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111.
Fabrizio De MattiaIlaria Bruni Andrea GalimbertiFrancesca Cattaneo Maurizio CasiraghiMassimo Labra 《Food research international (Ottawa, Ont.)》2011,44(3):693-702
The objective of the present work is to evaluate the efficacy of a DNA barcoding approach as a tool for the recognition of commercial kitchen spices belonging to the Lamiaceae family that are usually sold as enhancers of food flavor. A total of 64 spices samples, encompassing six different genera (i.e. Mentha, Ocimum, Origanum, Salvia, Thymus and Rosmarinus) were processed with a classical DNA barcoding approach by amplifying and sequencing four candidate barcode regions (rpoB, rbcL, matK and trnH-psbA) with universal primers. Results suggest that the non-coding trnH-psbA intergenic spacer is the most suitable marker for molecular spices identification followed by matK, with interspecific genetic distance values ranging between about 0% to 7% and 0% to 5%, respectively. Both markers were almost invariably able to distinguish spices species from closest taxa with the exclusion of samples belonging to the genus Oregano. Moreover, in a context of food traceability the two markers are useful to identify commercial processed spice species (sold as dried plant material). We also evaluated the potential benefits of a multilocus barcode approach over a single-marker and although the most suitable combination was the matK + trhH-psbA, the observed genetic distances values were very similar to the discriminatory performance of the trnH-psbA. Finally, this preliminary work provide clear evidences that the efficacy of a DNA barcoding approach to the recognition of commercial spices is biased by the occurrence of taxonomic criticisms as well as traces of hybridization events within the family Lamiaceae. For this reason, to better define a more practical and standardized DNA barcoding tool for spices traceability, the building of a dedicated aromatic plants database in which all species and cultivars are described (both morphologically and molecularly) is strongly required. 相似文献
112.
Fabrizio Bezzo Francesco Micheletti Riccardo Muradore Massimiliano Barolo 《Journal of Process Control》2005,15(8):1609-930
The use of model predictive control (MPC) in middle-vessel continuous distillation column (MVCC) is discussed. It is shown that using a 5 × 5 MPC implementation (where all levels are included in MPC as integral process variables) allows using a smaller middle-vessel, particularly when disturbances can be measured: a good performance is ensured without having the middle vessel drained or overfilled. Also, it is shown that MPC practically circumvents the issue of tuning the middle-vessel level controller. Furthermore, the MVCC design makes conventional decentralised control perform comparably to MPC. 相似文献
113.
Four experiments are reported that were aimed at elucidating some of the controversial issues concerning the preference for facelike patterns in newborns. The experiments were devised to contrast the original and the revised versions of the sensory hypothesis and the structural hypothesis as accounts of face preference in newborns. Experiments 1A and 1B supported the structural hypothesis by showing a visual preference for the stimulus for which components were located in the correct arrangement for a human face. Experiment 2 supported the sensory hypothesis by showing a visual preference for stimuli that were designed to have the optimal spatial frequency components for the newborn visual system. Experiment 3 showed that babies directed attention to a facelike pattern also when it was presented simultaneously with a nonfacelike stimulus with optimal spatial frequency for the newborn visual system. 相似文献
114.
115.
Yoshiyuki Abe Fabrizio Tappero Yuki Tanaka Yoshiki Takagi Giovanni Maizza 《Microgravity science and technology》2006,18(3-4):178-183
The effect of gravity on materials processing is rather complicated, and a large number of considerably unexpected results due to high gravity or sometimes centrifugation have been reported. The authors have been conducting high gravity diamond thin film growth by the DC-plasma CVD method up to 100 G. The effects of high gravity appeared in the nucleation site density, growth rate, grain size, uniformity, film coverage and morphology. With the increase in gravity, the nucleation site density, growth rate, grain size were all found to be increased, the uniformity and film coverage were improved, and {100} facet became dominant rather than {111} facet. To understand the deposition mechanism in these effects observed in high gravity, a diagnostic apparatus for spectroscopic study of the optical emission from the DC-plasma was developed, and the OES (optical emission spectroscopy) apparatus has been employed in high gravity CVD experiments. The influence of gravity on the most active species in the plasma, such as H, CH, C2 was discussed together with the results from the Raman spectroscopy and X-ray diffraction study. 相似文献
116.
EBMT by tree-phrasing 总被引:1,自引:1,他引:0
This article presents an attempt to build a repository storing associations between simple syntactic dependency treelets in
a source language and their corresponding phrases in a target language. We assess the usefulness of this resource in two different
settings. First, we show that it improves upon a standard subsentential translation memory. Second, we observe improvements
in translation quality when a standard statistical phrase-based translation engine is augmented with the ability to exploit
such a repository. 相似文献
117.
S Messinetti L Giacomelli A Manno R Finizio G Fabrizio AV Granai P Busicchio V Lauria 《Canadian Metallurgical Quarterly》1998,69(4):479-82; discussion 482-3
The authors, on the basis of 3 cases of complicated diverticular disease, discuss the indications to surgery, considering the advantages and disadvantages of the various surgical techniques and examining in particular the rules for a correct operation with resection and primary or secondary anastomosis. As they performed a rectosigmoidectomy with primary high colorectal anastomosis, they report the reasons why they adopted the preservation and peeling of the inferior mesenteric artery (IMA). 相似文献
118.
Fabrizio Frezza Alessandro Galli Paolo Lampariello 《Journal of Infrared, Millimeter and Terahertz Waves》1996,17(1):137-152
In this work, the quality factors and the coupling effects have been investigated for parallelepiped dielectric resonators in nonradiative dielectric (NRD) waveguide, in order to achieve fundamental information for the design of various types of advanced filters. The unloaded quality factor has been calculated taking into account both conductor and dielectric losses through a straightforward version of the perturbation method. The electromagnetic coupling as a function of the distance between NRD guide and resonators has been evaluated through proper extensions of typical lumped equivalent circuits, thus quantifying resonance frequency shifts, external and loaded quality factors, etc.. To validate the derived theoretical models, suitable measurements of all these parameters have been performed at microwaves on X-band NRD prototypes. 相似文献
119.
The erroneous perception of 2 objects when 1 object is touched with crossed fingers has been explained as an inability of the brain to correctly perceive the crossed fingers' positions. This account was examined in Exp I, in which the perceived position of stimuli touching the crossed fingers was mapped in 16 adult volunteers. Crossing the 3rd finger over the 4th displaced the perceived stimulus position counterclockwise; crossing the 3rd under the 4th displaced perceptions clockwise. In Exp II, perceived positions among 6 adults were found to fit a model of tactile saturation past the point of the functional range of action of the fingers. It is concluded that tactile stimuli are always perceived as if fingers were uncrossed and that spatial mapping is present only within the functional range of finger excursion. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
120.
Two motor acts were analyzed at the level of tongue and fingers. These motor acts generated illusions. When subjects voluntarily rotated the tongue by 90°, the perceived orientation of a tactile stimulus applied to the tongue did not covary with the perceived orientation of the tongue itself. Analogously, when subjects voluntarily crossed two adjacent fingers, the perceived position of two tactile stimuli applied to the fingers did not covary with the perceived position of the fingers themselves. Although tongue and fingers were positioned accurately in space, a lack of perceptual constancy occurred for tactile stimuli applied to these body parts. Therefore, whereas position sense was preserved, correct localization of objects was lost. The occurrence of this perceptual dissociation suggests that spatial localization of tactile stimuli may be independent both of knowledge of body part location and motor activity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献