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排序方式: 共有1543条查询结果,搜索用时 31 毫秒
211.
Gastón Gutiérrez-Gamboa Eva P. Pérez-Álvarez Pilar Rubio-Bretón Teresa Garde-Cerdán 《International Journal of Food Science & Technology》2019,54(4):1160-1168
Edible mushrooms production presents a potential problem for the environment, due to the large amount of waste generated. These wastes contain nitrogenous matter, which could be used as biostimulant in plants. The aim of this work was to study the effect of waste waters, from the mushroom production process, applied at veraison and 1 week later to grapevine leaves, on grape volatile compounds over two vintages. The results evidenced that mushroom water treatment decreased the grape content of certain terpenoids, C13 norisoprenoids, benzenoid compounds and esters, increasing C6 compounds content during the first season. Treated mushroom water application slightly affected grape volatile composition. This was the treatment that least affected the content of grape volatile composition. Few differences were found after the biostimulation during the second vintage. The season was the dominant factor of grape volatile content variation compared to the treatment and their interaction. 相似文献
212.
Pattern Analysis and Applications - In robotic systems, both software and hardware components are equally important. However, scant attention has been devoted until now in order to detect... 相似文献
213.
214.
Annexin homologues in the kingdoms of Planta and Protista were characterized by molecular sequence analysis to determine their phylogenetic and structural relationship with annexins of Animalia. Sequence fragments from 19 plant annexins were identified in sequence databases and composite sequences were also assembled from expressed sequence tags for Arabidopsis thaliana. Length differences in protein aminotermini and evidence for unique exon splice sites indicated that plant annexins were distinct from those of animals. A third annexin gene of Giardia lamblia (Anx21-Gla) was identified as a distant relative to other protist annexins and to those of higher eukaryotes, thus providing a suitable outgroup for evolutionary reconstruction of the family tree. Rooted evolutionary trees portrayed protist, plant, and Dictyostelium annexins as early, monophyletic ramifications prior to the appearance of closely related animal annexin XIII. Molecular phylogenetic analyses of DNA and protein sequence alignments revealed at least seven separate plant subfamilies, represented by Anx18 (alfalfa, previously classified), Anx22 (thale cress), Anx23 (thale cress, cotton, rape and cabbage), Anx24 (bell pepper and tomato p34), Anx25 (strawberry, horseradish, pea, soybean, and castor bean), Anx26-Zma, and Anx27-Zma (maize). Other unique subfamilies may exist for rice, tomato p35, apple, and celery annexins. Consensus sequences compiled for each eukaryotic kingdom showed some breakdown of the "annexin-fold" motif in repeats 2 and 3 of protist and plant annexins and a conserved codon deletion in repeat 3 of plants. The characterization of distinct annexin genes in plants and protists reflects their comparable diversity among animal species and offers alternative models for the comparative study of structure-function relationships within this important gene family. 相似文献
215.
This work compares the tectal codification of eye movements in goldfish with those reported for other vertebrate groups. Focal electrical stimulation was applied in various tectal zones and the characteristics of evoked eye movements were examined as a function of (i) the position of the stimulation over the tectal surface, (ii) the initial position of the eyes and (iii) the parameters (pulse rate, current strength, duration) of the stimulus. In a large medial zone, stimulation within the intermediate and deep layers of the tectum evoked contraversive saccades of both eyes, whose direction and amplitude were roughly congruent with the retinotopic representation of the visual world within overlying layers. These saccades were minimally influenced by the initial position of the eye in the orbit. The topographical arrangement of evoked saccades and body movements suggests that this tectal zone triggers orienting responses in a similar way to those described in other vertebrates. Stimulations applied within the caudal tectum also evoked contraversive saccades, but in disagreement with the overlying retinotopic map--the vertical component was absent. Taken together with electrically evoked body movements reported in free-swimming fish, these saccades could reveal that this zone is involved in escape responses. When stimulations were applied within the anteromedial zone of the tectum, contraversive movements of both eyes appeared much more dependent on initial eye position. Saccades elicited from this area displayed characteristics of "goal-directed saccades" which were similar to those described in the cat. The generation of goal-directed movements from the anteromedial zone suggests that this portion of the goldfish optic tectum has a different intrinsic organization or is connected with the brainstem saccade generator in a different fashion than the medial zone. Finally, stimulation of the extreme anteromedial zone evoked convergent eye movements. These movements and those reported in free-swimming fish following electrical stimulation of this tectal area suggest that this zone could be involved in feeding responses. The relationships between the parameters of electrical stimulation and the characteristics of elicited saccades suggest that the stimulated location within the tectum determines a constant direction in the evoked saccade, whereas the amount and duration of tectal activity, as mimicked by changes in stimulus parameters, together with the tectal locus, determine the velocity and amplitude of the evoked saccade. 相似文献
216.
Noelia Maldonado Vernica G. Vegas Oded Halevi Jose Ignacio Martínez Pooi See Lee Shlomo Magdassi Michael T. Wharmby Ana E. Platero‐Prats Consuelo Moreno Flix Zamora Pilar Amo‐Ochoa 《Advanced functional materials》2019,29(15)
This work presents the fabrication of 3D‐printed composite objects based on copper(II) 1D coordination polymer ( CP1 ) decorated with thymine along its chains with potential utility as an environmental humidity sensor and as a water sensor in organic solvents. This new composite object has a remarkable sensitivity, ranging from 0.3% to 4% of water in organic solvents. The sensing capacity is related to the structural transformation due to the loss of water molecules that CP1 undergoes with temperature or by solvent molecules' competition, which induces significant change in color simultaneously. The CP1 and 3D printed materials are stable in air over 1 year and also at biological pHs (5–7), therefore suggesting potential applications as robust colorimetric sensors. These results open the door to generate a family of new 3D printed materials based on the integration of multifunctional coordination polymers with organic polymers. 相似文献
217.
To the best of our knowledge, there is no work that has focused on analysing the development of the scientific production on women, peace and security. The main objective of this paper is to cover this research gap through a bibliometric analysis, that covers 95 years (1918–2013), of articles published in peer-reviewed journals extracted from the SCOPUS database. Bibliometric indicators and laws have been applied to better understand the patterns that govern the scientific literature on this realm. A gender perspective has also been implemented in the analysis. The analysis provides quantitative results based on 321 articles published by 478 authors in 210 scientific journals. The data showed the high dispersion of the literature, both in terms of authors and journals focused on the topic, and a low level of collaboration among both authors and institutions. Regarding the research topic, half of the papers were related to the impact of conflict on civilians and civil society. The implementation of a gender perspective shows that most of the first, second and third authors of the papers are women. In terms of methodologies, qualitative methodologies are the most relevant and women are more prolific applying these methodology. In terms of geographical region of the research, most of the studies have been performed by authors from institutions in Anglo-Saxon countries, and most of the fieldwork has been focused on the United States and the main areas of conflict in the world throughout history. Finally, important research opportunities are identified. 相似文献
218.
Fabrication of Highly Porous Mullite Materials 总被引:1,自引:0,他引:1
Rafael Barea Maria I. Osendi Pilar Miranzo José M. F. Ferreira 《Journal of the American Ceramic Society》2005,88(3):777-779
Porous mullite, formed by large spherical-shaped pores evenly distributed within a mullite matrix, was processed by a direct consolidation method based on the starch swelling properties. Materials with porosities up to 60 vol% and with an average pore size of ∼30 μm were prepared. Porosity matched the starch volume fraction for contents ≥45 vol%, while for lower contents the porosity was above the volume fraction of starch. Formation of crack like defects either surrounding or connecting pores occurred during the drying–sintering processes in the high starch content mullite. 相似文献
219.
John M. Hutchinson Salvador Montserrat Frida Romn Pilar Corts Lourdes Campos 《应用聚合物科学杂志》2006,102(4):3751-3763
Various methods of preparation of epoxy resin/clay mixtures, before the addition of the crosslinking agent and curing to form epoxy‐based polymer layered silicate (PLS) nanocomposites, have been investigated to determine their effect on the nanostructure. Organically modified montmorillonite clay was used, and the mixtures were prepared by both simple mixing and solvent‐based methods. X‐ray diffraction shows that intercalation of the resin into the clay galleries occurs for all clay loadings up to 25 wt % and for both preparation methods, but the dispersion of the clay in the resin, observed by optical microscopy, is significantly better for the solvent preparation method. Differential scanning calorimetry (DSC) shows that the intercalated resin has the same molecular mobility as the extra‐gallery resin, but suggests that the intercalated resin does not penetrate completely into the galleries. Prolonged storage of the resin/clay mixtures at room temperature leads to changes in the DSC response, as well as in the response to thermogravimetry, which are interpreted as resulting from homopolymerization of the epoxy resin, catalyzed by the onium ion in the modified clay. This confirms and explains the earlier observation of Benson Tolle and Anderson (J Appl Polym Sci 2004, 91, 89) that “conditioning” of the resin/clay mixtures at ambient temperature has a significant effect when the crosslinking agent is subsequently added, and indicates that the preparation method has important consequences for the nanostructure development in the PLS nanocomposites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:3751–3763, 2006 相似文献
220.
Wirtz T Fleming Y Gerard M Gysin U Glatzel T Meyer E Wegmann U Maier U Odriozola AH Uehli D 《The Review of scientific instruments》2012,83(6):063702
State-of-the-art secondary ion mass spectrometry (SIMS) instruments allow producing 3D chemical mappings with excellent sensitivity and spatial resolution. Several important artifacts however arise from the fact that SIMS 3D mapping does not take into account the surface topography of the sample. In order to correct these artifacts, we have integrated a specially developed scanning probe microscopy (SPM) system into a commercial Cameca NanoSIMS 50 instrument. This new SPM module, which was designed as a DN200CF flange-mounted bolt-on accessory, includes a new high-precision sample stage, a scanner with a range of 100 μm in x and y direction, and a dedicated SPM head which can be operated in the atomic force microscopy (AFM) and Kelvin probe force microscopy modes. Topographical information gained from AFM measurements taken before, during, and after SIMS analysis as well as the SIMS data are automatically compiled into an accurate 3D reconstruction using the software program "SARINA," which was developed for this first combined SIMS-SPM instrument. The achievable lateral resolutions are 6 nm in the SPM mode and 45 nm in the SIMS mode. Elemental 3D images obtained with our integrated SIMS-SPM instrument on Al/Cu and polystyrene/poly(methyl methacrylate) samples demonstrate the advantages of the combined SIMS-SPM approach. 相似文献