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This paper uses recently developed robust estimation methods to empirically reassess the long-standing inflation-unemployment trade-off debate. Indeed, we study to what extent unemployment-based New Keynesian Phillips Curves are informative about the relationship between inflation dynamics and labour market conditions. In particular, we attempt to quantify the ‘elasticities’ of inflation with respect to unemployment of two economies, the US and the Euro Area, which are known to have markedly distinct labour market characteristics. We find that the relevance of the inflation-unemployment trade-off and its empirical adequacy is greatly enhanced once the informational content of key labour market variables is explored in our estimations.

The realization that evolutionary feedbacks need to be considered to fully grasp ecological dynamics has sparked interest in the effect of evolution on community properties like coexistence and productivity. However, little is known about the evolution of community robustness and productivity along diversification processes in species-rich systems. We leverage the recent structural approach to coexistence together with adaptive dynamics to study such properties and their relationships in a general trait-based model of competition on a niche axis. We show that the effects of coevolution on coexistence are two-fold and contrasting depending on the time scale considered. In the short term, evolution of niche differentiation strengthens coexistence, while long-term diversification leads to niche packing and decreased robustness. Moreover, we find that coevolved communities tend to be on average more robust and more productive than non-evolutionary assemblages. We illustrate how our theoretical predictions echo in observed empirical patterns and the implications of our results for empiricists and applied ecologists. We suggest that some of our results such as the improved robustness of Evolutionarily Stable Communities could be tested experimentally in suitable model systems. [ABSTRACT FROM AUTHOR]

How do financial frictions affect macroeconomic volatility and monetary policy in emerging market economies? This article assesses the empirical relevance of such frictions by estimating a two‐bloc emerging market/rest‐of‐the‐world model containing two key features of emerging economies: partial transaction and liability dollarization, and financial frictions where capital financing is partially or totally in foreign currency. Our estimation employs the "one‐step approach" which allows us to be "agnostic" regarding nonstationarity in the data and simultaneously estimate structural and trend parameters. Using data for Peru and the US, we find substantial empirical support for both the financial accelerator and partial dollarization mechanisms. The data fit of the baseline model improves with the addition of each of these frictions, exogenous shocks are significantly amplified in their presence and our preferred model captures several important stylized facts of a small emerging open economy. [ABSTRACT FROM AUTHOR]

The paper investigates whether the institutional arrangements that determine the conduct of monetary and prudential policies influence policymakers' actions in pursuing their designated mandates. Employing recently developed dynamic heterogeneous panel methods and using data for 25 industrialized countries from 1960 to 2018, we empirically assess whether central banks' main objective of inflation stability is compromised when assigned with both policy mandates manifested as inflation bias. Our results show that, once we appropriately control for relevant policy and institutional factors, the separation of macroprudential regulation and monetary policy does not have a significant effect on inflation outcomes. [ABSTRACT FROM AUTHOR]

This paper uses recently developed robust estimation methods to empirically reassess the long-standing inflation-unemployment trade-off debate. Indeed, we study to what extent unemployment-based New Keynesian Phillips Curves are informative about the relationship between inflation dynamics and labor market conditions. In particular, we attempt to quantify the 'elasticities' of inflation with respect to unemployment in two economies, the US and the Euro Area, whose labor market characteristics are admittedly very different. We find that the relevance of the inflation-unemployment trade-off and its empirical adequacy is greatly enhanced once the informational content of key labor market variables is explored in our estimations. [ABSTRACT FROM AUTHOR]

This paper intends to assess and test long-term memory in the Euronext stock indexes returns in the search for fractal dynamics that refute the random walk hypothesis. The Hurst exponents estimated through Rescaled-Range and Detrended Fluctuation Analysis evidence long memory in the form of persistence for all markets, with the exception of CAC 40 by the DFA. However, the Rescaled-Range Tests neither reject the absence of long dependency nor reject the existence of short dependency. On the contrary, the Fractional Differencing Test supports the presence of persistence in the PSI 20, ISE 20 and OBX indexes. This suggests that these markets are more prone to predictability, but also trends that may be unexpectedly disrupted by discontinuities, exhibiting dynamics incompatible with random walk behavior and providing evidence against the weak form of efficiency and validity of the asset pricing models. [ABSTRACT FROM AUTHOR]

We present evidence on the operation of incentive pay from a field experiment in Pakistan, looking at piece rates and pay based on rank achieved in a tournament. Importantly, some workers are in contracts 'tying' them to the employer for several picking seasons; others are 'untied', in the sense of being employed for only the current season. We find that incentive pay (of either type) improves productivity by 30%, on average, but that there are important differences across the types of workers: in particular, tournament incentives are less effective amongst the tied workers. We suggest that our main results have implications for tournament theory and the design of incentive pay schemes, particularly with regard to the fact that they may discourage some workers and, thus, reduce incentives. [ABSTRACT FROM AUTHOR]

Westudy the effects of disorder on the coupling strength of coupled photonic crystal slab cavities by considering fully-3D electromagnetic calculations. Specifically, we investigate two coupled L3 cavities at 30° and 60° configurations, where the coupling strength J (or photon hopping) is extracted from the simulations in the presence of disorder.Wefound that the relative fluctuations of the photon hopping are more sensitive to disorder effects than the corresponding fluctuations in the eigenfrequencies of the coupled cavities. Furthermore, for the typical range of disorder in state-of-the-art devices, the J fluctuations are found to increase linearly as a function of the disorder amplitude. This allows one to set upper bounds to the amplitude of fabrication imperfections, for which the coupling predicted by design can still be expected, on average, in a fabricated device. [ABSTRACT FROM AUTHOR]

We study the mutual interaction between two identical quantum dots coupled to the normal modes of two-site photonic crystal molecules in a planar waveguide geometry, i.e., photonic crystal dimers. We find that the radiative coupling between the two quantum emitters is maximized when they are in resonance with either the bonding or the antibonding modes of the coupled-cavity system. Moreover, we find that such effective interdot coupling is sizable, in the range of ∼1 meV, and almost independent from the cavities' distance, as long as a normal-mode splitting exceeding the radiative linewidth can be established (strong cavity-cavity coupling condition). In realistic and high-quality-factor photonic crystal cavity devices, such distance can largely exceed the emission wavelength, which is promising for long-distance entanglement generation between two qubits in an integrated nanophotonic platform. We show that these results are robust against position disorder of the two quantum emitters within their respective cavities. [ABSTRACT FROM AUTHOR]

The production of micromoulding blocks for the mass production of plastic microparts is associated to the decision of the more adequate micromanufacturing technology for the quickest time to moulding operation. The integration of subtractive and additive micro manufacturing technologies and micromoulding techniques made the development of plastics microcomponents in several domains of activity possible at feasible costs. However, the lifetime expectancy of their replication tools is directly dependent on the tool material properties and the thermal and mechanical characteristics of moulding process. Besides the tool manufacturing costs, post-treatments to achieve the enhancement of tool properties as surface roughness or abrasion resistance must also be considered, so that the mass production process results technically and economically effective. Thus, a trade-off is required to establish the break-even point between the overall tool cost and the tool lifetime. An analysis was made on the design of plastics microparts considering their performance requirements and implications on the tooling manufacturing route and expected production life. It was considered the use of additive and subtractive technologies for the microtooling manufacture using current industrial equipment. This study enabled a possible approach using the Analytical Hierarchical Process (AHP) towards the detailed analysis of the life cycle and production costs of common routes in microinjection moulding. A study of this type requires the continuous update of micromanufacturing technological developments in order to score actual process features. This analytical hierarchization approach enables decision makers to input market requirements and to obtain suitable manufacturing solutions, considering the continuous technological challenges and economical aspects. [ABSTRACT FROM AUTHOR]

We derive the conditions under which time-varying cointegration leads to cointegration spaces that may be time-invariant or, in contrast, time-varying. The model of interest is a vector error correction model with arbitrary time-varying cointegration parameters. We clarify the role of identification and normalization restrictions and show that structural breaks in error-correction models may actually correspond to stable long-run economic relationships, as opposed to a single-equation setup, in which an identification restriction is imposed. Moreover, we show that, in a time-varying cointegrating relationship with a given number of variables and cointegration rank, there is a minimum number of orthogonal Fourier functions that most likely guarantees time-varying cointegrating spaces. [ABSTRACT FROM AUTHOR]

We investigate the reflectivity spectra of photonic crystal cavities using the polarization of the incoming exciting light to tune the Fano interference between the radiation reflected by the polarized cavity mode and the light scattered by the photonic crystal pattern. The reflectivity is controlled by the polarization of the incident radiation, with the change from symmetrical to asymmetrical lineshapes well described by the Fano resonance formula. We use the scattering matrix formalism to obtain the reflectivity lineshapes by relating the electromagnetic field incident on the cavity to the radiation that is reflected in qualitative good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

The important contribution by Basu and Fernald (2002) shows that, in practice, there is a statistically significant gap between aggregate productivity and technology that can be attributed to inefficient product and labour markets. This is important, as it implies that the Solow residual is an imperfect index for aggregate technology change. We take a related approach and find that when we control for capacity utilization, time varying markup and account for externalities between industries, by employing a superior system estimator, the gap between the aggregate productivity and technology is shown to narrow considerably. [ABSTRACT FROM AUTHOR]

This paper argues that nonlinear adjustment may provide a better explanation of fluctuations in the consumption-wealth ratio. The nonlinearity is captured by a Markov-switching vector errorcorrection model that allows the dynamics of the relationship to differ across regimes. Estimation of the system suggests that these states are related to the behaviour of financial markets. In fact, estimation of the system suggests that short-term deviations in the consumption-wealth ratio will forecast either asset returns or consumption growth; the first when changes in wealth are transitory, the second when changes in wealth are permanent. Our approach uncovers a richer and more complex dynamic in the consumption-wealth ratio than previous results in the literature, whilst being in accordance with theoretical predictions of a simple model of consumption under uncertainty. [ABSTRACT FROM AUTHOR]

The aim of the study was to analyse the semiology of seizures in children with frontal lobe epilepsy (FLE) and to compare them with other paediatric cohorts described in the literature as well as with adult counterparts. We analysed 174 registered seizures of 18 cases under 12 years with lesional epilepsy whose frontal origin was defined by the concordance of neuroimaging and ictal electrographic findings, and confirmed by surgery in the six cases operated on. Seizures were generally short, with a high daily frequency and usually related to sleep. The most characteristic semiological pattern consisted of complex motor seizures, particularly hypermotor. Often seizures corresponded to a mixture of different semiological patterns (tonic, gelastic, automotor, hypermotor, versive) presenting in the same seizure, often as a unique type in the same patient. With regard to several aspects the semiology of FLE in our cohort looks like that reported in adult series, in particular as to the frequency of complex motor seizures. However, our cohort was also characterised by a more protean array of seizure semiology, stressing the occurrence of seizures typically present in adults (versive and complex motor) and of some seizure patterns more characteristic in children such as epileptic spasms; moreover, the rare occurrence of secondarily generalised tonic clonic seizures (SGTCS) was confirmed. [ABSTRACT FROM AUTHOR]

This study addresses some modelling questions related to the possibility of structural change in models with nonstationary variables. Focusing on cointegration issues, some methodological aspects are discussed, attempting to integrate coherently the several steps of the modelling strategy. These range from unit root to cointegration testing and to testing for instability in the cointegration vector. An empirical example with Portuguese data tries to illustrate the usefulness of this approach, where a simple money demand function is estimated using an error-correction model (ECM). If a break is explicitly allowed in the cointegration vector the forecasting performance of the ECM improves. [ABSTRACT FROM AUTHOR]

We present a fully three-dimensional Bloch mode expansion technique and a photon Green function formalism to compute the quality factors, mode volumes, and Purcell enhancement distributions of a disordered W1 photonic crystal slab waveguide in the slow-light Anderson-localization regime. By considering fabrication (intrinsic) and intentional (extrinsic) disorder we find that the Purcell enhancement statistics are well described by log-normal distributions without any fitting parameters. We also compare directly the effects of hole size fluctuations as well as fluctuations in the hole position. The functional dependence of the mean and standard deviation of the quality factor and Purcell enhancement distributions is found to decrease exponentially with the square root of the extrinsic disorder parameter. The strong coupling probability between a single quantum dot and an Anderson-localized mode is numerically computed and found to exponentially decrease with the squared extrinsic disorder parameter, where low disordered systems give rise to larger probabilities when state-of-the-art quantum dots are considered. The optimal spatial regions to position quantum dots in the W1 waveguide are also discussed. These theoretical results are fundamentally interesting for disordered photonics and connect to recent experimental works on photonic crystal slab waveguides in the slow-light regime. Our three-dimensional slab results also contradict some previous findings that use simpler two-dimensional models to understand these complex planar systems. [ABSTRACT FROM AUTHOR]

We show that two spatially separated semiconductor quantum dots under resonant and continuous-wave excitation can be strongly entangled in the steady state, thanks to their radiative coupling by mutual interaction through the normal modes of a photonic crystal dimer. We employ a quantum master equation formalism to quantify the steady-state entanglement by calculating the system negativity. Calculations are specified to consider realistic semiconductor nanostructure parameters for the photonic crystal dimer-quantum dots coupled system, determined by a guided-mode expansion solution of Maxwell equations. Negativity values of the order of 0.1 (20% of the maximum value) are shown for interdot distances that are larger than the resonant wavelength of the system. It is shown that the amount of entanglement is almost independent of the interdot distance, as long as the normal mode splitting of the photonic dimer is larger than their linewidths, which becomes the only requirement to achieve a local and individual qubit addressing. Considering inhomogeneously broadened quantum dots, we find that the steady-state entanglement is preserved as long as the detuning between the two quantum dot resonances is small when compared to their decay rates. The steady-state entanglement is shown to be robust against the effects of pure dephasing of the quantum dot transitions. We finally study the entanglement dynamics for a configuration in which one of the two quantum dots is initially excited and find that the transient negativity can be enhanced by more than a factor of two with respect to the steady-state value. These results are promising for practical applications of entangled states at short time scales. [ABSTRACT FROM AUTHOR]

The main objective of automatic environmental radiation warning networks is to quantify a set of radiological parameters corresponding to the medium being monitored (water, air, etc) in the shortest possible time so as to be able to provide rapid and precise information on the medium’s radiological status, and on any alterations that may occur and their severity. Specifically, in this paper we present the substantial improvements that have been carried out in an automatic near-real-time radiation monitoring of a water system belonging to Radiation Alert Network of Extremadura (RARE) in southwest Spain. These improvements are based on the incorporation of (i) a gamma spectrometry system with solid scintillation detectors and compact digital electronics, (ii) continuous measurement of the water flow that is being monitored, (iii) improvements in the maintenance tasks required to optimise the operation of this type of equipment and (iv) the controlled and automated collection of water samples so that, in the case of a possible radiological anomaly, it will be possible to perform ulterior specific complementary determinations in a low-background laboratory. [ABSTRACT FROM AUTHOR]

The article discusses research being done on the use of telepathology in northern Sweden. The researchers have developed telepathology services based on static and dynamic image transfer. Their goal was to offer wide spectrum of normal pathological, cytological and hematological services. Primary activities that were carried out in order to develop a telepathology service are mentioned.