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171.
Francesco Bruni Mauro Sassi Marcello Campione Umberto Giovanella Riccardo Ruffo Silvia Luzzati Francesco Meinardi Luca Beverina Sergio Brovelli 《Advanced functional materials》2014,24(47):7410-7419
Small conjugated molecules (SM) are gaining momentum as an alternative to semiconducting polymers for the production of solution‐processed bulk heterojunction (BHJ) solar cells. The major issue with SM‐BHJs is the low carrier mobility due to the scarce control on the phase‐segregation process and consequent lack of preferential percolative pathways for electrons and holes to the extraction electrodes. Here, a new paradigm for fine tuning the phase‐segregation in SM‐BHJs, based on the post‐deposition exploitation of latent hydrogen bonding in binary mixtures of PCBM with suitably functionalized electron donor molecules, is demonstrated. The strategy consist in the chemical protection of the H‐bond forming sites of the donor species with a thermo‐labile functionality whose controlled thermal cleavage leads to the formation of stable, crystalline, phase‐separated molecular aggregates. This approach allows the fine tuning of the nanoscale film connectivity and thereby to simultaneously optimize the generation of geminate carriers at the donor–acceptor interfaces and the extraction of free charges via ordered phase‐separated domains. As a result, the PV efficiency undergoes an over twenty‐fold increase with respect to control devices. This strategy, demonstrated here with mixtures of diketopyrrolopyrrole derivatives with PCBM can be extended to other molecular systems for achieving highly efficient SM‐BHJ solar cells. 相似文献
172.
Marcello Iriti Giulio Colnaghi Farid Chemat Jacqueline Smadja Franco Faoro Franco A. Visinoni 《Flavour and Fragrance Journal》2006,21(4):704-712
The conventional hydrodistillation method (HD) has been compared with three different variants of the microwave‐assisted hydrodistillation technique (MADH), on Lavandula angustifolia flowers, both in terms of oil yield and effects on the glandular trichome morpho‐structure. The amount and composition of essential oil extracted in 4 h by HD was similar to that obtained in only 20 min by MADH and even lower than that extracted with a steam variant (MASD) of MADH itself. Histo‐cytochemical investigations and scanning electron microscopy showed that glandular trichome, after 4 h of HD, appeared swollen, with a deeply wrinkled surface and empty of essential oil, however maintaining the integrity of their cuticle. Many oil droplets were stuck to the outside of the trichome cuticle, sometimes arranged in large aggregates. After 20 min of MADH or MASD, trichomes appeared empty as well, but also particularly disrupted, or at least with holes in their head cuticle. Oil droplets were present outside the glands and in the inter‐rib regions of the flower calyx, except in the case of MASD. After this extraction method, neither oil droplets nor other lipid staining were present in the samples, confirming the effectiveness of this particular MADH technique. These investigations suggest that the rapidity of MADH and MASD in extracting essential oil is mainly due to the collapse of trichome structure and the consequent direct release of its content, without which it has to slowly permeate through membranes and cuticle, as in the case of HD. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
173.
Marcello Iriti Mara Rossoni Franco Faoro 《Journal of the science of food and agriculture》2006,86(10):1432-1438
Melatonin (N‐acetyl‐5‐methoxytryptamine) was detected by a modified HPLC method and ELISA tests in extracts of eight different Vitis vinifera cultivars, namely Nebbiolo, Croatina, Sangiovese, Merlot, Marzemino, Cabernet Franc, Cabernet Sauvignon and Barbera. Its concentration varied greatly among the cultivars, being the highest in Nebbiolo (0.965 ng g?1) and Croatina (0. 870 ng g?1). Field treatments of grapevine with the plant defence activator benzothiadiazole, greatly improved the melatonin content in berry skin extracts, indicating a possible strategy to raise the content of this important pharmaconutrient in plants, while inducing resistance to pathogens. The finding of this compound in grape suggests that the well‐established pharmaconutritional properties of this fruit are due not only to the presence of polyphenolic nutraceuticals, such as resveratrol, anthocyanins and proanthocyanidins, but also to the powerful antioxidant activity of melatonin. Copyright © 2006 Society of Chemical Industry 相似文献
174.
Filippo Maggi Fabrizio Papa Claudia Giuliani Laura Maleci Bini Alessandro Venditti Armandodoriano Bianco Marcello Nicoletti Romilde Iannarelli Giovanni Caprioli Gianni Sagratini Manuela Cortese Massimo Ricciutelli Sauro Vittori 《Flavour and Fragrance Journal》2015,30(2):139-159
As part of our research on local plants, including neglected horticultural crops to be rediscovered as culinary vegetables, we focused on Smyrnium olusatrum, a biennal herb used in cuisine for many centuries by Romans that has now been replaced by celery. We investigated the essential oil compositions of different plant organs collected in 18 populations of central Italy (Marche, Umbria, Abruzzo, Tuscany and Latium) by gas chromatography (GC) with a flame ionization detector and GC with mass spectrometry (MS) to identify the main chemotypes that occur. Owing to the presence of thermosensitive molecules such as isofuranodiene, curzerene and germacrone undergoing Cope‐rearrangement during the GC run, a truthful quantitative determination of these constituents was accomplished by high‐performance liquid chromatography with a diode‐array detector (HPLC‐DAD). Chemical data were supported by a chemometric technique in the form of principal component analysis, which allowed identification of chemical differences among organs. Furanosesquiterpenoids were the main fraction of the oils, with isofuranodiene as the most abundant in flowers and roots, furanoeremophil‐1‐one in leaves and roots and 1‐β‐acetoxyfuranoeudesm‐4(15)‐ene in fruits. To complete the phytochemical analysis, polar compounds such as chlorogenic acid, isoquercitin, 3‐indoleacetic acid and saccharose were isolated from the ethanolic extracts of the plant by column chromatography and structurally elucidated by nuclear magnetic resonance. Moreover, a morphological and histochemical survey on the secretory structures was performed, with the special aim to localize the sites of terpenes biosynthesis in both above‐ and belowground organs. Overall, the results can be considered important in the light of the recent interest in neglected edible plants for botanical food supplements and functional foods market. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
175.
Rosamaria Lappano Camillo Rosano Antonio Madeo Lidia Albanito Pierluigi Plastina Bartolo Gabriele Luca Forti Lucia Anna Stivala Domenico Iacopetta Vincenza Dolce Sebastiano Andò Vincenzo Pezzi Marcello Maggiolini 《Molecular nutrition & food research》2009,53(7):845-858
Resveratrol (RSV) is classified as a phytoestrogen due to its ability to interact with estrogen receptors (ERs). We assessed structure–activity relationships of RSV and the analogs 4,4′‐dihydroxystilbene (4,4′‐DHS), 3,5‐dihydroxystilbene (3,5‐DHS), 3,4′‐dihydroxystilbene (3,4′‐DHS), 4‐hydroxystilbene (4‐HS) using as model systems the ERα‐positive and negative MCF7 and SkBr3 breast cancer cells, respectively. In binding assays and transfection experiments RSV and the analogs showed the following order of agonism for ERα: 3,4′‐DHS > 4,4′‐DHS > 4‐HS > RSV, while 3,5‐DHS did not elicit any ligand properties. Computational docking analysis and real‐time PCR revealed for each analog a distinct ERα binding orientation and estrogen target gene expression profile. Interestingly, the aforementioned order of ligand activity was confirmed in proliferation assays which also showed the lack of growth stimulation by 3,5‐DHS. Our data suggest that subtle changes in the structure of the RSV derivatives examined may be responsible for the different ERα‐mediated biological responses observed in estrogen‐sensitive cancer cells. 相似文献
176.
Carlo Buoli Marcello Taverna Wanda Ternau Franco Todero 《Transactions on Emerging Telecommunications Technologies》1991,2(6):743-749
This work presents the theoretical calculation of the error probability as a function of the signal to noise ratio in presence of the oscillator phase noise in the 4 PSK and 16, 64, 256 and 1024 QAM systems. Experimental verifications confirm the computed values. On the basis of the procedure described herein, the design of two oscillators that operate in different modulation and capacity systems and with different values of the oscillation frequency is illustrated. 相似文献
177.
Marcello Murru Giovanni Giorgio Sara Montomoli Francois Ricard Frantisek Stepanek 《Chemical engineering science》2011,66(21):5045-5054
An integrated methodology for the scale-up of vacuum contact drying with intermittent agitation is described in this work. The methodology combines a mathematical model of vacuum contact drying, based on differential transient heat and energy balances, and a small-scale experimental apparatus for model validation and parameter estimation. The validated model was used for the estimation of drying times of six different pharmaceutical compounds at the pilot and manufacturing scale over a range of drying conditions – pressure 15–200 mbar, temperature 45–70 °C, solvents: acetone, water, methanol, n-propanol, and isopropyl acetate. The mean difference between predicted and actual drying times for the six compounds was less than 9%, which is considered a significant improvement over current semi-empirical approaches to vacuum contact drying scale-up. 相似文献
178.
179.
Tesfaye Yonatan Tariku Zemene Eyasu Prati Andrea Pelillo Marcello Shah Mubarak 《International Journal of Computer Vision》2019,127(9):1303-1320
International Journal of Computer Vision - In this paper, a unified three-layer hierarchical approach for solving tracking problem in a multiple non-overlapping cameras setting is proposed. Given a... 相似文献
180.
Mattia Emanuela Ligotti Anna Aiello Giulia Accardi Anna Calabr Marcello Ciaccio Claudia Colomba Danilo Di Bona Bruna Lo Sasso Fanny Pojero Antonino Tuttolomondo Calogero Caruso Giuseppina Candore Giovanni Duro 《International journal of molecular sciences》2022,23(24)
Natural killer (NK) cells play a role in defence against viral infections by killing infected cells or by producing cytokines and interacting with adaptive immune cells. Killer immunoglobulin-like receptors (KIRs) regulate the activation of NK cells through their interaction with human leucocyte antigens (HLA). Ninety-six Sicilian patients positive to Human Immunodeficiency Virus-1 (HIV) and ninety-two Sicilian patients positive to SARS-CoV-2 were genotyped for KIRs and their HLA ligands. We also included fifty-six Sicilian patients with chronic hepatitis B (CHB) already recruited in our previous study. The aim of this study was to compare the distribution of KIR–HLA genes/groups of these three different infected populations with healthy Sicilian donors from the literature. We showed that the inhibitory KIR3DL1 gene and the KIR3DL1/HLA-B Bw4 pairing were more prevalent in individual CHB. At the same time, the frequency of HLA-C2 was increased in CHB compared to other groups. In contrast, the HLA-C1 ligand seems to have no contribution to CHB progression whereas it was significantly higher in COVID-19 and HIV-positive than healthy controls. These results suggest that specific KIR–HLA combinations can predict the outcome/susceptibility of these viral infections and allows to plan successful customized therapeutic strategies. 相似文献