Migrants at work: perspectives, perceptions and new connections. Work, Employment and Society, 34 (5) . pp. 745-748. ISSN 0950-0170

Migration – and the experiences of migrants – continue to occupy an important and controversial place in the scholarly and political debates on contemporary labour markets and societies. As new scenarios emerge at local, national and global levels, new insights and perspectives become necessary. The articles in this themed issue reflect the interest Work, Employment and Society has had in the topic of labour migrations and migrants at work for well over a decade and which led, for example, to the themed issue Migration at Work: Spaces, Borders and Boundaries in 32(5), 2018. Migration has of course been a prominent issue across the social sciences, and in recent years particularly in relation to the ‘refugee crisis’ of 2015 and to intra-European migration ahead of and in light of Brexit. The experiences of migrants from Eastern and Central Europe in the workplace, their overqualification and devaluing of their cultural capital, and their positioning within segmented labour markets have produced a number of articles in past issues (e.g. Ciupijus, 2011; Samaluk, 2016; Sirkeci et al., 2018) to which those in the current issue (Leschke and Weiss; Rydzik and Anitha) make an important addition. [...

Searching in Unstructured Overlays Using Local Knowledge and Gossip

This paper analyzes a class of dissemination algorithms for the discovery of distributed contents in Peer-to-Peer unstructured overlay networks. The algorithms are a mix of protocols employing local knowledge of peers' neighborhood and gossip. By tuning the gossip probability and the depth k of the k-neighborhood of which nodes have information, we obtain different dissemination protocols employed in literature over unstructured P2P overlays. The provided analysis and simulation results confirm that, when properly configured, these schemes represent a viable approach to build effective P2P resource discovery in large-scale, dynamic distributed systems.Comment: A revised version of the paper appears in Proc. of the 5th International Workshop on Complex Networks (CompleNet 2014) - Studies in Computational Intelligence Series, Springer-Verlag, Bologna (Italy), March 201

A COMPREHENSIVE ENERGETIC, EXERGETIC AND HEAT TRANSFER ANALYSIS OF A SOLAR ORGANIC RANKINE SYSTEM

Environmental concerns have been motivating the use of renewable energysources to meet sustainable requirements. In this context, concentrated solarpower driven by organic Rankine cycles has been classified as an up-andcomingtechnology to generate energy under low and moderate temperatures.In order to have a better understanding of the availability and utilization of thisenergy resource, the purpose of the present study is to perform acomprehensive energetic, exergetic and heat transfer analysis of a 200 kWsolar organic Rankine cycle through the presentation of the energy and exergyefficiencies and losses for each component; the exergy destruction at all stagesof the process; and the heat transfer behavior along the receiver. The thermalmodel was developed in Engineering Equation Solver and validated withliterature data. The solar collector was operated with Therminol 66 and theworking fluid employed in the power block was cyclohexane. The energeticefficiencies achieved in the solar field, power block, and overall system were64.97; 21.36; and 13.87 %, respectively. Considering the exergetic efficiencies,they were 27.37; 54.45; and 14.89 %, respectively. The solar resource variationshowed that the higher DNI value, the better the system performance

Identifying entanglement using quantum "ghost" interference and imaging

We report a quantum interference and imaging experiment which quantitatively demonstrates that Einstein-Podolsky-Rosen (EPR) type entangled two-photon states exhibit both momentum-momentum and position-position correlations, stronger than any classical correlation. The measurements show indeed that the uncertainties in the sum of momenta and in the difference of positions of the entangled two-photon satisfy both EPR inequalities D(k1+k2)<min(D(k1),D(k2)) and D(x1-x2)<min(D(x1),D(x2)). These two inequalities, together, represent a non-classicality condition. Our measurements provide a direct way to distinguish between quantum entanglement and classical correlation in continuous variables for two-photons/two photons systems.Comment: We have changed Eq.(2) from one inequality to two inequalities. The two expressions are actually consistent with each other, but the new one represents a more stringent condition for entanglement and, in our opinion, better explains the original idea of EPR. We have clarified this point in the paper. 4 pages; submitted to PR

A decidable policy language for history-based transaction monitoring

Online trading invariably involves dealings between strangers, so it is important for one party to be able to judge objectively the trustworthiness of the other. In such a setting, the decision to trust a user may sensibly be based on that user's past behaviour. We introduce a specification language based on linear temporal logic for expressing a policy for categorising the behaviour patterns of a user depending on its transaction history. We also present an algorithm for checking whether the transaction history obeys the stated policy. To be useful in a real setting, such a language should allow one to express realistic policies which may involve parameter quantification and quantitative or statistical patterns. We introduce several extensions of linear temporal logic to cater for such needs: a restricted form of universal and existential quantification; arbitrary computable functions and relations in the term language; and a "counting" quantifier for counting how many times a formula holds in the past. We then show that model checking a transaction history against a policy, which we call the history-based transaction monitoring problem, is PSPACE-complete in the size of the policy formula and the length of the history. The problem becomes decidable in polynomial time when the policies are fixed. We also consider the problem of transaction monitoring in the case where not all the parameters of actions are observable. We formulate two such "partial observability" monitoring problems, and show their decidability under certain restrictions

Unstable Planetary Systems Emerging Out Of Gas Disks

The discovery of over 400 extrasolar planets allows us to statistically test our understanding of formation and dynamics of planetary systems via numerical simulations. Traditional N-body simulations of multiple-planet systems without gas disks have successfully reproduced the eccentricity (e) distribution of the observed systems, by assuming that the planetary systems are relatively closely packed when the gas disk dissipates, so that they become dynamically unstable within the stellar lifetime. However, such studies cannot explain the small semi-major axes (a) of extrasolar planetary systems, if planets are formed, as the standard planet formation theory suggests, beyond the ice line. In this paper, we numerically study the evolution of three-planet systems in dissipating gas disks, and constrain the initial conditions that reproduce the observed semi-major axis and eccentricity distributions simultaneously. We adopt the initial conditions that are motivated by the standard planet formation theory, and self-consistently simulate the disk evolution, and planet migration by using a hybrid N-body and 1D gas disk code. We also take account of eccentricity damping, and investigate the effect of saturation of corotation resonances on the evolution of planetary systems. We find that the semi-major axis distribution is largely determined in a gas disk, while the eccentricity distribution is determined after the disk dissipation. We also find that there may be an optimum disk mass which leads to the observed a-e distribution. Our simulations generate a larger fraction of planetary systems trapped in mean-motion resonances (MMRs) than the observations, indicating that the disk's perturbation to the planetary orbits may be important to explain the observed rate of MMRs. We also find much lower occurrence of planets on retrograde orbits than the current observations of close-in planets suggest.Comment: 12 pages, 9 figures, accepted for publication in Ap

Application of the liposuction techniques and principles in specific body areas and pathologies

The buttocks have been a symbol of attraction, sexuality and eroticism since ancient times and therefore, they have an important role in defining the posterior body contour. More and more people are talking about and understand the meaning and the role that buttocks play in modeling and physical beauty. The three dimensional gluteoplasty (3-DGP) is an innovative technique that allows us to change volume, shape and firmness, not only in the buttocks but also in the adjacent regions such as the thighs and trochanters, becoming an ideal tool to answer the frequent reasons of consultation of our patients about this particular area of the body: ..

Surgical treatment of an aseptic fistulized acromioclavicular joint cyst: a case report and review of the literature

An acromioclavicular joint cyst is an uncommonly reported condition, which seems to result from a massive rotator cuff tear and degenerative osteoarthritis of the acromioclavicular joint. We present the case of an 81-year-old man affected by an acromioclavicular joint cyst, associated to a massive rotator cuff tear, proximal migration of the humeral head and osteoarthritis of the gleno-humeral joint. The mass was 7 × 2.5 cm in size and the overlying skin presented a fistula that drained clear synovial-like fluid. Plain X-ray examination of the left shoulder showed proximal migration of the humeral head migration and osteoarthritis of the gleno-humeral joint, and further MRI evaluation confirmed the clinical diagnosis of a complete rotator cuff tear and observed a large subcutaneous cyst in communication with the degenerative acromioclavicular joint. The patient underwent surgical excision of the cyst and lateral resection of the clavicle to prevent disease recurrence. To the best of our knowledge, this is the first reported case of an acromioclavicular joint cyst complicated by an aseptic fistula resulting from multiple aspirations

Enhancing image contrast using coherent states and photon number resolving detectors

We experimentally map the transverse profile of diffraction-limited beams using photon-number-resolving detectors. We observe strong compression of diffracted beam profiles for high detected photon number. This effect leads to higher contrast than a conventional irradiance profile between two Airy disk-beams separated by the Rayleigh criterion.Comment: 7 pages, 3 figures, accepted for publication in Optics Expres

Estudio paleoestomatológico de la población tardorromana de La Muela (Valencia de Don Juan, León)

X Congreso Nacional de Paleopatología. Univesidad Autónoma de Madrid, septiembre de 200