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La interlengua de los estudiantes francófonos de ELE : el caso de ser y estarAgudelo, Sandra Paola 05 1900 (has links)
No description available.
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The effect of eicosapentaenoic acid on brain and platelet produced bioactive lipid mediators. The effect of eicosapentaenoic acid, docosapentaenoic acid and other polyunsaturated fatty acids on the eicosanoids and endocannabinoids produced by rat brain and human platelets using electrospray ionisation tandem mass spectrometry-based analysis.Mir, Adnan A. January 2009 (has links)
Eicosapentaenoic acid (EPA) is a polyunsaturated fatty acid (PUFA) with neuroprotective and cardioprotective properties. It is thought that some of the actions of EPA may be attributed to its elongated metabolite, the PUFA docosapentaenoic acid (DPA). Docosahexaenoic acid (DHA) and arachidonic acid (AA) are bioactive PUFA ubiquitously expressed in neural tissues. EPA and AA can be converted by cyclooxygenase (COX) to prostanoids and by lipoxygenase (LOX) to hydroxy fatty acids. PUFA can also be converted to ethanolamides in the brain. These mediators are involved in physiological and pathological processes in many bodily systems.
The purpose of this study was to examine the production of eicosanoids, hydroxy fatty acids and fatty acid ethanolamides in young and aged rat brain following EPA or DPA enriched diets. The effects of specific PUFA on human platelet eicosanoid production were also investigated as these mediators play a role in adhesion and aggregation. Liquid chromatography coupled to tandem mass spectrometry (LC/ESI-MS/MS) assays were developed and used to measure lipid mediators in rat brain and human platelets.
Ageing in rat brain was accompanied with several changes in the prostanoid and hydroxy fatty acid profiles. Supplementing the diet with EPA or DPA at a daily dose of 200 mg/kg for 8 weeks prevented these changes and decreased levels of PGE2. DPA changed the profile of hydroxy fatty acids synthesised in the brain tissue of young animals. This study has shown that levels of eicosapentaenoylethanolamide (EPA-EA) increase in the brain as a result of ageing and that this is accompanied by an increase in levels of anandamide. Feeding aged animals EPA or DPA further increased the levels of EPA-EA but prevented any change in the level of anandamide.
Niacin is used to treat hypercholesterolaemia although it is associated with an unpleasant PGD2 mediated skin flush. This exploratory study has shown that human platelets treated with niacin did not show any changes in their prostanoid and hydroxy fatty acid profiles. Platelets treated with EPA showed increased production of TXB3 and 12-HEPE. Niacin augmented the effects of EPA on human platelet mediator synthesis.
Overall, this study has demonstrated that EPA can change brain and platelet lipid mediator synthesis and has provided evidence that could explain some of the neuroprotective and cardioprotective actions of this PUFA.
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Prepositional Errors in Swedish Upper Secondary School Students’ English Written ProductionBillingfors, Caroline January 2024 (has links)
The aim of the study is to find out to what extent Swedish learners of English, in the first year of upper secondary school, make prepositional errors in their written production, and to what extent these errors can be attributed to negative transfer, overgeneralization and simplification by conducting an Error Analysis. A comparison between gender and type of program, academic and vocational, is made to find out in which type of program most errors appear and if there is any difference in terms of gender. The data is annotated from the Swedish Learner English Corpus (SLEC), which consists of argumentative essays written by Swedish learners of English, and it consists of 24 randomly selected texts based on the variables binary gender, type of program, Swedish as their L1, school year, and English course. All the texts selected are written by students in the first year of upper secondary school studying the course English 5. The results of the study reveal that Swedish learners of English struggle with prepositional usage. In total, 649 prepositions were identified in the 24 texts. Out of these, 72 (11.09%) were used incorrectly. The most frequently used prepositions involved in these errors are of, for, in, to, and with. Most errors appear when prepositional phrases function as post-modifiers in noun phrases. Substitution is, by far, the most common type of error found, meaning that the students replace the correct preposition with an incorrect one. The results thus show that the students seem to be aware that a preposition should be used although they fail to choose the correct one. Female students make more prepositional errors than male students; similarly, students attending vocational programs make more prepositional errors than students attending academic programs. Most errors are cases of overgeneralizations, followed by negative transfer from Swedish, and simplification. However, many of the errors can still be attributed to negative transfer which suggests that, even though Swedish and English are similar languages which could lead to positive transfer, this does not seem to fully apply to prepositions.
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'n Vergelykende studie tussen Pt en Pd vir die elektro-oksidasie van waterige SO₂ asook ander model elektrochemiese reaksies / Adri YoungYoung, Adri January 2014 (has links)
The pressure on clean and sustainable energy supplies is increasing. In this regard energy conversion by electrochemical processes plays a major role, for both fuel cell reactions and electrolysis reactions. The sulphur dioxide oxidation reaction (SOR) is a common reaction found in the Hybrid Sulphur Cycle (HyS) and the HyS is a way to produce large-scale hydrogen (H2). The problem with the use of the HyS and fuel cells is the cost involved as large amounts of Pt are required for effective operation. The aim of the study was to determine whether there was an alternative catalyst which was more efficient and cost-effective than Pt. The oxygen reduction reaction (ORR), the ethanol oxidation reaction (EOR) and SOR were studied by means of different electrochemical techniques (cyclovoltammetry (CV), linear polarization (LP) and rotating disk electrode (RDE)) on polycrystalline platinum (Pt) and palladium (Pd). The SRR and EOR are common reactions occurring at the cathode and anode, respectively, in fuel cells and these reactions have been investigated extensively. The reason for studying the reactions was as a preparation for the SOR.
This study compared polycrystalline Pt and Pd for the different reactions, with the main focus on the SOR as Pd is considerably cheaper than Pt, and for the SOR polycrystalline Pd has by no means been investigated intensively. Polycrystalline Pt and Pd were compared by different electrochemical techniques and analyses. The Koutecky-Levich and Levich analyses were used to (i) calculate the number of e- involved in the relevant reaction, (ii) to determine whether the reaction was mass transfer controlled at high overpotentials and (iii) whether the reaction mechanism changed with potential. Next the kinetic current density ( k) was calculated from Koutecky-Levich analyses, which was further used for Tafel slope analyses. If it was not possible to carry out the analyses, the activation energy (Ea) was used to determine the electrocatalytic activity of the catalyst. The electrocatalytic activity was also determined by comparing onset potentials (Es), peak potentials (Ep) and limited/maximum current density ( b/ p) of each catalyst. This study was only a preliminary study for the SOR and therefore, further studies are certainly required. It seemed Pd shows better electrocatalytic activity than Pt for the SRR in an alkaline electrolyte because of similar Es, but Pd produced a higher cathodic current density. Pt showed a lower Es than Pd for the SRR in an acid electrolyte, but Pd delivered a higher cathodic current density. This, therefore, means that the SRR in an acid electrolyte is kinetically more favourable on Pd than on Pt. For the EOR better electrocatalytic activity was obtained with Pd than with Pt in an alkaline electrolyte due to higher current densities at lower potentials and Pd showed lower Ea values than Pt in the potential range normally used for fuel cells. Pd was inactive for EOR in an acid electrolyte, while a reaction occurred on Pt. A possible reason for this observation may be due to the H2 absorbing strongly on Pd thus blocking the active positions on the electrode surfaces, preventing further reaction. Pd showed higher electrocatalytic activity for the SOR due to lower Es and higher current densities at low potentials.
From the RDE studies it was established that the SRR in an alkaline electrolyte on polycrystalline Pt and Pd was mass transfer controlled at low potentials (high overpotentials), but the SRR in an acid electrolyte was only mass transfer controlled on Pt. The SOR was not mass transfer controlled on polycrystalline Pt and Pd at high potentials (high overpotentials). These assumptions were confirmed by Levich analysis.
Using Koutecky-Levich analysis, it was determined that the reaction mechanism on polycrystalline Pt and Pd changed with potential for SRR in an alkaline electrolyte and the SOR. For the SRR in an acid electrolyte the reaction mechanism remained constant with changes in potential on polycrystalline Pd, but the reaction mechanism on polycrystalline Pt changed with potential. These assumptions were confirmed by the number of e-, calculated using Koutecky-Levich analyses. Levich and Koutecky-Levich analyses were not performed for EOR as an increase in rotation speed did not produce an increase in current density.
Tafel slope analyses were conducted by making use of overpotentials and k, where possible. As in the case of ethanol, it was not possible to execute Koutecky-Levich analyses and, therefore, it was not possible to perform Tafel slope analyses using k. Tafel slope analyses for the EOR was therefore performed with normal current densities at 0 rotations per minute (rpm). The reaction mechanisms on Pt and Pd for the SRR in alkaline and acidic electrolytes differed due to different Tafel slopes. Pt and Pd displayed similar Tafel slopes for the EOR in alkaline electrolyte, thus suggesting that the reaction mechanisms on Pt and Pd were the same. For the SOR it seemed that the reaction mechanism on Pt and Pd were similar because of similar Tafel slopes. This was only a preliminary and comparative study for polycrystalline Pt and Pd, and the reaction mechanism was not further studied by means of spectroscopic techniques. / MSc (Chemistry), North-West University, Potchefstroom Campus, 2014
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'n Vergelykende studie tussen Pt en Pd vir die elektro-oksidasie van waterige SO₂ asook ander model elektrochemiese reaksies / Adri YoungYoung, Adri January 2014 (has links)
The pressure on clean and sustainable energy supplies is increasing. In this regard energy conversion by electrochemical processes plays a major role, for both fuel cell reactions and electrolysis reactions. The sulphur dioxide oxidation reaction (SOR) is a common reaction found in the Hybrid Sulphur Cycle (HyS) and the HyS is a way to produce large-scale hydrogen (H2). The problem with the use of the HyS and fuel cells is the cost involved as large amounts of Pt are required for effective operation. The aim of the study was to determine whether there was an alternative catalyst which was more efficient and cost-effective than Pt. The oxygen reduction reaction (ORR), the ethanol oxidation reaction (EOR) and SOR were studied by means of different electrochemical techniques (cyclovoltammetry (CV), linear polarization (LP) and rotating disk electrode (RDE)) on polycrystalline platinum (Pt) and palladium (Pd). The SRR and EOR are common reactions occurring at the cathode and anode, respectively, in fuel cells and these reactions have been investigated extensively. The reason for studying the reactions was as a preparation for the SOR.
This study compared polycrystalline Pt and Pd for the different reactions, with the main focus on the SOR as Pd is considerably cheaper than Pt, and for the SOR polycrystalline Pd has by no means been investigated intensively. Polycrystalline Pt and Pd were compared by different electrochemical techniques and analyses. The Koutecky-Levich and Levich analyses were used to (i) calculate the number of e- involved in the relevant reaction, (ii) to determine whether the reaction was mass transfer controlled at high overpotentials and (iii) whether the reaction mechanism changed with potential. Next the kinetic current density ( k) was calculated from Koutecky-Levich analyses, which was further used for Tafel slope analyses. If it was not possible to carry out the analyses, the activation energy (Ea) was used to determine the electrocatalytic activity of the catalyst. The electrocatalytic activity was also determined by comparing onset potentials (Es), peak potentials (Ep) and limited/maximum current density ( b/ p) of each catalyst. This study was only a preliminary study for the SOR and therefore, further studies are certainly required. It seemed Pd shows better electrocatalytic activity than Pt for the SRR in an alkaline electrolyte because of similar Es, but Pd produced a higher cathodic current density. Pt showed a lower Es than Pd for the SRR in an acid electrolyte, but Pd delivered a higher cathodic current density. This, therefore, means that the SRR in an acid electrolyte is kinetically more favourable on Pd than on Pt. For the EOR better electrocatalytic activity was obtained with Pd than with Pt in an alkaline electrolyte due to higher current densities at lower potentials and Pd showed lower Ea values than Pt in the potential range normally used for fuel cells. Pd was inactive for EOR in an acid electrolyte, while a reaction occurred on Pt. A possible reason for this observation may be due to the H2 absorbing strongly on Pd thus blocking the active positions on the electrode surfaces, preventing further reaction. Pd showed higher electrocatalytic activity for the SOR due to lower Es and higher current densities at low potentials.
From the RDE studies it was established that the SRR in an alkaline electrolyte on polycrystalline Pt and Pd was mass transfer controlled at low potentials (high overpotentials), but the SRR in an acid electrolyte was only mass transfer controlled on Pt. The SOR was not mass transfer controlled on polycrystalline Pt and Pd at high potentials (high overpotentials). These assumptions were confirmed by Levich analysis.
Using Koutecky-Levich analysis, it was determined that the reaction mechanism on polycrystalline Pt and Pd changed with potential for SRR in an alkaline electrolyte and the SOR. For the SRR in an acid electrolyte the reaction mechanism remained constant with changes in potential on polycrystalline Pd, but the reaction mechanism on polycrystalline Pt changed with potential. These assumptions were confirmed by the number of e-, calculated using Koutecky-Levich analyses. Levich and Koutecky-Levich analyses were not performed for EOR as an increase in rotation speed did not produce an increase in current density.
Tafel slope analyses were conducted by making use of overpotentials and k, where possible. As in the case of ethanol, it was not possible to execute Koutecky-Levich analyses and, therefore, it was not possible to perform Tafel slope analyses using k. Tafel slope analyses for the EOR was therefore performed with normal current densities at 0 rotations per minute (rpm). The reaction mechanisms on Pt and Pd for the SRR in alkaline and acidic electrolytes differed due to different Tafel slopes. Pt and Pd displayed similar Tafel slopes for the EOR in alkaline electrolyte, thus suggesting that the reaction mechanisms on Pt and Pd were the same. For the SOR it seemed that the reaction mechanism on Pt and Pd were similar because of similar Tafel slopes. This was only a preliminary and comparative study for polycrystalline Pt and Pd, and the reaction mechanism was not further studied by means of spectroscopic techniques. / MSc (Chemistry), North-West University, Potchefstroom Campus, 2014
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An exploration of the design of job descriptions in the South African Police Service / Incazo banzi yenkcazelo yomsebenzi wamaPolisa WomMzantsi Africa / Ho hlahlisoa ha tšebeletso ea litlhahiso tsa jobe tšebeletsong ea Mapolesa a South AfricaSmit, Lindie 01 1900 (has links)
The research entailed an exploration of the design of job descriptions (JDs) in the South African Police Service (SAPS). A JD represents an official document that defines general duties, tasks, and related job responsibilities. It details the job features and the essential abilities required to perform the job. JDs are fundamental and vital to outline the job duties harmonised with the relevant organisation’s policy, ethos, goals, mission, and vision. Participants in this study were purposefully chosen to conduct semi-structured interviews and focus groups with information-rich SAPS Human Resource (HR) practitioners from both the support and operational career streams, to gain their insights into and viewpoints on the JD processes in the SAPS. The National Head Office: Divisions: Human Resource Utilisation (HRU) and Operational Response Service (ORS) and the information-rich provincial HR practitioners who support and monitor the implementation of JDs in the SAPS were included in this study. The participants were asked to answer open-ended questions that aimed to explore the design of JDs in the SAPS. The interviews were recorded with the participants’ permission.
The recorded information was translated verbatim and analysed. The six fundamental themes that emerged are: value and benefits of JDs; processes to coordinate and monitor JDs to ensure effective management; the potential of JDs to enhance police performance; knowledge and skills for designing JDs; attitudes, experiences, and challenges of JDs; and recommendations of electronic JD systems. The topics were delineated using direct quotations from the participants as gained during the interviews. Opinions, experiences, administrative aspects, and criticism of the various features of JDs in the SAPS was explored. In summary, the research recommendations and conclusion were given. The results of this study show there are several factors that can enable and optimise inclusion in the effective designing process of JDs in the SAPS. / Ucwaningo lubandakanya ukuhlolisiswa komdwebo wezincazelo zemisebenzi (JDs) eNingizimu Afrika Amaphoyisa (SAPS). I-JD imelela idokhumenti esemthethweni echaza imisebenzi ejwayelekile, imisebenzi, kanye nemithwalo yemisebenzi ehlobene. It ichaza izici zomsebenzi kanye namakhono abalulekile adingekayo ukuze enze lo msebenzi. I-JDs iyigugu futhi ibalulekile ukuchaza imisebenzi ehambisana nomgomo wenhlangano efanele, izinhloso, izinhloso, umsebenzi kanye nombono. Abahlanganyeli kulolu cwaningo babekhethwe ngenhloso yokuqhuba izingxoxo ezihleliwe kanye namaqembu okugxila abasebenza nge-SAPS Human Resource (HR) abaqeqeshiwe abavela kuzo zombili ukusekela nokusebenza kwemifudlana yomsebenzi, ukuze bathole ukuqonda kwabo kanye nokubukwa kwizinhlelo ze-JD kuma-SAPS. I-Ofisi Eyinhloko Kazwelonke: Izigaba: Ukusetshenziswa Kwemithombo Yabantu (HRU) kanye ne-Operational Response Service (ORS) kanye nabasebenzi abacebile be-HR esifundazweni abanolwazi abaxhasa futhi baqaphe ukuqaliswa kwe-JDs kuma-SAPS bafakiwe kulolu cwaningo. Abahlanganyeli babuzwa ukuthi baphendule imibuzo evulekile ehlose ukuhlola ukuklama kwama-JD ku-SAPS. Lezi zincwadi zabhalwa nemvume yabahlanganyeli.
Ulwazi olurekhodiwe luhunyushwe ngokucacile futhi luhlaziywe. Izingqikithi eziyisithupha eziyisisekelo ezivela ziyizi: inani nenzuzo ye-JDs; izinqubo zokuxhumanisa nokuqapha i-JDs ukuqinisekisa ukuphathwa okuphumelelayo; ikhono lama-JDs ukuthuthukisa ukusebenza kwamaphoyisa; ulwazi namakhono wokwakha i-JDs; isimo sengqondo, okuhlangenwe nakho, nezinselelo ze-JDs; kanye nezincomo zezinhlelo ze-JD zobuchwepheshe. Izihloko zachazwa ngokucaphuno okuqondile kusuka kubahlanganyeli njengoba zitholakale ngesikhathi sokuxoxisana. Imibono, okuhlangenwe nakho, izici zokuphatha, nokugxeka izici ezihlukahlukene ze-JDs ku-SAPS kuhlolwe. Ngamafuphi, izincomo zocwaningo nesiphetho zanikezwa. Imiphumela yalolu cwaningo ibonisa ukuthi kunezici eziningana ezingasiza futhi zenzeke ukufakwa ekusebenzeni okuphumelelayo kwe-JDs kuma-SAPS. / Phuputso e kenyeletsa ho hlahloba moralo oa litlhaloso tsa mosebetsi (JDs) Lefapheng la Mapolesa a Afrika Boroa (SAPS). JD e emela tokomane ea molao e hlalosang mesebetsi e tloaelehileng, mesebetsi le mesebetsi e amanang le mosebetsi. E hlalosa lintlha tsa mosebetsi le bokhoni ba bohlokoa bo hlokahalang bakeng sa ho etsa mosebetsi. Li-JDs ke tsa motheo le tsa bohlokoa ho hlalosang mesebetsi e lumellanang le leano la mokhatlo o hlophisitsoeng, litokelo, lipakane, mosebetsi le pono. Barupeluoa thutong ena ba ne ba khethiloe ka boomo ho etsa lipuisano tse hlophisitsoeng hantle le lihlopha tse tsepamisisang maikutlo le basebeletsi ba ruileng ba SAPS Human Resource (HR) ba tšehetso le litšebeletso tsa mesebetsi e le hore ba fumane litlhaloso tsa bona le maikutlo a bona ka ts'ebetso ea JD SAPS. Lekala la Sechaba: Likarohano: Tšebeliso ea Lisebelisoa tsa Botho (HRU) le Tšebeletso ea Likarabo tsa Ts'ebetso (ORS) le basebetsi ba ruileng ba profinseng ba HR ba tšehetsang le ho shebella ts'ebetsong ea JDs ho SAPS ba kenyelelitsoe thuputsong ena. Barupeluoa ba ile ba botsoa hore ba arabe lipotso tse bulehileng tse neng li reretsoe ho hlahloba moralo oa JDs ho SAPS. Lipuisano li ngotsoe ka tumello ea barupeluoa.
Boitsebiso bo tlalehiloeng bo fetoletsoe ka mantsoe le ho hlahlojoa. Lihlooho tse tšeletseng tsa bohlokoa tse hlahang ke: boleng le melemo ea JDs; e sebetsana le ho hokahanya le ho hlahloba li-JD ho etsa bonnete ba hore tsamaiso e nepahetseng; bokhoni ba JDs ho ntlafatsa ts'ebetso ea mapolesa; tsebo le bokhoni ba ho theha JDs; boikutlo, liphihlelo le mathata a JDs; le litlhahiso tsa mekhoa ea JD ea elektronike. Lihlooho li hlalositsoe ka litlhaloso tse tobileng ho tsoa ho barupeluoa tse fumanoang nakong ea lipuisano. Maikutlo, liphihlelo, likarolo tsa tsamaiso, le ho nyatsa likarolo tse sa tšoaneng tsa JDs li SAPS li ile tsa hlahlojoa. Ka kakaretso, liphuputso le liphello li ile tsa fanoa. Liphello tsa phuputso ena li bonts'a hore ho na le lintlha tse 'maloa tse ka khonang le ho ntlafatsa ho kenngoa tshebetsong e sebetsang ea ho qapa li-JDs ho SAPS. / Police Practice / D. Litt. et Phil. (Police Science)
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Etude de la production et de l'émanation de composés volatils malodorants sur textile à usage sportif / Production and emission of human body odors from textile for sportsLéal, Françoise 04 November 2011 (has links)
Si la sueur fraîchement émise par le corps humain est inodore, la dégradation de celle-ci par la flore bactérienne cutanée produit des composés volatils malodorants, responsables des odeurs de transpiration. Les odeurs de transpiration apparaissent également sur les vêtements au cours de leur utilisation, particulièrement sur les textiles réalisés en fibres synthétiques. Ce travail a pour but d’améliorer la compréhension du phénomène d’émanation d’odeurs en étudiant l’effet du sujet testé, l’effet de la flore bactérienne et l’effet du textile sur les émissions de composés volatils malodorants.L’intérêt de ce travail réside dans l’approche globale de la problématique des odeurs de transpiration et dans la diversité des méthodes de mesure mises en place, tant dans l’étude de la flore microbiologique que dans les méthodes de mesures des composés odorants émis.Dans un premier temps, le dénombrement simultané de la flore bactérienne sur la peau et sur le vêtement a été réalisé sur un échantillon de 15 sujets à l’issue d’un exercice physique. Cette expérimentation a permis d’évaluer le taux de transfert bactérien moyen lors d’une activité sportive et d’étudier son rôle dans l’émission d’odeurs. Ensuite, afin d’affiner ces résultats, une méthode basée sur la biologie moléculaire a été mise en place pour réaliser le suivi qualitatif de la stabilité de la flore commensale axillaire d’un sujet pendant 3 mois. Le transfert bactérien spécifique entre la peau du testeur et le vêtement a été étudié pour 4 matières textiles sélectionnées (dont le coton et le PET). Ceci a permis de déterminer le rôle du transfert bactérien spécifique dans l’émission des odeurs à partir de textile.Enfin, le dernier chapitre est consacré à l’étude de l’émission de composés volatils et odorants à l’aide de mesures olfactives et d’un nez électronique au cours du temps par 8 composants textiles sélectionnés. Après traitement statistique par analyse en composante principale et étude détaillée des mesures, 9 composés chimiques ont été identifiés comme indicateurs d’un comportement textile malodorant. Ces derniers pourraient être utilisés dans la mise en place d’une méthode ciblée de mesure physico-chimique des mauvaises odeurs.Ce travail a permis de déterminer l’impact de chacun des facteurs sujet, flore bactérienne et textile dans l’émission d’odeurs. En outre, ce travail ouvre des perspectives sur l’étude des contaminations bactériennes par contact, mais également dans l’étude des odeurs, sur les phénomènes de désorption de molécules volatiles à partir de différentes matrices textiles et sur les solutions pouvant être envisagées pour limiter les émissions odorantes à partir de textiles. / Fresh human sweat is odorless. Odoriferous volatile compounds are produced by the metabolism of bacteria living on the skin, generating strong malodor. Sweaty body odors do also appear on clothes during use, and especially on synthetic fabrics. The aim of this document is to improve understanding of odor emission by investigating subject effect, microbiota effect and fabric effect on the emission of odoriferous volatile compounds.Odors of perspiration are hereby globally approached with a wide use of methods and experimental devices, for microbial flora study as well as for odoriferous volatile compounds emission study.First, microflora enumeration has been simultaneously processed on the skin and on the fabric after exercise for 15 subjects. This experiment allowed an evaluation of the average bacterial transfer yield during physical activity and the beginning of the investigation of its effect on odor emission.A molecular biology methodology has then been developed in order to refine these results. Monitoring of qualitative composition of the microbiota has been performed to study the stability of the armpit’s ecosystem on a subject during 3 months. Specific microbial transfer from subject’s skin to clothe has been performed for 4 textile fabrics (including cotton and PET). This leaded to characterize the effect of specific bacterial transfer on odor emission from fabric.The last chapter is dedicated to the study of the emission of odoriferous volatile compounds over time using olfactory measurements and electronic nose for 8 selected fabrics. Principal component analysis targeted 9 chemical compounds that have been selected as malodorous behavior indicators for a given fabric. Those 9 compounds could be used for setting up a fitted physicochemical method of malodor.To conclude, this study helped to understand the effect of 3 factors in odor perception from a fabric after sport : subject, microbial flora and fabric. Perspectives have been charted on contact microbial contamination, but also on odor, and especially on desorption of odoriferous volatile molecules from a textile or knitted matrix. The solutions that could be used to limit malodorous emission from fabrics have also been discussed.
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Greening the school for sustainable development: a case of Tshwane North DistrictBopape, Johannah 01 1900 (has links)
This study is environmental in nature, occurring within a series of nested frameworks, namely school role players, sustainable development and greening schools. From a South African context, the day-to-day operations of the school activities and programmes are not solely the principal’s responsibility. It is a shared responsibility among every person involved in an educational school context. The principal has the overall responsibility of leading and professionally managing the school through the school management team (SMT) and is accountable to the employer, which is the provincial Head of the Department of Education. The principal is also accountable to the community through the school governing body (SGB), which consists of elected representatives from the school community. This study was guided by these research questions: (1) What is the nature of the knowledge of the role players in the Tshwane North District schools about greening the school? (2) How do the contextual factors in the Tshwane North District schools shape the greening of the school? The SMT and SGB are key role players and gatekeepers at the school level. They were purposefully and conveniently sampled at three Tshwane North District (TND) primary schools in Gauteng Province of South Africa according to their locations (rural, township, urban). They participated in focus group interviews, observations and document analysis. The study, qualitative in nature, explored strengths, weaknesses, opportunities and threats in greening the school for sustainable development. The two role players might not be knowledgeable about green and sustainable development, however given the opportunity to explore their knowledge, provided insight about greening schools and how to possibly change to more sustainable practices. Data collected was subjected to thematic content analysis. The results revealed that schools’ funds are swiftly depleted on resources such as water, energy, transportation, paper, stationary, maintenance and equipment, to name but a few. The results also revealed limited green culture across institutions, due to little knowledge of greening and sustainability practices by school role players. This was attributed to a lack of policy framework by schools which was exacerbated by a lack of capacity building from expertise in greening schools for sustainable development. / Hierdie studie is omgewings van aard wat plaasvind binne 'n reeks nes raamwerke, naamlik skoolrolspelers, volhoubare ontwikkeling en vergroening van skole. Uit 'n Suid-Afrikaanse konteks is die dag-tot-dag-bedrywighede van die skoolaktiwiteite en -programme nie net die skoolhoof se verantwoordelikheid nie. Dit is 'n gedeelde verantwoordelikheid onder elke persoon wat in 'n opvoedkundige skoolverband betrokke is.Die skoolhoof het die oorhoofse verantwoordelikheid om die skool deur die skoolbestuurspan (SUT) te lei en professioneel te bestuur en is verantwoordbaar teenoor die werkgewer, wat die provinsiale hoof van die departement van onderwys is.Die skoolhoof is ook deur die skoolbeheerliggaam (SGB) aan die gemeenskap verantwoordbaar, wat uit verkose verteenwoordigers uit die skoolgemeenskap bestaan.Die SMT en SGB is sleutelrolspelers en hekwagters op skoolvlak.Hulle is volgens hul plekke (landelike, township, stedelike) doelgerigte en gerieflik by drie Tshwane-Noord-distrikskole (TND) in Gautengprovinsie van Suid-Afrika gemonster.Hulle het deelgeneem aan fokusgroeponderhoude, waarnemings en dokumentanalise.Die studie, kwalitatiewe van aard wat daarop gemik is om sterk punte, swakhede, geleenthede en bedreigings te ondersoek om die skool vir volhoubare ontwikkeling te verging Die twee rolspelers is dalk nie kundig oor groen en volhoubare ontwikkeling nie, maar gegewe die geleentheid om hul kennis te ondersoek, het hulle 'n insig gegee oor groen skole en moontlik verandering aan volhoubare gedrag.Data wat ingesamel is, is aan tematiese inhoudsanalise onderwerp. Die bevindinge het aan die lig gebring dat skole se fondse vinnig uitgeput is op hulpbronne soos water, energie, vervoer, papier, stilstaande, instandhouding en toerusting om maar net 'n paar te noem.Die bevindinge het ook min kennis van vergroenings- en volhoubaarheidspraktyke deur skoolrolspelers geopenbaar.Dit is toegeskryf deur 'n gebrek aan beleidsraamwerke deur skole wat vererger is deur 'n gebrek aan kapasiteitsbou van kundigheid in die vergroening van skole vir volhoubare ontwikkeling. / Thutong ena ke ea tikoloho e hlahang ka hara letoto la meralo, e leng, ba nkang karolo ea sekolo, ntshwetsopele ea nako e telele le likolo tse tala.Ho tsoa maemong a Afrika Boroa, tshebetso ea letsatsi le letsatsi ea mesebetsi ea sekolo le mananeo ha se feela boikarabello ba mosuoe-hlooho.Ke boikarabello bo arolelanoeng hara motho e mong le e mong ea amehang molemong oa sekolo sa thuto.Hlooho ea sekolo e na le boikarabello ka kakaretso ba ho etella pele le ho tsamaisa sekolo ka sehlopha sa botsamaisi ba sekolo (SMT) mme o ikarabella ho mohiri, e leng Hlooho ea profinse ea Lefapha la Thuto.Hlooho ea sekolo e boetse e ikarabella ho sechaba ka sehlopha se busang sa sekolo (SGB), se nang le baemeli ba khethiloeng ba tsoang sechabeng sa sekolo.SMT le SGB ke karolo ea bohlokoa le balebeli ba liheke boemong ba sekolo.Li ile tsa etsoa sampole ka morero le ka mokhoa o bonolo likolong tse tharo tsa mathomo tsa Tshwane North (TND) tse Profinseng ea Gauteng ea Afrika Boroa ho latela libaka tsa bona (mahaeng, metse-literopong, le toropong).Maloko a SMT le SGB ba nkile karolo lipuisanong tsa sehlopha se tsepamisitseng maikutlo, maikutlo le tlhahlobo ea litokomane.Boithuto bona, bo nang le boleng ba tlhaho bo ikemiselitse ho lekola matla, bofokoli, menyetla le litšokelo ho silafatsa sekolo bakeng sa ntshetsopele e tsitsitseng. Baetsi ba karolo ba babeli ba kanna ba se be le tsebo mabapi le ntshetsopele ea botala le bo tsitsitseng, empa ba fuoe monyetla oa ho lekola tsebo ea bona, ba fane ka leseli mabapi le likolo tse talafatsang mme mohlomong li fetohela mekhoeng e tsitsitseng.Boitsebiso bo bokelletsoeng bo ile ba hlahlojoa ka litaba tsa bona, mme liphuputso li senotse hore lichelete tsa likolo li felloa kapele ho lisebelisoa tse kang metsi, motlakase, lipalangoang, pampiri, tse emeng, tlhokomelo le lisebelisoa ho bolela tse maloa feela.Liphuputso li boetse li senotse tsebo e nyane ea tshebetso ea tikoloho le botsitso ke bankakarolo ba sekolo.Sena se bakiloe ke ho haelloa ke moralo oa leano ke likolo tse ileng tsa mpefatsoa ke khaello ea matlafatso ho tsoa boitseaning ba likolo tsa botala bakeng sa ntshetsopele e tsitsitseng / Environmental Sciences / D.Litt. Phil (Environmental education)
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Case study of comptencies of technology education e-tutors in construction of design process at an open and distance e-learning institution / Case study of competencies of technology education e-tutors in construction of design process at an open and distance e-learning institutionSedio, Mpipo Zipporah 29 March 2021 (has links)
Abstract in English, Sesotho and Zulu / The occurrence of Open Distance and e-Learning revolutionized Higher Education Institutions for students to access instruction at anytime and anywhere. Students benefitted instruction of anytime and anywhere in one of the Technology Education courses in ODeL from the e-tutors. As a result of the support from the e-tutors, the curriculum was designed to place a strong emphasis on the design process as the core around which the teaching of the curriculum should revolve. However, it is still not clear how effective is the content knowledge which relates to the design process from the e-tutors.
In acknowledgment from such a gap, this study aimed to determine the relationship between the e-tutors’ technological, pedagogical, content knowledge of teaching design process within Technology Education specialization. In order to achieve this purpose, two theories, namely Transactional distance and Connectivism were coined together with the Technological Pedagogical Content Knowledge (TPACK) framework to underpin the study. The philosophical worldview is pragmatism having employed mixed method. Participants in this study were 145 students who registered a year programme for two modules in the Bachelor of Education (B.Ed.) programme at a Higher Education institution were surveyed to collect the quantitative data. Data from the face-to-face semi-structured interviews were collected with five e-tutors from the research sites. Online observations data were collected from the e-tutor sites of the institution’s learning management system (LMS). The results suggest that e tutors still lack the technology knowledge in order to deliver the content aimed for the design process in an ODeL environment. Also, it was evidenced that the e-tutors have not acquired pedagogical strategies for driving the pedagogy for the design process in an ideal context of ODeL. It should also be borne in mind that findings for the content knowledge indicated that the e-tutors still lack the knowledge for exploiting content knowledge of the design process to suit an ODeL environment. These findings highlight a need for technology to support e tutors’ pedagogical strategies towards a meaningful understanding of the design process and its implications across ODeL contexts. / Ketsahalo ea Open Distance le e-Learning e ntlafalitse litsi tsa thuto e phahameng bakeng sa baithuti ho fihlella taeo nako efe kapa efe le kae kapa kae. Baithuti ba ile ba rua molemo taelong ea nako efe kapa efe le kae kapa kae ho e 'ngoe ea lithuto tsa Technology Technology ho ODeL ho tsoa ho li-tutors. Ka lebaka la ts'ehetso e tsoang ho li-tutors, kharikhulamo e ne e etselitsoe ho hatisa ka matla ts'ebetso ea moralo e le khubu eo thuto ea kharikhulamo e lokelang ho potoloha ho eona. Leha ho le joalo, ha ho sa hlaka hore na tsebo ea litaba e sebetsa hantle hakae e amanang le tšebetso ea moralo ho tsoa ho li-tutors.
Ho ananela lekhalo le joalo, phuputso ena e ne e ikemiselitse ho tseba kamano lipakeng tsa theknoloji ea "e-tutors", thuto ea thuto, tsebo ea litaba ea ts'ebetso ea moralo oa ho ruta ka har'a tsebo ea thuto ea Technology. Bakeng sa ho fihlela sepheo sena, ho ile ha qaptjoa likhopolo tse peli, e leng Transactional distance le Connectivism hammoho le sebopeho sa Technological Pedagogical Content Knowledge (TPACK) ho tšehetsa thuto. Pono ea lefatše ea filosofi ke pragmatism e sebelisang mokhoa o tsoakaneng. Barupeluoa thutong ena e ne e le baithuti ba 145 ba ngolisitseng lenaneo la selemo bakeng sa li-module tse peli lenaneong la Bachelor of Education (B.Ed.) setsing sa Thuto e Phahameng ba ile ba hlahlojoa ho bokella lintlha tse ngata. Lintlha tse tsoang lipuisanong tsa sebopeho sa sefahleho li ile tsa bokelloa le barupeli ba bahlano ba tsoang libakeng tsa lipatlisiso. Lintlha tsa tlhaiso-leseling ka inthanete li ile tsa bokelloa ho tsoa litsing tsa e-tutor tsa sistimi ea taolo ea ho ithuta ea setheo (LMS). Liphetho li fana ka maikutlo a hore barupeli ba ntse ba haelloa ke tsebo ea mahlale a morao-rao molemong oa ho fana ka litaba tse reretsoeng ts'ebetso ea boqapi tikolohong ea ODeL. Hape, ho ile ha pakoa hore li-e-tutors ha li e-so fumane maano a thuto ea ho khanna lithuto tsa thuto bakeng sa moetso oa moralo ka mokhoa o loketseng oa ODeL. Hape ho lokela ho hopoloa hore liphuputso tsa tsebo ea litaba li bontšitse hore li-e-tutors li ntse li haelloa ke tsebo ea ho sebelisa tsebo ea litaba tsa moralo oa moralo ho latela tikoloho ea ODeL. Liphuputso tsena li totobatsa tlhoko ea mahlale a morao-rao ho ts'ehetsa maano a thuto a barupeli ho fihlela kutloisiso e hlakileng ea ts'ebetso ea moralo le litlamorao tsa ona maemong a ODeL. / Ukutholakala kwe-Open Distance ne-e-Learning kuguqula izikhungo zemfundo ephakeme zabafundi ukuthi bathole imfundo nganoma yisiphi isikhathi noma kuphi. Abafundi bahlomule ngokufundiswa nganoma isiphi isikhathi noma kuphi kwesinye sezifundo zeTechnology Education ku-ODeL kubafundisi be-e. Njengomphumela wokwesekwa okwenziwa abafundisi be-e-tutors, ikharikhulamu yakhelwe ukugcizelela kakhulu inqubo yokwakhiwa njengongqikimba okumele kufundiswe ngayo ikharikhulamu. Kodwa-ke, akukacaci ukuthi lusebenza kangakanani ulwazi lokuqukethwe oluphathelene nenqubo yokwakha evela kubafundisi be-e.
Ngokwazisa ngaleligebe elinje, lolu cwaningo luhlose ukucacisa ubudlelwano phakathi kwezobuchwepheshe be-e-tutors, ubuchwepheshe bokufundisa, ulwazi lokuqukethwe lwenqubo yokwakhiwa kokufundisa ngaphakathi kobuchwepheshe be-Technology Education. Ukufeza le njongo, imibono emibili, okungukuthi iTransactional distance neConnectivism yahlanganiswa kanye nohlaka lweTechnological Pedagogical Content Knowledge (TPACK) ukusekela ucwaningo. Umbono wezwe wefilosofi yi-pragmatism esebenzisa indlela exubile. Ababambe iqhaza kulolu cwaningo bekungabafundi abayi-145 ababhalise uhlelo lonyaka lwamamojula amabili kuhlelo lweBachelor of Education (B.Ed.) esikhungweni seMfundo ePhakeme bahlolisiswa ukuqoqa imininingwane yobungako. Imininingwane evela ezingxoxweni ezihlelekile ezenziwe ubuso nobuso zaqoqwa nama-e-tutors amahlanu avela kumasayithi ocwaningo. Idatha yokubuka eku-inthanethi yaqoqwa kusuka kumasayithi e-e-tutor ohlelo lokuphatha lokufunda (LMS). Imiphumela iphakamisa ukuthi abafundisi be-e basenalo ulwazi lobuchwepheshe ukuze bakwazi ukuletha okuqukethwe okuhloselwe inqubo yokwakhiwa endaweni ye-ODeL. Futhi, kufakazelwe ukuthi abafundisi be-e abakawatholi amasu okufundisa okushayela inqubo yokuqamba ngendlela efanelekile ye-ODeL. Kumele futhi kukhunjulwe ukuthi okutholakele kolwazi lokuqukethwe kukhombisile ukuthi ama-e-tutors asenalo ulwazi lokusebenzisa ulwazi lokuqukethwe kwenqubo yokwakhiwa ukuze ivumelane nemvelo ye-ODeL. Lokhu okutholakele kugqamisa isidingo sobuchwepheshe ukuxhasa amasu e-tutors 'pedagogical maqondana nokuqonda okunenjongo kwenqubo yokwakhiwa nemithelela yayo kuzo zonke izingqikithi ze-ODeL. / Curriculum and Instructional Studies / Ph. D. (Science and Technology Education)
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Mapeamento metabólico cortical por espectroscopia funcional em sujeitos saudáveis submetidos a estimulação elétrica do nervo acessórioBandeira, Janete Shatkoski January 2017 (has links)
A estimulação elétrica periférica (PES), que abrange diversas técnicas com respostas fisiológicas diversas, tem apresentado em alguns casos resultados clínicos promissores para o tratamento da dor e reabilitação clínica. No entanto, as respostas encontradas são heterogêneas, principalmente porque há uma falta de compreensão em relação ao seu mecanismo de ação. Neste estudo, buscamos avaliar os efeitos da PES através da medição da ativação cortical cerebral utilizando a espectroscopia funcional por infravermelho (fNIRS). A fNIRS é um método de imagem óptica funcional que avalia mudanças hemodinâmicas nas concentrações de hemoglobina oxigenada (HbO) e desoxigenada (HbR), relacionadas à atividade cortical. Nós hipotetizamos que a PES do nervo acessório espinal (ASN) pode promover a ativação do córtex motor (MC) e do córtex pré-frontal dorsolateral (DLPFC), relacionados ao processamento da dor. Quinze voluntários saudáveis receberam estimulação elétrica ativa e sham em um ensaio clínico randomizado cruzado. A resposta hemodinâmica à estimulação elétrica unilateral direita do nervo acessório com 10 Hz foi medida pela espectroscopia funcional por um sistema de 40 canais. A variação de HbO nas áreas corticais de interesse mostrou ativação do DLPFC direito (p=0,025) e do MOTOR esquerdo (p=0,042) no grupo ativo comparado com sham. Em relação ao DLPFC esquerdo (p=0,610) e ao MOTOR direito (p=0,154), não houve diferença estatística entre os grupos. Como na modulação top-down, a estimulação bottom-up do nervo acessório parece ativar as mesmas áreas corticais, relacionadas às dimensões sensório-discriminativas e afetivo-motivacionais da dor. Esses resultados fornecem evidência adicional para desenvolver e otimizar o uso clínico da estimulação elétrica periférica. / Peripheral electrical stimulation (PES), which encompasses several techniques with heterogeneous physiological responses, has shown in some cases remarkable outcomes for pain treatment and clinical rehabilitation. However, results are still mixed, mainly because there is a lack of understanding regarding its neural mechanisms of action. In this study, we aimed to assess its effects by measuring cortical activation as indexed by functional near infrared spectroscopy (fNIRS). fNIRS is a functional optical imaging method to evaluate hemodynamic changes in oxygenated (HbO) and de-oxygenated (HbR) blood hemoglobin concentrations in cortical capillary networks that can be related to cortical activity. We hypothesized that PES of accessory spinal nerve (ASN) can promote cortical activation of motor cortex (MC) and dorsolateral prefrontal cortex (DLPFC) pain processing cortical areas. Fifteen healthy volunteers received both active and sham ASN electrical stimulation in a crossover design. The hemodynamic response to unilateral right ASN burst electrical stimulation with 10 Hz was measured by a 40- channel fNIRS system. The effect of ASN electrical stimulation over HbO concentration in cortical areas of interest was observed through the activation of right- DLPFC (p=0.025) and left-MOTOR (p=0.042) in the active group but not in sham group. Regarding left-DLPFC (p=0.610) and right-MOTOR (p=0.174) there was no statistical difference between groups. As in non-invasive brain stimulation (NIBS) topdown modulation, bottom-up electrical stimulation to the accessory spinal nerve seems to activate the same critical cortical areas on pain pathways related to sensorydiscriminative and affective-motivational pain dimensions. These results provide additional mechanistic evidence to develop and optimize the effects of peripheral neural electrical stimulation.
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