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Adipose stromal cells enhance keratinocyte survival and migration in vitro, and graft revascularization in mouse wound healing modelKnowles, Kellen Alexander 11 December 2013 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / In the US, more than 1 million burn injuries are reported annually. About 45,000 injuries due to fires and burns result in hospitalization and ten percent of these result in death every year. Advances in burn treatment have led to a reduction in mortality rate over the last decades. Since more patients are surviving the initial resuscitation phase even with very large areas of skin being burned away, wound care has become increasingly important to ensure continued patient survival and improvement. While currently a common treatment for third degree burn wounds, skin grafts have several drawbacks. The availability of donor sites for autografts may be limited, especially in incidences of extensive skin loss. The rejection associated with the use of allografts and xenografts may render them inadequate or undesirable. Even if a suitable graft is found, poor retention due to infection, hematoma, and low vascularity at the recipient site are other drawbacks associated with the use of skin grafts as a primary treatment for severe burn wounds. As such, research has been done into alternative treatments, which include but are not limited to artificial skin, cell therapy, and growth factor application. We propose the delivery of adipose derived stem cells (ASC) in combination with endothelial progenitor cells (EC) via Integra Dermal Regenerative Template (DRT) to promote faster graft vascularization and thus faster healing of wounds. Integra DRT is an acellular skin substitute that consists of a dermal layer composed of bovine collagen and chondroitin-6-sulfate glycosaminoglycan, and an "epidermal" layer, which consists of silicone polymer. This silicone layer is removed after the collagen matrix is adequately vascularized (usually takes 2-3 weeks), and then a thin layer autograft is applied to the top of the neo-dermis. ASC are derived from the stromal-vascular fraction (SVF) of adipose tissue and are a readily available, pluripotent, mesenchymal cell known to promote angiogenesis. They are being explored as a treatment for a myriad of diseases and conditions, including wound healing. In combination with ECs, they form stable microvessel networks in vitro and in vivo. In our work, we found that ASC+EC form stable microvessel networks when cultured on Integra DRT. Also, ASC and ASC+EC conditioned media promoted both survival and migration of human epidermal keratinocytes compared to control medium. In a full thickness wound healing model, using healthy NSG mice, the ASC+EC case showed a significantly higher rate of wound closure compared to control. Based on best linear unbiased estimates (BLUE), the difference between the healing rates of ASC alone treatment and the Control treatment group is -0.45 +/- 0.22 mm²/day (p=0.041), which is not less than 0.025 and thus not statistically significant (Bonferroni Adjusted). However, the BLUE for the difference between the ASC+EC group and the Control group healing rates is -0.55 +/- 0.28 mm²/day (p = 0.017<0.025, Bonferroni Adjusted), which is statistically significant. Histology revealed a significantly higher number of vessels compared to control in both ASC alone and ASC+EC case. CD31 staining revealed the presence of human vessels in ASC+EC treatment scaffolds. We conclude that the combination of ASC and EC can be used to accelerate healing of full-thickness wounds when delivered to site of the wound via Integra. This result is especially compelling due to the fact that the mice used were all healthy. Thus our treatment shows an improvement in healing rate even compared to normal wound healing.
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Advancing the Filling Process in Agricultural Machinery : Hopper observation technology for improved filling in Väderstad´s Seed Hawk 600-900C / Förbättring av fyllningsprocessen i jordbruksmaskiner : Övervakningssystem av sålådor för bättre påfyllning av Väderstads Seed Hawk 600-900CAbou Shkair, Ali, Augustini, Jakob January 2024 (has links)
This master’s thesis was conducted in the spring of 2024 at Väderstad AB, a companyknown for producing high-performance agricultural machines, such as seeding machines. Among these machines, the Seed Hawk 600-900C is an important machine for thecompany’s future. The innovation department at Väderstad has developed an automatic Bag Slicer, capable of slicing large bags of seeds/fertilizer without requiring the farmer to climb onto the machine, a cumbersome and hazardous task. Several challenges arisein integrating the Bag Slicer onto their machines, which has hindered its implementation.These challenges have been thoroughly investigated, and one has been selected as thepriority for resolution: enabling the observation of the filling process without the need for climbing onto the hopper. To address this challenge, theoretical studies, concept development, and investigations in the 3D software Blender have been conducted. Creo Parametric was utilized to assemble the Bag Slicer onto the Seed Hawk machine and design other essential components. Coloring, animations, and renderings were created in Blender to create a configuration of cameras, lights, cables, and investigate their properties. This configuration provides users witha comprehensive overview of the filling process and enables operation of the Bag Slicerin the field from the safety of a tractor or wheel loader. Consideration has been given to the conditions occurring inside and around the Seed Hawk machine when specifyingall the different components and operational requirements. The entire configuration was compiled into a complete list of specifications, constituting the main result of this thesis.
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Exploring the practice of quality control in the onscreen marking of ordinary level Biology in ZimbabweMasiri, Ebba 02 1900 (has links)
The purpose of this study was to explore the practice of quality control in the onscreen marking (OSM) environment of Biology (5008) examinations between 2013 and 2017. Examination marking is gradually being migrating from paper-based marking (PBM) to OSM in a bid to improve the efficiency and quality of marking. The Zimbabwe School Examinations Council (ZIMSEC) introduced OSM for some O Level subjects in June 2012, in a context characterised by a persistent economic crisis, patchy internet coverage, erratic power supplies and low digital literacy, among other challenges. The Council encountered some difficulties related to quality control, which triggered this qualitative instrumental single case study that was informed by the ontology, epistemology, methods and axiology of the constructivist philosophy. Data were collected through face-to-face and focus group interviews on the WhatsApp platform with 4 subject managers, 11 senior markers and 18 normal markers, and through document review. The findings of the study suggest that the quality of marking was influenced by the context in which the examinations were marked. The socio-political climate that prevailed in Zimbabwe impacted on the technological infrastructure for the OSM and the digital literacy of the examination personnel. The capacity of the examiners to work in the OSM environment was influenced by knowledge and skills transfer from training and standardisation to the live marking. The quality of marking was monitored by the seeds approach to script moderation, automatically generated reports and audit trails, and escalation of problem scripts. It was also influenced by the structure of the question papers, cognitive demands of the questions and mark schemes on the examiners, spaces provided for candidates’ responses and mark scheme features such as language and marks to marking points ratio. The assessment framework provided by the syllabus guided the design and marking of Biology examinations. From these findings, a framework that could guide the practice of quality control in the OSM environment was formulated. OSM technology could enhance the quality of marking Biology examinations, thereby eliminating challenges associated with PBM. Some of the opportunities were, however, reduced by the challenges encountered during the OSM of the examinations. It is recommended that ZIMSEC put in place policies and procedures that could guide specific quality control activities in the OSM environment and establish computer centres in the provincial capital towns. The Council could also consider benchmarking examiner recruitment, training and standardisation procedures with international examination authorities. / Tsvakurudzo ino yanga yakananga kuvandudza nharaunda yemakwenyero ebvunzo kubudikidza nemichina pachidzidzo cheBhayaroji, 5008 pakati pemakore a2013-2017. Vandudzo iyi iri kuuya zvishoma nezvishoma kubva pakukwenya pamapepa zvichienda mukukwenya nemichina (on screen marking :OSM ) nechinangwa chekuda kukwenenzvera mhando yebasa rezvekukwenya . Bazi rebvunzo reZimbabwe School Examinations Council (ZIMSEC) rakavarura kukwenya kubudikidza nemichina (OSM) kubvunzo dzedanho reOdhinari revhuru muna Chikumi 2012 , mumamiriro anozivikanwa ematambudziko ezveupfumi, masaisai eindaneti asingavimbiki anouya zvigamba zvigamba , magetsi asingawanikwe nguva dzose, nezivo yezvemichina muvakwenyi isina kupararira pakati pezvimwe zvimhingamupini. Kanzuru yezvebvunzo yakasangana nemamwe matambudziko ane chokuita nounaku hwezvemakwenyerwe ebvunzo hwakakonzera kuti paitwe tsvakurudzo ino yezveudzamu (qualitative) muchinzvimbo chiduku chakasarudzwa (case study) yaitungamirirwa nemaziviro evacho vanoona nezvekukwenya bvunzo (interpretivist epistemology) nemaziviro okuti chokwadi chinosiyana nekusiyana kwenharaunda nokuti chigadzirwa chevarimukati mekukwenya (constructivist ontology), nekuumba mufungo kubudikidza neumboo huchabuda mutsvakurudzo (inductive theory) nenzira nezvinokosheswa nenharaunda mukuumba ruzivo (constructivist philosophy). Umboo hwetsvakurudzo hwakawanikwa kubudikidza nebvunzurudzo ine udzamu padungamunhu nemumapoka nekupindurana padare reWatsiApu nevanotungamira zvidzidzo (Subject managers ) vana , zvidza mune zvokukwenywa bvunzo gumi neumwe, nevamwewo vakwenyi gumi nevasere uye kuongorora magwaro. Mamiriro ezvemagariro nematongerwo enyika mu / Ihloso yaleli rhubhululo bekukuphenya indlela ikhwalithi elawulwa ngayo ngehlelo lokutshwaya ngekhomphyutha kwe enhlahlubo zeBhayiloji (5008) phakathi komnyaka ka-2013 no-2017. Ukutshwaywa kwe enhlahlubo kancanikancani kuyasuka ehlelweni lokutshwaya iphepha ngesandla (PBM) kuya ehlelweni lokutshwaya ngekhomphyutha (OSM) ngomzamo wokuthuthukisa umsebenzi omuhle kanye nokuletha iqophelo eliphezulu lokutshwaya. Hlangana nezinye iintjhijilo, UMkhandlu wezokuTshwaywa kwe eNhlahlubo eZimbabwe (Zimbabwe School Examinations Council) (ZIMSEC) sewungenise ihlelo le-OSM kwezinye iimfundo zesigaba sika-O Level ngenyangaka Mgwengweni 2012, ngaphasi kobujamo obumbibe zomnotho, kobujamo obumaratha be-inthanedi, obuqokeme kobokuphakelwa ngegezi kanye na ngaphasi kwezinga eliphasi lefundo ye dijithali. UMkhandlu uhlangabezene nobunye ubudisi obumalunga nanokulawulwa kwekhwalithi, okubujamo obukhwezelele isizathu sokobana kube nerhubhululo linye elisebenzako elisebenzisa indlela yerhubhululo yekulumo, kanti lokhu kwabangelwayi-ontholoji, i-ephistemoloji, iindlela zerthubhululo kanye ne-akziyoloji yefilosofi i-constructivist philosophy. Idatha ibuthelelwe ngendlela yehlolombono yokubuza umuntu ngamunye ubuso nobuso kanye nokubuza iinqhema zabantu ezinqotjhiwe kokukundla yezokucocisana, i-WhatsApp platform kanye nabaphathi beemfundo aba-4 subject managers, abatshwayi abakhulu abali-11, kanye nabatshwayi abajayelekileko abali-18, kanti lokhu kwenziwa ngokubuyekeza umtlolo. Ilwazi elifumane keerhubhululweni liphakamisa kobana izinga lekhwalithi lokutshwaya laba nomthintela wobujamo/wendawo lapho iinhlahlubo zatshwaywa khona. Ubujamo bezehlalakuhle yabantu kezepolotik iebebusezweni leZimbabwe laba nomthelela phezu komthanga lasisekelo wethekinoloji, kanti kwathinta abasebenzi behlelo le-OSM kanye nezinga lefundo yedijithali. Amandla wekghono labatshwayi lokusebenza ebhodulukweni le-OSM lalilawulwa kudluliselwa kwelwazi kanye namakghonofundwa ukusukela ekubandulweni kanye nokwenza izinto ngendlela efanako ehlelweni elibonakala ngamehlo lokutshwaya. Izinga lokutshwaya lalitjhejwe yindlela yokulinganiswa kwamaphepha atshwayiwako, ihlelo le-seeds approach to script moderation, kanti ihlelwe lingokwalo lihlanganisa imibiko begodu lilandelela ukuhlolwa, kanti goduli yakwazi nokuveza amaphepha ane miraro. Leli hlelo begodula lilawulwa sisakhiwo sephepha lemibuzo, lilwazi elifunekako ephepheni lemibuzo kanye namaskimu wamaksi phezu kwabatshwayi bamaphepha, iinkhala ezenzelwako bana abafundi baphendulele kizo kanye namaskimu wokutshwaya okunje ngelimi kanye namamaksi asesilinganiswe nisamamaksi, phecelezi-marking points ratio. Isakhiwo sokuhlola sinikelwa yisilabhasi, okungiyo eyikombandlela yedizayini kanye nokutshwaywa kwe enhlahlubo zeBhayiloji. Ngalelilwazi elitholakeleko, kukghonakele ukuthi kutlanywe isakhiwo ebesingabayi kombandlela yendlela engalandelwa ukulawula ikhwalithi ebhodulukweni ye-OSM. Ithekinoloji ye-OSM beyinga siza izinga lokumakha iinhlahlubo zeBhayiloji, ngalokho lokhu bekungaphungula iintjhijilo ezihlobene nehlelo le-PBM. Nanyana kunjalo, amanye amathuba, aphungulwazi intjhijilo ekuhlangabezenwe nazo nakutshwaywa iinhlahlubo zehlelo le-OSM. Kuye kwa tjhukunyiswa ukobana i-ZIMSEC izene mithethomgomo kanye ne enkambiso ezingabayikombandlela elayela imisebenzi ethile koyokulawulwa kwekhwalithi ebhodulukweni le-OSM kanye nokuhloma iinkhungo zekhomphyutha kumadorobhahloko we emfunda. UMkhandlu begodu ungatjheja yokubeka izinga lokuqatjhwa kwabatshwayi, lokubandulwa kanye nehlelolokwenza izinto ngendlela efanako neyamaziko we entjhabatjhaba alawula iinhlahlubo. / Science and Technology Education / D. Phil. (Education)
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Exploring the practice of quality control in the onscreen marking of ordinary level Biology in ZimbabweMasiri, Ebba 06 October 2020
Text in English, abstract in English, Shona and Xhosa / The purpose of this study was to explore the practice of quality control in the onscreen marking (OSM) environment of Biology (5008) examinations between 2013 and 2017. Examination marking is gradually being migrating from paper-based marking (PBM) to OSM in a bid to improve the efficiency and quality of marking. The Zimbabwe School Examinations Council (ZIMSEC) introduced OSM for some O Level subjects in June 2012, in a context characterised by a persistent economic crisis, patchy internet coverage, erratic power supplies and low digital literacy, among other challenges. The Council encountered some difficulties related to quality control, which triggered this qualitative instrumental single case study that was informed by the ontology, epistemology, methods and axiology of the constructivist philosophy. Data were collected through face-to-face and focus group interviews on the WhatsApp platform with 4 subject managers, 11 senior markers and 18 normal markers, and through document review. The findings of the study suggest that the quality of marking was influenced by the context in which the examinations were marked. The socio-political climate that prevailed in Zimbabwe impacted on the technological infrastructure for the OSM and the digital literacy of the examination personnel. The capacity of the examiners to work in the OSM environment was influenced by knowledge and skills transfer from training and standardisation to the live marking. The quality of marking was monitored by the seeds approach to script moderation, automatically generated reports and audit trails, and escalation of problem scripts. It was also influenced by the structure of the question papers, cognitive demands of the questions and mark schemes on the examiners, spaces provided for candidates’ responses and mark scheme features such as language and marks to marking points ratio. The assessment framework provided by the syllabus guided the design and marking of Biology examinations. From these findings, a framework that could guide the practice of quality control in the OSM environment was formulated. OSM technology could enhance the quality of marking Biology examinations, thereby eliminating challenges associated with PBM. Some of the opportunities were, however, reduced by the challenges encountered during the OSM of the examinations. It is recommended that ZIMSEC put in place policies and procedures that could guide specific quality control activities in the OSM environment and establish computer centres in the provincial capital towns. The Council could also consider benchmarking examiner recruitment, training and standardisation procedures with international examination authorities. / Tsvakurudzo ino yanga yakananga kuvandudza nharaunda yemakwenyero ebvunzo kubudikidza nemichina pachidzidzo cheBhayaroji, 5008 pakati pemakore a2013-2017. Vandudzo iyi iri kuuya zvishoma nezvishoma kubva pakukwenya pamapepa zvichienda mukukwenya nemichina (on screen marking :OSM ) nechinangwa chekuda kukwenenzvera mhando yebasa rezvekukwenya . Bazi rebvunzo reZimbabwe School Examinations Council (ZIMSEC) rakavarura kukwenya kubudikidza nemichina (OSM) kubvunzo dzedanho reOdhinari revhuru muna Chikumi 2012 , mumamiriro anozivikanwa ematambudziko ezveupfumi, masaisai eindaneti asingavimbiki anouya zvigamba zvigamba , magetsi asingawanikwe nguva dzose, nezivo yezvemichina muvakwenyi isina kupararira pakati pezvimwe zvimhingamupini.
Kanzuru yezvebvunzo yakasangana nemamwe matambudziko ane chokuita nounaku hwezvemakwenyerwe ebvunzo hwakakonzera kuti paitwe tsvakurudzo ino yezveudzamu (qualitative) muchinzvimbo chiduku chakasarudzwa (case study) yaitungamirirwa nemaziviro evacho vanoona nezvekukwenya bvunzo (interpretivist epistemology) nemaziviro okuti chokwadi chinosiyana nekusiyana kwenharaunda nokuti chigadzirwa chevarimukati mekukwenya (constructivist ontology), nekuumba mufungo kubudikidza neumboo huchabuda mutsvakurudzo (inductive theory) nenzira nezvinokosheswa nenharaunda mukuumba ruzivo (constructivist philosophy).
Umboo hwetsvakurudzo hwakawanikwa kubudikidza nebvunzurudzo ine udzamu padungamunhu nemumapoka nekupindurana padare reWatsiApu nevanotungamira zvidzidzo (Subject managers ) vana , zvidza mune zvokukwenywa bvunzo gumi neumwe, nevamwewo vakwenyi gumi nevasere uye kuongorora magwaro.
Mamiriro ezvemagariro nematongerwo enyika mu / Ihloso yaleli rhubhululo bekukuphenya indlela ikhwalithi elawulwa ngayo ngehlelo lokutshwaya ngekhomphyutha kwe enhlahlubo zeBhayiloji (5008) phakathi komnyaka ka-2013 no-2017. Ukutshwaywa kwe enhlahlubo kancanikancani kuyasuka ehlelweni lokutshwaya iphepha ngesandla (PBM) kuya ehlelweni lokutshwaya ngekhomphyutha (OSM) ngomzamo wokuthuthukisa umsebenzi omuhle kanye nokuletha iqophelo eliphezulu lokutshwaya. Hlangana nezinye iintjhijilo, UMkhandlu wezokuTshwaywa kwe eNhlahlubo eZimbabwe (Zimbabwe School Examinations Council) (ZIMSEC) sewungenise ihlelo le-OSM kwezinye iimfundo zesigaba sika-O Level ngenyangaka Mgwengweni 2012, ngaphasi kobujamo obumbibe zomnotho, kobujamo obumaratha be-inthanedi, obuqokeme kobokuphakelwa ngegezi kanye na ngaphasi kwezinga eliphasi lefundo ye dijithali. UMkhandlu uhlangabezene nobunye ubudisi obumalunga nanokulawulwa kwekhwalithi, okubujamo obukhwezelele isizathu sokobana kube nerhubhululo linye elisebenzako elisebenzisa indlela yerhubhululo yekulumo, kanti lokhu kwabangelwayi-ontholoji, i-ephistemoloji, iindlela zerthubhululo kanye ne-akziyoloji yefilosofi i-constructivist philosophy. Idatha ibuthelelwe ngendlela yehlolombono yokubuza umuntu ngamunye ubuso nobuso kanye nokubuza iinqhema zabantu ezinqotjhiwe kokukundla yezokucocisana, i-WhatsApp platform kanye nabaphathi beemfundo aba-4 subject managers, abatshwayi abakhulu abali-11, kanye nabatshwayi abajayelekileko abali-18, kanti lokhu kwenziwa ngokubuyekeza umtlolo. Ilwazi elifumane keerhubhululweni liphakamisa kobana izinga lekhwalithi lokutshwaya laba nomthintela wobujamo/wendawo lapho iinhlahlubo zatshwaywa khona. Ubujamo bezehlalakuhle yabantu kezepolotik iebebusezweni leZimbabwe laba nomthelela phezu komthanga lasisekelo wethekinoloji, kanti kwathinta abasebenzi behlelo le-OSM kanye nezinga lefundo yedijithali. Amandla wekghono labatshwayi lokusebenza ebhodulukweni le-OSM lalilawulwa kudluliselwa kwelwazi kanye namakghonofundwa ukusukela ekubandulweni kanye nokwenza izinto ngendlela efanako ehlelweni elibonakala ngamehlo lokutshwaya. Izinga lokutshwaya lalitjhejwe yindlela yokulinganiswa kwamaphepha atshwayiwako, ihlelo le-seeds approach to script moderation, kanti ihlelwe lingokwalo lihlanganisa imibiko begodu lilandelela ukuhlolwa, kanti goduli yakwazi nokuveza amaphepha ane miraro. Leli hlelo begodula lilawulwa sisakhiwo sephepha lemibuzo, lilwazi elifunekako ephepheni lemibuzo kanye namaskimu wamaksi phezu kwabatshwayi bamaphepha, iinkhala ezenzelwako bana abafundi baphendulele kizo kanye namaskimu wokutshwaya okunje ngelimi kanye namamaksi asesilinganiswe nisamamaksi, phecelezi-marking points ratio. Isakhiwo sokuhlola sinikelwa yisilabhasi, okungiyo eyikombandlela yedizayini kanye nokutshwaywa kwe enhlahlubo zeBhayiloji. Ngalelilwazi elitholakeleko, kukghonakele ukuthi kutlanywe isakhiwo ebesingabayi kombandlela yendlela engalandelwa ukulawula ikhwalithi ebhodulukweni ye-OSM. Ithekinoloji ye-OSM beyinga siza izinga lokumakha iinhlahlubo zeBhayiloji, ngalokho lokhu bekungaphungula iintjhijilo ezihlobene nehlelo le-PBM. Nanyana kunjalo, amanye amathuba, aphungulwazi intjhijilo ekuhlangabezenwe nazo nakutshwaywa iinhlahlubo zehlelo le-OSM. Kuye kwa tjhukunyiswa ukobana i-ZIMSEC izene mithethomgomo kanye ne enkambiso ezingabayikombandlela elayela imisebenzi ethile koyokulawulwa kwekhwalithi ebhodulukweni le-OSM kanye nokuhloma iinkhungo zekhomphyutha kumadorobhahloko we emfunda. UMkhandlu begodu ungatjheja yokubeka izinga lokuqatjhwa kwabatshwayi, lokubandulwa kanye nehlelolokwenza izinto ngendlela efanako neyamaziko we entjhabatjhaba alawula iinhlahlubo. / Science and Technology Education / D. Phil. (Education)
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