2,976 research outputs found
Characterization of autochtonous Walnut germplasm in Fiuli Venezia Giulia
No full textJuglans regia is mostly distributed in the temperate and subtropical regions of the Northern Hemisphere. During the last ice age, the species survived only in refugial areas. In Europe it survived in the Italian and Balkan peninsulas. Friuli Venezia Giulia is the natural corridor where the two populations met during the re-colonization after the glaciation. In the present study 220 autochtonous accessions were sampled and georeferenced and a genetic analysis with 20 microsatellite loci taken from the literature was carried out. The local population shows a moderate genetic diversity and can be classified in two clusters. The first one shows a great mixture between genotypes coming from different areas, even particularly far away from each other. To this first cluster belongs the vast majority of the samples. The second cluster consist of three genotypes originated from an import of Walnuts from Russia at the beginning of the XX century.
On the genotypes that during the investigation produced enough fruits carpometric analysis were performed. The best accessions were included in a ranking list compiled using a multivariate analysis considering all the traits valuable for breeding and selection, such as nut weight, kernel weight, shell thickness, kernel skin colour, ease of kernel extraction and fruit appearance. These best accessions will either be selected as they are for vegetative propagation or employed in breeding programs.
For every genotype that produced fruits the oil content and its acidic spectrum were determined. Both turned out not to be influenced by the year of sampling. The studied wild walnut trees shown a significant linear relationship and a positive relationship between the minimum daily temperature and the oleic acid content. Many of the accessions could be used in breeding programs for the selections of cultivars with high oil contents and with differentiated acidic spectra, depending on the purpose of the oil.
The last part of the investigation was about the diffusion in Friuli Venezia Giulia of two non-local walnut pests come from America, a leafminer belonging to the genus Coptodisca and the carpophagous Rhagoletis completa.
Coptodisca lucifluella has been found in 55 out of the 219 considered sites. This is the first report of the species for the region. The species has been identified not only by typical leaf symptoms but also by means of mitochondrial DNA barcode. The DNA sequences were submitted to Genebank. The level of pest infestation in Friuli Venezia Giulia resulted lower than in other Italian areas and its diffusion was negatively correlated with the altitude. The species was observed in sites above 600 m a.s.l. The low infestation observed could be associated with the activity of native natural enemies, as parasitoids of the genus Chrysocharis (Hymenoptera, Encyrtidae) that were observed into the mines. Rhagoletis completa was found in 89 out of the 185 walnut trees with fruits. In many sites, especially in lowland localities, the infestation level was very high, as to suggest treatments with insecticides. The level of infestation decreased with altitude: at sites above 700 m a.s.l. either there was no infestation or the infestation was very low. No correlation has been found between the average weight of the fruits and the level of infestation
Kernel oil content and oil composition in walnut (Juglans regia L.) accessions from north-eastern Italy
No full textBACKGROUND:Walnut oil use is currently limited by its poor oxidative stability due to the high percentage of polyunsaturated
fatty acids. Modifying the oil composition may be a goal in walnut breeding to increase interest in this crop. Exploring natural
variability and identifying the main environmental factors affecting oil quality are necessary in crop selection. Therefore 190
wild accessions were collected and evaluated during 2013 and 2014 for oil content and its fatty acid profile and compared with
five commercial cultivars as references.
RESULTS: High variation inkerneloil content andfatty acid compositionwas foundin thenativewalnut.Kerneloil content ranged
from 54.2 to 72.2% (w/w). The major fatty acids were linoleic (range 46.9–68.6%), oleic (10.0–25.1%), linolenic (6.9–17.6%),
palmitic (3.9–11.4%) and stearic (1.1–5.2%) acids. Some accessions had oil with a fatty acid ratio very different from the
reference commercial cultivars, especially the oleic acid/polyunsaturated fatty acid (PUFA) ratio. A significant linear relationship
and positive correlation between the daily minimum temperature and oleic acid content was observed in the wild walnuts.
CONCLUSION: The wide variation in fatty acid content and composition allows superior accessions to be selected for diffusion
among growers. A suitable strategy would be to make a selection against PUFA content rather than just for high oleic acid.
In addition, the selected high oleic accessions, before being utilized per se or as donor parents in breeding programs, have to
demonstrate they are not adversely affected by the environment
Morphological and carpological variability of walnut germplasm (Juglans regia L.) collected in North-eastern Italy and selection of superior genotypes
No full textNuts collected from wild accessions of Persian walnut (Juglans regia L.) in the Friuli Venezia Giulia region (North Eastern Italian Alps) were evaluated during 2013–2015. The analyses carried out were mainly on fruit traits, the only morphological traits that could be observed and statistically analysed, being less dependent on the area of sampling, considering geographic features such as altitude, slope, soil, and climate. Such fruit traits proved to be very variable. The nut weight ranged from 2.2 to 17.3 g, the shell thickness from 0.35 to 2.30 mm, the color of kernel skin from light to amber. The fruit nut appearance, evaluated by a panel of consumers, varied from 2.50 to 6.83 in a scale from 0 (very bad) to 10 (very attractive). A multivariate analysis carried out considering traits valuable for breeding and selection, such as nut weight, kernel weight: nut weight ratio, shell thickness, kernel color, and fruit appearance, produced a ranking list, that included, at best, accessions that could be either selected as such for vegetative propagation and distribution to growers or used in breeding programs. A disadvantage of these selections is their terminal bearing habit which is not appreciated by breeders, who prefer the most productive genotypes with lateral bearing habit
An assessment of the impact of possible CAP reform scenarios on Romanian agriculture
Get PDFUsing a simplified model, with key-variable the prices of two different possible scenarios of CAP reform after 2013 (moderate and radical), this paper present a comparison between the price effects of implementation of each reform scenario at 2015 horizon on Romanian agriculture. This short analysis shows that, under the presented hypotheses, the net welfare effect, due to the price changes, for the selected products, is positive in both reform scenarios, yet greater in the case of the radical reform. Integrated in the large context of Romanian development, it seems that the influence of CAP reform upon agriculture and rural areas will be most likely a gradual one: an interpenetration between the two scenarios is foreseeable, starting with the moderate reform that will dominate the period around 2013, the reform measures acquiring a more radical character afterwards.CAP reform, Romania, welfare effects, Agricultural and Food Policy,
Altitude affects the distribution and abundance of two non-native insect pests of the common walnut
No full textThe leaf miner Coptodisca lucifluella and the carpophagous Rhagoletis completa, of American origin, are two non‐native walnut (Juglans spp.) pests in Italy. For the Friuli Venezia Giulia region (FVG) (N‐E Italy), C. lucifluella is not yet listed, while R. completa has been present for over 25 years. During 2015, samples of leaves and fruits were collected from 219 single old common walnut trees (Juglans regia) placed at different altitudes (0–1,073 m a.s.l.) in FVG to detect the distribution and abundance of both pests. Samples of leaf miner larvae and their parasitoids were subjected to mitochondrial DNA analysis for identification. C. lucifluella has been found in 55 out of 219 sites. The species has been identified by typical leaf symptoms and by its DNA barcode. This is the first report of the species for FVG. The leaf miner distribution was negatively correlated with altitude. The species has not been observed at sites over 600 m a.s.l. Larvae were parasitized by native parasitoids identified as belonging to the genus Chrysocharis by morphological features and by DNA barcode. R. completa has been found in 89 out of 165 sites on walnut trees with fruits. The infestation level was very high in lowland localities. At sites over 700 m a.s.l., no infestation was found. Both species are widespread in the region, and their occurrence is significantly affected by altitude. Data suggest that walnut trees could be cultivated in some mountain areas without the need to control R. completa with insecticides
Rich, Sturmian, and trapezoidal words
Get PDFIn this paper we explore various interconnections between rich words, Sturmian words, and trapezoidal words. Rich words, first introduced by the second and third authors together with J. Justin and S. Widmer, constitute a new class of finite and infinite words characterized by having the maximal number of palindromic factors. Every finite Sturmian word is rich, but not conversely. Trapezoidal words were first introduced by the first author in studying the behavior of the subword complexity of finite Sturmian words. Unfortunately this property does not characterize finite Sturmian words. In this note we show that the only trapezoidal palindromes are Sturmian. More generally we show that Sturmian palindromes can be characterized either in terms of their subword complexity (the trapezoidal property) or in terms of their palindromic complexity. We also obtain a similar characterization of rich palindromes in terms of a relation between palindromic complexity and subword complexity
Characterization Results for the Poset Based Representation of Topological Relations - I: Introduction and Models
No full text@article{DBLP:journals/informaticaSI/ForlizziN99,
author = {Luca Forlizzi and
Enrico Nardelli},
title = {Characterization Results for the Poset Based Representation
of Topological Relations - I: Introduction and Models.},
journal = {Informatica (Slovenia)},
volume = {23},
number = {2},
year = {1999},
bibsource = {DBLP, http://dblp.uni-trier.de}
Characterization Results for the Poset Based Representation of Topological Relations - II: Intersection and Union
No full text@article{DBLP:journals/informaticaSI/ForlizziN00,
author = {Luca Forlizzi and
Enrico Nardelli},
title = {Characterization Results for the Poset Based Representation
of Topological Relations - II: Intersection and Union.},
journal = {Informatica (Slovenia)},
volume = {24},
number = {1},
year = {2000},
bibsource = {DBLP, http://dblp.uni-trier.de}
System-on-chip Computing and Interconnection Architectures for Telecommunications and Signal Processing
No full textThis dissertation proposes novel architectures and design techniques targeting SoC building blocks for telecommunications and signal processing applications.
Hardware implementation of Low-Density Parity-Check decoders is approached at both the algorithmic and the architecture level. Low-Density Parity-Check codes are a promising coding scheme for future communication standards due to their outstanding error correction performance.
This work proposes a methodology for analyzing effects of finite precision arithmetic on error correction performance and hardware complexity. The methodology is throughout employed for co-designing the decoder. First, a low-complexity check node based on the P-output decoding principle is designed and characterized on a CMOS standard-cells library. Results demonstrate implementation loss below 0.2 dB down to BER of 10^{-8} and a saving in complexity up to 59% with respect to other works in recent literature. High-throughput and low-latency issues are addressed with modified single-phase decoding schedules. A new "memory-aware" schedule is proposed requiring down to 20% of memory with respect to the traditional two-phase flooding decoding. Additionally, throughput is doubled and logic complexity reduced of 12%. These advantages are traded-off with error correction performance, thus making the solution attractive only for long codes, as those adopted in the DVB-S2 standard. The "layered decoding" principle is extended to those codes not specifically conceived for this technique. Proposed architectures exhibit complexity savings in the order of 40% for both area and power consumption figures, while implementation loss is smaller than 0.05 dB.
Most modern communication standards employ Orthogonal Frequency Division Multiplexing as part of their physical layer. The core of OFDM is the Fast Fourier Transform and its inverse in charge of symbols (de)modulation. Requirements on throughput and energy efficiency call for FFT hardware implementation, while ubiquity of FFT suggests the design of parametric, re-configurable and re-usable IP hardware macrocells. In this context, this thesis describes an FFT/IFFT core compiler particularly suited for implementation of OFDM communication systems. The tool employs an accuracy-driven configuration engine which automatically profiles the internal arithmetic and generates a core with minimum operands bit-width and thus minimum circuit complexity. The engine performs a closed-loop optimization over three different internal arithmetic models (fixed-point, block floating-point and convergent block floating-point) using the numerical accuracy budget given by the user as a reference point. The flexibility and re-usability of the proposed macrocell are illustrated through several case studies which encompass all current state-of-the-art OFDM communications standards (WLAN, WMAN, xDSL, DVB-T/H, DAB and UWB). Implementations results are presented for two deep sub-micron standard-cells libraries (65 and 90 nm) and commercially available FPGA devices. Compared with other FFT core compilers, the proposed environment produces macrocells with lower circuit complexity and same system level performance (throughput, transform size and numerical accuracy).
The final part of this dissertation focuses on the Network-on-Chip design paradigm whose goal is building scalable communication infrastructures connecting hundreds of core. A low-complexity link architecture for mesochronous on-chip communication is discussed. The link enables skew constraint looseness in the clock tree synthesis, frequency speed-up, power consumption reduction and faster back-end turnarounds. The proposed architecture reaches a maximum clock frequency of 1 GHz on 65 nm low-leakage CMOS standard-cells library. In a complex test case with a full-blown NoC infrastructure, the link overhead is only 3% of chip area and 0.5% of leakage power consumption.
Finally, a new methodology, named metacoding, is proposed. Metacoding generates correct-by-construction technology independent RTL codebases for NoC building blocks. The RTL coding phase is abstracted and modeled with an Object Oriented framework, integrated within a commercial tool for IP packaging (Synopsys CoreTools suite). Compared with traditional coding styles based on pre-processor directives, metacoding produces 65% smaller codebases and reduces the configurations to verify up to three orders of magnitude
Il Progetto Ecumene: strumenti descrittivi per beni culturali di ambito archivistico e storico artistico
No full textIl progetto Ecumene ha come obiettivo la realizzazione di strumenti tecnologici per la fruizione integrata, attraverso il web, di descrizioni afferenti a diversi settori disciplinari del mondo dei beni culturali. L’approfondimento delle tematiche di integrazione fra descrizioni di beni culturali diversi è stato affrontato cercando di indagare, in primo luogo, gli aspetti di rappresentazione concettuale specifici, all’interno dei settori disciplinari prescelti, attraverso una panoramica riferita alla situazione sia italiana che internazionale. L’indagine ha assunto un punto di vista particolare, ritenuto rispondente all’impostazione ed alle finalità generali di Ecumene, restringendo la propria attenzione alle rappresentazioni utilizzate nel contesto di strumenti informatici . In accordo con tale criterio si è identificata una significativa distinzione fra modelli e strumenti finalizzati al rilevamento di informazioni, cioè alla loro acquisizione e memorizzazione digitalizzata, e modelli e strumenti finalizzati alla comunicazione di quelle stesse informazioni. i Dopo aver esaminato i passaggi fondamentali del processo di definizione di un approccio all’integrazione fra descrizioni di beni culturali di diversa tipologia, basato sulla condivisione del contesto, si descrive la realizzazione di un ambiente integrato di fruizione, nell'ambito del progetto Ecumene, partendo dalle potenzialità del modello descrittivo basato sulla condivisione di contesto e sfruttandone le caratteristiche di affinità con gli strumenti per l’implementazione della banca dati per mezzo di schemi Entità-Relazioni
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