83 research outputs found

    β-nitro-5,10,15-tritolylcorroles

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    Functionalization of the β-pyrrolic positions of the corrole macrocycle with -NO 2 groups is limited at present to metallocorrolates due to the instability exhibited by corrole free bases under oxidizing conditions. A careful choice of the oxidant can limit the transformation of corroles into decomposition products or isocorrole species, preserving the corrole aromaticity, and thus allowing the insertion of nitro groups onto the corrole framework. Here we report results obtained by reacting 5,10,15-tritolylcorrole (TTCorrH 3) with the AgNO 2/ NaNO 2 system, to give mono- and dinitrocorrole derivatives when stoichiometry is carefully controlled. Reactions were found to be regioselective, affording the 3-NO 2TTCorrH 3 and 3,17-(NO 2) 2TTCorrH 3 isomers as the main products in the case of mono- and disubstitution, in 53 and 20% yields, respectively. In both cases, traces of other mono- and disubstituted isomers were detected, which were structurally characterized by X-ray crystallography. The influence of the β-nitro substituents on the corrole properties is studied in detail by UV-visible, electrochemical, and spectroelectrochemical characterization of these functionalized corroles. Density functional theory (DFT) and time-dependent DFT (TDDFT) calculations of the ground and excited state properties of these β-nitrocorrole derivatives also afforded significant information, closely matching the experimental observations. It is found that the β-NO 2 substituents conjugate with the π-aromatic system of the macrocycle, which initiates significant changes in both the spectroscopic and redox properties of the so functionalized corroles. This effect is more pronounced when the nitro group is introduced at the 2-position, because in this case the conjugation is, for steric reasons, more efficient than in the 3-nitro isomer. © 2012 American Chemical Society

    Fecal microbiota transplantation to improve efficacy of immune checkpoint inhibitors in renal cell carcinoma (TACITO trial)

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    Background: Renal cell carcinoma (RCC) is the 6° most common cancer in men and the 8° in women in the USA. In Italy RCC incidence was 11,500 new cases in 2017, while mortality was 3,371 cases in 2015. Increasing evidence suggests that response to immune checkpoint inhibitors (ICIs), a novel treatment for advanced RCC (aRCC) and other epithelial tumors, can be influenced by the patient gut microbiota. Fecal microbiota transplantation (FMT) is a novel treatment option aimed to restore healthy gut microbiota, and is the most effective therapy for recurrent C. difficile infection. Preliminary nonrandomized findings show that FMT is able to improve efficacy of ICIs in patients with advanced melanoma. The aim of this study is to evaluate, through a double-blinded placebo-controlled randomized clinical trial, the efficacy of targeted FMT (from donors who are responding to ICIs) in improving response rates to ICIs in subjects with aRCC. Methods: 50 patients who are about to receive, or have started by <8 weeks, pembrolizumab + axitinib as first-line therapy for aRCC will be enrolled. Exclusion criteria include major comorbidities, concomitant GI or autoimmune disorders, or HIV, HBV, HCV infection, continuative corticosteroid therapy, previous treatment with systemic immune-suppressants or immune-modulatory drugs, antibiotic therapy within 4 weeks prior to enrollment. Stool samples and clinical data will be collected at baseline. Then, patients will be randomized to donor FMT or placebo FMT. They will receive the first infusion by colonoscopy and then oral frozen fecal or placebo capsules (8 capsules t.i.d.) 90 and 180 days after the first FMT. Stool donors will be searched among long-term (>12 months) responders to ICIs, and will be selected by following protocols recommended by international guidelines. Patients in the FMT group will always receive feces from the same donor throughout the three fecal transplants. Frozen fecal batches and frozen fecal capsules will be manufactured according to international guidelines. Patients will be followed-up 7, 15, 30, 90, 180, 270, and 360 days after randomization for clinical evaluation and collection of stool samples. Patients will also undergo radiological assessment at 90, 180, 270 and 360 days after randomization. Microbiome analysis will be performed with shotgun metagenomics. The primary endpoint is the progression-free survival (PFS) at 12 months. Secondary endpoints are: objective response rate at 12 months; overall survival at 12 months; adverse events after FMT; microbiome changes after FMT. Sample size calculation was based on the hypothesis that FMT can improve the 1-year PFS rate from 60% (reported 1-year PFS for SOC) to 80% wen associated to SOC. Clinical trial information: NCT04758507

    Cabozantinib After a Previous Immune Checkpoint Inhibitor in Metastatic Renal Cell Carcinoma: A Retrospective Multi-Institutional Analysis

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    Background: Angiogenesis has been recognized as the most important factor for tumor invasion, proliferation, and progression in metastatic renal cell carcinoma (mRCC). However, few clinical data are available regarding the efficacy of cabozantinib following immunotherapy. Objective: To describe the outcome of cabozantinib in patients previously treated with immunotherapy. Patients and methods: Patients with mRCC who received cabozantinib immediately after nivolumab were included. The primary endpoint was to assess the outcome in terms of efficacy and activity. Results: Eighty-four mRCC patients met the criteria to be included in the final analysis. After a median follow-up of 9.4 months, median overall survival was 17.3 months. According to the IMDC criteria, the rates of patients alive at 12 months in the good, intermediate, and poor prognostic groups were 100%, 74%, and 33%, respectively (p < 0.001). The median progression-free survival (PFS) was 11.5 months (95% CI 8.3-14.7); no difference was found based on duration of previous first-line therapy or nivolumab PFS. The overall response rate was 52%, stable disease was found as the best response in 25.3% and progressive disease in 22.7% of patients. Among the 35 patients with progressive disease on nivolumab, 26 (74.3%) patients showed complete/partial response or stable disease with cabozantinib as best response after nivolumab. The major limitations of this study are the retrospective nature and the short follow-up. Conclusions: Cabozantinib was shown to be effective and active in patients previously receiving immune checkpoint inhibitors. Therefore, cabozantinib can be considered a valid therapeutic option for previously treated mRCC patients, irrespective of the type and duration of prior therapies

    The wide-field, multiplexed, spectroscopic facility WEAVE : survey design, overview, and simulated implementation

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    Funding for the WEAVE facility has been provided by UKRI STFC, the University of Oxford, NOVA, NWO, Instituto de Astrofísica de Canarias (IAC), the Isaac Newton Group partners (STFC, NWO, and Spain, led by the IAC), INAF, CNRS-INSU, the Observatoire de Paris, Région Île-de-France, CONCYT through INAOE, Konkoly Observatory (CSFK), Max-Planck-Institut für Astronomie (MPIA Heidelberg), Lund University, the Leibniz Institute for Astrophysics Potsdam (AIP), the Swedish Research Council, the European Commission, and the University of Pennsylvania.WEAVE, the new wide-field, massively multiplexed spectroscopic survey facility for the William Herschel Telescope, will see first light in late 2022. WEAVE comprises a new 2-degree field-of-view prime-focus corrector system, a nearly 1000-multiplex fibre positioner, 20 individually deployable 'mini' integral field units (IFUs), and a single large IFU. These fibre systems feed a dual-beam spectrograph covering the wavelength range 366-959 nm at R ∼ 5000, or two shorter ranges at R ∼ 20,000. After summarising the design and implementation of WEAVE and its data systems, we present the organisation, science drivers and design of a five- to seven-year programme of eight individual surveys to: (i) study our Galaxy's origins by completing Gaia's phase-space information, providing metallicities to its limiting magnitude for ∼ 3 million stars and detailed abundances for ∼ 1.5 million brighter field and open-cluster stars; (ii) survey ∼ 0.4 million Galactic-plane OBA stars, young stellar objects and nearby gas to understand the evolution of young stars and their environments; (iii) perform an extensive spectral survey of white dwarfs; (iv) survey  ∼ 400 neutral-hydrogen-selected galaxies with the IFUs; (v) study properties and kinematics of stellar populations and ionised gas in z 1 million spectra of LOFAR-selected radio sources; (viii) trace structures using intergalactic/circumgalactic gas at z > 2. Finally, we describe the WEAVE Operational Rehearsals using the WEAVE Simulator.PostprintPeer reviewe

    The wide-field, multiplexed, spectroscopic facility WEAVE: Survey design, overview, and simulated implementation

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    WEAVE, the new wide-field, massively multiplexed spectroscopic survey facility for the William Herschel Telescope, will see first light in late 2022. WEAVE comprises a new 2-degree field-of-view prime-focus corrector system, a nearly 1000-multiplex fibre positioner, 20 individually deployable 'mini' integral field units (IFUs), and a single large IFU. These fibre systems feed a dual-beam spectrograph covering the wavelength range 366-959\,nm at R5000R\sim5000, or two shorter ranges at R20000R\sim20\,000. After summarising the design and implementation of WEAVE and its data systems, we present the organisation, science drivers and design of a five- to seven-year programme of eight individual surveys to: (i) study our Galaxy's origins by completing Gaia's phase-space information, providing metallicities to its limiting magnitude for \sim3 million stars and detailed abundances for 1.5\sim1.5 million brighter field and open-cluster stars; (ii) survey 0.4\sim0.4 million Galactic-plane OBA stars, young stellar objects and nearby gas to understand the evolution of young stars and their environments; (iii) perform an extensive spectral survey of white dwarfs; (iv) survey 400\sim400 neutral-hydrogen-selected galaxies with the IFUs; (v) study properties and kinematics of stellar populations and ionised gas in z<0.5z<0.5 cluster galaxies; (vi) survey stellar populations and kinematics in 25000\sim25\,000 field galaxies at 0.3z0.70.3\lesssim z \lesssim 0.7; (vii) study the cosmic evolution of accretion and star formation using >1>1 million spectra of LOFAR-selected radio sources; (viii) trace structures using intergalactic/circumgalactic gas at z>2z>2. Finally, we describe the WEAVE Operational Rehearsals using the WEAVE Simulator.Comment: 41 pages, 27 figures, accepted for publication by MNRA

    The wide-field, multiplexed, spectroscopic facility WEAVE: Survey design, overview, and simulated implementation

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    WEAVE, the new wide-field, massively multiplexed spectroscopic survey facility for the William Herschel Telescope, will see first light in late 2022. WEAVE comprises a new 2-degree field-of-view prime-focus corrector system, a nearly 1000-multiplex fibre positioner, 20 individually deployable 'mini' integral field units (IFUs), and a single large IFU. These fibre systems feed a dual-beam spectrograph covering the wavelength range 366−959\,nm at R∼5000, or two shorter ranges at R∼20000. After summarising the design and implementation of WEAVE and its data systems, we present the organisation, science drivers and design of a five- to seven-year programme of eight individual surveys to: (i) study our Galaxy's origins by completing Gaia's phase-space information, providing metallicities to its limiting magnitude for ∼3 million stars and detailed abundances for ∼1.5 million brighter field and open-cluster stars; (ii) survey ∼0.4 million Galactic-plane OBA stars, young stellar objects and nearby gas to understand the evolution of young stars and their environments; (iii) perform an extensive spectral survey of white dwarfs; (iv) survey ∼400 neutral-hydrogen-selected galaxies with the IFUs; (v) study properties and kinematics of stellar populations and ionised gas in z1 million spectra of LOFAR-selected radio sources; (viii) trace structures using intergalactic/circumgalactic gas at z>2. Finally, we describe the WEAVE Operational Rehearsals using the WEAVE Simulator

    Sviluppo di Attuatori Polimerici per la Modulazione di Forma di Superfici Flessibili

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    In questo lavoro si sfrutta il principio fisico che è alla base del funzionamento di attuatori polimerici ad elastomeri dielettrici per sviluppare un dispositivo per il controllo di forma di superfici flessibili specifiche per determinate applicazioni. La capacità di modulare le configurazioni di determinati oggetti, in vari ambiti, è essenziale per adattare un particolare dispositivo all’ambiente che lo circonda o alle prestazioni che si vogliono ottenere. Molte idee sono state proposte e sono presenti in letteratura per la realizzazione di dispositivi innovativi, ad esempio per missioni spaziali, i quali, proprio grazie a cambiamenti conformazionali, possono realizzare azioni essenziali di locomozione o di afferraggio di oggetti. E’ importante, inoltre, in alcuni ambienti, dotarsi di dispositivi in grado di controllare le orientazioni di fotocellule per l’acquisizione di energia solare. Il controllo di forma, o shape control, è generalmente ottenuto attraverso l’utilizzo di motori elettromagnetici o altri complessi sistemi elettromeccanici. Le problematiche relative a questo tipo di dispositivi sono rilevanti in alcune applicazioni in cui i problemi di peso, di consumi energetici, di costo hanno un ruolo fondamentale, ad esempio in ambito aerospaziale o dell’ingegneria dei veicoli ad alte prestazioni. Ciò che questo lavoro si propone di ottenere è un dispositivo per il controllo di forma che abbia prestazioni più vantaggiose dal punto di vista applicativo rispetto ai dispositivi di comune utilizzo e che possa essere utilizzato in ambienti che richiedono le particolari caratteristiche descritte per soddisfare esigenze fondamentali, in particolari applicazioni totalmente innovative ideate nei centri di ricerca dell’Esa (European Spacial Agency). I risultati ottenuti e la realizzazione di un prototipo per il controllo di forma sono pienamente descritti nel capitolo. Il dispositivo per lo shape control si basa essenzialmente sull’utilizzo di attuatori polimerici nella configurazione detta ad estroflessione, localizzati in modo opportuno affinché la forma della superficie flessibile sia pienamente modulabile per mezzo dell’attivazione singola o contemporanea di più attuatori. La prima parte del lavoro di sperimentazione è stata quella di mettere a punto un attuatore in grado di rispondere con grandi deformazioni agli stimoli applicati. Gli esperimenti, le modalità di applicazione, le performance ottenute in relazione ai parametri quali allungamento e pressione esercitata, e le soluzioni ai problemi che si sono di volta in volta presentati, sono evidenziati nel capitolo 4. Questo studio ha portato alla fabbricazione e alla semplice riproducibilità di singoli attuatori capaci di modulare superfici flessibili attraverso i metodi descritti in seguito (capitolo 5). L’utilizzo di questo tipo di attuatori conferisce al sistema alte prestazioni, in relazione alla capacità di modificazione delle singole aree interessate, grazie alle caratteristiche di grande allungamento, di grande forza di attuazione, di velocità ed efficienza dei singoli oggetti utilizzati. Tali caratteristiche, invarianti rispetto alla scala, sono peculiari degli attuatori ad elastomeri dielettrici e hanno perciò conferito a questi ultimi maggiori possibilità di applicazione in questo ambito rispetto, ad esempio, agli attuatori di tipo elettrostatico, elettromagnetico, piezoelettrico, che tuttavia possono essere vantaggiosamente utilizzati per altre applicazioni ma esclusivamente su scala ridotta

    Studio teorico e sperimentale di un sistema di propulsione ad eliche per una capsula endoscopica in ambiente liquido

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    Submersible capsule is an active and wireless capsule able to navigate inside the stomach filled of water. The capsule is composed of a functional envelope containing a control/telemetry module, a battery and four motors. Motors allow the rotation of propellers localized in the rear side, which determine the locomotion of the capsule in ever direction
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