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51.
Zheng, D., Zhang, Q., Nel, A., Jarzembowski, E.A., Zhou, Z., Chang, S.-C. &; Wang, B., May 2016. New damselflies (Odonata: Zygoptera: Hemiphlebiidae, Dysagrionidae) from mid-Cretaceous Burmese amber. Alcheringa XX, xxx–xxx. ISSN 0311-5518

Two damselflies, Burmahemiphlebia zhangi gen. et sp. nov. and Palaeodysagrion cretacicus gen. et sp. nov., are described from the mid-Cretaceous Burmese amber. Burmahemiphlebia zhangi is the first record of Hemiphlebiidae from this amber, although the family was cosmopolitan during the Mesozoic. It can be readily distinguished from all other members of Hemiphlebiidae in having very short MP and CuA veins, and in its rectangular discoidal cell. The new fossils support the view that hemiphlebiid damselflies were one of the dominant groups of Zygoptera during the Mesozoic. Palaeodysagrion cretacicus is the first dysagrionid damselfly from Burmese amber and the second Mesozoic representative of this predominantly Paleogene group. It differs from other members of Dysagrionidae in having a unique elongate discoidal cell. These new finds increase the diversity of damselflies in mid-Cretaceous Burmese amber.

Daran Zheng* [], Su-Chin Chang [], Department of Earth Sciences, The University of Hong Kong, Hong Kong Special Administrative Region, PR China; Qingqing Zhang [], Edmund A. Jarzembowski? [], Bo Wang? [], State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 39 East Beijing Road, Nanjing 210008, PR China; André Nel [], Institut de Systématique, Évolution, Biodiversité, ISYEB-UMR 7205-CNRS, MNHN, UPMC, EPHE, Muséum national d’Histoire naturelle, Sorbonne Universités, 57 rue Cuvier, CP 50, Entomologie, F-75005, Paris, France; Zhicheng Zhou [], The PLA Information Engineering University, 62 Kexue Ave, Gaoxin District, Zhengzhou 450002, Henan, PR China. *Also affiliated with State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 39 East Beijing Road, Nanjing 210008, PR China. ?Also affiliated with Department of Earth Sciences, The Natural History Museum, London SW7 5BD, UK. ?Also affiliated with Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, PR China.  相似文献   
52.
HUANG D. & NEL A., June 2017. New fossil damsel -dragonfly clarifies the phylogenetic position of the small Jurassic family Juraheterophlebiidae (Odonata: Epiproctophora). Alcheringa, 41, 536–542.

A nearly complete specimen of Juraheterophlebia cancellosa sp. nov., the third species of the family Juraheterophlebiidae, is described from the Middle–Late Jurassic of China and shows the exact structure of its forewing discoidal space. As a consequence, this family is restored, separated from Erichschmidtiidae, and its diagnosis amended. It is transferred from Heterophlebioptera to Stenophlebioptera, the first clade being now only known from the Early Jurassic. Erichschmidtiidae includes the sole species Erichschmidtia nigrimontana, and this family is now considered of uncertain systematic position.

Diying Huang [] State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210,008, PR China; André Nel [] Institut de Systématique, Évolution, Biodiversité, ISYEB-UMR 7205-CNRS, MNHN, UPMC, EPHE, Muséum national d’Histoire naturelle, Sorbonne Universités, 57 rue Cuvier, CP 50, Entomologie F-75005, Paris, France.  相似文献   

53.
Abstract

The aim of this article is to shed some light on issues of territorial development and of rural development and to identify what links and opposes them. Indeed, everything pushes towards joining these two dimensions, which for a long time seemed disconnected. On the one hand, the policies targeting rural areas explicitly include the territorial dimension, while the distinction between rural and urban is getting blurred. In the meantime, decentralization, subsidiarity, the regionalization of agriculture, short circuits and local foods take place in parallel with the generalization of an urban model. Finally, we find that regional sciences are paying increasing attention to rural and agricultural dimensions, while studies concerning rural questions are starting to consider territorial issues. The first section of the article provides a critical presentation and attempts to define and distinguish the notions of development, territory and the rural. The second section addresses questions of regional and territorial development by presenting the main theories and public policies and concludes with a discussion about the possibilities of reconciling the theories and the policies. The third section follows the same structure, applied to the question of rural development, from analyses to grass-roots policies.  相似文献   
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Calcium oxalate patinas have been sampled on architectural elements of two ancient churches located on Torcello Island (Venetian Lagoon) and subsequently analyzed. The site had been selected presenting patinas of exceptional amount and thickness, elsewhere generally found as thin alteration layers covering stone surfaces or within black crusts on monuments in urban environments. Optical and mineralogical analyses suggest that these patinas are not the result of a simple deposition process, but originate as surface “transformations” of the substrate, and are mainly composed of dihydrate calcium oxalate (weddellite) and gypsum. Among the experimental techniques, isotope analyses (C and S) have been specifically carried out aiming at achieving a better understanding of their origin and possible causes of formation. The observed carbon isotopic fingerprint reveals in fact a strong biological fractionation recorded in the oxalate patina (δ13C ranging from ?22.3‰ to ?28.0‰), almost exclusively attributable to C3 pathway photosynthesis processes. Slightly negative sulfur isotope ratio values seem to be inversely correlated with patina exposure to atmospheric agents and pollutants. The results obtained prove that calcium oxalate originates from a biomineralization process induced by lichen colonization in specific environmental conditions.  相似文献   
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A painted monolith, as important as the Aztec Calendar or the Coyolxauhqui, has been discovered in the ritual Aztec center of Mexico City. It represents Tlaltecuhtli, the bisexual manifestation of the Earth from whom all life comes. Still, pigments, which have lost their conglomerating resins, have to be retained. In this study, the consolidation of ochre pigment on original fragments from the Aztec sculpture is presented. Several compounds were tested as consolidants, on the one hand natural polysaccharides, Funori and Slobber of Nopal exudate, on the other derivatives of cellulose, Methocel® and Klucel®, and also commercial consolidants as KSE 300® and Paraloid B72®. To simulate the ageing of consolidated samples, they were treated in an Accelerated Weathering Tester. Then, both sets of samples, fresh and aged, were characterized structural, morphological and texturally by using X-ray diffraction, electronic microscopy and nitrogen adsorption, respectively. A leaching test was performed on consolidated samples to evaluate the consolidant efficiency.  相似文献   
60.
In this paper the results of use-wear analysis of an Amudian lithic assemblage recently discovered at Qesem Cave, Israel, are presented. Although very old, this assemblage maintains well-preserved traces of use that indicate that butchering activities and plants collecting were carried out at the site. Cut marks on faunal remains confirm the observations obtained by use-wear analysis.  相似文献   
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