169,986 research outputs found
Telerilevamento iperspettrale da piattaforma aerea: individuazione di coperture in cemento-amianto di edifici urbani e rurali
No full text“La soddisfazione sessuale come dimensione positiva”, IX Congresso Nazionale della Società Italiana di Psicologia della Salute (SIPSA), Bergamo, 23-25 Settembre 2010.
No full textAspetti metodologici ed operativi nella caratterizzazione di coperture in cemento amianto: l’esempio del comune di Broni (PV)
No full textHyperspectral Remote Sensing in environmental monitoring: Detailed mapping of asbestos concrete sheeting and in illegal stocking area
No full textSEG/Calgary 2000, Society of Exploration Geophysicists International Exposition, Seventieth Annual Meeting
Calgary, U.S.A
Environmental applications of airborne hyperspectral remote sensing: asbestos concrete sheeting identification and mapping
No full textFourteenth International Conference and Workshops on Applied Geologic Remote Sensing, August, Las Vegas, Nevad
A formal total synthesis of eleutherobin through an unprecedented kinetically controlled ring-closing-metathesis reaction of a densely functionalized diene
No full textThe key step in a formal total synthesis of
eleutherobin was an unprecedented kinetically
controlled RCM reaction of a densely functionalized diene 1 bearing two
PMP-protected allylic alcohols in the presence
of a second-generation Grubbs catalyst. Subsequent isomerization of the E 10-membered enedione 2 to the more stable Z isomer and cleavage of the MOM
protecting group led to the known precursor 3. MOM=methoxymethyl; PMP=p-methoxyphenyl
A formal total synthesis of eleutherobin using the ring-closing metathesis (RCM) reaction of a densely functionalized diene as the key step: Investigation of the unusual kinetically controlled RCM stereochemistry
No full textAsymmetric oxyallylation reactions and ring-closing metathesis have been used to synthesize compound 3, a key advanced intermediate used in the total synthesis of eleutherobin reported by Danishefsky and coworkers. The aldebyde 6, which is readily prepared from commercially available R-(-)-carvone in six steps in 30% overall yield on multigram quantities, was converted into the diene 5 utilizing two stereoselective titanium-mediated Hafner-Duthaler oxyallylation reactions. The reactions gave the desired products (8 and 12) in high yields (73 and 83%, respectively) as single diastereoisomers, with the allylic alcohol already protected as the p-methoxyphenyl (PMP) ether, which previous work has demonstrated actually aids ring-closing metathesis compared to other protective groups and the corresponding free alcohol. Cyclization under forcing conditions, using Grubbs' second-generation catalyst 13, gave the ten-membered carbocycle (E)-14 in 64% yield. This result is in sharp contrast to similar, but less functionalized, dienes, which have all undergone cyclization to give the Z stereoisomers exclusively. A detailed investigation of this unusual cyclization stereochemistry by computational methods has shown that the E isomer of the ten-membered carbocycle is indeed less thermodynamically stable than the corresponding Z isomer. In fact, the selectivity is believed to be due to the dense functionality around the ruthenacyclobutane intermediate that favors the transruthenacycle, which ultimately leads to the less stable E isomer of the ten-membered carbocycle under kinetic control. During the final synthetic manipulations the double bond of enedione (E)-16 isomerized to the more thermodynamically stable enedione (Z)-4, giving access to the advanced key-intermediate 3, which was spectroscopically and analytically identical to the data reported by Danishefsky and co-workers, and thereby completing the formal synthesis of eleutherobin
Impatto della Diga delle Tre Gole nella Contea di Zhong Xiang: Analisi mediante telerilevamento e GIS
No full textrivista con referaggi
"Disagio, benessere psicologico e genitorialità nelle condizioni di fertilità e infertilità", IX Congresso Nazionale della Società Italiana di Psicologia della Salute. Bergamo, 23-25 Settembre 2010.
No full textEcotoxicological Characterization of Type C Killer Whales From Terra Nova Bay (Ross Sea, Antarctica): Molecular Biomarkers, Legacy, and Emerging Persistent Organic Contaminants
No full textAmong killer whale forms, type C is a fish-eating form and is the most common in the Ross Sea. In the austral summer 2015, a study was conducted to evaluate the toxicological hazard these marine mammals face in the Antarctic ecosystem. Seven biopsy samples were collected from adult individuals (five males and two females) in the surroundings of the Italian Research Station Mario Zucchelli, Terra Nova Bay, by remote dart sampling from the pack ice. The accumulation levels of persistent organic pollutants (POPs) such as legacy (DDTs, PCBs, and HCB) and emerging (PBDEs and DP) were measured. Moreover, the protein expression of cytochrome P450 (CYP1A1 and 2B) and the mRNA level variations of the peroxisome proliferator-activated receptors α and γ (PPARα-γ) and the estrogen receptor α (ERα), aryl hydrocarbon receptor (AhR), and Cyp1a were evaluated. Twenty PCB congeners, six DDTs, HCB, three HCHs, and fourteen brominated BDEs and DP-syn and anti-isomers were analyzed on freeze-dried blubber biopsy samples by GC-MS. The protein expression was evaluated by Western Blot and the mRNA levels were quantified by quantitative real-time PCR. The average abundance pattern for the contaminants was DDTs > PCBs > HCB > HCHs ≈ PBDEs >> DP. Contaminant levels resulted to be lower when compared to the existing data from the Antarctic type C killer whales from the McMurdo Sound (Ross Sea) and those reported for fish-eating killer whales worldwide. The mRNA levels of the five target genes were successfully quantified, but no statistical correlation was found with POP levels, suggesting that either the low levels of quantified POPs in blubber may not significantly affect the biological responses investigated, or that other stressors could contribute to the alterations of the molecular biomarkers. Although the results showed a lower risk related to contamination compared to more impacted areas, this study provides baseline data for the conservation of this species in an area with high ecological value, recently declared as the largest Marine Protected Area in Antarctica, where pollutants should remain at minimum levels despite increasing multiple stresses existing in the region
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