2,965 research outputs found
Rigenerazione e trasformazione mediata da A. Tumefaciens di una varietà di pesco Big Top e portinnesto GF677 per indurre la resistenza al virus della vaiolatura delle drupacee (PPU) con costrutti che inducono il silenziamento genico post-trascrizionale
No full textLe produzioni frutticole rappresentano un’importante settore produttivo per il mercato dell’area del Mediterraneo. Questo risulta spesso essere penalizzato da problemi di carattere fitopatologico con consistenti ripercussioni sulla produzione, sulla qualità e nei relativi costi. La trasformazione genetica di piante da frutto offre enormi potenzialità per il miglioramento della produzione, della qualità e per l’ottenimento di cultivar con maggiore resistenza ai patogeni.
Lo scopo della ricerca è stato quello di sviluppare efficienti protocolli di trasformazione e rigenerazione da applicare ad una varietà ed ad un portainnesto di pesco. La trasformazione genetica è stato effettuata adattando ed ottimizzando il metodo già sviluppato su due cultivar di uva da tavola (Thompson senza semi e Silcora) da Mezzetti nel 2002. Questo metodo si basa sulla produzione in vitro di ammassi meristematici ad elevata capacità di differenziare i germogli avventizi tramite organogenesi. Da questi ammassi vengono preparate delle piccole fettine da utilizzare per la trasformazione mediata da Agrobacterium tumefaciens di una varietà di pesco (Big Top) e di un portainnesto (GF677). La selezione dei putativi transgenici è stata eseguita su appropriati substrati, contenenti l’agente di selezione (Kanamicina) a concentrazioni crescenti (50 mg l-1, 75 mg l-1 and 100 mg l-1). I tessuti in selezione ogni 20 giorni ( due passaggi per ogni concentrazione) sono stati trasferiti su nuovi substrati al fine di ottenere una selezione più efficiente.
Il metodo ha previsto l’utilizzato di costrutti genici che inducono il silenziamento genico post-trascrizionale al fine di indurre la resistenza al virus (PPV) e studiarne la funzione genetica. Inoltre per velocizzare la fase di screening dei germogli ed osservarne il loro sviluppo in vitro, durante le fasi di selezione, sono state effettuate delle trasformazioni utilizzando un nuovo costrutto sfruttante la capacità della proteina fluorescente verde (GFP).
Dopo aver effettuato le analisi molecolari (PCR) e lo screening con UV non sono risultate piante trasformate anche se con il costrutto (GFP) 4 linee sono risultate positive alle analisi PCR utilizzando la coppia di primer disegnati sul gene nptII ma nessuna utilizzando la coppia di primer disegnati sul gene della GFP
An assessment of the impact of possible CAP reform scenarios on Romanian agriculture
No full textUsing 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,
Rich, Sturmian, and trapezoidal words
No full textIn 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
Regeneration and genetic transformation via-organogenesis of different varieties of Vitis vinifera and Prunus persica
No full textThe genetic transformation of fruit trees provides
huge potentiality for the improvement of fruit production and quality
and for the obtainment of cultivars with increased resistance to
pathogens. Furthermore, efficient methods of fruit trees transformation
would facilitate functional genomic studies. The aim of the
research is to develop efficient regeneration and genetic transformation
protocols to be applied to different varieties of table and
wine grapes and to varieties and rootstock of peach
Peach (Prunus Persica L.)
No full textUntil now, the application of genetic transformation techniques in peach has been limited by the difficultiesin developing efficient regeneration and transformation protocols. Here we describe an efficient regenerationprotocol for the commercial micropropagation of GF677 rootstock (Prunus persica × Prunusamygdalus).The method is based on the production, via organogenesis, of meristematic bulk tissues characterizedby a high competence for shoot regeneration.This protocol has also been used to obtain GF677 plants genetically engineered with an empty hairpincassette (hereafter indicated as hp-pBin19), through Agrobacterium tumefaciens-mediated transformation.After 7–8 months of selection on media containing kanamycin, we obtained two genetically modifiedGF677 lines. PCR and Southern blot analyses were performed to confirm the genetic status
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
A General Formulation to Describe Empirical Rainfall Thresholds for Landslides
No full textAbstractIn this paper, a brief description of the Generalized FLaIR Model (GFM, De Luca and Versace, 2016) is provided, that is able to reproduce all the empirical thresholds proposed in literature, aimed to forecast landslides triggered by rainfall. In particular, this paper focuses on Antecedent Precipitation (AP) schemes. The paper demonstrates that these are particular solutions of the GFM and will exemplify this using AP schemes for NE Italy1, Seattle2 and Nicaragua - El Salvador3
The technological specialization of countries : an analysis of patent data
No full textNew methods of analysis of patent statistics allow assessing country profiles of technological specialization for the period 1990-2006. We witness a modest decrease in levels of specialization, which we show to be negatively influenced by country size and degree of internationalization of inventive activities
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