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The aim of this research is to advance in the teaching-learning process of representing quadratic functions, both with pencil and paper and with a technological tool. For this purpose, a didactic experience is presented. Firstly, it is explained in the traditional way how to graph a quadratic function; secondly, students are introduced to the GeoGebra software. It provides a categorization of the different errors and difficulties of the students, the comparison between a graphic representation with paper and pencil and a representation with GeoGebra, and the improvement with the technological tool.

The aim of this research is to advance in the teaching-learning process of representing quadratic functions, both with pencil and paper and with a technological tool. For this purpose, a didactic experience is presented. Firstly, it is explained in the traditional way how to graph a quadratic function; secondly, students are introduced to the GeoGebra software. It provides a categorization of the different errors and difficulties of the students, the comparison between a graphic representation with paper and pencil and a representation with GeoGebra, and the improvement with the technological tool. [ABSTRACT FROM AUTHOR]

The purpose of this research was to examine the issue of job satisfaction in Mexico through psychological and sociological lenses. This research was conducted over 14 different Mexican states via the survey method. The results yielded interesting patterns. First, gender does not affect job satisfaction. Second, perceived collectivism, work flexibility, and interpersonal harmony positively influence job satisfaction in Mexico, with interpersonal harmony identified as the strongest predictor. This research found that professionals in Mexico have strong collectivism values; however, they had weakened gender differences in work settings. Implications are offered based on the findings. [ABSTRACT FROM AUTHOR]

Introduction: LigaSure™ was developed as an alternative to suture ligatures, hemoclips and staplers for ligating vessels and tissue bundles. The aim of the present study was to determine whether LigaSure can be used as a welding instrument in the performance of laparoscopic sleeve gastrectomy. Material and methods: Gastric specimens were assigned into four groups. Group 1 - specimens remained with the staple line intact. Group 2 - the staple line was oversewn. Group 3 - the staple line was resected with LigaSure. Group 4 - staple line was resected with LigaSure and the seal was oversewn. In all specimens the pressure tolerance was assessed using a portable sensor. Results: In group 1 the leak pressure was 34.7 ± 11.7 whereas in group 2 specimens the pressure increased three-fold (101.9 ± 21.4). The LigaSure seal alone (group 3) achieved a mean pressure of 13.7 mmHg. However, in group 4 there was an exponential increase on their burst strength up to 142 mmHg ( p = 0.0005). Conclusion: According to our results, LigaSure could be used to perform laparoscopic sleeve gastrectomy with reduction of staple-line bleeding and, when reinforced with a running suture, it achieves a strength that approaches that of staples plus oversewing. [ABSTRACT FROM AUTHOR]

Purpose -- The purpose of this paper is to investigate the relationships between the magnitude of job offshoring and organizational contingencies, including total number of employees, multinationality, business diversification, and relevancy of business activities. Design/methodology/approach -- Previous studies on job offshoring were restricted in descriptive and prescriptive understanding of the phenomena. Utilizing secondary data, this paper provides empirical findings on the magnitude of job offshoring from an organizational contingency perspective. Findings -- The results indicate that larger and multinational firms tend to offshore a larger number of jobs, and less diversified firms tend to offshore a higher ratio of jobs. Also, firms that offshore their core business activities are more likely to move a higher ratio of jobs to offshore destinations. Research limitations/implications -- This paper reveals some of the key organizational factors that account for the magnitude of job offshoring within American firms. Practical implications -- The findings offer insights in what the government, the society, the workforce need to prepare for future changes and the globalization of business. Originality/value -- The paper offers empirical explanations of the magnitude of job offshoring. Various governmental, private, and international institutions may rely on the findings in making political, commercial, and social policies and decisions. [ABSTRACT FROM AUTHOR]

Increased gas adsorption in a series of post-synthetically modified metal-organic frameworks (MOFs) of the type HKUST-1 was achieved by the partial cation exchange process. Manipulation of post-synthetic conditions demonstrates high tunability in the site substitution and gas adsorption properties during the dynamic equilibrium process. In this work, post-synthetic modification of Cu 3 (BTC) 2 is carried on by exposure to TM 2+ solutions (TM = Mn, Fe, Co, Ni) at different time intervals. The crystal structure, composition, and morphology were studied by powder X-ray diffraction, Fourier-transform infrared spectroscopy, inductively coupled plasma optical emission spectroscopy, and scanning electron microscopy. Structural analysis supports the retention of the crystal structure and partial substitution of the Cu metal nodes within the framework. A linear increase in the transmetalation process is observed with Fe and Co with a maximum percentage of 39 and 18%, respectively. Conversely, relatively low cation exchange is observed with Mn having a maximum percentage of 2.40% and Ni with only 2.02%. Gas adsorption measurements and surface area analysis were determined for each species. Interestingly, (Cu/Mn) 3 (BTC) 2 revealed the highest CO 2 adsorption capacity of 5.47 mmol/g, compared to 3.08 mmol/g for Cu 3 (BTC) 2 . The overall increased gas adsorption can be attributed to the formation of defects in the crystal structure during the cation exchange process. These results demonstrate the outstanding potential of post-synthetic ion exchange as a general approach to fine-tuning the physical properties of existing MOF architectures.