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41.
Mezzetti E. Colombo S. Gerbaldo R. Ghigo G. Gozzelino L. Minetti B. Cherubini R. Abbattista F. Ronchetti S. Vallino M. 《Il Nuovo Cimento D》1994,16(10):1933-1939
Il Nuovo Cimento D - Bulk slabs of sintered YBCO were irradiated with monoenergetic protons at different energies (3.5 and 6.5 MeV) and different fluences, ranging from 1.8·1016 to... 相似文献
42.
43.
Summary We prove a ?virtual connectedness? theorem for plane curves with nodes, cusps and ordinary triple points. Irreducible curves
are so obtained from virtually connected arrangements of lines.
Riassunto Viene dimostrato un teorema di ?virtuale connessione? per curve piane con nodi, cuspidi e punti tripli ordinari. Tale teorema viene poi applicato alla costruzione di curve irriducibili a partire da configurazioni di rette virtualmente connesse.相似文献
44.
We consider smooth non-degenerate surfaces in ℙ4, and prove that there is a finite number of such surfaces which are:
A complete list is given in both cases. 相似文献
(a) | sectionally non-special, i.e.h1(O C(1))=0, where C is a general hyperplane section of S; or |
(b) | not of general type and non-special (i.e. h1(O C(1))=0. |
45.
Simona Cirrincione Anna Luganini Cristina Lamberti Marcello Manfredi Laura Cavallarin Maria Gabriella Giuffrida Enrica Pessione 《Molecules (Basel, Switzerland)》2021,26(16)
Background: Milk is considered an important source of bioactive peptides, which can be produced by endogenous or starter bacteria, such as lactic acid bacteria, that are considered effective and safe producers of food-grade bioactive peptides. Among the various types of milk, donkey milk has been gaining more and more attention for its nutraceutical properties. Methods: Lactobacillus rhamnosus 17D10 and Lactococcus lactis subsp. cremoris 40FEL3 were selected for their ability to produce peptides from donkey milk. The endogenous peptides and those obtained after bacterial fermentation were assayed for their antioxidant, antibacterial, and antiviral activities. The peptide mixtures were characterized by means of LC-MS/MS and then analyzed in silico using the Milk Bioactive Peptide DataBase. Results: The peptides produced by the two selected bacteria enhanced the antioxidant activity and reduced E. coli growth. Only the peptides produced by L. rhamnosus 17D10 were able to reduce S. aureus growth. All the peptide mixtures were able to inhibit the replication of HSV-1 by more than 50%. Seventeen peptides were found to have 60% sequence similarity with already known bioactive peptides. Conclusions: A lactic acid bacterium fermentation process is able to enhance the value of donkey milk through bioactivities that are important for human health. 相似文献
46.
The cationic [RuCl(PNNP)]+ catalysts containing tetradentate ligands with a P2N2 donor set (PNNP) show strong electronic effects in the cyclopropanation of para‐substituted styrenes. The reactivity trend confirms that the carbene transfer to the olefin has electrophilic character. Linear free‐energy relationships are observed for the relative reactivity, the cis/trans selectivity, and for the enantioselectivity (of the cis‐cyclopropane). The linear correlation between log (kX/kH) and σ shows a large value of ρ (−2.4), which is indicative of significant charge buildup in the transition state of the carbene transfer to the olefin. All the relevant parameters (reactivity, diastereoselectivity, and enantioselectivity) increase with the increasing electron density at the C=C bond. To define the scope of the [RuCl(PNNP)]+ catalysts, 1‐ and 2‐substituted styrenes, and oct‐1‐ene were also investigated. 相似文献
47.
Filipponi E Cruciani G Tabarrini O Cecchetti V Fravolini A 《Journal of computer-aided molecular design》2001,15(3):203-217
Antiviral quinolones are promising compounds in the search for new therapeutically effective agents for the treatment of AIDS. To rationalize the SAR for this new interesting class of anti-HIV derivatives, we performed a 3D-QSAR study on a library of 101 6-fluoro and 6-desfluoroquinolones, taken either from the literature or synthesized by us. The chemometric procedure involved a fully semiempirical minimization of the molecular structures by the AMSOL program, which takes into account the solvatation effect, and their 3D characterization by the VolSurf/GRID program. The QSAR analysis, based on PCA and PLS methods, shows the key structural features responsible for the antiviral activity. 相似文献
48.
Janine Richter Saioa Elordui-Zapatarietxe Håkan Emteborg Ina Fettig Julie Cabillic Enrica Alasonati Fanny Gantois Claudia Swart Taner Gokcen Murat Tunc Burcu Binici Andres Rodriguez-Cea Tea Zuliani Adriana Gonzalez Gago Daniel Pröfrock Marjaana Nousiainen George Sawal Mirella Buzoianu Rosemarie Philipp 《Accreditation and quality assurance》2016,21(2):121-129
The European Water Framework Directive 2000/60/EC requires monitoring of organic priority pollutants in so-called whole water samples, i.e. in aqueous non-filtered samples that contain natural colloidal and suspended particulate matter. Colloids and suspended particles in the liquid phase constitute a challenge for sample homogeneity and stability. Within the joint research project ENV08 “Traceable measurements for monitoring critical pollutants under the European Water Framework Directive 2000/60/EC”, whole water test materials were developed by spiking defined amounts of aqueous slurries of ultra-finely milled contaminated soil or sediment and aqueous solutions of humic acid into a natural mineral water matrix. This paper presents the results of an European-wide interlaboratory comparison (ILC) using this type of test materials. Target analytes were tributyltin, polybrominated diphenyl ethers and polycyclic aromatic hydrocarbons in the ng/L concentration range. Results of the ILC indicate that the produced materials are sufficiently homogeneous and stable to serve as samples for, e.g. proficiency testing or method validation. To our knowledge, this is the first time that ready-to-use water materials with a defined amount of suspended particulate and colloidal matter have been applied as test samples in an interlaboratory exercise. These samples meet the requirements of the European Water Framework Directive. Previous proficiency testing schemes mainly employed filtered water samples fortified with a spike of the target analyte in a water-miscible organic solvent. 相似文献
49.
In the present study, penicillin G acylase (PGA), an enzyme belonging to the family of hydrolases, has been investigated as chiral selector in CE using the partial filling technique. Owing to the strong disposition of PGA to be adsorbed by the inner capillary wall, permanently coated capillaries were used to diminish both the protein-wall interactions and the EOF. In particular, the silica surface of the capillary was chemically coated by an antiadhesive and an hydrophilic layer of pullulan, a high-molecular-mass homopolysaccharide. The coating procedure consisted in the silanization with glycidoxypropyltrimethoxysilane and the subsequent coupling of the hydroxyl groups of pullulan onto the silanized capillary. Using this approach, a significant EOF suppression was obtained within a wide pH range (pH 3.0-9.0); this result was very important in order to find the suitable conditions for the application of partial filling technique. The optimization of partial filling was carried out by considering the effects of different experimental conditions (buffer pH, PGA concentration, and loading duration), on the migration time and enantioresolution of rac-ketoprofen. Under the selected conditions as: 100 mM sodium phosphate buffer (pH 5.5) containing 240 microM of PGA (partial filling of 120 s at a pressure of 50 mbar), a series of acidic compounds resulted to be enantioresolved in about 10 min. The long-term stability of the proposed coating was evaluated; more than 100 injections were performed without significant loss of reproducibility. 相似文献
50.
Thomas Scattolin Enrica Bortolamiol Flavio Rizzolio Nicola Demitri Fabiano Visentin 《应用有机金属化学》2020,34(10):e5876
Novel allyl palladium compounds stabilized by carbohydrate-based N-heterocyclic carbenes (NHCs) were prepared and characterized by nuclear magnetic resonance, high-resolution mass spectrometry and elemental analysis. The antiproliferative activity of the compounds was tested on a panel of different tumor lines, especially ovarian cancer and MRC-5 human lung fibroblasts (nontumor cells). These experiments showed that both mixed NHC/PPh3 and NHC/PTA (PTA = 1,3,5-triaza-7-phosphaadamantane) allyl complexes have IC50 (half maximal inhibitory concentration) values comparable and sometimes even significantly lower than cisplatin. Moreover, the mixed NHC/PTA allyl complexes exhibit good activity toward the seven tumor lines tested with a substantial inactivity against normal cells, a necessary condition to avoid the general cytotoxicity of a metallo-drug. Furthermore, this subclass of compounds proved particularly active on the A549 lung cancer tumor line (up to 100-fold more cytotoxic than cisplatin) and exhibited satisfactory cytotoxicity against KURAMOCHI and OVCAR3 cell lines, which are currently considered the best in vitro models for serous ovarian cancer, the most lethal tumor for women worldwide. 相似文献