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311.
Let L be a very ample line bundle on a smooth complex projective surface. The relations between the higher order embedding properties of L, like k - spannedness, k - very ampleness, k - jet ampleness, and the higher numerical connectedness properties of divisors D ε |L| are Investigated. Some applications to adjoint bundles as well as pluricanonical bundles are discussed. 相似文献
312.
Dalila Rocco Lucinda K. Batchelor Gabriele Agonigi Simona Braccini Federica Chiellini Silvia Schoch Tarita Biver Tiziana Funaioli Stefano Zacchini Lorenzo Biancalana Marina Ruggeri Guido Pampaloni Paul J. Dyson Fabio Marchetti 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(65):14801-14816
Invited for the cover of this issue is the group of Fabio Marchetti at the Università di Pisa and Paul J. Dyson at Ecole Polytechnique Fédérale de Lausanne (EPFL). Read the full text of the article at 10.1002/chem.201902885 . 相似文献
313.
Dalila Rocco Dr. Lucinda K. Batchelor Dr. Gabriele Agonigi Simona Braccini Prof. Federica Chiellini Silvia Schoch Dr. Tarita Biver Dr. Tiziana Funaioli Prof. Stefano Zacchini Dr. Lorenzo Biancalana Marina Ruggeri Prof. Guido Pampaloni Prof. Paul J. Dyson Prof. Fabio Marchetti 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(65):14735-14735
314.
315.
Dalila Rocco Natalia Busto Cristina Pérez-Arnaiz Lorenzo Biancalana Stefano Zacchini Guido Pampaloni Begoña Garcia Fabio Marchetti 《应用有机金属化学》2020,34(11):e5923
A series of diiron complexes with two cyclopentadienyls, two carbonyls, and one bridging vinyl-aminoalkylidene as ligands, [ 3a – h ]CF3SO3 and [ 4a – d ]CF3SO3, was synthesized in 66–94% yields from diiron μ-aminocarbyne precursors. The subsequent reactions with pyrrolidine led to selective fragmentation to aminoalkylidene-ferracyclopentenone derivatives ( 5a – h and 6a – c ) in 30–84% yields. The compounds were characterized by elemental analysis, Fourier transform infrared and NMR spectroscopy, and by single crystal X-ray diffraction in three cases. The stability in aqueous media relevant to biological trials, the carbon monoxide release, and the catalytic activity in NADH oxidation were evaluated for selected compounds by NMR spectroscopy and gas chromatography. The in vitro antiproliferative activity of the compounds was determined towards cancer (A2780, A2780cisR) and noncancer (HEK-293) cell lines. Moreover, the antibacterial activity was tested on Gram-positive (vancomycin-resistant E. faecium and methicillin-resistant S. aureus) and Gram-negative strains (A. baumannii and P. aeruginosa). 相似文献
316.
Aitor Ortega-Martínez Rocco de Lorenzo José M. Sansano Carmen Nájera 《Tetrahedron》2018,74(2):253-259
The Pd-catalyzed allylation of 3-acetyl-2-oxindoles with allyl alcohol is performed using 3 mol% of Pd(dba)2, rac-BINAP and BINOL phosphoric acid as catalytic mixture. This procedure allows the in situ synthesis of 3-allyl-2-oxindole by adding Triton B to the reaction mixture. The deacylative allylation of 3-acetyl-3-methyl-2-oxindoles with allylic alcohols is carried out with 3 mol% of Pd(OAc)2, dppp and 1.5 equiv. of LiOtBu as base affording the corresponding 3,3-disubstituted 2-oxindoles in good yields. Both methodologies can be combined for the preparation of unsymmetrical 3,3-diallylated 2-oxindoles such as compound 7. The DaA must be carried out in the absence of oxygen in order to avoid the competitive formation of 3-alkyl-3-hydroxy-2-indoles. The later compounds can be easily obtained by deacylative oxidation of 3-alkylated 3-acetyl-2-oxindoles with LiOEt at rt under air. 相似文献
317.
Siani AM Casale GR Sisto R Borra M Kimlin MG Lang CA Colosimo A 《Photochemistry and photobiology》2009,85(1):171-177
The aim of this study was to investigate whether systematic differences in solar UV exposure on a specific anatomical site (chest) exist among three groups of Italian sunbathers: healthy subjects (suntanned and non-suntanned individuals) and subjects affected by abnormally high sensitivity to solar exposure. A second aim of the study was to search for a possible relation among biological markers of individual response to UV exposure (such as skin colorimetric parameters, skin temperature and changes in free radical amounts [FR] in the blood) and photosensitivity. FR in the blood were analyzed because of their possible influence on UV carcinogenesis. Measurements of ambient doses (i.e. incident erythemally weighted irradiance on a horizontal surface over a specified period of time) and erythemally effective UV dose received by an anatomical site (here called personal dose or exposure on a specific anatomical site) were investigated. Personal doses received by the chest were determined using polysulfone dosimetry. Exposure Ratio (ER), defined as the ratio between the personal dose and the corresponding ambient dose during the same exposure period, was then calculated. Measuring of skin color in the Commission Internationale de l'Eclairage L (luminance), a (redness), b (yellowness) system and skin temperature were also carried out on the inner upper arm (nonexposed skin site) and on the chest. It was found that the median value of ER was 0.20 (min: 0.09 and max: 0.34) for suntanned individuals, it was 0.17 (min: 0.13 and max: 0.42) for non-suntanned individuals and it was 0.19 (min: 0.14 and max: 0.34) for photosensitive individuals. There were no significant differences across the groups in their median ER scores. In addition, the statistical analysis showed that L on the exposed site before exposure demonstrated consistently higher median scores after exposure in all groups. The b value after exposure was significantly lower than before exposure in all participants, while no significant differences for a were observed before or after exposure between or within the groups. Our findings suggest that photodermatoses are not significantly related to ER and to the changes in biological markers due to too short-term UV exposure. 相似文献
318.
Antonio Ranieri Marco Borsari Stefano Casalini Giulia Di Rocco Marco Sola Carlo Augusto Bortolotti Gianantonio Battistuzzi 《Molecules (Basel, Switzerland)》2021,26(16)
Cytochrome c is a small globular protein whose main physiological role is to shuttle electrons within the mitochondrial electron transport chain. This protein has been widely investigated, especially as a paradigmatic system for understanding the fundamental aspects of biological electron transfer and protein folding. Nevertheless, cytochrome c can also be endowed with a non-native catalytic activity and be immobilized on an electrode surface for the development of third generation biosensors. Here, an overview is offered of the most significant examples of such a functional transformation, carried out by either point mutation(s) or controlled unfolding. The latter can be induced chemically or upon protein immobilization on hydrophobic self-assembled monolayers. We critically discuss the potential held by these systems as core constituents of amperometric biosensors, along with the issues that need to be addressed to optimize their applicability and response. 相似文献
319.
320.
AbstractIn this survey, we consider the classical overdetermined problem which was studied by Serrin in 1971. The original proof relies on Alexandrov’s moving plane method, maximum principles, and a refinement of Hopf’s boundary point Lemma. Since then other approaches to the same problem have been devised. Among them we consider the one due to Weinberger which strikes for the elementary arguments used and became very popular. Then we discuss also a duality approach involving harmonic functions, a shape derivative approach and a purely integral approach, all of them not relying on maximum principle. For each one, we consider pros and cons as well as some generalizations. 相似文献