Miracle-dz/UniFAR-FTUs huggingface dataset:
Promoting Education Quality: the Role of Teachers' Unions in Latin America

Teachers unions play a major role in education policymaking in Latin America. In this paper, we review the literature and document cases where unions have likely had a positive impact on education. This has been primarily through their effect on the professionalization of the teaching force and their policy advocacy. Through publications, courses, and leadership opportunities, unions likely have positively contributed to instruction and teachers’ sense of purpose. Through policy advocacy, unions have informed governments of crucial local knowledge, have contributed research, and have established mechanisms of collaboration. We make the following policy recommendations: 1) Encourage unions’ professionalizing activities for teachers; 2) Establish institutionalized spaces where teachers can participate in the making of education policy, regardless of the government in power; and 3) Plan education policy democratically, incorporating unions. Introduction Public sector teachers’ unions are major actors in education politics in Latin America. Yet there has been little comparative study of their impact on education the region. There have been case studies, but existing knowledge is uneven, even among the cases that are the most well known (Argentina, Brazil, Chile, and Mexico). Moreover, researchers have tended to focus on the history of teachers’ unions, describing union mobilization and political interactions, rather than educational impact. This scholarly neglect may partially result from methodological challenges. For example, there has been conflict over how to identify, quantify, and analyze indicators related to education quality and teacher professionalism. What’s more, important background characteristics, like labor history and the evolution of education policy, vary greatly across Latin America, rendering questionable whether common patterns of teachers’ union behavior exist and whether cross-country comparisons can be generalized. Yet, the potential influence of teachers’ unions in Latin America has grown since 1990. Primary enrollment throughout the region has reached near universality in 1 Professor at the Universidade Federal Fluminense (Brazil). 2 Ph.D. Candidate in the Department of Government in Harvard University (USA). 3 Among others, see Núñez (1986) on Chile, Cook (1996) and Muñoz (2005) on Mexico, Ferreira Jr. (1998) on Brazil and Nardacchione (2009) on Argentina. See also Gindin and Melo (2011). 4 See UNESCO (2004) – especially chapter 1and Feldfeber (2007).
Binary-corrected velocity dispersions from single- and multi-epoch radial velocities: massive stars in R136 as a test case

Orbital motions from binary stars can broaden the observed line-of-sight velocity distribution of a stellar system, artificially inflating the measured line-of-sight velocity dispersion, which can in turn lead to erroneous conclusions about the dynamical state of the system. Cottaar et al. (2012b) proposed a maximum likelihood procedure to recover the intrinsic velocity dispersion of a resolved star cluster from a single epoch of radial velocity data of individual stars, which they achieved by simultaneously fitting the intrinsic velocity distribution of the single stars and the centres of mass of the binaries along with the velocity shifts caused by binary orbital motions. Assuming well-characterized binary properties, they showed that this procedure can accurately reproduce intrinsic velocity dispersions below 1 km s 1 for solar-type stars. Here we investigate the systematic o sets induced in cases where the binary properties are uncertain, and we show how two epochs of radial velocity data with an appropriate baseline can help to mitigate these systematic e ects. We first test the method above using Monte Carlo simulations, taking into account the large uncertainties in the binary properties of OB stars. We then apply it to radial velocity data in the young massive cluster R136, an example for which the intrinsic velocity dispersion of O-type stars is known from an intensive multi-epoch approach. For typical velocity dispersions of young massive clusters (& 4 km s 1 ) and with a single epoch of data, we demonstrate that the method can just about distinguish between a cluster in virial equilibrium and an unbound cluster. This is due to the higher spectroscopic binary fraction and more loosely constrained distributions of orbital parameters of OB stars compared to solar-type stars. By extending the maximum likelihood method to multiepoch data, we show that the accuracy on the fitted velocity dispersion can be improved to a few percent by using only two epochs of radial velocities. This procedure o ers a promising method of accurately measuring the intrinsic stellar velocity dispersion in other systems for which the binary properties are not well constrained, for example young clusters and associations whose luminosity is dominated by OB stars.
ST ] 4 M ay 2 01 8 GLOBAL TESTING UNDER SPARSE ALTERNATIVES FOR SINGLE INDEX MODELS By

By Qian Lin‡∗,† Zhigen Zhao§∗,† and Jun S. Liu¶∗ Tsinghua University‡ Temple University§ Harvard University¶ For the single index model y = f(βx, ǫ) with Gaussian design, where f is unknown and β is a sparse p-dimensional unit vector with at most s nonzero entries, we are interested in testing the null hypothesis that β, when viewed as a whole vector, is zero against the alternative that some entries of β is nonzero. Assuming that var(E[x | y]) is non-vanishing, we define the generalized signal-tonoise ratio (gSNR) λ of the model as the unique non-zero eigenvalue of var(E[x | y]). We show that if s log(p)∧p is of a smaller order of n, denoted as s log(p) ∧ p ≺ n, where n is the sample size, one can detect the existence of signals if and only if gSNR≻ p 1/2 n ∧ s log(p) n . Furthermore, if the noise is additive (i.e., y = f(βx) + ǫ), one can detect the existence of the signal if and only if gSNR≻ p 1/2 n ∧ s log(p) n ∧ 1 √ n . It is rather surprising that the detection boundary for the single index model with additive noise matches that for linear regression models. These results pave the road for thorough theoretical analysis of single/multiple index models in high dimensions.
The X-ray/SZ view of the virial region. II. Gas mass fraction

Several recent studies used the hot gas fraction of galaxy clusters as a standard ruler to constrain dark energy, which provides competitive results compared to other techniques. This method, however, relies on the assumption that the baryon fraction in clusters agrees with the cosmic value Omega_b/Omega_m, and does not differ from one system to another. We test this hypothesis by measuring the gas mass fraction over the entire cluster volume in a sample of local clusters. Combining the SZ thermal pressure from Planck and the X-ray gas density from ROSAT, we measured for the first time the average gas fraction (fgas) out to the virial radius and beyond in a large sample of clusters. We also obtained azimuthally-averaged measurements of the gas fraction for 18 individual systems, which we used to compute the scatter of fgas around the mean value at different radii and its dependence on the cluster's temperature. The gas mass fraction increases with radius and reaches the cosmic baryon fraction close to R200. At R200, we measure fgas,200=0.176+/-0.009. We find significant differences between the baryon fraction of relaxed, cool-core (CC) systems and unrelaxed, non-cool core (NCC) clusters in the outer regions. In average, the gas fraction in NCC clusters slightly exceeds the cosmic baryon fraction, while in CC systems the gas fraction converges to the expected value when accounting for the stellar content, without any evidence for variations from one system to another. We find that fgas estimates in NCC systems slightly disagree with the cosmic value approaching R200. This result could be explained either by a violation of the assumption of hydrostatic equilibrium or by an inhomogeneous distribution of the gas mass. Conversely, cool-core clusters are found to provide reliable constraints on fgas at overdensities >200, which makes them suitable for cosmological studies.
A Survey on Service Migration in Mobile Edge Computing

Mobile edge computing (MEC) provides a promising approach to significantly reduce network operational cost and improve quality of service (QoS) of mobile users by pushing computation resources to the network edges, and enables a scalable Internet of Things (IoT) architecture for time-sensitive applications (e-healthcare, real-time monitoring, and so on.). However, the mobility of mobile users and the limited coverage of edge servers can result in significant network performance degradation, dramatic drop in QoS, and even interruption of ongoing edge services; therefore, it is difficult to ensure service continuity. Service migration has great potential to address the issues, which decides when or where these services are migrated following user mobility and the changes of demand. In this paper, two conceptions similar to service migration, i.e., live migration for data centers and handover in cellular networks, are first discussed. Next, the cutting-edge research efforts on service migration in MEC are reviewed, and a devisal of taxonomy based on various research directions for efficient service migration is presented. Subsequently, a summary of three technologies for hosting services on edge servers, i.e., virtual machine, container, and agent, is provided. At last, open research challenges in service migration are identified and discussed.
Recent Advances in X-Ray Structures of Metal-Phenoxyl Radical Complexes

An “experimental” valence state of metal complexes is sometime different from the “formal” oxidation state, especially in the species having redox active ligands. This difference can be seen in biological system, such as iron(IV)-porphyrin π-cation radical in some heme proteins and copper(II)-phenoxyl radical in galactose oxidase (GO). Although structural characterizations of these species by X-ray diffraction methods have been rare due to their stability, some artificial metal-phenoxyl radical complexes have been synthesized and successfully characterized by X-ray crystal structure. In this review, syntheses and X-ray crystal structures of the one-electron oxidized metal-phenolate complexes, metal- phenoxyl radical, and high-valent metal phenolate species are discussed.
Profiling the immunome of little brown myotis provides a yardstick for measuring the genetic response to white‐nose syndrome

White‐nose syndrome (WNS) has devastated populations of hibernating bats in eastern North America, leading to emergency conservation listings for several species including the previously ubiquitous little brown myotis (Myotis lucifugus). However, some bat populations near the epicenter of the WNS panzootic appear to be stabilizing after initial precipitous declines, which could reflect a selective immunogenetic sweep. To investigate the hypothesis that WNS exerts significant selection on the immunome of affected bat populations, we developed a novel, high‐throughput sequence capture assay targeting 138 adaptive, intrinsic, and innate immunity genes of putative adaptive significance, as well as their respective regulatory regions (~370 kbp of genomic sequence/individual). We used the assay to explore baseline immunogenetic variation in M. lucifugus and to investigate whether particular immune genes/variants are associated with WNS susceptibility. We also used our assay to detect 1,038 putatively neutral single nucleotide polymorphisms and characterize contemporary population structure, providing context for the identification of local immunogenetic adaptation. Sequence capture provided a cost‐effective, “all‐in‐one” assay to test for neutral genetic and immunogenetic structure and revealed fine‐scale, baseline immunogenetic differentiation between sampling sites <600 km apart. We identified functional immunogenetic variants in M. lucifugus associated with WNS susceptibility. This study lays the foundations for future investigations of rangewide immunogenetic adaptation to WNS in M. lucifugus and provides a blueprint for studies of evolutionary rescue in other host–pathogen systems.
Child-reported depression and anxiety in preadolescence: II. Preschool predictors.

OBJECTIVE To examine the predictive association of parent- and teacher-reported behaviors at age 2 to 3 years in relation to child-reported depression and anxiety at age 10 to 11 years. METHOD Subjects were participants in a longitudinal study of 420 children aged 2 to 3 years from the general population first assessed in 1989 and again in 1991 (n = 397) and 1997 (n = 358). For the present study, 249 children were included for whom all relevant measures were obtained. These measures include the Child Behavior Checklist (CBCL) for 2- to 3-year-olds at time 1, the CBCL for 4- to 18-year-olds and the Teacher's Report Form at time 2, and the Dimensions of Depression Profile for Children and the State-Trait Anxiety Inventory for Children at time 3. RESULTS Only 5 and 8 of 220 parent-reported preschool problem items were significantly related to later child-reported depression and anxiety, respectively, and only 3 of 120 teacher-reported problem items were related to later anxiety. Of 120 teacher-reported preschool problem items, 21 were significantly related to later depression, including items referring to early signs of depression and social and academic problems. CONCLUSIONS Teachers, but not parents, can provide valuable information regarding preschool signals of preadolescent depression, but not anxiety. These signals include early social and academic problems.
Surface Modification of Titanium Plate with Anodic Oxidation and Its Application in Bone Growth

Using implants for dental applications are well-accepted procedures as one of the solutions for periodontal defect repair. Suitable design and materials, their reaction with the surrounding hard tissues and interfacial biomechanical properties are still considered to be the primary criteria which need to be addressed. The purpose of present study was to evaluate the bone repair around pure titanium implants and porous surface using anodic oxidation technique, after their insertion in tibiae of rats (n = 15). Five animals received pure titanium-surface implants in tibia, 5 rough-surface implants (TiO2/Ti) in tibia and last five acted as control group. The interfacial integrity and compositional variation along the interface were studied using scanning electron microscope (SEM) with energy dispersive analysis of X-ray (EDX) and histopathology after 2 months. The rats were sacrificed 8 weeks after surgery and fragments of the tibiae containing the implants were submitted to histological analyses to evaluate new bone formation at the implant-bone interface as well as the tibiae were radio graphed. The SEM-EDX results confirmed the initial stability for the Ti implant, but the regeneration of new bone formation was faster in the case of TiO2/Ti implant, and hence could be used for faster healing. The results of the histological analysis showed that osseointegration occurred for both types of implants with similar quality of bone tissue. In conclusion, the porous-surface implants contributed to the osseointegration because they provide a larger contact area with surface roughness at implant-bone interface can help into the formation of physico-chemical bondage with the surrounding hard tissues.
Inflation Dynamics in LATAM: A Comparison with Global Trends and Implications for Monetary Policy

This narrative, however, fits better the situation in the advanced world than in many emerging-market economies (EMEs). In this presentation I will put special emphasis in the recent inflationary experience of Latin America (LATAM), having in mind that there is heterogeneity in the region, hence it would be impossible to represent with this analysis every single country in the region. Contrary to what seems to be the norm among advanced economies (AEs), LATAM has seen a surge in inflation in the last 2 years. As I will argue, such trend prevails despite a slowdown in activity, and results mainly from a combination of external shocks and structural elements that make inflation dynamics in these countries especially susceptible to those shocks.
Design Considerations and Validation of Permanent Magnet Vernier Machine with Consequent Pole Rotor for Low Speed Servo Applications

This paper deals with design consideration and validation of a new pole-slot combination for permanent magnet vernier machine (PMVM) with consequent pole (CP) rotor especially for extremely low speed servo applications. A 136pole-24slot PMVM with CP rotor is introduced and analyzed by 2D and 3D finite element analysis (FEA) and discussion on experimental validation is also included.
Torque Ripple Minimization in Reaction Wheels Used in Satellites-A Comparison between Field Oriented Control of BLDCM and PMSM Using

AC motors have always been an area of interest in the field of electrical drives. With improvements in technology there is always a need of effective utilization of electrical power as well as the available resources. Nowadays the focus is given mainly on the efficiency of these drives with improvement in the performance of the motors used in the drives. Permanent magnet motors are classified as BLDC and PMSM among which Brushless DC Motor is one of the highly preferred AC motors used in various applications due to various advantages offered such as high efficiency, better speed versus torque characteristics. Although BLDC drives has several advantages it generates torque ripples which is a major concern in high precision applications especially in spacecrafts. Even though the torque generated is less when compared to BLDC motors, PMSM generates less torque ripples. Field oriented control of PMSM drives are becoming more popular especially in high precision applications. The main objective of this thesis is to make a comparison study between the FOC control of BLDC motor and PMSM using SVPWM technique in reducing torque ripples in reaction wheels used in satellites. FOC controlled AC motor drives provide better dynamic response and lesser torque ripples. The field oriented control scheme of the BLDC Motor drive and PMSM drive using SVPWM are simulated in MATLAB SIMULINK.
microRNA expression in tumour tissue and plasma in patients with newly diagnosed metastatic prostate cancer

Prostate cancer is the most common cancer among men in the western world. Clinical practice is continuously challenged by the pitfalls of the available diagnostic tools. microRNAs may represent promising biomarkers in many types of human cancers, including prostate cancer. The aim of this study was to investigate microRNA expression in tumour tissue and matched plasma in a cohort of patients with primary metastatic prostate cancer. The relative expression of 12 microRNAs was assessed in diagnostic needle biopsies from the prostate and matched plasma samples in two prospective cohorts (screening cohorts) comprising 21 patients with metastatic prostate cancer and 25 control patients. An independent validation cohort of plasma samples was collected prospectively from 149 newly diagnosed patients with local/locally advanced prostate cancer. Analyses were performed using real-time polymerase chain reaction. miRNA-93 showed a significant negative correlation between expression in tumour tissue and plasma in patients with metastatic prostate cancer. Furthermore, the plasma level of miRNA-93 significantly decreased after treatment in patients with local/locally advanced prostate cancer compared to baseline plasma level. The expression of six microRNAs (let-7b, miRNA-34a, -125b, -143, -145 and -221) was downregulated, and three microRNAs (miRNA-21, -25 and miRNA-93) were upregulated in tumour tissue compared to benign prostate tissue. In plasma, six microRNAs were upregulated (miRNA-21, -125b, -126, -141, -143 and -375), while let-7b was downregulated in patients with metastatic prostate cancer compared to the control cohort. In the metastatic prostate cancer cohort, the expression of four microRNAs (miRNA-125b, -126, -143 and -221), and miRNA-141 in tissue was associated with Gleason score and prostate-specific antigen, respectively. The expression of miRNA-93 in tumour tissue was correlated with matched plasma levels and showed a significant decrease in plasma level after intervention in local prostate cancer. Differential expression between tumour and benign prostate was detected for several microRNAs in both tissue and plasma.
Loss of sirtuin 1 and mitofusin 2 contributes to enhanced ischemia/reperfusion injury in aged livers

Ischemia/reperfusion (I/R) injury is a causative factor contributing to morbidity and mortality during liver resection and transplantation. Livers from elderly patients have a poorer recovery from these surgeries, indicating reduced reparative capacity with aging. Mechanisms underlying this age‐mediated hypersensitivity to I/R injury remain poorly understood. Here, we investigated how sirtuin 1 (SIRT1) and mitofusin 2 (MFN2) are affected by I/R in aged livers. Young (3 months) and old (23–26 months) male C57/BL6 mice were subjected to hepatic I/R in vivo. Primary hepatocytes isolated from each age group were also exposed to simulated in vitro I/R. Biochemical, genetic, and imaging analyses were performed to assess cell death, autophagy flux, mitophagy, and mitochondrial function. Compared to young mice, old livers showed accelerated liver injury following mild I/R. Reperfusion of old hepatocytes also showed necrosis, accompanied with defective autophagy, onset of the mitochondrial permeability transition, and mitochondrial dysfunction. Biochemical analysis indicated a near‐complete loss of both SIRT1 and MFN2 after I/R in old hepatocytes, which did not occur in young cells. Overexpression of either SIRT1 or MFN2 alone in old hepatocytes failed to mitigate I/R injury, while co‐overexpression of both proteins promoted autophagy and prevented mitochondrial dysfunction and cell death after reperfusion. Genetic approaches with deletion and point mutants revealed that SIRT1 deacetylated K655 and K662 residues in the C‐terminus of MFN2, leading to autophagy activation. The SIRT1‐MFN2 axis is pivotal during I/R recovery and may be a novel therapeutic target to reduce I/R injury in aged livers.
Imagined Affordances of Instagram and the Fantastical Authenticity of Female Gulf-Arab Social Media Influencers

This study explores the image sharing site Instagram to reveal how affordances, or uses of the platform, occur within a nexus of technological architecture, sociocultural contexts, and globalized commercial practices. It suggests social actors draw upon Instagram’s affordances at material, conceptual, and imaginary levels while using social media. This triadic model for theorizing affordances of Instagram responds to the need for mapping ontologies and typologies of social media within increasingly visual, intercultural, and non-Western contexts. The lenses of critical multimodality and a participant-centered method consider how female Gulf-Arab social media influencers operate through an interplay of shifting affordances in ways that challenge current conceptions of authenticity surrounding social media influencers. It is suggested that the triadic affordances of Instagram, occurring at material, conceptual, and imaginary levels, provide both influencers and followers with strategies of “fantastical authenticity” for navigating conflicting modes of representation and self-presentation within local and globalized economies.