1,954 research outputs found
Social segregation of indigenous migrants in Mexico: An overview from Monterrey
In Mexico, rural to urban migration is a clearly noticeable phenomenon. During the last few years, there has been spontaneous growth in the migration of indigenous people towards the northern cities of Mexico, especially to Monterrey, in search of employment. Once the migrants arrive in this metropolis, they face difficulties adjusting and adapting to the city environment because of hidden discrimination. The main argument and hypothesis of this paper is that indigenous people isolate themselves and segregate themselves socially due to fear of (cultural and racial) discrimination and violence. For this study, data were obtained from fieldwork carried out during 2009 and 2010 in Monterrey, Mexico, where we interviewed 350 indigenous people that had moved there from different parts of the country
Synergy Between Quantum Circuits and Tensor Networks: Short-cutting the Race to Practical Quantum Advantage
While recent breakthroughs have proven the ability of noisy
intermediate-scale quantum (NISQ) devices to achieve quantum advantage in
classically-intractable sampling tasks, the use of these devices for solving
more practically relevant computational problems remains a challenge. Proposals
for attaining practical quantum advantage typically involve parametrized
quantum circuits (PQCs), whose parameters can be optimized to find solutions to
diverse problems throughout quantum simulation and machine learning. However,
training PQCs for real-world problems remains a significant practical
challenge, largely due to the phenomenon of barren plateaus in the optimization
landscapes of randomly-initialized quantum circuits. In this work, we introduce
a scalable procedure for harnessing classical computing resources to provide
pre-optimized initializations for PQCs, which we show significantly improves
the trainability and performance of PQCs on a variety of problems. Given a
specific optimization task, this method first utilizes tensor network (TN)
simulations to identify a promising quantum state, which is then converted into
gate parameters of a PQC by means of a high-performance decomposition
procedure. We show that this learned initialization avoids barren plateaus, and
effectively translates increases in classical resources to enhanced performance
and speed in training quantum circuits. By demonstrating a means of boosting
limited quantum resources using classical computers, our approach illustrates
the promise of this synergy between quantum and quantum-inspired models in
quantum computing, and opens up new avenues to harness the power of modern
quantum hardware for realizing practical quantum advantage.Comment: 15 pages, 7 figure
Exploring Ancient Pashupati: Preliminary Results of Archaeological Surveys and Excavations at Bhandarkhal, Kathmandu Valley UNESCO World Heritage Property (Nepal)
Re-investigating Tilaurakot's Ancient Fortifications: a preliminary report of excavations through the northern rampart at Tilaurakot(Nepal)
First paragraph: Urban settlements defined by fortification complexes have long been identified as one of the key indicators of the emergence and spread of the Early Historic Tradition across South Asia (Coningham 1995). Whilst performing defensive functions, city walls and moats are also thought to have prevented disruption to a settlement from natural forces, such as erosion and flooding (Narain and Roy 1977: 7, Coningham 1999: 54), as well as protecting settlements and crops grown within a city's boundary from wild animals (Coningham 1999: 56). Furthermore, some have argued that ramparts and moats also fulfilled symbolic functions and a number of settlement layouts have been thought to exhibit cosmomagical symbolism (Wheatley 1971: 481), with urban forms constructed as microcosms of the universe. Indeed, there are a number of South Asian examples where urban rampart and moat complexes are believed to have formed key cosmological motifs, representing the ocean and mountain range surrounding the universe (Coningham 2000). With a central role thus implied for the royal palace as representing Mount Meru, the dwelling of the Gods at the centre of the universe, this also portrayed the temporal ruler as a universal ruler or chakravartin (Wheatley 1971: 437, Coningham 2000: 350). Early Historic texts, such as the Arthasastra and Manasara, provided clear instructions for the construction of moats and ramparts, with the Arthasastra stating that a city should be quadrangular, surrounded by three moats and a rampart {Arthasastra 2.3.4-6) and be internally demarcated by cardinally orientated roads and gateways {Arthasastra 2.4.1-2). Similarly, the Manasara suggested that cities should be furnished with a quadrangular wall with an accompanying ditch surrounding the settlement with a gate at each cardinal direction {Manasara 9.107-109). It is now clear from its urban plan, that Tilaurakot, in southern Nepal, seemingly aligns with these precepts as it possesses an almost quadrangular fortification (Figure 1) and the results of recent geophysical survey suggest that cardinally-orientated roads were laid out in a grid within the city (Coningham et al. 2015)
Stress detection using wearable physiological and sociometric sensors
Stress remains a significant social problem for individuals in modern societies. This paper presents a machine learning approach for the automatic detection of stress of people in a social situation by combining two sensor systems that capture physiological and social responses. We compare the performance using different classifiers including support vector machine, AdaBoost, and k-nearest neighbour. Our experimental results show that by combining the measurements from both sensor systems, we could accurately discriminate between stressful and neutral situations during a controlled Trier social stress test (TSST). Moreover, this paper assesses the discriminative ability of each sensor modality individually and considers their suitability for real time stress detection. Finally, we present an study of the most discriminative features for stress detection
Reinventing ‘Many Voices’: MacBride and a Digital New World Information and Communication Order
The MacBride Commission Report was arguably one of the most significant multilateral interventions in the history of international communication. This article charts its emergence at the time of deeply contested Cold War politics, coinciding with the rise of the southern voices in the global arena, led by the non-aligned nations. Thirty-five years after the report's publication, has the global media evolved into a more democratic system, demonstrating greater diversity of views and viewpoints? Despite the still formidable power of US-led western media, the article suggests that the globalisation and digitisation of communication has contributed to a multi-layered and more complex global media scene, demonstrating the “rise of the rest”
Cognitive Performance and Heart Rate Variability: The Influence of Fitness Level
In the present study, we investigated the relation between cognitive performance and heart rate variability as a function of fitness level. We measured the effect of three cognitive tasks (the psychomotor vigilance task, a temporal orienting task, and a duration discrimination task) on the heart rate variability of two groups of participants: a high-fit group and a low-fit group. Two major novel findings emerged from this study. First, the lowest values of heart rate variability were found during performance of the duration discrimination task, compared to the other two tasks. Second, the results showed a decrement in heart rate variability as a function of the time on task, although only in the low-fit group. Moreover, the high-fit group showed overall faster reaction times than the low-fit group in the psychomotor vigilance task, while there were not significant differences in performance between the two groups of participants in the other two cognitive tasks. In sum, our results highlighted the influence of cognitive processing on heart rate variability. Importantly, both behavioral and physiological results suggested that the main benefit obtained as a result of fitness level appeared to be associated with processes involving sustained attention.This research was supported by the Spanish Ministerio de Educación y Cultura with a predoctoral grant (FPU-AP2010-3630) to the first author, Spanish grants SEJ2007-63645 from the Junta de Andalucía to Daniel Sanabria, Mikel Zabala and Esther Morales, and the CSD2008-00048 CONSOLIDER INGENIO (Dirección General de Investigación) to Daniel Sanabria
Melanopsin-expressing amphioxus photoreceptors transduce light via a phospholipase C signaling cascade
© The Author(s), 2012. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in PLoS One 7 (2012): e29813, doi:10.1371/journal.pone.0029813.Melanopsin, the receptor molecule that underlies light sensitivity in mammalian ‘circadian’ receptors, is homologous to invertebrate rhodopsins and has been proposed to operate via a similar signaling pathway. Its downstream effectors, however, remain elusive. Melanopsin also expresses in two distinct light-sensitive cell types in the neural tube of amphioxus. This organism is the most basal extant chordate and can help outline the evolutionary history of different photoreceptor lineages and their transduction mechanisms; moreover, isolated amphioxus photoreceptors offer unique advantages, because they are unambiguously identifiable and amenable to single-cell physiological assays. In the present study whole-cell patch clamp recording, pharmacological manipulations, and immunodetection were utilized to investigate light transduction in amphioxus photoreceptors. A Gq was identified and selectively localized to the photosensitive microvillar membrane, while the pivotal role of phospholipase C was established pharmacologically. The photocurrent was profoundly depressed by IP3 receptor antagonists, highlighting the importance of IP3 receptors in light signaling. By contrast, surrogates of diacylglycerol (DAG), as well as poly-unsaturated fatty acids failed to activate a membrane conductance or to alter the light response. The results strengthen the notion that calcium released from the ER via IP3-sensitive channels may fulfill a key role in conveying - directly or indirectly - the melanopsin-initiated light signal to the photoconductance; moreover, they challenge the dogma that microvillar photoreceptors and phoshoinositide-based light transduction are a prerogative of invertebrate eyes.This work was supported by the National Science Foundation of the USA (grant 0918930)
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Inward and Outward FDI Country Profiles, Second Edition
This second edition contains a series of 77 standardized country profiles dealing with the inward and outward foreign direct investment (FDI) performance of 40 economies. The profiles have been peer-reviewed by a global network of experts. The publication is intended to contribute to the analysis of trends in foreign direct investment and policy issues related to them. More specifically, the individual profiles discuss FDI trends and developments (country-level developments, the corporate players); effects of the recent global crises; and the policy scene. Each profile contains a standard set of tables, including on FDI stocks and flows, sectoral and geographical FDI distributions, the largest M&As and greenfield investments, the principal foreign affiliates (for inward FDI), and the principal multinational enterprises (for outward FDI). The standardized template used to produce the profiles allows cross-country comparisons. The volume is meant to be a reference tool for anyone interested in foreign direct investment
Rational Expectations Models with Higher Order Beliefs,” mimeo
Abstract This paper develops a general method of solving rational expectations models with higher order beliefs. Higher order beliefs are crucial in an environment with dispersed information and strategic complementarity, and the equilibrium policy depends on infinite higher order beliefs. It is generally believed that solving this type of equilibrium policy requires an infinite number of state variable
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