5,784 research outputs found
Internal conductance under different light conditions along the plant profile of Ethiopian mustard (Brassica carinata A. Brown.)
This study focused on the internal conductance (g i ) along the plant profile of Ethiopian mustard under two light conditions: (i) light from the top only (I1); (ii) light from the top integrated by supplementary lateral light along the whole plant profile (I2). Lateral light strongly increased the productivity (e.g. +104% of seed oil) and net photosynthesis (A). The latter appeared more driven by g i (r=0.78 ** ) than by stomatal conductance (g s ) (r=0.51 * ). Importantly, irradiance also considerably shortened the time from leaf appearance to senescence, which means that corresponding leaves in I1 and I2 had different ages. Therefore, since leaf age and irradiance have counteracting effects on g i , I1 sometimes showed higher g i values than I2. With respect to irradiance, leaf age had clearly higher effects on g i , which radically declined from the top to the basal leaves, even under constant light conditions. The internal conductance caused a significant drawdown of CO 2 from the sub-stomatal cavity (C i ) to the site of carboxylation (C c ) that, in turn, led to a substantial underestimation of V cmax calculated using the A/C i model. Again, the trends of g i and g s were not consistent along the plant profile, and so the ratio between stomatal and internal limitations to A changed from top to bottom leaves, accordingly. This study suggests that g i may be a valuable trait for increasing photosynthetic capacity and productivity; nonetheless, it suggests caution in selecting leaves for high g i , as the latter can considerably change along the plant profile due to leaf age and irradiance effects
Image Guided Reconstruction of Un-sampled Data: A Filling Technique for Cultural Heritage Models
n/
Metodo di Hole Filling su mesh poligonali mediante proiezione di pattern laser
Il lavoro si colloca nel settore della Computer Graphics (più precisamente della scansione e ricostruzione 3D) e presenta una metodologia per il completamento di scansioni parziali mediante proiezione di pattern sugli oggetti originali. Una delle problematiche della scansione laser è la presenza di buchi nei modelli 3D prodotti. Tali mancanze sono dovute in genere alla presenza di superfici difficilmente raggiungibili con uno scanner, o a campagne di acquisizione non accurate. Le metodologie automatiche di chiusura di questi artefatti possono introdurre geometria non reale nel caso di buchi di grandi dimensioni. Il sistema proposto utilizza un pattern laser predefinito proiettato sull’oggetto reale: tramite l’allineamento di alcune immagini di questo pattern sul modello 3D di partenza, è possibile ricostruire parte della geometria: in questo modo il buco viene suddiviso in una serie di buchi più piccoli, chiudibili con minore rischio di creazione di artefatti. La ricostruzione della geometria è ottenuta tramite l'analisi della distorsione che i pattern disegnano sulla superficie. L'approccio è stato implementato nell'ambito di un'applicazione semiautomatica: questo permette il completamento di scansioni parziali in pochi minuti.
The proposed work stands in the research field of Computer Graphics (regarding in particular 3D scanning and geometry reconstruction). It presents a methodology for the completion of partial 3D models using a laser pattern projected on the real object. One of the issues in the field of 3D Scanning is the presence of holes in the final 3D models. This is usually due either to the fact that some parts of the surface are hard to reach by the scanner, or to an inaccurate scanning campaign. Automatic hole filling methods could fail in the case of bigger holes: the main risk is the creation of non existing geometry. The proposed system uses a pre-defined laser pattern which is projected on the real object. The alignment of some images depicting the pattern projected on the model permits to reconstruct part of the original geometry. Hence, the “big hole” problem is subdivided in a series of “small holes” problems, where the risk of creating artifacts is much smaller. Geometry reconstruction is obtained via the analysis of the distortion of the pattern projected on the object. The approach has been implemented in the context of a semiautomatic tool which permits to complete the geometry reconstruction in a few minutes
Building a Bio-Event Annotated Corpus for the Acquisition of Semantic Frames from Biomedical Corpora
This paper reports on the design and construction of a bio-event annotated corpus which was developed with a specific view to the acquisition of semantic frames from biomedical corpora. We describe the adopted annotation scheme and the annotation process, which is supported by a dedicated annotation tool. The annotated corpus contains 677 abstracts of biomedical research article
Abnormal Glucose Tolerance Is Associated with a Reduced Myocardial Metabolic Flexibility in Patients with Dilated Cardiomyopathy
Dilated cardiomyopathy (DCM) is characterized by a metabolic shift from fat to carbohydrates and failure to increase myocardial glucose uptake in response to workload increments. We verified whether this pattern is influenced by an abnormal glucose tolerance (AGT). In 10 patients with DCM, 5 with normal glucose tolerance (DCM-NGT) and 5 with AGT (DCM-AGT), and 5 non-DCM subjects with AGT (N-AGT), we measured coronary blood flow and arteriovenous differences of oxygen and metabolites during Rest, Pacing (at 130 b/min), and Recovery. Myocardial lactate exchange and oleate oxidation were also measured. At Rest, DCM patients showed a reduced nonesterified fatty acids (NEFA) myocardial uptake, while glucose utilization increased only in DCM-AGT. In response to Pacing, glucose uptake promptly rose in N-AGT (from 72 ± 21 to 234 ± 73 nmol/min/g, p<0.05), did not change in DCM-AGT, and slowly increased in DCM-NGT. DCM-AGT sustained the extra workload by increasing NEFA oxidation (from 1.3 ± 0.2 to 2.9 ± 0.1 mol/min/gO2 equivalents, p<0.05), while DCM-NGT showed a delayed increase in glucose uptake. Substrate oxidation rates paralleled the metabolites data. The presence of AGT in patients with DCM exacerbates both the shift from fat to carbohydrates in resting myocardial metabolism and the reduced myocardial metabolic flexibility in response to an increased workload. This trial is registered with ClinicalTrial.gov NCT02440217
Covalent capture of oriented calix[6]arene rotaxanes by a metal-free active template approach
We describe the active template effect of a calix[6]arene host towards the alkylation of a complexed pyridylpyridinium guest. The acceleration of the reaction within the cavity is significant and rim-selective, enabling the efficient preparation of rotaxanes with full control of the mutual orientation of their nonsymmetric components
Sentences and Documents in Native Language Identification
Starting from a wide set of linguistic features, we present the first in depth feature analysis in two different Native Language Identification (NLI) scenarios. We compare the results obtained in a traditional NLI document classification task and in a newly introduced sentence classification task, investigating the different role played by the considered features. Finally, we study the impact of a set of selected features extracted from the sentence classifier in document classification.Partendo da un ampio insieme di caratteristiche linguistiche, presentiamo la prima analisi approfondita del ruolo delle caratteristiche linguistiche nel compito di identificazione della lingua nativa (NLI) in due differenti scenari. Confrontiamo i risultati ottenuti nel tradizionale task di NLI ed in un nuovo compito di classificazione di frasi, studiando il ruolo differente che svolgono le caratteristiche considerate. Infine, studiamo l’impatto di un insieme di caratteristiche estratte dal classificatore di frasi nel task di classificazione di documenti
PaCCSS-IT: A Parallel Corpus of Complex-Simple Sentences for Automatic Text Simplification
In this paper we present PaCCSS-IT, a Parallel Corpus of Complex-Simple Sentences for ITalian. To build the resource we develop a new method for automatically acquiring a corpus of complex-simple paired sentences able to intercept structural transformations and particularly suitable for text simplification. The method requires a wide amount of texts that can be easily extracted from the web making it suitable also for less-resourced languages. We test it on the Italian language making available the biggest Italian corpus for automatic text simplification
Validation tests of the CMS TIB/TID structures
Tracker Inner Barrel half-cylinders and Tracker Inner Disks of the CMS tracker have been integrated in three INFN sites. Integrated structures are submitted to an extensive set of tests whose main aim is to validate the functioning of the structures in CMS-like conditions. The tests have furthermore proven to be a great opportunity to study several aspects of the performance in detail. In this note the tests are described in some detail and an overview of the results is presented
Plasmon-enhanced circular dichroism spectroscopy of chiral drug solutions
We investigate the potential of surface plasmon polaritons at noble metal
interfaces for surface-enhanced chiroptical sensing of dilute chiral drug
solutions with nano-litre volume. The high quality factor of surface plasmon
resonances in both Otto and Kretschmann configurations enables the enhancement
of circular dichroism thanks to the large near-field intensity of such
plasmonic excitations. Furthermore, the subwavelength confinement of surface
plasmon polaritons is key to attain chiroptical sensitivity to small amounts of
drug volumes placed around 100 nm by the metal surface. Our
calculations focus on reparixin, a pharmaceutical molecule currently used in
clinical studies for patients with community-acquired pneumonia, including
COVID-19 and acute respiratory distress syndrome. Considering realistic dilute
solutions of reparixin dissolved in water with concentration 5 mg/ml and
nl volume, we find a circular-dichroism differential absorption enhancement
factor of the order 20 and chirality-induced polarization distortion
upon surface plasmon polariton excitation. Our results are relevant for the
development of innovative chiroptical sensors capable of measuring the
enantiomeric imbalance of chiral drug solutions with nl volume
- …