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1.
The present paper, mainly dealing with phytogeographical, Cytological and Palynolo gical studies on Chinese Stachyuraceae, is the first part of a series of contributions to systematics of this family. As we know, Stachyuraceae, a monogeneric family, is endemic to East Asia, with a strong differentiation in China. Systematic position of the family is still uncertain. Undoubtedly, multidisciplinary studies on it wisl give a better understanding of plant differentiation in East-Asiatic floristic region and systematic position of the family. The distribution of all the 9 Chinese species of Stachyurus have been studied on the basis of morphogeographical method. The status of some taxa has been changed as follows: Stachyurus chinensis Franch. ssp. latus (Li) Y. C. Tang et Y. L. Cao, stat. nov. S. chinen-sis Franch. Ssp. cuspidatus (Li) Y. C. Tang et Y. L. Cao, stat. nov. S. chinensis Franch. ssp. brachystachyus (C. Y. Wu et S. K. Chen) Y. C. Tang et Y. L. Cao, stat. nov. S. salicifolius Franch. ssp. lancifolius (C. Y. Wu) Y. C. Tang et Y. L. Cao, stat. nov., S. yunnanensis Franch. var. pedicellatus Rehd. and S. oblongifolius Wang et Tang being reduced as synonyms of S. yunnanensis Franch. From morphological point of view, we would consider that sect. Callosurus is more primitive and its present area might be the preservation center of the family. In this paper the chromosome numbers of 5 taxa, i.e. Stachyurus yunnanensis, S. chinensis ssp. chinensis, S. chinensis ssp. cuspidatus, S. salicifolius ssp. salicifolius, S. retusus, are reported for the first time. Along with the chromosome countings of S. himalaicus and S. sigeyosii by S. kurosawa, we come to the conclusion that all the species so far studied have 24 small somatic chromosomes (2n=24). The pollen grains of 6 taxa, i.e. Stachyurus yunnanensis, S. obovatus, S. himalaicus, S. chinensis ssp. chinensis, S. salicifolius ssp. salicifolius, S. retusus were also examined. Together with the observations of G. Erdman and Huang Tsengchien on S. himalaicus, it seems that the pollen grains of the genus Stachyurus are rather uniform in morphology. The pollen grains of sect. Callosurus are tricolporoidate, while those of sect. Stachyurusare tricolporate. Two pollen types, representeb by the two sections, though not strongly distinct, may be considered as further evidence of the validity of the two taxa as section. Sexuality of flowers is also disscussed in the paper. According to our observationon six species, i.e. Stachyurus yunnanensis, S. obovatus, S. himalaicus, S. chinensis, S. salicifolius, S. retusus, the plants are dioecious, which supports T. Makino's observation on S. praecox and H. Hara's on S. himalaicus. Female flowers have relatively large pistils and short stamens with empty anthers, while male flowers have smaller sterile pistils and longer stamens with well developed anthers. Decontaminated thianthrene disproportion. 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Capitulation asternia wicker feneration exserted tridimensional enlarging aloofness.  相似文献   

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Several attributes of the work schedule can increase the risk of occupational injuries and accidents, health impairments, and reduced social participation. Although previous studies mainly focused on the effects of shiftwork and long working hours on employee health and safety, there is little evidence of a potential negative impact of working Sundays on the incidence of occupational accidents, health impairments, and work-life balance. A representative sample of employed workers in 31 member and associated states of the European Union (n?=?23,934) served as the database for a cross-sectional analysis. The sample was collected via face-to-face interviews in the year 2005. The association of the risks of occupational accidents, health impairments, and decreases in work-life balance with working Sundays was calculated using logistic regression models, controlling for potential confounders, such as shiftwork, workload, and demographic characteristics. The results indicated that working one or more Sundays/month was associated with increase both in the risk of reporting one or more health impairments (odds ratio [OR]: 1.17, 95% confidence interval [CI]: 1.06-1.29) and poorer work-life balance (OR: 1.15, 95% CI: 1.02-1.28). These effects remained after controlling for potentially confounding factors, such as other work schedule attributes, intensity of physical and mental workload, and individual characteristics. Furthermore, working Sundays was also related to increased risk of occupational accidents within the last year (OR: 1.34, 95% CI: 1.03-1.73). Controlling again for individual, workload, and working-time characteristics, a significant association with accident risk, however, remained only in work sectors with low a priori risk of occupational accidents (OR: 1.40, 95% CI: 1.02-1.91), although the increased risk could be observed for both medium and high a priori risk sectors working Sundays (without controlling for additional confounders). The results thus indicate that the detrimental effects of working Sundays on safety, health, and social well-being should be taken into account when designing work schedules. The potential hazards to employees' safety, health, and work-life balance, in particular, should be considered in discussions concerning extending work on Sundays in certain sectors, e.g., retail.  相似文献   

3.
Several attributes of the work schedule can increase the risk of occupational injuries and accidents, health impairments, and reduced social participation. Although previous studies mainly focused on the effects of shiftwork and long working hours on employee health and safety, there is little evidence of a potential negative impact of working Sundays on the incidence of occupational accidents, health impairments, and work-life balance. A representative sample of employed workers in 31 member and associated states of the European Union (n?=?23,934) served as the database for a cross-sectional analysis. The sample was collected via face-to-face interviews in the year 2005. The association of the risks of occupational accidents, health impairments, and decreases in work-life balance with working Sundays was calculated using logistic regression models, controlling for potential confounders, such as shiftwork, workload, and demographic characteristics. The results indicated that working one or more Sundays/month was associated with increase both in the risk of reporting one or more health impairments (odds ratio [OR]: 1.17, 95% confidence interval [CI]: 1.06–1.29) and poorer work-life balance (OR: 1.15, 95% CI: 1.02–1.28). These effects remained after controlling for potentially confounding factors, such as other work schedule attributes, intensity of physical and mental workload, and individual characteristics. Furthermore, working Sundays was also related to increased risk of occupational accidents within the last year (OR: 1.34, 95% CI: 1.03–1.73). Controlling again for individual, workload, and working-time characteristics, a significant association with accident risk, however, remained only in work sectors with low a priori risk of occupational accidents (OR: 1.40, 95% CI: 1.02–1.91), although the increased risk could be observed for both medium and high a priori risk sectors working Sundays (without controlling for additional confounders). The results thus indicate that the detrimental effects of working Sundays on safety, health, and social well-being should be taken into account when designing work schedules. The potential hazards to employees' safety, health, and work-life balance, in particular, should be considered in discussions concerning extending work on Sundays in certain sectors, e.g., retail. (Author correspondence: )  相似文献   

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From January 2010 to December 2011, a total of 138 cases of ticks feeding on humans were reported from 11 locations in central Panama. Five of these locations were situated in forest environments, three in rural landscapes and three in urban areas. The ticks were submitted to the Gorgas Memorial Institute, where nine species were identified among 65 specimens: Amblyomma cajennense s.l., A. dissimile, A. naponense, A. oblongoguttatum, A. ovale, A. sabanerae, A. tapirellum, Haemaphysalis juxtakochi and Rhipicephalus sanguineus s.l. The remaining 73 specimens consisted of unidentified immature ticks, all belonging to the genus of Amblyomma. Rhipicephalus sanguineus s.l. was the species most frequently associated with humans, particularly in urban environments. In rural landscapes, tick bites were most often caused by A. cajennense s.l., whereas A. tapirellum was the species most often found parasitizing humans in forest environments. These data provide information on the tick species most commonly associated with humans in forested environments, rural areas and cities around the Panama Canal.  相似文献   

7.
Valim MP  Weckstein JD 《ZooKeys》2011,(128):1-13
Two new species of Brueelia are described and illustrated. These new species and their type hosts are: Brueelia sueta ex Pharomachrus pavoninus (Spix, 1824), the Pavonine Quetzal and Brueelia cicchinoi ex Trogon viridis Linnaeus, the White-tailed Trogon. Both new species differ from the only Brueelia described on Trogon mexicanus by many morphological features, including those present in the male genitalia and female vulvar margin. Partial sequences of the mitochondrial cytochrome oxidase I (COI) gene for these two new species differ from one another by 13.6% uncorrected p-distance. Whereas Brueelia cicchinoi is only 0.3% divergent from previously published COI sequences identified as Brueelia sp. from the Mexican Trogon melanocephalus Gould, 1936 and Trogon massena Gould, 1938. We also found Brueelia cicchinoi on Trogon melanurus, Trogon collaris and Pharomachrus pavoninus. Thus Brueelia cicchinoi is found on multiple trogoniform hosts across an extremely large geographic distribution and has one of the largest number of host associations among Brueelia species.  相似文献   

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TheSeventhInternationalWorkshoponSeedBiolo gywasheldfrom 1 2to 1 6May ,2 0 0 2inUniversityofSalamanca ,Spain .ThiswasthefirstworkshoptobeheldentirelyundertheInternationalSocietyforSeedScience(ISSS)banner.About 30 0seedscientistsfrom 2 0coun triesattendedthisworkshop .Aftertheopeningceremony ,thepresident_elect,Prof.DerekBewley ,fromGuelphUniversityofCanada ,openedwithastimulatingoverviewofseedsinscienceandsociety ,whichwasentitled“SeedsofHope,SeedsofDespair” .Hereviewedthehis tory…  相似文献   

10.
A survey of aphids was carried out during the period 2008-2011 in different regions of Algeria by collecting and identifying aphids and their host plants. Aphids were collected from 46 host plants. Forty-six species were reported including thirty-six species which were recorded for the first time in this country and thirty species which were recorded for the first time in the Maghreb (North Africa). This study extends the number of known Algerian aphid to 156 species.  相似文献   

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Understanding the genetics of colonizing populations has been, and continues to remain, an important focus in evolutionary biology. Different theoretical models predict varying levels of genetic variation in colonizing populations depending upon strength of founder effect, gene flow and rate of population growth and immigration following colonization. We analyse overall genetic variation using amplified fragment length polymorphism markers in colonizing populations of Hypochaeris tenuifolia (Asteraceae) in the southern Andes. Volcán Lonquimay newly erupted on 25 December 1988, producing a side cone, La Navidad, and sent lava and ash into surrounding areas. Many domesticated animals (estimated at 10 000) and many natural plant populations were destroyed. Into this new open habitat have come immigrant populations of several angiosperm species, most conspicuously H. tenuifolia that forms leaf rosettes with flowering scapes to 15 cm and orange-yellow heads 1-2 cm in diameter. Genetic diversity in five founder populations in the eruption zone is compared with that from five nearby survivor populations, as well as with eight isolated northern and four southern populations from throughout the entire range of the species in Chile. Results from 477 individuals representing 447 different multilocus phenotypes, yielded 170 DNA fragments of which 144 (85%) were polymorphic. Genetic diversity within founder populations is neither lower than in survivor populations nor in isolated populations throughout the range of the species, but it is lower among founder populations than among other populations immediately and distantly outside the zone of disturbance. Closest genetic similarity occurs between founders and nearby survivor populations as well as those in adjacent southern regions.  相似文献   

14.
Climate change is predicted to cause continued increases in global temperatures, greater variability in precipitation and in some cases, more frequent insect pest outbreaks. Here we seek to understand how abiotic and biotic stresses associated with climate change can affect plant-herbivore interactions in a model crop species (soybean, Glycine max (L.) Merr.) by answering three questions: (1) Do the combined effects of abiotic and biotic stresses associated with climate change cause synergistic negative effects on plant biomass? (2) Can abiotic stress affect resistance of plants to insect herbivores? (3) Does genetic variation in plant traits modify a plant’s response to stress? We performed three experiments in controlled growth environments using up to 51 soybean genotypes selected to vary in numerous traits associated with drought and resistance against pests (e.g., insect herbivores, nematodes, and pathogenic fungi), and up to 3 generalist-feeding herbivorous noctuid moth species (Helicoverpa zea, Heliothis virescens, and Spodoptera exigua) that commonly feed on soybean in North America. Drought and herbivory had the largest and the most consistent negative effects on plant performance, reducing the above- and below-ground biomass by 10-45 %, whereas increased temperature had little to no effect on plants. Drought also increased susceptibility to generalist noctuid herbivores, but these results varied dramatically in magnitude and direction among plant genotypes. Our experiments show that the effects of abiotic and biotic stress on soybean biomass were largely due to the additive effects of these stresses, and there exists substantial genetic variation in the soybean germplasm pool we studied that could be used as a source of parental stock in breeding new crops that can more effectively tolerate and resist the combined negative effects of insect herbivory and drought.  相似文献   

15.

From 1994 to 1997 investigations have been carried out on fields of the "Ökohof Seeben" in Halle (Saale), refering to long-term effects of ecological agriculture on fauna, flora and soil. For the sampling of the epigeic fauna, pitfall traps were used. The purpose was to examine the effect of the changes in management on spiders for example. The influence of field size, edge-structures and different crops on species- and individual-numbers was studied. The question was, whether ecological agriculture results in an increasing biodiversity overviewed over years. In 4 years, on 6 fields, 190 species of spiders (82,202 adults spiders) could be proved, among them 32 species endangered in Sachsen-Anhalt and 28 species endangered according to the Red-Data-Books of Germany. The species numbers in the edge-biotops were nearly twice the numbers in the fields. The activity density of pioneer species (for example Oedothorax apicatus ) decreased rapidly on all fields. As a whole species numbers, and also the number of seldom species, were higher on the small fields than on the large fields lying in a poor structured environment. On the large fields some species, especially some Gnaphosidae and Lycosidae were missing in the first two years, but could be proved in the later years. Increasing numbers of species bigger in size and also more balanced dominance structures could be observed in the later years of investigation. In the fields the Linyphiidae species O. apicatus, E. atra, E. dentipalpis, M. rurestris, L. tenuis, P. microphthalmum, A. humilis and the Lycosidae P. agrestis and P. prativaga were dominant. Other species, like D. concolor, B. gracilis, H. signifer, P. juncea, T. ruricola, D. pusillus, X. kochi, O. claveata, P. degeeri, P. palustris, R. lividus prefered the adjacent boundaries, but were represented in the field as well. Several species, such as A. cuneata, A. pulverulenta, T. terricola, X. miniata, X. nemoralis, A. albimana, P. mirabilis, Ch. campestre, X. acerbus, Z. spinimana, P. festivus, D. praeficus and D. lutetianus could be proved only in the adjacent boundaries. Altogether positive effects on the dominance structure of spiders could be shown. An increasing biodiversity may be expected.  相似文献   

16.
The speciesOstorhinchus fleurieu Lacepède, 1802 is recognized as a senior synonym ofApogon aureus (Lacepède, 1802) on the basis of diagnostic colour features of Lacepède’s illustration of the species (after Commerson). The species is redescribed and a neotype designated. The synonymy of the species is discussed in the light of the history of Commerson’s and Lacepède’s work.Nectamia is replaced byOstorhinchus as a subgenus ofApogon.  相似文献   

17.
A new species of Harmonicon F. O. Pickard-Cambridge, 1896 (Araneae, Dipluridae) is described, from a medium-sized lateritic cave in Parauapebas, Pará, Brazil. The male holotype and only specimen known of H. cerberus sp. n. was found near the entrance of Pequiá cave. This taxon is the fourth species described and the southernmost record for the genus. The new species displays some troglomorphic characteristics, such as reduction and merging of the posterior median and both pairs of lateral eyes and pale yellow to light brown coloration. Both characters are diagnostic when compared to the normal separated eyes and reddish to dark brown of other Harmonicon species. Other diagnostic characteristics are isolated, long, rigid setae distal to the lyra and the shape of the copulatory bulb. This is the second troglomorphic mygalomorph species from Brazil and the first from the Amazonian region.  相似文献   

18.
19.
Résumé Les larves de deux espèces deSystoechus (somali oldroyd etaurifacies greathead), attaquent les œufs du criquet pèlerin (Schistocerca gregaria Forsk?l) en Afrique orientale. La morphologie des larves et des pupes de ces deux espèces et de deux autres a été étudiée en détail. Les larves sont presque identiques; seulement quelques faibles différences ont été observées dans la forme des sclérites céphaliques. Les pupes, d'autre part, présentent des caractères plus distincts. La distribution duSystoechus parmi les lieux d'oviposition duSchistocerca et parmi les oothèques d'une même station est très irrégulière. Chaque larve demande 8–10 œufs (c'est-à-dire un huitième d'une oothèque) pour le développement complet. On trouve souvent plus d'une larve dans l'oothèque, mais il n'en résulte pas la destruction de tous les œufs. Le développement larvaire et le stade de pupe durent chacun à peu près une semaine, mais la larve développée passe dans le sol une période de repos dont la durée varie de plusieurs mois à plusieurs années. Les pluies déclenchent la formation des pupes; toutes les larves ne se transforment pas à la première pluie; en conséquence, l'éclosion des adultes est très échelonnée.   相似文献   

20.
On the occasion of the XIIIth International Symposium on Spermatology held from 9 to 13 May 2018 in Stockholm (Sweden), participants (guest speakers and audience) collectively felt the need to make a public statement on the general issue of male reproductive health. Our intention is to raise awareness of what we believe is a neglected area of research despite alarming situations around the world. The disclosure strategy desired by the co-authors is to bring it to the attention of the greatest number partly by considering co-publication in the various periodicals dealing with Reproductive Biology and Andrology. BaCA’s editorial office accepted this mission and found it natural that our periodical, the official journal of the French Andrology Society (SALF), should carry this message.  相似文献   

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