2,184 research outputs found
The real exchange rate process and its real effects: The cases of Mexico and the USA
Exchange rate management is a salient macroeconomic issue, especially in developing countries. In this paper, we study political economy factors that may affect the real exchange rate (RER) process and the real economic effects of the RER. We review recent literature on the effects of elections on the exchange rate, and adapt Ballâs (1992) model to show that uncertainty about the future course of policy may make more appreciated RERâs less predictable. We also review the literature on the real effect of RER appreciations and of RER uncertainty. We then construct a simultaneous GARCH-M model of the joint determination of the RER and output capable of testing our hypotheses simultaneously in a single model. We estimate the model using data first from Mexico, a developing country, and the US. In Mexico we find that elections significantly affect the evolution of the RER, that more appreciated RERs are less predictable, that RER depreciations lower output growth and that RER uncertainty lowers output growth, even when controlling for its wellstudied effect on trade. By contrast, none of these effects are found in the US data.real exchange rate volatility, economic growth, electoral cycle
On the security of the Quantum Key Distribution protocols
6 pages, 1 table.-- Communication presented at the 5th World Multiconference on Systemics, Cybernetics and Informatics and 7th International Conference on Information System Analysis and Synthesis (SCI/ISAS 2001, Orlando, Florida, Jul 22-25, 2001).The advent of quantum computers may compromise the security of today's conventional cryptosystems. Quantum key distribution protocols are proposed to
ward off such threat; but, for the moment, the proposed quantum protocols are an hybrid of classical and quantum mechanisms and, as a consequence, they will result compromised as easily as conventional cryptography by quantum cryptanalysis.This work was supported by CICYT, Spain, under grant TEL98-1020 and by MEC under Programa de estancias de CientĂficos y TecnĂłlogos Extranjeros en España.Peer reviewe
Cracking the laugh code: laughter through the lens of biology, psychology and neuroscience
Preface to the theme issue which tackles the biological, psychological, neural, and cultural underpinnings of laughter in humans and other animals from a naturalistic and evolutionary perspective
The naturalistic approach to laughter in humans and other animals: towards a unified theory
This opinion piece aims to tackle the biological, psychological, neural and
cultural underpinnings of laughter from a naturalistic and evolutionary
perspective. A naturalistic account of laughter requires the revaluation of
two dogmas of a longstanding philosophical tradition, that is, the quintessen tial link between laughter and humour, and the uniquely human nature of
this behaviour. In the spirit of Provineâs and Pankseppâs seminal studies,
who firstly argued against the anti-naturalistic dogmas, here we review com pelling evidence that (i) laughter is first and foremost a social behaviour
aimed at regulating social relationships, easing social tensions and establish ing social bonds, and that (ii) homologue and homoplasic behaviours of
laughter exist in primates and rodents, who also share with humans the
same underpinning neural circuitry. We make a case for the hypothesis
that the contagiousness of laughter and its pervasive social infectiousness
in everyday social interactions is mediated by a specific mirror mechanism.
Finally, we argue that a naturalistic account of laughter should not be
intended as an outright rejection of classic theories; rather, in the last part
of the piece we argue that our perspective is potentially able to integrate
previous viewpointsâincluding classic philosophical theoriesâultimately
providing a unified evolutionary explanation of laughter
Reduction of the Delays within an Intrusion Detection System (IDS) based on Software Defined Networking (SDN)
Software Defined Networking (SDN) is a very useful tool not only to manage networks but also to increase network security, in particular by implementing Intrusion Detection Systems (IDS) directly into the SDN architecture. The implementation of IDS within the SDN paradigm can simplify the implementation, speed up incident responses, and, in general, allow to promptly react to cyber attacks through proper countermeasures. Nevertheless, embedding IDS within SDN also introduces delays that cannot be tolerated in specific network environments, like industrial control systems. This paper focuses on the implementation of an IDS based on Machine Learning (ML) algorithms into an SDN architecture and proposes a very practical approach to reduce the delay by using the sequential implementation of prototypes of increasing software and hardware complexity so allowing quick tests to highlight the main problems, solve them and pass to the next operative step. A fully validated performance evaluation is then shown by exploiting all the presented solutions and by using further improved hardware features. The overall performance is very good and compliant with most, even if not yet all, industrial control systems constraints. Results show how the proposed solutions provide a significant improvement of the latency so opening the door to a real implementation in the field
Assembly of peptidoglycan fragments: a synthetic challenge
SFRH/BD/52207/2013
PTDC/BIA-MIC/30746/2017
UID/QUI/50006/2019
POCI-01-0145-FEDER-007265
UID/Multi/04378/2019Peptidoglycan (PGN) is a major constituent of most bacterial cell walls that is recognized as a primary target of the innate immune system. The availability of pure PGN molecules has become key to different biological studies. This review aims to (1) provide an overview of PGN biosynthesis, focusing on the main biosynthetic intermediates; (2) focus on the challenges for chemical synthesis posed by the unique and complex structure of PGN; and (3) cover the synthetic routes of PGN fragments developed to date. The key difficulties in the synthesis of PGN molecules mainly involve stereoselective glycosylation involving NAG derivatives. The complex synthesis of the carbohydrate backbone commonly involves multistep sequences of chemical reactions to install the lactyl moiety at the O-3 position of NAG derivatives and to control enantioselective glycosylation. Recent advances are presented and synthetic routes are described according to the main strategy used: (i) based on the availability of starting materials such as glucosamine derivatives; (ii) based on a particular orthogonal synthesis; and (iii) based on the use of other natural biopolymers as raw materials.publishersversionpublishe
Multifunctional peri-urban agriculture: Some ecosystem services of a sustainable olive grove
This study reports the influence of a sustainable management model which entails the recycling of urban wastewater and distribution by drip irrigation, recycling of polygenic carbon sources internal to the olive orchard (cover crops, pruning material) on yield, soil water holding capacity, soil biodiversity. Sustainable management practices were applied for a 15-year period in a 2-ha olive orchard located in an hilly peri-urban zone of southern Italy, where olive tree represents the dominant crop and has a key role inside the traditional landscape. A comparison between sustainable and conventional management (soil tillage, burning of the pruning residues, mineral fertilization, empirical irrigation) was carried out. This study suggests some guidelines of a sustainable management of peri-urban olive groves, with benefits to the whole agro-ecosystem stability and to the near town, recognizing the multifunctional role of agriculture that enhances the creation of synergies between urban and rural areas
On magnetic field generation in Kolmogorov turbulence
We analyze the initial, kinematic stage of magnetic field evolution in an
isotropic and homogeneous turbulent conducting fluid with a rough velocity
field, v(l) ~ l^alpha, alpha<1. We propose that in the limit of small magnetic
Prandtl number, i.e. when ohmic resistivity is much larger than viscosity, the
smaller the roughness exponent, alpha, the larger the magnetic Reynolds number
that is needed to excite magnetic fluctuations. This implies that numerical or
experimental investigations of magnetohydrodynamic turbulence with small
Prandtl numbers need to achieve extremely high resolution in order to describe
magnetic phenomena adequately.Comment: 4 pages, revised, new material adde
Efficacy Of Electroacupuncture For Myofascial Pain In The Upper Trapezius Muscle: A Case Series.
Electroacupunture (EA) includes the passage of an electrical current through the acupuncture needle and is commonly used for pain relief. To evaluate the EA treatment effects for myofascial pain in the upper trapezius muscle. Twenty women aged ranging from 18 to 40 years (mean=24.95; SD=5.88 years), with a body mass index ranging from 19 to 25 kg/m2 (mean=22.33; SD=0.56 kg/m2), with regular menstrual cycles controlled by oral contraceptive, local or referred pain for more than six months and at least one myofascial trigger point in the upper trapezius participated in this study. The participants received a total of nine EA sessions over five weeks. The needles were inserted at the accupoints GB20, GB21, LV3, LI4, and at ashi points. A mixed current of 2 Hz and 100 Hz was applied alternatively every 5 seconds for 30 minutes. The outcomes were pain intensity measured by the visual analogue scale (VAS), pressure pain threshold (PPT) measured by an algometer, electromyography (EMG) and quality of life measured by the SF-36 questionnaire. Inter-occurrences between sessions were monitored. Paired t-test, Wilcoxon test, and repeated measure analysis of variance (ANOVA) having Tukey-Kramer as post-hoc tests were used. Significant improvement in pain intensity and in PPT occurred after treatment (P<0.0001). EMG of the right trapezius during contraction increased significantly, suggesting muscle function enhancement; the quality of life improved, related to physical components of the SF-36 (P<0.05). The EA showed to be a reliable method for myofascial pain relief. Large randomized blinded controlled trials might be carried out to confirm these results. Article registered in the Registro Brasileiro de Ensaios ClĂnicos under number RBR-4hb6f6.15371-
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