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Journal of Pharmaceutical Analysis 2019年第5期9卷 324-331页

作者： Cristina Panella Rosella Ferretti Adriano Casulli roberto Cirilli Centro Nazionale peril Controllo e la Valutazione dei Farmaci Istituto Superiore di Sanita Viale Regina Elena 299 00161 Rome Italy European Union Reference Laboratory for the Parasites Istituto Superiore di Sanita Viale Regina Elena 299 00161 Rome Italy World Health Organization Collaborating Centre for the Epidemiology Detection and Control of Cystic and Alveolar Echinococcosis (in Animals and Humans) Istituto Superiore di Sanita Viale Regina Elena 299 00161 Rome Italy

Carvedilol is a chiral drug with potent antihypertensive and antianginal activities. Although it is clinically used as a racemic mixture, its enantiomers show different pharmacokinetic and pharmacodynamic profiles. Here, the direct chiral separation of racemic drug by high performance liquid chromatography using two immobilized-type amylose-based chiral stationary phases is presented. Some chromatographic parameters, such as retention and selectivity, were determined under multimodal eluent conditions and different temperatures. A temperature-dependent inversion of the elution order of enantiomers was observed in the operative temperature range of chiral chromatographic support. Finally, an effective direct enantioselective method was successfully applied to the separation of the enantiomers of carvedilol on a semipreparative scale.

关键词： Chiralpak^(■) IG-3 Enantioselective HPLC Carvedilol Column temperature Isoenantioselective temperature Semipreparative enantioseparation

A high aspect ratio surface micromachined accelerometer based on a SiC-CNT composite material

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Microsystems & Nanoengineering 2024年第2期10卷 219-230页

作者： Jiarui Mo Shreyas Shankar roberto Pezone Guoqi Zhang Sten Vollebregt Laboratory of Electronic Components Technology and Materials(ECTM)Department of MicroelectronicsDelft University of TechnologyDelftThe Netherlands

Silicon carbide(SiC)is recognized as an excellent material for microelectromechanical systems(MEMS),especially those operating in challenging environments,such as high temperature,high radiation,and corrosive ***,SiC bulk micromachining is still a challenge,which hinders the development of complex SiC *** address this problem,we present the use of a carbon nanotube(CNT)array coated with amorphous SiC(a-SiC)as an alternative composite material to enable high aspect ratio(HAR)surface *** using a prepatterned catalyst layer,a HAR CNT array can be grown as a structural template and then densified by uniformly filling the CNT bundle with LPCVD *** electrical properties of the resulting SiC-CNT composite were characterized,and the results indicated that the electrical resistivity was dominated by the *** demonstrate the use of this composite in MEMS applications,a capacitive accelerometer was designed,fabricated,and *** fabrication results showed that the composite is fully compatible with the manufacturing of surface micromachining *** Young’s modulus of the composite was extracted from the measured spring constant,and the results show a great improvement in the mechanical properties of the CNTs after coating with *** accelerometer was electrically characterized,and its functionality was confirmed using a mechanical shaker.

关键词： composite surface electrical

A review of the roles of forest canopy gaps

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Journal of Forestry Research 2014年第4期25卷 725-736页

作者： Adele Muscolo Silvio Bagnato Maria Sidari roberto Mercurio Department of Agraria "Mediterranea" University of Reggio Calabria Feo di Vito 89122 Reggio Calabria (Italy)

Treefall gap, canopy opening caused by the death of one or more trees, is the dominant form of disturbance in many forest systems worldwide. Gaps play an important role in forest ecology helping to pre- serve bio- and pedo-diversity, influencing nutrient cycles, and maintain- ing the complex structure of the late-successional forests. Over the last 30 years, numerous reviews have been written describing gap dynamics. Here we synthesize current understanding on gap dynamics relating to tree regeneration with particular emphasis on gap characteristics consid- ered critical to develop ecologically sustainable forest management sys- tems and to conserve native biodiversity. Specifically, we addressed the question： how do gaps influence forest structure？ From the literature re- viewed, the size of gaps induces important changes in factors such as light intensity, soil humidity and soil biological properties that influence tree species regeneration and differ in gaps of different sizes. Shade- tolerant species can colonize small gaps; shade-intolerant species need large gaps for successful regeneration. Additionally, gap dynamics differ between temperate, boreal, and tropical forests, showing the importance of climate differences in driving forest regeneration. This review summa- rizes information of use to forest managers who design cutting regimes that mimic natural disturbances and who must consider forest structure, forest climate, and the role of natural disturbance in their designs.

关键词： biodiversity gap cutting gap dynamic forest management forest restoration

Yield stress measurements and microstructure of colloidal kaolin powders clusterized and dispersed in different liquids

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Particuology 2009年第6期7卷 438-444页

作者： Dario T.Beruto Alberto Lagazzo Rodolfo Botter roberto Grillo Department of Civil Environmental and Architectural Engineering (DICAT)University of GenoaP.le Kennedy (Fiera del Mare)Pad. D16129-GenoaItaly Artigo S.p.A. loc.Carpeneto17014-Cairo Montenotte (SV)Italy

Rheologicat measurements of four colloidal kaolin powders dispersed in water, paraffinic oil and liquid rubber have been done at solid concentration （9 （VS/VL） in the range 8-33%. In quasi-static conditions the yield stress τ° values were derived. An S-shaped relationship between τ° and （9 exists, that allows to evaluate the percolation threshold θc values. In water θc ranges between 29% and 33%, while it is between 17% and 21% in oil and in liquid rubber. In water the microstructure units, i.e. the primary clusters among kaolin crystallites, are denser and bigger than the ones in the two other liquids. Furthermore, in quasistatic condition, the aqueous microstructure units have less tendency to cling together to form a network that can span all over the liquid phase. The different kaolin dispersions at θ equal to 22% are characterized by yield stress ranging between 7.S Pa and 59 Pa in water, 66-250 Pa in oil and 230-770 Pa in liquid rubber. It has been found that for any kaolin types the log τ°/ θ evaluated near to the percolation threshold is a conservative parameter of the three different liquids. These results are useful to design colloidal dispersions with selected microstructure.

关键词： Yield stress Colloid Dispersions Microstructure units Cluster Kaolin Rheology

Wavelet-based deconvolution of ultrasonic signals in nondestructive evaluation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第10期7卷 1748-1756页

作者： HERRERA roberto Henry OROZCO Rubén RODRIGUEZ Manuel Department of Informatics University of Cienfuegos Cienfuegos 59430 Cuba CEETI Central University of Las Villas Santa Clara 54830 Cuba Department of Physics Central University of Las Villas Santa Clara 54830 Cuba

In this paper, the inverse problem of reconstructing reflectivity function of a medium is examined within a blind deconvolution framework. The ultrasound pulse is estimated using higher-order statistics, and Wiener filter is used to obtain the ultrasonic reflectivity function through wavelet-based models. A new approach to the parameter estimation of the inverse filtering step is proposed in the nondestructive evaluation field, which is based on the theory of Fourier-Wavelet regularized deconvolution (ForWaRD). This new approach can be viewed as a solution to the open problem of adaptation of the ForWaRD framework to perform the convolution kernel estimation and deconvolution interdependently. The results indicate stable solutions of the esti- mated pulse and an improvement in the radio-frequency (RF) signal taking into account its signal-to-noise ratio (SNR) and axial resolution. Simulations and experiments showed that the proposed approach can provide robust and optimal estimates of the reflectivity function.

关键词： Blind deconvolution Ultrasonic signals processing Wavelet regularization

Autism genetics: Methodological issues and experimental design

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Science China(Life Sciences) 2015年第10期58卷 946-957页

作者： roberto SACCO Carla LINTAS Antonio M.PERSICO Department of Child Neuropsychiatry and Laboratory of Molecular Psychiatry and Neurogenetics University "Campus Bio-Medico" Department of Experimental Neurosciences I.R.C.C.S."Fondazione Santa Lucia"

Autism is a complex neuropsychiatric disorder of developmental origin, where multiple genetic and environmental factors likely interact resulting in a clinical continuum between "affected" and "unaffected" individuals in the general population. During the last two decades, relevant progress has been made in identifying chromosomal regions and genes in linkage or association with autism, but no single gene has emerged as a major cause of disease in a large number of patients. The purpose of this paper is to discuss specific methodological issues and experimental strategies in autism genetic research, based on fourteen years of experience in patient recruitment and association studies of autism spectrum disorder in Italy.

关键词： autistic disorder endophenotype genetic association genetics pervasive developmental disorders

Trans-sacral screw fixation in the treatment of high dyplastic developmental spondylolisthesis

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World Journal of Clinical Cases 2013年第3期1卷 116-120页

作者： Alessandro Landi Nicola Marotta Cristina Mancarella roberto Tarantino roberto Delfini Department of Neurology and Psychiatry Division of NeurosurgeryUniversity of Rome"Sapienza"00165 RomeItaly

We describe the case of a 67-year-old woman with L5-S1 ontogenetic spondylolisthesis treated with pedicle fixation associated with interbody arthrodesis performed with S1-L5 trans-sacral screwing according to the technique of Bartolozzi. The procedure was followed by a wide decompressive laminectomy. The patient had a progressive improvement of the symptoms which gradually disappeared in 12 mo. The radiograph at 6 and 12 mo showed complete fusion system. The choice of treatment in L5-S1 ontogenetic spondylolithesis is related to a correct clinical and diagnostic planning(X-ray, computer tomography magnetic resonance imaging, Measurement). In particular, the severity index and the square of unstable zone, and the standard measurements already described in the literature, are important to understand and to plane the correct surgical strategy, that require, in most of the times, fusion and interbody artrodesis.

关键词： High-dysplastic developmental spondylolisthesis Spondylolisthesis Trans-sacral screw Pelvic balance Spinopelvic imbalance

Viscosity in water from first-principles and deep-neural-network simulations

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npj Computational Materials 2022年第1期8卷 1318-1327页

作者： Cesare Malosso Linfeng Zhang roberto Car Stefano Baroni Davide Tisi SISSA—Scuola Internazionale Superiore di Studi Avanzati 34136TriesteItaly Program in Applied and Computational Mathematics Princeton UniversityPrincetonNJ08544USA DP Technology Beijing100080PR China Department of Chemistry Department of Physicsand Princeton Institute for the Science and Technology of MaterialsPrinceton UniversityPrincetonNJUSA CNR Istituto Officina dei Materiali SISSA Unit34136TriesteItaly

We report on an extensive study of the viscosity of liquid water at near-ambient conditions,performed within the Green-Kubo theory of linear response and equilibrium ab initio molecular dynamics(AIMD),based on density-functional theory(DFT).In order to cope with the long simulation times necessary to achieve an acceptable statistical accuracy,our ab initio approach is enhanced with deep-neural-network potentials(NNP).This approach is first validated against AIMD results,obtained by using the Perdew–Burke–Ernzerhof(PBE)exchange-correlation functional and paying careful attention to crucial,yet often overlooked,aspects of the statistical data ***,we train a second NNP to a dataset generated from the Strongly Constrained and Appropriately Normed(SCAN)*** the error resulting from the imperfect prediction of the melting line is offset by referring the simulated temperature to the theoretical melting one,our SCAN predictions of the shear viscosity of water are in very good agreement with experiments.

关键词： viscosity Strongly ambient

New challenges of geriatric cardiology： from clinical to preclinical research

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Journal of Geriatric Cardiology 2017年第4期14卷 223-232页

作者： Marco Malavolta Daniele Caraceni Fabiola Olivieri roberto Antonicelli Advanced Technology Center for Aging Research Scientific Technological Area IRCCS-INRCA Ancona Italy Department of Clinical and Molecular Sciences DISCLIMO Universit~ Politecnica delle Marche Ancona Italy Center of Clinical Pathology and Innovative Therapy INRCA Ancona Italy Department of Cardiology INRCA-IRCCS National Institute Ancona Italy

The field of geriatric cardiology reflects the evolving medical approaches tailored to address the needs of the growing population of oldest old with cardiovascular diseases （CVD）. The burden of CVD is expected to increase particularly for the most common types of chronic heart disease of the elderly including coronary artery disease, heart failure and atrial fibrillation. In this context of dramatic demographic changes, geriatric cardiologists are facing important challenges. In this review, we outline the basic concepts of geriatric cardiology and describe these challenges as well as the unmet needs around this discipline with also a focus on the translation from basic research.

关键词： Aging Cardiovascular Diseases Geriatric Cardiology Senescence

Multilevel oblique corpectomies as an effective surgical option to treat cervical chordoma in a young girl

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World Journal of Clinical Cases 2014年第3期2卷 57-61页

作者： roberto Delfini Daniele Marruzzo roberto Tarantino Nicola Marotta Alessandro Landi Department of Neurology and Psychiatry Division of Neurosurgery University of Rome "Sapienza"

Chordomas are malignant tumors arising from notochordal remnants. They are the most frequent tumors of the spine after plasmacytomas. Only 6% of chordomas are localized to the cervical level. In young patients, chordomas are rare and unpredictable. Despite this, the treatment of choice remains the total resection, as much as possible, followed by proton beam radiation. This case was managed using a precarotid and retrocarotid approach at the same time. The tumor was completely resected with the edges free from disease. The cervical spine was stabilized with an anterior plating C2-C4. Eighteen months after surgery the patient is still free from illness. Multilevel oblique corpectomies are an available and safe option for the treatment of upper cervical chordomas.

关键词： Cervical chordoma Multilevel oblique corpectomy Surgery RXT Retrocarotid approach