can be characterized by a greenish yellow color and an intense flavor with a bitter aftertaste. Because cornflower honey contains only a limited amount of pollen for the verification of its floral origin, one objective was the characterization of its polyphenol and norisoprenoid contents to assign floral markers. Here, lumichrome (18.8-43.5 mg/kg), 7-carboxylumichrome, (Z/E)-3-oxo-retro-α-ionol, and 3-oxo-α-ionol appeared to be quite suitable for distinguishing cornflower honey from other unifloral honeys. Additionally, due to its comparably high hydrogen peroxide content (0.5-0.9 mM/h) and the associated antibacterial activity, cornflower honey was used as an alternative treatment of digital dermatitis on an organic dairy farm. Cows affected by this hoof disease often show severe lameness and a subsequent decline in milk yield and loss of body condition. The cows' hooves treated with cornflower honey showed significantly faster healing than the control group without any treatment. PMID:23140532




    对矢车菊和大花金鸡菊的染色体进行了研究,结果显示,矢车菊(Centaurea cyanus L.)染色体数目为2n=48,核型公式为K(2n)=4x=48=20m+28sm,相对长度组成为2n=48=4 L+24M2+12 M1+8 S,核型为“2A”;大花金鸡菊(Coreopsis,grandiflora Hogg.)的染色体数目为2n=26,核型公式为K(2n)=2X=26=26m,相对长度组成为2n=26=14M2+10M1+2S,核型为“1A”.%The results of some karyotype studies of Centaurea cyanus L. and Coreopsis grandi-flora Hogg. from Shandong are reported. The results showed: the chromosome number of Centaurea cyanus L. is 2 n = 48, its karyotype formula is K (2 n ) = 4X = 48 = 20 m + 28 sm, composition of rela-tive length of chromosome is 2n =48=4 L + 24 M2 + 12 M1 + 8 S,belonging to “2A” of Stebbins;the chromosome number of Coreopsis grandiflor Hogg. is 2n = 26,its karyotype formula is K (2n) = 2x=26 =26 m, composition of relative length of chromosome is 2n = 26 = 14 M2 + 10 M1 + 2 S,belonging to ”1A”of Stebbins.

  9. Patterns of chloroplast DNA polymorphism in the endangered polyploid Centaurea borjae (Asteraceae): Implications for preserving genetic diversity

    Lua LOPEZ; Rodolfo BARREIRO


    A previous study with amplified fragment length polymorphism (AFLP) fingerprints found no evidence of genetic impoverishment in the endangered Centaurea borjae and recommended that four management units (MUs) should be designated.Nevertheless,the high ploidy (6x) of this narrow endemic plant suggested that these conclusions should be validated by independent evidence derived from non-nuclear markers.Here,the variable trnT-F region of the plastid genome was sequenced to obtain this new evidence and to provide an historical background for the current genetic structure.Plastid sequences revealed little genetic variation; calling into question the previous conclusion that C.borjae does not undergo genetic impoverishment.By contrast,the conclusion that gene flow must be low was reinforced by the strong genetic differentiation detected among populations using plastid sequences (global FST =0.419).The spatial arrangement of haplotypes and diversity indicate that the populations currently located at the center of the species range are probable sites of long-persistence whereas the remaining sites may have derived from a latter colonization.From a conservation perspective,four populations contributed most to the allelic richness of the plastid genome of the species and should be given priority.Combined with previous AFLP results,these new data recommended that five,instead of four,MUs should be established.Altogether,our study highlights the benefits of combining markers with different modes of inheritance to design accurate conservation guidelines and to obtain clues on the evolutionary processes behind the present-day genetic structures.

  10. Species-specific effects of polyploidisation and plant traits of Centaurea maculosa and Senecio inaequidens on rhizosphere microorganisms.

    Thébault, Aurélie; Frey, Beat; Mitchell, Edward A D; Buttler, Alexandre


    Invasive plant species represent a threat to terrestrial ecosystems, but their effects on the soil biota and the mechanisms involved are not yet well understood. Many invasive species have undergone polyploidisation, leading to the coexistence of various cytotypes in the native range, whereas, in most cases, only one cytotype is present in the introduced range. Since genetic variation within a species can modify soil rhizosphere communities, we studied the effects of different cytotypes and ranges (native diploid, native tetraploid and introduced tetraploid) of Centaurea maculosa and Senecio inaequidens on microbial biomass carbon, rhizosphere total DNA content and bacterial communities of a standard soil in relation to plant functional traits. There was no overall significant difference in microbial biomass between cytotypes. The variation of rhizosphere total DNA content and bacterial community structure according to cytotype was species specific. The rhizosphere DNA content of S. inaequidens decreased with polyploidisation in the native range but did not vary for C. maculosa. In contrast, the bacterial community structure of C. maculosa was affected by polyploidisation and its diversity increased, whereas there was no significant change for S. inaequidens. Traits of S. inaequidens were correlated to the rhizosphere biota. Bacterial diversity and total DNA content were positively correlated with resource allocation to belowground growth and late flowering, whereas microbial biomass carbon was negatively correlated to investment in reproduction. There were no correlations between traits of the cytotypes of C. maculosa and corresponding rhizosphere soil biota. This study shows that polyploidisation may affect rhizosphere bacterial community composition, but that effects vary among plant species. Such changes may contribute to the success of invasive polyploid genotypes in the introduced range. PMID:20229242

  11. A rare case of a natural contact zone in Morocco between an autopolyploid and an allopolyploid of Centaurea aspera with sterile tetraploid hybrids.

    Garmendia, A; Ferriol, M; Juarez, J; Zając, A; Kałużny, K; Merle, H


    A new contact zone between Centaurea aspera and Centaurea seridis was found in Morocco. Chromosome counts and flow cytometry showed that both taxa were tetraploid (4x = 44). A literature review and morphometric analysis established that C. aspera corresponds to the autopolyploid C. aspera subsp. gentilii and C. seridis corresponds to the allopolyploid C. seridis var. auriculata. This contact area was compared with the homologous contact zones in Spain formed by the diploid C. aspera subsp. stenophylla and the tetraploid C. seridis subsp. maritima. Natural hybrids between parental species were frequent in both areas. In Spain, hybrids were triploid (from reduced gametes A and gamete AB), highly sterile and exerted a 'triploid block'. In Morocco, cytometry showed that hybrids were tetraploid and, therefore, probably fertile, but all the capitula lacked achenes. It is likely that the resulting genome of the new tetraploid hybrid (AAAB), through the fusion of reduced gametes AA (from subsp. gentilii) and AB (from var. auriculata), could explain irregularities in meiosis through formation of aneuploid gametes and, therefore, infertility of the hybrid. Moroccan sterile tetraploid hybrids develop, but have the identical irregularities to Spanish triploids, probably due to the odd number of homologous chromosomes. The new hybrid is first described as C. x subdecurrens nothosubsp. paucispinus. In addition, distribution and ecological traits are analysed. PMID:25363815


    TEKELİ, Yener


    antioksidan aktivitesinin belirlenmesi amaçlanmıştır. Centaurea Pterocaula 'u yağından uzaklaştırılmak için sokslet apareyi ile petrol eterinde ekstrakte edildi. Sonra materyal %70 lik metanolde tekrar ekstraksiyona tabi tutuldu ve çözücüsünden uzaklaştırıldı. Toplam fenolik madde konsantrasyonu Folin-Ciocalteu metoduna, serbest radikal süpürme etkisi DPPH metoduna göre ve indirgeme gücü ise Oyaizu metoduna göre yapıldı. Bitkinin fenolik yapısı HPLC ile belirlendi. Sonuçlar sen...


    TEKELİ, Yener


    Özet: Bu çalışmada Konya civarından toplanan Centaurea Carduiformis DC. subsp. 'u yağından uzaklaştırılmak için sokslet apareyi ile petrol eterinde ekstrakte edildi. Sonra materyal %70 lik metanolde tekrar ekstraksiyona tabi tutuldu ve çözücüsünden uzaklaştırılarak liyofilize edildi. Antioksidan aktivitesi ölçülene kadar +4 oC de karanlıkta muhafaza edildi. Toplam fenolik madde konsantrasyonu gallik asit standardına göre Folin-Ciocalteu metoduna, serbest radikal süpürme etkisi DPPH (1,1-difen...

  14. Cesarean Sections

    ... arise with the mother and/or baby during pregnancy or labor. An emergency C-section might be required if: labor stops ... of possible problems with the placenta during future pregnancies. In the case of emergency C-sections, the benefits usually far outweigh the ...

  15. FEMA DFIRM Cross Sections

    Minnesota Department of Natural Resources — FEMA Cross Sections are required for any Digital Flood Insurance Rate Map database where cross sections are shown on the Flood Insurance Rate Map (FIRM). Normally...

  16. Cesarean Section Birth

    Full Text Available ... c-section delivery without labor, there's an increased risk for the baby to need some extra help. ... with each successive c-section, there's an increased risk of there being scar tissue, which may increase ...

  17. Cesarean Section Birth

    Full Text Available ... classical cesarean sections, because the risk of uterine rupture with subsequent labor is greater, we generally don' ... With a BVAC, there's a risk of uterine rupture. With multiple cesarean sections, there's a risk of ...

  18. Cesarean Section Birth

    Full Text Available ... JODI JACKSON, MD: Anytime that you have a c-section delivery without labor, there's an increased risk ... important to think about the reasons why a c-section is indicated. The literature suggests that once ...

  19. Cesarean Section Birth

    Full Text Available ... opinion on this seemingly growing trend to undergo electric cesarean section instead of traditional vaginal delivery, especially ... that we've got a completely dry operative field. And it looks really great. So we sort ...

  20. Flow Cytometry Section

    Federal Laboratory Consortium — The primary goal of the Flow Cytometry Section is to provide the services of state-of-the-art multi-parameter cellular analysis and cell sorting for researchers and...

  1. Light Imaging Section

    Federal Laboratory Consortium — The mission of the Light Imaging Section is to give NIAMS scientists access to state-of-the-art light imaging equipment and to offer training and assistance at all...

  2. Cesarean Section Birth

    Full Text Available ... for granted and feel that this is not something that's potentially dangerous, and therefore, maybe we might ... be with the family as much, so it's something to consider always when performing a c-section ...

  3. Cesarean Section Birth

    Full Text Available ... sections sometimes have a good bit of scar tissue. Sometimes there's really not a whole lot there. ... there's an increased risk of there being scar tissue, which may increase the patient's risk for complications ...

  4. Cesarean Section: The Operation

    Full Text Available ... Just a moment, please. You've saved this page It's been added to your dashboard . Cesarean section: ... Map Premature birth report card Careers Archives Health Topics Pregnancy Before or between pregnancies Nutrition, weight & fitness ...

  5. Cesarean Section Birth

    Full Text Available ... you will experience the miracle of birth during a live Internet broadcast from Shawnee Mission Medical Center ... hour, operating surgeon Dr. Leah Ridgway will perform a caesarean section delivery while Dr. Reagan Wittek will ...

  6. Cesarean Section: The Operation

    Full Text Available ... Your e-mail was sent. Save to my dashboard Sign in or Sign up to save this ... saved this page It's been added to your dashboard . Cesarean section: The operation 3:12 Dr. Siobhan ...

  7. Cesarean Section Birth

    Full Text Available ... may increase the patient's risk for complications or injury to surrounding organs such as bowel or bladder. ... sections, there's a risk of scar tissue and injury to surrounding organs. So I think it's oftentimes ...

  8. Cesarean Section Birth

    Full Text Available ... hear the baby and the baby will be right here with her immediately after delivery. So we' ... a repeat cesarean section, we make the incision right through the patient's previous incision. This is called ...

  9. Cesarean Section Birth

    Full Text Available ... We've already started, so things are going well. 00:05:37 FEMALE VOICE: [Unintelligible.] 00:05: ... D. RIDGWAY, MD: Sure. The repeat cesarean section. Well, typically we try not to do elective deliveries ...

  10. Cesarean Section Birth

    Full Text Available ... need a lot of special help. So it's real important when c-sections are performed that we ... patients, the particular risks of both, and both options need to be discussed. And then the patient ...

  11. Utility straight sections

    Leemann, B.; Peggs, S.; Peterson, J.


    Utility straight sections are insertions in the SSC lattice to provide relatively free space to facilitate various beam manipulations. These uses include beam-abort, injection (and conceivably ejection), space for the rf system, and collimation. A typical utility straight section is 1500 meters in overall length (ranging from 500 to 1200 meters). It has zero dispersion and high values of the beta functions. The betatron phase shift across the insertion is about 90{degrees} in each plane.

  12. Dosimetry and Calibration Section

    The two tasks of the Dosimetry and Calibration Section at CERN are the Individual Dosimetry Service which assures the personal monitoring of about 5000 persons potentially exposed to ionizing radiation at CERN, and the Calibration Laboratory which verifies all the instruments and monitors. This equipment is used by the sections of the RP Group for assuring radiation protection around CERN's accelerators, and by the Environmental Section of TISTE. In addition, nearly 250 electronic and 300 quartz fibre dosimeters, employed in operational dosimetry, are calibrated at least once a year. The Individual Dosimetry Service uses an extended database (INDOS) which contains information about all the individual doses ever received at CERN. For most of 1997 it was operated without the support of a database administrator as the technician who had assured this work retired. The Software Support Section of TIS-TE took over the technical responsibility of the database, but in view of the many other tasks of this Section and the lack of personnel, only a few interventions for solving immediate problems were possible

  13. Is (-)-Catechin a "Novel Weapon" of Spotted Knapweed (Centaurea stoebe)?

    The “novel weapons” hypothesis states that some invasive weed species owe part of their success as invaders to allelopathy mediated by allelochemicals that are new to the native species. Presumably, no resistance has evolved among the native species to this new allelochemical (i.e. the novel weapon...

  14. Cesarean Section Birth

    Full Text Available ... cesarean section delivery during this hour-long period. I am Dr. Reagan Wittek. I am an obstetrician with Shawnee Mission Medical Center ... joined us for this webcast. Next to me I have Dr. Elizabeth Wickstrom, who is a maternal- ...

  15. PRES 2012 special section

    Klemeš, Jiří Jaromír; Varbanov, Petar Sabev; Wang, Qiuwang; Lund, Henrik


    This Special Section provides introduction to the 15th Conference Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction (PRES 2012). In this editorial introduction, the editors are highlighting the individual articles included in this issue and discussing the...

  16. Sectional global sensitivity measures

    In this paper the approach of sectional sensitivity measures is introduced. Opposite to well-known global sensitivity measures not only a singleton value is provided to appraise the functional input–output interrelation but rather a more detailed description of these interrelation is enabled. Therefore, the domain of definition (input space) and/or the codomain (result space) are subdivided in a finite number of subdomains/subranges. The evaluation of global sensitivity measures in these subdomains/subranges allows for a proper appraisal of the functional interrelation in local regions. The theoretic background of sectional sensitivity measures is elaborated in detail and exemplified by means of analytical functions. The advantages of sectional sensitivity measures are discussed by means of a medical intervention planning of a radio frequency ablation. - Highlights: • Global sensitivity measures provide just a singleton value per input dimension. • Sectional sensitivity measures enable evaluation of functional interrelation. • Subdivision of input and output in intervals (subdomains). • Usage of absolute partial derivatives as sensitivity measure. • Regional sensitivity statements in input as well as in output space possible

  17. Cesarean Section Birth

    Full Text Available CESAREAN SECTION SHAWNEE MISSION MEDICAL CENTER MERRIAM, KANSAS March 13, 2008 00:00:09 ANNOUNCER: Tonight you will experience the miracle of birth during a live Internet broadcast from Shawnee Mission Medical Center in Merriam, Kansas. Over the next hour, ...

  18. Total Cross Sections

    G. GiacomelliBologna University and INFN


    The measurements of the hadron-hadron total cross sections are the first measurements performed when a new hadron accelerator opens up a new energy region; the measurements were made as function of the incoming beam momentum or c.m. energy and have often been repeated with improved accuracy and finer energy spacing.

  19. Transpacific section planned

    Swift, James


    A transpacific section across the subpolar gyre near latitude 47°N is planned for September-October 1985. This complements the 24.5°N section planned for March-May 1985. The purpose of the expedition is to determine the western boundary current structure, to determine the meridional flow in the region of the Emperor Seamounts, to measure the transport of heat by ocean currents, to determine the net transport of water masses and estimate the meridional general circulation of the north Pacific, and to improve the mapping of tracer distributions in the deep north Pacific.Approximately 110 surface-to-bottom conductivity, temperature, and depth (CTD) rosette stations across the width of the ocean will be occupied, with maximum station spacing of 80 km over abyssal plains, closing to 30-50 km over rough topography and boundaries. Water samples will be collected and analyzed on board for salinity, oxygen, and nutrients.

  20. Pollutant Scavenging Section

    Slinn, W. G.N.; Hales, J. M.; Hane, C. E.; Young, J. A.; Davis, W. E.; Drewes, D. R.; Tanner, T, M.; Thomas, C. W.; Wogman, N. A.; Dana, M. Terry; Glover, D. M.


    This section is comprised of 18 papers. The removal of atmospheric pollutants by clouds and precipitation is a major factor in determining budgets of pollutants distributed on a regional scale. The quantity and patterns of pollutants delivered to sensitive ecosystems, as well as the distributions remaining as inhalation hazards in scavenged air, can only be defined by a thorough investigation of precipitation scavenging processes. Results are reported from research studies on in-cloud scavenging in frontal and convective storms, and below-cloud scavenging of submicron particulates. (CH)

  1. Perimortem caesarean section.

    Parry, Richard; Asmussen, Tilo; Smith, Jason E


    This review describes a simple approach to perimortem caesarean section (PMCS) that can be used by a doctor in the resuscitation room or prehospital environment when faced with a mother of more than 20 weeks gestation in cardiac arrest. It explores the indications for and contraindications to the procedure, the physiological rationale behind it, equipment needed, technical aspects of the procedure and reviews recent literature on maternal and fetal outcomes. Like other uncommon procedures such as emergency department thoracotomy, rehearsal and preparation for a PMCS is essential to give both mother and baby the best chance of survival. PMID:25714106

  2. MedlinePlus: Cesarean Section

    ... C-section C-section - slideshow Cesarean section Going home after a C-section Vaginal birth after C-section Related Health Topics Childbirth Childbirth Problems Languages Arabic (العربية) Bosnian (Bosanski) Chinese - ...

  3. Dosimetry and Calibration Section

    The Dosimetry and Calibration Section fulfils two tasks within CERN's Radiation Protection Group: the Individual Dosimetry Service monitors more than 5000 persons potentially exposed to ionizing radiation on the CERN sites, and the Calibration Laboratory verifies throughout the year, at regular intervals, over 1000 instruments, monitors, and electronic dosimeters used by RP Group. The establishment of a Quality Assurance System for the Individual Dosimetry Service, a requirement of the new Swiss Ordinance for personal dosimetry, put a considerable workload on the section. Together with an external consultant it was decided to identify and then describe the different 'processes' of the routine work performed in the dosimetry service. The resulting Quality Manual was submitted to the Federal Office for Public Health in Bern in autumn. The CERN Individual Dosimetry Service will eventually be officially endorsed after a successful technical test in March 1999. On the technical side, the introduction of an automatic development machine for gamma films was very successful. It processes the dosimetric films without an operator being present, and its built-in regeneration mechanism keeps the concentration of the processing chemicals at a constant level

  4. Environmental Impact Section

    The Section is concerned with preparation of environmental statements and assessments and development of assessment methodologies for energy technologies. During 1976, activities involved nuclear, fossil, and geothermal energy; this work was supported by the U.S.Army, HUD, US ERDA, and US NRC. Two special studies--one on the effects of power plant intake structures on fish impingement and another on multiple uses of cooling lakes--were completed and should serve as references for future analyses. Two research projects sponsored by NRC--the Unified Transport Approach (UTA) to Power Plant Assessment and the Environmental Monitoring Data Evaluation Study--were continued. The purpose of the UA program is to develop fast-transient, one- and two-dimensional transport models for estimating thermal, radiological, chemical, and biological impacts in complicated water bodies. The impact of public use of various products that contain radioactive isotope is being evaluated. The Environmental Impact Sections assistance to NRC expanded to include assessments of fuel-fabrication facilities being considered for relicensing and two uranium in-situ solution mining facility proposals. The work for HUD comprises an assessment of the first application of MIUS in a new town development. A generic environmental statement was prepared and an environmental monitoring program for the facility was designed

  5. Radionuclide transverse section imager

    A radioisotope scanning apparatus for use in nuclear medicine is described in detail. The apparatus enables the quantification and spatial location of the radioactivity in a body section of a patient to be determined with high sensitivity. It consists of an array of highly focussed collimators arranged such that adjacent collimators move in the same circumferential but opposite radial directions. The explicit movements of the gantry are described in detail and may be controlled by a general purpose computer. The use of highly focussed collimators allows both a reasonable solid angle of acceptance and also high target to background images; additionally, dual radionuclide pharmaceutical studies can be performed simultaneously. It is claimed that the high sensitivity of the system permits the early diagnosis of pathological changes and the images obtained show accurately the location and shape of physiological abnormalities. (UK)

  6. Trans-Pacific Section

    A trans-Pacific section along latitude 24.5°N is planned for 1985, with the field program tentatively scheduled for April 17 to June 27. The purpose of the expedition is to measure the transport of heat by ocean currents, to determine the net transport of water masses and estimate the meridional general circulation of the North Pacific, and to improve the mapping of tracer distributions in the deep North Pacific.Approximately 200 surface-to-bottom CTD/rosette stations will be occupied across the width of the ocean, with maximum station spacing of 80 km over abyssal plains, closing to 30-50 km over rough topography and boundaries. Water samples will be collected and analyzed on board for salinity, oxygen, and nutrients.

  7. Radiation and photochemistry section

    The highlights of this past year in the Radiation and Photochemistry Section at Argonne include: (1) picosecond optical studies of radical cations and excited states produced in hydrocarbon radiolysis provided the first kinetic measurements of ion transformation and production of triplet and singlet excited states by ion recombination. (2) studies of radical cations of alkyl-substituted amines and sulfides provided insights into ion-molecule reactions of radical cations in the condensed phase. (3) studies of the behavior of strained alkane radical cations, such as cubane +·, revealed new rearrangements and remarkable, medium-dependent differences in their structures. (4) H·atom reactions yielding eaq- provided the first reliable measurements of hydrated-electron enthalpy and entropy and forced the revision of some previous thinking about the driving force in aq- reactions

  8. Neutrino Cross section Future

    Gollapinni, Sowjanya


    The study of neutrino-nucleus interactions has recently received renewed attention due to their importance in interpreting the neutrino oscillation data. Over the past few years, there has been continuous disagreement between neutrino cross section data and predictions due to lack of accurate nuclear models suitable for modern experiments which use heavier nuclear targets. Also, the current short and long-baseline neutrino oscillation experiments focus in the few GeV region where several distinct neutrino processes come into play resulting in complex nuclear effects. Despite recent efforts, more experimental input is needed to improve nuclear models and reduce neutrino interaction systematics which are currently dominating oscillation searches together with neutrino flux uncertainties. A number of new detector concepts with diverse neutrino beams and nuclear targets are currently being developed to provide necessary inputs required for next generation oscillation experiments. This paper summarizes these effor...

  9. Group cross sections calculations

    Just a few methods have been developped to compute multigroup cross-sections from ENDF data. We have developped an original method in order to get accuracy and to reduce the number of discretization points in the same time; this is why we have tried to use polynomial integration. In this paper, we describe this method: in the first part, we recall some physical hypothesis generally used to solve the linear Boltzmann equation: that is the frame in which the numerical method has been developped. Polynomial methods are really powerfull only if discretization points are suitably chosen. This choice is explained in the next part of this paper. In conclusion, some numerical results are given to illustrate our method

  10. Cancer and Toxicology Section

    The Cancer and Toxicology Section is concerned with the investigation of the mechanisms by which chemicals, radiation, and viruses cause the changes broadly identified as cancer. In addition, the study of mechanisms has been extended to include the nontumorigenic effects of various agents associated with fossil energy and fuels. Research in molecular genetics of carcinogenesis focuses largely on the transposon properties of the genomes of retroviruses. The transposon structure of the DNA genomes of endogenous murine N-tropic and B-tropic type C retroviruses is being elucidated, and their chromosomal location mapped in hamster-mouse cell hybrids. A model of the mechanism of retrovirus induction by radiation and chemicals is being developed, and experiments have established that compounds such as hydroxyurea act as inducer. There is the possibility that transposition of sequences of this endogenous virus may be linked to leukemogenesis. Research in regulation of gene expression aims at defining in molecular terms the mechanisms determining expression of specific genes, how these are regulated by hormones, and the events responsible for dysfunction of gene expression in cancer. In corollary work, a library of cloned cDNAs specific for products of genes of special interest to regulation is being developed. Improvement of reversed-phase chromatography as a means of isolating bacterial plasmids and restriction fragments of DNA is underway. Newly developed techniques permit the isolation of supercoiled plasmid DNA directly from bacterial extracts. The technology has been developed recently for the photosynthetic growth of the chemo-autotrophic organism Rhodospirillum rubrum and the enzyme ribulosebisphosphate carboxylase has been produced in quantity

  11. Industrial Section Convenor's Report

    Barone, M.; Riboni, P.


    recently into the areas of interest of our community (Hourdakis and Intrasoft) and the examples of an Industry historically committed to a strong R&D effort (SAES-Getters). Finally a case of involvement of industry in a "Big Science" project (CMS) completed the palette of the contributions to this Industry Section. The full set of transparencies of the lectures, are filed and made available at the conference site: .

  12. PLSS Townships and Sections, Sections, Published in 2003, Daggett County.

    NSGIC GIS Inventory (aka Ramona) — This PLSS Townships and Sections dataset, was produced all or in part from Other information as of 2003. It is described as 'Sections'. Data by this publisher are...

  13. Diffractive and rising cross sections

    The energy dependence of the diffractive component of the proton-proton cross section is discussed and its contribution to the rise of the total cross section at high energies is examined. 17 refs., 9 figs

  14. C-section - series (image)

    ... anesthesia, which renders the patient unconscious, for emergency C-sections because it can be administered quickly and takes effect almost immediately. When the C-section is planned, the doctor may order regional ...

  15. [Fast neutron cross section measurements

    This paper discusses the following topics: 14 MeV pulsed neutron facility; detection and measurement system; 238U capture cross sections at 23 and 964 keV using photon neutron sources; capture cross sections of Au-197 at 23 and 964 keV; and yttrium nuclear cross section measurement

  16. Scheduling a C-Section

    ... Pregnancy > Labor & birth > Scheduling a c-section Scheduling a c-section E-mail to a friend Please fill in all fields. Please enter ... and develop before she’s born. Why can scheduling a c-section for non-medical reasons be a ...

  17. Modeling golden section in plants

    Lanling Zeng; Guozhao Wang


    Plants are complex structures, changing their shapes in response to environmental factors such as sunlight, water and neighboring plants. However, some mathematical rules can be found in their growth patterns, one of which is the golden section. The golden section can be observed in branching systems, phyllotaxis, flowers and seeds, and often the spiral arrangement of plant organs. In this study, tree, flower and fruit models have been generated by using the corresponding golden section characteristics, resulting in more natural patterns. Furthermore, the golden section can be found in the bifurcate angles of trees and lobed leaves, extending the golden section theory.

  18. Taxonomy of Penicillium section Citrina

    Houbraken, Jos; Frisvad, Jens Christian; Samson, R.A.


    Species of Penicillium section Citrina have a worldwide distribution and occur commonly in soils. The section is here delimited using a combination of phenotypic characters and sequences of the nuclear ribosomal RNA gene operon, including the internal transcribed spacer regions ITS1 and ITS2, the 5...... containing flanged ascospores. In the present study, more than 250 isolates presumably belonging to section Citrina were examined using a combined analysis of phenotypic and physiological characters, extrolite profiles and ITS, β-tubulin and/or calmodulin sequences. Section Citrina includes 39 species, and...

  19. (n,2n) cross sections

    Most of the fission products and a few of the actinides in ENDF/B-V do not have (n,2n) cross sections. A complete set of these cross sections is presented in the multigroup structure defined. These were constructed for future use in the DANDE Code System

  20. XCOM: Photon Cross Sections Database

    SRD 8 XCOM: Photon Cross Sections Database (Web, free access)   A web database is provided which can be used to calculate photon cross sections for scattering, photoelectric absorption and pair production, as well as total attenuation coefficients, for any element, compound or mixture (Z <= 100) at energies from 1 keV to 100 GeV.

  1. Cross Sections and Lorentz Violation

    Colladay, Don; Kostelecky, Alan


    The derivation of cross sections and decay rates in the Lorentz-violating standard-model extension is discussed. General features of the physics are described, and some conceptual and calculational issues are addressed. As an illustrative example, the cross section for the specific process of electron-positron pair annihilation into two photons is obtained.

  2. Three-Section Expiratory CT:

    Loeve, Martine; de Bruijne, Marleen; Hartmann, Ieneke C. J.;


    a cross-sectional and longitudinal study.Materials and Methods: In this institutional review board-approved pilot study, 20 subjects aged 6-20 years (12 female and eight male; median age, 12.6 years) contributed two expiratory CT studies (three-section baseline CT, volumetric follow-up CT) and two...... PFT studies over 2 years after parental informed consent was obtained. From follow-up CT studies, seven sets were composed: Set 1 was volumetric. Sets 2, 3, 4, and 5, had spacing of 2.4, 4.8, 9.6, and 20.4 mm, respectively, between sections. Sets 6 and 7 contained five and three sections, respectively....... Longitudinal follow-up was performed with three sections. All images were deidentified and randomized, and TA was scored with the Brody II system and a new quantitative system. Statistical analysis included the Wilcoxon signed rank test, calculation of Spearman and intraclass correlation coefficients, and use...

  3. Cesarean Section: Recovering After Surgery

    Full Text Available ... Just a moment, please. You've saved this page It's been added to your dashboard . Cesarean section: ... Map Premature birth report card Careers Archives Health Topics Pregnancy Before or between pregnancies Nutrition, weight & fitness ...

  4. Multifamily Assistance Section 8 Contracts

    Department of Housing and Urban Development — he information regarding the Multifamily Assistance and Section 8 contracts, and properties is being furnished for the convenience of interested parties. The...

  5. Cesarean Section: Recovering After Surgery

    Full Text Available ... Your e-mail was sent. Save to my dashboard Sign in or Sign up to save this ... saved this page It's been added to your dashboard . Cesarean section: Recovering after surgery 3:47 Dr. ...

  6. US Forest Service Ecological Sections

    US Forest Service, Department of Agriculture — A map service on the www depicting ecological section boundaries within the conterminous United States. The map service contains regional geographic delineations...

  7. Measurement of fission cross sections

    A review is presented on the recent progress in the experiment of fission cross section measurement, including recent activity in Japan being carried out under the project of nuclear data measurement. (author)

  8. Who's afraid of Section 13?

    This article discusses the time restrictions of Section 13 of the Federal Power Act and its impact on independent hydroelectric plant project development. The topics of the article include Section 13 history, the Government Accounting Office report findings regarding developers 'banking' of proposed project sites and project construction commencement time limits, and a review of Federal Energy Regulatory Commission data on license applications, licenses granted and completed projects

  9. The total charm cross section

    R. Vogt


    We assess the theoretical uncertainties on the total charm cross section. We discuss the importance of the quark mass, the scale choice and the parton densities on the estimate of the uncertainty. We conclude that due to the small charm quark mass, which amplifies the effect of the other parameters in the calculation, the uncertainty on the total charm cross section is difficult to quantify.

  10. Particle sizes from sectional data

    Pawlas, Zbynek; Nyengaard, Jens Randel; Jensen, Eva Bjørn Vedel


    We propose a new statistical method for obtaining information about particle size distributions from sectional data without specific assumptions about particle shape. The method utilizes recent advances in local stereology. We show how to estimate separately from sectional data the variance due to...... the local stereological estimation procedure and the variance due to the variability of particle sizes in the population. Methods for judging the difference between the distribution of estimated particle sizes and the distribution of true particle sizes are also provided....

  11. [Cesarean section and eye disorders].

    Karska-Basta, Izabella; Tarasiewicz, Marta; Kubicka-Trząska, Agnieszka; Miniewicz, Joanna; Romanowska-Dixon, Bożena


    Recently, a growing tendency for cesarean birth has been noted both, in Poland and worldwide. Non-obstetric problems constitute a large part of indications for cesarean section. Many ophthalmologists and obstetricians still believe that high myopia, the presence of peripheral retinal degenerations, history of retinal detachment surgery, diabetic retinopathy, or glaucoma are indications for surgical termination of pregnancy. However, these recommendations are not evidence-based. The literature offers no proof that high myopia and previous retinal surgery increase the risk of retinal detachment during spontaneous vaginal delivery. There is only one indication for cesarean section in myopic patients, i.e. the presence of choroidal neovascularization, which can cause subretinal bleeding with acute visual loss. Prolonged and intensified Valsalva maneuver during labor in patients with an active proliferative diabetic retinopathy may be an indication for an elective cesarean section. Uterine contractions during the second stage of vaginal delivery lead to a marked elevation of intraocular pressure. Intraocular pressure fluctuations during the delivery may damage retinal ganglion cells, resulting in further progression of visual field. Thus, glaucoma associated with advanced visual field changes is the next ophthalmic indication for cesarean section. The report presents the current state of knowledge concerning the effect of pregnancy on pre-existing ocular disorders and the influence of physiological changes on the clinical course of these diseases during the stages of natural delivery. The authors discuss also the ophthalmic indications for cesarean section. PMID:27306132

  12. The Hausdorff Dimension of Sections

    Min NIU; Lifeng XI


    The notion of finite-type open set condition is defined to calculate the Hausdorff dimensions of the sections of some self-similar sets, such as the dimension of intersection of the Koch curve and the line x = a with a ∈(Q).

  13. Revolutionizing Cross-sectional Imaging

    Fan, Yifang; Luo, Liangping; Lin, Wentao; Li, Zhiyu; Zhong, Xin; Shi, Changzheng; Newman, Tony; Zhou, Yi; Lv, Changsheng; Fan, Yuzhou


    Cross-sectional imaging is so important that, six Nobel Prizes have been awarded to the field of nuclear magnetic resonance alone because it revolutionized clinical diagnosis. The BigBrain project supported by up to 1 billion euro each over a time period of 10 years predicts to "revolutionize our ability to understand internal brain organization" (Evan 2013). If we claim that cross-sectional imaging diagnosis is only semi-quantitative, some may believe because no doctor would ever tell their patient that we can observe the changes of this cross-sectional image next time. If we claim that BigBrain will make no difference in clinical medicine, then few would believe because no doctor would ever tell their patient to scan this part of the image and compare it with that from the BigBrain. If we claim that the BigBrain Project and the Human Brain Project have defects in their key method, one might believe it. But this is true. The key lies in the reconstruction of any cross-sectional image along any axis. Using Ga...

  14. Terahertz radar cross section measurements

    Iwaszczuk, Krzysztof; Heiselberg, Henning; Jepsen, Peter Uhd


    We perform angle- and frequency-resolved radar cross section (RCS) measurements on objects at terahertz frequencies. Our RCS measurements are performed on a scale model aircraft of size 5-10 cm in polar and azimuthal configurations, and correspond closely to RCS measurements with conventional radar...

  15. Vibratome sections of difficult tissues

    Zelander, T; Kirkeby, S


    After 1 hours of aldehyde fixation, 4 to 20 hours of soaking in 2% BSA (bovine serum albumin) solution and another 17 hours in the same fixative, the vibratome will produce smooth, even sections from agar embedded guinea pig thyroid, skeletal muscle or larynx with the same ease as it will from soft......, homogeneous tissues such as liver or spleen....

  16. Neonatology and the caesarean section.

    Zanini, R; Minghetti, D


    The origins of the use of the Caesarean section date far back in human history. Traces of this procedure can be found in Greek mythology and in the history of Ancient Rome. Many documents about the history of religion make reference to a delivery from the abdomen. PMID:22958012

  17. Cross sections for nuclear astrophysics

    General properties of low-energy cross sections and of reaction rates are presented. We describe different models used in nuclear astrophysics: microscopic models, the potential model, and the R-matrix method. Two important reactions, 7Be(p,γ)8B and 12C(α,γ)16O, are then briefly discussed. (author)

  18. Metonymy and Cross Section Demand

    Evstigneev, Igor V.; Hildenbrand, Werner; Jerison, Michael


    Cross section consumer expenditure data are frequently used to make conclusions about consumer demand behavior. Such conclusions, however, can only be justified under certain assumptions, which are often left unstated in the empirical demand literature. An assumption of this type, the metonymy hypothesis, was stated rigorously and then exploited by Hardle, Hildenbrand and Jerison when analyzing the monotonicity property of aggregate demand functions. The purpose of the present paper is to exa...

  19. Wind Turbine Radar Cross Section

    David Jenn; Cuong Ton


    The radar cross section (RCS) of a wind turbine is a figure of merit for assessing its effect on the performance of electronic systems. In this paper, the fundamental equations for estimating the wind turbine clutter signal in radar and communication systems are presented. Methods of RCS prediction are summarized, citing their advantages and disadvantages. Bistatic and monostatic RCS patterns for two wind turbine configurations, a horizontal axis three-blade design and a vertical axi...

  20. New activation cross section data

    New nuclear cross section libraries (known as USACT92) have been created for activation calculations. A point-wise file was created from merging the previous version of the activation library, the U.S. Nuclear Data Library (ENDF/B-VI), and the European Activation File (EAF-2). 175 and 99 multi-group versions were also created. All the data are available at the National Energy Research Supercomputer Center

  1. Progress report : Plasma Physics Section

    The activities of the plasma physics section of the Bhabha Atomic Research Centre, India over the last five years (1970-75) are reported. The R and D programme of the section has been divided into four cells mainly i.e., (i) Thermal plasma (ii) Relativistic Electron Beam (iii) Energetics and (iv) Electron beam technology. The salient features of the development activities carried out in these cells are outlined. In the Thermal plasma group, considerable research work has been done in (a) fundamental plasma studies, (b) industrial plasma technology and (c) open cycle MHD power generation project. The relativistic electron beam group is engaged in improving the technology to realize high power lasers, and pulsed thermonuclear fusion. The energetics programme is oriented to develop high voltage d.c. generators and pulse generators. The electron beam techniques developed here are routinely used for melting refractory and reactive metals. The technical know-how of the welding machines developed has been transfered to industries. Equipment developed by this section, such as, (1) electron beam furnace, (2) plasma cutting torch, (3) impulse magnet charger etc. are listed. (A.K.)

  2. Microscopic cross sections: An utopia?

    Hilaire, S. [CEA Bruyeres-le-Chatel, DIF 91 (France); Koning, A.J. [Nuclear Research and Consultancy Group, PO Box 25, 1755 ZG Petten (Netherlands); Goriely, S. [Institut d' Astronomie et d' Astrophysique, Universite Libre de Bruxelles, Campus de la Plaine, CP 226, 1050 Brussels (Belgium)


    The increasing need for cross sections far from the valley of stability poses a challenge for nuclear reaction models. So far, predictions of cross sections have relied on more or less phenomenological approaches, depending on parameters adjusted to available experimental data or deduced from systematical relations. While such predictions are expected to be reliable for nuclei not too far from the experimentally known regions, it is clearly preferable to use more fundamental approaches, based on sound physical bases, when dealing with very exotic nuclei. Thanks to the high computer power available today, all major ingredients required to model a nuclear reaction can now be (and have been) microscopically (or semi-microscopically) determined starting from the information provided by a nucleon-nucleon effective interaction. We have implemented all these microscopic ingredients in the TALYS nuclear reaction code, and we are now almost able to perform fully microscopic cross section calculations. The quality of these ingredients and the impact of using them instead of the usually adopted phenomenological parameters will be discussed. (authors)

  3. X-ray Fluorescence Sectioning

    Cong, Wenxiang


    In this paper, we propose an x-ray fluorescence imaging system for elemental analysis. The key idea is what we call "x-ray fluorescence sectioning". Specifically, a slit collimator in front of an x-ray tube is used to shape x-rays into a fan-beam to illuminate a planar section of an object. Then, relevant elements such as gold nanoparticles on the fan-beam plane are excited to generate x-ray fluorescence signals. One or more 2D spectral detectors are placed to face the fan-beam plane and directly measure x-ray fluorescence data. Detector elements are so collimated that each element only sees a unique area element on the fan-beam plane and records the x-ray fluorescence signal accordingly. The measured 2D x-ray fluorescence data can be refined in reference to the attenuation characteristics of the object and the divergence of the beam for accurate elemental mapping. This x-ray fluorescence sectioning system promises fast fluorescence tomographic imaging without a complex inverse procedure. The design can be ad...

  4. [Fast neutron cross section measurements

    In the 14 MeV Neutron Laboratory, we have continued the development of a facility that is now the only one of its kind in operation in the United States. We have refined the klystron bunching system described in last year's report to the point that 1.2 nanosecond pulses have been directly measured. We have tested the pulse shape discrimination capability of our primary NE 213 neutron detector. We have converted the RF sweeper section of the beamline to a frequency of 1 MHz to replace the function of the high voltage pulser described in last year's report which proved to be difficult to maintain and unreliable in its operation. We have also overcome several other significant experimental difficulties, including a major problem with a vacuum leak in the main accelerator column. We have completed additional testing to prove the remainder of the generation and measurement systems, but overcoming some of these experimental difficulties has delayed the start of actual data taking. We are now in a position to begin our first series of ring geometry elastic scattering measurements, and these will be underway before the end of the current contract year. As part of our longer term planning, we are continuing the conceptual analysis of several schemes to improve the intensity of our current pulsed beam. These include the provision of a duoplasmatron ion source and/or the provision of preacceleration bunching. Additional details are given later in this report. A series of measurements were carried out at the Tandem Dynamatron Facility involving the irradiation of a series of yttrium foils and the determination of activation cross sections using absolute counting techniques. The experimental work has been completed, and final analysis of the cross section data will be completed within several months

  5. [Fast neutron cross section measurements

    In this report, we outline the progress achieved in two distinct under the DOE-sponsored cross section project: the initial results obtained from the pulsed 14 MeV neutron facility, and a cooperative effort with Argonne National Laboratory in the measurement of fast neutron cross sections in yttrium. In the 14 MeV neutron laboratory, this year has seen the maturation of the project into one in which initial scattering measurements are now underway. We have improved the accelerator and ion source in several significant ways, so that neutron intensities have now been proven to be adequate for our series of elastic scattering angular distribution measurements outlined in our initial proposal of two years ago. We have successfully tested all components of the time-of-flight spectrometer and recorded initial neutron spectra from the ring targets that we have obtained for our first angular distribution measurements. Examples of the time-of-flight spectra that have been obtained are given later in this report. At the present time, the accelerator is operating with the highest degree of reliability that we have experienced since installing the pulsing system. Improvements made over the past year have not only increased the available neutron intensity, but also increased our capability to deal with inevitable component failures that require repair or replacement. The measurements carried out in conjunction with Argonne have contributed significantly to the available database on fast neutron interactions in yttrium. Results indicate that the cross section for the 89 Y(n,p)89Sr reaction is substantially higher than represented in ENDF/B-VI

  6. Activities of Radiation Standard Section

    A brief account of the various facilities and services provided by the Radiation Standards Section (RSS) of the Bhabha Atomic Research Centre, Bombay is given. RSS maintains the primary and secondary standards of various parameters of radiation measurements. It ensures accurate radiological measurements as per international requirements, through periodic international intercomparisons of national standards. It also provides calibration services to various users of radiation sources and instruments. The activities of RSS are described under the headings: (1) Radiological Metrology Standards, (2) Radionuclide Standards, Neutron Metrology, (4) Instruments Calibration, (5) Non-ionizing Radiations, and (6) Instrumentation. (author). figs., tabs

  7. Wind Turbine Radar Cross Section

    David Jenn


    Full Text Available The radar cross section (RCS of a wind turbine is a figure of merit for assessing its effect on the performance of electronic systems. In this paper, the fundamental equations for estimating the wind turbine clutter signal in radar and communication systems are presented. Methods of RCS prediction are summarized, citing their advantages and disadvantages. Bistatic and monostatic RCS patterns for two wind turbine configurations, a horizontal axis three-blade design and a vertical axis helical design, are shown. The unique electromagnetic scattering features, the effect of materials, and methods of mitigating wind turbine clutter are also discussed.

  8. Vacuum Chambers for LEP sections


    The picture shows sections of the LEP vacuum chambers to be installed in the dipole magnets (left) and in the quadrupoles (right). The dipole chamber has three channels: the beam chamber, the pumping duct where the NEG (non-evaporabe getter) is installed and the water channel for cooling (on top in the picture). The pumping duct is connected to the beam chamber through holes in the separating wall. The thick lead lining to shield radiation can also be seen. These chambers were manufactured as extruded aluminium alloy profiles.

  9. Nuclear Data Section status report

    This report summarises the Nuclear Structure and Decay Data (NSDD) related activity of the IAEA Nuclear Data Section (NDS) for the period October 1998 to September 2000. It covers both online NSDD user service either Telnet or Web services, and offline NSDD service. The NSDD development programs and projects are related to NDS contribution to the IAEA Analytical Quality Control Services program, Coordinated Research Project on nuclear model parameter testing for nuclear data evaluation, Coordinated Research Project on updating of x-ray and gamma-ray decay data standards for detector calibration, and Coordinated Research Project on development of database for prompt gamma-neutron activation analysis

  10. Turbine airfoil having outboard and inboard sections

    Mazzola, Stefan; Marra, John J


    A turbine airfoil usable in a turbine engine and formed from at least an outboard section and an inboard section such that an inner end of the outboard section is attached to an outer end of the inboard section. The outboard section may be configured to provide a tip having adequate thickness and may extend radially inward from the tip with a generally constant cross-sectional area. The inboard section may be configured with a tapered cross-sectional area to support the outboard section.

  11. Medical Reasons for a C-Section

    ... Labor & birth > Medical reasons for a c-section Medical reasons for a c-section E-mail to ... have your baby through vaginal birth. What are medical reasons for having a c-section? Your health ...

  12. 14 CFR Section 2 - General Accounting Policies


    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false General Accounting Policies Section 2 Section 2 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION... General Accounting Provisions Section 2 General Accounting Policies...

  13. To the Ocean Sciences section

    Hickey, Barbara

    To maximize our ability to obtain recognition of Ocean Sciences Section members as Fellows of AGU while minimizing the associated workload, I have, in consultation with our executive committee, established an Ocean Sciences Fellows Committee chaired by the President-Elect to oversee and assist in the nomination process.The committee asks that anyone wanting to sponsor a nomination send a one-page proposal telling why an individual should be made a Fellow. Proposals will be reviewed by the commitee, and a number equal to 1 ½ to 2 times our nomination quota will be chosen for full presentation. Committee members will then work with nominators to select and contact seconders, while the nominator provides the required curriculum vitae and publication list. The committee will assist in any manner possible to insure that the files that go forward are both timely and well documented.

  14. 24 CFR 882.123 - Conversion of Section 23 Units to Section 8 and Section 23 monitoring.


    ... Housing Annual Adjustment Factor (24 CFR part 888) most recently published by HUD in the Federal Register... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Conversion of Section 23 Units to... Applicability, Scope and Basic Policies § 882.123 Conversion of Section 23 Units to Section 8 and Section...

  15. [Fast neutron cross section measurements

    From its inception, the Nuclear Data Project at the University of Michigan has concentrated on two major objectives: (1) to carry out carefully controlled nuclear measurements of the highest possible reliability in support of the national nuclear data program, and (2) to provide an educational opportunity for students with interests in experimental nuclear science. The project has undergone a successful transition from a primary dependence on our photoneutron laboratory to one in which our current research is entirely based on a unique pulsed 14 MeV fast neutron facility. The new experimental facility is unique in its ability to provide nanosecond bursts of 14 MeV neutrons under conditions that are ''clean'' and as scatter-free as possible, and is the only one of its type currently in operation in the United States. It has been designed and put into operation primarily by graduate students, and has met or exceeded all of its important initial performance goals. We have reached the point of its routine operation, and most of the data are now in hand that will serve as the basis for the first two doctoral dissertations to be written by participating graduate students. Our initial results on double differential neutron cross sections will be presented at the May 1993 Fusion Reactor Technology Workshop. We are pleased to report that, after investing several years in equipment assembly and optimization, the project has now entered its ''data production'' phase

  16. Vaginal birth after cesarean section

    Vidyadhar B Bangal


    Full Text Available Background: The rate of primary cesarean section (CS is on the rise. More and more women report with a history of a previous CS. A trial of vaginal delivery can save these women from the risk of repeat CS. Aims: The study was conducted to assess the safety and success rate of vaginal birth after CS (VBAC in selected cases of one previous lower segment CS (LSCS. Materials and Methods: The prospective observational study was carried out in a tertiary care teaching hospital over a period of two years. One hundred pregnant women with a history of one previous LSCS were enrolled in the study. Results: In the present study, 85% cases had a successful VBAC and 15% underwent a repeat emergency LSCS for failed trial of vaginal delivery. Cervical dilatation of more than 3 cm at the time of admission was a significant factor in favor of a successful VBAC. Birth weight of more than 3,000 g was associated with a lower success rate of VBAC. The incidence of scar dehiscence was 2% in the present study. There was no maternal or neonatal mortality. Conclusion: Trial of VBAC in selected cases has great importance in the present era of the rising rate of primary CS especially in rural areas.

  17. Introduction to the Special Section

    Terry-Ann Jones


    Full Text Available Several theories of international migration have emerged to explain and predict the patterns created by the international flows of people. While used as an explanatory tool for other sociological phenomena, world-systems analysis has also emerged as a dominant paradigm through which international migration may be explored. In April 2008 Fairfield University in Fairfield, CT hosted the thirty-second annual conference of the Political Economy of the World-System section of the American Sociological Association. The theme was Flow of People and Money across the World-System: Past, Present and Future. The collection of papers presented at this conference was academically rich and produced a wealth of scholarship, some of which is presented in this issue. Vernengo and Bradbury examine the risks associated with dollarization in Ecuador, arguing that although these risks are minimized by the influx of migrant remittances into the country, the trend remains unstable and unsustainable, as was evident in Argentina. Rocha deconstructs the optimistic visions that present remittances as an opportunity for developing countries, instead arguing that they are part and parcel of a process of economic imperialism. Dick and Jorgenson focus on environmental consequences of foreign investment dependence for less-developed countries and how various types of ecological degradation can contribute to mass migration. Kentor, Sobel and Timberlake discuss the hierarchy of global cities through which so much money flows back and forth, and specifically the spatiality of inter-corporate integration in the global economy such as the spatial distribution of intra-firm corporate headquarter-subsidiary networks operations and centrality in transportation networks. Lastly, Degirmen presents a case study of globalization of capital in Turkey and how interest and exchange rate shocks produced particularly interesting effects on capital and liquidity structures.

  18. Electron-Impact Ionization Cross Section Database

    SRD 107 Electron-Impact Ionization Cross Section Database (Web, free access)   This is a database primarily of total ionization cross sections of molecules by electron impact. The database also includes cross sections for a small number of atoms and energy distributions of ejected electrons for H, He, and H2. The cross sections were calculated using the Binary-Encounter-Bethe (BEB) model, which combines the Mott cross section with the high-incident energy behavior of the Bethe cross section. Selected experimental data are included.

  19. FOREWORD: Special section on imaging

    Bertero, M.; Scherzer, O.


    Imaging is a rapidly growing area in applied sciences. It has an interdisciplinary character and a wide range of applications such as medicine, nondestructive evaluation, microscopy and astronomy, as well as many industrial processes. The increasing demand on imaging is due to the change of role of vision. Today vision is not through eyes only but complemented, for instance, by ultrasound, x-ray computerized tomography (CT), electrical impedance tomography (EIT), to name but a few. Moreover, traditional imaging systems such as microscopes and telescopes are now equipped with detection instruments (CCD cameras) and the resulting digital images are currently processed and enhanced. Finally, the relevance of imaging for industry is best documented by a recent feature by Robert West (West R 2003 In industry, seeing is believing Physics World June 2003). Today the scope of imaging has broadened and plays a central role in many different areas ranging, for instance, from remote sensing to seismology. In most cases the new imaging techniques are based on indirect measurements of physical parameters; therefore they quite naturally lead to the demand of solving (linear or nonlinear) inverse problems. This indicates the central role that inverse problems have in imaging science. This special section highlights several topics of recent advances in imaging. The first five papers concern problems originating from medical imaging which can have important applications in other domains. The paper by Ji et al covers a new and promising diagnostic tool in medicine: the identification of abnormal tissues by elastic shear wave properties. The two subsequent papers by Louis and by Defrise et al concern 3D cone beam tomography which is the most recent and advanced technique in x-ray CT. Both the case of circular and helical scanning are considered. The paper by Natterer et al is also about tomography but is intended to exploit the mathematical analogies between x-ray CT and synthetic

  20. Analytical study of indications of cesarean section

    Janki M. Pandya


    Conclusions: Reduction of number of primary cesarean sections and successful VBAC trials are recommended to keep the rate of cesarean sections to the possible minimum level. [Int J Reprod Contracept Obstet Gynecol 2015; 4(5.000: 1460-1463

  1. 40 CFR 86.1204 - Section numbering.


    ... Test Procedures for New Gasoline-Fueled, Natural Gas-Fueled, Liquefied Petroleum Gas-Fueled and Methanol-Fueled Heavy-Duty Vehicles § 86.1204 Section numbering. The section numbering system set forth...

  2. Section Level Public Land Survey - lines

    Minnesota Department of Natural Resources — Public Land Survey line delineations to the section level. Developed from manually digitized section corners captured from paper USGS seven and one-half map sources.

  3. Section Level Public Land Survey - polygons

    Minnesota Department of Natural Resources — Public Land Survey line delineations to the section level. Data are derived primarily from Section corner locations captured from paper USGS seven and one-half...

  4. Evaluation of cross section for 103Rh

    A completely new evaluation for the neutron cross sections is presented. The experimental data mainly referred to EXFOR, and the recommended cross sections are compared with ENDF/B-6, BROND-2, JENDL-3.2 and JEF-2

  5. Photoproduction total cross section and shower development

    Cornet, F.; García Canal, C. A.; Grau, A.; Pancheri, G.; Sciutto, S. J.


    The total photoproduction cross section at ultrahigh energies is obtained using a model based on QCD minijets and soft-gluon resummation and the ansatz that infrared gluons limit the rise of total cross sections. This cross section is introduced into the Monte Carlo system AIRES to simulate extended air showers initiated by cosmic ray photons. The impact of the new photoproduction cross section on common shower observables, especially those related to muon production, is compared with previous results.

  6. Photoproduction total cross section and shower development

    Cornet, F; Grau, A; Pancheri, G; Sciutto, S J


    The total photoproduction cross section at ultra-high energies is obtained using a model based on QCD minijets and soft-gluon resummation and the ansatz that infrared gluons limit the rise of total cross sections. This cross section is introduced into the Monte Carlo system AIRES to simulate extended air-showers initiated by cosmic ray photons. The impact of the new photoproduction cross section on common shower observables, especially those related to muon production, is compared with previous results.

  7. 46 CFR Section 1 - Books of account.


    ... 46 Shipping 8 2010-10-01 2010-10-01 false Books of account. Section 1 Section 1 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION A-NATIONAL SHIPPING AUTHORITY PROCEDURAL RULES FOR FINANCIAL TRANSACTIONS UNDER AGENCY AGREEMENTS Accounts Section 1 Books of account. A separate set of books of account shall be opened for the purpose...

  8. JENDL gas-production cross section file

    The JENDL gas-production cross section file was compiled by taking cross-section data from JENDL-3 and by using the ENDF-5 format. The data were given to 23 nuclei or elements in light nuclei and structural materials. Graphs of the cross sections and brief description on their evaluation methods are given in this report. (author)

  9. SNL RML recommended dosimetry cross section compendium

    Griffin, P.J.; Kelly, J.G.; Luera, T.F. [Sandia National Labs., Albuquerque, NM (United States); VanDenburg, J. [Science and Engineering Associates, Inc., Albuquerque, NM (United States)


    A compendium of dosimetry cross sections is presented for use in the characterization of fission reactor spectrum and fluence. The contents of this cross section library are based upon the ENDF/B-VI and IRDF-90 cross section libraries and are recommended as a replacement for the DOSCROS84 multigroup library that is widely used by the dosimetry community. Documentation is provided on the rationale for the choice of the cross sections selected for inclusion in this library and on the uncertainty and variation in cross sections presented by state-of-the-art evaluations.

  10. Recent fission cross section standards measurements

    Wasson, O.A.


    The /sup 235/U(n,f) reaction is the standard by which most neutron induced fission cross sections are determined. Most of these cross sections are derived from relatively easy ratio measurements to /sup 235/U. However, the more difficult /sup 235/U(n,f) cross section measurements require the use of advanced neutron detectors for the determination of the incident neutron fluence. Examples of recent standard cross section measurements are discussed, various neutron detectors are described, and the status of the /sup 235/U(n,f) cross section standard is assessed. 23 refs., 8 figs., 4 tabs.

  11. Recent fission cross section standards measurements

    The 235U(n,f) reaction is the standard by which most neutron induced fission cross sections are determined. Most of these cross sections are derived from relatively easy ratio measurements to 235U. However, the more difficult 235U(n,f) cross section measurements require the use of advanced neutron detectors for the determination of the incident neutron fluence. Examples of recent standard cross section measurements are discussed, various neutron detectors are described, and the status of the 235U(n,f) cross section standard is assessed. 23 refs., 8 figs., 4 tabs

  12. Background-cross-section-dependent subgroup parameters

    A new set of subgroup parameters was derived that can reproduce the self-shielded cross section against a wide range of background cross sections. The subgroup parameters are expressed with a rational equation which numerator and denominator are expressed as the expansion series of background cross section, so that the background cross section dependence is exactly taken into account in the parameters. The advantage of the new subgroup parameters is that they can reproduce the self-shielded effect not only by group basis but also by subgroup basis. Then an adaptive method is also proposed which uses fitting procedure to evaluate the background-cross-section-dependence of the parameters. One of the simple fitting formula was able to reproduce the self-shielded subgroup cross section by less than 1% error from the precise evaluation. (author)

  13. Vertically stabilized elongated cross-section tokamak

    Sheffield, George V.


    This invention provides a vertically stabilized, non-circular (minor) cross-section, toroidal plasma column characterized by an external separatrix. To this end, a specific poloidal coil means is added outside a toroidal plasma column containing an endless plasma current in a tokamak to produce a rectangular cross-section plasma column along the equilibrium axis of the plasma column. By elongating the spacing between the poloidal coil means the plasma cross-section is vertically elongated, while maintaining vertical stability, efficiently to increase the poloidal flux in linear proportion to the plasma cross-section height to achieve a much greater plasma volume than could be achieved with the heretofore known round cross-section plasma columns. Also, vertical stability is enhanced over an elliptical cross-section plasma column, and poloidal magnetic divertors are achieved.

  14. Psychosocial Factors for Women Requesting Cesarean Section

    Yajuan Zhao; Shuangyun Chen


    Background: Rates of caesarean section are progressively increasing in many parts of the world. As a result of psychosocial factors, there has been an increasing tendency for pregnant women without justifiable medical indications for caesarean section to ask for this procedure in China. The psychosocial factors for requesting cesarean section were analyzed in our study. Methods: A self-made questionnaire and the State-Trait Anxiety Inventory (STAI) and Self-rating Depression Scale (SDS) were ...

  15. Measurements of neutron capture cross sections

    A review of measurement techniques for the neutron capture cross sections is presented. Sell transmission method, activation method, and prompt gamma-ray detection method are described using examples of capture cross section measurements. The capture cross section of 238U measured by three different prompt gamma-ray detection methods (large liquid scintillator, Moxon-Rae detector, and pulse height weighting method) are compared and their discrepancies are resolved. A method how to derive the covariance is described. (author)

  16. Compilation of cross-sections. Pt. 2

    A compilation of integrated cross-sections for hadronic reactions is presented. This is an updated version of CERN/HERA 79-1, 79-2, 79-3. It contains all data published up to the beginning of 1982, but some more recent data have also been included. Plots of the cross sections versus incident laboratory momentum are also given. This volume II contains cross-sections for K+ and K- induced reactions. (orig.)

  17. Cross Sections for Electron Collisions with Methane

    Song, Mi-Young, E-mail:; Yoon, Jung-Sik [Plasma Technology Research Center, National Fusion Research Institute, 814-2 Osikdo-dong, Gunsan, Jeollabuk-do 573-540 (Korea, Republic of); Cho, Hyuck [Department of Physics, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Itikawa, Yukikazu [Institute of Space and Astronautical Science, Sagamihara 252-5210 (Japan); Karwasz, Grzegorz P. [Faculty of Physics, Astronomy and Applied Informatics, University Nicolaus Copernicus, Grudziadzka 5, 87100 Toruń (Poland); Kokoouline, Viatcheslav [Department of Physics, University of Central Florida, Orlando, Florida 32816 (United States); Nakamura, Yoshiharu [6-1-5-201 Miyazaki, Miyamae, Kawasaki 216-0033 (Japan); Tennyson, Jonathan [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom)


    Cross section data are compiled from the literature for electron collisions with methane (CH{sub 4}) molecules. Cross sections are collected and reviewed for total scattering, elastic scattering, momentum transfer, excitations of rotational and vibrational states, dissociation, ionization, and dissociative attachment. The data derived from swarm experiments are also considered. For each of these processes, the recommended values of the cross sections are presented. The literature has been surveyed through early 2014.

  18. Ion and electron impact ionization cross sections

    Several current projects are described in which cross sections of interest to radiation physics are being measured. These include total and multiple ionization cross sections for protons on several gases covering a wide energy range, the measurement of cross sections differential in the angle and energy of ejected electrons for several gases including water vapor, and a review of proton ionization data. The work on water vapor has also been extended to electron and neutral hydrogen impact. A brief discussion is also given of some systematics of ionization cross sections. 13 references

  19. Perspectives of cesarean section in buffaloes

    G N Purohit; Mitesh Gaur; Amit Kumar; Chandra Shekher; Swati Ruhil


    Cesarean section in buffaloes is an emergency operative procedure being performed prinicipally for uncorrectable uterine torsions and for delivery of fetal monsters. Left paramedian (lateral and parallel to the milk vein) and oblique ventrolateral (above arcus cruralis) are the two common operative sites used for buffalo caesarean section. Although many anesthetic combinations including intravenous and inhalation anesthetic procedures have been experimented in the buffalo species yet most caesarean sections in buffaloes are satisfactorily performed in right lateral recumbency under mild sedation and local infiltration analgesia or paravertebral nerve blocks. The history, indications, anesthesia, operative procedures, post operative complications and future fertility following caesarean section in buffalo are described.

  20. Improved Empirical Parametrization of Fragmentation Cross Sections

    Sümmerer, Klaus


    A new version is proposed for the universal empirical formula, EPAX, which describes fragmentation cross sections in high-energy heavy-ion reactions. The new version, EPAX 3, can be shown to yield cross sections that are in better agreement with experimental data for the most neutron-rich fragments than the previous version. At the same time, the very good agreement of EPAX 2 with data on the neutron-deficient side has been largely maintained. Comparison with measured cross sections show that the bulk of the data is reproduced within a factor of about 2, for cross sections down to the pico-barn range.

  1. Section on High Resolution Optical Imaging (HROI)

    Federal Laboratory Consortium — The Section on High Resolution Optical Imaging (HROI) develops novel technologies for studying biological processes at unprecedented speed and resolution. Research...

  2. Director, Laboratory Animal Care and Use Section

    Federal Laboratory Consortium — The NIAMS Laboratory Animal Care and Use Section (LACU) provides support to all NIAMS Intramural Research Program (IRP) Branches and Laboratories using animals. The...

  3. Damage cross section library (DAMSIG77)

    The damage cross sections of various materials are converted to a data format, which can be used as library for the program SAND-II. The materials available in this library are graphite, stainless steel, aluminium, silicium, chromium, iron, nickel, copper, zirconium, molybdenum, tungsten, vanadium and niobium. A number of these materials have more than one cross section set, originating from different evaluations. Cross sections for some activation reactions, commonly used to determine thermal and fast neutron fluences have been included too. Moreover, also some artificial cross sections are introduced in this library which can be used to derive values for some physical quantities which may characterize neutron spectra

  4. Antioxidant Activity and Isolation of Luteoline from Centaurea behen L. Grown in Iran

    Esmaeili, Akbar; Mousavi, Zahra; Shokrollahi, Maryam; Shafaghat, Ali


    Flavonoids are secondary metabolites providing Ultraviolet-visible (UV) spectroscopy protection and color in almost all terrestrial plants and fruits. They have a fused ring system consisting of an aromatic ring and a benzopyran ring with a phenyl substituent. As their biological activities have an impact on human health, they serve as target molecules in the development of new drugs. The objective of this research was to study the antioxidant activity and chemical analysis of the luteoline f...

  5. Differentiation between diploid and tetraploid Centaurea phrygia: mating barriers, morphology and geographic distribution

    Koutecký, P.; Štěpánek, Jan; Baďurová, T.


    Roč. 84, č. 1 (2012), s. 1-32. ISSN 0032-7786 R&D Projects: GA ČR GA206/09/1126 Institutional research plan: CEZ:AV0Z60050516 Institutional support: RVO:67985939 Keywords : geographic distribution * polyploidy * reproductive isolation Subject RIV: EF - Botanics Impact factor: 2.833, year: 2012

  6. The Case Against (-)-Catechin Involvement in Allelopathy in Centaurea stoebe (spotted knapweed)

    Proving allelopathic chemical interference is a daunting endeavor, in that production and movement of a phytotoxin from a donor plant to a receiving plant must be demonstrated in the substrate in which the plants grow, which is usually a complex soil matrix. The soil levels or soil flux levels of th...

  7. New species in Aspergillus section Terrei

    Samson, R. A.; Peterson, S. W.; Frisvad, Jens Christian;


    Section Terrei of Aspergillus was studied using a polyphasic approach including sequence analysis of parts of the beta-tubulin and calmodulin genes and the ITS region, macro- and micromorphological analyses and examination of extrolite profiles to describe three new species in this section. Based...

  8. Compilation of cross-sections. Pt. 4

    This is the fourth volume in our series of data compilations on integrated cross-sections for weak, electromagnetic, and strong interaction processes. This volume covers data on reactions induced by photons, neutrinos, hyperons, and KL0. It contains all data published up to June 1986. Plots of the cross-sections versus incident laboratory momentum are also given. (orig.)

  9. Compilation of cross-sections. Pt. 1

    A compilation of integral cross-sections for hadronic reactions is presented. This is an updated version of CERN/HERA 79-1, 79-2, 79-3. It contains all data published up to the beginning of 1982, but some more recent data have also been included. Plots of the cross-sections versus incident laboratory momentum are also given. (orig.)

  10. Educational strategies in performing cesarean section

    Madsen, Kristine; Grønbeck, Lene; Larsen, Christian Rifbjerg;


    section, it is recommended that trainees perform 10-15 to 40 supervised cesarean sections prior to operating independently. Surgical technical skills of trainees/residents may be assessed by Objective Structured Assessment of Technical skills (OSATS), which provides a foundation for constructive feedback...

  11. H. W. Laboratory manual: 100 Area section


    The purpose of this manual is to present a Hazard Breakdown of all jobs normally encountered in the laboratory work of the three sections comprising the Analytic Section, Metallurgy and Control Division of the Technical Department. A Hazard Breakdown is a careful analysis of any job in which the source of possible dangers is clearly indicated for each particular step. The analysis is prepared by individuals who are thoroughly familiar with the specific job or procedure. It is felt that if the hazards herein outlined are recognized by the Laboratory personnel and the suggested safety cautions followed, the chance for injury will be minimized and the worker will become generally more safety conscious. The manual, which is prefaced by the general safety rules applying to all the laboratories, is divided into three main sections, one for each of the three sections into which the Laboratories Division is divided. These sections are as follows: Section 1 -- 200 Area Control; Section 2 -- 100 Area Control; Section 3 -- 300 Area Control, Essential Materials, and Methods Improvement.

  12. Nucleon-XcJ Dissociation Cross Sections

    冯又层; 许晓明; 周代翠


    Nucleon-XcJ dissociation cross sections are calculated in a constituent interexchange model in which quark-quark potential is derived from the Buchmüller-Tye quark-anti-quark potential. These new cross sections for dominant reaction channels depend on the centre-of-mass energy of the nucleon and the charmonium.

  13. 29 CFR Section 1607.16 - Definitions.


    .... Job analysis. A detailed statement of work behaviors and other information relevant to the job. L. Job description. A general statement of job duties and responsibilities. M. Knowledge. A body of information... of performance on the job. See section 5B and section 14C. E. Construct validity. Demonstrated...

  14. Along the Traces of the Conic Sections

    Toni CHEHLAROVA; Sendova, Evgenia


    Based on a geometry problem by Ivan Salabashev we demonstrate an exploratory process leading to conic sections as a locus of points. We work for the purpose with the GeoGebra dynamic software making use of different objects’ representations for explorations related with conic sections.

  15. Fission cross section calculations for Pa isotopes

    Based on the recently measured cross-section values for the neutron-induced fission of 231Pa and our experience gained with other isotopes, new self consistent neutron cross section calculations for n+231Pa have been performed up to 30 MeV. The results are quite different to the existing evaluations, especially above the first chance fission threshold. (authors)

  16. Assembling the LHC short straight sections

    Maximilien Brice


    The building where the short straight sections are being assembled, was often called ‘Lego Land’ by the workers because of the wide variety of sets of magnets and cryostats. Short straight sections contain magnets for manipulating the beam inside cryostats with liquid helium to keep the magnets at a cool 1.9 K (-271.3°C).

  17. Comparative analysis among several cross section sets

    Critical parameters were calculated using the one dimensional multigroup transport theory for several cross section sets. Calculations have been performed for water mixtures of uranium metal, plutonium metal and uranium-thorium oxide, and for metallics systems, to determine the critical dimensions of geometries (sphere and cylinder). For this aim, the following cross section sets were employed: 1) multigroup cross section sets obtained from the GAMTEC-II code; 2) the HANSEN-ROACH cross section sets; 3) cross section sets from the ENDF/B-IV, processed by the NJOY code. Finally, we have also calculated the corresponding critical radius using the one dimensional multigroup transport DTF-IV code. The numerical results agree within a few percent with the critical values obtained in the literature (where the greatest discrepancy occured in the critical dimensions of water mixtures calculated with the values generated by the NJOY code), a very good results in comparison with similar works. (Author)

  18. Photoproton cross section for 17O

    The measurement of the 17O(γ,p)16N reaction from threshold to an excitation energy of 44 MeV is presented. These results have been summed with the previously measured total photoneutron cross section to provide an approximation to the total photoabsorption cross section of 17O. The magnitude of the 17O photoabsorption cross section at the peak of the Giant Dipole Resonance is considerably less than the equivalent value for the photoabsorption cross sections of 16O and 18O. In addition, the integrated total photoabsorption cross section for 17O (up to 40 MeV) exhausts only about 58% of the sum rule; the values for the cases of 16O and 18O are significantly larger than this. The present data along with results from other reaction channels of this nucleus, were used to make spin, parity, and isospin assignments for several states in 17O. 48 refs., 4 tabs., 7 figs

  19. Recommended evaluation procedure for photonuclear cross section

    Lee, Young-Ouk; Chang, Jonghwa; Fukahori, Tokio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment


    In order to generate photonuclear cross section library for the necessary applications, data evaluation is combined with theoretical evaluation, since photonuclear cross sections measured cannot provide all necessary data. This report recommends a procedure consisting of four steps: (1) analysis of experimental data, (2) data evaluation, (3) theoretical evaluation and, if necessary, (4) modification of results. In the stage of analysis, data obtained by different measurements are reprocessed through the analysis of their discrepancies to a representative data set. In the data evaluation, photonuclear absorption cross sections are evaluated via giant dipole resonance and quasi-deutron mechanism. With photoabsorption cross sections from the data evaluation, theoretical evaluation is applied to determine various decay channel cross sections and emission spectra using equilibrium and preequilibrium mechanism. After this, the calculated results are compared with measured data, and in some cases the results are modified to better describe measurements. (author)

  20. Photoneutron cross sections for the silicon isotopes

    The photoneutron cross sections for 28Si, 29Si, and 30Si have been measured up to 33 MeV with monoenergetic photons from the annihilation in flight of fast positrons, using neutron multiplicity counting. Average neutron energies were obtained simultaneously with the cross-section data by the ring-ratio technique. The giant dipole resonance for 28Si and 30Si exhibit appreciable fragmentation; that for 29Si does not. The (γ,2n) cross section for 30Si is large; that for 29Si is consistent with zero. The (γ,1n) cross section for 30Si decreases sharply with energy to values near zero as the (γ,2n) cross section grows, then increases to appreciable values as the (γ,2n) cross section diminishes; this extreme behavior, although never seen before, is attributable to the competition between the (γ,n), (γ,2n), and (γ,pn) decay channels. Some properties of the isospin components of the giant resonance are inferred. Other features of the data, including the integrated cross sections, are found to be similar in many respects to corresponding results for the oxygen and magnesium isotopes. The 28Si nucleus is found to be a better core for 29Si and 30Si than might have been expected from previous descriptions of its open-shell character

  1. CNC Extruder for varied section extrusion

    H.J. Choi


    Full Text Available Purpose: The work presented in this paper might be used for basic data in the design of a lot extruded aluminum products using the variable section extrusion process.Design/methodology/approach: The capacity of a CNC extruder was calculated and decided as analyzing the FEM results performed by commercial software DEFORM-2D. CNC extruder and die set for variable section extrusion was invented by field extrusion experts.Findings: CNC extruder had a key role in variable extrusion process. Furthermore there was few die sets with mold feeding parts for aluminum extrusion. To be capable of extruding aluminum products with variable cross section are CNC extruder and the die set.Research limitations/implications: For future research of developed CNC extruder, frame structures of the extruder would be analyzed and designed using FE analysis. In addition CNC extruder would be operated by the control program for variable section as a PC version.Practical implications: Aluminum parts with variable section would increase as utilizing the CNC extruder and cost price of the parts be down. Many industrial products using the variable section extrusion process would be used in diverse fields.Originality/value: Extruded aluminum part with variable section is rarely used since extruders don’t be designed and developed for variable section extrusion. It is important that an extruder with CNC control, which could be easily handled and have accessible software to be operated by field user, are invented. As stated above, CNC extruder is needed for production of industrial products with variable section for today. Therefore design and development of CNC extruder having the die set for mold feeding parts was tackled in this paper as efficient approach using commercial FEM code.

  2. The 42Ca photoneutron cross section

    The measurement of the 42Ca(γ,nsub(t)) is reported here over the energy range 10.5 - 28 MeV. Bremsstrahlung radiation from the 35 MeV Betatron at this University was used to measure a yield curve of photoneutrons, from which the (γ,nsub(t)) cross section was derived. Since proton and neutron emission are the major decay modes of the giant dipole resonance, summing these cross sections approximates the photo-absorption cross section. With this information the theoretical predictions can be checked

  3. Compilation of cross-sections. Pt. 3

    A compilation of integrated cross-sections for hadronic reactions is presented. This is an updated version of CERN/HERA 79-1, 79-2, 79-3. It contains all data published up to the beginning of 1982, but some more recent data, particularly those from the CERN Collider, have also been included. Plots of the cross-sections versus incident laboratory momentum are also given. This volume III contains cross-sections for p and anti p induced reactions. (orig.)

  4. New airfoil sections for straight bladed turbine

    A theoretical investigation of aerodynamic performance for vertical axis Darrieus wind turbine with new airfoils sections is carried out. The blade section aerodynamics characteristics are determined from turbomachines cascade model. The model is also adapted to the vertical Darrieus turbine for the performance prediction of the machine. In order to choose appropriate value of zero-lift-drag coefficient in calculation, an analytical expression is introduced as function of chord-radius ratio and Reynolds numbers. New airfoils sections are proposed and analyzed for straight-bladed turbine

  5. Screening corrections to the Rutherford cross section

    Differential cross sections for elastic p-Au scattering were measured in the energy range between 0.2 and 0.8 MeV for scattering angles from 300 to 1500 in order to determine corrections to the Rutherford cross section due to the screening of the nuclear charge by the atomic electrons. Furthermore, differential cross sections have been calculated in the weakly screening region using various screening functions. A simple analytical expression has been derived for the representation of both experimental and theoretical results. (orig.)

  6. A nuclear cross section data handbook

    Fisher, H.O.M.


    Isotopic information, reaction data, data availability, heating numbers, and evaluation information are given for 129 neutron cross-section evaluations, which are the source of the default cross sections for the Monte Carlo code MCNP. Additionally, pie diagrams for each nuclide displaying the percent contribution of a given reaction to the total cross section are given at 14 MeV, 1 MeV, and thermal energy. Other information about the evaluations and their availability in continuous-energy, discrete-reaction, and multigroup forms is provided. The evaluations come from ENDF/B-V, ENDL85, and the Los Alamos Applied Nuclear Science Group T-2. Graphs of all neutron and photon production cross-section reactions for these nuclides have been categorized and plotted. 21 refs., 5 tabs.

  7. New taxa in Aspergillus section Usti

    Samson, R. A.; Varga, J.; Meijer, M.;


    Based on phylogenetic analysis of sequence data, Aspergillus section Usti includes 21 species, inducing two teleomorphic species Aspergillus heterothallicus (=Emericella heterothallica) and Fennellia monodii. Aspergillus germanicus sp. nov. was isolated from indoor air in Germany. This species ha...

  8. Differential cross sections of positron hydrogen collisions

    于荣梅; 濮春英; 黄晓玉; 殷复荣; 刘旭焱; 焦利光; 周雅君


    We make a detailed study on the angular differential cross sections of positron–hydrogen collisions by using the momentum-space coupled-channels optical (CCO) method for incident energies below the H ionization threshold. The target continuum and the positronium (Ps) formation channels are included in the coupled-channels calculations via a complex equivalent-local optical potential. The critical points, which show minima in the differential cross sections, as a function of the scattering angle and the incident energy are investigated. The resonances in the angular differential cross sections are reported for the first time in this energy range. The effects of the target continuum and the Ps formation channels on the different cross sections are discussed.

  9. Systematics of (n,2n) Cross Sections


    <正>The experimental data of (n, 2n) cross sections were collected and evaluated as complete as possible. There are 640 sets of experimental data for 130 nuclei. The data were fitted to the expressions that describe the

  10. PLSS Townships and Sections, SectionsUTM83, Published in 2006, Daggett County.

    NSGIC GIS Inventory (aka Ramona) — This PLSS Townships and Sections dataset, was produced all or in part from Other information as of 2006. It is described as 'SectionsUTM83'. Data by this publisher...

  11. PLSS Townships and Sections, Section coverage, Published in 2008, Ellsworth Community College.

    NSGIC GIS Inventory (aka Ramona) — This PLSS Townships and Sections dataset as of 2008. It is described as 'Section coverage'. Data by this publisher are often provided in UTM coordinate system; in a...

  12. The constitutionality of section 7 of the Atomic Energy Act: Section 20 GG 'Kalkar decision'

    OVG Muenster, decision dated Aug. 18th, 1977 - VII A 338/74: 'Section 7 of the Atomic Energy Act disagrees with the constitution in as far as it also allows the licensing of FBR type reactores'. The grounds upon which the judgment is based are given in detail: According to the opinion of the Senate, section 7 of the Atomic Energy Act does not conform to the principle of separation of powers (section 20, sub-section 2, sentence 2 GG), to the principle of parliamentary democracy (section 20, sub-section 1 and 2 GG) and to the principles of the law and order state (section 20, sub-section 3 GG) in as far as the present version enables the licensing of fast breeders. (orig./HP)

  13. Photoneutron cross section of 34S

    Using an enriched 34S target, the reaction 34S(γ,sn)33S has been measured from below threshold (10.4 MeV) to 28 MeV by directly counting the photoneutrons as a function of bremsstrahlung energy. The resultant cross section shows gross splitting in the GDR region. The integrated cross section is discussed in the light of the systematics of similar nuclei having two neutrons outside a doubly closed shell/sub-shell core

  14. Photoneutron cross section of 34S

    Using an enriched 34S target, the reaction 34S(γ, sn) has been measured from below threshold (10.4 MeV) to 28 MeV by directly counting the photoneutrons as a function of bremsstrahlung energy. The resultant cross section shows gross splitting in the GDR region. The integrated cross section is discussed in the light of the systematics of similar nuclei having two neutrons outside a doubly closed shell/sub-shell core. (orig.)

  15. Psychiatric illness in women requesting caesarean section

    Sydsjö, Gunilla; Möller, Louise; Lilliecreutz, Caroline; Bladh, Marie; Andolf, E; Josefsson, Ann


    Objective To compare psychiatric in-and outpatient care during the 5 years before first delivery in primiparae delivered by caesarean section on maternal request with all other primiparae women who had given birth during the same time period. Design Prospective, population-based register study. Setting Sweden. Sample Women giving birth for the first time between 2002 and 2004 (n = 64 834). Methods Women giving birth by caesarean section on maternal request (n = 1009) were compared with all ot...

  16. Microwave Transmitter With Multimode Output Section

    Hoppe, Daniel J.; Bhanji, Alaudin M.; Cormier, Reginald A.


    Output-waveguide structure transports 400 kW of continuous-wave signal power at 34.5 GHz. Transmitter generates 400 kW of continuous-wave (CW) signal power. Main feature of conceptual design of this microwave transmitter is output section. Output waveguide structure includes mode converter, directional coupler, polarization monitor, and corrugated overmoded output section. Output directional pattern suitable for antenna illumination without flared feedhorn.

  17. Automatic Morphometry of Nerve Histological Sections

    Romero, E.; Cuisenaire, O.; Denef, J.; Delbeke, J.; Macq, B.; Veraart, C.


    A method for the automatic segmentation, recognition and measurement of neuronal myelinated fibers in nerve histological sections is presented. In this method, the fiber parameters i.e. perimeter, area, position of the fiber and myelin sheath thickness are automatically computed. Obliquity of the sections may be taken into account. First, the image is thresholded to provide a coarse classification between myelin and non-myelin pixels. Next, the resulting binary image is further simplified usi...

  18. Neutron capture cross sections from Surrogate measurements

    Scielzo N.D.; Dietrich F.S.; Escher J.E.


    The prospects for determining cross sections for compound-nuclear neutron-capture reactions from Surrogate measurements are investigated. Calculations as well as experimental results are presented that test the Weisskopf-Ewing approximation, which is employed in most analyses of Surrogate data. It is concluded that, in general, one has to go beyond this approximation in order to obtain (n,γ) cross sections of sufficient accuracy for most astrophysical and nuclear-energy applications.

  19. Neutron capture cross sections from Surrogate measurements

    Scielzo N.D.


    Full Text Available The prospects for determining cross sections for compound-nuclear neutron-capture reactions from Surrogate measurements are investigated. Calculations as well as experimental results are presented that test the Weisskopf-Ewing approximation, which is employed in most analyses of Surrogate data. It is concluded that, in general, one has to go beyond this approximation in order to obtain (n,γ cross sections of sufficient accuracy for most astrophysical and nuclear-energy applications.

  20. Fibonacci Numbers, Golden Section and Applications

    Şen, Erdoğan


    In this thesis we examined mathematical properties of Fibonacci numbers and applications of this numbers in the nature,geometry and economy.We obtained Golden section and proved some mathematical identities using Golden section. Infinity of the prime numbers proved by using properties of Fibonacci numbers. Encounterings with Fibonacci numbers in the nature are examined with details. Also examples are given for relation about Fibonacci numbers and stock exchange and these are examined.

  1. Evaluation methods for neutron cross section standards

    Methods used to evaluate the neutron cross section standards are reviewed and their relative merits, assessed. These include phase-shift analysis, R-matrix fit, and a number of other methods by Poenitz, Bhat, Kon'shin and the Bayesian or generalized least-squares procedures. The problems involved in adopting these methods for future cross section standards evaluations are considered, and the prospects for their use, discussed. 115 references, 5 figures, 3 tables

  2. Methods for calculating anisotropic transfer cross sections

    The Legendre moments of the group transfer cross section, which are widely used in the numerical solution of the transport calculation can be efficiently and accurately constructed from low-order (K = 1--2) successive partial range moments. This is convenient for the generation of group constants. In addition, a technique to obtain group-angle correlation transfer cross section without Legendre expansion is presented. (author)

  3. Hotel Section Management by Using Balanced Scorecard

    Anna Lysy; Małgorzata Sztorc


    The paper presents some problems in using Balanced Scorecard (BSC) in a hotel section. Fundamental element, which marks out BSC conception, is consolidation around vision and strategy appointed by the hotel management. Well compiled strategy should join all the targets and indexes, which compose four perspectives in BSC. Hotel section is the main gaining centre in the hotel, because the service quality is the main target of management strategy. BSC is a tool, which should not only measure eff...

  4. Volcanology Section Bulletin. French Geologic Society

    This issue of the Volcanology Section Bulletin is a compilation of abstracts from the meeting the section of April, 2 1996 about the active volcanism of Central America and Mexico. The abstracts selected in this issue report on measurements of uranium, thorium and radium isotopes disequilibrium in lava, and radon fluctuations in volcanic gases. One abstract reports on new 14C datings on avalanche debris. (J.S.)

  5. Photoproton cross section for 14C

    Using bremsstrahlung, the 14C(γ,p) reaction cross section has been measured from threshold to 29 MeV. The integrated cross section up to 30 MeV is 18±3 MeV mb. Above 23.5 MeV, the reported cross section includes a contribution, estimated at 3.5 MeV mb, due to the 14C(γ,d) and 14Cγ,pn) reactions. Essentially the entire 14C(γ,p) cross section results from decay of T> dipole states. From knowledge of other decay channels estimates of the cross section, integrated to 30 MeV for the T and T> components of the giant resonance (GDR) of 81 MeV mb and 43 MeV mb are obtained. The splitting of the mean energies of the GDR isospin components is 8.5 MeV. Comparisons with several shell-model calculations are made with the data, and general agreement is found. A comparison of photonuclear absorption cross sections for 12,1314C and 16,17,18 O shows dramatic redistribution of dipole strength as neutrons are added to the core nuclei. 41 refs., 1 tab., 7 figs

  6. CAD support section: tasks and projects

    Friman, Per Olof; CERN. Geneva. TS Department


    The CAE section is well known for its daily support of CAD usage at CERN but, in fact, a large part of the section’s activity is dedicated to anticipating future needs and dealing with operating systems issues and evolution of CAD software. The section supports more than 200 professional CAD users located all around the site, and it helps many other users at CERN and outside with CAD data exchange. The section is in charge of developing tools to fulfil the specific needs of the design offices and adapting these tools to the changing hardware and software environment. As an example, the section, in collaboration with the MME design office and the survey group, has developed the DMU application, which is used extensively for the LHC integration studies. In the coming years, the big challenge for the section as well as for the design offices will be the introduction of Catia. This project, started last year, is going on to adapt Catia and its data manager SmarTeam to the tools and practices in use today. Ca...

  7. Cutting work in thick section cryomicrotomy.

    Saubermann, A J; Riley, W D; Beeuwkes, R


    The forces during cryosectioning were measured using miniature strain gauges attached to a load cell fitted to the drive arm of the Porter-Blum MT-2 cryomicrotome. Work was calculated and the data normalized to a standard (1 mm X 1 mm X 0.5 micrometer) section. Thermal energy generated was also calculated. Five parameters were studied: cutting angle, thickness, temperature, hardness, and block shape. Force patterns could be divided into three major groups thought to represent cutting (Type I), large fracture planes greater than 10 micrometer in length (Type II), and small fracture planes less than 10 micrometer in length (Type III). Type I and Type II produced satisfactory sections. Work in cutting ranged from an average of 78.4 muJ to 568.8 muJ. Cutting angle and temperature had the greatest effect on sectioning. Heat generated would be sufficient to cause through-section melting for 0.5 micrometer thick sections assuming the worst possible case, namely that all heat went into the section without loss. Presence of a Type II pattern (large fracture pattern) is thought to be presumptive evidence against thawing. PMID:606833

  8. FDAMA Section 114: Why the Renewed Interest?

    Perfetto, Eleanor M; Burke, Laurie; Oehrlein, Elisabeth M; Gaballah, Mena


    The FDA regulates the use of information by biopharmaceutical companies in their promotional activities. Section 114 of the Food and Drug Administration Modernization Act of 1997 (FDAMA) was specifically designed to allow companies to more readily disseminate health care economic information (HCEI) to those who need it for formulary decision making. However, very little HCEI has been distributed promotionally under this provision over the past 17 years. There are recent discussions by stakeholders regarding the need for updates, revisions, or guidance regarding Section 114.In light of recent renewed interest in Section 114 of the FDAMA, the purpose of this commentary is to equip managed care decision makers with the information they need to understand and respond to industry communications that are governed by Section 114. This commentary reviews and synthesizes the regulatory history and language of the statute and changes to the promotion regulation generated by Section 114. It explores the reasons for the section's limited use to date, for recent renewed interest, and why changes by various stakeholders are suggested at this time. Also discussed is what managed care pharmacists need to know about Section 114, and suggestions are included regarding the active role pharmacists can play in this change process. Renewed interest in FDAMA Section 114 appears to stem largely from the increasingly visible and growing interest in comparative effectiveness research, the emergence of "big data," the expanding range of data sources available for deriving HCEI, and recent court decisions that might indicate a change in the regulatory environment. Various stakeholders are proposing recommendations regarding changes to FDAMA Section 114. Managed care pharmacists should be aware that companies are restricted when communicating HCEI promotional messages; this may mean seeing the use of FDAMA Section 114 as the "competent and reliable" effectiveness standard in promotion. If the

  9. A Pebble Bed Reactor cross section methodology

    A method is presented for the evaluation of microscopic cross sections for the Pebble Bed Reactor (PBR) neutron diffusion computational models during convergence to an equilibrium (asymptotic) fuel cycle. This method considers the isotopics within a core spectral zone and the leakages from such a zone as they arise during reactor operation. The randomness of the spatial distribution of fuel grains within the fuel pebbles and that of the fuel and moderator pebbles within the core, the double heterogeneity of the fuel, and the indeterminate burnup of the spectral zones all pose a unique challenge for the computation of the local microscopic cross sections. As prior knowledge of the equilibrium composition and leakage is not available, it is necessary to repeatedly re-compute the group constants with updated zone information. A method is presented to account for local spectral zone composition and leakage effects without resorting to frequent spectrum code calls. Fine group data are pre-computed for a range of isotopic states. Microscopic cross sections and zone nuclide number densities are used to construct fine group macroscopic cross sections, which, together with fission spectra, flux modulation factors, and zone buckling, are used in the solution of the slowing down balance to generate a new or updated spectrum. The microscopic cross-sections are then re-collapsed with the new spectrum for the local spectral zone. This technique is named the Spectral History Correction (SHC) method. It is found that this method accurately recalculates local broad group microscopic cross sections. Significant improvement in the core eigenvalue, flux, and power peaking factor is observed when the local cross sections are corrected for the effects of the spectral zone composition and leakage in two-dimensional PBR test problems.

  10. Obstetrical correlates of the first time cesarean section, compared with the repeated cesarean section

    To determine the clinical and epidemiological characteristics in patients having their first cesarean section (FCS) and compare it with findings in patients with repeated cesarean section (RCS). This study included all the women who gave birth by cesarean sections, 817 of the total 5992 deliveries, at this unit during the study period. Data on potential risk factors for the first cesarean section (FCS) and repeated cesarean section (RCS were extracted from medical records, which were reviewed and compared between these two groups of women. Data were statistically analyzed with student t-test for comparison between means and Chi-square test for comparison between percentages. Crude odds ratio (OR) with 95% confidence interval (95% CI) were calculated. Significance was taken at p 0.05). The frequency of first cesarean section and repeat cesarean section is high in our setup. Adequate following of the programs to diminish the percentage of FCS by curtailing its predisposing factors is needed. (author)

  11. Standardization of experimental animals temporal bone sections

    Dalian Ding; Jintao Yu; Peng Li; Kelei Gao; Haiyan Jiang; Wenjuan Zhang; Hong Sun; Shankai Yin; Richard Salvi


    Preparation of the temporal bone for light microscopy is an important step in histological studies of the inner ear. Due to the complexity of structures of the inner ear, it is difficult to measure or compare structures of interest without a commonly accepted standardized measure of temporal bone sections. Therefore, standardization of temporal bone sections is very important for histological assessment of sensory hair cells and peripheral ganglion neurons in the cochlear and vestibular systems. The standardized temporal bone sectioning is oriented to a plane parallel to the outer and internal auditory canals. Sections are collected from the epitympanum to the hypotympanum to reveal layers in the order of the crista ampullaris of the superior and lateral semicircular canals, macula utriculi and macula sacculi, superior vestibular ganglion neurons, macula of saccule and inferior vestibular ganglion neurons, cochlear modiolus, endolymphatic duct and endolymphatic sac, and finally the crista ampullaris of the posterior semicircular canal. Moreover, technical details of preparing for temporal bone sectioning including fixation, decalcification, whole temporal bone staining, embedding penetration, and embedding orientation are also discussed.

  12. Verification of important cross section data

    Full text: Continuing efforts in nuclear data development have made the design of a fusion power system less uncertain. The fusion evaluated nuclear data library (FENDL) development effort since 1987 under the leadership of the IAEA Nuclear Data Section has provided a credible international library for the investigation and design of the International Thermonuclear Engineering Reactor (ITER). Integral neutronics experiments are being carried out for ITER and fusion power plant blanket and shield assemblies to validate the available nuclear database and to identify deficiencies for further improvement. Important cross section data need experimental verifications if these data are evaluated based on physics model calculations and there are no measured data points available. A particular reaction cross section is Si28(n,x)Al27, which is the important cross section to determine whether the low activation SiC composite structure can be qualified as low level nuclear waste after life time exposure in the first wall neutron environment in a fusion power plant. Measurements of helium production data for candidate fusion materials are also needed, particularly at energies above 14 MeV for the assessment of materials damage in the IFMIF neutron spectrum. To a less extent, it appears that V51(n,x)Ti50 reaction cross section also needs to be measured to further confirm a recent new evaluation of vanadium for ENDF/B-VII. (author)

  13. Reduction Methods for Total Reaction Cross Sections

    Gomes, P. R. S.; Mendes Junior, D. R.; Canto, L. F.; Lubian, J.; de Faria, P. N.


    The most frequently used methods to reduce fusion and total reaction excitation functions were investigated in a very recent paper Canto et al. (Phys Rev C 92:014626, 2015). These methods are widely used to eliminate the influence of masses and charges in comparisons of cross sections for weakly bound and tightly bound systems. This study reached two main conclusions. The first is that the fusion function method is the most successful procedure to reduce fusion cross sections. Applying this method to theoretical cross sections of single channel calculations, one obtains a system independent curve (the fusion function), that can be used as a benchmark to fusion data. The second conclusion was that none of the reduction methods available in the literature is able to provide a universal curve for total reaction cross sections. The reduced single channel cross sections keep a strong dependence of the atomic and mass numbers of the collision partners, except for systems in the same mass range. In the present work we pursue this problem further, applying the reduction methods to systems within a limited mass range. We show that, under these circumstances, the reduction of reaction data may be very useful.

  14. Youssef’s Syndrome following Cesarean Section

    Ozer Birge


    Full Text Available Youssef’s syndrome is characterized by cyclic hematuria (menouria, absence of vaginal bleeding (amenorrhea, and urinary incontinence due to vesicouterine fistula (VUF, the least common of the urogynecological fistulas. Youssef’s syndrome has a variable clinical presentation. A vesicouterine fistula is an abnormal pathway between the bladder and the uterus. The most common cause is lower segment Cesarean section. Conservative treatment may be appropriate in some cases, but surgery is the definitive treatment. Vesicouterine fistula should be suspected in cases presenting with urinary incontinence even years after Cesarean section. Diagnostic tests as well as necessary appropriate surgery should be performed on cases with suspected vesicouterine fistula. We present a 40-year-old multiparous woman with vesicouterine fistula after primary Cesarean section; she presented with urinary incontinence, hematuria, and amenorrhea 1 year after the birth. Here, we discuss our case with the help of previously published studies found in the literature.

  15. Neutron cross section of methane hydrate

    Kiyanagi, Y.; Date, S.; Horikawa, T.; Takamine, J.; Iwasa, H.; Kamiyama, T. [Graduate School of Eng., Hokkaido Univ., Sapporo (Japan); Uchida, T.; Ebinuma, T.; Narrita, H. [National Inst. of Advanced Industrial Science, Tsukisamu, Sapporo (Japan); Bennington, S.M. [ISIS Dept., Rutherford Appleton, Chilton, Didcot, Oxon (United Kingdom)


    To estimate the neutronic characteristics of methane hydrate and also to synthesize cross section data for simulation we need neutron scattering data ranging wide energy and momentum region. We performed inelastic neutron scattering experiments to get information about the neutron cross section on methane hydrate. It was found that at high momentum transfer region rotational mode as well as vibration mode showed recoil like behavior. On the other hand, at low momentum region, as well known, free rotation like energy levels were observed. The energy level of ice in methane hydrate was very similar to normal ice. The results suggest that the rough expression of the cross section of the methane hydrate is presented by linear combination of the methane and ice. (orig.)

  16. Prospects for Precision Neutrino Cross Section Measurements

    Harris, Deborah A. [Fermilab


    The need for precision cross section measurements is more urgent now than ever before, given the central role neutrino oscillation measurements play in the field of particle physics. The definition of precision is something worth considering, however. In order to build the best model for an oscillation experiment, cross section measurements should span a broad range of energies, neutrino interaction channels, and target nuclei. Precision might better be defined not in the final uncertainty associated with any one measurement but rather with the breadth of measurements that are available to constrain models. Current experience shows that models are better constrained by 10 measurements across different processes and energies with 10% uncertainties than by one measurement of one process on one nucleus with a 1% uncertainty. This article describes the current status of and future prospects for the field of precision cross section measurements considering the metric of how many processes, energies, and nuclei have been studied.

  17. Radioecological state of the Czechoslovakian Danube section

    As to be able to determine the radioactivity of the Czechoslovak section of the Danube river monthly water sampling and quarterly sediment, aquatic flora, and fauna sampling was performed. The results of this investigation have shown that the radioactivity level of our Danube section is low, consisting mostly of natural radionuclides. No relationships among respective seasons and radioactivity level were observed, neither any significant dependencies between flow rate and radionuclide level. In spite of the low radioactivity of the Czechoslovak Danube section we assume it necessary to continue in carrying out radiological analyses of water and sediment samples, as well as aquatic flora and fauna, since there are some nuclear power plants already in operation in the Danube basin and further are to be constructed or are already under construction. (author)

  18. RFQ radial matching sections and fringe fields

    The entrance radial matching section is an extremely important part of any radio-frequency quadrupole (RFQ) linac. It allows a beam having time-independent characteristics to become adapted to the time-dependent focusing in the RFQ. The matching sections proposed in this paper are defined by a four-term potential function and are very effective over lengths of 3 β lambda or longer. The fringe field at the RFQ exit is mainly of interest because of the time-varying on-axis potential. The beam can either lose or gain energy, depending on the shape of the fringe field. The same four-term potential function can be used for shaping the vanes at the exit so that the fringe fields can be controlled. This formulation also applies to exit radial matching sections, which would be useful if the beam is to enter another RFQ operated at a higher frequency. 4 references, 4 figures

  19. Temperature Dependent Neutron Scattering Sections for Polyethylene

    Hill, R E; Hill, Roger E.


    This note presents neutron scattering cross sections for polyethylene at 296 K, 77 K and 4 K derived from a new scattering kernel for neutron scattering off of hydrogen in polyethylene. The kernel was developed in ENDF-6 format as a set of S(alpha,beta) tables using the LEAPR module of the NJOY94 code package. The polyethylene density of states (from 0 to sub eV) adopted to derive the new kernel is presented. We compare our calculated room temperature total scattering cross sections and double differential cross sections at 232 meV at various angles with the available experimental data (at room temperature), and then extrapolate the calculations to lower temperatures (77K and 4K). The new temperature dependent scattering kernel gives a good quantitative fit to the available room temperature data and has a temperature dependence that is qualitatively consistent with thermodynamics.

  20. 14 CFR Section 19 - Uniform Classification of Operating Statistics


    ... Statistics Section 19 Section 19 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION... AIR CARRIERS Operating Statistics Classifications Section 19 Uniform Classification of Operating Statistics...

  1. Radiation pressure cross section for fluffy aggregates

    We apply the discrete dipole approximation (DDA) to estimate the radiation pressure cross section for fluffy aggregates by computing the asymmetry parameter and the cross sections for extinction and scattering. The ballistic particle-cluster aggregate and the ballistic cluster-cluster aggregate consisting of either dielectric or absorbing material are considered to represent naturally existing aggregates. We show that the asymmetry parameter perpendicular to the direction of wave propagation is maximized where the wavelength is comparable to the aggregate size, which may be characterized by the area-equivalent radius or the radius of gyration rather than the volume-equivalent radius. The asymmetry parameter for the aggregate depends on the morphology of the particle, but not on the constituent material. Therefore, the dependence of the radiation pressure cross section on the material composition arises mainly from that of the extinction and scattering cross sections, in other words, the single-scattering albedo. We find that aggregates consisting of high-albedo material show a large deviation of radiation pressure from the direction of incident radiation. When the aggregates are illuminated by blackbody radiation, the deviation of the radiation pressure increases with increasing temperature of the blackbody. Since the parallel component of the radiation pressure cross section for the aggregates is smaller than that for the volume-equivalent spheres at the size parameter close to unity, the Planck-mean radiation pressure cross section for the aggregates having radius comparable to the effective wavelength of radiation shows a lower value, compared with the volume-equivalent sphere. Consequently, the slope of the radiation pressure force per mass of the particle as a function of particle mass shows a lower maximum for the aggregates than for compact spherical particles. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  2. DSM-5 section III personality traits and section II personality disorders in a Flemish community sample.

    Bastiaens, Tim; Smits, Dirk; De Hert, Marc; Vanwalleghem, Dominique; Claes, Laurence


    The Personality Inventory for DSM-5 (PID-5; Krueger et al., 2012) is a dimensional self-report questionnaire designed to measure personality pathology according to the criterion B of the DSM-5 Section III personality model. In the current issue of DSM, this dimensional Section III personality model co-exists with the Section II categorical personality model derived from DSM-IV-TR. Therefore, investigation of the inter-relatedness of both models across populations and languages is warranted. In this study, we first examined the factor structure and reliability of the PID-5 in a Flemish community sample (N=509) by means of exploratory structural equation modeling and alpha coefficients. Next, we investigated the predictive ability of section III personality traits in relation to section II personality disorders through correlations and stepwise regression analyses. Results revealed a five factor solution for the PID-5, with adequate reliability of the facet scales. The variance in Section II personality disorders could be predicted by their theoretically comprising Section III personality traits, but additional Section III personality traits augmented this prediction. Based on current results, we discuss the Section II personality disorder conceptualization and the Section III personality disorder operationalization. PMID:27086247

  3. Charged particle reaction cross sections and nucleosynthesis

    The role of proton and α-particle induced reactions in carbon, neon, oxygen and silicon burning in massive stars is surveyed. The problems associated with determining thermonuclear reaction rates for reactions with widely spaced resonances and with closely spaced or overlapping resonances are discussed and the associated experimental approaches are reviewed. Experimental techniques which have been used in the measurement of reaction cross sections are discussed and their strengths and weaknesses are identified. Recent developments in attempts to establish reliable statistical-model codes for calculation of reaction cross sections are presented and discussed. The results of experimental tests of statistical model codes are summarised and evaluated

  4. Surface tensor estimation from linear sections

    Kousholt, Astrid; Kiderlen, Markus; Hug, Daniel


    From Crofton’s formula for Minkowski tensors we derive stereological estimators of translation invariant surface tensors of convex bodies in the n-dimensional Euclidean space. The estimators are based on one-dimensional linear sections. In a design based setting we suggest three types of estimators....... These are based on isotropic uniform random lines, vertical sections, and non-isotropic random lines, respectively. Further, we derive estimators of the specific surface tensors associated with a stationary process of convex particles in the model based setting....

  5. Surface tensor estimation from linear sections

    Kousholt, Astrid; Kiderlen, Markus; Hug, Daniel

    From Crofton's formula for Minkowski tensors we derive stereological estimators of translation invariant surface tensors of convex bodies in the n-dimensional Euclidean space. The estimators are based on one-dimensional linear sections. In a design based setting we suggest three types of estimators....... These are based on isotropic uniform random lines, vertical sections, and non-isotropic random lines, respectively. Further, we derive estimators of the specific surface tensors associated with a stationary process of convex particles in the model based setting....

  6. Reinforced concrete columns of variable cross section

    Brant, N.F.A.


    The results of a series of 19 full scale tests carried out on pin-ended reinforced concrete columns are reported. The columns tested had either tapered rectangular sections along the length or octagonal cross sections. All columns, except the last 6, were subjected to uniaxial eccentricities at one of the ends (the stronger end), and a nominally concentric load at the other end. For the case of the last six columns the loading applied at the stronger end was biaxially eccentric. For each of t...

  7. Neutron capture cross sections from surrogate measurements

    The prospects for determining cross sections for compound-nuclear neutron-capture reactions from Surrogate measurements are investigated. Calculations as well as experimental results are presented that test the Weisskopf-Ewing approximation, which is employed in most analyses of Surrogate data. The method is applied to the 155Gd(n,γ) reaction. It is concluded that, in general, one has to go beyond this approximation in order to obtain (n,γ) cross sections of sufficient accuracy for most astrophysical and nuclear-energy applications. (authors)

  8. Reactor Section standard analytical methods. Part 1

    Sowden, D.


    the Standard Analytical Methods manual was prepared for the purpose of consolidating and standardizing all current analytical methods and procedures used in the Reactor Section for routine chemical analyses. All procedures are established in accordance with accepted practice and the general analytical methods specified by the Engineering Department. These procedures are specifically adapted to the requirements of the water treatment process and related operations. The methods included in this manual are organized alphabetically within the following five sections which correspond to the various phases of the analytical control program in which these analyses are to be used: water analyses, essential material analyses, cotton plug analyses boiler water analyses, and miscellaneous control analyses.

  9. Precise neutron inelastic cross section measurements

    Negret, Alexandru


    The design of a new generation of nuclear reactors requires the development of a very precise neutron cross section database. Ongoing experiments performed at dedicated facilities aim to the measurement of such cross sections with an unprecedented uncertainty of the order of 5% or even smaller. We give an overview of such a facility: the Gamma Array for Inelastic Neutron Scattering (GAINS) installed at the GELINA neutron source of IRMM, Belgium. Some of the most challenging difficulties of the experimental approach are emphasized and recent results are shown.

  10. Joins of DGA modules and sectional category

    Fernández Suárez, Lucía; Ghienne, Pierre; Kahl, Thomas; Vandembroucq, Lucile


    We construct an explicit semifree model for the fiber join of two fibrations p: E --> B and p': E' --> B from semifree models of p and p'. Using this model, we introduce a lower bound of the sectional category of a fibration p which can be calculated from any Sullivan model of p and which is closer to the sectional category of p than the classical cohomological lower bound given by the nilpotency of the kernel of p^*: H^*(B;Q) --> H^*(E;Q). In the special case of the evaluation fibration X^I ...

  11. Optical Model and Cross Section Uncertainties

    Herman,M.W.; Pigni, M.T.; Dietrich, F.S.; Oblozinsky, P.


    Distinct minima and maxima in the neutron total cross section uncertainties were observed in model calculations using spherical optical potential. We found this oscillating structure to be a general feature of quantum mechanical wave scattering. Specifically, we analyzed neutron interaction with 56Fe from 1 keV up to 65 MeV, and investigated physical origin of the minima.We discuss their potential importance for practical applications as well as the implications for the uncertainties in total and absorption cross sections.

  12. Introduction to the Volume's Two Thematic Sections

    Christopher Chase-Dunn


    Full Text Available The first batch contains an article by Political Scientist Daniel Whitcncck on epistemic communities and global leadership and a special thematic section focussing around the ideas ofW. Warren Wagar regarding the future of the world-system and global politics. The second batch of papers in Volume 2 has been edited by P. Nick Kardulias of the Department of Anthropology and Sociology at Kenyon College. This special thematic section focusses on anthropological and archaeological approaches to the study of world systems.

  13. Saturation Effects in Hadronic Cross Sections

    Shoshi, Arif I.; Steffen, Frank D.


    We compute total and differential elastic cross sections of high-energy hadronic collisions in the loop-loop correlation model that provides a unified description of hadron-hadron, photon-hadron, and photon-photon reactions. The impact parameter profiles of pp and gamma*p collisions are calculated. For ultra-high energies the hadron opacity saturates at the black disc limit which tames the growth of the hadronic cross sections in agreement with the Froissart bound. We compute the impact param...

  14. Multiple simultaneous body-section radiography

    The authors report the resuts of a five-layer simultaneous multisection tomographic technique to be used in pediatric radiology, based on an appropriately selected series of Trimax rare-earth intesifying screens arranged in progressive speed order. The technique has been so far employed with excellent results in 100 children, especially during ivp, when X-ray examination is very frequently disturbed by ileo-colic gas. The many advantages of the tecnique are emphasized: a) all sections are perfectly parallel and simultaneous, in the same respiratory phas and body position; b) film density is practically identical in all sections; c) there is considerable saving in time, machine consumption, and radiation dose

  15. Covariance Evaluation Methodology for Neutron Cross Sections

    Herman,M.; Arcilla, R.; Mattoon, C.M.; Mughabghab, S.F.; Oblozinsky, P.; Pigni, M.; Pritychenko, b.; Songzoni, A.A.


    We present the NNDC-BNL methodology for estimating neutron cross section covariances in thermal, resolved resonance, unresolved resonance and fast neutron regions. The three key elements of the methodology are Atlas of Neutron Resonances, nuclear reaction code EMPIRE, and the Bayesian code implementing Kalman filter concept. The covariance data processing, visualization and distribution capabilities are integral components of the NNDC methodology. We illustrate its application on examples including relatively detailed evaluation of covariances for two individual nuclei and massive production of simple covariance estimates for 307 materials. Certain peculiarities regarding evaluation of covariances for resolved resonances and the consistency between resonance parameter uncertainties and thermal cross section uncertainties are also discussed.

  16. Temperature Dependent Neutron Scattering Sections for Polyethylene

    Hill, Roger E.; Liu, C. -Y.


    This note presents neutron scattering cross sections for polyethylene at 296 K, 77 K and 4 K derived from a new scattering kernel for neutron scattering off of hydrogen in polyethylene. The kernel was developed in ENDF-6 format as a set of S(alpha,beta) tables using the LEAPR module of the NJOY94 code package. The polyethylene density of states (from 0 to sub eV) adopted to derive the new kernel is presented. We compare our calculated room temperature total scattering cross sections and doubl...

  17. Atlas of neutron capture cross sections

    This report describes neutron capture cross sections in the range 10-5 eV - 20 MeV as evaluated and compiled in recent activation libraries. The selected subset comprise the (n,γ) cross sections for a total of 739 targets for the elements H (Z = 1, Z = 1) to Cm (Z = 96, A = 238) totaling 972 reactions. Plots of the point-wise data are shown and comparisons are made with the available experimental values at thermal energy, 30 keV and 14.5 MeV. 10 refs, 7 tabs

  18. 38 CFR 10.36 - Proof of marital cohabitation under section 602 or section 312 of the Act.


    ... cohabitation under section 602 or section 312 of the Act. 10.36 Section 10.36 Pensions, Bonuses, and Veterans... of marital cohabitation under section 602 or section 312 of the Act. In order to prove marital cohabitation within the meaning of that term as used in section 602(a) or section 312(c)1 of the Act,...

  19. Section of CMS Beam Pipe Removed


    Seven components of the beam pipe located at the heart of the CMS detector were removed in recent weeks. The delicate operations were performed in several stages as the detector was opened. Video of the extraction of one section:

  20. Fusion cross sections and the new dynamics

    The prediction of the need for an extra push over the interaction barrier in order to make the heavier nuclei fuse is made the basis of a simple algebraic theory for the energy-dependence of the fusion cross-section. A comparison with recent experiments promises to provide a quantitative test of the New Dynamics

  1. LSP-Nucleus Elastic Scattering Cross Sections

    Vergados, J. D.; Kosmas, T. S.


    We calculate LSP-nucleus elastic scattering cross sections using some representative input in the restricted SUSY parameter space. The coherent matrix elements are computed throughout the periodic table while the spin matrix elements for the proposed $^{207}Pb$ target which has a rather simple nuclear structure. The results are compared to those given from other cold dark matter detection targets.

  2. Revision of Coelogyne section Speciosae (Orchidaceae)

    Gravendeel, B.; Vogel, de, V.


    Section Speciosae Pfitzer & Kraenzl. of the genus Coelogyne Lindl. is revised. Sixteen species are recognized, including one new ( C. tommii) and one dubious species ( (C. dichroantha). Three former varieties are raised to subspecies level ( C. speciosa subsp. speciosa, subsp. incarnata and subsp. fimbriata). Two species formerly included in sect. Speciosae by several authors are excluded (C. eberhardtii and C. lawrenceana).

  3. Electron impact excitation cross sections for carbon

    Ganas, P. S.


    A realistic analytic atomic independent particle model is used to generate wave functions for the valence and excited states of carbon. Using these wave functions in conjunction with the Born approximation and the Russell-Saunders LS-coupling scheme, we calculate generalized oscillator strengths and integrated cross sections for various excitations from the 2p 2( 3P O) valence state.

  4. Electron impact excitation cross sections for carbon

    A realistic analytic atomic independent particle model is used to generate wave functions for the valence and excited states of carbon. Using these wave functions in conjunction with the Born approximation and the Russell-Saunders LS-coupling scheme, we calculate generalized oscillator strengths and integrated cross sections for various excitations from the 2p2(3P0) valence state. (orig.)

  5. Top quark cross sections and differential distributions

    Kidonakis, Nikolaos


    I present results for the top quark pair total cross section and the top quark transverse momentum distribution at Tevatron and LHC energies. I also present results for single top quark production. All calculations include NNLO corrections from NNLL threshold resummation.

  6. Announcing a New Journal Section: Community Outreach

    Evans, Michele; Moy, Beverly


    The Oncologist announces a new section, “Community Outreach,” which will provide a dedicated forum for issues of access to care and cancer prevention across the economic continuum. Community Outreach will focus on publishing high-impact clinical, prevention, and applied research, and practical information and analyses on disparities in cancer care across the economic continuum.

  7. Neutron cross sections of importance to astrophysics

    Neutron reactions of importance to the various stellar burning cycles are discussed. The role of isomeric states in the branched s-process is considered for particular cases. Neutron cross section needs for the 187Re-187Os, 87Rb-87Sr clocks for nuclear cosmochronology are discussed. Other reactions of interest to astrophysical processes are presented. 35 references

  8. 76 FR 12760 - Section 302 Report


    ... From the Federal Register Online via the Government Publishing Office LIBRARY OF CONGRESS Copyright Office Section 302 Report AGENCY: Copyright Office, Library of Congress. ACTION: Notice of inquiry... Inquiry seeking comments for a report to Congress addressing possible recommendations for phasing out...

  9. Modelisation of the fission cross section

    The neutron cross sections of four nuclear systems (n+235U, n+233U, n+241Am and n+237Np) are studied in the present document. The target nuclei of the first case, like 235U and 239Pu, have a large fission cross section after the absorption of thermal neutrons. These nuclei are called 'fissile' nuclei. The other type of nuclei, like 237Np and 241Am, fission mostly with fast neutrons, which exceed the fission threshold energy. These types of nuclei are called 'fertile'. The compound nuclei of the fertile nuclei have a binding energy higher than the fission barrier, while for the fissile nuclei the binding energy is lower than the fission barrier. In this work, the neutron induced cross sections for both types of nuclei are evaluated in the fast energy range. The total, reaction and shape-elastic cross sections are calculated by the coupled channel method of the optical model code ECIS, while the compound nucleus mechanism are treated by the statistical models implemented in the codes STATIS, GNASH and TALYS. The STATIS code includes a refined model of the fission process. Results from the theoretical calculations are compared with data retrieved from the experimental data base EXFOR. (author)

  10. Note from the Radioactive Waste Section

    TS Department


    The Radioactive Waste Section of the Radiation Protection Group wishes to announce that the radioactive waste treatment centre will be closed on Friday, 19 December. In addition, waste reception will be limited to a strict minimum on Thursday, 18 December. Users of the centre are requested to adjust their plans accordingly. For more information, call 73875.