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Miceli, Katharine Elizabeth. "Who's the boss? an investigation into the complex relationship between endogenous retroviruses and nearby genes." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/38133.
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Nearly half of the human and mouse genomes is composed of transposable elements (TEs) which are pieces of DNA capable of or once capable of moving to different locations in the genome. These mobile elements can potentially impact host gene expression in a variety of ways either directly through insertional mutagenesis or indirectly by serving as an alternative promoter/enhancer or through modification of splice signals. In order to protect the integrity of the genome, various mechanisms have evolved to silence TEs. Chromatin modifications, namely DNA methylation and histone modifications, represent two methods of transcriptional silencing of transposable elements. In previous studies it has been shown that methylation of short interspersed nucleotide element (SINE) TEs in the plant and mouse genome can “spread” into flanking sequences.
I chose to investigate this “spreading” phenomenon with respect to endogenous retroviruses (ERVs) which are highly active in the mouse genome. Direct evidence has been provided for ERVs in the mouse genome inducing the spread of repressive chromatin. However, the ability of ERV-induced “spreading” to impact nearby gene expression has not yet been characterized. In my thesis, I provide evidence for repressive chromatin spreading as an infrequent occurrence with the exception of the B3galtl gene where DNA methylation and repressive histone marks spread from a solitary ERV long terminal repeat (LTR) into the CpG island promoter of the gene, which correlates with reduced gene transcription. In most cases, however, I show that CpG islands are unmethylated despite the presence of a nearby methylated ERV. Furthermore, I show examples of differential epigenetic marking of insertions with the 3’LTR of the insertion located closest to the nearby gene exhibiting hypomethylation. In one case in particular, I show an interesting trend between expression of the CdGAP gene and hypomethylation of the nearby 3’LTR.
These results lead to the conclusion that susceptibility to or protection from “spreading” of repressive chromatin marks is a locus-specific event that may be mediated by various factors such as the ERV-gene distance, the presence of a CpG island gene promoter, the chromatin state of the gene promoter, and the expression of the corresponding gene.
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Linderfyhr, Jessica, and Mikaela Malm. "She’s the Boss – HR och kvinnligt chefskap : Hur Human Resources kan arbeta för att främja kvinnorschefskarriärer." Thesis, Högskolan Dalarna, Personal och arbetsliv, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:du-25424.
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Enligt undersökningar som chefsorganisationen Ledarna publicerar årligen finns det en återkommande problematik med att rekrytera unga kvinnor till chefspositioner. Syftet med examensarbetet är att undersöka vad som kan inverka på kvinnors vilja att söka en chefstjänst och att utforma en HR strategi som främjar och motiverar kvinnor att söka chefstjänster. Unga kvinnor kan känna tvekan inför chefskap på grund av känslan av bristande erfarenhet och svårighet med att identifiera sig med den stereotypa chefsnormen. Aspekter av chefskapet som motiverar är möjligheten att kunna påverka, fatta beslut samt personlig utveckling. Att en chef har hög arbetsbelastning är något som omnämns som negativt samtidigt som att utmaningen i chefskapet lockat intervjupersonerna. Fokus på svårigheter med att balansera chefskap och privatliv/familjeliv kan vara en generell förklaring till att färre unga kvinnor väljer en chefskarriär. Chefskapet innebär i många fall en möjlighet till flexibel arbetstid, vilket gynnar balansen mellan arbets- och privatliv. En nyckelfaktor för att kombinera chefskap med familj och barn är en jämställd fördelning av hushållsarbete och ansvar för barnen. Flera av intervjupersonerna har fått sin tjänst genom uppmuntran, något som varit avgörande för att anta chefskapet. För att motivera unga kvinnor till chefstjänster behövs ett engagemang där potentiella kvinnliga chefer upptäcks och uppmuntras till karriär. Arbetet grundas på en kvalitativ ansats med semistrukturerade intervjuer som insamlingsmetod. Resultaten har analyserats utifrån den teoretiska referensram som sammanställts inom fokusområdet. Genomgående följer arbetets uppbyggnad de tematiseringar som baseras på frågeställningarna: Vad är det som gör att unga kvinnor kan tveka inför chefskap? Vad kan motivera unga kvinnor att vilja bli chef? Hur kan arbetslivet som chef kombineras med privatlivet/familjelivet? Hur kan rekrytering förbättras för att motivera unga kvinnor att söka chefstjänster?According to surveys conducted by the organization Ledarna, there is a recurrent problem of recruiting young women to senior positions. The purpose of this essay is to investigate what may affect women's desire to seek a managerial position and to design a HR strategy that promotes and motivates women to seek executive positions. Young women feel doubtful about manager positions because of the feeling of lack of experience and difficulty identifying themselves with the stereotype manage standard. Aspects of the management that motivate are the ability to influence, make decisions and gain personal development. The fact that a manager has a high workload is something that is referred to as negative while the challenge in the manager position attracted the interviewees. Focusing on difficulty in balancing work and private/family life can be an overriding explanation that fewer women choose a managerial career. In many cases, the manager position offers an opportunity for flexible working hours, which benefits the balance between work and private life. A key factor in combining management positions with family and children is an equal distribution of household work and responsibility for the children. Several of the interviewees have gained their position through encouragement, something that was crucial for the manager position. In order to motivate young women into management positions, engagement is needed in which female executive subjects are discovered and encouraged to career. The work is based on a qualitative approach with semi structured interviews as a collection method. The results are analyzed based on the theoretical reference frame compiled within the focus area. Throughout the structure of the work, the thematic approaches are based on the questions: What is it that makes young women doubt about leadership? What can motivate young women to want to become a manager? How can work life as a manager be combined with privacy/family life? How can recruitment be improved to motivate young women to seek executive positions?
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Sewell, Cleveland A. "The relationship between African-Caribbean boys' sub-culture and schooling." Thesis, University of Nottingham, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301859.
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Spackman, Christopher John. "The Boys' Brigade and urban cultures, 1883-1933 : a relationship examined." Thesis, University of Portsmouth, 2016. https://researchportal.port.ac.uk/portal/en/theses/the-boys-brigade-and-urban-cultures-1883--1933(c7a08fd6-2b3e-4d3a-8ae6-d40735f99ff0).html.
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The lived reality of membership of the Boys’ Brigade between 1883 and 1933 has been somewhat neglected in the field of youth histories. Existing histories have focused on the position of founders and headquarters of youth movements, thus neglecting the experience at the local level. Our current understanding of membership of youth movements is based on an interpretation that camping was the most appealing aspect, with historians including John Springhall and Stephen Humphries asserting that this element of the programme was the greatest attraction for most Boys. However, these arguments have not adequately addressed the role of camping within the broader programme of work of youth movements, have afforded insufficient attention to the relationship between the regular sessions and camp, and have overlooked participation figures. This thesis advances our existing understanding by addressing this issue within the specific context of the urban space, providing a unique insight into the lived experience of membership of a Boys’ Brigade Company, whilst offering a comparative aspect often lost in prevailing histories. Through contemporary accounts, statistics from annual reports, oral testimonies, and newspaper articles, this thesis demonstrates that the practical application of the agenda set at the apex of the organisation was applied differently across varied spaces. Additionally, through a more thorough examination of the lived experience of camping, this thesis argues that previous histories have placed too much emphasis on camping as an attraction for young people to join a youth organisation, with the position maintained here that this activity was available to limited numbers from the 1880s to the 1930s, with more Boys experiencing life in this organisation at the weekly classes. This shows that the existing consensus approaches youth movements in broad homogenous terms and overlooks the regional variances in application of the agenda set from headquarters. This is significant to our understanding as it indicates that the urban space was a unique environment where youth movements adapted to local circumstances. Therefore, the Boys’ Brigade is presented in this thesis as a vehicle to improve our understanding of the ways young people interacted in the urban space in late nineteenth and early twentieth century Britain. It offers an indication of the lived experience of membership of a youth movement that is missing from much of the existing histories and provides a clearer indication that the application of the organisation differed across space and place, thus presenting an original contribution to the field of youth histories.
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Price, Eleanor Lisa. "Risk factors for boys' psychologically abusive behaviour in dating relationships." Thesis, University of New Brunswick, 1999. http://hdl.handle.net/1882/382.
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Price, Eleanor Lisa. "Risk factors for boys' psychologically abusive behaviour in dating relationships." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ62177.pdf.
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Molomo, Ntsubise Regina. "Relationship between urinary levels of organophosphate metabolites and pesticide exposures among rural school boys of the Western Cape." Master's thesis, Faculty of Health Sciences, 2021. http://hdl.handle.net/11427/32859.
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Background: Biomonitoring of pesticides is an objective measure of short-term pesticide exposure as it measures possible exposure in the human body. Current evidence on the relationship between demographic, socio-economic and pesticide exposure risk factors and urinary levels of organophosphate (OP) pesticide metabolites among children is generally incomplete and conflicting in some cases. There is therefore a need for further research. Objectives: This study investigated the relationship between socio-economic, demographic and reported pesticide exposure related activities and characteristics in relation to urinary levels of three dialkyl phosphate (DAP) metabolites (diethyl phosphate (DEP), dimethyl phosphate (DMP) and dimethyl triphosphate (DMTP)) among boys living in the rural areas of the Western Cape, South Africa. Methods: This was an analysis of data collected during a cross- sectional study of 183 boys from three agricultural intense areas in the Western Cape of South Africa between April 2007 and March 2008. Measurements included a questionnaire on demographic, socio-economic and pesticide exposure risk factors and analysis of spot urine samples for DAP metabolites. Results: Most of the boys (70%) lived on farms with a median age of 12 years (range: 5.0 - 19.5 years). The median concentrations of DAP, DEP, DMP and DMTP were 68.3 ng/ml (IQR= 27.9; 129.5), 5.5 ng/ml, 32.6 ng/ml and 16.7 ng/ml, respectively. The sum of the three DAP levels wasinversely associated with age. Children older than 14 years had less DAP levels (β = -68.1; 95% CI: -136.8,0.6) than children 9 years and younger. DAP levels also varied significantly with residential area, with the levels highest in Grabouw (apple farming), followed by Hex River Valley (grape farming) (β= -52.1; 95% CI: -97.9, -6.3) then Piketberg (wheat farming) (β= -54.2; 95% CI:-98.8, -9.7). Other weaker and non-significant associations with increased DAP levels were found with increased household income, member of household work with pesticides, living on a farm, drinking water from an open water source and eating crops from the vineyard and or garden. Conclusion: The study found younger age and living in and around an apple and grape farms, to be associated with increased urinary DAP concentrations among the school children provide evidence that younger age and residential area can be associated with increased urinary DAP concentrations among boys. Additionally, there are other household and behavioural characteristics that are associated with elevated urinary DAP levels. Further studies with larger sample sizes and longitudinal designs to improve the statistical power and the associations found are recommended. The study provided more insight to incomplete and inconclusive evidence of previous studies.
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Johnson, Kenneth Earl. "Outcome-based evaluation of interpersonal relationships between teachers and students at the Northwest Florida School for Boys." [Pensacola, Fla.] : University of West Florida, 2007. http://purl.fcla.edu/fcla/etd/WFE0000013.
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Scanlon, Julie. "Listening to boys write : an exploration of the complex relationship between 10 year-old boys' writing practices and their evolving identities." Thesis, Manchester Metropolitan University, 2016. http://e-space.mmu.ac.uk/617792/.
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Being literate has long been considered essential in order for individuals to make their way in the adult world, become productive and contribute to society (Olson, 1994). However, across the western world there appears to be a literacy crisis in the form of a gender gap in which ‘boys do less well than girls’ (Moss, 2007: 13). As a result, boys have been categorised as a problem (Clandinin et al, 2006). Previous research has focused on solving the ‘boy problem’, however, this study offers an alternative perspective in that it explores the complex relationship between pre-adolescent boys’ writing practices and their evolving identities in the domains of school and home. The study draws on sociocultural theories of New Literacy Studies and the concept of ‘Figured Worlds’, as described by Holland et al (1998) in order to consider how three 10 year-old boys participate in the production of themselves as writers and the impact of adult mediation on the boys’ developing identities as writers both at home and in school. This comparative case study is informed by both ethnography and narrative inquiry in order to produce three rich narrative accounts which are centred around the boys’ writing practices both in and out of school. Each narrative offers a unique insight into each boy’s life and their perception of what it means to be a writer through an exploration of their experiences, their ambitions and their relationships with people, technology and curriculum. The narratives are then compared to reveal key themes which highlight the ways in which wider policy and institutional demands influence local practices which in turn impacts on the boys’ identity formation. The significant findings relate to a common theme of relationships. Findings suggest that writing practices are bound to close familial relationships and to each family’s figurative or narrativised identity. Therefore, educators may need to look beyond engaging experiences in the classroom to the space and structures of homes in order to both fully understand boys’ meaning making and to inform their assessments of boys as writers. This extends the current research on early mark making and relationships in pre-school children to this under-explored group of pre-adolescent boys. In addition, the findings also suggest that the way in which schools engage with digital practices will have to be carefully considered if children are to understand digital communications as being writing and not talking. Therefore, the findings offer an alternative perspective to the two great divides in literacy, those being school and home and speaking and writing.
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Underwood, Angela Marie Spano Folkerts Debbie R. "Larvae of Sarcophagidae (Insecta Diptera) and their relationship with the pitcher plants (Sarraceniaceae: Sarracenia) of southeastern U.S. bogs /." Auburn, Ala, 2009. http://hdl.handle.net/10415/1889.
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Hilton, Gillian L. S. "Breaking the macho mould : meeting boys' needs in sex and relationships education." Thesis, Middlesex University, 2003. http://eprints.mdx.ac.uk/13572/.
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The work examines the needs of boys as regards sex education in school. The literature search depicted a situation where boys' needs were being neglected despite the calls from such bodies as the British Medical Association. Literature supports the idea that there is an overemphasis on biology rather than relationships and this, coupled with peer and teacher expectations of masculine behaviour, neither helps boys to cope with relationships nor aids them in their understanding of the needs of others or coping with their own fears and anxieties. The growing problem of early teenage pregnancies and sexually transmitted infections (STIs) had led to comparisons with other countries, which show that England has a severe problem with underage pregnancy and the transmission of STIs. Research was undertaken to investigate the characteristics of sex and relationships education for boys with the object of determining their needs and what types of education would best meet these needs. Investigations took place in eight diverse secondary schools in the south east of England. Questionnaires were issued to boys and girls in the sixth form regarding their experiences of school sex education. In addition students in their first term at university were also asked to complete questionnaires to give a wider scope to the research. Eight co-ordinators of Personal Social and Health Education were interviewed to discover their opinions of sex education in secondary schools at present and whether this was meeting the needs of pupils, especially boys. Research was then conducted to examine alternative methods of delivering sex and relationships education to determine if these strategies could better satisfy boys' needs in this area. These included a student tutor scheme in Prague a teacher training establishment in The Netherlands, an 'agony uncle' who ran a computer help line for boys, a theatre group, two male sex education workers who deliver sex education to boys, a peer education scheme and a Teenage Health Project. Three focus group interviews were carried out with young men of sixteen and seventeen to determine their feelings about their sex education and how it could be improved. In order to assess these diverse schemes a set of criteria was established against which to judge sex education delivery. These criteria were devised from the search of literature, the focus group and questionnaire responses and suggestions from the alternative method respondents and the co-ordinators. The schools' sex education provision and the altemative methodologies were then evaluated against these criteria. Results showed that none of the methods totally met the needs of boys. The analysis was used to determine a new strategy to meet the needs of boys with regard to their sex and relationships education. At the heart of the strategy is a curriculum with a stronger emphasis on relationships, how to cope with and express emotions. The content, methods of delivery, amount of sessions, size of groups and the types of teachers required are also defined.
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Dmytro, Dana. "The role of gender norms in adolescent boys' navigation of romantic relationships." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/59106.
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Focus group discussions were analyzed to gain a better understanding of adolescent boys’ psychosocial processes of navigating their romantic relationships. In particular, the role of gender norms in boys’ navigation of romantic relationships was explored. Using grounded theory methodology, focused discussions were held with 23 boys in Grades 9 through 12 at high schools in an urban school district. The central phenomenon identified to be occurring during these participants’ relationship navigation was getting experienced in dating. Six other categories were identified: initiating dating relationships, benefiting/”gaining” from relationships, communication, managing relationship issues, relationship breakdown, and disengaging from dating. Contextual conditions were also found to be influencing participants’ relationship navigation: struggling to be confident, social/digital media culture, peers’ perceptions, parental expectations, multicultural context, female gender stereotypes, and finally, masculine gender norms. The significance of the findings in relation to boys’ relationship navigation, social and emotional learning, the development of psycho-educational interventions, and the implications for school psychologists are discussed.Education, Faculty of
Graduate
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Smith, Dewain E. "Building boys into men| The relationship between discipline and spirituality in high school males." Thesis, Capella University, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3564233.
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The purpose of this qualitative, ethnographic study was to discover whether a relationship exists between discipline and spirituality in high school males. This study is important because it will apply traditional reasons for Catholics to send their children to private Catholic schools, to the disciplined curricular rigor and spiritual environment offered at one single-gender, military and college preparatory, Catholic high school. This qualitative, ethnographic study investigated the relationship between discipline and spirituality, and the researcher was a participant-observer. The participants were stakeholders, ranging from 18 to 65 years of age. The following data was used for purposes of triangulation: interviews with students, parents, alumni, teachers (faculty group), and observations of teacher practice; a preference survey of alumni; and a comparative study of randomly selected blind (unnamed) student data, from JROTC and Administration records. These data were collected and analyzed to provide validity and integrity to interpreted qualitative data, and added a quantitative component to the study. The researcher's analysis considered the data collected to identify the themes that emerged, and to find the voice of the stakeholder community. The study revealed 8 broad sub-themes that were paired as follows: (a) choice and culture; (b) brotherhood and camaraderie; (c) acculturation and enjoyment; and (d) Catholic and Mass. From the sub-theme pairs 4 overarching major themes emerged. They were choice, brotherhood, acculturation, and Catholic. These major themes represent the heart of the investigation. The study revealed that a relationship does exist between discipline and spirituality. This study contributes to the academic discussion, regarding single-gender education, and a positive learning environment. This study presents an invitation to future research.
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Frontiera, Joe. "The relationship between leadership, efficacy belief, and performance among boys' high school basketball players." Morgantown, W. Va. : [West Virginia University Libraries], 2006. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4557.
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Bivens, Mark. "The relationship between attention-deficit/hyperactivity disorder and perceived locus of control in boys." Curtin University of Technology, Faculty of Education, 2000. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=12016.
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The research examines the relationship between the two variables Attention- Deficit/Hyperactivity Disorder (A-D/HD) and Locus of Control in boys identified with A- D/HD.The major issues addressed are: the extent to which attentional deficit predicts external Locus of Control and the effect of a cognitive-behavioural intervention on boys with A- D/HD and a highly externalised Locus of Control. Reducing the externality of Locus of Control is seen as an innovative means of addressing some behavioural aspects of A-D/HD.The study involved 77 A-D/HD boys with A-D/HD and 23 boys who were not A-D/HD, but who demonstrated similar levels of disruptive behaviours, from schools in Western Australia. Australian norms were established for the Locus of Control instrument (CNS-IE) using 300 male classmates of the participants.Each boy was assessed by parents and teachers on established measures of A-D/HD (the Child Behavior Checklist (CBCL) and the Attention Deficit Disorders Evaluation Scale (ADDES)). The boys completed the CNS-IE both before and after the intervention. The boys with A-D/HD were medicated with Dexamphetamine or Ritalin, as prescribed by an appropriate medical practitioner.The association of A-D/HD diagnostic subtypes, (Predominantly Inattentive Type, Predominantly Hyperactive Type, Combined Type) with Locus of Control was also investigated.The results demonstrate that a significant (p < 0.001) correlation exists between attention deficit (assessed by the two parallel measures, CBCL and ADDES) and Locus of Control. The Locus of Control of boys with A-D/HD was significantly (p < 0.001) more external than that of the non-A-D/HD boys. This finding held true for each of the three A-D/HD subtypes when they were compared to the non-A-D/HD group.Participation in the cognitive behavioural intervention (the Stop, Think, Do program) significantly (p < 0.001) reduced the level ++of externality of Locus of Control in all groups of subjects.The research also examined the relationship between parents and teachers ratings of the same individual's behaviour. Ratings were found to be highly consistent between both groups. Parent ratings of inattention appear to be particularly salient both in identifying boys with an associated external Locus of Control and as an indicator of A-D/HD.The results of the research support the use of appropriate cognitive behavioural interventions in addressing self-regulation and responsibility, the central issues put forward in the Behavioural Disinhibition model of A-D/HD.Implications for the management of A-D/HD in the long term are also addressed. A multi- modal model involving medication and two stages of cognitive-behavioural intervention is recommended, where a cognitive behavioural intervention is used initially to develop a more internal Locus of Control, this being followed by a reframing program to sustain and develop more adaptive perceptions and behaviours.
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Thornburgh, Allison L. "First Bosses' Primary Early Career Mentor Influence on Women Leaders in the Retail Industry." Ohio University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1345688828.
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Fridell, Sari R. "Sex-typed play behavior and peer relationships of boys with gender identity disorder." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ63664.pdf.
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Carter, Charlotte Louise. "Human rights in secondary education : relationships and identities within an all boys' school." Thesis, University of Birmingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289601.
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Vieville, Pascal. "Influence des paramètres architecturaux sur le comportement viscoélastique du matériau bois à ses différentes échelles d'hétérogénéité." Vandoeuvre-les-Nancy, INPL, 1992. http://docnum.univ-lorraine.fr/public/INPL_T_1992_VIEVILLE_P.pdf.
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Le matériau bois est composite alvéolaire constitué de plusieurs bio polymères dont le comportement viscoélastique macroscopique est le produit de comportements locaux situés à trois échelles d'hétérogénéité distinctes: le tissu élémentaire, le tissu constitutif du cerne et du rayon ligneux, le bois massif. Pour chacune de ces échelles, il est possible de dégager des paramètres géométriques variables dont on peut apprécier l'influence sur les caractéristiques viscoélastiques locales du matériau grâce à une méthode de calcul des propriétés effectives: la méthode autocohérente
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MacKie, Leila. "The relationship between language skills, social cognition and externalising behaviour in primary school aged boys." Thesis, Queen Margaret University, 2010. https://eresearch.qmu.ac.uk/handle/20.500.12289/7451.
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There is evidence of a high incidence of language difficulties (LD) amongst boys with externalising behaviour (EB); however we still have little understanding about why they co-occur. This 3 part study investigates aspects of this relationship framed within a biopsychosocial model and with a focus on pragmatic language skills and social cognition. Firstly, this study seeks to replicate recent research that has indicated a close association between pragmatic language skills and EB. It is the first study to consider the strength of this association while controlling for other variables known to commonly co-occur with LD and EB: aspects of the child’s ability (word decoding and nonverbal cognitive skills), and aspect of their environment (parenting stress, maternal education and family set up). Secondly, this study furthers our understanding of the social cognitive and friendship skills of boys with LD, in both areas through investigating reasons for variance in ability. A better understanding of an LD population feeds into our understanding of EB due to the high proportion of boys with EB who have coexisting LD. Thirdly, this study measures social cognition of boys EB while accounting for the role of LD, thus investigating whether difficulty with these tests is associated with the high rate of LD in this population. Previous studies have not adequately considered this. Method: Boys aged 8 to 11 years receiving additional support in school were assessed for LD and EB and two groups (not mutually exclusive) were identified: boys with LD (n=31) and boys with EB (n=35). A control group of typically developing boys matched for age and SES were also identified (n=42). For part one, participants completed assessments of language skills, word decoding and non-verbal cognitive ability. Teachers completed a checklist to provide a measure of pragmatic language skills. Parents completed questionnaires to provide measures of parenting stress, family set-up and maternal education. For the second and third part of the study participants’ social cognition was assessed and parent and teachers completed a checklist for measurement of emotional and behavioural difficulties including friendship skills. Results and discussion: In the first part of this study, all variables measured were found to be significantly associated with EB, as would be expected within a biopsychosocial model in which many factors interact with each other in the development of EB. However, particularly close associations were found between pragmatic language skills and EB (replicating previous research in this area), followed by language skills. This indicates a close and specific association between communication skills and EB, even when other closely associated variables are accounted for. In part two, amongst boys with LD, different social cognition assessments were found to be associated with different aspects of communication skills. One was most closely associated with structural (particularly expressive) language and the other two with pragmatic language. This indicates that they are tapping different constructs and highlights the difficulty using a proxy to give an indicator of social cognition; it is not easy to assess. Variability in friendship skills of boys with LD was not associated with any aspect of communication skills. Significant correlations were found with two of the social cognition test scores only. This is at variance with research indicating a link between friendship and receptive language skills. In part 3, the EB group scored significantly lower than the Control group in tests of social cognition, however EB was not found to be linked with social cognition score. Only boys with LD (with or without EB) scored significantly lower than the Control group. This has implications for previous research into the social cognition of boys with EB which has not fully considered the high proportion with LD and the extent this may be contributing to their low social cognition scores. Implications for practice and future research are discussed.
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Goldberg, Scott J. "The relationship between English (l1) and Hebrew (l2) reading and externalizing behavior amongst Orthodox Jewish boys /." Ann Arbor, Mich. : Xerox University Microfilms, 2004. http://wwwlib.umi.com/dissertations/preview/3110997.
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Thesis (Ph.D.) -- New York University, 2004. Xerox of original typescript, Ph.D thesis, The Steinhardt School of Education, New York University 2004.Publication no. AAT 3110997 New York University.
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Williams, M. D. "A study of the inter-relationships between immunosuppression, treatment and infective complications in haemophilic boys." Thesis, University of Liverpool, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381304.
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Weggelaar, Cristy Lauren. ""It's All Because I Like the Person That's Teaching Me": Masculinities, Engagement, and Caring Relationships in Secondary Schools." PDXScholar, 2019. https://pdxscholar.library.pdx.edu/open_access_etds/5007.
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U.S. schools face a well-documented gender gap within some important educational and social indicators. In the United States, boys and young men are significantly more likely than girls and young women to be diagnosed with a learning disability, leave high school without a diploma, receive failing grades in core classes, and be suspended or expelled from school. This study uses an interpretive research framework to investigate the relationship between this gender gap in education and constructions of masculinity, social and cultural capital, agency, caring and resistance in secondary schools. Data collected through interviews with young men who engaged in acts of resistance against schooling yielded three major findings. First, some acts of resistance provided the participants with a means to ease the tedium and stress of academic work and enhance social capital among their male peers. Second, some acts of resistance provided participants with a means to regain personal agency when they felt either marginalized by an oppressive system or generally rejected, ignored, or alienated from the formal schooling environment. Finally, participants expressed an appreciation for authentic relationships with their teachers and stated that they were less likely to engage in acts of resistance with teachers who nurtured authentic caring relationships in the classroom.
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Monate, Pearl Naledi. "The relationship between urinary organophosphate pesticide residues and reproductive development among boys living in the rural Western Cape." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29591.
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Background: Many contemporary agricultural pesticides are hormonally active, but few previous studies have investigated their effect on the reproductive health and growth of pubertal boys. A previous analysis found significant differences in serum reproductive hormone levels and lower anthropometric measurements as well as non-significant lower sexual maturity ratings and testicular sizes in farm boys compared to non-farm boys from the rural Western Cape in South Africa. Methodology: This analysis included 183 out of 269 school boys residing on farms and neighbouring nonfarming areas who provided urine samples in a cross-sectional study. Measurements included a questionnaire, clinical assessment of sexual maturity development (SMD), anthropometric measurements (height, weight and body mass index (BMI)), serum reproductive hormones (including luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone and oestradiol (E2)) and urinary levels of 3 dialkyl phosphates (organophosphate pesticide metabolites) including di-ethyl, di-methyl and di-methyl triphosphate (DEP, DMP and DMTP). Results: The median (interquartile range) of age and sum dialkyl phosphates of the school boys was 12 years (9-13 years) and 68.3 ng/mL (27.9-129.5 ng/mL) respectively. There were consistent, mostly non-significant associations with some dose response relationships between urinary levels of dialkyl phosphates and adverse effects on outcomes including SMD, serum reproductive hormones and anthropometric development. The strongest results included a strong positive association and dose response found between serum oestradiol > the 50th percentile and quartiles DMTP (odd ratio and confidence interval for highest and lowest quartile: 7.4; 1.7-32.4) and between BMI <50th percentile and quartiles of DMTP (odd ratio and confidence interval for highest and lowest quartile: 3.2; 1.2-9.0). Conclusion: The results provide some preliminary evidence that organophosphate pesticides exposure could alter the reproductive hormone levels and adversely affect the body size of school boys. There was also lack of evidence of other adverse effects on reproductive development. These findings require further investigation in a larger longitudinal study with seasonal bio-monitoring for pesticides.
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Holland, John Michael. "Successful Emergent Literacy Head Start Teachers of Urban African American Boys Living in Poverty." VCU Scholars Compass, 2012. http://scholarscompass.vcu.edu/etd/3147.
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This integrated methods study used a sequential explanatory design to explore the culturally relevant teaching beliefs of successful emergent literacy Head Start teachers of urban African American boys living in poverty. The study utilized emergent literacy gain scores as a measure of success, a survey of culturally relevant teaching beliefs to describe variation in beliefs within the sample, and two rounds of interviews to explore the context of teacher agency with urban African American boys living in poverty. The four teachers interviewed expressed culturally relevant beliefs integral to their teaching practices. These beliefs were conveyed through descriptions of relationships with parents in and out of the classroom, through of the conditions and challenges of poverty in students' and parents' lives, and through close relationships with parents. The effect of conducting home visits on teachers' identities and the influence of the setting of Head Start on teachers' beliefs and agency were emergent themes in the interviews. The participants used language that seemed to indicate culturally relevant and warm demander approaches to understanding the relationship between student behavior and student engagement and in descriptions of the relationships with parents. The value of teachers' relationships with their students' parents was the most pronounced aspect of successful teaching in Head Start as expressed by the participants. The process of communication among parents, students, and teachers was described as important to student learning. The participants' expressed a variety of approaches to how they understood student behavior, boys' social emotional development, and classroom practices. These Head Start teachers described boys as more active than girls, as more aggressive than girls, and sometimes more challenged to express strong emotions with language than girls. This study provides some insight into the role that culturally relevant teaching beliefs play in Head Start teachers' successful
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Liu, Suk-ching Elaine, and 廖淑貞. "Parental social support and young adolescents running away from home." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31240616.
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Betancourt, Maria Camila Ceballos. "Acesso à informação sobre boas práticas de bem-estar animal : efeitos sobre a qualidade do manejo, temperamento e bem-estar de bovinos de corte /." Jaboticabal, 2017. http://hdl.handle.net/11449/151942.
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Orientador: Mateus José Rodrigues Paranhos da CostaCoorientador: Aline Cristina Sant'Anna
Resumo: O objetivo desta tese foi avaliar os efeitos do acesso de vaqueiros à informação sobre boas práticas de manejo de gado de corte na a qualidade do manejo, o temperamento e o bem-estar dos bovinos. Os objetivos específicos foram: 1) Contribuir para uma maior compreensão da relação entre a interação humano-animal, temperamento, resposta ao estresse e performance reprodutiva de novilhas nelore submetidas ao protocolo de inseminação artificial em tempo fixo; 2) Avaliar o potencial impacto do treinamento de vaqueiros em boas práticas de manejo sobre as atitudes e a qualidade de manejo dos mesmos e o bem-estar do gado; 3) Comparar fazendas onde todos os vaqueiros foram treinados com fazendas onde alguns foram treinados e fazendas onde ninguém foi treinado e; 4) Estudar se a qualidade do manejo do gado deteriora ao longo de um dia de trabalho. Para o primeiro objetivo específico, um total de 571 novilhas foram usadas para avaliar dois indicadores de temperamento (a velocidade de saída - VS e o escore composto de reatividade REA), cinco indicadores de interação humano animal (manejo negativo - MN, acidentes - ACIDENTES, defecação e micção - DEF-MIC, comportamentos indesejados - CI e tempo de entrada - TE) e a sujidade na região perineal - SUJIDADE. Todos esses indicadores foram avaliados no dia d0, d7 e d11 de um protocolo de inseminação a tempo fixo. Adicionalmente, dois indicadores de estresse (cortisol - CORT e relação neutrófilo: linfócito - N:L) foram avaliados em uma sub-amostra... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The objective of this thesis was to assess the effects of the stockpeople access to information about good beef cattle handling practices on the quality of handling, cattle temperament and welfare. The specific objectives were: 1) To further contribute to the understanding of the relationships between human-animal interactions, temperament, stress response, and reproductive performance of Nellore heifers submitted to a FTAI protocol; 2) To evaluate the potential impacts of handling skills training on good practices of cattle handling on stockpeople' attitudes and behavior, and cattle welfare; 3) To compare farms where all stockpeople were trained, to farms where only some where trained, and farms where none where trained and, 4) To study whether the quality of cattle handling deteriorates as the working day time passes. For the first specific objective, a sample of 571 heifers was used to assess two temperament traits (flight speed - FS and the composite reactivity score - RS), five human-animal interaction traits (negative handling - NH, Accidents - ACCIDENT, Defecation-urination - DEF-URI, Undesirable behavior - UB and Entrance time - ET), and perineal region dirtiness - DIRTINESS. All variables were assessed on d0, d7 and d11 of a FTAI protocol. Additionally, two physiological indicators of stress (cortisol - CORT and neutrophil:lymphocyte ratio - N:L) were recorded in a subsample of 99 heifers on d0 and d11. The occurrence of NH was associated with the occurrence of ACCID... (Complete abstract click electronic access below)
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Kerner, Charlotte Lynn. "Relationships between body image, motivation and physical education (PE) experiences in 13-14 year old boys and girls." Thesis, University of Bedfordshire, 2013. http://hdl.handle.net/10547/315360.
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Research has established that body image disturbance is associated with a number of negative physical and psychological health outcomes. It is recognised that body image is subject to situational variability, yet to date, research seems to have overlooked the explicit exploration of the stability of the construct within physical education. With this in mind the overarching aim of this thesis was to explore relationships between body image, perceptions of competence and motivation, with specific attention paid to the influence of the physical education environment upon year nine boys and girls situational body satisfaction. Secondly, the thesis explores the role that these three psycho-social constructs play in transfer of learning. The design of the research was a correlational, repeated measures study conducted across two time points, combined with focus group sessions. Quantitative data collection at time point one consisted of 620 pupils from 37 year 9 physical education classes. Time point two consisted of 461 pupils from 38 physical education classes. At both quantitative time points students responded to a questionnaire package which explored perceptions of competence towards physical education, motivation for physical education and aspects of trait and state body image. Participants at time point one also provided demographic information. Additionally, 159 pupils at time point one underwent anthropometric assessments of body fat and BMI. The findings from the thesis identify that 71%-80% of year 9 boys and girls are dissatisfied with their current body size. It was identified that the majority of variance in situational body satisfaction within physical education can be attributed to factors operating at the pupil and time level, with a smaller yet significant proportion of variance being attributed to between-class factors. Lesson content did not significantly predict variations in body satisfaction scores within physical education and evidence from the focus group sessions suggest that classroom entry factors such as the changing rooms maybe more influential that factors operating within the lesson itself. Results revealed higher levels of body satisfaction within physical education are associated with higher perceptions of competence within physical education, higher levels of autonomous towards physical education, higher transfer of learning scores and lower amotivation towards physical education scores. Collectively, the results of the thesis identify the prevalence of body dissatisfaction in 13-14 year old boys and girls and the potential implications negative body satisfaction can have for experiences of physical education. Findings of the thesis warrant further investigation of how the psychological variables explored relate to further contextual and pedagogical factors.
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Sylvester, Frederick James. "At risk youth: the experiences of adolescent boys with absent fathers." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/4121.
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Thesis (MEdPsych (Educational Psychology))--University of Stellenbosch, 2010.ENGLISH ABSTRACT: The single-parent, female-headed household is a global phenomenon. In a patriarchal society such as South Africa, the absence of a father figure in the family place mothers in the unenviable position of having to play a double role, namely that of mother as well as the head of the family. The role of absent fathers in the at-riskness of adolescent boys is under researched in South Africa. The aim of this study was to explore and describe the perceptions and experiences of ten adolescent boys who are growing up in father absent homes. The participants were from a low socio-economic area of the Western Cape, and high school pupils who were purposively selected from Grades 8, 9 and 10. A qualitative research methodology was used and data were collected by means of semi-structured interviews, a focus group discussion and the construction of collages. The findings showed that adolescent boys face many challenges in their development when they grow up without a strong male role model. These ten adolescents seemed to struggle with discipline issues at school as well as at home. They are at a vulnerable age, and at risk of making decisions that would be devastating to their futures.
AFRIKAANSE OPSOMMING: Die enkelouer, vrou-as-hoof huishouding is ‟n globale fenomeen. In ‟n patriargale samelewing soos Suid-Afrika plaas die afwesigheid van ‟n vader in die gesin ma‟s in ‟n situasie waar hulle dubbele rolle moet vertolk, naamlik as ma sowel as hoof van die gesin. Die rol van die afwesige pa in die bevordering van riskantheid by adolessente seuns is nog nie voldoende nagevors nie. Die doel van hierdie studie was om die persepsies en ervaringe van tien adolessente seuns uit huise met afwesige vaders in te verken en te beskryf. Die deelnemers was uit ‟n lae sosio-ekonomiese area van die Wes-Kaap en doelgerig uit Grade 8, 9 en 10 geselekteer. ‟n Kwalitatiewe navorsingsmetodologie is gebruik en data is deur middel van semi-gestruktureerde onderhoude, ‟n fokusgroepgesprek en die konstruksie van ‟n kollage ingesamel. Die bevindinge toon dat adolessente seuns baie uitdaging ervaar tydens hul ontwikkelingssfase wanneer hulle opgroei sonder ‟n sterk manlike rolmodel. Die tien adolessente sukkel met dissipline by die skool sowel as tuis. Hulle is ‟n brose ouderdom en loop die gevaar om besluite te neem wat hulle toekoms kan vernietig.
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McGoran, Neil Alexander, and res cand@acu edu au. "Making “Magic”: an exploration of the relationship between teacher leadership and boys’ academic motivation in the Year 8 classroom at a Catholic school." Australian Catholic University. School of Educational Leadership, 2005. http://dlibrary.acu.edu.au/digitaltheses/public/adt-acuvp85.09042006.
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This research explored the understandings and perceptions of teacher leadership in the Year 8 classroom, as expressed by teachers and students at a Catholic school, and the relationship between this leadership and boys’ academic motivation. The researcher assumed that the classroom is an organisation (Cheng, 1994) where all teachers, perhaps even unknowingly (Crowther, 1996), exercise leadership and, furthermore, that this leadership results in positively influencing boys’ willingness to learn. The research was targeted at Year 8, the first year of high school in South Australia, because academic motivation is considered most problematic during and after transition into high school (Maehr & Midgley, 1991). The research was interpretivist, with symbolic interactionism as the theoretical perspective. The methodology adopted was case study, and data were collected using: a) Focus group interviews with eight members of the Year 8 ‘core’ teaching team on issues pertaining to teacher leadership in the classroom and how this positively influences boys’ academic motivation. b) A survey questionnaire about academic motivation, distributed to thirty-nine specially identified Year 8 students. c) Interviews with five key Year 8 student informants about teacher leadership and its impact on boys’ academic motivation. Data were analysed using a “general analytic strategy” (Yin, 1994, p.102), which included the adoption of a method of “successive approximation” (Neumann, 1997, p.427). Five categories of teacher leadership in the Year 8 classroom were identified: service; authenticity; transformation; empowerment; and community. The research also established that each category involves an array of qualities that help teacher leaders strengthen relationships in the classroom, and a set of actions that enable teacher leaders to help boys complete classroom tasks. Further, results indicate that by strengthening relationships and supporting boys to complete tasks, teacher leaders positively influence boys’ academic motivation. In addition, the research presents a framework for understanding and discussing the relationship between teacher leadership and boys’ academic motivation. This framework draws attention to the relational qualities and task specific strategies in each category of classroom leadership that positively influence boys’ academic motivation.
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Gekas, Paulo Demetre. "Correlações entre desafinado e moon dreams: uma análise dos processos lineares e harmônicos." Universidade do Estado de Santa Catarina, 2005. http://tede.udesc.br/handle/handle/2183.
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It is noticed, in literature, and about Brazilian popular music the affirmative comments about the similarity existent between Bossa Nova and Cool Jazz that may be a result from the possible adoption of Cool Jazz elements by Bossa Nova composers. This research has its origin in the need to locate, via musical analysis, co-relationships between representative works from the Cool Jazz and Bossa Nova. Two arrangements works, one of each kind, were selected, nominated by that literature, as representative: Desafinado from the composer Antônio Carlos Jobim in partnership with Newton Mendonça with arrangements by Jobim and Moom Dreams by Chummy MacGregor in partnership with Johnny Mercer with arrangements by Gil Evans. For the selection of those arrangements three aspects were taken into consideration: representation of the works, the originality and the notoriety of the arrangement. From Arnold Schoenberg and Almir Chediak s perspective, aspects concerning the melodic stratum were collected and related, via the analysis of the linear and harmonic processes, aspects concerning the melodic stratum such as basic motive, melodic variation procedures and motivic traces. And the harmonic processes including the polyphonic and homophonic resources, cadences, modal loan chords, superstructure chords, interval relationship between bass line and melody, modulations, auxiliary notes. As a result of the hereto made analysis it was noticed the existence of co-relationships between those works regarding the motivic traces, motivic variation procedures, cadences, superstructure chords, interval relationship between bass line and melody, modal loan chords and auxiliary notes. The survey of those aspects allowed, in a restrict way to those arrangements, to profoundly study and confirm some of the affirmative comments existent in literature concerning the common characteristics to those musical styles
Na literatura sobre música popular brasileira verifica-se a reiterada afirmação a respeito de uma possível assimilação de elementos do Cool Jazz por compositores da Bossa Nova. Esta pesquisatem sua origem na necessidade de localizar, por meio da análise musical, correlações entre obras representativas dos estilos Cool Jazz e Bossa Nova. Foram selecionados dois arranjos de obras indicadas pela literatura como representativas, sendo um de cada estilo: Desafinado do compositor Antônio Carlos Jobim em parceria com Newton Mendonça, arranjada por Jobim e Moon Dreams, de Chummy MacGregor em parceria com Johnny Mercer, arranjada por Gil Evans. Para a escolha desses arranjos foram levados em consideração três aspectos: a representatividade das obras, a originalidade e notoriedade do arranjo. Dentro da perspectiva de Arnold Schoenberg e de Almir Chediak foram levantados e relacionados, através da análise de processos lineares e harmônicos, aspectos concernentes ao estrato melódico tais como: motivo básico, procedimentos de variação melódica e traços motívicos e aos processos harmônicos, entre eles: recursos polifônicos e homofônicos, cadências, acordes de empréstimo modal, acordes de superestrutura, relação intervalar entre linha do baixo e melodia, modulações e notas auxiliares. Como resultado das análises aqui realizadas observou-se a existência de correlações entre as obras no que diz respeito aos traços motívicos, procedimentos de variação motívica, cadências, acordes de superestrutura, relação intervalar entre linha do baixo e melodia, acordes de empréstimo modal e notas auxiliares.
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Chan, Yuk-yee Catherine. "Relationship between intellectual functioning, school adjustment, academic achievement and delinquency among male junior secondaryschool pupils." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1985. http://hub.hku.hk/bib/B2978248x.
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Hoppen, Carolina. "Efeitos do estresse biótico na expressão de terpenos em plantas: Varronia curassavica Jacq. and Pistacia palaestina Boiss." Universidade Tecnológica Federal do Paraná, 2018. http://repositorio.utfpr.edu.br/jspui/handle/1/3260.
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Conselho Nacional do Desenvolvimento Científico e Tecnológico (CNPq)Os terpenos constituem a classe de produtos naturais com maior diversidade química e estrutural, estando associados ao metabolismo das plantas e às interações destas com outros organismos. Estes compostos, as enzimas que os sintetizam e as plantas que os produzem são amplamente estudados em diferentes aspectos. Para melhor compreensão da expressão de terpenos em plantas sob estresse biótico, as espécies Varronia curassavica e Pistacia palaestina foram estudadas neste trabalho. Folhas de V. curassavica contém óleo essencial rico em sesquiterpenos com propriedades anti-inflamatórias, especialmente α-humuleno and β-cariofileno. O objetivo deste estudo foi avaliar as respostas do seu metabolismo em função da aplicação de dois eliciadores naturais no conteúdo de sesquiterpenos de V. curassavica. Para isso, as plantas receberam a aplicação de acibenzolar-S-metil (500 mg L-1), 1,6 β-D-glucano obtido a partir de Lasiodiplodia theobromae (50 mg L-1) e água destilada como controle, sendo realizada as avaliações de trocas gasosas, atividade das enzimas fenilalanina amônia-liase, superóxido dismutase, peroxidase e catalase, bem como a análise química do óleo essencial. Acibenzolar-S-metílico reduziu significativamente a taxa líquida de assimilação de carbono e a concentração intercelular de CO2, enquanto que 1,6 β-D-glucano reduziu significativamente apenas a concentração intercelular de CO2. O maior rendimento de óleo essencial (0.819%) foi obtido em plantas eliciadas por 1,6 β-D-glucano. As proporções relativas e a quantidade de α-humuleno e β-cariofileno não diferiram entre os tratamentos, porém os eliciadores aumentaram significativamente a atividade da enzima guaiacol peroxidase. Os terpenos estão presentes nas folhas e galhas de Pistacia palaestina. Apesar do mecanismo de desenvolvimento das galhas ainda não ter sido completamente elucidado, sabe-se que espécies de afídeos como Baizongia pistaciae L. manipulam anatomicamente, fisiologicamente e quimicamente as plantas hospedeiras em seu benefício. Por este motivo, o isolamento e a caracterização funcional dos genes que codificam terpeno sintases em galhas induzidas por B. pistaciae, bem como sua expressão relativa por RT-qPCR em folhas e galhas de P. palaestina foram os objetivos deste trabalho. A expressão heteróloga foi realizada em E. coli pLYS-BL21, sendo as reações enzimáticas feitas com proteínas purificadas e usando geranil difosfato (GPP) ou farnesil difosfato (FPP) para testar a atividade das enzimas como mono- e sesquiterpeno sintases, respectivamente. Para o experimento de RT-qPCR, foi selecionado um gene referência entre actina, ciclofilina, fosfoglicerato quinase, RNA polimerase II, α-tubulina e ubiquitina. Em seguida, realizaram-se reações com as terpeno sintases para avaliar as diferenças nos níveis de expressão em folhas não colonizadas e galhas. Foram isoladas e caracterizadas duas monoterpeno sintases (PpTPS281 e PpTPS809) e uma sesquiterpeno sintase (PpTPS232) em P. palaestina. PpTPS281 produziu exclusivamente D-limoneno a partir de GPP, enquanto PpTPS809 produziu vários monoterpenos a partir de GPP e PpTPS232 catalisou a formação de diferentes sesquiterpenos a partir de FPP. Os resultados da RT-qPCR mostraram que o gene actina é o mais apropriado para ser usado na comparação de expressão de genes de folhas não colonizadas e galhas induzidas por B. pistaciae. Os níveis de expressão dos três genes foram significativamente aumentados em galhas (de 2,21- a 96.5-vezes), quando comparados com folhas.
Terpenes are a large and diverse class of natural products, being associated with plant metabolism and interactions with other organisms. Nowadays compounds and enzymes of the terpenes pathway in plants are widely studied in different aspects. Varronia curassavica and Pistacia palaestina were the selected species to study the biotic stress effects on terpenoids expressions. Leaves of V. curassavica are the commercial source α-humulene and β-caryophyllene, sesquiterpenes with anti-inflammatory properties. The objective of this study was to evaluate the effect of two natural elicitors on the sesquiterpene content of V. curassavica. Thus, field grown plants received the application of acibenzolar-S-methyl (500 mg L-1), 1,6 -D-glucan obtained from Lasiodiplodia theobromae (50 mg L-1) and distilled water as a control. Gas exchange rate, terpene enzymes such as phenylalanine ammonia-lyase, superoxide dismutase, guaiacol peroxidase and catalase activity and essential oil content in leaves were measured. Acibenzolar-S-methyl reduced significantly the net carbon assimilation rate and the intercellular CO2 concentration, while1,6 -D-glucan reduced significantly only the intercellular CO2 concentration. The highest essential oil yield (0.819%) was obtained in plants elicited with 1,6 -D-glucan. The content of α-humulene and β-caryophyllene did not differ among treatments however the elicitors provided a significant increase in guaiacol peroxidase activity. Terpenes are present in Pistacia palaestina in leaves and in horn-shaped galls. The mechanism of gall development remains unknown, however it is clear Baizongia pistaciae L., an aphid species, manipulates their hosts anatomy, physiology, and chemistry for their own benefit. To isolate and functional characterize terpene synthase genes from galls induced by B. pistaciae as well as their gene relative expression by RT-qPCR in leaves and galls of P. palestina were the aims of this study. The heterologous expression was performed in E. coli pLYS-BL21 cells, being enzymatic assay reactions made with the purified proteins using geranyl diphosphate (GPP) or farnesyl diphosphate (FPP) to test for possible mono- and sesquiterpene synthase activity, respectively. For relative real-time PCR, it was selected an appropriate reference gene between actin, cyclophilin, phosphoglycerate kinase, RNA polymerase II, α-tubulin and ubiquitin. After selection, it was performed reactions with terpene synthases genes to evaluate differences in expression levels in P. palaestina non-colonized leaves and galls. Two monoterpene synthases (PpTPS281 and PpTPS809) and one sesquiterpene synthase (PpTPS232) were isolated and characterized in P. palaestina. PpTPS281 produced exclusively D-limonene from GPP, while PpTPS809 produced several monoterpenes from GPP and PpTPS232 catalyzed the formation of different sesquiterpenes from FPP. Real-time PCR results showed that actin is the most proper gene to be used for genes expression studies between non-colonized P. palaestina leaves and galls induced by B. pistaciae. The levels of expression of the genes were significantly upregulated in galls (from 2,21- to 96.5-fold) when compared to leaves.
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Pilfalk, Marie. "Att organisera för pojkars lärande : En studie av pojkars syn på framgångsfaktorer för lärande." Thesis, Karlstads universitet, Institutionen för pedagogiska studier (from 2013), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-73618.
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This Master essay has examined boys´own view of success factors for learning. The attended school is organized with pupils from 6-16 years old. It is a school in West Sweden, which has good results among boys leaving school, the difference from the country´s results are significant. The purpose of the study has been to find out from an organizational and pedagogical perspective which success factors therer are for boys´ learning. The study has a qualitative approach and semi structured interviews were conducted in groups of two or three pupils (boys) in grade nine. The method for the interviews is called Perception Map (Sherp, 2018) and has been completed like a dialogue in the group. What emerged out of the interviews are analyzed by using three research questions: Which are boys´own view of success factors at the current school? How do the boys connect the success to the school´s profile? To what extent are the boys´view of success factors characterized by quality education? In the results of the study it can be concluded that the two perspectives are interdependent and that the basic conditions are a factor of great importance. The small school and the small classes provide the conditions for the teachers to have time to meet each of the students and get to know them and everyone´s needs. These meetings are the basis of a good relationship that can be created between students and teachers, and the good relationship creates security and a calm environment. To sum up, this together provides the conditions for teaching and learning. What then happens in the classroom is dependent on the teacher´s competence and ambition to motivate, interest and catch the students´ attention. It also means that the school´s culture is characteristic of the values that prevail in the boy´s group and the prerequisite for whether a study culture is created instead of an anti-study or anti-effort culture.Sammanfattning Denna magisteruppsats har undersökt pojkars egen syn på vad som är framgångsfaktorer för lärande. Undersökningen är gjord i en F-9-skola i västra Sverige bland pojkarna i åk nio utifrån att skolan har signifikant högre genomsnittlig meritpoäng än rikssnittet för samma grupp. Syftet med studien har varit att utifrån ett organisatorisk och pedagogiskt perspektiv få fram vilka framgångsfaktorerna är för pojkars lärande. Studien har både en kvalitativ och en kvantitativ ansats, där halvstrukturerade intervjuer har gjorts i grupp om två till tre elever. Intervjumetoden har varit föreställningskarta enligt Scherp (2018) och eftersom den gjorts i grupp har den karaktäriserats som ett lärande samtal. Nyckelord och utsagor har sedan analyserats utifrån de tre frågeställningarna, varav den sista även analyserats utifrån Håkansson & Sundbergs (2018) sju riktningsgivare för en kvalitativt god undervisning: Vilken är pojkarnas syn på skolans framgångsfaktorer? På vilket sätt kopplar pojkarna framgången till skolans profil? I vilken utsträckning kännetecknas pojkarnas syn på framgångsfaktorer av kvalitetsmässigt god undervisning? I studiens resultat kan man dra slutsatsen att de båda perspektiven är beroende av varandra och att de grundläggande betingelserna är en faktor med stor vikt. En modell utifrån pojkarnas utsagor visar att skolkulturen eller skolans kontext blir en bärande faktor för övriga faktorer. Den lilla skolan och de små klasserna ger förutsättningar för lärarna att få tid till att möta eleverna och lära känna dem och deras behov var och en. Dessa möten är grunden till att en god relation kan skapas mellan elever och lärare och den goda relationen skapar trygghet och studiero. Detta sammanlagt ger förutsättningar för undervisning och lärande. Det som sedan händer i klassrummet är beroende av lärarens skicklighet och ambition att motivera, intressera och fånga eleverna. Det innebär också att skolans kultur är bärare av de värderingar som råder i pojkgruppen och förutsättningen för om en pluggkultur skapas istället för en antiplugg- eller antiansträngningskultur.
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Nogueira, Maria Lúcia Porto Silva. "A norma dos "bons costumes" e as resistências femininas nas obras de João Gumes (Alto Sertão Baiano, 1897-1930)." Pontifícia Universidade Católica de São Paulo, 2010. https://tede2.pucsp.br/handle/handle/12636.
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Previous issue date: 2010-12-01Conselho Nacional de Desenvolvimento Científico e Tecnológico
This research has as its object of analysis the gender representations in the Alto Sertão of Bahia, at the turn of the XIX century and the first decades of the XX century. It aims to evidence some cultural practices and social tensions that permeated the experiences of women and men in the society at that time. Based on João Gumes‟s literature, the intellectual backcountry man who described that region in his novelistic plots, it was possible to glimpse the details from the public-private in a dynamic full by the dominant moral values of that period and linked with a strong tradition. Gumes announced the backcountry reality, denounced social injustices and defended the residents from that region, but it wasn‟t his objective to release efforts in order to extinguish socio-cultural stereotypes from gender relationships or to criticize prejudices that existing about the feminine world. In the dialogue with these searches, the analysis focused on differentiated documents, emerging other visions from that same time. In a dialectic and dialogical posture this research aimed to focalized the experiences and women‟s daily actions, finding female identities in different rhythms permanencies, changes, resistances, transgressions despite the set of standards and beliefs that were imposed, at that time, in the context from the backcountry culture
Este trabalho tem como objeto de análise as representações de gênero no Alto Sertão da Bahia, na virada do século XIX e primeiras décadas do século XX, buscando evidenciar práticas culturais e tensões sociais que permeavam as vivências de homens e mulheres na sociedade da época. Partindo das obras literárias de João Gumes, o sertanejo intelectual que retratou a região em suas tramas romanescas, foi possível entrever os pormenores do público-privado numa dinâmica impregnada pelos valores morais dominantes no período e afinados com forte tradição conservadora. Gumes anunciou a realidade sertaneja, denunciou injustiças sociais e defendeu os moradores do sertão, mas não era seu objetivo desprender esforços para abolir estereótipos sócio-culturais das relações de gênero ou criticar preconceitos existentes sobre o mundo feminino. No contraponto com tais fontes, a análise debruçou-se sobre documentos diferenciados, fazendo emergir outras visões da mesma época. Numa postura dialética e dialógica, a pesquisa buscou focalizar as experiências e ações quotidianas das mulheres, encontrando identidades femininas em diferentes ritmos - permanências, mudanças, resistências, transgressões - a despeito de todo um conjunto de normas e crenças que lhes eram inculcadas, à época, no contexto da cultura sertaneja
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Boos, Adrian [Verfasser]. "The Relationship between the Resource Curse and Genuine Savings as an Indicator for Weak Sustainability : Theoretical Background and Empirical Evidence / Adrian Boos." Bonn : Universitäts- und Landesbibliothek Bonn, 2017. http://d-nb.info/1139118390/34.
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DeVolder, Ian John. "Language and reading dysfunction in boys with isolated cleft lip and/or palate : a relationship to abnormal structural and functional connectivity in the brain." Diss., University of Iowa, 2015. https://ir.uiowa.edu/etd/1964.
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Orofacial clefts are among the most common congenital defects in the United States, affecting roughly 1 in 600 births annually. A majority of these cases are considered to be “isolated” clefts of the lip and/or palate (ICLP). However the term “isolated” is somewhat of a misnomer, as functional deficits frequently accompany ICLP. One of the most problematic yet understudied of these deficits involves the high prevalence of reading disabilities in this population. It has been estimated that as high as 46% of children with ICLP will be diagnosed with a reading disability, particularly dyslexia. Despite this high prevalence and the well-established neurological basis of dyslexia, relatively little attention has been paid to the role that brain development plays in the reading problems in ICLP. Previous studies from our lab have demonstrated significant changes in brain structure in children with ICLP (that have importantly correlated with functional measures). However we have yet to combine both a structural and functional neuroimaging study with an in-depth analysis of reading dysfunction in this population.
The current study examined boys with ICLP, age 8-12 (boys have a higher prevalence of ICLP and show more significant reading problems that girls with ICLP) compared to healthy control boys. Measures of cognitive functioning were obtained with an emphasis on reading and language skills. In addition MRI scans were obtained which included volumetric measures, diffusion-weighted measures (DWI; white matter), and connectivity measures (resting-state fMRI). Even after controlling for the effect of socioeconomic status, boys with ICLP showed significant decreases in reading and language skills (particularly reading fluency). Boys with ICLP did not show significant differences on phonlogical measures (the primary cause of dyslexia). In addition, phonological measures were not predictive of reading fluency, while object naming tasks were predictive of reading fluency in boys with ICLP.
For white matter integrity, measures of fractional anisotropy (FA) were found to be increased in the right occipital lobe for boys with ICLP indicating more organized white matter in this region. This increase in right occipital FA was also predictive of better reading outcomes, particularly reading fluency. For more specific white matter tracts, only the fornix and the tapetum (both associated with the temporal lobes) showed a significant difference with a decrease in FA for boys with ICLP. The decrease in FA in the tapetum was also predictive of better reading outcomes in ICLP. When looking at resting-state networks, boys with ICLP showed an increase in connectivity within posterior and subcortical regions when compared to healthy control boys, indicating stronger network connections within the posterior language regions of the brain.
Taken together, these results point to differences in both structural and functional connectivity in the brains boys with ICLP. Furthermore, this pattern is different than that found in children with developmental dyslexia as there appears to be no disruption of the posterior reading systems. Cognitive measures also indicate normal phonological awareness in this group, further distinguishing them from dyslexic children. Boys with ICLP instead may be over-relying on these posterior, more visually oriented reading systems as a compensatory mechanism to overcome problems with the development of the typical “lexical route” of reading.
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Chen, Dan [Verfasser], Wilfried [Akademischer Betreuer] Bos, and Ramona [Gutachter] Lorenz. "The relationship between school leadership and student mathematics achievement : A comparative study between Germany and Chinese Taipei / Dan Chen ; Gutachter: Ramona Lorenz ; Betreuer: Wilfried Bos." Dortmund : Universitätsbibliothek Dortmund, 2019. http://d-nb.info/1185169482/34.
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Carpenter, Cherise Michelle. "Perceptions of gender socialization among African-American female caretakers." CSUSB ScholarWorks, 2001. https://scholarworks.lib.csusb.edu/etd-project/1968.
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Ochieng, Anne Achieng. "The relationship between environmental exposures to pesticides measured by means of environmental exposure indices and the anthropomentric outcomes of boys living on farms in the rural Western Cape." Master's thesis, University of Cape Town, 2011. http://hdl.handle.net/11427/12169.
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Includes abstract.Includes bibliographical references.
Few epidemiological studies have investigated the effect of pesticides on growth of boys and results are conflicting. Pesticide environmental exposure indices have not previously been developed. To investigate the effect of pesticide exposure using environmental exposure indices on pubertal growth of boys...
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Bowser, Jr Jimmy Lee. "The Relationship among Select School Variables and 8th Grade African American Male Academic Achievement." Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1248414/.
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This study was designed to investigate the correlational relationship between four school elements listed on the Texas Academic Progress Report (TAPR) and the academic achievement of 8th grade African American male students. Data for this study was provided from the Texas Education Agency's (TEA) Office for Public Information Requests. The study included four independent variables: percent of socioeconomically disadvantaged students, average years of teachers' experience, attendance rate and average class size in mathematics. The dependent variable was the 8th grade African American males' performance on the mathematics STAAR exam. The study examined scores from the mathematics STAAR exam for the years 2012-2014. The sample population included 1,540 schools and 47,169 individual test results. The results of the correlational analysis indicate that none of the independent variables were correlated to each other, but each of the independent variables had a statistically significant correlation with the dependent variable at the p < .05 level. The study also sought to explore the variance in academic achievement that could be explained by the four independent variables when used as a model. The results of the simple multiple regression suggest that not only were the results statistically significant at the p < .01 level, but the model explained 32.4% of the variance in 8th grade African American males' performance on the STAAR mathematics exam in the years 2012-2014.
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Coward-Reid, Mattie Francine. "A case study of the Concerned Black Men of Richmond mentor program for African American males: program structure and practices, perceptions of strengths and weaknesses, mentor-protege relationships." Diss., Virginia Tech, 1994. http://hdl.handle.net/10919/40162.
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Lefaix-Durand, Aurelia. "Customer-supplier relationships as a means of value creation : Les relations client-fournisseur comme outils de création de valeur." Thesis, Université Laval, 2008. http://www.theses.ulaval.ca/2008/25189/25189.pdf.
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La thèse soutenue dans cette étude établit les relations clients-fournisseurs comme des outils de création de valeur à privilégier pour améliorer la compétitivité des organisations. La recherche conduite pour valider cette thèse repose sur le cas particulier des fabricants canadiens de produits du bois et s’articule autour des étapes suivantes : exploration, théorisation et investigation empirique.
Tout d’abord, une étude exploratoire documente les principales tendances qui transforment le commerce des produits du bois structuraux en Amérique du Nord et fournit des données empiriques sur les stratégies d’approvisionnement des plus gros constructeurs aux États-unis. Les résultats soulignent la nécessité de placer la création de valeur et les relations interentreprises au cœur de la réflexion stratégique des fabricants canadiens de produits du bois pour leur permettre de réagir adéquatement aux changements détectés dans l’environnement d’affaires. En deuxième lieu, un modèle théorique est élaboré pour identifier les éléments clés du phénomène de création de valeur au sein des relations interentreprises et expliquer les liens entre ces éléments. Cette étape conduit à développer d’une part, le concept émergent de valeur des relations pour mesurer la création de valeur au sein des relations d’affaires et d’autre part, à développer un nouveau construit, l’orientation d’échange, afin de positionner la nature et la gouvernance des relations dans le continuum transactionnel/relationnel. Finalement, une étude de cas multiple est entreprise dans la chaîne d’approvisionnement nord-américaine des produits du bois structuraux pour examiner cette nouvelle approche valeur/orientation des relations interentreprises. Les résultats obtenus indiquent qu’une orientation d’échange relationnelle est associée à une valeur des relations supérieure pour les clients et à un avantage compétitif pour les fournisseurs. Les résultats n’incitent toutefois pas les gestionnaires à abandonner toute orientation transactionnelle mais à gérer stratégiquement leurs relations d’affaires en fonction de la valeur de ces relations et de l’orientation d’échange adéquate.
Ainsi, cette étude fonde le futur développement d’une théorie générale des relations d’affaires qui est nécessaire pour implanter une gestion stratégique des relations. La gestion stratégique des relations client-fournisseur est en effet perçue comme l’une des plus puissantes sources de création de valeur et d’avantage compétitif dans les décennies à venir.This dissertation argues that customer-supplier relationships are a means of value creation and represent a solution for organizations to increase their competitiveness. The research conducted to validate this thesis targets Canadian wood products manufacturers and follows the steps of exploration, theory building and empirical assessment. An exploratory study first documents the critical trends reshaping the supply chain of structural wood products for residential construction in North America and provides empirical data on procurement strategies of the largest U.S. homebuilders. Findings ground the necessity to focus on value creation and interfirm relationships to help Canadian wood products manufacturers capitalize on the changes detected in the business environment. A theoretical model is then built to identify and relate the key elements of the phenomenon of interfirm relationships as a means of value creation. This step leads to, on the one hand, extending the emergent construct of relationship value to measure value creation in relationships, and on the other hand, developing a new construct, exchange orientation, to position the nature and governance of relationships on the transactional/relational continuum. Finally, a multiple-case study investigates interfirm relationships in the North American supply chain for structural wood products through the lens of this new orientation/value approach to relationships. The findings indicate that a relational exchange orientation is associated with a superior relationship value for customers and with a competitive edge for suppliers. While the findings do not suggest abandoning a transactional orientation altogether, they do advocate that customer-supplier relationships should be strategically managed according to their value and the appropriate exchange orientation. This work thus underlies the future development of a general theory of business relationships. Such a theory will support the strategic management of customer-supplier relationships, likely to be one of the most powerful sources of value creation and competitive advantage in the next decades.
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Prelow, Hazel (Hazel M. ). "The Effects of Parental Substance Abuse on the Behavior of School Children." Thesis, University of North Texas, 1993. https://digital.library.unt.edu/ark:/67531/metadc501187/.
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The purpose of the present archival study was to investigate the relationship between parental substance abuse and the risk for maladjustment and psychopathology in children in a clinic sample. Children of alcoholic parents and children of drug-dependent parents were compared to children of non-substance abusing parents. The subjects were 83 boys age 6 to 12. Children of substance abuse parents had lower levels of adaptive functioning and higher levels of school behavioral problems. Although previous studies have reported a strong association between an adverse family environment and the risk of child maladjustment, the present study did not find that the addition of an adverse family environment increased the risk for maladjustment or school behavioral problems in children of substance abusers.
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Onsongo, Evans N. "Self-efficacy, Academic Engagement, and Student-teacher Relationships for Ninth-grade African American Male Students’ Algebra I Achievement: a Structural Equation Model." Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc822785/.
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The purpose of the current study was to discern the effects of three latent constructs – self-efficacy, academic engagement, and student-teacher relationships on Algebra I achievement among ninth-grade African American male students. A nationally representative sample from the High School Longitudinal Study of 2009 (HSLS09) was used in the study. Study participants were 697 African American males enrolled in ninth grade in the fall of 2009 across the United States. Structural Equation Modeling (SEM) analytical procedures were performed to test the hypothesized relationships of Bandura’s social cognitive theory (SCT) theoretical assumptions. The results indicate that the three latent variables directly or indirectly were related to Algebra I achievement among ninth grade African American male students. Moreover, the results revealed that self-efficacy and student-teacher relationships constructs had direct significant impact on Algebra I academic performance; nonetheless, the relationships were not strong. These two latent variables had small effect sizes of 5% and 1%, respectively. Combined, self-efficacy, academic engagement, and student-teacher relationships explained only 8% of the variance in the Algebra I achievement among African American males across the United States (R2=.08). The magnitude effect of these factors on Algebra I achievement was minimal. Overall, these findings suggest that the self-efficacy and student-teacher relationships latent variables had a negligible effect as predictors of Algebra I academic success among ninth grade African American male students. A summary of the results are presented and future research is recommended.
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Williams, Patricia Joanne. "Factors affecting Hispanic adolescent substance abuse." CSUSB ScholarWorks, 1996. https://scholarworks.lib.csusb.edu/etd-project/1137.
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Wolfe, Timothy W. "Fatherless homes and delinquency : a study of institutionalized African American male youth /." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-07212009-040512/.
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Vève, Jean-Christophe. "Interpretation microstructurale de l'endommagement par fatigue mecanique des fibres de polyester pour le renforcement des elastomeres." Paris, ENMP, 1987. http://www.theses.fr/1987ENMP0065.
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Analyse de l'evolution microstructurale des monofilaments de polyester 1) au cours de la fatigue par microspectrometrie laser a effet raman, diffusion rx aux petits angles et analyse viscoelastique dynamique et 2)avant sollicitation par diffusion rx aux grands angles et spectrometrie ir. Modele microstructural a 4 phases. Relation microstructures durabilite
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Dal, Maso Fabrice. "Influence du vieillissement thermique sur la morphologie et les proprietes du poly(fluorure de vinylidene) (pvf#2)." Paris 6, 1992. http://www.theses.fr/1992PA066104.
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L'objet de la these est de decrire et de correler les evolutions de la morphologie et des proprietes du poly(fluorure de vinylidene) (pvf#2) au cours du vieillissement thermique, en fonction des conditions de mise en forme, de la temperature et de la duree de recuit. Contrairement a la plupart des etudes sur le pvf#2, les echantillons utilises sont obtenus par compression sous forme de plaques epaisses de plusieurs millimetres. Le mode de refroidissement est le parametre de moulage qui influence le plus le comportement a long terme du materiau. Du point de vue mecanique, le materiau conserve de bonnes proprietes et se stabilise apres quelques jours de recuit. Un aspect etonnant de ce materiau est que sa ductilite augmente, bien que sa cristallinite augmente egalement. La micro-structure du materiau est un arrangement complexe d'unites cristallines et amorphes, qui peuvent etre considerees a plusieurs echelles. La description de la micro-structure a donc necessite l'emploi de plusieurs techniques de caracterisation physico-chimiques (calorimetrie, diffraction des rayons x, microscopie, etc. ). La structure cristalline preferentiellement adoptee est la phase alpha. Le vieillissement n'entraine pas de transitions allotropiques. Par contre, l'organisation des zones cristallines est complexe et on observe des evolutions au niveau de la conformation des chaines, des empilements des chaines dans le cristal et de l'organisation des micro-domaines cristallins. C'est grace a la simulation des spectres des rayons x aux grands angles qu'il a ete possible de comprendre les evolutions des zones cristallines au cours du recuit. Une seconde approche, originale, a consiste a coupler un module de simulation de spherolites avec une simulation de diffraction des rayons x aux petits angles. Ces deux methodes de simulation informatique nous ont permis d'ameliorer la description de la structure du pvf#2 et d'autres polymeres semi-cristallins
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PANINE, PIERRE. "Membranes polymères asymétriques : instabilité diffusionnelle et initiation des macrovides." Université Joseph Fourier (Grenoble), 1998. http://www.theses.fr/1998GRE10010.
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La motivation de cette etude est d'expliquer l'apparition des macrovides aux tous premiers instants de la formation de la membrane. Il s'agit des lors de relier quantitativement les differents parametres d'elaboration des membranes a l'apparition des doigts de gant et a leur repartition sous la surface. La regularite de l'espacement des macropores sous la surface suggere, au moment de leur initiation, la presence d'un phenomene d'instabilite. Une analogie avec l'instabilite gravitationnelle de rayleigh-taylor a permis recemment l'avenement d'un modele quantitatif (cohen-addad, 1996). L'objet de cette recherche est de valider experimentalement ce modele. De nombreuses techniques ont ete mises en oeuvre pour caracteriser le milieu polymere, avant et apres la formation de la membrane. La rmn a ete utilisee pour determiner l'etat thermodynamique de la solution polymere par un acces quantitatif a la dynamique des milieux, mais aussi pour etudier l'evolution du coefficient de diffusion des molecules de solvant dans la solution polymere et dans le bain de coagulation. En outre, la calorimetrie a permis de quantifier la chaleur de formation de melanges polymere / solvant ou encore de melanges solvant / non-solvant et d'evaluer le gradient de potentiel chimique < du solvant existant entre la solution polymere et le bain de coagulation. La video-microscopie a donne acces aux parametres statistiques de la structure de la membrane, comme la distance moyenne entre macropores. La dsc, la rheologie et la tensiometrie ont egalement ete employees, fournissant des donnees essentielles a la comprehension des systemes etudies. Le modele predictif propose par cohen-addad (cohen-addad, 1997) est utilise pour representer l'evolution de l'espacement moyen des macrovides en fonction de la composition de la solution et du bain de coagulation utilises pour l'elaboration de la membrane. Ce modele, elabore a partir d'une analogie avec le modele d'instabilite gravitationnelle de rayleigh-taylor, est base sur une analyse du comportement diffusionnel du solvant vers le non-solvant. On obtient une superposition des points experimentaux avec une variation lineaire de #* en fonction de ds#-#1, dependant du systeme polymere / solvant / non-solvant etudie. Ce comportement lineaire a ete verifie sur six systemes appartenant a deux familles de polymeres, le polyacrylonitrile et le polyetherimide. Le modele d'instabilite diffusionnelle, dont la force motrice est <, autorise l'utilisation de parametres d'acces simples : l'evaluation du gradient de potentiel chimique < du solvant entre la solution et le bain par des mesures de calorimetrie a dilution a montre que l'approche purement entropique du modele est une approximation raisonnable.