Azaspiracid shellfish poisoning: a review on the chemistry, ecology, and toxicology with an emphasis on human health impacts          下载免费PDF全文

Twiner MJ  Rehmann N  Hess P  Doucette GJ 《Marine drugs》2008,6(2):39-72

Azaspiracids (AZA) are polyether marine toxins that accumulate in various shellfish species and have been associated with severe gastrointestinal human intoxications since 1995. This toxin class has since been reported from several countries, including Morocco and much of western Europe. A regulatory limit of 160 microg AZA/kg whole shellfish flesh was established by the EU in order to protect human health; however, in some cases, AZA concentrations far exceed the action level. Herein we discuss recent advances on the chemistry of various AZA analogs, review the ecology of AZAs, including the putative progenitor algal species, collectively interpret the in vitro and in vivo data on the toxicology of AZAs relating to human health issues, and outline the European legislature associated with AZAs.  相似文献   

Phylogeny and relationships in Daucus based on restriction fragment length polymorphisms (RFLPs) of the chloroplast and mitochondrial genomes     

B.S. Vivek  Philipp W. Simon 《Euphytica》1999,105(3):183-189

Chloroplast DNA (cpDNA) restriction site analysis of nine species of Daucus (covering four of five sections) and nine carrot accessions was done using 14 Petunia cpDNA clones as probes and 10 restriction enzymes. Cladistic analysis yielded a phylogeny generally concordant with a recent morphological classification. A cpDNA insertion-deletion mutation was found in the cultivated carrots (probe P10– Bgl II digest). Mitochondrial DNA (mtDNA) restriction site analysis of the same material using four maize mtDNA clones as probes and 10 enzymes exhibited extensive mitochondrial diversity in Daucus, both within and between sections. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

The urban governance of brownfield restructuring in China: The case of Guangzhou's T.I.T Creative Industry Zone          下载免费PDF全文

Philipp Zielke  Michael Waibel 《Asia Pacific viewpoint》2016,57(1):91-105

Over the past several years, the creative reuse of brownfields has played a major role in Chinese cities to give their urban landscape a so‐called second development. This paper analyses the governance of the brownfield restructuring in Guangzhou (Canton). The research is based on a study of the T.I.T Creative Industry Zone, a highly successful creative space currently in danger of demolition. This paper follows DiGaetano and Strom's ( 2003 ) analytical governance framework. This approach allows for deciphering the complexities of decision‐making through a well‐structured set of interdependent categories. In Guangzhou, new policies and institutions have been promoting the restructuring and have contributed to the formalisation of public–private interactions. In general, this indicates a shift towards a more corporatist governance. However, the study of T.I.T reveals a rather intricate picture: the policymaking remains influenced by a top‐down authoritative style – sometimes in an arbitrary manner – and to some extent also by particularistic exchanges. This indicates a complex mode of urban governance consisting of increasingly corporatist elements but still with managerial, and to a lesser extent, clientelistic elements. Finally, the coexistence of different governance modes seems to be a typical outcome of China's transition while still remaining more adaptive, experimental and flexible in nature.  相似文献   

Computer science funding     

Gries D  Miller R  Ritchie R  Young P 《Science (New York, N.Y.)》1985,230(4722):120

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NDVI-based estimates of evapotranspiration of winter wheat indicate positive effects of N fertilizer application on agronomic water-use efficiency     

Philipp Drerup  Holger Brueck  Dejene Eticha  Heinrich W. Scherer 《Journal of Agronomy and Crop Science》2020,206(1):1-12

Yield increases by fertilizer application impose higher crop water use, as biomass production is positively correlated with transpiration. To quantify effects of N fertilizer supply on evapotranspiration (ET) of winter wheat, a field experiment with three nitrogen rates (N0, N120 and N230) under non-water-limited conditions was performed during 2014 and 2015. Normalized difference vegetation index (NDVI) was used to derive crop coefficients which were used to calculate N effects on bare soil evaporation (E), transpiration, evapotranspiration (ET), grain yield and harvest index (HI). E during the early post-winter growth period was measured with micro-lysimeters and compared with model estimates. N fertilizer supply resulted in lower cumulative E, and increases in grain yield were higher than increases in ET, resulting in a higher agronomic water-use efficiency (WUE_Y). HI of treatment N120 was higher than that of treatment N230 indicating that HI was not the main reason of higher WUE_Y of treatment N230. It is concluded that estimates of ET under variable N supply require consideration of N-induced effects on canopy development which could be successfully monitored by NDVI measurements. N supply increases ET and WUE_Y potentially imposing a trade-off between water conservation and efficiency of water use for crop production.  相似文献   

Genetic diversity of carrot (<Emphasis Type="Italic">Daucus carota</Emphasis> L.) cultivars revealed by analysis of SSR loci     

Rafal Baranski  Anna Maksylewicz-Kaul  Thomas Nothnagel  Pablo F. Cavagnaro  Philipp W. Simon  Dariusz Grzebelus 《Genetic Resources and Crop Evolution》2012,59(2):163-170

Polymorphism of simple sequence repeat (SSR) loci was assessed in a collection of 88 carrot (Daucus carota L. subsp. sativus Hoffm.) accessions. The collection comprised cultivars and landraces mainly from Asia, Europe, and North America. Plants were grown in the glasshouse and characterized for root color and shape. Thirty SSR loci were fully characterized using parameters derived from allele frequencies, i.e. the number of total, effective and rare alleles, the observed and expected heterozygosity, and fixation index. Using a Bayesian approach, two clusters of 17 and 61 accessions were distinguished, which comprised the Asian and Western type accessions, respectively. Genetic diversity of the Asian gene pool was higher than that of the Western gene pool. The results of SSR analysis were supported by morphological characterization, and are congruent with current knowledge on the history of carrot domestication and breeding.  相似文献   

Structural identification of dehydrotriferulic and dehydrotetraferulic acids isolated from insoluble maize bran fiber     

Bunzel M  Ralph J  Brüning P  Steinhart H 《Journal of agricultural and food chemistry》2006,54(17):6409-6418

Two new dehydrotriferulic acids and two dehydrotetraferulic acids were isolated from saponified maize bran insoluble fiber using size exclusion chromatography on Bio-Beads S-X3 followed by Sephadex LH-20 chromatography and semipreparative phenyl-hexyl reversed phase high-performance liquid chromatography. On the basis of UV spectroscopy, mass spectrometry, and one- and two-dimensional NMR experiments, the structures were identified as 8-5(noncyclic)/5-5-dehydrotriferulic acid, 8-8(tetrahydrofuran)/5-5-dehydrotriferulic acid, and 4-O-8/5-5/8-O-4-dehydrotetraferulic acid. The second tetramer was tentatively identified as 4-O-8/5-5/8-5(noncyclic)-dehydrotetraferulic acid. Compounds containing an 8-5(noncyclic)-coupled dimeric unit probably do not exist in planta but are formed from their phenylcoumaran precursors containing an 8-5(cyclic)-coupled dimeric unit during saponification. The presented dehydrotrimers are the first dehydrotriferulates that do not contain an 8-O-4-coupled dimeric unit. The ferulate dehydrotetramers that are reported for the first time are presumed, like the dimers and trimers, to cross-link polysaccharides in the plant. Because both tetramers contain a 5-5/8-O-4-dehydrotriferulate moiety, the predominant dehydrotrimer in maize bran, it is not possible to deduce whether tetramers are formed by coupling of a fourth unit to a preformed dehydrotriferulate or by 5-5-coupling of preformed 8-O-4- and 8-5-dehydrodiferulates. Nevertheless, such compounds document expanded roles for ferulates in cross-linking polysaccharides in plant cell walls.  相似文献   

Effects of electrostimulated acupuncture on ground reaction forces and pain scores in dogs with chronic elbow joint arthritis     

Kapatkin AS  Tomasic M  Beech J  Meadows C  Boston RC  Mayhew PD  Powers MY  Smith GK 《Journal of the American Veterinary Medical Association》2006,228(9):1350-1354

OBJECTIVE: To determine whether use of electrostimuluated acupuncture (ESA) would result in significant improvements in ground reaction forces and lameness scores in dogs with chronic elbow joint osteoarthritis secondary to elbow joint dysplasia. DESIGN: Randomized, controlled, crossover clinical trial. ANIMALS: 9 dogs with chronic forelimb lameness and radiographic evidence of elbow joint osteoarthritis. PROCEDURES: All dogs had a 3-week control acclimation period during which gait analysis was performed weekly. Dogs then received ESA once weekly for 3 weeks followed by a sham treatment once weekly for 3 weeks or received the sham treatment followed by ESA. Gait analysis was repeated prior to each treatment, and owners were asked to provide pain scores by use of a visual analog scale method. RESULTS: Treatment (control, acupuncture, or sham) did not have a significant effect on ground reaction forces for any limb. Owners of 8 of the 9 dogs were able to correctly guess the time period when ESA was delivered. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that ESA did not have any significant effects on severity of lameness, as determined by measurement of ground reaction forces, or severity of pain, as determined by visual analog scale pain scores, in dogs with chronic elbow joint osteoarthritis secondary to elbow joint dysplasia.  相似文献   

Population density and feeding duration of cabbage looper larvae on tomato plants alter the levels of plant volatile emissions     

Miresmailli S  Gries R  Gries G  Zamar RH  Isman MB 《Pest management science》2012,68(1):101-107

BACKGROUND: As part of their indirect defense, plants under herbivore attack release volatile chemicals that attract natural enemies of the herbivore. This is a very well-documented phenomenon. However, relatively few studies have investigated the response of plants to different population levels of herbivores and their feeding duration. RESULTS: Working with larvae of the cabbage looper, Trichoplusia ni (Hübner), and tomato plants, Lycopersicon esculentum Mill cv. clarence, and using an ultrafast gas chromatograph (the zNose™) for volatile analyses, the authors studied the effect of larval density and feeding duration on levels of plant volatile emissions. Intense herbivory caused higher emission levels of the herbivore-induced plant volatiles (HIPVs) (Z)-3-hexenyl acetate, (E)-β-ocimene and β-caryophyllene than those caused by moderate herbivory. When herbivory had ceased following 12–24 h of larval feeding, plants kept releasing HIPVs at a high level for a longer period of time than they did following only 6 h of larval feeding. The plants' slow adjustment in their volatile emissions following prolonged larval feeding might be strategic, as such feeding is more likely to have ceased just temporarily. CONCLUSION: This information may help in the development of a pest monitoring system that is based on herbivore-induced plant volatiles. Copyright © 2011 Society of Chemical Industry  相似文献   

    

R. Philipp 《Forstwissenschaftliches Centralblatt》1895,17(2):117-120

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