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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Etude des effets de la stimulation électrique transcrânienne en courant continu (tDCS) sur la fonction motrice volontaire et semi-automatique chez des patients hémiparétiques post AVC / Impact of transcranial direct curent stimulation on voluntary and semi-automatic movement in patient with stroke

Geiger, Maxime 12 March 2019 (has links)
Chez les patients hémiparétiques chroniques, la tDCS a été testée sur diverses tâches du membre inférieur, montrant des résultats intéressants, mais parfois contradictoires. Cependant, les effets de la tDCS sur la fonction motrice volontaire (extension de genou) et semi-automatique (locomotion) chez des patients hémiparétiques ne sont pas encore totalement connus. L’objet de ce travail était d’évaluer contre placébo les effets de la tDCS en polarité anodale sur les fonctions motrices volontaires et semi-automatiques, chez des patients hémiparétiques. L’étude comporte deux parties : la première a pour but d’évaluer l’effet contre placébo de la tDCS bilatérale sur la force volontaire maximale du quadriceps parétique par isocinétisme, la seconde a pour objectif d’étudier les effets contre placébo des effets de la tDCS unilatérale sur la marche par analyse tridimensionnelle du mouvement. Les résultats ont montré une absence d’effet de la tDCS sur les deux types de mouvements étudiés. De plus, la tDCS n’a pas eu d’effet sur la spasticité du quadriceps ni sur la performance aux tests fonctionnels des patients hémiparétiques. Cela suggère qu’il n’y a pas d’intérêt à l’utilisation de la tDCS bilatérale pour améliorer une performance motrice maximale (l’extension de genou) ni de la tDCS unilatérale pour améliorer un mouvement semi-automatique (la locomotion) chez les patients hémiparétiques chroniques. Les perspectives envisagées sont de reconduire ces expérimentations chez un groupe homogène de patients hémiparétiques en phase aigüe ou subaigüe afin de potentialiser les phénomènes plastiques post-lésionnels. Ceci permettra de renforcer ou non l’intérêt de l’utilisation de la tDCS chez les patients hémiparétiques afin d’améliorer leurs performances motrices. / In chronic hemiparetic patients, the use of tDCS has been tested on various lower limb tasks, showing interesting but sometimes contradictory results. However, the effects of tDCS on voluntary (knee extension) and semi-automatic (locomotion) motor function in hemiparetic patients are not yet fully known. The purpose of this work was to quantify the effects of tDCS in anodal polarity on the voluntary and semi-automatic motor functions in placebo-controlled studies. The study is divided into two parts: the first aims to evaluate the effect against placebo of bilateral tDCS on the maximal voluntary force of the paretic quadriceps by isokinetic assessment, the second aims to study the effects against placebo of unilateral tDCS on the gait of chronic hemiparetic patients, assessed by three-dimensional gait analysis. The results showed an absence of effect of tDCS on the two types of movements studied. In addition, tDCS had no effect on quadriceps spasticity or functional test performance in hemiparetic patients. This suggests that there is no interest in using bilateral tDCS to improve maximal motor performance (knee extension) or unilateral tDCS to improve semi-automatic movement (locomotion) in chronic hemiparetic patients. The envisaged perspectives are to continue these experiments in a homogeneous group of hemiparetic patients in acute or subacute stroke patients in order to potentiate the post-lesional plastic phenomena. This will strengthen or not the interest of the use of tDCS in hemiparetic patients to improve their motor performance.
82

Komplexní diagnostika zděné konstrukce mostu / The Complex Diagnostics of Bricked Bridge Construction

Durčáková, Lenka January 2012 (has links)
Diploma thesis The complex diagnostics of bricked bridge construction is in the theoretical part focused on the summary of regulations of road and railway bridges. In the practical part was conducted the inspection and diagnostic survey of the railway viaduct on Křenová, near the main train station Brno.
83

En tvärsnittsstudie om sambandet mellan arbetskontrollokus och gränssättning mellan arbetsliv och privatliv

Hessel, Hedda, Sjölander, Fredrik January 2023 (has links)
The interest in boundaries between work and personal life has become more invigorated since the Covid-19 pandemic, where many people had to work from home which potentially blurred the lines between work and family life. This technological development which made working from home during the pandemic possible is not likely to stagnate. Therefore it is of importance to investigate boundaries and what other factors can possibly affect them further. One such factor being control and the belief that one does or does not have it. The aim of this study was to look for a relationship between Boundary Strength at Home (BSH) and Work Locus of Control (WLOC) with demographic variables such as age and gender. This was researched through a survey sent to different work related forums using a mix of snowball and convenience sample (n=153). The results did not support there being a relationship between BSH and WLOC. Although, the results did show an interaction effect between WLOC and age in relation to BSH. It is unclear why this interaction effect manifested but it suggests that age is not as trivial of a factor as first thought. Therefore we encourage further research into the relationship between age, WLOC and boundary management.
84

The Relationship of Training Frequency and Wilks Score in Competitive Swedish Classic Powerlifters : A Quantitative Questionnaire Study

Hillerström, Erik, Brandin, Whilliam January 2023 (has links)
Background: In strength sports, athletes must take several training variables into consideration whencreating a training program. One of the ground pillars is training frequency, but there is a lackof research done on competitive powerlifters. Therefore, the purpose of this study was toinvestigate the corelation between training frequency and performance, measured as Wilksscore, in competition for powerlifters. Methods: An online questionnaire was sent out through various social media platforms to activepowerlifters, with the purpose of gathering sufficient information on their training habits andcompetition scores. A total of 80 subjects followed through with the survey, but only 48 metthe final inclusion criteria. Participants were divided into three groups based on their trainingfrequency; separate groups were created for the different lifts. Total frequency was dived intothe groups (3, 4, >4) sessions per week, squat frequency into (1,2, >2), bench press (2,3,>3),deadlift (1,2,>2). Results: As the p-value of all the tests are larger than the alpha value (0,0125) there is no apparentdifference between the groups that can be attributed to the training frequency. Duringsubgroup analysis, there were no other significant correlations between Wilks score andcompetitive age, training frequency or training intensity. However, there was a trend for ancorrelation between training volume a slight effect on the total Wilks score (P = 0,077). Conclusion: Training frequency may not be an important factor for powerlifters after 1-2 sessions and aftera certain threshold of volume has been reached. However, a higher training frequency mayallow for higher training volumes which previous research has found favourable. Moreresearch over a longer time span is still needed.
85

Betonghållfasthet vs. normhållfasthet för cement : Underlag för framtida hantering av variationer i cementens normhållfasthet / Concrete Strength Vs. Strength of Cement : Support for future handling of variations in the cement standard strength

Tynhage, Ellinor, Lif, Emil January 2021 (has links)
Betong är ett material som används dagligen och finns i allt från skyskrapor och tunnlar till skulpturer och möbler. Tryckhållfastheten är en av betongens viktigaste egenskaper och med en konstant utvecklande bransch där det byggs mer och mer är det avgörande att betongen som används håller. Normhållfastheten hos cement kontrolleras regelbundet och visar i vissa fall variationer utanför cementens normala spann. Cementillverkare upptäcker dessa avsteg genom att granska varje leverans som produceras samt genom egna produktkontroller på fabriken. Vid upptäckta felmarginaler finns krav på att berörda kunder i branschen måste informeras för att exempelvis få en möjlighet till att kunna korrigera recept inför betongblandningen. Vid en lägre normhållfasthet i cement skapas generellt en lägre hållfasthet i betong och för att justera avvikelsen ökar betongtillverkare mängden cement i recepten för att kunna leverera en produkt med utlovad hållfasthet till kund. Slutresultatet kommer att hjälpa betongtillverkare att förutse hur betongen kan påverkas av en variation i cementens hållfasthet och vara ett hjälpmedel för hur receptet ska hanteras för att täcka upp eventuella variationer så att kunderna inte påverkas i lika stor grad. Arbetet innefattar tre betongrecept med separata vct som testas med cementen Anläggningscement Slite i en grov-, mellan- och finmald version. Gjutningen sker i Cementa Research laboratorium i Liljeholmen och sammanlagt utförs 18 gjutningar med 22 liter betong per gjutning. Totalt gjuts 216 kuber som sedan trycktestas vid 7 respektive 28 dygn i samma lokal. Data har sedan sammanställts för att kunna jämföras mot cementens normhållfasthet som har testats i Cementas lab i Slite. Arbetet har utförts åt Cementa AB och Thomas Concrete Group AB för att kontrollera sambandet mellan normhållfastheten i cement och den färdiga betongens hållfasthet. Sambandet är av stor vikt i den dagliga produktionen och är något som efterfrågats under lång tid. Resultatet från gjutningarna visar att det finns ett samband till en viss grad men på grund av komplikationer under gjutningarna har vissa värden inte blivit som förväntat. / Concrete is one of the world's most important building materials and is used in everything from skyscrapers, tunnels to sculptures and furniture. The strength of concrete is important and with a constantly developing industry where more and more is being built, it is vital that the concrete that is used holds. The work is performed on behalf of Cementa AB and Thomas Concrete Group AB to investigate the relation between the strength of cement and the strength of the concrete. The relation is of great importance in daily production and is something that has been requested for a long time. The standard strength of cement is checked regularly and shows in some cases deviations outside the normal range of the cement. Cementa detects these deviations by controlling shipped cement and by the product controls at the factory. If margins of error are discovered, there are requirements for those involved in the industry that they must inform the customers in order for them to correct their concrete mixes accordingly. At a lower standard strength in cement, a lower strength in concrete is generally created and to correct the deviation, the affected amount of cement in the recipe increases in order to be able to deliver a promised product to the customer. The end result will help concrete manufacturers predict how the concrete can be affected by a deviation of the strength of the cement and be a tool for how the recipe should be handled to cover any deviations so that customers are not affected to the same extent. The work includes three concrete recipes with separate w/c-ratios that were tested with the cement CEM I 42,5 N SR3 MH/LA in a coarse, medium and finely milled version. The casting took place in Cementa Research's laboratory in Liljeholmen and in summary, 18 castings were performed with 22 liters of concrete per casting. A total of 216 cubes were cast and then pressure tested at 7 and 28 days. The data has then been compiled to be able to be compared with the cement's standard strength that has been tested in Cementa's lab in Slite.
86

Creatine supplementation and resistance training in older adults

Brose, Andrea January 2001 (has links)
<p>[missing page:45]</p> / <p>BACKGROUND: Creatine monohydrate (CrM) supplementation during resistance exercise results in a greater increase in fat free mass (FFM), total body mass (TBM), and strength in young men and women. The purpose of the present investigation was to examine the interactive effects of creatine supplementation and resistance training on body composition, strength, and intramuscular total creatine concentration in older men and women.</p> <p>METHODS: Twenty-eight older men and women were randomly allocated, in a double blind fashion, to receive either CrM (n=14; CrM: 5g + 2g dextrose) or placebo (n=14; PL: 7g dextrose). Subjects participated in a 14 wk progressive, whole-body resistance training program. Pre-and post-training measurements included: 1 RM strength, isometric strength, body composition (TBM, FFM, %BF), muscle fiber area, and muscle total creatine and phosphocreatine.</p> <p>RESULTS: Training resulted in an increase in 1 RM strength for each of the 4 exercises (range = 26 - 60%) (p < 0.001), an increase in knee and dorsiflexion isometric strength (p < 0.001) and an improvement of performance on functional tasks (p < 0.001). Knee isometric strength was increased more for CrM (46.2%) as compared to PL (22.5%) (p < 0.05). Total body mass and lean body mass increased more for CrM (TBM: +1.2 kg; LBM: +1.7 kg) as compared to PL (TBM: -0.2 kg; LBM: 0.4 kg) (p < 0.05)</p> <p>CONCLUSIONS: We conclude that erM supplementation results in a greater increase in isometric knee extensor strength, total body mass and lean body mass during resistance training in older adults.</p> / Master of Science (MSc)
87

Utveckling och genomförbarhet av ett progredierat arbetsprov med uppresningar från stol som modalitet / Development and feasability of a chair-stand test

Aspholm, Rasmus January 2022 (has links)
Introduktion: Konditionstest utförs för att undersöka en persons aeroba eller anaeroba kapacitet. Många test använder sig av en wattbaserad styrning av effektutvecklingen. Det finns välutvecklade metoder för detta på cykel, men inte i form av uppresningar från stol. Studiens syfte var att utveckla och undersöka genomförbarheten av ett watt-styrt progredierat arbetsprov, med modaliteten uppresningar från stol, för att estimera anaerob kapacitet.   Metod: Det konstruerade arbetsprovet utgick från Borgs Cycle Strength test där deltagarna utförde stegrande intervaller till en intensitet där subjektiv ansträngningsnivå når ”mycket ansträngande”. Effektutvecklingen styrdes genom att kontrollera frekvensen av uppresningar med hjälp av metronom. 10 träningsvana deltagare rekryterades. Deltagarnas utförande spelades in på film, vilket möjliggjorde kontrollering av antal uppresningar för att estimera deltagarnas faktiska effekt mot fastställd effekt. Genom att jämföra knäledsvinkeln vid olika intensitetsnivåer undersöktes deltagarnas rörelseomfång av uppresningarna. Undersökning av deltagarnas subjektiva upplevelse av arbetsprovet gjordes genom att deltagarna besvarade 3 enkätfrågor efter utfört arbetsprov.    Resultat: Resultaten visar på att 7 av 9 deltagare utförde uppresningar med sådan frekvens att estimerad faktisk effekt kom nära fastställd effekt under intervallerna hela vägen upp till 17 på RPE-skalan. Vid skattning 17 på RPE-skalan avvek den estimerade faktiska effekten från den fastställda effekten med -31 watt. Alla deltagare förutom en befann sig inom det 95 procentiga konfidensintervallet. Resultatet visade att det gick bra att genomföra korrekta uppresningar vid låg och medelhög intensitet, däremot var det vid den sista intensitetsnivån en signifikant ökning av vinkeln i knäleden jämfört med den första intensitetsnivån (p= 0,035). Deltagarna upplevde att takten till uppresningarna gick att följa med hjälp av metronom.    Konklusion: Metronom kan användas för att styra frekvensen av uppresningar. Effekten går att stegra genom att endast öka antalet uppresningar, men vid hög intensitet klarade inte alla deltagare av att upprätthålla uppresningsfrekvensen eller att utföra korrekta uppresningar.
88

Kondiční příprava elitních lyžařů sjezdařů v České republice a v alpských zemích / Conditinal preparation of elite alpine skiers in Czech republic and alp leading countries

Gecelovský, Igor January 2015 (has links)
Defining the problem: The aim of this study was to compare the two training systems between the Czech system and the system of the alpine leading countries, fitness training downhill skiers in the adult category. The study group was composed of the top skiers in the category of adult women aged 20-25 years. The result was a difference in the quantity of training units (Czech 287 h - 328 h ALC). Alpine leading countrie's system were leading in the number of hours the load by 12.5% higher than the Czech system, which will be reflected in the overall results of athletes. It was a different number of hours of development of endurance and strength assumptions in the preparation period, which could have repercussions on the overall results, power plants in season 2012/2013. Method: My task will be to compare the method of retrieval and quantification of the preparatory period downhill skiers from the Czech Republic and downhill skiers from the Alpine leading countries. Materials to compare the final work will be available from coaches of both systems of the European team and the World Cup team and the Czech section of the Alpine Skiing (UAD). Goals: The aim of this work is the processing of data on the practice of downhill skiers in the women's category. Quantitative and qualitative comparison of the...
89

Aprimoramento do poliuretano a base de óleo de mamona na manufatura de Madeira Laminada Colada (MLC) de Cupressus lusitanica, Corymbia maculata e Hevea brasiliensis / Enhancement of castor oil-based polyurethane for manufacture of glued laminated timber (glulam) of Cupressus lusitanica, Corymbia maculata and Hevea brasiliensis

Cerchiari, Aline Maria Faria 05 June 2013 (has links)
O objetivo do presente trabalho foi encontrar novas espécies para o segmento de Madeira Laminada Colada e substituir adesivos tradicionais que emitem compostos voláteis tidos na literatura como não amigáveis ao meio ambiente. Foram caracterizadas as espécies Hevea brasiliensis (Seringueira), C. maculata (Maculata) e C. lusitanica (Cupressus) e sintetizado um poliuretano à base de óleo de mamona, sem solventes e aditivos, que foi utilizado na fabricação de corpos de prova para ensaios de cisalhamento. A resistência ao cisalhamento paralela às fibras foi a variável trabalhada para caracterizar as espécies e validar o poliuretano. O processo de produção desse poliuretano iniciou-se com as sementes de mamona produzidas, seguiu na extração à frio do óleo que foi comparado com um óleo comercial e culminou na síntese do poliuretano. O óleo comercial possibilitou a obtenção do melhor poliuretano devido a sua pureza. Não foram encontradas diferenças na aplicação do poliuretano quando aplicados em uma ou nas duas faces de contato a serem unidas nos corpos de prova das três espécies, vantagem do poliuretano que representa redução de custo na MLC. O poliuretano de mamona produzido em laboratório com óleo comercial superou o adesivo resorcinolformaldeído no que se refere à resistência ao cisalhamento da madeira de Cupressus e foi similar quando comparado à Seringueira. Seringueira e Cupressus mostraram-se aptas para a produção de madeira laminada colada, superando o Maculata em termos de qualidade mecânica. / The aim of this study was to indentify new species for the segment of glued laminated timber (glulam) and replace traditional adhesives that emit volatile compounds, reported in literature taken as unfriendly to the environment. We characterized species Hevea brasiliensis (Rubberwood), C. maculata (Maculata) and C. lusitanica (Cupressus). We synthesized castor oil-based polyurethane without additives and solvents, used in shear strength tests. The shear strength parallel to grain was the worked variable to characterize and validate the polyurethane species. The manufacturing process of polyurethane started with the production of castor oil seeds, followed by cold extraction of oil, which was compared with commercial oil, and the process culminated with the polyurethane synthesis. The commercial oil provided better polyurethane due to its purity. There were no differences in the polyurethane application in one or two of the contact faces to be joined in the manufacture process for wood test specimens of the three species, one advantage of polyurethane is cost reduction of the glulam. The castor oil-based polyurethane produced in the laboratory outperformed the commercial resorcinol-formaldehyde adhesive in terms of wood shear strength tests for Cupressus and was similar when in Rubberwood. Rubberwood and Cupressus proved suitable for the production of glulam, surpassing Maculata in terms of mechanical quality.
90

Avaliação da composição e da adesividade de obturações dos canais radiculares / Evaluation of composition and bond strength of root canal fillings

Plotegher, Fernanda 10 April 2014 (has links)
O objetivo do presente estudo in vitro foi avaliar a área ocupada pela guta-percha e cimento, bem como a resistência de união em canais radiculares obturados por diferentes técnicas: Schilder Modificada, Cone único, Thermafil e Híbrida de Tagger. Quarenta incisivos centrais superiores foram preparados com instrumentos rotatórios de NiTi até o diâmetro cirúrgico #70.02, e divididos em quatro grupos de acordo com a técnica utilizada para obturação dos canais (n=10): GI - Schilder Modificada, GII - Cone Único, GIII - Thermafil e GIV - Híbrida de Tagger. Os canais foram obturados com o cimento AH Plus misturado ao corante Rodamina. Feitas as obturações, realizou-se a remoção coronária e as raízes foram seccionadas no sentido horizontal, obtendo-se 3 fatias (2mm de espessura): cervical, médio e apical. Após o preparo, as fatias foram submetidas à mensuração da área total do canal radicular e da área de guta-percha, por meio de objetiva Plan S 1.0 X acoplada à câmera digital e do software Axiovision 4.8. A área do cimento obturador foi determinada pela fórmula Área do cana = Área guta-percha + Área cimento + Área espaços vazios. A resistência de união foi avaliada pelo teste de push-out e as falhas foram observadas em microscópio digital. Os dados foram analisados por Análise de Variância a dois critérios e teste Tukey HSD (p<0,05). Verificou-se diferença estatisticamente significante para técnica obturadora (p<0,05). Não houve diferença estatisticamente significante nos terços e para interação dos fatores (p>0,05). Os canais obturados pelas técnicas Thermafil e Schilder Modificada proporcionaram maiores áreas de guta-percha, diferindo estatisticamente dos obturados pelas técnicas de Cone único e Hibrida de Tagger (p<0,05). Na análise da área preenchida pelo cimento, verificou-se que nos espécimes obturados pelas técnicas Thermafil e Schilder Modificada houve menor área ocupada pelo cimento, diferindo dos obturados pelas técnicas Híbrida de Tagger e Cone Único (p<0,05). Na análise da resistência de união, houve diferença significante para técnica obturadora, terços e para a interação dos fatores (p<0,05). Os canais obturados pela técnica Híbrida de Tagger apresentaram maior valor de resistência de união, diferentes dos obturados pelas técnicas Cone Único, Schilder Modificada e Thermafil (p<0,05). Houve diferença estatisticamente significante entre os terços (p<0,05), sendo que o terço apical apresentou o maior valor de resistência de união. A análise da interação técnica versus terço demonstrou que os espécimes obturados pela técnica Híbrida de Tagger tiveram no terço apical a maior resistência de união, diferentes das demais técnicas e terços (p<0,05). Falhas adesivas foram mais frequentes em todos os grupos. Pode-se concluir que a maior área ocupada pela guta-percha e a menor área ocupada pelo cimento foram encontrados nos espécimes obturados com as técnicas Schilder Modificada e Thermafil. O maior valor de resistência de união foi encontrado nos canais obturados pela técnica Híbrida de Tagger, especialmente no terço apical. / Ther purpose of this in vitro study was to evaluate the area occupied by gutta-percha and sealer, as well the bond strength in root canals obturated with different techniques: Schilder&prime;s Modified, Single Cone, Thermafil and Tagger&prime;s Hybrid. Forty maxillary central incisors were prepared with NiTi rotary instruments to the diameter #70.02, and separated in four groups according to the technique used for root canal filling (n=10): GI - Schilder&prime;s Modified, GII - Single Cone, GIII Thermafil and GIV - Tagger&prime;s Hybrid. The roots canals were filled with sealer AH Plus mixed with Rhodamine dye. After obturation, coronary was removed and the root&prime;s were sectioned in the horizontal direction, obtaining 3 slices (2 mm thick): cervical, medium and apical. After preparation, the slices were subjected to measurement of the total roots canal area and gutta-percha&prime;s area, through objective Plan S 1.0 X coupled to the digital camera and Axiovision 4.8 software. The sealer&prime;s area was determined by the formula: roots canal&prime;s area = gutta-percha&prime;s area + sealer&prime;s area + void&prime;s area. Bond strength was evaluated by push-out test and the failures were observed in digital microscope. The results were analyzed by ANOVA two-way and Tukey HSD (p <0.05). It has been found a statistically significant difference for techniques (p <0.05). There was no statistically significant difference in thirds and interaction of the factors (p> 0.05). Root&prime;s canal filled by Thermafil and Schilder&prime;s Modified had higher gutta-percha&prime;s area than Single Cone and Tagger&prime;s Hybrid techniques (p <0.05). The analysis of the sealer&prime;s area, proved that the specimens filled by Thermafil and Schilder&prime;s Modified had smaller sealer&prime;s area, differing from Tagger&prime;s Hybrid and Single Cone (p <0.05) techniques. Bond strength&prime;s results demonstrated a significant difference for techniques, thirds and the interaction of this factors (p <0.05). Roots canals filled by Tagger&prime;s hybrid technique had higher bond strength than Single Cone, Schilder&prime;s Modified Thermafil techniques (p <0.05). There was a statistically significant difference between the thirds (p <0.05), and the apical third showed the highest bond strength&prime;s value. The analysis of interaction technique versus third, showed that the specimens filled by Taggers Hybrid in the apical third had the highest bond strength, different from the other techniques and thirds (p <0.05). Adhesive failures were more frequent in all groups. It was concluded that the highest area occupied of gutta-percha and the less sealer&prime;s area were found in roots canals filled with Schilder&prime;s Modified and Thermafil techniques. The highest bond strength was found in roots canals filled by Tagger&prime;s Hybrid technique, especially in the apical third.

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