169,747 research outputs found
Directed ortho-metalation–nucleophilic acyl substitution strategies in deep eutectic solvents: the organolithium base dictates the chemoselectivity
No full textDirected ortho metalation (DoM) or nucleophilic acyl substitution (SNAc) can be efficiently programmed on the same aromatic carboxylic acid amide, in a choline chloride-based eutectic mixture, by simply switching the nature of the organolithium reagent. Telescoped, one-pot ortho-lithiation/Suzuki-Miyaura cross-couplings have also been demonstrated for the first time in Deep Eutectic Solvents
Integrating administrative data-bases, passive surveillance and GIS.
No full textIntegration of data from different sources could provide an effective support in the epidemiological analysis of animal diseases, even in small-scale areas. Our need to integrate GIS (the Veterinary Service of the Province of Reggio Emilia has georeferred, among the ohers, all the bovine, swine, ovi-caprine and poultry farms) and the other administrative data-bases (the National Data Bank and our local data bank ) to gather, manipulate and analyze data from different sources found solution in the use of the ‘R’ software (www.r-project.org - 1). ‘R’ is a highly flexible, expandible and customizable statistical open-source software and an environment which provides all the necessary tools for data analysis and manipulation. R has also the capability of accessing data from a PostgreSQL server (where data are daily exported from the administrative data banks), via the ‘RODBC’ library, and provides tools for reading, writing and manipulating shapefiles (via the ‘maptools’ library) and advanced and modern instruments for the analysis of geographical data (i.e. the packages: ‘splancs’, ‘spdep’, ‘spatial’, ‘spatstat’, ‘Dcluster’). A real-life example of a successful application of this integrated approach is represented by the analysis of echinococcosis passive surveillance data. During the 5-year period 2001-2005, 229 cases of bovine echinococcosis (from 180 farms of the province of Reggio Emilia, Emilia-Romagna Region, Northern Italy), were found at slaughtering through meat inspection, and reported to the Veterinary Service of the Local Health Unit of Reggio Emilia. In order to estimate the prevalence of echinococcosis at the moment of slaughtering, all the data about cattle from the province slaughtered in the above-mentioned period (218,726 records from 2781 farms) were retrieved from the national data bank (the system which tracks all movements of the Italian bovine population). Since all the reports of the disease concerned cows over 2 years of age and became from only two big slaughterhouses in Lombardy region, the dataset and all the subsequent analyses were restricted only to the cows slaughtered in these two slaughterhouses (48,390 cows from 2003 farms), considering them as a random sample (about 46%) of all the cows over 2 years of age sent to the slaughterehouse from farms in the province.
Results and discussion. The prevalence of echinococcosis in cows at slaughtering was 4.7 (95% c.i.: 4.15-5.4) cases / 1000 animals. Both empirical Bayes estimates and kernel smoothing techniques were used to investigate the pattern of spatial distribution of the cases. The analysis revealed a heterogeneity in the prevalence estimates by municipality wich was not attributable to the effect of chance alone. In particular, a cluster of cases was identified in the north-western area of the province corresponding to 6 municipalities, where the highest prevalence reached 13.9 cases / 1000 cows. It is worth noting that, in the same area and in the same period, uncontrolled and illegal grazing of infected ovine flocks caused an outbreak of Brucella melitensis infection in cattle, sheep and goats. These findings could suggest that uncontrolled flock grazing could have represented a risk factor for echinococcosis in the cattle coming from the area considered, especially due to the possible presence of infected dogs or the abandoned carcasses and viscera of sheep (2).
The results presented here demonstrate how the goal of gathering and coherently assembling data from different sources (passive surveillance, geographical information system and administrative data-bases, such as the National Data Bank) can be succesfully achieved through (and from within) the open-source environment ‘R’, that provided not only the necessary statistical tools but also a common interface to GIS and databases
Effetti dei nematodi gastro-intestinali sulla crescita e sulla produzione di lana in pecore
No full textA Mild, Efficient and Sustainable Tetrahydropyranylation of Alcohols Promoted by Acidic Natural Deep Eutectic Solvents
No full textA straightforward protocol to promote the tetrahydropyranylation of alcohols, using for the first time bioinspired acidic natural deep eutectic solvents (NADESs) as non-innocent reaction media under mild reaction conditions, was reported. This approach enables the preparation of several tetrahydropyranyl (THP) ethers starting from primary, secondary and tertiary alcohols in short reaction times and with high levels of chemoselectivity, working under air and without the need of additional catalyst. The sustainability of the methodology was further highlighted by its scalability and the easy recyclability of the NADES, allowing multigram preparations of THP ethers without any loss of the catalytic activity of the reaction media up to ten recycling steps. Telescoped, one-pot tetrahydropyranylation/nucleophilic acyl substitution transformations using the same eutectic mixture were also demonstrated
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
A Fast and General Route to Ketones from Amides and Organolithium Compounds under Aerobic Conditions: Synthetic and Mechanistic Aspects
No full textWe report that the nucleophilic acyl substitution reaction of aliphatic and (hetero)aromatic amides by organolithium reagents proceeds quickly (20 s reaction time), efficiently, and chemoselectively with a broad substrate scope in the environmentally responsible cyclopentyl methyl ether, at ambient temperature and under air, to provide ketones in up to 93 % yield with an effective suppression of the notorious over-addition reaction. Detailed DFT calculations and NMR investigations support the experimental results. The described methodology was proven to be amenable to scale-up and recyclability protocols. Contrasting classical procedures carried out under inert atmospheres, this work lays the foundation for a profound paradigm shift of the reactivity of carboxylic acid amides with organolithiums, with ketones being straightforwardly obtained by simply combining the reagents under aerobic conditions and with no need of using previously modified or pre-activated amides, as recommended
Mitomycin C in highly myopic eyes - Author reply
No full textOphthalmology. 2005 Feb;112(2):208-18; discussion 219.
Mitomycin C modulation of corneal wound healing after photorefractive keratectomy in highly myopic eyes.
Gambato C, Ghirlando A, Moretto E, Busato F, Midena E.
SourceRefractive Surgery Service and Antimetabolite Therapy Research Unit, Department of Ophthalmology, University of Padova, Padova, Italy.
Abstract
PURPOSE: To evaluate the role of topical mitomycin C in corneal wound healing (CWH) after photorefractive keratectomy (PRK) in highly myopic eyes.
DESIGN: Prospective, double-masked, randomized clinical trial.
PARTICIPANTS: Seventy-two eyes of 36 patients affected by high (>7 diopters) myopia.
METHODS: In each patient, one eye was randomly assigned to PRK with intraoperative topical 0.02% mitomycin C application, and the fellow eye was treated with a placebo. Postoperatively, mitomycin C-treated eyes received artificial tears (3 times daily, tapered in 3 months), whereas the fellow eye was treated with fluorometholone sodium 2% and artificial tears (3 times daily, tapered in 3 months).
MAIN OUTCOME MEASURES: Uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA), contrast sensitivity, manifest refraction, and biomicroscopy. Contrast sensitivity was determined using the Pelli-Robson chart. Corneal confocal microscopy documented CWH.
RESULTS: Mean follow-up was 18 months (range, 12-36). No side effects or toxic effects were documented. At 12-month follow-up examination, UCVAs (logarithm of the minimum angle of resolution) were 0.4+/-0.48 and 0.5+/-0.53 (P = .03) in mitomycin C-treated eyes and corticosteroid-treated eyes, respectively. At 1 year, corneal haze developed in 20% of corticosteroid-treated eyes, versus 0% of mitomycin C-treated eyes. At 12, 24, and 36 months, corneal confocal microscopy showed activated keratocytes and extracellular matrix significantly more evident in untreated eyes (Ps = 0.004, 0.024, and 0.046, respectively).
CONCLUSION: Topical intraoperative application of 0.02% mitomycin C can reduce haze formation in highly myopic eyes undergoing PRK.
Comment in
Ophthalmology. 2006 Feb;113(2):357; author reply 357-8
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