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This book focuses on English as a Foreign Language (EFL) and provides advice on how to approach EFL teaching in the online context. Coronavirus has accelerated e-learning significantly and has highlighted the need of appropriate web tools that will allow teachers to present their material either synchronously or asynchronously, while also adequately assess their students. At the same time, there is a need of tools that can engage the students and motivate them to actively participate in the lesson. With e-learning being a rather new challenge for both teachers and students, this book provides research- and practice- based chapters with strategies, techniques, approaches, and methods which have proven to be successful in e-learning environments, maximizing their impact. Apart from presenting research results with strong pedagogical implications on online or blended English language learning and teaching, the book also trains educators on utilizing online tools and managing online learning environments and platforms.

A vital inquiry into trans issues in education, this compelling work argues for the design of education research, policies, and environments that honor all gender experiences and identities. Edited by two prominent figures in trans studies, Mario I. Suárez and Melinda M. Mangin, "Trans Studies in K-12 Education" brings together scholars and professionals representing a range of academic traditions, research methodologies, and career backgrounds to explore why and how schools should affirm gender diversity and challenge gender-based inequities. The collection offers a comprehensive examination of how gender is manifested in the educational context. Gathering a wealth of evidence, the book's contributors expose the prevailing norm of gendered environments, which are entrenched in the very design and execution of educational research. The collection also lays out a critical overview of US laws and policies related to gender equity, gender identity, and gender expression and how these frameworks impact educational environments. These findings draw attention to deficit-oriented, pathologizing ideologies that surround nonconforming gender identities and the detrimental, often traumatizing effects on transgender students and educators. Throughout, the contributors recommend methods for establishing gender-affirming research, policy, and practice. They outline the sociopolitical and legal pathways that trans and nonbinary students and school employees may use to secure education and workplace rights. They discuss the positive gains made by professional development for teachers, LGBTQ+ advocacy, and community programs that successfully support transgender and gender-nonconforming individuals. Ultimately, the volume highlights the promise of creating K-12 education spaces that are liberating rather than constraining.

This groundbreaking volume is the first to concentrate specifically on the experiences, challenges, and triumphs of immigrant-origin community college students. Drawing on data from the Research on Immigrants in Community College Study (RICC), chapters highlight the unique needs of these students, the role of classrooms and campus settings, out-of-class time spent on campus, the importance of relationships, expectations versus outcomes, and key recommendations for policy and practice. The text integrates an array of important topics, including developmental challenges, language learning, the undocumented student experience, microaggressions, counseling center use, and academic engagement. Above all, this book looks at what community colleges can do to better help this growing population of new Americans succeed. Book features: (1) holistic and resilience-based strategies of practice that build on the many strengths of new Americans in higher education; (2) federal, state, and local administrative policy recommendations to help this important and growing student population flourish; (3) an in-depth study of more than 600 diverse immigrant-origin students attending three community colleges in New York City; and (4) inter-disciplinary, mixed-method research (survey, interviews, classroom observations) from a variety of viewpoints (students, faculty, administrators). This book contains the following chapters: (1) Introduction: What Are the Opportunities, Challenges, and Experiences of Immigrant-Origin Students in Community Colleges? (Carola Suárez-Orozco, Olivia Osei-Twumasi, Robert Teranishi, and Marcelo Suárez-Orozco); (2) Unsigned (Dalal Katsiaficas); (3) The Pathways of English Learners in Community Colleges: Persistence and Push-Out (Tasha Darbes); (4) Resilience in the Face of Adversity: Undocumented Students in Community College (Olivia Osei-Twumasi and Guadalupe Lopez-Hernandez); (5) Classroom Engagement in Community Colleges: Moving Beyond Student and Instructor Dimensions to a Dynamic Settings Approach (Stacey Alicea and Carola Suárez-Orozco); (6) The Prevalence and Relevance of Microaggressions in Community College Classrooms (Carola Suarez-Orozco, Dalal Katsiaficas, Saskias Casanova, Margary Martin, and Sukhmani Singh); (7) The Use of Out-of-Class Time on Campus of Immigrant-Origin Students (Olivia Osei-Twumasi, Carola Suarez-Orozco, Edwin Hernandez, Monique Corral, and Janet Cerda); (8) Immigrant-Origin Community College Students' Help-Seeking Orientation and Use of Counseling Services (Sandra I. Dias); (9) Immigrant-Origin Community College Students' Experiences with Faculty: Relational Empowerment or Relational Helplessness? (Carola Suarez-Orozco, Natacha Cesar-Davis, and Alfredo Novoa); (10) Through a Lens of Deficit: Faculty and Administrator Perceptions of Immigrant-Origin Students (Heather Herrera, Margary Martin, and Natacha Cesar-Davis); (11) The Significance of Networks of Relationships for Immigrant-Origin Students (Stacey Alicea); (12) The Role of Instructor Relationships in Predicting Academic Outcomes Among Immigrant-Origin Community College Students (McKenna Parnes, Sarah Schwarz, Carola Suarez-Orozco, and Olivia Osei-Twumasi); (13) Dreams Versus Realities: Graduation Rates of Immigrant-Origin Community College Students (Olivia Osei-Twumasi and Juliana Karras Jean-Gilles); and (14) Implications for the Educational Intervention & Policy (Robert Teranishi, Cecilia Rios-Aguilar, and Cynthia Alcantar). [Foreword by James A. Banks.]

Mass migration and globalization are creating new and deep challenges to education systems the world over. In this volume, some of the world's leading researchers in multicultural education and immigration discuss critical issues related to cultural sustainability, structural inclusion, and social cohesion. The authors consider how global migration is forcing nationstates to reexamine and reinvent the ways in which they socialize and educate diverse groups for citizenship and civic engagement. These chapters also address how schools can help migrant and immigrant groups attain the knowledge, values, and skills required to become fully participating citizens, while retaining important aspects of their home, community, languages, and culture. Case studies from the United States and Israel are used to illustrate how these concepts are manifested in two immigrant nations. Book features include: (1) An examination of the theories, empirical findings, and promising practices related to education for citizenship; (2) Descriptions of large-scale migration and its influences on curricula, modes of teaching, and civic education; (3) An interdisciplinary overview of the issues facing immigrant children in schools by Carola SuárezOrozco and Amy K. Marks; (4) Implications for reforming schools in ways that will help students from diverse racial, ethnic, cultural, and linguistic groups become effective citizens; (5) A comprehensive chapter on second language learning by Guadalupe Valdés, a leading expert; and (6) Recommendations for preparing teachers to meet the needs of diverse student populations. [Contributors include: Tali Aderet-German, Ayman K. Agbaria, James A. Banks, Zvi Bekerman, Miriam Ben-Peretz, Amy K. Marks, Minas Michikyan, John P. Myers, Sonia Nieto, Carola Suárez-Orozco, Marcelo M. Suárez-Orozco, Guadalupe Valdés, and Gregory White.]

The article discusses the institutionalization of equal opportunities in Europe. The unequal development of institutionalization, the overlapping of institutionalization in each country's entry into the European Union (EU), and the consequent importance of the EU for driving equal opportunities agenda, are being emphasized. Moreover, a discussion of the difference in equality discourses which shaped the European thinking is also discussed.

The article presents an insight into the cultural psychology of Hispanic immigrants and their children. It tries to explore important aspects of the Hispanic American immigrant experience considering first and second generation individual, family and group dynamics. Hispanics come from many different countries and different socio-economic, educational and professional backgrounds. Hence many immigrants in a new land experience losses, some marginality and deprivation but know that they are making a tremendous difference in the lives of those left behind. Ongoing discrimination and ethnic tension has an erosive effect particularly in the more vulnerable children of immigrants.

Variations in habitat quality impact on breeding success, leading to strong selection pressure for the best sites to be occupied first during a population increase and last during a decline. Coupled with dispersal and metapopulation processes, the result is that snapshot surveys of wildlife distributions may fail to reveal core areas that conservation seeks to protect. At a local scale, territory occupancy is a good indicator of quality but data are not readily available to assess occupancy for rarer species, in remote areas, and over large spatial extents. We introduce temporal suitability analysis as a way to generate an analogue of occupancy from a single survey and illustrate it using data on the little bustard in Spain. We first used Generalised Additive Modelling (GAM) to build a predictive distribution model using Geographic Information System (GIS) coverages and satellite imagery, and then applied the model retrospectively to a time series of satellite images to produce one distribution map for each year. These annual maps differed in the extent of Spain predicted as suitable for little bustards. By overlaying the maps, we identified areas predicted as suitable in one to n years. We show that this temporal suitability map correlates with a conventional habitat suitability map based on a single year but contains extra information on hierarchical use of habitats and the lag between suitability and use. The technique may be applied at a variety of spatial scales to reveal changes in expected occupancy as land use or external factors determining land cover types vary over time. [ABSTRACT FROM AUTHOR]

We have examined the distribution of 26 species of steppe birds in the Iberian Peninsula and the Balearic Islands within a grid of 5,070 10 × 10 km grid cells. The most valuable areas for steppe birds have been identified by selecting the upper 5% of the 10 × 10 km grid cells after a simple ranking based on the following criteria: species-richness, richness of rare species, rarity index, species vulnerability at Spanish, European and Global levels, and using an index combining the previous criteria. We have also used a heuristic algorithm to select those areas which offered most complementarity. The results have been analysed on a national scale and have been compared with those obtained by species assessments in previous status summaries. Finally, we have performed an analysis of the coverage afforded to locations which are valuable for steppe species by Natural Protected Areas (NPAs) and Special Protected Areas (SPAs), and an evaluation of the potential effects of temporal changes in species' threat-status. The combined index was the most reliable criterion for defining hotspots, encompassing 15% of the species' distributions within 5% of the total area considered. This index showed a high level of geographical concordance with the other criteria (nearly 70% of the selected grid cells coincided). Analysis of complementarity delivered poorer results than simple rank-scoring. The analysis of the efficiency of NPA network showed a very low coverage (less than 2%) of the hotspots selected according to the Combined Index. Coverage of the SPA network was higher (nearly 45%), although it diminished (to <35%) when only steppe-defined SPAs were included. The geographical concordance between high-value areas selected using current status summaries and those chosen using earlier ones was low for European threat status (53.4%), intermediate (63.2%) for Spanish threat status and high for SPEC status (78.1%). The Combined Index showed a high level of geographical concordance between the old and new data (76.6%). We conclude that automatic scoring methods (identifying hotspots) are useful for selecting valuable areas and for analysing the efficiency of the network of protected natural spaces, as well as for examining the potential effects of status changes on hotspot definition. Furthermore, the Spanish SPA network does not cover the most important areas for steppe birds adequately. [ABSTRACT FROM AUTHOR]

Programmed cell death (PCD) is an integral part of embryogenesis. In plant embryos, PCD functions during terminal differentiation and elimination of the temporary organ, suspensor, as well as during establishment of provascular system. Embryo abortion is another example of embryonic PCD activated at pathological situations and in polyembryonic seeds. Recent studies identified the sequence of cytological events leading to cellular self-destruction in plant embryos. As in most if not all the developmental cell deaths in plants, embryonic PCD is hallmarked by autophagic degradation of the cytoplasm and nuclear disassembly that includes breakdown of the nuclear envelope and DNA fragmentation. The optimized setup of terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) allows the routine in situ analysis of nuclear DNA fragmentation in plant embryos. This chapter provides step-by-step procedure of how to process embryos for TUNEL and how to combine TUNEL with immunolocalization of the protein of interest. [ABSTRACT FROM AUTHOR]

Plant embryogenesis requires a tight balance between cell proliferation and differentiation. In animals, embryogenesis is dependent on cell migrations, which is in contrast to plant embryogenesis where the rigid cell wall precludes migration. Therefore, plants have to position cells correctly by defining the direction of the division plane during proliferation and control cell shape by local cell expansion. Both these processes are reliant on the organization and dynamics of the cytoskeleton - actin filaments and microtubules. In previous work (7), we have shown that differentiation of the embryo suspensor is accompanied by reorientation of microtubules from random to transverse and reorganization of actin filaments from a fine filamentous network to bundled longitudinal cables. Here, we describe the technique for visualization of cytoskeletal components including actin filaments, microtubules and their associated proteins during the development of plant embryos in whole-mount specimens. [ABSTRACT FROM AUTHOR]

Plasmodesmata provide routes for communication and nutrient transfer between plant cells by interconnecting the cytoplasm of adjacent cells. A simple fluorescent tracer-loading assay was developed to monitor patterns of cell to cell transport via plasmodesmata specifically during embryogenesis. A developmental transition in plasmodesmatal size exclusion limit was found to occur at the torpedo stage of embryogenesis in Arabidopsis; at this time, plasmodesmata are downregulated, allowing transport of small (∼0.5 kDa) but not large (∼10 kDa) tracers. This assay system was used to screen for embryo defective mutants, designated increased size exclusion limit of plasmodesmata that maintain dilated plasmodesmata at the torpedo stage. [ABSTRACT FROM AUTHOR]

Embryogenesis in Arabidopsis thaliana depends on the proper establishment and maintenance of local auxin accumulation. In the course of elucidating the connections between developmental progress and auxin distribution, several techniques have been developed to investigate spatial and temporal distribution of auxin response or accumulation in Arabidopsis embryos. This chapter reviews and describes two independent methods, the detection of the activity of auxin responsive transgenes and immunolocalization of auxin itself. [ABSTRACT FROM AUTHOR]

Promoter trapping is a particular gene trap strategy that represents a valuable tool for the discovery of specific cell-type markers. The principle is to generate a collection of transgenic lines with random insertions of a promoter-less reporter gene and to screen for specific reporter activity in the domain of interest. The use of β-glucuronidase (GUS) as a reporter gene provides a simple and sensitive assay that allows identification of very restricted expression patterns and makes the promoter trap appropriate to study embryogenesis. Plant embryogenesis starts at the fertilization of the egg cell encapsulated in the maternal tissue and leads to the establishment of a new organism capable of an autonomous life. Uncovering genes specifically expressed in sub-domain of the embryo during its development represents a major technical challenge due, in part, to size and accessibility limitations. Promoter trapping approaches have been successfully used to overcome these problems. The trapped activity represents thereafter a useful genetic marker of the uncovered cell type, which is expected to reveal the properties of a specific promoter shedding light on a new gene function. In this chapter, protocols for examining and documenting GUS reporter gene activities in the embryo are described. Methods for the amplification of sequences flanking insertions and subsequent molecular and genetic characterization are provided. [ABSTRACT FROM AUTHOR]

A key objective in the study of plant embryogenesis is to identify genes expressed in temporal and spatial patterns during development, in order to understand transcriptional control mechanisms regulating pattern formation, differentiation and morphogenesis. Mutagenic approaches have proved powerful to identify essential genes, but global, transcriptome-wide analysis of mRNA profiles in cells at different stages of differentiation would allow the identification of changes in the abundance of major classes of transcripts expressed from genes that are known to respond to regulatory signals, such as hormones. Particular classes of transcription factors or other genes might also be discovered to be associated with particular aspects of cell differentiation. This information would allow the construction of models to describe how signalling pathways might modulate transcriptional changes associated with cell differentiation. Previous limitations in tissue accessibility for RNA isolation have been overcome through the use of laser-capture microdissection, which allows cells from different embryonic tissues to be isolated, for RNA isolation, amplification and analysis by either polymerase chain reaction or DNA microarray techniques. [ABSTRACT FROM AUTHOR]

To perform an effective genetic screen for embryo-specific mutants is a prerequisite for understanding the molecular mechanisms that control Arabidopsis embryo development. Mutagenesis based on either T-DNA or transposon insertion has been successfully used in identifying embryonic mutants. We present here a typical genetic screen for putative embryonic mutants based on distorted Mendelian segregation ratio (2:1) and reduced seed set. It is advisable to examine whether the mutation also affects gametophytic functions by performing reciprocal crosses between wild type and the mutant. We also provide detailed explanations on the whole-mount clearing method, a simple but effective method for phenotypic analysis of mutant embryos blocked in certain steps during the process necessary for embryo viability and development. [ABSTRACT FROM AUTHOR]

Barley microspore embryogenesis represents an attractive system to study stress-induced cell differentiation and is a valuable tool for efficient plant breeding. In contrast to zygotic embryogenesis, all developmental stages are freely accessible at a large scale for observation, molecular analysis and manipulation techniques. In barley, there is a high percentage of microspores that become embryogenic after stress treatment in a mannitol solution. These microspores have the capacity to follow an embryogenic route in both liquid and solid cultures, yielding up to 10% of embryos. In this protocol, we describe three different culture systems for obtaining barley microspore-derived embryos, where embryos develop in liquid medium, on top of a solid medium layer or immobilized in a thin layer of agarose. While liquid culture systems allow the generation of large amounts of embryos for molecular analysis, solid culture systems are the ultimate tool for probing embryo development. [ABSTRACT FROM AUTHOR]

Embryogenesis of Arabidopsis thaliana follows a nearly invariant cell division pattern and provides an ideal system for studies of early plant development. However, experimental manipulation with embryogenesis is difficult, as the embryo develops deeply inside maternal tissues. Here, we present a method to culture zygotic Arabidopsis embryos in vitro. It enables culturing for prolonged periods of time from the first developmental stages on. The technique omits excision of the embryo by culturing the entire ovule, which facilitates the manual procedure. It allows pharmacological manipulation of embryo development and does not interfere with standard techniques for localizing gene expression and protein localization in the cultivated embryos. [ABSTRACT FROM AUTHOR]

Methods have been developed to isolate gametes of higher plants and to fertilize them in vitro. Zygotes, embryos, fertile plants and endosperm can now be obtained from in vitro fusion of pairs of sperm and egg cells and of pairs of sperm and central cells, respectively. This allows examination of the earliest developmental processes precisely timed after fertilization. The isolated egg and central cell, fertilized and cultured in vitro, are able to self-organize apart from each other and without mother tissue in the typically manner. Thus, this system is a powerful and unique model for studies of early zygotic embryogenesis and endosperm development. The underlying processes are now comparatively studied in detail by investigations of expression of genes and their corresponding proteins. The use of these techniques opens new avenues in fundamental and applied research in the areas of developmental and reproductive plant biology. [ABSTRACT FROM AUTHOR]

Somatic embryogenesis, the process in which embryos, similar in morphology to their zygotic counterparts, are induced to develop in culture from somatic cells, is a suitable model system for investigating the regulation of embryo development. Through this process, a large number of embryos at defined stages of development can easily be obtained. Somatic embryogenesis in Norway spruce is comprised of a sequence of steps including initiation, proliferation, early embryo formation, embryo maturation, desiccation and germination. To execute this pathway, a number of critical physical and chemical treatments should be applied with proper timing. Embryogenic cell lines of Norway spruce are initiated from zygotic embryos. The cell lines proliferate as proembryogenic masses (PEMs) in the presence of auxin and cytokinin. Early somatic embryos develop from PEMs after withdrawal of auxin and cytokinin. PEM to somatic embryo transition is a key developmental switch that determines the yield and quality of mature somatic embryos. The embryos develop further, to a stage corresponding to late embryogeny, in the presence of abscisic acid. Some cell lines deviate from normal pattern formation exhibiting developmental arrest at certain stages. These arrested cell lines, together with transgenic lines, are valuable tools for studying embryo development. Particle bombardment is routinely used to produce transgenic plants of Norway spruce. [ABSTRACT FROM AUTHOR]

Plant embryo development is a complex process that includes several coordinated events. Maize mature embryos consist of a well-differentiated embryonic axis surrounded by a single massive cotyledon called scutellum. Mature embryo axis also includes lateral roots and several developed leaves. In contrast to Arabidopsis, in which the orientation of cell divisions are perfectly established, only the first planes of cell division are predictable in maize embryos. These distinctive characteristics joined to the availability of a large collection of embryo mutants, well-developed molecular biology and tissue culture tools, an established genetics and its economical importance make maize a good model plant for grass embryogenesis. Here, we describe basic concepts and techniques necessary for studying maize embryo development: how to grow maize in greenhouses and basic techniques for in vitro embryo culture, somatic embryogenesis and in situbreak hibridization. [ABSTRACT FROM AUTHOR]

Embryogenesis in higher plants consists of two major phases, morphogenesis and maturation. Morphogenesis involves the establishment of the embryo's body plan, whereas maturation involves cell expansion and accumulation of storage macromolecules to prepare for desiccation, germination and early seedling growth. Arabidopsis mutants showing defects in embryogenesis have provided information for understanding the events that govern embryo formation through molecular, genetic and biochemical analyses. Thus, many of the processes that underlie embryogenesis are beginning to be understood. In this chapter, we focus on genes that play key roles in the morphogenesis phase of Arabidopsis embryogenesis. [ABSTRACT FROM AUTHOR]

In this work, we present experimental results corresponding to H2 adsorption at high pressures and different temperatures (77 and 298 K) for a wide variety of carbons materials in order to analyze the effect of the porosity on the H2 adsorption capacities in gravimetric basis. Likewise, we point out the importance of the packing density of the materials in order to obtain high H2 adsorption capacities in volumetric basis and high total storage capacities. At 298 K, the H2 adsorption capacity depends on both the total micropore volume and the micropore size distribution. At 77 K, H2 adsorption depends only on the total micropore volume of the carbon material. Packing density of the carbon materials decreases with increasing the porosity development. Therefore, a good balance between porosity and packing density is needed. The total H2 storage on the best activated carbon at 298 K and 20 MPa is 16.7 g H2/L and 38.8 g H2/L at 77 K and 4 MPa. Keywords: active carbon; hydrogen adsorption; hydrogen storage; packing density [ABSTRACT FROM AUTHOR]

In the present work, we studied the effect of the mineral content (hydroxyapatite), on the thermal stability of the bone collagen matrix. The demineralization process was followed measuring the percentage of remaining mass and characterized by Fourier Transform Infra Red Spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC), using a Calcium chelant agent (EDTA). A 52 % loss of the initial weight was observed after 72 hours of treatment, associated with a decrease of the mineral content, indicated by changes in the intensity of the peaks correspondent to PO4-3 vibrations. The bone collagen's denaturalization and degradation temperatures was followed by DSC, showing an endotherm in 166° C for the untreated bone and in 113°C for the 72 hours treated bone, correspondent both to the bone collagen denaturalization temperature. The thermogram for the 12 hours demineralized exhibited a small endotherm in 250°C, corresponding to slight degradation, for the 72 hours treated bone the endotherm decreased to 230° C, correspondent to the bone collagen degradation. The above results lead us to conclude that the bone collagen triple helix losses its thermal stability when the interactions with the surrounding hydroxyapatite are eliminated. [ABSTRACT FROM AUTHOR]

A Single-Trial detection for Evoked Potentials is presented, it was tested with Event Related Potentials (oddball) which are used in the Donchin's Speller. The scheme is based in inner product of registered potentials over signal subspaces, estimated by principal components analysis. Different combinations of projection coefficients were used as characteristic vectors for a gaussian Support Vector Machine classifier. To assess the scheme performance, the ROC area and accuracy were evaluated. Procedures were tested on 9 healthy subjects. Results suggest that the scheme could be used on line. [ABSTRACT FROM AUTHOR]

The main goal of this study is to design a foot prosthesis for transtibial amputees that can be produced in Colombia and reaches the performance requirements for an active lifestyle. The material meant for this purpose is a carbon fiber composite due to is high strength, modulus and stiffness and moderate cost. The matrix of the composite is a low modulus epoxy resin to ensure a fiber-dominated strength case. The prosthesis is designed for the average Colombian amputee, weighting 80kg (175lb) and having foot dimensions 27cm (10.6in) long and 8cm (3.15in) wide, and for a high activity level, in which vertical forces can reach up to 350% of bodyweight. The prosthesis is designed using mathematical models and validated using Finite Element Analysis software. The design includes the foot prosthesis and an aluminum alloy pyramid adapter. The prosthesis is intended to be manufactured initially by lamination and later by vacuum infusion and water cutting pretending to be produced, in a near future, at a scale that answers the need of foot prosthesis in Colombia. [ABSTRACT FROM AUTHOR]

Blends and/or composites of HDPE, type I collagen gel extracted from rat tails and dried in presence of sodium acetate, poly(ethylene -co- acrylic acid) (a compatibilizg agent) and hydroxiapatite were studied. Differential Scanning Calorimetry (DSC) analyses demonstrated that the collagen gel was able to tolerate the processing conditions of HDPE since it kept its characteristic denaturalization temperature. Transmision Electronic Microscopy (TEM) showed that the fibrillar structure of collagen was kept and it finds itself dispersed on the HDPE matrix. Collagen supplies an important reinforcement to HDPE by increasing 2,7 times the HDPE Young's modulus values. The compatibilizing agent did not show any important contribution to the Young's modulus of the HDPE/collagen/copolymer blend in comparison with the blend where no compatibilizing was used. On the other hand, the HDPE/HA blends showed a Young's modulus about two times that of pure HDPE, due to the HA crystals which confer stiffness to the whole system. [ABSTRACT FROM AUTHOR]

In the bone tissue, collagen is the most abundant protein, conforming 90% of the organic matrix of this mineralized structure. Different works indicate that in postmenopausal osteoporosis, the early degradation of the bone tissue seems to be due to the presence of bone collagen in a condition of overglycosylation, especially in the trabecular bone. To understand the role of the glycosylation of the collagen molecule and how it can regulate functions of the bone cells, such as cellular adhesion and biomineralization, is the main objective of the present work. 8 rats were ovariectomized and another 8 were sham-operated (control group). After 45 days the rats were sacrificed, femurs were extracted and the bones were decalcified in order to obtain the collagen matrix mineral free. Primary cultures of bone cells were obtained from calvaria of neonatal rats. The adhesion and differentiation (alkaline phosphatase activity and biomineralization) of these cells were evaluated on the collagen bone matrix obtained of the ovariectomized and control rats. The results of this work show a greater adhesion of the osteoblastic cells on the bone collagen for the control group in comparison with the adhesion found for the ovariectomized group, in the first two hours. Additionally, cell FA activities and mineralization on material differ between control and ovariectomized animals bone collagen samples. In conclusion, in the present work we present evidence that suggest that bone cells can recognize differences in the degree of glycosylation of the collagen matrix in ovariectomized animals in comparison with the control group, and the cellular response is different as a consequence of these variations of the extracellular material. [ABSTRACT FROM AUTHOR]

Bone healing and growth are controlled by the rate of deposition of hydroxyapatite (HA). This process have been so far accredited to the work of osteoblasts, which are attracted by the electrical dipoles produced either by piezoelectricity, due to deformation of the bone, specially the collagen in it, or due to outside electrical stimuli. The main purpose of this work was to study the influence of the cortical bone collagen piezoelectricity effect, on the osteoblastic cells orientation. To evaluate the cellular adhesion on the cortical bone collagen subject to deformation, bone cells of newborn calvaria's rats were extracted. The bone collagen was prepared and deformed following the specifications described in earlier studies. The results of this study shown that the piezoelectric phenomena of bone collagen promotes the cell's adhesion on the compression side more than tension side compared with undeformed surface. Further studies ascertaining the osteoblastic activity due to the electric field are being advanced. [ABSTRACT FROM AUTHOR]

This paper presents an implementation of an effective synchronization between a registration and a stimulation module that form part of a steady state visual evoked potential (SSVEP)-based Brain Computer Interface (BCI). Each of the synchronized modules were created and designed in two different platforms as well as in two different workstations, so a particular objective of this work consisted in finding the best platforms to stimulate and register the EEG in order to create a communication channel and protocol between the two different modules. The resulting synchronization was tested with an existing SSVEP stimulation protocol in one subject. Even though the results were promising, a test on a bigger population is needed. [ABSTRACT FROM AUTHOR]

For the diagnosis of glaucoma, we propose a system of Artificial Intelligence that employs Artificial Neural Networks (ANN) and integrates the analysis of the nerve fibres of the retina from the study with scanning laser polarimetry (NFAII;GDx), perimetry and clinical data. The present work shows an analysis of 106 eyes of 53 patients, in accordance with the stage of glaucomatous illness in which each eye was found. The groups defined include stage 0, which corresponds to normal eyes; stage 1, for ocular hypertension; 2, for early glaucoma; 3, for established glaucoma; 4, for advanced glaucoma and 5, for terminal glaucoma. The developed ANN is a multilayer perceptron provided with the Levenberg-Marquardt method. The learning was carried out with half of the data and with the training function of gradient descent w/momentum backpropagation and was checked by the diagnosis of a glaucoma expert ophthalmologist. The other half of the data served to evaluate the model of the neuronal network. A 100% correct classification of each eye in the corresponding stage of glaucoma has been achieved. Specificity and sensitivity are 100%. This method provides an efficient and accurate tool for the diagnosis of glaucoma in the stages of glaucomatous illness by means of AI techniques. [ABSTRACT FROM AUTHOR]

Attempting to obtain a classifier or a model from datasets could be a cumbersome task, specifically in datasets with a high dimensional datasets. The larger the amount of features the higher the complexity of the problem, and the larger the time expended in generating the outcome -the classifier or the model-. Feature selection has been proved as a good technique for eliminating features that do not add information of the system. There are several different approaches for feature selection, but until our knowledge there are not many different approaches when feature selection is involved with imprecise data and genetic fuzzy systems. In this paper, a feature selection method based on the fuzzy mutual information is proposed. The outlined method is valid either for classifying problems when expertise partitioning is given, and it represents the base of future work including the use of the in case of imprecise data. [ABSTRACT FROM AUTHOR]

Chapter 7 of the book "Ideologies of Education: Unmasking the Trap of Teacher Neutrality" is presented. The author advises teachers to understand the ideological aspects of literacy in order for them to help their students from non-dominant cultures master the discourse that they need to participate in their chosen professions. She also shares teaching strategies aimed to equip graduate students with the necessary skills for writing educational reports, such as giving them detailed written feedback and opportunities to practice the oral discourse.

Texture is a visual feature frequently used in image analysis that has associated certain vagueness. However, the majority of the approaches found in the literature do not either consider such vagueness or they do not take into account human perception to model the related uncertainty. In this paper we model the concept of "coarseness", one of the most important textural features, by means of fuzzy sets and considering the way humans perceive this kind of texture. Specifically, we relate representative measures of coarseness with its presence degree. To obtain these "presence degrees", we collect assessments from polls filled by human subjects, performing an aggregation of such assessments. Thus, the membership function corresponding to the fuzzy set "coarseness" is modelled by using as reference set the representative measures and the aggregated data. [ABSTRACT FROM AUTHOR]

We present a practical guide to some of the issues involved in comparing or integrating different microarray studies. We discuss the influence that various factors have on the agreement between studies, such as different technologies and platforms, statistical analysis criteria, protocols, and lab variability. We discuss methods to carry out or refine such comparisons, and detail several common pitfalls to avoid. Finally, we illustrate these ideas with an example case. [ABSTRACT FROM AUTHOR]

Human rights education is increasingly emphasized worldwide in organizational, curricular and discursive developments (Andreopoulos and Claude 1997; Elbers 2002). We analyze this expansion, with information on both world- and national-level educational patterns. [ABSTRACT FROM AUTHOR]

There is an increasing need for accurate forest inventories to assist forest managers and decision makers in the planning of the forest resources. Airborne LiDAR methods enable the construction of Tree Canopy Models (TCM) at a fine resolution, which allow the delineation of individual tree crowns. This information can be useful for the prediction of forest parameters such as top height, basal area, standing volume and biomass. In this paper, we present a comparative analysis of the algorithms developed independently by Gougeon (1995), Popescu (2003) and Weinacker (2004a) for delineating individual tree crowns and as a means to extract forest parameters. The comparison was achieved as follow. Firstly, the algorithms were tested in their efficiency for delineating tree crowns. Secondly, single tree parameters were estimated using the crown delineation and finally, stand parameters were estimated by averaging single tree parameters. Results of the three algorithms were compared to each other and to field measurement for validation. The results showed that the algorithm by Popescu was the most suitable method to delineate crowns with 89% accuracy. However only 72% were linked with actual trees measured in the field. The algorithm by Popescu was the most suitable to estimate individual tree height with s RMSE (%) of 1.93 m (8.1%). The algorithm by Gougeon was the most suitable to estimate individual crown diameter and stem diameter with a RMSE (%) of 1.81 m (31.7%) and 7.05 cm (21.8%) respectively. The algorithm by Popescu was the most suitable to estimate top height with a RMSE (%) of 0.94 m (3.8%). Finally, the algorithm by Weinacker was the most suitable to estimate stand basal area and volume with a RMSE (%) of 9.10 m2/ha (24.3%) and 119.7 m3/ha (29.4%) respectively. [ABSTRACT FROM AUTHOR]

Kelvin effect (Skin effect) is used in surface hardening produced by induction heating of gears, cam forms, camshafts and other work pieces of fairly complex geometries. The induction heating equipment for surface hardening of metals and alloys using LF (medium frequencies in the jargon of induction heating) is composed by a coil or coil assembly and a power semiconductor driving system up to 50 kHz. The load seen by the driving system is equivalent to a transformer. The primary corresponds to the excitation coil or coil assembly, and the work piece corresponds to a short-circuited secondary. In these and others technical applications of Kelvin effect it is often necessary to be able to relate local skin depths with local curvatures of the surface of electrically conductive bodies. It was proposed recently a closed form analytical formula that relates the local skin depth with the local mean curvature and the well known skin depth for a flat conductive but non ferromagnetic body. The purpose of this paper is threefold. First, improve and give a critical discussion of the derivation of the aforementioned analytical formula. Second, generalize it to bodies with magnetic hysteresis losses. Third, apply the above mentioned generalized formula to describe the electrical load seen by the driving system in the conditions used for surface hardening. The formulae given here could be applied to asses some characteristics of the load that may be of interest in the choice or design of the driving system, including the planning of digital simulations using complex computer codes. Index Terms Induction heating, Load impedance modeling, Skin effect, Mean curvature, Hysteresis losses. [ABSTRACT FROM AUTHOR]

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Acquisition systems are not fully reliable since any real sensor will provide noisy and possibly incomplete and degraded data. Therefore, in tensor measurements, all problems dealt with in conventional multidimensional statistical signal processing are present with tensor signals. In this chapter we describe some noniterative approaches to tensor signal processing. Our schemes are achieved by the estimation of a local structure tensor, which is used as a key element in regularization. A stochastic point of view as well as a phase-invariant implementation are presented. This work also covers tensor extensions for common scalar operations such as anisotropic interpolation and filtering. An application of the structure tensor for regularization of deformation fields in tensor image registration is also shown. The techniques presented in this chapter suppose an alternative to variational and PDEs schemes, and another point of view of the tensor signal processing. [ABSTRACT FROM AUTHOR]

Many users require IP networks with the capacity to guarantee a minimum throughput even during periods of congestion. Furthermore, it is also desirable to share the excess unsubscribed bandwidth among active users if aggregate demand does not exceed network capacity. This kind of service, named assured service, can be provided through the Assured Forwarding (AF) Per Hop Behavior (PHB) defined in the DiffServ architecture. DiffServ mechanisms require special networking support at both the edge and the core nodes to guarantee the differentiated service. In this paper we propose the Ping Trunking scheme as a suitable mechanism to provide assured services to network users without the need for modifying core nodes. Ping Trunking is an edge-to-edge management technique that completely addresses the regulation of aggregate traffic streams at the edge of the network. In addition, it also overcomes some unfairness issues found in AF when sharing the available bandwidth among heterogeneous aggregates. Simulation results have validated the effectiveness of our proposal. Keywords: DiffServ, assured services, aggregated traffic, congestion control. [ABSTRACT FROM AUTHOR]

This paper describes a face detection system conceived to process video streams in real-time. Cue combination allows the system to tackle the temporal restrictions achieving a notable detection rate. The system developed is able to detect simultaneously at different resolutions multiple individuals building a feature based model for each detected face. [ABSTRACT FROM AUTHOR]

The Computational Neuroscience has as main goal the understanding of the computational style of the brain and developing artificial systems with brain capabilities. Our paper belongs to this field. We will use an Hebbian neural ensemble which follow a non-linear differential equation system namely Hebbian System (HS), which represent the neurodynamics and the adaptation in accordance with the Hebb's postulate, to study the influence of the NO diffusion in the Hebbian learning. Considering that the postsynaptic neurons provide retrograde signals to the presynaptic neurons [1] we suggest the NO as a probable biological support to the Hebb's law propounding a new mathematical formulation of that learning law, the diffusive Hebb's law. We will present a study of the behavior of the diffusive Hebb's law using a Diffusive Hebbian System (DHS). [ABSTRACT FROM AUTHOR]

This paper presents an approach for the automatic speech re-cognition using syllabic units. Its segmentation is based on using the Short-Term Total Energy Function (STTEF) and the Energy Function of the High Frequency (ERO parameter) higher than 3,5 KHz of the speech signal. Training for the classification of the syllables is based on ten related Spanish language rules for syllable splitting. Recognition is based on a Continuous Density Hidden Markov Models and the bigram model language. The approach was tested using two voice corpus of natural speech, one constructed for researching in our laboratory (experimental) and the other one, the corpus Latino40 commonly used in speech researches. The use of ERO parameter increases speech recognition by 5% when compared with recognition using STTEF in discontinuous speech and improved more than 1.5% in continuous speech with three states. When the number of states is incremented to five, the recognition rate is improved proportionally to 97.5% for the discontinuous speech and to 80.5% for the continuous one. [ABSTRACT FROM AUTHOR]

Ontologies have seen quite an enormous development and application in many domains within the last years, especially in the context of the next web generation, the Semantic Web. Besides the work of countless researchers across the world, industry starts developing ontologies to support their daily operative business. Currently, most ontologies exist in pure form without any additional information, e.g. authorship information, such as provided by Dublin Core for text documents. This burden makes it difficult for academia and industry e.g. to identify, find and apply - basically meaning to reuse - ontologies effectively and efficiently. Our contribution consists of (i) a proposal for a metadata standard, so called Ontology Metadata Vocabulary (OMV) which is based on discussions in the EU IST thematic network of excellence Knowledge Webhttp://knowledgeweb.semanticweb.org/ and (ii) two complementary reference implementations which show the benefit of such a standard in decentralized and centralized scenarios, i.e. the Oyster P2P system and the Onthology metadata portal. [ABSTRACT FROM AUTHOR]

The increasing flow of digital information requires the extraction, filtering and classification of pertinent information from large volumes of texts. An important preprocessing tool of these tasks consists of name entities recognition, which corresponds to a Name Entity Recognition (NER) task. In this paper we propose a completely automatic NER which involves identification of proper names in texts, and classification into a set of predefined categories of interest as Person names, Organizations (companies, government organizations, committees, etc.) and Locations (cities, countries, rivers, etc). We examined the differences in language models learned by different data-driven systems performing the same NLP tasks and how they can be exploited to yield a higher accuracy than the best individual system. Three NE classifiers (Hidden Markov Models, Maximum Entropy and Memory-based learner) are trained on the same corpus data and after comparison their outputs are combined using voting strategy. Results are encouraging since 98.5% accuracy for recognition and 84.94% accuracy for classification of NE for Spanish language were achieved. [ABSTRACT FROM AUTHOR]

Question Classification (QC) is usually the first stage in a Question Answering system. This paper presents a multilingual SVM-based question classification system aiming to be language and domain independent. For this purpose, we use only surface text features. The system has been tested on the TREC QA track questions set obtaining encouraging results. [ABSTRACT FROM AUTHOR]