101,150 research outputs found
Halecium jaederholmi Vervoort 1972
No full textHalecium jaederholmi Vervoort, 1972 Material examined: BBB 2016: St. 18; St. 23; St. 28; St. 32; St. 38. GARCÍA 2015: St. 17 (Fig. 2L) (MACN-In: 43473, 43474, 43475, 43476). Distribution: The species had been reported in Atlantic Ocean, Argentinean continental shelf and subantarctic islands, from 41°S to 55°S by Jäderholm (1905, as Halecium arboretum), Vervoort (1972), Stepanjants (1979), Beshbeeshy & Jarms (2011). This is the first record at MPAs Namuncurá I and II. Remarks: Big, fasciculate and fertile male and female colonies were found as basibionts of other hydroids, mainly hebellids and campanularid colonies. Synonyms at the area: Halecium jäderholmi (see Oliveira et al. 2016).Published as part of Schejter, L., Genzano, G., Pérez, C. D., Acuña, F., Cordeiro, R. T. S., Silva, R. A., Garese, A. & Bremec, C. S., 2020, Checklist of Benthic Cnidaria in the SW Atlantic Ocean (54 ºS- 56 ºS), pp. 201-239 in Zootaxa 4878 (2) on page 211, DOI: 10.11646/zootaxa.4878.2.1, http://zenodo.org/record/442488
Symplectoscyphus ralphae Vervoort 1993
No full text<i>Symplectoscyphus ralphae</i> Vervoort, 1993 <p>Fig. 10 M–V</p> <p> <i>Symplectoscyphus ralphae</i> Vervoort, 1993: 270, figs 65e–f, 66a–c.</p> Material examined <p>NORFOLK 1: Stn. DW1712, two fertile colonies, ca 18 mm high, both detached from substrate (sample A) (MNHN-IK-2012-16594); two colonies, 10 and 20 mm high, the largest bearing two gonothecae (sample B), on bryozoan (MNHN-IK-2012-16595).</p> Remarks <p>The trophosomes of both samples are indistinguishable morphologically (compare Figs 10M and 10N; 10O and 10P; 10 Q–R and 10S–T), but the gonothecae they bear are different. Those in sample A are smaller, provided with 12–14 transverse ridges and a narrow, trumpet-shaped distal tube (Fig. 10U), while those in sample B are comparatively larger, exhibit about 15 ridges, and their distal tube is much wider and has an everted rim (Fig. 10V). Although the gonothecal content in sample A could not be</p> <p>confidently ascertained, it may prove to be male; that in sample B contains two large ovoid bodies (either oocytes or developing planulas), and is consequently assigned to the female sex.</p> <p> Vervoort (1993) did not compare his new species with its congeners, and the present identifications are mainly based on the shape of the gonotheca. However, other symplectoscyphid hydroids belonging to the present collection, but not included in this study, exhibit indistinguishable trophosomes, but their gonothecae are of different sizes and bear a varied number of transverse ridges. Consequently, it is felt that the discrimination of species belonging to certain morphologically related groups of <i>Symplectoscyphus</i> is not possible in the absence of molecular studies, owing to the absence of reliable morphological characters.</p> Geographical distribution <p>New Caledonia (Vervoort 1993), Norfolk Ridge (present study).</p>Published as part of <i>Galea, Horia R., 2016, Notes on some sertulariid hydroids (Cnidaria: Hydrozoa) from the tropical western Pacific, with descriptions of nine new species, pp. 1-52 in European Journal of Taxonomy 218</i> on pages 45-46, DOI: 10.5852/ejt.2016.218, <a href="http://zenodo.org/record/3840195">http://zenodo.org/record/3840195</a>
Symplectoscyphus commensalis Vervoort 1993
No full textSymplectoscyphus commensalis Vervoort, 1993 Fig. 17 F–G Symplectoscyphus commensalis Vervoort, 1993: 247, figs 56C–F, 57, 58A–E. Material examined PACIFIC OCEAN • female colony with stems up to 1 cm high on stem of sertulariid hydroid; off New Caledonia, stn DW4670; 22°58′ S, 167°24′ E; 680– 612 m; 12 Aug. 2016; KANACONO leg.; one stem was used for DNA extraction, DNA 1389; voucher MHNG-INVE- 120850; barcode identifier MK 073103; MNHN-IK-2015-399. Remarks A small species, with minute hydrothecae resembling those of S. ralphae Vervoort, 1993 through their shape and size (compare Fig. 17F with Galea 2016: fig 10Q–T). Unlike S. commensalis that forms irregularly-branched colonies (up to 2 nd order branches observed), the latter builds regularly-pinnate colonies. In addition, their respective gonothecae are different [compare Fig. 17G with Galea 2016: fig. 10U–V). Distribution Only known from off New Caledonia (Vervoort 1993; present study). ? Symplectoscyphus elongatulus Galea, sp. nov. urn:lsid:zoobank.org:act: E30569 B6-8BC4-4B3C-8E84-8EC1A2300839 Figs 16B, 17 H–J; Tables 8, 10 Diagnosis Sparingly-branched symplectoscyphid forming delicate, coplanar colonies, with erect, monosiphonic stems. Internodes long, slender, distinctly geniculate, each carrying distally a hydrotheca; the latter long, slightly conical, smooth-walled, adnate for ⅓, abaxial wall straight or nearly so, free adaxial wall imperceptibly convex proximally, and distinctly concave below aperture; adaxial cusp produced, slightly everted; eight internal, submarginal projections of perisarc. Gonothecae unknown. Etymology From the Latin ‘ ēlongo, -āvi, -āre ’, meaning ‘to lengthen’, with the apposition of the suffix ‘ -ulus, -ula, ulum ’, as a diminutive, to characterize the shape of the internodes of this delicate, straggling species. Material examined Holotype PACIFIC OCEAN • a 5.1 cm high colony without gonothecae; off New Caledonia, stn DW5010; 22°10′ S, 159°03′ E; 290–820 m; 19 Sep. 2017; KANADEEP leg.; MNHN-IK-2015-463. Description Colony erect, 5.1 cm high, arising from creeping hydrorhiza. Stem monosiphonic, flaccid, unable to support itself when out of liquid; basal 1.6 cm ahydrothecate, with smooth perisarc; remainder of stem divided into regular internodes by means of indistinct oblique nodes slanting in alternate directions; internodes distinctly geniculate, long, each bearing distally a hydrotheca; branching sparse, irregular: only two side branches, neither branching further, occur in the present specimen; they are given off laterally and in opposite directions, from below the bases of two distant stem hydrothecae, and are coplanar. Hydrothecae long, slightly conical, adnate for ⅓ or less to their corresponding internodes; abaxial wall straight for most of its length, imperceptibly convex distally; free adaxial wall slightly sigmoid, convex for most of its length, then concave towards aperture; aperture three-cusped, adaxial cusp slightly produced, latero-abaxial cusps less prominent, with rounded tips, separated by wide, shallow embayments; operculum composed of three triangular flaps meeting centrally to form a pyramidal roof; 8 internal, submarginal projections of the perisarc: one minute adaxial, two pairs of latero-adaxial, one large abaxial, and two latero-abaxial. Gonothecae not observed. Remarks Only a restricted number of congeners display a combination of long, slender, geniculate internodes and weakly-adnate hydrothecae, namely: S. amphoriferus Allman, 1877 (Millard 1977; Schuchert 2001), S. bathyalis Vervoort, 1972 (original account, Calder & Vervoort 1998), S. dentiferus (Torrey, 1902) (Nutting 1904), S. effusus Vervoort, 1993 (original account, Galea 2016), S. macrocarpus (Billard, 1918) (original account, Billard 1925), S. minutus (Nutting, 1904) (original account), S. naumovi Blanco, 1969 (Peña Cantero et al. 2002), S. nesioticus Blanco, 1977 (original account, Peña Cantero et al. 2002), S. paucicatillus Galea, 2016 (original account), S. paulensis Stechow, 1923 (Vervoort 1993; present report), S. pedunculatus (Billard, 1919) (Billard 1925; Vervoort 1993) and S. plectilis (Hickson & Gravely, 1907) (Millard 1977). However, in any of these the hydrothecae do not adopt the distinctive shape met with in S. elongatulus sp. nov., and none displays submarginal, intrathecal cusps. Through its Sertularella -like hydrothecae, provided with only three marginal cusps, the present species comes close to? Symplectoscyphus acutustriatus sp. nov. (see above), whose systematic position is discussed in the ‘Molecular study’ section. Distribution Only known from off New Caledonia (present study).Published as part of Galea, Horia R. & Schuchert, Peter, 2019, Some thecate hydroids (Cnidaria: Hydrozoa) from off New Caledonia collected during KANACONO and KANADEEP expeditions of the French Tropical Deep-Sea Benthos Program, pp. 1-70 in European Journal of Taxonomy 562 on pages 48-50, DOI: 10.5852/ejt.2019.562, http://zenodo.org/record/347430
Letter, [Author unclear] to Paulina T. Merritt
No full textHandwritten letter to Paulina Merritt from an unknown author, October 1, 1876.
Studies on the pro-oxidant chemistry of flavonoids
No full textThere is currently much interest in the development of functional foods aiming at the prevention of the development of some diseases, for example cancer, by the introduction of selected natural substances at elevated levels into the diet. The rationale for this approach is based especially on epidemiological data that indicate that food items containing such chemicals may reduce the risk of these diseases in humans. Epidemiological studies indicate, for example, that diets rich in fruit and vegetables protect against a variety of diseases, including heart diseases and certain forms of cancer. However, identification of the actual ingredient in a specific diet responsible for the beneficial health effects remains an important bottleneck for translating observational epidemiology to development of a functional food ingredient. The protection against cancer afforded by fruit and vegetables has been attributed to antioxidant micronutrients such as vitamin C, beta-carotene and vitamin E, which may act at many sites, including the stomach, intestine, lung and bladder. However, present scientific attention is focusing as well on the significance of other minor dietary components, notably the flavonoids as protectants against disease. Flavonoids are widespread in nature and are found in considerable quantities in fruits, vegetables, seeds, peel and tubers. The average Western diet may provide up to 1 g of flavonoids per day. Numerous in vitro studies show that flavonoids are potent antioxidants and metal chelators. Their potential as anti-inflammatory, antiallergic and antiviral compounds has also attracted attention. These studies provide the basis for the present rapidly increasing interest for the use of flavonoids as functional food ingredients. As a result increased human exposure to flavonoids can be expected in the near future. In shops and at the internet, food and food supplements based on (iso)flavonoids as functional ingredients are marketed. This, although hard scientific data supporting the health claims as well as data allowing a balanced risk-benefit evaluation are lacking. For flavonoids increased future human exposure regimens induce the question on their pro-oxidant chemistry. There is considerable evidence that some flavonoids are mutagenic in both bacterial and mammalian experimental systems. A high incidence of gastric cancer in some human populations has been linked to consumption of wine containing potentially mutagenic flavonoids (Tamura et al. , Proc. Natl. Acad. Sci. USA. 77, 4961-4965, 1980, Hoey et al. , Am. J. Epidemiol., 113, 669-974, 1981). Relatively little is understood about either the toxicity or protection afforded by flavonoids in humans.Since flavonoid quinone/quinone methides have been suggested as the major metabolites responsible for the possible pro-oxidant toxicity and mutagenicity of flavonoids, characterisation of flavonoid quinone chemistry is of importance. However, little information is available on the structure and reactivity of these flavonoid oxidation products. Therefore, the objective of this thesis was to investigate the pro-oxidant chemistry of flavonoids and to perform structure activity studies on the chemical behaviour of 3',4'-dihydroxyflavonoids with special emphasis on the nature and reactivity of the quinone/quinone methide type metabolites formed. Using the GSH trapping method, HPLC, LC/MS, MALDI-TOF, 1H NMR, 13C NMR and quantum mechanical computer calculations the quinone/quinone methide chemistry of a series of 3',4'-dihydroxyflavonoids could be characterised.The results provide insight in structure-activity-relationships for the pro-oxidant chemistry of these electrophilic quinone/quinone methide flavonoid metabolites. The results obtained also reveal an unexpected pH-dependent electrophilic behaviour of B ring catechol flavonoids. Furthermore the results of this thesis also reveal, for the first time, evidence for the pro-oxidative chemistry of quercetin in a cellular in vitro model. The formation of these glutathionyl-flavonoid adducts provides evidence for the actual pro-oxidative formation of reactive quinone type metabolites from B ring catechol flavonoids in the selected cellular in vitro model using melanoma cells. Oxidation of the catechols to quinones and their isomeric quinone methides generates potent electrophiles that could alkylate DNA. Interestingly, the structural requirements essential for good antioxidant activity match the requirements essential for pro-oxidant action and quinone methide formation. Altogether, the pro-oxidant behaviour of flavonoids and their quinone/quinone methides are far from straight forward and need to be re-evaluated especially in the framework of the risk-benefit evaluation of the use of these flavonoids as functional food ingredients and/or food supplements.SamenvattingEr is momenteel veel interesse voor de ontwikkeling van functionele voedingsmiddelen (functional foods), met als doel het voorkomen van het ontstaan van ziekten zoals bijvoorbeeld kanker, via het in verhoogde mate introduceren van geselecteerde natuurlijke bestanddelen in het dieet. De basis voor deze aanpak wordt momenteel met name gevonden in epidemiologische studies die laten zien dat diëten rijk aan specifieke voedselcomponenten of ingrediënten de kans op bepaalde ziekten bij de mens verlagen. Zo geven epidemiologische studies bijvoorbeeld aan dat diëten die rijk zijn aan fruit en groenten beschermen tegen een aantal ziekten zoals hartziekten en bepaalde vormen van kanker. Echter, het identificeren van de belangrijke ingrediënten in het betreffende dieet die het gezondheidsbevorderende effect tot stand brengen is een knelpunt voor het vertalen van de resultaten uit de epidemiologie naar de ontwikkeling van een functioneel voedingsingrediënt.De bescherming tegen kanker door groenten en fruit is toegeschreven aan antioxidanten zoals vitamine C, beta-caroteen en vitamine E, die op vele plaatsen in het lichaam, zoals de maag, darmen, long en de blaas actief zijn. Wetenschappelijk wordt momenteel veel aandacht besteed aan het mogelijke belang van andere belangrijke dieet componenten, zoals flavonoïden, als beschermende ingrediënten tegen ziekte. Flavonoïden komen in de natuur veel voor, en worden met name in hoge concentraties gevonden in fruit, groenten, knollen en zaden. Het gemiddelde Westerse dieet bevat ongeveer 1 gram aan flavonoïden per dag.Vele in vitro studies tonen aan dat flavonoïden goede antioxidanten en metaal chelatoren zijn. Daarnaast hebben ze anti-inflammatoire, anti-allergische en anti-virale eigenschappen die van belang worden geacht. Deze bevindingen verschaffen de basis voor de momenteel snel groeiende interesse om flavonoïden te gebruiken als functionele voedingsingrediënten. Als gevolg hiervan zou er in de nabije toekomst een toename in de opname van flavonoïden via het dieet verwacht kunnen worden. In winkels en via het internet worden voedingsmiddelen en voedingssupplementen gebaseerd op (iso)flavonoïden als functionele voedingsingrediënten verkocht. Dit, terwijl zowel de wetenschappelijke onderbouwing voor de gezondheidsclaims als gegevens die een gebalanceerde "risk-benefit" analyse mogelijk maken, nog ontbreken. In het geval van verhoogde toekomstige blootstelling van mensen aan flavonoïden worden voor de risk-benefit evaluatie vragen van belang rond hun mogelijk pro-oxidatieve chemisch gedrag. Er zijn aanwijzingen dat sommige flavonoïden mutageen zijn in zowel bacteriële als zoogdier in vitro test systemen. Een verhoogde mate aan maagkanker in bepaalde humane populaties is in verband gebracht met de consumptie van wijn met daarin mogelijk mutagene flavonoïden (Tamura et al. , Proc. Natl. Acad. Sci. USA. 77, 4961-4965, 1980, Hoey et al. , Am. J. Epidem., 113, 669-974, 1981). Alles samenvattend is er eigenlijk weinig bekend van de schadelijke maar ook van de gezondheidsbevorderende effecten van flavonoïden.Omdat flavonoid chinon/chinon methides genoemd zijn als de belangrijkste metabolieten die verantwoordelijk zouden zijn voor de mogelijke pro-oxidatieve toxiciteit en mutageniteit van flavonoïden, is karakterisering van deze pro-oxidant chemie van flavonoïden van belang. Echter er is weinig bekend over de structuur en de reactiviteit van deze flavonoid oxidatie producten. Daarom was het doel van deze studie de pro-oxidant chemie van flavonoïden te onderzoeken en een structuur-activiteits studie uit te voeren naar het chemische gedrag van 3',4'-dihydroxyflavonoïden. Daarbij werd speciale aandacht besteed aan de aard en reactiviteit van de gevormde chinon/chinon methide metabolieten. Met behulp van de GSH-trapping methode, HPLC, LC/MS, MALDI-TOF, 1H-NMR, 13C-NMR en kwantum-chemische computerberekeningen kon de chinon/chinon methide chemie van een serie 3',4'-dihydroxyflavonoiden gekarakteriseerd worden.De verkregen resultaten geven inzicht in de structuur-activteits relaties voor de pro-oxidatieve chemie van de electrofiele chinon /chinon methides metabolieten van de flavonoïden. De resultaten laten ook een onverwacht effect zien van de pH op het electrofiele gedrag van de B-ring catechol flavonoïden. Bovendien laten de resultaten van het proefschrift zien dat zelfs onder reducerende omstandigheden in een cellulair in vitro model (melanoma cellen) de pro-oxidatieve chemie van quercetine van belang kan zijn. Met name de vorming van glutathion-flavonoid conjugaten is een bewijs dat in het gekozen cellulaire model de pro-oxidatieve vorming van reactieve flavonoid chinon/ chinon methide metabolieten is opgetreden. Oxidatie van de catecholen naar chinonen en hun isomere chinon methides genereert electrofielen die DNA kunnen alkyleren. Van belang is dat de structurele randvoorwaarden die een flavonoid een goede antioxidant maken gelijk blijken te zijn aan de structurele kenmerken die essentieel zijn voor pro-oxidant gedrag en chinon methide vorming.Al met al is de pro-oxidant chemie van flavonoïden en van hun chinon /chinon methides verre van recht toe recht aan gebleken en zou de pro-oxidatieve chemie en de toxiciteit van de flavonoïden in het kader van hun gebruik als functional food ingredienten beter onderzocht en afgewogen moeten worden, rekening houdend met hun mogelijk gezondheidsbevorderende effecten
Handwritten biographical information on Paulina T. McClung Merritt
No full textA handwritten biography of Paulina T. McClung Merritt by an unknown author, 1892.
Heterogeneous and tissue-specific regulation of effector T cell responses by IFN-gamma during Plasmodium berghei ANKA infection.
No full textIFN-γ and T cells are both required for the development of experimental cerebral malaria during Plasmodium berghei ANKA infection. Surprisingly, however, the role of IFN-γ in shaping the effector CD4(+) and CD8(+) T cell response during this infection has not been examined in detail. To address this, we have compared the effector T cell responses in wild-type and IFN-γ(-/-) mice during P. berghei ANKA infection. The expansion of splenic CD4(+) and CD8(+) T cells during P. berghei ANKA infection was unaffected by the absence of IFN-γ, but the contraction phase of the T cell response was significantly attenuated. Splenic T cell activation and effector function were essentially normal in IFN-γ(-/-) mice; however, the migration to, and accumulation of, effector CD4(+) and CD8(+) T cells in the lung, liver, and brain was altered in IFN-γ(-/-) mice. Interestingly, activation and accumulation of T cells in various nonlymphoid organs was differently affected by lack of IFN-γ, suggesting that IFN-γ influences T cell effector function to varying levels in different anatomical locations. Importantly, control of splenic T cell numbers during P. berghei ANKA infection depended on active IFN-γ-dependent environmental signals--leading to T cell apoptosis--rather than upon intrinsic alterations in T cell programming. To our knowledge, this is the first study to fully investigate the role of IFN-γ in modulating T cell function during P. berghei ANKA infection and reveals that IFN-γ is required for efficient contraction of the pool of activated T cells
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Pelevin’s Trinity in the novel “t”: author – protagonist – reader
No full textThe article attempts to interpret Pelevin's artistic strategy in the novel "T" by exploring its subject organization and addressing the key problems of the author, the protagonist, and the reader as they are seen by the researcher. The article analyzes the peculiarities of constructing the narrative reality in the novel "T", and goes on to discuss Pelevin's philosophic models of the development of the humankind, and the emergence of his new anthropology
Measuring industry-science links through inventor-author relations: A profiling method
No full textIn this pilot study we examine the performance of text-based profiling in recovering a set of validated inventor-author links. In a first step we match patents and publications solely based on their similarity in content. Next, we compare inventor and author names on the highest ranked matches for the occurrence of name matches. Finally, we compare these candidate matches with the names listed in a validated set of inventor-author names. Our text-based profile methodology performs significantly better than a random matching of patents and publications, suggesting that text-based profiling is a valuable complementary tool to the name searches used in previous studies.innovation; industry-science links; text-based profiling;
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