Vibrations of an Inhomogeneous Layer

In this study, we have investigated vibrations of an inhomogeneous layer which is forced along its bottom. The shear modulus of the layer varies with depth. Considering the layer thickness is constant and the forcing displacement at the bottom is horizontal, shear vibrations will be studied. The solution of the governing equation has been carried out by using Bessel functions including unknown parameter q. Frequencies which make the amplitude of vibrations infinite are called natural frequencies of the layer. Variational of the natural frequencies and the shape of the shearing waves along the thickness of the layer have been investigated for some values of inhomogeneity parameters

Evaluating the quality of the ontology-based auto-generated questions

An ontology is a knowledge representation structure which has been used in Virtual Learning Environments (VLEs) to describe educational courses by capturing the concepts and the relationships between them. Several ontology-based question generators used ontologies to auto-generate questions, which aimed to assess students' at different levels in Bloom's taxonomy. However, the evaluation of the questions was confined to measuring the qualitative satisfaction of domain experts and students. None of the question generators tested the questions on students and analysed the quality of the auto-generated questions by examining the question's difficulty, and the question's ability to discriminate between high ability and low ability students. The lack of quantitative analysis resulted in having no evidence on the quality of questions, and how the quality is a�affected by the ontology-based generation strategies, and the level of question in Bloom's taxonomy (determined by the question's stem templates). This paper presents an experiment carried out to address the drawbacks mentioned above by achieving two objectives. First, it assesses the auto-generated questions' difficulty, discrimination, and reliability using two statistical methods: Classical Test Theory (CTT) and Item Response Theory (IRT). Second, it studies the effect of the ontology-based generation strategies and the level of the questions in Bloom's taxonomy on the quality of the questions. This will provide guidance for developers and researchers working in the field of ontology-based question generators, and help building a prediction model using machine learning techniques

Anti-cancer drug validation: the contribution of tissue engineered models

Abstract Drug toxicity frequently goes concealed until clinical trials stage, which is the most challenging, dangerous and expensive stage of drug development. Both the cultures of cancer cells in traditional 2D assays and animal studies have limitations that cannot ever be unraveled by improvements in drug-testing protocols. A new generation of bioengineered tumors is now emerging in response to these limitations, with potential to transform drug screening by providing predictive models of tumors within their tissue context, for studies of drug safety and efficacy. Considering the NCI60, a panel of 60 cancer cell lines representative of 9 different cancer types: leukemia, lung, colorectal, central nervous system (CNS), melanoma, ovarian, renal, prostate and breast, we propose to review current Bstate of art^ on the 9 cancer types specifically addressing the 3D tissue models that have been developed and used in drug discovery processes as an alternative to complement their studyThis article is a result of the project FROnTHERA (NORTE-01-0145-FEDER-000023), supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). This article was also supported by the EU Framework Programme for Research and Innovation HORIZON 2020 (H2020) under grant agreement n° 668983 — FoReCaST. FCT distinction attributed to Joaquim M. Oliveira (IF/00423/2012) and Vitor M. Correlo (IF/01214/2014) under the Investigator FCT program is also greatly acknowledged.info:eu-repo/semantics/publishedVersio

Red blood cell enzyme biochemical polymorphism in Anatolian shepherd dog

Anatolian shepherd dog (Asd), probably the descendants of the large hunting dogs of Mesopotamia, has been the most preferred dog in Anatolia as a guard dog of flocks. Furthermore, because of their high endurance of extreme of heat and cold, recently they started to be employed in African countries and in Australia. To help the conservation and management strategies to be establihed for this highly valuable gene pool, genotypes of 108 Asd individuals, belonging to four breeding farms and to local people in a region from Central Anatolia (altogether five populations), were determined by using horizontal starch gel electrophoresis based on ESD, PGD, CAI, GOT and SOD enzyme systems. Bands observed on starch gels for Asd were compared with those obtained from 21 other individuals belonging to 7 other well-known breeds

Lithium for treatment and chemo-sensitization: Testing the hypothesis on SH-SY5Y cells in monolaver and 3D-spheroids

1st International Conference on Nitric Oxide and Cancer -- NOV 26-28, 2007 -- Paris, FRANCEWOS: 00025083600006