11,661 research outputs found
Protium sp. from Colombia collected by L. Ramos, E. Álvarez, J. Cabezas, J. Rodriguez & C. Ibañez #80
No full textFile Name: TOLI-26881-SOC-01-28-P-80.jpg
CÓDIGO FOTO: TOLI-26881-SOC-01-28-P-80-
Fotografía: SI
Nº TOLI: TOLI-26881
PARCELA: SOC-01
CÓDIGO: 28-P-80
Nº COLECTA: 80
NUEVOS COLECTORES: Laura Isabel Ramos
COLECTORES: L. Ramos, E. Álvarez, J. Cabezas, J. Rodriguez & C. Ibañez
Nº MUESTRAS MONTADAS: 1
Homologación: No homologado
Nueva fecha del evento : 21/12/2018.
Fecha del evento: 17/12/2018.
Proyecto : Recursos Botánicos Disponibles en Línea (BRAVO) para la flora Colombiana
Hábitat: Bosque húmedo tropical (bh-T)
Continente: SA
Pais: Colombia
Estado/Provincia: Meta
Municipio: Puerto López
Centro poblado / Cabecera municipal: La Serranía
Localidad: Reserva Natural El Amparo
Elevación minima en metros: 200
Elevación maxima en metros: 250
Latitud: 4.020
Longitud original: -72.600
datum geodésico: WGS 84
Latitud decimal: 4.020
Longitud decimal: -72.600
Nombre cientifico: Protium sp.
Reino: Plantae
Filo: Magnoliophyta
Clase: Equisetopsida
Orden: Sapindales
Familia nueva: Burseraceae
Género nuevo: Protium
especie nueva: sp.
: Burseraceae
genero herbario: Protium
especie herbario: sp.
Especie de herbario para TNRS: Protium sp.
Especie corregida herbario y desde TNRS: Protium indet
Familia corregida desde TNRS: Burseraceae
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Erratum to “COVID-19 in children: what did we learn from the first waveˮ [Paediatr Child Health 30 (2020) 438–443/1496] (Paediatrics and Child Health (2020) 30(12) (438–443), (S1751722220301591), (10.1016/j.paed.2020.09.005))
No full text\ua9 2021 Elsevier LtdThe publisher regrets that there is an error in author name – “Carlos R. Rodriguez-Martinez” should be changed to Carlos E. Rodriguez-Martinez. The publisher would like to apologise for any inconvenience caused
DSC evaluation of thermoxidative decomposition of extra virgin olive oil: effect of microwave and conventional heating
No full textThe aim of this work was to evaluate DSC thermal properties of extra virgin olive oil subjected to microwave and thermal heating. Fresh extra virgin olive oil was stored in dark bottles under nitrogen at room temperature before analysis. Sample were placed in a 250 ml open flask and either heated in an electric oven (with air convection) at 180°C for 30, 90, 120, 180, 360, 900 and 1440 min, or microwaved (at 2450 MHz, 0.72 kW) for 3, 6, 9, 12, 15 and 20 min. All samples were cooled at room temperature in the dark to 30°C and then analyzed. Thermograms were obtained by means of DSC, by cooling from 30 to -80°C at 2°C/min, holding 3 min at -80°C and heating from -80 to 30°C at 2°C/min. Enthalpy (H, J/g), onset (Ton), and offset (Toff) temperatures of the transitions were obtained.
Lipid crystallization Ton of fresh extra virgin olive oil was at -11°C and developed over a 35–40 degrees range. Two well defined events (minor, peaking at -16 and major peaking at -40°C) were distinguishable. Heating thermograms of fresh sample showed a minor exothermic peak and successively a major endothermic event occurring over the -18°C/12°C temperature range, with the presence of a major endothermic peak (-5°C) and a small shoulder at 8°C.
Enthalpy of both crystallization and melting transition significantly decreased in all samples with increasing length of heating treatment; this effect was more pronounced for the microwaved sample. Crystallization peak line-shape dramatically changed with increasing heating time. The major crystallization peak decreased in height, and the transition spanned over a larger temperature range, because of a significant shift of Toff towards lower temperatures. Crystallization Ton remain constant in conventionally heated samples, whereas it significantly shifted towards higher temperature in samples microwaved for at least 12 min. Melting line-shapes also dramatically changed; in fact, the major endothermic peak flattened, decreased in height, and spanned over a larger temperature range, while the minor endothermic peak disappeared in the longest treated samples. An additional endothermic peak also appeared at lower temperature after 20 and 900 min of microwave and conventional treatment, respectively. Ton of the heating transition significantly shifted towards lower temperatures at increasing treatment time.
In conclusion, changes in all thermal properties were already evident in microwaved samples after 9 minutes of treatment, whereas similar values were reached after 360 min of air convection heating
Cryptodacus bernardoi Rodriguez & Rodriguez, new species
No full textCryptodacus bernardoi Rodriguez & Rodriguez, new species Figs. 1, 2, 5 –8, 14, 15, 19, 22, 23, 28 –31, 38– 42 Diagnosis. Modified couplets to the latter are provided to include C. bernardoi. It differs from all other species of Cryptodacus in the strongly sinuous shapes of the apical section of vein R 4 + 5 and crossvein dm-m. It differs from all other species except C. obliquus Hendel in lacking brown markings on the face; from all other species except C. trinotatus by the form of the sublateral postsutural vitta on the scutum, which is almost complete, but interrupted anterior to the intra-alar seta; and from other species except C. tau (Foote) by the entirely yellow abdominal syntergite 1 + 2 (Figs. 22, 23). Other useful diagnostic characters include: gena (Figs. 5, 6,) entirely yellow; posterior side of head yellow except lateral occipital sclerite with elongate brown spot; scutellum with base brown, brown area extended to basal scutellar seta; wing (Fig. 19) cell dm with basal and apical hyaline areas, discal band covering posterior part of crossvein dm-m, middle of dm-m without brown border; abdominal tergites 3–4 with broad brown bands, that on tergite 5 sometimes narrowly divided into 3 parts; oviscape yellow (Figs. 1, 20); aculeus tip with large serrations (Figs. 28–30). Description. Length 4.8 –5.0 mm. Mesonotum length 1.5–1.7 mm. Wing length 3.2–3.5 mm, width 1.3–1.5 mm, length/width ratio: 2.3. Measurements made on holotype female and one paratype male. Head (Figs. 5–8): Mostly pale yellow. Ocellar tubercle brown. Orbital plate with irregular brown stripe. Frons with pair of large dark brown spots aligned with and including base of middle frontal seta. 3 frontal setae; 2 orbital setae, well separated, distance between them 2.3–2.6 times distance from anterior seta to eye margin. Ocellar setae weak, 1.5 –2.0 times length of ocellar tubercle. Lunule entirely dark brown. Face entirely pale yellow, without brown spots; ventral margin strongly arched; gena and postgena entirely pale yellow. Posterior side of head entirely pale yellow except lateral occipital sclerite with elongate brown spot. Clypeus, prementum and palpus entirely yellow. Antenna with scape and pedicel yellow, first flagellomere dark yellow except moderate brown on apex, elongate, 4.5 –5.0 times as long as wide, apex flattened, in lateral view rounded. Arista short pubescent on distal half. Thorax (Figs. 14, 15): Mostly dark brown to black, with following whitish markings: postpronotal lobe and presutural lateral margin of scutum, connected to band on transverse suture; band on transverse suture (interrupted medially), extended across posterior part of notopleuron and posterior margin of anepisternum, almost reaching katepisternum; elongate spot on dorsal margin of katepisternum, not extending to katepisternal seta; single medial and paired sublateral postsutural vittae on scutum, medial vitta short, extended anteriorly almost to level of transverse suture, and posteriorly to midway between levels of acrostichal and dorsocentral setae, lateral vitta connected to band on transverse suture, extending almost to level of postalar seta but not reaching intra-alar seta; rectangular area posterior and lateral to intra-alar seta; and scutellum except base, brown part extending to and including base of basal scutellar seta. Scutum entirely microtrichose. Chaetotaxy normal for genus, postpronotal, 2 notopleural, 1 anepisternal, anepimeral, katepisternal, postsutural supra-alar, intra-alar, postalar, dorsocentral, acrostichal, and 2 scutellar setae well developed. Presutural supra-alar seta relatively small, half to two-thirds size of postsutural supra-alar seta. Dorsocentral seta aligned one-half to two-thirds distance from postsutural supra-alar seta to postalar seta. Legs mostly pale yellow, mid and hind coxae with small lateral brown areas, fore and mid tibiae pale brown, hind tibia dark brown, all tarsi pale brown. Wing (Fig. 19): With 4 bands: subbasal band, entirely brown, extended from cells bc and c to midlength of vein CuA+CuP, covering base of cell br, all of cells bm and bcu, and base of cell m 4 (except bordering fold); discal band, connected to subbasal band in cell c, curved posteriorly and extended to posterior wing margin distally in cell m 4, covering cell r 1 posterior to pterostigma, base of cell r 2 + 3, apex of cell br, crossvein r-m and posterior half of crossvein dm-m, dark brown anteriorly, from cell r 1 to middle of cell dm orange medially with broad, dark brown margins, posterior quarter paler brown; narrow, brown subapical band from distal part of cell r 1 to anterior end of crossvein dm-m, faint in cells r 1 and r 2 + 3; and narrow faint brown anterior apical band from distal part of cell r 2 + 3 to apex of vein M 1. Vein M 4 very narrowly bordered by brown between subbasal and discal bands. Cell dm with anterior apical corner hyaline. Crossvein r-m at 0.71 distance from bm-m to dm-m, entirely covered by dark brown distal margin of discal band. Crossvein dm-m and apical section of vein R 4 + 5 sinuous. Abdomen (female, Figs. 1, 22, male, Figs. 2, 23): Predominantly yellow, including all of syntergite 1 + 2. Tergite 3 with broad dark brown band. Tergite 4 and female tergite 5 with broad dark brown band or series of narrowly separated rectangular marks. Male tergite 5 laterally with paired ovoid brown marks, longer than wide, and medially with much smaller, inverted U-shaped brown mark or pair of brown spots. Female tergite 6 laterally with paired rectangular brown mark, medially usually with two small brown spots. Tergites with sparse black setulae. Female terminalia (Figs. 22, 28– 31): oviscape pale yellow, 0.89–0.92 mm long (n= 2). Aculeus (Fig. 28) 0.60 mm long, tip (Figs. 29, 30) 0.10 mm long, with apical 0.04 mm triangular and serrate, 0.05 mm wide, with 6–9 teeth on each side. Two spermathecae (Fig. 31) subcylindrical, with helical surface texture and elongate base. Male terminalia (Figs. 38–42): epandrium in lateral view wider than long, dorsally dark brown with black setulae, ventrally pale brown. Lateral surstylus in lateral view 3.5 times longer than wide, with glabrous, slightly curved elongated acute apex and distinct anteromedial lobe. Medial surstylus elongate two-thirds as long as lateral surstylus. Proctiger ovoid, entirely membranous, with sparse minute brown setulae. Distiphallus (Figs. 39, 41) moderately long and slender in ventral and lateral views, apex of internal tube bilobed. Type data. Holotype ♀ (IAvH), COLOMBIA: Cundinamarca: Anolaima, Vereda Santo Domingo, finca Villa Mariana [4.80171 °N 74.47542 °W], 1532 m, multilure trap, 3 Sep 2015, P. A. Rodriguez, A. L. Norrbom. Paratypes: COLOMBIA: Cundinamarca: Anolaima, Vereda Santo Domingo, finca Villa Mariana, 1532 m, multilure trap, 3 Sep 2015, P. A. Rodriguez, A. L. Norrbom, 1 ♂ (USNM); same locality, multilure trap, 21 Sep 2015, P. A. Rodriguez, 2 ♀ (ICAMF 00000044); same, multilure trap, 28 Sep 2015, P. A. Rodriguez, 2 ♀ (FSCA); same locality, reared from fruits of Phoradendron sp. near piperoides (Kunth) Trel., collected 13 Sep 2015, emerged 1 Oct 2015, P. A. Rodriguez, 1 ♂ 2 ♀ (USNM). Guaduas, Vereda el Raisal, predio el Cajón km 39 vía Bogotá-Guaduas [5 º07’09”N 74 º 57 ’02”W], 1421 m, McPhail trap 18, 22 Aug 2014, E. Quiroga, 1 ♂ 1 ♀ (ICAMF 00000045). Distribution. Cryptodacus bernardoi is known only from Colombia in Cundinamarca department in the municipios of Anolaima and Guaduas at middle altitudes on the west side of the eastern cordillera. Host plant. Three of the paratypes were reared from tiny fruits of Phoradendron sp. near piperoides (Kunth) Trel. (Figs. 43, 44), which was found parasitizing the upper part of a Psidium guajava L. shrub. This host plant is locally known by the common names “muérdago”, “matapalo”, “injerto” and “pajarito”. Phoradendron is variously classified in the Santalaceae or Viscaceae. The only previous host data for Cryptodacus was the single record of C. silvai Lima from fruit of “herva de passarinho” (Loranthus sp.) from southern Brazil (Lima 1947). The Loranthaceae, Santalaceae (and Viscaceae, when recognized as distinct from Santalaceae) belong to the order Santalales, many of which are parasitic plants. Etymology. This species is named for José Bernardo Rodríguez, father of the senior author. Comments. This species runs with difficulty in the keys of Norrbom (1994) and Norrbom & Korytkowski (2008). C. bernardoi may be most closely related to C. lopezi Norrbom, which has a similar aculeus, or it may belong to a clade along with that species and C. tau and trinotatus. The abdominal pattern is intermediate between those species, which have a distinct medial brown vitta or pair of vittae bordered by white or yellow sublateral areas on at least tergite 5 and female tergite 6, and the predominantly brown pattern in other species. In C. bernardoi the bands on tergites 4–5 in the male and 5–6 in the female may be interrupted. These four species also have the head mostly or entirely yellow posteriorly. The males were described only for C. bernardoi, C. obliquus, C. parkeri and C. tau.Published as part of Rodriguez, Pedro Alexander, Rodriguez, Erick J., Norrbom, Allen L. & Arévalo, Emilio, 2016, A new species and new records of Cryptodacus (Diptera: Tephritidae) from Colombia, Bolivia and Peru, pp. 276-290 in Zootaxa 4111 (3) on pages 277-279, DOI: 10.11646/zootaxa.4111.3.5, http://zenodo.org/record/26487
Eremidrilus humboldti Fend & Rodriguez 2020, n. sp.
No full textEremidrilus humboldti n. sp. (Figures 3, 4, 11C)Holotype. USNM 1618760. Whole worm, incomplete (tail segments missing), with sperm in anterior spermathecae, and mature egg, slide-mounted in Canada balsam. Type Locality. USA, Idaho, Blaine Co., Corral Creek at Trail Creek, 1 Jun 2008 (Site 11, Table 1), coll. S. Fend. Paratypes. MNCN 16.03 /3111, from the type locality (Site 11), 1 Jun 2008, 1 whole-mount. USNM 1618762Trail Creek at Trail Creek Road (Site 10), 30 Jun 2000, DG, 1 dissected. USNM 1618761Site 10, 5 Sep 2004, DG, 1 whole-mount. USNM 1618763, Corral Creek1 km above Trail Creek (Site 12), 1 Jun 2016, PR and SF, 1 wholemount, DNA voucher (C. Erséus pers. com.)MNCN 16.03 /3112, Site 10, 5 Sep 2004, DG, 1 dissected. All slidemounted in Canada balsam. Other material. From the type locality (Site 11), SF, 1 Jun 2008, 1 whole-mount and 1 dissected. Site 10, 5 Sep 2004, DG, 1 mature and 3 immature whole mounts; 15 Apr 2002, SF, 6 partially-mature whole mounts. Site 12, 1 Jun 2016, PR and SF, 3 whole-mounted DNA vouchers; 26 Sep 2019, SF, 3 whole mounts, all unmated. Site 13, 26 Sep 2019, SF, 8 whole mounts and 5 whole-mounted DNA vouchers. All slide-mounted in Canada balsam. Collectors: DG = Daniel L. Gustafson, PR = Pilar Rodriguez, SF = Steven Fend. Etymology. Named for the great biologist and naturalist Alexander von Humboldt, who emphasized the relationships between species diversity and their distribution, forming the basis of biogeography, and inspiring many generations of zoologists and botanists. Description. Length 12–26 mm; 54–74 segments; diameter in X 0.4–0.7 mm. Prostomium with proboscis, the latter 300–600 µm long, diameter about 80 µm at middle. Secondary segmentation well marked from IV–IX, weak in postclitellar segments (Fig. 3A). Chaetae moderately sigmoid, with nodulus slightly distal to midpoint (0.35–0.45 the distance from the tip); in anterior bundles 113–204 µm long, shorter in II, dorsals similar in length to ventrals; in mid body segments 120–216 µm long (Fig. 3B). Genital pores all on the longitudinal lines of ventral chaetae. Male pores on prominent dome-shaped porophores (26–84 µm high, 64–120 µm wide) in X, midway between chaetae and septum X/XI (Figs. 3D,E, 4A). Two pairs simple spermathecal pores in XI and XII; those in XI midway between chaetae and posterior septum; those in XII very close to posterior septum (12/13) (Fig. 3 C–E). Female pores on 11/12. Epidermis 9–24 µm thick in anterior segments, up to 40 µm in clitellum. Clitellum in X–XIII (XIV), not greatly thickened in most specimens. Pharyngeal glands in IV–VI (VII). First nephridium at 12/13 or 13/14; pores anterior to ventral chaetae, nephridial duct tubular at pore, without forming a vesicle.Sperm sacs extend anteriorly to VIII or VII, posteriorly to XIII–XIX; egg sacs extend 1–2 segments beyond. Male funnels on 9/10 and 10/11. Vasa deferentia 18–24 µm diameter, about 250–400 µm long; posterior vasa loop into XI; both vasa join the atrium near mid-length and enter the muscle layer, opening to atrial lumen near the (ental) apical end (Figs. 3 C–E, 4C). Atria short, 172–310 µm long, entirely in X, club-shaped, ampulla gradually narrows towards the pore, not clearly separated from the ectal duct; atrium length 0.3–0.5 times body width at segment X, and 2–3 times the porophore width (Fig. 4A,B). Maximum atrium diameter 38–69 µm; epithelial cells 5–10 µm thick; atrial muscle layer thin (3–6 µm); prostate glands 10–22 µm high, usually appearing as a continuous layer over most of the atrium, but in some specimens they can be seen as distinct clusters (Fig. 4C). No obvious glands at the ectal pore.Spermathecal ampullae oval or sac-like, the first pair about 150–700 µm long, the second pair similar or slightly smaller, 170–480 µm long, sometimes without sperm (Fig. 3D). Spermathecal ducts 40–85 µm long, 25–35 µm maximum diameter, tapered to the pore (Figs. 3 C–E; 4D–F); duct epithelium with columnar cells, usually with a gradual transition to the thinner epithelium of the ampulla (Figs. 3E, 4E).Remarks.Eremidrilus humboldtin. sp. resembles the Pacific Coastal E. ritocsi Fend & Rodriguez, 2003 in the size of the atrium relative to the body diameter, and the male porophore is also similar. However, E. ritocsi has only one spermathecal segment, and the spermathecal pores are near the lateral line. Spermathecal morphology also differs: ampullae are more globular in E. ritocsi, with a characteristic sperm arrangement, and ducts are longer and more tubular (Fend & Rodriguez 2003). As in other inland species described here, E. humboldtin. sp. has two spermathecal segments; spermathecae have short, tapered ducts, spermathecal pores are in line with ventral chaetal bundles, and the pores of the second pair are close to intersegment 12/13. It is distinguished from other species of the region by its small atrium (Table 2) and by the broadly rounded male porophore, with a simple pore (Fig. 4A).Published as part of Fend, Steven & Rodriguez, Pilar, 2020, New Eremidrilus species (Clitellata: Lumbriculidae) from western North America Part 1, species with two spermathecal segments, pp. 111-131 in Zootaxa 4809 (1) on pages 116-118, DOI: 10.11646/zootaxa.4809.1.6, http://zenodo.org/record/393398
Troglodrilus galarzai Giani and Rodriguez 1988
No full textTroglodrilus galarzai (Giani and Rodriguez, 1988) (Figures 3 B, 4 G–M, 5 C–D, 6; Table 1) Tubificoides galarzai Giani and Rodriguez, 1988 (partim): Figures 3 and 4. Tubificoides galarzai: Giani et al., 2001 (partim). Troglodrilus galarzai (Giani and Rodriguez) Juget et al., 2006 (partim): Figure 2; Achurra & Rodriguez, 2008; Timm, 2009 (partim); des Chatelliers et al., 2009 (partim). Lectotype. MCN 16.03 / 3037: a dissected specimen from Argatxa cave (Santa Eufemia–Ereñozar karst unit, 15 December 1984, UTM coordinates X: 527804, Y: 4800940, Z: 5). Paralectotype. MCN 16.03 / 3038: a dissected specimen from Argatxa cave (Ereñozar karst unit, 15 December 1984). Other material. One dissected specimen from the type locality (15 December 1984), 2 dissected specimens from Goiketxe cave (27 December 2007), 27 specimens (8 dissected, 3 whole-mounted and 16 in 70 % alcohol) from Artzegi cave (18 October 2007, 7 May 2008, 30 July 2008, 17 June 2009, 17 June 2009), 7 specimens (2 dissected and 5 in 70 % alcohol) from Lapurzulo II cave (15 October 2007), 5 dissected specimens from Ubegi II spring (25 October 2007, 25 June 2008), 8 specimens (2 dissected and 6 in 70 % alcohol) from Zubialde spring (18 October 2007) and 3 dissected specimens from Mairulegorreta cave (8 November 1987). All in the collection at the University of the Basque Country (UPV/EHU). Other localities. In Santa Eufemia-Ereñozar karst unit: Goiketxe cave (UTM coordinates X: 0 537014, Y: 4797642, Z: 40). In Gorbeia karst unit: Artzegi cave (UTM coordinates X: 0 520052, Y: 4762908, Z: 807), Lapurzulo II cave (UTM coordinates X: 0 515247, Y: 4765134, Z: 850), Mairulegorreta cave (UTM coordinates X: 0 5198557, Y: 4763525, Z: 915), Ubegi II spring (UTM coordinates X: 0 516270, Y: 4766001, Z: 973) and Zubialde spring (UTM coordinates X: 0 520044, Y: 4762955, Z: 818). Taxonomic remarks. The lectotype and paralectotype were chosen among the syntypes in the National Museum of Natural Sciences (Madrid). Although the original description by Giani and Rodriguez (1988) was only based on the population of Santa Eufemia-Ereñozar karst unit, new material from Gorbeia karst unit barely modifies the range of values of some characters (Table 1). New measurements of the penial sac and the spermathecal vestibule of the lectotype and paralectotype are given after their re-examination. Main diagnostic characters for the species are: ringed glandular epidermis; comma-shaped atrium with densely granulated epithelial cells in the concave part of the atrium both ental and ectal to the prostate junction, and non granulated epithelial cells in the convex and ectal part (Fig. 3 B); large prostate, joining the atrium subapically by a stout bundle of canals (Fig. 3 B); vas deferens ciliated throughout, longer than atrium, about 20–25 µm diameter, entering the atrium apically; penial sac rounded, maximum diameter 80–110 µm (lectotype: 100 µm; paralectotype: 85 µm); thick cuticular penial sheath, of particular form and size (see measurements of characters in Table 1), with longitudinal folds. One pair of spermathecae containing spermatozeugmata; spermathecal duct narrow (25–35 µm) ending in a spherical vestibule, 75–150 µm maximum diameter (paralectotype: 105 µm). The finding of specimens in different states of development (incompletely mature) in Gorbeia karst unit has revealed details on the formation of the penial sheath. In an early state, the penis is naked and when the formation of the penial sac seems to be completed, a cuticular sheath begins to develop around the penis (d, e, f and h in Fig. 2). In the end, the cuticular sheath covers also the internal wall of the penial sac (a and b in Fig. 2; Fig. 4).Published as part of Achurra, Ainara, Chatelliers, Michel Creuze Des & Rodriguez, Pilar, 2012, Troglodrilus jugeti n. sp. (Annelida, Clitellata, Tubificinae), a new stygobiont oligochaete species from south-western Europe, pp. 35-46 in Zootaxa 3229 on page 43, DOI: 10.5281/zenodo.28034
Downstream Evolution of Perturbations in a Zero Pressure Gradient Turbulent Boundary Layer
No full textThis abstract examines the evolution of perturbations generated by various trips in a turbulent boundary layer. Measurements taken using hot wire anemometry show that the evolution towards the natural state is strongly dependent on the formation mechanisms of the boundary layer, this being different for different wall normal distribution of the trips' blockage. It is observed that standard boundary layer properties are recovered, after an adaptation region, with higher momentum thickness than the natural case. Two-point measurements with time resolved velocity in the inner region are studied to explore the different formation mechanisms
Perspectives on Arts Entrepreneurship, Part 1
No full textabstract: As the first peer reviewed research journal in the field of arts entrepreneurship, Artivate: A Journal of Arts Entrepreneurship takes its role as a framer of the discourse in and around arts entrepreneurship seriously. To advance that discourse, in addition to the articles and book reviews that have been regular features of Artivate, we have invited members of our editorial board and staff to contribute short think pieces. For these pieces we asked contributors to consider open-ended questions to which they could respond in whole or in part: what is their position in relation to arts entrepreneurship; how is arts entrepreneurship situated in relation to other disciplines or fields; what are the problems we are grappling with as scholars, practitioners, teachers, and artists; and what are the research questions we are attempting to answer individually or as a field? Following, you will find responses from: Andrew Taylor, Associate Professor of arts management at American University; Paul Bonin-Rodriguez, Assistant Professor of performance as public practice at UT-Austin and author of Performing Policy (reviewed in this issue); and Artivate’s publisher and co-editor, Linda Essig, Evelyn Smith Professor and director of the Pave Program in Arts Entrepreneurship at Arizona State
DSC analysis: a potential tool for detection of extravirgin olive oil adulteration
No full textAdulteration of extravirgin olive oil with seed oils has always represented a problem for the Mediterranean countries that produce and import this type of product. The determinations of fatty acids by gas chromatography (GC) and triacylglycerols by high-performance liquid chromatography (HPLC) are considered well-established methods for authenticity and quality control of olive oil [1, 2]. Differential Scanning Calorimetry (DSC) has been recently suggested as a valuable tool for characterization of oils from olive and other vegetable sources; the DSC parameters have been reported to well correlate with chemical parameters obtained with standard methods [3, 4]. DSC has already been applied to detect adulterated butter with beef body fat and margarine, to determine the presence of animal fat in canola oil and in palm olein, and to investigate the presence of foreign fat in chocolate [5-8].
The aim of this work was to evaluate the potential use of DSC to detect adulteration of extravergin olive oil.
Extravirgin olive oil was mixed with canola oil or sunflower oil in different percentages (60:40, 70:30, 80:20 and 95:5, w/w). Thermograms were obtained by means of DSC (TA Instruments, New Castle, DE) cooling from 30 to -80°C at 2°C/min, isothermal for 3 min and heating from -80 to 30°C at 2°C/min. The crystallization and melting profiles were obtained for of each oil and their mixtures and overlapping transitions of thermograms were deconvoluted into the individual constituent peaks using PeakFitTM software (Jandel Scientific, CA).
Addition of canola and sunflower oil significantly shifted the crystallization temperature exothermal peak of extravirgin olive oil to lower temperatures. However, the enthalpy of crystallization of extravirgin olive oil was not significantly modified by canola oil addition, but it was significantly lowered by sunflower oil, probably due to the higher linoleic acid content of the latter. The crystallization exothermic peak was deconvoluted into three distinct components, which may correspond to the three major triacylglycerol groups (monosaturated, disaturated and triunsaturated) present in the oils and their mixtures. Addition ofseed oils influenced area percentages of the deconvoluted peak, according to compositional data of the oils. In particular, the admixtures withcanola oil led to an increase of the peak area corresponding to both major saturated and unsaturated fractions. However, the addition of sunflower oil increased the peak area of the intermediate fractions.
The melting of the crystallized admixture exhibited complex lineshapes influenced by the presence of seed oils, especially at higher concentration (30-40%), reducing the area of the high-melting peak group. The addition of canola oil lowered Ton of melting curves and increased the transition range, whereas the addition of sunflower oil lowered Ton, Toff and the enthalpy of the melting curves.
References
1-Christopoulou, E, Lazaraki, M, Komaitis, M, Kaselimis, K Food Chem, 2004, 84, 463-474.
2-Andrikopoulos, NK, Giannakis, IG, Tzamtzis,V J Chromat Sci, 2001, 39, 137-145.
3-Tan, CP, Man, YB, Lipid Technol, 2002, 9, 112-115.
4-Tan, CP, Man, YB, Phytochem Anal, 2002, 13, 129-141.
5-Coni, E, Pasquale, M, Coppolelli, P, Bocca, A, J AOAC Int, 1994, 71, 807-810.
6-Marikkar, JMN, Ghazali, HM, Che Man,YB, Lai, OM., J Food Lipids, 2003, 10, 63-79.
7-Marikkar, JMN, Ghazali,HM, Che Man,YB, Lai, OM, Food Res Intern, 2002, 35, 1007-1014.
8-Lipp, M, Anklam, E, Food Chem, 1998, 62, 99-108
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