3,477 research outputs found
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
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
The unexpected influencer: Pope Francis and European perceptions of the recent refugee crisis
No full textThis article analyses the impact of non-informative communication on Europeans' perceptions of European Union (EU) action on the issue of migration. We exploit the fact that Pope Francis's visit to Lesbos Island in 16 April 2016, overlaps with the days of the interviews for a Special Eurobarometer survey, such that some respondents were unintentionally exposed to the Pope's speech while others were not. Comparing Catholics and non-Catholics before and after the Pope's visit in a difference-in-differences setting, we show that the papal message persuaded exposed Catholic individuals that EU action on the issue of migration is insufficient. The effect is temporary and varies according to the demographic characteristics of the respondents and by the country's share of asylum applicants in 2015. Moreover, media exposure of the Pope's visit, measured by the Global Database of Events, Language, and Tone, was greater in Catholic countries, and this might explain the effect found
DOWN-REGULATION OF HEPATIC MBOAT7 BY HYPERINSULINEMIA FAVORS STEATOSIS DEVELOPMENT
No full textBackground and aims: Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver diseases in Western Countries. NAFLD could evolve into nonalcoholic steatohepatitis (NASH), which is associated with activation of fibrogenesis, possibly leading to cirrhosis and hepatocellular carcinoma (HCC). The genetic background plays a pivotal role in predisposing to development and progression of liver disease. Recently, our group have shown that the rs641738 C>T variant, in the Membrane bound o-acyltransferase domain-containing 7 locus (MBOAT7), increases the risk of NAFLD, NASH and fibrosis, by decreasing the hepatic expression of MBOAT7, a protein involved in phosphatidylinositol acyl-chain remodeling. Aim of this study was to evaluate the regulation of hepatic MBOAT7 and the impact on hepatic fat accumulation.
Methods: We examined hepatic and adipose MBOAT7 expression in 119 obese patients and in experimental models. We silenced hepatic Mboat7 by i.v. administration of antisense oligonucleotides modified by morpholinos (MPO) for 4 consecutive days in C57Bl/6 male mice (n=6).
Results: In obese patients, hepatic mRNA levels of MBOAT7 progressively decreased from normal liver to simple steatosis and NASH (p<0.05). At multivariate analysis, type 2 diabetes (p<0.05), necroinflammation (p<0.01) and MBOAT7 genotype (p<0.01) were independently associated with MBOAT7 down-regulation. This suggests that down-regulation of hepatic MBOAT7 is involved in NAFLD pathogenesis independently of MBOAT7 genotype. In line with this hypothesis, we found that mRNA and protein levels of Mboat7 were reduced in experimental models of NAFLD: in the methionine-choline deficient diet (MCD), but more so in genetically obese Lepob/ob mice and in insulin resistant mice with Insulin receptor haplo-insufficiency (InsR+/-), characterized by hyperinsulinemia (p<0.05). Furthermore, in wild-type male mice Mboat7 was physiologically down-regulated by refeeding concomitantly with the rise of insulin levels and activation of hepatic insulin signaling through Phosphatidyl Inositol 3-Kinase (PI3K) and the Serine/Threonine Kinase AKT. In keeping with these results, activation of insulin-receptor dependent signaling down-regulated Mboat7 protein expression in primary mouse hepatocytes in a PI3Kinase-depedent manner. Consistently, in InsR+/- hepatocytes insulin-mediated suppression of Mboat7 was lost (p<0.01). Moreover, the effect of insulin on Mboat7 expression was also abrogated in wild-type hepatocytes treated with antisense oligonucleotide stabilized by morpholination directed against FoxO1 (MPO) (p<0.05). These data suggest that FoxO1 is required to mediate the Mboat7 regulation by insulin. Consistently with this notion, the hampered Mboat7 expression observed in InsR+/- hepatocytes was rescued by FoxO1-silencing by antisense-MPO (p<0.05 vs scramble). Finally, in vivo administration of antisense-MPO against Mboat7 for 4 consecutive days, induced a 45% silencing of hepatic Mboat7 in wild-type male mice, which is comparable to that associated with the genetic risk variant, resulting in 80% increase in hepatic TG content (p<0.05 vs scramble) and in microvesicular steatosis development. In contrast, it did not affect circulating glucose, insulin and lipid levels. Steatosis development was not explained by altered de novo lipogenesis or β-oxidation or VLDL export, but was associated with increased expression of fatty acids transporters (such as Fatp1, Fabp1). Conversely, Mboat7 silencing was not associated with alterations in the hepatic expression of inflammatory cytokines and chemokines (such as Tnf-α and Cxcl10). These data are consistent with human genetic data suggesting that MBOAT7 down-regulation plays a causal role in NAFLD development.
Conclusion: In summary, we found that hyperinsulinemia, a typical feature of metabolic syndrome and post-prandial conditions, reduces hepatic MBOAT7 expression via increased insulin signaling activation through the Insulin receptor - PI3K – FoxO1 pathway. Reduced MBOAT7 then favors hepatic fat accumulation. These data suggest that MBOAT7 down-regulation may be implicated in the pathogenesis of progressive NAFLD
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
Palindromic richness
No full textIn this paper, we study combinatorial and structural properties of a new class of finite and infinite words that are 'rich' in palindromes in the utmost sense. A characteristic property of the so-called rich words is that all complete returns to any palindromic factor are themselves palindromes. These words encompass the well-known episturmian words, originally introduced by the second author together with Droubay and Pirillo in 2001 [X. Droubay, J. Justin, G. Pirillo, Episturmian words and some constructions of de Luca and Rauzy, Theoret. Comput. Sci. 255 (2001) 539-553]. Other examples of rich words have appeared in many different contexts. Here we present the first unified approach to the study of this intriguing family of words. Amongst our main results, we give an explicit description of the periodic rich infinite words and show that the recurrent balanced rich infinite words coincide with the balanced episturmian words. We also consider two wider classes of infinite words, namely weakly rich words and almost rich words (both strictly contain all rich words, but neither one is contained in the other). In particular, we classify all recurrent balanced weakly rich words. As a consequence, we show that any such word on at least three letters is necessarily episturmian; hence weakly rich words obey Fraenkel's conjecture. Likewise, we prove that a certain class of almost rich words obeys Fraenkel's conjecture by showing that the recurrent balanced ones are episturmian or contain at least two distinct letters with the same frequency. Lastly, we study the action of morphisms on (almost) rich words with particular interest in morphisms that preserve (almost) richness. Such morphisms belong to the class of P-morphisms that was introduced by Hof, Knill, and Simon in 1995 [A. Hof, O. Knill, B. Simon, Singular continuous spectrum for palindromic Schrödinger operators, Comm. Math. Phys. 174 (1995) 149-159]
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