The emergence of doctoral programmes in the Colombian higher education system: Trends and challenges

The international literature contains few formal analyses of the state of Colombian higher education and its most critical issues. This article systematically and comparatively analyzes the emergence of Colombian doctoral programmes within a national and international context. It shows that, while Colombia has experienced a significant growth in the number of Ph.D. graduates per million people over the last decade, it continues to lag behind other Latin American countries. Further, it is critical for Colombia to increase funding for doctoral training, both by increasing the number of scholarships for graduate studies and by improving the mobility of researchers and strengthening the infrastructure of doctoral programmes. Increasing its numbers of Ph.D. holders is vital if Colombia is to succeed in entering the knowledge-based economy.     

Weight changes in children in foster care for 1 year

Objective

The aims of this study of predominately racial/ethnic minority children in foster care (N = 360, birth to 19 years old) in Los Angeles, CA were to examine the (1) prevalence of obesity (≥95 percentile) and overweight/obese (≥85 percentile) upon entrance to foster care (T1) and after 1 year in foster care (T2); (2) comparison of high weight categories to national statistics; (3) relationship of changes in weight status to age, reason for entry into foster care, and placement.

Methods

Chi-square test and McNemar test comparing paired proportions were used to determine whether there were significant changes in the proportion of high weight categories between T1 and T2. Chi-square test or Fisher's exact test were used to evaluate the association between age, placement, and reason for foster care with the change in weight category. Changes in weight were categorized as (1) decreased in weight, (2) remained at overweight or obese, (3) increased in weight, or (4) remained normal.

Results

The proportion of obese and obese/overweight children between ages 2 and 5 were significantly lower at T2 than T1. There were no significant changes in the prevalence of obesity for the total population at T2. Children age 6 or older had a higher prevalence of obesity and overweight/obesity compared to national statistics. Of children at all ages, 64.7% of children of all ages entered foster care with a normal weight and stayed in the normal range during their first year in foster care, 12.2% decreased their weight, 15.4% remained overweight or obese, and 7.7% increased their weight. Age and parental substance use was related to change in weight category from T1 to T2.

Conclusion

Children did not become more overweight or obese in foster care; however 28% of the children were obese or overweight upon entry into foster care. Children who are 6 years or older and obese upon entering foster care should be targeted for weight reduction. The pediatric community and child welfare system need to work together by including weight percentiles in the foster care file and training/monitoring child welfare caregivers in weight reduction interventions.     

Dimensions as Virtual Items: Improving the predictive ability of top-N recommender systems

Traditionally, recommender systems for the web deal with applications that have two dimensions, users and items. Based on access data that relate these dimensions, a recommendation model can be built and used to identify a set of N items that will be of interest to a certain user. In this paper we propose a multidimensional approach, called DaVI (Dimensions as Virtual Items), that consists in inserting contextual and background information as new user–item pairs. The main advantage of this approach is that it can be applied in combination with several existing two-dimensional recommendation algorithms. To evaluate its effectiveness, we used the DaVI approach with two different top-N recommender algorithms, Item-based Collaborative Filtering and Association Rules based, and ran an extensive set of experiments in three different real world data sets. In addition, we have also compared our approach to the previously introduced combined reduction and weight post-filtering approaches. The empirical results strongly indicate that our approach enables the application of existing two-dimensional recommendation algorithms in multidimensional data, exploiting the useful information of these data to improve the predictive ability of top-N recommender systems.     

Effects of AM3 (Inmunoferon®) on increased serum concentrations of interleukin-6 and tumour necrosis factor receptors I and II in cyclists

Abstract

The aims of this study were to examine the changes in plasma concentrations of inflammatory cytokines induced by training and competition in professional cyclists. We report the serum concentrations of interleukin-6 (IL-6), tumour necrosis factor alpha (TNF-α), tumour necrosis factor receptors I and II (TNFR-I and -II) in a prospective, randomized, double-blind trial involving the administration of AM3 (Inmunoferon®), an oral booster immunomodulator, or placebo to 16 professional cyclists (n=8 in each group) for 65 consecutive days. Serum was collected just before treatment began (baseline), at the end of pre-competition training, before the mountain stage of the competition (60 days), 4 h after finishing this stage (62 days), and 18 h after the fifth and last day of competition (65 days). To determine the normal levels of cytokines and soluble TNF receptors, individual samples from 14 moderately trained healthy controls were studied. After 60 days of training, the serum concentrations of IL-6 did not differ significantly from those at the beginning of the study for either group of cyclists (placebo and AM3). A significant rise was seen in IL-6 concentrations in both the AM3 and placebo groups at 62 days, 4 h after finishing the mountain stage. The increase was significantly greater in the placebo group than in the AM3 group. At 65 days of treatment, 18 h after the fifth and last day of competition, IL-6 concentrations were similar to those recorded at the end of the training, but were significantly higher in the placebo group than in the AM3 group. At the end of training, serum TNFR-I concentrations in both groups of cyclists were significantly lower than at baseline. The concentrations of serum TNFR-I and -II both 4 h after finishing the mountain stage and 18 h after the fifth and last day of competition were significantly higher than those recorded after training in both groups. Professional cycling competition is associated with increases in serum IL-6 and TNFR-I and -II concentrations. Inmunoferon treatment reduced significantly the concentrations of IL-6 but not those of TNFR-I and -II.     

Agreement in activity energy expenditure assessed by accelerometer and self-report in adolescents: Variation by sex,age, and weight status

Abstract

The agreement between self-reported and objective estimates of activity energy expenditure was evaluated in adolescents by age, sex, and weight status. Altogether, 403 participants (217 females, 186 males) aged 13–16 years completed a 3-day physical activity diary and wore a GT1M accelerometer on the same days. Partial correlations (controlling for body mass) were used to determine associations between estimated activity energy expenditure (kcal · min^?1) from the diary and accelerometry. Differences in the magnitude of the correlations were examined using Fisher's r to z transformations. Bland–Altman procedures were used to determine concordance between the self-reported and objective estimates. Partial correlations between assessments of activity energy expenditure (kcal · min^?1) did not differ significantly by age (13–14 years: r = 0.41; 15–16 years: r = 0.42) or weight status (normal weight: r = 0.42; overweight: r = 0.39). The magnitude of the association was significantly affected by sex (Δr = 0.11; P < 0.05). The agreement was significantly higher in males than in females. The relationship between activity energy expenditure assessed by the objective method and the 3-day diary was moderate (controlling for weight, correlations ranged between 0.33 and 0.44). However, the 3-day diary revealed less agreement in specific group analyses; it markedly underestimated activity energy expenditure in overweight/obese and older adolescents. The assessment of activity energy expenditure is complex and may require a combination of methods.     

The role of location and social strength for friendship prediction in location-based social networks

Recent advances in data mining and machine learning techniques are focused on exploiting location data. These advances, combined with the increased availability of location-acquisition technology, have encouraged social networking services to offer to their users different ways to share their location information. These social networks, called location-based social networks (LBSNs), have attracted millions of users and the attention of the research community. One fundamental task in the LBSN context is the friendship prediction due to its role in different applications such as recommendation systems. In the literature exists a variety of friendship prediction methods for LBSNs, but most of them give more importance to the location information of users and disregard the strength of relationships existing between these users. The contributions of this article are threefold, we: 1) carried out a comprehensive survey of methods for friendship prediction in LBSNs and proposed a taxonomy to organize the existing methods; 2) put forward a proposal of five new methods addressing gaps identified in our survey while striving to find a balance between optimizing computational resources and improving the predictive power; and 3) used a comprehensive evaluation to quantify the prediction abilities of ten current methods and our five proposals and selected the top-5 friendship prediction methods for LBSNs. We thus present a general panorama of friendship prediction task in the LBSN domain with balanced depth so as to facilitate research and real-world application design regarding this important issue.     

Longitudinal associations between motor competence and different physical activity intensities: LabMed physical activity study

An appropriated level of motor competence is essential for children´s healthy growth and development and a key factor in the promotion of lifelong active lifestyles and health.

The purpose of this study was to examine associations between motor competence and different physical activity intensities (light, moderate, moderate-to-vigorous and vigorous physical activity), as well as total physical activity, over a two-year period, in adolescents. The sample comprised of 103 adolescents (13.49 ± 0.87 years, 53 girls), from the north of Portugal. Motor competence was evaluated with the body coordination test, Körperkoordination-Test-für-Kinder. Physical activity was objectively assessed with GT1M accelerometers (ActiGraph, Pensacola, FL, USA). Physical activity variables were expressed as proportions of accelerometer wear time. Regression analyses showed positive longitudinal associations between motor competence at baseline and moderate physical activity (B = 0.0033, p = 0.018), moderate-to-vigorous physical activity (B = 0.0052, p = 0.024) and total physical activity (B = 0.067, p = 0.040) at follow up, after adjustments for age, sex, the corresponding physical activity intensity at baseline, body mass index, pubertal stage and socioeconomic status. Our ?ndings highlight the importance of motor competence development to promote moderate-to-vigorous physical activity during adolescence.     

Potencial De La Educación a Distancia Para Reducir Brechas De Aprendizaje En Educación Superior: Una Mirada Al Caso Colombiano

ABSTRACT

One of the main needs of Latin America, besides education coverage, is to reduce learning gaps in higher education. In order to respond to such need, many strategies have been designed, worldwide, to impact the demand and provision of higher education programs. Among these strategies we can find grants and scholarships, financial aids, and others. Many have been the options that have been proposed to raise the provision of higher education programs, such as offering technology-supported education modalities like blended-learning, Massive Open Online Courses (MOOCs), and distance and online education. This paper aims to explore the potential of the provision of distance education programs to close learning gaps in Colombia’s higher education. In order to do so, we present an estimatation of the effects that students and programs characteristics can have on the results of the test “Saber PRO” (a Colombian standardized test that measures the level of competences developed by students in different higher education programs). This estimation was done applying a mixed model (Hierarchical Linear Modeling-HLM) based on the information of 451,358 students who were assessed in their last phase of their university major. Data were collected from 2016 to 2018.

The econometrics estimations show that controlling individuals’ backgrounds and the characteristics of different academic programs, the variables that were highly associated with the reduction of learning gaps among individuals registered in distance programs compared to face-to-face programs are the students’ age and their cognitive backgrounds (grades in standardized tests taken before their undergraduate studies). The results show that we could expect distance education to become an efficient mechanism to contribute to the reduction of learning gaps in higher education. The quantitative findings suggest a series of research questions that invite to reflect about the potential of distance education in medium-income countries.     

A Prospect-Guided global query expansion strategy using word embeddings

The effectiveness of query expansion methods depends essentially on identifying good candidates, or prospects, semantically related to query terms. Word embeddings have been used recently in an attempt to address this problem. Nevertheless query disambiguation is still necessary as the semantic relatedness of each word in the corpus is modeled, but choosing the right terms for expansion from the standpoint of the un-modeled query semantics remains an open issue. In this paper we propose a novel query expansion method using word embeddings that models the global query semantics from the standpoint of prospect vocabulary terms. The proposed method allows to explore query-vocabulary semantic closeness in such a way that new terms, semantically related to more relevant topics, are elicited and added in function of the query as a whole. The method includes candidates pooling strategies that address disambiguation issues without using exogenous resources. We tested our method with three topic sets over CLEF corpora and compared it across different Information Retrieval models and against another expansion technique using word embeddings as well. Our experiments indicate that our method achieves significant results that outperform the baselines, improving both recall and precision metrics without relevance feedback.