1,694 research outputs found

    L'istruzione è sempre più rosa. La conferma delle migliori performances scolastiche delle ragazze: un'indagine in provincia di Pisa

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    Dalla fine del XIX secolo le ragazze italiane hanno progressivamente ridotto la distanza dai ragazzi per quanto riguarda l'istruzione. Attualmente terminano in tempo l'intero ciclo della scuola secondaria, senza interruzioni o ritardi, molto più frequentemente dei ragazzi. Attraverso l'applicazione di un modello logistico si sono studiate le performanes scolastiche della coorte di iscritti nel 2005 alle scuole secondarie di primo gradoo della provincia di Pisa, seguita fino alcompletamento dell'intero ciclo secondario nel 2013. Il risultato scolstico (successo, fallimento) è stato messo in funzione di una serie di predittori quali il sesso, la cittadinanza, il giudizio al termine della secondria di primo grado, tipo di scuola e titolo di studio dei genitori. I risultati mostrano chiaramente come le ragazze abbiano una propensione ad una carriera di successo sensibilmente maggiore (89% più alta di quella dei ragazzi

    Il quartiere stazione di Pisa fra trasformazione e conflitto

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    Abstract – The city of Pisa (Italy) has experienced in the last decade a high level of migration from countries of Northern and Central Africa, Eastern Europe and China. As often happens, the migrants of different ethnic groups are located in the neighborhood around the train station, both as regards the commercial activities and the housing. In addition, several areas of the district are used by migrants as a meeting place. From the point of view of the urban landscape, the district has experienced considerable demographic and visual transformations, which are an indication of conflict and the level of integration of migrants among themselves and with Italians residents. This article aims to show, in a diachronic perspective, the changes in the urban landscape occurred in the neighborhood and the elements of conflict that results, among other elements, from the analysis of the ordinances of the police recently posted in the district

    Assessment of three Resistance-Nodulation-Cell Division drug efflux transporters of Burkholderia cenocepacia in intrinsic antibiotic resistance

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    <p>Abstract</p> <p>Background</p> <p><it>Burkholderia cenocepacia </it>are opportunistic Gram-negative bacteria that can cause chronic pulmonary infections in patients with cystic fibrosis. These bacteria demonstrate a high-level of intrinsic antibiotic resistance to most clinically useful antibiotics complicating treatment. We previously identified 14 genes encoding putative Resistance-Nodulation-Cell Division (RND) efflux pumps in the genome of <it>B. cenocepacia </it>J2315, but the contribution of these pumps to the intrinsic drug resistance of this bacterium remains unclear.</p> <p>Results</p> <p>To investigate the contribution of efflux pumps to intrinsic drug resistance of <it>B. cenocepacia </it>J2315, we deleted 3 operons encoding the putative RND transporters RND-1, RND-3, and RND-4 containing the genes <it>BCAS0591</it>-<it>BCAS0593</it>, <it>BCAL1674</it>-<it>BCAL1676</it>, and <it>BCAL2822</it>-<it>BCAL2820</it>. Each deletion included the genes encoding the RND transporter itself and those encoding predicted periplasmic proteins and outer membrane pores. In addition, the deletion of <it>rnd-3 </it>also included <it>BCAL1672</it>, encoding a putative TetR regulator. The <it>B. cenocepacia rnd-3 </it>and <it>rnd-4 </it>mutants demonstrated increased sensitivity to inhibitory compounds, suggesting an involvement of these proteins in drug resistance. Moreover, the <it>rnd-3 </it>and <it>rnd-4 </it>mutants demonstrated reduced accumulation of N-acyl homoserine lactones in the growth medium. In contrast, deletion of the <it>rnd-1 </it>operon had no detectable phenotypes under the conditions assayed.</p> <p>Conclusion</p> <p>Two of the three inactivated RND efflux pumps in <it>B. cenocepacia </it>J2315 contribute to the high level of intrinsic resistance of this strain to some antibiotics and other inhibitory compounds. Furthermore, these efflux systems also mediate accumulation in the growth medium of quorum sensing molecules that have been shown to contribute to infection. A systematic study of RND efflux systems in <it>B. cenocepacia </it>is required to provide a full picture of intrinsic antibiotic resistance in this opportunistic bacterium.</p

    Abnormal Glucose Tolerance Is Associated with a Reduced Myocardial Metabolic Flexibility in Patients with Dilated Cardiomyopathy

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    Dilated cardiomyopathy (DCM) is characterized by a metabolic shift from fat to carbohydrates and failure to increase myocardial glucose uptake in response to workload increments. We verified whether this pattern is influenced by an abnormal glucose tolerance (AGT). In 10 patients with DCM, 5 with normal glucose tolerance (DCM-NGT) and 5 with AGT (DCM-AGT), and 5 non-DCM subjects with AGT (N-AGT), we measured coronary blood flow and arteriovenous differences of oxygen and metabolites during Rest, Pacing (at 130 b/min), and Recovery. Myocardial lactate exchange and oleate oxidation were also measured. At Rest, DCM patients showed a reduced nonesterified fatty acids (NEFA) myocardial uptake, while glucose utilization increased only in DCM-AGT. In response to Pacing, glucose uptake promptly rose in N-AGT (from 72 ± 21 to 234 ± 73 nmol/min/g, p<0.05), did not change in DCM-AGT, and slowly increased in DCM-NGT. DCM-AGT sustained the extra workload by increasing NEFA oxidation (from 1.3 ± 0.2 to 2.9 ± 0.1 mol/min/gO2 equivalents, p<0.05), while DCM-NGT showed a delayed increase in glucose uptake. Substrate oxidation rates paralleled the metabolites data. The presence of AGT in patients with DCM exacerbates both the shift from fat to carbohydrates in resting myocardial metabolism and the reduced myocardial metabolic flexibility in response to an increased workload. This trial is registered with ClinicalTrial.gov NCT02440217

    Rendimento a scuola: quanto penalizza essere stranieri? Un’indagine nella provincia di Pisa

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    I grandi flussi di immigrazione iniziati dopo gli anni ottanta stanno trasformando l’Italia in una società multietnica. Nell’attuale fase storica in cui, a causa della persistente crisi economica e dei conflitti internazionali, l’intolleranza e l’integralismo stanno aumentando è prioritario promuovere un’efficace interazione tra differenti culture, in un quadro di reciproco rispetto. In questa prospettiva, la scuola può giocare un ruolo fondamentale contrastando le discriminazioni contro i nati stranieri, attraverso il contenimento delle disuguaglianze nell’istruzione, come premessa per ridurre le frustrazioni e l’emarginazione ed alimentare un’armonia sociale e culturale

    FEED BUNK HEIGHT IMPACT ON DAIRY COW'S FRONT CLAWS. IMPACTO DA ALTURA DO COMEDOURO NAS PATAS DIANTEIRAS DE VACAS LEITEIRAS.

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    ABSTRACTClaw horn lesions are believed to develop from increased pedal bone mobility induced by changes in the corium tissue. During the planning of barns herd owners are faced with choices of materials and dimensions, as well as feed bunk heights. Among the causes that may lead to front claw injuries there is the height of the feed bunk, as the cow changes its postural behavior in order to reach the food. This research aimed to study the dairy cows' front claws force exerted during eating for determiningthe lesion risk factor of the feed bunk height. Eight dairy cows were placed in front of the feed bunk, their front claws stepped on the pressure assessment system, and the forces exerted on front claws due to the eating postural change were recorded. The mean pressure, the maximum pressure, the floor contact area, and the mean force per region were calculated. While the cow was eating, the highest mean pressure shifted slightly towards the sole. In the lateral claw the maximum pressurewas also shifted slightly towards the toe. No difference was found in the variables analyzed for both lateral and medial sides, as well for the force distribution in the left and right claws. Results of this experiment were not conclusive, not allowing explaining either laminitis or the corkscrew deformity as a result of the force exerted in the claws by means of height of the feed bunk being a risk factor.Keywords: lameness, animal welfare, feed bunk design

    Multienzymatic Stereoselective Reduction of Tetrasubstituted Cyclic Enones to Halohydrins with Three Contiguous Stereogenic Centers

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    The asymmetric hydrogenation of conjugated tetrasubstituted alkenes with transition-metal catalysts is a challenging reaction, especially for substrates bearing a halide substituent. We describe a two-step multienzymatic reduction of a series of α-halo β-alkyl tetrasubstituted cyclic enones, affording halohydrins with three contiguous stereogenic centers, in good yield and with a high stereoselectivity. The reduction is catalyzed by a stereospecific ene-reductase (OYE2-3 or NemA) and a highly enantioselective alcohol dehydrogenase (ADH). The use of two enantiodivergent ADHs allows the control of the diastereoselectivity. The absolute stereochemical configurations of the products have been determined from the analysis of single-crystal structures (Flack's parameter). The enantiomeric excess (ee) has been determined by derivatization of the products with (R) Mosher's acid. Lastly, we extended our methodology also to a nonhalogenated substrate: the α-methyl ketoisophorone was reduced by two distinct enantiodivergent ene-reductases (flavin mononucleotide- and F 420-dependent), affording each enantiomer of the saturated ketone with ee > 98%

    Curcumin-Based β-Diketo Ligands for Ga3+: Thermodynamic Investigation of Potential Metal-Based Drugs

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    Curcumin is known for its therapeutic properties; among these, antioxidant, anti-inflammatory and anti-cancer ones stand out. Besides, curcumin metal complexes have shown widespread application in medicine and can be exploited as lead structures for developing metal-based drugs. Unfortunately, curcumin is poorly bioavailable, mainly due to its instability in physiological conditions; this weakness is tightly connected to the presence of the β-diketo moiety undergoing tautomeric equilibrium. Stability and metal-chelating ability can be tuned by modulating the electronic effects and steric hindrance close to the β-diketo moiety; in addition, formation of a metal complex shifts the tautomeric equilibrium towards the β-keto–enol form and increases stability in biological media. Among the metals used in clinical therapy, gallium nitrate has shown to have significant antitumor activity against non-Hodgkin lymphoma and bladder cancer, thus indicating that gallium-based drugs have potential for further development as antineoplastic agents with improved therapeutic activity. Curcuminoids have demonstrated high affinity for gallium(III), allowing the formation of stable positively charged M:L 1:2 β-diketonate complexes that benefit from the therapeutic activity of both the metal and the ligand. Seven new curcumin derivatives were synthesized and completely characterized. The new derivatives retain the solvent-dependent keto–enol tautomerism, with the prevalence of the diketo form in aqueous solution. Enhanced stability in simulated physiological conditions was observed in comparison to the lead compound curcumin. The presence of Ga3+ anticipates the dissociation of the enolic proton, allowing chelate complex formation, and simultaneously it shifts the tautomeric equilibrium towards the keto–enol form. A complete 1H/13C NMR and UV–Vis study was performed to define the metal-to-ligand stoichiometry ratio and the overall stability constants. In addition, we demonstrated that some of the derivatives have increased antiproliferative activity on colon cancer cells compared to curcumin and antioxidant properties. On the whole, the synthesized curcumin-based molecules may act as new gallium(III) chelators with improved stability with respect to curcumin and could open interesting perspectives for the development of novel therapeutic agents for cancer
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