Miracle-dz/UniFAR-FTUs huggingface dataset:
The general error correction model in practice

Enns et al. respond to recent work by Grant and Lebo and Lebo and Grant that raises a number of concerns with political scientists’ use of the general error correction model (GECM). While agreeing with the particular rules one should apply when using unit root data in the GECM, Enns et al. still advocate procedures that will lead researchers astray. Most especially, they fail to recognize the difficulty in interpreting the GECM’s “error correction coefficient. ” Without being certain of the univariate properties of one’s data it is extremely difficult (or perhaps impossible) to know whether or not cointegration exists and error correction is occurring. We demonstrate the crucial differences for the GECM between having evidence of a unit root (from Dickey–Fuller tests) versus actually having a unit root. Looking at simulations and two applied examples we show how overblown findings of error correction await the uncareful researcher.
Correlation between intake of omega-3 fatty acids and depressive and anxiety symptoms during pregnancy

Introduction. Anxiety and depression during pregnancy are disabling disorders associated to complications during the pregnancy, delivery, and postpartum period, with a significant prevalence, between 9 and 20%, hence its importance. Nutritional factors, such as omega-3 fatty acids (ω-3FA) deficiency, have been related with both disorders during pregnancy, especially docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Objective. To evaluate the association between dietary intake of EPA and DHA, and anxiety symptoms (AS) and depressive symptoms (DS) in Mexican pregnant women. Method. The sample consisted of 151 women in the second trimester of pregnancy. Instruments included a Food Frequency Questionnaire, the Trait Anxiety Inventory, and the Edinburgh Postnatal Depression Scale. Results. A daily intake of DHA and EPA of 70 mg/d and 30 mg/d, respectively, was found. The prevalence of AS was 44.4%, and 17.9% for DS. We also found the correlation negatively moderate between dietary intake of DHA and EPA and AS ( p = .003, p = .017) and DS ( p = .001, p = .020) in the group of women who had a severely insufficient intake of ω-3FA. Discussion and conclusion. The statistical significance shows a negative correlation between variables and the dietary intake of ω-3FA explains in a very small percentage the variability of AS and DS, according to their coefficient of determination. These results suggest the need for an investigation of this relationship through interventional studies.
Reassessing Twitter’s Agenda-Building Power

This study examined the relationship between elite news media agendas and campaign agendas during the 2016 presidential primary season. Computer-assisted content analysis was used to assess issue emphasis within Twitter feeds of U.S. presidential primary candidates and their campaigns as well as the nation’s top newspapers. The relationship between the overall Twitter agenda and that of newspapers, as well as the influence of front-runners Clinton, Cruz, Sanders, and Trump, was investigated using time series analysis. Aggregate and candidate-specific findings reveal some reciprocal relationships, but overall greater influence of newspapers on the Twitter agenda was detected. Findings suggest that Twitter has the potential to break free from and influence traditional media gatekeeping.
Learning Parsimonious Classification Rules from Gene Expression Data Using Bayesian Networks with Local Structure

The comprehensibility of good predictive models learned from high-dimensional gene expression data is attractive because it can lead to biomarker discovery. Several good classifiers provide comparable predictive performance but differ in their abilities to summarize the observed data. We extend a Bayesian Rule Learning (BRL-GSS) algorithm, previously shown to be a significantly better predictor than other classical approaches in this domain. It searches a space of Bayesian networks using a decision tree representation of its parameters with global constraints, and infers a set of IF-THEN rules. The number of parameters and therefore the number of rules are combinatorial to the number of predictor variables in the model. We relax these global constraints to a more generalizable local structure (BRL-LSS). BRL-LSS entails more parsimonious set of rules because it does not have to generate all combinatorial rules. The search space of local structures is much richer than the space of global structures. We design the BRL-LSS with the same worst-case time-complexity as BRL-GSS while exploring a richer and more complex model space. We measure predictive performance using Area Under the ROC curve (AUC) and Accuracy. We measure model parsimony performance by noting the average number of rules and variables needed to describe the observed data. We evaluate the predictive and parsimony performance of BRL-GSS, BRL-LSS and the state-of-the-art C4.5 decision tree algorithm, across 10-fold cross-validation using ten microarray gene-expression diagnostic datasets. In these experiments, we observe that BRL-LSS is similar to BRL-GSS in terms of predictive performance, while generating a much more parsimonious set of rules to explain the same observed data. BRL-LSS also needs fewer variables than C4.5 to explain the data with similar predictive performance. We also conduct a feasibility study to demonstrate the general applicability of our BRL methods on the newer RNA sequencing gene-expression data.
No Positive Effect of Acid Etching or Plasma Cleaning on Osseointegration of Titanium Implants in a Canine Femoral Condyle Press-Fit Model

Purpose: Implant surface treatments that improve early osseointegration may prove useful in long-term survival of uncemented implants. We investigated Acid Etching and Plasma Cleaning on titanium implants. Methods: In a randomized, paired animal study, four porous coated Ti implants were inserted into the femurs of each of ten dogs. PC (Porous Coating; control) PC+PSHA (Plasma Sprayed Hydroxyapatite; positive control) PC+ET (Acid Etch) PC+ET+PLCN (Plasma Cleaning) After four weeks mechanical fixation was evaluated by push-out test and osseointegration by histomorphometry. Results: The PSHA-coated implants were better osseointegrated than the three other groups on outer surface implant porosity (p<0.05) while there was no statistical difference in deep surface implant porosity when compared with nontreated implant. Within the deep surface implant porosity, there was more newly formed bone in the control group compared to the ET and ET+PCLN groups (p<0.05). In all compared groups, there was no statistical difference in any biomechanical parameter. Conclusions: In terms of osseointegration on outer surface implant porosity PC+PSHA was superior to the other three groups. Neither the acid etching nor the plasma cleaning offered any advantage in terms of implant osseointegration. There was no statistical difference in any of the biomechanical parameters among all groups in the press-fit model at 4 weeks of evaluation time.
Decaying cosmic ray nuclei in the local interstellar medium

Secondary radioactive isotopes that are used for the determination of cosmic ray age, have relatively short decay lifetimes. The measured abundance of these isotopes at low energies is representative of the cosmic ray diffusion and the gas distribution in a region of a few hundred parsecs around the Sun. We show how to determine the local cosmic ray diffusion coefficient in the Galaxy using the data on decaying cosmic ray nuclei.
An Operant Analysis of Joint Attention Skills

Joint attention, a synchronizing of the attention of two or more persons, has been an increasing focus of research in cognitive developmental psychology. Research in this area has progressed mainly outside of behavior analysis, and behavior-analytic research and theory has tended to ignore the work on joint attention. It is argued here, on the one hand, that behavior-analytic work on verbal behavior with children with autism needs to integrate the research body on joint attention. On the other hand, research on joint attention should integrate behavior-analytic principles to produce more effective analyses of basic processes involved. An operant analysis of phenomena typically considered under the heading of joint attention is followed by examples of training protocols aimed at teaching joint attention skills, such as social referencing, monitoring, gaze following, and such skills interwoven with mands and with tacts. Finally, certain research questions are pointed out.
Gene-Swapping Mediates Host Specificity among Symbiotic Bacteria in a Beneficial Symbiosis

Environmentally acquired beneficial associations are comprised of a wide variety of symbiotic species that vary both genetically and phenotypically, and therefore have differential colonization abilities, even when symbionts are of the same species. Strain variation is common among conspecific hosts, where subtle differences can lead to competitive exclusion between closely related strains. One example where symbiont specificity is observed is in the sepiolid squid-Vibrio mutualism, where competitive dominance exists among V. fischeri isolates due to subtle genetic differences between strains. Although key symbiotic loci are responsible for the establishment of this association, the genetic mechanisms that dictate strain specificity are not fully understood. We examined several symbiotic loci (lux-bioluminescence, pil = pili, and msh-mannose sensitive hemagglutinin) from mutualistic V. fischeri strains isolated from two geographically distinct squid host species (Euprymna tasmanica-Australia and E. scolopes-Hawaii) to determine whether slight genetic differences regulated host specificity. Through colonization studies performed in naïve squid hatchlings from both hosts, we found that all loci examined are important for specificity and host recognition. Complementation of null mutations in non-native V. fischeri with loci from the native V. fischeri caused a gain in fitness, resulting in competitive dominance in the non-native host. The competitive ability of these symbiotic loci depended upon the locus tested and the specific squid species in which colonization was measured. Our results demonstrate that multiple bacterial genetic elements can determine V. fischeri strain specificity between two closely related squid hosts, indicating how important genetic variation is for regulating conspecific beneficial interactions that are acquired from the environment.
Acceptance of Social Media by Organizational Users - Testing the Impact of System Design Features

As more business-to-business organizations consider using social media to attract customers, the acceptance of social media technology among employees becomes crucial. We assume particular factors to matter for organizational users as compared to private users. Study 1 which is based on 46 in-depth interviews explores six system design features that are critical for social media usage among organizations. We document the role of (1) information sharing, (2) internal communication, (3) customer feedback and dialogue, (4) content control, (5) internal data security, and (6) system integrity concerns in social media technology assessments. We test the developed conceptual model in study 2 using survey data from 126 organizations. Results indicate that system design features show positive and negative effects on usefulness and ease of use. We find strong negative responses of system design features on anxiety associated with social media usage and perception of emotional conviction.
Toward an assessment of marginality in democratic systems: The Charlie Hebdo debate in the United Kingdom

This article offers a theoretical and empirical investigation of marginality of actors and ideas in democratic systems. We do so with respect to the extensive public debate that ensued from the Charlie Hebdo terrorist attacks of January 2015. Using content analytical data retrieved from The Guardian, we assess the degree and nature of marginality as indicated by the presence of different types of intervention in the public debate. Our findings show that women have very limited visibility; religious and minority groups—particularly Muslims—are sidestepped; and actors challenging the dominant securitisation narrative are systematically neglected by those holding dominant positions. We argue for greater attention to the problem of marginality and introduce the Maximin principle of marginality as a means to address this issue in analyses of democratic systems.
Empirical Study of Digital Poverty: A Case Study of a University of Technology in South Africa

This research evaluates the availability and use of Information and Communications Technology (ICT) by students from disadvantaged and privileged families studying Computer Science at a University of Technology in South Africa. A questionnaire was distributed to a stratified random sample of 50 firstand 20 thirdyear students. Descriptive statistics were used to analyze and present the results of the study. The results suggested that a low level of education is associated with digitally poor people. Results of the research also proposed that men had more opportunities of using ICTs than women. The more economically poor a family was, the more digital poor it was. The research also showed that living in the rural areas seems to decrease the probability of being (more) digitalized. The results of the study were later used to create a framework for assessing the degree of ICT usage and to group the population into digital poverty levels.
An EAP Program and Students’ Success at a Canadian University

Many universities have instituted intensive English for Academic Purposes (EAP) programs to support international students. This qualitative study used interviews to gain insights into the experiences of 8 non-native English speaking (NNES) students who completed an EAP program before they enrolled in disciplinary courses at a Canadian university. We followed and interviewed these students as they studied in the EAP program and then moved through the first term of university to identify how the EAP program prepared them for disciplinary courses. Results of the study illustrate that students’ responses to the EAP program were mostly positive; all 8 students reported improvements and increased confidence in speaking and writing as they embarked on university classes. However, the participants reported challenges in their first term of university, including difficulty in understanding lectures, completing more complex writing tasks, adjusting to new expectations, and seeking social or peer support. The participants reported that all these challenges would have been greater had they not taken the EAP courses. Recommendations based on the findings are discussed. Plusieurs universites ont etabli des programmes intensifs d’anglais academique pour appuyer les etudiants internationaux. Cette etude qualitative s’est basee sur des entrevues pour obtenir un apercu des experiences de 8 etudiants n’ayant pas l’anglais comme langue maternelle qui ont complete un programme d’anglais academique avant de s’inscrire a des cours lies a une discipline academique dans une universite canadienne. Nous avons suivi ces etudiants et les avons interviewes pendant qu’ils suivaient le programme d’anglais academique et ensuite lors de leur premier semestre d’universite pour identifier dans quelle mesure le programme d’anglais academique les avait prepares pour les cours reguliers. Les resultats revelent que les etudiants ont reagi de facon surtout positive au programme d’anglais academique; tous les 8 etudiants ont signale des ameliorations et une confiance accrue face a l’anglais oral et ecrit quand ils avaient commence leurs cours universitaires. Toutefois, les participants ont evoque des defis pendant leur premier semestre a l’universite, y compris de la difficulte liee a la compre- hension des cours, les tâches ecrites plus complexes, l’ajustement aux nouvelles attentes et la recherche d’appui social ou des pairs. Les participants ont declare que ces defis auraient ete encore plus importants sans les cours d’anglais academique qu’ils avaient suivis. Nous discutons de recommandations decoulant des resultats.
Migration and deformation of bubbles rising in a wall-bounded shear flow at finite Reynolds number

The quasi-steady migration and deformation of bubbles rising in a wall-bounded linear shear flow are investigated experimentally in the low-but-finite-Reynolds-number regime. A travelling optical device that follows the bubble is used for this purpose. This apparatus allows us to determine accurately the bubble radius, contour and rising speed, together with the distance between the bubble and the wall. Thereby the transverse component of the hydrodynamic force is obtained for Reynolds numbers Re (based on the bubble diameter and slip velocity of the bubble in the undisturbed shear flow) less than 5. The results indicate that in the range 0.5 < Re < 1.5, the transverse force acting on a spherical bubble agrees well with an extension of the theoretical solution obtained by McLaughlin (J. Fluid Mech., vol. 246, 1993, pp. 249–265) for rigid spheres, whereas it becomes larger than the theoretical prediction for Re > 1.5. In the regime in which bubble deformation is significant, the shape of the bubble and the deformation-induced transverse force are determined both experimentally and computationally, using a spectral boundary element method. Both estimates are found to be in good agreement with each other, while the theory of Magnaudet, Takagi & Legendre (J. Fluid Mech., vol. 476, 2003, pp. 115–157) is found to predict accurately the deformation but fails to predict quantitatively the deformation-induced transverse force.
Breaking the silence : teachers speak out about classroom behavioural problems : creating a positive learning environment in middle school classrooms - it can be done!

Too many teachers are struggling with students’ disengagement and behavioural problems in the classroom despite extensive research findings available to them on how to create a positive, harmonious learning environment: Why is this so? The aim of this research was to understand the realities faced by frontline practitioners particularly in middle school in order (1) to identify the barriers that limit a teacher’s chances of success in creating a positive learning environment and (2) to search for the ‘right drivers’ and ultimately the actions, sometimes small, that as ‘tipping points ‘can lead to significant improvements in the classroom. A qualitative methodology, namely a constructivist form of grounded theory was selected for this exploratory research study in order to develop insights and create a theory for action. The goal was to capture teachers’ voice and to use my own reflections and voice in the research. It was found that the silence about classroom behavioural problems needs to be addressed through a school culture of transparency, openness and collegial support, and the importance of classroom management needs to be recognised as a major teaching skill at the teacher, school and system level. A balanced leadership approach is recommended based (1) essentially on prevention but also (2) on positive, respectful intervention through logical consequences when preventative measures are insufficient to guarantee a lesson free from student misbehavior, and (3) on support provided to students with more challenging behaviours in order to assist them with the development of self discipline. It is the contention of this thesis that creating positive classroom learning environments is certainly achievable, and this reasonably quickly.
Ultraviolet Radiation-Induced Skin Aging: The Role of DNA Damage and Oxidative Stress in Epidermal Stem Cell Damage Mediated Skin Aging

Skin is the largest human organ. Skin continually reconstructs itself to ensure its viability, integrity, and ability to provide protection for the body. Some areas of skin are continuously exposed to a variety of environmental stressors that can inflict direct and indirect damage to skin cell DNA. Skin homeostasis is maintained by mesenchymal stem cells in inner layer dermis and epidermal stem cells (ESCs) in the outer layer epidermis. Reduction of skin stem cell number and function has been linked to impaired skin homeostasis (e.g., skin premature aging and skin cancers). Skin stem cells, with self-renewal capability and multipotency, are frequently affected by environment. Ultraviolet radiation (UVR), a major cause of stem cell DNA damage, can contribute to depletion of stem cells (ESCs and mesenchymal stem cells) and damage of stem cell niche, eventually leading to photoinduced skin aging. In this review, we discuss the role of UV-induced DNA damage and oxidative stress in the skin stem cell aging in order to gain insights into the pathogenesis and develop a way to reduce photoaging of skin cells.
The Witt group of real algebraic varieties

The purpose of this paper is to compare the algebraic Witt group W(V) of quadratic forms for an algebraic variety V over R with a new topological invariant, WR(VC) , based on symmetric forms on Real vector bundles (in the sense of Atiyah) on the space of complex points of V . This invariant lies between W(V) and the group KO(VR) of R ‐linear topological vector bundles on the space VR of real points of V .
Meningiomas in pregnancy: a clinicopathologic study of 17 cases.

BACKGROUND Dramatic growth of meningiomas is occasionally encountered during pregnancy. While cell proliferation is often assumed, hemodynamic changes have also been touted as a cause. OBJECTIVE We identified 17 meningiomas resected during pregnancy or within 3 weeks post-partum and characterized them to determine the cause of occasional rapid growth in pregnancy. METHODS Seventeen tumors were identified from searches at 4 university centers. All available clinical records, radiology images, and tissue specimens were reviewed, with immunohistochemical studies performed as needed. RESULTS Sixteen patients underwent tumor resection and 1 died of complications prior to surgery. Average patient age was 32 years. Nine experienced onset of symptoms in the third trimester or within 8 days post-partum. Principle physical findings included visual complaints (59%) and cranial nerve palsies (29%). Ten tumors (59%) were located in the skull base region. The Ki-67 labeling index was low (0.5-3.6%) in 11 of 13 benign (grade I) tumors and elevated (11-23.2%) in 3 of 4 atypical (grade II) meningiomas. Eight (50%) tumors featured hypervascularity with at least focal CD34-positive hemangioma-like microvasculature. Fourteen (82%) showed evidence of intra- and/or extracellular edema, 1 so extensive that its meningothelial nature was not apparent. Five tumors (29%) exhibited intratumoral hemorrhage and/or necrosis. CONCLUSION Our series suggests that pregnancy-associated meningiomas located in the skull base are likely to require surgical intervention for visual complaints and cranial nerve palsies. The rapid tumor growth is more often due to potentially reversible hemodynamic changes rather than hormone-induced cellular proliferation.