Search results for: Catherine Kuforiji

Authors: Catherine Kuforiji, Michel Nganbe

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The abrasive wear of composite materials is a major challenge in highly demanding wear applications. Therefore, this study focuses on fabricating, testing and assessing the properties of 50wt% SS316L stainless steel–50wt% Al2O3 particle composites. Composite samples were fabricated using the powder metallurgy route. The effects of the powder metallurgy processing parameters and hard particle reinforcement were studied. The microstructure, density, hardness and toughness were characterized. The wear behaviour was studied using pin-on-disc testing under dry sliding conditions. The highest hardness of 1085.2 HV, the highest theoretical density of 94.7% and the lowest wear rate of 0.00397 mm3/m were obtained at a milling speed of 720 rpm, a compaction pressure of 794.4 MPa and sintering at 1400 °C in an argon atmosphere. Compared to commercial SS316 and fabricated SS316L, the composites had 7.4 times and 11 times lower wear rate, respectively. However, the commercial 90WC-10Co showed 2.2 times lower wear rate compared to the fabricated SS316L-Al2O3 composites primarily due to the higher ceramic content of 90 wt.% in the reference WC-Co. However, eliminating the relatively high porosity of about 5 vol% using processes such as HIP and hot pressing can be expected to lead to further substantial improvements of the composites wear resistance.

Keywords: SS316L, Al2O3, powder metallurgy, wear characterization

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Authors: Apotiola Z. O., Anyakorah C. I., Kuforiji O. O.

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Sensory and microbial properties of fresh and canned Calocybe indica (milky mushroom) were evaluated. The mushroom was grown under a controlled environment with hardwood (Cola nitida) and rice bran substrate (4:1) canned in a brine solution of salt and citric acid. Analysis was carried out using standard methods. The overall acceptability ranged between 5.62 and 6.50, with sample S30 adjudged the best. In all, significant differences p<0.01 exist in the panelist judgment. Thus, the incorporation of salt and citric acid at 3.5g and 1.5g, respectively, improved sensory attributes such as texture, aroma, color, and overall acceptability. There was no coliform and fungi growth on the samples throughout the storage period. The bacterial count, on the other hand, was observed only in the fifth and sixth week of the storage period which varied between 0.2 to 0.9 x 103 cfu/g. The highest value was observed in sample S20 of the sixth week of storage, while the lowest value was recorded in sample S30 of the sixth week of storage. Based on 16S rRNA gene sequencing, bacterial species were taxonomically confirmed as Bacillus thuringiensis. The percentile compositions and Sequence ID of the bacterial species in the mushroom was 90%.

Keywords: bacterial count, microbial property, sensory, sawdust, texture

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Authors: Catherine Felce, Lior Pachter

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Current methods for building phylogenetic trees from gene expression data consider mean expression levels. With single-cell technologies, we can leverage more information about cell dynamics by considering the entire distribution of gene expression across cells. Using biophysical modeling, we propose a method for constructing phylogenetic trees from scRNA-seq data, building on Felsenstein's method of continuous characters. This method can highlight genes whose level of expression may be unchanged between species, but whose rates of transcription/decay may have evolved over time.

Keywords: phylogenetics, single-cell, biophysical modeling, transcription

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Authors: Catherine Bernard, Paul Ransom

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Recent events have prompted emergency planners to re-evaluate their emergency response to major incidents and mass casualties. At the Royal Sussex County Hospital, we have adopted a tiered system comprised of three levels, anticipating an increasing P1, P2 or P3 load. This will aid planning in the golden period between Major Incident ‘Standby,’ and ‘Declared’. Each tier offers step-by-step instructions on appropriate patient movement within and out of the department, as well as suggestions for overflow areas and additional staffing levels. This system can be adapted to individual hospitals and provides concise instructions to be followed in a potentially overwhelming situation.

Keywords: disaster planning, emergency preparedness, major incident planning, mass casualty event

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Authors: Brian F. Estidola, Alfredo A. Alcantara, Catherine del Cruz, Genelita S. Garcia

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This study aimed to investigate the effects of testosterone in the development and growth of Aedes aegypti as a main vector of dengue virus. There were three concentrations of testosterone: (0µM), (10µM), and (15µM) arranged randomly in two blocks. Each concentration houses 10 mosquitoes and monitored their development. The results showed that there were no significant differences on the effects of testosterone in emergence of larvae, mortality of eggs and larvae. However, it was shown that adults emerged from 15µM had a lower sex ratio than 10µM leading to the conclusion that there could be an optimal concentration of testosterone close to 10µM that could led to a high possibility of sex reversal of adult mosquitoes from female to male.

Keywords: mosquito, sex reversal, testosterone, ecdysterone

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Authors: Catherine Omole

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Examination malpractice includes acts that temper with collecting accurate results during the conduct of an examination, thereby giving undue advantage to a student over his colleagues. Even though examination malpractice has been a lingering problem, examinations may not be easy to do away with completely as it is an important feedback tool in the learning process with several other functions e.g for the purpose of selection, placement, certification and promotion. Examination malpractice has created a lot of problems such as a relying on a weak work force based on false assessment results. The question is why is this problem still persisting, despite measures that have been taken to curb this ugly trend over the years? This opinion paper has identified modifications that could help relieve the student of the examination stress and thus increase the student’s effort towards effective learning and discourage examination malpractice in the long run.

Keywords: assessment, examination malpractice, learning, science classroom

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Authors: Lema Catherine Forje

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Innovation activates the system of an economy to a new level. Innovation follows a process. The first step in innovation is the idea-generation process. There is widespread appreciation that people go to great lengths, incur expenses: energy and materials to generate innovative ideas. People get inspired, create, and connect. The inspiration also enables the building of a culture of innovation. Data collection was done through a face-to-face interview with the producer of the first Cameroon beer that came out in the early 1960s, a rice producing company, a cement producing company, and 100 women following a type of dressing commonly worn by Cameroonian women (wrappa). There were a total number of one hundred and three interviewees. The implication of this study is for everybody. It sheds light on the factors that are likely to sustain an innovation. Conclusion emphasises continuous research to keep giving the innovation a face lift.

Keywords: entrepreneurship, ideas, innovation, sustainability

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Authors: Catherine Bernard

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The maldistribution of clinicians within countries is well documented. It is a common theme throughout the world that rural areas often struggle to recruit and retain health workers resulting in inadequate healthcare for many. This paper will concentrate on the responsibilities that medical schools may have in addressing this shortage of rural health workers. Recommendations are made with regards to targeted rural student admissions, rurally-based medical schools, rural clinical rotations and a curriculum orientated towards rural health issues. The evidence gathered suggests that individual factors are positive in encouraging health workers to practice in rural locations. However, there is strength in numbers, and combining all the recommendations will likely result in a synergistic effect, thereby increasing numbers of rural health workers and achieving accessible healthcare for those living in rural populations.

Keywords: medical education, medical education design, public health, rural health

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Authors: Catherine K. Derow

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Possibly a slime mold somehow mutated or already was mutated at progeniture and so stayed as a metazoan when it developed into the fruiting stage and so the slime mold(s) we are evolved and similar to are genetically differ from the slime molds in existence now. This may be why there are genetic links between humans and other metazoa now alive and slime molds now alive but we are now divergent branches of the evolutionary tree compared to the original slime mold, or perhaps slime mold-like organisms, that gave rise to metazoan animalia and perhaps algae and plantae as slime molds were undifferentiated enough in many ways that could allow their descendants to evolve into these three separate phylogenetic categories. Or it may be a slime mold was born or somehow progenated as multicellular, as the particular organism was mutated enough to have say divided in a a 'pseudo-embryonic' stage, and this could have happened for algae, plantae as well as animalia or all the branches may be from the same line but the missing link might be covered in 'phylogenetic sequence comparison noise'.

Keywords: metazoan evolution, unicellular bridge to metazoans, evolution, slime mold

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Authors: Noha Al Majid, Said Mazer, Moulhime El Bekkali, Catherine Algani, Mahmoud Mehdi

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A low noise figure (NF) and high linearity V-band Low Noise Amplifier (LNA) is reported in this article. The LNA compromises a three-stage cascode configuration. This LNA will be used as a part of a WPAN (Wireless Personal Area Network) receiver in the millimeter-wave band at 60 GHz. It is designed according to the MMIC technology (Monolithic Microwave Integrated Circuit) in PH 15 process from UMS foundry and uses a 0.15 μm GaAs PHEMT (Pseudomorphic High Electron Mobility Transistor). The particularity of this LNA compared to other LNAs in literature is its very low noise figure which is equal to 1 dB and its high linearity (IIP3 is about 22 dB). The LNA consumes 0.24 Watts, achieving a high gain which is about 23 dB, an input return loss better than -10 dB and an output return loss better than -8 dB.

Keywords: low noise amplifier, V-band, MMIC technology, LNA, amplifier, cascode, pseudomorphic high electron mobility transistor (PHEMT), high linearity

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Authors: Maryam Abata, Moulhime El Bekkali, Said Mazer, Catherine Algani, Mahmoud Mehdi

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One major problem of most electronic systems operating in the millimeter wave band is the signal generation with a high purity and a stable carrier frequency. This problem is overcome by using the combination of a signal with a low frequency local oscillator (LO) and several stages of frequency multipliers. The use of these frequency multipliers to create millimeter-wave signals is an attractive alternative to direct generation signal. Therefore, the isolation problem of the local oscillator from the other stages is always present, which leads to have various mechanisms that can disturb the oscillator performance, thus a buffer amplifier is often included in oscillator outputs. In this paper, we present the study and design of a buffer amplifier in the mm-wave band using a 0.15μm pHEMT from UMS foundry. This amplifier will be used as a part of a frequency quadrupler at 60 GHz.

Keywords: Mm-wave band, local oscillator, frequency quadrupler, buffer amplifier

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Authors: Arwa Khannoussi, Alexandru-Liviu Olteanu, Pritesh Narayan, Catherine Dezan, Jean-Philippe Diguet, Patrick Meyer, Jacques Petit-Frere

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Due to the nature of autonomous Unmanned Aerial Vehicles (UAV) missions, it is important that the decisions of a UAV stay consistent with the priorities of an operator, while at the same time allowing them to be easily audited and explained. We propose a multi-layer decision engine that integrates the operator (human) preferences by using the Multi-Criteria Decision Aiding (MCDA) methods. A software implementation of a UAV simulator and of the decision engine is presented to highlight the advantage of using such techniques on high-level decisions. We demonstrate that, with such a preference-based decision engine, the decisions of the UAV are compatible with the priorities of the operator, which in turn increases her/his confidence in its autonomous behavior.

Keywords: autonomous UAV, multi-criteria decision aiding, multi-layers decision engine, operator's preferences, traceable decisions, UAV simulation

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Authors: Catherine Coron

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This paper first tries to scrutinize the diverse meanings and policies of inclusive education in the United Kingdom and France in the recent period thanks to a comparative analysis of the recent literature as well as the various definitions, legislation and good practices of inclusive education. The central question is to find the links between inclusion and economic wellbeing in the economic, social and cultural context of the two countries. The first part questions the economic, social and cultural meaning of the definitions thanks to a comparison between the various perspectives to envisage the notions of inclusion and wellbeing in the two countries in order to better understand the way they are interpreted according to each cultural background. The second part analyses the various policies implemented recently in order to determine the main characteristics, the differences, and the similarities, as well as the economic challenges in terms of wellbeing. The final goal of this paper is to identify the main economic, social and cultural values as regards sustainability in each country.

Keywords: education, inclusion, students with special needs, wellbeing

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Authors: Raymond C. Hawkins II, Catherine A. Hawkins

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The System Contextual Integrated Model (SCIM), developed as a trans-theoretical framework for selecting measures for psychotherapy process and outcome, is reformulated for behavioral health applications. The SCIM “healing cycle” is an allostatic hedonic affective-cognitive right-hemisphere–left-hemisphere coordinated process involving positive alliesthesia that mitigates traumatic pain and generates psychological flexibility. The SCIM “trauma cycle” is an allostatic overload alliesthesia opponent process with long-lasting pathology sequelae. The social ecological context moderates the “healing cycle” and the “trauma cycle.” Repeated evocation of the “healing cycle” in a therapeutic relationship can gradually relieve trauma sequelae. The SCIM is applied to pain, obese binge eating, and substance use disorders.

Keywords: allostasis, alliesthesia, opponent process, behavioral health, assessment

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Authors: Catherine Maware, Olufemi Adetunji

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The paper is aimed at developing a model to measure the impact of Lean manufacturing deployment on organizational performance. The model will help industry practitioners to assess the impact of implementing Lean constructs on organizational performance. It will also harmonize the measurement models of Lean performance with the house of Lean that seems to have become the industry standard. The sheer number of measurement models for impact assessment of Lean implementation makes it difficult for new adopters to select an appropriate assessment model or deployment methodology. A literature review is conducted to classify the Lean performance model. Pareto analysis is used to select the Lean constructs for the development of the model. The model is further formalized through the use of Structural Equation Modeling (SEM) in defining the underlying latent structure of a Lean system. An impact assessment measurement model developed can be used to measure Lean performance and can be adopted by different industries.

Keywords: impact measurement model, lean bundles, lean manufacturing, organizational performance

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Authors: Catherine Equey Balzli

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Old age retirement pensions are an important concern among the Swiss but estimating one’s income after retirement is difficult due to the Swiss insurance system’s complexity. This project’s aim is to prepare for developing a digital platform that will allow individuals to plan for retirement in a simplified manner. The main objective of the platform will be to give individuals the tools to check that their savings and retirement benefits will allow them to continue the lifestyle to which they are accustomed once they are retired. The research results from qualitative (focus group) and quantitative (survey) methodologies, recommend the scope and functionalities for a digital platform to be developed. A main outcome is the need to limit the platform’s scope to old-age pension only (excluding survivors’ or disability pensions, for instance). Furthermore, an outcome regarding the functionalities is the proposition of scenarios such as early retirement, changes to income, or modifications to personal status. The development of the digital platform will be a subsequent project.

Keywords: benefit statement, digital platform, retirement financial planning, social insurance

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Authors: Louis Denis Kevin Catherine, Raja Aziz Raja Ma’arof, Azrina Arshad, Sangeeth Suresh

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Machining parameters are very important in determining the surface quality of any material. In the past decade, some new engineering materials were developed for the manufacturing industry which created a need to conduct an investigation on the impact of the said parameters on their surface roughness. The polyurethane (PU) block is widely used in the automotive industry to manufacture parts such as checking fixtures that are used to verify the dimensional accuracy of automotive parts. In this paper, the design of experiment (DOE) was used to investigate the effect of the milling parameters on the PU block. Furthermore, an analysis of the machined surface chemical composition was done using scanning electron microscope (SEM). It was found that the surface roughness of the PU block is severely affected when PU undergoes a flood machining process instead of a dry condition. In addition, the step over and the silicon content were found to be the most significant parameters that influence the surface quality of the PU block.

Keywords: polyurethane (PU), design of experiment (DOE), scanning electron microscope (SEM), surface roughness

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Authors: Angelo Lanzilotto, Martin Kuss-Petermann, Catherine E. Housecroft, Edwin C. Constable, Oliver S. Wenger

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We recently described the synthesis of a new tetraphenylporphyrinatozinc(II)-conjugated 2,2':6',6"-terpyridine (1) in which the tpy domain enables the molecule to act as a metalloligand. The synthetic route to 1 has been optimized, the importance of selecting a particular sequence of synthetic steps will be discussed. Three homoleptic complexes have been prepared, [Zn(1)₂]²⁺, [Fe(1)₂]²⁺ and [Ru(1)₂]²⁺, and have been isolated as the hexafluoridophosphate salts. Spectroelectrochemical measurements have been performed and the spectral changes ascribed to redox processes are partitioned on either the porphyrin or the terpyridine units. Compound 1 undergoes a reversible one-electron oxidation/reduction. The removal/gain of a second electron leads to a further irreversible chemical transformation. For the homoleptic [M(1)₂]²⁺ complexes, a suitable potential can be chosen at which both the oxidation and the reduction of the {ZnTPP} core are reversible. When the homoleptic complex contains a redox active metal such as Fe or Ru, spectroelectrochemistry has been used to investigate the metal to ligand charge transfer (MLCT) transition. The latter is sensitive to the oxidation state of the metal, and electrochemical oxidation of the metal center suppresses it. Detailed spectroelectrochemical studies will be presented.

Keywords: homoleptic complexes, spectroelectrochemistry, tetraphenylporphyrinatozinc(II), 2, 2':6', 6"-terpyridine

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Authors: Androniki-Anna Doulgeroglou, Panagiotis Kotronis, Giulio Sciarra, Catherine Bouillon

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The interaction diagrams are functions that define ultimate states expressed in terms of generalized forces (axial force, bending moment and shear force). Two characteristic states for reinforced concrete (RC) sections are proposed: the first characteristic state corresponds to the yield of the reinforcement bars and the second to the peak values of the generalized forces generalized displacements curves. 3D numerical simulations are then conducted for RC columns and the global responses are compared to experimental results. Interaction diagrams for combined flexion, shear and axial force loading conditions are numerically produced for symmetrically RC square sections for different reinforcement ratios. Analytical expressions of the interaction diagrams are also proposed, satisfying the condition of convexity. Comparison with interaction diagrams from the Eurocode is finally presented for the study cases.

Keywords: analytical convex expressions, finite element method, interaction diagrams, reinforced concrete

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Authors: Chika Catherine Ayogu

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Rehabilitation plays an important and integral part in the life of roadway rehabilitation management system. It is a systematic method for inspection and rating the roadway condition in a given area. The system performs a cost effective analysis of various maintenance and rehabilitation strategies. Finally the system prioritize and recommend roadway rehabilitation and maintenance to maximize results within a given budget amount. During execution of maintenance activity, the system also tracks labour, materials, equipment and cost for activities performed. The system implements physical assessment field inspection and rating of each street segment which is then entered into a database. The information is analyzed using a software, and provide recommendations and project future conditions. The roadway management system provides a deterioration curve for each segment based on input then assigns the most cost-effective maintenance strategy based on conditions, surface type and functional classification, and available budget. This paper investigates the roadway management system and its capabilities to assist in applying the right treatment to the right roadway at the right time so that expected service life of the roadway is extended as long as possible with acceptable cost.

Keywords: effectiveness, rehabilitation, roadway, software system

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Authors: Andrew T. Hendrickson, Liven De Marez, Marijn Martens, Gytha Muller, Tudor Paisa, Koen Ponnet, Catherine Schweizer, Megan Van Meer, Mariek Vanden Abeele

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Quantifying and understanding the myriad ways people use their phones and how that impacts their relationships, cognitive abilities, mental health, and well-being is increasingly important in our phone-centric society. However, most studies on the patterns of phone use have focused on theory-driven tests of specific usage hypotheses using self-report questionnaires or analyses of smaller datasets. In this work we present a series of analyses from a large corpus of over 3000 users that combine data-driven and theory-driven analyses to identify reliable smartphone usage patterns and clusters of similar users. Furthermore, we compare the stability of user clusters across user- and system-initiated sessions, as well as during the hypothesized ritualized behavior times directly before and after sleeping. Our results indicate support for some hypothesized usage patterns but present a more complete and nuanced view of how people use smartphones.

Keywords: data mining, experience sampling, smartphone usage, health and well being

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Authors: Catherine Portelli

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Felines, such as Panthera tigris, Panthera leo and Puma concolor, have become common residents in animal parks and zoos. They often sustain injuries from other felines within the same, or adjacent enclosures and from playing with items of enrichment and structures of the enclosure itself. These open wounds, and their treatments, are often challenging in the veterinary practice, where feline-specific studies are lacking. This study is based on the author’s clinical experience gained while working at local animal parks in the past five years, and current evidence of hydrocolloid dressing applied to other species. Hydrocolloid dressing is used for secondary healing of chronic and acute wounds, where there is a considerable amount of tissue loss. The patients included in this study were sedated using medetomidine and ketamine every three to four days, for wound treatment and bandage change. Comparative studies of different techniques of open wound management will improve the healing process of exotic felines in the future by decreasing the time of recovery and incidence of other complications. Such studies will also aid with treatment of injuries sustained in wild felines, such as trap and bite wounds, found in natural conservation areas and wild animal sanctuaries.

Keywords: felines, hydrocolloid dressing, open wound, secondary healing

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Authors: Catherine Cheetam, Alan Harper, Melody Elliott, Mika Ito

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This paper describes a pilot study conducted with English as a foreign language (EFL) students at a private university in Japan who used graded readers and the MReader website in class or independently to enhance their English reading skills. Each semester students who read 100,000 words with MReader quizzes passed enter into the ‘MReader Challenge,’ a reading contest that recognizes students for their achievement. The study focused specifically on the attitudes of thirty-six EFL students who successfully completed the Challenge in the 2015 spring semester using graded readers and MReader, and their motivation to continue using English in the future. The attitudes of these students were measured using their responses to statements on a Likert scaled survey. Follow-up semi-structured interviews were conducted with eleven students to gain additional insight into their opinions. The results from this study suggest that reading graded readers in general promoted intrinsic motivation among a majority of the participants. This study is preliminary and needs to be expanded and continued to assess the lasting impact of the extensive reading program. Limitations and future directions of the study are also summarized and discussed.

Keywords: attitudes, extensive, intrinsic, methodolgies, motivation, reading

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Authors: Rachel Bechtold, Catherine Shoulders, Donald Johnson, Jennie Popp, Elena Garcia, Lisa Wood

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Creating successfully restored urban landscapes involves both the sound design of natural resources and the incorporation of human perceptions of landscape. Moving forward with an invested interest from society is a challenge for the efficacy of reclaimed landscape design. In particular, urban areas present a dynamic environment wherein society and nature compete for resources and space. This review is meant to examine how perceptions of urban community members, the stakeholders for the plant species that share their environment, are reflected in aesthetic considerations. Findings from this literature review include themes of (1) aesthetic perceptions of stakeholders in rehabilitated landscapes and (2) the importance of organizing indicators of aesthetic perception for future design decisions. Recommendations include addressing the gap in research on aesthetic perceptions of reclaimed urban landscapes and addressing the lack of a consistent and widely accepted framework for these interdisciplinary studies. With knowledge of stakeholder perceptions, improved aesthetic and ecologic designs can more seamlessly merge into reclaimed urban landscapes.

Keywords: phytoremediation, urban landscape design, aesthetic perception, landscape ecology, phytorestoration, landscape reclamation, rehabilitation

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Authors: Catherine Oluyemo

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In Africa, patriarchy has manifested itself in the socio-cultural, political, economic and legal institutions. The decree of the father as the male head of the family has contributed to the powerlessness of women in African nations. To buttress this perception, in his work Meno, Plato made a declaration in the platonic dialogue that the desirable quality of a man should be the capacity to administer the state, and in the administration of it to benefit his friends and harm his enemies; and he must also be careful not to suffer harm himself. Furthermore, he said: a woman's good worth may also be easily described as ordering her house, keep what is indoors, and obey her husband. The works of Aristotle portrayed women as morally, intellectually, and physically inferior to men; they saw women as the property of men; claimed that women's role in society was to reproduce and serve men in the household; and saw male domination of women as natural and virtuous. This has been sustained for ages and is incessantly impinging on the involvement of women in African leadership positions. The purpose of this paper is to make sense of the concept of patriarchy in relations to women participation in Africa leadership, and its challenges in the participation of women in the leadership positions of Africa. It seeks to discover what women should do to make their voices heard, to participate in leadership arrangements so as to actualize their potentials in contributing to the development of Africa.

Keywords: women, leadership, patriarchy, development, actualize, potentials

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Authors: Xian-Peng Jiang, Catherine C. Baucom, Toby Jiang, Robert L. Elliott

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HLA-G binds to the inhibitory receptors of uterine NK cells and plays an important role in protection of fetal cells from maternal NK lysis. HLA-G also mediates tumor escape, but the immunosuppressive role is often neglected. These studies have focused on the examination of HLA-G expression in human breast carcinoma and HLA-G immunosuppressive role in NK cytolysis. We examined HLA-G expression in breast cell lines by real time PCR, ELISA and immunofluorescent staining. We treated the breast cancer cell lines with anti-human HLA-G antibody or progesterone. Then, NK cytolysis was measured by using MTT assay. We find that breast carcinoma cell lines increase the expression of HLA-G mRNA and protein, compared to normal cells. Blocking HLA-G of the breast cancer cells by the antibody increases NK cytolysis. Progesterone upregulates HLA-G mRNA and protein of human breast cancer cell lines. The increased HLA-G expression suppresses NK cytolysis. In summary, human breast carcinoma overexpress HLA-G immunosuppressive molecules. Blocking HLA-G protein by antibody improves NK cytolysis. In contrast, upregulation of HLA-G expression by progesterone impairs NK cytolytic function. Thus, HLA-G is a new immunosuppressive checkpoint and potential cancer immunotherapeutic target.

Keywords: HLA-G, Breast carcinoma, NK cells, Immunosuppressive checkpoint

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Authors: Catherine Wright, Kate Luedke

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This paper questions whether or not individuals who had been exposed to narratives describing secure and insecure-avoidant attachment styles experienced temporary changes in their attachment style when compared to individuals who had been exposed to neutral narratives. The Attachment Style Questionnaire (or ASQ) developed by Feeney, Noller, and Hanrahan in 1994 was utilized to assess attachment style. Participants filled out a truncated version of the ASQ prior to reading the respective narratives assigned to their groups, and filled out the entirety of the ASQ after reading the narratives. Utilizing a one-way independent groups ANOVA, researchers found that the group which read the insecure-avoidant narrative experienced a statistically significant decrease in secure attachment, as did the group which read the secure narrative. The control group, however, experienced a statistically significant increase in secure attachment. Based on these findings, researchers concluded that narratives may have the ability to call attention to parental shortcomings that individuals have experienced in the forms of reminding individuals of positive experiences that they were not able to experience while spending time with their parental figures and calling attention to the shortcomings of said parental figures by reminding them of the negative experiences which they did have with them.

Keywords: attachment, insecure-avoidant, memory, secure

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Authors: Joshua I. Izegaegbe, Femi F. Oloye, Catherine E. Nasiru

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This study determined the level of manganese, zinc, copper, and nickel in the liver and muscle of the African Catfish, Clarias gariepinus from Ilushi River, Edo State, Nigeria with a view to determining the extent of contamination. Heavy metal determination of digested fish samples was done using the atomic absorption spectrophotometric method. The results show that the muscles and livers were contaminated to varying levels with the presence of some non-metallic elements. The heavy metal load revealed that zinc had the highest mean concentration of 0.217±0.008µg/g in liver and 0.130±0.006µg/g in muscle, while copper recorded the least concentration in liver 0.063±0.004µg/g and 0.027±0.003µg/gin muscle. The distribution of the heavy metals in the muscles and livers of Clarias gariepinus showed significant variations and the results also revealed that the concentration of heavy metals (Zn, Cu,Ni and Mn) found in the liver was higher than those found in the muscle. This indicates that the liver is a better accumulator of heavy metal in Clarias gariepinus than the muscles. On comparison with WHO/FAO/FEPA/USFDA standards, the study shows that the concentrations of heavy metals in liver and muscle were within permissible limits safe for human consumption.

Keywords: clarias gariepinus, heavy metals, liver, muscle

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Authors: Catherine W. Njeru, Clarence Murithi W., Isaac W. Mwangi, Ruth Wanjau, Grace N. Kiriro, Gerald W. Mbugua

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Flesh from animals is one of the most nutritious food materials that is rich in Vitamin B12, B3 (Niacin), B6, iron, zinc, selenium, and plenty of other vitamins and minerals and a high content of fats Meat consumption projection indicates an increase from 5.5 to 13.3 million tons by 2025 and this demand has been associated with livestock revolution. This study used charcoal flue gases sourced from the combustion of charcoal briquettes to prolong beef shelf life. The FT-IR technique is based on the specific absorption of infrared radiation by carbon monoxide and carbon dioxide molecules. The characterization of the functional groups was done using Fourier transform infrared spectroscopy (Shimadzu IR Tracer-100). The fresh, treated and boiled beef was ground with potassium bromide (KBr) into pellets and analyzed using FT-IR at a range of 400-3600 cm-1. The reaction of fresh, charcoal flue gas treated and boiled beef samples are as shown in the FT-IR spectrums. The fresh and boiled beef spectrums are similar, while the charcoal flue-treated beef samples show distinct peaks at 2100 and 2290 cm-1, which correspond to carbon monoxide and carbon dioxide, respectively. The study proposes the use of FT-IR in the determination of beef for consumption quality studies.

Keywords: FT-IR, charcoal flue gases, beef, charcoal flue gases

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Authors: Ikumapayi Catherine Mayowa

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The well-being of humans on a construction site is critical; abundant manpower had been lost through accidents which kill or make workers physically unfit to carry out construction activities, these, in turn, have multiple effects on the whole economy. Thus, it is necessary to put all safety items and regulations in place before construction activities can commence. This study was carried out in the Ondo state of Nigeria to investigate and analyze the state of health and safety of construction workers in the state. The study was done using first-hand observations, 50 construction project sites were visited in ten major towns of Ondo state, questionnaires were distributed, and the results were analyzed. The result shows that construction workers are being exposed to many construction site hazards due to lack of inadequate safety programs and lack of appropriate safety equipment for workers on site. From the data gotten from each site visited and the statistical analysis, it can be concluded that occurrences of an accident on construction sites depend significantly on the available safety facilities on the sites. The result of the regression statistics shows that the dependence of the frequency of occurrence of an accident on the availability of safety items on the site is 0.0362 which is less than 0.05 maximum significant level allowed. Therefore, a vital way of sustaining our building strategy is given a detail attention to the provision of adequate health and safety items on construction sites which will reduce the occurrence of accident, loss of manpower and death of skilled workers.

Keywords: construction sites, health, safety, welfare

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