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This paper aims to develop a stable gel-type lubricant emulating commercial conditions. This encompassed rheological and tribological assessments, alongside field trials on the Medellín tram system.

The gel-type lubricant with graphite and aluminum powder is synthesized. Rheological tests, viscosity measurements and linear viscoelastic regime assessments are conducted. Subsequently, tribological analyses encompassing four-ball and twin disc methods are executed. Finally, real-world testing is performed on the Medellín tram system.

An achieved lubricant met the stipulated criteria, yielding innovative insights into the interaction of graphite and aluminum powder additives under varying tests.

Novel findings are unveiled regarding the interaction of graphite and aluminum powder additives in tribological, rheological and real-world trials. In addition, the wear behavior of polymers is observed, along with the potential utilization of such additives in tramway systems.

The purpose of this paper is to investigate the relationship between career ambition – defined as high achievement motivation and strong career orientation – and both extrinsic (salary, position) and intrinsic success (job satisfaction, goal attainment) of psychologists. Over and above this, the authors explore whether extrinsic success predicts intrinsic success or vice versa.

In order to analyze the impact of career ambition on extrinsic and intrinsic success, the authors conducted two online studies with psychology graduates – a cross-sectional study (Study 1; n=119) and a longitudinal one (Study 2; n=63; two-three years interval between assessment points). The authors applied regression and cross-lagged analyses to investigate the interplay of career ambition and career success.

The results show that career ambition impacts on both extrinsic and intrinsic success. More specifically, extrinsic success was positively predicted by career orientation in Study 1. In contrast, achievement motivation was negatively related to intrinsic success (Study 1) and even diminished it over time (Study 2). Findings of the cross-lagged analysis further underlined that intrinsic success predicts extrinsic success.

The study contributes by separately investigating two aspects of career ambition and showing their different effects on career success in the specific profession of psychologists. As cross-lagged findings revealed that psychologists’ intrinsic success predicted their extrinsic success and not vice versa, the authors discuss whether psychologists might be worsening their career development in the long run by showing high achievement motivation.

Wikis have been gaining attention in the practitioner and academic literature, suggesting their use as knowledge repositories in organizational environments and even as collaborative tools for reviewing scholarly publications. And yet, little is known about factors that foster or discourage use of this technology. The purpose of this paper is to take a closer look at collaboration using wikis.

The authors look at an academic exercise using wikis in a college classroom to leverage collaboration among students. Taking elements from similar artifacts such as groupware technology, this research evaluates a model that explores the significance of perceptions of complexity and critical mass on wiki adoption.

Results show a strong acceptance of wikis among students despite not being familiar with this type of technology. Furthermore, outcomes show that students were influenced by the actions taken collectively by their peers, resulting in improved collaboration and participation.

The paper offers new insights into the subject of collaboration using wikis.

Chili pepper pods are a worldwide used and cultivated spice with a high economic and cultural importance. Bolivia is a center of origin and diversification of important crops including wild pepper varieties, but little is known about the chemical composition, antioxidant activity and the Scoville and bioactive compounds of these chili peppers. The purpose of this study was to contribute with new data about the chemical composition and the Scoville scale of Bolivian Chili peppers.

A total of 26 samples of Bolivian Chili peppers were extracted using distilled water and methanol. Total antioxidant capacity was determined by the ferric-reducing antioxidant power (FRAP) and by the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) methods. The total phenolic content was determined by Folin and Ciocalteu. Carotene, protein and ashes were determined by Bolivian analytical norms. Capsaicin was determined by high-performance liquid chromatography. All determinations were expressed as mean values± standard deviation of six replicates measured over three days of one extract. All values were less than 5% of coefficient of variation. Principal component analysis was applied to reveal patterns in the data. PC1 and PC2 together explained 78% of the total variance.

The protein content (3.8–6.3 g/100 g of dw) and the antioxidant activity (88.2 to 374 by FRAP and 87.0 to 172 evaluated by ABTS) studied in these species revealed that the values were above the average reported in the literature. The amount of pungency or capsaicin content expressed as Scoville Heat Units were reported moderately highly and very highly pungent (5,696–148,800 g dw) in several of the Bolivian peppers which demonstrates a good potential for capsaicin extraction and different applications for industry and as food ingredients.

This manuscript presents an important and novel contribution to the knowledge of the chili peppers in the region.

This article proposes a conceptual basis upon which to address strategic design as business intellectual capital.

A literature review was carried out on the subjects of strategic design and intellectual capital.

A conceptual basis is derived from the theoretical proposal that strategic design is an intangible, critical factor, which favors organizational competitiveness, when it impacts the betterment of organizational and intellectual capital processes.

On the level of business practice, this article submits a broadened view of design, which may be applied to organizational strategic processes and which transcends its emphasis in the production of goods or services.

In previous literature, strategic design has not been addressed as intellectual capital, which supports the resolution of strategic problems.

The prediction of student attrition is critical to facilitate retention mechanisms. This study aims to focus on implementing a method to predict student attrition in the upper years of a physiotherapy program.

Machine learning is a computer tool that can recognize patterns and generate predictive models. Using a quantitative research methodology, a database of 336 university students in their upper-year courses was accessed. The participant's data were collected from the Financial Academic Management and Administration System and a platform of Universidad Autónoma de Chile. Five quantitative and 11 qualitative variables were chosen, associated with university student attrition. With this database, 23 classifiers were tested based on supervised machine learning.

About 23.58% of males and 17.39% of females were among the attrition student group. The mean accuracy of the classifiers increased based on the number of variables used for the training. The best accuracy level was obtained using the “Subspace KNN” algorithm (86.3%). The classifier “RUSboosted trees” yielded the lowest number of false negatives and the higher sensitivity of the algorithms used (78%) as well as a specificity of 86%.

This predictive method identifies attrition students in the university program and could be used to improve student retention in higher grades.

The study has developed a novel predictive model of student attrition from upper-year courses, useful for unbalanced databases with a lower number of attrition students.

This article aims to describe a qualitative, exploratory study with the objective of developing scenarios for the road freight transport industry in Brazil and evaluating the effectiveness of the method applied, which used the stakeholders of said industry as a means to identify the variables of the scenarios.

According to the classification scheme developed by Huss and Honton, the authors' method fits into the intuitive logics approach to scenarios, employing concepts of stakeholder analysis as proposed by Freeman. Primary data collection was conducted through key informant interviews, as outlined by Fetterman. The use of the method of intuitive logics combined with the stakeholder analysis evaluates the consistency of experts' opinions on the characteristics of stakeholders. Four environmental scenarios, distinct but equally plausible, were generated for the road freight transport industry as it was felt that more than four scenarios tends to be too complex.

The method applied produced scenarios distinctive enough to classify them as contrasting, accounting for macroenvironmental variables and variables determined by influential stakeholders in the analyzed industry. Organized and connected, these variables produced precise end states that warrant consideration in the policies and strategies of industry players. The characteristics of the scenarios produced reveal that the method was effective. The authors found the most influential stakeholders in the industry to be the government, shipping clients, end consumers, logistics service providers, and trade associations. The industry's main uncertainties are tied to how the actions of government, shippers, and logistics service providers will unfold.

Some limitations could be identified in the method. One refers to the absence of procedures to govern the chronology of events at the time of preparation of scenario plots. Another shortcoming is the third and final stage of the research; the authors observed some weakness in the method when defining a variable that is independent because it can be independent of the variables selected for the last step but dependent on others considered but not selected.

The results of the study can stimulate reflection of stakeholders on factors that will affect their decision making, stimulate understanding of the conditions for sustainability of the industry, and identify business opportunities and necessary strategic resources for the success of organizations in the future.

The transport industry plays a vital role in factors that are paramount for the economical development of a country, such as exploration of resources and mass production, and, in Brazil, road freight transport is of particular importance. The research can guide public policy in regulating and investing in industry, since the plots facilitate the understanding of the consequences of causal relationships as well as the final states resulting from these. The scenarios reveal causal relationships strongly influenced by the stakeholder “government”, especially regarding investment in infrastructure, regulation and supervision of the industry.

Application of the method proposed by Boaventura and Fischmann to the road freight transport industry generated distinct, but equally plausible scenarios. The method considered the key uncertainties as dichotomous variables. The scenarios were different since combinations of final states of the key uncertainties led to a different logic or rationale. The authors may state that this particular application contributed towards improvement of the method, as it tested the method's logic when applied to a complex environment influenced by many stakeholders.

Curve fitting from unordered noisy point samples is needed for surface reconstruction in many applications. In the literature, several approaches have been proposed to solve this problem. However, previous works lack formal characterization of the curve fitting problem and assessment on the effect of several parameters (i.e. scalars that remain constant in the optimization problem), such as control points number (m), curve degree (b), knot vector composition (U), norm degree (k), and point sample size (r) on the optimized curve reconstruction measured by a penalty function (f). The paper aims to discuss these issues.

A numerical sensitivity analysis of the effect of m, b, k and r on f and a characterization of the fitting procedure from the mathematical viewpoint are performed. Also, the spectral (frequency) analysis of the derivative of the angle of the fitted curve with respect to u as a means to detect spurious curls and peaks is explored.

It is more effective to find optimum values for m than k or b in order to obtain good results because the topological faithfulness of the resulting curve strongly depends on m. Furthermore, when an exaggerate number of control points is used the resulting curve presents spurious curls and peaks. The authors were able to detect the presence of such spurious features with spectral analysis. Also, the authors found that the method for curve fitting is robust to significant decimation of the point sample.

The authors have addressed important voids of previous works in this field. The authors determined, among the curve fitting parameters m, b and k, which of them influenced the most the results and how. Also, the authors performed a characterization of the curve fitting problem from the optimization perspective. And finally, the authors devised a method to detect spurious features in the fitting curve.

This paper provides a methodology to select the important tuning parameters in a formal manner.

Up to the best of the knowledge, no previous work has been conducted in the formal mathematical evaluation of the sensitivity of the goodness of the curve fit with respect to different possible tuning parameters (curve degree, number of control points, norm degree, etc.).