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81.
Brigida Silvestri Alessandro Pezzella Giuseppina Luciani Aniello Costantini Fabiana Tescione Francesco Branda 《Materials science & engineering. C, Materials for biological applications》2012,32(7):2037-2041
We report on a facile method towards a synthesis of novel hybrid heparin silica nanoparticles involving a modification of the Stober method. Tetrapropyl orthosilicate (TPOS) was used instead of the traditional TEOS or TMOS; by this way we could overcome the solubility problems of heparin in ethanol and exploit the good solubility of heparin in proper isopropanol–water mixtures. Aminopropyl triethoxysilane (APTS) was also used to have a good link of heparin to silica particles. SEM, DLS, FTIR and NMR proved that we did find conditions in which heparin conjugated silica particles were produced.Thermogravimetry allowed to evaluate the heparin/silica weight ratio to be 0.61. The efficiency of heparin binding to the particles was appreciated to be 35 wt.%. 相似文献
82.
83.
A. Galia G. Filardo S. Gambino R. Mascolino F. Rivetti G. Silvestri 《Electrochimica acta》1996,41(18):2893-2896
The preliminary results on the electrochemical activation of catalytic systems based on copper and cobalt complexes for the carbonylation of methanol to dimethylcarbonate at room temperature and atmospheric pressure are reported. Faradic yields up to 70%, with very high selectivity towards dimethylcarbonate, were observed with CuCl(2,2′-bipyridine). Positive results were also obtained, although with poorer catalytic activity, with other complexes such as CuCl(tetramethylethylenediamine), [Co(1,6-bis(2-oxyphenyl)-2, 5-diaza-1,5-hexadiene)]0.5 H2O and Co(2,4-pentanedionate)2. 相似文献
84.
GL Gigli A Scalise G Silvestri M Diomedi F Placidi MG Pomponi C Masala 《Canadian Metallurgical Quarterly》1996,87(3-4):181-189
We report the case of a mentally retarded 30 y.o. patient with partial trisomy of chromosome 9, affected by epilepsy. Following treatment with antiepileptic drugs (AEDs), the patient developed several rare complications: after beginning therapy with phenytoin, the patient developed pseudolymphoma; after monotherapy with carbamazepine (CBZ), the patient thereafter developed myoclonic jerks of upper and lower limbs upon awakening; after one year of treatment with valproate (VPA) the patient developed clinical and immuno-haematological signs of SLE. Gradual withdrawal of AED, obtained clinical remission. The possibility that the chromosomal abnormality of the patient was responsible for the three rare complications observed during AED therapy is considered. 相似文献
85.
Head trauma causes approximately 75,000 deaths each year in the United States. Both hypoxia and hypovolemia are individual predictors of poor outcome in the patient with severe head trauma. Management begins in the field and is focused on ensuring oxygenation and maintaining a blood pressure that supports cerebral perfusion. In the trauma center, intracranial pressure monitoring may be helpful in guiding the management of increased intracranial pressure. Mannitol, given in intermittent bolus infusions, is the therapy of choice for increased intracranial pressure. Hyperventilation has been shown to decrease cerebral perfusion and should be avoided; it is a temporizing procedure that is reserved for those cases that demonstrate signs of increased intracranial pressure pending initiation of other therapies. 相似文献
86.
The present paper deals with a novel hydrogen sulphide abatement process applying a combined chemical-biological process. The authors already dealt with this subject in the paper “Biotechnological H2S gas treatment with Thiobacillus ferrooxidans” [1], previously published in Chemical Engineering and Technology. This study, in particular, deals with over all process test runs in a laboratory scale plant with a single-stage immobilised biomass reactor. 相似文献
87.
Cybo-Ottone A. Nisoli M. Magni V. De Silvestri S. 《Quantum Electronics, IEEE Journal of》1992,28(8):1825-1829
Resonator misalignment sensitivity is shown to be a source of pulse fluctuations in femtosecond mode-locked dye lasers. A resonator configuration with low misalignment sensitivity, different from the usual nearly confocal one and better suited for active cavity length stabilization, is proposed, and its experimental testing is described 相似文献
88.
89.
Enrica Belluco Sergio Ferrari Sonia Silvestri Marco Marani 《Remote sensing of environment》2006,105(1):54-67
Tidal marshes are characterized by complex patterns both in their geomorphic and ecological features. Such patterns arise through the elaboration of a network structure driven by the tidal forcing and through the interaction between hydrodynamical, geophysical and ecological components (chiefly vegetation). Intertidal morphological and ecological structures possess characteristic extent (order of kilometers) and small-scale features (down to tens of centimeters) which are not simultaneously accessible through field observations, thus making remote sensing a necessary observation tool. This paper describes a set of remote sensing observations from several satellite and airborne platforms, the collection of concurrent ground reference data and the vegetation distributions that may be inferred from them, with specific application to the Lagoon of Venice (Italy). The data set comprises ROSIS, CASI, MIVIS, IKONOS and QuickBird acquisitions, which cover a wide range of spatial and spectral resolutions. We show that spatially-detailed and quantitatively reliable vegetation maps may be derived from remote sensing in tidal environments through unsupervised (K-means) and supervised algorithms (Maximum Likelihood and Spectral Angle Mapper). We find that, for the objective of intertidal vegetation classification, hyperspectral data contain largely redundant information. This in particular implies that a reduction of the spectral features is required for the application of the Maximum Likelihood classifier. A large number of experiments with different feature extraction/selection algorithms show that the use of four bands derived from Maximum Noise Fraction transforms and four RGBI broad bands obtained by spectral averaging yield very similar classification performances. The classifications from hyperspectral data are somewhat superior to those from multispectral data, but the close performance and the results of the features reduction experiments show that spatial resolution affects classification accuracy much more importantly than spectral resolution. Monitoring schemes of tidal environment vegetation may thus be based on high-resolution satellite acquisitions accompanied by systematic ancillary field observations at a relatively limited number of reference sites, with practical consequences of some relevance. 相似文献
90.
Abstract. Given a set S of radio stations located on a line and an integer h ≥ 1 , the MIN ASSIGNMENT problem consists in finding a range assignment of minimum power consumption provided that any pair of
stations can communicate in at most h hops. Previous positive results for this problem are only known when h=|S|-1 or in the uniform chain case (i.e., when the stations are equally spaced). As for the first case, Kirousis et al. [7] provided
a polynomial-time algorithm while, for the second case, they derive a polynomial-time approximation algorithm.
This paper presents the first polynomial-time, approximation algorithm for the MIN ASSIGNMENT problem. The algorithm guarantees
a 2-approximation ratio and runs in O(hn
3
) time. We also prove that, for fixed h and for ``well spaced' instances (a broad generalization of the uniform chain case), the problem admits a polynomial-time approximation scheme . This result significantly improves over the approximability result given by Kirousis {et al}.
Both our approximation results are obtained via new algorithms that exactly solve two natural variants of the MIN ASSIGNMENT
problem: the problem in which every station must reach a fixed one in at most h hops and the problem in which the goal is to select a subset of bases such that all the other stations must reach one base in at most h-1 hops.
Finally, we show that for h=2 the MIN ASSIGNMENT problem can be exactly solved in O(n
3
) time. 相似文献