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Background: Well-developed assessment methods have a positive impact on students’ performance, and higher education institutes are usually encouraged to establish and use effective assessment methods that effectively enhance the learning process. Objectives: This study was designed to compare students’ performance in multiple choice questions (MCQs) including best single answer (BSA) and multiple true and false (MTF) types, and very short answer (VSA) questions, and to evaluate gender differences and feedback from students and faculty. Materials and methods: A test containing three different types of questions, BSA, MTF and VSA questions (10 each), was delivered to eight groups of veterinary pathology students (3rd level, Faculty of Veterinary Medicine, Assiut University, Assiut, Egypt) in April 2022. Students’ performance, test reliability and gender differences as well as feedback from students and faculty were evaluated. Results: Students did a significant higher performance in BSA and MTF questions compared to VSA questions. The reliability of BSA, MTF and VSA questions between different groups of students were 0.53, 0.52 and 0.13, respectively. Girl students achieved a higher performance in the whole test compared to boy students. Both boy and girl students showed nearly similar performance in BSA and MTF questions. However, girl students got significant higher score in VSA questions compared to boy students. Students’ and faculty opinions were in favor of BSA and MTF questions. Conclusion: Students did much better in MCQs than VSA questions. BSA and MTF questions are preferentially favored by students and faculty.

Introducción. El cianoacrilato de n-butilo (BCA) y su polímero, el policianoacrilato de n-buti- lo (PBCA) poseen excelentes propiedades adhesivas, biocompatibles y biodegradables para aplicaciones médicas. Este trabajo presenta nuevos métodos para producir BCA de alta pu- reza y micro/nanofibras de PBCA como potenciales productos farmacéuticos. Métodos. La radiación de microondas se utilizó para producir BCA y la técnica de electro-hilado para las micro/nanofibras de PBCA, cuyas propiedades química-físicas, mecánicas, biológicas y de transportación de fármacos fueron evaluadas. Resultados. El tiempo del proceso para la producción del BCA se redujo de 3 veces a 5 veces al emplear la radiación de microondas respecto al baño de aceite. El electro-hilado a disoluciones de PBCA con distintas masas moleculares produjo fibras libres de defectos con diámetros de 400 nm a 5 mm. Se deter- minaron valores del módulo de Young y de tensión máxima de 0,7 MPa a 1,9 MPa y de 0,05 MPa a 0,12 MPa respectivamente. La degradación térmica de las nanofibras de PBCA y las cargadas con 15 % de 5-fluorouracilo ocurrió de 110 oC a 241 oC y de 100 oC a 309 oC con sus respectivos máximos en 186 oC y 203 oC. El citostático 5-fluorouracilo se distribuyó homogéneamente en las fibras de PBCA, liberándose el 20 % en 7 días y el resto de forma gradual (hasta 96 días) en medio fisiológico. Los fibroblastos humanos proliferaron sobre las nanofibras de PBCA. Como conclusiones, la radiación de microondas reduce significativa- mente el tiempo de síntesis del BCA. El electro-hilado del PBCA produce mallas constituidas por micro/nanofibras, que pudieran utilizarse como sistemas transportadores de fármacos y para ingeniería de tejidos.

La estructura del texto está dividida en tres partes: en la primera se presentan los aspectos referidos al contexto internacional y se focaliza en la temática de la gobernanza, el Estado y la sociedad civil. En la segunda se consideran las organizaciones no gubernamentales (ONG) a fin de dilucidar la complejidad que se esconde detrás de la noción de gobernanza. Finalmente, la tercera parte contiene algunas preguntas y conclusiones. Abstract The presentation is divided into three parts; in the first part, aspects referred to international context are addressed, focusing on Governance, State and Civil Society. The second part deals with Non Governmental Organizations (NGO) and seeks to dilucidate the complexity which lies beyond the concept of governance. Finally, the third part includes some questions and conclusions.

Extensions and modifications of standard electrochemical techniques, accounting for unique conditions related to biological considerations, have proved useful in attacking some problems related to biocompatibility of the Biomaterial. Some authors have demonstrated that modern electrochemical techniques can be used to clarify some difficult problems in the field of biomaterials. Precious alloys can not be apply for all cases especially such as long range bridges or prosthesis. For this reason, Ni-Cr as well as Co-Cr casting alloys have been used for dental application as alternatives to precious alloys. The biocompatibility of Ni-Cr alloys have been questioned because of their corrosive, allergenic, and even mutagenic potentials. The nature of passive films on metals and alloys is the ultimate factor which controls their corrosion behavior. There is little reliable information on the effects of the physical and chemical factors involved in the tissue response to an implant and the associated ionic release on the cell-material interaction. Depending on the casting process during the production of a dental prosthesis, these alloys may show different phases, ones may be more stable than other. For this reason, the development of a fast and simple method for determination of the corrosion behavior as a control test in the production of a metallic dental devices is of great interest. The purpose of this work was to present some results on the corrosion behavior of two different commercial alloys: Wiron 99 (Ni-Cr alloy) and Aurolloyd kf (Au alloy). These results were obtained by several electrochemical methods: open circuit potential-time and liner sweep voltammetry for Wiron 99, and open circuit potential-time and cyclic voltammetry for Aurolloyd kf.