Miracle-dz/UniFAR-FTUs huggingface dataset:
Social Security, Induced Retirement, and Aggregate Capital Accumulation:A Correction and Updating

In a 1974 paper in the Journal of Political Economy I discussed the theoretical ambiguity of the effect of social security on private saving and presented statistical evidence that social security does on balance depress saving. Recently, an error was detected in the computer program that was used to construct the "social security wealth" variable. I have now corrected that error and re estimated the original consumer expenditure equation. I have also updated the analysis by including the five years of additional data that have become available since the original study was completed. The new estimates, presented in the current note, continue to indicate that social security substantially depresses private saving. The point estimates of this effect are somewhat lower than before but nevertheless simply that social security depresses saving by about fifty percent of its current value. The estimated reduction in saving is more than two-thirds of the concurrent "contributions" of employees and employers to the social security retirement and survivors fund.
Forecasting Latin-American yield curves: An artificial neural network approach

This document explores the predictive power of the yield curves in Latin America (Colombia, Mexico, Peru and Chile) taking into account the factors set by the specifications of Nelson & Siegel and Svensson. Several forecasting methodologies are contrasted: an autoregressive model, a vector autoregressive model, artificial neural networks on each individual factor, and artificial neural networks on all factors that explain the yield curve. The out-of-sample performance of the fitting models improves with the neural networks in the one-month-ahead forecast along all studied yield curves. Moreover, the three factor model developed by Nelson & Siegel proves to be the best choice for out-of-sample forecasting. Finally, the success of the cross variable interaction strongly depends on the selected yield curve.
Exercise, but not quercetin, ameliorates inflammation, mitochondrial biogenesis, and lipid metabolism in skeletal muscle after strenuous exercise by high-fat diet mice

[Purpose] The purpose of this study was to investigate whether moderate exercise and quercetin intake with a low fat diet contribute to inflammatory cytokine production, mitochondrial biogenesis, and lipid metabolism in skeletal muscle after strenuous exercise by high-fat diet mice. [Methods] Male C57BL/6 mice were randomly divided into four groups: (1) High-fat for 12 weeks and low-fat diet control (C; n = 6); (2) high-fat diet for 12 weeks and low-fat diet with quercetin (Q; n = 4); (3) high-fat diet for 12 weeks and low-fat diet with exercise (E; n = 4); or (4) high-fat diet for 12 weeks and low-fat diet with exercise and quercetin (EQ; n = 5). Quercetin (10 mg/kg) was administered once per day, 5 day/week for 8 weeks. Exercise training was performed at moderate intensity for 8 weeks, 5 days/week for 30–60 min/day. Mice were subjected to a strenuous exercise bout of 60 min at a speed of 25 m/min (VO2 max 85%) conducted as an exercise-induced fatigue just before sacrifice. [Results] As results, body weights were significantly different among the groups. Exercise training significantly reduced inflammatory cytokines after strenuous exercise in skeletal muscle of high-fat diet mice. Exercise training increased Tfam mRNA in the soleus muscle after strenuous exercise. Exercise training significantly decreased lipogenesis markers in skeletal muscle of obese mice after strenuous exercise. Moderate exercise significantly increased lipolysis markers in the tibialis anterior muscle. [Conclusion] These findings suggest that exercise training reduced inflammatory cytokine levels and improved mitochondrial biogenesis and lipid metabolism. However quercetin supplementation did not affect these parameters. Thus, long-term moderate exercise training has positive effects on obesity.
Repeated observation of breast tumor subtypes in independent gene expression data sets

Characteristic patterns of gene expression measured by DNA microarrays have been used to classify tumors into clinically relevant subgroups. In this study, we have refined the previously defined subtypes of breast tumors that could be distinguished by their distinct patterns of gene expression. A total of 115 malignant breast tumors were analyzed by hierarchical clustering based on patterns of expression of 534 “intrinsic” genes and shown to subdivide into one basal-like, one ERBB2-overexpressing, two luminal-like, and one normal breast tissue-like subgroup. The genes used for classification were selected based on their similar expression levels between pairs of consecutive samples taken from the same tumor separated by 15 weeks of neoadjuvant treatment. Similar cluster analyses of two published, independent data sets representing different patient cohorts from different laboratories, uncovered some of the same breast cancer subtypes. In the one data set that included information on time to development of distant metastasis, subtypes were associated with significant differences in this clinical feature. By including a group of tumors from BRCA1 carriers in the analysis, we found that this genotype predisposes to the basal tumor subtype. Our results strongly support the idea that many of these breast tumor subtypes represent biologically distinct disease entities.
Platelet counts and aggregates in coronary artery disease.

Platelet counts and aggregates have been measured in arterial, coronary sinus and peripheral venous blood in groups of patients with and without coronary artery disease, and under various conditions associated with myocardial ischaemia. No changes in platelet counts were observed. An increase in platelet aggregates across the coronary vascular bed was observed during spontaneous or ergometrine-induced ischaemia, but not with pacing-induced angina nor at the onset of coronary occlusion causing infarction. Platelet aggregates were high in systemic blood samples from patients with frequent episodes of spontaneous angina but not in samples from patients with stable effort angina, nor were they increased with exercise-induced angina or after myocardial infarction. The findings suggest that platelet aggregates are found in coronary sinus blood when there is very severe proximal narrowing (but not complete occlusion) of a coronary artery sufficient to cause cardiac pain at rest, but not when proximal constriction is less severe and the ischaemia is pacing-induced. Increased platelet aggregates in systemic blood samples may be a marker of recent episodes of rest pain.
Is the Experience of Thermal Pain Genetics Dependent?

It is suggested that genetic variations explain a significant portion of the variability in pain perception; therefore, increased understanding of pain-related genetic influences may identify new targets for therapies and treatments. The relative contribution of the different genes to the variance in clinical and experimental pain responses remains unknown. It is suggested that the genetic contributions to pain perception vary across pain modalities. For example, it has been suggested that more than 60% of the variance in cold pressor responses can be explained by genetic factors; in comparison, only 26% of the variance in heat pain responses is explained by these variations. Thus, the selection of pain model might markedly influence the magnitude of the association between the pain phenotype and genetic variability. Thermal pain sensation is complex with multiple molecular and cellular mechanisms operating alone and in combination within the peripheral and central nervous system. It is thus highly probable that the thermal pain experience is affected by genetic variants in one or more of the pathways involved in the thermal pain signaling. This review aims to present and discuss some of the genetic variations that have previously been associated with different experimental thermal pain models.
Applications of Experiential Learning in Science Education Non-Formal Contexts

Education represents a process in constant evolution, which continuously adapts its structure and vision, objectives and strategies in order to successfully meet the challenges and significant changes occurring in society, but also in the psychical structure of its actors. As a suitable alternative to traditional learning, the experiential learning directly capitalizes skills and attitudes related to critical thinking and problem solving, being less anchored in mechanical learning and memorizing. The experiential learning includes learning by doing, through experience, through exploration and discovery, having the aim to teach the student how to learn, to develop his/her skills by individual work, to emphasize his/her creativity and originality, but also its self-confidence. The paper has an exploratory character, its aim being to discover how experiential learning can influence the student's motivation, knowledge transfer, creativity, self-confidence and how may be created learning opportunities, which can influence development of metacognitive skills, practical and independent work skills, exploratory skills and efficient learning through non-formal activities. The paper also highlights on the students’ perception related to their involvement in a series of non-formal activities, organized in the frame of the EU FP7 project entitled: “IRRESISTIBLE Including Responsible Research and Innovation in Cutting Edge Science and Inquiry-based Science Education to Improve Teacher's Ability of Bridging Learning Environments”, and dedicated to the promoting of cutting-edge scientific subjects, together with the disseminating of Responsible Research and Innovation (RRI) dimensions. The feed-back offered by the students who expressed their degree of interest and their openness to such activities led to the conclusion that those contexts could create proper opportunities to facilitate the knowledge transfer, emphasizing more on developing practical skills and producing a sustainable learning. © 2016 Published by Future Academy www.FutureAcademy. org.uk
StreamExplorer: A Multi-Stage System for Visually Exploring Events in Social Streams

Analyzing social streams is important for many applications, such as crisis management. However, the considerable diversity, increasing volume, and high dynamics of social streams of large events continue to be significant challenges that must be overcome to ensure effective exploration. We propose a novel framework by which to handle complex social streams on a budget PC. This framework features two components: 1) an online method to detect important time periods (i.e., subevents), and 2) a tailored GPU-assisted Self-Organizing Map (SOM) method, which clusters the tweets of subevents stably and efficiently. Based on the framework, we present StreamExplorer to facilitate the visual analysis, tracking, and comparison of a social stream at three levels. At a macroscopic level, StreamExplorer uses a new glyph-based timeline visualization, which presents a quick multi-faceted overview of the ebb and flow of a social stream. At a mesoscopic level, a map visualization is employed to visually summarize the social stream from either a topical or geographical aspect. At a microscopic level, users can employ interactive lenses to visually examine and explore the social stream from different perspectives. Two case studies and a task-based evaluation are used to demonstrate the effectiveness and usefulness of StreamExplorer.
Eastern Cape teachers’ beliefs of the nature of mathematics: Implications for the introduction of in-service mathematical literacy programmes for teachers

Various studies have shown that what teachers consider to be optimal ways of teaching mathematics is influenced by their beliefs about the nature of mathematics, and that it is advantageous to determine teachers’ conceptions of the nature of mathematics before developing curriculum interventions. With the imminent introduction of Mathematical Literacy in the FET phase in South Africa this study provides a snapshot of beliefs of teachers in the Eastern Cape, South Africa. Various methods were employed to stimulate teachers to both reflect on their beliefs and to make them explicit. A questionnaire was administered to 339 in-service teachers in urban and rural areas of the Eastern Cape. A sample of ninety-five of these teachers completed a second questionnaire based on videotapes of lessons recorded during the TIMSS (1995) study that they had viewed. These teachers also ranked their own teaching on a continuum ranging from traditional to constructivist approaches and provided explanations for their ranking. A further sub-sample of thirty-six teachers participated in individual interviews, which explored their perceptions of the nature of mathematics and their own teaching practice. In order to investigate whether these beliefs were mirrored in practice, four teachers were observed and videotaped in their classrooms. The data generated by this study suggest that the participating teachers’ espoused beliefs of the nature of mathematics tended to be innovative, and correlated with innovative views of teaching and learning; however these views were often not reflected in their practice. The implications that the apparent inability of teachers to translate their beliefs into practice have for the introduction of a contextual, problem-based Mathematical Literacy curriculum for teachers is explored.
Invaded range and competitive ability of the newly invasive Polistes dominula compared to that of its native congener species in the Western Cape, South Africa

The invasive European paper wasp Polistes dominula was first recorded in South Africa in 2008. Subsequently range expansion was recorded in 2012 and 2014, but it was still confined within the barrier of the Cape Fold Mountain Belt (CFMB), except for one instance thought to be human mediated. As yet no focussed research has been conducted on habitat preferences, activity period and the current invaded range of P. dominula. To determine habitat preferences and activity period, 40 sites of four habitat types (n=10 for each of urban, rural, fringe and natural) were monitored for foraging wasp activity for a period of 12 months (June 2013 – June 2014) in and around the town of Stellenbosch. P. dominula was found to prefer urban and fringe habitat types and was nearly absent from natural habitats. Its invaded range was determined by visiting towns one after the other from Kuilsriver (the first recorded locality of the species in South Africa) radiating outwards and searching for foraging wasps within the urban habitat type. Of the 27 towns visited P. dominula was found to be active in 13, one of which was outside the CFMB. Activity period was between September and May with a peak during March/April corresponding with seasonal temperature fluctuations. P. dominula preferred habitats in close proximity to human settlements where numerous sturdy nesting structures in the form of buildings are available. Future range expansion is therefore likely to manifest in cities and towns to the north and east of the current distribution range of this species. Introduction An estimated 480 000 non-native species have been introduced across the globe (Pimentel et al. 2001). Approximately 8818 of these have been introduced within the borders of South Africa (Pimentel et al. 2001). Estimating the environmental impact brought on by a nonnative species entering a new habitat can be difficult (Pimentel et al. 2001). In the Fynbos biome of the Western Cape Province alone, 80% of endangered species are at risk due to invasion by non-native species (Armstrong 1995). However, the bulk of the research on the effects of invasive species is aimed at more conspicuous organisms like flora and larger fauna, while more inconspicuous organisms such as insects are relatively understudied (McGeoch et al. 2011).
Investigating the Effects of Metacognitive Instruction in Learning Primary School Science in Some Schools in Ethiopia

SBHATU, DESTA BERHE. Investigating the Effects of Metacognitive Instruction in Learning Primary School Science in Some Schools in Ethiopia. (Under the Direction of Professor John E. Penick.) Metacognition is increasingly recognized as an important component in successful learning. In science, metacognitive instructional interventions have been successfully incorporated to promote conceptual change learning, facilitate negotiating and constructing of meanings, and foster reading and problem solving abilities of learners. The present study investigated the contribution of three metacognitive instructional methods, namely graphic organizers, metacognitive reflection, and metacognitive reading in learning science among primary school students (age 10-14 years) in Mekelle, Ethiopia. The metacognitive instructional methods were believed to be efficient to introduce and transform learner-centeredness in science instruction under Ethiopia’s primary school settings by allowing students to think productively and regulate their own learning. Qualitative study indicated that the metacognitive instructional methods fostered student conceptual understanding of science topics and enhanced active student participation. Quantitative study of post-scores of Immediate test-groups revealed that graphic organizers had some contribution in helping students perform better in ‘application’ type tests. Metacognitive reflection activities enabled students to perform better in ‘application’ and ‘transfer’ type tests as well as enhancing mean post-test scores. Metacognitive reading activities did not yield any apparent effects on postintervention tests. The effects of the metacognitive methods were diminished among Delayed post-test groups. INVESTIGATING THE EFFECTS OF METACOGNITIVE INSTRUCTION IN LEARNING PRIMARY SCHOOL SCIENCE IN SOME SCHOOLS IN ETHIOPIA BY DESTA BERHE SBHATU A Dissertation Submitted to the Graduate Faculty of North Carolina State University in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy
Ultraviolet Fe ii emission in fainter quasars: luminosity dependences, and the influence of environments

We investigate the strength of ultraviolet Fe ii emission in fainter quasars compared with brighter quasars for 1.0 ≤ z ≤ 1.8, using the Sloan Digital Sky Survey (SDSS) DR7QSO catalogue and spectra of Schneider et al., and the SDSS Faint Quasar Survey (SFQS) catalogue and spectra of Jiang et al. We quantify the strength of the UV Fe ii emission using the W2400 equivalent width of Weymann et al., which is defined between two rest-frame continuum windows at 2240–2255 and 2665–2695 A. The main results are the following. (1) We find that for W2400 ≳ 25 A there is a universal (i.e. for quasars in general) strengthening of W2400 with decreasing intrinsic luminosity, L3000. (2) In conjunction with previous work by Clowes et al., we find that there is a further, differential, strengthening of W2400 with decreasing L3000 for those quasars that are members of Large Quasar Groups (LQGs). (3) We find that increasingly strong W2400 tends to be associated with decreasing full width at half maximum (FWHM) of the neighbouring Mg ii λ2798 broad emission line. (4) We suggest that the dependence of W2400 on L3000 arises from Lyα fluorescence. (5) We find that stronger W2400 tends to be associated with smaller virial estimates from Shen et al. of the mass of the central black hole, by a factor of ∼2 between the ultrastrong emitters and the weak. Stronger W2400 emission would correspond to smaller black holes that are still growing. The differential effect for LQG members might then arise from preferentially younger quasars in the LQG environments.
Factors associated with child sexual abuse in Tanzania: a qualitative study

Background: Child sexual abuse (CSA) is one of the most pervasive occurrences which are reported all over the world. It often goes unnoticed and undocumented due to surrounding taboos; its sensitivity in nature and affects the less powerful population. Anecdote information is available on the nature and extent of sexual abuse among children in Tanzania. The aim of this study was to explore factors, forms, context of abuse and perpetrators of child sex abuse in selected regions of Tanzania. Methods : Key informant interviews were conducted among adults including parents of the victims to explore factors associated with sexual abuse of children under 10 years old in Tanzania. The interview guide centred on factors for child sexual abuse, the type of perpetrators and the context into which these abuses take place. Results: There were incidences of child sexual abuse in Tanzania and the major forms were anal and vaginal penetration, and the most affected were girls. The abuses were rarely reported due to shame and embarrassment faced by the affected children and parents. The causes of child sexual abuse were poverty, ambitions and moral degradation, myths and beliefs, urbanization, foreign culture and poor parental care. Incidents of CSA were reported to occur in perpetrators’ homes and in semi-finished housing structures, madrassa and recreational venues where children can freely access entertainment by watching movies. These acts were committed by people in position of power, close relationship and trusted by the children. Contexts where child sexual abuses occur included overcrowded living spaces and social activities that go on late into the night. Conclusion : We recommend for strengthened interventions at different levels within the society to address the root causes and different contexts in which child sex abuse occurs. Increased awareness of the root causes should go hand in hand with measures to encourage parents and survivors to report incidents to relevant authorities timely as they occur.
Estimating the effects of nutrition label use on Canadian consumer diet‐health concerns using propensity score matching

The overarching goal of nutrition labelling is to transform intrinsic credence attributes into searchable cues, which would enable consumers to make informed food choices at lower search costs. This study estimates the impact of nutrition label usage on Canadian consumers’ (n = 8,114) perceived diet-health concerns using alternative propensity score matching (PSM) techniques. We apply a series of tests and sensitivity analyses to overcome issues of endogeneity and selection bias frequently found in studies of diet-health behaviour and to validate the impact of exposure to nutrition facts labels for users vs. non-users. Our results support the notion that consumer uncertainty and related food-health concerns are linked to their information behaviour, but not in straightforward manner. Dominant subjective food attributes, such as taste, convenience and affordability, may in fact outweigh the benefits of information about healthier, alternative food choices. In order to change dietary health behaviour, food manufacturer and policy makers alike need to adopt communication instruments that better account for differences in preferences, shopping habits and overall usage patterns of nutrition labelling information.
Investor Overconfidence and the Increase in Idiosyncratic Risk

This paper examines the relation between investor overconfidence and the idiosyncratic volatility of stock returns. We use investor sentiment, stock turnover, stock misvaluation, and institutional ownership to measure the influence of investor overconfidence on stocks, and find that idiosyncratic volatility is correlated with investor overconfidence proxies in both cross-sectional and time-series tests. The results are robust when other well-documented determinants of idiosyncratic volatility such as firm size, age, stock price, profitability, and growth options are controlled. We thus conclude that investor overconfidence contributes to the dynamics of idiosyncratic volatility both across stocks and over time.