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991.
Barbara Roda Pierluigi Reschiglian Francesco Alviano Giacomo Lanzoni Gian Paolo Bagnara Francesca Ricci Marina Buzzi Pier Luigi Tazzari Pasqualepaolo Pagliaro Elisa Michelini Aldo Roda 《Journal of chromatography. A》2009,1216(52):9081-9087
New cell sorting methodologies, which are simple, fast, non-invasive, and able to isolate homogeneous cell populations, are needed for applications ranging from gene expression analysis to cell-based therapy. In particular, in the forefront of stem cell isolation, progenitor cells have to be separated under mild experimental conditions from complex heterogeneous mixtures prepared from human tissues. Most of the methodologies now employed make use of immunological markers. However, it is widely acknowledged that specific markers for pluripotent stem cells are not as yet available, and cell labelling may interfere with the differentiation process. This work presents for the first time gravitational field-flow fractionation (GrFFF), as a tool for tag-less, direct selection of human hematopoietic stem and progenitor cells from cell samples obtained by peripheral blood aphaeresis. These cells are responsible to repopulate the hemopoietic system and they are used in transplantation therapies. Blood aphaeresis sample were injected into a GrFFF system and collected fractions were characterized by flow cytometry for CD34 and CD45 expression, and then tested for viability and multi-differentiation potential. The developed GrFFF method allowed obtaining high enrichment levels of viable, multi-potent hematopoietic stem cells in specific fraction and it showed to fulfil major requirements of analytical performance, such as selectivity and reproducibility of the fractionation process and high sample recovery. 相似文献
992.
Alessandro Chiolerio Paola Martino Paolo Allia 《Journal of magnetism and magnetic materials》2009,321(19):3099-3103
Structure, morphology and magnetic properties of thermally evaporated Co/Cr multilayers and of the solid solution obtained by isothermal treatment of the layered samples have been studied to evaluate their potential application as high-coercivity materials for hard spin injectors in spintronic devices such as magnetic tunneling junctions. The thermal treatment was performed in a partial pressure of inert gas to allow interdiffusion of Cr and Co. Structure and composition of the materials, as well as the effects of the annealing treatment, have been investigated by field emission scanning electron microscopy and energy-dispersive X-ray analysis. The magnetic configuration of these films was investigated by magnetic force microscopy. Simultaneous measurements of two mutually perpendicular magnetisation components were performed by means of a vector vibrating sample magnetometer, and showed that the in-plane coercivity can be increased by proper thermal treatment from less than 10 Oe to about 240 Oe. However, annealing may result in a loss of compositional and morphologic homogeneity of the films. 相似文献
993.
Flavio Della Foglia Tonia Losco Paolo Piseri Paolo Milani Elena Selli 《Journal of nanoparticle research》2009,11(6):1339-1348
The photocatalytic activity of thin, nanostructured films of titanium dioxide, synthesized by supersonic cluster beam deposition
(SCBD) from the gas phase, has been investigated employing the photodegradation of salicylic acid as test reaction. Because
of the low deposition energy, the so-deposited highly porous TiO2 films are composed of nanoparticles maintaining their original properties in the film, which can be fully controlled by tuning
the deposition and post-deposition treatment conditions. A systematic investigation on the evolution of light absorption properties
and photoactivity of the films in relation to their morphology, determined by AFM analysis, and phase composition, determined
by Raman spectroscopy, has been performed. The absorption and photocatalytic activity of the nanostructured films in the visible
region could be enhanced either through post-deposition annealing treatment in ammonia containing atmosphere or employing
mild oxidation conditions, followed by annealing in N2 at 600 °C. 相似文献
994.
Thomas Chambrion Paolo Mason Mario Sigalotti Ugo Boscain 《Annales de l'Institut Henri Poincaré (C) Analyse Non Linéaire》2009
We prove approximate controllability of the bilinear Schrödinger equation in the case in which the uncontrolled Hamiltonian has discrete non-resonant spectrum. The results that are obtained apply both to bounded or unbounded domains and to the case in which the control potential is bounded or unbounded. The method relies on finite-dimensional techniques applied to the Galerkin approximations and permits, in addition, to get some controllability properties for the density matrix. Two examples are presented: the harmonic oscillator and the 3D well of potential, both controlled by suitable potentials. 相似文献
995.
Paolo Lo Meo 《Tetrahedron》2009,65(50):10413-39
Polarimetry was used in order to investigate the formation of supramolecular complexes between mono-6-amino-β-cyclodextrin and various p-nitroaniline derivatives at two different pH values. Comparison with the behaviour of native β-cyclodextrin gave us the opportunity to consider the effect exerted by the presence of charged groups, having different solvation requirements, on the binding equilibrium. Data offer some support to the hypothesis of ‘dynamic co-inclusion’ of solvent molecules within the host-guest complex. 相似文献
996.
We apply the method of Dalgarno and Lewis to scattering states and discuss the choice of the unperturbed model in order to have a convergent perturbation series for the phase shift. We show that a recently proposed approach is a particular case of the method of Dalgarno and Lewis. 相似文献
997.
Roberto E. Di Paolo Dr. João Seixas de Melo Prof. João Pina Hugh D. Burrows Prof. Jorge Morgado Prof. António L. Maçanita Prof. 《Chemphyschem》2007,8(18):2657-2664
Two p‐phenylenevinylene (PV) trimers, containing 3′‐methylbutyloxyl (in MBOPV3) and 2′‐ethylhexyloxyl (in EHOPV3) side chains, are used as model compounds of PV‐based conjugated polymers (PPV) with the purpose of clarifying the origin of fast (picosecond time) components observed in the fluorescence decays of poly[2‐methoxy‐5‐(2′‐ethylhexyloxy)‐p‐phenylenevinylene] (MEH‐PPV). The fluorescence decays of MBOPV3 and EHOPV3 reveal the presence of similar fast components, which are assigned to excited‐state conformational relaxation of the initial population of non‐planar trimer conformers to lower‐energy, more planar conformers. The rate constant of conformational relaxation kCR is dependent on solvent viscosity and temperature, according to the empirical relationship kCR=aηo?α?exp(?αEη/RT), where aηo?α is the frequency factor, ηo is the pre‐exponential coefficient of viscosity, Eη is the activation energy of viscous flow. The empirical parameter α, relating the solvent microscopic friction involved in the conformational change to the macroscopic solvent friction (α=1), depends on the side chain. The fast component in the fluorescence decays of MEH‐PPV polymers (PPVs), is assigned to resonance energy transfer from short to longer polymer segments. The present results call for revising this assignment/interpretation to account for the occurrence of conformational relaxation, concurrently with energy transfer, in PPVs. 相似文献
998.
Damiana Scuteri Laura Rombol Takafumi Hayashi Chizuko Watanabe Shinobu Sakurada Kengo Hamamura Tsukasa Sakurada Paolo Tonin Giacinto Bagetta Luigi A. Morrone Maria Tiziana Corasaniti 《Molecules (Basel, Switzerland)》2022,27(15)
Chronic pain is one of the most common causes of the need for clinical evaluation, acquiring more importance in the elderly with cognitive impairment. Reduced self-reporting capabilities cause unrelieved pain contributing to the development of agitation. Safe and effective pain treatment can afford the management of agitation without the serious increase in death risk associated with neuroleptics. To this aim, the essential oil of bergamot (BEO), proven by rigorous evidence to have strong preclinical anti-nociceptive and anti-allodynic properties, has been engineered (NanoBEO, patent EP 4003294) to allow randomized, double-blind, placebo-controlled trials (BRAINAID, ). The present study: (1) assesses the analgesic effects of a single therapeutic dose of NanoBEO, as supplied by an airless dispenser for clinical translation, in models of inflammatory, neuropathic, and sensitization types of pain relevant to clinic; (2) provides a dose–response analysis of the efficacy of NanoBEO on scratching behavior, a typical behavioral disturbance occurring in dementia. A single therapeutic dose of NanoBEO confirms efficacy following thirty minutes pre-treatment with capsaicin and on the central sensitization phase induced by formalin. Moreover, it has an ID50 of 0.6312 mg and it is efficacious on static and dynamic mechanical allodynia. Altogether, the gathered results strengthen the potential of NanoBEO for clinical management of pain and agitation. NCT04321889相似文献
999.