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1.
Hydrodistillation of the dried leaves of twelve species of the genus Eucalyptus L' Hér ., i.e., E. brockwayi C. A. Gardn ., E. gracilis F. Muell ., E. gillii Maiden , E. largiflorens F. Muell ., E. loxophleba Benth ., E. occidentalis Endl ., E. oldfieldii F. Muell ., E. salmonophloia F. Muell ., E. sargentii Maiden , E. stricklandii Maiden , E. torquata Luehm ., and E. woodwardii Maiden , harvested from Hajeb Layoun arboreta (region of Kairouan, central Tunisia) in January 2005, afforded essential oils in yields varying from 0.5±0.1 to 5.7±0.5%, dependent on the species. E. sargentii and E. brockwayi provided the highest and the lowest percentage of essential oil amongst all the species examined, respectively. Analysis by GC (RI) and GC/MS allowed the identification of 133 components, representing 92.9–98.8% of the total oil. The contents of the different samples varied according to the species. The main components were 1,8‐cineole, terpinen‐4‐ol, α‐pinene ( 2 ), p‐cymene, aromadendrene ( 1 ), globulol ( 5 ), trans‐pinocarveol ( 6 ), spathulenol ( 7 ), β‐eudesmol, torquatone ( 3 ), and 4‐methylpentan‐2‐yl acetate ( 8 ). The principal component analysis and the hierarchical clustering indicated that the volatile leaf oil composition of the twelve Eucalyptus species could be clearly differentiated.  相似文献   

2.
Hydrodistillation of the dried leaves of eleven species of the genus Eucalyptus L 'Hér ., i.e., E. astringens Maiden , E. camaldulensis Dehnh ., E. diversifolia Bonpl ., E. falcata Turcz ., E. ficifolia F. Muell ., E. gomphocephala DC., E. lehmannii (Schauer ) Benth ., E. maculata Hook ., E. platypus Hook ., E. polyanthemos Schauer, and E. rudis Endl ., harvested from Korbous arboreta (region of Nabeul, northeast of Tunisia) in April 2006, afforded essential oils in yields varying from 0.1±0.1 to 3.8±0.1%, dependent on the species. E. astringens and E. ficifolia showed the highest and the lowest mean percentage of essential oil amongst all the species examined, respectively. Analysis by GC (RI) and GC/MS allowed the identification of 138 components, representing 74.0 to 99.1% of the total oil. The contents of the different samples varied according to the species. The main components were 1,8‐cineole, followed by trans‐pinocarveol ( 1 ), spathulenol ( 2 ), α‐pinene, p‐cymene, (E,E)‐farnesol, cryptone, globulol ( 3 ), β‐phellandrene, α‐terpineol, viridiflorol, and α‐eudesmol. The principal‐component and the hierarchical‐cluster analyses separated the eleven Eucalyptus leaf essential oils into seven groups, each constituting a chemotype.  相似文献   

3.
Hydrodistillation of the dried leaves of 13 species of the genus Eucalyptus L' Hér ., viz., E. bicostata Maiden, Blakely & Simmonds , E. cinerea F. Muell . ex Benth ., E. exerta F. Muell ., E. gigantea Hook . f ., E. gunnii Hook . f ., E. macarthurii Deane & Maiden ., E. macrorrhyncha F. Muell ., E. maidenii F. Muell ., E. odorata Behr ., E. pauciflora Sieber ex Sprengel , E. sideroxylon A. Cunn . ex Woolls , E. tereticornis Sm ., and E. viminalis Labill ., harvested from Souinet arboreta (region of Ain Draaham, north of Tunisia) in June 2006, afforded essential oils in yields varying from 0.5±0.2 to 3.9±0.4%, dependent on the species. E. cinerea and E. exerta provided the highest and the lowest percentage of essential oil amongst all the species examined, respectively. Analysis by GC (RI) and GC/MS allowed the identification of 142 components, representing 81.5 to 98.9% of the total oil. The contents of the different samples varied according to the species. The main components were 1,8‐cineole ( 1 ), followed by cryptone, spathulenol ( 4 ), p‐cymene ( 2 ), viridiflorol ( 6 ), globulol ( 7 ), β‐eudesmol, α‐terpineol ( 5 ), limonene ( 8 ), D ‐piperitone, α‐pinene ( 3 ), cuminal, and γ‐eudesmol. The principal component and the hierarchical cluster analyses separated the 13 Eucalyptus leaf essential oils into three groups, each constituting a chemotype.  相似文献   

4.
Hydrodistillation of the dried leaves of five species of the genus Eucalyptus L' Hér ., viz., E. dundasii Maiden , E. globulus Labill ., E. kitsoniana Maiden , E. leucoxylon F. Muell ., and E. populifolia Hook ., harvested from Jbel Abderrahman arboreta (region of Nabeul, northeast of Tunisia) in April 2006, afforded essential oils in yields varying from 0.9±0.3 to 3.8±0.6%, dependent on the species. E. globulus and E. Kitsoniana provided the highest and the lowest percentage of essential oil amongst the species examined, respectively. Analysis by GC (RI) and GC/MS allowed the identification of 127 compounds, representing 93.8 to 98.7% of the total oil composition. The contents of the different samples varied according to the species. The main components were 1,8‐cineole ( 2 ; 4.7–59.2%), followed by α‐pinene ( 1 ; 1.9–23.6%), trans‐pinocarveol ( 6 ; 3.5–21.6%), globulol ( 8 ; 4.3–12.8%), p‐cymene ( 3 ; 0.5–6.7%), α‐terpineol (1.5–4.5%), borneol (0.2–4.4%), pinocarvone (1.1–3.8%), aromadendrene (1.4–3.4%), isospathulenol (0.0–1.9%), fenchol ( 4 ; 0.1–2.5%), limonene (1.0–2.4%), epiglobulol (0.6–2.1%), viridiflorol ( 9 ; 0.8–1.8%), and spathulenol (0.1–1.6%). E. leucoxylon was the richest species in 2 . Principal component analysis (PCA) and hierarchical cluster analysis (HCA) separated the five Eucalyptus leaf essential oils into four groups, each constituting a chemotype.  相似文献   

5.
The terpenoid composition of essential oils from the leaves of five Elsholtzia species, viz., E. eriostachya Benth ., E. cristata Willd ., E. polystachya Benth ., E. flava Benth ., and E. pilosa Benth ., collected from the Himalayan region (India), was examined by GC, GC/MS, and NMR analyses. Comparison of the results with previous reports revealed new chemotypes. Cluster analysis was carried out in order to discern the similarities and differences within the essential‐oil compositions at their subspecies/chemotype level. Based on the major constituents of the essential oils, six chemical groups were obtained.  相似文献   

6.
Gongora, J., Cuddahee, R. E., do Nascimento, F. F., Palgrave, C. J., Lowden, S., Ho, S. Y. W., Simond, D., Damayanti, C. S., White, D. J., Tay, W. T., Randi, E., Klingel, H., Rodrigues‐Zarate, C. J., Allen, K., Moran, C. & Larson, G. (2011). Rethinking the evolution of extant sub‐Saharan African suids (Suidae, Artiodactyla). —Zoologica Scripta, 40, 327–335. Although African suids have been of scientific interest for over two centuries, their origin, evolution, phylogeography and phylogenetic relationships remain contentious. There has been a long‐running debate concerning the evolution of pigs and hogs (Suidae), particularly regarding the phylogenetic relationships among extant Eurasian and African species of the subfamily Suinae. To investigate these issues, we analysed the mitochondrial and nuclear DNA sequences of extant genera of Suidae from Eurasia and Africa. Molecular phylogenetic analyses revealed that all extant sub‐Saharan African genera form a monophyletic clade separate from Eurasian suid genera, contradicting previous attempts to resolve the Suidae phylogeny. Two major sub‐Saharan African clades were identified, with Hylochoerus and Phacochoerus grouping together as a sister clade to Potamochoerus. In addition, we find that the ancestors of extant African suids may have evolved separately from the ancestors of modern day Sus and Porcula in Eurasia before they colonised Africa. Our results provide a revision of the intergeneric relationships within the family Suidae.  相似文献   

7.
Mealybugs and aphids are insects which damage grass species. The effects of fungal endophytes on the feeding of the mealybug, Phenococcus solani Ferris (Homoptera: Pseudococcidae), and barley aphid, Sipha maydis Passerini (Homoptera: Aphididae), on tall fescue, Festuca arundinacea Schreb. and meadow fescue, Festuca pratensis Huds., were studied under greenhouse conditions. Mealybugs preferred endophyte‐free (E–) clones over their endophyte‐infected (E+) counterparts. E+ plants had a significantly lower number of mealybugs than E– plants. A mixture of E+ and E– plants supported intermediate mealybug numbers, between pure plantings of E+ and E– grasses. Barley aphids released on to plant materials were deterred from feeding and could not persist on E+ plants. E– plants did not survive because of aphid damage, while E+ plants generally re‐grew, but were damaged to some degree. The results showed that the use of pure stands of endophyte‐infected grasses or a mixed stand of infected and non‐infected plants may increase the persistence and durability of turf and forage grass species in the presence of foliar damaging insects.  相似文献   

8.
T.R. Birkhead 《Ibis》2001,143(2):327-348
UK Raptor Wording Group Armstrong , P. The English Country Parson: A companionship between Science and Religion. Berry , R. J. Orkney Nature. Bibby , C. J., Burgess , N.D., Hill , D.A. & Mustoe , S.H. Bird Census Techniques Böhm , C. Die Wasserpieper: Vom Meeresstrand zum Gletscherrand. Brewer , D., Diamond , A., Woodsworth , E.J., Collins , B.T. & Dunn , E.H. Canadian Atlas of Bird Banding. Volume 1: Doves, Cuckoos, and Hummingbirds through Passerines Chapman , A, The Hobby. Chiappe , L.M., Sh'uan , J., Qiang , J. & Norell , M.A. Anatomy and Systematics of the Confucius‐ornithidae (Theropoda: Aves) from the Late Mesozoic of Northeastern China. Coro Arizmendi , M. & Marquez Valdelamar , L. (eds) Areas de importancia para la Conservación de las Aves en MéAxico. Dean , W.R.J. The Birds of Angola. dolling , R.J., Fay , R.R. & Popper , A.N. (eds) Comparative Hearing: Birds and Reptiles. Elias , G. L., Reino , L. M., Silva , T., Tome , R. & Geraldes , P. Atlas das Aves Invernantes do Baixo Alentejo. Fry , C.H., Keith , S. & Urban , E.K. (eds) Birds of Africa Volume 6. Harris , T. & Franklin , K. Shrikes and Bush‐shrikes; including wood‐shrikes, helmet‐shrikes, flycatchershrikes, philentomas, batises and wattle‐eyes. Johnsgard , P.A. Trogons and Quetzals of the World. Lenz , N. Evolutionary Ecology of the Regent Bowerbird Sericulus chrysocephalus (Lewin, 1808). Olney , P.J.S., & Fisken , F.A. (eds) International Zoo Yearbook, Vol.37. Petersen , Islenskir Fuglar (Icelandic Birds) (in Icelandic). Robb, M.S. Introcuction to Vocalizations of Crossbills in North‐western Europe. Rodner , C., Lentino , M., & Restall , R. Checklist of the Birds of Nortehrn South America: an annotated checklist of the species and subspecies of Ecuador, Colombia, Venezuela, Aruba, Curaçao, Bonaire, Trinidad & Tobago, Guyana, Suriname and French Guiana. Sayre , R., Roca , E., Sedaghatkish , G., Young , B., Keel , S., Roca , R. & Shepparo , S. Nture n Focus: Rapid Ecological Assessment. Schulze ‐Hagen , K. & Geus , A. Joseph Wolf. Shawyer , C., Clarke , R. & Dixon , N. A Study into the Raptor Predation of Domestic Pigeons. Sibley , D. The North American Bird Guide. Siokhin , V.D. (ed.) Chislennost' i razmeshchenie gneziashchikhia okolovodnykh ptits v vodno‐bolotnykh ugodiakh Azovo‐Chernomorskogo poberezhia Ukrainy [Numbers and Distribution of Breeding Waterbirds in the Wetlands of the Azov‐Black Sea Region of Ukraine] (in Russian, with English summaries and captions). Skutch , A.F. Harmony and Conflict in the Living World. Snyder , N., Mc Gowan , P., Gilardi , J., & Grajal , A. (eds) Parrots. Status Survey and Conservation Action Plan 2000–2004. Storch , I. Status Survey and Conservation Action Plan 2000–2004: Grouse. Tamisier , A. & Dehorter , O. Camargue, Canards et Foulques. Tickell , W.L.N. Albatrosses. Vickery , P.D. & Herkert , R. (eds) Ecology and Conservation of Grassland Birds in the Western Hemisphere. Wilcove , D.S. The Condor's Shadow. The Loss and Recovery of Wildlife in America. Chamberlain , D.E., Fuller , R.J., Shrubb , M. Bunce , R.G.H., Duckworth , J.C, Garthwaite , D.G., Impey , A.J. & Hart , A.D.M. The Effects of Agricultural Management on Farmland Birds. Datskevich , V.A. Istoricheskii ocherk i nekotorye itogi ornitologicheskikh issledovanii v Belovezhskoi pushche (1945–1985 gg.) [Historical Survey and some Results of Ornithological Studies in the Belovezhskaya Pushcha (1945–1985)]. Fesenko , G.V. & Bokotey , A.A. Anotovanii spisok ukraînskikh naukovikh nazv ptakhiv fauni Ukraîni [The Annotated List of the Ukrainian Scientific Names of the Bird Species belonging to the Fauna of Ukraine] (in Ukrainian). Oddie , B. Bill Oddie's Birding Map of Britain & Ireland, 2nd edn. Pemberton , J.E. (ed.) The Birdwatcher's Yearbook and Diary 2001. Rusev , I.T. (ed.) Ptitsy Azovo‐Chernomorskogo regiona na rubezhe tysiacheletil: materialy iubileinoi mezhdunarodnoi nauchnoi konferentsii, posviashchennoi 20‐letiu Azovo Chernomorskoi ornitologicheskoi rabochei gruppy, Odessa 10–14 febralia 2000g [Birds of Black Sea Region on Border of Millenium] Serebryakov , V.V. & Alekseyenko , V.R. Vodno‐bolotnye ugod'ia Azovo‐Chernomorskogo poberezh'ia Ukrainy, bibliograficheskii ukazatel' 1970–1999 [Wetlands of the Azov‐Black Sea Region of Ukraine: Bibliography 1970–19991 (in Russian and English). Symanski , R. Blackhearts: Ecology in Outback Australia. World Conservation Monitoring Centre . Checklist of CITES Species: a Reference to the Appendices to the Convention on International Trade in Endangered Species of Wild Fauna and Flora. Chappuis , C. Oiseaux d'Afrique. African Bird Sounds.  相似文献   

9.
We perform phylogenetic analyses of the ‘polymorphic earless praying mantises’, a heterogeneous assemblage comprising c. 55% of mantodean diversity in the Neotropics. Bayesian and maximum‐likelihood were implemented on a DNA dataset of 9949 aligned nucleic acid characters comprising ten mitochondrial and nuclear genes. Our analyses largely resolved congruent relationships with high levels of support for higher‐level taxonomic groups, but revealed extensive inconsistencies between the resolved topology and morphology‐based classification systems. The polymorphic earless praying mantises, now granted superfamily status as the Acanthopoidea stat. n., comprises 8 families, 15 subfamilies and 18 tribes. Our newly revised organization required the following taxonomic changes: (i) Thespidae sensu n., including subfamilies Pseudopogonogastrinae subfam. n., Pseudomiopteryginae sensu n., Bantiinae subfam. n., Miobantiinae sensu n. and Thespinae sensu n. (tribes Musoniellini trib. n. and Thespini sensu n. ); (ii) Angelidae stat. n. et sensu n. ; (iii) Coptopterygidae stat. n. ; (iv) Liturgusidae sensu n. ; (v) Photinaidae stat. n., including Macromantinae stat. n., Cardiopterinae stat. n., Photiomantinae subfam. n. and Photinainae sensu n. (tribes Microphotinini trib. n., Orthoderellini stat. n. and Photinaini sensu n. ); (vi) Stenophyllidae stat. n. ; (vii) Acontistidae stat. n. ; and (viii) Acanthopidae sensu n. Our new system also resulted in the reassignment of various genera to new and existing higher‐level taxa, the exclusion of old world genera otherwise traditionally classified among the Thespidae, Liturgusidae and Angelidae, the confirmation of Stenophylla Westwood as member of this clade, and the revalidation of Paradiabantia Piza stat. r. We provide diagnoses for all suprageneric taxa using external morphological characters and male genitalia. A key to higher‐level groups is provided. We incorporate egg case structural variation as a novel approach for taxon delineation. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:29E37322‐30EB‐4F64‐80C9‐E2149B5B0195 .  相似文献   

10.
Eleven species of picture‐winged flies (Diptera: Ulidiidae: Lipsanini) have been reported attacking maize [Zea mays L. (Poaceae)] ears in the Americas. Four of these species are sweet corn pests in America north of Mexico: Chaetopsis massyla (Walker), Euxesta annonae (Fabricius), E. eluta Loew, and E. stigmatias Loew. Adults of these four species appear at the beginning of each season following maize‐free periods, suggesting other plants act as food sources for maintenance and development of these flies. Studies were conducted in Florida, USA, to evaluate the suitability of several crop and non‐crop plants commonly occurring near maize plantings as developmental hosts for these flies. Laboratory trials were conducted using laboratory colonies of C. massyla, E. eluta, and E. stigmatias to determine their developmental rates and pupal survivorship on roots, stems, leaves, or fruits of 14 crop and weed species. All three fly species completed development on all tested crops (Brassica oleracea L., Capsicum chinense Jacquin, Capsicum annum L., Carica papaya L., Persea americana Mill., Raphanus sativus L., Saccharum officinarum L., and Solanum lycopersicum L.) and weed species [Amaranthus spinosus L., Portulaca oleracea L., Sorghum halepense (L.), and Typha spp.], except for Daucus carota L. roots and Solanum tuberosum L. tubers. Findings of the current study suggest that the presence of multiple host crops in areas surrounding maize fields may help explain the occurrence of these maize‐infesting ulidiids immediately after prolonged absences of maize.  相似文献   

11.
12.
BOOK REVIEWS     
Book reviewed in this article: Hutchings, M. J., John, E. A., and Stewart, A. J. A. (eds.) The Ecological Consequences of Environmental Heterogeneity. xiii + 434 pp. Blackwell Science Ltd., Oxford. ISBN 0‐632‐05713‐0. Price: USD 47.66  相似文献   

13.
L ‐Homophenylalanine (L ‐HPA) and N6‐protected‐2‐oxo‐6‐amino‐hexanoic acid (N6‐protected‐OAHA) can be used as building blocks for the manufacture of angiotensin‐converting enzyme inhibitors. To synthesize L ‐HPA and N6‐protected‐OAHA simultaneously from 2‐oxo‐4‐phenylbutanoic acid (OPBA) and N6‐protected‐L ‐lysine, several variants of Escherichia coli aspartate aminotransferase (AAT) were developed by site‐directed mutagenesis and their catalytic activities were investigated. Three kinds of N6‐protected‐L ‐lysine were tested as potential amino donors for the bioconversion process. AAT variants of R292E/L18H and R292E/L18T exhibited specific activities of 0.70±0.01 U/mg protein and 0.67±0.02 U/mg protein to 2‐amino‐6‐tert‐butoxycarbonylamino‐hexanoic acid (BOC‐lysine) and 2‐amino‐6‐(2,2,2‐trifluoro‐acetylamino)‐hexanoic acid, respectively. E. coli cells expressing R292E/L18H variant were able to convert OPBA and BOC‐lysine to L ‐HPA and 2‐oxo‐6‐tert‐butoxycarbonylamino‐hexanoic acid (BOC‐OAHA) with 96.2% yield in 8 h. This is the first report demonstrating a process for the simultaneous production of two useful building blocks, L ‐HPA and BOC‐OAHA. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009  相似文献   

14.
Nuclear magnetic resonance (NMR) investigations on mixtures containing octakis(3‐O‐butanoyl‐2,6‐di‐O‐pentyl)‐γ‐cyclodextrin (Lipodex E) and each enantiomer of methyl‐2‐chloropropionate (MCP) ascertained the role of trace amounts of water in the enantiodiscrimination processes. Water is deeply included into the cyclodextrin and favors the formation of the inclusion complex with (S)‐MCP, whereas (R)‐MCP is only slightly affected, thus causing a significant increase of NMR differentiation. Molecular dynamics simulations were performed to shed light on the possible behavior of Lipodex E in different conditions (i.e., solvent, inclusion complexes), providing energetic and atomistic details that are in agreement with NMR observations. Chirality 27:95–103, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   

15.
In a previous study, 50 of 132 soil samples collected throughout Japan were found to be Leptospira‐positive. In the present study, three strains identified in the collected specimens, three, E8, E18 and YH101, were found to be divergent from previously described Leptospira species according to 16S ribosomal RNA gene sequence analysis. These three strains have a helical shape similar to that of typical Leptospira and were not re‐isolated from experimental mice inoculated with the cultured strains. Upon 16S ribosomal RNA gene sequence analysis, E8 was found to belong to the intermediate Leptospira species clade and E18 and YH101 to belong to the saprophytic Leptospira species clade. Based on analyses of genome‐to‐genome distances and average nucleotide identity in silico using whole genome sequences and DNA–DNA hybridization in vitro, these isolates were found to be distinct from previously described Leptospira species. Therefore, these three isolates represent novel species of the genus Leptospira for which the names Leptospira johnsonii sp. nov., (type strain E8 T, = JCM 32515 T = CIP111620 T), Leptospira ellinghausenii sp. nov., (type strain E18 T, = JCM 32516 T = CIP111618 T) and Leptospira ryugenii sp. nov., (type strain YH101 T, = JCM 32518 T = CIP111617 T) are proposed.  相似文献   

16.
Buchbesprechung     
?ulkina, V. A., Toropowa, E. J., ?ulkin, J. I., Stezow, G. J.: Agrotechnische Pflanzenschutzmethoden (russ.). Verlag JuKEA Now‐osibirsk 2000 und Verlag “Marketing”; Moskau, 2000, 336 S., ISBN 5–93 376–007–2, ISBN 7–7856–0139–7  相似文献   

17.
Cover: Validation of the H3ac ChIP‐chip data by ChIP‐qPCR and identification of sites that are consistently enriched in H3ac when CFTR localizes in the nuclear interior. Sixty‐three qPCR primer pairs (numbered 1‐63) were used. Regions A‐E are indicated. See article by Muck et al., page 2607–2621 this issue.  相似文献   

18.
This study investigates the relationship between circadian typology, i.e., morningness‐eveningness (M‐E) preference, and the occurrence and severity of premenstrual mental and physical symptoms among 154 young Japanese female university students (range, 18 to 31 yrs; mean±S.D., 20.69±3.69 yrs) and 417 junior high school students (range, 12 to 15 yrs; mean±S.D., 14.29±0.67 yrs) living in an urban or suburban area of Kochi prefecture. Female university students experienced melancholy mood more frequently than did males, and the female university students who frequently became melancholy were more evening‐typed than those who did not experience melancholy. Female university students who experienced frequent fluctuations in mood and/or menstrual pain were more evening‐typed than those who were not so affected. M‐E preference of junior high school students was not correlated with stability of mood or frequency of menstrual pain. In urban areas, however junior high school students who had very stable menstrual cycles were significantly more morning‐typed than those whose menstrual cycles were not stable. In suburban areas, the bedtimes of female junior high students who had stable menstrual cycles were significantly earlier than those whose menstrual cycle duration was not stable. A physiological relationship between the circadian system, M‐E, and attributes of the menstrual cycle seems to be present in adolescent female Japanese junior high school students.  相似文献   

19.
The Virtual Population (ViP) phantoms have been used in many dosimetry studies, yet, to date, anatomical phantom uncertainty in radiofrequency (RF) research has largely been neglected. The objective of this study is to gain insight, for the first time, regarding the uncertainty in RF‐induced fields during magnetic resonance imaging associated with tissue assignment and segmentation quality and consistency in anatomical phantoms by evaluating the differences between two generations of ViP phantoms, ViP1.x and ViP3.0. The RF‐induced 10g‐average electric (E‐) fields, tangential E‐fields distribution along active implantable medical devices (AIMD) routings, and estimated AIMD heating were compared for five phantoms that are part of both ViP1.x and ViP3.0. The results demonstrated that differences exceeded 3 dB (?29%, +41%) for local quantities and 1 dB (±12% for field, ±25% for power) for integrated and volume‐averaged quantities (e.g., estimated AIMD‐heating and 10 g‐average E‐fields), while the variation across different ViP phantoms of the same generation can exceed 10 dB (?68% and +217% for field, ?90% and +900% for power). In conclusion, the anatomical phantom uncertainty associated with tissue assignment and segmentation quality/consistency is larger than previously assumed, i.e., 0.6 dB or ±15% (k = 1) for AIMD heating. Further, multiple phantoms based on different volunteers covering the target population are required for quantitative analysis of dosimetric endpoints, e.g., AIMD heating, which depend on patient anatomy. Phantoms with the highest fidelity in tissue assignment and segmentation should be used, as these ensure the lowest uncertainty and possible underestimation of exposure. To verify that the uncertainty decreases monotonically with improved phantom quality, the evaluation of differences between phantom generations should be repeated for any improvement in segmentation. Bioelectromagnetics. 2019;40:458–471. © 2019 Bioelectromagnetics Society  相似文献   

20.
Hydrodistillation of the dried leaves of five Eucalyptus species, E. alba Reinw. ex Blume , E. citriodora Hook ., E. paniculata Sm. , harvested from Choucha arboreta (region of Sejnane, northwest of Tunisia), E. pimpiniana Maiden from Mjez Elbab arboreta (north east of Tunisia) and E. bicolor A.Cunn ex Hook from Sidi Smail arboreta (center of Tunisia), in March 2017, afforded essential oils in yields varying from 1.3±0.2 to 6.0±0.9 % according to the species. E. citriodora provided the highest mean percentage of essential oil amongst all the species. Analysis by GC (RI) and GC/MS allowed the identification of 138 components representing 84.6–98.7 % of the total oil. The content of the different samples varied according to the species. The main components were citronellol, followed by 1,8‐cineole, α‐pinene, τ‐cadinol, 7‐epi‐α‐eudesmol, trans‐pinocarveol, spathulenol, aromadendrene, γ‐cadinene and δ‐cadinene. The principal components and the hierarchical cluster analyses separated the five leaf essential oils into three groups, each group constituted a chemotype.  相似文献   

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