Search results for "41"
showing 10 items of 3365 documents
Engaging Mathematical Reasoning-and-Proving: A Task, a Method, and a Taxonomy
2019
This article is the second paper in a series of papers on studies focusing on teaching mathematical reasoning-and-proving in elementary mathematics classroom. Participants are in-service teachers enrolled in a continuing university education program in mathematics. Results from the first paper suggested the method of imaginary dialogues to have the potential to support in-service teachers in engaging their students in mathematical reasoning-and-proving, and Balacheff’s taxonomy of proofs to support in-service teachers in identifying students’ argumentation. This study is on the following years’ in-service teachers in the program. It examines their perceptions of the usefulness of two consti…
The teacher of physical education in primary textbooks
2019
El objetivo del presente estudio es analizar cómo se representa a la maestra de educación física en los libros de texto de esta área, en la etapa de Educación Primaria. Se realiza un estudio cuantitativo que muestra un número elevado de maestras con respecto al maestro de educación física, principalmente en el primer ciclo de Primaria y otro cualitativo, a través del análisis de contenido, identificando un tratamiento estereotipado en cuanto a las características físicas de la docente, al representar a una maestra eminentemente joven, de raza blanca, delgada, con ropa deportiva y sin discapacidad. Pero a la vez, aparece un tratamiento más abierto y participativo en cuanto al rol representad…
Constructing Large 2D Lattices Out of DNA-Tiles.
2021
The predictable nature of deoxyribonucleic acid (DNA) interactions enables assembly of DNA into almost any arbitrary shape with programmable features of nanometer precision. The recent progress of DNA nanotechnology has allowed production of an even wider gamut of possible shapes with high-yield and error-free assembly processes. Most of these structures are, however, limited in size to a nanometer scale. To overcome this limitation, a plethora of studies has been carried out to form larger structures using DNA assemblies as building blocks or tiles. Therefore, DNA tiles have become one of the most widely used building blocks for engineering large, intricate structures with nanometer precis…
History of Sciences and Museology (Scientific Papers University of Latvia, vol. 800)
2014
An adaptive approach to learning the preferences of users in a social network using weak estimators
2012
Published version of an article in the journal: Journal of Information Processing Systems. Also available from the publisher at: http://dx.doi.org/10.3745/JIPS.2012.8.2.191 - Open Access Since a social network by definition is so diverse, the problem of estimating the preferences of its users is becoming increasingly essential for personalized applications, which range from service recommender systems to the targeted advertising of services. However, unlike traditional estimation problems where the underlying target distribution is stationary; estimating a user's interests typically involves non-stationary distributions. The consequent time varying nature of the distribution to be tracked i…
Anti-Proliferative Activity of A Hydrophilic Extract of Manna from Fraxinus angustifolia Vahl through Mitochondrial Pathway-Mediated Apoptosis and Ce…
2020
Manna is produced from the spontaneous solidification of the sap of some Fraxinus species, and, owing its content in mannitol, is used in medicine as a mild laxative. Manna is also a rich source of characteristic bio-phenols with reducing, antioxidant and anti-inflammatory properties. This study assesses the activity of a hydrophilic extract of manna (HME) on cellular and molecular events in human colon-rectal cancer cells. HME showed a time- and concentration-dependent anti-proliferative activity, measured by MTT assay, in all the cell lines examined, namely Caco-2, HCT-116 and HT-29. The amounts of HME that caused 50% of cell death after a 24 h treatment were 8.51 ±
Induction of Apoptosis, Autophagy and Ferroptosis by Thymus vulgaris and Arctium lappa Extract in Leukemia and Multiple Myeloma Cell Lines
2020
Thymus vulgaris and Arctium lappa have been used as a folk remedy in the Iraqi Kurdistan region to deal with different health problems. The aim of the current study is to investigate the cytotoxicity of T. vulgaris and A. lappa in leukemia and multiple myeloma (MM) cell lines and determine the mode of cell death triggered by the most potent cytotoxic fractions of both plants in MM. Resazurin assay was used to evaluate cytotoxic and ferroptosis activity, apoptosis, and modulation in the cell cycle phase were investigated via Annexin V-FITC/PI dual stain and cell-cycle arrest assays. Furthermore, we used western blotting assay for the determination of autophagy cell death. n-Hexane, chlorofor…
Silymarin and Cancer: A Dual Strategy in Both in Chemoprevention and Chemosensitivity
2020
Silymarin extracted from milk thistle consisting of flavonolignan silybin has shown chemopreventive and chemosensitizing activity against various cancers. The present review summarizes the current knowledge on the potential targets of silymarin against various cancers. Silymarin may play on the system of xenobiotics, metabolizing enzymes (phase I and phase II) to protect normal cells against various toxic molecules or to protect against deleterious effects of chemotherapeutic agents on normal cells. Furthermore, silymarin and its main bioactive compounds inhibit organic anion transporters (OAT) and ATP-binding cassettes (ABC) transporters, thus contributing to counteracting potential chemor…
Lifetime total and beverage specific - alcohol intake and prostate cancer risk: a case-control study
2004
Abstract Background We investigated lifetime alcohol consumption and prostate cancer risk in a case-control study conducted in Buffalo, NY (1998–2001). Methods The study included 88 men, aged 45 to 85 years with incident, histologically-confirmed prostate cancer and 272 controls. We conducted extensive in-person interviews regarding lifetime alcohol consumption and other epidemiologic data. Results Prostate cancer risk was not associated with lifetime intake of total and beverage specific ethanol. In addition we found no association with number of drinks per day (average drinks per day over the lifetime) or drinks per drinking day (average drinks per day on drinking days only over the lifet…
Synthesis of C3/C1-Substituted Tetrahydroisoquinolines
2015
A broad biological screening of the natural alkaloid N-methylisosalsoline (2) extracted from Hammada scoparia leaves against a panel of human and parasitic proteases revealed an interesting activity profile of 2 towards human 20S proteasome. This outcome suggests that the 1,2,3,4-tetrahydroisoquinoline skeleton may be exploited as a template for the development of novel anticancer agents. In this article, we report the synthesis and chemical characterization of a new series of isosalsoline-type alkaloids (10-11) with variations at N2 and C3 positions with respect to the natural Compound 2, obtained by a synthetic strategy that involves the Bischler-Napieralski cyclization. The substrate for…