5,047 research outputs found
The acquisition of English L2 prosody by Italian native speakers: experimental data and pedagogical implications
This paper investigates Yes-No question intonation patterns in English L2, Italian L1, and
English L1. The aim is to test the hypothesis that L2 learners may show different
acquisition strategies for different dimensions of intonation, and particularly the
phonological and phonetic components. The study analyses the nuclear intonation
contours of 4 target English words and 4 comparable Italian words consisting of sonorant
segments, stressed on the semi-final or final syllable, and occurring in Yes-No questions
in sentence-final position (e.g., Will you attend the memorial?, Hai sentito la Melania?).
The words were contained in mini-dialogues of question-answer pairs, and read 5 times
by 4 Italian speakers (Padova area, North-East Italy) and 3 English female speakers
(London area, UK). The results show that: 1) different intonation patterns may be used to
realize the same grammatical function; 2) different developmental processes are at work,
including transfer of L1 categories and the acquisition of L2 phonological categories.
These results suggest that the phonetic dimension of L2 intonation may be more difficult
to learn than the phonological one
CT-based tumour response criteria compared after combined treatment for liver metastases of colorectal cancer
open6noPurpose: The aim of this analysis is to compare different tumour response
criteria (TRC) after chemotherapy combined with bevacizumab in liver
metastases from colorectal cancer (mCRC) to ascertain the best early
prognostic indicator of response.
Methods and Materials: 103 target liver metastases from 65 mCRC patients
treated with chemoterapy plus bevacizumab were examined at the Istituto
Oncologico Veneto IOV-IRCSS (March 2008-January 2013). All patients had
baseline CT and at least one follow-up scan. Tumour response was
retrospectively analyzed by two radiologists using RECIST1.1, modified Choi,
and Chun morphologic criteria. Tumour response, classified as good (complete
or partial response) or poor (stable or progressive disease), was compared
with progression-free survival (PFS) at first follow-up (t1) and time of best
response. Interobserver agreement and concordance between TRC were
measured.
Results: At t1, 32.31% showed a good response according to RECIST1.1
(median PFS 11.1), 84.62% according to Choi (median PFS 10.8). These
percentages rose to 49.23% (median PFS 12.1) and 87.69% (median PFS
10.8), respectively, at the time of best response. According to Chun, 67.69%
showed a good response at the time of best response (median PFS 10.8). The
Choi criteria detected a higher proportion of good responders at t1, showing a
better correlation with PFS; all methods correlated with PFS at the time of best
response.
Conclusion: The Choi criteria proved more consistent in the early detection of
response in mCRC treated with chemotherapy plus bevacizumab,
underscoring the importance of using these criteria in the early assessment of
response to combined treatment.openopenVarotto, A.; Di Grazia, L.; Aliberti, C.; Bergamo, F.; Nardin, M.; Pomerri, F.Varotto, A.; Di Grazia, L.; Aliberti, C.; Bergamo, F.; Nardin, M.; Pomerri, Fabi
The Vehicle Routing Problem with Divisible Deliveries and Pickups
The vehicle routing problem with divisible deliveries and pickups is a new and interesting model within
reverse logistics. Each customer may have a pickup and delivery demand that have to be served with
capacitated vehicles. The pickup and the delivery quantities may be served, if beneficial, in two separate visits.
The model is placed in the context of other delivery and pickup problems and formulated as a mixed-integer
linear programming problem. In this paper, we study the savings that can be achieved by allowing the pickup
and delivery quantities to be served separately with respect to the case where the quantities have to be served
simultaneously. Both exact and heuristic results are analysed in depth for a better understanding of the problem
structure and an average estimation of the savings due to the possibility of serving pickup and delivery
quantities separately
Structure and electronic properties of the quasi-one-dimensional BaâCoâââZnâSâ series
This work focuses on the structure and physical properties of the solid solution BaâCoâââZnâSâ (0 †x †1), a family of quasi-one-dimensional sulfides with end members BaâCoSâ and BaâZnSâ. The structure of selected compounds with increasing ZnÂČâș content has been analysed using, neutron diffraction, TEM and EXAFS and the physical properties via magnetic susceptibility and resistivity measurements. The progressive substitution of the non-magnetic ZnÂČâș cation for CoÂČâș rapidly destroys the antiferromagnetic transition present at 46 K in the quasi one-dimensional BaâCoSâ, leading to paramagnetic behaviour down to the lowest investigated temperature (5K) for compounds with x > 0.25. For compounds with x â„ 0.4, a pure CW regime is recovered around 300 K, yielding effective moments consistent with the g factor of the tetrahedrally coordinated CoÂČâș previously determined for BaâCoSâ. The ZnÂČâș/CoÂČâș substitution also removes the metallic-like behaviour of BaâCoSâ causing an increase in the value of the resistivity with all the BaâCoâââZnâSâ compounds showing semiconducting behaviour. The negative magnetoresistance of BaâCoSâ is improved by the ZnÂČâș/CoÂČâș substitution, with values of â 6% for BaâCoâ.ââ
Znâ.ââ
Sâ, â 9% for BaâCoâ.â
Znâ.â
Sâ and â 8% for BaâCoâ.ââ
Znâ.ââ
Sâ. However, there does not seem to be a correlation between the values of the resistivity and the magnetoresistance and the content of ZnÂČâș, leading to the hypothesis that transport properties may be linked more closely to extrinsic properties
Altruism and Gender in the Trust Game
2This paper analyses gender differences in the trust game. Our experiment implements the triadic design proposed by Cox (2004) to discriminate between transfers resulting from trust or trustworthiness and transfers resulting from altruistic preferences. We observe that women exhibit a higher degree of altruism than men for both trust and trustworthiness but relatively more for trustworthiness. This result provides an explanation to the experimental finding that women reciprocate more than men.reservedmixedA. INNOCENTI; MARIA GRAZIA PAZIENZAInnocenti, Alessandro; MARIA GRAZIA, Pazienz
Improving biological production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) co-polymer: a critical review
AbstractAlthough poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is the most promising biopolymer for petroleum-based plastics replacement, the low processes productivity as well as the high sale price represent a major barrier for its widespread usage. The present work examines comparatively the existing methods to enhance the yield of the PHBV co-polymer biologically produced and/or reduce their costs. The study is addressed to researchers working on the development of new biological production methods and/or the improvement of those currently used. At this aim, the authors have considered the analysis of some crucial aspects related to substrates and microorganism's choice. The production strategies have been individuated, presented and discussed, either based on a single aspect (type of substrate or microorganism) or based on combined aspects (type of substrate and microorganism). Process operating conditions have been discussed as well. The analysis indicates that the addition of 3HV precursors is capable to dramatically enhance the hydroxyvalerate fraction in the produced biopolymers. On the other hand, due to the high costs of the 3HV precursors, the utilization of wild bacterial species capable to produce the hydroxyvalerate fraction from unrelated carbon sources (i.e. no 3HV precursors) also can be considered a valuable strategy for costs reduction. Moreover, metabolic engineering techniques can be successfully used to promote 3HV precursors-independent biosynthesis pathways and enhance the process productivity. The use of mixed cultures or extremophile bacteria avoids the need of sterile working conditions, and therefore favours the process scale-up. The utilization of the organic waste as substrate plays a key role for a sharp reduction of production costs. Finally, the selection of the most suitable substrate-microorganism combination cannot be separated by the adoption of an appropriate choice of reactor configuration and abiotic factors.
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